Patent GB-963261-A (GB)
Title: Improvements in and relating to clutches
IPC: F16D27/02
Filed: 1960-10-10
Abstract: 963,261. Controlling clutches. FRANCAISE DU FERODO S.A. Oct. 10, 1960 [Oct. 12, 1959], No. 34714/60. Heading F2L. The electrically-engaged clutch of a motor car is fed with current through a circuit including a rheostat adjusted by depression of the normal accelerator pedal to give decreasing resistance, the connection between the accelerator pedal and the rheostat comprising a system of links one of which is of variable length and is controlled by a factor such as the depression in the inlet manifold of the car engine or of the engine speed. In the form shown, the usual accelerator pedal 55 is connected through links 54, 57 to a butterfly valve 58 between the carburetter and the inlet manifold of a car engine, a shaft 50 carrying links 52, 53 in the pedal linkage and turning therewith being fast with a fork 49 connected through links 44, 42 to a sliding contact 23 adjustably positioned relatively to the studs 21 1 -25 4  of a rheostat in the control circuit of the car main clutch 10. Depression of the accelerator pedal 55 moves the rheostat contact 23 towards the end stud 25 4  of the rheostat, to reduce the resistance in the clutchenergizing circuit. Between the fork 49 and the link 44 of the sliding contact operating linkwork, is connected a vacuum operated flexible diaphragm servomotor 46. The suction side 47 of the servomotor is connected through a pipe 60 to the inlet manifold 59 of the car engine, the vacuum working against the bias of a spring 48 to move the sliding contact 23 towards the stud 25 1 , thus introducing increased resistance into the clutch control circuit. The pipe 60 is of substantial volume, and has a trottling restriction 61 adjacent the end connected to the engine inlet manifold, so that fluctuations in inlet manifold depression are not instantly effective upon the servomotor. The sliding contact 23 is connected to the clutch 10 through a circuit including a rheostat 22 adjusted to compensate for wear of the clutch friction linings, and a switch 16 opened by a solenoid 18 under the control of a gear-shift lever 41 actuating a switch 40. Current is supplied to the rheostat 26 either from an engine-driven generator 34, by moving a switch 28 to close a circuit through a line 27, or alternatively by moving the switch 28 to close a contact 32 and make a circuit from a battery 36 connected through the usual ignition switch 37 to the positive terminal 39 of the ignition coil 38. The sliding contact 23 and the link actuating it are so dimensioned that when the accelerator pedal 55 is released and the engine is stopped, the contact 23 is on the stud 25 2 , whereby the clutch 10 is maintained engaged for parking, but when the engine is iding with the accelerator pedal released, the sliding contact moves on to the stud 25 1 , for virtually complete clutch disengagement. When the accelerator pedal is fully depressed and inlet manifold depression is very small, the contact slider 23 moves on to the contact stud 25 4 , all resistance of the rheostat being shorted out from the clutch control circuit. Reference has been directed by the Comptroller to Specification 732,513.