JPS647346B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electronic timepiece having two step motors: a step motor for driving the second hand and a step motor for driving the hour and minute hands.

In a typical three-hand electronic watch, a single step motor drives the second hand and hour/minute hands.
In such three-hand electronic watches, the so-called electromagnetic correction method, in which the indicated position of the hands is corrected by driving a step motor based on a correction signal, is not adopted because it takes too much time to correct. do not have. However, in order to realize an analog electronic watch that has additional functions in addition to the simple time display function, such as a time difference correction function watch, and an alarm function watch where the hour and minute hands for time display also serve as alarm guide hands, It is essential to adopt the electromagnetic correction method described above.

Recently, in order to realize an analog electronic timepiece having various functions, an electronic timepiece having two step motors, a step motor for driving the second hand and a step motor for driving the hour and minute hands, has been proposed. In this type of watch, the second hand and the hour and minute hands can be driven independently, so the indicated positions of the second hand or the hour and minute hands can be corrected in a short time by electromagnetic correction.

However, in this type of watch, since the two step motors are driven independently, there is a possibility that even if the hour and minute hands stop moving for some reason, only the second hand continues to move. In such a case, the user of the watch may think that the watch is operating normally, and there is a great risk that the user will read the incorrect time display as the correct time display.

The purpose of the present invention is to eliminate the above-mentioned drawbacks, and to provide an electronic timepiece that can cause the second hand to move in a manner different from the normal movement when an abnormality occurs in the watch, thereby notifying the user that there is an abnormality in the watch. The electronic timepiece according to the present invention includes a warning second hand driving signal generation circuit that generates a signal to cause the second hand to perform a hand movement different from the normal hand movement, and a rotor rotation and non-rotation circuit of a step motor for driving the hour and minute hands. a detection circuit for detecting rotation, a control circuit for controlling a signal generated when the detection circuit detects non-rotation of the rotor, and a signal for normal hand movement or modulated hand movement under the control of the signal from the control circuit. By passing the selection, if it is detected that the hour/minute hand motor is not rotating, the second hand, which is driven by the other motor, is moved in a modulated manner to issue a warning.

The present invention will be described in detail below with reference to the drawings.

FIG. 1 is a circuit block diagram showing an embodiment of an electronic timepiece according to the present invention, and FIG. 2 is a signal waveform diagram thereof. In FIG. 1, 1 is a crystal oscillation circuit, and 2 is a frequency dividing circuit. Reference numeral 3 denotes a signal generating circuit for driving the normal second hand, which generates a signal for driving the normal second hand every second as shown in waveform A in FIG. Reference numeral 4 denotes a warning second hand driving signal generation circuit which generates two consecutive warning second hand driving signals every two seconds as shown in waveform B in FIG. 5 is a signal generation circuit for driving the hour and minute hands, which generates a signal for driving the hour and minute hands every 20 seconds as shown in waveform C in FIG. 6 is an electromagnetic coil opening/closing signal generation circuit, which generates 3 signals every 20 seconds as shown in waveform D in Figure 2.
It generates two consecutive narrow-width electromagnetic coil opening/closing signals.

The output signals of the normal second hand driving signal generating circuit 3, the warning second hand driving signal generating circuit 4, the hour/minute hand driving signal generating circuit 5, and the electromagnetic coil opening/closing signal generating circuit 6 are sent to an appropriate output stage of the frequency dividing circuit 2. Normally, the second hand driving signal and the hour/minute hand driving signal are shifted in phase to reduce the load on the battery 44.

7 is a selection circuit, which is composed of AND gates 8 and 9 and an OR gate 10, and is connected to a control circuit 35 to be described later.
is controlled by the output signal of and selects and passes either the normal second hand driving signal or the warning second hand driving signal described above. 11 is a signal distribution circuit for driving the second hand, and a toggle flip-flop 12 (hereinafter referred to as T-
FF) and NAND gates 13 and 14, and the input terminal of the T-FF 12 is connected to the selection circuit 7.
It is connected to the output terminal of the OR gate 10, and the input terminal of the NAND gate 13 is connected to the output terminal of the OR gate 10 and T
- is connected to the output terminal Q of FF12, and the input terminal of NAND gate 14 is connected to the output terminal of OR gate 10 and T-
Connected to the output end of FF12.

15 is a drive circuit for driving the second hand, which consists of four MOS
Consists of transistors, input terminal is NAND
It is connected to the output ends of the gates 13 and 14, and an electromagnetic coil 16 of a step motor for driving the second hand is connected to the output end.

17 is a rotor for driving the second hand, and electromagnetic coil 1
6. Together with the stator (not shown), a step motor for driving the second hand is configured, and the motor rotates one step each time a current with a different direction flows through the electromagnetic coil 16, and drives the second hand through a gear train (not shown). Drive.

18 is a signal distribution circuit for driving the hour and minute hands, and T-
FF19, AND gate 20, 21, 22, 23,
Inverters 24, 25, NOR gates 26, 27
etc., and the input terminal of T-FF19 is
connected to the output terminal of the minute hand drive signal generation circuit 5;
The input terminals of AND gates 20 and 21 are
Output terminal of minute hand drive signal generation circuit 5 and T-FF
connected to the output terminal Q or of the AND gate 22,
The input terminal of 23 is connected to the output terminal Q of T-FF 19 and the output terminal of electromagnetic coil switching signal generation circuit 6.

Also, the input terminal of the inverter 24 is the AND gate 2
0, and the input terminal of the NOR gate 26 is connected to the output terminal of the AND gate 20 and the AND gate 2.
The input end of the inverter 25 is connected to the output end of the AND gate 21, and the input end of the NOR gate 27 is connected to the output ends of the AND gate 21 and the AND gate 23.
28 is a drive circuit for driving the hour and minute hands, and there are four
It is composed of MOS transistors, and the input terminals are inverters 24, 25, NOR gate 26,
27, and an electromagnetic coil 29 of a step motor for driving the hour and minute hands is connected to the output end.

30 is a rotor for driving the hour and minute hands, which together with an electromagnetic coil 29 and a stator (not shown) constitutes a step motor for driving the hour and minute hands, and rotates one step each time a current in a different direction flows through the electromagnetic coil 29. and drives the hour and minute hands via a gear train (not shown). 31 is a detection circuit for detecting rotation or non-rotation of the rotor 30, which is connected to inverters 32 and 33;
The output terminals of the inverters 32 and 33 are connected to the input terminal of the NAND gate 34, and the input terminals are connected to both ends of the electromagnetic coil 29.

35 is a control circuit, AND gates 36, 37,
OR gates 38, 39, binary counter 40, reset flip-flop 41 (hereinafter S-
RFF), AND gate 3
The input terminal of the OR gate 6 is connected to the output terminal of the NAND gate 34 and the output terminal of the electromagnetic coil switching signal generation circuit 6, and the input terminal of the OR gate 38 is connected to the output terminal of the AND gate 36, the switch 42, and the output of the power-on reset circuit 43. The input terminal of the OR gate 39 is connected to the switch 42 and the power-on reset circuit 4.
They are connected to the output terminals of 3. Note that the power-on reset circuit 43 is configured to generate one pulse signal only when the battery 44 is turned on, and the switch 42 is normally configured so that the external operating member 45 is pushed in the direction of the solid arrow, so that the power-on reset circuit 43 generates only one pulse signal when the battery 44 is turned on. Connected to the negative side.

Next, the input terminal of the counter 40 is connected to the output terminal of the hour/minute hand drive signal generation circuit 5, and the reset terminal is connected to the output terminal of the hour/minute hand drive signal generation circuit 5.
The input terminal of the AND gate 37 is connected to the two output terminals of the counter 40, the set terminal of the S-RFF 41 is connected to the output terminal of the AND gate 37, and the reset terminal is connected to the output terminal of the AND gate 37. It is connected to the output terminal of 39. Also, control circuit 3
The output terminal of the S-RFF 41, which is the output terminal of the inverter 4, is connected to the input terminal of the AND gate 8 of the selection circuit 7.
6 and directly connected to the input terminal of AND gate 9.

Next, the operation will be explained. When the battery 44 is first inserted, one pulse signal is generated from the power-on reset circuit 43, and the counter 40 and S-
RFF 41 is reset, counter 40 and S
-The output of RFF41 becomes an L signal. At this time, since the external operating member 45 is pushed in the direction of the solid arrow, the switch 42 is connected to the negative side of the battery 44. Therefore, selection circuit 7
A normal second hand drive signal as shown in FIG. 2A passes through the second hand drive signal distribution circuit 11, drive circuit 15, and electromagnetic coil 16 to drive and rotate the rotor 17 every second. Therefore, the second hand is driven via the wheel train and moves normally every second.

Also, from the hour/minute hand drive signal generation circuit 5, a second
Since the hour and minute hand drive signals shown in waveform C in the figure are generated every 20 seconds, the rotor 30 is driven every 20 seconds via the hour and minute hand drive signal distribution circuit 18, drive circuit 28, and electromagnetic coil 29. time and through the gear train.
The minute hand is driven and moves.

After a short period of time has elapsed after the application of the hour and minute hand drive signals is completed, an electromagnetic coil opening/closing signal as shown in waveform D in FIG. 2 is applied to the drive circuit 28. At this time, due to the rotational movement of the rotor 30, the electromagnetic coil 29
An induced voltage is generated at one end of the . When the rotor 30 rotates normally, this induced voltage is transferred to the inverter 32,
Or the threshold voltage of the inverter 32 or 33 is exceeded, and in the case of non-rotation that does not rotate normally, the threshold voltage of the inverter 32 or 33 is not exceeded.

This operating principle has already been described in Japanese Patent Application Laid-open No. 53-
21966, detailed explanation will be omitted here.

Next, a case where the rotor 30 rotates normally will be described. When the rotor 30 rotates normally, a voltage exceeding the threshold voltage is applied to one of the inverters 32 or 33, so an L signal is output from one of the inverters 32 or 33, and an H signal is output from the NAND gate 34. Output. Therefore, the counter 40 is
is reset, and the output of S-RFF 41 remains at the L signal. Therefore, the second hand is normally driven based on the second hand driving signal. In this way, time
When the rotor 30 for driving the minute hand rotates normally, the second hand moves normally.

Next, if the rotor 30 is unable to rotate normally due to some reason such as impact, dust, low temperature, magnetic field, etc., even if the electromagnetic coil opening/closing signal is applied to the drive circuit 28, one end of the electromagnetic coil 29 will not connect to the inverter 32. Otherwise, a voltage exceeding the threshold voltage of 33 is not generated, and the NAND gate 34 does not output an H signal. Therefore, the counter 40 is not reset, and the counter 40 is counted by the hour and minute hand drive signals and outputs "L" and "H" signals. However, at this time, S-RFF41 has not been reset yet.
The output of S-RFF41 holds the L signal and the next 20
During the seconds, the second hand moves normally every second. After 20 seconds have elapsed, the next hour/minute hand drive signal is applied to the drive circuit 28, but since the rotor 30 could not rotate normally last time, the phase with the next hour/minute hand drive signal does not match, and the next time It also cannot rotate properly.

Therefore, even if the electromagnetic coil opening/closing signal is applied to the drive circuit 28, a voltage exceeding the threshold voltage of the inverters 32 and 33 is not generated from one end of the electromagnetic coil 29, and the counter 40 is not reset.

Therefore, the counter 40 counts based on the hour and minute hand driving signals and outputs "H" and "L" signals.
However, even at this time, the output of the S-RFF 41 still maintains the L signal, and the second hand continues to move normally every second for the next 20 seconds. Next, when 20 seconds have elapsed, the counter 4 is activated by the hour and minute hand drive signals.
0 is counted and "H" and "H" signals are output. Therefore, the S-RFF 41 is set, and the output of the S-RFF 41 is switched and held at the H signal.

This state will not change even if the rotor 30 starts to rotate normally thereafter.

When the H signal is output from the S-RFF 41, a warning second hand drive signal as shown in waveform B in FIG. will begin to do this. If the rotor 30 fails to rotate normally twice in a row in this way, the second hand will continue to move every two seconds even if the rotor 30 subsequently starts rotating normally. As a result, the user of the watch notices that there is something wrong with the watch and knows that the time display is incorrect.

Next, the user uses the external operating member 4 to adjust the needle.
5 in the direction of the dotted arrow. For example, when the external operating member 45 is rotated, a correction signal is applied from a time correction signal generation circuit (not shown) to the drive circuit 28, and the rotor 30 is rotated to perform hand alignment. At this time, since the switch 42 is connected to the positive side of the battery 44, the counter 40 and S-
The RFF 41 is reset and the output of the S-RFF 41 is switched and held at the L signal. The frequency divider circuit 2 is also reset.

After setting the hands at the correct time, when the external operating member 45 is pushed in the direction of the solid arrow, the switch 42 is connected to the negative side of the battery 44 again.
The reset of the frequency divider circuit 2 is also released. Therefore, from the next step onwards, the second hand will move normally every second.

As is clear from the above explanation, in the electronic watch according to the present invention, if the hour and minute hands temporarily stop moving for some reason, the second hand moves differently from the normal hand movement, so the user may incorrectly display the time. This also prevents the display from being read as a correct time display.

It should be noted that the second hand may be configured to automatically move normally after the hand alignment operation is performed by operating the external operating member.

[Brief explanation of drawings]

FIG. 1 is a circuit block diagram of an electronic timepiece according to the present invention, and FIG. 2 is an output voltage waveform diagram of a main part of the circuit block diagram shown in FIG. 3... Signal generation circuit for normal second hand drive, 4... Signal generation circuit for warning second hand drive, 5... Signal generation circuit for hour/minute hand drive, 7... Selection circuit, 15... Drive circuit for second hand drive, 16... Electromagnetic coil of the step motor for driving the second hand, 17... Rotor of the step motor for driving the second hand, 28... Drive circuit for driving the hour and minute hands, 29... Electromagnetic coil of the step motor for driving the hour and minute hands, 30 . . . Rotor of the step motor for driving the hour and minute hands, 31 . . . Detection circuit, 35 . . . Control circuit.

Claims (1)

[Claims] 1 Normally, the second hand drive step motor is driven by a signal from the second drive signal generation circuit, and the hour and minute drive step motor is driven by signals from the hour and minute drive signal generation circuit.
In an electronic watch having a step motor for driving the minute hand, a warning second drive signal generating circuit generates a signal for causing the second hand to perform a modulated hand movement different from normal hand movement, and a rotor of the step motor for driving the hour and minute hands. a detection circuit that detects rotation or non-rotation of the rotor; a control circuit that is controlled by a signal from the detection circuit that is generated when non-rotation of the rotor is detected; and a control circuit that generates the normal second drive signal based on the signal from the control circuit. The circuit includes a selection circuit that selectively passes a signal from the circuit or the signal from the warning seconds drive signal generation circuit, and when it is detected that the hour/minute hand drive motor does not rotate, the second hand drive motor is activated. An electronic timepiece characterized in that the second hand is configured to move in a modulated manner by applying a modulation signal.