JP3021253B2 - Object detection 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 object detecting apparatus, and more particularly, to projecting light onto an object such as a human body and detecting the presence or absence of the object by detecting the reflected light reflected by the projected light. It relates to a device for detecting.

[0002]

2. Description of the Related Art Conventionally, an object detecting apparatus for detecting an object by using reflection of infrared light has been widely used in various fields of consumer and industry.

In such an object detecting device, first, infrared light is projected from a light emitting element such as a light emitting diode. If there is any object such as a human body in the space where the infrared light is projected, the light projected from the light emitting element is reflected on the object. The presence or absence of an object is detected by detecting the reflected light with a light receiving element such as a photodiode. That is, when the light receiving element detects the reflected light, it is determined that an object is present, and when the reflected light is not detected, it is determined that the object is not present.

As a power source of such an object detection device,
Commercial power or batteries are used. When a battery is used as a power supply, it is common to use a battery having a long battery life such as a lithium battery and to suppress the consumption of the battery by intermittently emitting light from a light emitting element at a constant cycle. As a result, the battery life is made as long as possible and the trouble of replacing the battery is reduced.

[0005]

Incidentally, in the above object detecting device, infrared light generated by some external factor acts as a disturbance (hereinafter referred to as disturbance light), and accurate object detection may not be performed. .

The reason is that the light receiving element only outputs a detection signal when infrared light of a predetermined wavelength is received, and the received infrared light is reflected by the projected light from the light emitting element. This is because it does not have a function of determining whether the light is reflected light or disturbance light reflected on the object.

Therefore, when the wavelength of the disturbance light matches the wavelength of the projection light of the light emitting element, it can be determined whether an object actually exists or the disturbance light is generated. That is, accurate object detection cannot be performed.

In particular, in an inverter fluorescent lamp, since a specific lighting frequency is set by inverter control, disturbance light is generated in the same cycle as the lighting frequency. The present invention has been made to solve the above problems, and an object of the present invention is to provide an object detection device capable of accurately detecting an object even when disturbance light such as an inverter fluorescent light is generated. It is in.

[0009]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a light emitting device which emits light only once every time one pulse of a predetermined frequency is input. An object detection device that emits light from a light emitting element, and detects an object by detecting reflected light reflected from the object with a light receiving element by a light receiving element, outputs a pulse wave of a first set frequency. while a pulse wave generating means for outputting a pulse wave of a second set frequency, first, the operation of the pulse wave of the pulse wave generating means or we first set frequency that is a predetermined number of times output
Performed a predetermined number of times at regular intervals, then after a predetermined time, the pulse wave of the pulse wave generating means or al a second set frequency given
The operation of outputting the number of times is performed at a certain interval at a certain number of times.
There was provided a control determination unit that determines that all the light-receiving element a reflected light corresponding to the light emission of the light emitting element by the pulse wave of the first and second set frequency exists an object only when the received That is the gist.

The second invention projects light from a light emitting element which emits light only once each time one pulse of a pulse wave of a predetermined frequency is inputted, and the projected light In the object detection device configured to detect an object by detecting reflected light by a light receiving element, a pulse that outputs a pulse wave of a first set frequency and a pulse wave that outputs a pulse wave of a second set frequency and wave generating means, first, the pulse wave generating means or et first
Operation to output the pulse wave of the set frequency
Is performed a fixed number of times at regular intervals, and the first pulse wave
According to the case where the light receiving elements reflected light corresponding to the light emission of the light emitting element has all <br/> light is then fixed after time, pulse wave generating means or we second set pulse wave a predetermined number of times the output frequency
Operation is performed a fixed number of times at regular intervals, and the
The gist is that control judging means for judging that an object is present when the light receiving element receives all reflected light corresponding to light emission of the light emitting element by the two pulse waves is provided.

[0011]

In the first and second inventions, the light emitting element is
Each time one pulse of the pulse wave of the first and second set frequencies output from the pulse wave generating means is input, the light is emitted only once.

In the first invention, the control determination means
The stage firstly generates a pulse wave of the first set frequency.
The operation of outputting the number of times is performed at a certain interval at a certain number of times.
U. Next, after a lapse of a predetermined time, the control determination means performs an operation of outputting a pulse wave of the second set frequency a predetermined number of times.
Perform a certain number of times at regular intervals. Then, the control determining means includes:
The object is determined to be present only when the light receiving element receives all the reflected light corresponding to the light emission of the light emitting element by the pulse waves of the first and second set frequencies.

That is, light emission of the light emitting element in two stages
Are based on pulse waves that occur at a simple fixed period, respectively.
The reflected light corresponding to these emissions is not
Only when the object is detected
It is. Therefore, even if disturbance light occurs, the object can be accurately detected.
Can be issued.

In the second invention, the control determining means firstly outputs the pulse wave of the first set frequency for a predetermined number of times.
An operation of outputting a number is performed a fixed number of times at regular intervals.
When the light receiving element receives all the reflected light corresponding to the light emission of the light emitting element by the pulse wave of the first set frequency , the control determining means sets the pulse wave of the second set frequency to a predetermined value after a predetermined time has elapsed. One operation to output
Perform a certain number of times at regular intervals. Then, the control judging means controls the light emission of the light emitting element by the pulse wave of the second set frequency.
It is determined that an object is present only when all the corresponding reflected lights are received by the light receiving elements.

That is, also in the second invention, the first invention
As in the case of Ming, the light emission of the light emitting element in the two stages is respectively
It is not based on a pulse wave that occurs at a mere fixed period.
If all reflected light corresponding to these lights is received,
Only when the object exists, it is determined that the object exists. this
Therefore, even if disturbance light occurs, it is possible to accurately detect the object
it can.

In addition, in the second invention, the second light-emitting element is not used unless the light- receiving element receives all the reflected light corresponding to the light emission of the light-emitting element by the pulse wave of the first set frequency .
Do not emit light from the light emitting element by the pulse wave of the set frequency.
No. Therefore, power consumption can be reduced accordingly.
You.

[0017]

【Example】

(First Embodiment) A first embodiment in which the object detecting apparatus of the present invention is embodied as an automatic washing apparatus for a flush toilet for men (hereinafter referred to as a morning glory) will be described with reference to the drawings.

FIGS. 2 and 3 show the mounting state of the morning glory 1 of this embodiment. The morning glory 1 is attached to the front side of the wall surface 2 of the washroom, and an electromagnetic on-off valve 4 is connected to a water supply pipe 3 connected to the morning glory 1. When the electromagnetic on-off valve 4 is opened, washing water is supplied from the water supply pipe 3 to the morning glory 1. Conversely, when the electromagnetic on-off valve 4 is closed, the morning glory 1
The supply of the washing water to the is shut off.

The control box 5 has a wall 2 slightly above the morning glory 1.
Of the control box 5 is attached to the wall 2
It is exposed to. A human detection sensor 6 including a light emitting element 6a and a light receiving element 6b is provided on the front plate 5a.
A controller 7 and a lithium battery 8 are provided therein.

The light emitting element 6a is composed of a light emitting diode and emits infrared light having a preset wavelength. The light receiving element 6b is composed of a photodiode or a phototransistor, and outputs a detection signal only when infrared light having the same wavelength as the light projected from the light emitting element 6a is received.

FIG. 1 shows an electric block circuit of the automatic cleaning apparatus of this embodiment. The lithium battery 8 is connected to the controller 7
The power supply is supplied to the constant voltage circuit 20 and the valve drive circuit 21 therein.

The constant voltage circuit 20 is composed of a three-terminal regulator, and includes a microcomputer (hereinafter abbreviated as a microcomputer) 22 in the controller 7, a light emission drive circuit 23,
A stable DC voltage is supplied to each of the light receiving circuits 24.

The microcomputer 22 has a central processing unit (CP)
U), a read-only memory (ROM) storing a control program, a readable and writable memory (RAM) for temporarily storing a result of a human detection operation described later, an input / output interface, and the like.

Then, the microcomputer 22 performs a timer operation. Further, the microcomputer 22 outputs one of two types of light emission command signals F having different frequencies to the light emission drive circuit 23. That is, the frequency of the light emission command signal F is AK
There are two types, HZ and BKHz, and both have a duty of 50
% Pulse wave.

The light emission drive circuit 23 causes the light emitting element 6a to emit light based on a light emission command signal F from the microcomputer 22.
That is, the light emission drive circuit 23 causes the light emitting element 6a to emit light once each time one pulse of the light emission command signal F is input.

Therefore, the frequency AKHz
When the light emission command signal F is continuously output for a certain period of time, the light emission drive circuit 23 causes the light emitting element 6a to emit light a predetermined number of times. Also, the microcomputer 22 sends a light emission command signal F of a frequency BKHZ.
Is output for a certain period of time, the light emission drive circuit 23 also causes the light emitting element 6a to emit light a predetermined number of times.

The light receiving circuit 24 includes an amplifier 31 and a buffer 3
2 and 33, band pass filters 34 and 35, and waveform shaping circuits 36 and 37. The amplifier 31 amplifies the detection signal of the light receiving element 6b and outputs it to each of the buffers 32 and 33. Outputs of the buffers 32 and 33 are input to bandpass filters 34 and 35, respectively. The band-pass filter 34 includes the light-receiving element 6 amplified by the amplifier 31.
Of the detection signal b, only the signal of the frequency AKHz is filtered and passed. On the other hand, the band-pass filter 35 filters out only the signal of the frequency BKHZ out of the detection signal of the light receiving element 6b amplified by the amplifier 31, and passes it.
The waveform shaping circuits 36 and 37 respectively integrate the output signals of the band pass filters 34 and 35 and then shape the waveform to generate light receiving signals R1 and R2, which are output to the microcomputer 22.

That is, when a person is standing in front of the morning glory 1, the projection light from the light emitting element 6a reflects on the person. Then, the light receiving element 6b detects the reflected light and outputs a detection signal. Since the light emitting element 6a emits light in accordance with the pulse of the light emission command signal F, the light emission is not continuous, but the frequency (AKHZ or BK) of the light emission command signal F
HZ) is turned on and off with the lighting frequency. Therefore, the detection signal of the light receiving element 6b is not continuous, but corresponds to the frequency of the light emission command signal F.

Therefore, the light emission command signal F of the frequency AKHZ
When the light receiving element 6b receives the reflected light of the projection light of the light emitting element 6a due to the above, the frequency of the detection signal of the light receiving element 6b is also AK
HZ. Therefore, the detection signal of the light receiving element 6b is filtered by the band pass filter 34 and output from the waveform shaping circuit 36 as the light receiving signal R1. In addition, the frequency BKHZ
When the light receiving element 6b receives the reflected light of the projection light of the light emitting element 6a due to the light emission command signal F, the frequency of the detection signal of the light receiving element 6b also becomes BKHZ. Therefore, the light receiving element 6b
Is detected by the band pass filter 35 and output from the waveform shaping circuit 37 as the light receiving signal R2.

Here, the role of each of the waveform shaping circuits 36 and 37 is to integrate the detection signal of the discontinuous light receiving element 6b corresponding to the frequency of the light emission command signal F and then to shape the waveform, thereby forming a continuous light receiving signal. R1 and R2 are generated.

On the other hand, when no person stands in front of the morning glory 1, the light projected from the light emitting element 6a is not reflected. Then
Since the light receiving element 6b cannot detect the reflected light, it does not output the detection signal, and the light receiving circuit 24 does not output the light receiving signals R1 and R2.

The light receiving element 6b outputs a detection signal in the same manner regardless of whether the light reflected from the light projected from the light emitting element 6a is received or the disturbance light having the same wavelength as the light projected from the light emitting element 6a. I do. Therefore, when the AKHZ (or BKHZ) component is included in the lighting frequency of the disturbance light, the light receiving circuit 24 receives the reflected light of the light projected from the light emitting element 6a and the light receiving circuit 24 even when the disturbance light is received. Similarly, the light receiving signal R1 (or R2) is output.

The valve drive circuit 21 opens and closes the solenoid on-off valve 4 composed of a self-holding solenoid valve based on a command signal from the microcomputer 22. That is, each time the valve drive circuit 21 outputs a pulse-like timing signal, the electromagnetic on-off valve 4
The open / close state is switched, and when the timing signal is not output, the previous open / close state is held as it is.

Next, an operation for detecting whether or not a person is standing in front of the morning glory 1 in the embodiment configured as described above (hereinafter, referred to as a human detection operation) will be described with reference to a flowchart shown in FIG. I do.

First, in step (hereinafter referred to as S) 1, the microcomputer 22 sends the frequency AK to the light emission drive circuit 23.
The light emission command signal F of HZ is output a predetermined number of times at a predetermined interval at a time.

That is, the microcomputer 22 continues to output the light emission command signal F of the frequency AKHZ to the light emission drive circuit 23 for a certain period of time. Based on the light emission command signal F, the light emission drive circuit 23 causes the light emitting element 6a to emit light a certain number of times. Next, the microcomputer 22 waits until a certain time elapses, and after the certain time elapses, the frequency AKH
The light emission command signal F of Z is continuously output for a fixed time. Based on the light emission command signal F, the light emission drive circuit 23 causes the light emitting element 6a to emit light a certain number of times. And the microcomputer 22
Waits for a predetermined time to elapse again, and after the predetermined time elapses, keeps outputting the light emission command signal F of the frequency AKHZ to the light emission drive circuit 23 for a certain time. Based on the light emission command signal F, the light emission drive circuit 23 sets the light emitting element 6a
Is emitted a certain number of times.

Then, the flow shifts to S2. In S2,
The microcomputer 22 waits until a certain time elapses, and after the certain time elapses, proceeds to S3.

In step S3, the microcomputer 22 outputs a light emission command signal F having a frequency BKHZ to the light emission drive circuit 23 at predetermined times, at predetermined intervals, and at predetermined times. That is, the microcomputer 22 supplies the light emission drive circuit 23 with the frequency BK
The emission command signal F of HZ is continuously output for a fixed time. Based on the light emission command signal F, the light emission drive circuit 23 causes the light emitting element 6a to emit light a certain number of times. Next, the microcomputer 22 waits until a certain time elapses, and after the certain time elapses, continues to output the light emission command signal F of the frequency BKHZ to the light emission drive circuit 23 for the certain time again. Based on the light emission command signal F, the light emission drive circuit 23 causes the light emitting element 6a to emit light a certain number of times. Then, the microcomputer 22 waits again for a predetermined time, and after the predetermined time has elapsed, continuously outputs the light emission command signal F of the frequency BKHZ to the light emission drive circuit 23 for a certain time. Based on the light emission command signal F, the light emission drive circuit 23 causes the light emitting element 6a to emit light a certain number of times.

Then, the flow shifts to S4. In S4,
The microcomputer 22 controls the light emitting element 6a in S1 and S3.
It is determined whether or not the light receiving element 6b has received a certain number of times of light emission for a certain number of times at a certain interval, and whether or not the light receiving signals R1 and R2 have been output from the light receiving circuit 24 a certain number of times.

That is, in S1, the frequency AKHZ
When a person is standing in front of the morning glory 1 at the time when the light emitting element 6a is caused to emit light by the light emission command signal F, the light emitting element 6a
The reflected light from the person is reflected on the person. Then, the light receiving element 6b detects the reflected light and outputs a detection signal of the frequency AKHz. The detection signal is filtered by the band-pass filter 34 and output from the waveform shaping circuit 36 as the light receiving signal R1. Since the light emission command signal F is output at a constant interval and a certain number of times, the light receiving signal R1 is also output at a certain interval and a certain number of times.

After a lapse of a predetermined time in S2, S
In 3, when the light emitting element 6a is caused to emit light by the light emission command signal F of the frequency BKHZ, if a person stands in front of the morning glory 1, the projection light from the light emitting element 6a reflects on the person. Then, the light receiving element 6b detects the reflected light and outputs a detection signal of the frequency BKHZ. The detection signal is filtered by the band pass filter 35 and output from the waveform shaping circuit 37 as a light receiving signal R2. Since the light emission command signal F is output at a constant interval and a certain number of times, the light receiving signal R2 is also output at a certain interval and a certain number of times.

Therefore, the light receiving signal R1,
If R2 is output a certain number of times, morning glory 1
It can be seen that a person is standing for more than a certain time in front of. On the other hand, if the light receiving signals R1 and R2 are not output from the light receiving circuit 24 for a certain number of times, it is understood that no person has appeared before the morning glory 1 for a certain time or more.

When the light receiving signal R1 is output a fixed number of times, but the light receiving signal R2 is not output a certain number of times,
It can be seen that the person simply crossed the front of the morning glory 1 or that the received light signal R1 is not due to the light emission of the light emitting element 6a but to the disturbance light.

Similarly, if the light receiving signal R2 is output a fixed number of times, but the light receiving signal R1 is not output a certain number of times, a person has just appeared before the morning glory 1, or
It can be seen that the light receiving signal R2 is not due to the light emission of the light emitting element 6a but to the disturbance light.

Further, each of the light receiving signals R1 and R2 is 1
When the output is performed twice or less, it is understood that the output is not due to the light emission of the light emitting element 6a but to the disturbance light. That is, even when disturbance light is generated, the disturbance light is generated a certain number of times at a certain interval, and is unlikely to coincide with the light emission of the light emitting element 6a. Therefore, the light receiving signals R1,
When R2 is due to disturbance light, the received light signals R1, R
2 is not output at a fixed number of times.

Then, the light receiving signal R1,
If R2 has been output a predetermined number of times, the process proceeds to S5, and if one or both of the light receiving signals R1 and R2 have not been output a predetermined number of times, the process proceeds to S6.

In step S5, the microcomputer 22 determines that a person is standing in front of the morning glory 1 and determines "person detection", and stores the determination result in the RAM. Then, the process proceeds to S7. On the other hand, in S6, the microcomputer 22 determines that no person is standing in front of the morning glory 1 and determines “non-detection”, and stores the determination result in the RAM. Then, the process proceeds to S7.

In S7, the microcomputer 22 waits until a predetermined time has elapsed, and returns to S1 after the predetermined time has elapsed. As described above, in this embodiment, first, the light-emitting element 6a emits light a fixed number of times at a fixed interval by the light-emitting command signal F having the frequency AKHZ. Then, after a certain time, the frequency B
The light emitting element 6a is caused to emit light a certain number of times at a certain interval according to a light emission command signal F of KHz. Since the light emission command signal F is output at a constant pulse every time, the light emitting element 6a emits light a certain number of times each time based on the number of pulses of the light emission command signal F.

The microcomputer 22 uses these two frequencies (A
KHZ and BKHZ), a person stands in front of the morning glory 1 only when the light receiving circuit 24 outputs the light receiving signals R1 and R2 a certain number of times, respectively, in response to the light emission by the light emitting command signal F of KHZ and BKHZ). Human detection ”).

On the other hand, the microcomputer 22 determines that the light receiving circuit 24 does not output both or one of the light receiving signals R1 and R2 from the light receiving circuit 24 a certain number of times in response to the light emission by the light emitting command signal F of two kinds of frequencies. Determines that no person is standing in front of the morning glory 1 (that is, “people not detected”).

When an inverter fluorescent lamp is used as the illumination of the place where the automatic morning glaze washing device 1 is installed, the inverter fluorescent lamps with lighting frequencies of AKHz and BKHz are rarely mixed. Therefore, even if the lighting frequency of the inverter fluorescent lamp matches one frequency (AKHz or BKHz) of the light emission command signal F, it does not match the other frequency. for that reason,
The disturbance light from the inverter fluorescent lamp is not erroneously determined as “human detection” as reflected light of the projection light from the light emitting element 6a.

The light receiving circuit 24 receives light signals R1 and R2 from the light receiving circuit 24 for a predetermined number of light emissions of the light emitting element 6a at fixed intervals.
Is determined as "human detection" only when each of them is output a certain number of times (that is, when the light receiving elements 6b can all receive the certain number of times). That is, even when disturbance light occurs, the disturbance light is generated a certain number of times at certain intervals,
In addition, the light emission of the light emitting element 6a is unlikely to match.
Therefore, when the light receiving signals R1 and R2 are caused by disturbance light, the light receiving signals R1 and R2 are not output at a certain number of times. Therefore, even for disturbance light due to any cause other than the inverter fluorescent lamp, the disturbance light is not mistaken for the reflected light of the projection light from the light emitting element 6a.

As described in detail above, in this embodiment,
Even if disturbance light is generated by an inverter fluorescent lamp or the like, a person standing in front of the morning glory 1 can be accurately detected without being affected by the disturbance light.

When the result of the determination of "human detection" follows the result of the determination of "human non-detection", the microcomputer 22
Performs a pre-cleaning process. That is, the microcomputer 22 controls the valve drive circuit 21 to open the electromagnetic opening / closing valve 4 for a certain period of time to supply a certain amount of washing water from the water supply pipe 3 to the morning glory 1 to wash the morning glory 1. As a result, it is possible to comfortably add small items and to make the morning glory 1 difficult to stain.

Subsequently, when a determination result of "human detection" follows a determination result of "human detection", the microcomputer 22
Determines that the person who has completed the addition has left before the morning glory 1, and performs post-cleaning processing.

That is, the microcomputer 22 controls the valve drive circuit 2
By controlling the valve 1, the electromagnetic opening / closing valve 4 is opened for a predetermined time so that a certain amount of washing water is supplied from the water supply pipe 3 to the morning glory 1, and the morning glory 1 is washed.

As described above, in the apparatus for automatically cleaning morning glory 1, when a person who wants to add a small person stands in front of morning glory 1,
After cleaning (pre-cleaning) and adding small items
After that, the morning glory 1 is washed again (post-washing process) when the user leaves from the front.

(Second Embodiment) Next, a description will be given of a second embodiment in which the object detection apparatus of the present invention is embodied as an automatic morning glory cleaning apparatus with reference to the drawings.

The configuration of this embodiment is completely the same as that of the first embodiment, and the only difference is the operation of the microcomputer 22. Therefore, the configuration of the present embodiment has the same reference numerals as those of the first embodiment, and the description thereof will be omitted.

Hereinafter, the human detecting operation of the present embodiment will be described with reference to the flowchart shown in FIG. First, S1
In step 1, the microcomputer 22 outputs a light emission command signal F having a frequency AKHZ to the light emission drive circuit 23 at a certain time and a certain number of times.

That is, the microcomputer 22 continues to output the light emission command signal F of the frequency AKHZ to the light emission drive circuit 23 for a certain period of time. Based on the light emission command signal F, the light emission drive circuit 23 causes the light emitting element 6a to emit light a certain number of times. Next, the microcomputer 22 waits until a certain time elapses, and after the certain time elapses, the frequency AKH
The light emission command signal F of Z is continuously output for a fixed time. Based on the light emission command signal F, the light emission drive circuit 23 causes the light emitting element 6a to emit light a certain number of times. And the microcomputer 22
Waits for a predetermined time to elapse again, and after the predetermined time elapses, keeps outputting the light emission command signal F of the frequency AKHZ to the light emission drive circuit 23 for a certain time. Based on the light emission command signal F, the light emission drive circuit 23 sets the light emitting element 6a
Is emitted a certain number of times.

Then, the flow shifts to S12. In S12, the microcomputer 22 determines that the light receiving element 6b receives all of the light emitted by the light emitting element 6a in the fixed number of times at the fixed interval in S11, and the light receiving circuit 24 receives the light receiving signal R1 from the light receiving circuit 24.
It is determined whether or not is output a certain number of times.

That is, when a person is standing in front of the morning glory 1, the projection light from the light emitting element 6a reflects on the person. Then, the light receiving element 6b detects the reflected light and outputs a detection signal of the frequency AKHz. The detection signal is filtered by the band-pass filter 34 and output from the waveform shaping circuit 36 as the light receiving signal R1. The light emission command signal F
Are output a fixed number of times at fixed intervals, so that the light receiving signal R1 is also output a fixed number of times at fixed intervals.

When no person stands in front of the morning glory 1, the light projected from the light emitting element 6a is not reflected and the light receiving element 6a is not reflected.
b does not output a detection signal because reflected light cannot be detected.
Therefore, the light receiving circuit does not output the light receiving signal R1.

Further, even when disturbance light is generated, the disturbance light is generated a certain number of times at a certain interval.
It hardly matches the light emission of a. Therefore, when the light receiving signal R1 is output a certain number of times at a certain interval, it can be understood that the light receiving signal R1 is not due to disturbance light but due to reflected light of the light projected from the light emitting element 6a.

When the light receiving signal R1 has been output from the light receiving circuit 24 for a fixed number of times, the flow shifts to S13, where the light receiving signal R1 is output.
If 1 has not been output a certain number of times, the process proceeds to S14. In S13, the microcomputer 22 waits until a certain time elapses, and after the certain time elapses, proceeds to S15.

In step S15, the microcomputer 22 outputs a light emission command signal F having a frequency BKHZ to the light emission drive circuit 23 at a certain time and a certain number of times. That is, the microcomputer 22 supplies the light emission drive circuit 23 with the frequency B
The light emission command signal F of KHz is continuously output for a fixed time.
Based on the light emission command signal F, the light emission drive circuit 23 causes the light emitting element 6a to emit light a certain number of times. Next, the microcomputer 22
Waits for a predetermined time to elapse, and after the predetermined time elapses, continuously outputs the light emission command signal F having the frequency BKHZ to the light emission drive circuit 23 for the certain time. Based on the light emission command signal F, the light emission drive circuit 23 causes the light emitting element 6a to emit light a certain number of times. Then, the microcomputer 22 waits again for a predetermined time, and after the predetermined time has elapsed, continuously outputs the light emission command signal F of the frequency BKHZ to the light emission drive circuit 23 for a certain time. Based on the light emission command signal F, the light emission drive circuit 23 causes the light emitting element 6a to emit light a certain number of times.

Then, the flow shifts to S16. In S16, the microcomputer 22 determines that the light receiving element 6b receives all of the light emitted by the light emitting element 6a in the fixed number of times at the fixed interval in S15, and the light receiving circuit 24 receives the light receiving signal R2 from the light receiving circuit 24.
It is determined whether or not is output a certain number of times.

That is, when a person is standing in front of the morning glory 1, the projection light from the light emitting element 6a is reflected on the person. Then, the light receiving element 6b detects the reflected light and outputs a detection signal of the frequency BKHZ. The detection signal is filtered by the band pass filter 35 and output from the waveform shaping circuit 37 as a light receiving signal R2. The light emission command signal F
Is output a fixed number of times at fixed intervals, so that the light receiving signal R2 is also output a fixed number of times at fixed intervals.

When no person stands in front of the morning glory 1, the light projected from the light emitting element 6a is not reflected and the light receiving element 6a is not reflected.
b does not output a detection signal because reflected light cannot be detected.
Therefore, the light receiving circuit does not output the light receiving signal R2.

Further, even when spontaneous disturbance light is generated, the disturbance light is generated a certain number of times at a certain interval, and is unlikely to coincide with the light emission of the light emitting element 6a. Therefore,
When the light receiving signal R2 is output a certain number of times at a certain interval, it can be understood that the light receiving signal R2 is not due to disturbance light but due to reflected light of the light projected from the light emitting element 6a.

If the light receiving signal R2 has been output from the light receiving circuit 24 for a fixed number of times, the flow shifts to S17, where the light receiving signal R2 is output.
If 2 has not been output a fixed number of times, the process proceeds to S14. In S17, the microcomputer 22 determines that a person is standing in front of the morning glory 1 and determines that “human detection”, and stores the determination result in the RAM. Then, control goes to a step S18.

On the other hand, in S14, the microcomputer 22 determines that no person is standing in front of the morning glory 1 and determines "non-detection", and stores the determination result in the RAM. And S18
Move to.

In S18, the microcomputer 22 waits until a predetermined time has elapsed, and returns to S11 after the predetermined time has elapsed.
As described above, in this embodiment, first, the frequency AKHZ
The light-emitting element 6a emits light a certain number of times at a certain interval according to the light-emitting command signal F. When the light receiving signal R1 is output from the light receiving circuit 24 a certain number of times in response to the light emission of the light emitting element 6a, after a certain period of time, the light emitting element 6a is then moved at regular intervals by the light emitting command signal F having the frequency BKHZ. Emit light a certain number of times. When the light receiving signal R2 is output from the light receiving circuit 24 for a certain number of times with respect to the light emission of the light emitting element 6a, the microcomputer 22 determines that a person is standing in front of the morning glory 1 (that is, “human detection”). .

If the light receiving circuit 24 does not output the light receiving signal R1 a fixed number of times for the light emitting of the light emitting element 6a by the light emitting command signal F of the frequency AKHz, the microcomputer 22
Determines that no person is standing in front of the morning glory 1 (that is, “people not detected”).

Further, the light emission command signal F of the frequency BKHZ
When the light receiving circuit 24 does not output the light receiving signal R2 a fixed number of times in response to the light emission of the light emitting element 6a, the microcomputer 22 also determines that "a person is not detected".

Since the light emission command signal F is output at a constant pulse every one time, the light emitting element 6a emits light a certain number of times at one time based on the number of pulses of the light emission instruction signal F. That is, in the first embodiment, the light emission by the light emission command signal F at the frequency AKHz and the light emission by the light emission command signal F at the frequency BKHz are repeatedly performed at regular intervals.
On the other hand, in the present embodiment, the light emission command signal F of the frequency BKHz is provided only after the light emission command signal F of the frequency AKHZ has been able to receive all of the light emission of a certain number of times at a certain interval. To emit light.

That is, in order to obtain the result of the determination of “human detection”, in the present embodiment, as in the first embodiment, two
Light emission must be performed by the light emission command signal F of different frequencies (AKHz and BKHz). Therefore, in the present embodiment, the same effects as in the first embodiment can be obtained.

On the other hand, in the case where the determination result of "human detection" is given, in the first embodiment, the light emission by the emission command signal F of two kinds of frequencies is performed in the same manner as in the case of giving the determination result of "human detection". Have to go through. However,
In the present embodiment, if the light emission command signal F of the frequency AKHZ emits light for a certain number of times at a certain interval and cannot receive all of the lights for a certain number of times, it is determined that the person is not detected.
Can be obtained.

That is, in this embodiment, the frequency BKHZ
The determination result of “human non-detection” can be obtained without performing light emission by the light emission command signal F. Therefore, in the present embodiment, the determination result of “non-human detection” can be obtained earlier than in the first embodiment.

The other operations (pre-cleaning process and post-cleaning process) and effects are the same as those of the present embodiment and the first embodiment, and therefore the description thereof is omitted here. The present invention is not limited to the above embodiments, but may be implemented with the following changes.

1) The frequency (AKHZ and BKHZ) of the light emission command signal F is set to an appropriate frequency within a range different from the lighting frequency of the inverter fluorescent lamp. Further, the frequency of the light emission command signal F is not two but three or more, and the same as in the above embodiment.

2) Instead of causing the microcomputer 22 to perform a timer operation, a timer circuit is provided as a peripheral circuit of the microcomputer 22 and the timer circuit performs the timer operation. 3) The pre-cleaning process is performed when the determination result of “human detection” continues twice after the determination result of “non-human detection”. After the determination result of “human detection” is followed by the determination result of “non-human detection” twice, the post-cleaning process is performed. In this case, even if the person simply crosses in front of the morning glory 1 or the body of the person shakes during small use, the person detection operation can be performed more reliably, and the pre-cleaning process and the post-cleaning process are performed incorrectly. To do it.

4) The light emission command signal F is not a pulse wave having a duty of 50% but a pulse wave having an arbitrary duty. 5) Replace the lithium battery 8 with a DC power supply and supply power from a commercial power supply.

6) Use visible light or ultraviolet light instead of infrared light. That is, the light emitting element 6a projects visible light or ultraviolet light instead of infrared light, and the light receiving element 6b receives the projected light and outputs a detection signal.

7) Ultrasonic waves are used instead of light. That is, the light emitting element 6a is replaced with an ultrasonic speaker, and the light receiving element 6b is replaced with an ultrasonic microphone. Further, the circuit configurations of the light receiving circuit 24 and the light emitting circuit 23 are appropriately changed. Then, a sound wave reflected from the ultrasonic speaker from the ultrasonic speaker hits the object is detected by the ultrasonic microphone.

8) The present invention is embodied not only in the morning glory 1 but also in an automatic washing apparatus for various sanitary appliances such as a wash basin. 9) Not only an automatic cleaning device for sanitary appliances but also other object detection devices such as automatic doors and FA devices.

10) The above-mentioned 1) to 9) are carried out by appropriately combining them.

[0089]

As described above in detail, according to the present invention, there is an excellent effect that an object can be accurately detected even when disturbance light is generated by an inverter fluorescent lamp or the like.

[Brief description of the drawings]

FIG. 1 is an electric block circuit diagram of first and second embodiments in which the present invention is embodied in an automatic flushing device for a men's flush urinal (morning glory).

FIG. 2 is a partially cutaway side view showing an attached state of a men's flush urinal (morning glory) of the first and second embodiments.

FIG. 3 is a front view of the men's flush urinal (morning glory) shown in FIG. 2;

FIG. 4 is a flowchart illustrating a human detection operation in the first embodiment.

FIG. 5 is a flowchart illustrating a human detection operation in the second embodiment.

[Explanation of symbols]

6a: light emitting element, 6b: light receiving element, 22: microcomputer as pulse wave generating means and control determining means, 23: light emitting drive circuit as pulse wave generating means

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-2-157333 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G01V 8/10 E03D 5/10

Claims (2)

(57) [Claims] 1. A light is emitted from a light emitting element (6a) that emits light only once each time one pulse of a pulse wave of a predetermined frequency is input, and the projected light is reflected on an object. In an object detection device configured to detect an object by detecting reflected light with a light receiving element (6b), a pulse that outputs a pulse wave of a first set frequency and outputs a pulse wave of a second set frequency Wave generation means (2
And 2,23), first, pulse wave generating means (22, 23) or al first
Operation to output the pulse wave of the set frequency
Perform a certain number of times created at regular intervals, then after a predetermined time, the pulse wave generating means (22, 23) or al pulse wave of a second set frequency operation of causing output a predetermined number of times a certain
The object is performed a certain number of times at each interval, and only when the light receiving element (6b) receives all the reflected light corresponding to the light emission of the light emitting element (6a) by the pulse waves of the first and second set frequencies. object detecting apparatus characterized by but provided with a control determination means for determining a present (22). 2. A light is emitted from a light emitting element (6a) which emits light only once each time one pulse of a pulse wave of a predetermined frequency is inputted, and the projected light is reflected on an object. In an object detection device configured to detect an object by detecting reflected light with a light receiving element (6b), a pulse that outputs a pulse wave of a first set frequency and outputs a pulse wave of a second set frequency Wave generation means (2
And 2,23), first, pulse wave generating means (22, 23) or al first
Operation to output the pulse wave of the set frequency
Is performed a fixed number of times at regular intervals, and the first pulse wave
According to the case where the light receiving elements reflected light corresponding to the light emission of the light emitting element (6a) (6b) has received all, then, after a predetermined time has elapsed, the pulse wave generating means (22, 23) or these second set frequency One operation is to output the pulse wave a predetermined number of times.
This is performed a fixed number of times at regular intervals, and reflected light corresponding to light emission of the light emitting element (6a) by the second pulse wave is received by the light receiving element (6).
An object detection device, comprising: a control determining means (22) for determining that an object is present when all the light is received.