| 摘要 |
<p>PROBLEM TO BE SOLVED: To inexpensively realize such a structure that a sensor unit 35 can be easily attached to and detached from a cover 17a. SOLUTION: In a part of the cover 17a, an inserting hole into which the cylindrical section 36 of the sensor unit 35 can be inserted freely and a rotation inhibiting through hole 33 which can be matched to a sensor-side through hole 39 provided in the sensor unit 35 are formed. Engaging projections 34 and 34 are formed at two locations on the peripheral edge of the inserting hole 32. The projections 34 and 34 are engaged with and disengaged from thread parts 42 and 42 provided on the Outer peripheral surface of the cylindrical section 36 when the section 36 is rotated in the hole 32. The rotation of the sensor unit 35 against the cover 17a is inhibited by respectively inserting first and second locking pins 44 and 45 into the sensor-side through hole 39 and rotation inhibiting through hole 33.</p> |
