Patent GB-471886-A (GB)
Title: Reverse steering gear for two-wheel trailing vehicles
IPC: B62D13/04
Filed: 1936-02-05
Abstract: 471,886. Steering and braking trailer vehicles. NEW, A. W. S., and ASPEEK, R. J. Feb. 5, 1936, No. 28048/35. [Class 79 (v)] [Also in Group XXXIV] Steering - gear for two - wheeled trailer vehicles in which the wheels are mounted on stub axles connected together by steering arms 12 and a track rod 13, comprises a control member 26 pivoted at one end to a steering arm 25 and slidablymounted at the other end on an arm 24 forming an horizontal extension of the vertical coupling pivot 22 about which the trailer swings, the forward end of said control member being capable of being located in either of two positions on said arm, one of which coincides with the coupling pivot 22, to provide for the automatic steering of the trailer according to whether it is travelling backwards or forwards. In the construction shown, the trailer frame 17 is pivoted on the vertical axis 22 of a coupling rod 20 slidably-mounted in bearings 21 on the tractor and controlled by a spring 23. The forward end of the steering control member 26 is provided with a sleeve 28 sliding on the arm 24 and held by locking means 29 either in the position shown in broken lines in Fig. 2 for forward steering, or in the position shown in full lines for travelling backwards. The position of the member 26 may be adjusted directly by hand or from any desired part of the tractor. The arm 24 is curved to an arc having its centre at the other end of the member 26. Means may be provided to prevent the trailer being drawn forwardly when the control member 26 is in the reverse travel position. Such means may comprise pawls controlled by the member 26 and acting on ratchet wheels fixed to the trailer wheels so as to prevent forward movement thereof except when the control member is set for forward travel. The sliding movement of the coupling rod 20 on the tractor is utilized to apply the trailer brakes when the trailer overruns the tractor, and means are provided whereby the brakes are rendered inoperative when the steering control member 26 is set for rearward travel. The trailer brakes are applied by arms 16 connected to cables 36 which pass over pulleys 33, carried by levers 30 pivoted at 32 to the frame 17, and pulleys 38, their other ends being fastened at 39 to the steering control member 26. The upper ends of the levers 30 are connected together by a bar 31 engaged by a hook 35 fixed. to the tractor. Thus, when the trailer overruns the tractor the frame 17 compresses the spring 23 and moves forwardly relatively to the tractor thereby rocking the levers 30 to pull on the cables 36.. The cables are so adjusted that when the control member 26 is in the forward travel position with its forward end over the pivot 22 there is no slack in the cables while the tractor is pulling the trailer, but when the trailer overruns the tractor the brakes are applied by the rocking of the levers 30. When the steering control member 26 is moved to the reverse travel position shown, the movement of the cable anchorage 39 is sufficient to slacken the cables to such an extent that the brakes will not be applied when the levers 30 are rocked by the backward movement of the tractor.