STRUCTURE OF COUPLING SHAFT AND PLATE

PROBLEM TO BE SOLVED: To provide a coupling structure capable of coupling a shaft to a plate in a preferably positioned state while facilitating manufacture of the plate.SOLUTION: A control shaft has opposing faces comprising two flat planes which are parallel and opposing to each other, on a side face. A through-hole 24 is formed at the end portion 23 of a control lever 7. The through-hole 24 includes a second insertion hole portion 26 where the control shaft is to be inserted. The second insertion hole portion 26 includes two turn regulating faces 28 and two expanding faces 29 on a side face. Each turn regulating face 28 comprises a flat plane to be parallel to the axial line of the control shaft inserted into the second insertion hole portion 26. The two turn regulating faces 28 are parallel and opposed to each other at a distance substantially equal to the width between two opposing faces 14 of the control shaft. The second insertion hole portion 26 has an insertion regulating face 30 extending in a direction orthogonal to the turn-regulating faces 28.