Abstract: There is provided a multi-layered circuit board and a manufacturing method of the multi-layered circuit board that allows electronic parts to be mounted adequately and that will not hamper performance of the electronic parts. A power terminal (pin) of an electronic part to be mounted on a surface of the multi-layered circuit board is inserted into a plated through hole to connect with a first conductive layer. A detecting section having a detecting hole which is formed coaxially with the through hole and whose diameter is larger than the through hole is provided on a second conductive layer on the back of the first conductive layer. A hole having a large diameter is formed by a tool along the through hole from the back while applying voltage between the second conductive layer and the tool. A depth of the hole is set based on that the tool electrically conducts with the detecting hole. Unnecessary plate of the through hole may be removed by the large hole.

Abstract: The invention provides an active mass damper by use of which a machining apparatus can be downsized. The active mass damper includes a support unit for supporting a weight movably and horizontally, a motor for driving the weight, and a controller for controlling the motor. A torque command signal to be given to a motor of an X-table and a torque command signal to be given to a motor of a Z-table are put into the controller of the active mass damper so that the motor for driving the weight can be driven by feed-forward control using the torque command signals and feedback control based on the displacement of the weight.

Abstract: The invention provides an active mass damper by use of which a machining apparatus can be downsized. The active mass damper includes a support unit for supporting a weight movably and horizontally, a motor for driving the weight, and a controller for controlling the motor. A torque command signal to be given to a motor of an X-table and a torque command signal to be given to a motor of a Z-table are put into the controller of the active mass damper so that the motor for driving the weight can be driven by feed-forward control using the torque command signals and feedback control based on the displacement of the weight.