| 摘要 |
1,096,656. Fluid-pressure brakes; valves. H. TEVES, E. A. TEVES and M. TAUSEND, [trading as ALFRED TEVES MASCHINENUND ARMATURENFABRIK KOMM. GES.]. Sept. 8, 1965 [Dec. 8, 1964], No. 38364/65. Headings F2F and F2V. A pressure-reducing valve for insertion in an hydraulic system between a master cylinder and rear wheel brake cylinders of a vehicle is of the kind employing a differential piston 5 operating in a stepped bore 4 of a casing 1 having an inlet 2 and outlet 3, a passage 10 by-passing the piston being closable by a poppet valve 6 acted on by a valve spring 19 in the closing direction, but being normally held open, due to the action of adjustable spring 24, by abutment of a pin 18 of the poppet valve with a fixed abutment, the invention being characterized by the provision of a resilient block 28, e.g. of rubber, which is secured to the casing end wall for abutment by the pin 18 and also by the adjacent end of the piston, this resulting in a modified operation of the valve, the usual hysteresis, caused by the returning fluid having to overcome the valve spring 19 during brake release, being thereby obviated. In operation, as master cylinder pressure rises above the " changeover " point, at which the piston moves to the right to close the valve, output pressure rises at a reduced rate as determined by the relative piston areas, but this is modified by the action of the block to give further reduction of the rate as pressure increases, the resilience of the block overcoming valve spring 19 on brake release. |
