JP3170677B2 - Infrared human body detector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a security human body detector for detecting movement of a human body by detecting infrared energy radiated from a human body or the like.

[0002]

2. Description of the Related Art This type of infrared detector constantly monitors the background of a monitored area, that is, the amount of infrared energy radiated from the surface of a floor, a wall, or the like. When blocked by a moving object having a different temperature, the total amount of infrared energy radiated from the background region fluctuates, and it is recognized that the moving object has entered the monitoring region based on the fluctuation of a certain amount or more. However, since the monitoring area cannot be limited by the conventional infrared detector, the detection beam of the infrared detector detects even small animals such as rats and cats wandering on the floor and issues an alarm (a false alarm is generated). Out). In addition, the object in the monitoring area or the housing of the infrared detector itself may be cooled or heated by the influence of the cool air, hot air, or the direct sunlight or reflection of the air by the draft air or the heating / cooling device, and a false alarm may be issued. Was. In addition, radio waves, electric noise, lightning surge, and the like may lead to a power supply line, a signal line, internal electronic components, and the like to give a false report. In addition, an erroneous report may be issued due to an insect crawling around the front surface of the optical system of the detector housing. Various proposals have been made to solve these problems. For example, for small animals, there is a method of reducing the ratio of the area blocked by the small animal to the area of the field of view projected on the floor surface by the detection beam (reducing the lack of visual field). If the temperature difference with the temperature became large, there was a case where a false report was issued. In addition, when a small animal climbs up to a high place such as a desk or a chair and approaches the detector, the lack of visual field becomes large and a false alarm may be issued. Also, for disturbances that do not enter / exit the detection beam, such as cool air, hot air, sunlight, etc. due to draft wind, heating / cooling equipment, and input to the infrared detection element without time lag, the infrared detection elements are connected in reverse to each other, and in phase. When input, the twin method is adopted to cancel each other and take out only the unbalanced output, but since the twin elements are not completely balanced, strong energy such as sunlight is applied to the infrared detection element. There is no effect in the case of direct incidence, and there is no effect in the case where a small animal moves along the arrangement direction of the twin elements. As a method for solving these problems, a double twin system in which twin elements are arranged in two stages, upper and lower, has been proposed. In this double twin system, the upper stage is set to look at the height of the chest or waist of the human body, the lower stage is set to look at the height of the legs, and an alarm output is issued when the unbalanced outputs of the upper and lower stages are in phase. It has become. However, since the detection element is housed in one package, there is a possibility that an erroneous report may be given when an insect or the like crawls and rolls on the housing in front of the optical system. As a result, the process for preventing false reports is complicated and expensive.

[0003]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the conventional apparatus, and its object is to provide a small animal, a draft wind, a cold wind by a heating / cooling device, a hot wind, a solar wind. An object of the present invention is to provide an inexpensive highly reliable infrared human body detector that eliminates false reports due to direct light, reflection, radio waves, electric noise, lightning surge, and crawling of insects.

[0004]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides an optical system for collecting infrared energy radiated from a human body or the like on an infrared detecting element by a collecting mirror. Is a compound eye infrared human body detector arranged at predetermined intervals along the direction of movement of the human body, the detection beams in the pair of optical systems, the edges of the plane crossed by the human body are substantially parallel to each other And the angles of the detection axes of the pair of optical systems are set so that the vertical directions are different from each other. Each of the optical systems has a timed circuit that is activated when there is an input fluctuation of a predetermined level or more,
When the activation time difference between the pair of optical system timed circuits exceeds a predetermined pulse width, A
An optical system for outputting an alarm from an alarm device based on the ND output, and for condensing infrared energy radiated from a human body or the like to an infrared detecting element by a condensing mirror. A compound eye infrared human body detector in which the optical systems are arranged at predetermined intervals along the direction of movement of the human body, wherein the detection beams in the pair of optical systems are arranged such that the edges of the surfaces traversed by the human body are mutually The optical axes are set so as to be substantially parallel, and the angles of the detection axes of the pair of optical systems are set so that the vertical directions are different from each other. Each of the optical systems has a timing circuit that is activated when there is an input fluctuation equal to or more than a predetermined level. In the pair of optical systems, the input of the time circuit of the optical system 1a and the output of the time circuit of the optical system 1b are output. Are ANDed, and the output of the timed circuit of the optical system 1a and the input of the timed circuit of the optical system 1b are ANDed, and when the activation time difference between the pair of optical systems exceeds a predetermined pulse width, The alarm device outputs resistances having different resistance values based on the AND-configured output.

[0005]

According to the present invention, a plurality of optical systems are arranged at predetermined intervals along the direction of movement of the human body, and the detection beams of the pair of optical systems are arranged such that the edges of the plane traversed by the human body are substantially parallel to each other. And the angles of the detection axes of the pair of optical systems are set so that the directions perpendicular to each other are different from each other. Each of the optical systems has a timing circuit that is activated when there is an input fluctuation equal to or more than a predetermined level, and when the activation time difference between the time circuits of the pair of optical systems exceeds a predetermined pulse width, the pair of optical systems has By outputting an alarm from the alarm device based on the AND output of the timed circuit of the optical system, the monitoring area can be limited to the range in which the human body moves, and the conditions for giving false alarms to small animals are severe. can do. Also, since infrared energy input to a pair of optical systems is output only when it is detected in a staggered manner, it is possible to provide a draft, a cool wind by a heater / cooler, a hot wind, direct sunlight, reflection, radio waves, and electric noise. Malfunctions due to input without time difference, such as lightning surge and lightning surge, are eliminated. Further, since the respective optical systems are arranged at a predetermined interval, false alarms due to crawling of the casing of insects or the like are greatly reduced. Further, in a pair of optical systems, the input of the timed circuit of the optical system 1a and the optical system 1b
And the output of the timed circuit of the optical system 1a and the input of the timed circuit of the optical system 1b are ANDed, and the activation time difference between the pair of optical systems has a predetermined pulse width. In the case of exceeding, the alarm device outputs resistances having different resistance values based on the output in the AND configuration. This has a great effect particularly when the monitoring method is a surface warning type. That is, it is possible to specify the moving direction of the human body, and to output each moving direction from the alarm device with a resistance having a different resistance value, thereby providing information of high security grade at a very low price. Also, since the monitoring area is simple, small animal countermeasures are easy.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings illustrating embodiments. Elements having the same numeral and supplementary characters have the same function, and the description with supplementary characters is omitted.
FIG. 1 is a circuit diagram of one embodiment of the present invention. 1 is an optical system,
Consisting of a condensing mirror, an infrared detecting element, an impedance conversion circuit, etc., the background of the monitoring area determined by the condensing mirror, that is, the amount of infrared energy radiated from the surface of a floor, a wall, etc. is always condensed on the infrared detecting element. When the monitoring area is blocked by a moving object different from the background temperature, the total amount of infrared radiation emitted from the background area fluctuates,
The variation is converted into an electric signal by the infrared detecting element and amplified by the amplifier circuit 2. When the variation exceeds a positive / negative threshold value set by the window comparator circuit 3, OR
Gate 4 outputs and activates timed circuit 7. The exclusive OR gate 8 pulsates the difference between the activation times of the timed circuits 7a and 7b, and the pulse width discrimination circuit 12 determines whether the pulse has a predetermined pulse width or more. If the pulse is longer than a predetermined pulse width, the control circuit 16 sends out a control signal. The output AND gates 17 and 18 open the gate by the control signal, and the alarm device 19 outputs the AND signal.
An alarm signal is output based on the result of the gate 17 or 18. If the difference between the activation times of the timed circuits 7a and 7b is equal to or smaller than a predetermined pulse width, the control circuit 16 does not send out a control signal, so that the gates of the output AND gates 17 and 18 remain closed.

FIGS. 2A and 2B are diagrams for explaining detection beams of a pair of optical systems according to the present invention. FIG. 2A is a plan view, and FIG. 2B is a side sectional view. 1 is a wall-mounted infrared human body detector.
Reference numerals 0 and 21 denote detection beams of the pair of optical systems 1a and 1b. The edges of the surface where the human body crosses the detection beams 20 and 21 are 20a and 21a, 20a as shown in the plan view (a).
b and 21b are substantially parallel to each other, and the distances D1 and D2 between the edges of each detection beam are set to be substantially equal. When the human body crosses the detection beam in the direction of arrow A, 20a and 21a are the leading edges of the detection beam, and when the human body crosses from the side opposite to the direction of arrow A, 21b and 20b are the leading edges of the detection beam. The angles of the detection axes of the detection beams by the pair of optical systems are set so that the vertical directions are different from each other as shown in the side sectional view (b). The field of view range that the detection beam 20 projects on the floor surface is a side sectional view (b).
The optical system 1a may output a detection signal when a small animal walks in this range as shown in FIG. Similarly, a range in which the detection beam 21 may generate a detection signal by a small animal is a range of positions P2 to P2 ′.
As shown in FIG. 2 (b), the height of the chest of the human body H
By setting it at the position 2, it is possible to set the monitoring area up to the distance L1 at the intersection of the detection beam 21 and the height H1 of the leg. As described above, the pair of optical systems 1a and 1b
By setting the detection axes of the detection beams different from each other in the vertical direction, the visual field range of each detection beam projected on the floor surface can be separated, and the AN of the two detection beams can be separated.
By taking out the D output, it is possible to limit the monitoring area for the crossing of the human body and to make false alarms by small animals extremely unlikely to occur. In the above, the condition in which the small animal generates a false alarm is that the small animal passes within the field of view where any of the detection beams project on the floor, and then within a predetermined time, the field of view where the other detection beam projects on the floor. As a result, the smaller the animal, the smaller the probability that a false alarm will be generated as the visual field range projected on the two floors becomes farther. In addition, the detection beam 20 in the portion beyond the monitoring area L1
Or, if 21 is blocked by a wall or the like so that the visual field range is not physically projected on the floor, false alarms by small animals are completely eliminated.

FIGS. 3 and 4 are operation waveform diagrams of respective parts of the circuit of the embodiment shown in FIG. FIG. 3 shows an example in which the activation time difference T1 between the timed circuits 7a and 7b exceeds a predetermined pulse width T3, and FIG. 4 shows an example in which the pulse width is less than the predetermined pulse width T3. The pulse width T3 is determined by the distance between the optical systems 1a and 1b and the maximum moving speed of the human body to be detected. For example, if the distance between the optical systems 1a and 1b is 10 cm and the maximum moving speed of the human body to be detected is 5 m / s, the pulse width T3 is 20 ms.

The circuit of one embodiment of FIG. 1 will be described below with reference to FIG.
A detailed description will be given with reference to the operation waveforms of the respective units in FIG. The signal output from each of the optical systems 1a and 1b is supplied to an amplifying circuit 2a.
And 2b are amplified and input to the window comparator circuits 3a and 3b. The signals exceeding the positive and negative thresholds of the window comparator circuits are shaped as detection signals and input to the OR gates 4a and 4b. FIG.
2A and 2B show the outputs of the OR gates 4a and 4b when the human body crosses the detection beams 20 to 21 in the direction of arrow A in the monitoring area shown in FIG. FIG.
(A) and (b) are examples in which outputs appear on the OR gates 4a and 4b due to reasons other than the movement of the human body.

The outputs of the OR gates 4a and 4b are
The signals are input to the trigger terminals A of the monostable multivibrators 5a and 5b constituting the timed circuits 7a and 7b, respectively. The monostable multivibrators 5a and 5b synchronize with the rise of the signal input to each trigger terminal A,
As shown in FIGS. 3 and 4 (c) and (d), respectively.
Each output terminal Q generates a pulse having a pulse width T2 and T2 '. The pulse widths T2 and T2 'are determined by the optical system 1
It is determined by the separation distance between a and 1b and the minimum moving speed of the human body to be detected, and it is desirable that the pulse widths T2 and T2 'be as equal as possible. For example, the optical system 1a
Assuming that the separation distance between the robot and the sensor 1b is 10 cm and the minimum moving speed of the human body to be detected is 0.2 m / s,
The pulse widths T2 and T2 'of a and 7b are 500 ms. Therefore, the monostable multivibrators 5a and 5
The output pulse width of b is adjusted by the capacitors C1 and C2 and the resistors R1 and R2 so as to be 500 ms.

The start time difference T1 between the timed circuits 7a and 7b
Corresponds to each of the monostable multivibrators 5a and 5b.
It is determined by measuring the rising time interval.
In this embodiment, the monostable multivibrator 5a and
5b through the exclusive OR gate 8,
Each output of the monostable multivibrators 5a and 5b is
Extract the time zone that does not match, and
The pulse width discrimination circuit 12 determines whether the pulse width exceeds the pulse width T3.
Is determined. The pulse width discrimination circuit 12
Output if the matching time period exceeds the predetermined pulse width T3
However, when the pulse width is equal to or less than the pulse width T3, no output is performed. FIG. 3 and
FIG. 4E shows the output of the exclusive OR gate 8,
Outputs of the stable multivibrators 5a and 5b do not match
Indicates that "H" is output. The pal
The width discrimination circuit 12 includes a monostable multivibrator 9, D
A flip-flop 10 and an inverter 11;
The monostable multivibrator 9 is provided with the exclusive OR gate.
3 and 4 in synchronization with the rising edge of the output of FIG.
Output terminal as shown in (f) From the pulse width T3
Luss occurs. This pulse is applied to the D flip-flop 1
0 to the clock terminal CK and the D flip-flop
Of the exclusive OR gate 8 input to the terminal D of the
The output is longer than the pulse width T3 as shown in FIG.
3 in synchronization with the fall of the pulse width T3,
(G) As shown in FIG.
"H" is output to the input terminal Q. The D flip-flop
The output of the exclusive OR gate 8 input to the terminal D
The force is shorter than the pulse width T3 as shown in FIG.
At the time when the pulse width T3 falls.
The terminal D of the D flip-flop 10 is "L".
Therefore, the output terminal Q of the D flip-flop 10
As shown in FIG. 4 (g), there is no change in the state of “L”.

The pulse width discriminating circuit 12 outputs the signal from the output terminal Q of the D flip-flop 10 and inputs it to the clock terminal CK of the D flip-flop 15 constituting the control circuit 16. On the other hand, the terminal D of the D flip-flop 15 is connected to timed circuits 7a and 7b as shown in FIG.
Is activated by the NOR gate 13 and the inverter 14 during the startup, the D flip-flop 1
5 in synchronization with the rise of the clock terminal CK from the output terminal Q as shown in FIG.
Is sent to each input terminal of the AND gates 17, 18a and 18b. This control signal “H” continues until the clear terminal CL of the D flip-flop 15 is set to “H”. Therefore, as shown in FIG. 3 (j), when the difference T1 between the activation of the timed circuits 7a and 7b is equal to or greater than the pulse width T3, the AND gate 17 outputs the pulse width T2 of the timed circuit 7a and the pulse width T2 of the timed circuit 7b. 'And output.
When the activation time difference T1 is equal to or less than the pulse width T3, the terminal D of the D flip-flop 10 at the falling point of the pulse width T3 is "L", so that the output terminal Q of the D flip-flop 10 , As shown in FIG. 4 (g). Therefore, the output terminal Q of the D flip-flop 15 of the output control circuit 16 does not output a control signal as shown in FIG. 4 (i), and the AND gate 17 has no output as shown in FIG. 4 (j). Even if the activation time difference T1 between the timed circuits 7a and 7b is equal to or greater than the pulse width T3, if the pulse width T2 'is not activated while the pulse width T2 is activated, there is no output from the AND gate 17. Eventually, the condition that the AND gate 17 outputs is that the infrared energy is input to the pair of optical systems with a time difference equal to or greater than the pulse width T3, and the pulse width T2 (T2 ') of one of the timed circuits.
During the start, the pulse width T2 '(T2) of the other timed circuit
It is time to start. In addition, even when the human body moves from the optical system 1b to the optical system 1a, the same description can be given as above, and the description is omitted.

Next, in the pair of optical systems 1a and 1b of FIG. 1, the output of the timed circuit 7a of the optical system 1a and the optical system 1b
The circuit operation in which the input of the timed circuit 7b is ANDed will be described. This is a circuit for identifying the direction in which the human body has moved from the optical system 1a to the optical system 1b in FIG. 2A, and the output is obtained by an AND gate 18b. AND gate 1
Reference numeral 8b denotes a three-input AND gate which receives the output of the OR gate 4b, the output of the output terminal Q of the monostable multivibrator 5a of the timed circuit 7a, and the output of the output terminal Q of the D flip-flop 15 of the control circuit 16. ing. If the activation time difference T1 between the timed circuits 7a and 7b exceeds the predetermined pulse width T3, the output terminal Q of the D flip-flop 15 becomes "H" as shown in FIG.
The ND gate 18b outputs the AND of the output of the OR gate 4b and the output of the output terminal Q of the monostable multivibrator 5a. For example, the human body is moved from the optical system 1a to the optical system 1b.
To the OR gates 4a and 4b, respectively, as shown in FIG.
When the signals (a) and (b) are output, the output of the AND gate 18b is output from the OR gate 4b as shown in FIG. Further, the alarm device 19 is provided with the AND
Upon receiving the output signal of the gate 18b, for example, the resistance value R1
Output the resistance of If the time difference T1 between the timed circuits 7a and 7b is equal to or less than the pulse width T3, the pulse width discrimination circuit 12 does not output as described above.
6 does not output a control signal. Therefore, the AND gate 18b also does not output. Also, the timed circuit 7 of the optical system 1b
The circuit in which the output of b and the input of the timed circuit 7a of the optical system 1a are ANDed is a circuit for identifying that the human body has moved from the optical system 1b to the optical system 1a, and the output is an AND gate 18a.
Obtained by The alarm device 19 receives the output signal of the AND gate 18a and outputs, for example, a resistance having a resistance value R2.

FIGS. 5 and 6 show another embodiment of the present invention.
It is a figure explaining the detection beam of a ceiling-mounted infrared human body detector, (a) is a top view and (b) is a side sectional view. FIG.
Is a pair of two optical systems, and FIG.
The two optical systems are arranged in two rows in parallel along the moving direction of the human body, and two optical systems in the front row and two optical systems in the rear row are paired.

FIG. 5 shows a ceiling-mounted infrared human body detector 24.
FIG. 4 is a view for explaining the detection beams of a pair of optical systems. ing. As shown in the side sectional view (b), the range of the field of view that each detection beam projects on the floor surface is as follows: the detection beam 25 is at the positions P1 to P1 ',
If the height of the human body detection site is H1 for the legs and H2 for the chest, the monitoring area is at L1 to L2 as shown in FIG. Become.

FIG. 6 shows a case where a pair of optical systems is added to extend the monitoring area L1 to extend the monitoring area L1 to L2 of FIG.
L3. In addition to the optical systems 25 and 26 in FIG. 5, a pair of optical systems 29 and 30 are further provided along the moving direction of the human body, and the monitoring areas L2 to L3 are added.
The overall monitoring area was L1-L3. The basic operation is the same as that of FIG.

As described above, regarding the pair of optical systems, the optical system 1
Although the description has been made using one detection beam for each unit, the present invention is not limited to this. As an optical system,
A plurality of detection beams may be radially arranged by using a condenser mirror in which a concave mirror is divided and each focal point of a plurality of reflection mirrors is focused on an infrared detecting element. Further, a twin element can be used as the infrared detecting element. As long as the angles of the detection beams of the pair of optical systems are different from each other and the edges are substantially parallel, the same effect can be obtained regardless of the number of the detection beams. Further, the pair of optical systems can be arbitrarily selected from a plurality of optical systems as long as the above conditions are satisfied,
Duplicate selections may be made.

[0018]

Since the present invention is configured as described above, it has the following effects.

It is possible to limit the monitoring area, which has been impossible with the infrared human body detector, so that small animals can wander around the floor,
False alarms due to insects crawling on the housing can be significantly reduced. Also, in addition to the conventional voltage level, time factors such as the maximum speed and the minimum speed at which the human body moves are adopted as conditions for detecting the human body, so that the movement of the human body is significantly differentiated from other disturbances. It is possible to remarkably eliminate false reports due to sunlight, radio waves, noise, environmental factors, and the like.

Further, when the present invention is applied to a surface-guard type infrared human body detector, an infrared human body detector which completely eliminates false alarms by small animals can be realized by limiting the monitoring area, and the movement of the human body can be realized. By specifying the directions with resistances having different resistance values and outputting the results, it is possible to construct an advanced security system at low cost.

[Brief description of the drawings]

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

FIG. 2 is an explanatory view of a detection beam of the wall-mounted infrared human body detector of the present invention.

FIG. 3 is a waveform diagram of each part of the circuit diagram of one embodiment.

FIG. 4 is a waveform of each part of the circuit diagram of one embodiment.

FIG. 5 is an explanatory view of a detection beam of the ceiling-mounted infrared human body detector of the present invention.

FIG. 6 is an explanatory view of a detection beam of the ceiling-mounted infrared human body detector of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Wall-mounted infrared human body detector 2 ... Amplifier circuit 3 ... Window comparator circuit 4 ... OR gate 5 ... Monostable multivibrator 7 ... Timed circuit 8 ... Exclusive OR circuit 9 ... Monostable multivibrator 10 ... D flip-flop DESCRIPTION OF SYMBOLS 11 ... Inverter 12 ... Pulse width discrimination circuit 13 ... NOR gate 14 ... Inverter 15 ... D flip-flop 16 ... Output control circuit 17 ... AND gate 18 ... AND gate 19 ... Alarm device 24 ... Ceiling-mounted infrared human body detector 28 ... Ceiling Mountable infrared human body detector

Claims (2)

(57) [Claims] 1. A compound eye in which an infrared system radiated from a human body or the like is condensed on an infrared detecting element by a condensing mirror, and the optical system is arranged at a predetermined interval along a moving direction of the human body. An infrared human body detector,
The detection beams in the pair of optical systems are set so that the edges of the plane traversed by the human body are substantially parallel to each other, and the angles of the detection axes of the pair of optical systems are set so that the directions perpendicular to each other are different from each other. Each of the optical systems has a timing circuit that is activated when there is an input fluctuation equal to or more than a predetermined level, and when the activation time difference between the time circuits of the pair of optical systems exceeds a predetermined pulse width, the pair of optical systems is used. AND of timed circuit of optical system
An infrared human body detector, wherein an alarm is output from an alarm device based on the output. 2. A compound eye in which an infrared system radiated from a human body or the like is condensed on an infrared detecting element by a converging mirror, and the optical systems are arranged at predetermined intervals along a moving direction of the human body. An infrared human body detector,
The detection beams in the pair of optical systems are set so that the edges of the plane traversed by the human body are substantially parallel to each other, and the angles of the detection axes of the pair of optical systems are set so that the directions perpendicular to each other are different from each other. Each of the optical systems has a timing circuit that is activated when there is an input fluctuation equal to or more than a predetermined level. In the pair of optical systems, the input of the time circuit of the optical system 1a and the output of the time circuit of the optical system 1b are output. Are ANDed, and the output of the timed circuit of the optical system 1a and the input of the timed circuit of the optical system 1b are ANDed, and when the activation time difference between the pair of optical systems exceeds a predetermined pulse width, The infrared human body detector according to claim 1, wherein the alarm device outputs resistances having different resistance values based on the AND-configured output.