Abstract: A gripper for use in combination with a pin has a body having an axially open cavity in which the pin is engageable. Jaws in the cavity are radially displaceable between an inner holding position bearing radially inwardly on and gripping the pin and an outer release position in which the pin can be removed axially from the cavity. An actuating element in the body is engageable with the jaws and shiftable between end positions corresponding to the inner and outer positions of the jaws. An actuator connected to the actuating element can move it from one of the end positions into the other of the end positions. An externally accessible connecting or operating member on the chuck body is connected through an emergency release with the jaws for moving the jaws into the outer release position as the result of connection to or operation of the member.

Abstract: A steady rest has a body juxtposable with a workpiece rotatable about a workpiece axis. Two arm elements are pivoted on the body and carry outer rollers radially engageable with the workpiece. A center element shiftable on the body in a straight line generally radially of the axis carries a center roller engageable radially with the workpiece. The rollers are angularly spaced about the workpiece. An electric actuator mounted on the body is connected by a transmission to the elements for displacing the respective roller radially relative to the workpiece.

Abstract: The invention relates to a method of clamping a tool or a workpiece, using an electric actuator (1) having a housing (2) attached to a work spindle of a machine tool and in which a threaded spindle (3) for moving jaws of a chuck is axially displaceable, and an electric servomotor (4) having a rotor connected with a drive wheel (6) that moves a nut (7) on the threaded spindle (3), a first sensor being associated with the threaded spindle (3) for detecting the axial position thereof, and a second sensor being associated with the spindle nut (7) for detecting the axial position thereof, and including the method step of determining the position of the threaded spindle (3) by the first sensor when a slight axial force occurs due to contact of the clamping jaws with the tool or the workpiece, and continued movement of the spindle nut (7) until a specified sensor difference (12) between the first sensor and the second sensor is determined by the second sensor.

Abstract: A gripper for use in combination with a pin has a body having an axially open cavity in which the pin is engageable. Jaws in the cavity are radially displaceable between an inner holding position bearing radially inwardly on and gripping the pin and an outer release position in which the pin can be removed axially from the cavity. An actuating element in the body is engageable with the jaws and shiftable between end positions corresponding to the inner and outer positions of the jaws. An actuator connected to the actuating element can move it from one of the end positions into the other of the end positions. An externally accessible connecting or operating member on the chuck body is connected through an emergency release with the jaws for moving the jaws into the outer release position as the result of connection to or operation of the member.

Abstract: A chuck for a tubular body having a noncircular outer surface and an interior formed with a gripping formation has a spindle extending along an axis, axially displaceable claws in the spindle each having a pair of opposite ends, and a gripper head engageable with one of the ends of each of the claws in the spindle. This head is displaceable between a holding position in which the claws engage the gripping formation in the tubular-body interior and an open position disengaged from the gripping formation. The jaws move on displacement between the open position and the holding position by engagement of the gripper head with their one ends in a first pivotal movement and then at their other ends in a second pivotal movement to press their other ends against the working spindle.

Abstract: A device for clamping a stem has a body forming a piston chamber and having an axially outwardly open hole adapted to receive the stem and a plurality of collet jaws in the hole shiftable axially by a piston between an outer releasing position with its axial outer ends radially spread and an inner holding position with the ends more closely radially juxtaposed. The stem is engageable axially in the hole between the jaws and lockable in the body in the inner holding position. A main spring urges the piston and jaws axially inward into the inner position. A cover element has an outer head and is axially shiftable relative to the piston between an extended position with the head engaged radially between the outer ends of the jaws and a retracted position with the head spaced axially inward from the outer ends of the jaws.

Abstract: A steady rest has a body juxtposable with a workpiece rotatable about a workpiece axis. Two arm elements are pivoted on the body and carry outer rollers radially engageable with the workpiece. A center element shiftable on the body in a straight line generally radially of the axis carries a center roller engageable radially with the workpiece. The rollers are angularly spaced about the workpiece. An electric actuator mounted on the body is connected by a transmission to the elements for displacing the respective roller radially relative to the workpiece.

Abstract: The invention relates to a method for operating an actuation device (20), which is used to clamp and loosen a clamping device which comprises a tie bolt which can be adjusted in an axial manner in a machine spindle (3), for actuating a clamping head (6) which co-operates with clamping claws (5). Initially, force is exerted upon the tie bolt (4) by means of an actuation device (20) which is used to clamp in an axial clamping direction, until the axial length thereof is fixed in relation to the machine spindle (3) by means of self-locking. According to the invention, after self-locking is obtained, the effect of the force in the direction of clamping of the actuation element (20) on the tie bolt is stopped and remains blocked while the clamping device is being used, and to release clamping, the tie bolt (4) is displaced by the actuation device (20) in the direction of release which is counter to the clamping direction. The invention relates to a device for carrying out said method.

Abstract: The invention relates to an apparatus for holding a workpiece (2) or tool having a tapered collar (1) or the like and having a pull-back rod (4) axially shiftable in a body (3) for actuating a chuck head (6) cooperating with jaws (5). The axial position of the pull-back rod (4) is maintained in a holding position without utilizing the force of a tension spring by a self-locking mechanism.

Abstract: The invention relates to a method of clamping a tool or a workpiece, using an electric actuator (1) having a housing (2) attached to a work spindle of a machine tool and in which a threaded spindle (3) for moving jaws of a chuck is axially displaceable, and an electric servomotor (4) having a rotor connected with a drive wheel (6) that moves a nut (7) on the threaded spindle (3), a first sensor being associated with the threaded spindle (3) for detecting the axial position thereof, and a second sensor being associated with the spindle nut (7) for detecting the axial position thereof, and including the method step of determining the position of the threaded spindle (3) by the first sensor when a slight axial force occurs due to contact of the clamping jaws with the tool or the workpiece, and continued movement of the spindle nut (7) until a specified sensor difference (12) between the first sensor and the second sensor is determined by the second sensor.

Abstract: A chuck has a stationary support and a spindle rotatable in the support and having forward therefrom a forwardly open seat for a workpiece. A plurality of jaws are shiftable in the support to grip or release the workpiece. A pull rod coupled to the jaws projects rearward therefrom and carries a central plate. A rear plate spaced rearward of the central plate is rotationally fixed to the spindle. A push rod axially shiftable in the rear plate has a front end engageable with the central plate and a rear end projecting rearward from the rear plate. A spring braced between the spindle and the central plate urges the central plate rearward. A piston is shiftable in the support between a front position bearing forward opposite to the spring on the push rod and therethrough on the central plate and a rear position spaced rearward of the push rod.

Abstract: The invention relates to a tensioning device for a hollow shaft (1), comprising tensioning claws (3), which can be adjusted between a tensioned position, in which the tensioning claws (5) are engaged in the hollow shaft holder (7) having a tensioning structure (6), and an open position without engagement in the tensioning structure (6) by a tensioning head (5) guided axially displaceably in the working spindle (4). For the adjustment between the open position and the tensioned position, the tensioning claws (3) are displaceably supported in the working spindle (4) by the tensioning head (5) at the one end in a first pivot position and subsequently at the other end in a second pivot position.

Abstract: A device for clamping a stem has a body forming a piston chamber and having an axially outwardly open hole adapted to receive the stem and a plurality of collet jaws in the hole shiftable axially by a piston between an outer releasing position with its axial outer ends radially spread and an inner holding position with the ends more closely radially juxtaposed. The stem is engageable axially in the hole between the jaws and lockable in the body in the inner holding position. A main spring urges the piston and jaws axially inward into the inner position. A cover element has an outer head and is axially shiftable relative to the piston between an extended position with the head engaged radially between the outer ends of the jaws and a retracted position with the head spaced axially inward from the outer ends of the jaws.

Abstract: The invention relates to an apparatus for holding a workpiece (2) or tool having a tapered collar (1) or the like and having a pull-back rod (4) axially shiftable in a body (3) for actuating a chuck head (6) cooperating with jaws (5). The axial position of the pull-back rod (4) is maintained in a holding position without utilizing the force of a tension spring by a self-locking mechanism.

Abstract: The invention relates to a method for operating an actuation device (20), which is used to clamp and loosen a clamping device which comprises a tie bolt which can be adjusted in an axial manner in a machine spindle (3), for actuating a clamping head (6) which co-operates with clamping claws (5). Initially, force is exerted upon the tie bolt (4) by means of an actuation device (20) which is used to clamp in an axial clamping direction, until the axial length thereof is fixed in relation to the machine spindle (3) by means of self-locking. According to the invention, after self-locking is obtained, the effect of the force in the direction of clamping of the actuation element (20) on the tie bolt is stopped and remains blocked whilst the clamping device is being used, and to release clamping, the tie bolt (4) is displaced by the actuation device (20) in the direction of release which is counter to the clamping direction. The invention relates to a device for carrying out said method.

Abstract: A tool or workpiece has a mounting collar open axially outward, formed with a radially inwardly directed angled flank, and having a radial outer surface of noncircular cross-sectional shape. A chuck has a body formed with an axially forwardly open socket shaped to receive the collar with the axes generally coaxial and having an inner surface of a noncircular cross-sectional shape substantially complementary to the shape of the collar outer surface. A plurality of jaws axially fixed in the socket have radially movable ends engageable inside the collar and each formed with a radially inwardly and axially outwardly directed face. A cam having a face centered on the axis is engageable with the jaw front ends such that axial rearward shifting of the cam presses the jaw front ends outward and thereby presses the jaw faces against the collar flank to lock the collar in the socket.

Abstract: A chuck actuator has a hollow housing having a chamber and having a front end and a rear end. A ring in the chamber forms with the front end thereof a front compartment and a piston in the chamber between the ring and the rear end forms an intermediate compartment with the ring and a rear compartment with the rear end. A stem on the piston projecting forward through the ring and through the intermediate and front compartments is adapted to engage and open a chuck and is formed with a region of enlarged diameter. The piston is shiftable between a rear position with the enlarged-diameter region offset rearward from the ring and with the stem forming with the ring an axially extending passage between the front and intermediate compartments and a front position with the enlarged-diameter portion fitting snugly in the ring and substantially closing the passage.

Abstract: A holder for a collar having an axially forwardly directed shoulder and axially rearward thereof a radially outwardly directed centering surface has a drive sleeve fitted over the collar and a plurality of angularly spaced jaws each formed with an axially rearwardly directed face and displaceable between an outer position with their faces bearing on the shoulder and an inner position with their faces out of engagement with the collar. An axially displaceable actuating member can move the jaws between their inner and outer positions. A plurality of retaining fingers each have an axially rearwardly directed face and axially rearward thereof a radially outwardly directed centering face. These fingers are each radially elastically deformable between an outer position with the front-end faces bearing axially rearward on the shoulder and the centering faces bearing radially outward on the collar centering surface and an inner position out of contact with the collar.

Abstract: The invention relates to a clamping device arranged on a machine tool and used for a hollow shaft (2) provided with slanted clamping inclinations extending inside a receiving element for said hollow shaft (2), comprising clamping claws (6) which are mounted in the working spindle (5) of the machine tool, which can be actuated by means of a clamping head (3) which is guided in the working spindle (5) and which is axially displaceable therein and on which clamping inclinations (7), which have correspondingly slanted inclined surfaces (13) used for clamping purposes, come to rest.

Abstract: A chuck actuator has a hollow housing having a chamber and having a front end and a rear end. A ring in the chamber forms with the front end thereof a front compartment and a piston in the chamber between the ring and the rear end forms an intermediate compartment with the ring and a rear compartment with the rear end. A stem on the piston projecting forward through the ring and through the intermediate and front compartments is adapted to engage and open a chuck and is formed with a region of enlarged diameter. The piston is shiftable between a rear position with the enlarged-diameter region offset rearward from the ring and with the stem forming with the ring an axially extending passage between the front and intermediate compartments and a front position with the enlarged-diameter portion fitting snugly in the ring and substantially closing the passage.