Patent ID: 6520674
Filing Date: 2003-02-18
Classification: G01C,G04B,G04C,H01H

Abstract:
A mechanical timepiece comprising: a mainspring for generating a rotational force; a front train wheel for undergoing rotation in accordance with the rotational force generated by the mainspring; an escapement/speed-control device for controlling rotation of the front train wheel, the escapement/speed-control device having a balance with hairspring for undergoing reciprocal rotational movement, an escape wheel and pinion for undergoing rotation in accordance with rotation of the front train wheel, and a pallet fork for controlling rotation of the escape wheel and pinion in accordance with rotation of the balance with hairspring; a stitch mechanism for outputting an ON signal when a rotation angle of the balance with hairspring becomes a predetermined threshold angle or greater and for outputting an OFF signal when the rotation angle of the balance with hairspring does not exceed the predetermined threshold angle; a position-detecting device for detecting a position of the mechanical timepiece; and a balance-with-hairspring rotation angle control mechanism for applying a force to suppress rotation of the balance with hairspring when the switch mechanism outputs an ON signal in accordance with a position of the mechanical timepiece detected by the position-detecting device.