JPH09168581A - Control circuit for automatic deodorizer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control circuit for an automatic deodorizer with reduced malfunction caused by external light or disturbance and improved reliability by equipping a human body detection means and disturbance light detection means, comparing each of signal levels, and controlling the drive of an automatic deodorizer according to the comparison result. SOLUTION: When a signal emitting element 19 of a signal emitting/receiving circuit 12 is active (to emit light), the emitting light from the signal emitting element 19 is detected by a signal receiving element 21 and switched by an analog switch and held in a first signal level holding circuit 28 of a human body existence judging circuit 13. On the other hand, when inactive, peripheral light and disturbance light detected by the signal receiving element 21 are switched by a switch and held in a second signal level holding circuit 31. Then the reflected light level held by the first signal level holding circuit 23 and the disturbance light level held by the second signal level holding circuit 31 are compared by a comparator 32. When the received light level is equal to or greater than a prescribed value, it is judged that a human body exists to drive an automatic deodorizer drive circuit 14 and odor is adsorbed by a fan.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control circuit for an automatic deodorizer which detects the approach of a human body and automatically controls the deodorizer. Since the automatic deodorizer detects the reflected light from the human body and determines the presence or absence of the human body, it activates the automatic deodorizer.Therefore, natural light such as sunlight, artificial light such as fluorescent lights, or the background of walls, etc. Therefore, malfunction due to ambient light is not allowed.

[0002]

2. Description of the Related Art FIG. 4 is a diagram showing an example of a conventional control circuit for an automatic deodorizer. Many conventional automatic deodorizer drive circuits control the deodorizer by detecting the reflected light from the human body when the human body approaches the deodorizer.

In this automatic deodorizer, the signal emitting element 1
Infrared light is emitted from 9 and is detected by an optical signal incidence element 21 reflected by an approaching human body to automatically start absorbing odors. When using light, natural light such as sunlight (DC)
Artificial light (such as AC 50Hz or 60Hz and its harmonics) such as a fluorescent lamp or a fluorescent lamp is modulated by a modulator 16 that is modulated at a frequency that can be discriminated from these lights so as not to operate by mistake, and then demodulated by a demodulator 23 and modulated. The light level and a predetermined reference threshold level are compared by the comparator 32. When the light receiving level is higher than the threshold level, it is determined that the human body is approaching, and the automatic deodorizer of the next stage. The drive circuit 14 is driven to turn on the display LED 34 and rotate the fan to absorb the odor.

[0004]

[Problems to be Solved by the Invention] In an automatic deodorizer,
Detecting the approach of a human body using the modulation / demodulation circuit 11 described above is useful for preventing erroneous detection of the human body due to the artificial light described above. However, looking at the situation where the background such as the wall near the automatic deodorizer has a bright color and a person is wearing dark clothes, the modulated light reflected from the background or the reflection level of the modulated light is reflected. On the other hand, since the reflection level of the modulated light or the modulated wave reflected from the human body that is close to the object is small, the reflection from the background is erroneously determined as the reflection from the human body that is close to it, and the automatic deodorizer malfunctions. there were.

Therefore, according to the present invention, the presence / absence of a human body is judged by emitting a signal (light) from the automatic deodorizer (signal emitting element 19), reflecting it by an approaching human body, and detecting it by the signal incident element 21. With the control circuit for the automatic deodorizer, in addition to the conventional modulator / demodulator circuit 11 and the signal input / output circuit 12, the presence or absence of the human body is detected by detecting the intensity of the reflected light from the background such as the wall near the automatic deodorizer or the disturbance light. It is an object of the present invention to provide a control circuit for an automatic deodorizer, which can identify the above and prevent the automatic deodorizer from erroneously operating due to reflection from the background.

[0006]

FIG. 1A is a diagram showing the basic configuration of a control circuit for an automatic deodorizer when light is used as a medium according to the present invention. The same components as those already described in FIG. 4 are designated by the same reference numerals or symbols. The basic configuration of the present invention is configured in the same manner as the conventional one, but in the past, the comparison of reflected light vs. reference light level was detected by comparison of (reflected light + reference level) vs (reference level + disturbance light). doing.

Light is emitted from the human body detecting means 1 and the comparing means 3 compares the reflected light from the human body with the ambient light such as natural light or artificial light to judge the presence or absence of the human body. To operate. FIG. 1B is a diagram showing a basic configuration of an automatic deodorizer control circuit when ultrasonic waves are used as a medium according to the present invention. In this case, ultrasonic waves are used as a medium instead of light, and the presence or absence of a human body is determined by comparing the reflected sound from the human body and the disturbance sound from the surroundings with the comparison means 3, and the driving means 4 is operated when a human is present. Let

[0008]

FIG. 2 is a diagram showing a first embodiment according to the present invention. The significance of this first embodiment is as follows. According to the first embodiment of the present invention, it comprises a modulation / demodulation circuit 11, a signal input / output circuit 12, a human body presence / absence judgment circuit 13, and an automatic deodorizer drive circuit 14.

When the signal emitting element 19 is active (when light is emitted from the signal emitting element 19), the light emitted from the signal emitting element 19 is detected by the signal incident element 21,
It is switched by an analog switch and held in the first signal level holding circuit 28. When it is inactive (when the light is not emitted from the signal emitting element 19), the ambient light and the disturbance light detected by the signal incident element 21 are switched by the analog switch and are held in the second signal level holding circuit 31, and 1
The comparator 32 compares the reflected light level held by the signal level holding circuit 28 with the disturbance light level held by the second signal level holding circuit 31, and when the received light level is higher than a certain value, it means that a human body exists. It is judged that the automatic deodorizer drive circuit 14 is driven, the fan is rotated to adsorb the odor, and the display LED 34 is turned on if necessary to indicate that it is in operation.

Thus, according to the first embodiment of the basic configuration of the present invention, it is possible to prevent malfunction by detecting reflected light from a wall or the like and ambient light near the automatic deodorizer. FIG. 3 is a diagram showing a second embodiment according to the present invention. The significance of this second embodiment is as follows. According to the second embodiment of the present invention, the modulation / demodulation circuit 11, the signal input / output circuit 12, the human body presence / absence determination circuit 13, and the automatic deodorizer drive circuit 1 which are the same as those of the first embodiment.
In addition to 4, the second signal incidence element 22 for exclusively detecting ambient light and ambient light is separately provided.

The operation of the same parts as those of the first embodiment is common, and the description thereof will be omitted. The ambient light and the ambient light incident on the second signal input element 22 are held in the second signal level holding circuit 22, and the reflected light level held in the first signal level holding circuit 28 is held by the comparator 32. In comparison, the automatic deodorizer drive circuit 14 is driven. Thus, if the second signal incident element 22 is separately used as in the present embodiment, not only the human body and the ambient light and the ambient light can be detected at the same time, but the efficiency is increased, and the ambient light and the ambient light can be collected in real time. Therefore, it is possible to flexibly deal with the fluctuation of the light receiving level due to the transition of time, and the detection accuracy is further improved.

The first embodiment of the present invention shown in FIG. 2 will be described in more detail. Reference numeral 15 is a power supply for supplying a predetermined voltage to the entire circuit of the automatic deodorizer of the present invention, and various batteries and AC10
It is possible to use a dropper type power supply or the like, which is a 0V step-down rectifier. Reference numeral 11 denotes a modulation / demodulation circuit 11 that modulates the light emitted from the signal emitting element 19, and internally includes a modulator 16 and a demodulator 23. The modulator 16 is composed of an oscillator 17 and a frequency divider 18 which pass only the drive pulse and drive pulse of the signal emitting element 19 and generate a switching pulse of the analog switch in the subsequent stage and a reset pulse of the flip-flop. The oscillation frequency is adjustable.

A signal input / output circuit 12 comprises a signal output element 19, a signal input element 21, and an optical filter 20 provided in front of the signal input element 21. The signal emitting element 19 is an infrared LED element, the signal incident element 21 is highly sensitive,
Highly directional phototransistors are used, and optical filters are resin infrared light pass filters.

Reference numeral 13 denotes a human body presence / absence determining circuit, which includes a first analog switch 26, a second analog switch 27, and a first analog switch 2 for switching the output from the demodulator 23.
First signal level holding circuit 28 for holding the signal from 6
A second signal level holding circuit 31 that holds the signal from the second analog switch 27, a first signal level holding circuit 28, a comparator 32 that compares the signal levels of the second signal level holding circuit 31, and a comparator And a flip-flop 33 for temporarily storing the output from 32.

The first signal level holding circuit 28 holds the light receiving level when the signal emitting element 19 is active.
On the other hand, the second signal level holding circuit 31 includes the signal emitting element 19
Preserves ambient and ambient light levels when is inactive. In terms of circuitry, both are composed of an integrator circuit and a sample & hold circuit. The comparator 32 has a chattering prevention function corresponding to a minute fluctuation of the input having a hysteresis characteristic.

The flip-flop 33 is a comparator 3
Although the result of comparison in 2 is temporarily stored, this flip-flop 33 is provided to prevent a person from moving and stopping the absorption of the odor of the automatic deodorizer for a moment. The flip-flop 33 is a D-type flip-flop. Reference numeral 14 denotes an automatic deodorizer drive circuit, which is composed of a fan that drives the automatic deodorizer to adsorb odors, a power transistor that drives the fan, and a display LED 34 that indicates that the automatic deodorizer is being driven. Odor is adsorbed through activated carbon, and the material used is honeycomb-shaped activated carbon, which has a high adsorption capacity.

In the embodiment of the present invention, an AA alkaline battery is used as a power source, and the oscillation frequency of the oscillation circuit is sunlight (direct current), AC 100 V (50 Hz or 6 Hz).
Infrared light having a frequency higher than that which is likely to be erroneously detected, such as 0 Hz and its harmonics, for example, 1.83 KHz is selected. Further, the optical filter blocks visible light components of natural light such as sunlight and artificial light such as fluorescent lights, and allows only the infrared light components to pass through the signal incident element. By doing so, the possibility of false detection of the human body is reduced.

Next, the operation of the control circuit for the automatic deodorizer will be described based on the actual signal flow based on the block configuration of FIG. The operation of the circuit at the time of active emission of infrared light from the signal emitting element 19 will be mainly described. First, the signal emitting element 19 is driven by the oscillator 17 of the modulator 16 of the modulation / demodulation circuit 11, for example, 8.553825 μs (11
A drive pulse of 7.12 KHz) is generated, and this is divided by the frequency divider 18 into a predetermined clock width. This drive pulse becomes the reference timing clock that periodically operates the circuit. In the present invention, the active time is 5
The power consumption is reduced by setting it to less than 0%.
It is preferable that the duty cycle of the timing clock is variable.

When the light is emitted from the signal emitting element 19, the timing clock from the oscillator is supplied to the signal emitting element 19 so that the light is emitted from the signal emitting element 19. The emission angle is constant. When a person is near the automatic deodorizer, the signal incident element 21 detects light reflected by the human body, and when there is no person, reflected light from the periphery such as a wall near the automatic deodorizer is detected. The light reception level varies depending on the detection time and the lightness as well as the factors such as the position of the reflecting human body, the material of the clothes worn, the color, and the brightness.

When the signal emitting element 19 is inactive and does not emit light, the signal incident element 21 detects ambient light and disturbance light near the automatic deodorizer. The sampling period of the signal injection element 21 is determined by the clock generated by the oscillator. The light received by the signal incidence element 19 is amplified by the amplifier, removes unnecessary components by the filter, and enters the demodulator 23. The demodulator 23 captures the light reception signal in synchronization with the timing pulse generated by the oscillator 17 and the frequency divider 18.

(A) When active: The first analog switch 26 is turned on, the second analog switch 27 is turned off, and the received light is detected by the first human presence / absence determination circuit 13 as the first light.
It is input to the signal level holding circuit 28. (B) When inactive: The first analog switch 26 is turned off and the second analog switch 27 is turned on, and ambient light and disturbance light are input to the second signal level holding circuit 31.

The switching of the analog switch is performed by a timing pulse. When the timing pulse is L (low), the first analog switch 26 is turned on (off) and the second analog switch 27 is turned off ( On). When it is H (high), the opposite state occurs. First signal level holding circuit 28 and second signal level holding circuit 3
Since the operation of 1 is basically the same, it will be described collectively. The integrator circuit 29 and the sample-and-hold 30 are illustrated separately for convenience, but in reality they cannot be separated as one unit. The sample-and-hold circuit is a low noise J-FE
The T input type is used.

(C) Timing pulse is L: The sample-and-hold circuit is in the sample mode to form an integrator circuit, and charges (light reception level or disturbance light level) integrated in the time direction are stored in the hold capacitor. To charge. (D) Timing pulse is H: The sample & hold circuit is in the hold mode and outputs the electric charge charged from the hold capacitor.

The hold capacitor uses a film (polypropylene) capacitor having a low leakage current. As an example, the sample time is 34 μs, the hold time is 56 μs, and the acquisition time is 2 μs.
4 μs. The content of the signal level holding circuit is updated each time light is received by the signal incidence element 19. Further, in the flip-flop 33 at the next stage, the first signal level holding circuit 19 and the second signal level holding circuit 19
It is compared whether or not the value of the light receiving level held in the signal level holding circuit 31 is a certain value or more (150 mV (comparator comparison voltage hysteresis + margin voltage)). The threshold value that is used as a reference for determining the approach of the human body by the comparator 34 is not fixed as in the conventional case, and when inactive, when no light is emitted from the signal emitting element 19, a wall near the automatic deodorizer is provided. Since the reflected light from such as is incident on the signal incident element 19, the brightness of the wall and the brightness of the approaching human clothes are stored as the light receiving level when inactive, and a threshold value above a certain value is set as the threshold value. The possibility of malfunction due to changes in light and darkness of walls and human clothes can be significantly reduced. The comparison result is temporarily stored in the flip-flop 33. The flip-flop 33 is reset by a timing clock every fixed time. When the output difference compared with the comparator 32 is a certain value or more,
The deodorizer outputs a signal from the flip-flop 33 to the automatic deodorizer drive circuit 14, rotates the fan to adsorb the odor, and turns on the display LED 34 that indicates that the automatic deodorizer is in operation. When separated from, the deodorizer is operated for a while to complete the deodorizing effect of absorbing the odor, and then the fan is stopped and the display LED 34 is turned off. When the output difference is below a certain value, the automatic deodorizer drive circuit 1
Do not drive 4.

The control circuit for an automatic deodorizer according to the second embodiment of the present invention shown in FIG. 3 will be described in more detail. The difference from the first embodiment of FIG. 2 is that a signal injection element 22 dedicated to receiving ambient light and ambient light is provided independently. With this configuration, there is no need to switch between incident light and ambient light with an analog switch, as in the first embodiment. The operation of the circuit at the time of active emission of light from the signal emitting element 19 is the same as that of the first embodiment. The ambient light and the ambient light are sampled in synchronization with the operation of the signal emitting element 19. The reason why the signal incident element 21 dedicated to receiving ambient light and ambient light is separately provided is as follows. Not only can human body detection and ambient light and ambient light detection be performed at the same time to improve efficiency, but also ambient light and ambient light can be collected in real time, so fluctuations in the received light level over time can be flexibly dealt with, and detection efficiency can be improved. Also improves.

Although the above description mainly describes an example in which optical means is used, the technical idea of the present invention can be similarly applied to the case where ultrasonic waves are used as a medium. When ultrasonic waves are used, the modulation / demodulation circuit is not required as in the case of using light, so that the circuit configuration is somewhat simplified.

[0027]

As described in the above embodiments, according to the present invention, light is emitted from the signal emitting element 19 of the deodorizer and reflected by the approaching human body and detected by the signal incident element 21. It is possible to realize a control circuit with excellent detection accuracy for an automatic deodorizer that determines the presence or absence of a human body. (I) According to the first embodiment, the signal input / output circuit 12 and the modulation / demodulation circuit 16 recognize the intensity of disturbance such as reflected light from a wall near the automatic deodorizer to determine the presence or absence of a human body. By adding the determination circuit 13, it is possible to significantly reduce malfunctions caused by ambient light and ambient light due to changes in the brightness of walls and clothes near the automatic deodorizer, and it is possible to realize high reliability. The possibility of malfunctions is greatly reduced compared to the conventional one. In addition, the detection efficiency of the human body is significantly improved.

(Ii) According to the second embodiment, since another signal entrance element 22 is added to the circuit of the first embodiment, it is possible to detect the human body and the ambient light and the ambient light at the same time. Not only the efficiency is increased, but also ambient light and ambient light can be collected in real time, so that it is possible to flexibly deal with the fluctuation of the received light level due to the transition of time, and the detection efficiency is also improved.

[Brief description of the drawings]

FIG. 1 is a diagram showing a principle configuration of a control circuit for an automatic deodorizer according to the present invention, wherein (A) uses light as a medium and (B) uses ultrasonic waves as a medium.

FIG. 2 is a block diagram showing a first embodiment of a control circuit for an automatic deodorizer according to the present invention.

FIG. 3 is a block diagram showing a second embodiment of a control circuit for an automatic deodorizer according to the present invention.

FIG. 4 is a block diagram showing a conventional control circuit for an automatic deodorizer.

[Explanation of symbols]

 1, 5 ... Human body detection means 2 ... Ambient light detection means 3 ... Comparison means 4 ... Driving means 6 ... Disturbance sound detection means 11 ... Modulation / demodulation circuit 12 ... Signal input / output circuit 13 ... Human body presence / absence determination circuit 14 ... Automatic deodorizer Drive circuit 16 ... Modulator 17 ... Oscillator 18 ... Frequency divider 19 ... Signal emitting element 20 ... Optical filter 21 ... Signal incident element 22 ... Second signal incident element 23 ... Demodulator 26 ... First analog switch 27 ... Second Analog switch 28 ... First signal level holding circuit 31 ... Second signal level holding circuit 34 ... Comparator 36 ... Display LED

Claims (15)

[Claims] 1. A control circuit for an automatic deodorizer for automatically controlling deodorization by detecting the presence or absence of an approaching human body, a human body detecting means (1) for detecting an approaching human body, and ambient light or ambient light. Ambient light detecting means (2) for detecting the following, a comparing means (3) for comparing the respective signal levels respectively detected by the human body detecting means (1) and the ambient light detecting means (2), and the comparing means ( A control circuit for an automatic deodorizer, comprising: a drive means (4) for driving the automatic deodorizer according to the comparison result of 3). 2. The comparing means (3) comprises a first signal level holding circuit (28) for holding the level of reflected light from the human body and a second signal level holding circuit (31) for holding the levels of ambient light and disturbance light. ), A comparator (32) for comparing respective outputs from the first signal level holding circuit (28) and the second signal level holding circuit (31), and a flip-flop for storing a comparison result of the comparator (32). (33) and a human body presence / absence determination circuit (1
The control circuit for an automatic deodorizer according to claim 1, which is constituted by 3). 3. The human body detecting means (1) comprises a modulation / demodulation circuit (11) and a signal input / output circuit (12) driven by a pulse generated in the modulation / demodulation circuit (11). The control circuit for an automatic deodorizer according to Item 1. 4. The modulator / demodulator circuit (11) includes a modulator (16) including an oscillator (17) and a frequency divider (18) for dividing a clock from the oscillator (17), and the frequency divider. The automatic deodorizer control circuit according to claim 3, comprising a demodulator (16) that demodulates the modulated light in synchronization with the timing pulse generated from (18). 5. The signal input / output circuit (12), which is driven by the drive clock from the modulator (16), outputs a light for detecting the presence or absence of a human body, and a signal output element (19). A signal incident element (21) for injecting and detecting a signal emitted from the signal emitting element (19), and a signal incident element (21) provided in front of the signal incident element (21) to block visible light components and only infrared light components. Optical filter (2
0) and the control circuit for an automatic deodorizer according to claim 3. 6. The signal input / output circuit (12), a signal output element (19) for outputting a signal by driving with a drive clock from the modulator (16), and the signal output element (19). A first signal entrance element (21) for detecting a signal emitted from the first signal entrance element and a second signal entrance element (22) arranged in the vicinity of the first signal entrance element (21) for detecting ambient light or disturbance light. The control circuit for an automatic deodorizer according to claim 3, which is composed of 7. The automatic deodorizer according to claim 1, wherein the drive means (4) is composed of an automatic deodorizer drive circuit (14) that receives a signal from the flip-flop (33) and absorbs an odor. Dexterous control circuit. 8. The automatic deodorizer drive circuit (14) further comprises a display LED (34) which is turned on when the automatic deodorizer drive circuit (14) starts operating and is turned off when the operation is stopped. The control circuit for an automatic deodorizer according to claim 7. 9. The ambient light detecting means according to claim 1, wherein the ambient light detecting means (2) comprises a second signal entrance element (22) for detecting ambient light and ambient light. 10. The second signal emitting element (22) detects ambient light or disturbance light in synchronization with the emission from the signal emitting element 8 (22), and detects the ambient light or ambient light. The automatic deodorizer control circuit according to claim 8, wherein the control circuit is sent to (31). 11. The first signal level holding circuit (28)
The second signal level holding circuit (31) detects and holds the signal emitted from the signal emitting element (19) by the signal incident element (21) when the signal emitting element (19) is active. Holds the ambient light level and the ambient light level incident on the signal input element (21) when the signal output element (19) is inactive, and the comparator (32) holds the first signal level holding circuit (28). ) And the signal level of the second signal level holding circuit (31) are compared with each other to determine whether the difference in output is a certain value or more, and when the difference is more than a certain value, the signal is sent to the automatic deodorizer drive circuit (14). The control circuit for an automatic deodorizer according to claim 2. 12. In the human body presence / absence determination circuit (13), when the signal emitting element (19) is active, the first
The analog switch (26) is turned on and the second analog
The switch (27) is turned off, and the signal emitting element (1
The signal emitted from 9) is detected by the signal incident element (21) and held by the first signal level holding circuit (28),
Further, when the signal emitting element (19) is inactive, the first analog switch (26) is turned off and the second analog switch (27) is turned on so that the signal is incident on the signal incident element (21). The control circuit for an automatic deodorizer according to claim 2, wherein the levels of the ambient light and the ambient light are held by the second signal level holding circuit (31). 13. The modulator / demodulator circuit (11), wherein the modulator (16) modulates at a frequency that can be discriminated from artificial light, and the pulse thereof has a predetermined duty cycle. (23) is the signal emitting element (19)
4. When is active, the reflected light emitted from the signal emitting element (19) and reflected by the human body is demodulated.
Control circuit for automatic deodorizer described in. 14. In the human body presence / absence determination circuit (13), the threshold value of the comparator (32) is not fixed, and the second signal level holding circuit (when the signal emitting element (19) is inactive. 11. The automatic operation according to claim 10, wherein the ambient light or the brightness of an approaching human body is stored in 31) as a light reception level, and the threshold value is a value greater than a certain value than that value, so that malfunction due to ambient light or ambient light can be significantly reduced. Control circuit for deodorizer. 15. A human body detecting means (5) for detecting an approaching human body using ultrasonic waves as a medium in an automatic deodorizer control circuit for automatically controlling the deodorizer by detecting the presence or absence of an approaching human body. A disturbance sound detecting means (6) for detecting a disturbance sound, a comparing means (3) for comparing the human body detecting means (5) and the signal level detected by the disturbance sound detecting means (6), and the comparing means ( A control circuit for an automatic deodorizer, comprising: a drive means (4) for driving the automatic deodorizer according to the result of 3).