GB2390341A

GB2390341A - Trolley having auxilliary wheel to aid directional control

Info

Publication number: GB2390341A
Application number: GB0215541A
Authority: GB
Inventors: Gordon Robert Creighton
Original assignee: Individual
Current assignee: Individual
Priority date: 2002-07-04
Filing date: 2002-07-04
Publication date: 2004-01-07
Anticipated expiration: 2022-07-04
Also published as: GB2390341B; GB0215541D0

Abstract

A trolley has pairs of front and rear wheels disposed on a chassis, the trolley has at least one further, auxiliary, wheel that is preferably disposed between the front and rear of the chassis. The wheel is preferably attached to handle means so that the trolley operator can move the auxiliary wheel in and out of contact with the ground. The auxiliary wheel when contacting the ground aids movement of the trolley by helping to arrest sideways movement.

Description

1 239034 1

DIRECTION CONTROL FOR WHEEL SUPPORTED DEVICES / TROLLEYS

DESCRIPTION

This invention is directed primarily to arresting the frustrating and awkward sideways movement of castor supported trolleys/devices when attempting to push them in a particular direction, such as luggage trolleys or supermarket shopping trolleys. The difficulty in controlling such devices could, apart from being irritating, lead to a compensatory and/or dangerous situation such as the trolley running into and damaging a car or a person.

This invention therefore relates to devices having supporting wheels or castors which are in contact with a surface i.e. the ground and where the device has at least one auxiliary wheel (normally retracted) which can be deposited to contact the surface and released as needed to control the direction of the device. The auxiliary wheel is typically arranged so that it cannot turn about an essentially vertical axis and it is set to only roll in the longitudinal direction of the trolleyIdevice. This means that when the auxiliary wheel is made to contact the ground surface it will effectively only allow the trolley/device to run in the longitudinal direction. Steering however is still possible as the trolley/device can articulate about the fixed auxiliary wheel/s. The auxiliary wheel is normally held retracted by a tension device i.e. a spring and operated by a lever to deploy the auxiliary wheel such that when the lever is released the auxiliary wheel retracts to its original position clear of the ground surface. This allows the original features of the trolley/device to be maintained - inparticular maintaining the sideways movement. A diagrammatic representation of this invention is given in Figures 1, 2 and 3.

Figure 1 depicts a traditional trolley.

Figures 2 and 3 show the rear of the trolley only but with the auxiliary wheel attached/pivoted to the left-hand rear leg (which supports the castor support wheel) such that the auxiliary wheel can move up and down.

Figure 2 shows the normal castor support wheel A and the fixed auxiliary wheel B in the normally retracted position clear of the ground allowing the trolley to behave in the traditional way.

Figure 3 shows the normal castor wheel A and the auxiliary wheel B deployed to the ground in the direction of the arrow D thus preventing sideways movement of the trolley due to wheel B being a fixed type as opposed to a castor type.

There are many ways to use the invention as the auxiliary wheel could be positioned anywhere providing it can touch the ground i.e. adjacent or remote or in front or behind or beside any of the traditional support wheels and more than one auxiliary wheel could be used.

The mechanism to deploy the auxiliary wheel/e can be arranged in many ways.

Figures 4,5 and 6 show some of these methods in diagrammatic form.

Figure 4 depicts a mechanical method where H is the handle of the trolley. An "Ln shaped member M pivoted in the region of the bend T forms the operating lever V and to operate the auxiliary wheel, the user pulls the lever V towards the handle H of the trolley. The "Lo shaped member M is linked to a bar R which consequently moves

-2 in the direction of the arrow D thus deploying the auxiliary wheel. An enlarged view of the lever is shown in Figure 7. This method similarly could be arranged such that the lever V is also the handle of the trolley/device and this is shown in Figure 5.

It can be seen in Figure 5 that pushing the handle H forward (direction N) to push the trolley also moves the handle forward relative to the trolley. The auxiliary wheel is therefore deployed in similar manner to that in the previous example represented by Figure 4. In each of the mechanisms represented in Figures 4 and 5, J represents a guide for the bar R. More than one guide can be used typically located at each end of bar R. Also in Figures 4 and S the retraction springs have been omitted.

Figure 6 depicts a cable-operated mechanism where a fixed arm S is attached to the chassis or a member of the trolley F. Attached to the arm S is the outer sheath of a sheathed cable K. The inner cable C protrudes from the sheath and is attached to a pivoted arm P to which at the opposKe end is attached the auxiliary wheel. A spring holds the auxiliary wheel retracted and is ideally situated between the fixed arm S and pivoted arm P. When the inner cable is pulled via a remote lever it intum deploys the auxiliary wheel. Releasing the lever allows the auxiliary wheel to retract.

There are many other ways of deploying the auxiliary wheel/e and the method chosen will depend on the design of the chassis of the trolley/device and the preferences of the designer/user.

The retraction tension for the auxiliary wheel/e can be provided by various means.

A spring can be used of which some of the methods of use are depicted diagrammatically in Figures 6,7 and 8.

Figure 6 has been described earlier.

Figure 7 shows an enlarged view of the handle from Figure 4. Figure 7 shows where a spring G has been positioned between the vertical part of the ULNA shaped member M and a member of the trolley/device F. Another way of using a spring tension device is shown in Figure 8. In this case the spring G is placed between the pivoted arm P and a member of the trolley/device F. The link (bar or cable) to operate the auxiliary wheel in Figure 8 has been omitted for clarity. The retraction tension for the auxiliary wheel/e can also be provided by gravity of which one type is depicted in Figure 9.

Figure 9 shows a scheme where the auxiliary wheel/e is positioned near the front support wheels of a trolley/device and where the operator/user of the trolley/device pushes the trolley/device from a position near the rear support wheels. The pivoted amm P is extended toward the operator/users end of the trolley/device and the weight of the pivoted amn is adjusted by design to ensure that the moment force at end E is higher than that of the opposite end thus keeping the wheel retracted. To operate this device a lever or handle could be attached to end E of the pivoted arm P by a suitable connection.

The retraction tension could also be provided by the weight of the trolley/device itself.

Figure 10 depicts a scheme where this can be done such that a support wheel A and auxiliary wheel B are mounted on a common plate which is fixed to a chassis member via a hinge H. The auxiliary wheel/e can be deployed by any method - a cable method is shown in the figure where K is the sheathed cable with inner cable C. When the lever/cable is released after deploying the auxiliary wheel the auxiliary wheel, B retracts due to the relative placing of the support wheel A and the hinge.

The weight of the trolley/device acting on the support wheel A provides the force to retract the auxiliary wheel/s.

- 3 The retraction/deployment of the auxiliary wheel/e could also be provided directly by movement of the lever without any tension spring e.g. pulling the lever back retracts the auxiliary wheel/e and pushing the lever forward deploys the auxiliary wheelts. The lever could also have a means of locking it in either the retracted or deployed position. With all the schemes depicted they can be made to operate in the opposite sense such that the auxiliary wheel/e are normally deployed and the operator controls the auxiliary wheel/e by retracting it/them from the ground surface.

The auxiliary wheel/e could be of traditional type or be specially selected to have a high friction surface to aid their operation when in contact with the surface.

Additionally they could be Wide to resemble a roller to further enhance friction with the surface.

The auxiliary wheel/e could be totally fixed about an essentially vertical axis as previously described or they could be steerable to specifically control the direction of the trolley/device when they are deployed. Also the trolley/device could have fixed support wheels and castor type auxiliary wheel/s.

The auxiliary wheel/e when deployed do not necessarily need to take the whole weight of the trolley/device. By just kissing the ground surface the auxiliary wheells will still control the direction of the trolley/device. The auxiliary wheel/e however can be allowed to support weight of the trolley and take load off the support wheel/s.

This invention could also be used where the auxiliary wheel/e are fixed and are normally deployed to control the directional movement of the trolley/device and where the auxiliary wheel/e are retracted by the operator to allow the trolley/device to ride on the supporting wheels which if of castor type would allow random movement of the trolley/device.

The device could have fixed, steerable or castor type support wheels. The auxiliary wheel/e however would be of different type. The foregoing generally describes a device with castor type support wheels and fixed (or steerable) type auxiliary wheel/s.

However the device could have fixed (or steerable) support wheels where the direction is normally controlled and where deployment of castor type auxiliary wheel/e allows free movement.

Figure Legend: A = Castor Wheel B = Auxiliary Wheel C = Inner Cable D = Direction D E=EndE F = Fixed Member G = Spring H = Handle J = Guide K = Sheathed Cable

L = ELI shape M = L. shaped member N = Direction N P = Pivoted Bar R=Bar S = Attached Arm T = Pivot V = Lever

Claims

DIRECTION CONTROL FOR WHEEL SUPPORTED DEVICES / TROLLEYS

A9DICatiOn NO GB 0215541.4 CLAIMS 1 - 22 Page 1 of 3

Claim 1 A device having supporting wheels or castors which contact with a surface and where the device has at least one auxiliary wheel which can repeatedly be deposKed to contact the surface and released as needed to control the direction of the device.

Claim 2 A device having supporting wheels or castors which contact with a surface and where the device has at least one auxiliary normally retracted wheel which can be deposited to contact the surface and released as needed to control the direction of the device.

Claim 3 A device working in opposHe sense to claim 2 having supporting wheels or castors which contact with a surface and where the device has at least one auxiliary wheel normally deployed to contact a surface which can be retracted as needed to control the direction of the device.

Claim 4 A device as described in claims 1, 2 and 3 with more than one auxiliary wheel.

Claim 5 A device where the deposition / retraction of an auxiliary wheel/e on to a surface is controlled by an operator of the device.

Claim 6 A device as described in claims 1 to 5 where the direction of the auxiliary wheel/e is controlled by fixing the auxiliary wheel/e in a particular direction by preventing any rotation about an essentially vertical axis.

Claim 7 A device as described in claims 1 to 5 where the direction of the auxiliary wheel/e is controlled about its essentially vertical axis to act as a steering device.

Claim 8 A device as described in claims 1 to 5 where the direction of the auxiliary wheel/e is allowed to rotate freely about an essentially vertical axis as in the case of a castor.

DIRECTION CONTROL FOR WHEEL SUPPORTED DEVICES / TROLLEYS

AnDIication No GB 021 5541.4 CLAIMS 1 - 22 Page 2 of 3 Claim 9 A device as described in claim 5 where the deposition of the normally retracted auxiliary wheel/e on to a surface is controlled by an operator of the device and being essentially automatic by way of the lever used to operate the auxiliary wheel/e is also the handle used to move the device. The handle/lever being allowed to move relative to the device and with suitable linkage operates deposition of the auxiliary wheel/e - releasing the handle automatically allows the handle to return to its original position and similarly retraction of the auxiliary wheel/e occurs.

And similarly in opposKe sense where the handle is used to retract a nominally deployed wheel.

Claim 10 A device as described in claim 5 where the deposition of the auxiliary wheel/e on to a surface is controlled by an operator of the device and where a lever is used to fix the position of the auxiliary wheel/e in the retracted or deposKed position.

Claim 1 1 A device as described in claim 5 where the deposition of the normally retracted auxiliary wheells on to a surface is controlled by an operator of the device and where the lever used is continuously held to depose the auxiliary wheel/s. I<eleasing the lever automatically allows the lever to return to as original position and accordingly retraction of the auxiliary wheel/e occurs.

And similarly in opposite sense where the lever is used to retract a normally deployed wheel.

Claim 12 A device as described in previous claims where the normally retracted auxiliary wheells in its normal retracted position is held retracted by a tension device e.g. a spring or bungee elastic And similarly in opposite sense for normally deployed auxiliary wheel.

Claim 13 A device as described in previous claims where the nominally retracted auxiliary wheel/e in its normal retracted position is held retracted by a counter balance such as gravKy reacting across a fulcrum.

And similarly in opposKe sense for a normally deployed auxiliary wheel.

Claim 14 A device as described in previous claims where the nominally retracted auxiliary wheol/s in Ks normal retracted position is held retracted by manual operation e.g. by an attached lever.

And similarly in opposite sense for a normally deployed auxiliary wheel.

DIRECTION CONTROL FOR \\fHEEL SUPPORTED DEVICES / TROLLEYS ADDIication No GB 0215541.4 CLAIMS 1 - 22 Page 3 of 3 Claim 15 A device as described in previous claims where the normally retracted auxiliary wheel/e in its normal retracted position is held retracted by pressure transmitted via one of the support wheels e.g. where the support wheel and auxiliary wheel are mounted on a common member.

And similarly in opposite sense for a normally deployed auxiliary wheel.

Claim 16 A device as described in previous claims where the auxiliary wheel/e is of a traditional wheel pattem.

Claim 17 A device as described in previous claims where the auxiliary wheel/e is designed like a roller to provide a larger contact area with the surface.

Claim 18 A device as described in previous claims where the device uses fixed, steerable or castor supporting wheels.

Claim 19 A device as described in previous claims where the auxiliary wheel/e is fixed, steerable or castor.

Claim 20 A device as described in previous claims where the auxiliary wheelIs when deposited just kisses the surface such that the supporting wheels still support the device.

Claim 21 A device as described in previous claims where the auxiliary wheel/e when deposited supports the device by effectively transferring load from a supporting wheel/e to the auxiliary wheel/s.

Claim 22 A device as described in previous claims where the auxiliary wheel/e are placed adjacent, or remote, infront, behind, or beside a support wheel.