Patent GB-1028716-A (GB)
Title: Improvements in or relating to clutch actuation mechanisms
IPC: F16H45/00
Filed: 1964-01-14
Abstract: 1,028,716. Change speed and clutch control. SOC. ANON. FRANCAIS DU FERODO. Jan. 14, 1964 [May 10, 1963], No. 1671/64. Headings F2C, F2D and F2L. In an hydro-pneumatic clutch control for a motor vehicle main clutch E which is in series between an hydrodynamic torque converter C and a change speed gear B, wherein a valve 31 controlling the flow of pressure liquid to the clutch E is positioned by a pneumatic servomotor 40, the working chamber 41 of which is selectively connected by a relay valve 45 to atmosphere at 60 or to a vacuum reservoir 56, the valve 45 is operated by the pressure in a chamber 62 which is permanently connected to the vacuum reservoir 56 through an orifice 64 and is vented through one or more control valves 65. The control valve 65 may be operated by movement of the gear shift levers, when the gear is in neutral, when the bonnet is raised as when the driver's seat is unoccupied. Clutch and torque converter.-A driven plate 18 of the clutch E is normally clamped between driving plates 17 fast with a turbine T of the converter by the pressure liquid in the converter casing. Pressure liquid is continuously supplied through a line 33 to the converter C and is returned to sump through a restricted orifice 27, one-way valve, clutch chamber 28 and line 30. For disengagement of the clutch E the valve spool 32 is moved to its lower position in which it supplies pressure liquid to the clutch chamber 28 to separate the plates 17 and connects the torque converter C to exhaust. Fluid system.-A pump 35 supplies pressure liquid to the valve 31 and the pump output pressure is limited by a pressure relief valve 37. The valve spool 32 is urged towards the position shown by a spring 42 for clutch engagement and is moved down for clutch disengagement by connecting the chamber 41 to the vacuum reservoir 56. The reservoir 56 is connected through a one-way valve 57 to the engine inlet manifold and through the orifice 64 to the chamber 62 so that when the valve 65 is closed the depression in the chamber 62 moves the relay valve spool 47 down against the action of a spring 63 to the position shown, wherein it connects the chamber 41 to atmosphere at 60. Opening the valve 65 admits air to the chamber 62 to permit the valve spool 47 to move up and connect the chamber 41 to the reservoir 56. In Fig. 3, two control valves 65a, 65b are provided, the former of which is opened during gear shift movement whilst the latter is opened when the gear is in neutral. The valve 65a is provided between the upper rod 72 and lower part 73 of the gear shift lever. A spring 80 normally maintains the rod 72 central relative to an aperture 81 in a cover 76 fast with the lower part 73 of the shift lever so that a seal 78 closes an air inlet 66a. Initial movement of the gear shift lever tilts the rod 72 relative to the lower part 73 to open the valve 65a and admit air to the chamber 62. The valve 65b is provided between the valve 65a and chamber G2 and comprises a spring-loaded valve plate 85 which is moved up to open the valve by a plunger 90 engaging a portion 92 of a shift rod 26 when the latter is in a neutral position. In Fig. 5 (not shown), a neutral detecting plunger acts through a spring on the spool 47 of the valve 45. In Figs. 6-8 (not shown), the valves 45, 31 are formed in a single housing.