| 摘要 |
940,312. Clocks and watches. KIENZLE UHRENFABRIKEN A. G. Oct. 6, 1961 [Feb. 22, 1961], No. 35999/61. Heading G3T. In a watch balance regulator, in order that the curbing point A of the balance spring shall lie substantially in a central position between the curb pins or the like of the regulator arm throughout the range of angular adjustment of this arm, and to avoid any necessity for an additional radial adjustment, the balance spring retains its general shape of an Archimedean spiral of the form in polar co-ordinates r = S/2# # over the outer peripheral portion which is engaged by the curb pins, the arm being rotatable round a fixed axis M at the distance r from the point A, which axis in the zero position of the regulator lies on the normal to the spiral at the point A, this normal forming with the radius vector OA (O being the origin of the spiral) an angle α determinable from the expression tan α = S/2#r. The value of # being expression tan α = S/2#r. The value of # being normally about 21# at the point A, it is shown that for this value the length r is approximately equal to the radius of curvature of the spiral at this point, thence the circular concentric movement of the curb pins corresponds closely to the curvature of the spiral. |
