To prevent a lowering of gripping force due to temperature changes, provided is a gripping mechanism including a plurality of chuck claws that, when having come close to each other, generate a gripping force on a gripped body; a chuck body that holds the plurality of chuck claws on a common planar surface, and moves them on the planar surface; and a plurality of chuck plates that, when each of the plurality of chuck claws grips the gripped body, are interposed between each of the plurality of chuck claws and the gripped body. A thermal expansion coefficient .sub.1 of the plurality of chuck claws, a thermal expansion coefficient .sub.2 of the plurality of chuck plates and a thermal expansion coefficient .sub.W of the gripped body have a relationship indicated by
.sub.W<.sub.1<.sub.2(Equation 1).

A multipurpose chuck having provisions for gripping the outer diameter of workpieces; alternatively, the inner diameter of workpieces; alternatively gripping parts by a two vise jaw, or in combination with a magnet attraction. The chuck having six radially movable jaws that can be used in combination, or by itself with vise grip jaws, which can be used in combination or by itself with a magnetic workpiece attachment in a single chuck.

A chuck device capable of efficiently changing a welding tip and nozzle. The chuck device includes a rotatable chuck base, an engagement part fixed to the chuck base so as to rotate integrally with the chuck base and can engage an engagement surface of the welding tip, the engagement part allowing the welding tip to rotate with the chuck base when the chuck base is rotated while engaged with the engagement surface, and a plurality of fingers provided to the chuck base to be openable and closable and can hold the welding tip and the nozzle, the plurality of fingers being capable of moving in directions approaching and separating from the engagement part.

A rotary chuck for processing wafer-shaped articles comprises a chuck body having a series of gripping pins that are movable by sliding horizontally and in unison relative to the chuck body from a first position in which the gripping pins are relatively more retracted into the chuck body to a second position in which the gripping pins are relatively more extended from the chuck body and in which the gripping pins are positioned so as to support a wafer-shaped article of a predetermined diameter.

An attachment apparatus for laser engraving comprising a chuck housing comprising a plurality of channels; a plurality of self-centering jaws bases disposed within the plurality of channels, the plurality of self-centering jaws bases further comprising at least one jaws base hole; and a scroll wheel in mechanical communication with the plurality of self-centering jaws bases.

A gripping mechanism includes: a plurality of chuck claws that, when having come close to each other, generate a gripping force on a gripped body; a chuck body that holds the plurality of chuck claws on a common planar surface, and moves them on the planar surface; and a plurality of chuck plates that, when each of the plurality of chuck claws grips the gripped body, are interposed between each of the plurality of chuck claws and the gripped body, wherein a thermal expansion coefficient .sub.l of the plurality of chuck claws, a thermal expansion coefficient .sub.2 of the plurality of chuck plates and a thermal expansion coefficient .sub.W of the gripped body has a relationship indicated by Equation 1:

.sub.W<.sub.1<.sub.2 (Equation 1)

A chuck for clamping workpieces or tools in a clamping space with a clamping force (F). The chuck includes at least two chuck jaws movable in translation along one clamping plane (E) in the direction of one center Z of the clamping space and a gear train located at least largely within the chuck for transfer of a driving torque of a drive motor, which can be coupled to the gear train by coupling means of the gear train, to the chuck jaws for movement of the chuck jaws. The coupling means able to be coupled to a corresponding coupling connection of the drive motor. The movement from the maximum size of the clamping space to the minimum size of the clamping space is executed via the gear train from the drive motor.

An attachment apparatus for laser engraving comprising a chuck housing comprising a plurality of channels; a plurality of self-centering jaws bases disposed within the plurality of channels, the plurality of self-centering jaws bases further comprising at least one jaws base hole; and a scroll wheel in mechanical communication with the plurality of self-centering jaws bases.

A chuck for gripping and moving cylindrical bodies, in particular fittings and pipe segments, including a main body defining an axis of rotation and a plurality of jaws fastened to the main body. The jaws are movable between a position of maximum closure, in which they are at the minimum distance from the axis of rotation, to a position of maximum opening, in which they are at the maximum distance from the axis of rotation. The chuck can adjust the positions of maximum closure and maximum opening and can move the jaws between the positions of maximum closure and maximum opening. The chuck also allows for the axial fixing of the chuck to a support member and for a connection of the chuck to the support member so that they are angularly rotatable with respect to each other.