WO2018012973A1

WO2018012973A1 - Toy water gun

Info

Publication number: WO2018012973A1
Application number: PCT/NL2017/050473
Authority: WO
Inventors: Peter Jan van der Molen; Johannes Wilhelmus VAN TUIL
Original assignee: White Water Holding B.V.
Priority date: 2016-07-14
Filing date: 2017-07-13
Publication date: 2018-01-18
Also published as: NL2017165B1

Abstract

A toy water gun with a water reservoir assembly comprising: - a water reservoir (110) having a movable wall (112b) allowing variation of a water volume - a pressurization device (120) with a pressurization cylinder (120a) wherein a piston (121) is reciprocable defining first (122) and second (123) chambers, wherein the piston (121) is movable in response to a difference in gas pressure between the first chamber (122) and second chamber (123), and - a connector structure (130) that connects the movable wall (112b) of the water reservoir (110) to the piston (121) of the pressurization device (120). The pressurization device (120) pressurizes water that is discharged from the water reservoir.

Description

TOY WATER GUN The present invention relates to the field of toy water guns.

A first aspect of the invention relates to a toy water gun with a water reservoir assembly having a variable water volume. In the field toy water guns are known having an expandable water reservoir that is expandable by the pressure exerted on the water reservoir by the water received in the reservoir. Such expandable water reservoirs allow the storage of pressurized water in the toy water gun. The pressurized water may be pressurized by the user of the toy water gun, e.g. by a suitable pump provided within or separate from the toy water gun. The provision of pressurized water and a water reservoir expandable in response to said pressurized water allows for the discharge of a more powerful water stream that can traverse a larger distance.

US2005072794 describes an expandable water reservoir in a toy water gun. In particular this document discloses a toy water gun comprising a water reservoir, wherein a water volume in said water reservoir is enclosed by a cylinder and a water piston that is reciprocable in the cylinder. The water piston forms a movable wall allowing to enlarge and reduce said water volume. This water piston is movable in response to pressure exerted thereon by pressurized water present in the water reservoir. The water volume can be enlarged against an air pressure that directly acts on the opposite side of the water piston. When the discharge of water from the water reservoir is enabled the air pressure aids in forcing the water out of the water reservoir. The air pressure is formed in a dedicated chamber and can be further pressurized by means of an air pump to reach a pressure in the pressure chamber that exceeds atmospheric pressure.

A first aspect of the invention aims to provide an improved toy water gun, or at least an alternative for existing toy water guns and provides a toy water gun according to claim 1. Herein the pressurization device is embodied such that, when discharge of water from said water reservoir is prevented by the discharge valve and pressurized water is being fed into said water reservoir via the inlet thereof, the pressurized water exerts a force on the movable wall of the water reservoir so as to enlarge said water volume, which in turn causes enlargement of the volume of the first chamber of said pressurization device and reduction of the volume of the second chamber of the pressurization device thereby the gas pressure in the first chamber becoming lower than the gas pressure in the second chamber thereof thus exerting a force on the piston so as to reduce the volume of the first chamber which is transmitted via the connector structure, e.g. piston rod, to the movable wall so as to pressurize the water in the water reservoir. When discharge of water from said water reservoir is subsequently enabled by said discharge valve, the pressurization device pressurizes said water that is discharged from the water reservoir.

The inventors have determined that the expandable water reservoir of

US2005072794 has disadvantages. The force provided to the water volume by the air pressure is determined by the pressure difference between the water volume and the air pressure in said chamber and by the area of the movable piston. As the area of the movable piston of US2005072794 is limited, a large pressure difference is needed to obtain a sizeable force. However, a simple and affordable air pump may not be able to provide such high air pressure, and thus the device of US2005072794 may not be able to provide the desired force to the water volume.

In embodiments of the present invention, the provision of a water reservoir with a movable wall one the one hand and of a pressurization cylinder with a piston on the other hand, wherein said movable wall is connected by a connecting structure to the piston, allows the provision of a piston in the pressurization device that has a larger cross-sectional area than the movable wall of the water reservoir. Due to this larger cross-sectional area the force exerted by the pressurization device as a result of the pressure difference between the first and the second chambers can be larger. This larger pressure difference contributes to a more powerful discharge stream that can traverse larger distances.

The area of the piston of the pressurization device may e.g. be two or more times larger than the area of the movable wall of the water reservoir acting on the water, e.g. four or more times larger.

The volume of the pressurization cylinder may be e.g. two or more times larger than the largest water volume that can be reached through moving said movable wall of the water reservoir, e.g. four or more times larger.

The movable wall of the water reservoir may be provided with one or more resilient seals, e.g. one or more O-rings extending around a water piston.

The piston of the pressurization device may be provided with one or more seals, e.g. one or more O-rings extending around the piston, to prevent gas flow between the first chamber and second chamber of the pressurization device.

According to the first aspect of the invention, the first and second chambers contain a gas, preferably air, possibly very little gas as will be explained herein.

In a preferred embodiment the second chamber is in communication with ambient, whereas the first chamber is at a pressure below atmospheric pressure, at least in some operative positions of the piston. In another embodiment the second chamber is at a pressure above atmospheric pressure, at least in some operative positions of the piston, e.g. with the first chamber being at a pressure below atmospheric pressure, at least in some operative positions of the piston. In an embodiment of the invention a partial vacuum is provided in the first portion of said pressurization chamber, e.g. said partial vacuum already being present when no or minimal water is present in the water reservoir and/or said partial vacuum being created when water is fed into said reservoir causing the piston of the pressurization device to move and thus create a below atmospheric pressure.

In all practical embodiments, even those with a partial vacuum, some gas, e.g. air, molecules will be present in the first chamber, and thus the first chamber is the considered to be filled with a gas or to contain a gas in the context of this first aspect of the invention. The phrasing 'filled with a gas' thus includes all gas pressures obtainable in practice in a toy water gun and does not exclude low pressures.

In a preferred embodiment the second chamber is at all times in communication with the ambient air. In this embodiment the pressure in the first chamber will, possibly dependent on the position of the piston, be different from ambient air, so as to provide the desired pressure difference between the two chambers.

In an embodiment the volume of the water reservoir is substantially zero when no water is provided to the water reservoir, so the reservoir is totally empty.

In an embodiment, with the water reservoir being empty or at lowest effective volume during use, the volume of the first chamber is substantially zero.

The movable wall of the water reservoir is in an embodiment made to rest against one of the other walls, e.g. an end of a water cylinder forming the water reservoir, when no water is present in the water volume. This embodiment may be realized by a suitable choice of the length of the connector structure, e.g. a rigid elongate element, and the distance between the water reservoir and the pressurization device. In this embodiment the water reservoir and pressurization device will upon discharge of water from said water reservoir return to said substantially zero volume. Thus, the water volume may be emptied completely when discharge of water is enabled.

The relative increase in volume of the first chamber during enlargement is largest when the volume thereof is initially substantially zero, so that the ratio of initial volume of the first chamber, that is, the volume when no or minimum water is present in the water reservoir, to an enlarged volume, is the largest. As the change of volume during enlargement is maximized, also the change in pressure in the first chamber of the pressurization is maximized, thus creating a larger force that will be exerted on the piston and the water in the water storage volume of the water reservoir when discharge of water from the water reservoir is enabled. In an embodiment the pressurization device is embodied such that a partial vacuum in the first chamber is such that the pressure difference between the first and second chambers is substantially independent of the position of the piston. As a result the force provided by said pressure difference is independent of the position of the piston in the pressurization cylinder, e.g. said pressure difference between the first and second chambers does not differ by more than 20% between different terminal positions of the piston.

In an embodiment the first chamber is well-sealed from its surroundings, such that a partial vacuum can be maintained in said first chamber with a pressure that is sufficiently low to maintain a pressure difference between the first and second chambers that is substantially independent of the operative positions of the piston. The pressure of the second chamber may be substantially ambient pressure.

Embodiments of the invention allow to overcome a disadvantage of existing expandable water reservoirs, such as the abovementioned US2005072794. A disadvantage of US2005072794 is that as the volume of the air pressure chamber increases during discharge, the pressure of the air pressure chamber, and subsequently the pressure difference between water storage volume and air pressure chamber, decreases. As a consequence, the force provided by said movable wall and therefore the distance that the discharge stream of the water toy gun can traverse decreases during a discharge.

In the abovementioned embodiment of the invention the force provided by the gas pressure difference is essentially independent of operative positions of the piston, and thus it is expected that the force exerted by the movable wall of the water reservoir on the water in said reservoir is essentially independent of operative positions of the piston. Thus, the pressure of the water stream that is discharged by the toy water gun and the distance that the water stream may traverse is expected to remain substantially constant throughout a discharge.

In an embodiment the second chamber is in communication with the ambient air by means of a passage extending through a wall of the pressurization device. One could also envisage such communication via the connector structure, albeit believed to be more complex.

In an embodiment an ambient pressure passage, or venting passage, of a chamber of the pressurization device is provided with an airflow operated sound-producing device that is adapted to provide a sound having a first frequency spectrum that is at least partially audible with the human ear when, in response to the motion of the piston upon enabling the discharge of water from the water reservoir, an air flow occurs through said passage from the ambient to the chamber. In this embodiment the discharge of water from the toy water gun is accompanied by a sound mechanically produced by an air flow that occurs through this passage. The sound may e.g. be a flute-like sound with higher tones and/or a horn-like sound with lower tones.

In an embodiment the pressurization device further comprises an exterior protrusion, e.g. at the exterior side of the wall of the cylinder through which the passage extends. Said protrusion may be provided around the passage. The protrusion is shaped to further facilitate the creation, amplification, and/or spreading of the airflow induced sound, e.g. horn- shaped.

In an embodiment of the invention, the pressure in the second portion of the pressurization chamber is above atmospheric pressure in one or more operative positions of the piston, e.g. always. In this embodiment the piston is thus during the expansion or filling of the water volume moved against the above atmospheric pressure of the chamber. In such an embodiment the pressure in the first chamber may be substantially at atmospheric pressure, possibly in communication with ambient air, or below atmospheric pressure.

In an embodiment the water reservoir has a water reservoir cylinder forming a wall of said water reservoir, and a water piston that is reciprocable within said water reservoir cylinder and forms said movable wall of said water reservoir. The opposite side of the water piston may be exposed to ambient pressure as is preferred. In an embodiment a spring may act on said opposed side of the piston.

In an embodiment the piston of the pressurization device and the water piston of the water reservoir are aligned on a common axis, e.g. a common horizontal axis. For example these pistons are directly connected to one another via a rigid structure, e.g. an elongated piston rod.

In an embodiment the toy water gun further comprises a water storage container, preferably an ambient pressure water storage reservoir that store a water volume at ambient pressure. In an embodiment the storage container of the water gun is adapted to store a volume of water that is significantly greater than the maximum water reservoir volume, e.g. at least 10 times greater than said water reservoir volume.

In an embodiment a water storage container is permanently integrated with the toy water gun or releasably mounted to the toy water gun. For example the water storage container has a fill opening for filling the water storage container with water, e.g. from a tap. In an embodiment the toy water gun comprises a water pump integrated with the toy water gun, e.g. an electric motor driven water pump or a manually driven water pump.

In an embodiment the water pump has a pump inlet and a pump outlet, wherein the inlet of said water pump is in communication with a water storage container, and wherein the pump outlet of said water pump is in communication with the inlet of the water reservoir, so as to be able to provide pressurized water to said water reservoir. In an embodiment a water duct extends between a combined inlet and outlet, e.g. a single aperture of the cylinder of the water reservoir, on the one hand and the water discharge valve on the other hand. In an embodiment the pump outlet is connected to this water duct so that with the pump in operation and said valve closed, pressurized water is fed to the water reservoir, e.g. from a storage container of the toy water gun.

In an embodiment said toy water gun may further comprise a water storage container and a pump. Said pump preferably has an inlet and an outlet, wherein the inlet of said pump is in communication with said water container, and wherein the outlet of said pump is in communication with the water storage volume of the water reservoir of the expandable water reservoir, so as to be able to provide pressurized water to said water storage volume of the expandable water reservoir. The pump may be a manually operated pump.

The toy water gun may further comprise an activator for an electric motor driven pump, e.g. a press button or switch, that can be activated, e.g. pressed or pulled, by a user to start operation of the pump.

The toy water gun may further comprises an electrical pump drive, e.g. including a battery, e.g. a rechargeable battery, to drive operation of the pump. This rechargeable battery may be similar to the batteries provided to a handheld electric tool, such as a drill.

The toy water gun may further comprise a water fill inlet, said water fill inlet in communication with the water storage container.

The toy water gun may further comprise an outlet nozzle, said outlet nozzle in communication with the water reservoir, e.g. by means of a conduit or duct, e.g. a hose.

The toy water gun may comprise a trigger, said trigger movable by a user between a holding position and a discharge position. In addition, the toy water gun may comprise a discharge valve that is adapted to move from a closed position to an open position in response to a movement of the discharge control from the holding position to the discharge position.

The discharge valve may be provided in a conduit provided between the water reservoir and an outlet nozzle. Said discharge valve in the open position allows water to flow to the outlet nozzle, and prevent said water flow in the closed position.

In an embodiment the water reservoir comprises a separate inlet and outlet, e.g. a separate inlet and outlet conduit connected and in communication with said water reservoir. Said inlet and outlet may each be provided with a valve that controls the passage of water.

In another embodiment the water reservoir comprises a single combined inlet and outlet, e.g. a conduit that acts as inlet and outlet. This combined inlet and outlet may be provided with a valve to control the passage of water. The walls of the water reservoir may comprise plastic. This may be rigid, non- deformable plastic, e.g. for one or more fixed walls. An elastomer may for example be used for any seals between the fixed wall(s) and movable wall.

Similarly, the pressurization device may comprise plastic, which may be non- deformable plastic.

The connector structure may comprises plastic, e.g. a rigid elongate element may comprise plastic, but may e.g. also comprise metal to strengthen said elongate element.

In an embodiment the cylinder of the pressurization device is made at least in part transparent, e.g. of transparent plastic, e.g. coloured transparent plastic, allowing a user to witness the travel of the piston therein, thereby enhancing the user experience of the toy water gun.

The first aspect of the invention also relates to a toy water gun comprising:

- a water discharge outlet,

- a discharge valve controlling discharge of water from said water discharge outlet, e.g. a trigger controlled discharge valve,

- a water reservoir having an inlet and an outlet, said water reservoir comprising a water cylinder and a reciprocable water piston in said cylinder enclosing a variable water volume in said water reservoir,

- a pressurization device comprising a pressurization cylinder, wherein a piston is reciprocable in said pressurization cylinder and defines in said cylinder a first chamber and a second chamber on opposite sides of said piston, wherein said first and second chambers are filled with a gas, e.g. air, wherein said piston is movable in response to a difference in gas pressure between the first chamber and second chamber, and

- a connector structure, e.g. a piston rod, that connects the water piston of the water reservoir to the piston of the pressurization device,

wherein said pressurization device is embodied such that, when discharge of water from said water reservoir is prevented by said discharge valve and pressurized water is being fed into said water reservoir via the inlet thereof, said pressurized water exerts a force on said water piston so as to enlarge said water volume, which in turn causes enlargement of the volume of the first chamber of said pressurization device and reduction of the volume of the second chamber of said pressurization device thereby the gas pressure in the first chamber becoming lower than the gas pressure in the second chamber thereof thus exerting a force on said piston so as to reduce the volume of the first chamber which is transmitted via said connector structure to said water piston so as to pressurize said water in said water reservoir, such that when discharge of water from said water reservoir is subsequently enabled by said discharge valve, said pressurization device pressurizes said water that is discharged from said water reservoir. The first aspect of the invention also relates to a toy water gun with a water reservoir assembly comprising:

- a water reservoir having a movable wall allowing variation of a water volume

- a pressurization device with a pressurization cylinder wherein a piston is reciprocable defining first and second chambers, wherein the piston is movable in response to a difference in gas pressure between the first chamber and second chamber, and

- a connector structure that connects the movable wall of the water reservoir to the piston of the pressurization device.

The pressurization device pressurizes water that is discharged from the water reservoir. The present invention also relates to a method to store pressurized water, wherein use is made of a toy water gun according to the disclosure.

According to a second aspect, the invention relates to a toy water gun comprising a water discharge outlet and a discharge valve controlling discharge of water from said water discharge outlet, e.g. a trigger controlled discharge valve.

Sound-producing elements comprised in toy water guns are known. These are for instance electrical units, possibly battery-powered, that e.g. produce machine gun sound effects together with the discharge of water. Also units producing sound through mechanical motion of components are known, e.g. from US4757946, GB1063146 and US5662244. The creation of sound is in these prior art sound-producing elements induced by the movement of the trigger of the toy water gun.

It is an object of the second aspect of the invention to provide an alternative sound- producing device in a toy water gun.

According to the second aspect of the invention a toy water gun according to claim 15 is proposed. Possible advantages of said sound-producing design according to the invention are that no batteries are needed for production of the sound, and that no complex and/or costly moving elements are needed, thereby saving costs and/or reducing the chance of malfunctioning/failure of the sound-producing element.

Whereas in the toy water guns of the prior art the sound-producing element is generally mechanically operated or electrically activated by the pulling of the trigger, in the invention the sound is produced as a result of an airflow caused by water discharge, e.g. as a water reservoir in the water gun is then reduced in volume and the variable volume chamber is simultaneously increased in volume so that air streams through the passage and the sound- producing device.

In an embodiment the toy water gun comprises an expandable water reservoir, that is expandable from a relaxed state occupying a relaxation volume to an expanded state occupying an additional expansion volume, and compressible from said expanded state occupying said additional expansion volume back to said relaxed state occupying said relaxation volume, e.g. said reservoir having a resilient material body that is internal water pressure expandable and self-compressing, wherein the toy water gun further comprises a housing, and wherein said variable volume chamber is delimited between said housing and said expandable water reservoir, wherein said housing is provided with said passage and said sound-producing device is adapted to provide said water discharge related sound as in response to the compression of the expandable water reservoir from the expanded state to said relaxed state an air flow occurs through the passage from the exterior into said variable volume chamber.

In an embodiment the toy water gun comprises a pressurization device comprising a pressurization cylinder, wherein a piston is reciprocable in said cylinder and defines in said cylinder a first chamber on one side of said piston and a second chamber on the opposite side of said piston, wherein said first and second chambers are filled with a gas, e.g. air, wherein said piston is movable in response to a difference in gas pressure between the first chamber and second chamber, and wherein one of said chambers is in communication with the ambient air by means of a passage extending through a wall of said cylinder, wherein said passage is provided with said airflow operated sound-producing device being adapted to provide a sound having a first frequency spectrum that is at least partially audible with the human ear when, in response to the discharge of water from the toy water gun, an air flow occurs through said sound-producing device from the ambient to said chamber. Said pressurization device may be part of a toy water gun having one or more details as described in the first aspect of the invention.

In an embodiment a sound-producing housing is provided around an expandable water reservoir. The expandable water reservoir is in such an embodiment expandable in response to a pressure exerted thereon by water, e.g. pressurized water, received within said reservoir and compressible from said expanded state occupying said additional expansion volume back to said relaxed state occupying said relaxation volume upon discharge of said water from said reservoir.

In an embodiment a sound-producing housing can alternatively be provided around an expandable gas, e.g. air, reservoir. In an embodiment, the frequency of the discharge sound is dependent on the rate of discharge of water from the toy water gun, e.g. from said expandable reservoir. The rate of discharge from said expandable reservoir determines the rate of compression of said expandable reservoir, which in turn determines the rate of air flow through the passage. When said rate of air flow changes, the frequency of the accompanying sound may be altered.

In an embodiment the sound-producing device is also adapted to provide a filling sound having a frequency spectrum that is at least partially audible with the human ear when during filling of a water reservoir of the water gun, e.g. expansion of the expandable reservoir, an air flow occurs through the passage. In an embodiment said airflow during filling is opposite in direction to said airflow during water discharge, said difference in direction causing different sounds for discharge and filling. In another embodiment two distinct sound- producing devices are present, one responsive to and operated by an airflow related to water discharge and the other response to and operated by an airflow related to filling of a water reservoir of the toy water gun. In embodiments the discharge sound and the filling sound are different, e.g. said filling sound may have a frequency spectrum different from the discharge sound.

In an embodiment, the toy water gun comprises an external protrusion on the exterior thereof. Said protrusion may be provided around the passage so as to extend said passage. In embodiments said protrusion facilitates the provision, creation, amplification, and/or spreading of said sound, produced by said sound-producing device, e.g. during discharge of water, optionally also when filling with water, e.g. said protrusion being horn-shaped or flute- shaped.

In an embodiment a housing of the toy water gun comprises a common attachment portion, wherein a first airflow operated sound-producing device is detachable from and attachable to said common attachment portion, and wherein a second airflow operated sound-producing device is provided that is exchangeable for said first airflow operated sound-producing device and also is detachable from and attachable to said common attachment portion, e.g. said first and second airflow operated sound-producing devices having different sounds.

The sound-producing device may for instance comprise a portion of the housing around the passage and/or a protrusion, e.g. a horn-shaped protrusion.

Said first and/or second sound-producing device may be detachable and attachable by e.g. a click-system, e.g. by the provision of threaded end portions to the attachment portion and detachable device , e.g. by a bayonet mount. The second aspect of the invention also relates to a sound-producing system for use with a toy water gun according to claim 16. The sound-producing system thus comprises a second sound source, that may in an embodiment be used to replace the first sound source and vice versa. In this way, a user may choose a sound that he/she likes, or may choose the same sound as other users of the sound-producing housing have chosen, so as to form a team that uses the same sound.

Said second device may, similar to the first device be detachable and attachable by e.g. a click-system, by the provision of threaded end portion, by a bayonet mount, to the common attachment portion.

The second aspect of the invention also relates to a method to provide sound to a toy water gun, said method making use of a toy water gun according to the disclosure.

According to a third aspect the invention relates to a toy water gun with a pulsating discharge mode. Pulsating toy water guns are known in the art, e.g. from US20080277413 and US6123229.

US20080277413 discloses a toy water gun comprising an inlet for water, a first water reservoir in communication with said inlet and an outlet nozzle, wherein said nozzle is in communication with the first water reservoir through a conduit. US20080277413 furthermore discloses a pressurized second water reservoir in communication with the conduit and provided between the first water reservoir and the outlet nozzle and a trigger movable by a user between a holding position and a discharge position. In addition, US20080277413 discloses a discharge valve provided in the conduit between the first water reservoir and the second water reservoir, wherein said discharge valve is adapted to move from a closed position to an open position in response to a movement of the trigger from the holding position to the discharge position, wherein said discharge valve in the open position allows water to flow to the second water reservoir. The toy water gun of US20080277413 is adjustable by a user to a pulsed-mode setting wherein, when the first water reservoir has been filled with a water and the trigger is moved to and kept in the discharge position, the pressure of water in the conduit is such that the self-closing outlet nozzle only opens when the second water reservoir is filled, e.g. partially filled, with the water from said first water reservoir. Moreover, upon opening of the outlet nozzle at least part of the water in the second water reservoir is discharged through said outlet nozzle, after which discharge the second water reservoir is again filled with water from the first water reservoir, and wherein a repetition of said filling and discharging creates a pulsed discharge of water through said outlet nozzle. US6123229 discloses a toy water gun with a pulsating discharge mode comprising a self-closing outlet nozzle.

According to the third aspect of the present invention, a toy water gun is provided according to claim 17.

The inventors have realized that a drawback of US2008/0277413 is that the discharge valve is provided between the first and the second reservoir. As a result of this positioning of the discharge valve, after the trigger has been moved to and kept in the discharge position the second reservoir first has to be filled before water can be discharged from the outlet nozzle.

In the toy water gun according to this invention the discharge valve is provided in between the second water reservoir and the self-closing nozzle. Consequently, the second water reservoir can already be sufficiently, e.g. completely, filled before said discharge valve is moved to the open position, thereby allowing a more rapid response of the toy water gun upon movement of the trigger to the discharge position.

The self-closing nozzle of the toy water gun according to this invention may, as is preferred, exhibit hysteretic behaviour, in that the nozzle remains closed at a certain first pressure, opens at a critical pressure that exceeds that first pressure, but then remains open at a range of pressures below said critical pressure. In this way the pressurized second reservoir can first be filled, wherein the self-closing outlet nozzle remains closed, and can subsequently be emptied, wherein during the discharge of the pulse of water the self-closing nozzle remains open.

In an embodiment the toy water gun further comprises pressurization means to pressurize the water in said conduit, wherein said pressurization means are embodied to pressurize water in said first water reservoir or in said conduit between the first reservoir and the throttle component. As an example the pressurization means may be embodied as a water pump provided in the conduit in between the first water reservoir and the throttle component. As another example the pressurization means may be provided by embodying said first water reservoir as a pressurized water reservoir, e.g. an air pressure pressurized water reservoir, e.g. with an air pump to pressurize air in said water reservoir.

The term 'pressurized water reservoir' here in the third aspect of the invention indicates that the reservoir is able to maintain, e.g. partly maintain, the above atmospheric pressurization of the water that is provided to the water reservoir or that further pressure may be built in the reservoir. Concerning the latter embodiment, the pressurized water reservoir may be an expandable water reservoir, e.g. expanding a water volume against a movable wall, piston or elastomeric material, as said ability to expand preserves the pressure provided to the water. Concerning the former embodiment, further pressure may be built e.g. by the insertion of gas to a reservoir with a fixed volume. The addition of said gas increases the pressure of the water in said reservoir, thereby creating a pressurized water reservoir.

The inlet for water may e.g. be an aperture that can be sealed by a cap. Said inlet may be provided directly on the first water reservoir, but can also be provided at a distance from said first water reservoir and in communication with said first reservoir, e.g. by a conduit. The inlet may be connectable to a standard type nozzle of a water hose.

The first reservoir may be a plastic, non-deformable reservoir. It may be provided with a water level indicator or it may be partly transparent so as to allow a user to see the water level in the reservoir.

In an embodiment the first water reservoir is embodied as a first expandable water reservoir expandable in response to a pressure exerted thereon by a pressurized water received in said reservoir, e.g. said first water reservoir being embodied as an expandable body, e.g. a bladder, e.g. comprising a resilient, e.g. elastomeric material, body.

In an embodiment the pressurized second water reservoir is an expandable second water reservoir expandable in response to a pressure exerted thereon by pressurized water received in the second reservoir, e.g. the second water reservoir being embodied as an expandable body, e.g. a bladder, comprising a resilient, e.g. an elastomeric material, body. In an embodiment the toy water gun comprises a water reservoir assembly according to the first aspect of the invention, wherein said water reservoir of said assembly forms the pressurized second water reservoir.

In an embodiment the self-closing outlet nozzle is embodied such that in the pulsed- mode setting of the throttle component the self-closing outlet nozzle closes to end discharge of a water pulse only when the second water reservoir has become substantially empty of water, e.g. when at least 80% of the water that was in the second water reservoir has been expelled.

In an embodiment the self-closing outlet nozzle is embodied such that in the pulsed- mode setting of the throttle component the self-closing outlet nozzle only opens when the second water reservoir has been fully replenished with water and the second water reservoir has expanded in response to the pressure exerted thereon by the water received in the second water reservoir.

The self-closing nozzle may be self-closing through the use of suitable flexible material of which said nozzle is formed, or by use of a flexible material in combination with a (metal or plastic) springs or other resilient elements.

The throttle component may be embodied for adjustment by a user. The throttle component may be adjustable to two settings or more than two settings, e.g. four settings. Said throttle component may be continuously adjustable between two extreme settings. The trigger may be embodied as a trigger of a gun, that is, as an movable element that a user can pull backward with one of its fingers to initiate a discharge. However, the trigger may also be differently shaped, for instance as a push button or a pinchable object.

The trigger controls the discharge valve by suitable means, e.g. electrically, e.g. mechanically through a linkage, e.g. a rigid element or through a rope connected to the trigger and discharge valve. Said discharge valve may e.g. be a ball valve, a butterfly valve or a gate valve.

In an embodiment the pressurized second water reservoir is an expandable second water reservoir expandable in response to a pressure exerted thereon by pressurized water received in said second reservoir, e.g. said second water reservoir being embodied as an expandable bladder comprising an elastomeric material.

In another embodiment the pressurized second water reservoir is a embodied as part of the water reservoir assembly that has been disclosed herein as encompassing said water reservoir, a pressurization device and a connector structure, wherein the discharge of water from said water reservoir is prevented and enabled by the self-closing nozzle valve. Thus, the water reservoir and any related features according to the first aspect of the invention may be included in the toy water gun according to the third aspect of the invention.

In an embodiment the communication of the second water reservoir with the conduit is provided by a single connector conduit that serves both as an inlet and as an outlet to the second water reservoir. The provision of a single connector conduit facilitates the design of the pressurized second water reservoir.

In an embodiment the self-closing outlet nozzle is in the pulsed-mode setting of the throttle component adapted to close after a discharge of water only when the second water reservoir is substantially empty of water, e.g. when at least 80% of the water that was in the second water reservoir has been discharged. To this end the self-closing outlet may be adapted by a suitable choice of materials.

In an embodiment in the pulsed-mode setting of the throttle component the self- closing outlet nozzle only opens when the second water reservoir is fully filled with water and the second water reservoir has expanded in response to the pressure exerted thereon by the water received in the second water reservoir. This behaviour may be realized by a suitable choice of self-closing outlet nozzle and expansion characteristics of the second water reservoir.

In an embodiment the throttle component provides for and can be brought into a continuous-mode setting wherein, when the first water reservoir has been filled with a water and the discharge control is moved to and kept in the discharge position, the pressure of water in the conduit is such that the self-closing outlet nozzle is in response to the pressure exerted thereon by the water from said first water reservoir continuously open, so as to create a continuous discharge of water through said self-closing outlet nozzle. In this embodiment the discharge of water occurs both in the pulsed-mode setting and in the continuous-mode setting through the same self-closing outlet nozzle. Thus, in the pulsed- mode setting and in the continuous-mode setting the water follows substantially the same flow path through the toy water gun.

In an embodiment the self-closing outlet nozzle is embodied as a unitary self-closing outlet nozzle, e.g. with a slit valve.

For example the self-closing outlet nozzle is embodied with a resilient material self- closing outlet nozzle, e.g. as a duckbill valve, a slit valve, etc..

The third aspect of the invention also relates to a method to discharge water from a toy water gun in a pulsating manner, wherein said method makes use of a toy water gun according to the disclosure. A fourth aspect of the invention relates to a toy water gun system comprising a toy water gun and a filling station.

Toy water gun systems comprising a toy water gun and a filling station are known in the art, e.g. from US20100269953. This document discloses a toy water gun system comprising a toy water gun and a filling station. The toy water gun comprises a water reservoir, a water inlet to provide water to said water reservoir, an outlet nozzle in

communication with said water reservoir and a discharge control operable by a user to allow water to be controllably discharged from said water reservoir via said nozzle. The filling station comprises a water inlet and a water outlet in communication with said inlet. The water inlet of the toy water gun is attachable to said water outlet of the filling station so as to allow communication between said water outlet and water inlet, and wherein said water inlet of the toy water gun is detachable from said water outlet.

In operation a water hose that is connected to the water mains is connected to the water inlet of the filling station of US20100269953. The device of US20100269953 can thus be used together with a water hose and while in the vicinity of a water mains connection. The filling station does not comprise any pressurization means, such as a water pump, so that the pressure of the water in the filling station and in the toy water gun is limited to the pressure provided by the water mains.

The present invention aims to provide an improved toy water gun system comprising a toy water gun and a filling station.

According the fourth aspect a toy water gun system according to claim 19 is provided, wherein said toy water gun system comprises a toy water gun and a filling station. In the toy water gun system according to this invention a water pump is provided in the filling station, so that water provided to said filling station can be pressurized to a pressure that is higher than the pressure of the water at the water inlet of the filling station. Thus, said toy water gun systems allows use of toy water guns comprising an expandable water reservoir that require a high water pressure to produce a powerful discharge stream that can traverse a long distance.

In an embodiment said filling station further comprises a water tank adapted to store therein unpressurized water. Said water tank is provided in between the water inlet and the inlet of the water pump and said water tank is in communication with the water inlet and with the pump. This embodiment allows use of the toy water gun system with unpressurized water. Said water may be provided to the water tank of the filling station e.g. with a water hose or with a bucket. Moreover, said water tank may be filled before transporting, e.g. carrying, the filling station to its operational location, that is, its location during the use of the toy water guns in e.g. a water fight. The filling station may however also be filled at the operational location.

In another embodiment the water inlet is connectable to a water hose. The pump may in this embodiment act to increase the pressure of the incoming water if said pressure of the incoming water is insufficient for the operation of the toy water gun.

In an embodiment water can be discharged from the toy water gun while said toy water gun is detached from the filling station. Thus, after water has been provided from the filling station to the expandable water reservoir, the toy water gun may be detached to allow a user to move around freely with said toy water gun, while said filling station remains at its operational location.

In an embodiment the electrical drive of the water pump of the filling station comprises a battery, preferably a rechargeable battery. The provision of the battery allows the filling station to be placed at any convenient operational location, without the need for a connection to the power mains. Preferably the rechargeable battery is readily disconnectable from the filling station for remote charging in a charging station.

In an embodiment the filling station further comprises a housing. The water reservoir and water pump of the filling station are provided substantially within said housing, wherein said water outlet of the filling station extends at least partially from said housing.

In an embodiment the water outlet of the filling station comprises a connector tube that extends from said housing. Said connector tube has a pump end in communication with said pump and a water gun end to which said toy water gun can be attached. The connector tube may be short, e.g. 10 to 30 cm, but may also be longer, e.g. one to two meters, so as to allow a user to discharge water from said toy water gun while it is attached to the filling station. In an embodiment the filling station further comprises an activator. When said toy water gun has been attached to said water outlet of the filling station, the water pump upon operation of the activator pressurizes water that has been provided to the filling station. The activator may e.g. be a push button that starts operation of the pump. The provision of the activator allows one to operate the pump only when needed.

In an embodiment the filling station is portable, e.g. by means of one or more carrying grips provided to the filling station, e.g. to the housing thereof, and/or the station having wheels.

In an embodiment the tank of the filling station is portable. The tank is attachable to and detachable from other components of the filling station, e.g. a pump carrying base of the filling station. In this embodiment, only the tank of the filling station has to be transported, e.g. carried, to a filling location, e.g. a connection to the water mains, after which the tank can be brought to the location of the other components of the filling station and attached thereto in order to use said filling station.

In an embodiment the volume of the water tank of the filling station is multiple times the volume of the expandable water reservoir, e.g. ten times the volume of the expandable water reservoir, e.g. five times the volume of the expandable water reservoir, e.g. three times the volume of the expandable water reservoir. Thus the provision of the filling station allows the water toy gun to be filled multiples times before the water tank is emptied, thereby allowing users to enjoy their play for a longer time, as no interruptions to fill said toy water gun at a remote filling location are needed. Instead, the toy water gun can be filled at the - presumably nearby - filling station, which forms only a short interruption.

The tank of the filling station may have a volume between 1 and 25 L, e.g. 2 L, e.g. 5 L. Tanks having a volume larger than 10 L may be preferred in combination with multiple toy water guns. Such large tanks are envisioned to be filled at the operation location.

In an embodiment the expandable water reservoir of the toy water gun is part of a water reservoir assembly according to the first aspect of the invention, which comprises a water reservoir, a pressurization device, and a connector structure. Thus, at least the first aspect of the invention can be included in the fourth aspect thereof.

The fourth aspect of the invention also relates to a method to fill a toy water gun, wherein said method makes use of a toy water gun system according to the disclosure, wherein said method comprises the steps of filling the water reservoir of the filling station with water and attaching the toy water gun with the water inlet thereof to the water outlet of the filling station, and optionally operating said activator, so that water from the water reservoir of the filling station is pressurized by the pump and is subsequently provided via the water outlet of the filling station and the water inlet of the toy water gun to the expandable water reservoir of the toy water gun.

The expandable water reservoir according to the first aspect of the invention and/or the sound-producing designs according to the second aspect of the invention can be included in the toy water gun with pulsed-mode setting according to the third aspect of the invention and in the toy water gun system according to the fourth aspect of the invention. In addition, the toy water gun with pulsed-mode setting according to the third aspect of the invention can be included in the toy water gun system of the fourth aspect of the invention.

A fifth aspect of the invention relates to a toy water gun system comprising:

- a handheld toy water gun comprising:

- a water circuit comprising:

- a water discharge outlet,

- a discharge control operable by a user allowing water to be controllably discharged from said water reservoir via said water discharge outlet,

- a first connector having an inlet of said water circuit,

- a cartridge having a cartridge housing and being provided with a water reservoir adapted to store a water volume therein, e.g. a pre-pressurizable water reservoir adapted to store water therein under pressure, said cartridge further being provided with a second connector having a water port of said water reservoir,

wherein said cartridge is releasably connectable to said toy water gun and said first and second connectors are connectable to one another so as to establish a connection between the water port of the water reservoir of the cartridge and the inlet of the water circuit of the handheld to water gun,

wherein, optionally said first connector is provided with a first valve assembly, wherein said optional first valve assembly is adapted to close said inlet of said water circuit in case said cartridge is disconnected from the toy water gun, and to open said inlet of said water circuit in case said cartridge is connected to said toy water gun,

and wherein said second connector is provided with a second valve assembly,

wherein said first and second connectors are adapted to be connected to one another by advancing the cartridge along a connection axis relative to the toy water gun into an advanced position of the cartridge and to be disconnected from one another to be retracting the cartridge along said connection axis.

Examples of a toy water gun systems with pre-pressurizable water reservoir cartridges are for example shown in US6345732. The fifth aspect of the invention aims to propose improved toy water gun systems provided with one or more exchangeable cartridges, e.g. in view of user comfort and/or user experience, etc. The fifth aspect of the invention provides a toy water gun system according to claim 20.

By provision of the rotary valve in the cartridge several advantages and/or user experiences can be achieved, e.g. compared to prior art designs wherein axially connecting the first and second connectors opens the cartridge valve. For example such prior art designs require basically that the user opens the valve against the pre-pressurized water in the reservoir if such reservoir is present and filled.

In the inventive design, the opening of the rotary valve requires some rotational motion, distinct from an axial advancing motion. This rotational motion is not impaired, in suitable designs, by an water pressure in the cartridge. Also, as will be explained here, the required additional rotational motion may allow for a bayonet connection that secures the cartridge to the toy water gun, so that the cartridge remains properly secured. Also, as will be explained here, the required additional rotational motion may allow for enhanced user experience, e.g. as in embodiments, the user may be forced to mimic the operation of the bolt handle of a gun, e.g. when connecting and disconnecting the cartridge from the toy water gun.

In an embodiment the toy water gun, e.g. the first connector, comprises a first coupling portion, wherein the rotary valve member comprises a second coupling portion which, when the rotary valve member is in said first angular position, is adapted to couple to said first coupling portion upon said axial advancing of the cartridge along a connection axis relative to the toy water gun into said advanced position, and wherein the toy water gun system is embodied to allow a user to manually cause said rotation of the rotary valve member from said first angular position into said second angular position only while said first and second coupling portions are coupled in said advanced position of the cartridge.

For example the first connector is stationary arranged on the toy water gun, with the first coupling equally stationary, e.g. at a front end of a male first connector. Herein, in an embodiment, the entire cartridge may be rotational relative to the water gun about the connection axis in order to open the rotary valve. For example the second connector is a female connector having a portion with a bore into which the male connector of the water gun is to be introduced.

In an embodiment the toy water gun comprises a bayonet structure with an L-shaped bayonet groove and a mating bayonet boss, wherein said groove has a longitudinal portion parallel to said connection axis and a locking portion at an end of said longitudinal portion and transverse to said longitudinal portion, wherein said bayonet structure is arranged such that, upon advancing said cartridge to said advanced position thereof, said boss slides through said longitudinal portion thereby preventing said manually caused rotation of the rotary valve member from said first angular position into said second angular position, and such that, upon having reached said advanced position of the cartridge and said user manually causing said rotation of the rotary valve member from said first angular position into said second angular position, the boss slides through the locking portion of the bayonet groove thereby opening the water port and preventing a retraction of the cartridge along said connection axis.

It will be appreciated that an axial locking of the cartridge relative to the water gun in its advance position may also be achieved through differently designed cooperating axial locking members. For example the water gun is provided with one or more spring detents engaging in a circular groove or groove sections on the cartridge when the cartridge is moved into its advanced position.

In embodiments the toy water gun comprises a cartridge carrier that is manually translatable along said connection axis and is adapted to receive said cartridge therein in a retracted position of said carrier and adapted to be translated together with the cartridge to said advanced position of the cartridge, preferably wherein the carrier comprises a receiving cradle onto which a portion of the cartridge is laterally insertable, perpendicular to said connection axis, said cradle retaining said portion in direction of said connection axis, preferably wherein the cartridge carrier is provided with a bolt handle for manual engagement by a user.

The provision of a cartridge carrier enhances the user experience when playing with the toy water gun. Also its provision may be beneficial in view of properly connecting and disconnecting the first and second connectors, e.g. avoiding undue loads being placed on the connectors by the user during these phases.

In preferred embodiments the cartridge carrier is manually rotatable about the connection axis when said cartridge is in said advanced position thereof. This design is advantageous in embodiments wherein said rotation of the carrier effects the opening, and in reverse direction the closing, of the rotary valve of the cartridge. The design is also advantageous in view of user experience, e.g. as a bolt handle present on the carrier now has to be moved similar to the bolt handle motion in an actual gun.

In embodiments an L-shaped bayonet groove is provided on the toy water gun, wherein a bayonet boss is provided on a cartridge carrier, wherein the cartridge is received in the carrier so as to be rotated along with the carrier.

In embodiments the toy water gun comprises a core member aligned with the connector axis and provided at one end thereof with said first connector, a water duct extending through said core member, wherein the toy water gun comprises a cartridge carrier which comprises an annular portion mounted over said core member and translatable along said core member.

In embodiments said core member is stationary mounted in the toy water gun and is provided with said L-shaped bayonet groove, and wherein said carrier is provided with said bayonet boss.

In embodiments said toy water gun has an external housing provided with an L- shaped bolt handle groove, with a longitudinal portion through which said bolt handle is slided by the user for advancing and retracting the carrier along said connection axis, and a transverse portion at an advanced position end of said longitudinal portion through which said bolt handle is slided by a user for rotating the carrier about said connection axis.

In embodiments said cartridge is provided with a pre-pressurizable water reservoir, e.g. with an expandable body, e.g. a body of resilient material, e.g. silicone rubber, that is expanded upon feeding pressurized water into said expandable body and that is self- compressing and/or the cartridge being provided with compression means associated with the water reservoir. For example the compression means may comprise one or more springs externally acting on the water reservoir, e.g. a spring acting on a piston of the water reservoir, e.g. external above atmospheric air pressure acting on a flexible water reservoir, etc.

In embodiments the first connector comprises a male connector and the second connector comprises a female connector having a bore wherein the male connector is insertable. This design allows for robustness of the cartridge in combination with relatively small dimensions, e.g. length, e.g. in an embodiment wherein the female connector at least in part extends into the water reservoir.

In embodiments the bore of the female connector is delimited by a tubular portion that stationary secured to the housing of the cartridge, wherein the rotary valve member is journalled externally about said tubular portion, wherein the tubular portion and said rotary valve are provided with radial ports that in said first angular position are out of alignment such that said rotary valve is closed and in said second angular position are aligned so that said rotary valve is open. Other designs of rotary valves are also possible, e.g. with a rotary valve member being arranged internally of a stationary part of the housing, e.g. with the rotary valve member forming the bore into which the male connector is to be inserted.

In embodiments the first valve assembly comprises an axially movable valve member that is urged, e.g. by a spring, into a closed position thereof, and that is pushed from said closed position as the cartridge is advanced into is advanced position. For example the axially movable valve member is a tubular member that is arranged around a male first connector of the toy water gun, said valve member closing on or more inlets in said male connector in its closed position. In embodiments the first valve assembly comprises a rotary first valve member that is rotatable about the connection axis between associated first and second angular positions to close and open an inlet of the first connector. For example the rotary first valve member is a tubular member arranged around a male first connector of the toy water gun. For example, upon advancing said cartridge into said advanced position thereof, the rotary valve member couples to the cartridge so as to rotated along with rotation of the advanced cartridge, e.g. thereby effecting simultaneous opening of the first and second valve assemblies as well as, when rotating in reverse direction, the closing thereof.

In general the provision of a first valve assembly allows to keep the toy water gun filled with water, even under pressure if no further water is discharged, e.g. during the disconnection of an empty cartridge and the placing of a full, preferably pressurized, cartridge.

In embodiments the toy water gun is provided with a water feed connector, e.g. a hose coupler, e.g. for a garden hose, connected to said water circuit, e.g. via a check valve, e.g. said water feed connector allowing to fill said cartridge when connected to the toy water gun.

One may also include in the system a filling station provided with a first connector, possibly with associated first valve assembly, that mates with the second connector of the cartridge. For example the filling station being a unit connectable to a water mains, e.g. to be connected to a water mains tap, e.g. via a garden hose. The filling station may also be embodied as described herein with reference to the fourth aspect of the invention.

In general the toy water gun of the fifth aspect of the invention may comprises one or more features as described herein with reference to one or more of the other aspects of the invention.

A sixth aspect of the invention relates to a toy water gun system according to claim 21. As explained herein above the provision of a cartridge carrier offers opportunities for advantages, such as avoiding undue mechanical forces (e.g. bending loads) on the connectors during connecting and disconnecting. It also allows to offer enhanced user experience, e.g. when providing a bolt handle to the carrier, e.g. allowing to mimic the bolt of an actual gun.

A seventh aspect of the invention relates to a toy water gun system according to claim 22.

An eight aspect of the invention relates to a toy water gun system according to claim

23. In this eights aspect of the invention it is envisaged that one toy water gun may be loaded with multiple cartridges, that are separately connectable and disconnectable from their first connector of the water gun whilst the one or more other cartridges remaining operational.

In embodiments each cartridge is axially locked relative to the toy water gun in the advanced position thereof, whilst rotational motion is possible so that the user, by rotation a selected cartridge, opens the rotary valve thereof and thus actively connects the water reservoir thereof to the water circuit. This will allow a user to choose which and/or how many, cartridges are actively connected to the water circuit. An empty cartridge can be shut whilst remaining in locked advanced position. A ninth aspect of the invention relates to a cartridge for use with a toy water gun having a water circuit according to claim 24.

A tenth aspect of the invention relates to a cartridge for use with a toy water gun having a water circuit according to claim 25. It will be appreciated that this cartridge is comprised in the second aspect of the invention and may be provided with one or more features as discussed with reference to said aspect. For example the airflow-operated sound producing device may be removably mounted, e.g. for exchange by another such device that produces another sound, e.g. allowing team players to have the same sound, e.g. distinct from the sound of an opposing player or team of players.

An eleventh aspect of the invention relates to a toy water gun water reservoir assembly as in claim 26.

The eleventh aspect also relates to a toy water gun water reservoir assembly, or to a toy water gun provided with a toy water gun reservoir assembly, which assembly comprises: - a variable volume water chamber having an inlet and an outlet for water, optionally a combined inlet and outlet for water, e.g. said combined inlet and outlet being provided with a self-closing valve, e.g. a slit valve or a duckbill valve,

- a reciprocable water piston member bounding said variable volume water chamber, said water piston member being reciprocable between an emptied position where the water chamber is empty and a filled position wherein the water chamber is filled with water,

- a variable volume vacuum chamber,

- a vacuum chamber piston member bounding said variable volume vacuum chamber, wherein said water piston member and said vacuum chamber member are mechanically connected and form a piston assembly,

- a user operable locking device adapted to lock and unlock said piston assembly, at least, or only, in the filled position of the water piston member, so that, in use, filling water into the variable water chamber, e.g. from a pressurized water source, e.g. provided with a pump, or from a non-pressurized water source by moving the piston assembly to the filled position, entails, e.g. causes, that said piston assembly moves with said water piston thereof into the filled position, in which process a vacuum or deeper vacuum is caused in the vacuum chamber, wherein the user operable locking device allows to lock said piston assembly as said water piston in said filled position, e.g. automatically causing said locking when in said filled position, and wherein said user operable locking device is unlockable by the user so that the vacuum acting on the vacuum chamber piston member causes the water in the water chamber to be pressurized in order of expulsion thereof from the water reservoir assembly.

In this eleventh aspect of the invention vacuum is used a power source to pressurize the water for its expulsion. The locking device allows the water to be non-pressurized, or hardly pressurized, as long as the locking device actually holds the piston assembly. As soon as the user unlocks the device, the vacuum force is transmitted via the piston assembly and causes the water to become truly pressurized. This allows for example for a design of a releasable toy water gun cartridge that has a very simple valve to keep the water in the filled cartridge, whilst the power to pressure the water being readily available within the vacuum chamber. For example a simple slit valve or duckbill valve will suffice to keep the water in the reservoir assembly.

The toy water gun water reservoir assembly can be by itself used as a toy water gun, e.g. the outlet of the water reservoir forming or being provided with the discharge nozzle thereof.

In other embodiments the toy water gun water reservoir assembly is embodied as a cartridge that is provided with a coupler for releasable coupling to a toy water gun, e.g. a single toy water gun having multiple couplers to allow simultaneous connection of multiple of such vacuum powered cartridges.

In an embodiment the reservoir assembly comprises a main housing with a first cylinder part of a first inner diameter and having at one axial end a bottom, and with a second cylinder part that adjoins the other axial end of the first cylinder part and has a second inner diameter smaller than the first inner diameter. A piston assembly is provided with a water piston member that is reciprocable in the second cylinder and is provided with a vacuum chamber piston member cylinder that is reciprocable in the first cylinder. The connection between them is formed by a piston rod, as is preferred a hollow piston rod having an inner chamber that is in open connection with the first cylinder so as to enlarge the volume of the water chamber. The vacuum chamber is then formed around the piston rod in the first cylinder. A sealing gland may be provided where the piston rod extends into the second cylinder. The bottom of the first cylinder may have one or more openings, so as to expose one side of the vacuum piston member to ambient pressure.

The locking device may be arranged at or near the bottom of the first cylinder, e.g. so as to engage of the vacuum piston member.

For example the locking device comprises a spring loaded locking member that automatically locks the piston assembly when the reservoir is full. For example the locking device comprises a push button to operate the locking member, e.g. for unlocking against a spring force.

The reservoir assembly can be permanently integrated in a toy water gun if desired, so without the option for releasing by the user. More preferred such user release is possible, e.g. for remote filling of the water reservoir assembly.

The reservoir assembly can be combined with a toy water gun into a system, e.g. with each having mating couplers, e.g. with a simple screw thread or bayonet connector between the toy water gun and the releasable reservoir assembly. One would be able to mechanically connect first, with the locking device still locked, and then later unlock the locking device to effectively cause pressurization of the water therein. If the toy water gun has a trigger a mechanism could be provided so as to connect the trigger to the locking device, so that operation of the trigger unlocks the locking device.

One can also envisage a revolver type toy water gun with multiple of these water reservoirs on a revolving structure, and with a trigger that allows the user to unlock on locking device after the other as the one water reservoir assembly is moved out of the firing position and replaced by a full water reservoir assembly.

The eleventh aspect of the invention also relates to a toy water gun water reservoir assembly according to claim 27.

In an embodiment the outlet is provided with a self-opening valve that opens under the influence of water pressure caused by release of piston assembly by actuation of the locking device. So once the locking is undone, the water is energized by the vacuum which creates water pressure which in turn opens the outlet valve. Preferably the same outlet valve is self-closing, e.g. a resilient material duck bill valve with one or more slits in a resilient duck bill membrane.

In an embodiment the outlet of the of the variable volume water chamber is provided with a duckbill valve and in series therewith and downstream thereof a fixed opening discharge nozzle. This provides for a defined plug of water being ejected as a water shot, which travels significant distance through the air. The same outlet arrangement can also be of use in other water toy guns described herein. In an embodiment the inlet is provided with a non-return valve, that opens upon user effected motion of the piston assembly to the filled position, so that water is sucked into the variable volume water chamber, e.g. from a non-pressurized water reservoir. For example the non-return valve is a resilient material duckbill valve.

The eleventh aspect of the invention also relates to a toy water gun system comprising:

- a toy water gun reservoir assembly according to claim 26 or 27, and

- a hand held toy water gun body, adapted for coupling to the toy water gun reservoir assembly, e.g. releasably coupling, or permanently integrated with the toy water gun reservoir assembly.

In an embodiment of the toy water gun system, the toy water gun body is provided with a user operable trigger mechanism including a trigger, which trigger mechanism is adapted to cooperate with said locking device of said toy water gun reservoir assembly, so that operation of the trigger by the user unlocks the locking device.

Preferably the locking device only locks the piston assembly in the filled position, so that upon a release thereof the vacuum causes the water chamber to be emptied in one go, so that a plug or shot of water emerges from the outlet of the assembly.

The eleventh aspect of the invention also relates to a water toy gun or a water toy gun reservoir assembly, e.g. a water reservoir assembly configured to be mounted on a water toy gun, comprising:

- a variable volume water chamber having an inlet and an outlet for water, optionally a combined inlet and outlet for water, e.g. said outlet or said combined inlet and outlet being provided with a self-closing valve, e.g. a slit valve or a duckbill valve,

- a reciprocable water piston member bounding said variable volume water chamber, said water piston member being reciprocable between an emptied position where the water chamber is empty and a filled position wherein the water chamber is filled with water, - a variable volume vacuum chamber coaxially with said variable volume water chamber, preferably said variable volume vacuum chamber being formed as an annular vacuum chamber extending annularly about the variable volume water chamber,

- a vacuum chamber piston member bounding said variable volume vacuum chamber, e.g. an annular vacuum chamber piston member arranged in an annular vacuum chamber extending annularly about the variable volume water chamber,

wherein said water piston member and said vacuum chamber member are mechanically connected and form a piston assembly, - preferably, a user operable locking device adapted to lock and unlock said piston assembly, at least, or only, in the filled position of the water piston member.

In operation it is envisaged that filling of water into the variable water chamber, e.g. from a pressurized water source, e.g. provided with a pump, or from a non-pressurized water source by moving the piston assembly to the filled position, e.g. the user manually moving the piston assembly, entails, e.g. causes, that said piston assembly moves with said water piston thereof into the filled position, in which process a vacuum or deeper vacuum is caused in the vacuum chamber so that the vacuum acting on the vacuum chamber piston member causes the water in the water chamber to be pressurized in order of expulsion thereof from the water reservoir assembly.

As preferred the user operable locking device allows to lock said piston assembly as said water piston in said filled position, e.g. automatically causing said locking when in said filled position, and said user operable locking device is unlockable by the user to release or unlock, so that the vacuum causes the piston assembly to move from its filled position to the emptied position, preferably such that the entire water volume chamber is emptied and said expelled water emerges as one shot of water from the assembly or the toy water gun.

It will be appreciated that in an alternative embodiment the vacuum chamber can be arranged centrally with the water chamber being annular and coaxial with the water chamber. The coaxial arrangement is structurally attractive in view of forces to be transmitted, e.g. preferred over an alternative arrangement wherein for example the vacuum chamber and the water chamber are arranged in a side by side arrangement which is, however, also encompassed within the scope of the invention. It will be appreciated by the skilled person that a feature disclosed herein primarily with reference to one aspect of the invention may be combined with another aspect of the invention, unless functionally impossible.

The present invention also relates to filling of a toy water gun reservoir as disclosed herein, playing with a toy water gun as disclosed herein, etc.

The present invention also relates to components of a toy water gun and/or cartridge as disclosed herein. The invention and various aspects thereof will now be discussed with reference to the drawings. In the drawings: Figure 1 shows a schematic drawing of toy water gun according to the first aspect of the invention,

Figure 2 shows a cross-section of an embodiment of a toy water gun according to the first aspect of the invention and a sound-producing housing according to the second aspect of the invention,

Figure 3 shows a side view of a toy water gun according to the first aspect of the invention and a sound-producing housing according to the second aspect of the invention,

Figure 4 shows a schematic illustration of the second aspect of the invention,

Figure 5 shows a schematic drawing of a sound-producing system for a toy water gun comprising a detachable first sound source and an attachment portion according to the second aspect of the invention,

Figure 6 shows a schematic drawing of a second source to be used in a sound-producing system according to the second aspect of the invention,

Figure 7 shows a schematic drawing of a toy water gun having a pulsed-mode setting according to the third aspect of the invention,

Figure 8 shows another schematic drawing of a toy water gun having a pulsed-mode setting according to third aspect of the invention,

Figure 9 shows a cross-section of a filling station that is comprised in the toy water gun system according to the fourth aspect of the invention, and

Figure 10 shows a cross-section of another embodiment of a filling station that is comprised in the toy water gun system according to the fourth aspect of the invention.

Figures 11 a-c illustrate from various angles the loading of a cartridge into the cartridge carrier of a toy water gun according to at least the fifth aspect of the invention,

Figures 12a-c illustrate the advancing of the cartridge carrier and the carrier in the toy water gun of figures 11 a-c,

Figures 13a-c, 14a -c illustrate the rotation of the advanced cartridge carrier and carrier about the connection axis,

Figures 15a-c illustrates the reverse rotation of the advanced cartridge carrier and carrier about the connection axis,

Figures 16a-c illustrate the retraction of the cartridge carrier and the carrier,

Figures 17a-c illustrate the unloading of the cartridge from the carrier,

Figures 18a-d illustrate the core member, carrier in retracted position, and cartridge loaded in the carrier, in various views,

Figures 19a-d illustrate the core member, carrier in advanced position, and cartridge loaded in the carrier, in various views,

Figures 20a-d illustrate the core member, carrier in advanced and rotated to open and locked position, and cartridge loaded in the carrier, in various views, Figure 21 shows the cartridge of figures 11-20 in filled condition with the rotary valve closed, Figure 22 shows the cartridge of figures 11 - 20 in empty condition with the rotary valve opened,

Figure 23 illustrates a toy water gun system according to the invention having multiple first connectors on the water gun,

Figures 24, 25a, b illustrate a toy water gun reservoir assembly according to the eleventh aspect of the invention,

Figures 26a, b illustrate another toy water gun water reservoir assembly according to the eleventh aspect of the invention, in cross section before and after firing a shot of water, Figures 27a, b show said toy water gun water reservoir assembly after firing the shot,

Figures 28a, b show said toy water gun water reservoir assembly of figures 26a, b integrated into a system with a hand held toy water gun body having a trigger, and

Figures 29a, b show in cross section said toy water gun system of figures 28a, b before and after firing a shot of water.

Figure 1 shows main components of a toy water gun with a water reservoir assembly 100. The water reservoir assembly 100 comprises a water reservoir 1 10, a pressurization device 120, and a connector element 130, here a rigid elongate element 130.

In the water reservoir 110 a water storage volume 11 1 is enclosed by walls 112a,b. Here the wall 1 12a is a water cylinder and the other wall 112b is a water piston acting as movable wall 112b that allows to enlarge and reduce said water volume 1 11. This movable wall 112b is movable in response to a force exerted thereon by pressurized water provided in water volume 1 10.

The pressurization device 120 has cylinder 120a and a reciprocable piston 121 that divides said cylinder into a first chamber 122 on one side of said piston 121 and a second chamber n 123 on the opposite side of said piston 121. The first chamber 122 is here embodied as a below atmospheric chamber or partial vacuum chamber, wherein some gas, e.g. air, is present at below atmospheric pressure at least in some operative positions of the piston 121. The second chamber 123 here is vented to ambient and thus filled with air at atmospheric pressure. The piston 121 is configured to prevent gas flow between said first chamber 122 and said second chamber 123 of the pressurization device. The piston 121 is movable in response to a difference in pressure between the first chamber 122 and the second chamber 123 of the pressurization device 120.

A connector structure, preferably rigid, here a rigid elongate element 130, e.g. piston rod, connects the movable wall 1 12b of the water reservoir 110 to the piston 121 of the pressurization device 120 so that a change of the water volume 11 1 results in a change of the volume of the first chamber 122. When the discharge of water from the water reservoir 110 is prevented and pressurized water is being fed into the water reservoir 110, this pressurized water exerts a force on the water piston 1 12b of the water reservoir 110 so as to enlarge the water storage volume 11 1 , which in turn enlarges the volume of the first chamber 122 of the pressurization device. Consequently the pressure in the first chamber 122 becomes lower than the pressure in the second chamber 123, or is further lowered, so that when discharge of water from the water reservoir 110 is subsequently enabled, this difference in gas pressures acting on the piston 121 between the first chamber 122 and second chamber 123 of the pressurization device 120 exerts a force on said piston 121 which is transmitted via structure 130 to the water piston 1 12b, thereby forcing water to be discharged from said water reservoir 110.

The discharge of water from the water reservoir is controlled by means of a valve 1 13, which is provided in communication with the water reservoir. This valve may e.g. be a self-closing valve, a throttle component, and/or a valve controlled by a user operated trigger.

The movable wall 112b of the water reservoir 110 may be provided with one or more seals 1 15, e.g. sealing rings, e.g. O-rings, at the interface between the movable wall 112b and other walls 112, e.g. fixed walls, of the water reservoir to ensure a good sealing at said interface.

Likewise, the piston 121 of the pressurization chamber may be provided with one or more seals 124, e.g. sealing rings, e.g. O-rings, at the interface between the piston 121 and the walls of the pressurization device cylinder 120a.

The water reservoir cylinder 112a s preferably provided with an aperture 1 16 so that the piston 112a thereof is exposed at the opposite side to ambient pressure. For example this aperture 1 16 is provided in a portion of the reservoir opposite from the water inlet and water outlet of the water reservoir 1 10.

In the present embodiment the water reservoir 1 10 and the pressurization device 120 are configured such that the cross-sectional area of the piston 121 is much larger than the cross-sectional area of the movable wall 1 12b. In an embodiment, the area of the piston 121 may be about ten times larger than that of the movable wall 112b.

In operation a partial vacuum may be provided in the first chamber 122 of the pressurization device120. The pressure in the first chamber 122 may thus be below atmospheric pressure.

In the embodiment of Figures 2 and 3 the second chamber 123 of the pressurization device 120 is in communication with ambient air through the provision of a passage 124 extending through a wall of the cylinder 120a.

Moreover, in the embodiment of Figures 2 and 3 when no water is provided to the water volume 11 1 of the water reservoir 110 the volume of said water volume 11 1 is substantially zero. Also, as preferred, in said condition the volume of the first chamber 122 of the pressurization device 120 is substantially zero.

In an embodiment, e.g. of Figures 2 and 3, the partial vacuum in the first chamber 122 of the pressurization device 120 may be such that the pressure difference between the first 122 and second chambers 123 of the pressurization device 120 is substantially independent of the operative positions of the piston 121 , so that the force provided by said pressure difference is independent of the actual position and the travel of the piston 121 in the pressurization cylinder 120a. For instance, the maximum pressure difference between the first chamber 122 and second chamber 123 of the pressurization chamber 120 may be less than 20% when comparing different positions of the piston 121 , e.g. the most inner and most outer terminal positions of the stroke of the piston during operation of the toy water gun.

In the embodiment of Figures 2 and 3 the second chamber 123 is in communication with the ambient air by means of a passage 124 extending through a wall of device 120. Herein, as preferred, the passage is provided with, e.g. a section is embodied as, an airflow controlled sound-producing device 125 adapted to provide a sound having a first frequency spectrum that is at least partially audible with the human ear when. Here in response to the reduction of the volume of the first chamber 122 of the pressurization device 120 upon enabling the discharge of water from the water reservoir 110, an air flow occurs through the passage 124 from the ambient to the second chamber 123 which airflow causes the device 125 to produce an airflow induced sound, like a whistle of similar instrument.

Moreover, the pressurization device further comprises a protrusion 126, here at the exterior side of the wall of the cylinder through which the passage 124 extends. Said protrusion 126 here is provided around the passage 124, e.g. as an addition to a sound- producing device 125 or part thereof. The protrusion is shaped to further facilitate the creation, and/or spreading of the human ear audible sound. In the present embodiment, the creation, amplification and/or spreading of said sound is facilitated by the embodiment of the protrusion 126 as a horn-shaped protrusion.

In an alternative embodiment, or complementary, a sound-producing device 125 is arranged in passage 1 16 communicating with the ambient air side of the water piston 112b.

In the embodiment of Figure 1 , with the passage 124 absent, the pressure in the second chamber 123 may be above atmospheric pressure. It is envisioned that in such an embodiment the pressure in the first chamber 122 is at or below atmospheric pressure, so that the piston 121 is moved against a higher pressure upon enlargement of the water volume 11 1. In the embodiment of Figures 2 and 3 it is seen that the expandable water reservoir is part of a toy water gun. The toy water gun further comprises a water storage container 140, here an unpressurized water container, and an inlet 141 in communication with said water container. The inlet 141 can be closed with a cap 142, e.g. for filling the container 140 from a tap or garden hose. One could also envisage a garden hose connector on the toy water gun for filling the storage contained 40.

The water container 140 is in communication with the water reservoir 1 10 of the water reservoir assembly 100 by means of a conduit 160. A pump 150 is provided in the conduit 160, with the pump inlet 151 in communication the water storage container 140 and the pump outlet 152 in communication with the water reservoir 1 10. In this way the pump, when in use, provides pressurized water to the water volume 1 11 of the water reservoir 100.

The toy water gun further comprises a trigger 161 that can be operated by a user to enable a discharge of water from the toy water gun. The trigger 161 controls the valve 113, here a ball valve, that in the open position thereof allows discharge of water and in the closed position thereof prevents discharge of water. In this embodiment the valve 113 directly precedes the outlet nozzle 162 of the toy water gun.

The toy water gun further comprises a handle 164 by which the user can hold said toy water gun while pulling the trigger 161.

The toy water gun further comprises an electrical pump drive 152, e.g. including a battery, e.g. a rechargeable battery, that is capable of powering said pump 150 and an activator 154, here in the form of a push button, that controls the powering of the pump by the battery.

Electrical wiring 157 is provided between the battery 152 and the activator 154.

Moreover electrical wiring 156 is provided between the activator 142 and the pump 150. The electrical drive 153 connects to the wiring 156 of the toy water gun through an electrical connector 155.

Figure 4 shows a schematic illustration of toy water gun 200 provided with a sound- producing system.

The toy water gun 200 has an expandable water reservoir 250 that is expandable from a relaxed state occupying a relaxation volume indicated by solid contour 250a to an expanded state occupying an additional expansion volume indicated by dash line contour 250b, and compressible from said expanded state occupying said additional expansion volume 250b back to said relaxed state occupying said relaxation volume 250a. For example, the reservoir 250 comprises a resilient material, e.g. silicone rubber, body that is expandable by internal water pressure and that is self-compressible as the stretched body tends to return to a relatively relaxed state by itself. In another embodiment the resilient material body is, e.g. externally, pressurized by one or more resilient members, e.g.

stretchable bands, around the resilient material body, or otherwise externally pressurized.

A housing 201 of the toy water gun 200 is schematically depicted. The housing 201 has an exterior and an interior. Between the housing 201 and the expandable water reservoir 250 a chamber 202 is formed, which is an air chamber of variable volume. This volume depends, as the housing is rigid, on the actual volume of the reservoir 250.

For example the housing 201 surrounds at least a part of the expandable fluid reservoir 250. The housing is provided with a passage 203 between the exterior and the interior thereof. The passage 203 is in communication with the chamber 202.

An airflow operated sound-producing element 204 is provided in or at the passage 203. The sound-producing element 204 is adapted to provide a water discharge related sound having a frequency spectrum that is at least partially audible with the human ear when in response to discharge of water from the gun 200, here including the (self-)compression of the expandable fluid reservoir 250 from the expanded state back to said relaxed state, an air flow occurs through the passage 203, here from the exterior to the interior of the housing.

The expandable fluid reservoir 250 may be an expandable water reservoir. Said expandable water reservoir is expandable in response to a pressure exerted thereon by water, e.g. pressurized water, received within said reservoir 250 and compressing from said expanded state occupying said additional expansion volume 250b back to said relaxed state occupying said relaxation volume 250a upon discharge of said water from said reservoir 250.

The expandable fluid reservoir 250 may be an expandable gas reservoir as shown in Figures 2 and 3. In these Figures the expandable gas reservoir 250 is the first chamber 122 in a pressurization cylinder that is divided by a piston 121 in a first chamber 122 on one side of said piston and a second chamber 123 on the opposite side of said piston 121. The relaxed state of the gas reservoir 250 that occupies the relaxation volume 250a corresponds to the state wherein no pressure is exerted on said piston 121 , and wherein the expanded state of the gas reservoir 250 that occupies an additional expansion volume 250b

corresponds to the state wherein a force has been exerted on said piston 121. As a result of said force the volume of the first portion 122 has expanded by an additional expansion volume 250b at the expense of the volume of the second portion 123 of the pressurization chamber 120. The first chamber 122 and second chamber 123 are filled with a gas, possibly at a pressure different from atmospheric pressure.

In the embodiment of Figure 4 the housing comprises a protrusion 205 on the exterior side thereof, wherein said protrusion 205 is provided around the passage 203 so as to extend said passage. The protrusion 205 facilitates the provision, amplification and/or spreading of said discharge sound, optionally also of a filling sound.

In the embodiment of Figure 5 the housing is provided with a detachable first sound source 206 and an attachment portion 207. The detachable sound source 206 is detachable from and attachable to said attachment portion 207. In the embodiment of Figure 6 the detachable second sound source 207 is depicted as well as a portion of the housing around the passage 203 with the sound-producing device 204 and the protrusion 205. Alternatively, as in Figures 2 and 3, the attachment portion may extend to a portion of the protrusion 205 of the housing 200.

In Figure 6 a second sound source 208 is shown. The second sound source 208 comprises a sound-producing device 210 and may comprise a connector portion 209. The second sound source 208 is detachable from and attachable to said attachment portion 207 of the housing 200. Said sound-producing device 210 is adapted to provide a discharge sound having a frequency spectrum that is at least partially audible with the human ear when in response to the compression of the expandable fluid reservoir 100 from the expanded condition back to the relaxed condition an air flow occurs through the passage 203 from the exterior to the interior of the chamber 202. The frequency spectrum of the sound-producing device 210 of the second sound source 208 is different from the frequency spectrum of the sound-producing device 204 of the first sound source 206.

Figure 7 shows a schematic drawing of a toy water gun 300 according to the third aspect of the invention.

The toy water gun 300 comprises an inlet 301 for water, e.g. pressurized water, a first water reservoir 302 in communication with said inlet 302 and a self-closing outlet nozzle 303. The self-closing outlet nozzle 303 is in communication with the first water reservoir through a main conduit 304 and opens in response to a water pressure exerted on the nozzle 303 by water in the conduit 304, thereby allowing water to be discharged through said nozzle 303.

The toy water gun 300 further comprises a pressurized second water reservoir 305 in communication with the conduit 304 and provided between the first water reservoir 302 and the self-closing outlet nozzle 303.

The toy water gun further comprises a throttle component 306 provided in said conduit 304 in between the first water reservoir 302 and the second water reservoir 305. The throttle component 306 is adapted to control by throttling, e.g. user adjustable, a flow rate of water in the conduit 304. The toy water gun 300 further comprises a trigger 307 operable by a user, e.g.

between a holding position and a discharge position.

The gun 300 further has a discharge valve 308 provided in the main conduit 304 between the second water reservoir 305 and the self-closing outlet nozzle 303. The discharge valve is adapted to be switched between a closed position to an opened position in response to an actuation of the trigger 307, e.g. from the holding position to the discharge position. In the opened position said discharge valve 308 allows water to flow to the self- closing outlet nozzle 303.

The throttle component 306 here is a throttle valve, and is here adjustable by a user and can provide a pulsed-mode setting providing a repetitive water pulses discharge mode of the toy water gun so that, with the trigger moved and kept in the discharge position and thus the discharge valve 308 in opened position, a repetitive sequence is caused wherein, if the second water reservoir 305 is filled with water at or above said opening pressure of the nozzle 303 a pulse of water is discharged from said nozzle entailing the expulsion of a portion of water from said second water reservoir 305, until said nozzle closes, and subsequently said second water reservoir is replenished with water from said first water reservoir 302 via said throttle component in said pulsed-mode throttle setting whilst said nozzle remains closed until said water in the second reservoir reaches a pressure at or above the opening pressure of the nozzle 303.

The toy water gun may further comprise pressurization means to pressurize water in said main conduit 304. Said pressurization means may be comprised in said first water reservoir 302 or associated therewith, e.g. an air pressurization arrangement using an air pump. Alternatively, as shown schematically in Figure 8, said pressurization means may include a water pump 309 provided in the conduit 304 between the first water reservoir and the throttle component 306.

The first water reservoir 302 may be embodied as a first expandable water reservoir that is expandable e.g. in response to a pressure exerted thereon by pressurized water received in said reservoir 302. Said first water reservoir 302 may for instance be embodied as an expandable bladder, e.g. comprising a body of an elastomeric material.

The pressurized second water reservoir 305 may be an expandable second water reservoir 305 that is expandable in response to a pressure exerted thereon by pressurized water received in said second reservoir 305. Said second water reservoir may for instance be embodied as an expandable bladder, e.g. comprising a body of an elastomeric material. The pressurized second water reservoir 305 may be embodied as a water reservoir in a water reservoir assembly according to the first aspect of the invention. Thus, the second water reservoir 305 may comprise a water reservoir, a pressurization device, and a connector structure as described according to the first aspect of the invention. In such an embodiment, the discharge of water from the second water reservoir 305 is prevented and enabled by the self-closing outlet nozzle 303.

In the embodiment of the toy water gun of Figures 7 and 8 the communication of the second water reservoir 305 with the conduit 304 is provided by a single connector conduit 310 that serves both as an inlet and as an outlet to the second water reservoir 305.

In the pulsed-mode setting of the throttle component 306 the self-closing outlet nozzle 303 may be adapted to close after a discharge of a pulse of water only when the second water reservoir 305 has become substantially empty of water, e.g. when at least 80% of the water that was in the second water reservoir 305 has been discharged. Thus the effective volume of said reservoir 305 then approximates the volume of a single pulse of water.

Moreover, in the pulsed-mode setting of the throttle component 306 the self-closing outlet nozzle 303 may only open when the second water reservoir 305 is fully filled with water and the second water reservoir 305 has expanded in response to the pressure exerted thereon by the water received in the second water reservoir 305.

The throttle component 306 of the toy water gun 300 may be embodied to also provide a continuous-mode setting wherein, when the first water reservoir 302 has been filled with a water and the discharge control 307 is moved to and kept in the discharge position, the pressure of water in the conduit is such that the self-closing outlet nozzle 303 is in response to the pressure exerted thereon by the water from said first water reservoir 302 continuously open, so as to create a continuous discharge of water through said self-closing outlet nozzle 303. Thus, according to this embodiment water is discharged through the self- closing outlet nozzle both in the pulsed-mode setting and in the continuous-mode setting.

The self-closing outlet nozzle 303 may be embodied as a unitary self-closing outlet nozzle, for instance provided with a slit valve.

Figure 9 shows a filling station 400 of a toy water gun system according to the fourth aspect of the invention.

The toy water gun system according to the fourth aspect of the invention comprises a filling station and a toy water gun, e.g. a toy water gun as shown in Figure 2, 3, 7 or 8.

The toy water gun comprises an expandable water reservoir that is expandable in response to a pressure exerted thereon by pressurized water received in said reservoir, a water inlet to provide pressurized water to said expandable water reservoir, an outlet nozzle in communication with said expandable water reservoir and a discharge control movable by a user between a holding position and a discharge position, wherein the discharge control in the discharge position allows water to be discharged from said expandable water reservoir via said nozzle.

The filling station 400 comprises a water inlet 401 and a water pump 402 to pressurize the water, wherein the inlet 403 of the pump 402 is in communication with the water inlet 401. The filling station moreover comprises an electrical drive 405 to electrically drive the pump 402 and a water outlet 406 to discharge water that has been pressurized by said pump 402, wherein the water outlet 406 is in communication with the outlet 404 of the pump 402.

The water inlet of the toy water gun is attachable to the water outlet 406 of the filling station so as to allow communication between said water outlet 406 and water inlet. The water inlet of the toy water gun is detachable from said water outlet 406.

The filling station 400 may further comprise a water tank 407 adapted to store therein unpressurized water as shown in Figure 10. The water tank 407 in Figure 10 is provided in between the water inlet 401 and the inlet of the pump 403 and is in communication with the water inlet 401 and the pump 402. The water tank 407 is provided with a cap 414 covering the inlet 401 of the filling station.

The water inlet 401 of the toy water gun may in the embodiment of the filling station of Figure 9 be attachable to a water hose. Also in the embodiment of Figure 10 the water inlet may be connectable to a water hose. In the embodiment of Figure 10 water may also be provided to the filling station 400 without a water hose, e.g. by placing the water inlet 401 of the filling station 400 under a tap, e.g. by using a funnel provided to the inlet and a bucket with water.

In the embodiments of Figure 9 and 10 the electrical drive 405 comprises a battery, preferably a rechargeable battery.

In the embodiments of Figures 9 and 10 the filling station comprises a housing 408. The water reservoir 407 and pump 402 are provided substantially within the housing. The water outlet 406 of the filling station 400 extends at least partially from the housing 408.

In the embodiments of Figure 9 and 10 the water outlet 406 of the filling station comprises a connector tube 409, e.g. a flexible connector tube, that extends from the housing. The connector tube 409 has a pump end 409a in communication with the pump 402, more in particular in communication with the outlet 404 of the pump 402. The connector tube 409 has a water gun end 409b to which the toy water gun can be attached.

In the embodiments of Figure 9 and 10 the filling station 400 comprises an activator 410. When the toy water gun has been attached to the water outlet 406 of the filling station 400 the pump 402 upon operation of the activator 410 pressures water that is provided to the filling station 400.

In the embodiments of Figure 9 and 10 the filling station 400 is portable, e.g. by means of carrying grips 411 provided to the housing 408 of the filling station 400.

In the embodiment of Figure 10 the tank 407 of the filling station 400 is portable, e.g. by means of the carrying grips 410. The tank is attachable and detachable from other components, e.g. the pump 402, electrical drive 405, actuator 410 and water outlet 406, of the filling station.

The volume of the water tank 407 of the filling station 400 may be multiple times the volume of the expandable water reservoir of the toy water gun, e.g. ten times the volume of the expandable water reservoir, e.g. five times the volume of the expandable water reservoir, e.g. three times the volume of the expandable water reservoir.

The toy water gun of the toy water gun system may comprise an expandable water reservoir comprising a water reservoir, a pressurization chamber and a rigid elongate element according to the first aspect of the invention.

In addition, the toy water gun of the toy water gun system may comprise a sound- producing design according to the second aspect of the invention. The toy water gun system may for instance comprise the filling station of Figure 9 and

10 and the toy water gun of Figures 2 and 3 with expandable water reservoir 100 and/or sound-producing housing 200.

With reference to figures 11 - 22 a toy water gun system according to at least the fifth aspect of the invention will be explained.

Generally the toy water gun system comprises a hand held toy water gun 500 and one or more, preferably multiple, cartridges 600. In this embodiment the water gun 500 is designed to be loaded with a single cartridge at a time.

As will be explained below, and as is preferred, the cartridge 600 is a pre-pressurized type cartridge which - when filled - stores a volume of water in its reservoir at an above atmospheric pressure. For example in an embodiment and when filled directly from a water mains, said pressure approximates the water mains pressures.

Generally, whilst not shown here, the water gun 500 comprises a water circuit comprising:

- a water discharge outlet, 501

- a discharge control, here a discharge valve operated by a trigger 502. This allows a user to control the discharge from water discharge outlet,

- a first connector 503, here a male connector, having an inlet of said water circuit. The cartridge 600 has a cartridge housing 601 , e.g. of robust plastic material, e.g. impact resistant plastic material.

Within said housing 601 a water reservoir 605 is arranged that is adapted to store a water volume therein.

Here the reservoir 605 is a pre-pressurizable water reservoir that is adapted to store water therein under pressure. In more detail the reservoir 605 has a body of resilient or elastic stretchable material, e.g. of silicone rubber, that is expanded (see figure 21) upon feeding pressurized water into said expandable body and that is self-compressing so as to return to a relaxed condition(see figure 22). As is preferred the housing 601 delimits the most expanded state of the reservoir 605.

The reservoir 605 has a single opening, the perimeter thereof being secured to the housing 601 , e.g. as here by being clamped between a clamping collar part 602 of the housing and a beaker shaped part 603 of the housing.

The cartridge 600 is provided with a second connector 620, here a female connector. In more detail the second connector 620 comprises a tubular, open ended portion 604, of the collar part 603. This portion 604 is provided with one or more water ports 606. The portion 604 extends into the reservoir 605. The bore 608 of the female connector is thus formed by this tubular portion 604 that stationary secured to the housing 601 of the cartridge 600.

A rotary valve member 610 is journalled externally about the tubular portion 604. The member 610 has one or more ports 611 , here just as the portion 604 one or more radial ports. In a first angular position these ports 606, 61 1 are out of alignment such that said rotary valve is closed (see figure 21) and in a second angular position these ports 606, 61 1 are aligned so that said rotary valve of the cartridge 600 is open.

The cartridge 600 is releasably connectable to the toy water gun 500 and the first and second connectors 503, 620 are connectable to one another so as to establish a connection between the water port of the water reservoir 605 of the cartridge 600 and the inlet of the water circuit of the handheld to water gun 500.

As will be appreciated the first and second connectors are adapted to be connected to one another by advancing the cartridge 600 along a connection axis relative to the toy water gun 500 into an advanced position of the cartridge 600 and to be disconnected from one another to be retracting the cartridge along said connection axis.

The toy water gun 500 comprises a core member 510 aligned with the connector axis and provided at one end thereof with the male first connector 503.

A water duct 505 extends through the core member 510 and the connector 503 to the inlet 504 formed by one or more radial ports in the connector 503.

As can be seen in figures 18 - 20 the male first connector 503 is provided with a first valve assembly which is adapted to close the inlet 504 of the water circuit in case the cartridge 600 is disconnected from the toy water gun 500, and to open the inlet of said water circuit in case said cartridge is connected to said toy water gun 500.

In more detail the first valve assembly comprises a rotary valve member 512 that is arranged around the male first connector 503 and that is rotatable relative to said connector between first and second angular positions. The tubular rotary valve member 512 comprises one or more ports 513, here radial, therein which in said first angular position non-aligned with the one or more ports 504 and in said second position are aligned so that the first valve assembly is open.

As will be explained later, it is envisaged that the first rotary valve member 512 couples to the housing 601 of the advanced cartridge so as to be held in same position as said cartridge housing and thus to be rotated about the connection axis along with the rotation of the cartridge housing itself.

The toy water gun further comprises a cartridge carrier 530 adapted to receive the cartridge 600. The carrier 530 is translatable in the toy water gun. In more detail the combination of the carrier 530 and the loaded cartridge 600 is manually translatable along the connection axis. The carrier 530 is adapted to receive the cartridge 600 therein in a retracted position of the carrier.

In the depicted embodiment the carrier 530 has a receiving cradle 535 into which a portion of the cartridge is laterally insertable, perpendicular to said connection axis. Once inserted laterally the cradle 535 retains the cartridge 600 axially, so in direction of said connection axis.

The carrier 530 further comprises an annular portion 540 that is mounted over the core member 510 and translatable along said core member 510. The carrier 530 is also rotatable about the core member 510 between first and second angular positions, corresponding to first and second angular positions of the first and second valves of the system. The cartridge carrier 530 is provided with a bolt handle 550 for manual engagement by a user.

The toy water gun has an external housing 560 that is provided with an L-shaped bolt handle slot 565, with a longitudinal portion 565a through which said bolt handle 550 is slided by the user for advancing and retracting the carrier 530 along the connection axis, and a transverse portion 565b at an advanced position end of said longitudinal portion through which said bolt handle 550 is slided by a user for rotating the carrier about said connection axis.

The depicted toy water gun also comprises a bayonet structure that locks the carrier 530, and thus the retained cartridge 600, in axial direction, here in addition to the bayonet structure of the bolt handle and the associated slot in the external housing. Alternatively said bayonet between the carrier and the core member can replace the bolt handle and slot type bayonet.

Here the core member is provided with an L-shaped bayonet groove 515 and the carrier 530 is provided with a mating boss 516. The groove 515 has a longitudinal portion 515a parallel to the connection axis and a locking portion 515b at an end of said longitudinal portion and transverse to said longitudinal portion. This bayonet structure is arranged such that, upon advancing the cartridge 600 by means of the carrier 500 to the advanced position thereof, the boss 516 slides through said longitudinal portion thereby preventing a manually caused rotation of the rotary valve member of the cartridge 600 from the first angular position into the second angular position, and such that, upon having reached the advanced position of the cartridge and the user manually causing rotation of the rotary valve member from said first angular position into said second angular position, the boss 516 slides through the locking portion of the bayonet groove 515 thereby opening the second valve assembly and preventing a retraction of the cartridge along said connection axis.

Due to the coupling of the rotary valve member of the first valve to the cartridge housing in the advance position, the rotation of the carrier 530 also causes the first valve assembly to be opened. So now pressurized water stored in the pre-pressurized cartridge 600 can flow into the water circuit of the toy water gun and, e.g. expelled upon actuation of the trigger thereof.

For effecting the opening of the second valve it is envisaged the first connector 503 is, here at the front end thereof, provided with a first coupling member 517, here a protrusion. The rotary valve member comprises a second coupling portion, here a cavity 618 into which the protrusion is received and a torsional connection is obtained. This second coupling portion is such that, when the rotary valve member is in said first angular position, it is adapted to couple to the first coupling portion upon said axial advancing of the cartridge along a connection axis relative to the toy water gun into said advanced position. As the rotary member is now as it were stationary retained, a subsequent rotation of the carrier 530 and the cartridge 600 causes the second valve to open.

It is also depicted that the toy water gun is provided with a water feed connector 570, here a hose coupler for a garden hose, which connecter is connected to said water circuit, e.g. via a check valve. This allows to fill an empty cartridge 600 when connected to the toy water gun 500.

Figure 23 depicts a toy water gun system comprising a toy water gun 700 and comprising a water circuit comprising:

- a water discharge outlet 701 ,

- a discharge control 702 operable by a user allowing water to be controllably discharged from said water reservoir via said water discharge outlet,

- multiple first connectors 703, here male connectors, each having an inlet of said water circuit.

The water gun can be loaded with multiple cartridges 600, here three, each having a cartridge housing and being provided with a water reservoir adapted to store a water volume therein, said cartridge further being provided with a second connector having a water port of said water reservoir.

Here, each cartridge is releasably connectable to the toy water gun 700 and the first and second connectors are connectable in pairs to one another so as to establish a connection between the water port of the water reservoir of the cartridge and the inlet of the water circuit of the toy water gun.

As can be seen each first connector 703 is provided with a first valve assembly, here with a sliding tubular valve member 704 that is urged by a spring 705 into a closed position wherein the member 704 closes a radial port in the connector 703. As can be seen upon connecting a cartridge 600 to the respective connector 703 the valve 704 is pressed down to open the first valve assembly. When removing a cartridge 600 the valve 704 automatically closes, thereby keeping the circuit closed so that the one or more other loaded cartridges remain operational.

Generally as described with reference to figures 1 1 - 22 the cartridges 600 are each provided with a rotary valve assembly and with a second connector.

The first and second connectors are adapted to be connected to one another by advancing the cartridge 600 along a connection axis relative to the toy water gun into an advanced position of the cartridge and to be disconnected from one another to be retracting the cartridge along said connection axis. In this embodiment the toy gun has no cartridge carrier and the cartridges are directly manually placed on the toy gun with the connectors being interconnected.

The second connector comprises a base mounted to the cartridge housing and a rotary valve member journaled to the base.

The eleventh aspect of the invention relates to a toy water gun water reservoir assembly and will be discussed with reference to the version in figures 24, 25a, b and the version in figures 26 - 29.

The toy water gun water reservoir assembly 900 comprises:

- a variable volume water chamber 901 having an inlet and an outlet for water, here a combined inlet and outlet 902 for water, e.g. said combined inlet and outlet being provided with a self-closing valve, e.g. a slit valve (not shown),

- a reciprocable water piston member 903 bounding said variable volume water chamber 902, said water piston member being reciprocable between an emptied position where the water chamber is empty (not shown) and a filled position wherein the water chamber is filled with water (shown),

- a variable volume vacuum chamber 905,

- a vacuum chamber piston member 906 bounding said variable volume vacuum chamber, wherein said water piston member 903 and said vacuum chamber piston member 906 are mechanically connected and form a piston assembly 910,

a user operable locking device 920 adapted to lock and unlock said piston assembly 910, at least in the filled position of the water piston member, so that, in use, filling water into the variable water chamber causes said piston assembly 910 to move with said water piston thereof into the filled position, in which process a vacuum or deeper vacuum is caused in the vacuum chamber 905, wherein the user operable locking device 920 allows to lock said piston assembly as said water piston member 903 is in said filled position, e.g. automatically causing said locking when in said filled position, and wherein said user operable locking device 920 is unlockable by the user so that the vacuum acting on the vacuum chamber piston member 906 causes the water in the water chamber to be pressurized in order of expulsion thereof from the water reservoir assembly.

In this aspect of the invention vacuum is used a power source, preferably the sole power source, to pressurize the water for its expulsion. The locking device 920 allows the water to be non-pressurized, or hardly pressurized, as long as the locking device 920 actually holds the piston assembly 910. As soon as the user unlocks the device 920, the vacuum force is transmitted via the piston assembly 910 and causes the water to become truly pressurized. This allows for example for a design of a releasable toy water gun cartridge that has a very simple valve to keep the water in the filled cartridge, whilst the power to pressure the water being readily available within the vacuum chamber. For example a simple slit valve will suffice to keep the water in the reservoir assembly.

The toy water gun water reservoir assembly can be by itself used as a toy water gun, e.g. the outlet 902 of the water reservoir assembly forming the discharge nozzle thereof.

In other embodiments, as shown here, the toy water gun water reservoir assembly is embodied as a cartridge that is provided with a coupler for releasable coupling to a toy water gun, e.g. a single toy water gun having multiple couplers to allow simultaneous connection of multiple of such vacuum powered cartridges.

In an embodiment the reservoir assembly comprises a main housing 930 with a first cylinder part 931 of a first inner diameter and having at one axial end a bottom 932, and with a second cylinder part 933 that adjoins the other axial end of the first cylinder part and has a second inner diameter smaller than the first inner diameter. A piston assembly 910 is provided with a water piston member 903 that is reciprocable in the second cylinder part 933 and is provided with a vacuum chamber piston member 906 that is reciprocable in the first cylinder part 931. The connection between them is formed by a piston rod 935, as is preferred a hollow piston rod 935 having an inner chamber 936 that is in open connection with the second cylinder 933 so as to enlarge the volume of the water chamber 901. The vacuum chamber 905 is then formed around the piston rod 935 in the first cylinder part 931.

A sealing gland 937 is provided where the piston rod 935 extends into the second cylinder part 933. The bottom of the first cylinder has one or more openings 938, so as to expose one side of the vacuum piston member 906 to ambient pressure.

If desired a reset vent 941 with a valve 942 therein may be provided for the vacuum chamber allowing a user to restore vacuum in the chamber 905 in case air has managed to get inside, e.g. along a seal of piston 906.

The locking device 920 is arranged at or near the bottom of the first cylinder part 931 , here so as to engage of the vacuum piston member 906.

For example the locking device 920 comprises a spring 922 loaded locking member 921 that automatically locks the piston assembly when the reservoir is full. For example the locking device comprises a push button 923 to operate the locking member, e.g. for unlocking against a spring force.

One can also envisage a revolver type toy water gun with multiple of these water reservoirs on a revolving structure, and with a trigger that allows the user to unlock on locking device after the other as the one water reservoir assembly is moved out of the firing position and replaced by a full water reservoir assembly. With reference to figures 26a, b and 27 a, b another toy water gun water reservoir assembly 1000 according to the eleventh aspect of the invention will be discussed here. It will be appreciate that this design has many details in common with the toy gun described with reference to the figures 24, 25a, b.

As will be explained it is envisaged that this assembly 1000 can be integrated with a hand held toy water gun body having a trigger, e.g. as shown in figures 28a, b and 29a, b.

The toy water gun water reservoir assembly 1000 comprises a variable volume water chamber 1001 within a tubular body 1002 of a housing of the assembly. The housing forms at one end of the tubular body both an inlet 1003 and an outlet 1004 for water.

A reciprocable water piston member 1005 is slidable in the tubular body 1002 and bounds the variable volume water chamber 1001 , here at the end thereof opposite the inlet 1003 and outlet 1004.

The water piston member 1005 is reciprocable between an emptied position, see figure 26b, where the chamber 1001 is empty, that is has its minimum volume, and a filled position, see figure 26a, wherein the chamber 1001 is filled with water, that is has its maximum volume.

The housing of the assembly 1000 also delimits a variable volume vacuum chamber 1010, here concentric about the tubular body 1002 that delimits the variable volume water chamber 1001. As shown the housing here has an inner tubular body 1002 and concentric therewith an outer tubular body 1011 to form between them an annular variable volume chamber 1010.

The assembly 1000 further comprises a vacuum chamber piston member 1015 that bounds the variable volume vacuum chamber 1010. Here the vacuum piston member 1015 is annular to sealing slide between the inner and outer tubular bodies 1002 and 1011.

The water piston member 1005 and the vacuum chamber piston member 1015 are mechanically connected to one another and form a piston assembly 1020 of the assembly 1000. The assembly 100 further has a user operable locking device 1030 that is configured to lock and unlock this piston assembly 1020, at least in the filled position of the water piston member 1005, see figure 26a.

It will be appreciated that displacement of the water piston member 1005 from the emptied position to the filled position in the course of filling water into the variable water chamber 1001 causes a vacuum or a deeper vacuum in the variable volume vacuum chamber 1010 as the piston members 1005 and 1015 are mechanically connected, here integrated into one piston assembly 1020. The user operable locking device 1030 is configured to lock the entire piston assembly 1020 in the filled position of the water piston member 1005. As preferred this locking is done automatically so as to cause the locking when the filled position is reached,.

The user operable locking device 1030 is unlockable by the user so that the vacuum in the variable volume vacuum chamber 1010 acts on the vacuum chamber piston member 1015 and thereby on the piston assembly 1020 which causes the water piston member 1005 to pressurize the water in the water chamber 1001 and expel said pressurized water as a shot via the outlet 1004 of the variable volume water chamber 1001.

It will be appreciated that there is no need for a mechanic spring to energize the water piston member 1005, and preferably the member 1005 is solely energized by the vacuum.

The discharge of the shot of water here is done via a slit valve 1040 held in the housing of the assembly 1000, and downstream and in series therewith a nozzle 1045 with a fixed discharge opening. The slit valve 1040 is self-closing.

The inlet of water into the chamber 1001 is governed here by a check valve, here a further slit valve 1050, that opens once the piston assembly 1020 is pulled back by a user manually.

The piston assembly 1020 is provided with a user grip 1025, here at the axial end thereof that protrudes from the housing of the assembly 1000, so that the user can take hold of this grip 1025 and move the assembly 1020 so as to fill the chamber 1001 with water and at the same time create a vacuum or deeper vacuum in the chamber 1010.

In the embodiment shown the locking device 1030 comprises a mobile lock member 1031 that engages a locking groove 1032 on the piston assembly 1020 in the filled state of the water chamber 1001. The mobile locking member 1031 here is operable at right angles to the piston assembly motion axis. Here a biasing spring 1033 urges the locking member 1031 into its locked position, and a force on the locking member 1031 counter to the spring action causes the release of the lock and thereby the vacuum will cause the piston assembly to move and expel pressurized water from the assembly 1000. Vacuum in the chamber 1010 can be restored or influenced by means of a user operable valve, here umbrella valve 1017 between the atmosphere and the vacuum chamber 1010.

Figures 26a, b and 27a, b show that inlet of the assembly may be connected via a hose part 1055 to some water supply, e.g. to a non-pressurized water storage reservoir.

Figures 28a, b and 29a, b illustrate that the assembly 1000 can be integrated with a hand held toy water gun body 1 100 having a trigger 1 102 that serves to operate the locking device 1030 of the assembly 1000.

Here the gun body 1 100 comprises a non-pressurized water storage tank 1 105 that connects via hose part 1050 to the assembly 1000.

In this example the assembly 1000 is permanently integrated with the body 1 100. In another embodiment the assembly 1000 is releasably mounted on the body 1 100, e.g.

allowing to use the same assembly 1000 with different design bodies 1 100 or the other way around.

The body 1 100 has a hand grip, here a pistol grip 11 10. The body further comprises a user operable trigger 11 15 that is operatively connected to the locking device 1030 of the assembly 1000.

Here the trigger 1 1 15 is based into a initial position by spring 1 120, so that the user pulls the trigger 1 115 against the spring 11 15 to fire a shot of water from the assembly 1000 as this operation unlocks the locking device 1030.

In this example the trigger 1 115 displaces locking member 1031 from its locked position into its unlocked or release position. Once unlocked the vacuum moves the piston assembly 1020 all the way until the chamber 1001 is emptied as the locking device only locks in the filled position.

Here the trigger 1 115 has a cam face of ramp 11 17 that cooperates with member 1031 to move the locking device 1030 from its locked into its unlocked state.

Once the shot of water starts, the piston assembly will travel all the way to the emptied position.

For refilling the user pulls the piston assembly 1020 to the filled position, which causes water to be sucked from non-pressurized tank 1 105 into the chamber 1001. Upon reaching the filled position the locking member 1031 snaps into its locked position, here spring 1033 urging the member 1031 into groove 1032 on the piston assembly 1020. Now the water toy gun system is ready to fire another shot of water.

The vacuum energizing of the water in the assembly 1000 is very powerful and the shot of water travels far. In an embodiment the gun body is provided with or is adapted to receive multiple assemblies 1000 simultaneously, e.g. allowing a user to fire multiple shots simultaneously and/or shortly after one another. For example the trigger is adapted to release the one locking device shortly after the release of the other locking device, so that the shots are fired closely after one another. In an alternative the user can choose between firing single shots by each time operating the trigger, and having a single actuation of the trigger firing multiple shots from as many assemblies 1000.

Claims

C L A I M S

1. A toy water gun comprising:

- a water discharge outlet (162),

- a discharge valve (1 13) controlling discharge of water from said water discharge outlet, e.g. a trigger controlled discharge valve (1 13),

- a water reservoir assembly comprising:

- a water reservoir (1 10) having an inlet (1 10a) and an outlet (1 10b), said water reservoir comprising walls (1 12a, 112b) enclosing a variable water volume (11 1) in said water reservoir, wherein at least one of said walls is a movable wall (1 12b) allowing variation of said water volume, wherein said movable wall (1 12b) is movable in response to a force exerted thereon by pressurized water fed into said variable water volume via said inlet (1 10a),

- a pressurization device (120) comprising a pressurization cylinder (120a), wherein a piston (121) is reciprocable in said cylinder (120a) and defines in said cylinder a first chamber (122) on one side of said piston and a second chamber (123) on the opposite side of said piston, wherein said first and second chambers (122,123) are filled with a gas, e.g. air, wherein said piston is movable in response to a difference in gas pressure between the first chamber and second chamber, and

- a connector structure (130), e.g. a rigid elongate connector element, e.g. a piston rod, that connects the movable wall (1 12b) of the water reservoir to the piston (121) of the pressurization device (120) so that a change of the water volume results in a change of the volume of each of the chambers,

wherein said pressurization device is embodied such that, when discharge of water from said water reservoir is prevented by said discharge valve (1 13) and pressurized water is being fed into said water reservoir via the inlet (1 10a) of the water reservoir, said pressurized water exerts a force on said movable wall (1 12b) of the water reservoir so as to enlarge said water volume, which in turn causes enlargement of the volume of the first chamber (122) of said pressurization device and reduction of the volume of the second chamber of said

pressurization device thereby the gas pressure in the first chamber (122) becoming lower than the gas pressure in the second chamber (123) thus exerting a force on said piston (121) so as to reduce the volume of the first chamber which is transmitted via said connector structure (130) to said movable wall (1 12b) so as to pressurize said water in said water reservoir,

such that when discharge of water from said water reservoir is subsequently enabled by said discharge valve (1 13), said pressurization device (120) pressurizes said water that is discharged from said water reservoir.

2. A toy water gun according to claim 1 , wherein the cross-sectional area of the piston (121) of said pressurization device is larger than the cross-sectional area of the movable wall (1 12b), e.g. two or more times larger, e.g. four or more times larger.

3. A toy water gun according to claim 1 or 2, wherein the pressurization device (120) is embodied such that a partial vacuum is present and/or caused in the first chamber (122) of said pressurization device upon feeding pressurized water into the water reservoir (1 10).

4. A toy water gun according to one or more of the preceding claims 1 - 3, wherein the pressurization device (120) comprises a passage (124) that vents the second chamber (123) of the pressurization device to the ambient air.

5. A toy water gun according to at least claim 3, wherein the pressurization device (120) is embodied such that when no or a minimum water volume is present in the water reservoir the volume of the first chamber (122) is substantially zero so that a partial vacuum is caused in the first chamber of said pressurization device upon feeding pressurized water into the water reservoir.

6. A toy water gun according to claims 3, 4 and 5,wherein the pressurization device (120) is embodied such that the partial vacuum in the first chamber (122) is substantially independent of the position of the piston (121), so that the force provided by said pressure difference is substantially independent of positions of the piston between completely filled and completely emptied water reservoir states, e.g. said partial vacuum differing at most 20% between said different positions of the piston.

7. A toy water gun according to at least claim 4, wherein the second chamber (123) is in communication with the ambient air by means of the passage (124) extending through a wall of said cylinder, wherein said passage is provided with an airflow operated sound-producing device (125) being adapted to provide a sound having a first frequency spectrum that is at least partially audible with the human ear when, in response to the reduction of the volume of the first chamber (122) upon enabling the discharge of water from the toy water gun, an air flow occurs through said sound-producing device (125) from the ambient to the second chamber (123).

8. A toy water gun according to claim 7, wherein said pressurization device further comprises a protrusion (126) at an exterior side of the wall of the cylinder through which said passage (124) extends, which protrusion is shaped to further facilitate the creation and/or spreading of said sound, e.g. a horn-shaped protrusion.

9. A toy water gun according to one or more of the preceding claims, wherein the water reservoir has a water reservoir cylinder (1 12a) forming a wall of said water reservoir, and a water piston (1 12b) that is reciprocable within said water reservoir cylinder and forms said movable wall of said water reservoir, e.g. said piston of the pressurization device and said water piston being aligned on a common axis and, e.g. being directly connected to one another via a rigid elongated piston rod (130).

10. A toy water gun according to one or more of the preceding claims, further comprising:

- a water storage container (140), preferably an ambient pressure water storage reservoir, e.g. adapted to store, e.g. at ambient pressure, a volume of water significantly greater than said water reservoir volume (1 11), e.g. at least 10 times greater than said water reservoir volume, e.g. said water storage container being permanently integrated with said toy water gun or releasably mounted to the toy water gun, e.g. said water storage container preferably having fill opening (141) for filling said water storage container with water, e.g. from a tap, and

- a water pump (150) integrated with said toy water gun, e.g. an electric motor driven water pump (150), said water pump having a pump inlet (151) and a pump outlet (152), wherein the inlet of said water pump is in communication with said water storage container (140), and wherein the pump outlet (152) of said water pump is in communication with the inlet (1 10a, b) of the water reservoir, so as to be able to provide pressurized water to said water reservoir.

1 1. A toy water gun according to one or more of the preceding claims, wherein the inlet (1 10a) and the outlet (110b) of the water reservoir are combined in a combined inlet and outlet (1 10a, b), and wherein a water duct (116) extends between the combined inlet and outlet (1 10a, b) of the water reservoir on the one hand and said water discharge valve (1 13) on the other hand, e.g. in an embodiment according to claim 10 wherein said pump outlet (152) is connected to said water duct (116).

12. A toy water gun according to one or more of the preceding claims, wherein said cylinder (120a) of said pressurization device (120) is at least partially transparent so as to allow a user of the toy gun to see the piston therein.

13. A method to store pressurized water in a toy water gun, said method making use of toy water gun with a water reservoir assembly according to one or more of the preceding claims 1 - 12.

14. A water reservoir assembly configured for use in a toy water gun according to one or more of the preceding claims 1 - 12.

15. A toy water gun comprising:

- a water discharge outlet (162),

- a discharge valve (113) controlling discharge of water from said water discharge outlet, e.g. a trigger controlled discharge valve (1 13),

- a variable volume chamber (123;202) that has a volume and that is in communication with the ambient air via a passage (124;203), wherein said volume of said variable volume chamber is dependent on discharge of water from said water discharge outlet such that upon discharge of water air passes through said passage into or out of said variable volume chamber,

wherein said passage (124;203) is provided with an airflow operated sound-producing device (125;204) being adapted to provide a water discharge related sound having a first frequency spectrum that is at least partially audible with the human ear when, in response to the discharge of water from the toy water gun, an air flow occurs through said sound-producing device (125).

16. A sound-producing system for use with a toy water gun, wherein a variable volume chamber is delimited in the water toy gun, said system comprising:

- a first sound source comprising a first airflow operated sound-producing device attached or to be attached to the toy water gun, wherein said first sound source may be detachable from and attachable to a common attachment portion of the toy water gun, wherein said first airflow operated sound-producing device is adapted to provide a water discharge and/or filling related sound having a first frequency spectrum that is at least partially audible with the human ear when, in response to the discharge of water from the toy water gun and/or filling water into a water reservoir of the toy water gun, an air flow occurs through said first sound- producing device,

- a second sound source comprising a second airflow operated sound-producing device attached or to be attached to the toy water gun, wherein said second sound source may be detachable from and attachable to said common attachment portion of the toy water gun, wherein the second airflow operated sound-producing device is adapted to provide a discharge sound and/or a filling sound having a frequency spectrum that is at least partially audible with the human ear when in response to water discharge from the water toy gun and/or filling of a water reservoir of the water toy gun an air flow occurs through said second sound-producing device ,

wherein the frequency spectrum of the second airflow operated sound-producing device is different from the frequency spectrum of the first airflow operated sound-producing device.

17. A toy water gun comprising:

- an inlet (301) for water, e.g. for pressurized water,

- a first water reservoir (302) in communication with said inlet,

- a self-closing outlet nozzle (303), said self-closing outlet nozzle in communication with the first water reservoir through a conduit (304), wherein said self-closing outlet nozzle opens in response to an opening pressure exerted on said nozzle by a water in said conduit (304), thereby allowing said water to be discharged from the toy water gun through said nozzle (303),

- a pressurized second water reservoir (305) in communication with the conduit (304) and provided between the first water reservoir (302) and the self-closing outlet nozzle (303),

- a throttle component, e.g. a throttle valve (306) provided in said conduit (304) in between the first and the second water reservoirs (302,305), said throttle component adapted to control a flow rate of water in the conduit (304),

- a trigger (307) operable by a user and having a holding position and a discharge position, and

- a discharge valve (308) provided in the conduit (304) between the second water reservoir (305) and the self-closing outlet nozzle (303), said discharge valve being switchable between a closed position and an opened position by operation of the trigger, said discharge valve in the opened position allowing water to flow to the self-closing outlet nozzle (303),

wherein the throttle component (306) provides a pulsed-mode throttle setting providing a repetitive water pulses discharge mode of the toy water gun so that, with the trigger moved and kept in the discharge position and thus the discharge valve (308) in opened position, a repetitive sequence is caused wherein, if the second water reservoir (305) is filled with water at or above said opening pressure of the nozzle (303), a pulse of water is discharged from said nozzle entailing the expulsion of a portion of water from said second water reservoir (305), until said nozzle closes, and subsequently said second water reservoir is replenished with water from said first water reservoir (302) via said throttle component in said pulsed- mode throttle setting whilst said nozzle remains closed until said water in the second reservoir reaches a pressure at or above the opening pressure of the nozzle (303).

18. Toy water gun according to claim 17, wherein the throttle component also provides a continuous-mode setting so that, with the trigger moved and kept in the discharge position and thus the discharge valve (308) in opened position, said nozzle is opened by water in said conduit (304) having a pressure at or above said opening pressure of the nozzle (303), said discharge causing a flow from said first water reservoir through said throttle component (306) in said continuous-mode setting with a flow rate and pressure downstream of said throttle component such that said nozzle remains open so as to create a continuous discharge of water through said self-closing outlet nozzle as long as said trigger is kept in said discharge position.

19. Toy water gun system comprising:

- a toy water gun, said toy water gun comprising:

- an expandable water reservoir (1 10) that is expandable in response to a pressure exerted thereon by pressurized water received in said reservoir,

- a water inlet to provide pressurized water to said expandable water reservoir,

- an outlet nozzle in communication with said expandable water reservoir, and

- a discharge control (1 13) operable by a user allowing water to be controllably discharged from said expandable water reservoir via said nozzle,

- a filling station (400), said filling station comprising:

- a water inlet (401),

- a water pump (402) to pressurize said water, wherein the inlet of said pump is in communication with said water inlet,

- preferably, an electrical drive to electrically drive said pump, and

- a water outlet (406 to discharge water pressurized by said pump, said water outlet in communication with the water outlet of said pump,

wherein said water inlet of the toy water gun is attachable to said water outlet of the filling station so as to allow communication between said water outlet and water inlet, and wherein said water inlet of the toy water gun is detachable from said water outlet.

20. Toy water gun system comprising:

- a handheld toy water gun comprising:

- a water circuit comprising:

- a water discharge outlet,

- a first connector having an inlet of said water circuit, - a cartridge having a cartridge housing and being provided with a water reservoir adapted to store a water volume therein, e.g. a pre-pressurizable water reservoir adapted to store water therein under pressure, said cartridge further being provided with a second connector having a water port of said water reservoir,

and wherein said second connector is provided with a second valve assembly,

wherein said first and second connectors are adapted to be connected to one another by advancing the cartridge along a connection axis relative to the toy water gun into an advanced position of the cartridge and to be disconnected from one another to be retracting the cartridge along said connection axis,

wherein the second connector comprises a base mounted to said housing,

and wherein the second valve assembly comprises a rotary valve member journaled to the base,

wherein the rotary valve member, in a first angular position thereof about the connection axis relative to the base closes the water port of the cartridge, and in a second angular position thereof about the connection axis relative to the base opens the water port of the cartridge.

21. Toy water gun system comprising:

- a handheld toy water gun comprising:

- a water circuit comprising:

- a water discharge outlet,

- a first connector having an inlet of said water circuit,

- a cartridge having a cartridge housing and being provided with a water reservoir adapted to store a water volume therein, said cartridge further being provided with a second connector having a water port of said water reservoir,

wherein said cartridge is releasably connectable to said toy water gun and said first and second connectors are connectable to one another so as to establish a connection between the water port of the water reservoir of the cartridge and the inlet of the water circuit of the toy water gun,

and wherein said second connector is provided with a second valve assembly,

wherein the toy water gun comprises a cartridge carrier that is manually translatable along said connection axis and is adapted to receive said cartridge therein in a retracted position of said carrier and adapted to be translated together with the cartridge to said advanced position of the cartridge.

22. Toy water gun system comprising:

- a toy water gun comprising:

- a water circuit comprising:

- a water discharge outlet,

- a first connector having an inlet of said water circuit,

wherein said cartridge is releasably connectable to said toy water gun and said first and second connector are connectable to one another so as to establish a connection between the water port of the water reservoir of the cartridge and the inlet of the water circuit of the toy water gun,

and wherein said second connector is provided with a second valve assembly,

wherein the second connector comprises a base mounted to said housing,

wherein the rotary valve member, in a first angular position thereof about the connection axis relative to the base closes the water port of the cartridge, and in a second angular position thereof about the connection axis relative to the base opens the water port of the cartridge, wherein the toy water gun, e.g. the first connector, comprises a first coupling portion, and wherein the rotary valve member comprises a second coupling portion which, when the rotary valve member is in said first angular position, is adapted to couple to said first coupling portion upon said axial advancing of the cartridge along a connection axis relative to the toy water gun into said advanced position,

wherein the toy water gun, e.g. the first connector, is provided with an L-shaped bayonet groove,

and wherein the cartridge is provided with a mating bayonet boss, wherein said groove has a longitudinal portion parallel to said connection axis and a locking portion at an end of said longitudinal portion and transverse to said longitudinal portion, wherein said bayonet structure is arranged such that, upon advancing said cartridge to said advanced position thereof, said boss slides through said longitudinal portion thereby preventing manual rotation of the cartridge and thus said manually caused rotation of the rotary valve member from said first angular position into said second angular position, and such that, upon having reached said advanced position of the cartridge and said user manually rotating the cartridge and thus causing said rotation of the rotary valve member from said first angular position into said second angular position, the boss slides through the locking portion of the bayonet groove thereby opening the water port and preventing a retraction of the cartridge along said connection axis.

23. Toy water gun system comprising:

- a toy water gun comprising:

- a water circuit comprising:

- a water discharge outlet, - a discharge control operable by a user allowing water to be controllably discharged from said water reservoir via said water discharge outlet,

- multiple first connectors, each having an inlet of said water circuit,

- multiple cartridges, each having a cartridge housing and being provided with a water reservoir adapted to store a water volume therein, said cartridge further being provided with a second connector having a water port of said water reservoir,

wherein each first connector is provided with a first valve assembly, wherein said first valve assembly is adapted to close said inlet of said water circuit in case said cartridge is disconnected from the toy water gun, and to open said inlet of said water circuit in case said cartridge is connected to said toy water gun,

and wherein each second connector is provided with a second valve assembly,

24. A cartridge for use with a toy water gun having a water circuit comprising:

- a water discharge outlet,

- a first connector having an inlet of said water circuit,

wherein said cartridge has a cartridge housing and being provided with a water reservoir adapted to store a water volume therein, said cartridge further being provided with a second connector having a water port of said water reservoir,

wherein the second connector comprises a base mounted to said housing, and wherein the second valve assembly comprises a rotary valve member journaled to the base,

25. A cartridge for use with a toy water gun having a water circuit comprising:

- a water discharge outlet,

- a first connector having an inlet of said water circuit,

wherein said cartridge is provided with a pre-pressurizable water reservoir arranged within said housing, e.g. with an expandable body, e.g. a body of resilient material, e.g. silicone rubber, that is expanded upon feeding pressurized water into said expandable body and that is self-compressing and/or the cartridge being provided with compression means associated with the water reservoir,

wherein a variable volume air chamber is delimited between said housing and said expandable water reservoir, wherein said housing is provided with said passage and an airflow operated sound-producing device is adapted to provide a water discharge related sound as in response to the compression of the expandable water reservoir from an expanded state to a relaxed state an air flow occurs through the passage from the exterior into said variable volume air chamber.

26. A toy water gun water reservoir assembly (900,1000), comprising:

- a variable volume water chamber having an inlet and an outlet for water, optionally a combined inlet and outlet for water, e.g. said combined inlet and outlet being provided with a self-closing valve, e.g. a slit valve or a duckbill valve,

- a variable volume vacuum chamber,

- a vacuum chamber piston member bounding said variable volume vacuum chamber, wherein said water piston member and said vacuum chamber member are mechanically connected and form a piston assembly, - a user operable locking device adapted to lock and unlock said piston assembly, at least, or only, in the filled position of the water piston member,

so that, in use, filling water into the variable water chamber, e.g. from a pressurized water source, e.g. provided with a pump, or from a non-pressurized water source by moving the piston assembly to the filled position, entails, e.g. causes, that said piston assembly moves with said water piston thereof into the filled position, in which process a vacuum or deeper vacuum is caused in the vacuum chamber, wherein the user operable locking device allows to lock said piston assembly as said water piston in said filled position, e.g. automatically causing said locking when in said filled position, and wherein said user operable locking device is unlockable by the user so that the vacuum acting on the vacuum chamber piston member causes the water in the water chamber to be pressurized in order of expulsion thereof from the water reservoir assembly.

27. A toy water gun water reservoir assembly (900,1000) comprising:

- a variable volume water chamber (1001) having an inlet (1003) and an outlet (1004) for water,

- a reciprocable water piston member (1005) bounding said variable volume water chamber, said water piston member being reciprocable between an emptied position where the water chamber (1001) is empty and a filled position wherein the water chamber (1001) is filled with water,

- a variable volume vacuum chamber (1010),

- a vacuum chamber piston member (1015) bounding said variable volume vacuum chamber, wherein said water piston member and said vacuum chamber piston member are

mechanically connected and form a piston assembly (1020),

- a user operable locking device (1030) configured to lock and unlock said piston assembly (1020), at least in the filled position of the water piston member (1005),

wherein displacement of the water piston member (1005) from the emptied position to the filled position in the course of filling water into the variable volume water chamber causes a vacuum or a deeper vacuum in the variable volume vacuum chamber (1010),

wherein the user operable locking device (1030) is configured to lock said piston assembly (1020) in said filled position of the water piston member, e.g. automatically causing said locking when said filled position is reached,

and wherein said user operable locking device (1030) is unlockable by the user so that vacuum in the variable volume vacuum chamber (1010) acts on the vacuum chamber piston member (1015) and thereby on the piston assembly (1020) which causes the water piston member (1005) to pressurize the water in the water chamber (1001) and expel said water via said outlet (1004) of the variable volume water chamber, e.g. via a duckbill valve (1040).