摘要 |
1,090,187. Clocks and watches. LABORATORNI PRISTROJE, NARODNI PODNIK. Dec. 21, 1964 [Jan. 6, 1964], No.51789/64. Heading G3T. [Also in Division F2] A mainspring 3 of a timepiece is intermittently wound by a continuously rotating electric motor 24. Motor 24 drives a gear 17 which is freely rotatable on a shaft 5 and has a sleeve portion 18. A flange 15 is fixed to the shaft 5 and has a sleeve portion 16. A helical spring clutch 20 surrounds the portions 16 and 18, one'end being fixed in the portion 16 and the other end 21 freely rotable until it abuts a stop 11. Rotation of the gear 17 causes the clutch 20 to tighten and rotate the shaft 5 to wind spring 3 until the end 21 abuts stop 11 to release the clutch. The mainspring rotates the clutch as it unwinds to reset the position of the portion 21. If the motor 24 fails the mainspring is allowed to rotate for four revolutions before being stopped by the stop 11 which is mounted on a maltese cross 9 rotated by a pin 13 on the flange 15. Each revolution of the mainspring rotates the stop 11 through 90 until it abuts the portion 21 from the opposite direction to lock the clutch to the stationary wheel 17. |