PURPOSE: To provide a control apparatus for a core drill, which can automati cally set the optimum current value for every bit size without performing setting judgment and setting operation of the bit size.
CONSTITUTION: A core drill 1 comprises a rotation-driving transmitting part, which rotates a core bit, a feed mechanism, which determines the advancing and withdrawing positions, and a transmission part, which is engaged with the feed mechanism, includes a bit-feed motor 16 and makes the core bit advance and withdraw. A control apparatus 3 sets a current setting value 107 based on a bit-feed-speed detecting signal 100 and controls the operation of the motor 16 with the current setting value 107 and a deviation signal 104 of a motor current signal 105. The control apparatus 3 has a bit-size detecting and setting means 35, which determines the size of the core bit based on a motor current signal 120 and obtains an optimum bit-size-current setting value 106 for the obtained size. The current setting value based on the detected signal 100 is corrected with the current setting value 106, and the new current setting value is obtained.
KOTANI KAZUNORI
FURUMITSU SEISABURO
ISHII YOSHIKIYO
ABE TAKAO
GOEI SEISAKUSHO KK