GB1595999A

GB1595999A - Spigot assembly for locating the knuckle of a vehicle suspension or steering member

Info

Publication number: GB1595999A
Application number: GB1114878A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1977-03-22
Filing date: 1978-03-21
Publication date: 1981-08-19
Also published as: CA1068734A

Description

(54) A SPIGOT ASSEMBLY FOR LOCATING THE KNUCKLE OF A VEHICLE SUSPENSION OR STEERING MEMBER (71) We, WALLACE GORDON CHALMERS, a Canadian citizen of 74 St.

Clair Avenue West, Toronto, Ontario, Canada and HANS VIERECK, a German citizen of 106 St. Andre, Chateauguay Ville, Quebec, Canada, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed to be particularly described in and by the following statement: The present invention relates to means for locating the end of an elongated member of a vehicle to a relatively movable part of the vehicle system. More specifically. the invention provides a spigot assembly for attaching the knuckle of a member of a vehicle to a relatively movable part of the vehicle, and has particular application to rods used in vehicle suspension steering systems.

Many vehicle suspensions, and steering systems, have members which transmit tension or compression between relatively movable parts. Generallv, such members have a knuckle at one end surrounding a cylindrical bushing which is located by a spigot or pin connected to the parts to be located, the assembly allowing pivoting of the member about the pin or spigot.

As an example, my prior Canadian Patent Number 958,729, issued December 3, 1974, shows examples of vehicle suspensions having lower torque rods 5, 105 connected to suspension parts by various means. An example of a spigot type,- or single ended type connection is shown in Figure 3 of this prior patent, the spigot being a projecting part of a hollow pin 40 which has a hardened chrome finish with a smooth machined and polished surface, and which is held within an accurately machined bore within a suspension part 22. The pin receives a hollow bushing 42 held within the knuckle end of a torque rod, which is held on the pin by washer 44 and transverse screw 45.Another arrangement is shown in Figure 9 of this patent, where the end of a torque rod is held in a clevis in part 103 by a hollow pin 175 which is also hardened and machined, and with a polished surface, and which fits within accurately machine bores in the sides of the clevis, being retained in place by screw 176.

These constructions of my prior patent are relatively expensive in that they necessitate machining both of the pins and of the bores into which they fit, since the pins must fit with very close tolerance within the bores to avoid any slackness. The provision of threaded transverse bores for the retaining screws also adds to the expense.

The present invention provides an arrangement which is cheaper in manufacture and assembly than that described in my aforesaid prior patent, and those in general use, and in which parts can be removed and replaced (for example for the replacement of bushings) much more quickly than with prior art arrangements.

According therefore to the present invention there is provided a spigot assembly for attaching a knuckle of a member of a vehicle to a relatively movable part of the vehicle via a bushing, said bushing having a bore and ends and being held within said knuckle, said spigot assembly comprising: a rigid metal spigot part having a base portion arranged, in use, to be rigidly secured to said vehicle part and a projection extending from said base, said projection having first tapered annular surface means facing axially outwardly of the projection and having a bore co-axial with said first annular surface means; a rigid metal cap part having second tapered annular surface means complementary to and engageable with that of said projection and having a bore co-axial with said annular surface means of the cap part; and fastening means receivable in said bores for fastening said spigot and cap parts together with said first and second tapered annular surface means engaged in mating relation with one another; said first and second tapered annular surface means being arranged to hold the cap part in co-axial alignment with the spigot part so long as the fastening means holds such annular surfaces in mating relation to one another, and wherein both said projection and said cap part further each include an outer surface co-axial with their tapered annular surface means, each of said parts further having an annular flange extending outwardly of and co-axial with said outer surface and arranged so that, in use of the spigot assembly with said spigot and cap parts fastened together by said fastening means, said outer surfaces and annular flanges can engage the bore and ends respectively of the bushing held within said knuckle to provide locating means for said bushing.

Each of the first and second annular tapered surface means preferably lies in a frusto-conical surface co-axial with said projection and cap part bores thereby to stabilize the cap part relative to the spigot part under the influence of bending moments.

Preferably, each of the first and second tapered annular surface means comprise a single frusto-conical surface.

Preferably the spigot assembly such that the said projection has a recess defined in part by said first tapered annular surface means; the bore of said cap part extends from the second tapered annular surface means of said cap part to a co-axial recess provided in said cap part; and said fastening means comprising a nut and a bolt, said bolt arranged to extend through said projection and cap part bores when said parts have their annular surface means engaged in mating relationship with one another; the said nut being receivable on said bolt within said recess of the cap part.

With the spigot assembly as described, there is no need for any surface to be machined. I have found that as cast surfaces are suitable both for the cylindrical surface of the projection (and that of the cap when this has a cylindrical surface), which surface is in contact with the bushing, and as cast surfaces are also suitable for the engaging frusto-conical surfaces of the two parts. The conical nature of these surfaces insures adequate co-axial alignment of the two parts even with irregularities of casting, and likewise such irregularities do not cause any slackness in the assembly. Thus, all machining costs are avoided. Furthermore, the parts are very simple to assemble and disassemble, as when it is required to replace a torque rod or torque rod bushing.

The invention will be described in more detail with reference to the accompanying drawings, in which: Figure 1 shows a diagrammatic plan view of a vehicle suspension using the spigot assembly of this invention, Figure 2 shows a detail of a portion of Figure 1 in which a part of the spigot assembly and associated end of a torque rod are sectioned, Figure 3 shows a partial view of the underside of the spigot part as seen in the direction A of Figure 2, and Figure 4 shows a view on 4-4 of Figure 2 but showing the spigot part only with the nut and bolt, the cap, and the torque rod removed.

Figure 1 shows certain components of a tandem axle truck suspension basically similar to that of my Canadian Patent Number 782,947, issued April 16, 1968, and especially shows the parts which are illustrated in full in Figures 1 and 3 of that patent. In this suspension, each axle 10 is located relative to side chassis members 12 by a V-shaped arrangement of upper torque rods 14, and by a pair of longitudinal lower torque rods which are not shown in Figure 1. Also not shown in Figure 1 are rubber springs which support the chassis members above the axles, via longitudinal beams which have their ends supported by the ends of the axles. This type of suspension is however only described by way of being a typical environment for the use of torque rods 14, or like members, which may be found in many suspension and steering systems.

The rods 14 have at each end an enlarged eye or knuckle 20, in the form of a short cylinder transverse to the rod and having a bore which is of convergent-divergent form as shown in Figure 2 and which is cast on the end of the rod and which requires no machining. Into this bore is inserted a resilient elastomeric bushing 22, preferably of rubber. having an outer shape conforming to the shape of the bore, and having an inner surface of uniform diameter. This inner surface is located by a spigot assembly 24, three of which identical assemblies are illustrated in Figure 1, and one of which is shown in detail in Figure 2.

Referring to Figure 2, the spigot assembly is shown as including, basically, a spigot part 26, a cap part 28, and bolt means 30 which hold the two parts together.

The spigot part 26 is a casting which has a flat base 32 which, as shown in Figure 4, has four holes whereby it is attached to the chassis member 12 by bolts 33. Projecting upwardly from the base is a hollow angled support 34 having part cylindrical walls 36 which surround an axis which is off-set at 280 from the normal to the base. The top of the support 34 is solid with a generally cylindrical projection 38, the walls of which are joined by a radius at the foot of the projection to an annular bearing surface 40 which surrounds the foot of the projection.

The projection extends for a length slightly more than half the length of the bushing 22 of a torque rod end received thereon, and has at its outer end an axial recess largely defined by a frusto-conical surface 44 which diverges from the base of the recess and from an axial bore 46 within the projection.

The bore 46 is designed to take a bolt 30', and the underside of the support 34 is provided with a triangular recess 34a, the form of which is shown in Figure 3, and the sides of which are designed to prevent rotation of the hexagonal head 30a of the bolt. The bolt is placed within the bore, as shown, before the part 26 is secured to a chassis member or like part, and is retained in the position shown by means of a locking ring 31 which engages in the recess of the projection near to its bottom.

The cap part 28 is of hollow, cup-like form, having a projection with an outwardly facing frusto-conical surface engaging the surface 44 of the recess in the spigot part.

The cap part also has a generally cylindrical surface 60 which forms a continuation of the surface of the projection 38, although being of slightly less length. This cylindrical surface is joined by a radius to an annular bearing surface 62 which faces the surface 40. The hollow interior of the cap part receives the screw threaded portion of bolt 30', and has a flat bottom area 64 engaged by a nut 30b on the bolt.

During assembly of a suspension as illustrated in Figure 1, the spigot part is firstly fitted with the bolt 30', and the retaining ring 31, and is then bolted onto the respective chassis member 12. The spigot parts may also be made suitable for welding onto a chassis or other part. A torque rod 14 is then located on the projection of the spigot, as shown in Figure 2, and the cap part 28 then placed in position also as shown in Figure 2. The nut 30b is then put in place and tightened until the complementary frusto-conical surfaces of the spigot and cap parts are drawn tightly together. Although both the spigot and cap parts are in as-cast condition, so that the frusto-conical surfaces do not mate exactly, nevertheless it has been found that they mate sufficiently well for the two parts to be substantially held in alignment.

The rubber bushing 22 is dimensioned so that when held by the torque rod end and axially uncompressed it can slide easily onto the spigot, and the cap can be easily inserted into it. However, when the spigot and cap are drawn together by nut 30b, the bushing 22 is axially compressed between the bearing surfaces 40 and 62 of the spigot and cap parts, and is thus also caused to be compressed between the cylindrical surface of the spigot and the internal surface of knuckle 20, to such a degree that the bushing does not normally slide relative to these surfaces, being sufficiently deformable to allow the normal movements in the suspension without sliding. However, unusual movements will allow the rubber to slip until it reaches a neutral position.

For replacement of the bushings of a torque rod, all that is required is the removal of nuts 30b holding the cap parts at each end of the torque rod, whereupon the rod and caps are removed, and the rod replaced with a new rod or with the same rod fitted with new bushings. There is sufficient spring in the rubber bushing for the spigot assembly to be tightened up completely at one end, and the other end of the torque rod can still be sprung onto its spigot. Preferably, however, the ends of the torque rod are placed on the respective spigots before any tightening takes place.

It will be seen that the spigot assembly can be used in many different situations.

Figure 1, in addition to showing the spigot assembly 24 attached to the chassis member 12, shows identical spigot assemblies which are attached to a vertical plate 70 projecting upwardly from the axle 10 and braced by gussets 72. Similar spigot assemblies can be used for locating the lower torque rods, although of course in this case the support 34 would have its axis normal to the base 32, rather than at an oblique angle.

WHAT WE CLAIM IS: 1. A spigot assembly for attaching a knuckle of a member of a vehicle to a relatively movable part of the vehicle via a bushing, said bushing having a bore and ends and being held within said knuckle, said spigot assembly comprising: a rigid metal spigot part having a base portion arranged, in use, to be rigidly secured to said vehicle part and a projection extending from said base, said projection having first tapered annular surface means facing axially outwardly of the projection and having a bore co-axial with said first annular surface means; a rigid metal capa part having second tapered annular surface means complementary to and engageable with that of said projection and having a bore co-axial with said annular surface means of the cap part; and fastening means receivable in said bores for fastening said spigot and cap parts together with said first and second tapered annular surface means engaged in mating relation with one another; said first and second tapered annular surface means being arranged to hold the cap part in co-axial alignment with the spigot part so long as the fastening means holds such annular surfaces in mating relation to one another, and wherein both said projection and said cap part further each include an outer surface

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. projection to an annular bearing surface 40 which surrounds the foot of the projection. The projection extends for a length slightly more than half the length of the bushing 22 of a torque rod end received thereon, and has at its outer end an axial recess largely defined by a frusto-conical surface 44 which diverges from the base of the recess and from an axial bore 46 within the projection. The bore 46 is designed to take a bolt 30', and the underside of the support 34 is provided with a triangular recess 34a, the form of which is shown in Figure 3, and the sides of which are designed to prevent rotation of the hexagonal head 30a of the bolt. The bolt is placed within the bore, as shown, before the part 26 is secured to a chassis member or like part, and is retained in the position shown by means of a locking ring 31 which engages in the recess of the projection near to its bottom. The cap part 28 is of hollow, cup-like form, having a projection with an outwardly facing frusto-conical surface engaging the surface 44 of the recess in the spigot part. The cap part also has a generally cylindrical surface 60 which forms a continuation of the surface of the projection 38, although being of slightly less length. This cylindrical surface is joined by a radius to an annular bearing surface 62 which faces the surface 40. The hollow interior of the cap part receives the screw threaded portion of bolt 30', and has a flat bottom area 64 engaged by a nut 30b on the bolt. During assembly of a suspension as illustrated in Figure 1, the spigot part is firstly fitted with the bolt 30', and the retaining ring 31, and is then bolted onto the respective chassis member 12. The spigot parts may also be made suitable for welding onto a chassis or other part. A torque rod 14 is then located on the projection of the spigot, as shown in Figure 2, and the cap part 28 then placed in position also as shown in Figure 2. The nut 30b is then put in place and tightened until the complementary frusto-conical surfaces of the spigot and cap parts are drawn tightly together. Although both the spigot and cap parts are in as-cast condition, so that the frusto-conical surfaces do not mate exactly, nevertheless it has been found that they mate sufficiently well for the two parts to be substantially held in alignment. The rubber bushing 22 is dimensioned so that when held by the torque rod end and axially uncompressed it can slide easily onto the spigot, and the cap can be easily inserted into it. However, when the spigot and cap are drawn together by nut 30b, the bushing 22 is axially compressed between the bearing surfaces 40 and 62 of the spigot and cap parts, and is thus also caused to be compressed between the cylindrical surface of the spigot and the internal surface of knuckle 20, to such a degree that the bushing does not normally slide relative to these surfaces, being sufficiently deformable to allow the normal movements in the suspension without sliding. However, unusual movements will allow the rubber to slip until it reaches a neutral position. For replacement of the bushings of a torque rod, all that is required is the removal of nuts 30b holding the cap parts at each end of the torque rod, whereupon the rod and caps are removed, and the rod replaced with a new rod or with the same rod fitted with new bushings. There is sufficient spring in the rubber bushing for the spigot assembly to be tightened up completely at one end, and the other end of the torque rod can still be sprung onto its spigot. Preferably, however, the ends of the torque rod are placed on the respective spigots before any tightening takes place. It will be seen that the spigot assembly can be used in many different situations. Figure 1, in addition to showing the spigot assembly 24 attached to the chassis member 12, shows identical spigot assemblies which are attached to a vertical plate 70 projecting upwardly from the axle 10 and braced by gussets 72. Similar spigot assemblies can be used for locating the lower torque rods, although of course in this case the support 34 would have its axis normal to the base 32, rather than at an oblique angle. WHAT WE CLAIM IS:

1. A spigot assembly for attaching a knuckle of a member of a vehicle to a relatively movable part of the vehicle via a bushing, said bushing having a bore and ends and being held within said knuckle, said spigot assembly comprising: a rigid metal spigot part having a base portion arranged, in use, to be rigidly secured to said vehicle part and a projection extending from said base, said projection having first tapered annular surface means facing axially outwardly of the projection and having a bore co-axial with said first annular surface means; a rigid metal capa part having second tapered annular surface means complementary to and engageable with that of said projection and having a bore co-axial with said annular surface means of the cap part; and fastening means receivable in said bores for fastening said spigot and cap parts together with said first and second tapered annular surface means engaged in mating relation with one another; said first and second tapered annular surface means being arranged to hold the cap part in co-axial alignment with the spigot part so long as the fastening means holds such annular surfaces in mating relation to one another, and wherein both said projection and said cap part further each include an outer surface

co-axial with their tapered annular surface means, each of said parts further having an annular flange extending outwardly of and co-axial with said outer surface and arranged so that, in use of the spigot assembly with said spigot and cap parts fastened together by said fastening means, said outer surfaces and annular flanges can engage the bore and ends respectively of the bushing held within said knuckle to provide locating means for said bushing.

2. A spigot assembly as claimed in claim 1 wherein each of the first and second annular tapered surface means lies in a frusto-conical surface co-axial with said projection and cap part bores thereby to stabilize the cap part relative to the spigot part under the influence of bending moments.

3. A spigot assembly as claimed in claim 2, wherein each of the first and second tapered annular surface means comprises a single frusto-conical surface.

4. A spigot assembly as claimed in claim 1 wherein said projection has a recess defined in part by said first tapered annular surface means; the bore of said cap part extends from the second tapered annular surface means of said cap part to a co-axial recess provided in said cap part; and said fastening means comprising a nut and a bolt, said bolt arranged to extend through said projection and cap part bores when said parts have their annular surface means engaged in mating relationship with one another; the said nut being receivable on said bolt within said recess of the cap part.

5. A spigot assembly as claimed in any one of claims 1-4 wherein said spigot and cap parts are cast parts in an as-cast condition.

6. A spigot assembly as claimed in claim 4, wherein the base of said spigot part is hollow and is provided with means for locating the head of the bolt to prevent rotation of said bolt.

7. A spigot assembly as claimed in claim 4, and further comprising a locking ring engaging a shank of said bolt within said recess of the projection to retain the bolt in the spigot part in the absence of said nut.

8. A spigot assembly for attaching a knuckle of a member of a vehicle to a relatively movable part of the vehicle substantially as hereinbefore described with reference to and as shown in the accompanying drawings.