Chuck

A chuck, comprising:

• a sleeve;
• a chuck body rotatably disposed in the sleeve, wherein a longitudinal axis is defined extending along the direction of the chuck body, and wherein the chuck body has a first shaft cavity for receiving a tool bit;
• a plurality of chuck jaws configured to be distributed in the chuck body about the longitudinal axis, wherein the plurality of chuck jaws are configured to be movable relative to the chuck body to clamp or release the tool bit;
• an adjusting mechanism disposed between the sleeve and the chuck jaws being configured to adjust relative displacement between the chuck jaws and the chuck body;
• wherein the chuck further comprising at least one locating member being disposed between adjacent chuck jaws in the chuck body and a pushing mechanism, when the adjusting mechanism drives the chuck jaws moving close to the longitudinal axis, the locating member is driven by the pushing mechanism to move toward the longitudinal axis, and wherein the tool bit is held by the locating member before the tool bit is clamped by the chuck jaws;
• and
• when the adjusting mechanism drives the chuck jaws moving away from each other along the longitudinal axis, the locating member is driven by the pushing mechanism to move away from the longitudinal axis.