| 摘要 |
PROBLEM TO BE SOLVED: To prevent an optical unit from jumping out from an input pen even though it is engaged with a printed board and swung in the case of detaching a cap, by slidably engaging an annular projection to the inner part of a tail plug and an end part annular recessed groove loosely fitted at the tip part of the tail plug. SOLUTION: The optical unit 4 is fixed to the printed board 5 with an adhesive, and the end part of the printed board 5 is fixed to a board supporting member 6 and supported by it. The board supporting member 6 is moved to a rear part by the diameter reduction of the end part of the annular projection 8a of the tail plug 8 screwed to an outer cylinder 3 and the annular projection 8a of the tail plug 8 and the annular recessed groove 6b of the board supporting member 6 are slidably loosely fitted. In this case, at the time of turning a metal tip 2 and pulling out a tip cap 1 in the state of being detached from the outer cylinder 3 so as to remove dust and foreign matters clogged inside the tip hole 1a of the tip cap 1 of this input pen, even when the optical system unit 4 is also pulled with strong force, the pawl part 6a of the board supporting member 6 is hooked to the annular projection 8a of the tail plug 8 and it does not fall out. |
