GB2203090A

GB2203090A - Device for removing bushes

Info

Publication number: GB2203090A
Application number: GB08806762A
Authority: GB
Inventors: Roy Higgins
Original assignee: Individual
Current assignee: Individual
Priority date: 1987-04-02
Filing date: 1988-03-22
Publication date: 1988-10-12
Anticipated expiration: 2008-03-22
Also published as: GB8806762D0; GB2203090B

Abstract

A device 20 for removing a spring bush 10A from a spring leaf 12 of motor vehicles after removal of a spring bolt comprises (spacer tube means 30) bearing against the spring leaf 12 on one side thereof, means (collar 32) bearing against the spring bush 10A from the other side and means (threaded bolt 22 and nut 24) for drawing said means 32 bearing against the spring bush 10A towards the means 30 bearing against the spring leaf 12. The drawing of the collar 32 towards the spacer tube 30 by nut 24, upon rotation of the bolt 22, causes the bush 10A to be pushed out of the leaf 12 and into the tube 30 and a new bush 10B to be replaced in the leaf 12. The device includes a fixed nut 26 and a washer 28. A thrust ring 40 having a thrust bearing 42 against which nut 26 bears may be disposed between the nut 26 and the tube 30 (Figure 4 not shown). <IMAGE>

Description

Device for removing bushes DESCRIPTION This invention relates to a device for removing bushes, especially suspension bushes say from spring leafs of motor vehicles The suspension systems of, for example, some Landrovers 'include spring leafs mounted on spring shackle bolts with bushes therebetween. Later vehicles are fitted with coil springs but include bushes in radius and Panhard rod arms These bushes comprise an outer metal tube, and an inner metal tube held together by an infill of bonded rubber. The normal method of extracting say spring bushes, as described in the Landrover Workshop Manual, often involves removing the springs from the vehicle, an operation which frequently results in bolt shearing.The inner tube of the bush has to be removed first, which may not be too difficult as the usual reason for replacing bushes is that the rubber infill has perished or separated from the metal tubes. Otherwise, the rubber has to be burnt away, which can be hazardous due to resultant toxic fumes and the proximity of the fuel tank. However, to remove the outer metal tube a slot has to be hacksawed through the tube to toe lease its grip on the spring. There are twelve such bushes in a Landrove so that teplaeement of all of them is a difficult and time-consuming task and additionally expensive if other parts of the vehicle are damaged in removing the bushes.

The object of this invention is to provide a device for removing suspension bushes, preferably also with replaçement in one operation, without having to remove suspension parts.

According to the invention there is provided a device for removing a bush from a bush location after removal of a through bolt, comprising means bearing against the bush location on one side thereof, means bearing against the bush from the other side and means for drawing said means bearing against the bush towards the means bearing against the bush location.

By bush location is meant that part or member in which the bush is fitted, such as a spring leaf, suspension arm or Panhard rod arm.

The means for drawing is preferably a screw threaded member having a fixed head at one end and a threaded nut on the other, whereby either rotation of the threaded member or the threaded nut draws the means bearing against the bush towards the means bearing against the bush location. Preferably it is the threaded member that is rotated. The nut itself may bear on the bush, alttoiigh an intermediate collar is preferred. Rotation of the threaded member can then force the bush along the screw threaded member and out of the spring leaf.

The means bearing against the bush location, such as a spring leaf, is preferably tubular and at its other end has the fixed head of the screw threaded member against it. The tubular member should be long enough to receive the extracted bush. Preferably a thrust ring and bearing is interposed between the fixed nut and the tubular member to facilitate operation of the device of the invention and to prevent damage to the fixed or threaded nut in use. Different diameters of tubular member may be provided for the device of the invention so that differently sized bushes may be removed and replaced using the same basic extractor.

To replace the bush in one operation, a replacement bush may be positioned on the screw threaded member between the collar and the threaded nut so that as the old bush is being forced out by rotation of the screw threaded member the new bush is forced into its place.

The device of the invention thus provides a simple and effective means of performing a hitherto difficult and time consuming task. Advantages arising From the invention include the following 1. A reduction in workshop time and consequent reduction in labour cost; 2. A reduction in damage to parts, such as the U-bolts; 3. Workshop facilities are not essential; 4. A reduction in vehicle body work damage and risk of personal injury.

This invention will now be further described with reference to and as illustrated in the accompanying drawings, in which Figure 1 is a longitudinal section through one form of spring bush extractor in use; Figure 2 is a section on line AA of Figure 1; Figure 3 is a section on line BB of Figure 1; and Figure 4 shows another form of spring bush extractor.

Referring to Figures 1 to 3 of the drawings, a motor vehicle spring bush 10A is shown in place in a spring leaf 12. The spring bush 10A consists of an outer metal sleeve 14 and inner metal sleeve 15 and a rubber joint 16 therebetween. The spring bush 10A is to be replaced by spring bush 10B.

The spring bush extractor 20 comprises a scres-threaded bolt 22 having a fixed head 24 at one end and a nut 26 at tbe other. The nut 26 is provided with parallel flats for application of a spanner. The fixed head 24 has a coventional hexagonal head. From the fixed head 24 the components of the extractor 20 on the bolt 22 are a plate washer 28 and a spacer tube 30 against which the plate washer bears. The other end of the tube 30 bears against the spring leaf 12. The tube 30 is sufficiently long to accommodate the spring bush lOA when removed. After the spring leaf 12 is a collar 32 that bears against the spring bush 1DA. Next is the new spring bush lOB followed by the nut 26.

By rotating the bolt 22 whilst holding the nut 26, the new bush lOB and the collar 32 all move along the bolt to push the old bush lOA out of the spring leaf into the spacer tube 30.

The sequence of steps recommended for using the extractor 20 on a Landrover is as follows: 1. Jack up vehicle under the chassis until one pair of wheels are raised 50mm (2") clear of ground.

2. Support chassis on secure blocks, remove jack.

3. Place jack under axle on the side to be wormed on, and jack up the axle until the spring shackle bolts iTe free of any load.

4. Remove all three spring shackle bolts, and shackle plates.

5. Lower axle until wheel rests on the ground. This will lower the spring ends clear of the support bracket at the front (fixed) end.

6. Fit the bolt 22 through the washer 28 and spacer tube 30, and slide into the spring bush 10A. From the other side, slip the --collar 32 over the inner tube of the spring bush 10A, followed by the replacement bush lOB which must be properly located in the collar. Finally thread nut 26 on to the bolt 22.

7. Using a socket or spanner, tighten the bolt 22 and carry on tightening until the new bush has been drawn fully onto the spring. This operation will, at the same time, extract the old bush.

8. Repeat the operation on the other spring bush and the one located in the chassis.

9. Lift the axle until the front is aligned with the chassis bracket holes, replace the shackle bolt. Similarly, raise or lower the axle to align the rear bolts in the shackle plates.

10. If the existing bush does not move under the full force of the extractor, strike the spring end sharply with a light hammer to break the bond. Do not use more than normal hand force on a normal ratchet or ring spanner to operate the extractor since this may cause damage.

Where the old bush is being particularly obstinate, fit the nut 26 directly to the bolt, without fitting the collar 32 or the new bush lOB. This will apply force directly to the outer tube of the bush.

When the initial bond is broken, proceed through steps 6-9 above.

Turning to Figure 4, a spring bush extractor is shown that is in most respects identical to the extractor of Figures 1 to 3. Therefore, like parts have been given the same reference numerals and only the differences will now be described. Between the fixed nut 24 and the tubular member 30, is a thrust ring 40 containing a thrust bearing 42 against which the nut 24 bears.

Operation of the. device of Figure 4 is identic l to the operation of the device of Figures 1 to 3.

Having described the invention in relation to removal of a spring bush from a spring leaf, it will be appreciated that the invention will be equally applicably to removal and replacement of bushes from other locations such as in alternative suspension systems.

Claims

A A device for removing a bush from a bush location, after removal of a through bolt, comprising means bearing against the bush location on one side thereof, means bearing against the bush from the other side and means fon drawing said means bearing against the bush towards the means bearing against the bush location.
2. A device as claimed in claim 1, wherein the means for drawing is a rotatable screw threaded member having a fixed head at one end and a threaded nut on the other.
3. A device as claimed in claim 2, further comprising a collar for between the threaded nut and the bush.
4. A device as claimed in claim 1, 2 or 3, wherein the means bearing against the bush location is tubular and at its other end has the fixed head of the screw threaded member against it.
5. A device as claimed in claim 4 further comprising a thrust ring interposed between the fixed nut and the tubular member.
6. A method of removing a bush from a bush location after removal o! a through Bolt comprising fitting a device as claimed in any one of claims 1 to 5 to the bush and Totating the screw-threade ember thereof.
7. A method as claimed in claim 6 comprising the further step of replacing the bush by positioning a replacement bush on the screw threaded member between the collar and the threaded nut.
8. A device for removing a bush from a bush location after removal of a through bolt substantially as hereinbefore described with reference to and as illustrated in Figures 1 to 3 or Figure 4 of the accompanying drawings.
9. A method for removing and optionally replacing a bush in a bush iocation after removal of a throngh bolt substantially as hereinbefore described with reference to Figures 1 to 3 or Figure 4 of the accompanying drawings.