GB605034A - Improvements in or relating to power steering devices for tractor-trailor combinations - Google Patents

Abstract

605,034. Power steering. LETOURNEAU, Inc., R. G. Dec. 12, 1945, No. 33676. Convention date, Dec. 30, 1944. [Class 79 (v)] [Also in Group XXX] A power steering device for a tractor-trailer combination comprises a pair of members mounted together for relative rotation about a vertical axis one of which is rigidly connected to the trailer, the other of which is connected to the tractor in lateral tiltable relation thereto and driving means actuated by the tractor engine whereby the members may rotate relatively regardless of lateral tilt between the tractor and trailer. As shown the power steering device 7 is rigidly attached to the arm 8 of the trailer 9 and comprises two members, one of which is a king pin 16 bolted to a cylinder 11 which in turn is journalled at its ends in bearings 13 mounted in brackets 14 which are mounted rigidly on the platform 4, thus permitting lateral tilt. The second member consists of a body 17 mounted in bearings 18, 19 on the king-pin for movement thereabout, the body being connected to the draught arm 8 by bolts 23. The drive from the engine consists of a horizontal shaft 26 passing through the cylinder 11, geared to a vertical shaft 32 passing through the king pin 16. At the upper end of the shaft 32 is mounted a gear wheel 37, Fig. 3, which meshes with one of two intermeshing gear wheels 38, 39. Each of the latter gears have rotatably mounted on their shafts 40, 41 a smaller gear wheel 42, 43 which can be driven separately by the operation of hydraulic clutches 48, 49. Each of the smaller gears 43, 43 meshes continually with a gear wheel 44 which is mounted on a shaft 45 carrying at its lower end a pinion 52. This pinion meshes with a gear wheel 24 rigidly secured to the king pin 16. In operation one or the other of the gear wheels 42, 43 are clutched to drive the shaft 45 in the desired direction of rotation in which case the pinion 52 drives the gear wheel and hence turns the tractor about the axis of the pinion 52. A brake is fitted to one of the shafts 40, 41 to prevent relative rotation between the tractor and trailer when the combination is pursuing a straight course Cable winches 55, 56 are mounted for rotation over the housing 17 (see Group XXX).