| 摘要 |
973,494. Change speed control: valves. BORG-WARNER CORPORATION. Feb. 22, 1961 [March 4, 1960], No. 26094/63. Divided out of 973,493. Headings F2D and F2V. A governor valve providing pressure variable in accordance with vehicle speed in a fluid pressure control system for an automobile change speed gear of Specification 973,493 has a three-stage action for extension of its speed range. The valve comprises radially bored casings 711, 712 fixed to a casing 710 keyed on a change speed gear output shaft 11. The casing 711 has an inlet (main line pressure) port 719, exhaust ports 721, 722 and an outlet port 720 connected to an inlet port 736 of the casing 712 which has an outlet (governor pressure) port 737 and exhaust ports 738, 739. A sleeve 714 having different sized lands 723, 724 slides within the casing 711. A centrifugal weight 715 piloted in the sleeve 714 acts thereon through a stem 716, a cap 717 and a spring 728. A piston 731 having different sized lands 733, 734 slides within the casing 712 and is urged outwardly by a spring 732 and centrifugal force. In operation, outward movement of the sleeve 714, acted on by the weight 715, admits main line pressure which then acts on the different lands 723, 724 to tend to move the sleeve inwardly to close the port 719 thereby providing an output pressure regulated as a function of output speed and shown in Fig. 2 by the line OA. When the cap 717 bottoms out against the casing 711 any increase in the centrifugal force acting on the weight 715 is no longer effective to move the sleeve 714, and the centrifugal force acting on the sleeve 714 itself continues to provide an output pressure regulated as a function of output speed and shown by the line AB. For all speeds lower than point B, the spring 732 and centrifugal force on the piston 731 act to provide a continuous communication between the inlet and outlet ports 736, 737 of the casing 712. However at point B the force due to pressure on the different lands 733, 734 tends to move the piston 731 inwardly to close the port 736 thereby providing an output pressure as shown by the line BC. Specification 973,495 also is referred to. |
