JPS5918394Y2 - electronic clock - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an electronic timepiece that uses a battery as a driving source and is equipped with a solar battery power source as an auxiliary power source.

The present invention automatically switches to the auxiliary power source to prevent the clock from stopping while replacing the main power battery, and by using the solar battery power source as the auxiliary power source, it only needs to be irradiated with light for a short time in advance. This invention relates to an electronic watch that allows the main power battery to be replaced at any time.

An object of the present invention is to replace the battery of the main power source without stopping the clock operation.

Considering quartz watches, which are the most accurate and most popular among electronic watches, quartz watches have some form of memory function.

In other words, they have functions such as calculation, alarm, and stopwatch functions, and among them there is a logical slow-speed type crystal clock that makes particular use of memory functions.

Furthermore, keeping time based on the starting point from which the time was set means memorizing the starting point in a broad sense, and all crystal watches have a memory function in a broad sense.

In the following, the present invention will be explained by taking as an example a crystal clock of a logical adjustment type, which is particularly closely related to memory functions.

As shown in Figure 1, in a conventional crystal clock, the output signal from the crystal oscillation circuit is 32768 Hz C or 16384 m.
).

This signal is frequency-divided and a 1-square signal is sent to the step motor.

Furthermore, within the display mechanism, the second signal, minute signal,
It creates and displays time signals.

In a crystal clock with such a configuration, the oscillation frequency of the oscillation circuit is 32768 Hz (or 1638 Hz) in any case.
4H2), and if the oscillation frequency deviates from this value, it will directly result in a clock error.

It is very difficult to adjust the oscillation circuit to set the oscillation frequency to a predetermined value.

For example, because the dimensional accuracy of a crystal resonator is strict, the frequency is ultimately finely tuned by trimming.

Therefore, manufacturing time is required and the yield of the vibrator is low.

In order to eliminate this drawback, a method using logical moderation has been proposed.

To briefly describe this principle, as shown in the block diagram of FIG. 2, the circuit consists of a memory, a comparator, and a frequency divider.

In the frequency adjustment operation, when the reset switch button is first pressed, the state of the frequency divider is returned to the zero state.

Therefore, when a standard signal as shown in FIG. 3A is applied to the gate Gl and the gate G1 is made conductive for a time T1, the frequency dividing circuit counts only the part shown by the solid line of the oscillator signal as shown in FIG.

Thereafter, the state of the frequency dividing circuit is stored in the memory circuit using gate G2, and gate G2 is closed.

If the number of pulses sent from the oscillator during time T1 when gate G1 is open is f, then the memory circuit stores the state when f pulses enter the frequency dividing circuit through the above operation. It turns out.

This completes the frequency adjustment operation.

Next, regarding the operation of the watch when carried, the gate G0 is always in a conductive state, the pulses from the oscillator go directly into the frequency divider, and the frequency divider counts the pulses of the oscillator.

The comparator compares the stored signal in the memory circuit with the operating state of the frequency divider circuit, and when the two match, that is, when f pulses have been input, it sends a reset signal to the frequency divider and sets the frequency divider to zero. Return to

If the circuit is configured so that when the frequency divider returns to the zero state, a pulse as shown in Figure 3C is output as an output, the pulse interval should be T1 as long as there is no frequency fluctuation of the oscillator. .

If T1 is selected so that the pulse shown in FIG. 3C becomes a second signal, and a minute signal and hour signal are created based on this, the clock can be operated.

Unlike the conventional method shown in Figure 1, the major advantage of this method is that the frequency of the oscillation circuit can be unique to each clock, and the oscillation frequency can be adjusted to 32,768 Hz < or 16,384 Hz as in the conventional method. It's not necessary.

Therefore, the requirement for dimensional accuracy of the vibrator is relaxed, leading to cost reduction.

Although it has such great advantages, it also has current problems.

It is desirable to use non-volatile memory as the memory element, but due to the high operating voltage and the large number of circuit elements at the current technological level, it is not possible to use non-volatile memory in wristwatches, so volatile memory is unavoidably used. It uses memory.

Therefore, when replacing the battery, the memory symbol disappears and the frequency adjustment operation must be performed again.

The present invention eliminates this drawback by switching to an auxiliary power source while replacing the battery, thereby preventing the memory symbol from disappearing.

Since the battery used for the auxiliary power source is the same whether it is a primary battery or a solar battery power source, the case where a solar battery power source is used will be described.

As is well known, the solar cell power supply includes a solar cell 1, a limiter circuit 2, a backflow prevention diode 3, as shown in FIG.
I am warning you from secondary battery 4.

In principle, the secondary battery 4 may not be needed as long as the solar battery is exposed to light while the main power battery is replaced.

Limiter circuit 2 is a circuit that prevents overcharging of the secondary battery.
Detects the potential at a point, and when this potential exceeds a certain value, a-
1) Conductivity occurs between the two, causing photocurrent to overflow.

When this circuit is used as an auxiliary power source for an electronic wristwatch, it is sufficient to use five 0.4 cm 2 silicon solar cells in series, and the area can be adapted to the wristwatch.

A solar cell with this area generates approximately 3 mA under direct sunlight.
A charging current of 1 to 2 mA can be obtained even outdoors in the shade, so
From an energy standpoint, if you carry it outdoors, you can use it as an auxiliary power source without having to consciously charge it.

Switching from the primary battery to the auxiliary power source can be easily done using a microswitch as shown in FIG.

Figure 5 shows only the part that incorporates the primary battery, which is the main power source of the wristwatch.

In Figure 5, 5 is part of the watch case, 6 is the battery, 7 is the battery holder lid, 8 is alumina porcelain, 9 is a spring, 10
is the lead terminal on the positive electrode side, 11 is the contact metal to the positive electrode side, 1
2 is a rubber O-ring that is glued to 11.

13 is a contact point of a microswitch.

The negative electrode of the primary battery 6 is connected to the negative side of the electronic circuit through the lid 7 and the case 5.

The positive electrode side is a contact metal 11. Spring 9 and lead terminal 10
It is connected to the positive side of the electronic circuit through the terminal, and is normally operated in this state.

In the solar cell power supply shown in FIG. 4, the C terminal is connected to the negative side of the electronic circuit, and the d terminal is connected to the contact 13 shown in FIG.

When the lid 7 is opened in this state, the battery 6 is pushed up by the spring 9.

When the contact metal 11 comes into contact with the contact point 13 due to the force of the spring, the power source of the electronic circuit is switched from the main power source to the auxiliary solar battery power source.

Conversely, if you push in a new battery, it will switch back to main power.

In order to prevent the contacts from momentarily separating due to the vibration of the spring and stopping the circuit, a capacitor with a large capacity is inserted between the input terminals of the electronic circuit, and when the power is cut off, the circuit is operated using the discharge of the capacitor. If so, the switching will be more reliable.

If the present invention and the conventional function of turning on an alarm indicator lamp when the electromotive force of the main power supply falls below a certain value are incorporated into a wristwatch, it is possible to replace the main power battery with a new one just before it runs out. It can be changed.

Furthermore, since the electronic circuit is operating during this time, it is possible to use logic regulation, which has been considered difficult in the past, in electronic watches.

The auxiliary power source may be a primary battery, but if a solar battery power source is used, there is no need to consciously charge the device when the device is carried outdoors.

Even if you cannot carry it outdoors, charging it for a few minutes under direct sunlight or indoor lighting will provide enough energy to replace the battery.

As described above, the present invention facilitates the production of a logical slow-speed wristwatch that does not require precision processing of the vibrator, and is of high value, but it can be considered to have a memory function in a broad sense.

This applies to all-crystal watches, and their value is high.

[Brief explanation of drawings]

Figure 1 is a block diagram of a conventional quartz wristwatch, Figure 2 is a block diagram of an electronic watch that uses logical adjustment until the second signal is extracted, and Figure 3 is a signal waveform at each point in the block diagram of Figure 2. a is the input waveform of the gate G1, b is the output waveform of the oscillator, and C is the output signal (second signal) from the frequency divider. FIG. 4 is a sectional view of the solar cell power supply circuit, and FIG. 5 is a sectional view of the part in which the main power battery of the wristwatch is installed.

Claims (1)

[Scope of utility model registration request] In an electronic clock having a logical adjustment function, the main power source consists of a primary battery for normal clock operation and a solar cell for operating the clock only when the secondary battery is removed for battery replacement. When the secondary battery is attached, the secondary battery pushes the main power supply electrically to the clock circuit, and when the primary battery is removed, it is moved by a spring to connect the auxiliary power supply to the clock circuit. An electronic timepiece characterized by having a power supply switching means made of a slidable contact metal electrically connected to the electronic timepiece.