GB1144342A - Improvements relating to the vibration testing of vehicle suspensions - Google Patents

Abstract

1,144,342. Testing vehicle suspensions; bearings. FAIREY SURVEYS Ltd. 20 May, 1966 [24 Feb., 1965], No. 8001/65. Headings F2A and F2S. [Also in Division G3] An installation for testing the suspension system of a road vehicle of the kind having at least one pair of road wheels mounted in positions spaced apart, one on either side of the vehicle, comprises, for each road wheel of the vehicle, a separate hydraulic vibration generator 10 each of which has a vertically movable jack plunger 13 with a table 14 upon which rests a horizontally movable wheel support platform 15, the vibration generators being mounted on a common fixed base 12, and means for driving the vibration generators independently of one another to apply to each road wheel a predetermined vertical vibration pattern, an antifriction bearing being incorporated in each vibration generator to allow relative movement between each wheel support and the fixed base in a horizontal direction parallel to the axis of the associated road wheel. Horizontal vibrations of the platform 15 are damped by an hydraulic piston and cylinder damper unit 20 having a damping control valve 25. The unit 20 may alternatively be employed as a vibration generator to impart horizontal vibrations 18 to a wheel 16. As shown, the platform 15 is supported by a ball or roller bearing 17. Alternatively, an hydraulic fluid bearing, Fig. 2 (not shown), may be interposed between the platform (30) and the jack table (31), recesses (32) in the underface (33) of the platform (30) being fed with pressure fluid delivered to a passageway (34) and one or more drain channels (36) being formed in the upper face of the table (31). The table (30) is also provided with a damper (20), and, alternatively, it may be supported by a pneumatic bearing. In a modification, a hydrostatic fluid bearing, Fig. 6, comprises a circular jack table 41 which is accommodated in a cylindrical recess 45 in a platform 40 formed by a flanged upper plate 42 bolted to a lower plate 44, an extension 48 of the jack plunger 13 passing through an aperture 49 in the lower plate 44 and through an oil sump 50. Four circumferentially-spaced, arcuate grooves 60 are formed in each bearing face 57, 58 and a separate oil passageway 62, formed in the respective plate 42 or 44 and provided with a flow restrictor 70, leads into each of the arcuate grooves 60 and is supplied with pressurized hydraulic fluid from a network of oil pipes (65), (66) having supply pipes (67), Fig. 4 (not shown). A branch passageway 76 extends from each passageway 63 and is provided with a nipple 74 for the application of a pressure gauge. One, or more, horizontal dampers, or vibrators, can be applied to each wheel support platform. A tapedriven control system for the installation of Fig. 1 is described (see Division G3).