JPS6212300Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electronic timepiece having a step motor that is controlled to perform hand movement different from normal hand movement when an abnormality occurs in the timepiece.

The step motor of an electronic watch is designed with shock resistance, low temperature resistance, magnetic field resistance, etc. in mind, but if these are severe, the rotor of the step motor will not be able to rotate and the hands will stop moving. Put it away.

Once these influences are removed, the hands will resume movement. Also, if there is dust in the wheel train, the rotor will not be able to rotate, and if the dust is removed for some reason, the hands will resume movement. This phenomenon is generally referred to as a short stop, but if the second hand is moving normally when the user reads the time, the user may not notice that the second hand has stopped at a previous point, and may read the wrong time. It reads as accurate time.

The purpose of this invention is to eliminate the above-mentioned drawbacks, and once the watch stops moving, the hands move in a different way from the normal hand movement, so that the user is aware that there is an abnormality in the watch, and the time when the error has occurred. To obtain an electronic timepiece that does not read the time incorrectly as accurate time, and to provide an electronic timepiece that automatically returns to normal hand movement after an external operation such as a time adjustment operation is performed. The electronic timepiece according to the present invention uses a detection circuit that detects rotation or non-rotation of the rotor of the step motor. Once the above-mentioned stoppage is detected, the electronic timepiece performs a hand movement different from the normal hand movement, and can be restarted by operating an external operating member. It is characterized by a return to normal hand movement.

The present invention will be described below with reference to the drawings. FIG. 1 is a circuit block diagram of an electronic timepiece showing an embodiment of the present invention, and FIG. 2 is an output waveform diagram thereof.

In FIG. 1, 1 is a crystal oscillation circuit, and 2 is a frequency dividing circuit. 3 is a normal drive signal generation circuit which combines appropriate output stage signals of the frequency divider circuit 2 with various gates.
A normal drive signal as shown in waveform a in FIG. 2 is generated every second. 4 is a warning drive signal generation circuit which combines appropriate output stage signals of the frequency divider circuit 2 using various gates and generates two consecutive warning drive signals every 2 seconds as shown in waveform b in FIG. There is.

Reference numeral 5 denotes an electromagnetic coil opening/closing signal generating circuit which generates three consecutive pulse signals as shown in waveform c in FIG. 2 every second. 6 is a selection circuit, which is composed of AND gates 7 and 8 and an OR gate 9;
It is controlled by an output signal from a control circuit 27, which will be described later, and passes either a normal drive signal or a warning drive signal.

10 is a signal distribution circuit provided as a motor drive control means, which includes a toggle flip-flop 11 (hereinafter referred to as T-FF), AND gates 12, 13, 1
4, 15, inverters 16, 17, NOR gates 18, 19, etc., T-FF1
The input end of T-FF11 is connected to the output end of OR gate 9 of selection circuit 6, the output end Q of T-FF11 is connected to one end of AND gates 12 and 14, and the inverted output end of T-FF11 is connected to one end of AND gate 13, 15, and the other ends of the AND gates 12 and 13 are connected to the output terminal of the RO gate 9 of the selection circuit 6.
The other ends of the gates 14 and 15 are connected to the output end of the electromagnetic coil switching signal generating circuit 5.

Also, the output terminal of the AND gate 12 is connected to the inverter 16.
and one end of the NOR gate 18, the output end of the AND gate 13 is connected to the inverter 17 and one end of the NOR gate 19, the output end of the AND gate 14 is connected to the other end of the NOR gate 18,
The output end of the AND gate 15 is connected to the other end of the NOR gate 19. 20 is a drive circuit with four
Consists of MOS transistors, each
The output terminals of the inverters 16 and 17 and the NOR gates 18 and 19 described above are connected to the gates of the MOS transistors as appropriate. Reference numeral 21 denotes an electromagnetic coil, both ends of which are connected to the output ends of the drive circuit 20, respectively. A rotor 22 rotates one step each time a current flows through the electromagnetic coil 21 in the direction of the solid line arrow and the dotted line arrow. 23 is a detection circuit that detects rotation or non-rotation of the rotor 22 by the induced voltage generated in the electromagnetic coil 21, and is connected to inverters 24, 25 and NAND.
The input end of the inverter 24 is connected to one end of the electromagnetic coil 21, the input end of the inverter 25 is connected to the other end of the electromagnetic coil 21, and the output ends of the inverters 24 and 25 are connected to a NAND gate. 26 input terminals.
Regarding the input terminals of the inverters 24 and 25, as in the connection circuit according to another embodiment shown in FIG.
Connected to one end of the electromagnetic coil 21 through resistors 40 and 41 of about 200KΩ, and 800KΩ.
It may also be connected to the negative side of the power source via resistors 42 and 43 of approximately 100 Ω.

27 is a control circuit, a binary counter 28, AND
Gate 29, reset flip-flop 3
0 (hereinafter referred to as S-RFF), OR gate 31, 3
2, the input terminal of the counter 28 is normally connected to the output terminal of the drive signal generation circuit 3,
Each output terminal of the counter 28 is connected to a set terminal of the S-RFF 30 via an AND gate 29. The reset terminal of counter 32 is OR
Connected to the output terminal of gate 31, OR gate 31
One input terminal of is connected to the output terminal of the NAND gate 26 of the detection circuit 23 via an AND gate 33 whose one end is connected to the output terminal of the electromagnetic coil switching signal generation circuit 5, and the other input terminal is connected to the output terminal of the NAND gate 26 of the detection circuit 23. It is connected to the output terminal of the reset circuit 34, and the other input terminal is connected to the switch 35.

The power-on reset circuit 34 is configured to generate one pulse signal only when the battery 36 is turned on, and the switch 35 is normally connected to the negative side of the battery 36 and does not operate the external operating member 37. By operating it, it is connected to the positive side of the battery 36. The reset terminal of S-RFF30 is
Connected to the output terminal of OR gate 32,
The input terminal of the switch 2 is connected to the output terminal of the power-on reset circuit 34 and the switch 35.

The output terminal Q of the S-RFF 30 is connected to the AND gate 7 of the selection circuit 6 via an inverter 38, and also to the AND gate 8.

In the above configuration, when the battery 36 is first inserted, one pulse signal is generated from the power-on reset circuit 34, so the counter 28 and S-RFF
30 is reset, and the output signal of S-RFF 30 is held at the L signal. At this time, the switch 35 is connected to the negative side of the battery 36 since it is in a normal use state. Therefore, a normal drive signal as shown in waveform a in FIG. 2 passes from the selection circuit 6.
The signal is inverted and applied to the drive circuit 20 via the signal distribution circuit 10. Therefore, current flows through the electromagnetic coil 21 in the direction of the solid line arrow or the dotted line arrow direction, and the rotor 22 rotates by one step. When a predetermined time width has elapsed from the end of application of the normal drive signal, the waveform c in Fig. 2
As shown in the figure, the electromagnetic coil opening/closing signal is sent to the signal distribution circuit 1.
It is inverted and applied to the drive circuit 20 via 0.
Then, the electromagnetic coil 21 is switched from a closed loop state to an open loop state via the ON resistance of the MOS transistor of the drive circuit 20. At this time, an induced voltage is generated at one end of the electromagnetic coil 21 due to the free vibration of the rotor 22, and is applied to the inverter 24 or 25. This induced voltage exceeds the threshold voltage of the inverter 24 or 25 when the rotor 22 rotates normally, and cannot exceed the threshold voltage of the inverter 24 or 25 when the rotor 22 cannot rotate normally. . This technique is described in Japanese Unexamined Patent Publication No. 53-21966, and the explanation will be omitted here as it would be complicated.

Therefore, when the rotor 22 rotates normally, the NAND gate 26 of the detection circuit 23 outputs an H signal, and when the rotor 22 does not rotate, the NAND gate 26 outputs an L signal. In this explanation, the rotor 22 rotates normally, so the NAND gate 2
6 outputs an H signal, which is applied to the reset terminal of the counter 28 via the OR gate 31. The counter 28 outputs H and L signals according to the normal drive signal described above, but it outputs L and L signals according to the reset signal, and the S-RFF3
The output of 0 is held as an L signal. Thereafter, if there is no abnormality with the watch, the same operation as described above is repeated every second, and normal hand movement is performed every second.

Next, assuming that the rotor 22 is unable to rotate for some reason, when an inverted signal of the signal shown in waveform c in FIG. 2 is applied to the drive circuit 20,
An inverter 24 or 2 is connected to one end of the electromagnetic coil 21.
No induced voltage exceeding the threshold voltage of 5 is generated. Therefore, the signal from the NAND gate 26 becomes an L signal, the counter 28 is not reset, and the counter 32 continues to output H and L signals. However, the output of the S-RFF 30 remains the L signal.

Furthermore, the next normal drive signal is applied to the drive circuit 20, but since the rotor 22 could not rotate in the previous step, the phase of the next normal drive signal and the phase of the rotor 22 are opposite, and the rotor 22 Can't rotate. Therefore, the counter 28 is not reset again this time, and the output of the counter 28 becomes L and H signals. However, the output of S-RFF 30 remains at the L signal.

Furthermore, when the next normal drive signal is generated, the output of the counter 28 becomes an H, H signal, and the S-RFF
30 is set, and the output of the S-RFF 30 is switched and held at the H signal. Therefore, from the next step onward, what passes through the selection circuit 6 is a warning drive signal as shown in waveform b in FIG. Therefore, when the abnormal condition to the clock is removed afterwards, the rotor 2
2 is driven by the warning drive signal, and the hands move in 2-second steps, which is different from the normal hand movement.

Therefore, the user can notice that something is wrong with the watch by the movement of the second hand, and will not mistake an incorrect time display as an accurate time display. Next, the user operates the external operating member 37 in the direction of the solid arrow to set the time to the correct time. At this time switch 3
5 is connected to the positive side of the battery 36 as shown by the dotted line, so the counter 28 and S-RFF 30 are reset. At this time, the frequency dividing circuit 2 is also reset and the movement of the hands is stopped.

Next, for example, when the external operating member 37 is pushed in the direction of the dotted arrow in accordance with the time signal, the counter 28, S-
The reset of RFF 30 and frequency divider circuit 2 is released.

At this time, since the output of the S-RFF 30 is an L signal, the rotor 22 is driven by the normal drive signal, and the second hand returns to the normal movement state in which the second hand moves every second.

As is clear from the above explanation, in the electronic watch according to the present invention, when it detects non-rotation of the rotor of the step motor of the watch, the hands operate in a manner different from the normal hour movement. Returning to normal hand movement is a simple operation, and has great effects.

[Brief explanation of the drawing]

Fig. 1 is a circuit block diagram of an electronic timepiece according to an embodiment of the present invention, Fig. 2 is an output waveform diagram of the main part of the circuit block diagram shown in Fig. 1, and Fig. 3 is a drive circuit in the present invention. FIG. 3 is a connection circuit diagram showing another embodiment of the connection means of the detection circuit and the detection circuit. 3... Normal drive signal generation circuit, 4... Warning drive signal generation circuit, 6... Selection circuit, 23... Detection circuit, 27... Control circuit, 37... External operation member.

Claims (1)

[Scope of utility model registration request] In an electronic timepiece having a step motor, a normal drive signal generation circuit generates a normal drive signal, a warning drive signal generation circuit generates a warning drive signal different from the normal drive signal, and a combination of the normal drive signal and the warning. a selection circuit that selects and passes a drive signal; a drive circuit that inputs a signal from the selection circuit to drive the step motor; and a drive circuit that controls whether the rotor of the step motor rotates or not when driven by the normal drive signal a detection circuit for detecting rotation, an external operating member, and the detection circuit constantly passes the warning drive signal once the rotor detects non-rotation, and changes it to the warning drive signal by operating the external operating member. and a control circuit that controls the selection circuit to selectively pass the normal drive signal.