GB2061208A - Vehicle turntable - Google Patents

Abstract

A vehicle turntable has a pair of spaced-apart wheel-supporting track members 10, 11 fixed by a spider mounted about and rigidly connected to a centrally located friction-reducing bearing which is mounted upright within a pit, each track member being marginally above ground and having lockably upstandable wheel-stops near each track member end, each wheel- stop being stowable substantially flush with its associated surface when individually tripped, whereby a vehicle driven forward onto said track members traverses a stowed pair of said wheel-stops respectively pre-tripped at the approach ends of said track members, and then clears the upper extremity of said bearing during transit along said track members before the front wheels of said vehicle engage and are halted by the remaining upstanding pair of wheel-stops. <IMAGE>

Description

SPECIFICATION Vehicle turntable This invention relates to turntables of the kind adapted to support and re-orient vehicles which may be brought to a halt thereon, and more particularly to a simpler and more economical form of such apparatus than hitherto available.

It is known to construct turntables of the kind wherein a substantially circular platform is rotatable within a recess of similar shape in a road or floor surface, whereby the top of the platform is flush with that surface and rotatable with respect thereto, and whereby a vehicle which is driven onto said platform from a given direction, and brought to resttemporarily upon the platform, may be driven off in a different direction, most commonly the reverse direction, after a suitable rotation of said platform.

It has been found, however, that prior known arrangments of the above-mentioned kind have suffered from certain disadvantages. For example, the cost of construction is usually high, because the platform must be sufficiently rugged to withstand the load of any vehicle likely to be driven onto it (which usually means any vehicle which will fit) and also because the rotary drive means is commonly a ring-gear fixed near the periphery of the platform and adapted to be engaged by a pinion drivable by a motor or the like.

Furthermore, conventional turntables have an undesirable tendency to tip up at the rear edge when a vehicle runs onto the forward edge, and/or tip at the forward edge when a vehicle runs off the rear edge. In addition, difficulty is often experienced in halting a vehicle substantially centrally upon such turntables, or even within the peripheral limits, because the position of the vehicle's wheels is invariably impossible to view directly, and very difficult to judge indirectly, owing to the enveloping bodywork and/or low driving seat position dictated by current fashions in automotive body styling.

It is an object of the present invention to overcome the above and other disadvantages.

According to the invention therefore, in one of its aspects, a turntable adapted to support a vehicle comprises, in combination, a pair of spaced-apart wheel-supporting track members fixed rigidly in mutual relationship by a spider which is in turn mounted about and rigidly connected to a centrally located friction-reducing bearing which is mounted upright within a pit in a floor or ground tarmac, each said track member being marginally elevated above the level of said tarmac and having wheel-stop means temporarily and lockably upstanding near the outer upper surface of each respective end of said track member, but each said wheel-stop means being stowable substantially flush with its associated surface when demounted by individual trip means, whereby a vehicle driven forward onto said track members from the adjacent tarmac level traverses a stowed pair of said wheel-stop means respectively pre-tripped at the approach ends of said track members, and then clears the upper extremity of said bearing during transit along said track members before the front wheels of said vehicle engage and are halted by the remaining pair of said wheelstop means pre-locked into an upstanding format near the respective exit ends of said track members.

One embodiment of the invention defined in the preceding paragraph will now be described herein with reference to the accompanying drawings, in which similar references indicate corresponding parts, and in which: Figure 1 shows a turntable in plan view, Figure 2 shows in side elevation, and partly in section, the apparatus of Figure 1, Figure 3 shows, in side elevation, a section along the line Ill-Ill of Figure 1, and Figure 4 shows schematically, in plan view, the apparatus of Figure 1 installed on a typical, crowded site.

Upon referring to the drawings it will be seen that a bearing 5 may be a ball-bearing or roller-bearing suitably mounted upon an upright spindle 6, the lower end of which is fixed via a flange 7 to a sole-plate 8 at the bottom of the pit 9.

The track members 10,11, which may be composed of any solid material such as mild steel or aluminium, may each be of the order of 12 feet in length and 18 inches in width, with their inner sides approximately 4 feet apart. Some cross-bracings, for example 12,13,14 and 15, of simple angle section and constructed of similar material, extend between the track members 10 and 11, and serve to support a plurality of hard rubber wheels, 16,17,18,19,20,21,22 and 23, of the nevertheless resilient kind commonly used on boat-trailers to support a hull without damage thereto.Said wheels have an external rubber tyre bonded to an internal sheath of metal, which is journalled via plain or roller bearings or other friction reducing means to suitable axles, mounted upon casters such as 24,25,26 and 27 which are in turn attached respectively to said bracing members 12,13 14 and 15. The turntable is thus supported with great stability by said wheels without scrubbing thereof during rotation of said turntable about the spindle 6, provided that the surface ofthe ground or floor of the pit 9 is composed of some suitable hard load-bearing tarmac material into which the wheels do not sink, especially when the turntable is supporting a vehicle.

Ordinarily, said wheels each have a carrying capacity of approximately three tons and hence a car such as 28 of medium dimensions, weighing some 1- tons and thus imposing a load of approximately 0.4 tons upon each of its own tyres, is readily supported. It is merely necessary to proliferate the number of turntable wheels, having due regard to their footprint size in comparison with the car tyres, to ensure that they apply a pressure upon the tarmac of the same order as that imposed by the car itself.

Said wheel-stop means may comprise in each case a simple hinged flap such as 29 and 30 as shown in Figure 2, located in or near the upper surface near the end of each said track member such as 10, the flap being held in the upright position as shown to the right of Figure 2 by means of a peg or the like upon a link 31, which is hinged to track member 10, and which engages removably a simple detent in flap 30. The peg may be adapted for removal either by a hand operation, tor by means of a pedal, not shown) so that the user thereof may easily disengage it, as shown to the left of Figure 2 where the link 32 has been dropped to allow flap 29 to lie flat.If desired, a fixed or removable auxiliary ramp such as 33 composed of suitable rigid solid material such as wood may be located at or across each end of each track member, or alternatively across the entire width of seven feet or so of the turntable end. Such a ramp or ramps may serve to raise the vehicle wheels smoothly from tarmac level to the surface level of said track members through a distance of approximately 5 inches. If desired, also, suitable guard rails (not shown) may be located at a similar height along the respective outer edges of said track members. The height of the upper surface of the respective track members should be such that at least a clearance of 5 inches or so is provided between the lowermost part of the vehicle chassis and the uppermost extremity of the beam member 34, including its attachments to the central spindle 6.

This beam member is fastened in turn by any suitable means to additional bracing members 35 and 36, the outer ends of which are fastened to the track members 10 and 11 to constitute a spider or torque frame. All the bracing members described herein are, of course, located upon the underside of the track members 10 and 11, to ensure an unobtructed wheelway upon the upper surfaces of said track members.

The remaining dimensions of the system are dictated by the probable track and overall length of a vehicle likely to use the turntable. Thus, although the overall width of the turntable to the outer extremities ofthe members is some 18 inches greater than the track of a vehicle, a further space amounting to approximately a total of 20 feet must be left clear of obstructions, trees or the like, to permit the loaded turntable to rotate as shown in Figure 4. That is to say, the space of twenty feet or so normally provided forthe length of a vehicle in a carport, garage or the like, is also left to provide a clearance width for the apparatus.Nevertheless, it is merely necessary to provide a driveway such as 37 up to the access side 38 of the pin 9, having a width approximately 2 feet greaterthan that of the vehicle itself. It will be appreciated, of course, that no such driveway need be provided beyond the pit on the side 39. Thus, a very narrow driveway will suffice provided that a vehicle driven therealong has adequate clearance and visibility when driven forward, since it is merely necessary to rotate it upon said turntable until the exit region thereof registers with said narrow driveway along with the vehicle may then be driven forwards with ease in the opposite direction.This is, of course, not only a great aid to safety, since the presence of obstructions or persons on or close to the driveway may be observed with ease, but the design and construction of buildings such as 40 upon narrow parcels of land as shown in Figure 4 may be carried out with due regard to the fact that only very narrow driveways are necessary if vehicles are to be parked at the rear of such buildings, since it is merely necessary to provide access, behind such buildings, to an area approximately 20 feet by 20 feet which does not necessarily need to be aligned at right angles to the narrow driveway 37, but may be inclined at an angle thereto as shown.

In use, apparatus constructed in accordance with the invention would have its wheel-stop means on the approach side normally demounted and stowed, whilst those at the exit side would be upright and locked in a position in which the user last left the apparatus. Then upon an approach thereto by a vehicle in known manner the latter is driven onto the track members in approximate alignment and brought slowly to a standstill with the front wheels resting against said upright wheel stops.Upon then rotating the turntable by simply leaning against one or other end of the vehicle, the turntable may be rotated upon its support wheels through 180 until its exit end is aligned with said driveway, whereupon a simple reversal of the attitudes of said wheel-stop means by the operation of the above-mentioned hinged links permits the vehicle to be driven off the turntable forwards in a normal manner. Meanwhile, of course, said wheel-stop means are left in the position suitable for reception of the next vehicle (or indeed of the same vehicle) which may require use of the turntable.

It will be seen that the invention provides a simple and economical arrangement which may be constructed partly from simple stampings or other uncomplicated structural members and partly from stock items such as the rubber support wheels and bearing. Furthermore, it is silent in operation owing to the fact that all motion takes place via said bearing and by the rolling action of the rubber wheels on the pit tarmac. In addition, no powered operating means, such as electric motors or the like, need be employed and the necessity for such expensive items as an external ring gear is avoided. Finally, the tarmac area need be of no better quality than that of the driveway itself, and owing to the manner in which the rubber support wheels co-act with the centrally located bearing the turntable does not tend to tilt undesirably when a vehicle enters or leaves said track members.

If desired, the track members 10 and 11 may be provided with some kind ofvernieradjustment whereby they may be moved backwards or forward marginally with respect to the spindle 6 so as to move an entire vehicle, such as a caravan standing on the turntable, to the extent necessary to hitch it up to another vehicle (not on said turntable).

Furthermore the turntable, although described herein with reference to the parking of vehicles, may also be used in factories, workshops, supermarkets, vehicle repair centres or the like, so that any article or workpiece mounted thereon may be turned to obviate the need for movement of tradesmen's power tools broughtto bear on such an article or workpiece.

Claims (6)

1. A turntable adapted to support a vehicle comprising, in combination, a pair of spaced-apart wheel-supporting track members fixed rigidly in mutual relationship by a spider which is in turn mounted about and rigidly connected to a centrally located friction-reducing bearing which is mounted upright within a pit in a floor or ground tarmac, each said track member being marginally elevated above the level of said tarmac and having wheel-stop means temporarily and lockably upstanding nearthe outer upper surface of each respective end of said track member, but each said wheel-stop means being stowable substantially flush with its associated surface when demounted by individual trip means, whereby a vehicle driven forward onto said track members from the adjacent tarmac level traverses a stowed pair of said wheel-stop means respectively pre-tripped at the approach ends of said track members, and then clears the upper extremity of said bearing during transit along said track members before the front wheels of said vehicle engage and are halted by the remaining pair of said wheel-stop means pre-locked into an upstanding format near the respective exit ends of said track members.

2. A turntable as claimed in claim 1, wherein a plurality of support wheels is journalled with respect to mountings beneath said turntable and adapted to roll upon the floor of said pit during rotation of said turntable about said centrally located bearing.

3. A turntable as claimed in claim 2, wherein said mountings are castors adapted to permit said support means to roll without scrubbing.

4. A turntable as claimed in any one of claims 1 to 3, wherein a ramp is located at each end of each said track member in conjunction therewith, and has a slope which extends from said tarmac level to the height of said upper surface of said track members.

5. A turntable as claimed in claim 4, wherein each said ramp is detached from, or detachable from, its associated track member or track members.

6. A turntable substantially as described herein with reference to the accompanying drawings.