Patent GB-521748-A (GB)
Title: Improvements in or relating to control mechanism for the drive of a motor vehicle
IPC: F16H63/30
Filed: 1938-10-25
Abstract: 521,748. Controlling variable-speed gearing. CHRYSLER CORPORATION: Oct. 25, 1938, No. 30812. Convention date, Nov. 18, 1937. [Class 80 (ii)] The invention is shown applied to planetary gearing B having three forward driving-speed ratios and a reverse drive selectivity brought into operation by brake bands 33, 34, 36 and a friction cone clutch 35 which respectively control the drives for first or low speed, second speed, reverse, and high speed, and are actuated by pressure fluid under the control of a handoperated distributing valve H, Figs. 1, 3, 7. Associated with each device 33 ... 36 is a piston &c. located in a cylinder D ... G having pressure fluid, e.g. oil, pipes 77 ... 80 leading from the casing 62 of the valve H, the latter being provided with high and low pressure chambers 66, 67 respectively formed, as shown in Fig. 3, by projections 64, 65 on the valve proper 63. A pressure oil supply pipe 68 communicates with the chamber 66 and the pipes 77 ... 80 with the chamber 67, a passage 76 in the valve 63 permitting communication to be established between the chamber 66 and any one of the said pipes by corresponding rotation of the valve; the passage 76 may also be aligned in a neutral position with that part 81 of the valve casing 62 between the pipes 77, 80. The valve is rotated by a selector lever 90 on the steering post 87 which is connected by a Bowden wire 98 to a lever 85 thereon. Interposed in the pipes 78, 79 leading to the high and second speed chambers E, F is a secondary control J which is actuated by movement of the accelerator pedal 100 beyond its position of maximum throttle opening and, with pressure oil being supplied to the cylinder E through passages 143, 144 in the casing 132 of said control, breaks the connection between the passages 143, 144 and effects communication between the passage 143 and a passage 142 leading to the cylinder F to change the gear ratio from high to second, independently of the valve H. The control J comprises spring-pressed leader and follower slide valves 150, 151 with an interposed abutment plug 160, the valve 150 being connected by a lever 137 and Bowden wire 131 to a lever 128, Fig. 1, adapted to be actuated by a finger 127 on a link 126 interposed between the accelerator pedal 100 and the throttle 107. Fig. 7 shows the control J with pressure oil flowing from the passage 143, ports 171, 172 and passage 144 to the high-speed cylinder E, but, upon actuation of the Bowden wire 131, the valve 150 is moved to the left and pressure oil from a passage 190, leading from the passage 143, flows through ports 188, 189, 192, Figs. 7, 8, and effects movement of the valve 151 to the right, whereupon communication is established between the passages 143, 142 through ports 171, 168 and the pressure oil flow is transferred to the secondspeed cylinder F, the valves returning to their normal positions upon release of the accelerator pedal. The Specification as open to inspection under Sect. 91 describes also a modification in which the leader valve 150, instead of being connected to and actuated by the accelerator pedal, is actuated by the variation in the vacuum in the intake manifold of the engine consequent upon a variation in the throttle opening. This subjectmatter does not appear in the Specification as accepted.