JPS5916834Y2 - time switching device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a time switching device suitable for use in power meters and the like, and more particularly to a time switching device in which a rotation detection circuit of a step motor is improved.

Conventionally, various types of electricity rate contracts have been concluded between power companies and electricity consumers, but these electricity rate contracts are divided into daytime and nighttime periods, and charges are increased for the amount of electricity used during the daytime. By making the weight higher than during the night, or during the day,
The power consumption is divided into three periods: nighttime and peak periods, and the power consumption is increased in the order of the time when the power consumption is the highest, in order to reduce power consumption. We are promoting this.

Therefore, in addition to the main electricity meter, the consumer side is equipped with a receiver that separately displays the amount of electricity during the day and night, and also has a connection between the electricity meter and the receiver. A time switching device is provided.

This time switching device mainly consists of a clock section, a step motor, a time zone dial board, and an output control relay, and is set at predetermined time intervals (for example, 15 minutes, 30 minutes, 60 minutes) from the clock section.
When the step motor is driven by driving the step motor and the time zone dial plate rotates to an angle corresponding to the time zone, for example, daytime or nighttime, the output control relay is switched and controlled. It is something to do.

As a result, the main watt-hour meter measures the total amount of electricity used, and in the daytime, the watt-hour meter outputs pulses proportional to the amount of electricity used through the output control relay to the receiver during the daytime. On the other hand, in the case of night time, a pulse proportional to the amount of power used in the time period is supplied to the night time power amount display section of the receiver via an output control relay. .

Here, the predetermined time interval is, for example, 15 minutes, 30 minutes, 60 minutes.
Minute means the minimum time unit. For example, if the daytime period is from 7:00 to 21:15 or 21:45, it is divisible by 15 minutes, so the minimum time unit is 15 minutes, and from 7:00 to 21:45.
If it is 1:30, it is divisible by 30 minutes, so the minimum time unit is 30 minutes, and if it is from 7:00 to 22:00, it is divisible by 30 or 60 minutes, so the minimum time unit is 30 minutes or 6.
It is set as 0 minutes.

In this way, since the step motor is rotated by a small angle at predetermined time intervals and the relay is controlled to operate when a predetermined time period is reached, there is an advantage that the battery power source of the power failure compensation battery can be made smaller.

The reason for this is that, rather than constantly driving a step motor that requires a large drive current in proportion to time, it is better to drive it intermittently by rotating it at a fixed angle at a faster speed every time period to keep up with time. This is because the calyx can be shortened.

FIG. 1 shows a configuration in which a step motor in a conventional time switching device is driven intermittently.

In other words, this device includes a timer circuit 3 that receives a reference pulse 1 obtained from a crystal oscillator or the like with high time precision, creates a timer signal, and resets the subsequent flip-flop circuit 2; A frequency divider circuit 5 divides the frequency of the pulse to a speed that drives the step motor 4, and a flip-flop circuit 2 outputs the divided output of the frequency divider circuit 5 when it reaches the H level to drive the step motor 4. Drive circuit 6
It consists of

7 is a rotation detection circuit for the step motor 4.

Now, when the time limit signal is output from the time limit circuit 3, the output terminal Q of the flip-flop circuit 2 is inverted from L level to H level.

This output terminal Q is connected to a drive circuit 6, and when the output terminal Q is at H level, the drive circuit 6 outputs a pulse for driving the step motor 4, thereby driving the step motor 4.

When the step motor 4 is driven and rotates once, the rotation detection circuit 7 outputs a rotation detection signal.

The rotation detection signal is input to the set terminal of the flip-flop circuit 2, and the output terminal Q is inverted from H level to L level.

When the output terminal Q of the flip-flop circuit 2 becomes L level, the output pulse from the drive circuit 6 is stopped, and in order to prevent current from flowing to the step motor 4, for example, all step motor drive transistors (not shown) are turned off. Step motor 4 is stopped.

Next, an example of a rotation detection circuit is shown in FIG.

That is, in this rotation detection circuit 7, a circular light shielding plate 8 having a notch 8a as shown in FIG. 3 is attached to the shirt 4a of the step motor 4. When the shirt 4a rotates, the light shielding plate 8 rotates in synchronization with the shirt 4a.

A light emitting diode 9 and a phototransistor 10 are arranged opposite to each other at the upper and lower parts of the light shielding plate 8, and the anode side of the light emitting diode 9 is connected to the positive polarity side of the power source via a resistor 11, and the cathode side is connected to the O potential side of the power source. It is connected to the.

On the other hand, the phototransistor 10 has its collector side connected to the positive polarity side of the power source, and its emitter side connected to the O potential side of the power source via the resistor 12.

With the above configuration, while the light shielding plate 8 passes between the light emitting diode 9 and the phototransistor 10, light is blocked and an L level rotation detection signal is generated between the emitter of the phototransistor 10 and the resistor 12. When the light shielding plate 8 further rotates and comes to the notch 8a, the light passes through and an H level rotation switching signal is output.

As a result, the step motor 4 is stopped until the next time signal arrives.

However, in the case of the rotation detection circuit 7 as shown in FIG. A sufficient current is passed through the phototransistor 10 because it is necessary to operate the phototransistor 10 in a stable light receiving operation for a long period of time.

As a result, the power consumption of the battery is relatively large, which is disadvantageous in that the compensation time in the event of a power outage is shortened.

For example, if the current flowing through the light emitting diode 9 is 1QmA, and the current consumption of other circuits is 1QmA, the power outage compensation time can be shortened to about 100% by constantly operating the light emitting diode.

The present invention was developed in view of the above-mentioned circumstances, and its purpose is to reduce the size of the battery power source by effectively supplying current to the light emitting diode and reducing power consumption. The present invention provides a time switching device that enables compensation for long-term power outages.

An embodiment of the present invention will be described below with reference to FIGS. 4 and 5.

These figures show a configuration in which the rotation detection circuit 7 in particular is improved in the apparatus shown in FIG.

Therefore, in FIGS. 4 and 5, the same parts as in FIGS. 1 to 3 are given the same reference numerals, and some explanations are omitted.

In FIG. 4, the shaft 4a of the step motor 4 includes:
An arc-shaped light-shielding plate 21 is attached, and a light-emitting diode 9 and a phototransistor 10 are mounted on the upper and lower parts of this light-shielding plate 21.
are placed facing each other.

Incidentally, the step motor 4 is provided with a time setting dial plate (not shown), and the switch is changed over using a setting pawl set on the dial plate.

The anode side of the light emitting diode 9 is connected to the positive electrode side of a battery power source via a resistor 11, and the cathode side is connected to the collector of a transistor 14.

Further, the emister side of the transistor 14 is connected to the O potential of the power supply.

The emitter side of the phototransistor 10 is connected to the O potential side of a power source, and the collector side is connected via a resistor 12 to the positive polarity side of a battery power source.

A rotation detection signal is output between the collector of the phototransistor 10 and the resistor 12, and the flip-flop circuit 2
is input to the set terminal of

A time signal is input to the reset terminal of the flip-flop circuit 2, and the output terminal Q of the flip-flop circuit 2 is connected to a drive circuit and to the base of a transistor 14 via a resistor 13.

The light shielding plate 21 shown in FIG. 4 has a cutout portion 2 as shown in FIG.
1 I have a.

Here, when the light shielding plate 21 is located between the light emitting diode 9 and the phototransistor 10, the light from the light emitting diode 9 is blocked and the phototransistor 10 is turned off.
The rotation detection signal becomes H level.

Further, when the cutout part 21a of the light shielding plate 21 is located between the light emitting diode 9 and the phototransistor 10, the light from the light emitting diode 9 is received by the phototransistor 10, and the phototransistor 10 is thereby turned on. A rotation detection signal of L level is output.

Next, the operation of the rotation detection circuit shown in FIG. 4 constructed as above will be explained.

When the time signal is input to the reset terminal of the flip-flop circuit 2, the output terminal Q changes from L level to H level.

When the output terminal Q of the flip-flop circuit 2 becomes H level, for example, a step motor drive transistor (not shown) of the drive circuit 6 operates, thereby outputting a step motor drive pulse, and the step motor 4 operates. , the transistor 14 is turned on, and a current flows through the light emitting diode 9 from the positive polarity side of the battery power source through the resistor 11, so that the light emitting diode 9 emits light.

Before the light emitting diode 9 emits light, the light shielding plate 21 is stopped between the light emitting diode 9 and the phototransistor 10.
When the step motor 4 operates, the light shielding plate 21 starts rotating, and after one revolution, it comes between the light emitting diode 9 and the phototransistor 10 again.

At this time, the rotation detection signal is still at H level while the light shielding plate 21 passes between the light emitting diode 9 and the phototransistor 10, but when the cutout 21a is positioned after passing, the phototransistor 10 is turned on. It becomes L level.

Then, the light shielding plate 21 rotates once, and the light emitting diode 9
and the phototransistor 10, it changes from L level to H level.

Then, the set terminal of the flip-flop circuit 2 becomes H level and the output terminal Q becomes L level, so that the drive circuit 6 stops outputting the step motor drive pulse.
The step motor 4 is stopped and, for example, all step motor drive transistors in the drive circuit 6 are turned off to prevent current from flowing through the step motor 4.

Further, the transistor 14 is turned off, and the light emitting diode 9 stops emitting light.

Note that since the flip-flop circuit 2 has reset priority, the rotation detection signal is set to H level while the light shielding plate 21 begins to rotate and the light shielding plate 21 is passing between the light emitting diode 9 and the phototransistor 10. However, since the time signal width is longer than the passing time, the step motor 4 is not stopped while passing the light shielding plate 21, but only rotates once and then stops.

As detailed above, according to the present invention, current is passed through the light emitting diode only when the step motor is operating, and no current is passed through the light emitting diode when the step motor is stopped until the next time signal arrives. In the event of a power outage, not only can the battery for power outage compensation be made smaller, but also long-term power outage compensation is possible.

In addition, the operating time of the light emitting diode has become very short (for example, if the step motor operates for 1 second in a 15-minute time limit, it will only operate for 4 seconds in 1 hour), and a time switching device that can improve reliability for long-term use has been developed. Can be provided.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of a typical step motor drive part of a time switching device, Fig. 2 is a diagram showing a specific structure of the conventional rotation detection circuit shown in Fig. 1, and Fig. 3 is a shading diagram shown in Fig. 2. The plan view of the plate, FIGS. 4 and 5, are for explaining the main parts of the present invention. FIG. 4 shows the configuration of an embodiment of the rotation detection circuit, and FIG. Plan view showing the plate, Figures 6 a-e
is a time chart explaining the operation of FIG. 4; 1...Reference pulse, 2...Flip
Flop circuit, 3...Timed circuit, 4...
・Step motor, 5... Frequency divider circuit, 6...
... Drive circuit, 7... Rotation detection circuit, 9...
...Light emitting diode, 10...Phototransistor, 14...Transistor, 21...
...Light shielding plate, 21a... Cutting part.

Claims (1)

[Scope of utility model registration request] The step motor is driven by a timed signal every predetermined time,
The rotational position of the step motor due to a predetermined rotation is optically detected, and the step motor is stopped based on the rotation detection signal to follow the time, and the time is set by a switching means attached to the rotating shaft of the step motor. In the switching device, a signal output circuit outputs a first signal in response to the time signal, a drive circuit that rotates the step motor a predetermined amount by a signal caused by the first signal of this circuit, and a switching element that turns on in response to a signal, a leading element that emits light when the switching element turns on, a light-receiving element that receives an optical signal from this element, and a light-receiving element arranged between the light-emitting element and the light-receiving element of the step motor. and a light shielding plate that shields the optical signal when the stepper motor is at a predetermined rotational position, and the stepper motor is stopped by outputting a second signal from the signal output circuit by the light shielding that occurs after the stepper motor has rotated the predetermined rotational position. Features a time switching device.