AU2015100607A4 - Water Hose - Google Patents

Abstract

A self-expanding water hose including a first tube made from an elastic and water tight material wherein the first tube is adapted to expand longitudinally and laterally when pressurised water is filled in and contract when not pressurised; and a second tube made from an elastic and flexible material wherein the first tube is located inside the second tube and the first tube and the second tube are attached to one another at their distal ends and the second tube is adapted to expand longitudinally and/or laterally when the first tube inside the second tube expands.

Description

1 Water hose 5 The present invention relates to a self-expanding water hose. More specifically, the invention relates to a self-expanding water hose to be used outdoors, for example, in the garden or in the driveway. 10 Hoses for different purposes are long known in the industrial as well as in the private sector. In the private sector, they are most often used in the garden to water plants, or washing the car in the driveway, or filling up inflatable swimming pools. 15 Commonly, hoses are made from rubber or other resilient flexible materials and have the purpose to guide a fluid, mostly water, from one place to another. Thereby, the resilient flexible materials allow the hoses to be durable, but at the same time to be flexible enough not to represent a stiff pipe. Hence, the hoses are capable of being bent or flexed or 20 twisted without breaking. However, using resilient flexible materials makes it difficult to store the hoses, in particular in a compact format in a limited space. Because of this, the manufactures often try to find a compromise between durability and flexibility. However, if the hoses are made from too thin materials and do not possess a certain degree of 25 inflexibility, they tend to kink quite a lot and are also vulnerable to be punctured. Vice versa, if they are made from a thick material and are therefore durable, they are cumbersome to store because they are quite stiff. 30 There are water hoses known, which try to overcome this problem. For example one known hose includes an elongated flexible tube formed in extendable and contractable helical coils. The coiled tube permits a wide range of extension during use. However, even so the known hose uses up less space as commonly known hoses, this hose may still be quite 35 cumbersome to handle.

2 Furthermore, there are flexible hoses known, which contract on themselves when not pressurized, so that they use less space during storing. Thereby, the flexible hoses comprise a thin tubing and spiral 5 reinforcement means. The thin tubing is tapered in its thickness in the longitudinal direction between two adjacent spiral turns of the reinforcement means so that the tubing may bend inwardly and form pleats, these pleats incline toward the axis of the hose and advance along the inner surface of the reinforcement means in its contracted form. 10 When the hose is pressurized, the pleats are flattened and push the spiral turns apart, such that the hose expands. When the hose is de-pressurized the spiral reinforcement means contract the hose. Such a hose may be easy to store when not in use and may also be quite easy to handle, however, it exhibits the disadvantage that when it is dragged through the 15 garden or over the driveway, dirt may come in between the spiral turns and may damage the thin tubing. If the tubing is reinforced to avoid this from happening, then the hose is not flexible anymore and it will lose the aforementioned advantage. 20 Therefore, it is the object of the present invention to provide a water hose, which does not exhibit the aforementioned disadvantages. Hence, a water hose, which is durable, but at the same time can be stored away in limited spaces when not in use and is easy to handle. 25 This object is solved by a water hose according to independent claim 1 of the current invention. Thereby, a water hose according to the invention comprises a first tube, made from an elastic and water tight material, wherein the first tube is 30 adapted to expand longitudinal and laterally when pressurized and contract when not pressurized. An elastic material is a material which allows longitudinal and/or lateral expansion due to the properties of the material. Thereby, the amount of longitudinal and/or lateral expansion is defined by the coefficient of elasticity of the material, also known as 3 elastic modulus, or modulus of elasticity, which defines an objects tendency to be deformed elastically (i.e., non-permanently) when a force is applied to it. The lower this coefficient of elasticity is, the easier it is to deform the material. Hence, the same amount of force applied to two 5 different materials with different coefficients of elasticity cause the material with the lesser coefficient of elasticity to be deformed more than the one with the higher coefficient of elasticity. For example, rubber has a lower coefficient of elasticity as Nylon, hence if the same force is applied to both materials, the rubber will deform more than the Nylon. 10 The first tube is made from an elastic material, which may be characterized by a first coefficient of elasticity. The first tube is adapted to expand longitudinal and/or laterally when force is applied. In a first state - in which no force is applied - the first tube will have a first length 15 and/or a first diameter and in a second state - in which force is applied - the first tube will have a second length and/or second diameter. The longitudinal expansion of the first tube is thereby defined by the expansion of length of the first tube from the first length to the second length, wherein the second length is longer than the first length. 20 Furthermore, the lateral expansion is defined by the expansion of diameter of the first tube from the first diameter to the second diameter, wherein the second diameter is larger than the first diameter. The expansion from the first length to the second length and/or from the first diameter to the second diameter is thereby characterized by the 25 coefficient of elasticity of the material from which the first tube is made and the force applied. The expansion of length and/or diameter of the first tube may be caused by pressurizing the first tube, i.e. increasing the pressure inside the first tube, wherein this pressure exerts a force onto the inner surface of the first tube causing it to expand. Increasing the 30 pressure inside the first tube may, for example, be achieved by filling the first tube with water, such that the first tube may have its first length and/or first diameter when no water is introduced into the first tube and may have its second length and/or diameter when water is introduced into the first tube. If the force exerted by the pressure is high enough to 4 overcome the reset force of the elastic material from which the first tube is made, the first tube will expand in length and/or diameter until the reset force equals the exerted force. 5 Further, the water hose according to the invention also comprises a second tube, made from an elastic and flexible material, wherein its elasticity may be characterized by a second coefficient of elasticity. The second tube is adapted to expand longitudinal and/or laterally when force is applied. Hence, the second tube will have in a first state - in 10 which no force is applied - a first length and/or a first diameter and in a second state - in which force is applied - a second length and/or second diameter. The longitudinal expansion of the second tube is thereby defined by the expansion of length of the second tube from the first length to the second length, wherein the second length is longer than the 15 first length. Furthermore, the lateral expansion is defined by the expansion of diameter of the second tube from a first diameter to a second diameter, wherein the second diameter is larger than the first diameter. 20 According to the invention, the first tube is located inside the second tube and the two tubes are connected to each other at their distal ends. Hence, when the first tube is pressurized and due to it being elastic, it will expand longitudinal and/or laterally, this in turn means the outer surface of the first tube will at one point reach the inner surface of the 25 second tube and will exert a force upon the second tube. This force then expands the second tube longitudinal and/or laterally until a point where the force exerted upon the second tube by the first tube is not strong enough to cause further expansion, because the force exerted does not overcome the reset force anymore. 30 The total expansion of the water hose can thereby be controlled by the coefficient of elasticity ratio for the first tube and the second tube. For example, if the second tube has a high coefficient of elasticity, then the force exerted upon it by the first tube must be high enough to deform it, 5 this can be achieved by using a low coefficient of elasticity for the material of the first tube, because then it can expand easily, such that enough force can be exerted upon the second tube. Vice versa, if the coefficient of elasticity of the first tube is high, then the force caused by 5 the pressure inside the first tube may only expand the first tube to a certain degree, such that also only a certain degree of force can be exerted upon the second tube, which in turn may have the same or even a smaller coefficient of elasticity as the first tube. Also, the total expansion of the water hose can be controlled by the diameter ratio of 10 the first tube and the second tube. For example, the first tube in the non expanded state may have a smaller diameter as compared to the second tube. Once the first tube is pressurized, it may laterally expand, however, if its initial diameter was small compared to the one of the second tube, it will first need to bridge the diameter gap between the diameter of the 15 first tube and the second tube, before the outer surface of the first tube can contact the inner surface of the second tube and exert a force upon it. The total expansion of the water hose can also be controlled by the length ratio of the first tube and the second tube. For example, the first tube may have a length which is smaller than the length of the second 20 tube. In this case, due to the two tubes being connected to each other at their distal ends, the second tube will be contracted to the same length as the first tube in the non-expanded state, which will mean its material will wrinkle around the first tube. Once the first tube is pressurized, it will expand in length, which at first causes the material of the second 25 tube to become flatten, until the first tube has expanded to the length of the second tube. Then, if the first tube still expands in length, it will exert a force upon the second tube, which causes the second tube to stretch. This stretching will go on as long as the reset force of the material of the second tube is smaller than the force exerted upon it by the longitudinal 30 expansion of the first tube. Consequently, the total expansion of the water hose can be controlled by one or a combination of the aforementioned ratios.

6 The water hose according to the invention has the advantage that when it is pressurized, it will expand on its own and when it is de-pressurized it will contract on its own. Due to the fact that both tubes expand and contract, the water hose in the de-pressurized state is quite small as 5 compared to the pressurized state and can be easily handled and stored away. Furthermore, that both tubes are elastic and contract has the advantage that the first tube is faster de-pressurized, since water is pushed out the first tube due to the contraction of both tubes working together. Furthermore, having a two layered water hose exhibits the 10 advantage that the water hose is durable. This is due to that fact that even so the second tube is punctured, the water hose is still functional, since water is only transported by the first tube located inside the second tube. The second tube provides an outer durable sheath for the first tube. 15 In one preferred aspect of the invention, the first coefficient of elasticity is less than the second coefficient of elasticity. Hence, the first tube has a lower coefficient of elasticity as the second tube and as a result expands more than the second tube when the same force is applied. This has the advantage that the second tube acts as durable sheath for the first tube 20 and limits the expansion of the first tube to a certain degree, which in turn means it prevents the first tube from rupturing. The second tube may thereby have a certain degree of elasticity as well, such that it also expands to a certain degree when the first tube expands inside and exerts a force onto the second tube. This has the advantage that the total length 25 of the water hose can be as long as the expanded length of the second tube, whereas in the contracted state the water hose is compact and has the lengths of the lesser of the two tubes. For example, the first tube may in the non-expanded state have a length which is smaller than the length of the second tube in the non-expanded state. Due to the two tubes being 30 connected at their distal ends, the length of the second tube will be the same as the length of the first tube in the non-expanded state, because the first tube will contract the opposing distal ends. Once the first tube is pressurized, it expands longitudinal and/or lateral and the opposing distal ends are pushed apart, which in turn means the length of the first 7 tube increases. Due to the fact that the distal ends of the two tubes are connected, also the opposing distal ends of the second tube are pushed apart. This pushing apart can continue until the force exerted upon the second tube by the expanding first tube is equal to the reset force of the 5 material of the second tube. Hence, the second tube limits the expansion of the first tube and thereby preventing it from rupturing. If the first tube is de-pressurized the two tubes will contract, since the first tube has a length which is smaller than the length of the second tube, the water hose will contract to this length. It is however also contemplated that the 10 two tubes may have the same length in the non-expanded state and the expansion limitation is for example solely controlled by the ratio of the coefficient of elasticity of the first tube and the second tube, or any other of the aforementioned ratios by which the expansion can be controlled. 15 In one preferred aspect of the invention, the first tube and the second tube are attached to one another by a first coupler at their first distal ends and a second coupler at their second distal ends. Thereby, the couplers may be clamped with the first tube and the second tube through a snap structure. Alternatively or additionally, the couplers may 20 comprise thread means, such that the first tube and the second tube can be secured to one another by ease of the thread means. Also, the couplers may be glued to the distal ends, securing the first tube to the second tube. However, also other means for securing the couplers to the distal ends are contemplated by a person skilled in the art. The first coupler 25 may be adapted to couple the water hose to a source of pressurized water and the second coupler may be adapted to couple the water hose to appliances, or to a water flow restrictor. Thereby, the couplers may be commonly known male and female couplers as used for gardening hoses, and may be capable of being connected to other garden appliances, for 30 example, a sprinkler nozzle or a car wash brush. The couplers may be made out of plastic or metal. The couplers may at their end comprise threads with commonly known thread measures to be connected to appliances. However, also other couplers and coupling means are contemplated in order to connect the water hose to sources of 8 pressurized water on one side and to appliances on the other. It is also contemplated that the couplers can be used to connect several of the water hoses together. Appliances may encompass a flow restrictor by which the flow of water through the appliances and in turn through the 5 first tube can be limited. Such a flow restrictor may be a valve that permits, limits, and/or stops the flow of water through the appliances and as such through the first tube. It is also contemplated that such a flow restrictor is an extra part connected in between the coupler and the appliances, or is part of the coupler itself. For example, the at least one 10 coupler may comprise an internal valve that permits, limits, and/or stops the flow of water through the first tube. Alternatively or additionally, the coupler may comprise a flow restrictor in form of a water stopper or valve for retaining the water inside the first tube until the water stopper is released. This may be advantageously, when the water hose at one side 15 is already connected to a pressurized water source, but the other end is not connected to an appliances. In this case in order to avoid water leakage, the water stopper may be employed. The water stopper may thereby either be manually released or it may be automatically released when an appliances is connected to the coupler. Furthermore, the water 20 stopper may not release until a predefined pressure is built up in the first tube and the first tube has expanded, this supports the increase of pressure inside the first tube and ensures additionally that the first tube is always substantially expanded longitudinal as well as laterally. For this purpose, the water stopper may comprise a pressure actuated valve, 25 which only releases if the pressure inside the first tube is high enough. A person skilled in the art will however also recognize that other types of couplers and flow restrictors may be used. In another preferred aspect of the invention, the water hose may 30 comprise at least one circumferential limiter, wherein the at least one circumferential limiter is adapted to limit the lateral expansion of the first tube when pressurized. Pressure inside the first tube can be built up, for example, by blocking one end of the first tube and connecting the other end to a pressurized water source. However, during normal use 9 water is not only introduced into the water hose, but at the same time also drained from it. In order to ensure that also in this case the first tube remains pressurized, hence, expanded longitudinal as well as lateral, the circumferential limiter may, at least for a defined length, 5 prevent the first tube to expand to maintain pressure inside the first tube. Thereby, the at least one circumferential limiter may be placed around the first tube and/or the second tube. Alternatively, the at least one circumferential limiter may be placed around the first tube between the first tube and the second tube, such that its inner surface contacts 10 the outer surface of the first tube and its outer surface contacts the inner surface of the second tube. The circumferential limiter may thereby have the form of a cylinder, which inner diameter substantially equates to the diameter of the first tube in the non-expanded state and its outer diameter substantially equates to the diameter of the second tube in the 15 non-expanded state. When the first tube is pressurized, the circumferential limiter, which is placed between the distal ends of the two tubes presents a barrier for the introduced water, which in turn leads to a ram pressure built up, such that the pressure is high enough to expand the first tube longitudinal and/or laterally, even if water is 20 flowing through it. The amount of ram pressure is thereby dependent upon the inner diameter of the circumferential limiter, which hence can also be chosen to be smaller than the diameter of the first tube in the non-expanded state, in order to increase the ram pressure built up. In order to fixate the position of the circumferential limiter, it may be glued 25 and/or fused in place. For example, an epoxy resin may be used. Alternatively or additionally, the circumferential limiter may be heat fused to the tubes. Thereby, the circumferential limiter may for example be made out of plastic, which when heated can be bonded with the tubes. For example, if the circumferential limiter is placed around the second 30 tube, its inner surface may be fused and/or glued to the outer surface of the second tube only. If it is placed inside the second tube, then the inner surface of the circumferential limiter may be fused and/or glued to the inner surface of the first tube and the outer surface of the circumferential 10 limiter may be fused and/or glued to the inner surface of the second tube. In yet another preferred aspect of the invention, the first tube is made 5 out of an elastic material that is water tight and resistant. Resistant in this case means that the material is able to tolerate environmental conditions and the forces applied to it, at least to a certain degree. For example, the first tube may be made out of rubber, hence an elastomer type polymer, wherein the polymer has the ability to return to its original 10 shape after being stretched - elongated / expanded - or in any other way or form being deformed. The first tube may also be made out of silicone or latex, which possess similar physical characteristics. These elastic materials allow the first tube to elongate longitudinal as well as laterally, but at the same time provides quite a durability and resistance. 15 Furthermore, the choice of the material of the first tube defines the longitudinal and lateral elongation of the first tube. Preferably, a material is used, which allows the first tube to elongate longitudinal at least three times its length, when pressurized, such as that enough force can be exerted upon the second tube to also expand the second tube 20 longitudinal. However, also other ratios and materials may be contemplated by a person skilled in the art. The first tube can also comprise at its outer surface, hence the surface facing the inner surface of the second tube, a coating which has a low friction coefficient or reduces the friction of the material, such that the first tube can easily 25 move inside the second tube. In another preferred aspect of the invention, the elastic and flexible material of the second tube may be a stretchable material. Stretchable in this sense means a material which is capable of resuming its original 30 shape after being stretched or elongated. For example, the material may be a woven material made out of durable strings and elastic threads. The material may be a fabric made of yarns containing an elastic material. Also, the material may be made with strands or inserts of elastic. The material may be made by weaving or felting or knitting or crocheting 11 natural or synthetic fibers, some of which may be non-elastic and some of them may be elastic, or at least may have different elasticities. For example, the material may be made out of 60% Nylon strings and 40% Elastane threads. Furthermore, the material may also be made out of up 5 to 55% Nylon strings, up to 5% Polyester strings, and up to 40% of Elastane threads. For the elastic threads for example Spandex may be used, which is a type of Elastane. Spandex is a synthetic fiber that is elastic and strong. It is a polyurethane-polyurea copolymer. However, also other materials and material compositions are contemplated. The 10 strings and threads may be braided or woven to form the material used for the second tube. Using a woven material has also the advantage that by the weaving technique used, it can be controlled in which direction the material can be deformed and as such in which direction the second tube is expandable. For example, the elastic threads may be weaved into 15 the material as such that only a longitudinal expansion of the second tube is possible or only a lateral expansion. Furthermore, it is also possible that the material is woven as such that the second tube can be deformed more in the longitudinal direction as in the lateral direction, or vice versa. The second tube can also be formed by a flat woven material, 20 which is glued or fused together to form the tube. Since the water is transported by the first tube, which is water tight, the material used for the second tube does not need to be water tight. However, the inner surface of the second tube, hence the surface facing the outer surface of the first tube, may also be coated with a water tight coating or 25 membrane, such that in the event that the first tube ruptures or leaks, no water leakage occurs. Furthermore, this inner coating or membrane can have a low friction coefficient, such that the first tube can easily move within the second tube. However, also other elastic and flexible materials as the ones described above are contemplated by a person skilled in the 30 art. The second tube can thereby be also made out of a material mixture. Also the second tube can be made out of several parts.

12 The above features and advantages of the present invention will become apparent from the following detailed description when taken with the accompanying drawings in which 5 FIG 1 shows a schematic of an embodiment example of the water hose according to the present invention in the contracted state; FIG 2 shows a partially transparent schematic of the 10 embodiment example of the water hose according to the present invention as shown in figure 1 in the expanded state; and FIG. 3 shows a schematic of an embodiment example of the 15 water hose according to the present invention with couplers connected to the distal ends. Figure 1 shows an embodiment example of a water hose 1 according to the invention in the contracted state. Thereby, a first tube 2 is located 20 inside a second tube 3 which forms a sheath for the first tube 2. The first tube 2 is made out of an elastic material, which in the non-expanded state has a first length, which equates in the shown embodiment example to length L 1 . The second tube 3 is also made out of an elastic material, which may have a different coefficient of elasticity as compared to the 25 first tube 2. In the here shown embodiment example, the length of the second tube 3 in the non-expanded state is larger than the length L 1 of the first tube 2. However, due to the two tubes 2, 3 being connected at their distal ends, the material of the second tube 3 wrinkles, in order to accommodate its excess length on the length L 1 of the first tube 2. 30 However, the second tube 3 may also have the same length L 1 as the first tube 2. In this case the material of the second tube would be smoothly surrounding the first tube 2.

13 Further, in the embodiment example as shown in figure 1, the first tube 2 is attached to the second tube 3 at at least one further position along the length L 1 , namely by ease of a circumferential limiter 4, which in the here shown embodiment example is located within the second tube 3, such 5 that the inner surface of the circumferential limiter 4 is fused and/or glued to the outer surface of the first tube 2, and the outer surface of the circumferential limiter 4 is fused and/or glued to the inner surface of the second tube 3. Thereby, the circumferential limiter 4 restricts the lateral expansion of the first tube 2 within the second tube 3 - as shown in 10 figure 2. At the remaining positions, the first and second tubes 2, 3 are unattached and can move freely relatively to each other. In order to enhance this free motion, the first tube 2 may comprise at its outer surface a coating with a low friction coefficient. Alternatively or additionally, the second tube 3 may comprise a similar coating on its 15 inner surface. The coating of the second tube 3 may thereby also be water tight in order to prevent any leakage if the first tube 2 ruptures or leaks. The first tube 2 may be pressurized by blocking one end of the first tube 20 2, for example, by means of connecting it to a coupler (here not shown) and a flow restrictor (here not shown) which allows to control the flow of water through the first tube 2. The other end of the first tube 2 may be connected to a pressurized water source, for example, connecting it to a water tab by ease of a further coupler (here not shown). When water is 25 then filled into the first tube 2, a pressure will built up in the first tube 2. This causes the first tube 2 to expand in diameter as well as in length. Since the distal ends of the first tube 2 and the second tube 3 are connected, the lengthwise expansion of the first tube 2 will also be undertaken by the second tube 3. Hence, the wrinkles in the material of 30 the second tube 3 will flatten and the water hose 1 will expand in length from L 1 in the contracted state to length L 2 in the expanded state - as shown in figure 2. Thereby, the lengthwise and lateral expansion of the first tube 2 is limited by the second tube 3 and its characterizing coefficient of elasticity. When the first tube 2 expands inside the second 14 tube 3, it will increase in diameter and length. The expansion laterally causes the outer surface of the first tube 2 - when its diameter matches the one of the second tube 3 - to exert a force upon the inner surface of the second tube 3, which in turn causes the second tube 3 to expand as 5 well. However, this expansion is characterized by the coefficient of elasticity of the second tube 3 and how much it will be laterally deformed by the force exerted upon it. The first tube 2 also expands longitudinal, which causes a force to be exerted upon the second tube 3, which stretches the second tube 3. At first the longitudinal expansion of the 10 first tube 2 is not limited by the second tube 3, since its overall length is larger than length L 1 of the first tube 2, hence, at first the longitudinal expansion of the first tube 2 only causes the wrinkles of the second tube 3 to flatten. If the wrinkles have flatten and the first tube 2 has expanded to the length of the second tube 3, a force will be exerted upon the 15 second tube 3, which causes the second tube 3 to be stretched longitudinally. This stretching is again characterized by the coefficient of elasticity of the second tube 3 and how much it will be longitudinally stretched by the force exerted upon it. 20 Figure 2 shows a partially transparent schematic of the embodiment example of the water hose 1 as shown in figure 1, but in the expanded state. Thereby, the part which is shown partially transparent discloses the inside of the second tube 3 at the circumferential limiter 4. In the shown embodiment example, the second tube 3 characterized by its 25 coefficient of elasticity has limited the expansion of the first tube 2 to a total length of L 2 and a total diameter of di, due to the force exerted upon the second tube 3 by the first tube 2 being now to small to further expand the second tube 3. In this case the force exerted upon the second tube 3 by the first tube 2 equals the reset force of the material used for 30 the second tube 3. As can be seen from figure 2, the circumferential limiter 4 limits the lateral expansion of the first tube 2 to a diameter d 2 along the extension of the circumferential limiter 4. The predefined diameter d 2 is needed to 15 maintain a pressure inside the first tube 2 even if water is drained from one end - here the right hand side. Due to the circumferential limiter 4 limiting the diameter to d 2 , a ram pressure is built up inside the first tube 2. This ram pressure causes the first tube 2 to dilate to diameter di and at 5 the same time also causes the first tube 2 to stretch longitudinal to length L 2 . It is preferred that the circumferential limiter 4 is positioned close to the distal end from which the water is drained, such that upstream of the circumferential limiter 4 enough pressure can be built up to expand the first tube 2, but still is far enough away from the end 10 from which water is drained not to make it un-flexible. Figure 3 shows a schematic of an embodiment example of the water hose 1 according to the present invention with couplers 5, 6 connected to the distal ends of the second tube 3 and the first tube 2 - here not shown, 15 due to being located inside the second tube 3. By ease of coupler 5, the water hose 1 may be connected to a source of pressurized water and by ease of coupler 6, the water hose 1 may be connected to an appliances, as for example a sprinkler nozzle (here not shown). The coupler 6 can thereby comprise a water stop functionality, which prevents water to 20 flow out this end of the water hose 1 until an appliances is connected. Alternatively or additionally, the coupler 6 may also comprise a water flow restrictor, for example, in form of a valve, which permits to regulate the flow of water through the water hose 1. Alternatively or additionally, the coupler 6 may also be connected to an additional flow restrictor 25 (here not shown). Furthermore, the circumferential limiter 4, placed within the second tube 3, is indicated. The circumferential limiter 4 allows a built up of ram pressure inside the first tube 2 when water is drained from the water hose 1, whereby this ram pressure causes the water hose 1 to remain substantially in the expanded state even so water 30 is drained from it. Even so only one circumferential limiter 4 is shown in the embodiment example, it is contemplated that also more than one circumferential limiter 4 can be used.

Claims (5)

1. A water hose, comprising 5 a first tube, made from an elastic and water tight material, wherein the first tube is adapted to expand longitudinal and laterally when pressurized water is filled in and contract when not pressurized; and a second tube, made from an elastic and flexible material, wherein the first tube is located inside the second tube, and the first tube and the 10 second tube are attached to one another at their distal ends, and the second tube is adapted to expand longitudinal and/or laterally when the first tube inside the second tube expands.

2. The water hose according to claim 1, wherein the coefficient of 15 elasticity of the first tube is less than the coefficient of elasticity of the second tube.

3. The water hose according to any of the preceding claims, wherein the first tube and the second tube are attached to one another by a first 20 coupler at their first distal ends and a second coupler at their second distal ends, the first coupler is adapted to fluidly couple the first tube to a pressurized source of water, and the second coupler is adapted to couple the first tube to a water flow restrictor, or the second coupler comprises a water flow restrictor for restricting the flow of water through the first 25 tube.

4. The water hose according to any of the preceding claims, wherein the water hose further comprises: at least one circumferential limiter, wherein the at least one 30 circumferential limiter is adapted to limit the lateral expansion of the first tube when pressurized along the length of the circumferential limiter. 17

5. The water hose according to claim 4, wherein the circumferential limiter is positioned between the distal ends of the first tube and the second tube and the circumferential limiter connects the first tube to the second tube at at least one further position between the distal ends, 5 wherein an inner surface of the circumferential limiter is fused and/or glued to an outer surface of the first tube and an outer surface of the circumferential limiter is fused and/or glued to an inner surface of the second tube.