Abstract: A speed change device comprises a stack of discs alternating with friction rings, the rings being disposed in a drum with which they are rotatable, the discs being rotatable with an input shaft extending into the drum. The stack is gripped between an abutment connected to the drum and a bell-shaped member fixed to an output shaft extending into the drum. The gripping is ensured by clamping means comprising elements having complementary conjugate surfaces and resilient means disposed between one of said elements and an axial abutment movable with the drum or bell-shaped member. The elements of the clamping means comprise a screw rotatable with the output shaft but axially movable therealong and a nut co-operating with the screw, the nut being rotatable with the drum but axially movable therealong.

Abstract: In an automobile, a device for monitoring the flow and temperature of the coolant in the internal combustion engine, comprising a switch of a supply circuit for an alarm, whose mobile part is controlled by a single detector detecting both flow and temperature, disposed at one point of the cooling circuit.

Abstract: An elastic coupling for two elements having non-uniform characteristics of rigidity, the coupling being constituted by two interfitting parts held fast by an elastic sleeve having zones weakened by free spaces made between one part and the sleeve at the ends of the coupling in zones which are symmetrical with respect to a theoretical axis of relative pivoting of the two parts. The invention finds advantageous application in the domain of automobiles.

Abstract: A device for regulating the transmission of a vehicle incorporating a speed variator and a reverse gear has a hydraulic regulating member and an electrically operated valve disposed in a discharge conduit of the member. Two parallel normally open arms of the energizing circuit of the valve may be closed by two switches respectively operated by a member connected to the accelerator of the vehicle and by a member connected to the reversing gear, energization of the electrically operated valve leading to an interruption of the discharge conduit of the device.

Abstract: A device for regulating the operation of the transmission of a motor vehicle having a variator including a distributor which is influenced by a centrifugal regulator and/or resilient means which may be additionally controlled by an accelerator, for supplying pressure fluid from a source to a cylinder chamber or for connecting the chamber to a reservoir, a piston movable in said cylinder chamber being connected to a step-down control element of the variator. As a safety device to prevent imbalance in the event of a failure of the centrifugal regulator, a two-piston electrically operated valve is incorporated between said source and said chamber, the valve being controlled by an electrical circuit arranged to close the valve and prevent the flow of pressure fluid from the source to the chamber if the speed of the engine exceeds a predetermined value. If desired, the valve may serve to control flow of pressure fluid to and from a hydraulic brake for the input shaft of the variator.