| 摘要 |
683,485. Time-alarm signals. MANUFACTURE D'HORLOGERIE DE BETHUNE. Feb. 14, 1950 [Feb. 22, 1949], No. 3714/50. Class 118 (ii) [Also in Group XVIII] A time alarm for giving an audible alarm at the end of predetermined periods of time up to sixty minutes comprises a clock movement provided on the centre spindle with a cam adapted at the end of the set period to engage a projection provided at the end of one arm of a pivoted bell-crank lever which is thereby moved to free the alarm hammer. A cam 2, Fig. 1, on the centre spindle 1 of the clock movement has a projection 3 for moving a bell-crank lever 5, 6 against the pressure of a spring 9 to free the hammer carrying lever 17, 15 at the expiry of any period up to sixty minutes as set by moving a pointer, Fig. 2 (not shown), over a scale to the required time indication from which the pointer is driven back to zero. The bell-crank lever 5, 6 rocks clockwise to arrest the lever 17, 15 when disengaged by the projection 3. |
