JP2551019Y2 - Intrusion alarm 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 intrusion alarm device which optically detects an intruder and outputs an alarm, and particularly to a light emitting device and a light receiving device which constitute the intrusion alarm device during maintenance work. Remove the cover provided on the front and operate the test mode switch provided inside the housing.
The present invention relates to an intrusion alarm device having a function of coping with forgetting to return a test mode switch after adjusting the functions of those devices.

[0002]

2. Description of the Related Art An intrusion alarm device for optically detecting an intruder has a light projecting device and a light receiving device with a guard space interposed therebetween, and light from the light projecting device is projected on the light receiving device so as to fill the guard space. When an intruder crosses and cuts off the optical path formed between the light emitting device and the light receiving device, it detects that the light from the light emitting device is not received by the light receiving device and outputs an alarm, and enters the alert space. Detects intruders who have taken action.

A protective cover is attached to the front of each of the light emitting device and the light receiving device of the intrusion alarm device.
The protective cover is removed by mischief, or an intruder deliberately removes the protective cover of the light emitting device or light receiving device, and modifies the internal circuit of the light emitting device or light receiving device to disable the intruder detection function. Can be considered.
In order to prevent such an action, a function is provided in which when the cover of the light emitting device is removed, a tamper (mischief) detection switch is automatically activated to stop the light emission from the light emitting device. When the light emission from the light emitting device is stopped, the light receiving device outputs an alarm in the same manner as when an intruder enters the guard space and cuts off the optical path. When the cover of the light receiving device is removed, the tamper detection switch in the light receiving device is activated, and an alarm is output from the light receiving device.

In some cases, internal maintenance operations such as checking the operation of the internal circuits of the light projecting device and the light receiving device and adjusting the optical axis are performed. At the time of such maintenance work, a maintenance worker removes the cover and performs maintenance work. If the projection of the light emitting device is stopped and the light emitting device is stopped, the maintenance operation on the light receiving device cannot be performed. Therefore, a test mode switch is provided inside the light emitting device. When the test mode switch inside the projector is removed and the test mode switch is set to the test mode,
Light is emitted even when the cover of the light emitting device is removed.
After removing the cover of the light-receiving device, the test mode switch is operated to change the operating conditions of the internal circuit of the light-receiving device, and the operation is confirmed by lowering the light-receiving sensitivity from the light-receiving sensitivity (gain) of normal operation. You can also.

[0005]

After the maintenance work is completed, the maintenance person usually returns the test mode switch of the light emitting device to the normal operation mode and then attaches the cover. However, if maintenance personnel forget to return the test mode switch to the normal operation mode,
Even if an intruder removes the cover and activates the tamper detection switch, there is a problem that the light emission does not stop, no alarm is output, and the test mode is continued. Similarly, after maintenance is completed, if the cover is attached with the tester's test mode switch set to the test mode after the maintenance work is completed, the tamper-prevention switch operates but remains in the test mode. Has a problem that the test mode operating condition remains. Another problem is that the maintenance worker leaves the test mode switch in the test mode and forgets to attach the cover. Therefore,
SUMMARY OF THE INVENTION It is an object of the present invention to provide an intrusion alarm device capable of detecting forgetting to return a test mode switch of a light emitting device to a normal operation mode. Another object of the present invention is to
An object of the present invention is to provide an intrusion alarm device that can appropriately cope with a case where the user forgets to return the test mode switch of the light receiving device to the normal operation mode.

[0006]

Means for Solving the Problems To solve the above problems, there is provided a light projecting device disposed opposite the optical axis and a light receiving device for detecting the presence or absence of light from the light projecting device. The light emitting device is provided with a cover and a test mode switch operated by removing the cover. When the cover is removed, the switch operates to stop light emission to the light receiving device. In the intrusion alarm device configured to emit light in the test mode in which the light emitting device is operated, the light emitting device causes the light emitting device to terminate the test mode after a lapse of a predetermined time after the test mode switch is set to the test mode. Means were provided. In order to solve the above-mentioned problem, a light projecting device disposed opposite to the optical axis and a light receiving device for detecting the presence or absence of light from the light projecting device are provided. A test mode switch is provided for removing the cover for operation, and the light receiving device is configured to perform a test by changing an operating condition of its internal circuit when the cover is removed and the test mode switch is operated to set the test mode. In the intrusion alarm device described above, the light receiving device is provided with means for terminating the test mode after a predetermined time elapses after the test mode switch is set to the test mode and returning the operating condition of the internal circuit to the normal operating condition. . Preferably, the intrusion alarm device of the present invention comprises a light emitting device and a light receiving device having the above-mentioned means.

[0007]

The cover is attached without returning the test mode switch by means for terminating the test mode and returning to the normal operation mode after a predetermined time has elapsed after operating the test mode switch provided on the light emitting device. At this time, the test mode is automatically terminated and the light emitting device enters a normal operation state. A means provided in the light receiving device for returning from the test mode to the normal operation mode after a predetermined time has elapsed after the operation of the test mode switch and returning the internal circuit of the light receiving device to the normal operation state. Processing can resume.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the intrusion alarm device of the present invention will be described with reference to FIGS. FIG. 1 is an overall configuration diagram of an intrusion alarm device according to an embodiment of the present invention. FIG. 2 is a circuit configuration diagram of the light receiving device 3 shown in FIG. The intrusion alarm device is a security space 5
And a light-emitting device 1 and a light-receiving device 3 arranged to face each other. An optical path is defined between the light projecting device 1 and the light receiving device 3. In the normal operation mode, the light emitting device 1
The light is radiated to the light receiving device 3 from the security space 5 through the guard space 5. Therefore, when the intruder crosses the security space 5 for a predetermined time, the optical path is cut off, and the light receiving device 3 outputs an intrusion alarm.

The circuit configuration for detecting the intruder and its operation will be described. The light emitting device 1 includes a light emitting device housing 10,
The light emitting diode (LE) housed in the housing 10
D) drive circuit 11, test mode end timer circuit 12,
The contact 12 a of the timer circuit 12, the test mode switch 15 provided in the housing 10, the tamper detection switch 16 that operates when the cover 21 is removed from the housing 10, the oscillation circuit 17, and the LED drive circuit 11 are driven. LED 18 and a lens 19 for converting light from the LED 18 into parallel light. The oscillation circuit 17 is an LED
An oscillation signal for energizing the LED 18 via the drive circuit 11 is generated. The oscillation frequency is shorter than the timer of the alarm detection timer circuit 52 in the light receiving device 3 described later. A cover 21 having a light transmitting portion 21a is attached to the front surface of the lens 19 in the light projecting device housing 10. The cover 21 has a light-transmitting portion 21a formed of a light-transmitting member, for example, glass, and the other portions are formed of opaque plastic or opaque metal. In addition, this cover 2
As 1, the front surface may be entirely formed of a transparent material such as acrylic.

In the configuration shown in FIG. 1, the light receiving device 3 has a light receiving device housing 30, a lens 31a, a photodiode (or phototransistor) 32a, a light receiving circuit 33a, and an amplifier circuit housed in the housing 30. 34a and an alarm circuit 35a. A cover 61 having a light transmitting portion 61a is attached to the light receiving device housing 30 in front of the lens 31a. Cover 61 and translucent section 6
1a is manufactured in the same manner as the cover 21 and the light transmitting portion 21a described above.

The phototransistor 32 shown in FIG.
a, light receiving circuit 33a, amplifying circuit 34a and alarm circuit 3
FIG. 2 shows a more detailed circuit configuration of the signal processing circuit 3A inside the light receiving device 3 that more accurately represents the whole 5a. The internal signal processing circuit 3A of the light receiving device 3 includes a bias control circuit 3
1, a phototransistor 32 and a preamplifier 33. The internal signal processing circuit 3A of the light receiving device 3 includes a selection resonance circuit 38, a variable amplification circuit 42, a detection circuit 48, an amplification circuit 49, a tone decoder 51, and an alarm detection timer circuit 5.
2, an automatic gain control (AGC) circuit 50 and a sensitivity switching circuit 43 are provided. Further, the internal signal processing circuit 3A of the light receiving device 3 has a channel selection switch circuit 39 and a resonance switching circuit 40. The internal signal processing circuit 3A of the light receiving device 3 includes a tamper detection switch 44, a test mode switch 56, a test mode end timer circuit 57, its contact 57a, a control circuit 46, a relay drive control circuit 53, a relay 54, and an alarm output. It has a portion 55. The variable amplifying circuit 42, the sensitivity switching circuit 43, and the control circuit 46 constitute a gain switching circuit 41. The gain switching circuit 41 changes the gain of the variable amplifier circuit 42 between the normal mode and the test mode.

In the normal operation mode, the test mode end timer circuit 12 in the light emitting device 1 is in a timer expired state, and its contact 12a is in an open state indicated by a broken line in the figure. When the test mode switch 15 is not in the test mode state, the test mode switch 15 is in the deenergized state, and its contact is at the open position shown by the broken line in the figure. Furthermore, tamper detection switch 1
Reference numeral 6 denotes a closed state shown by a solid line in the drawing when the cover 21 is attached to the light emitting device housing 10. Therefore, in the normal operation mode in which the cover 21 is attached, the tamper detection switch 16 is closed, the oscillation signal from the oscillation circuit 17 is applied to the LED drive circuit 11, and the LED drive circuit 11 The LED 18 is energized in response to the oscillation signal. LED 18 is L
Light is emitted in response to a drive signal from the ED drive circuit 11, and its light output is converted into parallel light by a lens 19 and radiated to the guard space 5 via the light transmitting portion 21 a of the cover 21.

The lens 19 in the light emitting device 1 and the lens 31a in the light receiving device 3 are opposed to each other via the security space 5, and an optical path is defined between them. The light from the lens 19 is applied to a cover 61 provided on the front surface of the light receiving device 3.
Is received by the lens 31a through the light transmitting portion 61a. The light received is actually the phototransistor 3 shown in FIG.
2 and is converted into an electric signal. The electric signal from the phototransistor 32 is biased by the bias control circuit 31, and the electric signal photoelectrically converted by the phototransistor 32 is amplified by the preamplifier 33 and input to the selective resonance circuit 38.

The signal applied to the selective resonance circuit 38 is selectively resonated in response to a resonance signal signal S40A from a resonance switching circuit 40 that switches the resonance frequency in response to the channel selected by the channel selection switch circuit 39. . The resonance signal of the selective resonance circuit 38 is amplified by the variable amplifier circuit 42 and detected by the detection circuit 48 for detecting a signal corresponding to the light projection signal from the light projecting device 1.
Amplified at 9. A series circuit of the AGC circuit 50 and the sensitivity switching circuit 43 is provided in parallel with the series circuit including the variable amplifier circuit 42 to the amplifier circuit 49, and the gain is automatically adjusted to the detection signal. The output from the amplifying circuit 49 is applied to the tone decoder 51, and the presence / absence of an intruder is decoded (determined) by the tone decoder 51, and the determination signal is applied to the alarm detection timer circuit 52.

In normal operation, the light emitted from the light emitting device 1 is detected by the detection circuit 48 in the light receiving device 3, and the tone decoder 51 detects the presence of the light emitted from the light emitting device 3 and outputs the alarm detection timer circuit 5
2 is driven. After a lapse of a predetermined time from when the alarm detection timer circuit 52 is driven, for example, 0.01 seconds to 0.1 seconds.
After a lapse of about a second, a timer expiration signal S52 is output when the timer expires. When the intruder enters the guard space 5 and exceeds the timer of the alarm detection timer circuit 52, the time guard space 5
When the light enters the light receiving device 3, the light from the light emitting device 1 is not received by the light receiving device 3, the alarm detection timer circuit 52 expires, and the timer expiration signal S52 is output to the control circuit 46. The control circuit 46 activates the relay drive control circuit 53 to drive the relay 54, and drives the corresponding alarm circuit in the alarm output unit 55 to output an alarm.

The maintenance work in the light receiving device 3 will be described. When the cover 61 is removed from the light receiving device housing 30, the tamper detection switch 44 operates to bring its contact into an open state. When this opening signal is input to the control circuit 46,
The control circuit 46 activates the relay drive control circuit 53, drives the relay 54, and inputs a signal to the alarm output unit 55. However, at the time of maintenance work, the alarm output unit 55 is set in the released state in advance, so that this alarm is not reported to the security center. The test mode switch 56 is in the open state shown by the solid line in the normal operation mode, but is closed when operated by a maintenance worker to set the test mode. When the test mode switch 56 is set to the test mode state, the test mode end detection timer circuit 57 is activated, and the timer expires after a lapse of a predetermined time obtained by adding a margin to the test mode work time, for example, 10 minutes. , The contact 57a is opened. When the test mode switch 56 is set to the test mode state, the setting state is detected by the control circuit 46, and the control circuit 46 stops the alarm by the operation of the tamper detection switch 44. Further, the control device 46 lowers the sensitivity of the variable amplifier circuit 42 via the sensitivity switching circuit 43. This drop in sensitivity is particularly likely during maintenance work, especially when the light-emitting device
This is performed in order to test that the light projection from the light receiving device 3 can be detected.

In the normal operation mode, when an intruder does not enter the caution space 5, the optical path between the light projecting device 1 and the light receiving device 3 is not cut off, so that the lens 31a emits light from the light projecting device 1. Receive light. Therefore, the signal resonated by the selective resonance circuit 38 is detected by the detection circuit 48, and the tone decoder 51 decodes that there is no intruder. The alarm detection timer circuit 52 is driven by the tone decoder 51 at a predetermined cycle, the timer does not expire, and the timer expiration signal S52 is not output. Therefore, no alarm is output from the alarm output unit 55. On the other hand, for some reason, the light receiving device 3
When there is no light received by the lens 31a in the inside, the tone decoder 51 determines that the intruder has entered the caution space 5 and does not drive the alarm detection timer circuit 52.
When the timer expires, an alarm is output from the alarm output unit 55.

The overall maintenance operation in FIG. 1 will be described. First, the maintenance worker first moves the cover 21 from the light emitting device housing 10.
Remove. At this time, since the test mode switch 15 is still in the open position indicated by the broken line in the figure, the oscillation signal from the oscillation circuit 17 to the LED drive circuit 11 is interrupted. As a result, the LED 18 is extinguished. Since the light emission from the light emitting device 1 to the light receiving device 3 is interrupted by the deenergization of the LED 18, the signal to be detected does not exist in the detection circuit 48 shown in FIG.
The state is determined, and the timer circuit 52 is not started. As a result, the timer of the timer circuit 52 expires after the predetermined time elapses, and the signal is input to the alarm output unit 55. However, at the time of maintenance work, the alarm output unit 55 is set in the released state in advance, so that no alarm is reported to the security center.

Immediately after removing the cover 21, the maintenance staff operates the test mode switch 15 to set the test mode. As a result, an oscillating signal is applied from the oscillating circuit 17 to the LED driving circuit 11 via the test mode switch 15 and the contact 12a, and the LED 18 is driven and the lens 1 is driven.
From 9, light is emitted to the light receiving device 3. Thereby, light reception in the light receiving device 3 is restarted, and various tests and adjustments in the test mode can be performed. With the test mode switch 15 set to the test mode, the maintenance person performs various maintenance operations, for example, operations such as adjusting the gain of the LED drive circuit 11. The test mode end detection timer circuit 12 starts the timer when the test mode switch 15 is set to the test mode. When the test mode switch 15 remains in the test mode even after the elapse of the predetermined time, the timer of the test mode end detection timer circuit 12 expires. When the timer expires, the contact 12a of the test mode end detection timer circuit 12 becomes the open state shown by the broken line in the figure. As a result, the oscillation circuit 17 outputs L
The signal path to the ED drive circuit 11 is cut off,
D18 goes out.

The expiration time of the timer of the test mode end detection timer circuit 12 is designed to be a time which has a margin to the usual required time for executing the test mode, for example, about 10 minutes. When the maintenance work is performed for a long time and exceeds the time-out time of the test mode end detection timer circuit 12, the test mode switch 15 is set to the normal operation mode once to prevent the alarm from being output. And the test mode end timer circuit 12 is reset, and the test mode switch 15 can be set to the test mode again.

After the maintenance work is completed, the maintenance person first returns the test mode switch 15 to the position shown by the broken line in the figure, and attaches the cover 21. When the test mode switch 15 returns to the normal operation mode, the test mode end detection timer circuit 12 is reset, and the contact 12a remains at the position indicated by the solid line in the figure.

On the other hand, the maintenance person
Even if the cover 21 is attached without forgetting to return to the normal operation mode, the tamper detection switch 16 is closed, and the oscillation signal is applied from the oscillation circuit 17 to the LED drive circuit 11 through the tamper detection switch 16. You. The timer of the timer circuit 12 expires after the predetermined time elapses, and the contact 12a is opened. However, since the oscillation signal is supplied to the LED drive circuit 11 through the path of the tamper detection switch 16, the LED 18 continues to light. . Also,
If the maintenance worker forgets to return the test mode switch 15 to the normal operation mode and forgets to attach the cover 12, the test mode end timer circuit 12 continues to operate for a predetermined time while the tamper detection switch 16 remains open. Later, the timer expires and the contact 12a is opened, so that no oscillation signal is applied from the oscillation circuit 17 to the LED drive circuit 11, and light emission stops. Therefore, a light is not received by the light receiving device 3 and an alarm is output, so that it is possible to detect that the cover is left unattended.

When performing maintenance work on the light receiving device 3, the maintenance person first removes the cover 61 from the light receiving device housing 30. As a result, the tamper detection switch 44 changes from the closed state shown by the broken line in FIG. 2 to the closed state shown by the solid line, and the control circuit 46 outputs an alarm. Immediately after that, the maintenance person sets the test mode switch 56 to the test mode. As a result, the test mode end detection timer circuit 57 is activated, and
The control circuit 46 stops the alarm and lowers the sensitivity of the variable amplifier circuit 42 via the sensitivity switching circuit 43. The maintenance worker performs maintenance work in the state where the sensitivity is lowered.

When the maintenance work is completed, the maintenance person first returns the test mode switch 56 from the test mode to the normal mode. As a result, the signal S56 becomes “low” level. When the test mode switch 56 returns to the normal mode, the test mode end detection timer circuit 57
Stops. Therefore, the contact 57a of the test mode end detection timer circuit 57 remains in the state shown by the solid line in the figure. The control circuit 46 returns the gain of the variable amplifier circuit 42 to the gain of the normal mode via the sensitivity switching circuit 43 in response to the return from the test mode to the normal mode.
Therefore, thereafter, the variable amplifier circuit 42 performs amplification at a high gain in normal operation.

If the maintenance worker forgets to return the test mode switch 56 to the normal mode, the light receiving device housing 3
When the cover 61 is attached to the control circuit 0, the test mode end detection timer circuit 57 is turned off after a predetermined time has elapsed after the test mode switch 56 is set to the test mode, and the contact 57a is automatically opened. 46 returns the gain of the variable amplifier circuit 42 to the gain in the normal operation state. As a result, the variable amplifier circuit 42 in the light receiving device 3 performs an amplification operation with a normal gain.

As described above, the test mode switch 5
Even if the cover 61 is attached to the light receiving device housing 30 while forgetting to return the 6 to the normal mode, the test mode is automatically returned after a predetermined time has elapsed.

In order to implement the present invention, in addition to the above configuration,
Various modifications can be made using other components that perform the same functions as the above-described functions, for example, using a microcomputer that performs the same processing as the above-described processing. In the above-described embodiment, the intruder detection using light is described. However, the present embodiment is not limited to the optical intruder detection, and an intruder detection method using a radio wave.
The present invention can be applied to other detection methods such as an intruder detection method using ultrasonic waves.

[0028]

As described above, according to the present invention, the test mode is automatically restored after a lapse of a predetermined time even if the test mode switch in the light emitting device or the light receiving device is forgotten to return to the normal mode. Is done.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of an intrusion alarm device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a first example of the light receiving device of the intrusion alarm device shown in FIG.
FIG. 3 is a diagram illustrating the configuration of a signal processing circuit according to an embodiment.

[Explanation of symbols]

1 .... light emitting device, 3 .... light receiving device, 5 .... warning space, 1
0 ... light emitting device housing, 11 ... LED drive circuit, 12 ...
· Test mode end detection timer circuit, 15 · · · Test mode switch 16 · · · Tamper detection switch · 17 · · ·
Oscillation circuit, 18 LED, 19 lens, 21
Cover, 21a-light-transmitting portion, 30-light-receiving device housing, 3
1a lens, 32a phototransistor 33a
..Light receiving circuit, 34a..amplifying circuit, 35a..alarm circuit, 3A..internal signal processing circuit of light receiving device, 31..bias control circuit, 32..phototransistor, 33 ..
.. Preamplifier, 38... Selective resonance circuit, 39... Channel selection switch circuit, 40... Resonance switching circuit, 41.
Gain switching circuit, 42 ··· Variable amplification circuit, 43 ··· Sensitivity switching circuit, 44 ··· Tamper detection switch, 45 ··· Tamper detection timer circuit, 46 ··· Control circuit, 48 ··· Detection circuit, 49 ··· Amplification circuit , 50 AGC circuit, 51
.Tone decoder 52, alarm detection timer circuit 53
..Relay drive control circuit, 54..Relay, 55..Alarm output unit, 56..Test mode switch, 57..Test mode end timer circuit, 61..Cover, 61a.
-Translucent part.

Claims (3)

(57) [Scope of request for utility model registration] A light-emitting device disposed opposite the optical axis and a light-receiving device for detecting the presence or absence of light from the light-emitting device, wherein the light-emitting device includes a cover and a cover. A test mode switch is provided that operates when the cover is removed, and the switch operates to stop emitting light to the light receiving device while emitting light in the test mode in which the test mode switch is operated. An intrusion alarm device as described above, wherein the light emitting device is provided with means for terminating the test mode after a lapse of a predetermined time after the test mode switch is set to the test mode. apparatus. 2. The light receiving device is provided with a cover and a test mode switch for removing and operating the cover. The light receiving device has an internal circuit when the cover is removed and the test mode switch is operated to set the test mode. After the test mode switch is set to the test mode, the photodetector ends the test mode after a predetermined time has elapsed, and normally sets the operation conditions of the internal circuit. 2. The intrusion alarm device according to claim 1, further comprising means for returning to an operating condition. 3. A light-emitting device disposed opposite to the optical axis and a light-receiving device for detecting the presence / absence of light from the light-emitting device. A test mode switch for operation is provided, and when the test mode switch is set by operating the test mode switch by removing the cover, the light receiving device is configured to perform a test by changing an operation condition of its internal circuit. In the alarm device, the light receiving device is provided with means for terminating the test mode after a predetermined time elapses after the test mode switch is set to the test mode and returning the operating condition of the internal circuit to the normal operating condition. Characteristic intrusion alarm device.