| 摘要 |
The invention contributes to improving the operation of a timepiece of the type with lever escapement and in particular the stability of the mechanism, and hence the beat frequency. The invention relates more precisely to the shape of the teeth of the wheel. Each of these possesses a front face 12 and a back face 13 which are defined by the direction of rotation of the wheel. The front face makes an acute angle with the root diameter 15 of the wheel so that the lifters 8 and 9 of the escapement lever 3 can penetrate virtually as far as the root of the tooth. These lifters bear against the tooth via a curved surface 11 tangential at the point A to the upper portion of the front face and which extends as far as the end of the tooth constituted by the ridge 14. This shape of tooth tends to eliminate shocks between the lifters and each of the teeth, and hence promotes uniformity of operation. A use is provided for within a timepiece of the type with lever escapement used in a flare mortar shell fuse. <IMAGE>
|
