BACKGROUND ART A harmonic balancer is typically mounted to an end of a crankshaft of an engine and absorbs vibrations produced by the crankshaft and flywheel assembly of the engine. Harmonic balancers for some types of vehicles have a hub, an outer ring and spokes extending between the hub and the ring. A central opening of the hub receives the end of the crankshaft. The outer ring has a rubber lining. Threaded apertures may be located in the spokes and may extend through the spokes.

In some types of vehicles there is little clearance between an engine and a radiator of the vehicle, and hence removing a harmonic balancer from a crankshaft of the engine may be difficult, and if the harmonic balancer is not carefully removed, the crankshaft may be damaged.

The present inventor has now developed a harmonic balancer puller that overcomes or at least minimises the problems associated with removing a harmonic balancer referred to above.

SUMMARY OF THE INVENTION According to the present invention, there is provided a harmonic balancer puller for removing a harmonic balancer of the type having a hub, an outer ring and spokes extending between the hub and the ring, wherein the harmonic balancer puller has: a body; retainers extending from the body for engaging the spokes; and a drive extending from the body and having an end movable relative to the body, whereby in use the retainers are engaged with the spokes and the drive is engaged with an end of a crankshaft to move the harmonic balancer away from

the end of the crankshaft as the end of the drive is moved relatively away from the body.

Any suitable type of drive may be used but preferably the drive comprises a jacking arrangement. The end of the drive may be moved, for instance, manually, pneumatically or hydraulically. Preferably, the drive includes a jacking bolt extending through a central threaded opening in the body, and the end of the bolt is movable relatively towards and away from the body by rotating the jacking bolt relative to the body.

The body may be of any suitable size, shape and construction.

Preferably, the body comprises a disk. A rim may extend from the disk. The central threaded opening in the body may be located in the disk. A boss may extend around the opening.

The body may have openings that coincide with threaded apertures in the spokes of the harmonic balancer. The harmonic balancer puller may have bolts extending through the openings for releasably securing the body to the harmonic balancer. The openings may be threaded or they may be radially extending slots so that the bolts may be positioned along the slots such that they coincide with spaced apertures of different types of harmonic balancers.

The retainers may be of any suitable size, shape and construction. The retainers may engage the spokes in any suitable way. The retainers may all be identical to one another in configuration or they may differ from one another.

Preferably, each retainer is a hook adapted to extend around a respective spoke of the harmonic balancer. The retainers may extend from the disk or from the rim of the body. Hooked end portions of the hooks may be arcuate and extend part way around a notional circumference identical to a circumference of the disk.

The body and retainers may be of unitary construction or they may comprise two or more connected pieces. The pieces may be attached to one another in any suitable way. The pieces may be, for example, welded, glued pinned or riveted together.

The harmonic balancer puller may be made of any suitable material or materials. Preferably, the harmonic balancer puller is made of metal.

Preferred embodiments of the invention will now be described by way of example with reference to the accompanying drawings.

E EF DZ Wed Figure 1 is a perspective view of a harmonic balancer puller according to a first embodiment of the invention ; Figure 2 is a perspective view of part of the harmonic balancer puller shown in Figure 1 ; Figure 3 is a detailed plan view of Figure 2 ; Figure 4 is a cross-sectional through plane A-A of Figure 3; Figure 5 is a bottom perspective view of part of the harmonic balancer puller shown in Figure 2; Figure 6 is a bottom perspective view of part of a harmonic balancer puller according to a second embodiment of the invention; Figure 7 is a bottom plan view of Figure 6; and Figure 8 is a cross-sectional through plane A-A of Figure 7.

BEST MODE AND OTHER MODES OF CARRYING OUT THE INVENTION Like reference numerals refer to like features.

Figure 1 shows a harmonic balancer puller 1 having a body 2, three hooks 3 for engaging spokes of a harmonic balancer (not shown) and a jacking bolt 4.

Referring now to Figures 1 to 5, the body 2 comprises a disk 5 and a rim 6 extending from the disk 5. A threaded opening 7 extends through a centre of the disk 5.

The hooks 3 extend from the rim 6 and are equidistantly spaced from one another. Hooked end portions 8 of the hooks 3 are arcuate and extend part way around a notional circumference identical to a circumference of the disk 5. A spoke of a harmonic balancer is locatable within a space 9 between each hooked end portion 8 and the rim 6.

The body 2 and hooks 3 are of unitary construction and are made of metal.

Referring now to Figure 1, the jacking bolt 4 has a hexagonal head 10 and a threaded shank 12. The threaded shank 12 extends through opening 7 and an end 11 of the jacking bolt 10 is movable relative to the body 2 by rotating the bolt 4 relative to the body 2.

The harmonic balancer puller 1 is particularly suited to pull harmonic balancers from crankshafts of engines six cylinder Ford Falcon models produced after the year 1997, Commodore VN-1988 to current V6 models, and General Motors GEN III V8 engines.

In order to pull a harmonic balancer from an end of a crankshaft, the jacking bolt 4 is rotated such that end 11 does not extend past the rim 6. The hooks 3 are then manoeuvred into engagement with the spokes of the harmonic balancer. Jacking bolt 4 is then rotated such that end 11 is driven into engagement with the crankshaft, and continued rotation of the jacking bolt 4 results in end 11 extending relative to the body 2 and the harmonic balancer is pulled from the end of the crankshaft.

Figures 6 to 8 show another harmonic balancer puller 20 that is similar to harmonic balancer puller 1, but a jacking bolt (like bolt 4) has been omitted from the figures. Harmonic balancer puller 20 has a body 21 comprising a disk 21 and three hooks 22 extend from the disk 21. A boss 24 having a threaded opening 23 is located at a centre of the disk 21.

Harmonic balancer puller 20 is used in the same way as puller 1, except that puller 20 has three radially extending slots 25 in the disk 21 that coincide with threaded apertures in spokes of a harmonic balancer. Bolts (not shown) are extendable through the slots 25 and releasably secure the disk 21 to the harmonic balancer. Bolts may be positioned along the slots 25 so that they coincide with spaced apertures of different types of harmonic balancers.

In this way, the harmonic balancer puller 1,20 may be used to carefully remove a harmonic balancer in a situation where there is little clearance between an engine and a radiator of a vehicle.