JP2019188378A - Filter manufacturing method and smoke detector - Google Patents

Abstract

To provide a filter manufacturing method that can improve filter performance and a smoke detector.SOLUTION: A filter manufacturing method comprises a first step, a second step and a third step. In the first step, a first molded body 11 including filter parts 723 and a connection part 725 is subjected to injection molding. The filter parts 723 have a plurality of opening parts 7231 and a plurality of linear parts 7232 positioned between two adjacent opening parts 7231 respectively of the plurality of opening parts 7231. The connection part 725 is joined to the filter parts 723. In the second step, the first molded body 11 is folded back at a boundary between the filter parts 723 and the connection part 725 to form a cubic-shape body 13. In the third step, a second molded body 12 is molded integrally with the cubic-shape body 13 by resin molding to form a cylindrical body 14 including the filter parts 723 as a part of a side wall 141.SELECTED DRAWING: Figure 1

Description

  The present disclosure relates generally to a method for manufacturing a filter and a smoke sensor, and more particularly to a method for manufacturing a filter that has a plurality of openings through which gas passes and filters foreign substances in the gas, and a smoke sensor including the filter.

  Conventionally, a smoke detection type alarm (smoke detector) employing a smoke detector is known (Patent Document 1). The smoke detector described in Patent Literature 1 includes an optical base, a light emitting diode, a photodiode, and an insect net (filter). The insect screen is porous and prevents insects and dust from entering the optical chamber.

JP 2009-199518 A

  In the insect net described in Patent Document 1, in order to make the mold structure for molding a simple structure, the penetration directions of all holes (openings) are parallel to each other. For this reason, the inflow direction of smoke (gas) to the insect screen (filter) is restricted, and the filter performance may be deteriorated.

  An object of the present disclosure is to provide a filter manufacturing method and a smoke detector capable of improving filter performance.

  The manufacturing method of the filter concerning one mode of this indication is provided with the 1st process, the 2nd process, and the 3rd process. In the first step, a first molded body including a filter part and a connecting part is injection molded. The filter section includes a plurality of openings and a plurality of linear portions each positioned between two adjacent openings of the plurality of openings. The said filter part is connected to the said connection part. In the second step, the three-dimensionally shaped body is formed by bending the first molded body at the boundary between the filter portion and the connecting portion. In the third step, a cylindrical body including the filter portion as a part of the side wall is formed by integrally molding the second molded body into the solid body by resin molding.

  A smoke detector according to an aspect of the present disclosure includes a filter that prevents foreign matter from entering the smoke sensing space from an external space. The filter includes a three-dimensionally shaped body and a second molded body. In the three-dimensionally shaped body, in the first molded body including a plurality of filter parts arranged in a circumferential direction and a disk-like connection part connected to the plurality of filter parts, the plurality of filter parts are the connection parts. It is bent at the boundary. Each of the plurality of filter portions has a plurality of openings. The second molded body is integrally formed with the three-dimensional shape body. The filter includes a cylindrical body that includes the three-dimensionally shaped body and the second molded body and includes the plurality of filter portions as a part of a side wall.

  The filter manufacturing method and the smoke detector according to the present disclosure can improve the filter performance.

1A to 1C are explanatory views of a method for manufacturing a filter according to an embodiment. FIG. 2A is a plan view of a first molded body formed in the above-described filter manufacturing method. FIG. 2B is a cross-sectional view taken along line XX of FIG. 2A regarding the first molded body formed in the manufacturing method of the filter. FIG. 3 is an explanatory diagram of a first step in the above-described filter manufacturing method. FIG. 4 is an explanatory diagram of the inflow direction of gas (smoke) to the filter manufactured by the above-described filter manufacturing method. FIG. 5A is an external perspective view of the smoke detector according to the embodiment as viewed obliquely from below. FIG. 5B is an external perspective view of the above smoke detector as viewed obliquely from above. FIG. 6 is an exploded perspective view of the above smoke detector as viewed obliquely from below. FIG. 7 is an exploded perspective view of the above smoke detector as viewed obliquely from above. FIG. 8 is a partially broken perspective view of the smoke sensor. FIG. 9A is an exploded perspective view of a sensing block in the smoke detector. FIG. 9B is an enlarged view of the filter portion of the sensing block in the smoke detector. FIG. 10 is a plan view of the detection block of the smoke detector same as above with the filter removed. FIG. 11 is an explanatory diagram of the filter manufacturing method according to the first modification of the embodiment. 12A to 12C are explanatory diagrams of a method for manufacturing a filter according to Modification 2 of the embodiment. FIG. 13A is a plan view of a first molded body formed in the method for manufacturing a filter according to Modification 3 of the embodiment. FIG. 13B is a side view of a first molded body formed in the above-described filter manufacturing method. FIG. 14 is an explanatory diagram of the filter manufacturing method of the above.

(Embodiment)
(1) Outline The smoke detector according to the present embodiment is a disaster prevention device that issues a notification when smoke generated by a fire or the like is detected. That is, when smoke is generated in the event of a disaster such as a fire, the smoke detector detects the smoke and, for example, issues a warning by outputting an alarm sound or interlocking with other devices by a communication function. The “disaster prevention device” as used in the present disclosure is a device that is installed in a facility for the purpose of, for example, preventing disasters such as fire, preventing the spread of damage caused by disasters, or recovering from disasters.

  As shown in FIGS. 5A to 8, the smoke detector 1 includes a housing 2 and accommodates various components in the housing 2. The smoke detector 1 is installed and used in a facility. In the present embodiment, the case where the smoke detector 1 is used in a non-residential facility such as a hotel, office building, school, welfare facility, commercial facility, theme park, hospital or factory is exemplified. Not limited to this, the smoke detector 1 may be used in a facility such as an apartment house or a detached house. The smoke detector 1 is installed in a facility in a state of being attached to a ceiling, a wall, or the like, for example, in a room, hallway or stairs of the facility.

  As shown in FIGS. 6 and 7, the smoke detector 1 according to the present embodiment includes a housing 2, a photoelectric smoke detection block 10, and a sound output unit 61. The housing 2 has a first cover 21 and a second cover 22. The housing 2 is attached to the construction surface with the second cover 22 facing the construction surface. The smoke detection block 10 has a smoke detection space Sp1 (see FIG. 8) in which smoke from the outside can enter and exit. The smoke detection block 10 detects smoke in the smoke detection space Sp1. Here, the smoke detection block 10 includes a light emitting element 4 and a light receiving element 5. The light emitting element 4 emits light to the smoke sensing space Sp1. The light receiving element 5 is at a position where direct light from the light emitting element 4 does not enter, and light (scattered light) emitted from the light emitting element 4 and scattered by smoke (smoke particles) in the smoke sensing space Sp1 enters. Be placed. Thereby, in the state where smoke does not exist in the smoke sensing space Sp1, the light receiving element 5 does not receive the light emitted from the light emitting element 4, and in the state where smoke exists in the smoke sensing space Sp1, the light receiving element 5 Light emitted from the light emitting element 4 and scattered by smoke is received. Therefore, the smoke detector 1 can detect the smoke present in the smoke detection space Sp <b> 1 depending on the light receiving state of the light receiving element 5. The first cover 21 includes a first surface 21a (upper surface in the examples of FIGS. 6 and 7). The second cover 22 includes a second surface 22a (the lower surface in the examples of FIGS. 6 and 7). The second surface 22a faces the first surface 21a in the reference direction (the vertical direction in the examples of FIGS. 6 and 7). The smoke detection block 10 and the sound output unit 61 are disposed in the housing space Sp2 (see FIG. 8) formed in the housing 2 between the first surface 21a and the second surface 22a.

  In the smoke detector 1, the smoke detection block 10 includes a filter 72 that prevents foreign matters (insects, lint, etc.) from entering the smoke detection space Sp <b> 1 from the external space.

(2) Configuration Hereinafter, the configuration of the smoke detector 1 according to the present embodiment will be described in detail.

  In the present embodiment, as an example, the smoke detector 1 will be described as being attached to the ceiling of a facility. Hereinafter, in the state in which the smoke detector 1 is attached to the ceiling, a direction perpendicular (orthogonal) to the horizontal plane is referred to as “up and down direction”, and a lower direction in the up and down direction is referred to as “down direction”. However, these directions are not intended to limit the use direction (mounting direction) of the smoke detector 1. For example, the “downward” defined here may be the front (horizontal direction) in the actual installation state of the smoke detector 1.

  Moreover, in each drawing demonstrated below, the structure of the smoke detector 1 is typically represented, and the various dimensional relationships in drawing, etc. may differ from a real thing.

(2.1) Overall Configuration First, the overall configuration of the smoke detector 1 according to the present embodiment will be described with reference to FIGS.

  The smoke detector 1 includes a housing 2, a smoke detection block 10 (see FIG. 6), and a sound output unit 61 (see FIG. 6). In the present embodiment, the smoke detector 1 further includes a circuit block 20 (see FIG. 6) and a battery 62. The battery 62 is not necessarily included in the components of the smoke detector 1, and the battery 62 may not be included in the components of the smoke detector 1.

  The housing | casing 2 is disk shape which becomes circular shape in planar view. The housing 2 is a molded product made of synthetic resin. The housing 2 has a first cover 21 and a second cover 22. The first cover 21 is combined with the second cover 22 so as to cover the second surface 22 a of the second cover 22. The second cover 22 is fixed to a construction surface (a ceiling surface in the present embodiment). However, strictly speaking, the second cover 22 is not directly fixed to the construction surface, but is indirectly fixed to the construction surface by being fixed to the mounting base fixed to the construction surface. The

  Here, both the 1st cover 21 and the 2nd cover 22 are formed in disk shape, and the outer periphery shape in planar view is the same. Therefore, the first cover 21 and the second cover 22 are combined to form one disk-shaped housing 2. The first cover 21 is coupled to the second cover 22 by a plurality of (three) screws 63. In a state where the first cover 21 and the second cover 22 are coupled to each other, the smoke detection block 10, the circuit block 20, and the sound output unit 61 are accommodated between the first cover 21 and the second cover 22. .

  The first cover 21 includes a circular first main plate 211 and a first peripheral wall 212 protruding upward from the outer peripheral portion of the upper surface of the first main plate 211. The first cover 21 has a circuit block arrangement region 213 (see FIG. 7) for arranging the circuit block 20 and a first sound output unit for arranging the sound output unit 61 on the upper surface of the first main plate 211. It further has an arrangement region 214 (see FIG. 7). The first cover 21 further has a push button 215 arranged in the circuit block arrangement region 213. The push button 215 is configured to be movable by a hinge structure with respect to the first main plate 211, and can be pushed into the inside of the housing 2, that is, upward. When the push button 215 is pressed, the switches included in the circuit block 20 are operated.

  In the first cover 21, a sound hole 217 (see FIG. 5A) penetrating in the thickness direction of the first main plate 211 is formed in a part of the first main plate 211 corresponding to the first sound output portion arrangement region 214. Is formed.

  The second cover 22 includes a circular second main plate 221 and a second peripheral wall 222 protruding upward from the outer peripheral portion of the upper surface of the second main plate 221. Further, the second cover 22 has a recess 223 (see FIG. 6) for arranging the smoke detection block 10 and a second sound output unit arrangement for arranging the sound output unit 61 on the lower surface of the second main plate 221. A region 224 is further included. The second cover 22 further has a battery housing area 225 (see FIG. 7) for housing the battery 62 on the upper surface of the second main plate 221.

  The second cover 22 further includes a plurality of spacers 226 that protrude downward from the lower surface of the second main plate 221. The plurality of spacers 226 ensure a predetermined gap between the first cover 21 and the second cover 22 by bringing the respective leading end portions (lower end portions) into contact with the upper surface of the first main plate 211. Specifically, in the state where the first cover 21 and the second cover 22 are coupled to each other, the internal space of the housing 2 is defined between the upper end surface of the first peripheral wall 212 and the lower surface of the second main plate 221. A gap is formed as an opening 23 connected to the outside of the housing 2. Thereby, smoke can flow into the internal space of the housing 2, that is, the space between the first cover 21 and the second cover 22 through the opening 23.

  The smoke detection block 10 includes a case 7, a light emitting element 4 (see FIG. 9A), and a light receiving element 5 (see FIG. 9A). The case 7 has a disk shape that is circular in plan view. Case 7 has light shielding properties. In the present embodiment, a part of the case 7 functions as the wall structure 3 (see FIG. 9A). The wall structure 3 has a function of taking smoke into the smoke sensing space Sp1 from the outside of the smoke sensing space Sp1, while suppressing light from entering the smoke sensing space Sp1 from the outside of the smoke sensing space Sp1. The smoke detection block 10 is disposed above the circuit block 20 in the internal space of the housing 2. The smoke detection block 10 detects smoke present in the smoke detection space Sp1 (see FIGS. 8 to 10) in the case 7.

  That is, as shown in FIG. 8, the smoke detection block 10 has a circuit block 20 or the like in an internal space of the housing 2, that is, a space between the first cover 21 and the second cover 22 (accommodating space Sp2 described later). Accommodated with. Since the internal space of the housing 2 is connected to the outside of the housing 2 through the opening 23 as described above, smoke can flow into the internal space of the housing 2 through the opening 23. In FIG. 8, a part of the smoke entry path is schematically indicated by a dotted arrow. The smoke detection block 10 has the wall structure 3 that takes smoke into the smoke detection space Sp1 from the outside of the smoke detection space Sp1, so that the smoke that has flowed into the internal space (housing space Sp2) of the housing 2 is further detected. It becomes possible to flow into the space Sp1. Thereby, smoke can be detected by the smoke detection block 10. The smoke detection block 10 will be described in detail in the section “(2.3) Configuration of the smoke detection block”.

  The circuit block 20 includes a printed wiring board 201 and a plurality of electronic components 202 including switches. The plurality of electronic components 202 are mounted on the printed wiring board 201. The light emitting element 4 and the light receiving element 5 of the smoke sensing block 10 are electrically connected to the conductor portion of the printed wiring board 201. Further, the sound output unit 61 and the battery 62 are further electrically connected to the conductor portion of the printed wiring board 201. In the present embodiment, the printed wiring board 201 is disposed below the smoke detection block 10, that is, between the smoke detection block 10 and the first main plate 211. The smoke detection block 10 is mounted on one surface (upper surface) of the printed wiring board 201 in the thickness direction.

  Here, the circuit block 20 includes a control circuit composed of a plurality of electronic components 202. The control circuit is a circuit that controls the light emitting element 4, the light receiving element 5, the sound output unit 61, and the like, drives at least the light emitting element 4, and executes signal processing on the output signal of the light receiving element 5. In the signal processing, the circuit block 20 determines the presence or absence of smoke in the smoke sensing space Sp1 by comparing the amount of light received by the light receiving element 5 (the magnitude of the output signal) with a threshold value. The amount of light received by the light receiving element 5 varies depending on, for example, the smoke concentration in the smoke sensing space Sp1 and the type of smoke (white smoke, black smoke, etc.). Therefore, the circuit block 20 determines that “smoke is present” when smoke having a certain concentration or more exists in the smoke sensing space Sp1 by comparison with the threshold value. When detecting the presence of smoke, the circuit block 20 outputs an electrical signal for driving the sound output unit 61 to the sound output unit 61.

  The sound output unit 61 receives an electric signal from the circuit block 20 and outputs a sound (sound wave). The sound output unit 61 is realized by a speaker or a buzzer that converts an electrical signal into sound. The sound output unit 61 has a disk shape that is circular in plan view. The sound output unit 61 is driven according to the state of the smoke detector 1, and the smoke detector 1 outputs a sound from the sound output unit 61 at least when the presence of smoke is detected.

  The battery 62 is housed in the battery housing region 225 above the second cover 22. The battery 62 may be either a primary battery or a secondary battery.

  The smoke detector 1 according to the present embodiment configured as described above is included in, for example, a component of an automatic fire alarm system. In addition to the smoke detector 1, the automatic fire alarm system, for example, a receiver that receives an alarm signal (fire signal) from the smoke detector 1, and a button for operating a push button when a person detects a fire. Equipped with a transmitter. In the automatic fire alarm system, for example, when the smoke detector 1 detects the occurrence of a fire (due to smoke), a notification signal (fire signal) is sent from the smoke detector 1 to the receiver to notify the fire occurrence. Is done.

(2.2) Structure of the Case The upper surface 22b of the second cover 22 is provided with a plurality of hook portions 229 as an attachment structure for attaching the case 2 to the construction surface (ceiling surface in the present embodiment). Yes. The plurality of hook portions 229 are arranged along the outer peripheral edge of the upper surface 22b and protrude upward from the upper surface 22b. The second cover 22 is fixed to the mounting base by hooking the plurality of hook portions 229 to the mounting base, and thereby the housing 2 is indirectly fixed to the construction surface.

  More specifically, the outer peripheral surface 24 of the housing 2 is formed by the first peripheral wall 212 of the first cover 21 and the second peripheral wall 222 of the second cover 22, and the first peripheral wall 212 and the second peripheral wall 222 are A gap formed between the two forms an opening 23. The opening 23 is located substantially at the center of the outer peripheral surface 24 of the housing 2 in the reference direction (vertical direction), and is formed over the entire periphery of the outer peripheral surface 24. Thereby, the smoke detector 1 can flow smoke into the internal space (accommodation space Sp2) of the housing 2 from the entire circumferential direction of the outer peripheral surface 24 while keeping the size of the opening 23 in the reference direction relatively small. This makes it easier for smoke to enter.

  Further, in the smoke detector 1 according to the present embodiment, the smoke detection block 10 and the sound output unit 61 are accommodated together in the accommodation space Sp2, so that the sound output unit 61 for the smoke detection space Sp1 of the smoke detection block 10 is output. In order to reduce the influence of the sound to be played, the following configuration is adopted. That is, the smoke detector 1 further includes a partition wall 25. The partition wall 25 is disposed around the sound output unit 61 in the accommodation space Sp2 so as to surround the sound output unit 61 in a plan view (viewed from one side in the reference direction). As shown in FIG. 7, the partition wall 25 is integrated with the first main plate 211 so as to protrude upward from the periphery of the first sound output portion arrangement region 214 on the first surface 21 a (the upper surface of the first main plate 211). Is formed.

  Furthermore, in the present embodiment, the second cover 22 has a boss portion 228 (see FIG. 6) for pressing the sound output portion 61. The boss portion 228 is, for example, cylindrical and protrudes downward from the second surface 22a (the lower surface of the second main plate 221). In a state where the first cover 21 and the second cover 22 are coupled to each other, the boss portion 228 has a tip portion (lower end portion) that contacts the sound output portion 61 and presses the sound output portion 61 against the first surface 21a. .

  In the present embodiment, the second cover 22 has a plurality of guide walls 26 for guiding smoke to the smoke sensing space Sp1. As shown in FIG. 6, the plurality of guide walls 26 protrude downward from the second surface 22 a (the lower surface of the second main plate 221). The plurality of guide walls 26 are formed in a shape extending substantially radially from the center of the region (the recessed portion 223) where the smoke detection block 10 is disposed in a plan view. The plurality of guide walls 26 cause smoke flowing into the internal space (accommodating space Sp2) of the casing 2 from the opening 23 of the outer peripheral surface 24 of the casing 2 to be smoke of the smoke detection block 10 disposed in the accommodating space Sp2. Guide to the sensing space Sp1. Smoke generated at the time of a fire usually has a property of flowing upward, so that a plurality of guide walls 26 are formed on the second surface 22a which is the upper surface of the accommodation space Sp2, so that the smoke enters the smoke sensing space Sp1. It becomes easy to be induced.

  Here, a convex portion 230 having a shape corresponding to the battery housing region 225 is formed on a portion of the second surface 22a on the back side of the battery housing region 225 (see FIG. 7). A part of the plurality of guide walls 26 includes a connecting piece 261 connected to the convex portion 230. Accordingly, the plurality of guide walls 26 can efficiently guide smoke even in the internal space (accommodating space Sp2) of the housing 2 from the convex portion 230 toward the smoke sensing space Sp1.

(2.3) Configuration of Smoke Detection Block Next, a more detailed configuration of the smoke detection block 10 will be described with reference to FIGS. 9A and 10. However, each drawing described below is a schematic diagram, and the length or size ratio of each part in the drawing does not necessarily reflect the actual dimensional ratio.

  As described above, the smoke detection block 10 includes the case 7, the light emitting element 4, and the light receiving element 5, and a part of the case 7 functions as the wall structure 3. Inside the case 7, a smoke sensing space Sp1 is formed. The case 7 includes a light emitting element holder 8 that holds the light emitting element 4. Further, the case 7 has a light receiving element holder 9 that holds the light receiving element 5. That is, the smoke detector 1 according to the present embodiment includes a light emitting element holder 8 and a light receiving element holder 9.

  In the present embodiment, as shown in FIG. 9A, the case 7 has a case main body 71 and a filter 72. The case body 71 is a molded product made of synthetic resin. The filter 72 is a synthetic resin molded product. The filter 72 is combined with the case main body 71 so as to cover the upper surface of the case main body 71. The case body 71 is fixed to the printed wiring board 201 (see FIGS. 6 and 7). The case main body 71 has a pair of claws 711 (see FIGS. 9A and 10) for fixing the case main body 71 to the printed wiring board 201. The pair of claws 711 protrude downward from the outer peripheral portion of the lower surface of the case main body 71, and the case main body 71 is fixed to the printed wiring board 201 by being caught on the periphery of the hole of the printed wiring board 201. In other words, the case main body 71 and the printed wiring board 201 are mechanically coupled by a snap fit method.

  Here, the case main body 71 and the filter 72 are both formed in a circular shape in plan view, and the outer peripheral shape in plan view is substantially the same. Therefore, the case main body 71 and the filter 72 are combined to form one disc-shaped case 7. The case main body 71 has a pair of claws 712 (see FIGS. 9A and 10) for connecting the case main body 71 and the filter 72. The pair of claws 712 protrude upward from the outer peripheral portion of the upper surface of the case main body 71, and are coupled to the case main body 71 and the filter 72 by being hooked on the outer peripheral surface of the filter 72. In other words, the case body 71 and the filter 72 are mechanically coupled by a snap fit method. In a state where the case main body 71 and the filter 72 are coupled to each other, a smoke sensing space Sp1 is formed between the case main body 71 and the filter 72.

  The case main body 71 includes a circular bottom plate 73 and a wall structure 3 protruding upward from the outer peripheral portion of the upper surface 731 of the bottom plate 73. The upper surface 731 of the bottom plate 73 constitutes the bottom surface of the smoke sensing space Sp1. The case body 71 further includes a light emitting element holder 8 and a light receiving element holder 9. Here, the case main body 71 also serves as an optical base. The case body 71 further includes a light shielding wall 74 (see FIG. 10), a light shielding rib 75 (see FIG. 10), and an auxiliary light shielding wall 76 (see FIG. 10). Each of the light emitting element holder 8, the light receiving element holder 9, the light shielding wall 74, the light shielding rib 75, and the auxiliary light shielding wall 76 protrudes upward from the upper surface 731 of the bottom plate 73. Here, the protruding amounts of the light emitting element holder 8, the light receiving element holder 9, the light blocking wall 74 and the auxiliary light blocking wall 76 from the upper surface 731 of the bottom plate 73 are substantially the same as the protruding amounts of the wall structure 3 from the upper surface 731 of the bottom plate 73. is there.

  The filter 72 includes a circular upper plate 721 and a peripheral wall 722 that protrudes downward from the outer peripheral portion of the lower surface of the upper plate 721. The inner diameter of the peripheral wall 722 is larger than the outer diameter of the wall structure 3. Further, the protruding amount of the peripheral wall 722 from the lower surface of the upper plate 721 is substantially the same as the protruding amount of the wall structure 3 from the upper surface 731 of the bottom plate 73. Therefore, in a state where the case main body 71 and the filter 72 are coupled to each other, the distal end surface (lower end surface) of the peripheral wall 722 contacts the upper surface 731 of the bottom plate 73, and the distal end surface (upper end surface) of the wall structure 3 is the upper plate 721. Touch the lower surface of the. In this state, the wall structure 3 is accommodated in a space surrounded by the peripheral wall 722.

  The peripheral wall 722 includes a plurality of filter parts 723. Each of the plurality of filter portions 723 has a plurality of openings 7231. Each of the plurality of filter portions 723 includes a plurality of linear portions 7232 positioned between two adjacent openings 7231 among the plurality of openings 7231. The opening shape of each of the plurality of openings 7231 is, for example, a square shape. The plurality of filter parts 723 are arranged along the circumferential direction of the lower surface of the upper plate 721. The filter 72 reduces entry of foreign matters such as insects and lint from the external space into the smoke sensing space Sp1 in the case 7.

  As shown in FIG. 10, the wall structure 3 surrounds the smoke sensing space Sp1 when viewed from one direction (upward) orthogonal to the upper surface 731 (one plane) of the bottom plate 73. FIG. 10 is a plan view of the smoke detection block 10 with the filter 72 removed from the case body 71, that is, with the filter 72 omitted. In the present embodiment, a circular smoke sensing space Sp <b> 1 is formed on the upper surface 731 of the bottom plate 73 in a plan view. The wall structure 3 is formed in an annular shape so as to surround the smoke sensing space Sp1 in a plan view. In other words, an annular wall structure 3 is formed on the outer peripheral portion of the upper surface 731 of the bottom plate 73 along the outer peripheral edge of the upper surface 731. In a state where the case main body 71 and the filter 72 are coupled to each other, a space between the bottom plate 73 and the upper plate 721 and surrounded by the wall structure 3 becomes the smoke sensing space Sp1. That is, the smoke sensing space Sp1 and the space around the smoke sensing space Sp1 are partitioned by the wall structure 3.

  The wall structure 3 has a function of suppressing light transmission while allowing smoke to pass therethrough. Thereby, the wall structure 3 can take in smoke from the outside of the smoke sensing space Sp1 into the smoke sensing space Sp1, while suppressing light from entering the smoke sensing space Sp1 from the outside of the smoke sensing space Sp1. To do.

  Such a wall structure 3 has a plurality of smoke passage holes 33 in order to realize the above function. The plurality of smoke passage holes 33 are arranged along the circumferential direction of the wall structure 3. Thereby, the wall structure 3 can allow smoke to pass through each smoke passage hole 33, and allows the smoke to be taken into the smoke sensing space Sp1 from the outside of the smoke sensing space Sp1. Here, each smoke passage hole 33 has a shape in which at least a part is bent. That is, from the outside of the wall structure 3, each smoke passage hole 33 is at least partially curved or curved so that the smoke sensing space Sp <b> 1 surrounded by the wall structure 3 cannot be seen through the smoke passage holes 33. It has a bent shape. As a result, the wall structure 3 is inhibited from transmitting light through the wall structure 3 through each smoke passage hole 33, and light can be prevented from entering the smoke sensing space Sp1 from the outside of the smoke sensing space Sp1. .

  Specifically, the wall structure 3 is an aggregate of a plurality of small pieces 30 arranged along the outer peripheral edge of the upper surface 731. The wall structure 3 allows smoke to pass between the plurality of small pieces 30. In other words, on the outer peripheral portion of the upper surface 731 of the bottom plate 73, a plurality of small pieces 30 are arranged along the outer peripheral edge of the upper surface 731 at intervals. Each of the plurality of small pieces 30 protrudes from the upper surface 731 of the bottom plate 73 and constitutes one wall structure 3. The amount of protrusion of the plurality of small pieces 30 from the upper surface 731 is substantially uniform. The wall structure 3 has smoke passing holes 33 between a pair of adjacent small pieces 30 among the plurality of small pieces 30. Therefore, the small pieces 30 constituting the wall structure 3 do not exist on both sides of each smoke passage hole 33 in the vertical direction.

  In the present embodiment, each of the plurality of small pieces 30 is formed in a substantially L shape, a substantially V shape, or a substantially Y shape in plan view. With such a shape, each smoke passage hole 33 formed by a gap formed between a pair of adjacent small pieces 30 has a shape in which at least a part is bent in a plan view as described above.

  In the present embodiment, as an example, the light emitting element 4 is a light emitting diode. More specifically, the light emitting element 4 is a light emitting diode with a lens. The light emitting element 4 has a pair of lead wires 402 and is electrically connected to the printed wiring board 201. The light emitting element 4 emits light upon receiving power supply from the circuit block 20. Thereby, the light emitting element 4 radiates | emits light toward smoke detection space Sp1.

  The light receiving element 5 is an element that performs photoelectric conversion for converting light into an electrical signal. In the present embodiment, as an example, the light receiving element 5 is a photodiode. More specifically, the light receiving element 5 is a photodiode with a lens. The light receiving element 5 has a pair of lead wires 502 and is electrically connected to the printed wiring board 201. The light receiving element 5 is electrically connected to the circuit block 20.

  Here, the light receiving element 5 is arranged at a position where the direct light from the light emitting element 4 does not enter and the scattered light from the smoke in the smoke sensing space Sp1 enters. That is, both the light emitting element 4 and the light receiving element 5 are arranged toward the smoke sensing space Sp1. However, as shown in FIG. 10, a light shielding wall 74 is arranged on a straight line connecting the light emitting element 4 and the light receiving element 5 in plan view. The light blocking wall 74 has a function of blocking direct light from the light emitting element 4 to the light receiving element 5. In the present embodiment, the light shielding wall 74 is formed in a shape that is continuous with one of the plurality of small pieces 30 constituting the wall structure 3. FIG. 10 is a plan view of the smoke sensing block 10 with the filter 72 removed, that is, with the filter 72 omitted.

  The light emitting element 4 and the light receiving element 5 are arranged in a positional relationship such that the optical axis A4 of the light emitting element 4 and the optical axis A5 of the light receiving element 5 intersect each other in plan view. If the light emitting element 4 and the light receiving element 5 are in the positional relationship as described above, direct light from the light emitting element 4 does not enter the light receiving element 5. On the other hand, when smoke flows into the smoke sensing space Sp1, the light from the light emitting element 4 exists in the overlapping range between the light irradiation range of the light emitting element 4 and the light receiving range of the light receiving element 5 in the smoke sensing space Sp1. The light receiving element 5 receives at least a part of the scattered light.

  As described above, in a state where no smoke exists in the smoke sensing space Sp1, the light receiving element 5 does not receive light emitted from the light emitting element 4, and in a state where smoke exists in the smoke sensing space Sp1, the light receiving element 5 The light (scattered light) emitted from the light emitting element 4 and scattered by the smoke is received. Therefore, the smoke detector 1 can detect the smoke present in the smoke detection space Sp <b> 1 depending on the light receiving state of the light receiving element 5.

  Further, the light shielding rib 75 is disposed at a position facing the light emitting surface of the light emitting element 4 in plan view. A certain gap is generated between the light shielding rib 75 and the filter 72. The optical axis A4 of the light emitting element 4 passes through the gap above the light shielding rib 75. Thus, the light shielding rib 75 suppresses the spread of light emitted from the light emitting element 4 in the vertical direction.

  The auxiliary light shielding wall 76 is formed in a shape that is continuous with one small piece 30 located between the light shielding wall 74 and the light receiving element holder 9 among the plurality of small pieces 30 constituting the wall structure 3. The auxiliary light shielding wall 76 suppresses the generation of stray light inside the smoke sensing space Sp1 due to reflection of light on the upper surface 731 of the bottom plate 73 or the lower surface of the upper plate 721, and smoke into the smoke sensing space Sp1. It has a function to improve the inflow property. That is, the auxiliary light shielding wall 76 is a separate structure from the small piece 30 that is a part of the wall structure 3 for suppressing light from entering the smoke sensing space Sp1 from the outside of the smoke sensing space Sp1. In FIG. 10, the boundary line between the auxiliary light shielding wall 76 and the small piece 30 is indicated by an imaginary line (two-dot chain line).

  The light emitting element holder 8 holds the light emitting element 4. The light emitting element holder 8 is disposed between two small pieces 30 among the plurality of small pieces 30 constituting the wall structure 3. The light emitting element holder 8 has a recess in which the light emitting element 4 is fitted. The light emitting element holder 8 has a function of positioning the light emitting element 4.

  The light receiving element holder 9 holds the light receiving element 5. The light receiving element holder 9 is arranged between two small pieces 30 among the plurality of small pieces 30 constituting the wall structure 3. The light receiving element holder 9 has a recess in which the light receiving element 5 is fitted.

(2.4) Filter and Manufacturing Method Thereof The filter 72 includes a plurality of filter parts 723 as shown in FIG. 9A. Each of the plurality of filter portions 723 has a plurality of openings 7231 as shown in FIG. 9B. The plurality of openings 7231 are arranged in a matrix. Each of the plurality of filter portions 723 includes a plurality of linear portions 7232 positioned between two adjacent openings 7231 among the plurality of openings 7231. Further, the filter portion 723 has a frame portion 726 (see FIG. 3) surrounding the plurality of openings 7231 and the plurality of linear portions 7232. The frame part 726 has a rectangular frame shape. The opening shape of each of the plurality of openings 7231 is, for example, a square shape. The plurality of filter parts 723 are arranged along the circumferential direction of the lower surface of the upper plate 721.

  The filter 72 has a function of suppressing foreign substances (insects, lint, etc.) from entering the smoke sensing space Sp1 from the external space. Here, the opening size of the plurality of openings 7231 is, for example, 0.3 mm × 0.3 mm. Further, the line width of each of the plurality of linear portions 7232 is, for example, 0.1 mm or less, for example, 0.07 mm. In the present embodiment, the filter 72 has a light shielding property. The filter 72 has electrical insulation.

  In the present embodiment, each of the plurality of linear portions 7232 has a substantially elliptical cross-sectional shape orthogonal to the longitudinal direction. In the present embodiment, the line width L2 of each of the plurality of linear portions 7232 is the length L1 in the shortest axial direction in the cross section orthogonal to the length direction of the linear portions 7232 (see FIG. 2B). Therefore, in this embodiment, each of the plurality of linear portions 7232 has a length L1 in the shortest axial direction in a cross section orthogonal to the length direction of 0.1 mm or less, for example, 0.07 mm.

  The filter 72 includes a three-dimensionally shaped body 13 (see FIGS. 1B and 1C) formed using the first molded body 11 (see FIGS. 1A, 2A and 2B) having the plurality of filter portions 723, and a second molded body. 12 (see FIG. 1C). The first molded body 11 is a resin molded body. The material of the first molded body 11 includes, for example, a liquid crystal polymer (LCP). The material of the 1st molded object 11 is not restricted to a liquid crystal polymer, For example, a polypropylene (PP), a polyethylene-type resin, etc. may be sufficient. The second molded body 12 is a resin molded body. The material of the second molded body 12 includes, for example, polycarbonate ABS. The material of the 2nd molded object 12 is not restricted to polycarbonate ABS, For example, a liquid crystal polymer, a polypropylene, etc. may be sufficient. In the present embodiment, the material of the first molded body 11 and the material of the second molded body 12 are different, but the material of the first molded body 11 and the material of the second molded body may be the same. In addition, although the material of the 1st molded object 11 and the material of the 2nd molded object 12 contain the black pigment, it is not restricted to this, For example, you may contain the white pigment instead of the black pigment.

  The first molded body 11 includes a plurality of filter portions 723 arranged in the circumferential direction and a disk-shaped connection portion 725 to which the plurality of filter portions 723 are connected. The disk shape with respect to the connecting portion 725 is a substantially disk shape. The substantially disk shape is not limited to a circular shape when viewed from the thickness direction, and includes, for example, a regular polygon shape having six or more corners. In the present embodiment, the connecting portion 725 has an equilateral triangular shape. Further, in the present embodiment, the first molded body 11 includes a protruding portion 724 that is located between two filter portions 723 that are separated from each other in the circumferential direction among the plurality of filter portions 723 and is connected to the connecting portion 725. . The plurality of filter portions 723 and the protruding portions 724 protrude outward of the connecting portion 725 in the same plane as the connecting portion 725. In short, in the first molded body 11, the plurality of filter parts 723 and the protruding parts 724 extend radially from the connecting part 725 in plan view. Each of the plurality of filter portions 723 and the protruding portions 724 has a substantially rectangular shape.

  In the three-dimensionally shaped body 13, the plurality of filter parts 723 are bent at the boundary with the connecting part 725 in the first molded body 11. The plurality of filter parts 723 are bent so that the angle formed with the connecting part 725 is approximately 90 degrees.

  The second molded body 12 is formed integrally with the three-dimensional shape body 13. The filter 72 includes the cylindrical body 14 that includes the three-dimensionally shaped body 13 and the second molded body 12 and includes a plurality of filter portions 723 as part of the side wall 141.

  Hereinafter, the manufacturing method of the filter 72 is demonstrated based on FIG.

  The method for manufacturing a filter includes a first step, a second step, and a third step.

  In the first step, the first molded body 11 including a plurality of filter parts 723 and one connecting part 725 is injection-molded (see FIGS. 1A and 3). The filter portion 723 includes a plurality of openings 7231 and a plurality of linear portions 7232 each positioned between two adjacent openings 7231 among the plurality of openings 7231. A plurality of filter parts 723 are connected to the connection part 725. In the present embodiment, the projecting portion 724 is connected to the connecting portion 725.

  In the first step, as shown in FIG. 3, for example, a molding resin (molten resin) is connected to each of a plurality of runners (Runner) R1 and a plurality of runners R1 in a mold. It supplies to the cavity corresponding to the 1st molded object 11 through the gate G1. The plurality of gates G1 are arranged side by side in the circumferential direction. The plurality of gates G <b> 1 are arranged in the mold in the periphery of the cavity, i.e., closer to the cavity corresponding to the filter part 723 than the center of the cavity corresponding to the connecting part 725. The plurality of gates G1 are connected so as to be substantially orthogonal to the cavities corresponding to the connecting portions 725. The through direction of the plurality of openings 7231 in each of the plurality of filter portions 723 is a direction along the thickness direction of the connecting portion 725. More specifically, the through direction of the plurality of openings 7231 in each of the plurality of filter portions 723 is a direction parallel to the thickness direction of the connecting portion 725.

  In the second step, the three-dimensional body 13 is formed by bending the first molded body 11 at the boundary between the filter portion 723 and the connecting portion 725 (see FIG. 1B).

  In the third step, the cylindrical body 14 including the filter portion 723 as a part of the side wall (the peripheral wall 722 of the filter 72) is formed by integrally molding the second molded body 12 into the three-dimensionally shaped body 13 by resin molding ( (See FIG. 1C). In the third step, the second molded body 12 is molded by an injection molding method. However, the present invention is not limited to this. For example, the second molded body 12 may be molded by cast molding.

  The second molded body 12 includes a first reinforcing part 121 and a plurality of second reinforcing parts 122. The first reinforcing part 121 is bonded to the connecting part 725. More specifically, the first reinforcing part 121 is formed so as to overlap the connecting part 725 and reinforces the three-dimensionally shaped body 13. The 1st reinforcement part 121 is disk shape. Each of the plurality of second reinforcing portions 122 overlaps a part of the filter part 723 and a part of the filter part 723 or the protruding part 724 adjacent to the filter part 723 in the three-dimensionally shaped body 13 so as not to overlap the opening 7231. The solid body 13 is reinforced by being bonded to both. The 2nd reinforcement part 122 is columnar. The cylindrical body 14 includes a plurality of filter portions 723, projecting portions 724, and a plurality of second reinforcing portions 122.

  In the filter manufacturing method of the present embodiment, the thickness of at least a part of the second molded body 12 is thicker than the thickness of the first molded body 11. The thickness of the 1st molded object 11 is 0.05 mm-0.1 mm in the filter part 723, for example. The thickness of the second molded body 12 is, for example, 1 mm to 2 mm.

  As shown in FIG. 4, each of the plurality of linear portions 7232 is elongated in a prescribed direction along the penetrating direction of the corresponding two openings 7231 among the plurality of openings 7231. In the present embodiment, both ends in the prescribed direction of each of the plurality of linear portions 7232 are tapered. In FIG. 4, a part of the smoke entry path is schematically indicated by a dotted arrow.

(3) Effect The method for manufacturing a filter according to Embodiment 1 includes a first step, a second step, and a third step. In the first step, the first molded body 11 including the filter portion 723 and the connecting portion 725 is injection molded. The filter portion 723 includes a plurality of openings 7231 and a plurality of linear portions 7232 each positioned between two adjacent openings 7231 among the plurality of openings 7231. A filter portion 723 is connected to the connecting portion 725. In the second step, the three-dimensional body 13 is formed by bending the first molded body 11 at the boundary between the filter portion 723 and the connecting portion 725. In the third step, the cylindrical body 14 including the filter portion 723 as a part of the side wall 141 is formed by integrally molding the second molded body 12 into the three-dimensionally shaped body 13 by resin molding.

  Thereby, in the manufacturing method of the filter concerning Embodiment 1, a plurality of openings 7231 can be formed along the thickness direction of filter part 723, and it becomes possible to improve filter performance. In the filter manufacturing method according to the first embodiment, it is possible to suppress the occurrence of defects such as flashes and unfilled portions in the filter unit 723.

  The smoke detector 1 according to the first embodiment includes a filter 72 that prevents foreign matter from entering the smoke detection space Sp1 from the external space. The filter 72 includes the three-dimensionally shaped body 13 and the second molded body 12. In the three-dimensionally shaped body 13, the plurality of filter parts 723 in the first molded body 11 including a plurality of filter parts 723 arranged in the circumferential direction and a disk-shaped connecting part 725 connected to the plurality of filter parts 723. It is bent at the boundary with the connecting portion 725. Each of the plurality of filter portions 723 has a plurality of openings 7231. The second molded body 12 is formed integrally with the three-dimensional shape body 13. The filter 72 includes the cylindrical body 14 that includes the three-dimensionally shaped body 13 and the second molded body 12 and includes a plurality of filter portions 723 as part of the side wall 141.

  Thereby, in the smoke detector 1 according to the first embodiment, it is possible to improve the filter performance. Therefore, the smoke detector 1 can suppress the occurrence of direction dependency in the smoke detection characteristics. Moreover, the smoke detection capability of the smoke detector 1 can be improved.

(4) Modification The smoke detector 1 according to the embodiment is only one of various embodiments of the present disclosure. The smoke detector 1 according to the embodiment can be variously changed according to the design or the like as long as the object of the present disclosure can be achieved. Hereinafter, modifications of the embodiment will be listed. The modifications described below can be applied in appropriate combinations.

  For example, in the embodiment, the case 7 and the smoke sensing space Sp1 are both circular in a plan view. However, the present invention is not limited to this configuration, and the case 7 or the smoke sensing space Sp1 is, for example, in a plan view. It may be oval or polygonal. In this case, the wall structure 3 also has an elliptical shape or a polygonal shape in plan view.

  Further, the smoke detector 1 is not limited to the configuration in which the light receiving element 5 receives the radiated light from the light emitting element 4 scattered by the smoke flowing into the smoke sensing space Sp1. In the smoke detector 1, for example, a light receiving element 5 is disposed at a position where direct light from the light emitting element 4 is incident, and a change in the light receiving state in the light receiving element 5 due to smoke flowing into the smoke sensing space Sp1 (decrease in received light amount). ), The smoke present in the smoke sensing space Sp1 may be sensed.

  In the embodiment, the plurality of small pieces 30 are formed integrally with the bottom plate 73 so as to protrude from the upper surface 731 of the bottom plate 73. However, the present invention is not limited to this configuration, and the plurality of small pieces 30 are separate from the bottom plate 73. There may be. For example, the plurality of small pieces 30 may be fixed to the bottom plate 73 by adhesion or fitting. In this case, the plurality of small pieces 30 exist separately, but even in this case, the plurality of small pieces 30 constitute one wall structure 3.

  Although the 1st molded object 11 has the several filter part 723, the number of the filter parts 723 is not restricted to plural, and may be one. Moreover, although the 1st molded object 11 has the protrusion part 724, the structure which is not provided with the protrusion part 724 may be sufficient. Further, the number and arrangement of the filter parts 723 and the protrusions 724 in the first molded body 11 are not limited to the example of FIG. 1A, and for example, a plurality of filter parts 723 and a plurality of protrusions 724 may be alternately arranged. Good.

  Further, each of the plurality of linear portions 7232 is not limited to the case where the cross-sectional shape orthogonal to the length direction is a substantially elliptical shape, and the cross-sectional shape orthogonal to the length direction is circular, trapezoidal, etc. It may be. Therefore, each of the plurality of linear portions 7232 is not limited to a shape in which both ends in the specified direction are tapered.

  In addition, each of the plurality of linear portions 7232 may have a minute protrusion formed between an intermediate portion in the prescribed direction and an end on the downstream side of the gas flow in the prescribed direction. Thereby, generation | occurrence | production of a vortex can be suppressed and it becomes possible to reduce a pressure loss. Since the linear portion 7232 of the filter 72 includes such a protrusion, pressure loss when smoke passes through the filter 72 of the smoke detector 1 can be reduced, and smoke inflow characteristics can be improved. Therefore, the smoke detector 1 can improve the smoke detection capability.

  Further, the opening shape of the plurality of openings 7231 in the filter unit 723 is not limited to a square shape, and may be, for example, a rectangular shape, a hexagonal shape, a circular shape, or the like. The plurality of openings 7231 are not limited to being arranged in a matrix, and may be arranged in a honeycomb, for example. In the filter portion 723, a plurality of types of opening portions 7231 having different opening shapes may be mixed.

  Further, the filter 72 may be configured to be applied to other than the smoke detector 1. For example, the filter may be a ventilation filter, a medical filter, a water purification filter, or the like.

(Embodiment 2)
In the filter manufacturing method according to the present embodiment, the shape of the first molded body 11a (see FIG. 11) that is injection-molded in the first step is the shape that is injection-molded in the first step of the filter manufacturing method according to the first embodiment. This is different from the shape of one molded body 11. Hereinafter, the same configurations as those of the first embodiment are denoted by common reference numerals, and the description thereof is omitted as appropriate. In addition, description of steps similar to those in Embodiment 1 will be omitted as appropriate.

  The first molded body 11a has one fewer filter parts 723 than the first molded body 11 in the first embodiment. In the first molded body 11a, a fan-shaped notch 7251 is formed in the connecting portion 725.

  In the second step, the three-dimensional body similar to the three-dimensional body 13 is formed by bending the filter portion 723 and the protruding portion 724 at the boundary with the connecting portion 725 as in the first embodiment.

  In the third step, similarly to the first embodiment, a second molded body similar to the second molded body 12 is formed integrally with the three-dimensionally shaped body.

  In the present embodiment, in the second step, it is also possible to form a conical three-dimensional body having an open bottom by bending the connecting portion 725 so as to eliminate the gap of the notch 7251 of the connecting portion 725.

  The filter manufactured by the filter manufacturing method of the present embodiment may be applied in place of the filter 72 of the smoke detector 1 of the first embodiment.

(Embodiment 3)
In the filter manufacturing method according to the present embodiment, the shape of the first molded body 11b (see FIG. 12A) to be injection-molded in the first step is the same as that of the first step of the filter manufacturing method according to the first embodiment. This is different from the shape of one molded body 11. Hereinafter, the same configurations as those of the first embodiment are denoted by common reference numerals, and the description thereof is omitted as appropriate. In addition, description of steps similar to those in Embodiment 1 will be omitted as appropriate.

  In the 1st molded object 11b, the shape of the connection part 725 differs from the shape of the connection part 725 of the 1st molded object 11 in Embodiment 1. FIG. The connecting portion 725 in the first molded body 11b has an annular shape.

  In the second step, as in the first embodiment, the three-dimensionally shaped body 13b is formed by bending the filter portion 723 and the protruding portion 724 at the boundary with the connecting portion 725b (see FIG. 12B).

  In the third step, the second molded body 12 is formed integrally with the three-dimensionally shaped body 13b (see FIG. 12C).

  The filter 72b manufactured by the filter manufacturing method of the present embodiment may be applied in place of the filter 72 of the smoke detector 1 of the first embodiment.

(Embodiment 4)
In the filter manufacturing method according to the present embodiment, the shape of the first molded body 11c (see FIGS. 13A and 13B) to be injection-molded in the first step is the injection molding in the first step of the filter manufacturing method according to the first embodiment. It differs from the shape of the 1st molded object 11 to do. Hereinafter, the same configurations as those of the first embodiment are denoted by common reference numerals, and the description thereof is omitted as appropriate. In addition, description of steps similar to those in Embodiment 1 will be omitted as appropriate.

  The first molded body 11c includes a plurality of (two in the illustrated example) filter portions 723c. In the first molded body 11c, a plurality of filter portions 723c are arranged in one direction, and a joint portion 725c common to the two filter portions 723c is interposed between two filter portions 723c adjacent in the one direction. ing.

  In the second step, the three-dimensionally shaped body 13c is formed by bending the first molded body 11c at each boundary between the plurality of filter parts 723c and the connecting parts 725c (see FIG. 14). In the present embodiment, the three-dimensionally shaped body 13c is formed by the two first molded bodies 11c. However, the present invention is not limited to this, and the three-dimensionally shaped body 13 is formed by one first molded body 11c by increasing the number of filter parts 723c. It may be formed.

  In the third step, the bottomed cylindrical body including the plurality of filter portions 723 as part of the side wall is formed by integrally molding the second molded body into the three-dimensionally shaped body 13c by resin molding.

(Summary)
The following aspects are disclosed from the embodiments and the like described above.

  The filter manufacturing method according to the first aspect includes a first step, a second step, and a third step. In the first step, the first molded body (11; 11a; 11b; 11c) including the filter portion (723; 723c) and the connecting portion (725; 725b; 725c) is injection-molded. The filter portion (723; 723c) includes a plurality of linear portions (7232) each positioned between a plurality of openings (7231) and two adjacent openings (7231) among the plurality of openings (7231). Have The connecting portion (725; 725b; 725c) is connected to the filter portion (723; 723c). In the second step, the first molded body (11; 11a; 11b; 11c) is bent at the boundary between the filter portion (723; 723c) and the connecting portion (725; 725b; 725c) to thereby form a three-dimensionally shaped body (13; 13c). ). In the third step, the second molded body (12) is integrally molded into a three-dimensional body (13; 13c) by resin molding, thereby including a filter portion (723; 723c) as a part of the side wall (141). Form body (14).

  The filter manufacturing method according to the first aspect can improve the filter performance.

  In the filter manufacturing method according to the second aspect, in the first aspect, each of the plurality of linear portions (7232) has a length (L1) in the shortest axial direction in a cross section perpendicular to the length direction of 0. .1 mm or less.

  In the filter manufacturing method according to the third aspect, in the first or second aspect, the thickness of at least a part of the second molded body (12) is thicker than the thickness of the first molded body (11).

  In the filter manufacturing method according to the third aspect, the three-dimensionally shaped body (13; 13c) can be reinforced by the second molded body (12), so that the first molded body (11; 11a; 11b; 11c) It becomes possible to make the wall thickness thinner.

  In the filter manufacturing method according to the fourth aspect, in any one of the first to third aspects, the connecting portion (725) of the first molded body (11; 11a) is disk-shaped. The first molded body (11; 11a) includes a plurality of filter portions (723), and the plurality of filter portions (723) are arranged in the circumferential direction of the connecting portion (725). In the second step, the three-dimensionally shaped body (13) is formed by bending the first molded body (11; 11a) at each boundary between the plurality of filter parts (723) and the connecting part (725). In the third step, the second molded body (12) is molded integrally with the three-dimensional shaped body (13) by resin molding to thereby form a cylindrical body (including a plurality of filter parts (723) as a part of the side wall (141) ( 14).

  In the filter manufacturing method according to the fourth aspect, the bottomed cylindrical filter (72) can be easily formed while improving the filter performance.

  In the filter manufacturing method according to the fifth aspect, in any one of the first to third aspects, the connecting portion (725b) of the first molded body (11b) is annular. The first molded body (11b) includes a plurality of filter parts (723), and the plurality of filter parts (723) are arranged in the circumferential direction of the connection part (725b) outside the connection part (725b). In the second step, the three-dimensionally shaped body (13b) is formed by bending the first molded body (11b) at each boundary between the plurality of filter parts (723) and the connecting part (725b). In the third step, the bottomed tube including the plurality of filter parts (723) as a part of the side wall (141) by integrally molding the second molded body (12) into the three-dimensionally shaped body (13b) by resin molding. Form (14).

  In the filter manufacturing method according to the fifth aspect, the bottomed cylindrical filter (72) can be easily formed while improving the filter performance.

  In the filter manufacturing method according to the sixth aspect, in any one of the first to third aspects, the first molded body (11c) includes a plurality of filter portions (723c). In the first molded body (11c), a plurality of filter parts (723c) are arranged in one direction, and two filter parts (723c) are arranged between two filter parts (723c) adjacent in this one direction. A common connecting part (725c) is interposed. In the second step, the three-dimensionally shaped body (13c) is formed by bending the first molded body (11c) at each boundary between the plurality of filter parts (723c) and the connecting part (725c). In the third step, the bottomed tube including the plurality of filter parts (723c) as a part of the side wall (141) by integrally molding the second molded body (12) into the three-dimensional body (13c) by resin molding. Form (14).

  In the filter manufacturing method according to the sixth aspect, it is possible to easily form the bottomed cylindrical filter (72) while improving the filter performance.

  The filter manufacturing method according to the seventh aspect is any one of the first to sixth aspects, wherein each of the plurality of linear portions (7232) includes two corresponding ones of the plurality of openings (7231). It is elongated in a defined direction along the direction of penetration of the opening (7231). Both ends in the prescribed direction of each of the plurality of linear portions (7232) are tapered.

  In the filter manufacturing method according to the seventh aspect, it is possible to suppress the generation of vortices in the gas flow passing through each of the plurality of openings (7231).

  The smoke detector (1) according to the eighth aspect includes a filter (72) that prevents foreign matter from entering the smoke detection space (Sp1) from the external space. The filter (72) includes a three-dimensionally shaped body (13) and a second molded body (12). The three-dimensionally shaped body (13; 13c) includes a first part including a plurality of filter parts (723) arranged in the circumferential direction and a disk-like connection part (725) connected to the plurality of filter parts (723). In the molded body (11; 11a), the plurality of filter parts (723) are bent at the boundary with the connecting part (725). Each of the plurality of filter parts (723) has a plurality of openings (7231). The 2nd molded object (12) is integrally shape | molded by the solid-shaped object (13). The filter (72) includes a cylindrical body (14) that includes a three-dimensionally shaped body (13) and a second molded body (12) and includes a plurality of filter portions (723) as part of the side wall (141). .

  In the smoke detector (1) according to the eighth aspect, it is possible to improve the filter performance.

DESCRIPTION OF SYMBOLS 1 Smoke detector 11, 11a, 11b, 11c 1st molded object 12 2nd molded object 13, 13c Three-dimensional shaped body 14 Cylindrical body 141 Side wall 72 Filter 723, 723c Filter part 7231 Opening part 7232 Linear part 725, 725b, 725c Connecting part L1 Length Sp1 Smoke sensing space

Claims (8)

1st shaping | molding containing the filter part which has a some opening part and the some linear part located between two adjacent opening parts among these opening parts, and the connection part to which the said filter part is connected A first step of injection molding the body;
A second step of forming the three-dimensionally shaped body by bending the first molded body at the boundary between the filter part and the connecting part;
A third step of forming a cylindrical body including the filter portion as a part of a side wall by integrally molding the second molded body into the three-dimensional shape body by resin molding,
A method for manufacturing a filter. Each of the plurality of linear portions has a length in the shortest axial direction in a cross section perpendicular to the length direction of 0.1 mm or less.
The manufacturing method of the filter of Claim 1. The thickness of at least a part of the second molded body is thicker than the thickness of the first molded body,
The manufacturing method of the filter of Claim 1 or 2. The connecting portion of the first molded body is disk-shaped;
The first molded body includes a plurality of the filter parts, and the plurality of filter parts are arranged in a circumferential direction of the connection part,
In the second step, the solid body is formed by bending the first molded body at each boundary between the plurality of filter parts and the connecting part,
In the third step, a cylindrical body including the plurality of filter portions as a part of a side wall is formed by integrally molding the second molded body into the solid body by resin molding.
The manufacturing method of the filter as described in any one of Claims 1-3. The connecting portion of the first molded body is annular;
The first molded body includes a plurality of the filter parts, and the plurality of filter parts are arranged in the circumferential direction of the connection part outside the connection part,
In the second step, the solid body is formed by bending the first molded body at each boundary between the plurality of filter parts and the connecting part,
In the third step, a bottomed tubular body including the plurality of filter portions as a part of a side wall is formed by integrally molding the second molded body into the solid body by resin molding.
The manufacturing method of the filter as described in any one of Claims 1-3. The first molded body includes a plurality of the filter parts,
In the first molded body, the plurality of filter parts are arranged in one direction, and the connecting part common to the two filter parts is interposed between two filter parts adjacent in the one direction. And
In the second step, the solid body is formed by bending the first molded body at each boundary between the plurality of filter parts and the connecting part,
In the third step, a bottomed tubular body including the plurality of filter portions as a part of a side wall is formed by integrally molding the second molded body into the solid body by resin molding.
The manufacturing method of the filter as described in any one of Claims 1-3. Each of the plurality of linear portions is elongated in a prescribed direction along the penetrating direction of the corresponding two openings of the plurality of openings,
Both ends of the prescribed direction in each of the plurality of linear portions are tapered,
The manufacturing method of the filter as described in any one of Claims 1-6. With a filter that prevents foreign objects from entering the smoke sensing space from the outside space,
The filter is
In the first molded body including a plurality of filter portions each having a plurality of openings and arranged in a circumferential direction and a disk-shaped connecting portion connected to the plurality of filter portions, the plurality of filter portions are A three-dimensional body bent at the boundary with the connecting portion;
A second molded body formed integrally with the three-dimensional shape body,
The filter includes a cylindrical body that includes the three-dimensionally shaped body and the second molded body and includes the plurality of filter portions as a part of a side wall.
smoke detector.

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