Patent GB-620126-A (GB)
Title: Improvements in and connected with steering means of trailers, semi-trailers and like vehicles
IPC: B62D13/02
Filed: 1945-09-18
Abstract: 620,126. Steering motor vehicles. HARDMAN, L. W. Sept. 18, 1945, No. 24124. Convention date, June 16. [A Specification was laid open to inspection under Sect. 91 of the Acts, Jan. 30, 1946]. [Class 79 (v)] The body 42, Fig. 1, of a road vehicle is mounted on spaced bogies 41, 44 of which the forward bogie 41 is steerable and the after bogie is connected to the forward bogie by hydraulic means whereby it is constrained to move angularly in unison with the forward bogie up to a predetermined maximum position on each side of the normal and is held in that position while the angular movement of the front bogie is increased. The hydraulic means interconnecting the bogies comprises a ram.57, Fig. 3, slidable in a pair of opposed cylinders 58, situated at the front of the vehicle and connected by pipes 71, 72 to a similar pair of opposed cylinders 70, Fig. 8, situated at the rear of the vehicle and containing a reciprocatory ram 69. The ram 69 is operatively connected to the rear bogie by a pin 68 that is slidable in a bore in the ram and has a ball-shaped head received within a socket 67 on a plate 66 rigid with the rear bogie. The forward ram 57 is connected in similar manner by a ball-headed pin 56 to a block 51 normally situated in a recess 49 in the periphery of a ring 47 rigid with the front bogie 41. Steering movement of the bogie causes the ring 47 to rotate in one direction or the other relatively to a plate 48 carried by the body and shaped to correspond with the periphery of the ring. Continued rotation of the ring causes a post 54 on the block 51 to enter a slot 60 in one of a pair of pivoted transfer arms 63, urged to the normal position shown by springs 64. At the same time, a pin 62 on the ring 47 enters a guide groove 61 in the transfer lever, which is rocked to the left and causes the block 51 to enter one of a pair of recesses 50 in the plate 48. the block is held in this position by the periphery of-thering as the steering movement of the bogie is increased with the result that the rams 57, 69 remain stationary and the rear bogie ceases to move in unison with the front-bogie. The pipes 71, 72 of the hydraulic system may all lead to a common control valve adjustable from the normal position, in which the rear bogie is caused to rotate in the opposite sense to the front bogie, to two other positions, in the first of which the rear bogie is locked and in the second it rotates in the same sense as the front bogie. The Specification, as open to inspection under Sect. 91, comprises also a construction of trailer comprising two turn-tables 20, Fig. 2 (Cancelled), each mounted on a bogie 10 and connected together primarily by the load to be carried and secondarily by a a skeleton chassis 22, 24, 22, Associated with each bogie is a pair of hydraulic cylinders 28 within which slide hollow rams 27 pivoted to the chassis. The interior of the rams is connected by pipes 31 to cause the rear bogie to be steered in unison with the front bogie, but in the opposite sense. In this construction also, a valve may be provided to change the effect of the system as described above. This subject-matter does not appear in the Specification as accepted.