GB2145392A

GB2145392A - Vehicle jack

Info

Publication number: GB2145392A
Application number: GB08420524A
Authority: GB
Inventors: Graham Henry Colton
Original assignee: Metallifacture Ltd
Current assignee: Metallifacture Ltd
Priority date: 1983-08-20
Filing date: 1984-08-13
Publication date: 1985-03-27
Also published as: ES281005Y; GB2145392B; DE3426402C2; GB8322490D0; DE3426402A1; ES281005U; GB8420524D0

Abstract

A jack having a support leg (11) on a rolling foot (13, 14), and a pivotally-mounted arm (20) is actuated by a screw (30) which extends between the leg and the arm and engages a nut (24) on the leg and a pivot pin on the arm. A support shoe (50) is carried on the arm and has a formation (56) for engaging a seam on a vehicle, and spaced walls (52) having apertures which receive the pivot pin. The pin has a flat face (46) and the apertures are of complementary shape. The shoe, therefore, pivots with the pin and the pin is movable by the screw during operation of the jack to control the position of the shoe and stabilise the jack. <IMAGE>

Description

SPECIFICATION Vehicle jack This invention relates to a vehicle jack of the type having a support leg provided with a foot, an arm pivoted on the leg, a load-engaging shoe on the arm, a nut on the arm or the leg, and a screw member engaged with the nut and connected between the arm and the leg for raising the arm relative to the leg.

Jacks of this type usually have an arm which projects from only one side of the leg, although it is also known to extend the arm, so that the extended arm and the leg define a scissor arrangement. The first type is disclosed in U.K. Patent Specification No. 1454847 and the second type is disclosed in U.K. Patent Specification No. 1011933.

The load-engaging shoe takes many different forms accord ing to the formation on the vehicle, which the shoe engages in use. It is common for the shoe to be provided w:th a channel member for receiving a welded flange of a vehicle body. It is also common for the shoe to be pivoted on the arm to allow angular movement of the arm relative to the shoe, as the jack is being operated with the arm moving towards the leg.

To improve stability, it has previously been proposed to control the pivoting movement. German AS No. 2621425 discloses an arrangement in which the screw and the shoe are pivoted to the arm by a common pivot pin and a very large shoe is provided, which extends along the screw and is also pivoted to the screw at another location, so that a constant angular relationship is maintained between the screw and the shoe.

The present invention provides an arrangement in which the relationship of the shoe to the screw is maintained and in which the shoe has a particularly simple construction, which can be cheaply produced.

In accordance with this invention, a vehicle jack comprises a support leg provided with a foot, an arm pivoted on the leg, a nut and a pivot member each pivotally mounted one on the arm and the other on the leg, a screw member connected to the pivot member and screw engaged with the nut, and a load-engaging shoe pivotally carried by the pivot member, wherein the shoe and the pivot member have formations which mutually engage to limit relative rotation between the pivot member and the shoe.

The shoe preferably comprises a channel-shaped member comprising a pair of spaced walls and a bridging wall, the bridging wall being provided with a load-engaging formation and each of spaced walls having an aperture receiving a portion of the pivot member, each said portion of the pivot member having a flat portion in its peripheral surface and each aperture being shaped complementary to the peripheral surface.

Reference is now made to the accompanying drawings, wherein: Figure 1 is a perspective view of a jack according to the invention; and Figure 2 is a presepective view of broken-away parts of the jack of Figure 1.

The jack shown comprises a leg 11 of channelshape having a cranked portion 12 defining a foot.

The base of the foot is shaped to define first and second relatively angled support surfaces 13, 14.

The first support surface 13 is operative at the initiation of a jacking operation and the jack rolls onto the second support surface 14, when the jack is under load.

Between the ends of the leg, an arm 20, also of channel form, extends into the channel of the leg and is pivoted there-to by a pin 21. The upper end of the leg has a slot 22, in each side wall of the channel, each slot pivotally receiving a respective trunnion 23 of a nut 24, accommodated between the channel side walls. Each slot has an elongate lead-in portion 25 to a rounded bearing portion 27 in which the respective trunnion can rotate. Each trunnion has a flat peripheral surface portion 26 to permit entry of the trunnions into the bearing portions 27 along the lead-in portions 25.

A screw member 30 screw-engages in the nut and is pivotally mounted at one end on the arm 20.

At the opposite end, the screw member carries a handle 31.

A pivot member 40 is rotatably engaged in apertures 41 in the channel side walls of the arm 20, near the end of the arm remote from the leg 11. A bore extends diametrally through the pivot member, substantially mid-way between its ends, and the screw-member 30 extends through the bore.

The end of the screw-member carries a bearing arrangement 42, including a ball race 43, which arrangement bears against the pivot member 40. A sleeve 44 on the screw-member prevents movement of the screw in the pivot member by bearing on the opposite side of the member As the handle 31 is rotated, the screw member also rotates, this being facilitated by the bearing arrangement 42. The length of the screw-member between the nut 24 and the pivot member 40 is lengthened or shortened, depending on the direction of rotation, and the trunnions 23 and the pivot member 40 are caused to turn.

A load-bearing shoe 50 comprises a channelshaped base portion 51 having side walls 52 and a bridging portion 53. The base portion 51 bridges the arm 20 and the side walls 52 have apertures 54, which receive the end parts of the pivot member 40. The pivot member has a flat face 46 on its periphery, extending the full length of the pivot member, and each aperture 54 is of complementary shape. The shoe 50 is thereby supported on the pivot member 40 and is prevented from rotating relative to the pivot member.

The bridging portion 53 of the shoe carries a sinuous member 56, which is shaped to define a channel 57 for engaging with a vehicle flange, or seam.

The leg 11, the arm 20, the base portion 51 of the shoe and the sinuous member 56 are all metal pressings.

The shoe is fixed on the pivot member such that a plane passing centrally through the channel of the sinuous member 56 and through the axis of the pivot member is substantially perpendicular to the axis of the screw. This angular relationship is maintained in all relative positions of the leg 11 and the arm 20, so that the jack is stabilised by the screw when the jack is under load.

Claims

1. A vehicle jack comprising a support leg provided with a foot, an arm pivoted on the leg, a nut and a pivot member each pivotally mounted one on the arm and the other on the leg, a screw member connected to the pivot member and screw engaged with the nut, and a load-engaging shoe pivotally carried by the pivot member, wherein the shoe and the pivot member have formations which mutually engage to limit relative rotation between the pivot member and the shoe.

2. A vehicle jack according to Claim 1, wherein the shoe has an aperture which receives a portion of the pivot member, the aperture and said portion being non-circular in outline and being complementary to prevent relative rotation.

3. A vehicle jack according to Claim 2, wherein the shoe comprises a channel-shaped member having a pair of spaced walls and a bridging wall therebetween, the bridging wall being provided with a load-engaging formation and each of the spaced walls having a said aperture receiving a respective said portion of the pivot member.

4. A vehicle jack according to Claim 3, wherein each said portion of the pivot member has a flat face in its peripheral surface to define said non-circular outline.

5. A vehicle jack according to Claim 4, wherein the pivot member is cylindrical with a flat face extending the full length of the member.

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