In a working machine, left and right side walls are erected on a bed, a forward/backward saddle is movable in forward/backward directions, left and right sides of the forward/backward saddle are movably supported with the left and right side walls, a forward/backward drive device is arranged on the left and right side walls, to move the forward/backward saddle in the forward/backward directions, a left/right saddle is arranged on the forward/backward saddle and movable in left/right directions, a left/right drive device is arranged on the forward/backward saddle on each of forward/backward sides of the left/right saddle, to move the left/right saddle in the left/right directions, an up/down slider is movable up and down and arranged on the left/right saddle, a lower portion of the up/down slider is provided with a processing head to which a processing tool for processing a work set on the bed is removably and replaceably attached.

In a working machine, left and right side walls are erected on a bed, a forward/backward saddle is movable in forward/backward directions, left and right sides of the forward/backward saddle are movably supported with the left and right side walls, a forward/backward drive device is arranged on the left and right side walls, to move the forward/backward saddle in the forward/backward directions, a left/right saddle is arranged on the forward/backward saddle and movable in left/right directions, a left/right drive device is arranged on the forward/backward saddle on each of forward/backward sides of the left/right saddle, to move the left/right saddle in the left/right directions, an up/down slider is movable up and down and arranged on the left/right saddle, a lower portion of the up/down slider is provided with a processing head to which a processing tool for processing a work set on the bed is removably and replaceably attached.

Provided is a clamp device of an indexing apparatus that indexes a main shaft, which is rotatably supported in an accommodation hole of a frame via a bearing, to a set angular position by rotating the main shaft by using a driving device. The clamp device includes a working channel that connects an air supply device, which supplies compressed air, to a pressure chamber in the clamp device. The clamp device operates to retain an angular position of the main shaft when compressed air is supplied from the air supply device. The clamp device includes a pressure transmitting portion that is interposed in the working channel and in which a piston is slidably disposed. A portion of the working channel on the pressure chamber side of the piston in the pressure transmitting portion is filled with an incompressible fluid.