Fire detector

Abstract

To provide an embedded type fire sensor capable of preventing breakage of a ceiling, a wall and the like.SOLUTION: In a fire sensor 1, a flange part 3 is attached in pressure contact with a part on a side of an attachment hole H, which is located on an attachment object T such as a ceiling and a wall, by elastic force of attachment springs 7 in a state where a main body 2 is embedded in the attachment hole H. The attachment spring 7 is a wire spring, where an outer side part 7aa coming into contact with the part of the attachment hole H when detaching the fire sensor 1 has a smooth shape.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a fire detector. [Background technology]

[0002] Fire detectors are installed to detect fires that occur inside buildings that are being protected. They are broadly divided into heat detectors and smoke detectors. Both are mainly installed on the ceilings or walls of buildings.

[0003] In the case of a built-in fire detector, it is mounted in a state where it is embedded in a mounting hole provided in the mounting object such as a ceiling or a wall. The mounting structure employs a mounting configuration in which the flange is pressed against the periphery of the opening on the front side of the mounting hole by the elastic force of a mounting spring (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2000-20845 Summary of the Invention [Problem to be solved by the invention]

[0005] Conventionally, a mounting spring in an embedded fire detector is a leaf spring having a hook-shaped catch portion at the tip end, such as the mounting spring disclosed in Patent Document 1.

[0006] However, when removing a fire detector that has already been installed, the tip of the hook-shaped catch may come into sharp contact with the inner surface of the mounting hole or other part of the mounting hole, scraping that part and damaging the ceiling, wall, etc. The possibility of damage is particularly high when the ceiling, wall, etc. is made of a board that is easily scraped, such as gypsum board.

[0007] SUMMARY OF THE INVENTION In view of the above circumstances, an object of the present invention is to provide a built-in fire detector that can prevent damage to ceilings, walls, etc. [Means for solving the problem]

[0008] In this invention, the main body is embedded in a mounting hole provided in a mounting object such as a ceiling or a wall, and the flange Back of is caused by the elastic force of the mounting spring. That Mounting holes Around the front opening It is attached by pressing it into the part. Filled In a built-in fire detector, the mounting spring is elastically extended toward the rear side of the flange. Apply force The flange portion contacts the edge of the rear opening of the mounting hole. Back of the periphery of the front opening of the mounting hole minutes It is a wire spring having an arm portion that is pressed against the ,before Arm section teeth , made from wire rod with a circular cross section The outer part has a smooth outer surface, and the tip part has a shape in which there is no cut part of the wire, or there is a cut part of the wire but it has a shape that is bent in the opposite direction to the direction in which the elastic force acts, and when the fire detector is removed, the outer part and the tip part come into contact with the inner surface part of the mounting hole but do not come into contact with sharp edges. A fire detector characterized by the above.

[0009] In the present invention, the smooth shape of the wire spring can be a completely smooth shape or a substantially smooth shape. The wire spring has an arm portion extending from a coil portion that resiliently moves toward the rear side of the flange portion. Apply force The torsion coil spring may be a torsion coil spring arranged such that the arm portion contacts the edge of the rear opening of the mounting hole, and presses the flange against the periphery of the front opening of the mounting hole. The torsion coil spring may be a double torsion spring having two coil portions, and the arm portion may extend from the coil portion in an inverted U shape. The coil portion may be in contact with the rear side of the flange or may be arranged in a position close to it. The arm portion may be elastically extended to a position where it contacts the rear side of the flange or may be close to it. Apply force The arm portion may be provided with a resilient tip end. Force acts The bent portion may have an obtuse angle that is inclined toward the side where the bent portion is to be bent. [Effects of the Invention]

[0010] In this invention, a wire spring is used as the mounting spring, and the portion that comes into contact with the mounting hole when the fire detector is removed has a smooth shape. Therefore, even if the mounting spring comes into contact with the inner surface of the mounting hole or other portion of the mounting hole when the fire detector is removed after being installed, scraping that portion can be prevented.

[0011] Therefore, according to the present invention, it is possible to obtain a built-in fire detector that can prevent damage to ceilings, walls, etc. [Brief explanation of the drawings]

[0012] [Figure 1] This shows a heat detector, which is an example of an embodiment of a fire detector of this invention, and is a side view of the entire detector viewed from the longitudinal side of the mounting spring (in contact with the back side of the flange plate). [Figure 2] FIG. 2 is a view of FIG. 1 as seen from the right. [Figure 3] This is a view of FIG. 1 as seen from below, showing the front side of the detector. [Figure 4] 2 is a view of FIG. 1 as seen from above, showing the rear side of the sensor. [Figure 5] This is a cross-sectional view of the heat detector when it is attached to a thick mounting hole on a ceiling, wall, or other surface where the mounting hole is deep (the mounting spring is in contact with the edge of the rear opening of the mounting hole). [Figure 6] 6 is a diagram corresponding to FIG. 5, illustrating the case where the heat detector is attached to a thin plate material of a ceiling, wall, or the like and the mounting hole has a shallow depth. DETAILED DESCRIPTION OF THE INVENTION

[0013] An example of an embodiment of the present invention will be described below, taking as an example a case where the present invention is applied to a heat detector, with reference to Figures 1 to 6. Note that the present invention can also be applied to a built-in smoke detector.

[0014] In this invention, the terms "front" and "back" that indicate orientation or position, such as "front" and "back", are used according to the orientation or position of each component part relative to the space inside the building, etc. that is the monitoring target, when the heat detector is installed. For example, if the heat detector is installed on the ceiling, the side facing the space below the monitoring target is used as the "front", and the opposite side is used as the "back".

[0015] [Basic configuration] As shown in Figures 1 to 6, heat detector 1 is used as a fire detector and includes housing 2 (an example of a main body), flange plate 3 (an example of a flange portion) provided on the front side of housing 2, and protector 4 provided on the front side of flange plate 3. Housing 2 houses circuit board 5 on which various electrical components are mounted, and circuit board 5 is connected and fixed to thermistor 6, which functions as heat-sensing means, with thermistor 6 standing upright facing forward and its tip end portion, where heat-sensing portion 6a is provided, exposed in front of flange plate 3 (see Figures 5 and 6). Protector 4 protects the tip end portion of thermistor 6 from external forces while ensuring the inflow of hot air from the outside to heat-sensing portion 6a of thermistor 6. Protector 4 includes top plate 4a that protects the tip end portion from the front and multiple support columns 4b that protect it from the sides.

[0016] [Mounting spring] The heat detector 1 is an embedded type in which the housing 2 is mounted in a state where it is embedded in a mounting hole H provided in the mounting object T such as a ceiling or a wall (see Figures 5 and 6). As a mounting member for the mounting hole H, the heat detector 1 is provided with a mounting spring 7 that presses the back surface 3a of the flange plate 3 against the peripheral portion FP of the front opening FO of the mounting hole H to maintain the mounting state in the mounting hole H.

[0017] In the heat detector 1, a wire spring is used as the mounting spring 7, and the portion that comes into contact with the portion on the mounting hole H side, such as the inner surface portion IP of the mounting hole H, when the housing 2 is removed from the mounting hole H (for example, the outer portion 7aa of the arm portion 7a, which will be described later) has a smooth shape. Therefore, even if the mounting spring 7 comes into contact with the portion on the mounting hole H side when the heat detector 1 is removed after being installed, it is possible to prevent the portion from being scraped off. In other words, it is possible to prevent damage to the mounting target T, such as a ceiling or wall.

[0018] [Example of mounting spring] Torsion coil springs A torsion coil spring is preferably used as the wire spring for the mounting spring 7. Although a torsion coil spring with one coil may be used, a type with two coils, known as a double torsion spring, is preferably used. By using a spring with two coils, it is possible to increase the rotational torque of the deforming part (for example, the arm portion 7a described below) during elastic deformation.

[0019] ·Structure, arrangement In the illustrated example, the mounting spring 7 is a torsion coil spring with two coils, with two coaxially aligned coil portions 7b and an inverted U-shaped arm portion 7a extending from the two coil portions 7b and connecting them. The arm portion 7a has a length such that, when the heat detector 1 is attached to the mounting hole H, the position of its tip portion 7ab exceeds the edge BE of the rear opening BO of the mounting hole H (see FIG. 5). For example, the arm portion 7a has a length approximately twice the height of the housing 2, allowing the heat detector 1 to be attached even in cases where the ceiling is thick. Two arm portions 7a are provided on both sides of the housing 2, forming a pair. Each arm portion 7a has two coaxially aligned coil portions 7b in a direction perpendicular to the longitudinal direction of the housing 2, and the arm portion 7a, which rotates around the central axis of the two coil portions 7b, elastically deforms toward the rear surface 3a of the flange plate 3. The elastic force is applied by The arrangement is as follows:

[0020] Installation state As shown in FIGS. 5 and 6, when the heat detector 1 is attached to the attachment hole H, the attachment spring 7 has the elasticity of the arm portion 7a. the action of force The portion of outer portion 7aa facing in the direction of rotation comes into contact with edge BE of rear opening BO of mounting hole H. As a result, the elastic force of arm portion 7a in the rotation direction acts as a force in the direction of pulling up the entire detector, and as described above, rear surface 3a of flange plate 3 is pressed against peripheral portion FP of front opening FO of mounting hole H, and heat detector 1 is maintained in a state attached to mounting hole H.

[0021] State when removed When the attached heat detector 1 is removed from the attachment hole H, the attachment spring 7 is configured such that the elasticity of the arm portion 7a is increased by pulling the heat detector 1 downward. the action of force The outer portion 7aa on the side facing the direction is pulled out from the mounting hole H while contacting the mounting hole H side portions such as the edge BE of the rear opening BO, the inner surface portion IP, and the edge FE of the front opening FO.

[0022] Smooth shape The arm portion 7a is formed so that its outer portion 7aa, which faces and comes into contact with the portion on the mounting hole H side, has a smooth shape. The arm portion 7a is formed, for example, from a wire rod with a circular cross section as part of a wire spring, and the outer portion 7aa is formed so that it has a smooth outer surface. This also makes it possible to prevent damage to the portion on the mounting hole H side when removing the heat detector 1 from the mounting hole H.

[0023] The smooth shape of the outer portion 7aa may be a completely smooth, straight shape with no curved portions when viewed from the side (the shape when viewed from the side in the longitudinal direction; the same applies below), or may be a substantially smooth, continuous, straight shape including curved portions, as long as the deflection angle α of the direction of the tip end 7ab relative to the direction of the base end 7ad is not 90 degrees or more (see Figure 1) and the portion on the tip end 7ab side is not curved so much as to form a hook-like catch on the portion on the mounting hole H side.

[0024] In the illustrated example, the arm portion 7a has an obtuse-angle bent portion 7ac, which will be described later, provided midway in the length direction, and has a shape in which a straight portion on the base end portion 7ad side and a straight portion on the tip end portion 7ab side are continuous via the bent portion 7ac. In the shape seen from the side, the portion on the tip end portion 7ab side is bent so as to be inclined toward the side where it is elastically deformed by the obtuse-angle bent portion 7ac, but the deflection angle α of the direction of the tip end portion 7ab with respect to the direction of the base end portion 7ad is not 90 degrees or more (see FIG. 1), and the arm portion 7a is not bent to the extent that it forms a hook-like catch on the portion on the mounting hole H side. In other words, in the shape seen from the side, the portion on the tip end portion 7ab side is bent so as to be inclined toward the side where it is elastically deformed by the obtuse-angle bent portion 7ac. Direction of force action Although the outer portion 7aa is bent to the side, it is not bent to the extent that it forms a hook-like catch on the portion on the mounting hole H side, and has a continuous, straight, and generally smooth shape, so that the outer portion 7aa that comes into contact with the portion on the mounting hole H side has such a continuous, straight, and generally smooth shape in side view.

[0025] Tip shape As described above, arm portion 7a is configured to have an inverted U-shape. That is, arm portion 7a is folded back at tip portion 7ab and continues, and there is no cut portion of the wire at tip portion 7ab (see FIG. 2). In the illustrated example, when heat detector 1 is removed from mounting hole H, tip portion 7ab will also come into contact with the portion on the mounting hole H side. However, by not having a cut portion of the wire, tip portion 7ab can be prevented from coming into sharp contact with the portion on the mounting hole H side. That is, by configuring arm portion 7a to have an inverted U-shape, it is possible to prevent the portion on the mounting hole H side from being scraped when heat detector 1 is removed from mounting hole H.

[0026] When a torsion coil spring with one coil is used as the mounting spring 7, the spring has a cut portion at the tip of the arm. Direction of force actionEven if there is a cut part of the wire, it is possible to prevent that part from being scraped off by bending it in the opposite direction so that it does not come into sharp contact with the part on the mounting hole H side.

[0027] -Support for thickness of plate materials The plate material used for the mounting object T, such as a ceiling or wall, may be thick or thin. Figures 5 and 6 show the mounting state of the heat detector 1 to the mounting object T, with Figure 5 showing the state when the mounting object T has a thick plate material, and Figure 6 showing the state when the mounting object T has a thin plate material. The mounting spring 7 can be used satisfactorily in either case.

[0028] Obtuse angle bends The arm portion 7a has a resilient portion on the tip end portion 7ab side. Direction of force action An obtuse angle bent portion 7ac is provided midway in the length direction, inclining the heat detector 1 to the side. This allows the heat detector 1 to be securely attached to the mounting hole H even when the plate member of the mounting object T is thick.

[0029] Specifically, for example, when the plate member of the mounting object T is thick as shown in Fig. 5, when the heat detector 1 is mounted in the mounting hole H, the outer portion 7aa of the portion on the side of the tip portion 7ab comes into contact with the edge portion BE of the rear opening BO of the mounting hole H. At that time, the portion on the side of the tip portion 7ab is elastic. Direction of force action By bending the arm 7a to the side, the elastic force in the rotational direction of the arm 7a can be made to act more strongly as a force in the direction of lifting the entire sensor. That is, even if the plate member of the mounting object T is thick as shown in Figure 5, the back surface 3a of the flange plate 3 can be sufficiently pressed against the peripheral portion FP of the front opening FO of the mounting hole H, and the mounting state in the mounting hole H can be maintained satisfactorily.

[0030] Even if such a bent portion 7ac is provided, the portion on the tip end 7ab side is not bent so as to form a hook-like catch on the portion on the mounting hole H side, so that when the heat detector 1 is removed from the mounting hole H, damage such as scraping of the portion on the mounting hole H side can be prevented, as described above.

[0031] The angle β of this bent portion 7ac can be set to an appropriate angle within the range of obtuse angles, taking into consideration the dimensions of the portion on the mounting hole H side, such as the diameter of the mounting hole H, so that the deflection angle α of the direction of tip end portion 7ab relative to the direction of base end portion 7ad does not exceed 90 degrees and so that the portion on the tip end portion 7ab side does not bend so much as to form a hook-like catch on the portion on the mounting hole H side. However, from the perspective of preventing damage to the portion on the mounting hole H side, it is preferable to set the angle to a large angle (for example, approximately 120 degrees or more) even within the range of obtuse angles.

[0032] In the illustrated example, the number of bent portions 7ac is one, but there may be more than one as long as the deflection angle α of the direction of the tip end 7ab relative to the direction of the base end 7ad does not exceed 90 degrees overall and the portion on the tip end 7ab side is not bent to the extent that it forms a hook-like catch on the portion on the mounting hole H side.

[0033] Coil position Place The coil portion 7b is provided on the rear surface 3a side of the flange plate 3 in the above-mentioned arrangement, but is provided in a position where it contacts the rear surface 3a side of the flange plate 3 or is close to it, and the arm portion 7a is elastically moved to a position where it contacts the rear surface 3a side of the flange plate 3 or is close to it. Apply force By making it possible to provide such a structure, when the heat detector 1 is attached to the mounting hole H, the attached state to the mounting hole H can be maintained satisfactorily even if the plate member of the attachment object T is thin.

[0034] Specifically, in the illustrated example, the coil portion 7b is provided at a position where it contacts the rear surface 3a of the flange plate 3, and the arm portion 7a is elastically extended to a position where the outer portion 7aa contacts the rear surface 3a of the flange plate 3. Apply forceAs a result, even if the plate material of the attachment target T is thin as shown in Fig. 6, the outer portion 7aa of the portion of the arm portion 7a on the base end 7ad side can be brought into contact with the edge portion BE of the back opening BO of the attachment hole H, and the elastic force of the arm portion 7a in the rotational direction can be made to act as a force in the direction of lifting the entire sensor. In other words, even if the plate material of the attachment target T is thin as shown in Fig. 6, the back surface 3a of the flange plate 3 can be sufficiently pressed against the peripheral portion FP of the front opening FO of the attachment hole H, and the attachment state to the attachment hole H can be maintained satisfactorily.

[0035] In this way, the coil portion 7b is provided at a position where it contacts the rear surface 3a of the flange plate 3, and the arm portion 7a is elastically moved to a position where the outer portion 7aa contacts the rear surface 3a of the flange plate 3. Apply force Even if the outer portion 7aa is provided with a continuous, linear, and generally smooth shape, as described above, the outer portion 7aa still has the same shape. In other words, when removing the heat detector 1 from the mounting hole H, it is possible to prevent the portion on the mounting hole H side from being scraped off, as described above.

[0036] [Configuration change example] The above describes an embodiment of the present invention with reference to the drawings, taking as an example a case where the present invention is applied to a heat detector. However, the specific configuration is not limited to the above embodiment, and includes designs within the scope that do not deviate from the gist of the present invention.

[0037] For example, the arm portion 7a has a portion on the tip end portion 7ab side that is elastic. Direction of force action In the illustrated embodiment, a bent portion 7ac with an obtuse angle that bends the tip end 7ab toward the center is provided midway in the longitudinal direction, but the angle of inclination and the position of the bent portion are not limited to the example shown in the figure. Direction of force actionThe coil portion 7b may be provided so as to be inclined in a direction opposite to the direction of the arrow A. The position of the coil portion 7b has been described as being in contact with or close to the rear surface 3a of the flange plate 3, but this is not limiting and the coil portion 7b may be provided so as to be in contact with the trunk of the housing 2, which is the main body. In the above embodiment, the mounting spring 7 is provided directly on the heat detector 1, but a similar mounting spring may be provided on a mounting means for mounting to a mounting surface such as a detector mounting base. [Explanation of symbols]

[0038] 1: Heat detector (fire detector) 2: Housing (main body) 3: Flange plate (flange part) 3a: Rear 4: Protector 4a: Top panel 4b: Support 5: Circuit board 6: Thermistor 6a: Heat-sensing part 7: Mounting spring 7a: Arm part 7aa: Outside part 7ab: Tip part 7ac: Bent part 7ad: Proximal part 7b: Coil section T: Mounting target H: Mounting hole BO: Rear opening BE: Edge (rear side) FO: Front opening FE: Edge (front side) FP: Periphery (front side) IP:Inner part

Claims

1. A built-in fire detector in which the main body is embedded in a mounting hole provided in a mounting object such as a ceiling or a wall, and the back surface of the flange is pressed against the peripheral portion of the front opening of the mounting hole by the elastic force of a mounting spring, the mounting spring is a wire spring having an arm portion that applies an elastic force toward the rear side of the flange portion, contacts the edge of the rear opening of the mounting hole, and presses the rear side of the flange portion against the peripheral portion of the front opening of the mounting hole, the arm portion is formed from a wire rod having a circular cross section, the outer portion thereof has a smooth outer surface, and the tip portion thereof has a shape in which there is no cut portion of the wire rod, or a shape in which there is a cut portion of the wire rod but which is bent in a direction opposite to the direction in which the elastic force acts, The fire detector is characterized in that the outer portion and the tip portion come into contact with the inner surface of the mounting hole when the fire detector is removed, but do not come into contact with any sharp edges.

2. 2. The fire detector according to claim 1, wherein the tip of the arm portion has a loop shape with no cut portion of the wire.

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