Patent GB-403185-A (GB)
Title: Improvements in or relating to devices for controlling the clutches of motor vehicles
IPC: A43B13/38
Filed: 1932-09-01
Abstract: 403,185. Operating clutches. KNORRBREMSE AKT.-GES., 9, Neue Bahnhofstrasse, Lichtenberg, Berlin.-(Assignees of Ges. fur Autotechnik ; 8, Chausseestrasse, Berlin.) Sept. 1, 1932, No. 24418. Convention date, Nov. 26, 1931. [Class 80 (ii).] A clutch-control for a motor vehicle comprises a servomotor operated by engine suction, the engagement of the clutch being damped to an extent depending on the degree of depression of the accelerator pedal, which varies the crosssection of the opening allowing flow of air or other damping - medium to or from the servo-cylinder or the like. In the form shown in the Fig., the clutch pedal 4 is operated by a servo-cylinder 1 which may be connected to the engine induction-pipe 7 or to atmosphere by a valve 8 operated by a solenoid 9 under the control (1) of a contact 12 on the accelerator pedal 13 in series with a contact 15 which is broken by the attraction of the solenoid 20 on the armature 16 when the current of the charging-dynamo 22 increases owing to an increase in the engine speed, and (2) of a contact 18 on the gear-lever 19 in parallel with the contact 12. When the engine is idling, the parts are in the position shown, the clutch being disengaged. On depressing the accelerator pedal 13 slightly, the contact 12 is broken and the valve 8 operates to communicate the motor 1 to atmosphere, allowing the piston 2 to move to the right. After the piston has passed the non-return valve 24, the remaining air bleeds slowly through the valve 35, thus allowing the clutch to engage slowly. If, however, the accelerator pedal is further depressed, the tapered valve 28 is opened by its spring 29, allowing the air to escape from the cylinder 1 at an increased rate depending on the degree of depression of the pedal. Some lost-motion is provided by the springy contact 32 between the throttle-operating rod 30 and the valve 29, so that the throttle opens before the clutch engages. In a modification a slack cord is used. If the accelerator pedal is released while the vehicle is travelling fairly slowly, the clutch is re-disengaged owing to the remaking of the contact 12, but, if the vehicle is moving at more than a certain speed, the clutch is not immediately disengaged, since the circuit of the electromagnetic valve 8 is broken at 15 owing to the high current generated in the solenoid 20 by the charging-dynamo 22. Specifications 353,636, 371,923, and 372,553, [all in Group XXXI], are referred to. The Specification as open to inspection under Sect. 91 comprises the following subject-matter. The clutch lever 4, Fig. 3 (Cancelled), is operated by a piston 2 in a cylinder 1 controlled by a pedal 44, which, when depressed, connects the cylinder 1 to the engine induction 7 through pipes 43, 6 and the waist of the valve 41, 42. On releasing the pedal 44, the valve 41, 42 moves to the position shown, and the clutch moves rapidly towards the engaging position, air entering the cylinder 1 through the holes 38, 39 in the valve mechanism until the hole 38 is obstructed by the-piston 37 which moves with the piston 2. The rate of final engagement is determined by a further influx of air through the tapered valve 28, which is operated by the accelerator pedal 13 as described in connection with Fig. 1. This subject-matter does not appear in the Specification as accepted.