GB846681A - Improvements in maximum-speed limiting devices for internal combustion engines - Google Patents

Abstract

846,681. Speed governors. SOC. INDUSTRIELLE DE BREVETS ET D'ETUDES S.I.B.E. Feb. 19, 1959 [April 24, 1958], No. 5794/59. Class 57. In speed-regulating devices for internalcombustion engines comprising an unbalanced throttle valve 2 arranged in the induction pipe 1 and urged towards the open position by elastic means against the action of the flow of gases in the pipe and/or the engine suction; the force exerted by the elastic means is varied to compensate for changes in ambient atmospheric pressure. The valve is rotatably mounted on a shaft 3 and urged towards its open position by a coil spring 8 tensioned between the valve and a sleeve 11 axially adjusted by a nut 13 screwed on a support 14, the sleeve and the nut having flat surfaces engaging corresponding surfaces on a cover 15. An aneroid capsule 16 housed in a cover 20 open to atmosphere through an aperture 21 is fixed at one end to the cover and at the other end to a rod 17 connected to a lever 18 fast with a pinion 19 engaging a rack 14a on the support 14. When the atmospheric pressure decreases the capsule extends and rotates the pinion anticlockwise, thus reducing the tension of the spring 8. Similarly, an increase in atmospheric pressure results in an increase in the tension of spring 8. The engine speed is thereby kept substantially constant irrespective of variations in atmospheric pressure. Pins 6 on the shaft 3 co-operating with abutments 7 on the valve 2 provide a lost-motion connection between the valve and the accelerator lever 5 secured to shaft 3. In a modification, Fig. 2 (not shown), the coil spring 8 is replaced by a flat spring whose flexibility is varied by movement of the capsule 16.