AU2008202797B2

AU2008202797B2 - A vehicle support arm assembly

Info

Publication number: AU2008202797B2
Application number: AU2008202797A
Authority: AU
Inventors: Michael Robert Hayes
Original assignee: Individual
Current assignee: Individual
Priority date: 2007-08-24
Filing date: 2008-06-25
Publication date: 2012-05-03
Anticipated expiration: 2028-06-25
Also published as: AU2012203220B2; AU2010100451A4; AU2012203220A1; AU2008202797A1; AU2010100451B4

Abstract

An automobile generally includes a chassis and a differential assembly for driving a pair of wheels. The present invention generally relates to a support arm assembly for supporting the differential assembly relative to the chassis. The support arm assembly includes a support arm for extending from the chassis. A mounting bracket mean can be mounted relative to an axle of the differential assembly. Coupling means is provided for resiliently coupling the support arm relative to the mounting bracket means. The support arm assembly is a useful expedient for twisting the differential assembly in use. s-~/

Description

AUSTRALIA PATENTS ACT 1990 COMPLETE SPECIFICATION STANDARD PATENT A VEHICLE SUPPORT ARM ASSEMBLY The following statement is a full description of this invention including the best method of performing it known to me: I A VEHICLE SUPPORT ARM ASSEMBLY TECHNICAL FIELD 5 The present invention relates to a support arm assembly for supporting a vehicle differential assembly relative to a vehicle chassis. The present invention has particular, although not exclusive application to four-wheel drive (4WD) vehicles. 10 BACKGROUND The reference to any prior art in this specification is not, and should not be taken as an acknowledgement or any form of suggestion that the prior art forms part of the common general knowledge. 15 Figure 1 shows a known support arm 2 (also called a "radius arm") for supporting a vehicle differential assembly 4 (Figure 2). In practice, a like pair of support arms 2 supports the differential assembly 4 on either side of the vehicle differential (not shown) which, in turn, drives a pair of wheels. 20 The doglegged support arm 2 is elongate and includes a threaded shaft 6 at one end for fastening the arm to the vehicle chassis (not shown) using a complementary fastening nut. The support arm 2 defines two apertures 8a,b at the other end which facilitate mounting to the differential assembly 4 as 25 explained below. Referring to Figure 2, a support arm assembly 10 including the support arm 2 is used to support the vehicle differential assembly 4 relative to the vehicle chassis. The support arm assembly 10 further includes a pair of couplers 30 12a,b force fitted within respective apertures 8a,b. The couplers 12a,b resiliently couple the support arm 2 to a pair of opposite mounting lug sets 14a,b of the differential assembly 4.

2 Retuning to Figure 1, each coupler 12 includes a resilient rubber bushing 16 for being received in a corresponding aperture 8 defined in the arm 2. Each coupler 12 further includes a rigid tubular core 18 fitted within the bushing 16 and for receiving the shaft of a respective fastener. The fastener is in the form 5 of a threaded nut and bolt assembly 20 (see Figure 2). Returning to Figure 2, each mounting lug set 14 includes a pair of parallel plate-like mounting lugs 22. In use, the support arm assembly 10 is located between the mounting lug sets 14a,b so that coupler 12a is between one pair 10 of mounting lugs 22a,22b and coupler 12b is between the other pair of mounting lugs 22c,22d. The tubular cores 18 of the couplers 12 are aligned with mounting holes defined in the lugs 22. The shafts of the nut and bolt assemblies 20 pass through the mounting holes and the tubular cores 18. 15 The foregoing arrangement of Figure 2 is suitable for use in a four wheel drive (4WD) vehicle. As the 4WD vehicle traverses uneven terrain, the differential assembly 4 can move relative to the support arm 2 (and therefore the vehicle chassis) owing to the resilience of the couplers 12a,b. Embodiments of the present invention provide an alternative support arm assembly whereby the 20 degree of movement of the differential assembly 4 relative to the support arm 2 can be increased. SUMMARY OF THE INVENTION 25 According to one aspect of the present invention, there is provided a vehicle including: a chassis; a differential assembly for driving a pair of wheels; and two support arm assemblies for supporting either side of the differential 30 assembly relative to the chassis, one of the support arm assemblies fixedly supporting the differential assembly relative to the chassis, the other support arm assembly including: a support arm for extending from the chassis and for supporting resilient coupling means; and 3 mounting bracket means for mounting to the differential assembly and resilient coupling means so as to facilitate axial twisting of the differential assembly. 5 The support arm may be elongate, and include fastening means at one end for fastening the arm to the chassis. The support arm may define two apertures at the other end. The apertures may be of different size. 10 The mounting bracket means may include a pair of mounting brackets for mounting to the differential assembly. Each mounting bracket may be shaped to form a cradle for cradling the differential assembly. Each mounting bracket may define a pair of holes which can align with corresponding holes of mounting lug means of the differential assembly. The support arm assembly 15 may further include a spacer for being fastened between the mounting brackets. Preferably, the mounting bracket means can be mounted to a pair of opposite mounting lug means of the differential assembly. Each mounting lug means 20 may include a pair of parallel mounting lugs. The mounting bracket means may be received between the mounting lugs. The mounting bracket means may be mounted to an axle assembly of the differential assembly. The coupling means may include two resilient bushings for being received in 25 respective apertures defined in the arm. The coupling means may further include a pair of rigid tubes fitted within respective bushings and for receiving shafts of respective fasteners. The coupling means may include the fasteners. According to another aspect of the present invention, there is provided a 30 method for mounting a first support arm assembly to support a vehicle differential assembly relative to a vehicle chassis, a second support arm assembly fixedly supporting the differential assembly relative to the chassis, the method including the steps of: 4 mounting a support arm of the first support arm assembly to extend from the chassis; mounting bracket means of the first support arm assembly to the differential assembly; and 5 resiliently coupling the support arm relative to the mounting bracket means so as to facilitate axial twisting of the differential assembly. BRIEF DESCRIPTION OF THE DRAWINGS 10 Preferred features, embodiments and variations of the invention may be discerned from the following Detailed Description which provides sufficient information for those skilled in the art to perform the invention. The Detailed Description is not to be regarded as limiting the scope of the preceding 15 Summary of the Invention in any way. The Detailed Description will make reference to a number of drawings as follows: Figure 1 is a perspective view showing a vehicle support arm according to the prior art; 20 Figure 2 is an upper perspective view showing the support arm of Figure 1 supporting a vehicle differential assembly according to the prior art; Figure 3 is a perspective view showing an unassembled support arm 25 assembly in accordance with an embodiment of the present invention; Figure 4 is a perspective view of the support arm assembly of Figure 3; and Figure 5 is an upper perspective view showing the support arm assembly of 30 Figures 3 and 4 supporting a vehicle differential assembly. DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 5 The use of any reference numerals below which have also previously been used, refer to like features previously described. According to an embodiment of the present invention, there is provided an 5 unassembled support arm assembly 30 as shown in Figure 3. The support arm assembly 30 is suitable for supporting a vehicle differential assembly 4 (see Figure 5) relative to a vehicle chassis (not shown). The support arm assembly 30 includes a support arm 32 for rigidly mounting to extend from the chassis. The support arm assembly 30 further includes a pair of mounting 10 brackets 34a,34b for rigidly mounting to the differential assembly 4. A pair of couplers 12a,12b are also provided for resiliently coupling the support arm 32 relative to the mounting brackets 34a,34b. A detailed description of the support arm assembly 30 is provided below. 15 Turing firstly to Figure 3, the elongate support arm 30 is bowed and includes a threaded shaft 36 at one end for fastening the arm 30 to the chassis using a complementary fastening nut (not shown). The support arm 30 defines two apertures 38a,b at the other end which are located in close proximity to each other so that, in use, they are both located on the same side of the differential 20 assembly 4. The endmost aperture 38b is of smaller size than the innermost aperture 38a. Each coupler 12 includes a resilient outer rubber bushing for being received in a respective aperture 38 defined in the arm 32. Each coupler 12 further 25 includes a rigid metal tube fitted within the bushing and for receiving the shaft of a respective bolt. In use, the couplers 12a,b are force fitted within respective apertures 38a,b. Each mounting bracket 34 is generally "L-shaped" to form a cradle for passing 30 under and cradling the differential assembly 4. Each mounting bracket 34 defines a triplet of holes 40. For each bracket 34, one pair of the holes 40 can align with corresponding holes of mounting lugs 22 of the differential assembly 4 (Figure 5) and another pair of the holes 40 can align with corresponding metal tube cores of the couplers 12. 35 6 The support arm assembly 30 further includes a rigid tubular spacer 42 for being fastened between the mounting brackets 34a,b in the location shown in Figure 4. Returning to Figure 3, a triplet of threaded bolts 44 are provided for passing through holes 40 of the mounting brackets 34a,34b. A triplet of 5 complementary threaded fastening nuts 46 are provided for engaging with the bolts 44 to hold the support arm assembly 30 together as shown in Figure 5. Turning to Figure 5, the differential assembly 4 includes a pair of opposite mounting lug sets 14a,b. Lug set 14a includes a pair of parallel mounting lugs 10 22a,22b whereas lug set 14b includes a pair of parallel mounting lugs 22c,22d. Each mounting lug set 14 defines a pair of aligned holes (i.e. one in each lug 22) through which the shaft of a bolt 44 can pass. In use, the support arm assembly 30 shown in Figure 4 is located between the 15 parallel mounting lugs 22 of the mounting lug sets 14a,b as shown in Figure 5. The triplet of bolts 44 (and nuts 46) is then used to fasten the support arm assembly 30 to the differential assembly 4. One of the bolts 44 passes through the lug 22a, mounting bracket 34a, coupler 12a, mounting bracket 34b and then lug 22b. Another one of the bolts 44 passes through mounting 20 bracket 34a, coupler 12b and then mounting bracket 34b. The final bolt 44 passes through the lug 22c, mounting bracket 34a, spacer 42, mounting bracket 34b and then lug 22d. Mounting bracket 34a is rigidly mounted to lugs 22a and 22c whereas 25 mounting bracket 34b is rigidly mounted to lugs 22b and 22d. The fastening joints about the couplers 12a,b are resilient whereby the couplers 12a,b resiliently couple the support arm 32 (fixed to the chassis) relative to the mounting brackets 34 (fixed to the differential assembly 4). The degree of movement of the differential assembly 4 relative to the support arm 32 is 30 greater than that of the differential assembly 4 relative to the support arm 2 previously described in the background. In practice, the applicant has found that having a pair of support arm assemblies support the differential assembly 4 on either side of the vehicle 7 differential (not shown) yields desirable results, when the support arm assembly 10 is provided on the driver side of the vehicle and the support arm assembly 30 is provided on the passenger side of the vehicle. In this manner, the differential assembly 4 is prone to axial twist in use. 5 Referring to Figure 5, the differential assembly 4 further includes a tubular axle 50 from which the opposite mounting lug sets 14a,b outwardly extend. The axle 50 is cradled by the brackets 34a,b and extends from the differential. A suspension seat 52 is located on top of the differential assembly 4 and, in 10 use, supports the wheel suspension system. A drive shaft (not shown) extends from the differential within the tubular axle 50 and terminates in an external wheel mounting plate 54 to which one of the vehicle wheels can be mounted. 15 In practice, the support arm assembly 30 can be retrofitted to a vehicle in place of the support arm assembly 10. Firstly, the support arm assembly 10 is removed from the vehicle. A retro-fit method for mounting the support arm assembly 30 to support the 20 vehicle differential assembly 4 relative to the vehicle chassis is now described. The method includes the steps of: (1) mounting the support arm 32 to extend from the chassis; (2) mounting the brackets 34a,b to the mounting lug sets 14a,b of the differential assembly 4; and (3) resiliently coupling the support arm 32 relative to the mounting brackets 34a,b using the couplers 12a,12b. 25 The foregoing steps can be performed in any order. A person skilled in the art will appreciate that many embodiments and variations can be made without departing from the ambit of the present invention. 30 In the preferred embodiment, the brackets 34a,b were mounted within the confines of the lugs 22. In an alternative embodiment, the brackets 34a,b can be mounted to the outside of the lugs 22 so that the lugs 22 are located between the brackets 34a,b.

8 In compliance with the statute, the invention has been described in language more or less specific to structural or methodical features. It is to be understood that the invention is not limited to specific features shown or 5 described since the means herein described comprises preferred forms of putting the invention into effect. The invention is, therefore, claimed in any of its forms or modifications within the proper scope of the appended claims appropriately interpreted by those skilled in the art.

Claims

1. A vehicle including: a chassis; a differential assembly for driving a pair of wheels; and two support arm assemblies for supporting either side of the differential assembly relative to the chassis, one of the support arm assemblies fixedly supporting the differential assembly relative to the chassis, the other support arm assembly including: a support arm for extending from the chassis and for supporting resilient coupling means; and mounting bracket means for mounting to the differential assembly and resilient coupling means so as to facilitate axial twisting of the differential assembly.

2. A vehicle as claimed in claim 1, wherein the support arm is elongate, and includes fastening means at one end for fastening the arm to the chassis.

3. A vehicle as claimed in claim 2, wherein the support arm defines two apertures at the other end.

4. A vehicle as claimed in claim 3, wherein the apertures are of different size.

5. A vehicle as claimed in any one of the preceding claims, wherein the mounting bracket means includes a pair of mounting brackets for mounting to the differential assembly.

6. A vehicle as claimed in claim 5, wherein each mounting bracket is shaped to form a cradle for cradling the differential assembly. 10

7. A vehicle as claimed in claim 5 or claim 6, wherein each mounting bracket defines a pair of holes which can align with corresponding holes of mounting lug means of the differential assembly.

8. A vehicle as claimed in any one of claims 5 to 7, further including a spacer for being fastened between the mounting brackets.

9. A vehicle as claimed in any one of the preceding claims, wherein the mounting bracket means can be mounted to a pair of opposite mounting lug means of the differential assembly.

10. A vehicle as claimed in claim 9, wherein each mounting lug means includes a pair of parallel mounting lugs.

11. A vehicle as claimed in claim 10, wherein the mounting bracket means can be received between the mounting lugs.

12. A vehicle as claimed in claim 1, wherein the mounting bracket means can be mounted to an axle assembly of the differential assembly.

13. A vehicle as claimed in any one of the preceding claims, wherein the coupling means includes two resilient bushings for being received in respective apertures defined in the arm.

14. A vehicle as claimed in claim 13, wherein the coupling means further includes a pair of rigid tubes fitted within respective bushings and for receiving shafts of respective fasteners.

15. A vehicle as claimed in claim 14, wherein the coupling means includes the fasteners. 11

16. A method for mounting a first support arm assembly to support a vehicle differential assembly relative to a vehicle chassis, a second support arm assembly fixedly supporting the differential assembly relative to the chassis, the method including the steps of: mounting a support arm of the first support arm assembly to extend from the chassis; mounting bracket means of the first support arm assembly to the differential assembly; and resiliently coupling the support arm relative to the mounting bracket means so as to facilitate axial twisting of the differential assembly.