GB835604A - Improvements in and relating to retractable undercarí¡í¡s for trailer vehicles - Google Patents

Abstract

835,604. Road vehicle undercarriages. BLACK, D. S. P., and GRANT, K. A. May 15, 1958 [May 29, 1957], No. 17013/57. Class 108(2) A trailer has support wheels 20 carried by legs 19 which are pivotally mounted at 18a so as to be retractable rearwardly (Fig. 4, not shown) when the trailer is in coupled position on the tractor. The legs 19 carry. auxiliary legs 21 which bear at their upper ends on a stop 11a in the event of the leep 19 failing to return to their loadbearing position, or in the event of failure of locking means. The stop lla is in the form of a circular channel section member which is carried by cross members 11, and to which is welded a turntable member 10. A lower turntable member 12 carries the pivot 18a and also stub axles 14 carrying rollers 15 which co-operate with ramps on the tractor during coupling up. A guide device 23 secured to each leg 21 comprises an inverted L-shaped track 24 closed at its upper end and open at its lower end. Pins 29 are carried by arms 27b which are rigid with a member 30, and also with arms 27 pivotally mounted on rearwardly extending arms 26 rigid with the member 12. A pair of springs 32 acts to draw the member 30 forwardly so that in the extended position of the wheels 20, the pins 29 engage the upper end of the track 24. This holds the arms 19 in extended position. A further locking action is provided by lugs 31 on the arms 27b engaging the tops of the respective guide devices 23. When the trailer is uncoupled from the tractor, the rearwardly extending trip guide (not shown) of the latter co-operates with a rubber roller 28 carried between the arms 27. This causes the arms 27 to swing backwards and the pins 29 are thus made to bear on the track 24 and retract the legs 19.