A lathe capable of shortening a spindle with respect to a spindle axis direction. A spindle provided with a chuck at the front end thereof is rotatably supported on a support by bearings. A chuck operating apparatus includes a tilt claw and a shifter. A built-in motor is disposed between the bearings to rotate the spindle. The claw is provided outside the spindle and between the bearings. The claw has a movable end whose distance from the spindle axis varies between a first posture to bring the chuck into the opened state and a second posture to bring the chuck into the closed state. The shifter is provided outside the claw and movable in the spindle axis direction to be brought in a first position to bring the claw into the first posture and in a second position to bring the claw into the second posture.

A chuck device includes: a cylindrical chuck including a first contact part on a first side and a second contact part on a second side, and configured to hold a bar-like workpiece; a tubular outer cylinder including a restriction part configured to restrict axial movement of the chuck by abutting on the first contact part; and a sleeve provided in an axially movable manner on the inner peripheral side of the outer cylinder, and including, on the first side, a pressing part axially driven to abut on the second contact part. The chuck includes a first tapered face in the first contact part, and a second tapered face in the second contact part. A first angle between the first tapered face and a center axis is equivalent to a second angle between the first tapered face and the center axis, or is smaller than the second angle.

The invention relates to an axle arrangement (10) for mounting a tool or a workpiece. The axle arrangement (10) comprises a receiving unit (12) that is supported by a swivel bearing assembly (13) in a base body (11) so as to be rotatable about a longitudinal axis L. The receiving unit (12) has a receiving sleeve (18) that is supported so as to be immovable in longitudinal direction R parallel to the longitudinal axis L and has a gripper actuating element (23) that is supported so as to be slidable in the receiving sleeve (18) along the longitudinal axis L. On one end of the gripper actuating element (23) associated with the front end (18a) of the receiving sleeve (18), there is seated a gripper unit (24) for gripping the tool or the workpiece. The gripper unit (24) is pretensioned by a pretension unit (30) in a clamping position I. An actuatable release unit (34) can move the gripper unitcounter the pretension force FV of the pretension unit (30)into a release position II. By means of a support unit (48), an auxiliary bearing (49) that, in particular, is configured as an axial bearing, can be pressed against the receiving sleeve (18) in order to achieve an improved axial force support of the receiving unit (12) on the base body (11) and to reduce the load on the swivel bearing assembly (13) due to axial forces.

A chuck device includes a chuck main body, an exchange member, an axial direction regulating mechanism, and a circumferential direction regulating mechanism. The axial direction regulating mechanism has a circumferential groove section, which extends in the circumferential direction, that is recessed into one of the chuck main body and the exchange member and a radially protruding section, which is able to protrude in the radial direction, that is disposed in the other of the chuck main body and the exchange member. The circumferential direction regulating mechanism has an axially recessed section, which is recessed in the axial direction, that is disposed in one of the chuck main body and the exchange member and an axially protruding section, which is able to protrude in the axial direction, that is disposed in the other of the chuck main body and the exchange member.

A chuck device includes: a cylindrical chuck including a first contact part on a first side and a second contact part on a second side, and configured to hold a bar-like workpiece; a tubular outer cylinder including a restriction part configured to restrict axial movement of the chuck by abutting on the first contact part; and a sleeve provided in an axially movable manner on the inner peripheral side of the outer cylinder, and including, on the first side, a pressing part axially driven to abut on the second contact part. The chuck includes a first tapered face in the first contact part, and a second tapered face in the second contact part. A first angle between the first tapered face and a center axis is equivalent to a second angle between the first tapered face and the center axis, or is smaller than the second angle.

Disclosed is a system to engage a plurality of tools. In the system a drive shaft and collet may be assembled to engage and disengage, selectively, a plurality of tools. User selection may allow use of a plurality of tools during a procedure or during a plurality of procedures.

A balancing or measuring adapter, which includes a main body having a holder for the component to be balanced or measured and a clamping device assigned to the main body having a movable clamping element for clamping the component to the main body and releasing it therefrom. A braking device for generating a constant advance speed of the clamping element as it moves is arranged on the movable clamping element for precisely positioned clamping and jerk-free release of the component.

A guide bush control device includes a guide bush motor that rotates and drives a guide bush; and a controller that controls driving of the guide bush motor, the guide bush control device controlling rotation of the guide bush by controlling the driving of the guide bush motor with the controller, wherein the controller includes a fixing unit that fixes the guide bush non-rotatably by exciting the guide bush motor in a rotation stop state.

An improved spindle assembly for a Davenport multi-axis screw machine is adapted to adequately hold one-inch round bar-stock in a collet against movement relative thereto attributable to machining operations performed on a cantilevered length of bar-stock held in and extending beyond the collet. The spindle assembly may permit the use of the screw machine on materials thought heretofore to be too difficult to machine on a screw machine. Cam surfaces on the inner spindle and collet may be coated with a low-friction material. A stress-relieving connection between the inner spindle and collet is provided.

A guide bush adjusting device includes a drawbar (a mobile body) displaceable relative to a guide bush sleeve (cylindrical body). The drawbar is formed from a screw connection member (a connection member) which is connected to a guide bush housed in the guide bush sleeve (a cylindrical body), and an operation member configured to displace the screw connection member. The guide bush adjusting device adjusts an inner diameter of the guide bush by releasing the operation member from its fixation, displacing the drawbar, moving the guide bush with respect to the guide bush sleeve via the drawbar to thereby position the guide bush, and fixing the operation member of the drawbar (mobile body) at a predetermined position.