The present disclosure provides a jaw assembly for mounting to a lathe spindle. The jaw assembly comprises a first jaw set with at least one axially extending jaw portion which comprises a channel extending in the same axial direction as the jaw portion, and a second jaw set locatable within and releasably attached to the first jaw set via at least one fastener locatable in the channel.

A chuck (1) is provided by means of which workpieces (2) are supported individually for machining by a machine tool (3) and aligned coaxially to a centering axis (4), which serves as a reference for machining the workpiece (2) by the machine tool (3), having a chuck body (5), having at least four clamping jaws (6, 7, 8, 9) that are radially movably mounted on the chuck body (5) and are arranged in pairs in an X or Y plane and by means of which the workpiece (2) is held during the machining process to be aligned with respect to the centering axis (4), and having a pull piston (45) that is mounted in or at the chuck body (5) so as to be linearly movable and which is drivably coupled to a respective clamping jaw (6, 7, 8, 9) such that during the linear movement of the pull piston (45) the clamping jaws (6, 7, 8, 9) are radially fed in the direction of the workpiece (2) to be clamped or moved away from same in a synchronous manner, wherein the pull piston (45) is arranged coaxially with respect to the centering axis (4) inside the chuck body (5) and is axially actuated by one or more drive means (12, 13, 52, 53), on the one hand aiming at adjusting the compensatory movements between two adjacent clamping jaws running perpendicular to one another (6, 7, 8, 9) irrespective of their feed movement and operative contact with the workpiece (2) to be clamped, and on the other hand aiming at the constructional height of such chuck (1) being as small as possible. This aim is achieved in that each drive means (12, 13, 52, 53) has a linearly movable piston rod (26) or threaded spindle (55), whose respective longitudinal axis (26′ or 55′) is arranged to be perpendicular to the centering axis (4). (FIG. 1)

A power chuck includes a housing in which there is arranged a drive unit having a traction guide means moveable in the direction of a clamping axis. There, and there are arranged two pairs of mutually diametrically opposite base jaws. The base jaws are guided radially, in the housing substantially perpendicularly to the clamping axis, and the drive unit is adapted to convert the movement of the traction guide means into the movement of the base jaws. According to the invention, it is proposed that the drive unit for each base jaw has a slider which is in engagement with the base jaw and which is moveable with a movement component on a circular path about the clamping axis.

The invention relates to a chuck (1) via which workpieces (2) are supported on a machine tool in a separate and centered manner for machining by the machine tool, including a chuck body (3) and at least four radially oriented guide grooves (4) that are incorporated into same, including at least four clamping jaws (5, 6, 7, 8) that are situated in each case in pairs in an x or y plane, and separately inserted into one of the guide grooves (4) in a movably supported manner, including a drive element (9) that is mounted in the chuck body (3), and which synchronously feeds the four clamping jaws (5, 6, 7, 8) in the direction of the workpiece (2) to be clamped or is moved away by same, and including a rocker (11) that is provided in each case between the drive element (9) and two adjacent clamping jaws (5, 7 or 6, 8), the rocker having a center of symmetry (12) into which a bolt (13) that is swivelably mounted on the drive element (9) is inserted, the rocker (11) being swivelable about the bolt as a function of the contact of the clamping jaws (5, 6 or 7, 8) with the workpiece (2). According to the invention, movement compensation is to take place between two adjacent clamping jaws (5, 6, 7, 8), via which the various clamping jaws (5, 6, 7, 8) are quickly exchangeable without uninstalling the chuck body (3). This is achieved by providing a wedge rod (31) and/or a drive ring, which in each case are/is drivingly coupled to the drive element (9) and one of the clamping jaws (5, 6, 7, 8), between the drive element (9) and one of the chuck jaws (5, 6, 7, 8).

In a chuck (1) by means of which workpieces (2) are supported individually and centered for machining by a machine tool, the chuck comprising: a chuck body (3), four clamping jaws (5, 6, 7, 8) which are radially movably mounted on the chuck body (3) and are each arranged in pairs in an X or Y plane, and a drive piston (9) which is mounted in the chuck body (3) so as to be axially movable and which is drivably coupled to the four clamping jaws (5, 6, 7, 8) via a helical surface or helical gearing (10) worked on the drive piston (9) and the respective clamping jaws (5, 6, 7, 8), and feeds these synchronously in the direction of the workpiece (2) to be clamped or moves them away from the latter, a position-accurate, i.e. centered alignment for a large number of differently designed workpieces (2) can be achieved with a high repetition accuracy for subsequent clamping operations. This is achieved in that a rocker (11) is provided between the drive piston (9) and two adjacent clamping jaws (5, 7 or 6, 8), the rocker (11) has a center of symmetry (12) into which a bolt (13) which is pivotably mounted on the drive piston (9) and about which the rocker (11) can be pivoted as a function of the contact of the clamping jaws (5, 6 or 7, 8) on the workpiece (2) is inserted, and a corresponding transmission pin (14, 15) is provided laterally adjacent to the bolt (13) and coupled drivably to the rocker (11), the respective clamping jaw (5, 6, 7, 10 or 8) being mounted and supported at the end of the transmission pin opposite the rocker (11).

A rim drilling and milling machine has a base (10), a column (20), a turret (30), a saddle (40), a table (50), and a fixture unit (60). The fixture unit (60) has a foundation (61) and four clamping seats defined as two first clamping seats (63A) and two second clamping seats (63B). The first clamping seats (63A) are slidably mounted on the foundation (61) along a first radial direction, and are disposed at positions diametrically opposite in the first radial direction. The second clamping seats (63B) are slidably mounted on the foundation (61) along a second radial direction perpendicular to the first radial direction, and are disposed at positions diametrically opposite in the second radial direction. The four clamping seats can clamp at four equiangular points of a wheel rim.

In a chuck (1) by means of which workpieces (2) are supported individually and centered for machining by a machine tool, the chuck comprising: a chuck body (3), four clamping jaws (5, 6, 7, 8) which are radially movably mounted on the chuck body (3) and are each arranged in pairs in an X or Y plane, and a drive piston (9) which is mounted in the chuck body (3) so as to be axially movable and which is drivably coupled to the four clamping jaws (5, 6, 7, 8) via a helical surface or helical gearing (10) worked on the drive piston (9) and the respective clamping jaws (5, 6, 7, 8), and feeds these synchronously in the direction of the workpiece (2) to be clamped or moves them away from the latter, a position-accurate, i.e. centered alignment for a large number of differently designed workpieces (2) can be achieved with a high repetition accuracy for subsequent clamping operations.

This is achieved in that a rocker (11) is provided between the drive piston (9) and two adjacent clamping jaws (5, 7 or 6, 8), the rocker (11) has a center of symmetry (12) into which a bolt (13) which is pivotably mounted on the drive piston (9) and about which the rocker (11) can be pivoted as a function of the contact of the clamping jaws (5, 6 or 7, 8) on the workpiece (2) is inserted, and a corresponding transmission pin (14, 15) is provided laterally adjacent to the bolt (13) and coupled drivably to the rocker (11), the respective clamping jaw (5, 6, 7, 10 or 8) being mounted and supported at the end of the transmission pin opposite the rocker (11).

A compensating chuck for concentrically clamping workpieces. The chuck has a drive unit having two pairs of entrainment members, wherein the entrainment members are preferably slidingly mounted, are respectively movable in paired relationship, and are so coupled to a respective one of the main jaws that a relative movement of a respective pair causes a synchronous movement of adjacent main jaws and that both a relative movement relative to each other with respectively different movement components and also a synchronous movement of the adjacent entrainment members in the same direction respectively causes a relative movement of adjacent main jaws.

A power chuck includes a housing in which there is arranged a drive unit having a traction guide means moveable in the direction of a clamping axis. There are arranged two pairs of mutually diametrically opposite base jaws. The base jaws are guided radially, in the housing substantially perpendicularly to the clamping axis, and the drive unit is adapted to convert the movement of the traction guide means into the movement of the base jaws. According to the invention, it is proposed that the drive unit for each base jaw has a slider which is in engagement with the base jaw and which is moveable with a movement component on a circular path about the clamping axis.

A compensation chuck for centrically clamping workpieces includes a housing, two pairs of mutually diametrally opposite base jaws for receiving corresponding clamping jaws, and a drive unit which is moveable preferably by power clamping having two pairs of drivable entrainment members. Two adjacent entrainment members are respectively coupled together by a first rocker and two further adjacent entrainment members are coupled together by a second rocker. There is also provided a coupling ring which guides a first entrainment member and a diametrally opposite second entrainment member in the peripheral direction tangentially relative to the clamping axis, such that a motion play is provided between the entrainment members and the coupling ring in the radial direction.