GB443617A - Control mechanism particularly adapted to operate the clutch and brakes of an automobile - Google Patents

Abstract

443,617. Operating clutches. BENDIX AVIATION CORPORATION, 105, West Adams Street, Chicago, U.S.A. Jan. 7, 1935, No. 497. Convention date, Jan. 8, 1934. [Class 80 (ii)] [See also Groups XXXIV and XXXI] A fluid-pressure cylinder 56 is actuated to disengage the clutch of a motor-vehicle and to apply the brakes under the control of a fluidpressure operated valve responsive to actuation of the accelerator or brake pedal. A source of vacuum is connected to the cylinder 56 to disengage the clutch through a governor valve 52, by a valve 36 when the accelerator pedal 20 is released. The governor valve 52 ensures only sufficient vacuum in the cylinder to disengage the clutch and the clutch spring is weaker than the brake spring. When the brake pedal 92 is depressed a valve 48 is operated to cause further operation of the governor valve 52 to produce a higher vacuum in the cylinder sufficient to operate the brakes. The clutch operating lever 90 is connected to the piston rod 82 and in the clutch disengaged position engages a stop 108 which acts as an abutment to allow the operation of the brake lever 76 by the movement of the cylinder 56. The governor valve 52 comprises a diaphragm 142, Fig. 3, fixed to a valve head 138 and a sleeve valve 164 fitting in an annular groove 166 in the valve casing. The valve head 138 is normally raised from the sleeve valve 164. The space above the diaphragm is normally connected to atmosphere by a pipe 62 and the brake valve 48. When a source of vacuum is connected to the port 112 by the valve 36 on the release of the accelerator pedal 20, it acts through the space between the valves 138, 164 and pipe 54 and in the cylinder 56 to disengage the clutch. The vacuum thus produced below the diaphragm 142 closes the valve 138 on the valve 164 and closes the connection between the vacuum and the cylinder 56. When the brake pedal 92 is depressed the valve 48 is operated to connect the space above the diaphragm 142 to vacuum by pipes 62, 44 whereupon the valve 138 rises and produces an increased vacuum in the cylinder 56 to operate the brakes. The degree of vacuum is graduated according to the position of the pedal 92, the movement of the brake lever reclosing the valve 48 if the pedal is held stationary and the valve 138 is thereupon closed by the equalization of the vacuum on both sides of the diaphragm 142. Cushioning of the clutch-engaging movement of the piston of the cylinder 56 is obtained by controlling release of air from the reverse side of the piston by a needle valve 190 operated by the accelerator pedal and also by a groove in the piston rod which is uncovered in certain positions.