A clamping device for releasably holding a tool holder shank is formed with an engagement bore in a rear end. The clamping device includes a housing having a mounting bore for receiving the tool holder shank; a drawbar being mounted reciprocally movable inside the housing and which in a forward end is provided with an engagement segment which is arranged to engage with an engagement formation inside the engagement bore of the tool holder shank, wherein the drawbar is in a rear portion formed with a drawbar aperture extending through the drawbar, and a cam shaft extending through the drawbar aperture and comprising a cam formation. The cam shaft is rotatably journalled in the housing and arranged to impart an axial displacement to the drawbar in relation to the housing by the cam formation when rotating the cam shaft. The cam shaft includes two identical cam formations, which are spaced apart by a recess, and the drawbar is on the inside of the aperture formed with a ridge on each side of the aperture which each fits in the recess of the cam shaft when rotating the same.

Provided is a main spindle mechanism for a machine tool such that even in the case of a small-diameter spindle, it is possible to increase the torque transmitted to a large cutter and it is possible to prevent contact to and collisions with the workpiece. The main spindle mechanism, which is provided to a machine tool that cuts a workpiece by means of a cutter, is characterized by having: a spindle that transmits torque from the drive power source of the machine tool and is formed with outer teeth at the outer periphery of the tip thereof; a large cutter arbor provided with a shaft for attaching the large cutter and a base at which outer teeth are formed having the same diameter as the outer teeth of the spindle; and a gear-coupling-shaped sleeve that is provided in a manner so as to cover the base of the large cutter arbor and the tip of the spindle, and at which are formed inner teeth that mesh with both the outer teeth of the spindle and the outer teeth of the large cutter arbor.

A system and method can support in-memory session replication in a server cluster using a lazy deserialization approach. The server cluster can include a primary application server and a secondary application server. The primary application server operates to receive a request associated with a session from a client and maintains session information associated with the session. Based on the session information, the primary application server can responds to the client. The secondary application server operates to receive and maintain serialized session information from the primary application server. The secondary application server operates to update the serialized session information based on one or more session updates received from the primary application server. When the primary application server fails, the secondary application server can generate deserialized session information based on the updated serialized session information and responds to the client.

Disclosed is a mounting device (6) including a receiving opening (8) with a circular inner locating surface (10) which is coaxial with the axis of rotation (3) and serves for engagement with radially outer vertices (24) of the polygon profile of a holding pin (23). Arranged adjacent to the inner locating surface is a positioning disk (14) which has an opening (15) coaxial with the axis of rotation (3) and of such polygonal shape and size that the polygon profile of the holding pin (23) engaging in the opening (15) is supported in the opening (15) in a manner preventing relative rotation.

The whirling device comprises a retaining ring extending around a ring axis and a central opening and having at least one receiving area for a machining element for machining rod-shaped material in the area of the central opening. A coolant supply comprises a supply sleeve which is arranged on the retaining ring via a rotary bearing and comprises a coolant connection and a supply area adjoining a connection area of the retaining ring. Starting from at least one inlet opening in the connection area of the retaining ring, at least one passage leads through the retaining ring to at least one outlet opening which faces the central opening of the retaining ring and is designed for a machining element in a receiving area. No space is required for the coolant supply between the retaining ring and an assigned lathe.

Portable milling machine having a housing, a spindle and a clamping nut, which, as part of a tool holder, can be rotatably connected to the spindle and detached therefrom in order to clamp and unclamp a milling tool, and the portable milling machine having a spanner, which can be moved relative to the spindle axially between an engaged position and a disengaged position, the spanner interlockingly surrounding the clamping nut at least in portions in the circumferential direction in the engaged position and, when the spanner is in the disengaged position, the clamping nut being rotatable relative to the spanner, the spanner being connected to the housing of the portable milling machine for conjoint rotation such that, when the spanner is in the engaged position, the clamping nut can be connected to the spindle and detached therefrom by manually rotating the spindle.

A keyless chuck for attaching a tool bit to a power tool includes a knob having a central aperture and defining a longitudinal axis, a hub within the central aperture and configured to attach to the power tool, and a collet within the hub and having a receiving end configured to receive the tool bit. The knob is adjustable between a locked position in which a clamping force is applied to the collet to retain the tool bit therein, and an unlocked position in which the clamping force is relieved to permit removal of the tool bit.

Portable milling machine having a housing, a spindle and a clamping nut, which, as part of a tool holder, can be rotatably connected to the spindle and detached therefrom in order to clamp and unclamp a milling tool, and the portable milling machine having a spanner, which can be moved relative to the spindle axially between an engaged position and a disengaged position, the spanner interlockingly surrounding the clamping nut at least in portions in the circumferential direction in the engaged position and, when the spanner is in the disengaged position, the clamping nut being rotatable relative to the spanner, the spanner being connected to the housing of the portable milling machine for conjoint rotation such that, when the spanner is in the engaged position, the clamping nut can be connected to the spindle and detached therefrom by manually rotating the spindle.

The present invention relates to a rotary cutting tool assembly comprising a toolholder which has a central tool holding receptacle, and a cutting tool which has a holding projection that can be detachably held in the tool holding receptacle and via which the cutting tool is secured to and radially centered on the tool, wherein the holding projection has at its free end a pin-like, first centering section and an adjoining externally threaded section, wherein the holding projection ends in a radially outwardly projecting shoulder having an end face abutment surface, and the tool holding receptacle has an internally threaded section for receiving the externally threaded section and a first centering seat section which is positioned deeper within the tool holding receptacle and in which the centering section of the cutting tool is held.

A keyless chuck for attaching a tool bit to a power tool includes a knob having a central aperture and defining a longitudinal axis, a hub within the central aperture and configured to attach to the power tool, and a collet within the hub and having a receiving end configured to receive the tool bit. The knob is adjustable between a locked position in which a clamping force is applied to the collet to retain the tool bit therein, and an unlocked position in which the clamping force is relieved to permit removal of the tool bit.