Abstract: The invention provides an expanding mandrel comprising a shaft (1) having a conical forward end (10), an expanding sleeve (5) constituted by a ring provided with longitudinal slits designed to slide over said conical forward end (10), the inner wall of said sleeve (5) itself also having the shape of a cone the apex angle of which is equal to that of the conical forward end (10), and a tie member (2) designed to be connected to a rod that can be caused to slide along the axis of the machine spindle to control the gripping or the release of a workpiece. According to the invention, the sleeve (5) is connected to said tie member (2) via a control ring (3) integral with the tie member (2), and the mandrel comprises a removable quick mounting means enabling the sleeve (5) to be secured to said control ring (3).

Abstract: The invention provides a mandrel comprising a shaft (1) the forward end of which has the shape of a forward pointing truncated cone (7), an expanding sleeve (15) constituted by a ring provided with longitudinal slits designed to slide over said conical forward end (7), and a piston (8) which is guided in a cylindrical bore provided along the axis of the mandrel shaft (1), from which it projects forwards, with the sliding of said piston (8) driving said sleeve (15) so as to control the gripping or the releasing on said mandrel of a workpiece to be machined.

Abstract: The clamping chuck comprises six jaw carrier arms (4) that are operated two by two by one and the same compensator (5). Each compensator hinges with a pulling member (3) centered on the axis of the chuck and sliding axially in its main body (1) through the action of a traction rod (11). The pulling member is provided with pairs of wings (14a, 14b) extending on either side of the central portion of the compensator (5). Application to clamping chucks for high speed machining.

Abstract: The invention provides a chuck including a plurality of jaws (8), each of which is fixed to the forward end of a jaw carrier arm (5), said arm (5) being borne by a pivot joint (6) mounted on the body (1) of the chuck and the rotation of which imparts to the jaw (8) an essentially radial movement, said rotation being controlled by radially displacing a sliding member (4) pushing a truncated sphere (10) housed between said sliding member (4) and a recess provided in the arm (5) to the rear of said pivot joint (6). Furthermore, said truncated sphere (10) is capable of sliding over the plane surface of contact with the sliding member (4), said jaw carrier arm (5) then sliding in the pivot joint (6) in an essentially axial direction, while being drawn rearwards by a return spring (7). Application to the clamping of a piece while pressing it axially against its stops.

Abstract: Clamping is ensured by at least two pivoting arms one end of which co-operates with a half draw member (10a, 10b) via a link having a truncated sphere (19) and an inclined plane (10). The draw member is mounted coaxially outside a locking ring (9) displaceable through the action of a traction rod (5). The system of transmission between the ring and the draw member is provided with compensating and locking means constituted by a guide (11), a compensating disk (13) and an adjusting member (14) co-operating with an oblique face of the compensating disk.

Abstract: This invention relates to a gripping jaw (1) comprising: a body (4); a traction rod (6) sliding axially in the body (4); at least one jaw holder (3) sliding radially in the body (4); and a transmission system (7,8) converting axial translation of the traction rod (6) into the radial translation of each jaw holder (3). Each jaw holder (3) is fitted with a guiding member (10) guided radially along a groove (14) recessed within the chuck (1), the member being uniquely free to swivel axially in relation to the jaw holder.

Abstract: A system is provided for the rapid change, among others, of clamping jaws on a machine-tool which comprises self-blocking means for locking a jaw for clamping a workpiece from the inside or a jaw for clamping a workpiece from the outside. The jaw-holder is provided with at least two bearing portions for said jaws, the bearing faces being slanted through an angle .alpha. and .gamma. respectively. These faces cooperate in the blocked position with corresponding bearing faces of the jaws. One of the ends of an assembly has a face slanted through an angle .beta. whereas another face is slanted through an angle .delta.. These faces cooperate in the blocked position with a corresponding bearing face respectively of one of the jaws.

Abstract: An exchange mechanism enables removable members such as a tool member to be secured to an irremovable machining center. The exchange mechanism comprises a cassette connectible to the tool member, and a plurality of locking members and associated actuator carried by the machining center. The actuator slides the locking members radially outwardly such that inclined faces on the locking members abut corresponding inclined faces on the cassette. The inclined faces are oriented such that a force is exerted on the cassette which has an axial component urging the cassette toward the machining center, and a radial component tending to center the cassette.

Abstract: A quick clamping jaw change system comprises a blocking element on which a jaw is to be mounted. The blocking element carries a spring-biased pusher having an inclined pusher face which pushes against the jaw to displace the jaw against an inclined bearing face of the blocking member. Accordingly, the jaw slides along the bearing face to a locked position against the blocking element. The angle of inclination of the bearing face is larger than that of the pusher face so that the jaw cannot become dislodged unless the pusher is retracted against its spring bias.

Abstract: A chuck having a plurality of elastic and resilient compressible segments which have the general shape of a strip which, in longitudinal section, have a zig-zag configuration with flattened tops and bottoms, with upper and lower recesses which are filled with an elastomeric material.

Abstract: A mechanism for transforming a translation movement into a rotation movement which is then followed by a translation movement comprising a first member which can be a control member slidable on a smooth shaft and constituted by a hollow cylinder coaxial with the shaft, and terminated by two planar symmetrical faces which are inclined with respect to the shaft, and a second member which can be a driven member and fixed to the shaft. The second member is constituted by two hollow cylinders coaxial with the shaft and of the same diameter as the control member. Each hollow cylinder terminates with a planar face having the same inclination with the shaft as the faces of the control member, the planar faces of the hollow cylinders being in contact with respective faces of the control member. The two planar faces of the driven member are angularly offset relative to one another.