JP6416526B2 - Flame detector - Google Patents

Description

The present invention relates to a flame detector for detecting a fire, and more particularly to a flame detector having a function of measuring the degree of contamination of a light receiving window.

  The flame detector is provided with a light receiving window, and infrared rays emitted from the flame are received by the light receiving element after passing through the light receiving window. For this reason, if the light receiving window is contaminated with dust or the like, the infrared rays are hardly transmitted, and it is difficult to perform highly accurate flame detection.

  Therefore, in order to measure the degree of contamination of the light receiving window provided in the approximate center of the main body cover, the test light source for irradiating the test light provided in the main body cover and the back surface of the light receiving window are disposed in the vicinity of the above problem. There has been developed a fire detector with a contamination degree measurement test function that includes a light receiving element that receives light from a test light source (see, for example, Patent Document 1).

JP 2005-122437 A

FIG. 7 shows a conventional flame detector described in Patent Document 1. About the same structure as the flame detector of Example 1, the code | symbol is abbreviate | omitted about one part. FIG. 2 is a view of the flame detector as viewed from below when the ceiling is installed, and FIG. 7 is a schematic vertical sectional view taken along the line I-I. 1000 is a flame detector, 7 is a light receiving window, 8 is a light receiving element, 3 is a body cover, 22 is a light receiving element for measuring the degree of contamination, and 100 is a light emitting element for measuring the degree of contamination.
The contamination degree measuring light emitting element 100 is a light emitting diode that emits test light in the near-infrared wavelength band, and its lead wire portion 100b is attached to the circuit board 5 via a socket 100c. The lamp portion 100a of the contamination degree measuring light emitting element 100 is located in the second storage chamber 21 in the vicinity of the bottom side of the lowermost surface of the main body cover 3, and the lead wire portion 100b is bent, so that the lamp The portion 100a is bent at a predetermined bending angle, for example, 18 degrees and directed toward the light receiving window 7, and is directed in a direction in which the optical axis of the contamination degree measuring light receiving element 22 described later faces each other.

The contamination degree measuring light receiving element 22 for receiving the test light from the contamination degree measuring light emitting element 100 is mounted directly attached to the circuit board 5 at a position avoiding the inside of the opening 6.
Here, the position avoiding the opening refers to a position that is not relative to the opening and refers to a region in which external light is difficult to enter from the opening, for example, outside the light receiving element housing portion 13. The contamination degree measuring light receiving element 22 is a Si photodiode having sensitivity in a wavelength band from visible light to near infrared light, and its light receiving surface is formed of a visible light cut member. The contamination degree measuring light receiving element 22 is located on the opposite side of the contamination degree measuring light emitting element 100 via the light receiving element accommodating portion 13 in the circuit board 5, and the lead wire portion 22b is further bent, and the light receiving portion 22a. Is directed to the direction in which the optical axis of the contamination degree measuring light emitting element 100 and the mutual optical axis face each other.
Since the test light is attenuated by the degree of contamination of the light receiving window 7, the degree of contamination can be measured from the output of the contamination degree measuring light receiving element 22.

However, in the conventional flame detector 1000 described above, since the position of the lamp portion 100a in the contamination degree measuring light emitting element 100 is far from the circuit board 5, it is necessary to adjust the light emitting direction during manufacturing. Further, even if the adjustment is made, the light emission direction is not stable, and there is a possibility that the amount of light received by the contamination measuring light-receiving element 22 varies.
SUMMARY OF THE INVENTION In view of the above circumstances, an object of the present invention is to prevent variations in the light emission direction of a contamination degree measuring light emitting element and the amount of light received by the contamination degree measuring light receiving element in a flame detector.

The present invention solves the above problems and is as follows.
A case made of a main body and a main body cover connected to the main body and having an opening, a circuit board housed in the case, and a light receiving window made of a material that transmits infrared rays, is incident from the opening. A light receiving element that receives infrared rays emitted from a flame, a light emitting element for measuring the degree of contamination for emitting a test light for performing a degree of contamination measurement test of the light receiving window, and the test light received through the light receiving window. A flame detector comprising: a light receiving element for measuring the degree of contamination, wherein a fixing spacer for attaching the light emitting element for measuring the degree of contamination to the circuit board is provided, and the light emission for measuring the degree of contamination is provided on the fixed spacer. A flame detector characterized in that the light emitting direction of the pollution degree measuring light emitting element is fixed in a predetermined direction by positioning and fixing the lamp portion of the element.

The invention of the present application has the following effects.
(1) It is not necessary to adjust the light emission direction of the light emitting element for measuring the degree of contamination at the time of production, and the number of production steps is reduced and productivity is improved.
(2) Since the light emitting direction of the pollution degree measuring light emitting element is stabilized, the yield can be increased.
(3) The light emitting element can be fixed at an accurate position during production, and is less susceptible to external factors such as vibration at the site, so that abnormal malfunctions at the site can be reduced.

The flame detector in Example 1. FIG. 3 is a schematic longitudinal sectional view taken along line II in FIG. 2. The figure which looked at the flame detector of the prior art and Example 1 from the bottom at the time of ceiling installation. 1 is a perspective view of a pollution degree measuring light-emitting element 10 in Example 1. FIG. The fixed spacer 50 in Example 1. FIG. In Example 1, the figure which shows the state which attached the fixed spacer 50 grade | etc., To the circuit board 5. FIG. The light emission characteristic of the light emitting element 10 for measuring the contamination degree Conventional flame detector. FIG. 3 is a schematic longitudinal sectional view taken along line II in FIG. 2.

  Embodiments of the present invention will be described below. The same parts as those of the conventional example shown in FIG.

FIG. 1 is a diagram of a flame detector 1 showing Embodiment 1 of the present invention, and is a schematic longitudinal sectional view taken along line II of FIG.
The flame detector 1 includes a case 4 including a main body 2 and a main body cover 3 connected to the main body 2, and is attached to a ceiling surface or the like by being connected to an attachment base by a blade fitting (not shown). FIG. 2 is a view as seen from below with the flame detector 1 attached to the ceiling.

  The body cover 3 is formed in a frustoconical shape, and an opening 6 formed by a bottom wall 6b having an opening and a side wall 6a is formed in a concave portion at the center of the bottom surface. Further, the body cover 3 is formed with a cap fitting portion 11, which is fitted with the cap fitting portion 11 and made of a methacrylic resin material that accommodates the operation check lamp 9 and the lightness measuring element 10 for measuring the degree of contamination. A transparent translucent cap 11a is provided.

  The light receiving element 8 is housed in the light receiving element housing portion 13, and is mounted on the circuit board 5 so that the light receiving portion 8 a is positioned relative to the opening 6 of the main body cover 3. The light receiving element accommodating portion 13 surrounds the light receiving element 8 and has a cylindrical light receiving element holder 15 that fixes the band pass filter 14 at a relative position with respect to the light receiving portion 8a of the light receiving element 8, and the light receiving element holder 15 A transparent cylindrical light receiving element made of a methacrylic resin material, in which a light receiving window 7 disposed in front of the light receiving element 7 and a light receiving element holder 15 are housed and which fixes the light receiving window 7 at a relative position with respect to the light receiving portion 8a of the light receiving element 8. And a cover 16. The light receiving element cover 16 includes a third light transmission window 16a that transmits the test light emitted from the contamination degree measuring light emitting element 10 toward the contamination degree measuring light receiving element 22 described later.

Since the light receiving element cover 16 is in contact with the inner surface of the bottom wall 6b of the concave opening 6, the opening of the opening 6 is connected to the light receiving element housing 13. . In the light receiving element accommodating portion 13, an engagement 17 is formed by a plurality of locking holes 16b and protrusions 15c (only one set shown in FIG. 1) corresponding to the light receiving element cover 16 and the light receiving element holder 15. The holder 15 is attached to the circuit board 5 by being engaged with the circuit board 5 (not shown). The band-pass filter 14 has a property of transmitting only light rays within a specific wavelength band, and in the present embodiment, only infrared rays in the wavelength band of CO ₂ resonance radiation emitted from the flame are used. It is used to transmit. The light receiving window 7 is made of a material that transmits infrared rays, for example, sapphire glass.

  Thereby, in the flame detector 1, infrared rays emitted from the flame are incident from the opening 6 of the main body cover 3, pass through the light receiving window 7 and the band pass filter 14, and are received by the light receiving portion 8 a of the light receiving element 8. Accordingly, the light receiving element 8 can detect the occurrence of the flame by detecting the infrared ray.

  The translucent cap 11 a accommodates the operation check lamp 9, the first storage chamber 19 having the first light transmission window 18 for the operation check lamp 9, and the pollution measuring light emitting element 10. And a second storage chamber 21 having a second light transmission window 20 for the measurement light emitting element 10. The first storage chamber 19 has a substantially box shape having no surface on the circuit board 5 side, and the second storage chamber 21 has a substantially box shape having no surface on the circuit board 5 side and the surface side of the main body cover 3. Is. A surface of the second housing chamber 21 on the surface side of the main body cover 3 is closed by the main body cover 3.

  In the translucent cap 11a, the first translucent window 18 is formed in a quadrangular pyramid shape and the surface is formed in a satin shape, and is provided to project outward from the surface of the main body cover 3. The translucent window 20 is formed on the side wall 21 a of the second storage chamber 21 and is provided facing the opening 6 of the main body cover 3.

  The circuit board 5 accommodated in the case 4 is connected with an operation check lamp 9, a contamination degree measuring light emitting element 10, and a contamination degree measuring light receiving element 22 together with a light receiving element 8 for detecting flame. In the first embodiment of the present invention, the operation check lamp 9 and the pollution degree measuring light emitting element 10 are fixed to the circuit board 5 while being mounted on the fixed spacer 50. The fixing spacer 50 extends downward from the circuit board 5 and positions and fixes the lamp portion 10a of the pollution degree measuring light emitting element 10, whereby the light emitting direction of the lamp portion 10a is fixed in a predetermined direction.

  FIG. 3 is a perspective view of the contamination degree measuring light emitting element 10, which includes a lamp portion 10 a and a lead wire portion 10 b.

  FIG. 4 shows the fixed spacer 50. When the flame detector 1 is installed on the ceiling, it is upside down. 4 (a) is a side view, and FIG. 4 (b) is a view seen obliquely from above (or obliquely below in the ceiling installation state). 4 will be described based on the vertical relationship of FIG. 4, not the ceiling installation state of the flame detector 1. As shown in FIG. 4A, the fixed spacer 50 has a structure in which a high platform portion 50a and a low platform portion 50b are connected, and has three fixed legs 50c in the lower portion. The fixed spacer 50 is fixed to the circuit board 5 by the fixed legs 50c.

The hill part 50a has a lamp part mounting part 50d at the upper part thereof, a lamp back fixing part 50e on the lower part part 50b side, and a lamp front side fixing part 50f on opposite sides. As shown in FIG. 4 (b), the front lamp side fixing portion 50f is divided into two, and there is a front lamp groove 50g therebetween. With these structures, the lamp portion 10a of the pollution degree measuring light emitting element 10 is fixed.
The hill portion 50a is provided with lead wire receiving grooves 50h on both side surfaces thereof, and a lead wire insertion hole 50i is provided at the lower portion. Through these, the lead wire portion 10b of the pollution degree measuring light emitting element 10 is directly attached to the circuit board 5.
There is a confirmation lamp mounting part 50j on the upper part of the low platform part 50b, and a confirmation lamp lead wire insertion part 50k is provided from the surface to the lower part. Then, the operation check lamp 9 is mounted, and the lead wire portion 9b is directly attached to the circuit board 5 via the check lamp lead wire insertion portion 50k.

  FIG. 5 is a diagram illustrating a state in which the contamination degree measuring light emitting element 10 and the like are attached to the circuit board 5. The light-emitting element 10 for measuring the degree of contamination is attached to the circuit board 5 after being attached to the fixed spacer 50 together with the operation check lamp 9. The contamination measuring light emitting element 10 is installed so as to straddle the lamp mounting part 50d of the fixed spacer 50. The lamp part 10a is fixed by the lamp back fixing part 50e and the lamp front side fixing part 50f, and the lead wire part 10b. Is housed in the lead wire housing groove 50h and connected to the circuit board 5 through the lead wire insertion hole 50i. The operation check lamp 9 is mounted on the check lamp mounting portion 50j, and is connected to the circuit board 5 through the check lamp lead wire insertion portion 50k. Further, the light receiving element 22 for measuring the degree of contamination is also attached to the circuit board 5. The lamp unit 10 a is located away from the circuit board 5 and emits near-infrared test light toward the contamination measuring light-receiving element 22 attached in the vicinity of the circuit board 5. As indicated by the arrows in FIG. 5, near-infrared light enters from the light receiving window 7, passes through the third light transmitting window 16 a, and is received by the contamination degree measuring light receiving element 22. Since the lamp portion 10a is fixed to the tip of the fixed spacer 50, the position and direction do not shift.

  The pollution degree measuring light emitting element 10 and the operation check lamp 9 are inserted into the translucent cap 11 a while being mounted on the fixed spacer 50. The contamination degree measuring light emitting element 10 is located in the second storage chamber 21, and light from the lamp portion 10 a is emitted toward the contamination degree measuring light receiving element 22 through the second light transmission window 20. Further, the light emitting portion 9a of the operation check lamp 9 is located in the first storage chamber 19 of the translucent cap 11a.

  FIG. 6 shows the light emission characteristics of the contamination degree measuring light emitting device 10 in Example 1. In this element, the amount of light emitted in the vicinity of 10 degrees is the highest, but in this embodiment, light emitted in the direction of -20 to -30 degrees is used. That is, it is installed so that the direction of the contamination degree measuring light receiving element 22 is -20 to -30 degrees. In this direction, it is not only necessary to change the direction of the lamp unit 10a, but even if the angle is changed a little, the amount of emitted light is hardly changed, so that the emitted light intensity has angular stability. In this respect as well, variations in the contamination degree measuring light receiving element 22 hardly occur.

The contamination degree measuring light receiving element 22 that receives light from the contamination degree measuring light emitting element 10 is mounted directly attached to the circuit board 5 at a position avoiding the inside of the opening 6.
Here, the position avoiding the opening refers to a position that is not relative to the opening and refers to a region in which external light is difficult to enter from the opening, for example, outside the light receiving element housing portion 13. The contamination degree measuring light receiving element 22 is a Si photodiode having sensitivity in a wavelength band from visible light to near infrared light, and its light receiving surface is formed of a visible light cut member. The contamination degree measuring light receiving element 22 is located on the opposite side of the contamination degree measuring light emitting element 10 through the light receiving element accommodating portion 13 in the circuit board 5, and the lead wire portion 22b is further bent, and the light receiving portion 22a. However, it is bent at a predetermined bending angle so that the pollution degree measuring light emitting element 10 and the optical axis of each other face each other.

Next, the operation of the flame detector according to the first embodiment will be described.
During fire monitoring:
In FIG. 1, the light receiving element 8 monitors the flame through the light receiving window 7. When a fire occurs, the infrared rays generated by the fire pass through the opening 6, the light receiving window 7, and the band pass filter 14 and are received by the light receiving element 8, so that the fire can be detected.

During a light-receiving window contamination degree measurement test:
When power is supplied to the light emitting element 10 for measuring the degree of contamination, near-infrared test light is generated. The lamp portion 10a is fixed in position by a fixing spacer 50, and the test light is, as shown in FIGS. 1 and 5, the second light transmitting window 20, the light receiving window 7, and the light receiving element holder 15 of the light transmitting cap 11a. Are transmitted through the notch 15a and the third light transmission window 16a of the light receiving element cover 16 and are accurately received by the contamination measuring light receiving element 22.
Since the test light is attenuated by the degree of contamination of the light receiving window 7, the degree of contamination is measured from the output of the contamination degree measuring light receiving element 22.
Correction of the signal obtained from the light receiving element 8 and abnormality notification of the flame detector 1 are performed based on the measured degree of contamination.

  The light receiving element accommodating portion 13 has a windproof function and can prevent the light receiving element 8 from being influenced by outside air.

A plurality of other embodiments of the present invention will be described by showing differences from the first embodiment.
(1) The contamination measuring light-receiving element 22 is mounted on the fixed spacer 50 with the positions of the contamination measuring light-emitting element 10 and the contamination measuring light-receiving element 22 reversed. As a result, the light receiving direction is fixed, so that the light receiving sensitivity is stabilized. Further, both the contamination degree measuring light emitting element 10 and the contamination degree measuring light receiving element 22 may be fixed by fixing parts or the like.

(2) The fixed spacer 50 has a shape protruding from the circuit board 5 in an oblique direction. Then, even if it does not use the light emission in the oblique direction of the light emitting element 10 for contamination degree measurement as in the first embodiment, light emission in an arbitrary direction can be used if the inclination of the fixed spacer 50 is changed, and various light emission characteristics are different. The light emitting element can be used. Further, the fixed spacer 50 may be inclined only in the vicinity of the lamp portion mounting portion 50d with which the lamp portion 10a abuts so that the direction is directed to the contamination degree measuring light receiving element 22, and the lead wire of the contamination degree measuring light emitting element 10 An arbitrary angle may be provided in the lamp mounting portion 50d of the fixed spacer 50 for passing the portion 10b, the lead wire receiving groove 50h, the lead wire insertion hole 50i, and the like. In these cases, the translucent cap 11a and the like are designed so that the second accommodation chamber 21 has a shape and size that can accommodate the fixed spacer 50 and the like.

(3) In the first embodiment, the fixing spacer 50 is fixed to the circuit board 5 and defines the direction of the lamp unit 10 a, but may be fixed to the main body cover 3. In this case, after fixing the fixing spacer 50 mounting the light emitting element 10 for measuring the degree of contamination to the main body cover 3, the lead wire portion 10b and the like are connected to the circuit board 5 by soldering or a connector.
In addition, the lamp unit 10a may be installed in the conventional manner without being fixed to the fixed spacer 50 by using only the light emission characteristic having the angle stability in the direction of -20 to -30 degrees in FIG. .

DESCRIPTION OF SYMBOLS 1 Flame detector, 2 main body, 3 main body cover, 4 case, 5 circuit board, 6 opening part, 7 light receiving window, 8 light receiving element, 9 operation check lamp, 10 light emitting element for contamination degree measurement, 10a light part, 10b lead Line part, 11 Cap fitting part, 11a Light transmission cap, 13 Light receiving element accommodating part, 14 Band pass filter, 15 Light receiving element holder, 16 Light receiving element cover, 16a 3rd light transmission window, 18 1st light transmission window , 19 1st accommodating chamber, 20 2nd light transmission window, 21 2nd accommodating chamber, 21a side wall, 22 Light receiving element for contamination degree measurement, 50 fixed spacer, 50a high base part, 50b low base part, 50c fixed leg 50d Lamp part mounting part, 50e Lamp back fixing part, 50f Lamp front side fixing part, 50g Lamp front groove, 50h Lead wire storage groove, 50i Lead wire insertion hole, 50j Confirmation lamp mounting part, 50k confirmation Lead wire insertion section, 100 defacement degree-measuring light-emitting devices, 100a lamp unit, 100b lead portion 100c spacer 1000 flame detector

Claims (2)

A case comprising a main body and a main body cover coupled to the main body and having an opening;
A circuit board housed in the case;
A light receiving element that receives infrared rays emitted from a flame incident from the opening through a light receiving window made of a material that transmits infrared rays;
A light emitting element for measuring the degree of contamination having a lead wire part and a lamp part for emitting test light for performing a degree of contamination measurement test of the light receiving window;
A flame detector comprising: a contamination degree measuring light receiving element that receives the test light through the light receiving window,
A fixing spacer for attaching the light emitting element for measuring the degree of contamination to the circuit board is provided,
The light emitting direction of the contamination degree measuring light emitting element is fixed in a predetermined direction by positioning and fixing the lamp portion so that the contamination degree measuring light emitting element straddles the lamp portion mounting portion of the fixed spacer. A flame detector characterized by   The fixed spacer has a high base part and a low base part,
  The hill part includes a lead wire storage groove on both sides, a lamp back fixing part and a lamp front side fixing part on the top part, and a lead wire insertion hole on the bottom part,
  The low base part has a confirmation lamp mounting part on which an operation confirmation lamp is mounted, and a confirmation lamp lead wire insertion part,
  The lead wire portion of the contamination degree measuring light emitting element is housed in the lead wire housing groove and inserted into the lead wire insertion hole,
  The flame detector according to claim 1, wherein the lamp part is fixed by the lamp back fixing part and the lamp front side fixing part.

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