A tap holder having a simple structure and high runout accuracy is provided. A tap holder includes: a body having a collet holder hole having an opening toward distal end; a tap collet received in the collet holder hole, the tap collet having a tap mounting hole located at a distal end portion, and a sleeve hole located at a basal end portion; a torque transmission mechanism that transmits rotation of the body to the tap collet; a first elastic body disposed between the body and the tap collet to urge the tap collet toward distal end; a sleeve disposed to the body by received in the sleeve hole to prevent the tap collet from slipping off toward distal end; and a second elastic body disposed between the sleeve and the tap collet to urge the tap collet toward basal end.

The present invention provides a lathe having a speeder device to increase the speed of a workpiece to be worked on by the lathe as compared to the speed of a workpiece to be worked on by the lathe without the use of the speeder device. The speeder device includes a torque arm, a means for stopping rotation of the torque arm, a planetary gearset assembly, an output spindle assembly, and a collet assembly. The means for stopping rotation of the torque rod is secured to a first end of the torque rod and the planetary gearset assembly is operatively connected to a second end of the torque rod. The output assembly is operatively connected to the planetary gear assembly, and the collet assembly holds the workpiece and is operatively connected to the spindle assembly.

A clamping device for a tool or workpiece has a draw-in collet and a coupling element. The clamping device has first and second bayonet closures with which the draw-in collet can be locked and braced against the coupling element. The first and second bayonet closures are brought into engagement at the same time, as a result of which the draw-in collet is locked against the coupling element using the first bayonet closure, and the draw-in collet is braced against the coupling element using the second bayonet closure. First, the draw-in collet is pushed into the coupling element with partial actuation of the bayonet closures. Then the draw-in collet is rotated relative to the coupling element with a further partial actuation of the bayonet closures, and finally the draw-in collet is withdrawn to thereby lock the first bayonet closure and to brace the second bayonet closure.

A clamping device for a tool or workpiece has a draw-in collet and a coupling element. The clamping device has first and second bayonet closures with which the draw-in collet can be locked and braced against the coupling element. The first and second bayonet closures are brought into engagement at the same time, as a result of which the draw-in collet is locked against the coupling element using the first bayonet closure, and the draw-in collet is braced against the coupling element using the second bayonet closure. First, the draw-in collet is pushed into the coupling element with partial actuation of the bayonet closures. Then the draw-in collet is rotated relative to the coupling element with a further partial actuation of the bayonet closures, and finally the draw-in collet is withdrawn to thereby lock the first bayonet closure and to brace the second bayonet closure.

A rapid change chuck adapter system includes a chuck adapter that is removably attachable to the chuck in place of removed chuck teeth. The chuck adapter is operable to engage a collet such that an operation of the chuck as if the chuck teeth were not removed operates the collet via the chuck adapter.

A tool holder (1) includes a clamping member (4) for clamping and holding a tool (5), a holder body (2) having, at a leading end thereof, a receiving portion (25) for receiving the clamping member (4) along an axis (AX) and an operational member (N) for attaching the clamping member (4) to the holder body (2). The clamping member (4) clamps the tool (5) by an operation of the operational member (N). Vibration is applied to a contact portion (T) between the clamping member (4) and the holder body (2) when the clamping member (4) clamps the tool (5).

A tool holder (1) includes a clamping member (4) for clamping and holding a tool (5), a holder body (2) having, at a leading end thereof, a receiving portion (25) for receiving the clamping member (4) along an axis (AX) and an operational member (N) for attaching the clamping member (4) to the holder body (2). The clamping member (4) clamps the tool (5) by an operation of the operational member (N). Vibration is applied to a contact portion (T) between the clamping member (4) and the holder body (2) when the clamping member (4) clamps the tool (5).

Clamping device having a receiving opening which is arranged concentrically to a workpiece spindle axis, wherein the clamping device is designed for clamping a gear workpiece comprising a head region and a shaft, the clamping device comprises an annular planar contact surface, which is arranged concentrically to the workpiece spindle axis, is located in a workpiece-side end region of the clamping device, and which extends essentially perpendicular to the workpiece spindle axis, wherein at least one circumferential groove is provided in the workpiece-side end region, which groove extends from an outer surface of the clamping device radially in the direction of the workpiece spindle axis and which provides the clamping device with elasticity in the region of the planar contact surface.

A positioning cutter/collet assembly has a cutter/collet and a magnetic attracting position key. The cutter/collet has a cutter/collet key seat recessed in an external annular surface thereof. The magnetic attracting position key is mounted on and magnetically attracts the cutter/collet key seat. The magnetic attracting position key has a body having a protruding rod and a magnetic attracting portion combined with the body and magnetically attracting the cutter/collet to prevent the magnetic attracting position key from separating from the cutter/collet.

A positioning cutter/collet assembly has a cutter/collet and a magnetic attracting position key. The cutter/collet has a cutter/collet key seat recessed in an external annular surface thereof. The magnetic attracting position key is mounted on and magnetically attracts the cutter/collet key seat. The magnetic attracting position key has a body having a protruding rod and a magnetic attracting portion combined with the body and magnetically attracting the cutter/collet to prevent the magnetic attracting position key from separating from the cutter/collet.