GB2315473A - A vehicle turntable - Google Patents

Abstract

A vehicle turntable has a base 25 adapted to be laid on the ground and defines a circular track 29. A turntable platform 12 has on its underside a circular track 38 corresponding to that of the base, a plurality of rotatable elements 31 being disposed between the base and platform tracks 29 and 38. An electric motor 20 is mounted on the platform to effect rotation thereof and includes a connection cable for the supply of power from the battery of a vehicle on the platform.

Description

TURNTABLE This invention relates to a vehicle turntable adapted to allow a vehicle to be turned round within a relatively confined space, such as on a private driveway for a domestic dwelling.

There have in the past been many proposals for vehicle turntables wherein a vehicle may be driven on to a platform which is then rotated about a vertical axis through 1800 so that the vehicle faces in the opposite direction. The vehicle may then be driven off the turntable. Though such vehicle turntables may be intended for installation on a private driveway, they are relatively expensive to install, in view of the groundworks necessary to accommodate the supporting arrangement for the platform and the operating mechanisms therefor. Thus, though the use of such a turntable may be highly desirable for example if the private driveway leads off a busy main road, turntables are rarely installed.

Some of the known proposals for vehicle turntables include no platform power drive arrangement. Such a turntable must be pushed round manually following the parking of a vehicle on the platform. As this may require some considerable effort, manual turntables are not at all popular and instead turntables more frequently use a mains powered electric motor to effect the rotation of the platform. This greatly increases the cost of the installation since a chamber must be excavated in order to accommodate the motor, electrical control gear and drive arrangement and special precautions have to be taken for the safe installation of the mains supply, in a below-ground external situation.

It is a principal aim of one aspect of the present invention to provide a vehicle turntable which may be installed in a confined space without the need to perform extensive groundworks. It is a further aim of this invention, either separately or in combination with the first aim, to provide a turntable which is easy to operate and yet is relatively cheap to manufacture.

According to one aspect of the present invention, there is provided a vehicle turntable comprising a base adapted to be laid on the ground which base defines a circular track, a plurality of rotatable elements disposed on the track, a platform adapted to support a vehicle to be turned and having on its underside a circular track corresponding to that of the base, the platform track resting on the rotatable members so that the platform is rotatably supported thereby, an electric motor mounted on and arranged to effect rotation of the turntable, and connection means including an elongate cable and adapted to allow the electric motor to be supplied with electric power from the battery of a vehicle on the platform.

According to a second aspect of this invention, there is provided a vehicle turntable comprising a base adapted to be laid on the ground which base defines a circular lower track of open-topped channel-shaped cross-section, a plurality of rotatable elements disposed in the channel-shaped lower track for rolling therearound, a platform adapted to support a vehicle to be turned and having on its underside a circular upper track of the same effective diameter as that of the lower track with the upper track bearing on the rotatable elements, and a central rotatable connection concentric with the upper and lower tracks, connecting the platform to the base whereby the base may be laid directly on the ground surface with the platform rotatable about the vertical axis of the rotatable connection.

The turntable of this invention is intended for installation in a location where the turntable will be used relatively lightly, such as on a private driveway to turn round a private car. The turntable is configured to allow easy installation without the need to perform any significant groundworks and for most circumstances there will be no need to do much more than drill two holes into the ground respectively to accommodate a central pin at the rotatable connection between the platform and the base and to accommodate a second pin disposed at a location spaced radially from the central pin and which serves to prevent rotation of the base.

In view of the mechanism whereby the platform is supported on the base, it is possible for the height of the upper surface of the platform above the lower part of the base to be relatively small and typically no more than about 50mm. This may be achieved quite easily using rotatable elements in the form of 25mm steel balls located in the channel of the lower track and with the upper track of the platform in the form of a circular metal strip which bears on the balls.

In a preferred embodiment of turntable using the first aspect of the present invention, the motor for effecting rotation of the turntable is provided on the platform itself. That motor preferably is drivingly coupled to a ground-engaging wheel whereby powering of the motor rotates the wheel which then rotates the turntable. In this way, no excavations are required to accommodate a stationary motor which drives the rotatable platform. However, the problem of the provision of a rotatable electrical connection to supply power to a motor on the platform is overcome by powering the motor from the battery of a motor vehicle on the platform.

The ground-engaging wheel may take the form of a rubber-tyred wheel arranged to drive directly on the surface of the ground, for example if the turntable is installed on a tarmacadam driveway. However if the ground surface is not suitable for direct driving, the base may include a further track along which the wheel runs. In this case, the further track could be a toothed rack, the ground-engaging wheel then having a correspondingly toothed periphery so as to provide positive drive.

Preferably, means are provided to lift the groundengaging wheel clear of the ground. When engaged and the motor is not powered, the wheel may serve as a brake for the turntable, resisting rotation thereof, but when the wheel is lifted clear, the turntable may be rotated manually either with or without a vehicle on the platform.

In a preferred embodiment the platform is generally circular and is provided with two connection means for the motor, at diametrically opposed locations on the platform periphery. In this way, the driver may have easy access to a cable and a connector for the vehicle battery, irrespective of the side of the platform from which the vehicle gained access to the platform. For example, if the turntable is used exclusively to rotate a vehicle through 1800 in a private driveway, the vehicle will be driven on to the platform at alternate sides, each time the turntable is used. The connector may comprise a plug to fit the cigarette lighter socket of the vehicle, and in this case there may be no need to provide any other switchgear, the motor being turned on and off by the plugging or unplugging action.

Depending upon the load which the platform is to carry and the materials from which the platform and base are made, it may be advantageous to provide more than one circular lower track and corresponding upper tracks on the platform. Typically two such tracks may be provided, though up to six could be employed for some applications.

As the turntable of this invention is very easy to install and requires no groundworks, it is envisaged that the turntable may be supplied with the base and the platform in four separate pieces each of quadrantshape and ready to be joined together using for example nuts and bolts. In this way, the parts of the turntable may be readily portable and so the complete assembly lends itself to selling in builders' merchants, do-it-yourself stores and so on.

By way of example only, one specific embodiment of vehicle turntable of the present invention will now be described in detail, reference being made to the accompanying drawings in which: Figure 1 is a general perspective view of a complete turntable installed on the ground; Figure 2 is a plan view of one quadrant of the base of the turntable; Figure 3 is an underplan view of one quadrant of the platform; Figure 4 is a edge view on the quadrant of Figure 3; and Figure 5 is a detailed sectional view on an enlarged scale of the drive arrangement for the platform.

Referring initially to Figure 1, there is shown an embodiment of vehicle turntable of this invention, as installed on the surface of a tarmacadam drive. The turntable comprises a circular platform 10 assembled from four quadrants 11 to 14, bolted together as shown at 15 in a manner which will be described in more detail below. The platform 10 has a peripheral skirt 16 but depending upon the height of the upper surface of the platform above the ground, that skirt may be angled as shown in broken lines in Figure 5, at 17. As the upper surface of the platform should be no more than 50mm above the ground surface, but may be as little as 35mm to 40mm above the ground surface, it is envisaged that there should be no need to provide an angled skirt and that a vehicle may simply be driven over the relatively small step in order to gain access to the upper surface of the platform.

At two diametrically opposed locations there are provided columns 18 upstanding from the periphery of the platform, each column carrying a pair of cleats (not shown) around which is wound an electric cable 19 having a cigarette lighter plug at the free end. Each column includes a waterproof socket for the respective cigarette lighter plug in order that the plug may be safely stowed in that socket, when not in use.

Adjacent one column 18 is a motor unit 20, which will be described in further detail below. A lever 21 upstands from the motor unit and is arranged to raise or lower a drive wheel.

Figure 2 is a plan view on a quadrant of the base of the turntable. This base quadrant comprises a principal radial arm 25 projecting from a hub 26 and two side radial arms 27 disposed at 900 to each other.

Welded to these arms 25 and 27 is an inner lower track 28, an outer lower track 29 and a drive track 30. The tracks 28 and 29 are of channel-section and located in each of those tracks is a plurality of balls 31, held spaced apart by respective spacers 32. For the sake of clarity, only three balls 31 and two spacers 32 are shown, in each track.

Adjacent the ends of the tracks 28 and 29 are coupling blocks 33, welded to the respective side arms 27. Using these blocks, four quadrants may be joined together to form a complete circular base, though it will be appreciated that the other three quadrants do not have a central hub 26. Rather, the principal radial arm 25 of each of the other quadrants is provided with a hole by means of which that arm may be bolted to the hub 26 of the described quadrant, and the inner ends of the side radial arms are welded directly to the arm 25.

The hub 26 has a central pin (not shown) which extends vertically downwardly, to be received in a hole formed in the ground when the base is installed. A further pin 34 is provided on the principal arm 25 of the illustrated quadrant, which pin also extends vertically downwardly, to be received in a corresponding hole formed in the ground, so as thus to prevent rotation of the base about the central pin.

Figures 3 and 4 show a quadrant of the platform.

This is fabricated from a quadrant-shaped sheet 36 of decking having a non-slip upper surface. Skirt 16 is welded to the outer periphery of that sheet 36 and two arcuate tracks 37 and 38 are also welded to the underside of sheet 36, at positions corresponding to the tracks 28 and 29. Along one radial edge of the sheet 36, there are welded two attachment plates 39 to extend below but parallel to sheet 36. These plates are provided with holes 40, by means of which the quadrant may be attached to a like quadrant, with bolts extending through holes 40 and also holes 41 along a radial edge of the adjacent section.

As with the base, the illustrated quadrant is welded to a hub 42 but the other three quadrants have no such hub. Instead, the corresponding central part of each other quadrant is formed with a hole, by means of which those quadrants may be bolted to the hub 42 of the illustrated quadrant. The hub 42 includes a stub shaft 43 which is received in a bearing 44 in hub 26 of the base quadrant shown in Figure 2.

Using 25mm balls in the channel-shaped tracks 28 and 29, a most compact assembly in the vertical direction may be constructed, having the upper surface of the platform typically 35mm to 40mm above the ground surface. The platform is securely located by the central connection between the two hubs, and by having at least two separate concentric tracks, the platform may have a sufficient load-bearing capacity without deforming significantly when supporting a private car.

Referring now to Figure 5, there is shown a detail view on the motor assembly 20. A 12v DC motor 45 is mounted on the platform periphery and is drivingly coupled to a rubber-tyred wheel 46 by means of a drive belt 47. The wheel is carried on a stirrup 48 urged downwardly by a spring 49 to engage track 30 of the base. Lever 21 is coupled to the stirrup 48 so that movement of the lever from the position illustrated in Figures 1 and 5 to a horizontal position lifts the wheel 46 a few mm, against the action of spring 49, clear of the track 30.

When the wheel 46 engages track 30 and motor 45 is not powered, the wheel will serve to restrain easy rotation of the platform. The motor may be powered by removing one of the plugs from its socket in a column 18, uncoiling the cable and then inserting the plug into the cigarette lighter socket of a car parked on the platform. When the platform has rotated through the required angle - and usually 1800 - the plug may be removed, the cable recoiled and the plug inserted into the holder of the column 18. Next time a vehicle is driven on to the turntable, the driver's side will be adjacent the other column 18 and the driver may use the other cable and plug, to effect rotation of the platform.

In the event that the turntable is to be rotated manually, either with or without a vehicle on the platform, the wheel 46 may be raised clear of track 30 by means of lever 21, whereafter pressure may be applied in the circumferential direction for example to a column 18.

In the above-described embodiment, the groundengaging wheel 46 is shown running on drive track 30 external of the outer lower track 29. There may be advantages in interchanging the radial positions of the drive track 30 and the outer lower track 29 so that the latter surrounds the drive track 30. This may allow a more compact construction and also give better support to the periphery of the platform.

Claims (17)

1. A vehicle turntable comprising a base adapted to be laid on the ground which base defines a circular track, a plurality of rotatable elements disposed on the track, a platform adapted to support a vehicle to be turned and having on its underside a circular track corresponding to that of the base, the platform track resting on the rotatable members so that the platform is rotatably supported thereby, an electric motor mounted on and arranged to effect rotation of the turntable, and connection means including an elongate cable and adapted to allow the electric motor to be supplied with electric power from the battery of a vehicle on the platform.

2. A vehicle turntable as claimed in claim 1, wherein the motor is drivingly coupled to a groundengaging wheel, whereby powering of the motor rotates the platform.

3. A vehicle turntable as claimed in claim 2, wherein the ground-engaging wheel runs on a track surface provided on the base.

4. A vehicle turntable as claimed in claim 2 or claim 3, wherein the ground wheel is spring-urged downwardly and is provided with means permitting the wheel to be raised against the action of the spring.

5. A vehicle turntable as claimed in any of claims 2 to 4, wherein the motor is provided on or adjacent the outer edge of the platform.

6. A vehicle turntable as claimed in any of the preceding claims, wherein the platform is generally circular and is provided with two connection means for the motor, at diametrically-opposed locations of the turntable.

7. A vehicle turntable as claimed in any of the preceding claims, wherein the connection means includes a second elongate cable also adapted to allow the electric motor to be supplied with electric power from the battery of a vehicle on the platform.

8. A vehicle turntable as claimed in claim 7, wherein the second elongate cable is provided at a location on the platform substantially diametrically opposed to the location of the first-mentioned cable.

9. A vehicle turntable as claimed in claim 7 or claim 8, wherein each of the electric cables are provided on a respective column mounted at or adjacent the platform periphery, at opposed locations.

10. A vehicle turntable as claimed in any of the preceding claims, wherein the (or each) electric cable is provided with a plug adapted for connection to the cigarette lighter socket of a vehicle.

11. A vehicle turntable comprising a base adapted to be laid on the ground which base defines a circular lower track of open-topped channel-shaped crosssection, a plurality of rotatable elements disposed within the channel-shaped lower track for rolling therearound, a platform adapted to support a vehicle to be turned and having on its underside a circular upper track of the same effective diameter as that of the lower track with the upper track bearing on the rotatable elements, and a central rotatable connection concentric with the upper and lower tracks, connecting the platform to the base whereby the base may be laid directly on the ground surface with the platform rotatable about the vertical axis of the rotatable connection.

12. A vehicle turntable as claimed in claim 11, and also as claimed in any of claims 1 to 10.

13. A vehicle turntable as claimed in any of the preceding claims, wherein each rotatable element comprises a ball.

14. A vehicle turntable as claimed in claim 13, wherein a spacer is positioned between adjacent balls in the lower track.

15. A vehicle turntable as claimed in any of the preceding claims, wherein the rotatable connection includes a vertically downwardly extending pin which is received in a hole drilled vertically into the ground.

16. A vehicle turntable as claimed in claim 15, wherein the base includes at least one pin at a location spaced from the centre of the tracks which pin projects vertically downwardly and is received in a further hole drilled vertically into the ground.

17. A vehicle turntable as claimed in claim 1 or claim 11 and substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.