JP2815274B2 - 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 device, 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. Then, when there is any object such as a human body in the space where the infrared light is projected, the projection light 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.

For this reason, when the wavelength of the disturbance light matches the wavelength of the light projected from the light emitting element, especially in the case of periodic pulse noise, whether an object actually exists or disturbance light is generated. That is, it cannot be determined whether or not the object is detected, and an accurate object detection cannot be performed.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to accurately detect an object even when disturbance light such as periodic pulse noise or periodic pulse noise is generated. It is an object of the present invention to provide an object detection device capable of performing the following.

[0009]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention detects an object by projecting light from a light-emitting element and detecting, by a light-receiving element, light reflected by the projected light hitting the object. In such an object detection device, the light-emitting element does not emit light for a certain period of time, the light-generating pattern detected by the light-receiving element at that time is learned, and then the light-emitting element is adjusted so as not to match the learned light-generating pattern. When the light receiving element receives the reflected light with respect to the light emission of the light emitting element, it is determined that an object exists, and when the light receiving element does not receive the reflected light, the object does not exist. The gist is that a control determination device for determining is made.

[0010]

The light detected by the light-receiving element when the light-emitting element is not emitting light is not reflected light of the light projected from the light-emitting element hitting the object, but is disturbance light generated for some reason.

Therefore, the control determination device learns the light detected by the light receiving element, that is, the pattern of occurrence of disturbance light. Next, the control determination device causes the light emitting element to emit light so as not to match the learned disturbance light generation pattern. As a result, the disturbance light does not coincide with the light emission of the light emitting element.

The control determining device determines that an object is present when the light receiving element receives the reflected light from the light emitting element. In addition, the control determination device,
When the light receiving element does not receive the reflected light from the light emitting element, it is determined that the object is not present.

[0013] Thus, the light received by the light receiving element is not necessarily due to disturbance light, but is always due to the reflected light of the light emitted from the light emitting element reflected on the object. Therefore, an object can be accurately detected without being affected by disturbance light.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment in which the object detecting apparatus of the present invention is embodied in an automatic washing apparatus for a flush toilet for men (hereinafter referred to as 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 projects 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 according to the present 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 switching 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 an output timing of a light emission signal F described later, a result of a human detection operation, and the like, an input / output interface,
And so on.

The microcomputer 22 starts operating when the switch SW is turned on by the installer of the automatic cleaning apparatus, and stops operating when the switch SW is turned off. That is, when the switch SW is turned on, the microcomputer 22
First, as described later, the output timing of the light emission signal F is set. Subsequently, the microcomputer 22 outputs the light emission signal F and the command signal S three times at predetermined time intervals based on the set output timing of the light emission signal F, and performs a human detection operation as described later.

The light emission drive circuit 23 causes the light emitting element 6a to emit light based on the light emission signal F from the microcomputer 22. The switching circuit 24 is turned on / off based on a command signal S from the microcomputer 22. The switching circuit 24 supplies the power supplied from the constant voltage circuit 20 to the light receiving circuit 25 when turned on, and shuts off the power supply to the light receiving circuit 25 when turned off. The light receiving circuit 25 becomes operable only when power is supplied from the switching circuit 24.

The light receiving circuit 25 amplifies the detection signal of the light receiving element 6b and outputs it as a light receiving signal R to the microcomputer 22. That is, when a person is standing in front of the morning glory 1, the light emitting element 6
The projection light from a is reflected by the person. Then
The light receiving element 6b detects the reflected light and outputs a detection signal, and the light receiving circuit 25 amplifies and outputs the detection signal.
On the other hand, when no person stands in front of the morning glory 1,
The projection light from a 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 25 does not output the light receiving signal R.

The light receiving element 6b outputs a detection signal in the same manner whether the reflected light of the light projected from the light emitting element 6a is received or the disturbance light having the same wavelength as the light projected by the light emitting element 6a. I do. Therefore, the light receiving circuit 25 similarly receives the light receiving signal R regardless of whether the light receiving element 6b receives the reflected light of the light projected from the light emitting element 6a or the disturbance light having the same wavelength as the light projected on the light emitting element 6a. 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, the setting of the output timing of the light emission signal F by the microcomputer 22 will be described with reference to FIG.
When the switch SW is turned on, the microcomputer 22 outputs a command signal S to the switching circuit 24 for a fixed time to enable the light receiving circuit 25. At this time, the microcomputer 22
Does not output the light emission signal F to the light emission drive circuit 23 and does not cause the light emitting element 6a to emit light. Therefore, the light receiving element 6b cannot receive the reflected light of the projection light of the light emitting element 6a, and when no disturbance light is generated, the light receiving circuit 25 outputs the light receiving signal R.
Is not output. Then, the microcomputer 22 sets the switch SW
The output timing of the light emission signal F is set to a fixed time (hereinafter, referred to as a light emission timing setting time) during which the command signal S is output from the input of the input signal to enable the light receiving circuit 25 to operate.

That is, for example, when disturbance light (periodic pulse noise) having a period T as shown in FIG. 4 is generated, the light receiving element 6b receives the disturbance light during the light emission timing setting time and receives the disturbance light. The circuit 25 outputs a light receiving signal R. Therefore, the microcomputer 22 detects the period T of the disturbance light by detecting the period of the light receiving signal R. Then, the microcomputer 22 calculates a period τ of the light emission signal F that does not match the disturbance light, and sets the output timing of the light emission signal F based on the period τ.

Also, when the disturbance light whose period changes in a constant pattern (periodic change pulse-like noise) is generated, similarly to the case where the periodic disturbance light is generated, the light receiving element 6b Receives the disturbance light, and the light receiving circuit 25 outputs a light receiving signal R. Therefore, the microcomputer 22 learns the pattern of the change of the period of the disturbance light, that is, the generation pattern during the light emission timing setting time, and calculates the output timing of the light emission signal F that does not match the generation pattern of the disturbance light. Set.

Then, based on the set output timing of the light emission signal F, the microcomputer 22 outputs the disturbance light and the light emitting element 6.
The light emission signal F is output three times so that the light emission of a does not match. Further, the microcomputer 22 outputs the command signal S three times corresponding to the light emission signal F, as shown in FIG.

As a result, the light receiving circuit 25 becomes operable only when the light emitting element 6a emits light, and the light receiving element 6b
Receives only the reflected light of the projection light of the light emitting element 6a, not the disturbance light. Therefore, the light receiving signal R output from the light receiving circuit 25 is not necessarily based on disturbance light, but is always based on reflected light of the projected light of the light emitting element 6a.

Thereafter, the microcomputer 22 outputs the light emission signal F and the command signal S three times at predetermined time intervals based on the set output timing of the light emission signal F.
Therefore, the light emitting element 6a emits light three times every predetermined time.

Next, the human detection operation of the microcomputer 22 will be described. The light receiving element 6b can receive light only when a person stands before the morning glory 1 with respect to the light emission of the light emitting element 6a, and the light receiving circuit 25 outputs the light receiving signal R.
Therefore, if a person stands in front of the morning glory 1 with respect to three times of light emission of the light emitting element 6a based on the set output timing of the light emitting signal F, the light receiving element 6b detects the reflected light of each time, The light receiving circuit 25 outputs the light receiving signal R three times.

However, when a person does not stand in front of the morning glory 1 but simply crosses in front of the morning glory 1, the light receiving element 6b receives the light emitted from the light emitting element 6a three times. Not all reflected light can be detected each time. That is, the light receiving element 6b can receive light only once or twice for three times of light emission of the light emitting element 6a. Therefore, the light receiving circuit 25 can output the light receiving signal R only once or twice.

Therefore, the microcomputer 22 determines that the light receiving element 6b can receive all three times of the light emission of the light emitting element 6a three times (that is, the light receiving signal R from the light receiving circuit 25 becomes three).
Only when the output is performed twice), it is determined that a person is standing in front of the morning glory 1 and “human detection” is determined.

That is, the microcomputer 22 determines that the light receiving element 6b cannot receive light even once for three times of light emission of the light emitting element 6a (that is, the light receiving signal R from the light receiving circuit 25 becomes 1).
Is output only once or twice), it is determined that no person is standing in front of the morning glory 1 and “human non-detection” is determined.

The microcomputer 22 performs the "human detection"
Alternatively, the determination result of “non-detection of person” is stored in the RAM. A series of operations of the microcomputer 22 is a human detection operation, and is repeatedly performed every time the light emitting element 6a emits light three times, and each time a determination result of “human detection” or “non-human detection” is stored in the RAM. Is stored.

Then, as shown in FIG.
If the determination result of “human detection” continues twice after the determination result of “”, the microcomputer 22 determines that the person standing in front of the morning glory 1 is going to add a small business.

This is because even if a person crosses in front of the morning glory 1, a determination result of "human detection" may occur only once. That is, if the determination result of “human detection” is repeated twice, the person standing in front of the morning glory 1 has been stopped for a predetermined time or more. You are trying to add

Then, the microcomputer 22 controls the valve drive circuit 21 to open the electromagnetic on-off 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.
Wash 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, as shown in FIG. 6, when the determination result of “human detection” is followed by the determination result of “non-human detection” twice, the microcomputer 22 determines that the person who has finished using the small work is a morning glory. It is determined that the person has left before 1.

This is because even if the body of the person shakes during the small use, a determination result of "non-detection of the person" may occur only once. In other words, if the result of the determination of "person not detected" is repeated twice, there is no person for more than a predetermined time in front of the morning glory 1, and it can be surely confirmed that the person who has completed the small-work has left. is there.

Then, the microcomputer 22 controls the valve drive circuit 21 to open the electromagnetic on-off 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.
Wash morning glory 1.

As described above, in the apparatus for automatically cleaning morning glory 1, when a person who wants to add a small product 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.

As described in detail above, in this embodiment, the pattern of occurrence of disturbance light is detected by detecting the light receiving state of the light receiving element 6b without causing the light emitting element 6a to emit light for a certain time after the switch SW is turned on. doing.

The light emission timing of the light emitting element 6a is set by setting the output timing of the light emission signal F so as not to coincide with the disturbance light generation pattern. Therefore, even when disturbance light such as periodic pulse-like noise or period-change pulse-like noise is generated, the light-emitting element 6a is caused to emit light so as not to match the disturbance light. Can accurately detect whether or not a person is standing in front of it.

The present invention is not limited to the above embodiment, but may be carried out as follows. 1) The light emission timing setting time is provided at every certain time during the operation of the microcomputer 22 instead of setting a certain time from the turning on of the switch SW as the light emission timing setting time.
Then, the output timing of the light emission signal F is changed for each light emission timing set time provided for each fixed time.

In this case, even if the period of the disturbance light changes,
Since the output timing of the light emission signal F can be made to correspond to the change in the period of the disturbance light, it becomes more effective against the period-changed pulse-like noise.

2) In the cycle of the human detection operation, the remaining time when the light emitting element 6a emits light three times is set as the light emission timing setting time. In this case, the output timing of the light emission signal F can be changed for each cycle of the human detection operation.
Even if the period of the disturbance light frequently changes in a short time, the output timing of the light emission signal F can be made to correspond to the change of the period of the disturbance light. Therefore, it is extremely effective against period-change pulse noise.

3) The period of the human detection operation is set to an appropriate time, not a fixed time. 4) The number of light emission of the light emitting element 6a in one human detection operation is set to an appropriate number instead of three. In that case,
The number of times of the command signal S is not three, but according to the number of times of light emission of the light emitting element 6a.

5) The light emission timing setting time is set to an appropriate time instead of one second. If the light emission timing setting time is made longer, it is possible to detect the occurrence pattern of disturbance light more accurately.

6) In the light emission timing setting time, instead of receiving the disturbance light by the light receiving element 6b of the human detection sensor 6, a dedicated light receiving element for receiving the disturbance light is provided. The microcomputer 22 sets the output timing of the light emission signal F based on a detection signal of a light-receiving element dedicated to disturbance light provided separately from the light-receiving element 6b.

7) The pre-cleaning process is performed even if the determination result of "human detection" is found only once after the determination result of "human detection". The post-cleaning process is performed even when the determination result of “human detection” is once after the determination result of “human detection”.

8) The light emission signal F is a plurality of pulses having an appropriate duty different from the frequency of the pulse noise and an arbitrary duty. 9) Replace the lithium battery 8 with a DC power supply and supply power from a commercial power supply.

10) 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 projection light and outputs a detection signal.

11) Use ultrasonic waves instead of light. That is, the light emitting element 6a is replaced with an ultrasonic speaker,
The light receiving element 6b is replaced with an ultrasonic microphone.
Further, the circuit configurations of the light receiving circuit 25 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.

12) The present invention is embodied not only in the morning glory 1 but also in an automatic washing control device for various sanitary appliances such as a sink. 13) Not only automatic cleaning control device in sanitary ware,
The present invention is embodied in other object detection devices such as automatic doors and FA devices.

14) The above-mentioned 1) to 13) are carried out in an appropriate combination.

[0058]

As described above in detail, according to the present invention, an excellent effect that an object can be accurately detected even when disturbance light such as periodic pulse noise or periodic pulse noise is generated. is there.

[Brief description of the drawings]

FIG. 1 is an electric block circuit diagram of an automatic cleaning device according to one embodiment of the present invention.

FIG. 2 is a partially cutaway side view showing an attached state of a flush toilet for men according to one embodiment.

FIG. 3 is a front view of the flush urinal for men shown in FIG. 2;

FIG. 4 is a time chart for explaining setting of an output timing of a light emission signal F in one embodiment.

FIG. 5 is a time chart for explaining a pre-cleaning process in one embodiment.

FIG. 6 is a time chart for explaining a post-cleaning process in one embodiment.

[Explanation of symbols]

6a: light-emitting element, 6b: light-receiving element, 22: microcomputer as control determination device

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G01V 9/04 E03D 5/10

Claims (1)

(57) [Claims] A light is projected from a light emitting element (6a), and reflected light reflected by the projected light hitting an object is received by a light receiving element (6a).
In the object detection device configured to detect an object by performing the detection in step b), the light emitting element (6a) is not caused to emit light for a certain period of time, and the light generation pattern detected by the light receiving element (6b) at that time is learned. Next, the light emitting element (6a) emits light so as not to match the learned light generation pattern, and the light emitting element (6a)
It is determined that an object is present when the light receiving element (6b) receives the reflected light with respect to the light emission of, and the object is not present when the light receiving element (6b) does not receive the reflected light. An object detection device, comprising: a control determination device (22) for determining whether the object is detected.