Patent GB-457108-A (GB)
Title: Improvements in gear shifting mechanism
IPC: F16H61/02
Filed: 1935-05-20
Abstract: 457,108. Controlling change speed gearing and clutches. BENDIX AVIATION CORPORATION, 105, West Adams Street, Chicago, U.S.A. May 20, 1935, No. 14714. Convention date, May 21, 1934. [Class 80 (ii)] A selector-valve 52, Fig. 3, which controls a gear-establishing fluid-pressure motor 16, Fig. 2, is operated at will, either manually by rocking a treadle 62, or through power-means 154 under the control of a manual preselector-lever 192, a common linkage 64 serving to connect both the treadle and power-means to the selector-valve. The gear-establishing motor 16 and a motor 32, Fig. 1, for disengaging the main-clutch 48 during a change, are energized by engine-suction, under control of a common valve 36, operated by the vehicle accelerator-pedal 34, the fluid ports being so proportioned that the clutch-motor is energized first. There is also a spring-loaded one-way check-valve in the suction-inlet 136 of the selector-valve 52, which ensures the maintenance of sufficient suction in the motor 16 to complete a shift even if the accelerator-pedal is prematurely released. Power preselection is electrically performed. The arrangement is similar to that described in Specification 443,718, a conventional threespeeds and reverse shifter-lever 14 being connected directly to the piston-rod 22 of the double-acting gear-establishing motor 16, which is universally mounted at its head 18, so as to swing bodily in a transverse plane for effecting the cross-shift movements of the lever 14. A spring 96, Fig. 3, constantly biases the motor and lever assembly into the plane for selecting second-and high-speeds, and opposite movement to the low-and-reverse plane, Fig. 3, is effected by a suction-energized cross-shift motor 100, the diaphragm 86 of which is pivoted to a reaction lever 90, pivoted at 92 to the motor-assembly 16 and providing a fulcrum at its free end. The cross-shift motor 100 is controlled by a three-way solenoid-valve 68, Fig. 5. The power-means 154, Figs. 2 and 13, above referred to, for operating the selector valve 52, comprises a double-acting suctionmotor, controlled by two three-way solenoidvalves 162. The solenoid-valves 68, 162 are controlled by a preselector switch 74 on the steering-column. This switch is operated by a miniature lever 192, Fig. 14, the movements of which simulate, to a certain extent, those of the conventional gate-guided shifter-lever 14, for, when the lever 192 is slidden laterally in its housing 74, to the left of Fig. 14, it makes a contact 216 which energizes the solenoid-valve 68 of the cross-shift motor 100, thereby swinging the motor and lever assembly laterally into the low-and-reverse channel. Fore-and-aft movement of the lever turns a cam 208 which closes contacts on either side, leading respectively to the solenoid-valves 162, Fig. 13, of the selector-valve operating-motor 154. A spring 194 returns the lever laterally to the right of Fig. 14, thereby de-energizing the cross-shift motor 100 and leaving the spring 96 free to bias the shifter-lever 14 into the second-and-high channel. As is also described in Specification 443,718 there is a speedometer-controlled switch, which, when the vehicle is at rest, makes a contact energizing a relay which completes a circuit to the solenoid-valve 68, thereby energizing the cross-shift motor and biassing the shifter-lever into the low-and-reverse channel. In order to permit engagement of second speed direct from standstill, by use of the foot-treadle 62, the downward movement of the selectorvalve 52, Fig. 5, breaks a contact 80, which de-energizes the solenoid-valve 68 and so allows the shifter-lever 14 to be spring-biassed into the second-and-high channel. The contact 216 of the preselector-switch 74 is arranged in a shunt circuit with the speedometer-switch and the switch 80, so that, to obtain reverse, the contact 216 must always be closed first. The clutch-motor 32 comprises an inertia-controlled valve for regulating clutch-engagement, as described in Specification 412,184, and may have a lost-motion connection with the foot pedal. The Specification as open to inspection under Sect. 91 described also a modification in which a non-manual selector-valve is operated electrically only. This construction forms the subject-matter of Specification 457,179 and does not appear in the Specification as accepted.