GB2134075A - Vehicle jack - Google Patents

Abstract

A vehicle jack has a leg (2) with a lever arm (3) pivoted thereon and operated by a threaded rod (5) via a crank handle (24). The bearer head (4) of the jack is then moved upwards against the lower face of the bodywork of the vehicle to be jacked up. The bearer head (4) has an upwardly open six sided cutout or opening so that jaws are formed on the two sides of the opening for acting against the sides of a flange of a weldment (18) and keeping the jack from slipping out of place. The lower end of the leg (2) is pivoted on a foot (1) in the form of a plate. All the different turnpins (6, 13, 20, 26, and 14) of the pivot joints forming parts of the jack are parallel to each other. <IMAGE>

Description

SPECIFICATION A vehicle jack The present invention is with respect to lifting jacks for motor and other vehicles and more specially but not exclusively to such a jack of the sort having a leg pivoting on a foot to be placed on the ground, a lifting arm pivoted on the leg, a threaded rod for pivoting the arm upwards, and a bearer head on a free end of the arm for acting against a part of a vehicle to be lifted.

In the past a number of vehicle jacks designed on these general lines have been put forward, in the case of which the foot on the leg is made up of a foot plate fixedly joined to the lower end of the leg and having two downwardly turned faces, placed at angle in relation to each other, for resting against the ground. Such a design does however have the shortcoming that slipping of the jack on the ground is likely when it is being righted and more specially when it is rocked through an angle equal to the angle between the two faces.

When this is the case the jack will not be firmly kept in place and there is some chance of its suddenly falling over bodily, more specially if the ground is not firm, so that the vehicle lifted by the upright jack may well be seriously damaged and there may in some cases by danger to life and limb. A further shortcoming with such a jack is that the threaded rod has to be screwed in a nut placed at the top end of the leg, because the threaded rod and its crank handle will be moved far out to the side as it is being screwed outwards so that it will be in the way and may put the vehicle jack off balance. Vehicle jacks as designed so far furthermore have shortcomings in many other respects.

One purpose of the present invention is that of designing a stable jack with a simple structure that is free of the shortcomings noted and furthermore may be produced at a low price.

For effecting these and further purposes that will become clear on reading the present specification, a jack comprises a leg having with a foot to be placed on the ground, a lifting arm pivoted on the said leg, a threaded rod for pivoting the arm upwards, a bearer head on a free end of the arm for resting against part of a vehicle to be lifted, 9 support foot at one end of said leg for supporting said leg on the ground, a pivot joint with a first turnpin joining said support foot to said leg, said foot having a generally plane face to be rested against the ground, said face being turned away from said leg, said turnpin being parallel to said face and normal to a plane of rocking of said leg in relation to said foot, said leg being joined to said lifting arm by a further joint with a second turnpin that is parallel to said first turnpin, said leg further being joined to a thrust bearing on said threaded rod by a pivot joint with a third turnpin that is parallel to said first and second turnpins, said rod running threadedly through a nut that is joined to the lifting arm between said bearer head and said second turnpin by a further pivot joint with a fourth turnpin parallel to said first and second turnpins.

Because of the lower pivot joint between the leg and the support plate or foot and the middle pivot joint joining the lifting arm to the leg in the invention the new jack takes the form of a simple twin joint vehicle jack, because all the load forces are transmitted by these two joints to the foot and for this reason to the ground without there being any chance of the jack as such rocking or slipping.

Because of this design all the body of the jack is safely supported on its foot whatever level it has been lifted to.

Further details and useful developments of the present invention will be seen from the account now to be given and from the claims, such further outgrowths of the invention being responsible for useful effects when the jack is used.

One working example of the invention will be seen in the figures herein.

Figure 1 is a side view of a vehicle jack in one position while being used.

Figure 2 is a further side view of this vehicle jack in its folded, put away position.

Figure 3 is a cross section of the section material used to make the leg and the lifting arm.

The main parts of the jack are a foot 1, an upright leg 2, a lifting arm 3, a bearer head 4 and a threaded rod 5, that are joined together by further parts.

At its lower end the leg 2 is joined to the foot 1 by a lower pivot joint with a turnpin 6, that is in the main parallel to the ground 7 and is normal to the plane of rocking of the leg 2. To this end the foot 1 has two support ears 8 or lugs that are bent up from the plane of the plate or foot 1 at a right angle thereto, such ears being for example in the form of pieces of sheet metal. Between the support ears 8 the flanges 9 of a piece of U section which the leg 2 is made are placed. The support ears 8 and the flanges 9 of the piece of section have holes that are lined up with each other and in which turnpin 6 is placed.

The foot 1 is made wider at its two sides, that is to say on the two sides of the area between the lower ends of the ears 8, in the form of wings 10, whose outer edges 11 are bent downwards. The wings 10 furthermore have inwardly pressed ridges 1 2 or corrugations. The edges 11 are responsible for stopping the foot 1 and the jack generally from slipping backwards or forwards. It is furthermore possible to have teeth or the like on the long or short sides of the foot, such teeth being formed by pressing and being responsible for stopping the jack from slipping out sideways by biting into a hard floor.The ridges or corrugations 1 2 in the wings 10 may be forced into the ground 7 when the jack is being used and are themselves very useful for safely keeping the jack in the desired position on the ground without any slipping.

The slifting arm 3 is joined to the middle part of the leg 2 by a middle pivot joint with a turnpin 13 whose axis of rocking is parallel to that of the lower pivot joint so that it may be rocked upwards or downwards as desired. The bearer head 4 may be rockingly joined to the free end of the lifting arm 3 by a pivot joint with a turnpin 14 that is parallel to the turnpins 6 and 13. In keeping with one possible form of the invention however it is possible for the bearer head 4 to be fixed on the free end of the lifting arm 3 so that it may not be rocked in relation thereto. Furthermore it would be possible for the bearer head 4 to simply be locked in openings in the lifting arm 3 and kept in place therein by a gripping effect.

The bearer head 4 itself is one sided or assymmetrical in design with a cutout 1 5 going through it from side to side parallel to the turnpin 14, such cutout 1 5 being generally six sided in cross section and being open at one, top side so that opposite jaws are formed. The hexagonal sides 1 6 and 1 7, forming the lower faces of such jaws and that have the opening between them may be used for bearing and locking against the sides of an outwardly running or flanged weldment 18 in the lower part of the bodywork 19 of a motor vehicle. It is possible to have a middle positioning ridge in the cutout 15, the ridge being about 5 mm wide. The bearer head 4 is best made of synthetic resin with a high strength.

At its top end the leg 2 is joined by a top turnpin 20, that is parallel to the lower turnpin 6 and to the middle turnpin 13, to a thrust bearing 21 for the threaded rod 5. The thrust bearing 21 is best made in the form of a thrust ball bearing. On the end, nearest to this bearing, of the threaded rod 5 there is fixed (for example by swaging) a sleeve 22, that has a cross hole 23 into which a crank handle 24 may be fitted.

For its part the threaded rod 5 is screwed into a threaded nut 25, that is rockingly joined to the lifting arm 3 by a turnpin 26, this turnpin as well being parallel to the turnpins 6, 13 and 20 of the leg 2 and having its threaded nut 25 generally in the middle of the lifting arm 3 between the turnpin 14 of the bearer head 4 and the middle turnpin 13 of the jack leg.

The girder or section stock with a U cross section to be seen in figure 3 and used for making the leg 2 and the lifting arm 3 is best reinforced by inner or outer grooves 27 and 28. It is lastly to be noted that the leg 2 has a stop face 29 at its lower corner for resting against the top face of the foot next to a stop face 30 thereon. Such stop faces may be designed for defning the folded up and lowered position to be seen in broken lines in figure 1 and the upper end position to be seen in full lines therein.

The workings of the jack will be readily seen from the figures and the account given so far, attention being given more specially to figure 1 with the vehicle jack in the lowered position in broken lines and the upper position in full lines as noted.

As will be seen from figure 2 the jack only takes up a small amount of space in its folded up position.

The invention is not limited to the working example of which an account has been given in connection with the figures herein, and the claims are to be read without limitation to such details and so as to cover all designs with the main ideas of the invention.

Claims (14)

CLAIMS.

1. A jack comprising a leg having with a foot to be placed on the ground, a lifting arm pivoted on the said leg, a threaded rod for pivoting the arm upwards, a bearer head on a free end of the arm for resting against part of a vehicle to be lifted, a support foot at one end of said leg for supporting said leg on the ground, a pivot joint with a first turnpin joining said support foot to said leg, said foot having a generally plane face to be rested against the ground, said face being turned away from said leg, said turnpin being parallel to said face and normal to a plane of rocking of said leg in relation to said foot, said leg being joined to said lifting arm by a further joint with a second turnpin that is parallel to said first turnpin, said leg further being joined to a thrust bearing on said threaded rod by a pivot joint with a third turnpin that is parallel to said first and second turnpins, said rod running threadedly through a nut that is joined to the lifting arm between said bearer head and said second turnpin by a further pivot joint with a fourth turnpin parallel to said first and second turnpins.

2. A vehicle jack as claimed in claim 1 wherein said foot has opposite bearing ears bent away at a right angle from the said plane of said foot, said ears having holes to take up said first turnpin, same furthermore running through holes in two flanges of said leg, that is made of U-section material.

3. A vehicle jack as claimed in claim 2 wherein the foot has wings running out from the said plane between said ears, said wings having angled edges.

4. A vehicle jack as claimed in any one of claims 1 to 3 characterized in that the wings on the foot have ridges or corrugations pressed thereinto or have teeth pressed thereon for biting into the material of a floor.

5. A vehicle jack as claimed in any one of claims 1 to 4 wherein said leg has stop faces for acting on stop faces on said foot and defining at least one position of said foot in relation to said leg.

6. A vehicle jack as claimed in any one of claims 1 to 5 wherein the arm and the leg have a U cross section with flanges that are reinforced by grooves running in the length direction thereof.

7. A vehicle jack as claimed in any one of claims 1 to 6 wherein said foot has long and short sides and said long sides are toothed.

8. A vehicle jack as claimed in any one of claims 1 to 7 wherein said bearer head is fixed on a free end of said lifting arm and may not be moved in relation thereto.

9. A vehicle jack as claimed in any one of claims 1 to 7 wherein said bearer head is joined to a free end of said lifting arm by a pivot joint with a turnpin parallel to said first turnpin.

10. A vehicle jack as claimed in claim 8 or claim 9 wherein the bearer head has an asymmetrical outline with a cutout therethrough, said cutout being generally six sided and having one side open between two jaws, one side of each of said jaws being formed by a different one of said six sides of said cutout and being designed to take effect on the two sides of a flanges forming part of a weldment on a lower part of bodywork of a vehicle to be jacked up.

1 A vehicle jack as claimed in claim 10 wherein said cutout in the bearer head has a middle support ridge therein.

12. A vehicle jack as claimed in any one of claims 1 to 11 wherein said thrust bearing is a thrust ball bearing.

13. A vehicle jack as claimed in any one of claims 1 to 12 comprising a sleeve on an end of said threaded rod near said bearing, said sleeve being designed to have a crank handle fitted into it for operation of said jack.

14. A vehicle jack as claimed in claim 13 wherein said sleeve is swaged onto the end of the threaded rod.

1 5. A vehicle jack as claimed in claim 1 substantially as described hereinbefore with reference to and as illustrated in the figures 1 to 3 herein.

1 6. Any novel feature or combination of features herein described.