| 摘要 |
PROBLEM TO BE SOLVED: To perform constant-velocity rotary movement of a sewing cam on the button hole side, which is eccentrically fitted to a camshaft. SOLUTION: A plurality of projections 10c are projected extending in the axial direction on the face opposite to a button hole side sewing cam 12 of a centering cam group 10, and a plurality of holes 12a of the same number as that of the projections are formed in the face of the button hole side sewing cam 12 that is opposite to the centering cam group 10. The plurality of projections 10c and the plurality of holes 12a are respectively loosely fitted to each other. Thus, the engagement of the projections and the holes 1a for giving the driving force is gradually changed with the rotation of the centering cam group 10 and the button hole side sewing cam 12, and the position to which the force is applied is not changed, and the rotating speed of the button hole side sewing cam 12 is determined by receiving the rotating speed of the projection 10c at that position, whereby the button hole side sewing cam 12 is caused to perform constant-velocity circular motion. In this case, when the diameter of the hole 12a is taken as D, and the diameter of the projection 10c is taken as d, the hole 12a and the projection 10c are preferably designed to satisfy the formula: d+2R≤D. COPYRIGHT: (C)2003,JPO
|
