| 摘要 |
<p>836,166. Change-speed control. GENERAL MOTORS CORPORATION. Oct. 2, 1957 [Oct. 29, 1956], No. 30830/57. Class 80 (2). [Also in Group XXIX] Upon depressing a motor vehicle accelerator pedal 34, a plunger 26 moves a metering valve closure 26 through a spring 30 whereby an inlet 18 is placed in communication with an outlet 24, which latter is connected via a restriction 41 with a space behind the right-hand end of the closure that is in series with a chamber 38 in which is a fixed or adjustable spirally-wound bimetallic thermal-element 50 having an extension 54 engaging the righthand end of the closure 26. The fluid in chamber 38 urges the closure against the spring 30 until the inlet 18 is blocked and, if the pressure is great enough an exhaust port 22 is opened, otherwise both the inlet 18 and port 22 remains closed until the pressure falls and the inlet is reopened. If the fluid is cold, the element 50 also loads the closure 26 against the spring 30; as the fluid temperature rises this bias is reduced until at a given temperature it is completely removed. The pressure in the outlet 24, which is determined by the resultant of the force of spring 30 and the opposing forces of the fluid in chamber 38 and the element 50, acts upon another valve, not shown, in opposition to a speed-responsive pressure, the other valve controlling the servomotor of a step-ratio variable-speed transmission mechanism, not shown. The inner end of the element may either be positioned in a slot 48 incorporated in a post 46 attached to the valve body or in frictional engagement with the post. The spiral element 50 may be replaced by one of hairpin type.</p> |
