JP2892303B2 - Photoelectric separated smoke 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 photoelectric separation type smoke detector in which a light transmitter and a receiver for smoke detection are separated, and more particularly to a photoelectric separation type smoke detector for efficiently adjusting the optical axis and the amount of received light. Related to smoke detectors.

[0002]

2. Description of the Related Art Conventional photoelectric separation type smoke detectors include:
For example, the adjustment of the optical axis and the amount of received light is performed by setting the adjustment mode by operating the switch, connecting a measuring instrument such as a tester to the receiver, and adjusting the received light amount so as to obtain the appropriate amount of received light. is there. However, in this smoke detector, a measuring instrument is connected to the sensor body which is usually mounted at a high place,
The adjustment was difficult while looking at the measuring instrument, which was difficult and dangerous. In addition, there is a problem that work cannot be performed at all if the measuring instrument is forgotten.

[0003] In order to solve such a problem, there is a sensor equipped with a display lamp for displaying the amount of received light in the sensor itself.
In this photoelectric separation type smoke detector, FIGS.
As shown in (1), 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 having the light amount and the monitoring position is set to the “optical axis” position, and the adjustment 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 adjustment knob 105 is turned.

[0004] Three received light amount display lamps 106 are provided, which respectively indicate insufficient, appropriate, and excessive amounts of received light.
Turn the light amount adjustment knob 105 to make adjustment so that an appropriate lamp blinks. When the insufficient lamp blinks, the light amount adjustment knob 105 is turned upward, and when the excessive lamp blinks, the light amount adjustment knob 105 is turned downward. After 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 be.

[0005] In these conventional photoelectric-separated smoke detectors, when adjusting the optical axis and the amount of received light, the front of the receiver is erroneously blocked by hand or the like. In order to prevent the fire signal and the failure signal from being transmitted to the receiver 1, when the adjustment mode is set by the switch operation, the output of the fire signal and the failure signal to the receiver is prohibited.

[0006]

However, in such a conventional photoelectric separation type smoke sensor, the optical axis is adjusted after the changeover switch is set to the "optical axis" position, and the optical axis adjustment is performed. After completion, set the changeover switch to the “light amount” position,
The adjustment of the received light amount is performed, and after the adjustment of the optical axis and the received light amount is completed, the changeover switch is set to the “monitoring” position, so that the operation of the changeover switch is complicated, and as a result, the efficiency of the adjustment work is poor. There was a problem.

In addition, since the output of the fire signal and the failure signal cannot be prohibited unless the adjustment mode is set by operating the switch, the front of the light receiver is erroneously blocked by hand before the adjustment mode is set, and the fire signal is output. And output a failure signal. The present invention has been made in view of such a conventional problem, and automatically sets an adjustment mode based on an open detection signal from a cover open / close detection unit, thereby outputting the fire signal and the failure signal. By prohibiting, furthermore, by blinking the monitor display means and the optical axis confirmation display means, and by changing the monitoring cycle to an earlier cycle to create an adjustable state, the operation is simplified and the efficiency of adjustment is reduced. The purpose is to improve.

[0008]

FIG. 1 is a diagram illustrating the principle of the present invention. First, the present invention is directed to a photoelectric separation type smoke sensor in which a light transmitter 42 having a light emitting element 53 and a light receiver 1 having a light receiving element 54 are arranged separately, and a light attenuation due to smoke is detected therebetween. An adjustment mode is set in the light receiver 1 by an opening detection signal from a cover opening / closing detecting means 36 which detects opening / closing of a front cover which is opened / closed for adjustment of an optical axis or the like and sensitivity setting, thereby facilitating adjustment work. A control means 50 for controlling each part of the light receiver is provided.

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

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

Further, 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 includes a sensitivity setting state determination means 75 for determining the setting state of the distance selection switch 37; The sensitivity setting discriminating means 75 discriminates that the sensitivity is set by the distance selection switch 37, and cancels the adjustment mode by the close detection signal from the cover open / close detecting means 36, and monitors the fire by the fire monitoring means 80. Having.

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 open / close detection means 36, and the adjustment work can be easily performed. Each part of the light receiver 1 is adjusted so as to perform. That is, in the adjustment mode setting state, the output of the fire signal and the failure signal is prohibited, the monitor display means 38 is displayed, the optical axis confirmation display means 33 is displayed, and the monitoring cycle is further shortened. Further, the sensitivity is set by the distance selection switch 37, and the adjustment mode is automatically released by the close detection signal from the cover open / close detection means 36.
Fire monitoring is performed.

[0013]

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 light receiver of the photoelectric separation type smoke detector according to one embodiment of the present invention. The light transmitter has the same configuration except for a part of the light emitting element, its related circuit, and components.

In FIG. 2, a photodetector 1 of a photoelectric separation type smoke detector is disposed on a side wall near a ceiling so as to be opposed to a light transmitter, and a housing is composed of a vertically long front cover 2 and a main body 3. It is configured. The cover 2 allows near infrared light to pass therethrough but cuts visible light, for example, a window 2A made of polycarbonate.
Is provided. The cover 2 is attached to the main body 3 by a cover fixing wire 4, a fixing member 5, and a cover fixing member 6.
Is configured to be openable and closable in the vertical direction.
As shown in an exploded manner, an 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, and the locking piece 8A of the mounting plate 8 is fixed.
The main body 3 is locked.

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

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

The shaft hole 9B of the base 9 has a separator 17
And the separator 1
Reference numeral 7 is configured to fit vertically to the flange portions 9D and 9E of the base 9 so as not to rotate in the horizontal direction. The separator 17 has a hole 17A through which one end of the coil spring 16 passes, a concave portion 17B for accommodating the coil spring 16 body, a shaft hole 17C, and the like.

The lens holder 7 is supported rotatably in the vertical direction with respect to a support member 15 having a U-shaped front section.
The support member 15 has the mounting screw 18 described above as an axis,
The shaft hole 9 of the base 9 is inserted through the shaft hole 17C of the separator 17.
B is attached to be rotatable in the horizontal direction. 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 the 9A in the vertical direction is formed, and a thread is formed in the receiving screw 19A so that the above-described horizontal adjustment screw 20A is screwed in the optical axis direction. I have. Therefore, when the adjustment screw 20A rotates, the support member 15 rotates in the horizontal direction around 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 supporting member 15 in the optical axis direction. The lens holder 7 is supported so as to be rotatable in the vertical direction about the screws 21 and 22 with respect to the support member 15. A coil spring 23 for preventing the vertical play of the lens holder 7 is attached to the lens holder 7.
One end of the coil spring 23 has the locking hole 1 of the support member 15.
5E, and the other end is locked to a locking piece 7A of the lens holder 7.

A receiving screw 19B is mounted on the side surface of the lens holder 7 at a position deviated from the rotation axis in the left-right direction. The receiving screw 19B is attached to the receiving screw 19B.
Similarly to the above, a screw thread is formed so that the above-described vertical adjustment screw 20B is screwed in the optical axis direction. Therefore, when the adjustment screw 20 </ b> B rotates, the lens holder 7 rotates in a direction perpendicular to the support member 15. The lens holder 7 is provided with an aiming hole 7B for observing from obliquely forward and on the upper right of the front, and an aiming hole 7C is provided on the upper left of the front so as to be parallel to the optical axis direction.
A reflection mirror 7D for obliquely reflecting the visual field seen from the sighting hole 7B is attached. Reference numeral 7E denotes a lens held by the lens holder 7.

On the back side of the lens holder 7, a light receiving substrate 24 and a light receiving shield case 25 are fixed by screws 26 and 27. On both sides of the lens holder 7, light receiving amount adjusting knobs 2
8 and 29 are attached, and light reception amount adjustment knobs 28 and 29 are provided.
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 coarse adjustment, and the received light amount adjustment knob 29 performs fine adjustment.

FIG. 3 is a front view of the light receiver 1 with the cover 2 removed. In FIG. 3, reference numeral 30 denotes the adjusting screw 20.
The optical axis adjustment knobs A and 31 are the optical axis adjustment knobs for the adjustment screw 20B, and the optical axis adjustment knobs 30 and 31 face the front because the adjustment screws 20A and 20B are both mounted in the optical axis direction. When the cover 2 is removed, it can be easily operated at a high place.

When the optical axis adjustment knob 30 of the horizontal adjustment screw 20A is rotated counterclockwise, the lens holder 7 is rotated to the left, and when the optical axis adjustment knob 30 is rotated clockwise, the lens is rotated. The holder 7 rotates rightward. Also,
When the optical axis adjustment knob 31 of the vertical adjustment screw 20B rotates counterclockwise, the lens holder 7 rotates downward, and when the optical axis adjustment 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 holds the support member 1 as described above.
5 so as to be rotatable in the vertical direction.
Is rotatably supported by the base 9 in the horizontal direction. 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 light 33 for confirming the optical axis. The optical axis confirmation light 33 is made up of a red LED and blinks in the adjustment mode to make it easier to see from the other party.

Further, the optical axis checking lamp 33 on the printed circuit board 11
On the left side of the display is a fire indicator light 3 consisting of an LED that indicates a fire.
4 is provided, and on the right side of the optical axis confirmation light 33, a failure indicator light 35 composed of an LED for displaying a failure is provided.
The optical axis confirmation light 33, the fire indicator light 34, and the fault indicator light 35
From the transparent circuit cover 14 and the terminal nameplate 32
Is output to the outside through a hole opened in the corresponding place.

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

A distance selection switch 37 is provided on the lower surface of the circuit cover 14, and can be set to a 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 to less than 45 m or 45 m or more to less than 100 m by setting the switch. The position where nothing is set is a 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. That is, 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 party is looked through the collimation hole 7B during the optical axis adjustment, the LED 38A to 38F is mounted obliquely so that the light emission of the LEDs 38A to 38F can be easily viewed from the viewing direction.

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

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 received light amount is obtained, and the range of the received light amount 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 denotes the light receiver, and the light receiver 1 is connected to a light transmitter 42 via light transmitter control lines 40 and 41. The light receiver 1 is provided with a fire signal line 43,
It is connected to a receiver 46 via a common line 44 and a fault signal line 45. Reference numeral 47 denotes a constant voltage / current limiting circuit provided in the photodetector 1. The constant voltage / current limiting circuit 47 receives a power supply from the receiver 46, generates a constant voltage, and limits the power supply. Is supplied to each part.

Reference numeral 48 denotes a light emission control circuit as light emission control means for controlling the light emission operation of the light transmitter 42. The light emission control circuit 48 receives a constant voltage from a constant voltage current limiting circuit 47 via a diode 49, and The light emission control signal is transmitted to the light transmitter 42 via the light transmitter control line 41 in accordance with an instruction from the controller 50. 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 having a constant interval of power-off based on a control signal intermittently sent from the control unit 50. Output to the unit 42. This light emission control signal regulates a monitoring cycle of a signal emitted from the light transmitter 42 in a pulsed manner.
In the regular monitoring state, it is set to about 3 seconds.

When the interval between the control signals intermittently sent from the control unit 50 is shortened, the interval for turning off the power, which is the emission control signal output from the emission control circuit 48, is shortened, and as a result, the monitoring cycle is also shortened. . For example, if the interval between control signals sent from the control unit 50 is 1 second, the monitoring cycle is also 1 unit.
Seconds, the cycle is faster. 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 a power-off at regular intervals, which becomes a light emission control signal by 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 a light emission drive circuit 52 and emits near-infrared light to the light receiving element 54 of the light receiver 1 in a pulsed manner via a lens. Reference numeral 55 denotes an optical axis confirmation lamp driving circuit provided in the light transmitter 42. The optical axis confirmation lamp driving circuit 55 detects the light emission control signal from the light emission control detection circuit 51 and the opening / closing of the cover of the light transmitter 42. Activated by an open detection signal (off signal) from the cover open / close detection switch 70, the optical axis confirmation lamp 56 composed of an LED is driven and blinks.

Reference numeral 37 denotes a distance selection switch which is a dip switch provided in the light receiver 1. The distance selection switch 37 receives a signal which is set according to the monitoring distance at the time of adjustment and indicates a specified sensitivity via a sensitivity input circuit 57. And outputs it to the control unit 50. After various adjustments have been completed and the cover 50 has been closed, the control unit 50 controls the initial value, which is the light reception output, and the distance selection switch 3.
A threshold value (fire judgment level) is calculated based on the sensitivity setting made by 7 and stored in the RAM 81 as a reference signal.

The control unit 50 compares the reference signal with the received light signal. If the received light signal is smaller than the reference signal, it determines that a fire has occurred, and outputs a fire signal to the fire signal output circuit 71.
Reference numeral 36 denotes the cover open / close detection switch provided in the photodetector 1. The cover open / close 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 is also output 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 supplied from the constant voltage current limiting circuit 47 to generate a 5V voltage. Oscillating operation is performed based on the above, and an oscillating output is given to the optical axis checking lamp control circuit 61. The optical axis confirmation light control circuit 61 blinks the optical axis confirmation light 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),
By outputting the signal to the fire signal output circuit 71, a fire signal is sent to the receiver 46. 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 more), the control unit 50 does not output a failure signal because a fire has been detected. .

The failure signal output cutoff circuit 62 cuts the failure signal from the control unit 50 based on the output from the fire signal detection circuit 71. Basically, the control unit 50 performs
This is not necessary because the failure signal is not output, but is provided so that the failure signal is not output to the receiver 46 even if it is output erroneously. The control unit 50 detects a failure due to the interruption (for example, the dimming rate 90
When% or more continues for a predetermined time or more), the failure signal is output to the failure signal output circuit 63, and the failure signal is sent to the receiver 46.

When a failure due to interruption is detected or when it is detected that normal monitoring cannot be performed, a failure signal is output from the control unit 50, and the failure signal causes the failure indicator light 35 to blink the occurrence of the failure. 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 detecting the fire signal from the control unit 50, the fire signal output circuit 71 turns on the fire indicator light 34 via the diode 64 and sends the fire signal to the receiver 46 via the fire signal line 43. .

Numeral 54 denotes the light receiving element formed of a photodiode provided in the light receiver 1. The light receiving element 54 receives near-infrared light emitted from the light emitting element 53 of the light transmitter 42 in a pulsed manner. The light receiving element 54 and the variable resistor 72 constitute a photoelectric conversion circuit 65. The light receiving signal is transmitted to the photoelectric conversion circuit 6
The signal is converted into an electric signal by the amplifier 5 and amplified by the amplifier circuit 66. By turning the light receiving amount adjustment 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 section 50 via the received light amount input circuit 74. The control unit 50
C, and incorporates an A / D converter 68.
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. The control unit 50 drives the LEDs 38A to 38F with reference to the contents of the drive table 69.

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

Reference numeral 77 denotes 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 in a state where the sensitivity setting is not set (at the time of adjustment, when the sensitivity setting is forgotten).

(2) When it is detected that the cover 2 has been opened for more than a predetermined time T1 (for example, 5 minutes) in a state where the sensitivity setting has been set (at the time of adjustment, the sensitivity was set but the cover was forgotten to be closed) If the cover comes off later due to 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) in a state where the sensitivity has not been set (the optical axis has been adjusted, but the user forgets to set the sensitivity or close the cover 2). If you just plug in the power and do nothing afterwards).

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 light 35 blinks. In the control unit 50, an initial value registration unit 78 as an initial value registration unit is provided. The initial value registration unit 78 confirms that the sensitivity is set by the distance selection switch 37 by the sensitivity setting state determination unit 75. When the cover open / closed state determination unit 76 determines that the cover 2 is closed by the cover open / close detection switch 36,
If the initial value has not been registered, the received light output at that time is registered as the initial value.

That is, the initial value registering unit 78 registers the initial value of the received light as the initial value when the initial value has not been registered in the RAM 81 at the time of start-up, power recovery after a power failure, etc. The registration of the initial value is performed by storing a plurality of, for example, five light receiving outputs (light emission and light receiving 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 receiving output is set as an initial value, an incorrect light receiving output (effect of noise or the like) is registered as an 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 operation unit 79 as a fire judgment level operation unit, and the fire judgment level operation unit 79 includes the registered initial value and the distance selection switch 37.
Calculates the threshold value (fire judgment level) from the sensitivity set in, and performs fire monitoring.

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

Here, the control section 50 is provided with a signal output prohibiting section 82 as signal output prohibiting means, and the signal output prohibiting section 82 is provided with an open detection signal from the cover open / close detection switch 36 as cover open / close detection means. Automatically enters the adjustment mode so that the fire signal and the fault signal are not output to the receiver 46. That is, when adjusting the optical axis and the received light amount, first, the output of the fire signal and the failure signal is prohibited, and the optical axis and the received light amount can be adjusted. In addition, the signal output prohibition unit 82 is controlled by the close detection signal from the cover open / close 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 is completed.
Release the output prohibition of fire signal and obstacle.

When the optical axis confirming light 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 the oscillation circuit 59 oscillates. By the output, the optical axis confirmation lamp 33 as the optical axis confirmation lamp display means is flickered. The flickering of the optical axis confirmation lamp 33 makes it easy to see from the partner side when adjusting the optical axis.

Similarly, in the light transmitter 42, the optical axis confirmation lamp driving circuit 55 is operated by the open detection signal from the cover open / close detection switch 70, and the optical axis confirmation lamp 56 is turned on and off.
Further, the control unit 50 is provided with a monitor display control unit 83 as a monitor display control unit. The monitor display control unit 83 automatically responds to an open detection signal from the cover open / close detection switch 36 via the cover open / close input circuit 58. 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, blink.

The blinking of the LEDs 38A to 38F makes it easier to see the range of the amount of received light. The monitor display control unit 83 receives a close detection signal from the cover open / close detection switch 36 after the adjustment is completed.
Turns off the LEDs 38A to 38F. 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 an open detection signal from the cover opening / closing detection switch 36 as a cover opening / closing detection unit, changes the monitoring cycle to a shorter cycle, and responds to the closing detection signal. A control signal for returning to the normal monitoring cycle is output to a light emission control circuit 48 as light emission control means.

That is, the monitoring cycle changing section 84 outputs a control signal at three-second intervals to the light emission control circuit 48 during normal monitoring, and outputs a control signal at one-second intervals based on the open detection signal from the cover open / close detection switch 36. The control signal is output to the light emission control circuit 48, and a control signal at regular three-second intervals is output to the light emission control circuit 48 based on the close detection signal. Thereby, the light emission control circuit 4
Reference numeral 8 denotes a light emission control signal output from the power transmitter at normal intervals of 3 seconds to the transmitter 42, and a light emission control signal output from power supply at 1 second intervals 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, the light emission control signal is output to the light transmitter 42 at regular three-second intervals.

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

Next, the operation will be described. FIG.
5 is a flowchart for explaining the operation of FIG. In FIG. 6, first, in step S1, the cover open / close detection switch 36
It is determined whether or not is off. When the cover open / close detection switch 36 is off, that is, when the cover 2 is open, the control automatically enters the adjustment mode, and in step 2, the fire signal and the failure signal are not output.

That is, the signal output prohibiting section 82 prohibits the output of the fire signal to the fire signal output circuit 71 and the output of the fault signal to the fault signal output circuit 63 via the fault signal output cutoff circuit 62. I do. next,
In step S3, one of the LEDs 38A to 38F as the monitor display means is flickered as the setting of the adjustment mode, and the optical axis confirmation light 33 as the optical axis confirmation light display means is flickered. change.

That is, by setting the adjustment mode based on the open detection signal from the cover open / close detection switch 36, the monitor display control unit 83 causes the LEDs 38A to 38F to blink, and the optical axis confirmation light control circuit 61 activates the optical axis confirmation light control circuit 61. The confirmation light 33 is turned on and off, and the monitoring cycle changing unit 84 outputs a control signal for shortening the monitoring cycle to the light emission control circuit 48, thereby shortening the cycle of the light emission control signal resulting from the power-off, thereby shortening the monitoring cycle.

The setting state of such an adjustment mode is created, and the adjustment work of the optical axis, the amount of received light, and the like is performed. If adjustment is performed with the cover open and the user forgets to close the cover after that, it is desirable to output a failure signal to the receiver.
Therefore, if the cover is not closed for about two hours after the cover is opened, it is preferable to judge that the user has forgotten to close the cover and output a failure signal to inform 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 next determined in step S4 whether the cover open / close 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 operation has been completed, the adjustment mode is released, and the output of the fire signal and the failure signal by the signal output inhibition unit 82 is inhibited in step S5. Cancel. Further, the optical axis confirmation lamp control circuit 61 turns off the optical axis confirmation lamp 33, the monitor display control unit 83 extinguishes the LEDs 38A to 38F, and the monitoring cycle changing unit 84 returns the monitoring cycle to the original cycle.

Then, the process proceeds to a step S6, where the fire monitoring unit 80 monitors the fire. Even in the monitoring mode, the on / off state of the cover open / close detection switch 36 is constantly monitored in step S7. When the cover is off, that is, the operation returns to step S2 according to the open detection signal, and when it is on, that is, the monitoring is continued based on the close detection signal. .

[0062]

As described above, according to the present invention, the adjustment mode is automatically set according to the open detection signal from the cover open / close 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 failure signal is prohibited, the monitor display means is displayed, the optical axis confirmation light display means is displayed, and the monitoring cycle is further shortened. In addition, the sensitivity is set by the distance selection switch, and the adjustment mode is released by the close detection signal from the cover open / close detection means. Thereafter, the state can be automatically shifted to the fire monitoring state.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating the principle of the present invention.

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

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

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

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

FIG. 6 is a flowchart illustrating an 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: Receiver 2: Cover 2A: Window 3: Main body 4: Cover fixing wire 5: Fixing bracket 6: Cover fixing bracket 7: Lens holder 7A: Locking piece 7B, 7C: Aiming hole 7D: Reflection mirror 7E: Lens 8 : Mounting plate 8A: Locking piece 9: Base 9A: Fitting hole 9B: Shaft hole 9C: Locking hole 9D, 9E: Flange section 10: Shield case 11: Printed circuit board 12: Power supply board 13: Insulating 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 board 25: Light receiving shield case 28, 29: Light receiving amount Adjusting knobs 30, 31: Optical axis adjusting knob 32: Terminal nameplate 33, 56: Optical axis confirmation light (optical axis confirmation light display means) 34: Fire indicator light 35: Fault indicator light 36, 70: Cover open / close detection switch (cover) Open / close detection means) 37: distance selection switch 38: monitor display means 38A to 38F: LED 39: insertion terminal section 40, 41: light transmitter control line 42: light transmitter 43: fire signal line 44: common line 45: failure 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 emission element 54: Light reception Element 55: Optical axis confirmation light driving circuit 57: Sensitivity input circuit 58: Cover opening / closing input circuit 59: Oscillation circuit 60: 5V constant voltage circuit 61: Optical axis confirmation light control circuit (optical Confirmation light control means) 62: fault signal output cutoff circuit 63: fault signal output circuit 65: photoelectric conversion circuit 66: amplifier circuit 68: A / D converter 69: drive table 71: fire signal output circuit 72: variable resistor 73: Peak hold circuit 74: Light reception amount input circuit 75: Sensitivity setting state determination unit (sensitivity setting state determination unit) 76: Cover open / closed state determination unit 77: Failure signal output unit 78: Initial value registration unit 79: Fire determination level calculation unit 80 : Fire monitoring unit (fire monitoring unit) 81: RAM 82: Signal output prohibition unit (signal output prohibition unit) 83: Monitor display control unit (monitor display control unit) 84: Monitoring cycle change unit (monitoring cycle change unit)

Claims (6)

(57) [Claims] 1. A photoelectric separation type smoke detector for separately arranging a light transmitter having a light emitting element and a light receiver having a light receiving element and detecting attenuation of light caused by smoke therebetween. An adjustment mode is set by an open detection signal from a cover open / close detection unit that detects the opening / closing of a front cover that opens and closes to adjust the optical axis and set the sensitivity. And a control means for controlling each part of the photoelectric separation type smoke detector. 2. The photoelectric separation type smoke detector according to claim 1, wherein said control means has signal output prohibition means for prohibiting output of a fire signal and a failure signal in said adjustment mode setting state. A photoelectric separation type smoke detector characterized by the above-mentioned. 3. The photoelectric separation type smoke detector according to claim 1, wherein said light receiver is provided with a monitor display means comprising a plurality of LEDs, and said control means is configured to control said light-receiving device in said adjustment mode setting state. And a monitor display control means for controlling blinking of an LED which is a monitor means at a position corresponding to a light receiving level. 4. In the photoelectric separated smoke sensor according to any one of claims 1 to 3, the light receiver is provided an optical axis indication lamp display unit consisting of LED, the control means, wherein In the adjustment mode setting state, the optical axis confirmation display means L
A photoelectric-separated smoke detector having an optical axis confirmation light control means for controlling blinking of an ED. 5. In the photoelectric separated smoke sensor according to any one of claims 1 to 4, the light receiver, for controlling the monitoring period is a light-emitting period of the pulsed light in the light transmission device A light emission control means for outputting a light emission control signal to the light transmitter, wherein the control means controls the light emission control means to change the monitoring cycle to a shorter cycle in the adjustment mode setting state; A photoelectric type smoke detector characterized by having: 6. In the photoelectric separated smoke sensor according to any one of claims 1 to 5, the light receiver, provided the distance selection switch for setting the sensitivity in accordance with the monitoring distance, said control means A sensitivity setting state determining means for determining a setting state of the distance selection switch; a sensitivity setting determining means for determining that sensitivity is set by the distance selection switch; and And a fire monitoring means for canceling the adjustment mode by a close detection signal and monitoring a fire.