Seiko Epson Corporation

Eisaku Shimizu

Kunio Koike

Hidenori Nakamura

Osamu Shinkawa

Osamu Takahashi

Akihiko Maruyama

Fumiaki Miyahara

Shigeyuki Fujimori

A radio-controlled timepiece has a reception means that receives a standard radio signal containing time information; a demodulation means that demodulates the standard radio signal received by the reception means and outputs a demodulated signal; a waveform discrimination means that discriminates the waveform of the demodulated signal based on a specific waveform discrimination standard, and outputs a code corresponding to the waveform; a time information conversion means that converts the code output by the waveform discrimination means to time information; and a waveform discrimination standard changing means for changing the waveform discrimination standard.

Radio-controlled timepiece and method of changing the waveform discrimination standard

A watch has a crown for manual time adjustment, a receiver for receiving current time update signals by radio transmission, an internal counter for counting the passage of time according to an internal oscillator, and time display hands. The watch preferably does not have a means for determining the position of its time display hands and therefore relies on user intervention for roughly correlating its time display hands to its internal counter. Preferably, the user begins a manual time correction operation when the second hand is at a predetermined position between 0-60 seconds. When the crown is pushed in, the seconds count value of the internal counter is reset to the predetermined position, and the watch waits for reception of a current time radio signal. When a radio signal is successfully received, the received seconds value is compared to the seconds count in the internal counter. If the time difference is within +30 seconds, the internal time is deemed to be advanced by the difference, and if the time difference is within &#x2212;30 seconds, the internal time is deemed to be delayed by the difference. The received time data is written into the internal counter, and the time display hands are moved according to the deemed time difference.

Radio-controlled timepiece and control method for the same

A radio-controlled timepiece reduces unnecessary power consumption and improves energy conservation. The radio-controlled timepiece has a reception unit power supply controllerthat regularly operates a reception power supply circuitthat drives a reception circuitfor receiving a radio signal containing time information. The reception unit power supply controllerhas an elapsed time detectorfor determining or measuring the elapsed time from the last time a signal was received, a reception schedule storagefor storing schedule information for supplying power, a schedule information setting-unitfor changing the schedule information to schedule information B with a longer power supply time interval than a default setting A if the elapsed time becomes greater than or equal to a set time, and a power supply circuit controllerthat controls operation of the reception power supply circuitbased on the schedule information. Because the frequency of signal reception is reduced if the period in which signal reception is not possible increases, power consumption can be reduced.

Radio-controlled timepiece and control method for a radio-controlled timepiece

An electronically controlled timepiece includes an analog circuit () driven by a power source (), a logic circuit () driven by a constant voltage regulator circuit () forming part of the analog circuit, an oscillator circuit () driven by the constant voltage regulator, a power source switch () for cutting off the supply of power to the analog circuit other than the constant voltage regulator circuit from the power source during a time correction operation, and a clock cutoff gate () for cutting off a clock input from the oscillator circuit to the logic circuit. During the time correction operation, power consumption is reduced because only the oscillator circuit and the constant voltage regulator circuit are operative. The oscillator circuit is not suspended, and an error in time display is eliminated.

Electronically controlled timepiece, and power supply control method and time correction method therefore

An electronically controlled mechanical timepiece, which is an electronic apparatus, includes a generator driven by a mainspring to generate electrical energy, and a rotation controlling unit driven by the electrical energy to control the rotation rate of the generator. The rotation controlling unit includes a brake controlling unit that compares a rotation detection signal indicative of the rotation rate of the generator with a reference signal to control braking on the generator, and a generator halting unit that applies a brake and halts the generator if the braking amount applied to the generator in a predetermined time is smaller than, or equal to, a first predetermined braking value. Because the generator is halted if a predetermined amount of cumulative brake applications are applied within the predetermined time, the generator is not halted in response to temporary disturbances while it is assuredly halted when the rotation becomes slow.

Electronic apparatus, electronically controlled mechanical timepiece, methods of controlling them, program for controlling electronic apparatus, and storage medium

To provide an electronic unit which can prevent brake control from stopping a generator. An electronically controlled mechanical timepiece, which is an electronic unit, includes a generator driven by a coil spring to generate electric power, and a rotation control unit driven by electric energy of the generator to control the rotation period of the generator . The rotation control unit is provided with a brake control unit for comparing a reference signal fs with a rotation-detection signal FG corresponding to the rotation period of the generator to apply brake control to the generator , and a generator-stop preventing unit for setting the amount of brake to be applied to the generator to a first brake setting value to prevent the generator from being stopped, when the rotation period of the generator is equal to or longer than a first setting period which is longer than a reference period. When the rotation period of the generator becomes long, the generator is controlled by the first brake setting value. The first brake setting value is a small amount of braking, such as zero, and can prevent the generator from being stopped.

Braking without stopping generator for timepiece and other electronic units

An electronically controlled mechanical timepiece, which is an electronic device, is equipped with a generator for converting the mechanical energy transmitted from a mainspring through the intermediary of a wheel train into electrical energy, and a rotation control unit for controlling the rotation cycle of the generator The rotation control unit is equipped with a count-up/down counter that compares a reference signal with a rotation detection signal of the generator thereby to adjust a braking time for the generator and a brake control signal generating circuit that corrects the time set at the count-up/down counter on the basis of the rotation cycle of the generator If the rotation cycle of the generator significantly deviates from a reference signal cycle, then the braking time is adjusted on the basis of the rotation cycle. Therefore, optimum brake control can be conducted, a secure and sufficient brake amount can be provided, and the responsiveness in speed control can be enhanced.

Electronic device, electronically controlled mechanical timepiece, and control method therefor

An electronically controlled timepiece includes an analog circuit ( ) driven by a power source ( ), a logic circuit ( ) driven by a constant voltage regulator circuit ( ) forming part of the analog circuit, an oscillator circuit ( ) driven by the constant voltage regulator, a power source switch ( ) for cutting off the supply of power to the analog circuit other than the constant voltage regulator circuit from the power source during a time correction operation, and a clock cutoff gate ( ) for cutting off a clock input from the oscillator circuit to the logic circuit. During the time correction operation, power consumption is reduced because only the oscillator circuit and the constant voltage regulator circuit are operative. The oscillator circuit is not suspended, and an error in time display is eliminated.

Electronically controlled timepiece, and power supply control method and time correction method therefor

An electronic device in which a braking torque can be increased while reduction in power generation is suppressed, and in which a rotor is prevented from stopping or rotating at an excessive speed. Such an electronic device includes a generator which is driven by an mechanical energy source and a rotation controller which controls the rotational period of the generator. The rotation controller includes two switches which connect both terminals of the generator in the form of a closed loop, a chopping signal generator which generates a chopping signal that is applied to the switches, and a brake control circuit which performs chopper control of the generator by selectively switching between three brake control modes including a high-power brake control mode in which the effective braking force generated by applying the chopping signal is relatively large a low-power brake control mode in which the effective braking force is relatively small, and a mid-power brake control mode in which the effective braking force is between that of the high- and low-power brake control modes.

Electronic device, electronically-controlled mechanical timepiece, and electronic device controlling method

A pointer electronic timepiece ( ) has a plurality of step motors, a plurality of pointers ( to ), and a plurality of external operation members of a winding crown ( ) and buttons ( ). The pointer to be adjusted is selected from the plurality of pointers ( to ) by operating one of the buttons ( ) while drawing out the winding crown ( ) to a second stage and the other button ( ) is operated to adjust the position of the selected pointer. Since the position of the pointers ( to ) driven by three step motors can be adjusted by the two buttons ( ), the number of the external operation member is not necessary to be increased even when the pointers ( to ), i.e. the step motors, are increased, so that the size and thickness of a movement-holder and cost thereof can be reduced and operability during adjustment can be improved.

Pointer electronic timepiece, operating method and control program thereof

With respect to a generator ( ), a storage device ( ) for storing electrical energy output from the generator and a bypass circuit ( ) are connected in parallel with each other. A bypass circuit switch ( ) of this bypass circuit ( ) is controlled on and off according to the voltage of the storage device ( ). This makes it possible to reduce the input current into the storage device so as to implement a reduction in the voltage of the storage device, thereby preventing overcharging. Moreover, since a generated waveform corresponding to the rotation period of the generator can be obtained, the rotation period of the generator can be controlled highly precisely and reliably based on this generated waveform, thereby implementing the indication of the correct time.

Electronically controlled mechanical watch and method of preventing overcharge

An electronic device capable of increasing the braking torque applied to an electric power generator without causing a significant reduction in electric power generated by the electric power generator. The electronic device, which may be embodied in an electronically controlled mechanical clock, includes an electric power generator for converting mechanical energy transmitted from a spring via a wheel train to electrical energy, and a rotation controller for controlling the rotation period of the electric power generator. The rotation controller includes switches capable of connecting two terminals of the electric power generator in a closed-loop state, a chopping signal generator for generating two or more types of chopping signals which are different in duty ratio or frequency for use in a strong braking operation, and chopping signal selector that selects one of the chopping signals, wherein, in the strong braking operation, the selected chopping signal is applied to the switches so as to control the electric power generator in a chopping fashion. The strong braking operation is performed in one of two modes such that a higher priority is given to generation of electric power or the braking torque depending on the mode, thereby achieving an increase in the braking torque of the electric power generator without causing a significant reduction in the voltage generated by the electric power generator.

Electronic device with variable chopping signal and duty ratio selection for strong braking

An electronic apparatus includes a power generator ( ) as a power supply, a capacitor ( ) for accumulating generated power, a logic circuit ( ) driven by the power from the capacitor, and a power supply cut-off circuit ( ). When the power generator starts operating,the power supply cut-off circuit ( ) does not supply power to the logic circuit ( ) until a voltage of the capacitor ( ) reaches a preset voltage. When the voltage of the capacitor ( ) becomes equal to or greater than the preset voltage, power is supplied from the capacitor to the logic circuit. Accordingly, a leakage current when power generation starts is prevented, and most of the generated power is accumulated in the capacitor. The capacitor, can rapidly accumulate electricity, and the time until activation of an electronic circuit driven by the capacitor is reduced.

Electronic device, electronic timepiece and power control method

An electronically controlled mechanical timepiece has first and second switches ( ) placed between an input terminal ( ) of a capacitor ( ) and output terminals MG and MG of a generator ( ), a third switch ( ) placed between the output terminal MG and an input terminal ( ) of the capacitor ( ), and a brake control circuit ( ) enabled to control the switches independent of one another. Electric current is fed through the generator by opening the switch ( ) and closing the switches ( ). Thus, a rate measurement pulse is outputted therefrom. Consequently, rate measurement is easily achieved.

Electrically controlled mechanical timepiece and control method therefor

An electronically controlled mechanical timepiece includes a mechanical energy source; a generator for converting mechanical energy transmitted through a train wheel to electrical energy. A rotation controller coupled to the generator controls rotation of the generator and includes switch capable of short circuiting the generator by intermittently activating and deactivating the switch using chopper control.

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Okaya, Japan

Eisaku Shimizu