Abstract: A grinding tool with a cylindrical sleeve, having several longitudinally extending slots penetrated by radially shiftable wedge-shaped bars with abrasive outer faces, is provided with a mandrel received in the sleeve and axially displaceable therein for shifting the bars radially outward and inward. The mandrel has longitudinal guide grooves with sloping bottoms, engaged by the correspondingly sloping inner faces of respective bars, and a shallower annular groove of frustoconical bottom intersecting these guide grooves; segments of a frustoconical ring, lodged in the annular groove and projecting into the intersecting guide grooves, engage in mortises of adjacent flanks of respective bars sliding in the guide grooves for positively shifting the bars when the mandrel is displaced in one of the other axial direction.

Abstract: A device for automatically and selectively breaking an electric circuit, comprising an actuating member such as a steering column with which is associated a freely rotatable cam and two stops limiting the cam rotation to an angle below 90.degree. so that the cam may act on movable contact pieces positively or not in accordance with the motion of the actuating member in one direction or the other direction, the device being applicable to the operation of the blinkers of an automotive vehicle.

Abstract: A retainer for the parts of the interior assembly of sliding automotive universal joints, for example, of the tripod type constituted, of a splined hub with trunnions which support rollers with interposed bearing means, such as needle bearings. The retainer (1) is a flat slitted ring (2) made of a slightly elastically deformable material and has regularly spaced open seats (L) for receiving rollers (12), and holder (6,7) to retain the rollers (12) and needle bearings (13) in position on the trunnions (11) of the interior assembly of the universal joint.

Abstract: A universal coupling comprising an outer element integral with a first shaft having a spherical cavity inside which are formed grooves, an inner element integral with a second shaft and having an external surface in which grooves are also formed whose bottom has a section through a plane passing through the axis of the inner element formed by an arc of a curve, rolling means being disposed between the pairs of grooves, these rolling means being held in the windows of a cage. The inner element has on its outer surface a cylindrical surface portion situated substantially in the median region in the axial direction and extending at least substantially as far as the plane orthogonal to the axis containing the points of the bottoms the furthest from the axis, this portion being extended on each side by spherical surface portions intended to mate with the inner surface of the cage.

Abstract: A universal joint is provided comprising an outer substantially bowl-shaped element having a cylindrical bore in which are formed tracks, an inner element housed in this bore and having a convex external surface provided with grooves, and connecting balls, disposed respectively in a track of the outer element and in a groove of the inner element. These connecting balls are held in position by a cage which has a concave internal surface adapted to cooperate with the convex external surface of the inner element, and a convex external surface. The clip is also provided with positioners removable positioning means for securing the cage with respect to the outer element.The removable positioners are formed by an expandable holding clip comprising at least two diametrically opposite lugs adapted to surround the cage and having a concave shape so as to cooperate with the external surface of this cage. These lugs are engaged in grooves formed in the internal wall of the outer elements.

Abstract: A tool for lapping internal surfaces of holes.Lapping tools conventionally have an expandable working portion for variable diameter operation. Known tools tend to expand in a barrel shape leading to inaccurate lapping. The invention seeks to avoid this by providing a working portion of a tubular tool with slots in a plurality of rows each having several slots. Slots in each row are staggered relative to those in adjacent rows.

Abstract: A device for supporting a steering and driving wheel of an automobile vehicle comprises a hollow hub constituting the outer element of a ball joint of which the inner element is fixed on a drive shaft, a seal element made of sheet metal being provided at the open end of the hub, opposite the joint. A brake disc having a central opening is fixed on the hub on the same side as the wheel. The seal element is in the form of a bowl whose closed end is fitted in the hollow hub and whose length is such that the other end, of outer diameter substantially equal to the diameter of the opening in the brake disc, opens outside the hollow hub and passes through the disc, centering same.

Abstract: An assistance mechanism is provided, which is adapted to be coupled to a driven member capable of rotating alternately in both directions, in response to the rotation of a drive shaft. The assistance mechanism comprises a motor, a device for reducing the speed of the motor and at least one clutch actuated by a controller. The controller includes a part which is coaxial with the driven member and slides against a resilient return spring in relation to the amplitude and the direction of the torque applied by the drive shaft. Each clutch is mounted on a shaft of the device for reducing speed, which rotates faster than the driven member. The controller further comprises a connection between the sliding part and the clutches.This rotary assistance mechanism is particularly suitable for use in conjunction with vehicle steering mechanisms.

Abstract: A spark ignition system for a gas turbine electronically controls the cycle of charge and discharge of a spark generator of the capacitive type. There is a function generator (5) which derives a reference voltage as a function of the speed of the turbine and possibly of other parameters. A charge control (6) for the capacitive cell (9) and a spark frequency control (7) are controlled by the reference voltage. Reignition in the case of flame extinction is controlled by an opto-electronic arrangement (11, 12, 13) which drives a reignition circuit (14), when flame extinction is detected. The reignition circuit produces a voltage which is superimposed on and over-rides the speed reference voltage to activate the system to produce ignition at a start condition.The system can be used for ignition of a gas turbine, especially a turbo-compressor.

Abstract: A two-speed drive coupling for connecting an engine of a motor vehicle with an accessory such as an alternator. The coupling comprises a driving member and a driven member with a sun gear being mounted on the driven member. A planet gear wheel holder is carried on the driving member and carries planet gear wheels which mesh with the sun gear and with a crown gear locked against rotation and surrounding the sun gear. A unidirectional coupling is provided between the driving member and the driven member and a centrifugal clutch between the driving member and the holder. At low speeds of the driving member, the clutch is engaged and the driven member is rotated at a greater speed than the driving member through the planet gear wheels and the sun gear. At higher speeds of the driving member, the clutch disengages and the driven member is rotated directly by the driving member through the unidirectional coupling.

Abstract: This rotating joint (7) has an axis (Y--Y) parallel to the axis of the pivotable mounting of the engine. The joint comprises two annular planar surfaces (18, 19) having the same axis (Y--Y) and respectively rigid with the two elements of the exhaust pipe (6, 9) to be interconnected. These surfaces are separated by a heat-resistant anti-friction ring (20) and are biased toward each other by a pivotal U-shaped element (21). Application in vehicles having a transverse front engine.

Abstract: A rotary assistance device (D) is provided adapted to be coupled to a driven member (1) capable of rotating in both directions, particularly in response to the rotation of a drive shaft (4), this device comprising a motor (M) able to rotate at a relatively high speed with respect to that of the drive shaft (4) and of the driven member (1), speed reducing means (7) and friction coupling means (E1, E2) for driving the driven shaft (1) through the speed reducing means (7) and the motor (M). The device comprises angular torque damping means (A) disposed between the motor (M) and the friction coupling (E1, E2).

Abstract: A convertible seat structure for an automobile vehicle includes a seat pivotably connected to the vehicle by a link member and a backrest pivotably connected to the vehicle at a pivot. At least one connecting bar connects the backrest and the seat with a pivotal movement of the backrest moving the seat longitudinally with respect to the vehicle and pivotally about the pivotal connection with the link member.

Abstract: The exhaust silencer of the invention improves the various attenuation characteristics without increasing the overall size of the silencer. This is achieved by disposing the pressure take-off of the low-frequency resonator in an end wall of the case of the silencer and by placing the neck of this resonator partly outside the case. The associated chamber is located inside the reflection and interference attenuation stage.

Abstract: A sliding universal joint for automobiles having a driving element in the form of socket, connected to a driving shaft and having at least two roller tracks cooperating with rollers mounted by their bores on trunnion pins of a hub connected to a driven shaft. Retainers (11, 21) for retaining the rollers (5) on their trunnion pins (6) are provided with toothed friction surfaces (16, 24) to hold the rollers during manipulation, and against the centrifugal force which occurs during functioning of the joint.

Abstract: Power steering with rotary drive shaft adapted to drive a pinion cooperating with a rack, comprising a distributor of pressurized fluid which comprises a slide valve coaxial with the pinion and a connecting rod passing axially through the pinion and connecting one end of the slide valve to a piece linked in rotation with said shaft, but free to slide with respect to this shaft, said piece being adapted to cooperate during its rotation with a bearing surface immovable in the direction of the axis of the pinion and sloping with respect to this axis, so that said piece, the rod and the slide valve move axially in response to a rotational movement of the shaft.

Abstract: The back of a retractable shelf is pivotally connected to a rear door or trunk lid, for example, of a hatch-back automobile. A flexible element is connected to the front of the shelf, extends through a bearing on the rear door, and is anchored to the vehicle to support the shelf in a horizontal position when the rear door is closed. The anchor point, and bearing location on the rear door are such that the bearing moves away from the anchor point as the door is opened, thus pulling the flexible element through the bearing to retract the shelf against the door, when the door is fully open.

Abstract: A disc brake comprises an operating piston mounted in a cylinder rigid with a stirrup. The piston is movable in the cylinder to cause axial movement of friction linings under the action of hydraulic pressure or the force of a mechanical brake actuator. An operating clearance is provided to allow a limited retraction of the friction linings when the hydraulic pressure or the mechanical actuating force is released. The mechanical actuator comprises a screw rotatable in the cylinder. A nut engaged by the screw is connected to the piston by a unidirectional coupling device comprising teeth on the nut co-operating with teeth on a ring fixed for rotation with the piston. The nut is mounted for translatory movement in relation to the piston solely through a limited distance corresponding to the operating clearance, and the ring is mounted for axial displacement relative to the piston.

Abstract: The invention relates to a device for detecting combustion defects in an internal combustion engine which are in the form of pinking. The device comprises a detector placed on the cylinder head of the engine and a system for utilizing the signals of the detector. The system comprises means for converting the analog data delivered by the detector into digital data, means for temporarily storing, in the course of each cycle, the digital data relating to each cylinder of the engine, and means for comparing the data relating to each cylinder, stored in succession in the course of a cycle, with corresponding data obtained in the course of the following cycle.The device is applicable in particular in devices for initiating the ignition of an engine.

Abstract: The mechanism comprises a clutch and a gear box having a plurality of speed ratios disposed between a motor and receiving means. Means are provided for acting on the speed of the motor so as to bring the input element and the output element of the clutch to substantially the same speed before the engagement of the clutch. The mechanism further comprises in combination a detector of the speed of the motor, a detector of the speed of the receiving means, a numeric calculator of the theoretical speed of one of these components as a function of the speed of the other component and of the engaged speed ratio of the gear box, and a comparator of the calculated speed and the measured speed which has its output connected to the means for acting on the speed of the motor.