Patent GB-276038-A (GB)
Title: Improvements in or relating to vehicles for service on roads and rails
IPC: B62D1/26
Filed: 1926-02-23
Abstract: 276,038. Roadrails, Ltd., and Roberts, J. Feb. 23, 1926. Steering road vehicles by rails.-A road vehicle or tractor is automatically steered by a rail bogie, the two vehicles being connected by a universal joint or like connection the two members of which can perform relative vertical movements, one being pivoted and the other slidable on its vehicle and adapted to transmit its displacements to the steering-gear of the road vehicle. In the construction shown in Fig. 15, a shaft B is pivoted on the rail bogie B and carries an arm C<1> sliding in a block C<2> which slides on a transverse rod D on the road vehicle A and operates the track-rod H coupling the stub-axles thereof by means of a lever E pivoted at F. Thus transverse movement of the rail bogie rotates the lever E and steers the road vehicle. In the construction shown in Fig. 17 a ball C<3> carried by the rail bogie B can slide vertically in a block C' sliding transversely in guides A<2> on the road vehicle A, the trackrod H being operated as before by a lever from. the block C'. Part of the weight of the road vehicle may be transferred to the rail bogie by means of a spring K. Modifications are described in which (1) a ball member, fitting within a socket on the road vehicle, is slidably carried on the rail bogie, and this sliding movement acts on rack-and-pinion gear to rotate a shaft which passes through the ball member and operates the steering-gear of the road vehicle: (2) a member, sliding under spring control on the truck-rod H, carries a depending arm which passes freely through a hole in a member fixed on the rail bogie; and (3) a vertical arm fixed on the bogie slides in a socket suspended by means of ropes which pass over pulleys on the road vehicle and are connected to the steering gear thereof. For steering a road vehicle in either direction of travel a rail bogie is provided at each end and connected by one of the before-mentioned universal connections to the steering-gear, the bogie which is leading at any time being the only one operative. In the construction shown in Fig. 3 the two universal connections C, c, each connected to a bogie (not shown), operate levers E, e connected to the steering track-rod H. The pivots 7, 8 of the levers E, e work in curved slots 9, 10 formed in pivoted arms 11, 12 which are so connected together by a link 13 that they are always substantially at right-angles to each other. In the position shown the connection C can operate the steering-gear through the lever E but movement of the connection e has no effect, the pivot 8 of the lever c moving idly in the slot 10. The link 13 is connected to the reversing gear of the tractor so that when the gear is changed the bogie which now becomes the leading bogie is made operative and the other one inoperative. In a modification for forward and reverse running, both pairs of wheels are steerable, each pair being controlled by a rail bogie. and that pair being locked which is the rear pair at any time. The steering of a road vehicle may be effected from outside by the bogie of a rail truck coupled to the road vehicle, this being effected by a steering arm attached to the bogie and detachably connected to the universal joint connection between the two vehicles. This steering arm may be fixed to the bogie or may be geared thereto for the purpose of locating the path actually travelled by the road vehicle with reference to that taken by the rail bogie. In cases where the tractor has a very long wheel-base or has to run on very sharp curves the rail bogie so acts on the steering-gear that the rear wheels of the tractor are brought towards the centre of the curve to avoid running the front steering-wheels on to the rail track. Manual means mav be provided for temporarily acting on the steering- gear so as to cause the road vehicle to run on a track having its centre line displaced from that of the rail track. According to the Provisional Specification rotary movements of the rail bogie about its vertical axis may be utilized to steer the road vehicle. Specification 114,880 is referred to.