GB2191758A - Elevating table - Google Patents

Abstract

An elevating worktable on which a motorcycle may be placed in order to carry out repairs at a height convenient to the operator, has a table top (1) which is supported by pairs of legs (7, 9) forming a collapsible parallelogram linkage so that the table top may rise and fail in an arc. Primary cams (12) and secondary cams (15) are employed to effect the lift, these cams being turned by manual effort on handles (12a, 15a) attached to the cams. The cam followers are mounted on a cross-member (17) and on spindles (20) carried by brackets (21) respectively. <IMAGE>

Description

SPECIFICATION Elevating table This invention relates to an elevating table.

Motorcycle repair workshops are frequently equipped with elevating work tables, by which the motorcycle may be raised to a height which is convenientforthe operator, when attending to the engine orother low parts ofthe motorcycle. Inthe trade, the tables used are often raised by hydraulic rams or screw jacks. Such elevating tables are relatively expensive, and for a rider who wishes to carry out infrequent repairs to his motorcycle, a hand operated elevating table may be used.

An important alternative use concerns the lifting of wheelchairs into vehicles. Some vehicles have been adapted for the loading of invalids in wheelchairs, by the addition of a permanently fitted elevating table.

With this invention such a table would not be necessary as a permanent fitting, as the elevating table here described could be used with any vehicle.

In addition to the two uses outlined above, the elevating table may be used to lift goods of any description. The top surface may comprise a conveyor in some applications.

According to the present invention there is provided an elevating table comprising a base, a tabletop parallel with the baseand parallel support means articulated with and interconnecting the base and the table top to form a collapsible parallelogram linkage, and a manually operable lifting arrangement for the table top and mounted between the base and thetabletop,the arrangement comprising cam means, cam follower means cooperablewith the cam means, and a lever angularly movable to cause relative movement between the cam means and the cam follower means.

A specific embodiment of the invention will now be described, by way of example, with reference to the accompanying drawings, in which Figure 1shows, in side elevation, the table top in the raised position; Figure2 shows, in plan view, the table top in the raised position.The table top has been cut away to show items therebelow; Figure 3 shows, in end elevation, the table in the raised position; Figure4shows, in fragmentarysection andto an enlarged scale, the camshafts, cams, and table top assembly; and Figures 5, 6and 7 illustrate the lifting procedure, all in side elevation; Figure Sshowing the table fully lowered, with a motorcycle mounted, the motorcycle being shown in chain dotted lines; Figure 6showing the table at an intermediate height, when the primary cam has been utilised; and Figure 7showing the table atthe full height, when the secondary cams have been utilised.

Referring now to Figures 1,2,3 and 4,thetabletop 1 may incorporate a detachable portion 1 a to facilitate removal of the back wheel of the motorcycle. The top 1 is carried on two side members 2 which are drilled to carry a crossrod 3 towards one end, and the side members 2 also house bearings 4shown in Figure 4. A base frame 5 carries crossrod 6. A pair of legs 7 are pivotally mounted at each end around crossrods 3 and 6. The base frame 5 carries a crossrod 8. A pair of legs 9 are pivotally mounted around crossrod 8 at the base, and via bearings 10 around a primary camshaft 11 which is carried in bearings 4 in the side members 2. The legs are strengthened by crossbracing 7a and 9a respectively. Two primary cams 12 are secured to the primary camshaft 11, and a handle 1 2a extends from one cam.A secondary camshaft 13 passesthrough the primary camshaft 11, being rotatably mounted on bearings 14. Two secondary cams 15 are secured to the secondary camshaft 13 and a handle 1 5a extends from one cam.

Two primary cam followers 16 are rotatably mounted on crossrod 17 which may be supported by a frame crossmember 18. Two secondary cam followers 19 are rotatably mounted on spindles 20 which are carried by brackets 21 which form part of the base frame 5. Aframe crossmember 22 may be fixed to the frame5 to add supportto the crossrod 8.

Thesecondarycam handlel5amaybesecuredto frame5 by a fastener 23,thus preventing further movement of the table top.

Figures 5,6 and 7 illustrate the sequence of operations in lifting thetabletop, all being side elevations.

Figure 5 shows the table in the lowest position.

The two top side members 2 are resting on crossmembers of the base frame 5. The primary cams 12 are very close to the cam followers which are mounted on the crossrod 17. The primary cam handle 12a lies to the righthand side of the cam as shown. The secondary cams are presently inoperative,the handle 15a lying to the lefthand side of the cam in the diagrams. The motorcycle may be placed on the table top as shown, or a wheelchair may be put in a similar position. It is advantageous that the centre of gravity of the load is to the lefthand side of the camshaft, as viewed in these figures, so thatthere is an urge upwards on crossrod 3.

The handle 1 2a may be pulled anticlockwise, causing the primary cams to rotate, and causing the table to rise by the action of the primary cams against the cam followers.

Figure 6 shows this intermediate position. The secondary cams 15 may now be actuated by pulling the handle 1 5a in a clockwise direction. Contact between the secondary cams and the cam followers mounted on spindles 20 causes the table to riseto its full extent. It should be locked in this position by applying fastener 23.

Figure7 shows this position.

It is beneficial that the cams are contoured so that the rate of rise is lessened when the handles are approximately upright, this being where least power can be exerted. It is beneficial thatthere should be an indentation at the termination of each cam, so that the handles tend to remain staticwhile the operator makes the next movement.

Claims (5)

1. An elevating table comprising a base, a table top parallel with the base, and parallel support means articulated with and interconnecting the base and the tabletopto form a collapsible parallelogram linkage, and a manually operable lifting arrangementforthe table top and mounted between the base and the table top, the arrangement comprising cam means, cam follower means and lever means angulariy movable to cause relative movement between the cam means and the cam follower means.

2. Atableaccordingtoclaim 1,whereinthecam and lever means are angularly movable together.

3. Atableaccordingtoclaim 2,wherein the cam and lever means are pivoted for angular movement, atthe articulation of the tabletop and one ofthe supports, the cam follower means being mounted on the base.

4. Atable according to claim 1,2 or 3, wherein the cam means, cam follower means and the lever means comprise a primary cam, a primary cam follower and a primary lever for lifting the table top to an intermediate height, and a secondary cam, a secondary cam follower and a secondary leverfor lifting thetabletop from the intermediate heightto its fully elevated height.

5. An elevating table substantially as hereinbefore described with reference to the accompanying drawings.