| 摘要 |
<p>993,102. Change-speed control. FORD MOTOR CO. Ltd. Jan. 9, 1964 [Feb. 20, 1963], No. 974/64. Heading F2D. In an automatic change-speed vehicle transmission controlled by fluid-pressure engaged clutches and brakes the rate of increase in pressure in an engaging line 388 is controlled by a rate-control valve having a piston 396 controlling an exhaust port 400 under the opposing influences of upwardly and directly acting line pressure 388 and a downwardly acting spring together with line pressure reaching the upper piston face through a restrictor 404. The upper face also communicates with a spring-loaded accumulator piston 410. When the line 388 is pressurized to engage its clutch or brake, the restrictor 404 causes a pressure drop across it and allows upward force on the exhaust piston 396 to predominate and open the exhaust port 400, thus limiting initial engaging pressure. Increased engaging pressure compresses the accumulator spring and allows downward force to increase, regulating the exhaust opening to produce the required engaging rate and finally closing it entirely when flow through the restrictor ceases, and the accumulator spring is fully compressed.</p> |
