Patent ID: 8910537

Claim:
A medical tool holding arm apparatus, comprising: a base unit set on a floor; a support unit uprightly arranged on the base unit, the support unit comprising a stationary support that is rotatably fixed to the base unit and a movable support that is vertically slidable along the stationary support; a vertical arm unit having an intermediate part that is rotatably supported with a third rotary shaft that is fixed in position at an upper end of the movable support of the support unit, and configured to be able to turn about the third rotary shaft over 180 degrees; a horizontal arm unit having a base that is rotatably supported with a first rotary shaft having a rotation center that is fixed in position at a first end of the vertical arm unit, a front end of the horizontal arm unit supporting a medical tool, and configured to be able to turn about the first rotary shaft over 180 degrees; a counterweight rotatably supported with a second rotary shaft having a rotation center that is fixed in position at a second end of the vertical arm unit; a clutch configured to put at least one of the first, second, and third rotary shafts into a freely rotatable state or a fixed state; and a torque transmission mechanism having a torque transmission member stretched between the first and second rotary shafts and configured to transmit torque of the counterweight about the second rotary shaft and torque of the horizontal arm unit about the first rotary shaft to each other.