AS 4177.1-1994

1 - AS 4177.1-1994 CARAVAN AND LIGHT TRAILER TOWING COMPONENTS - TOWBARS AND TOWING BRACKETS
4 - PREFACE
4 - CONTENTS
5 - 1 SCOPE
5 - 2 REFERENCED DOCUMENTS
5 - 3 DEFINITIONS
5 - 3.1 Aggregate trailer mass
5 - 3.2 Ball coupling
5 - 3.3 Coupling
5 - 3.4 Coupling body
5 - 3.5 Drawbar
5 - 3.6 Gross trailer mass
6 - 3.7 Light trailer (TB)
6 - 3.8 Load distributing hitch
6 - 3.9 Rated towbar capacity
6 - 3.10 Shall
6 - 3.11 Shank-type towball
6 - 3.12 Should
6 - 3.13 Towball
6 - 3.14 Towbar
6 - 3.15 Towing lug
6 - 3.16 Vehicle
6 - 3.17 Very light trailer (TA)
6 - 4 DESIGN AND CONSTRUCTION
6 - 4.1 Attachment to vehicle
6 - 4.2 Towball
6 - 4.2.1 General
6 - 4.2.2 Height of towball
8 - 4.3 Towing lug hole dimensions
8 - 4.4 Provision for safety chain connections
8 - 4.5 Rated towbar capacity
8 - 5 PERFORMANCE REQUIREMENTS
8 - 5.1 General
8 - 5.2 Static strength test
8 - 5.3 Static testing of safety chain connection points
8 - 5.3.1 Strength requirements
9 - 5.4 Dynamic strength test
9 - 6 MARKING
10 - APPENDIX A - STATIC STRENGTH TEST
10 - A1 SCOPE
10 - A2 PRINCIPLE
10 - A3 APPARATUS
10 - A4 PROCEDURE
11 - A5 REPORT
12 - APPENDIX B - STATIC STRENGTH TEST OF SAFETY CHAIN CONNECTIONS
12 - B1 SCOPE
12 - B2 PRINCIPLE
12 - B3 APPARATUS
12 - B4 PROCEDURE
12 - B5 REPORT
13 - APPENDIX C - DYNAMIC STRENGTH TEST
13 - C1 SCOPE
13 - C2 PRINCIPLE
13 - C3 APPARATUS
13 - C4 PROCEDURE
13 - C5 REPORT

Specifies design and installation dimensions of a shank-type 50 mm towball on a towbar, marking requirements for towbars used on passenger cars (including forward control passenger vehicles and off-road passenger vehicles), light goods vehicles, and light omnibuses intended for towing of caravans and trailers of up to 3.5 t aggregate trailer mass. Describes static tests for longitudinal and vertical loading in tension and compression and for transverse load, and a dynamic test.

This Standard specifies requirements for towbars and towing brackets suitable for use with 50 mm towballs. The towbars are intended for towing very light and light trailers of up to 3.5 t aggregate trailer mass, in normal use on sealed and unsealed roads.NOTES:1 Towballs are specified in AS 4177.2, and their corresponding coupling bodies in AS 4177.3.2 Requirements for off-road applications are beyond the scope of this Standard.3 Light trailers include caravans, boat trailers, horse floats and other towable vehicles.4 Requirements for load-distributing hitches are not included in this Standard.5 Towbars should not be used for other than their intended purpose of towing.

First published as part of AS D18-1968.
Revised and redesignated in part as AS 4177.1-1994.