395,504. Controlling motor vehicles. RENAULT, L., 8, Avenue Emile Zola, Billancourt, Seine, France. June 20, 1932, No. 17413. Convention date, Aug. 27, 1931. [Class 79 (v).] Comprises automatic clutch control in which the engagement and disengagement of the clutch is controlled by the accelerator pedal, the brake pedal, and a synchronizing device which prevents clutch engagement as long as the two clutch parts have substantially different speeds, means being provided whereby the clutch is engaged whenever the brake pedal is operated in spite of the synchronized action, either by allowing a gradual engagement of the clutch, or by causing the throttle to be momentarily opened, or by both methods. In the construction shown the clutch pedal 1 is connected to a piston 4 working in a cylinder 3 connected by a pipe 13 and valve 7 to the engine induction pipe 5. The valve 7 has an arm 8 forced by a spring 9 against an arm 10 on the accelerator pedal 11 so that in the position shown, in which the accelerator pedal is released, the valve 7 is open and the clutch is disengaged. The accelerator pedal, when it is depressed, before it acts on the throttle 21 by means of a rod 34, moves away from the arm 8 and allows the spring 9 to rotate the valve 7 to connect the pipe 13 to the atmosphere at 12 instead of to the induction pipe. A non- return valve 6 in the pipe 13 prevents the cylinder 3 from being connected directly to the atmosphere, so that normally the clutch is not engaged until a valve 15 in a byepass 14 is opened by a synchronizer 27. The brake pedal 16 is connected by a link 17 to an eccentric 19 which, when the brake pedal is depressed, depresses the accelerator pedal 11 and rotates the valve 7 to cause the clutch to engage so that the engine can be used as a brake. If the synchronizer keeps the valve 15 shut and thus prevents the clutch from being engaged air can pass gradually from the atmosphere into the cylinder 3 through a small leak 20 and the clutch will be engaged gradually. As an alternative or additional method the brake pedal 16 is connected to a valve 25 which is opened when the pedal is depressed and connects the cylinder 3 with a cylinder 23 containing a piston 22 connected to the throttle 21. As the clutch is still disengaged there is a partial vacuum in the cylinder 3 and this causes sufficient vacuum in the cylinder 23 to operate the piston 22 and open the throttle, thereby speeding up the engine until the synchronizer operates the valve 15 and allows the clutch to engage. As soon as the clutch is engaged atmospheric pressure is restored in the cylinder 23 and the throttle is closed by its spring. The automatic de-clutching action may be dispensed with by rotating the eccentric 19 by a handle 18 so as to act through the pedal 11 on the valve 7 ; the clutch is then controlled solely by its pedal 1. The clutch synchronizer comprises a differential gear the sun pinion 27 being driven by one clutch member and the planet carrier 26 by the other, the toothed annulus 28 having its periphery in contact with an eccentric 29 pivoted at 30 on a spring- controlled lever and connected by a link 39 to the valve 15. It is stated that rotation of the annulus 28 in the counterclockwise direction causes frictional drag on the eccentric 29 and moves the link 39 so as to rotate the valve 15 and connect the pipe 14 to the cylinder 3. If, however, the annulus rotates in the clockwise direction it slips under the eccentric 29. The differential gear is so arranged that the annulus 28 is stationary when the two clutch parts rotate at the same speed. If the engine speed is then increased slightly the annulus 28 begins to rotate counterclockwise and the valve 15 is opened and the clutch engaged. The outer part 29 of the eccentric may be rotatable with some friction on the inner part 40. In a modification, Fig. 8 (not shown) instead of using the eccentric 29 the annulus 28 is connected to a shaft surrounded by a spring coil having an arm at one end connected to the valve 15 and an arm at the other end floating between stops, the effect being that of a oneway clutch so that the coil only grips the shaft and acts on the valve when the shaft is rotating in the counterclockwise direction. In the modification, shown in Fig. 3, the connections between the three pedals are entirely mechanical, the clutch and brake pedals 1, 16 being connected to a floating lever 46 having a free end 47 adapted to act on the rod 34 operating the throttle. When the clutch is held disengaged by the servo cylinder the pedal 1 is depressed and rocks the lever 46 about its centre. If now the brake pedal 16 is depressed it rocks the lever 46 about the clutch pedal end and the end 47 acts on the rod 34 and opens the throttle. The engine speed is thus increased until the synchroniser allows the clutch to engage and the pedal 1 to return to its raised position ; this rocks the lever 46 and withdraws the end 47 from the rod 34 so that the throttle closes again. Specification 392,267 is referred to.