AU784430B2 - Improvements in or relating to detachable couplings - Google Patents

Description

zi I t9ot ZU15Z tjj.- 130 -04-D-4100XIIJ 1-

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT

ORIGINAL

P100/001 I Regulation 3.2 Name of Applicant: Best Bars Limited Actual Inventors: MICHAEL JOHN PARKER Address for service in Australia: Ross Newnhatrn, Newniat Co PO Box 1325, Crows Nest New South Wales 1585, Australia Ph: 0064-9-358-0590 Fax: 0064-832 66670 Invention Title: IMPROVEMIENTS IN OR RELATING TO DETACHABLE COUPLINGS Thc following statemnent is a full description of this invenition, including the best method of performinig it known to us; Pauapp.doc 21/05 '02 TUE 07:31 [TX/RX NO 77821 LI I V/ LtJEJL V..O VJ1297.&Cdo 2 This invention relates to detachable or at least linearly adjustable mechanical couplings and more particularly to an anti vibration or rattle device for incorporation into such a coupling.

Often there is a need to provide a detachable mechanical coupling between two members.

particularly where the members are of a metallic nature and are parts of an apparatus such as vehicle vibration can occur between the two members. This can cause, inter alia, wear and tear as well as undesirable vibration or rattling noise. An object of this invention is to provide an anti-vibration or rattle device for utilisation with including incorporation into such a coupling. A suitable use for this invention is in conjunction with or incorporation into a detachable tow bar coupling such as described in our New Zealand Patent 231286.

According to a first embodiment of this invention there is provided a detachable mechanical coupling wherein an integral fastener-receiving element of a first coupling member is locatable between a pair of laterally spaced apart apertured shoulder elements projecting from a face of a second coupling member with the first coupling member seating on the face whereby a fastening bolt can be mounted in the apertures and through the fastenerreceiving element to detachably join the members together characterised in that a compressible bush is provided for mounting on a shank of the bolt between the shoulders and a pressure element is carried by the bolt to longitudinally impinge onto an end of the bush with tightening of the bolt to cause the bush to radially distort and dislodge the bolt and pressure element against their respective receiving elements and thus tend to impinge the coupling members together.

21/05 '02 TUE 07:31 [TX/RX NO 7782] Z±'I JL O I Zfzirl U .O 3 According to a second embodimaent of this invention there is provided a detachable coupling as described in the preceding paragraph wherein the pressure element forms an annular shoulder extending about the shank of the bolt.

According to a third embodiment of this invention there is provided a detachable coupling as described in the preceding paragraph wherein the pressure element is formed by a sleeve located on the shank of the bolt.

According to a fourth embodiment of this invention there is provided a detachable coupling as described in the second embodiment of the invention wherein the pressure element is formed by an integral shoulder or shoulders, as the case may be projecting from the either or both the nut or the head of the bolt.

According to a fifth embodiment of this invention there is provided a detachable coupling as described in any one of the four immxediately preceding paragraphs wherein the bush incorporates annular rigid elements at the ends thereof.

According to a sixth embodiment of this invention there is provided a fastener for a detachable mechanical coupling as described herein comprising a compressible bush locatable on a sbank of a coupling fastener bolt also supporting means to, in assembly, impinge longitudinally onto at least one end of the bush to cause the bush to radially distort and dislodge the bolt and pressure element against their respective receiving elements and thus tend to impinge the coupling members together.

In further describing the invention reference is made to the accompanying drawings of a piefeued eatbulixnni wherein; 21/05 '02 TUE 07:31 ITX/RX NO 7782] zv l VD. .70 11i22lLdO 4 Fig I is an exploded perspective view, and Fig. 2 is a plan view, partly in cross-section to assist clarity depicting the device in a.

coupled mode, and Fig. 3 is a side view again partly in cross-section to assist clarity and depicting the device in an assembled mode in readiness to receive the coupling bolt an associated collars.

A detachable mechanical coupling or mounting is provided between a first member 1 being a detachable element and a second permanently attached member 2 of a vehicle tow bar device. The detachable member 1 carries or is adapted to carry a conventional tow-ball at one end la and forming the opposing end incorporates a mounting coupling section lb preferably having an integral fastener-receiving element 11I preferably of tubular form thereon. With mounting the section lb of the detachable coupling member 1 is linearly presented to the second permanently fixed coupling member 2. In so doing the fastenerreceiving element I]I is aligned with apertuires 12 formed in laterally spaced apart shoulder forming elements 10 on the fixed member 2. The shoulder forming elements 10 project from a face 9 of the fixed member 2 on which the first member I seats when mounted thereon. Preferably the detachable member l and the fixed member 2 are coupled together by use of a mounting bolt 5 and associated nut 7 extending between the shoulders 10 and through the fastener-receiving element 11.

A compressible bush 3, made for example from a high compression rubber compound, is provided to locate closely about the shank of the mounting bolt 5. In assembly the bush 3 seats between the shank of the bolt 5 and the bore of the fastener-receiving element 11.

21/05 '02 TUE 07:31 [TX/RX NO 77821 ZI I rJzf IUOi Uj). S Preferably the bushi 3 is of a length substantially the same as that of the fastener-receiving element I11 and preferably both are a close fit between the shoulders 10 of the fixed member 2. Preferably load bearing rigid sections, such as metal collars 4, are provided, preferably integrally by suitable bonding, at each end of the bush 3. Preferably the external diameter of the bush 3 provides for a close fit within the bore of element I11 and to that end includes an elongate facet 1 la along the length thereof which in assembly matches and seats on the associated fare of that bore.

Preferably the mounting bolt 5 extends completely through the shoulders 10 and the associated fastening nut 7 is utilised to enable the bolt S to be tightened in conventional manner to couple the members I and 2 together. Protective caps 6 are preferably provided for the head of the bolt 5 and the nut 7. A pressure element 8 is provided to be carried by the fastening bolt 5 and with the tightening be longitudinally impinged onto at least one end of the bush 3, To that end, the diameter of the shank of the bolt 5 is such that the pressure element 8 can be located thereon and through the apertures 12 of shoulders 10. The pressure element S preferably forms an annular shaped shoulder exmending about the shank of the bolt 5 adjacent either or both the head thereof and the associated nut 7. The pressure element 8 may take the form, as depicted, of a separate sleeve or take the form of an integral projecting shoulder formed as part of either the head of the bolt 5 or the associated fastening nut 7.

With assembly the fastening bolt 5 is tightened and in so doing the pressure element(s) 8 are impinged onto the associated end(s) of the bush 3. The tightening will cause the bush to radially expand or distort. The distortion will cause the bolt 5 and associated pressure 21/05 '02 TUE 07:31 [TX/RX NO 77821 ZI I zrJrJL .3 04±J -04-s3_4L 001 f j IJtZ.doc 6 element(s)8 to. impart a dislodging action against the walls of the apertures 12.

Consequently this dislodging action is imparted between the detachable member 1 and the fixed member 2 tending to impinge them together and thus limit vibration therebetween.

Consequently it is envisaged that undesirable vibration generated noise of the coupling will be at least reduced if not eliminated.

21/05 '02 TUE 07:31 [TX/RX NO 7782]

Claims (8)

1. A detachable mechanical coupling wherein an integral fastener-receiving element of a first coupling member is locatable between a pair of laterally spaced apart apertured shoulder elements projecting from a face of a second coupling member with the first coupling member seating on the face whereby a fastening bolt can be mounted in the apertures and through the fastener-receiving element to detachably join the members together characterised in that a compressible bush is provided for mounting on a shank of the bolt between the shoulders and a pressure element is carried by the bolt to longitudinally impinge onto an end of the bush with tightening of the bolt to cause the bush to radially distort and dislodge the bolt and pressure element against their respective receiving elements and thus tend to impinge the coupling members together.

2. A detachable coupling as claimed in claim 1 wherein the pressure clement forms an annular shoulder extending about the shank of the bolt.

3. A detachable coupling as claimed in claim 1 or claim 2 wherein the pressure element is formed by a sleeve located on the shank of the bolt.

4. A detachable coupling as claimed in any one of the preceding claims wherein the pressure element is formed by an integral shoulder or shoulders, as the case may be projecting from the either or both the nut or the head of the bolt.

A detachable coupling as claimed in any one of the preceding claims wherein the bush incorporates annular rigid elements at the ends thereof. 21/05 '02 TUE 07:31 [TX/RX NO 7782] LI/ JJ/L UUL =r U-j, J ~ra j N1212.da 8

6. A fastener for a detachable mechanical coupling as described herein comprising a compressible bush locatable on a shank of a coupling fastener bolt also supporting means to, in assembly, impinge longitudinally onto at least one end of the bush to cause the bush to radially distort and dislodge the bolt and pressure element against their associated receiving elements and thus tend to impinge the coupling members together.

7. A detachable mechanical coupling substantially as herein described with reference to the accompanying drawings.

8. A fastener for a detachable mechanical coupling substantially as herein described with reference to the accompanying drawings. BEST S LIMITED By er Attorneys NEWN1HAM CO 21/05 '02 TUE 07:31 [TX/RX NO 7782]