JP2004061423A - Two hand type battery-run clock - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To discriminate a battery state of shutoff without a display means. <P>SOLUTION: The two hand type battery-run clock is provided with a reversibly stepping motor 4, a clock driving circuit part 3 which supplies control output switching a driving direction of a minute hand 6 and hour hand 7 in a regular direction or reverse direction, and a reference voltage detecting part 9 which detects the voltage state of the battery 2, and outputs detecting signal. Based on the output from the reference voltage detecting part 9, the clock driving circuit part 3 drives the reversibly stepping motor 4 in the regular direction or the reverse direction with a prescribed timing so as to make swing motion of the minute hand 6 to represents an alarm of dead battery. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a two-hand type battery watch having a function of displaying a warning of a power supply battery shortage state.
[0002]
[Prior art]
A battery timepiece includes, for example, a clock circuit unit having an oscillation circuit, a frequency divider circuit, a drive circuit, and the like using quartz, a stepping motor that is intermittently driven to rotate by a drive pulse output from the clock circuit unit, It has a pointer driving mechanism and the like driven by the rotation output from the motor. In a battery watch, when a drive voltage is applied from a battery to a clock circuit unit, the output of an oscillation circuit is divided by a divider circuit and the divided output is counted in the drive circuit, and the drive pulse is stepped from the drive circuit. Output to the motor. The battery timepiece drives the second hand, minute hand and hour hand by driving the gear train of the pointer driving mechanism by rotating the stepping motor by a fixed angle every time a drive pulse is applied, thereby displaying the current time in an analog manner.
[0003]
In the case of a battery watch, when the battery capacity becomes insufficient, it becomes impossible to gradually maintain the state of application of the specified voltage to the watch circuit unit, and the accurate timekeeping is performed without the hand driving mechanism being driven at a regular speed. Missing or stopped. In a large battery timepiece, for example, the battery voltage state is detected from a relation curve between the battery discharge time and the battery voltage. A device having a notification structure for notifying has also been proposed.
[0004]
[Problems to be solved by the invention]
By the way, small and light timepieces such as wristwatches are also used with a small battery such as a button battery mounted as a power battery. In the case of such a small timepiece, there is a problem that not only the size is increased by providing the above-described display means, but also the design is greatly restricted by the provision of the LED, and it has been difficult to mount the timepiece.
[0005]
For this reason, a small battery timepiece is provided with a battery capacity detection circuit section, and when detecting a state below the reference voltage, outputs an indefinite drive pulse from the clock circuit section to the pointer driving mechanism, for example, always performs a stepping operation. It has also been proposed to notify the battery exhaustion by moving the second hand in steps every two seconds. Such a small battery timepiece is extremely effective because its basic structure does not change and no display means is required.
[0006]
On the other hand, for example, many women's wristwatches generally have a two-hand structure of a minute hand and an hour hand, which do not have a second hand that constantly moves in a stepping manner. Therefore, in the two-hand timepiece, the above-described three-hand timepiece battery exhaustion notification structure cannot be adopted, and effective measures cannot be taken.
[0007]
Accordingly, it is an object of the present invention to provide a two-hand type battery timepiece that does not require a display means and can identify a dead battery state.
[0008]
[Means for Solving the Problems]
A two-hand type battery timepiece according to the present invention that achieves the above-described object has a reversible stepping motor, and a rotating operation of driving a minute hand and an hour hand in a forward direction and a rotating operation of a reversible stepping motor in a reverse direction. And a reference voltage detection unit that detects a voltage state of the battery and outputs a detection signal to the clock drive circuit unit.
[0009]
In the two-hand type battery timepiece, when the reference voltage detection unit detects a state where the output voltage of the battery is equal to or lower than the reference voltage, a detection signal is output from the reference voltage detection unit to the clock drive circuit unit. In the two-hand type battery timepiece, a control signal for driving the minute hand and the hour hand in the forward direction and a control signal for driving the hand in the reverse direction are output from the timepiece drive circuit unit to the reversible stepping motor. In a two-hand type battery timepiece, the minute hand that moves forward only in the normal direction in the normal state also moves stepwise in the reverse direction due to the rotation output in the forward and reverse directions from the reversible stepping motor. , A warning display indicating that the battery has run out can be made.
[0010]
In the two-hand type battery timepiece, the swinging operation of the minute hand for giving a warning of running out of battery in the forward and reverse directions is performed between the current time and the plus one minute time. Therefore, according to the two-hand type battery timepiece, the present time or the advance state within one minute is displayed, so that the inconvenience due to the time delay does not occur. Further, in the two-hand type battery timepiece, the swinging operation in the forward and reverse directions of the minute hand for giving a warning of running out of the battery is performed at shorter intervals than the one-minute stepping operation in the normal state. Therefore, in the two-hand type battery timepiece, it is possible to more reliably confirm the state in which the warning display indicating that the battery has run out is performed without impairing the time display function.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The two-hand type battery timepiece 1 shown in the embodiment also has a basic configuration similar to that of the conventional two-hand type timepiece, and includes a battery 2 as a driving source, a timepiece driving circuit unit 3, a stepping motor 4, a pointer A drive mechanism 5 is provided, and the minute hand 6 and the hour hand 7 perform a walking hand operation to display the current time by the relative position of the dial 8. As the battery 2, a small and thin so-called button type battery is used, and the back cover of a watch case (not shown) is opened and closed to be loaded inside.
[0012]
The battery 2 may be a rechargeable secondary battery or a solar battery. When such a rechargeable battery is used, the two-hand type battery watch 1 is provided with a charging circuit, a charging terminal, and the like. Although not described in detail, the two-hand battery timepiece 1 includes a power supply circuit, extracts a voltage from the loaded battery 2 and applies the voltage to the timepiece circuit unit 3. In addition, as for the battery 2, a relatively inexpensive primary battery is used in a general female wristwatch having many two-handed battery watches.
[0013]
Although not described in detail, the timepiece drive circuit unit 3 includes an oscillation circuit using quartz, a frequency divider circuit, a drive circuit, and the like. In the clock drive circuit section 3, quartz oscillates in response to a drive voltage applied from the battery 2, and a predetermined frequency signal is oscillated from the oscillation circuit and supplied to the frequency dividing circuit. The clock drive circuit section 3 divides the frequency signal in the frequency divider circuit, counts the frequency divided output in the drive circuit, and outputs a drive pulse from the drive circuit to the stepping motor 4.
[0014]
The stepping motor 4 is a so-called reversible stepping motor capable of performing a rotating operation for intermittently driving the minute hand 6 and the hour hand 7 in the forward direction and a rotating operation for intermittently driving the minute hand 6 and the hour hand 7 in the reverse direction. A reversible stepping motor that performs such an operation is disclosed in, for example, Japanese Patent Application Laid-Open No. Hei 2-2382, and includes a first magnetic field and a second magnetic field having a 90 ° angle difference with a rotatingly supported permanent magnet. It has a first coil and a second coil which are respectively generated.
[0015]
In the two-hand type battery timepiece 1, the clockwise driving pulse is applied to the reversible stepping motor 4 from the clock driving circuit unit 3 and the permanent magnet rotates forward at a predetermined angle. From 4, an intermittent rotation output of a predetermined angle is given to the pointer driving mechanism 5. In the two-hand type battery timepiece 1, when the output voltage of the battery 2 becomes equal to or lower than the reference voltage as described later in detail, the timepiece drive circuit unit 3 sends a forward rotation pulse to the reversible stepping motor 4 together with a forward drive pulse. A drive pulse in the reverse direction is applied. Therefore, the reversible stepping motor 4 provides the pointer driving mechanism 5 with the forward rotation output and the reverse rotation output at a predetermined angle.
[0016]
The pointer driving mechanism 5 includes, for example, a plurality of reduction gear trains that receive rotation transmission from an output gear provided on a rotation shaft of the stepping motor 4. The pointer driving mechanism 5 has a minute hand 6 attached to a gear at a predetermined stage, and an hour hand 7 attached to a gear at the last stage. The pointer driving mechanism 5 reduces the intermittent rotation output of the stepping motor 4 to a predetermined speed by a reduction gear train, and causes the minute hand 6 and the hour hand 7 to perform a stepping operation.
[0017]
The two-hand type battery timepiece 1 is provided with a reference voltage detector 9 for detecting the output voltage of the battery 2. The reference voltage detection unit 9 detects the output voltage V from the battery 2 and operates the clock drive circuit unit 3 in a state where the output voltage V is equal to or higher than the reference voltage V0 sufficient to drive the clock drive circuit unit 3. Keep in steady state. When detecting the state where the output voltage V from the battery 2 is equal to or lower than the reference voltage V0, the reference voltage detection section 9 outputs a detection signal to the timepiece drive circuit section 3.
[0018]
The reference voltage detector 9 is interposed, for example, between the power supply circuit and the timepiece drive circuit 3, and performs switching when the output voltage V from the battery 2 is higher than the reference voltage V0 and lower than the reference voltage V0. It consists of a voltage protection diode and the like. The reference voltage detector 9 not only directly detects the output voltage V from the battery 2 and outputs a detection signal, but also calculates the voltage state of the battery 2 from, for example, a relation curve between the discharge time of the battery 2 and the battery voltage. Alternatively, the detection signal may be output.
[0019]
In the two-hand type battery timepiece 1, when a detection signal is output from the reference voltage detecting unit 9 to the timepiece driving circuit unit 3, the minute hand 6 performs a characteristic stepping operation and the capacity of the battery 2 is in an insufficient state. A so-called low battery warning is displayed. In the two-hand battery timepiece 1, a forward drive pulse is applied to the reversible stepping motor 4 from the timepiece drive circuit unit 3 based on a detection signal from the reference voltage detection unit 9. In the two-hand type battery timepiece 1, this causes the reversible stepping motor 4 to rotate in the forward direction, and the minute hand 6 moves by one minute from the hands position at the current time via the hands driving mechanism 5. Do.
[0020]
In the two-hand type battery timepiece 1, based on the detection signal from the reference voltage detection unit 9, a drive pulse in the reverse direction is applied to the reversible stepping motor 4 at a predetermined timing from the timepiece drive circuit unit 3. . In the two-hand type battery timepiece 1, the reversing stepping motor 4 is rotated in the reverse direction by this operation, and the minute hand 6 is returned from the hand position of plus one minute to the current time via the hand drive mechanism 5. Perform the operation. In the two-hand type battery timepiece 1, the returning operation of the minute hand 6 is performed at a timing shorter than one minute, for example, about 10 seconds to 20 seconds.
[0021]
Further, in the two-hand battery timepiece 1, the minute hand 6 is re-driven at the same timing, and performs a step-up operation of one minute from the pointer position at the current time. In the two-hand type battery timepiece 1, when the same return operation of the minute hand 6 to the current time is performed in the following, the minute hand 6 swings and moves forward, and a warning of battery exhaustion is displayed to the user. In the two-hand type battery timepiece 1, the timekeeping operation of the timepiece drive circuit unit 3 is continued even during the warning display of running out of battery by the minute hand 6 described above, and the minute hand 6 and the hour hand 7 are stepped. .
[0022]
【The invention's effect】
As described in detail above, according to the two-hand battery timepiece according to the present invention, the reversible stepping motor is rotated in the forward direction at a predetermined timing by the timepiece drive circuit unit based on the detection signal output from the reference voltage detection unit. Since the minute hand is driven to swing in the reverse direction, the warning indicating that the battery is dead can be displayed to the user without providing a special display.
[Brief description of the drawings]
FIG. 1 is a main part configuration diagram of a two-hand type battery timepiece shown as an embodiment of the present invention.
[Explanation of symbols]
REFERENCE SIGNS LIST 1 two-hand type battery watch 2 battery 3 clock drive circuit unit 4 reversible stepping motor 5 pointer drive mechanism 6 minute hand 7 hour hand 8 dial 9 reference voltage detector

Claims (3)

In a two-hand type battery timepiece that displays the time by driving the minute hand and the hour hand step-by-step through a pointer driving mechanism by the rotation output of a motor powered by a battery,
Reversible stepping motor,
For the reversible stepping motor, a clock drive circuit unit that supplies a control output that switches between a rotating operation for driving the minute hand and the hour hand in a forward direction and a rotating operation for driving in a reverse direction,
A reference voltage detection unit that detects a voltage state of the battery and outputs a detection signal to the timepiece drive circuit unit,
When the battery voltage becomes lower than the reference voltage, the reversible stepping motor is repeatedly rotated in a forward direction and a reverse direction at predetermined intervals by the detection signal output from the reference voltage detection unit via the clock drive circuit unit. The two-hand type battery timepiece is characterized in that the minute hand swings to perform a warning display of running out of battery. 2. The two-hand type battery watch according to claim 1, wherein the swing operation of the minute hand for performing a warning display of battery exhaustion is performed between a current time and a plus one minute time. 3. The two-hand type battery according to claim 1 or 2, wherein the minute hand that performs the warning display of the battery exhaustion swings at an interval shorter than a step operation at an interval of one minute in a normal state. clock.

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