GB2174066A - Jacking tractors etc - Google Patents

Abstract

A vehicle jack 10 for use in conjunction with a vehicle hoist on, e.g an agricultural tractor, comprises a structural framework having a base portion 14 and an adjustable length leg portion 16, the leg portion being contactable with an appropriate jacking point of the vehicle and the base portion being attachable at its free end to the vehicle hoist. <IMAGE>

Description

SPECIFICATION Vehicle jack This invention relates to vehicle jacks and is particularly, but not exclusively concerned with jacks for vehicles which incorporate hydraulic lifting apparatus, for example, agricultural tractors.

It is quite commonly required to change the wheels, either back or front of such a tractor and lifting or jacking the tractor can be an awkward and time consuming operation. The present invention seeks to provide a means whereby the hydraulic lifting apparatus can be used to life one, or other, or both of the vehicle wheel sets from the ground.

Accordingly the present invention provides a jacking device for a vehicle having hoisting means, such as a tractor, the jacking device comprising of structural frame work having a base portion and a leg portion, an end of the base portion being connected to an end of the leg portion, the free end of the base portion being arranged to be securable to a vehicle hoisting means and the free end of the leg portion being arranged to be located under a suitable jacking point of the vehicle to be lifted.

In one arrangement according to the invention, the structural framework comprises two side frames spaced apart and joined together by adjustable length tie bars. Each side frame comprises one of the structural members making up each of the base and leg portions of the framework.

The leg portions are adjustable in length and the base and leg portions can include a brace joining them together.

The two frame members making up the base portion have at their ends suitable connectors, e.g.

pins, bolts, shackles etc., enabling the framework to be connected to the linkage of the hydraulic hoist. The leg portions have brackets at their free end to enable the framework to be located with respect to one of the vehicle axles or any other appropriate jacking point of the vehicle. The part of the base portion which contacts the ground can be provided with feet so as to spread the load and prevent the framework from sinking into the ground.

The present invention will now be more particularly described with reference to the accompanying drawings in which Figure 1 is a side elevation of one form of jacking device according to the present invention, Figure 2 is a view of arrow A in Figure 1 and Figure 3 is a view on arrow B in Figure 1.

Referring to the drawings, the jacking device comprises a structural framework 10 consisting of two side frames 12. Each side frame comprises a base member 14 and a leg member 16. Each base member and leg member are joined to a stub shaft 18 and to each other at one of their free ends. A brace 20 is also provided between the base and leg members to stiffen the structure.

Each leg portion is adjustable in length by means of a tube 22 located in each leg portion 16.

Each leg portion and tube 22 is provided with appropriately spaced openings 24 and a pin 26 is used to locate the tube 22 with respect to each leg portion 16.

At the free end of each base portion lugs 28 are provided to enable the hoist to be attached to the structural framework by means of, for example, shackle pins. Aiso at the free end of each base portion are stub shafts 30.

The two side frames are joined together by means of tubes 32, 34 which are located on the stub shafts 18 and 30 respectively. The tubes 32 and 34 and stub shafts 18 and 30 can be provided with apertures and pins in order to provide a variable spacing between the two side frames. In the example illustrated, openings in the stub shaft and tubes are not provided but the spacing between the two side frames can be adjusted to some extent since the stub shaft and tubes are relatively movable.

The free ends of the tubes 22 are provided with suitably shaped brackets 36 to locate with any suitable jacking point on the vehicle, for example, an axle or at the point where the vehicle hoist is attached to the vehicle.

In order to use the jacking device, the structural framework is assembled as illustrated in Figures 1, 2 and 3, and the length of the leg portions is adjusted to suit the vehicle to be hoisted and the distance from the ground by which the vehicle is to be hoisted. Also the spacing between the side frames is adjusted as appropriate. The complete framework is placed under the vehicle with the brackets on the leg portions located, for example, under the rear axle. The vehicle hoisting apparatus is lowered so that the hoist linkage can be connected to the iugs 28 by shackle pins (not shown).

Throughout this operation the stub shaft 18 and tube 32 are in contact with the ground.

When the hoist linkage has been connected to the framework, the hoist is operated bringing the leg portions to the vertical position thereby lifting the rear wheels of the vehicle clear of the ground.

The vehicle is now supported by a strong and stable structure enabling the wheels to be changed or any other work to be done to the vehicle.

Referring to Figure 4, at the same time as raising the rear wheels of the vehicle, the front wheels can be raised as well by use of a frame 38 shown in Figure 4. The frame 38 comprises two adjustable length leg members 40, a top member 42 and a brace 44.

If the frame 38 is placed under an appropriate location at the front of the vehicle with the legs having been set to an appropriate length, when the rear of the vehicle is lifted by means of the jacking device, the front of the vehicle will be lifted from the ground as well.

The framework 10 need not be essentially triangle in form since the invention essentially comprises a lever to lift the vehicle and the vehicle hoisting apparatus provides the effort needed to use the lever to lift the vehicle. Naturally if a hoisting apparatus is provided at the front of the vehicle, this can be used in association with the structural framework to lift the front of the vehicle and a frame similar to frame 38 can be located at the rear of the vehicle so that both sets of vehicle wheels can be raised at the same time.

The structural framework and the frame 38 can be formed from tubing, or any suitable section or combination of sections and can be welded, bolted or otherwise joined together.

Claims (1)

1. A jacking device for a vehicle having hoisting means such as a tractor, the jacking device comprising a structural framework having a base portion and a leg portion, a free end of each of the base portion and the leg portion being joined together, the remaining free end of the leg portion being arranged to be located at an appropriate jacking point of the vehicle and the remaining free end of the base portion being arranged to be connectable to the vehicle hoisting means.

2. A jacking device according to claim 1 in which the leg portions are adjustable in length.

3. Ajacking device according to claim 1 in which the structural framework comprises two side frames being attachable together by adjustable length joining means.

4. A jacking device according to claim 3 in which each side member comprises a base struc tural member and a leg structural member each of which is attached to a stub shaft extending transversely to both the base member and the leg member, a further stub shaft being attached to the remaining free end of the base member and extending transversely to the said base member and parallel to the first stub shaft.

6. A jacking device constructed and arranged for use in operations substantially as herein described.