GB2377416A

GB2377416A - Vehicle turntable

Info

Publication number: GB2377416A
Application number: GB0117067A
Authority: GB
Inventors: William George Lyne
Original assignee: Individual
Current assignee: Individual
Priority date: 2001-07-13
Filing date: 2001-07-13
Publication date: 2003-01-15
Also published as: GB0117067D0

Abstract

A vehicle turntable comprises a frame having two, rigidly interconnected, longitudinal members 11 each carrying a freely rotatable wheel 2 and a driven wheel 3 arranged in a diagonally opposed relationship, two combinations of an idle roller 8 and a drivable roller 6 positioned substantially across the transverse width so as to support the vehicle wheels clear of the frame, the driven wheels of the vehicle driving the drivable roller(s) and the drivable wheels such that the turntable rotates around a central pivot 15.

Description

VEHICLE TURNING MECHANISM This invention concerns a mechanism for turning a road vehicle in a limited space.

Many commercial and domestic properties have a very limited amount of land surrounding them in which road vehicles may be parked and turned. The number of vehicles which can be parked in a small area can be increased if means are provided to turn a vehicle substantially about its own vertical axis, since this reduces the need to manoeuvre the vehicle using forward and reverse gears.

Turntables are known for this purpose comprising a generally circular platform supported on a plurality of small wheels, each of which runs on a generally circular rail. The vehicle to be turned is driven on to the platform, and the platform and the vehicle standing thereon are generally turned manually, for example by applying horizontal pressure to a suitable part of the bodywork of the vehicle. Such a turning operation requires considerable physical effort, and is likely to be beyond the capabilities of an elderly, infirm or disabled person. It would be desirable to harness a source of motive power to aid the turning operation. The known turntables of the type described above also suffer from the disadvantage that they are relatively expensive to install because the platform must be countersunk into the ground so that it is substantially level with the surface of the surrounding ground, and this entails the excavation of a relatively large pit to accommodate the rail and the foundation therefor. The operation of turntables of the above type is also liable to become more difficult with time as dirt and grit accumulates on the supporting wheels and hinders their freedom of rotation.

ngly, it is an object of this invention to provide a sm for turning a road vehicle in a limited space, which sm makes use of motive power to assist a turning on and which can be installed relatively easily and sively. ention provides a mechanism for turning a road vehicle mited space which mechanism comprises a supporting omprising two longitudinal members which are rigidly ed together transversely and are spaced apart by a e such that each longitudinal member is adapted to the wheels on one of each of the two sides of a road , a pair of freely rotatable wheels which are mounted side members of the frame in diagonally opposed nship with one another, a pair of drivable wheels which nted on the side members of the frame in diagonally relationship with one another, two combinations of a e roller and an idler roller each extending tially across the full transverse width of the frame, each combination the driven roller being substantially 1 to the idler roller and spaced apart therefrom by a e such that the driven wheels of the vehicle can be ed clear of the frame by the combination of rollers, Dr transmitting rotational motion from each drivable to one of the drivable wheels and a central firmly Lvot member about which the frame can rotate. is for transmitting rotational motion from each roller to one of the drivable wheels may conveniently ibination of bevel gear wheels.

fitudinal members are preferably of channel-shaped action. The longitudinal members are also conveniently l at each end with a downwardly sloping ramp portion.

Advantageously each of the drivable rollers is supported in bearings at least one of which incorporates a ratchet mechanism such that rotational motion is transmitted to a drivable wheel when the driving wheels of the vehicle are rotating in a first sense but the drivable roller is locked to prevent rotation when the driving wheels of the vehicle are rotating in the opposite sense.

The following is a description of one embodiment of the invention, by way of example only, and is illustrated by means of the accompanying drawing in which: Figure 1 is a diagrammatic plan view of a road vehicle turning mechanism in accordance with the invention.

A road vehicle turning mechanism comprises a frame consisting of two parallel steel side members 1, each of channel-shaped cross section, rigidly connected together by means of a central transverse member 14 also of steel. The frame is provided with a pair of freely rotatable wheels 2, each mounted on a side member 1 and in diagonally opposed relationship to one another, and with a pair of drivable wheels 3 and 3'also mounted on the side members and in diagonally opposed relationship to one another. The freely rotatable wheels 2 are each mounted on bearings carried on the projecting end of a bent supporting rod 10 the opposite end of which is rigidly fixed to a side member 1. The angle of the bend in the supporting rod 10 is such that the wheels 2 rotate in planes which make an angle of approximately 45c with the side members. To the inner side of each of the drivable wheels 3 and 3'there is rigidly fixed a bevel gear wheel 4 and 4', respectively, and each combination of drivable wheel and bevel gear wheel is mounted on a bearing carried on the projecting end of a bent supporting rod 12 and 12', respectively, the opposite end of which supporting rod is rigidly fixed to a side member 1.

drivable roller 6 is mounted transversely across the n a region between the transverse centre line and one the frame, and is supported in two bearings 7 each of s rigidly fixed to the outer side wall of a channelside member 1, and each of which incorporates a ratchet sm (not shown). One end of the roller 6 is extended the outer side wall of the side member 1 and a bevel eel 5 is rigidly fixed to the extended end. The roller cated so as to engage with the bevel gear wheel 4 which ched to the wheel 3. Similarly a second drivable 6'is mounted transversely across the frame in a line s spaced apart from the line of roller 6 by a distance proximates to the length of a typical road vehicle, supported in two bearings 7'each of which is rigidly the outer side wall of a channel-shaped side member ach of which incorporates a ratchet mechanism (not One end of the roller 6'is extended beyond the outer 11 of the side member 1 and a bevel gear wheel 5'is fixed to the extended end. The roller 6'is located D engage with the bevel gear wheel 4'which is attached wheel 3'. idler roller 8 is mounted transversely across the ld is supported in two bearings 9 each of which is fixed to the outer side wall of a channel-shaped side L. The idler roller 8 is parallel to the drivable and is spaced apart therefrom by a short distance it the pair of rollers 6 and 8 together provides support for a pair of wheels of a road vehicle which ling on the turning mechanism. Similarly a second ) ller 8'supported in two bearings 9'is provided to the drivable roller 6'and in a relationship which corresponds to the raltionship of drivable with idler roller 8.

Each end of each side member 1 is provided with a downwardly sloping ramp portion 11 ro facilitate the passage of the wheels of a road vehicle on to the frame of the turning mechanism.

A central pivot point 15 is provided in the transverse member 14. The frame rotates on a bearing which is rigidly fixed to the upper end of a vertical pivot pin (not shown). The lower end of the pivot pin is firmly fixed in the ground, for example by being driven into a suitably firm subsoil layer or by being set in concrete.

In operation a road vehicle to be turned is driven under its own power on to the frame so that its driven wheel, either its front pair of wheels or its rear pair are in contact with and supported clear of the side member by one of the combinations of a drivable roller and an idler roller 6,8 or 6', 8'.

Reverse gear is selected and power is transmitted to the driven wheels of the vehicle at suitably low engine revolutions per minute. Rotational motion is thus transmitted to one of the drivable wheels 3 or 3'through one of the combinations of bevel gear wheels 4,5 or 4', 5', and the platform, with the vehicle supported thereon, is allowed to rotate until it has turned through the desired angle of rotation. Power is then disengaged from the driven wheels of the vehicle, and the vehicle is driven forward under its own power off the frame.

Claims

CLAIMS echanism for turning a road vehicle in a limited space echanism comprises a supporting frame comprising two inal members which are rigidly connected together rsely and are spaced apart by a distance such that each inal member is adapted to support the wheels on one of the two sides of a road vehicle, a pair of freely le wheels which are mounted on the side members of the diagonally opposed relationship with one another, a drivable wheels which are mounted on the side members frame in diagonally opposed relationship with one , two combinations of a drivable roller and an idler ach extending substantially across the full transverse the frame, and in each combination the driven roller bstantially parallel to the idler roller and spaced erefrom by a distance such that the driven wheels of icle can be supported clear of the frame by the tion of rollers, means for transmitting rotational from each drivable roller to one of the drivable wheels

zentral firmly fixed pivot member about which the frame te. nechanism according to claim 1, wherein the means for : ting rotational motion from each drivable roller to : he drivable wheels is a combination of bevel gear lechanism according to claim 1 or 2, wherein the linal members are of channel-shaped cross section.

Lechanism according to claim 1,2 or 3, wherein the inal members are provided at each end with a ly sloping ramp portion.

<Desc/Clms Page number 7>

5. A mechanism according to any one of claims 1 to 4, wherein each of the drivable rollers is supported in bearings at least one of which incorporates a ratchet mechanism such that rotational motion is transmitted to a drivable wheel when the driving wheels of the vehicle are rotating in a first sense but the drivable roller is locked to prevent rotation when the driving wheels of the vehicle are rotating in the opposite sense.

6. A mechanism for turning a road vehicle in a limited space as hereinbefore described with reference to the accompanying drawing.