Abstract: The apparatus comprises a support for supporting a blank in which at least one groove having a curved axis and a circular section is to be formed, a ball for forming the groove and carried at one end of a ball holder, a device for displacing the ball holder, and an articulated quadrilateral structure which has a first side rigid with the support and a second side in which the ball holder is fixed by an end of the ball holder. The second side is opposed to the first side of the quadrilateral structure. Thus the ball holder is movable relative to the support by the ball holder displacing device. An application of the apparatus is in the forming of runways in transmission joints of the tripod type.

Abstract: This bearing is intended to be employed under a radial load of roughly constant direction, while it is capable of resisting axial forces and tilting moments. It comprises two rows of balls which circulate in raceways formed in a rotating center ring and fixed lateral rings. According to the invention, the distance between the bottom of grooves, formed in the lateral rings and constituting the raceways, and a reference plane, is variable and reaches a maximum value at two diametrically opposed points which are located in a diametrical plane perpendicular to the direction of the load.

Abstract: On the periphery of the ball bearing, six regions alternately ensure upon assembly of the bearing a pre-stressing of the balls in each direction, and six unloaded regions separate these bearing regions. In this way, the bearing is rendered rigid as concerns a tilting moment and there is a low rate of sliding of the balls and it is possible to assemble the bearing by disposing the two rings and the cage coaxially and then inserting the balls one by one through a radial aperture formed in one of the rings and opening onto an unloaded region. Application in the mounting of automobile vehicle wheels.

Abstract: The joint comprises two opposed forks which are angularly offset from each other at 60.degree. and are axially extended by nose portions which are internally spherical. These nose portions swivel on a ring through which extends with a large clearance a shaft section which carries at each end a tripod element associated with one of the forks. The ring is maintained roughly in the bisecting plane of the joint by contact or quasi-contact with the rollers of the two tripod elements. In this way it is possible to produce steering road wheel homokinetic joints which are capable of operating at angles of 50.degree. and more with no reduction in their transmitting capacity.

Abstract: This transmission shaft comprises a first transmission element having high torsional elasticity which is rigidly connected to rotate at its ends with the output shaft of the engine unit of the vehicle and a front wheel, and a second transmission element having a low torsional elasticity coaxial with the first transmission element. The second transmission element has one end rigidly connected to rotate with the wheel and another end connected to the shaft through a connection which has an angular play between two predetermined values of the torque applied to the shaft. The drag torque applied to the shaft when the engine is idling and the vehicle is held stationary by the brakes, is between these two values.

Abstract: In one embodiment the spring comprises a coil which extends through a coiling angle which is slightly less than 360.degree.. The end portions of the coil are curved in a direction for decreasing the pitch of the helix in the working position of the spring between two surfaces. This spring assumes such position that it comes in contact at two points with each of these surfaces and the forces are distributed in an excellent manner.Application in particular to the mounting of rollers on trunnions of homokinetic tripod joints.

Abstract: The method permits mass-producing axially retained tripod joints having high rigidity and a given prestressing force which is reproducible from one joint to another. According to this method, after having clipped a resiliently yieldable attachment onto a tulip-shaped element of the joint while the joint is in its assembled position, the value of the gap between the shoulder of a thrust member and a bearing surface of a hub carrying the trunnions is determined for the position of the joint in which the hub and tulip-shaped member are in alignment and the thrust member is axially shifted away from the hub and there is introduced in the gap produced between the thrust member and the hub a shim the thickness of which is chosen to be slightly larger than the gap.

Abstract: In the joint, the raceways of the tulip element have the shape of a torus. The ratio of the maximum distance between the axis of the tulip element and the axis of the tori defining the raceways to the radius of said tori is between 1/4 and 3/4. This results in a considerably improved mechanical efficiency and consequently in a reduced opposition to sliding.Application of the joint to automobile vehicle transmissions.

Abstract: The transmission comprises two slidable tripod joints. In each joint, the tulip element is extended around the shaft of the tripod element by an abutment member which defines a concave part-spherical surface. A check member having a convex part-spherical surface fitting the concave surface is disposed around the shaft between the tripod element and the abutment member with a radial clearance which is at least equal to the amplitude of the orbital movement of the tripod element at the maximum angle of deviation of the joint. Each joint has a spring which is compressed between the inner end of its tulip element and the adjacent end of the shaft. In this way, the maximum extension of the transmission is distributed equally between the two joints and the shaft is constantly centered so that noise and wear of the check members is avoided. The invention is in particular applicable to transmissions for independent rear driving wheels of automobile vehicles.

Abstract: The process comprises placing on the journal the roller provided with its needles and the annular member for axially retaining the needles. Thereafter, one end of an elastically yieldable ring is engaged in a passageway provided on the journal and the ring is shifted along this passageway until it is completely received in a groove. This method is much more reliable and lends itself to a thorough automatization.

Abstract: The device comprises a resilient fastener which has branches clipped on a first of the two elements of the homokinetic joint and serves to hold the second element of the joint assembled with the first element. One of the branches of the resilient member carries an adjustable abutment device which cooperates with a second abutment device on the first element. The fastener can be made to exert a prestressing force by adjustment of the adjustable abutment device. The adjustable abutment device may be a screw which is screwthreadedly engaged in a nut carried by the corresponding branch of the fastener and has an abutment surface which abuts an abutment surface formed on the first element.

Abstract: In this device, which is particularly, but not exclusively, suitable for transmissions for vehicles, an elastomer protecting gaiter comprises a body connected by a fold to a mounting flange and by another fold to a neck portion. The latter comprises a ring forming a bearing, an arrangement for mounting the neck portion in a support, and a sealing device. The body of the gaiter is preferably rigid.

Abstract: The homokinetic transmission device is placed between a driving shaft and a driven shaft comprising two adjacent articulated joints. The articulated joints comprise a common intermediate member and are generally homokinetic and at least one of the joints is slidable. The arrangement of the two joints is adapted to permit a relative radial displacement between the two shafts. If h and l are the respective distances between the centers of the two adjacent tripod joints and the center of gravity of the transmission device interconnecting the two shafts, and .rho..sup.2 and Io/m, where Io represents the inertia of an intermediate member about an axis perpendicular to its general axis and to the direction of lateral displacement of said member and intersecting the center of gravity G, and where m represents the mass of the intermediate member, the following conditions are at least roughly satisfied:h.times.l=.rho..sup.2.

Abstract: The bearing comprises two rows of balls which circulate between two pairs of raceways. The raceways associated with each row of balls comprise two toric bearing surfaces which are substantially symmetrical with each other with respect to a plane perpendicular to the axis of rotation of the bearing. An elementary section of each of these bearing surfaces, in a plane containing the axis of the bearing, is at least substantially part-circular and has a radius slightly larger than the radius of the balls, and is substantially symmetrical with respect to a straight line parallel to the axis of the bearing and subtends a center angle exceeding about 120.degree.. The arrangement is such that the orientation of forces of contact and the location of zones of contact between the balls and the raceways vary in accordance with the direction of application of the load to which the bearing is subjected.

Abstract: The torque transmitting connecting element, for example constituted by a flange, comprises a small number of pairs of bearing planes which are angularly spaced apart. The two planes of each pair are convergent in a direction away from the connecting face of the element and constitute the two flanks of a channel or of a projection which has a constant trapezoid cross-sectional shape which is symmetrical relative to a plane containing the axis of rotation of the element. Such elements, when they are interconnected in a torque-transmitting device, cooperate solely by their pairs of bearing planes. Bolts or a nut clamp these two elements together.The invention is for example applicable to automobile vehicle transmissions.

Abstract: The method permits mass-producing axially retained tripod joints having high rigidity and a given prestressing force which is reproducible from one joint to another. According to this method, after having clipped a resiliently yieldable attachment onto a tulip-shaped element of the joint while the joint is in its assembled position, the value of the gap between the shoulder of a thrust member and a bearing surface of a hub carrying the trunnions is determined for the position of the joint in which the hub and tulip-shaped member are in alignment and the thrust member is axially shifted away from the hub and there is introduced in the gap produced between the thrust member and the hub a shim the thickness of which is chosen to be slightly larger than the gap.

Abstract: The two parts of the joint are axially retained by providing at least one intermediate element between the tripod element and the bell element of the joint. The intermediate element is connected to the bell element by a ball joint and allows a sliding of the tripod element in a direction perpendicular to the axis of the shaft rigid with the tripod element. This results in a longer life and an improved performance of the tripod joint.

Abstract: The joint comprises a tripod connected to one of the two shafts to be coupled by the joint and defining three trunnions on which three part-spherical rollers are mounted. A second member of the joint is connected to the other shaft and defines three raceways in which the rollers are received. The tripod constitutes a member which is distinct from the shaft associated with the tripod and is connected to this associated shaft by an auxiliary homokinetic coupling. The latter is capable of operating at an angle of displacement which is small relative to the maximum angle of displacement of the two shafts coupled by the joint.

Abstract: The joint comprises a first member defining a tripod connected to a first shaft and forming three trunnions. Part-spherical rollers are respectively slidably and rotatably mounted on the trunnions. A second member connected to a second shaft defines three raceways in which the rollers are received. The raceways are each formed by a pair of part-circular sectioned grooves the mean line of which is an arc of a circle centered preferably in the vicinity of the axis of the second shaft. The tripod is rigid with a shaft section which has, in a zone close to the tripod, a substantially triangular cross-sectional shape approximately constituting the envelope of the free edge of the second member when the joint operates with an angular displacement of the first and second shafts close to the maximum possible angle.

Abstract: At least one of the splined members of the splined coupling has its splines modified so that they have maximum thickness in an intermediate part of the splines and progressively decrease to the ends of the splines. The resulting profile is such that, upon application of a given torque, the pressure produced in the zones of contact between the interengaged splines is substantially constant throughout the interengaged length of the splines.