Braking without stopping generator for timepiece and other electronic units

An electronically controlled mechanical timepiece comprising a mechanical energy source, a generator driven by the mechanical energy source to generate induction electric power to supply electrical energy, a rotation control unit driven by the electrical energy to control the rotation period of the generator, and a time indication unit operated with the rotation of the generator, the rotation control unit comprising:

• a brake control unit that compares a reference signal, generated according to a signal sent from a time reference source, with a rotation detection signal corresponding to the rotation period of the generator to apply brake control to the generator;
• and
• a generator-stop preventing unit that sets the amount of brake applied to the generator to a first brake setting value when a measured rotation period of the generator is equal to or longer than a first setting period, which is longer than a reference period, to prevent the generator from stopping.

A control program for an electronic unit comprising a mechanical energy source, a generator driven by the mechanical energy source to generate induction electric power to supply electrical energy, and a rotation control unit driven by the electrical energy to control the rotation period of the generator, the control program for the electronic unit controlling the rotation control unit to:

• compare a reference signal, generated according to a signal sent from a time reference source, with a rotation detection signal corresponding to the rotation period of the generator to apply brake control to the generator;
• and
• set the amount of brake applied to the generator to a first brake setting value when a measured rotation period of the generator is equal to or longer than a first setting period, which is longer than a reference period, to prevent the generator from stopping.

A recording medium recording a control program for an electronic unit comprising a mechanical energy source, a generator driven by the mechanical energy source to generate induction electric power to supply electrical energy, and a rotation control unit driven by the electrical energy to control the rotation period of the generator, the recorded control program for the electronic unit controlling the rotation control unit to:

• compare a reference signal, generated according to a signal sent from a time reference source, with a rotation detection signal corresponding to the rotation period of the generator to apply brake control to the generator;
• and
• set the amount of brake applied to the generator to a first brake setting value when a measured rotation period of the generator is equal to or longer than a first setting period, which is longer than a reference period, to prevent the generator from stopping.

A control method for an electronic unit comprising a mechanical energy source, a generator driven by the mechanical energy source to generate induction electric power to supply electrical energy, and a rotation control unit driven by the electrical energy to control the rotation period of the generator, the control method comprising:

• comparing a reference signal, generated according to a signal sent from a time reference source, with a rotation detection signal corresponding to the rotation period of the generator to apply brake control to the generator;
• and
• setting the amount of brake applied to the generator to a first brake setting value when a measured rotation period of the generator is equal to or longer than a first setting period, which is longer than a reference period, to prevent the generator from stopping.

An electronic unit comprising a mechanical energy source, a generator driven by the mechanical energy source to generate induction electric power to supply electrical energy, and a rotation control unit driven by the electrical energy to control the rotation period of the generator, the rotation control unit comprising:

• brake control means for comparing a reference signal, generated according to a signal sent from a time reference source, with a rotation detection signal corresponding to the rotation period of the generator to apply brake control to the generator;
• and
• generator-stop preventing means for setting the amount of brake applied to the generator to a first brake setting value when a measured rotation period of the generator is equal to or longer than a first setting period, which is longer than a reference period, to prevent the generator from stopping.