STRUCTURE FOR PREVENTING ENCODER BUTTON FROM COMING OUT OF PLACE

摘要

Inner claws of a fitting part 210 of a dial 105 are engaged with engaging grooves in a rotary encoder 320. A plurality of retaining projections are formed in the dial 105. The retaining projections project radially outward from the fitting part 210 at circumferential intervals from one another. A through hole 500 through which the fitting part 210 can pass and a plurality of recesses through which the plurality of retaining projections can pass are formed in a door frame 120. The plurality of retaining projections are allowed to pass through the recesses only when the retaining projections are coincident in circumferential phase with the recesses. The retaining projections are positioned on one side of the recess portions opposite to an operation part 200 side so as to be freely turnable in synchronism with turning of the operation part 200.