JP3144584B2 - Water supply control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a water supply control device which senses a user based on reflected light of intermittently projected light and automatically supplies water to a flushing machine such as a toilet or a hand washing machine. In particular, the present invention relates to an improvement in a water supply control device that reduces power consumption required for sensing a user.

[0002]

2. Description of the Related Art Conventionally, as this kind of water supply control apparatus, there is a water supply control apparatus which intermittently emits light at a predetermined cycle as described in Japanese Patent Application Laid-Open No. 61-294032.

FIG. 4 is a block diagram of a main part of a conventional sensing unit for performing such intermittent light emission. Conventional sensing unit 100
Is based on the output of the pulse generation circuit 101, and emits infrared light from the light emitting element 102 for about 140 μsec at a one-second cycle, for example, and reflects reflected light from a user (not shown) to the light receiving element 10
The light is converted into an electric signal by receiving the light at 3. The output of the light receiving element 103 is amplified by an amplifier circuit 104, and the auto-zero circuit 105 remembers the level of disturbance light such as sunlight or a fluorescent lamp immediately before the light is projected. The difference is detected, and the comparator 106 determines whether the difference exceeds a preset threshold value (reference voltage), and determines the presence or absence of a user to obtain a sensing output.

Japanese Patent Application Laid-Open No. 2-157332 discloses a technique for preventing a malfunction caused by disturbance light or the like by monitoring a light receiving output at a timing synchronized with a light emitting timing.

[0005]

However, since the conventional sensing unit determines the presence or absence of a user based on whether or not the light receiving level of the reflected light exceeds a threshold, disturbance light or the like synchronized with the light projection timing is not detected. If there is, there is a possibility that this is erroneously detected as a user. In particular, in order to further reduce the power consumption, if the sensitivity of the light receiving unit is increased by an amount corresponding to the reduction of the light emission amount by reducing the emission current of the light emitting element to secure a predetermined sensing range, S / N deteriorates and erroneous detection is likely to occur. The present invention has been made to solve such a problem, and an object of the present invention is to provide a water supply control device including a sensing unit that does not easily cause erroneous detection even when the amount of projected light is reduced.

[0006]

In order to solve the above-mentioned problems, in the water supply control apparatus according to the present invention, the sensing unit compares the light projection time and the reflected light reception time to determine the presence or absence of a sensing target. With.

[0007]

The sensing unit of the water supply control device according to the first aspect of the present invention compares the light projection time and the reflected light reception time to determine the presence or absence of a sensing target.

[0008] The sensing unit of the water supply control device according to the second aspect,
The light emitting means emits light modulated at a predetermined carrier frequency, and the light receiving means extracts a signal of a carrier frequency component from a light receiving output of the light receiving element, detects the light, and detects a time width of the output signal and a time of the light emitting signal. Compare with width.

[0009] The sensing unit of the water supply control device according to claim 3 is:
A plurality of lights having different light emission time lengths are emitted in bursts from the light emitting means at predetermined intervals, and the light receiving means determines each time length of the light receiving signal.

[0010]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a block diagram of a water supply control device according to the present invention.

The water supply control device 1 comprises a sensing unit 2 for sensing a user of the washing machine to be sensed, and a water supply control unit 3 for controlling water supply based on a signal from the sensing unit.

The sensing section 2 is a light projecting means 4 for emitting light, a light receiving means 5 for receiving light, and a judging means for judging the presence of the user 6 from the output signals of the light projecting means 4 and the light receiving means 5. A circuit 7 and a flip-flop 8 are provided.

The light emitting means 4 includes a clock generating circuit 41, a selecting circuit 42 for selecting an intermittent light emitting cycle, and an AND circuit 43.
And a light emitting circuit 44. FIG. 2 is a time chart showing the operation of the sensing unit.

The clock generation circuit 41 generates a master clock generated by using a crystal oscillator, a ceramic oscillator, or the like.
For example, FIG. 2A to FIG.
, A frequency dividing circuit for generating an intermittent light emitting clock signal 41b at the time of non-sensing, an intermittent light emitting clock signal 41c at the time of sensing, and the like.

In addition, the intermittent light emitting clock signal 4 when no sensing is performed
1b, as the intermittent light emitting clock signal 41c at the time of sensing,
Burst waves having different pulse widths as shown in FIGS. 2D and 2E can be used. Such a burst wave uses, for example, a counter and a flip-flop, sets the captured clock signal in the counter, sets the flip-flop at the beginning of a preset cycle, starts counting the clock signal, and sets the set value. When the time comes, the flip-flop is reset and waits for the beginning of the next cycle.

In this embodiment, the frequency of the carrier clock signal 41a is about 38 kHz, the intermittent light emission cycle when not sensing is about 2 seconds, and the intermittent light emission cycle when sensing is about 1 second. The selection circuit 42 outputs the intermittent light emitting clock signal 41b in the non-sensing state in the non-sensing state and the intermittent light emitting clock signal 41c in the sensing state in the non-sensing state based on the reflected light sensing state signal 81a supplied from the light emitting current increasing means 8. Select The selected intermittent light emission clock signal 42a is supplied to one input terminal of the AND circuit 43 and the comparison reference signal input terminal 7a of the judgment circuit 7.

A carrier clock signal 41a is supplied to the other input terminal of the AND circuit 43, and the intermittent light projecting clock signal 43a modulated by the carrier clock signal 41a.
Is supplied to the light emitting circuit 44 (see FIG. 2B or 2C). The light emitting circuit 44 includes a light emitting element 45 such as an infrared light emitting diode,
There is provided a constant current driving section including an npn transistor 46 and an emitter resistor 47 for determining a light projection current in a non-sensing state.

The light receiving means 5 includes a light receiving element 51 such as a PIN photodiode or a phototransistor, and a first-stage amplifier 52.
, A limiter circuit 53, and a band-pass filter (BPF)
This is a conventionally known configuration in which a combination of a detection circuit 54, a detection circuit 55, and a waveform shaping circuit 56 is provided. That is, the light receiving element 51
The first stage amplifier 52 converts the received light current into a voltage signal corresponding to the optical power of the light receiving element and amplifies it. The output voltage is limited in amplitude by a limiter circuit 53 so that the signal level becomes equal. Bandpass filter (B
PF) 54. Further, after demodulation by a detection circuit 55 such as a diode, an output signal 5 a of a predetermined logic level is output via a waveform shaping circuit 56.

The judgment circuit 7 has a comparison reference signal input terminal 7a
Is compared with the output signal 5a supplied to the reception signal input terminal 7b, and the input output signal 5a is synchronized with the intermittent light emission clock signal 42a corresponding to the light projection signal. When the pulse width of the output signal 5a is substantially equal to the pulse width of the intermittent light clock signal 42a, for example, the carrier clock signal 41a is provided a predetermined time after the rising of the intermittent light clock signal 42a.
At a timing similar to that of FIG.
g), and outputs a non-sense output 7d (see FIG. 2f) at the same timing at other times.

The flip-flop 8 is a set / reset type flip-flop (hereinafter, referred to as an RS flip-flop), and is based on a reflected light sensing state signal 8a output from an output terminal Q of the RS flip-flop 8. And the light emission cycle is switched.

While the user 6 or the like is being sensed, the sense output 7c is applied to the set input terminal S of the RS flip-flop 8.
Is supplied to a reset input terminal R to output a reflected light sensing state signal 8a from an output terminal Q of the RS flip-flop 8.

The water supply control section 3 includes a water supply control means 31 for controlling water supply to a flushing device such as a urinal based on a sensing output 7c and a non-sensing output 7d from the sensing section 2, and an on-off valve 32. The on-off valve 32 has one end connected to a water supply pipe 33 and the other end connected to a flusher (not shown) such as a urinal via a flush water supply pipe 34.

The opening / closing valve 32 is constituted by an electromagnetic valve using a so-called latching solenoid as an actuator, in which a pulse current is applied when the valve is opened and closed and the valve is opened or closed by a spring force or a magnetic force of a permanent magnet. I do. In addition, an actuator using a piezoelectric element is provided instead of the solenoid valve using a latching solenoid, and the valve opening is changed every time an open or close pulse is applied, and the valve opening at that time is maintained in a non-energized state. A valve having a structure may be used.

FIG. 3 is a time chart showing the operation of the water supply control unit. As shown in FIGS. 3A to 3C, the water supply control means 31 determines that the user is present when the sensing output 7c output from the determination circuit 7 continues for a certain period of time, and the non-sensing output 7d changes for a certain period of time. It is configured to judge that there is no user when continued.

When the water supply control means 31 determines that there is a user, as shown in FIGS. 3 (e) to 3 (g), it first generates a valve opening pulse 31b to open the on-off valve 32 and elapses a predetermined minute time. Thereafter, a valve closing pulse 31c is generated, and pre-wash water supply before use of the water washer is performed during this period.

Thereafter, the water supply control means 31 changes the valve opening pulse 31 when the judgment changes from the presence of the user to the absence of the user.
After b is generated to open the on-off valve 32 for a predetermined time, a valve-closing pulse 31c is generated to perform post-wash water supply. At the same time, the water supply control means 31 outputs a non-sensing state determination signal 31a shown in FIG.

With the above configuration, the water supply control device operates as follows. When the user is not detected, the reflected light sensing state signal 8a (the Q output of the RS flip-flop 8) is at the L level, and based on the reflected light sensing state signal 8a, the selection circuit 42 operates during the non-sensing state. The intermittent light emission period T is selected by selecting the intermittent light emission clock signal 41b.
Each time, light is modulated by the carrier clock signal 41a.

When the light receiving means 5 receives the reflected light and senses the presence of the user 6 or the like, the judgment circuit 7 outputs a sensing output 7c, sets the input terminal S of the RS flip-flop 8, and sets the reflection as the Q output. The light sensing state signal 8a is set to the H level. Thereby, the selection circuit 42 switches to the intermittent light emission clock signal 41c at the time of sensing, and the sensing interval is shortened to T / 2. This state continues until the user 6 or the like is not completely sensed.

The water supply control unit 3 performs pre-cleaning water supply when it senses that the user 6 or the like has approached by the sensing output 7c, and performs post-washing when it senses that the user 6 or the like has left by the non-sensing output 7d. Supply water. In addition, the structure which does not perform pre-wash water supply may be sufficient. Hereinafter, each time the user 6 or the like is sensed, the above operation is repeated.

In this embodiment, an example of the configuration using individual components has been described.
The determination circuit 7 and the water supply control means 31 of a may implement their functions by stored program control using, for example, a 4-bit one-chip microcomputer.

In the above embodiment, an example in which infrared light is used has been described. However, the present invention is not limited to this, and similar effects can be obtained by using other means such as ultrasonic waves.

[0032]

As described above, the sensing unit of the water supply control apparatus according to the first aspect of the present invention compares the light projection time with the reflected light reception time to determine the presence or absence of a sensing target. There is no erroneous detection of disturbance light having a different pulse width.

Also, unlike the conventional judgment based on the light receiving level, the judgment is made based on the pulse width of the light receiving signal. Therefore, the amount of projected light is reduced and the sensitivity of the light receiving means is set higher by that amount. Even if the light receiving signal is subjected to waveform shaping or the like, it is possible to reliably detect the sensing object without deteriorating the S / N.

The sensor of the water supply control device according to claim 2 is
The light emitting means emits light modulated at a predetermined carrier frequency, and the light receiving means extracts and detects a carrier frequency component signal from the light receiving signal of the light receiving element, and then detects the time width of the output signal and the time of the light emitting signal. Since the width and the configuration are compared, there is no erroneous detection due to disturbance light or the like other than the carrier frequency component.

If the receiving band is narrowed, the S / S
Since N can be improved, the amount of projected light can be further reduced, and the power consumption of the light projecting means can be further reduced.

The sensor of the water supply control device according to claim 3 is
The light emitting means emits a plurality of signals having different light emitting time lengths in a burst at predetermined intervals, and the light receiving means determines each time length of the plurality of received signals. Accuracy can be further improved.

[Brief description of the drawings]

FIG. 1 is a block diagram of a water supply control device according to the present invention.

FIG. 2 is a time chart illustrating an operation of a sensing unit.

FIG. 3 is a time chart showing an operation of a water supply control unit.

FIG. 4 is a block diagram of a main part of a conventional sensing unit.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Water supply control device, 2 ... Sensing part, 3 ... Water supply control part, 4 ...
Light emitting means, 5 ... Light receiving means, 6 ... User, 7 ... Judgment circuit,
8: set / reset type flip-flop (RS flip-flop), 31: water supply control means, 32: open / close valve,
33 ... water supply pipe, 34 ... washing water supply pipe, 41 ... clock generation circuit, 42 ... selection circuit, 43 ... AND circuit, 44 ... light emitting circuit, 45 ... light emitting element, 46, 83 ... transistor, 4
7, 82, 84: resistor, 51: light receiving element, 52: first-stage amplifier, 53: limiter circuit, 54: band-pass filter (BPF), 55: detection circuit, 56: waveform shaping circuit.

Continuation of the front page (72) Inventor Tomohiro Nishi 2-1-1 Nakajima, Kokurakita-ku, Kitakyushu-shi, Fukuoka Prefecture Totoki Co., Ltd. (56) References JP-A-2-209535 (JP, A) JP-A-Hei 2-85433 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) E03D 5/10 E03D 13/00 G01V 9/04

Claims (3)

(57) [Claims] 1. A sensing unit for detecting reflected light of light intermittently projected from a light projecting unit by a light receiving unit and outputting a sensing signal corresponding to an object to be sensed, and based on the sensing signal from the sensing unit. And a water supply control unit for controlling water supply, wherein the sensing unit includes a judging unit for judging the presence or absence of a sensing target by comparing the light projection time and the reflected light reception time. Water supply control device. 2. The light projecting means emits light intermittently at a preset carrier frequency for a preset light emitting time, and the light receiving means amplifies a light receiving output of a light receiving element and then performs amplitude limitation, The signal of the carrier frequency component is extracted from the output subjected to the amplitude limitation, the extracted signal is detected, the waveform is shaped, and an output signal is generated, and the determination unit determines the time width of the output signal and the emission signal. The water supply control device according to claim 1, wherein the water supply control device compares the time width. 3. The light emitting means emits a plurality of signals each having a different light emitting time length in a burst at predetermined cycles, and the judging means emits each of the plurality of signals received by the light receiving means. 3. The water supply control device according to claim 1, wherein a sensing output is generated when a time length of the water supply time corresponds to each of the light projection times. 4.