JPH06242256A - Human body detector - Google Patents

Abstract

PURPOSE:To provide a human body detector capable of extending the life of a sensor and preventing the erroneous operation due to a neighboring heat source. CONSTITUTION:A human body detector has a pyroelectric sensor 4 detecting the presence of the human body moving within a first predetermined detection area, the distance measuring sensor 5 provided in the first detection area and detecting the presence of the human body stationary in a second detection area narrower than the first detection area and and a control circuit 3 setting the distance measuring sensor 5 to an operative state by the detection output of the pyroelectric sensor and setting the distance measuring sensor 5 to an operation stop state after a predetermined time when the pyroelectric sensor 4 is in an undetected state and the output of the distance measuring sensor 5 changes from a detection state to a non-detection state and setting the period of the predetermined time to the period detecting the presence of the human body to detect the presence of the human body on the basis of the detection outputs of both of the pyroelectric sensor 4 and the distance measuring sensor 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a human body detecting device for detecting the presence of a human body.

[0002]

2. Description of the Related Art Some human body detecting devices detect the presence of a human body by utilizing radiant heat from the human body. In this device, radiant heat from the human body is received by the thermopile used as a sensor. Then, this device detects the presence of a human body based on the detection output from the thermopile.
Such a human body detection device is described in Japanese Patent Laid-Open No. 64-65888.

Some human body detection devices use a light emitting element and a light receiving element as a sensor for detecting the presence of a human body. Then, this device makes the light from the light emitting element into a slit (band) shape, and emits the slit-shaped beam light. The reflected light of this beam light is received by a plurality of light receiving elements,
The presence of a human body is detected based on the change in the current from each light receiving element. Such a human body detecting apparatus is disclosed in Japanese Patent Laid-Open No. 2-126.
719.

By using these human body detection devices, the presence of a moving human body or a stationary human body can be detected.

[0005]

By the way, in a human body detecting device using a thermopile, if there is a heat source such as a heating device in the vicinity of this device, this heat causes a human body to be detected and malfunctions occur.

Further, in the human body detecting device using the slit-shaped beam light, the optical system of the light projecting means for emitting this light and the condensing means for condensing the slit-shaped reflected light becomes complicated, and the production cost is increased. Invite. Further, in this device, the light emitting element of the sensor always emits light, so that the life of the light emitting element is shortened.

An object of the present invention is to eliminate the above drawbacks and to provide a human body detecting device which can extend the life of the sensor and prevent malfunction due to a nearby heat source.

[0008]

In order to achieve the object, the present invention provides a passive sensor for detecting the presence of a human body moving in a predetermined first detection area, and a passive sensor in the first detection area. , An active sensor that detects the presence of a human body that is stationary in a second detection area that is narrower than the first detection area, and an active sensor that is activated by the detection output of a passive sensor, and the passive sensor is in an undetected active state When the output of the sensor changes from the detection state to the non-detection state, the active sensor is deactivated after a predetermined time and the presence of the human body is detected for a predetermined time, so that the passive sensor and the active sensor are detected. And a control means for detecting the presence of a human body based on the detection output.

Further, according to the present invention, a passive sensor for detecting the presence of a human body moving in a predetermined first detection area, and a second detection area within the first detection area and narrower than the first detection area The active sensor that detects the presence of a stationary human body and the detection output of the passive sensor activates the active sensor, and when the output of the active sensor is in the non-detection state, the active sensor is deactivated after a predetermined time. And a control means for detecting the presence of the human body based on the detection outputs of the passive type sensor and the active type sensor by detecting the presence of the human body for a predetermined time during the state.

In the present invention, the passive sensor is a pyroelectric sensor that detects the presence of a human body based on infrared rays from the human body.

Further, in the present invention, the active sensor is
It is a distance measuring sensor that detects the presence of a human body based on a change in the measured distance.

[0012]

According to the present invention, a person enters the first detection area,
When moving in the first detection area, the passive sensor detects the presence of this moving human body. Upon receiving this detection result, the control means starts the operation of the active sensor. After this,
When a person enters the second detection area and stands still, the active sensor detects the presence of this standing human body.

At this time, even if the active sensor changes to a state where it does not detect a human body, that is, a non-detection state, the control means still operates.
Instead of immediately deactivating the active sensor, the active sensor is deactivated after a lapse of a predetermined time. After the passive sensor detects the presence of the human body, if the active sensor is in the non-detection state, the control means does not immediately deactivate the active sensor but deactivates it after a lapse of a predetermined time.

Further, by using the pyroelectric sensor as the passive sensor, the presence of the moving human body is detected based on the infrared rays generated by the human body when the human body is moving.

Further, by using the distance measuring sensor as the active sensor, when the human body is stationary, the presence of the stationary human body is detected based on the change in the measured distance.

[0016]

Embodiments of the present invention will now be described with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the present invention. The human body detection device according to this embodiment includes a power supply circuit 1
A drive circuit 2, a control circuit 3 as a control unit, a pyroelectric sensor 4 as a passive sensor, a distance measuring sensor 5 as an active sensor, and timers 6 and 7.

The power supply circuit 1 of the human body detecting device generates a DC voltage from the AC voltage of the commercial power supply 11 and supplies the DC voltage to each circuit. Further, the power supply circuit 1 supplies an AC voltage from the commercial power supply 11 to the drive circuit 2.

The drive circuit 2 supplies the AC voltage of the power supply circuit 1 to the load 12 by the control output from the control circuit 3.
That is, the drive circuit 2 operates like a switch that turns on and off the AC voltage from the power supply circuit 1 with respect to the load 12.

The pyroelectric sensor 4 has a pyroelectric element (not shown). The pyroelectric element is polarized in a steady state and maintains electrical neutrality due to the attachment of electric charges in the air. In this state, when the pyroelectric element absorbs far infrared rays generated by the human body, the temperature of the pyroelectric element rises and the polarization state changes. Due to this change, the pyroelectric element releases the attached charge, so that a current is temporarily generated. The pyroelectric sensor 4 detects the presence of a human body by the electric current generated by the pyroelectric element. However, when the pyroelectric element releases the charge, the attached charge matches the polarization, and no current is generated. As a result, the pyroelectric sensor 4 detects only the presence of a moving human body.

Further, since the pyroelectric sensor 4 detects the presence of the human body by far infrared rays generated by the human body, it can detect the presence of the human body over a wide range. That is, as shown in FIG. 2, the detection area 21 of the pyroelectric sensor 4 becomes wider.
However, since the pyroelectric sensor 4 uses a multi-divided lens (not shown) or a mirror (not shown) to efficiently collect far infrared rays from the human body, The part that detects the human body becomes rough. Moreover, the presence of a human body of a certain size or larger and the presence of a human body moving at a certain speed or more are detected.

The distance measuring sensor 5 is an infrared emitting LED (Ligh
t Emitting Diode) and PSD (Position Sensitive D)
evice) and. In addition, infrared emitting LED and P
SD is not shown in FIG. The distance measuring sensor 5 is
When the PSD receives infrared reflected light from the infrared emitting LED, the distance between the sensor and the reflection position is measured from the positional deviation of the reflected light. That is, the distance measuring sensor 5 is
The distance when the person does not exist is compared with the distance when the person exists, and the presence of the human body is detected based on the change of the distance information. Therefore, since the distance measuring sensor 5 utilizes reflection of infrared light, the distance measuring sensor 5 can detect the distance only in a narrow range. That is, as shown in FIG. 2, the detection area 22 of the distance measuring sensor 5 is narrower than that of the pyroelectric sensor 4.

Such an operation of the distance measuring sensor 5 is controlled by a control output from the control circuit 3. That is, when the distance measuring sensor 5 receives the control output of "H (high)" from the control circuit 3, it emits infrared rays from the infrared ray emitting LED to be in an operating state capable of detecting the presence of a human body, When the control output is "L", the operation is stopped.

The timers 6 and 7 are time measuring devices. The timer 6 detects when the pyroelectric sensor 4 first detects the presence of a human body, and when the distance measuring sensor 5 performs the next detection in a non-detection state,
It is reset and started under the control of the control circuit 3.
Then, the timer 6 has timed out after a predetermined time, and notifies the control circuit 3 of the timed up. The timer 7 is reset and started under the control of the control circuit 3 when the distance measuring sensor 5 does not detect the presence of the human body after the pyroelectric sensor 4 first detects the presence of the human body. And after a certain amount of time, it will be up,
Notify the control circuit 3 that the time is up.

The control circuit 3 controls the pyroelectric sensor 4 and the distance measuring sensor 5. Further, the control circuit 3 detects the presence of a human body from the pyroelectric sensor output from the pyroelectric sensor 4 and the distance measuring sensor output from the distance measuring sensor 5, generates a control output, and outputs the control output. To the drive circuit 2. Further, the control circuit 3 always operates the pyroelectric sensor 4, and when the pyroelectric sensor 4 detects the presence of a human body, controls the distance measuring sensor 5 to operate. Further, the control circuit 3 includes timers 6, 7
Is operating, the control output is kept at "H", and when the timers 6 and 7 are timed out, a control output of "L" is sent to the distance measuring sensor 5, and the distance measuring sensor 5 is deactivated. To do.

Next, the operation of this embodiment will be described by taking as an example the case of turning on and off the illumination of the toilet using this embodiment. Here, as shown in FIG. 3, the human body detection device is attached to the ceiling 30 of the toilet and above the toilet bowl 31 of the toilet. Further, the lighting fixture 32 is used as the load 12.

When the human body detection device is attached to the toilet, the detection area 21 of the pyroelectric sensor 4 of the human body detection device
Covers the entire toilet. Further, the detection area 22 of the distance measuring sensor 5 is around the toilet bowl 31. Then, under the control of the control circuit 3, only the pyroelectric sensor 4 is operating.

In such a case, when the person 101 tries to use the toilet, the processes shown in FIGS. 4 and 5 are performed. That is, as shown in FIG. 6, when the person 101 opens the toilet door 30A at the time T1 and enters the inside, the pyroelectric sensor 4 detects the presence of the person 101 (step S1),
The output of “H” is sent to the control circuit 3. Note that step S1
When the pyroelectric sensor 4 does not detect the presence of a human body, the processing returns to the original.

The control circuit 3 sends the output of "H" to the drive circuit 2 and the distance measuring sensor 5 by the output of the pyroelectric sensor. This control output causes the distance measuring sensor 5 to start operating (step S2). At the same time, this control output causes the drive circuit 2 to turn on the lighting fixture 32.

When the person 101 enters the detection area 22 of the distance measuring sensor 5 at time T2, the distance measuring sensor 5 generates an output of "H" and sends it to the control circuit 3 (step S3). After this, at time T3, the person 101 stops in front of the toilet bowl 31 or the toilet bowl 3
When a person sits down on 1, the pyroelectric sensor 4 stands still 101
Is not detected, the output of the pyroelectric sensor 4 becomes "L". However, the output of the distance measuring sensor of "H" has already been output from the control circuit 3.
, The control circuit 3 continues to send the output of “H” to the drive circuit 2. With this control output, the drive circuit 2 causes the lighting fixture 32 to continue lighting.

Time T4 for person 101 to leave the toilet
, The pyroelectric sensor 4 outputs “H” output to the control circuit 3
Send to. Then, when the person 101 goes out of the detection area 22 of the distance measuring sensor 5 at time T5, the distance measuring sensor 5 sends the output of “L” to the control circuit 3. That is, the process in step S3 becomes “NO”. Then, the control circuit 3 uses the timer 7
Are reset and started (step S4). However, at this time, since the output of the pyroelectric sensor of "H" is added to the control circuit 3 (step S5), the control circuit 3 continues to send the output of "H" to the drive circuit 2 and
Reset and start the timer 6 (step S
6). At this time, since the output of the distance measuring sensor 5 is "L", the process in step S7 is "NO". When the distance measuring sensor 5 detects the presence of a human body in step S7, the process returns to step S3.

When the person 101 leaves the toilet at time T6,
Since it is outside the detection area 21 of the pyroelectric sensor 4, the pyroelectric sensor 4 sends an output of "L" to the control circuit 3 (step S8). That is, the process in step S8 becomes "NO". After the processing of step S8, when the timer 6 times up at time T7 (step S9), the control circuit 3
The control output of "L" is generated. Due to this control output, the operation of the distance measuring sensor 5 is stopped, and the drive circuit 2 causes the lighting fixture 32.
Is turned off (step S10).

As a result, when the person 101 is in the toilet, the lighting device 32 is automatically turned on and the inside of the toilet can be kept bright.

By the way, as shown in FIG.
There is a case where 01 is not detected by the distance measurement sensor 5 and the person 101 leaves the toilet or the person 101 stands still in the detection area 21 of the pyroelectric sensor 4 as shown in FIG. 7B. At this time, as shown in FIG. 8, the output of the distance measuring sensor 5 is in the state of "L" even after the output of the pyroelectric sensor 4 is set to "L" at time T3. That is, the process in step S3 becomes "NO", the timer 7 starts in step S4, the process in step S5 becomes "NO", and the process in step S11 becomes "NO".

Since the timer 7 is operating during this period, the control circuit 3 sends the control output of "H" to the drive circuit 2 even if the outputs of the pyroelectric type sensor 4 and the distance measuring sensor 5 are "L". As a result, the luminaire 32 continues to light.

When the timer 7 times out (step S12), the control circuit 3 generates a control output of "L". As a result, the operation of the distance measuring sensor 5 is stopped and the lighting fixture 32 is turned off. In step S12, the timer 7
Is operating, the process returns to step S5.

As a result, even if the output as shown in FIG. 8 is generated, as shown in FIGS. 7 (a) and 7 (b), the person 101 may be in the toilet, so It will not be erased immediately.

Further, as shown in FIG. 9, the person 101 sitting on the toilet bowl 31 may move his / her body and get out of the detection area 22 of the distance measuring sensor 5. At this time, as shown in FIG. 10, the output of the distance measuring sensor 5 becomes "L" between the time T8 and the time T9. That is, after the processing in step S3 becomes "NO", the timer 7 starts in step S4, the processing in step S5 becomes "NO", and further the processing in step S11 becomes "YES". At this time, the process returns to step S3. During this time, since the timer 7 is operating, the control circuit 3 generates the control output of "H", and the lighting fixture 32 continues to light.

As a result, when the person 101 is in the toilet, even if the outputs of the pyroelectric type sensor 4 and the distance measuring sensor 5 temporarily become "L", the lighting fixture 32 continues to light.

As described above, in this embodiment, the pyroelectric sensor 4 and the distance measuring sensor 5 are used, and the timers 6 and 7 are used. Therefore, even if the person 101 takes an unusual action in the toilet, It is possible to prevent the lighting fixture 32 from being immediately turned off. In particular, if the predetermined time of the timer 7 is lengthened, the presence of a human body can be reliably detected when a person is in the toilet and the outputs shown in FIGS.

When the person 101 is in the toilet, the lighting device 32 is automatically turned on to keep the inside of the toilet bright. At this time, since the distance measuring sensor 5 operates after the pyroelectric sensor 4 detects the person 101, the life of the infrared emitting LED of the distance measuring sensor 5 can be extended and the power consumption can be suppressed. .

Further, since the pyroelectric type sensor 4 and the distance measuring sensor 5 are selectively used, it can be surely detected whether or not the person 101 is in the toilet.

Although the distance measuring sensor 5 is used as the active sensor in this embodiment, the active sensor is not limited to this, and may be an active sensor using a photodiode or a phototransistor instead of the PSD, for example. At this time, the presence of reflected light is checked to detect the presence of a human body.

Further, an active sensor using ultrasonic waves may be used instead of the infrared reflective active sensor. At this time, the presence of a reflected wave may be checked to detect the presence of the human body, or the distance may be checked from the reflection time.

Further, in the operation of this embodiment, the load 12
Although the lighting equipment for the toilet is used as, the invention is not limited to the toilet and the lighting equipment. For example, a ventilation fan, an air conditioner, various alarm devices, etc. may be used as the load 12.

[0046]

As described above, according to the present invention, when the passive sensor changes from the detection state to the non-detection state due to the action of a person, even if the active sensor is not detected, Even if the active sensor is temporarily undetected, the active sensor will be deactivated after a predetermined time,
The presence of the human body can be reliably detected.

Further, the present invention makes it possible to prolong the life of the active sensor because the active sensor operates after the passive sensor detects the presence of the human body.

Further, in the present invention, the radiant heat from the human body is used in the pyroelectric sensor, but since it is of the differential type,
Or, since it is not used to detect a stationary human body,
It is possible to prevent malfunctions due to nearby heat sources and improve the accuracy of detecting the presence of the human body.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.

FIG. 2 is a diagram showing detection areas of a pyroelectric sensor and a distance measuring sensor.

FIG. 3 is a diagram showing a state in which the human body detection device is attached to a toilet.

FIG. 4 is a flowchart showing a processing flow.

FIG. 5 is a flowchart showing the flow of processing.

FIG. 6 is a time chart showing the flow of processing.

FIG. 7 is a diagram showing how a toilet is used.

FIG. 8 is a time chart showing the usage state of FIG. 7.

FIG. 9 is a diagram showing how a toilet is used.

FIG. 10 is a time chart showing the usage state of FIG.

[Explanation of symbols]

 3 Control circuit 4 Pyroelectric sensor 5 Distance measuring sensor

Claims (4)

[Claims] 1. A passive sensor for detecting the presence of a human body moving in a predetermined first detection area, and a stationary second detection area within the first detection area and narrower than the first detection area. An active sensor that detects the presence of a human body, and the detection output of the passive sensor activates the active sensor, the passive sensor is in a non-detection state, and the output of the active sensor is not detected from the detection state. When the state is changed, the active sensor is deactivated after a predetermined time, and the presence of the human body is detected during the predetermined time, based on the detection outputs of the passive sensor and the active sensor. A human body detection device comprising: a control unit that detects the presence of a human body. 2. A passive sensor for detecting the presence of a human body moving in a predetermined first detection area, and a stationary second detection area within the first detection area and narrower than the first detection area. And an active sensor for detecting the presence of a human body, the active sensor is activated by the detection output of the passive sensor, and when the output of the active sensor is in a non-detection state, the active sensor is activated after a predetermined time. Control means for detecting the presence of the human body based on the detection output of the passive sensor and the active sensor by detecting the presence of the human body for the predetermined time during the operation stop state. Human body detection device. 3. The human body detection device according to claim 1, wherein the passive sensor is a pyroelectric sensor that detects the presence of a human body based on infrared rays from the human body. 4. The human body detection device according to claim 1, wherein the active sensor is a distance measurement sensor that detects the presence of a human body based on a change in the measured distance.