Abstract: To provide a machine tool of which the operation rate can be increased by reducing time for suspending an operation for machining an object to be machined during the object-machining operation using the machine tool. A jig includes at least a first jig (5) disposed in a casing (2) and a second jig (14) by which an object (8) is detachably held. The jigger has attaching/detaching structure (17) for detachably mounting the second jig (14) onto the first jig (5). The second jig (14) is provided with grip parts (32) for gripping the second jig (14) during its movement.

Abstract: There is provided a workpiece support device for use in machining a workpiece including: a securing support unit; and a following support unit. The securing support unit has a securing abutment member releasably positioned and secured at a desired position, and the securing abutment member abuts against the workpiece at a portion near a portion to be machined to prevent said portion to be machined from moving against the secured securing abutment member. The following support unit has a following abutment member, and the following abutment member abuts against the workpiece at a portion near the portion to be machined on the same side as the securing abutment member, is movable following a movement of the workpiece, and applies a pressure to the workpiece during the movement.