JPS6113193B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an analog display electronic wristwatch with a motor.

Conventionally, analog display electronic wristwatches that use a step motor or the like as an electromechanical converter have had the problem that when placed in a strong external magnetic field, the watch will not rotate and will stop even if a signal is input to the motor. To this end, anti-magnetic plates were installed to reduce the influence of external magnetic fields, but this not only increased the number of motor parts and increased costs, which was an obstacle to miniaturization, but also reduced motor efficiency. It was also getting warmer.

The purpose of the present invention is not only to eliminate these drawbacks, but also to prevent the clock from becoming out of order even in the presence of any strong magnetic field.

The present invention will be explained below with reference to the drawings. Figure 1 shows
This is an example of the present invention. This is because when an external magnetic field above a certain level is applied, the time information is stored in a counter, which is a memory circuit that temporarily stores time information without inputting a 1-second signal to the motor, and when the external magnetic field is removed, the counter The contents are fast-forwarded and input into the motor, and the time when the clock has stopped is corrected. The signal from the oscillation circuit 1 is frequency-divided by the frequency divider circuit 2, the 1-second signal generation circuit 3 generates a normal clock hand movement signal, and the fast-forward signal generation circuit 4 generates a fast-forward pulse, and the overall time reference signal is It constitutes a generating means.

The output of the time reference signal generating means is connected to a first signal switching means consisting of AND gates G1 and G2.
The signal is input to a second signal switching means consisting of AND gates G4, G5, and G6. The output of the first signal switching means is input to a storage means comprising a counter 6, a counter 8, and a matching circuit 7 for storing time information, and is also input to a drive circuit 9. The external magnetic sensing circuit 5 is connected to the first and second signal switching means.
The second signal switching circuit is connected to a group of AND gates, and also receives the output of the matching circuit 7 of the storage means, and inputs the fast-forward pulse from the fast-forward signal generating circuit 4 of the reference signal generating means to the drive circuit 9. is under control.

Next, the operation of the present invention will be explained. The external magnetic sensing circuit 5 outputs an L level if the external magnetic field is below a set value, and outputs an H level if the external magnetic field is larger than the set value. Normally, when the external magnetic field is below the set value and the output of the external magnetic sensing circuit 5 is at L level, the output signal from the 1 second signal generating circuit 3 is G1,
The signal is input to the drive circuit 9 through the gate of G3 and operates the motor 10. Also, since the gate of G2 is closed, the 1 second signal is not input to counter 6,
Since the output of the coincidence circuit 7 is also at L level, the fast-forward signal from the fast-forward signal generating circuit 4 is also not input to the counter 8 and G3. Therefore, the clock moves in 1-second intervals. Next, when an external magnetic field exceeding the set value is applied, the output of the external magnetic sensing circuit 5 becomes H level, G1 is closed, and the 1 second signal is input to the counter 6 through G2. The output of the coincidence circuit 7 becomes H level, and the fast forward signal is input to G6, but since the other input terminal of G6 is at L level, the fast forward signal is not input to the counter 8 and G3. Therefore, the 1 second signal is stored in the counter 6, but the clock stops. Next, when the external magnetic field falls below the set value again, the output of the external magnetic sensing circuit 5 becomes L level, the 1 second signal is again input to the drive circuit 9 through G1 and G3, and the 1 second signal is no longer present. Since the input terminal of G6 connected to G1 becomes H level without being input to the counter 6, the fast-forward signal from the fast-forward signal generating circuit 4 is input to the counter 8 and G3. However, in order to prevent the 1-second signal and the fast-forward signal from overlapping, impingement is applied at the input terminal of G4 connected to the output terminal of G1. If the contents of the counters 6 and 8 match, the output of the matching circuit 7 becomes L level and the fast forward signal is no longer input to the counters 8 and G3. Therefore, the clock corrects the time by fast-forwarding the amount of time that it stopped when an external magnetic field with a value exceeding the set value is applied, when the external magnetic field falls below the set value again. Further, a time chart of each circuit shown in FIG. 1 is shown in FIG. 2.

Therefore, according to the circuit of the present invention, no matter how strong a magnetic field is applied, the correct time will be displayed when the magnetic field is removed again.

As described above, according to the present invention, a simple circuit not only eliminates the error in the time display of an electronic wristwatch caused by an external magnetic field, but also leads to the reduction of motor parts, cost reduction, miniaturization of the motor, and improvement of motor efficiency, which has great effects. has.

[Brief explanation of the drawing]

FIG. 1 is a circuit block diagram of one embodiment of the present invention. FIG. 2 is a timing chart of FIG. 1. DESCRIPTION OF SYMBOLS 1... Oscillation circuit, 2... Frequency division circuit, 3... 1 second signal generation circuit, 4... Fast forward signal generation circuit, 5...
...External magnetic sensing circuit, 6, 8...Counter, 7...
... Matching circuit, 9 ... Drive circuit, 10 ... Motor,
G1, G2, G4, G5, G6...AND gate, G3...OR gate.

Claims (1)

[Claims] 1 A time reference signal generating means, an electromechanical transducer, a drive circuit for driving the electromechanical transducer, an external magnetism detection means for detecting external magnetism and outputting a signal, and an electromechanical transducer for storing time information. storage means; and a first signal switching means connected to the time reference signal generation means to input a normal drive signal and output the normal drive signal to the drive circuit or the storage means based on the output of the external magnetic detection means. ,
A second drive signal connected to the reference signal generation means and having a period different from the normal drive signal is inputted, and the second drive signal is outputted to the drive circuit by the output of the external magnetic detection means and the storage means. and a second signal switching circuit for changing the normal drive signal from the drive circuit to the storage means and outputting it by the first signal switching means during the time when the external magnetic detection means detects magnetism of a certain value or more. However, when the magnetism changes from a certain amount or more to a certain amount or less, the first signal switching means applies the normal drive signal to the drive circuit again, and the second
An analog display electronic wristwatch characterized in that the second drive signal corresponding to the content stored in the storage means is inputted to the drive circuit by the signal switching means.