JPH0877473A - Photoelectric separation type smoke sensor - Google Patents

Abstract

PURPOSE: To automatically set an adjustment mode with a detection signal of the opening or closure of a cover and facilitate adjusting operation. CONSTITUTION: This smoke sensor is provided with a control means 50 which sets the adjustment mode with the opening detection signal from the cover opening/closure detecting means 36 of a photodetector and controls the respective parts of the photodetector so as to facilitate the adjusting operation. In the adjustment mode set state, a signal output inhibiting means 82 inhibits a fire signal and a fault signal from being outputted, a monitor display control means 83 performs blinking control over an LED as a monitor means at the position corresponding to a photodetection level, and an optical axis confirmation lamp control means 61 performs blinking control over an LED as an optical axis confirmation lamp display means 33; and a monitor period varying means 84 varies a monitor period as the light emission period of pulse light of a light transmitter 42 in its early stage, and a fire monitoring means 80 decides that sensitivity is set with a distance selection switch 37 through a sensitivity setting state decision means 75 and resets the adjustment mode with the closure detection signal from the cover opening/closure detecting means 36, thereby monitoring a fire.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photoelectric-separation type smoke sensor in which a smoke-transmitting light-transmitting device and a smoke-detecting device are separated from each other. Regarding smoke detectors.

[0002]

2. Description of the Related Art As a conventional photoelectric separation type smoke detector,
For example, when adjusting the optical axis and adjusting the amount of received light, the adjustment mode is set by operating a switch, and a measuring device such as a tester is connected to the light receiver to adjust the amount of light received while observing the amount of received light. is there. However, in this smoke detector, the measuring device is connected to the detector body that is usually installed at a high place,
It was difficult to adjust because it was adjusted while looking at the measuring instrument, which was dangerous. In addition, there is a problem that the work cannot be performed at all if the measuring instrument is forgotten.

In order to solve such a problem, there is a sensor equipped with a display lamp for displaying the amount of received light.
In this photoelectric separation type smoke sensor, as shown in FIGS.
As shown in, when adjusting the light receiver, first, the cover 100 is removed, and the optical axis provided on the side surface of the main body 101,
The changeover switch 102 provided with the light amount and monitoring position is set to the “optical axis” position, and the adjusting screw 103 is turned to adjust the optical axis. Next, the distance setting switch 104 is set according to the monitoring distance, and after the changeover switch 102 is set to the “light amount” position, the light amount adjusting knob 105 is turned.

Three lamps 106 for receiving the amount of received light are provided to indicate whether the amount of received light is insufficient, proper or excessive.
The light amount adjustment knob 105 is turned so that the appropriate lamp blinks. When the insufficient lamp blinks, the light amount adjustment knob 105 is turned to the increase side, and when the excessive lamp blinks, the light amount adjustment knob 105 is turned to the decrease side. When the adjustment of the optical axis and the amount of received light is completed, the changeover switch 102 is set to the “monitoring” position, the battery is removed, the cover is attached, and the set button 107 is continuously pressed from the outside of the cover 100 for a predetermined time to enter the monitoring state. I was trying to become.

In these conventional photoelectric separation type smoke detectors, a fire signal or an obstacle signal is generated by accidentally blocking the front surface of the light receiver by hand when adjusting the optical axis or adjusting the amount of received light. When the adjustment mode is set by a switch operation so as not to send the signal to the receiver 1, the output of the fire signal and the obstacle signal to the receiver is prohibited.

[0006]

However, in such a conventional photoelectric separation type smoke sensor, the optical axis adjustment is performed after the changeover switch is set to the "optical axis" position. After finishing, set the selector switch to the "light intensity" position,
When the light receiving amount is adjusted and the adjustment of the optical axis and the light receiving amount is completed, the changeover switch is set to the "monitor" position, so the operation of the changeover switch is complicated, and as a result, the adjustment work is inefficient. There was a problem.

If the adjustment mode is not set by the switch operation, the output of the fire signal and the trouble signal cannot be prohibited. Therefore, the front surface of the light receiver is erroneously blocked by the hand before the adjustment mode is set and the fire signal is output. There was a problem of outputting a failure signal. The present invention has been made in view of such a conventional problem, and outputs the fire signal and the failure signal by automatically setting the adjustment mode by the open detection signal from the cover opening / closing detection means. Prohibition, blinking the monitor display means and the optical axis confirmation display means, and changing the monitoring cycle to a faster cycle to create an adjustable state eliminates the complexity of operation and improves the efficiency of adjustment. The purpose is to improve.

[0008]

FIG. 1 is a diagram for explaining the principle of the present invention. First, the present invention is directed to a photoelectric separation-type smoke sensor that separately arranges a light transmitter 42 having a light emitting element 53 and a light receiver 1 having a light receiving element 54 and detects light attenuation due to smoke between them. In the light receiving device 1, an adjustment mode is set by an open detection signal from the cover opening / closing detection means 36 that detects the opening / closing of the front cover that is opened / closed for adjusting the optical axis and setting the sensitivity, and adjustment work is facilitated. A control means 50 for controlling each part of the light receiver is provided so as to do so.

Here, the control means 50 has a signal output inhibiting means 82 for inhibiting the output of the fire signal and the fault signal in the adjustment mode setting state. Further, the light receiver 1 is provided with monitor display means 38 including a plurality of LEDs, and the control means 50 controls the monitor display control means 83 for controlling the blinking of the LED which is the monitor means at the position corresponding to the light reception level in the adjustment mode setting state. Have.

Further, the optical receiver 1 is provided with an optical axis confirmation lamp display means 33 composed of an LED, and the control means 50 is an LED which is the optical axis confirmation lamp display means 33 in the adjustment mode setting state.
It has an optical axis confirmation lamp control means 61 for controlling blinking. Further, the light receiver 1 is provided with a light emission control means 48 for outputting to the light transmitter 42 a light emission control signal for controlling the monitoring cycle which is the light emission cycle of the pulsed light in the light transmitter 42, and the control means 50 is the adjustment mode. In the set state, the monitoring cycle changing means 8 for controlling the light emission control means 48 so as to change the monitoring cycle to an early cycle.
4

Furthermore, the light receiver 42 is provided with a distance selection switch 37 for setting the sensitivity according to the monitoring distance, and the control means 50 is a sensitivity setting state judgment means 75 for judging the setting state of the distance selection switch 37. A fire monitoring unit 80 which determines that the sensitivity is set by the distance selection switch 37 by the sensitivity setting determination unit 75, and cancels the adjustment mode by a closing detection signal from the cover opening / closing detection unit 36 to perform fire monitoring. Have.

According to the photoelectric separation type smoke detector of the present invention having such a configuration, the adjustment mode is automatically set by the open detection signal from the cover opening / closing detection means 36, and the adjustment work is facilitated. Each part of the light receiver 1 is adjusted so that That is, in the adjustment mode setting state, the output of the fire signal and the fault signal is prohibited, the monitor display means 38 is further displayed, and the optical axis confirmation display means 33 is displayed to further accelerate the monitoring cycle. Further, the sensitivity is set by the distance selection switch 37, and the adjustment mode is automatically released by the closing detection signal from the cover opening / closing detection means 36.
Fire surveillance is performed.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. 2 to 6 are views showing an embodiment of the present invention. FIG. 2 is an exploded perspective view of a photodetector of a photoelectric separation type smoke sensor according to an embodiment of the present invention. The light transmitter has the same structure except for the light emitting element, its associated circuit, and some of the components.

In FIG. 2, the photodetector 1 of the photoelectric separation type smoke detector is separated from the light transmitter and is disposed on the side wall near the ceiling so as to face it, and the casing is composed of a vertically long front cover 2 and a main body 3. It is configured. A window 2A made of a material such as polycarbonate that allows near-infrared light to pass therethrough but cuts visible light.
Is provided. In addition, the cover 2 is provided with respect to the main body 3 with a cover stop wire 4, a fixing bracket 5, and a cover stop bracket 6.
Is configured to be opened and closed in the vertical direction by means of
As shown in an exploded view, the optical axis / light receiving amount adjusting mechanism of the lens holder 7 is housed. Further, the mounting plate 8 is screwed to the side wall near the ceiling so that the mounting plate 8 has a locking piece 8A.
The main body 3 is locked to.

Next, the mechanism accommodated in the main body 3 will be described in detail. First, the base 9 of the optical axis / light receiving amount adjusting mechanism is formed of a metal fitting having an L-shaped side cross section.
Fixed horizontally. Below the base 9, a shield case 10, a printed board 11 on which circuit components for receiving light are mounted, a power supply board 12, and an insulating sheet 1 for the light receiving board.
3 is housed in a transparent circuit cover 14.

The base 9 has a fitting hole 9A into which an adjusting screw 20A for adjusting the horizontal direction of the lens holder 7 is fitted in the optical axis direction, the lens holder 7 and its supporting member 15.
A shaft hole 9B for horizontally rotatably supporting the lens holder 7 and a locking hole 9C for locking one end of the coil spring 16 for preventing the rattling of the lens holder 7 in the horizontal direction are formed.

A separator 17 is provided in the shaft hole 9B of the base 9.
It is attached by the attachment screw 18 of the separator 1
The reference numeral 7 is configured to fit vertically into the flange portions 9D and 9E of the base 9 so as not to rotate in the horizontal direction. The separator 17 is formed with a hole 17A through which one end of the coil spring 16 penetrates, a recess 17B for accommodating the body of the coil spring 16 and a shaft hole 17C.

The lens holder 7 is supported rotatably in a vertical direction with respect to a supporting member 15 having a U-shaped front cross section.
The support member 15 has the above-described mounting screw 18 as an axis,
The shaft hole 9 of the base 9 is inserted through the shaft hole 17C of the separator 17.
It is attached so as to be horizontally rotatable with respect to B. First, the horizontal rotation mechanism will be described. The support member 15 has a receiving screw 1 at a position deviated from the shaft hole 15A.
A locking hole 15B for locking 9A in the vertical direction is formed, and a screw thread is formed in this receiving screw 19A so that the above-mentioned horizontal adjusting screw 20A can be screwed in the optical axis direction. There is. Therefore, when the adjusting screw 20A is rotated, the support member 15 is horizontally rotated about the mounting screw 18.

A locking hole 15C for locking the other end of the coil spring 16 in the vertical direction and an adjusting screw 20B for adjusting the vertical direction of the lens holder 7 are fitted in the support member 15 in the optical axis direction. A fitting hole 15D is formed, and the lens holder 7 is supported by the support member 15 so as to be vertically rotatable about the screws 21 and 22. A coil spring 23 for preventing vertical play of the lens holder 7 is attached to the lens holder 7,
One end of this coil spring 23 is the locking hole 1 of the support member 15.
5E and the other end is locked to the locking piece 7A of the lens holder 7.

A receiving screw 19B is laterally attached to the side surface of the lens holder 7 at a position deviated from its rotation axis, and the receiving screw 19B has a receiving screw 19A.
Similarly, the thread is formed so that the above-mentioned vertical adjusting screw 20B is screwed in the optical axis direction. Therefore, when the adjusting screw 20B rotates, the lens holder 7 rotates in the direction perpendicular to the support member 15. The lens holder 7 is provided with an aiming hole 7B at the front upper right for viewing from an obliquely front side, and an aiming hole 7C is provided at the upper left front so as to be parallel to the optical axis direction.
A reflection mirror 7D for obliquely reflecting the field of view visible from the sight hole 7B is attached. 7E is a lens held by the lens holder 7.

A light receiving substrate 24 and a light receiving shield case 25 are fixed to the back side of the lens holder 7 with screws 26 and 27. On both sides of the lens holder 7, light-receiving amount adjustment knobs 2
8 and 29 are attached, and the light receiving amount adjusting knobs 28 and 29 are attached.
Adjusts the amount of received light by changing the photoelectric conversion voltage of the photoelectric conversion circuit. The received light amount adjustment knob 28 performs a rough adjustment, and the received light amount adjustment knob 29 performs a fine adjustment.

Next, FIG. 3 is a front view of the light receiver 1 with the cover 2 removed. In FIG. 3, 30 is the adjusting screw 20.
A is an optical axis adjusting knob, 31 is an optical axis adjusting knob of the adjusting screw 20B, and the optical axis adjusting knobs 30 and 31 have the adjusting screws 20A and 20B both attached in the optical axis direction. When the cover 2 is removed, it can be easily operated at a high place.

When the optical axis adjusting knob 30 of the horizontal adjusting screw 20A rotates counterclockwise, the lens holder 7 rotates leftward, and when the optical axis adjusting knob 30 rotates clockwise, the lens moves. The holder 7 rotates rightward. Also,
When the optical axis adjusting knob 31 of the vertical adjusting screw 20B rotates counterclockwise, the lens holder 7 rotates downward, and when the optical axis adjusting knob 31 rotates clockwise, the lens holder 7 rotates. Rotates upward.

The lens 7E is housed in the lens holder 7, and the lens holder 7 has the support member 1 as described above.
5 is rotatably supported in the vertical direction, and a support member 15
Is supported by the base 9 so as to be horizontally rotatable. A terminal nameplate 32 is attached to the front side of the circuit cover 14 below the separator 17 fixed to the base 9. The printed circuit board 11 is provided with an optical axis confirmation lamp 33 for confirming the optical axis. The optical axis confirmation lamp 33 is made of a red LED and blinks in the adjustment mode state to make it easier to see from the other side.

Further, the optical axis confirmation lamp 33 of the printed circuit board 11
Fire indicator light 3 consisting of LEDs on the left side of the
4 is provided, and on the right side of the optical axis confirmation lamp 33, there is provided a failure indicator lamp 35 including an LED that indicates a failure.
This optical axis confirmation lamp 33, fire indicator lamp 34, obstacle indicator lamp 35
Light emitted from the transparent circuit cover 14 and the terminal nameplate 32
It is output to the outside through the holes drilled in the corresponding places.

Further, a cover opening / closing detection switch 36 as a cover opening / closing detection means for detecting opening / closing of the cover 2 is provided on the lower surface of the circuit cover 14, and the cover opening / closing detection switch 36 is as shown in FIG. Consists of limit switches. When the cover 2 is opened, the cover opening / closing detection switch 36 is turned off, and when the cover 2 is closed, the cover opening / closing detection switch 36 is turned on.

Further, a distance selection switch 37 is provided on the lower surface of the circuit cover 14, and the sensitivity can be set to the specified sensitivity by setting it according to the monitoring distance. The distance selection switch 37 is a dip switch, and can be set to, for example, 5 m or more and less than 45 m, 45 m or more and less than 100 m, etc. by setting the switch. The position where nothing is set is the position for adjustment.

On the lower surface of the printed circuit board 11, six chip LEDs 38A to 38F as monitor display means are provided.
Are arranged along the left-right direction. Ie LED
38A to 38F are mounted on the printed circuit board 11 so as to face obliquely when viewed from the front. When the other side is seen through the collimation hole 7B during the adjustment of the optical axis, the LEDs 38A to 38F are mounted obliquely so that the light emission of the LEDs 38A to 38F can be easily seen.

These LEDs 38A to 38F are, in order from the left, two yellow LEDs 38A and 38B, two green LEDs 38C and 38D, and two red LEDs 38.
The LEDs 38A to 38F, which are constituted by E and 38F, are controlled so as to blink in the positions corresponding to the light receiving level in the adjustment mode state. Therefore, the LEDs 38A to 3
8F constitutes a light receiving level meter, and also LE of green
The photoelectric conversion voltage of the photoelectric conversion circuit is adjusted so that an appropriate value is displayed when D38C and 38D blink.

That is, while checking the LEDs 38A to 38F, the light receiving amount adjusting knobs 28 and 29 are turned so that one of the two green LEDs 38C and 38D blinks. Thus, the vicinity of the center of the appropriate value of the amount of received light is obtained and the range of the amount of received light is known. In addition, 39 is an insertion terminal part. Next, FIG. 5 is a block diagram of a light receiver and a light transmitter.

In FIG. 5, reference numeral 1 is the light receiver, and the light receiver 1 is connected to a light transmitter 42 via light transmitter control lines 40 and 41. In addition, the light receiver 1 includes a fire signal line 43,
It is connected to the receiver 46 via the common line 44 and the fault signal line 45. Reference numeral 47 denotes a constant voltage / current limiting circuit provided in the light receiver 1. The constant voltage / current limiting circuit 47 is supplied with power from the receiver 46, generates a constant voltage, and limits the power source to generate a constant voltage. Is supplied to each part.

Reference numeral 48 denotes a light emission control circuit as a light emission control means for controlling the light emission operation of the light transmitter 42. The light emission control circuit 48 is supplied with a constant voltage from a constant voltage / current limiting circuit 47 via a diode 49. In response to an instruction from the control unit 50, a light emission control signal is sent to the light transmitter 42 via the light transmitter control line 41. That is, the light emission control circuit 48 transmits a constant voltage supplied from the constant voltage current limiting circuit 47 as a light emission control signal consisting of power interruptions at regular intervals based on the control signal intermittently transmitted from the control unit 50. Output to the container 42. This light emission control signal regulates the monitoring cycle of the signal emitted from the light transmitter 42 in a pulsed manner, and the monitoring cycle is
In the steady monitoring state, it is set to about 3 seconds.

When the interval between the control signals intermittently sent from the control unit 50 becomes short, the interval at which the power supply to be the light emission control signal output from the light emission control circuit 48 is cut off becomes short, and as a result, the monitoring cycle also becomes short. . For example, if the interval between the control signals sent from the control unit 50 becomes 1 second, the monitoring cycle also becomes 1
Seconds, faster cycle. Reference numeral 51 denotes a light emission control detection circuit provided in the light transmitter 42.
Detects the light emission control signal from the light receiver 1 and operates the light emission drive circuit 52. That is, the light-emission control detection circuit 51 detects power-off at a constant interval which becomes a light-emission control signal from the light-emission control circuit 48, and operates the light-emission drive circuit 52 with negative logic.

Therefore, the light emitting element 53 composed of an LED
Is driven by the light emission drive circuit 52 and emits near-infrared light in a pulsed manner to the light receiving element 54 of the light receiver 1 through the lens. Reference numeral 55 denotes an optical axis confirmation lamp drive circuit provided in the light transmitter 42. The optical axis confirmation lamp drive circuit 55 detects a light emission control signal from the light emission control detection circuit 51 and the opening / closing of the cover of the light transmitter 42. It operates in response to an open detection signal (OFF signal) from the cover opening / closing detection switch 70 to drive the optical axis confirmation lamp 56 composed of an LED to blink it.

Reference numeral 37 denotes a distance selection switch which is a dip switch provided in the light receiver 1. The distance selection switch 37 sends a signal, which is set according to the monitoring distance at the time of adjustment, and which shows a specified sensitivity, via the sensitivity input circuit 57. Output to the control unit 50. The control unit 50 completes various adjustments, and outputs the light receiving output after closing the cover 2 and the initial value and the distance selection switch 3
A threshold value (fire determination level) is calculated based on the sensitivity setting by No. 7, and this is stored in the RAM 81 as a reference signal.

The control unit 50 compares this reference signal with the received light signal, and when the received light signal is smaller than the reference signal, it judges that there is a fire and outputs a fire signal to the fire signal output circuit 71.
Reference numeral 36 denotes the cover open / closed detection switch provided in the light receiver 1. The cover open / closed detection switch 36 outputs an open detection signal (OFF signal) when the cover 2 is opened, and closes when the cover 2 is closed. The detection signal (ON signal) is output to the control unit 50 via the cover opening / closing input circuit 58 and also to the oscillation circuit 59.

The oscillating circuit 59 receives the open detection signal from the cover open / close detection switch 36 and the constant voltage from the constant voltage current limiting circuit 47 to generate a voltage of 5V. Based on the above, the oscillation operation is performed and the oscillation output is given to the optical axis confirmation lamp control circuit 61. The optical axis confirmation lamp control circuit 61 blinks the optical axis confirmation lamp 33 based on the oscillation output from the oscillation circuit 59 and the open detection signal from the cover opening / closing input circuit 58.

At the time of monitoring, when the control unit 50 detects a fire (for example, a dimming rate of 70% or more continues for a predetermined time),
The fire signal is sent to the receiver 46 by outputting to the fire signal output circuit 71. In this state, even if a failure due to interruption is detected (for example, a dimming rate of 90% or more continues for a predetermined time or longer), the control unit 50 detects a fire and does not output a failure signal. .

The fault signal output cutoff circuit 62 cuts the fault signal from the control unit 50 by the output from the fire signal detection circuit 71. Basically, the control unit 50
It is not necessary because the obstacle signal is not output, but it is provided in order to prevent the obstacle signal from being output to the receiver 46 even if it is erroneously output. The control unit 50 detects a failure due to interruption (for example, dimming rate 90
% Continues for a predetermined time or longer), the fault signal output circuit 63 outputs the fault signal to the receiver 46.

When a failure due to interruption is detected, or when it is detected that normal monitoring is not possible, a failure signal is output from the control unit 50, and the failure indicator lamp 35 flashes the occurrence of failure by this failure signal. Then, the fault signal output circuit 63 sends a fault signal to the receiver 46 via the fault signal line 45. On the other hand, when the fire signal output circuit 71 detects a fire signal from the control unit 50, the fire signal output circuit 71 turns on the fire indicating lamp 34 via the diode 64 and sends a fire signal to the receiver 46 via the fire signal line 43. .

Reference numeral 54 denotes the light receiving element formed of a photodiode provided in the light receiving device 1, and the light receiving element 54 receives the near infrared light emitted from the light emitting element 53 of the light transmitting device 42 in a pulsed manner. The light receiving element 54 and the variable resistor 72 form a photoelectric conversion circuit 65. The received light signal is the photoelectric conversion circuit 6
The signal is converted into an electric signal by 5 and is amplified by the amplifier circuit 66. By rotating the light receiving amount adjusting knobs 28 and 29, the resistance value of the variable resistor 72 is changed to change the photoelectric conversion voltage and increase or decrease the light receiving amount.

The analog electric signal amplified by the amplifier circuit 66 is held by the peak hold circuit 73 and then enters the control unit 50 through the light receiving amount input circuit 74. The control unit 50 is I
It is composed of C and has an A / D converter 68 built therein.
The analog electric signal is converted into a digital value by the A / D converter 68. The control unit 50 is provided with a drive table 69 for driving the LEDs 38A to 38F as the monitor display means, and the control unit 50 refers to the contents of the drive table 69 to drive the LEDs 38A to 38F, respectively.

Further, the control section 50 is provided with a sensitivity setting state judging section 75 as a sensitivity setting state judging means, and the sensitivity setting state judging section 75 serves as a distance selection switch 37 for setting the sensitivity according to the monitoring distance. Determine the setting status of the DIP switch. Further, the control unit 50 is provided with a cover open / closed state determination unit 76 as a cover open / closed state determination unit for determining the cover open / closed state depending on whether the cover open / close detection switch 36 for detecting the open / close state of the cover 2 is turned on or off. The determination unit 76 determines that the cover 2 is in the open state when the cover open / close detection switch 36 is off, and determines that the cover 2 is in the closed state when the cover open / close detection switch 36 is on.

Reference numeral 77 is a fault signal output unit as fault signal output means provided in the control unit 50. The fault signal output unit 77 outputs a fault signal when any of the following states is detected. (1) When it is detected that the cover 2 is closed without setting the sensitivity setting (when the sensitivity setting is forgotten during the adjustment).

(2) When it is detected that the cover 2 has been opened for a predetermined time T1 (for example, 5 minutes) or more with the sensitivity setting set (for the adjustment, the sensitivity was set but the cover was forgotten to be closed). If the cover comes off after some shock, such as when the ball hits). (3) When it is detected that the cover 2 has been opened for a predetermined time T2 (for example, 2 hours) or more in a state where the sensitivity is not set (the optical axis is adjusted but the sensitivity is set and the cover 2 is closed). If you just connect the power supply and did nothing later).

The fault signal is output to the fault signal output circuit 63 through the fault signal output cutoff circuit 62, transmitted from the fault signal output circuit 63 to the receiver 46, and the fault indicator lamp 35 blinks. An initial value registration unit 78 as an initial value registration unit is provided in the control unit 50, and the initial value registration unit 78 indicates that the sensitivity is set by the distance selection switch 37 by the sensitivity setting state determination unit 75. If it is determined that the cover open / closed state determination unit 76 determines the closed state of the cover 2 by the cover open / closed detection switch 36,
If the initial value is not registered, the received light output at that time is registered as the initial value.

That is, the initial value registration unit 78 registers the light reception output at that time as an initial value when the initial value is not registered in the RAM 81 at the time of start-up, power recovery after a power failure, etc. The registration of this initial value is performed by storing the received light output of multiple times, for example, five times (light emission and light reception are performed once every three seconds), calculating the average value, and setting the average value as the initial value. . This is because if one light reception output is set as the initial value, an incorrect light reception output (effect of noise or the like) is registered as the initial value.

If the averaged initial value is out of a certain set range, a fault signal is output and the initial value is registered again.
Further, the control unit 50 is provided with a fire judgment level calculation unit 79 as a fire judgment level calculation unit, and the fire judgment level calculation unit 79 is provided with the registered initial value and distance selection switch 37.
The threshold value (fire judgment level) is calculated from the sensitivity set in and the fire is monitored.

Further, the control unit 50 is provided with a fire monitoring unit 80 as a fire monitoring means, and when the initial value has already been registered, the fire monitoring unit 80 performs fire monitoring at the fire determination level that has already been calculated. I do. An initial value and a fire determination level are registered in the RAM 81 as a storage unit provided in the control unit 50. Even when the initial value and the fire judgment level stored due to a power failure or the like have disappeared, when the disappearance is detected, the initial value is registered again, the fire judgment level is calculated, and fire monitoring is performed. Further, when the control unit 50 receives the open detection signal from the cover open / close detection switch 36 as the cover open / close detection means, the control unit 50 automatically sets the adjustment mode.

Here, the control unit 50 is provided with a signal output inhibiting unit 82 as a signal output inhibiting unit, and the signal output inhibiting unit 82 is an open detection signal from the cover open / close detection switch 36 as a cover open / close detecting unit. Automatically enters the adjustment mode to prevent the fire signal and the obstacle signal from being output to the receiver 46. That is, when adjusting the optical axis and the amount of received light, first, the output of the fire signal and the obstacle signal is prohibited so that the optical axis and the amount of received light can be adjusted. In addition, the signal output prohibiting unit 82 causes the signal output prohibition unit 82 to output a closing detection signal from the cover opening / closing detection switch 36 after the adjustment work such as the adjustment of the optical axis and the amount of received light and the sensitivity setting by the distance selection switch 37 is completed.
Cancel the output prohibition of fire signals and obstacles.

Further, when the optical axis confirmation lamp control circuit 61 receives the open detection signal from the cover open / close detection switch 36 via the cover open / close input circuit 58, it automatically enters the adjustment mode and oscillates from the oscillation circuit 59. The output causes the optical axis confirmation lamp 33 as the optical axis confirmation lamp display means to blink. The blinking of the optical axis confirmation lamp 33 makes it easier for the other party to see when adjusting the optical axis.

Similarly, in the light transmitter 42, the optical axis confirmation lamp drive circuit 55 is operated by the open detection signal from the cover opening / closing detection switch 70, and the optical axis confirmation lamp 56 is made to blink.
Further, the control unit 50 is provided with a monitor display control unit 83 as a monitor display control means, and the monitor display control unit 83 automatically operates in response to an open detection signal from the cover open / close detection switch 36 via the cover open / close input circuit 58. Then, the adjustment mode is entered, and the LEDs 38A to 38F, which are the monitor display means at the position corresponding to the light receiving level, are blinked.

Blinking the LEDs 38A to 38F makes it easier to see the range of the amount of received light. The monitor display control unit 83 is operated by the closing detection signal from the cover opening / closing detection switch 36 after the adjustment is completed.
Turns off the LEDs 38A to 38F. Also, the control unit 5
0 indicates a monitoring cycle changing unit 84 as a monitoring cycle changing unit.
The monitoring cycle changing unit 84 automatically enters the adjustment mode in response to the open detection signal from the cover opening / closing detection switch 36 serving as the cover opening / closing detection means, changes the monitoring cycle to an early cycle, and detects the closing detection signal. A control signal for returning to the normal monitoring cycle is output to the light emission control circuit 48 as the light emission control means.

That is, the monitoring cycle changing section 84 outputs a control signal at an interval of 3 seconds to the light emission control circuit 48 during normal monitoring, and an open detection signal from the cover opening / closing detection switch 36 causes a control signal at an interval of 1 second. It outputs to the light emission control circuit 48, and outputs a normal control signal at intervals of 3 seconds to the light emission control circuit 48 according to the close detection signal. As a result, the emission control circuit 4
The reference numeral 8 outputs a light emission control signal to the light transmitter 42 which is normally turned off at intervals of 3 seconds, and a light emission control signal which is turned off at intervals of 1 second in the adjustment mode in which the cover 2 is open. Is output to the light transmitter 42, and when the cover 2 is closed, a normal light emission control signal at intervals of 3 seconds is output to the light transmitter 42.

As described above, when the cover 2 is open, the monitoring cycle is changed to an earlier cycle, so that there is no time lag between the adjustment and the signal change. Further, the fire monitoring unit 80 as a fire monitoring means operates via the cover opening / closing input circuit 58 from the cover opening / closing detection switch 36 after the adjustment work such as the adjustment of the optical axis, the amount of received light, and the sensitivity setting by the distance selection switch 37. Fire is monitored by the close detection signal.

Next, the operation will be described. FIG. 6 shows the control unit 50.
3 is a flowchart illustrating the operation of the above. In FIG. 6, first, in step S1, the cover opening / closing detection switch 36
Is determined to be off. When the cover open / close detection switch 36 is off, that is, when the cover 2 is open, the adjustment mode is automatically entered, and the fire signal and the trouble signal are not output in step 2.

That is, the signal output inhibiting unit 82 inhibits the output of the fire signal to the fire signal output circuit 71 and inhibits the output of the fault signal to the fault signal output circuit 63 via the fault signal output cutoff circuit 62. To do. next,
In step S3, any one of the LEDs 38A to 38F, which is the monitor display means, is blinked as the setting of the adjustment mode, the optical axis confirmation lamp 33 that is the optical axis confirmation lamp display means is blinked, and the monitoring cycle is set to an early cycle. change.

That is, by setting the adjustment mode by the open detection signal from the cover open / close detection switch 36, the monitor display control section 83 blinks the LEDs 38A to 38F, and the optical axis confirmation lamp control circuit 61 sets the optical axis. The confirmation lamp 33 blinks, and the monitoring cycle changing unit 84 outputs a control signal for speeding up the monitoring cycle to the light emission control circuit 48, thereby speeding up the cycle of the light emission control signal resulting from power interruption to speed up the monitoring cycle.

By making such a setting state of the adjustment mode, the adjustment work of the optical axis, the amount of received light, etc. is performed. It should be noted that it is desirable to output a fault signal to the receiver if adjustment is performed with the cover open and then it is forgotten to close the cover.
Therefore, for example, if the cover is not closed for about two hours after the cover is opened, it is preferable to judge that the cover has been forgotten to be closed, output a failure signal, and notify the person in charge.

When the adjustment work such as the adjustment of the optical axis and the amount of received light and the sensitivity setting by the distance selection switch 37 is completed in the adjustment mode setting state, it is then determined in step S4 whether the cover opening / closing detection switch 36 is on. When the cover open / close detection switch 36 is on, that is, when the cover 2 is closed, it is determined that the adjustment work has been completed, the adjustment mode is canceled, and in step S5, the signal output prohibiting unit 82 prohibits the output of the fire signal and the obstacle signal. To cancel. Further, the optical axis confirmation lamp control circuit 61 turns off the optical axis confirmation lamp 33, the monitor display control section 83 turns off the LEDs 38A to 38F, and the monitoring cycle changing section 84 returns the monitoring cycle to the original cycle.

Then, in step S6, the fire monitoring unit 80 performs fire monitoring. Even in the monitoring mode, ON / OFF of the cover opening / closing detection switch 36 is always monitored in step S7. When the cover opening / closing detection switch 36 is OFF, that is, when the open detection signal is returned to step S2, when ON, that is, when the closing detection signal is used, monitoring is continued. .

[0062]

As described above, according to the present invention, the adjustment mode is automatically set by the open detection signal from the cover opening / closing detection means, and each part of the light receiver is set so as to facilitate the adjustment work. Control. In this adjustment mode setting state, the output of the fire signal and the trouble signal is prohibited, the monitor display means is further displayed, and the optical axis confirmation lamp display means is displayed to further accelerate the monitoring cycle. Further, the sensitivity is set by the distance selection switch, and the adjustment mode is released by the closing detection signal from the cover opening / closing detection means, and then the fire monitoring state can be automatically entered.

[Brief description of drawings]

FIG. 1 is an explanatory view of the principle of the present invention.

FIG. 2 is an exploded perspective view of a light receiver showing an embodiment of the present invention.

FIG. 3 is a front view of the light receiver.

FIG. 4 is a side view of the light receiver.

FIG. 5 is a block diagram of a light receiver and a light transmitter.

FIG. 6 is a flowchart illustrating the operation.

FIG. 7 is a side view showing a conventional example.

FIG. 8 is a front view showing a conventional example.

[Explanation of symbols]

1: Light receiver 2: Cover 2A: Window 3: Main body 4: Cover fixing wire 5: Fixing metal 6: Cover fixing metal 7: Lens holder 7A: Locking piece 7B, 7C: Aiming hole 7D: Reflecting mirror 7E: Lens 8 : Mounting plate 8A: Locking piece 9: Base 9A: Fitting hole 9B: Shaft hole 9C: Locking hole 9D, 9E: Flange portion 10: Shield case 11: Printed circuit board 12: Power supply board 13: Insulation sheet for light receiving board 14: Circuit cover 15: Support member 15A: Shaft hole 15B, 15C, 15E: Locking hole 15D: Fitting hole 16, 23: Coil spring 17: Separator 17A: Hole 17B: Recess 17C: Shaft hole 18: Mounting screw 19A , 19B: Receiving screw 20A, 20B: Adjusting screw 21, 22, 26, 27: Screw 24: Light receiving substrate 25: Light receiving shield case 28, 29: Light receiving amount Adjustment knobs 30, 31: Optical axis adjustment knob 32: Terminal name plate 33, 56: Optical axis confirmation lamp (optical axis confirmation lamp display means) 34: Fire indicator lamp 35: Fault indicator lamp 36, 70: Cover open / close detection switch (cover Opening / closing detection means) 37: Distance selection switch 38: Monitor display means 38A to 38F: LED 39: Plug-in terminal portion 40, 41: Light transmitter control line 42: Light transmitter 43: Fire signal line 44: Common line 45: Fault Signal line 46: Receiver 47: Constant voltage current limiting circuit 48: Generation control circuit (light emission control means) 49, 64: Diode 50: Control unit 51: Light emission control detection circuit 52: Light emission drive circuit 53: Light emitting element 54: Light reception Element 55: Optical axis confirmation lamp drive circuit 57: Sensitivity input circuit 58: Cover open / close input circuit 59: Oscillation circuit 60: 5V constant voltage circuit 61: Optical axis confirmation lamp control circuit (optical Confirmation light control means) 62: Fault signal output cutoff circuit 63: Fault signal output circuit 65: Photoelectric conversion circuit 66: Amplification circuit 68: A / D converter 69: Driving table 71: Fire signal output circuit 72: Variable resistance 73: Peak hold circuit 74: Received light amount input circuit 75: Sensitivity setting state determination unit (sensitivity setting state determination unit) 76: Cover open / closed state determination unit 77: Fault signal output unit 78: Initial value registration unit 79: Fire determination level calculation unit 80 : Fire monitoring section (fire monitoring means) 81: RAM 82: Signal output prohibiting section (signal output prohibiting means) 83: Monitor display control section (monitor display control means) 84: Monitoring cycle changing section (monitoring cycle changing means)

Claims (6)

[Claims] 1. A photoelectric-separated smoke sensor, wherein a light-transmitting device having a light-emitting element and a light-receiving device having a light-receiving element are separately arranged, and light attenuation due to smoke between them is detected. In addition, the open mode detection signal from the cover open / close detection unit that detects the open / close state of the front cover that is opened / closed to adjust the optical axis and set the sensitivity is used to set the adjustment mode to facilitate the adjustment work. 2. A photoelectric-separated type smoke detector, characterized by comprising control means for controlling each part of the. 2. The photoelectric separation type smoke detector according to claim 1, wherein said control means has signal output prohibiting means for prohibiting output of a fire signal and a trouble signal in said adjustment mode setting state. Photoelectric separation type smoke detector characterized in that. 3. The photoelectric separation type smoke detector according to claim 1 or 2, wherein the light receiver is provided with a monitor display means composed of a plurality of LEDs, and the control means is in the adjustment mode setting state. A photoelectric separation-type smoke detector characterized in that it has a monitor display control means for controlling blinking of an LED as a monitor means at a position corresponding to a light receiving level. 4. The photoelectric separation type smoke sensor according to claim 1, wherein the light receiver is provided with an optical axis confirmation lamp display means composed of an LED, and the control means sets the adjustment mode setting state. 2. A photoelectric separated smoke detector, comprising: an optical axis confirmation lamp control means for controlling blinking of an LED which is an optical axis confirmation display means. 5. The photoelectric separated smoke detector according to claim 1, wherein the light receiver is provided with a light emission control signal for controlling a monitoring period which is a light emission period of the pulsed light in the light transmitter. A light emission control means for outputting to the light transmitter is provided, and the control means has a monitoring cycle changing means for controlling the light emission control means so as to change the monitoring cycle to an early cycle in the adjustment mode setting state. The feature is a photoelectric separated smoke detector. 6. The photoelectric separation type smoke detector according to claim 1, wherein the light receiving device is provided with a distance selection switch for setting sensitivity according to a monitoring distance, and the control means sets the distance. Sensitivity setting state determining means for determining the setting state of the selection switch, determining that the sensitivity is set by the distance selection switch by the sensitivity setting determining means, and detecting a closing detection signal from the cover opening / closing detection means. A photoelectric-separated smoke detector, comprising: fire monitoring means for releasing the adjustment mode and performing fire monitoring.