| 摘要 |
<p>1,012,059. Fluid-pressure brakes; valves. WESTINGHOUSE BREMSON-G.m.b.H. Oct. 23, 1962 [Nov. 4, 1961], No. 40049/62. Headings F2F and F2V. A variable load brake control valve comprises a differential piston 2, 3 including a diaphragm 3 arranged to bear on one of its sides in one extreme position against fixed radial ribs 7 provided in the housing 1 of the valv and in a second extreme position against radial ribs 6 fixed to the piston 2, the two sets of ribs being arranged to mesh together such as to form, between these two extreme positions, a variable effective area for the diaphragm. The chamber 1 of the valve is subjected to air from a reservoir via a brake valve (both not shown) and through a connection 19. Chamber II is open to atmosphere. The air pressure in chamber III is in communication with a connection 20 to the brake cylinders and is set in proportion to that in chamber I. The differential piston 2, 3 is provided with a double-seated valve member 5 which acts in conjunction with a hollow piston 9, the latter being arranged to act as a brake cylinder exhaust valve and also being connected to a vehicle load responsive mechanism formed by a lever 15 connected to the vehicle axle and having a cam means 14 adjustable to actuate a pivotally mounted rod 11 which acts on the hollow piston 9. At the end of the hollow piston 9 is a spring-biased differential piston 16 subjected to a main fluid pressure supply via communication 18 such that, upon a loss of pressure in the supply, the differential piston moves to close the exhaust valve.</p> |
