GB935901A - Improvements in or relating to levelling valve mechanisms - Google Patents

Abstract

935,901. Maintaining vehicle height constant. DUNLOP RUBBER CO. Ltd. Jan. 21, 1960 [Feb. 7, 1959], No. 4360/59. Class 108(2) A valve mechanism for maintaining the height of a vehicle constant comprises a casing 10, a port 17 communicating with one or more fluid springs, a port 15 connected to a source of fluid pressure, an exhaust port 16, an inlet valve 37 to connect the ports 15, 17, an exhaust valve 44 to connect the ports 16, 17, a pair of pressureresponsive devices, such as bellows 21, 22, each associated with one of the valves, and means 30 controlled by a member 35 responding to changes in vehicle height for adjusting the pressure on one or other of the bellows and thereby causing actuation of the corresponding valve. When vehicle height decreases the members 35 is rotated anti-clockwise by a lever and spring connection with the unsprung part of the vehicle to cause a resilient pad 31 to close a port 26 between the bellows 21 and the interior of the casing 10 which is at atmospheric pressure. Contraction of the bellows 21 now occurs by virtue of a connection through ducts 27 and a port 14 with a source of sub-atmospheric pressure so that the valve 37 is actuated by an arm 24 and a lever 43 to admit fluid to the spring until the body is restored to its original height. The valve 37 consists of two parts separated by a spring 39 and provided with rubber closure pads 40. The lever 43 lifts the right hand part from its seat by displacement of a tappet 41 to produce a pressure difference across the left hand part which is thus also lifted to open the part 15 leading to the supply of fluid under pressure. The exhaust valve 37 consists of a part 38A similar to one of the parts of the inlet valve and has a tappet 41A for direct engagement by an arm 25 on the bellows 22 when the vehicle height is increased.