Patent ID: 7197835

Claim:
A detector supporting mechanism comprising: a first arm having its one end fixed on a mount linearly movable relative to a workpiece, the first arm having a rotation axis at the other end; and a second arm provided on the first arm so as to be turnable on the rotation axis relative to the first arm, a detector being mounted on a tip of the second arm, wherein the first arm comprises a first segment which extends in a radial direction with respect to the rotation axis thereof, and a second segment that has a mounting surface for the second arm that is bent through an angle of 45° in a longitudinal direction relative to an adjoining surface of said first segment about a vertical axis and is twisted through an angle of 45° from a vertical plane, wherein the second arm is mounted on the second segment of the first arm, wherein an axis of the detector mounted on the second arm intersects the rotation axis of the first arm, wherein the detector has a detection direction which is perpendicular to its axis, and wherein the detection direction of the detector is settable in a vertical direction, a horizontal direction or an intermediate direction between the vertical and horizontal directions by rotating the second arm around the rotation axis thereof and positioning the second arm at a predetermined position.