| 摘要 |
PROBLEM TO BE SOLVED: To provide a rotation device for a thumb turn that can have the thumb turn incorporated easily in a seat plate and engaged and disengaged at a plurality of positions, and gives an excellent feeling of operation on the thumb turn.SOLUTION: A seat plate 2 and a seat plate 3 are fitted to both surfaces of a door D, a thumb turn 1 is fitted to the seat plate 2 while a square core 13 is fitted on the side of the seat plate 3, and the square core 13 is inserted into a square hole 8 formed in the thumb turn 1. The thumb turn 1 includes a top-side knob part 4 and a reverse-side shaft part 5, a loose fitting groove 7 is formed in the shaft part 5 over the entire outer periphery and provided with engagement parts 6, 6 at two places which are 180 degrees displaced, and the square hole 8 is formed in the shaft part 5. The seat plate 2 is provided with a circular hole and has a cylindrical part projected at periphery on the reverse side of the circular hole, the cylindrical part has cuts 11, ..., 11 formed at four places while the remaining part serves as a bearing part 9. The bearing part 9 is provided, on its inner peripheral surface, with lock pieces 12, ..., 12 projecting inward at the tip and lock parts 10, 10 in a triangular groove shape provided at two opposite places. |
