To detect a collision at high sensitivity without limiting the collision direction by detecting the displacement of a contact sensing member arranged on an attachment to be connected to a main shaft sleeve or a main shaft end, and transmitting a contact signal to a controller by a radio signal.
When the position of a stylus is displaced after the stylus of a main shaft unit is brought in contact with a work piece by reckless driving of a machine tool, an oscillating member 105 connected to a connecting part of the stylus is oscillated or moved in the lateral and axial longitudinal directions. A projecting part 105b of the oscillation member 105 is oscillated or moved similarly to the oscillating member 105, and a free moving member 93 to be brought in contact with the projecting part 105 is upward moved. The upper end of the free moving member 93 is brought in contact with a limit switch 97, and a contact signal is output from the limit switch 97 to a transmitter. The signal is modulated into a radio signal, and the radio signal received by a receiving antenna through a transmitting antenna is output to a controller. The radio signal is demodulated into the contact signal, and an emergency stop command is output to an NC device.
ISHIZAKI YOICHI
IGARASHI TOSHIHIRO
KUMAMOTO SATOSHI
UCHIDA NOBORU
ITOU MASAYORI
TOSHIBA MACHINE CO LTD