JP2013073591A - Photoelectric separation-type smoke sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photoelectric separation-type smoke sensor for reducing an influence of external rays of light.SOLUTION: A photoelectric separation-type smoke sensor includes: a light transmission part 20 for transmitting the rays of light; and a light reception part 10 for receiving the rays of light transmitted by the light transmission part 20. The light transmission part includes a light transmission filter 21 for polarizing the rays of light, and the light reception part includes a light reception filter 11 for polarizing the rays of light to be received by the light reception part. The polarizing direction of the light transmission filter is changed, or the polarizing direction of the light reception filter is changed so that an angular difference between the polarizing direction of the light transmission filter and the polarizing direction of the light reception filter can be controlled, and that an operation test and a non-operation test can be performed. Therefore, it is possible to perform the operation test and the non-operation test on the basis of an operation from the outside or a test signal input. Also, since the light reception filter is arranged, only the polarized rays of light in a specific direction among external rays of light including polarized rays of light in various directions can pass. Thus, it is possible to reduce an influence of the external rays of light.

Description

  The present invention relates to a photoelectric separation type smoke detector.

Conventionally, there are smoke detectors that use light to monitor long-distance spaces at relatively high places such as gymnasiums, factories, and atriums.
As such a smoke detector, for example, a light emitting unit (light transmitting unit) and a light receiving unit are installed separately, and the presence or absence of smoke is detected by the light receiving unit receiving the light emitted from the light emitting unit, A photoelectric separation type smoke detector for detecting the occurrence of a fire is known (see Patent Document 1).

  Conventionally, when performing an operation test / non-operation test of the photoelectric separation type smoke detector, a filter having an iron plate in a lattice shape is placed on the optical path of the photoelectric separation type smoke detector for a predetermined time (for example, 30 seconds). It was inserted above. As an operation test, as a simulation test of the operation of the photoelectric separation type smoke detector when light is blocked by smoke, it has been confirmed that a fire is detected by inserting a filter having a small grid interval. In addition, as a non-operation test, the grid separation is large as a simulation test that the photoelectric separation type smoke detector does not operate even when the light intensity is reduced by dust or the like when the reduction rate is below a predetermined value. It was confirmed that a fire was not detected by inserting a filter. In other words, the operation test and the non-operation test were performed by reducing the light intensity with a grid-like filter.

JP 2003-16546 A

  However, in the conventional photoelectric separation type smoke detector, not only the light emitted from the light transmitting unit but also external light and its reflected light may enter the light receiving unit. Therefore, there is a problem that if the amount of the external light and the reflected light is large, the light receiving element is saturated and it is difficult to detect smoke.

  In addition, since the photoelectric separation type smoke detector is installed at a high place, when performing an operation test / non-operation test, a scaffolding is assembled, or a stretching device having a heavy weight on a lattice filter is attached. It was necessary to insert a grid-like filter on the optical path. Therefore, there is a problem that it is difficult to perform the test.

  The present invention has been made to solve the above-described problems, and provides a photoelectric separation type smoke detector that can reduce the influence of external light.

  The photoelectric separation-type smoke detector of the present invention is a photoelectric separation-type smoke detector comprising: a light transmission unit that emits light; and a light reception unit that receives light emitted from the light transmission unit. Has a light receiving filter for polarizing the light received by the light receiving section.

  In the photoelectric separation type smoke detector of the present invention, the polarization direction of the light receiving filter can be changed.

  The photoelectric separation type smoke detector of the present invention further includes a control unit that controls the polarization direction of the light receiving filter so that the intensity of the external light received by the light receiving unit falls within a predetermined range from the minimum value. It is.

  The photoelectric separation type smoke detector of the present invention has a light transmission filter for polarizing light in the light transmission section.

  The photoelectric separation type smoke detector of the present invention includes a light transmitting element that emits light and a light transmission filter that polarizes light emitted from the light transmitting element in the light transmitting unit, and the light transmitting unit. By changing the polarization direction of the filter, an operation test and a non-operation test are performed by controlling an angle difference between the polarization direction of the light transmission filter and the polarization direction of the light reception filter.

  In the photoelectric separated smoke detector of the present invention, the operation test and the non-operation test are performed by an external operation or a test signal input.

  Since the photoelectric separation type smoke detector of the present invention has a light receiving filter that polarizes light, only polarized light in a specific direction can pass through outside light including polarized light in various directions. Can be reduced.

  In addition, since the photoelectric separation type smoke detector of the present invention can change the polarization direction of the light receiving filter, it is possible to change the polarization direction of the reflected light so that it does not coincide with the polarization direction of the reflected light. The influence of light can be reduced.

  The photoelectric separation type smoke detector of the present invention controls the polarization direction of the light receiving filter so that the intensity of external light received by the light receiving unit falls within a predetermined range from the minimum value. Thereby, for example, even if the position where external light is reflected changes and the polarization direction of the reflected light changes, it is possible to perform fire monitoring in a state where the influence of the reflected light is within a predetermined range from the minimum.

  The photoelectric separation type smoke detector of the present invention has a light transmission filter for polarizing light. Thereby, for example, even when the distance between the light receiving unit and the light transmitting unit is changed to a short distance, saturation of the light receiving element can be suppressed without changing the amplification factor of the light receiving unit.

  The photoelectric separation type smoke detector of the present invention performs an operation test and a non-operation test by controlling an angle difference between the polarization direction of the light transmitting filter and the polarization direction of the light receiving filter. Thereby, since the intensity of light passing through the light receiving filter can be easily changed, it is not necessary to separately prepare a test apparatus, and the operation test and the non-operation test can be easily performed.

  Further, in the photoelectric separation type smoke detector of the present invention, since the operation test and the non-operation test are performed by an external operation or a test signal input, even if the photoelectric separation type smoke detector is at a high place. Since it is not necessary to assemble a scaffold or use a heavy stretching device, the test can be easily performed.

It is a schematic block diagram which shows the photoelectric separation-type smoke sensor in Embodiment 1 and 2 of this invention. It is a block diagram which shows the control system of the photoelectric separation-type smoke detector in Embodiment 1 and 2 of this invention. It is a figure which shows the relationship between the light intensity which the light-receiving part of the photoelectric separation type smoke sensor in Embodiment 1 and 2 of this invention receives, and an output voltage. It is a control flowchart of the photoelectric separation-type smoke sensor in Embodiment 1 and 2 of this invention. It is an image figure of the action | operation and non-operation test of the photoelectric separation-type smoke sensor in Embodiment 2 of this invention.

  Hereinafter, the photoelectric separation type smoke detector of the present invention will be described in detail with reference to the drawings.

Embodiment 1 FIG.
FIG. 1 is a schematic configuration diagram showing a photoelectric separation-type smoke detector according to Embodiment 1 of the present invention. (A) is a side view of a schematic configuration of a photoelectric separation type smoke detector. FIG. 4B is a front view of each of the light transmitting unit 20 and the light receiving unit 10.
The photoelectric separation type smoke detector according to the first embodiment includes a light transmitting unit 20 that emits light and a light receiving unit 10 that receives light emitted from the light transmitting unit 20.

As shown in FIG. 1A, the light transmitting unit 20 is arranged in the order of the light transmitting element 23, the lens unit 22, and the light transmitting filter 21 toward the light receiving unit 10.
In addition, as shown in FIG. 1B, the light transmission unit 20 is provided with a lens unit 22 so as to cover the light transmission element 23 in a front view, and the light transmission filter 21 so as to cover the lens unit 22. Is provided.
Under the light transmission filter 21, a substantially disk-shaped light transmission filter driving means 25 is provided in contact with the light transmission filter 21 having a substantially disk shape. The light transmission filter 21 can be rotated by rotating the light transmission filter driving means 25.

  The lens unit 22 provided between the light transmitting element 23 and the light transmitting filter 21 focuses light emitted from the light transmitting element 23. The light transmission filter 21 is a polarizing filter and allows only specific polarized light to pass therethrough. The light transmission filter 21 is rotatably supported, and the polarization direction can be changed by rotating.

As shown in FIG. 1A, the light receiving unit 10 is arranged in the order of a light receiving element 13 (for example, a photodiode), a lens unit 12, and a light receiving filter 11 toward the light transmitting unit 20.
As shown in FIG. 1B, the light receiving unit 10 is provided with a lens unit 12 so as to cover the light receiving element 13 in a front view, and a light receiving filter 11 is provided so as to cover the lens unit 12. ing.
A light receiving filter driving means 15 having a substantially disk shape is provided below the light receiving filter 11 in contact with the light receiving filter 11 having a substantially disk shape, and the light receiving filter 11 is rotated by rotating the light receiving filter driving means 15. Can do.

  The light receiving filter 11 uses a polarizing filter in the same manner as the light transmitting filter 21 and allows only specific polarized light to pass therethrough, thereby reducing the influence of external light. The light receiving filter 11 is rotatably supported, and can change the polarization direction by rotating. The lens unit 12 provided between the light receiving element 13 and the light receiving filter 11 focuses the light that has passed through the light receiving filter 11 onto the light receiving element 13.

The light transmitting filter driving means 25, the light receiving filter driving means 15, the light transmitting filter 21, and the light receiving filter 11 are not limited to the substantially disk shape shown in FIG. 1, and the polarization directions of the light transmitting filter 21 and the light receiving filter 11 are changed. What is necessary is just to be comprised so that it can change.
In the photoelectric separation type smoke detector of the first embodiment configured as described above, the light emitted from the light transmitting unit 20 passes through the light receiving filter 11 and the lens unit 12 of the light receiving unit 10 and enters the light receiving element 13. The smoke is detected by the change of the light intensity.

FIG. 2 is a block diagram showing a control system of the photoelectric separation-type smoke detector according to Embodiment 1 of the present invention.
The light transmitting unit 20 includes a control unit 26 and a power / communication unit 27. The light receiving unit 10 includes a control unit 16, a power / communication unit 17, and a test input unit 18.

  The power source / communication unit 27 of the light transmitting unit 20 and the power source / communication unit 17 of the light receiving unit 10 are connected by an electric wire 30. The electric wire 30 serves both as a signal line and a power line. For example, power is supplied to the power / communication unit 27 from the outside, and power is sent from the power / communication unit 27 to the power / communication unit 17. The electric wire 30 also serves as a synchronization line that performs synchronization between the light transmitting unit 20 and the light receiving unit 10. The power / communication unit 27 and the power / communication unit 17 are connected to a fire receiver (not shown) through a signal line, and communicate with the fire receiver to transmit / receive state information.

  The light transmission unit 20 includes a control unit 26 (for example, a microcomputer), and controls all operations of the light transmission unit 20. The control unit 26 includes a signal output control unit 26a and a light transmission filter control unit 26e. The signal output control unit 26 a controls the power supply / communication unit 27 in order to communicate with the fire receiver or to perform communication for synchronization between the light transmitting unit 20 and the light receiving unit 10.

  In addition, the light transmission filter control unit 26 e sends a command to the light transmission filter driving unit 25 to drive the light transmission filter 21. The light transmission filter driving means 25 is a substantially disk-shaped object, for example, as shown in FIG. 1, and rotates the light transmission filter 21 by being rotated by a motor or the like.

The light receiving unit 10 includes a control unit 16 that controls all operations of the light receiving unit 10. Moreover, the control part 16 has the signal output control part 16a, the test input determination part 16b, the fire determination part 16c, the setting part 16d, and the light reception filter control part 16e.
The signal output control unit 16a controls the power supply / communication unit 17 in order to perform the same operation as the signal output control unit 26a of the light transmission unit 20 described above.

The light receiving filter control unit 16 e drives the light receiving filter 11 by sending a command to the light receiving filter driving means 15. The configurations and functions of the light receiving filter control unit 16e and the light receiving filter driving unit 15 are the same as those of the light transmission filter control unit 26e and the light transmission filter driving unit 25 described above.
When the light receiving element 13 receives the light that has passed through the light receiving filter 11 and the lens unit 12, the light receiving element 13 converts the light into an electrical signal (voltage) corresponding to the light intensity. The electric signal is sent to the amplifier circuit 14 and amplified at an amplification factor controlled by the control unit 16.

  The signal amplified by the amplifier circuit 14 is sent to the control unit 16, and the fire determination unit 16c determines whether there is a fire according to the signal. This determination method determines, for example, a fire by comparing the signal with a predetermined reference value, which will be described in detail later.

  A test input unit 18 is connected to the control unit 16. When performing an operation test or the like, a signal or a contact (switch) input is sent from an external instruction unit (not shown) to the test input unit 18, and the test input unit 18 transmits information such as a test start to the control unit 16. The test input determination unit 16b performs a test determination process when the test input information is obtained from the test input unit 18. The operation test will be described in detail in a second embodiment described later.

  The setting unit 16d is, for example, a ROM, and has information on the distance between the light receiving unit 10 and the light transmitting unit 20 in the monitoring area. For example, a short distance (5 m or more and less than 20 m), a medium distance (20 m or more and less than 40 m), or a long distance (40 m or more and 100 m or less) is set and stored as a code. The setting unit 16d may be a switch such as a dip switch provided outside the control unit 16. The amplification factor of the amplifier circuit 14 described above is adjusted according to the distance set by the setting unit 16d.

For example, when the distance is short, the amplification factor is set low because the light is strong, and when the distance becomes a medium distance, the amplification factor is increased by changing the setting to the medium distance, and the light receiving element 13 outputs. Corresponds to weak voltage.
When the distance between the light receiving unit 10 and the light transmitting unit 20 is changed, the light intensity can be changed using the light transmitting filter 21. For example, if the amplification factor is set high by setting a long distance and the distance becomes short in that state, the angle difference between the polarization directions of the light transmission filter 21 and the light reception filter 11 is increased, The light received by the light receiving element 13 is weakened. Thereby, even if it does not change the setting of the setting part 16d, it can respond to the change of distance, and it can suppress that the light receiving element 13 is saturated and correct light intensity cannot be detected.

FIG. 3 is a diagram showing the relationship between the intensity of light received by the light receiving unit of the photoelectric separation-type smoke detector according to Embodiment 1 of the present invention and the output voltage.
When the external light received by the light receiving unit 10 is small, the light intensity is a low value such as L1 and L2. When the light intensity changes from L2 to L1 due to the generation of smoke, the voltage changes greatly from V2 to V1, and the generation of smoke is detected by this change. Therefore, smoke can be detected with high accuracy.

  On the other hand, when there is a large amount of external light entering the light receiving unit 10, the light intensity is a high value such as L3 and L4. Even when the light receiving element 13 is saturated and the light intensity changes greatly from L4 to L3 due to the generation of smoke, the voltage changes only from V4 to V3. Therefore, it is difficult to determine whether the voltage change is caused by smoke or the influence of noise or the like, and the accuracy of smoke detection is deteriorated.

Since the photoelectric separation type smoke detector of the first embodiment has such characteristics, it is necessary to reduce the light intensity entering the light receiving element 13.
As described above, since the photoelectric separation type smoke detector according to the first embodiment includes the light receiving filter 11, it does not pass light other than a specific polarization direction. Therefore, the influence of external light entering the light receiving element 13 can be reduced, and the light intensity can be reduced.

In addition, for external light, light having various polarization directions is mixed, but for reflected light, the polarization directions are relatively uniform. In addition, as the position of the sun moves with time, the polarization of reflected light also changes with time. Therefore, the light receiving filter 11 is rotated in accordance with the change in the polarization, and the angle of the polarization direction of the light receiving filter 11 is set to an angle different from the polarization of the reflected light. For example, by changing the angle of the polarization direction of the light receiving filter 11 to an angle orthogonal to the polarization direction of the reflected light entering the light receiving filter 11, the influence of the reflected light can be within a predetermined range from the minimum. it can. Therefore, the influence of the reflected light entering the light receiving element 13 can be reduced, and the light intensity can be reduced.
The light transmission filter control unit 26e, the light transmission filter driving means 25, and the light transmission filter 21 are mainly used in the second embodiment to be described later, and thus are not necessarily provided in the first embodiment. It is not necessary.

Next, the operation of the photoelectric separation type smoke sensor configured as described above will be described.
FIG. 4 is a control flowchart of the photoelectric separation-type smoke detector according to Embodiment 1 of the present invention.
The photoelectric separation type smoke detector according to the first embodiment emits light every predetermined time to detect smoke. When light is emitted, in step 1, a synchronization pulse is transmitted from the control unit 16 of the light receiving unit 10 to the control unit 26 of the light transmission unit 20 via the electric wire 30. In step 2, the light receiving filter control unit 16e and the light transmission filter control unit 26e rotate the light receiving filter 11 and the light transmission filter 21 by driving the light receiving filter driving unit 15 and the light transmission filter driving unit 25. Here, the light receiving filter 11 and the light transmitting filter 21 rotate with their polarization directions being matched so that the light receiving voltage falls within a predetermined range from the minimum value. As described above, since the polarization directions of the light receiving filter 11 and the light transmitting filter 21 are matched, the light for smoke detection from the light transmitting unit 20 is not attenuated by the light receiving filter 11. When the light transmission filter 21 is not provided, the light reception filter 11 is rotated so that the light reception voltage is within a predetermined range from the minimum value. Thereby, as described above, the influence of the reflected light of the external light is reduced.

  In step 3, the control unit 16 measures the received light voltage. In step 4, the control unit 16 calculates the light attenuation rate using the light reception voltage measured in step 3 and the reference value calculated in advance. Here, the reference value is an average value of the received light voltage within a predetermined time immediately before (for example, 1 hour). The dimming rate is calculated as dimming rate = (reference value−light receiving voltage) / reference value. Then, the processes in steps 3 and 4 are performed a plurality of times, and in step 5, the control unit 16 performs an averaging process on the plurality of calculated attenuation rate data. In this averaging process, for example, an average value of the light extinction rate data of the latest six times is calculated.

  In step 6, the fire determination unit 16 c performs the fire determination process by comparing the averaged light attenuation rate data with a predetermined fire threshold value. In step 7, when the fire determination unit 16c determines that a fire has been detected based on the determination result, the process proceeds to step 8 where a fire signal is issued and a fire receiver (not shown) or the like is displayed as a fire. To do.

  If no fire is detected in step 7, the control unit 16 determines in step 9 whether it is the update time of the reference value. The reference value is the value used in step 4, and as described above, the environment of the monitoring space such as the intensity of external light entering the light receiving unit 10 and the amount of dust changes with time. Update every hour. If it is not the update time of the reference value, the process proceeds to step 13, and if it is the update time of the reference value, the process proceeds to step 10 and the control unit 16 calculates a new reference value. As this new reference value, for example, the average value of the received light voltage for the previous hour is used.

In step 11, the control unit 16 determines whether the new reference value is normal. If smoke or dust is generated in the monitored area and is dimmed to some extent, the received light voltage at that time is lower than normal. If the new standard value is calculated in such an environment, even if a fire occurs and smoke is generated, the dimming rate is less likely to decrease as the fire threshold is reached, compared to the new standard value. In step 6, it cannot be determined as a fire. For this reason, in step 11, the control unit 16 determines that the new reference value compared with the old reference value is normal if the change is within a predetermined range.
If the new reference value is normal, the reference value is updated using the new reference value. If the new reference value is not normal, the process proceeds to step 13 without updating. In step 13, the process waits until the next light emission time, and proceeds to step 1 when the light emission time is reached. This waiting time is, for example, 1 minute.

As shown in step 2 above, the photoelectric separation type smoke detector of the first embodiment rotates the light receiving filter 11 and the light transmitting filter 21 while keeping the polarization directions coincident, thereby reducing the light receiving voltage from the minimum value. Set within a predetermined range. Thereby, the influence of external light can be suppressed.
Further, as shown in Step 9 to Step 12, since the reference value is changed every predetermined time and the light attenuation rate is calculated, the amount of external light and reflected light entering the light receiving unit 10 changes with time. However, the influence can be suppressed.

As described above, since the photoelectric separation type smoke detector according to the first embodiment includes the light receiving filter 11, it does not pass light other than a specific polarization direction, so that the influence of external light can be reduced. it can. Therefore, since the light intensity received by the light receiving unit 10 can be easily reduced, smoke can be detected with high accuracy.
Further, the light receiving filter 11 is driven so that the intensity of light passing through the light receiving filter 11 falls within a predetermined range from the minimum value. Thus, for example, even if the position where external light is reflected changes and the polarization direction of the reflected light changes, fire monitoring can be performed in a state where the influence of the reflected light of the external light is within a predetermined range from the minimum. it can.
Moreover, since the light transmission filter 21 is provided, even if the distance between the light receiving unit 10 and the light transmission unit 20 is short, the light can be attenuated correspondingly, so that the light receiving element 13 may be saturated. Can be suppressed.

Embodiment 2. FIG.
In the second embodiment, an example in which operation and non-operation tests are performed using the photoelectric separation type smoke sensor shown in the first embodiment will be described.
FIG. 5 is an image diagram of the operation and non-operation test of the photoelectric separation type smoke detector according to the second embodiment of the present invention.
This test is performed by matching the polarization directions of the light transmitting filter 21 and the light receiving filter 11 by the process shown in Step 2 of FIG. 4, and the light receiving voltage is in a predetermined range from the minimum value, that is, the influence of external light. It is performed in a state within a predetermined range from the minimum.

First, a test is started by sending a command to trigger a test start from an external instruction unit (not shown) to the test input unit 18. The instructing unit is provided with a switch or the like, for example, and a test start command is sent by operating the switch. The instruction unit may be, for example, an existing fire receiver that sends a test signal from the fire receiver. Further, the transmission from the instruction unit to the test input unit 18 may be an electrical signal, or may be wireless or wired communication. Moreover, it may be based on light such as infrared rays.
For example, it is assumed that an operation test (a test for confirming that a fire is not detected) is performed with a first trigger, and an operation test (a test for confirming that a fire is detected) is performed with a second trigger.

  In the inoperative test, the light transmission filter 21 is shifted by 30 °, and the difference in polarization direction between the light transmission filter 21 and the light reception filter 11 is set to 30 °. Since the influence of external light changes when the light receiving filter 11 is shifted, the light transmitting filter 21 is shifted. As a result, the light from the light transmitting element 23 is attenuated and enters the light receiving element 13, but not so attenuated that it is determined as a fire. Check that no fire is detected within 30 seconds in this state. This determination is the same as the fire determination shown in step 6 of FIG.

  Next, in the operation test, the light transmitting filter is shifted to 45 °, and the difference in the polarization direction between the light transmitting filter 21 and the light receiving filter 11 is set to 45 °. As a result, the light from the light transmitting element 23 is further attenuated and enters the light receiving element 13, so that the amount of smoke is increased to the same attenuation as when the fire has progressed. In this state, confirm that a fire is detected within 30 seconds.

The photoelectric separation type smoke detector according to the second exemplary embodiment of the present invention confirms that the device is operating normally by performing the above test.
The rotation angle and test time of the above-mentioned light transmission filter 21 are examples, and differ depending on the performance and installation environment of the photoelectric separation type smoke detector.
Further, the rotation angle and the test time may be those previously stored in the control unit 26 or the like, or may be set with a dial or the like for each test.

  In addition, the photoelectric separation type smoke sensor according to the second embodiment of the present invention is often mounted at a high place. Therefore, it is desirable to provide an instruction unit (not shown) for sending a command to the test input unit 18 in a place remote from the photoelectric separation type smoke detector and easily operated by the user.

As described above, the photoelectric separation type smoke detector according to the second exemplary embodiment of the present invention can change the received light intensity by changing the angle difference between the polarization direction of the light transmission filter 21 and the polarization direction of the light reception filter 11. it can. Therefore, it is not necessary to separately prepare a test device such as a lattice filter, and the operation test and the non-operation test can be easily performed.
In addition, since the operation and non-operation tests can be performed by an external operation or a test signal, it is not necessary to assemble a scaffold or use a heavy stretching device, so that the test can be easily performed.

  DESCRIPTION OF SYMBOLS 10 Light receiving part, 11 Light receiving filter, 12 Lens part, 13 Light receiving element, 14 Amplifier circuit, 15 Light receiving filter drive means, 16 Control part, 16a Signal output control part, 16b Test input determination part, 16c Fire determination part, 16d Setting part , 16e Light receiving filter control unit, 17 Power supply / communication unit, 18 Test input unit, 20 Light transmission unit, 21 Light transmission filter, 22 Lens unit, 23 Light transmission element, 25 Light transmission filter driving means, 26 Control unit, 26a Signal Output control part, 26e Light transmission filter control part, 27 Power supply and communication part, 30 Electric wire.

Claims (6)

A light transmitter that emits light;
A light receiving unit that receives light emitted from the light transmitting unit;
In the photoelectric separation type smoke detector equipped with
The photoelectric separation type smoke detector, wherein the light receiving unit includes a light receiving filter that polarizes light received by the light receiving unit.   The photoelectric separation type smoke detector according to claim 1, wherein a polarization direction of the light receiving filter is changeable.   The photoelectric separation type according to claim 2, further comprising a control unit that controls a polarization direction of the light receiving filter so that an intensity of external light received by the light receiving unit falls within a predetermined range from a minimum value. smoke detector. The light transmitting unit includes a light transmitting element that emits light, and a light transmission filter that polarizes light emitted from the light transmitting element,
The operation test and the non-operation test are performed by changing a polarization direction of the light transmission filter to control an angle difference between the polarization direction of the light transmission filter and the polarization direction of the light reception filter. The photoelectric separation type smoke detector according to any one of claims 1 to 3.   The photoelectric separation type smoke sensor according to claim 4, wherein the operation test and the non-operation test are performed by an external operation or a test signal input.   The photoelectric separation type smoke detector according to claim 1, wherein the light transmission unit includes a light transmission filter that polarizes light.

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