JP7655709B2 - Heat detector - Google Patents

Description

The present invention relates to a heat detector equipped with a light source.

Conventionally, heat detectors are equipped with a sensor such as a thermistor that detects heat, and detect the occurrence of a fire by detecting the heat of the hot air currents generated by the fire. In a heat detector, a board is placed inside a case (the detector body), and a sensor is attached to the board so that the heat-sensing part is exposed through an air current inlet provided in the center of the underside of the detector body. Some such heat detectors are equipped with an indicator light such as an LED (Light Emitting Diode) connected to the board, and the indicator light is turned on when a fire occurs (see, for example, Patent Document 1). In the heat detector of Patent Document 1, one indicator light is connected to the board, and is incorporated in an indicator window member provided on the outer periphery of the underside of the detector body.

Japanese Patent Application Publication No. 2-357399

However, the heat detector in Patent Document 1 uses only one indicator light, and the indicator light is provided on the outer periphery of the underside of the detector body, which means that when installing the detector, it is necessary to adjust the orientation of the heat detector so that the indicator light is visible from the entrance to the monitored space.

The present invention was made to solve the above problems, and aims to provide a heat detector that makes installation easier by allowing the indicator light that lights up when the detector is activated to be visible from any direction.

The heat detector of the present invention comprises a case body having an opening on its underside and housing a substrate on which a heat-sensing sensor and a light source are mounted, and a case lid placed in the opening of the case body, the case lid having a central portion and a first hole portion located in the central portion through which the sensor is inserted, the central portion being made of a light-transmitting material, the central portion and the substrate being spaced apart, and light from the light source being emitted to the outside through the central portion.

In addition, the heat detector of the present invention comprises a case body having an opening on its underside, which houses a substrate on which a heat-sensing sensor and a light source are mounted, and a case lid arranged in the opening of the case body, wherein the case lid has a central portion and a first hole portion arranged in the central portion through which the sensor is inserted, the central portion being made of a translucent material, the first hole portion having a mortar shape whose opening width gradually increases from the side facing the light source in the central portion toward the downward side, and is arranged so that the first hole portion overlaps with at least a portion of the light source when projected upward, and light from the light source is emitted to the outside through the central portion.

In addition, the heat detector of the present invention comprises a case body having an opening on its underside and housing a board on which a heat-sensing sensor and a light source are mounted, and a case lid arranged in the opening of the case body, the case lid having a central portion and a first hole portion arranged in the central portion through which the sensor is inserted, the central portion being made of a light-transmitting material, light from the light source being emitted to the outside through the central portion, the board being housed in the height direction of the case body and being arranged within the case body so that the sensor is located at the center of the case body when viewed from below.

According to the present invention, the light from the light source is emitted to the outside through the center, which makes it possible to see the light from the light source regardless of the direction, compared to conventional cases where the light is emitted from a single point on the outer periphery of the underside, and there is no need to adjust the orientation of the heat detector, making installation easier.

1 is a perspective view showing an external appearance of a heat detector according to a first embodiment; FIG. 2 is an exploded perspective view showing the configuration of the heat detector of FIG. 1 . FIG. 2 is a side view showing the heat detector of FIG. 1 installed on a ceiling. FIG. 2 is a bottom view of the heat detector of FIG. 1 . 5 is a cross-sectional view showing the AA section of FIG. 4. 5 is a cross-sectional view showing the cross section BB of FIG. 4. 6 is a cross-sectional view showing the cross section DD of FIG. 5. 5 is a cross-sectional view showing the CC cross section of FIG. 4. 6 is an explanatory diagram showing a state in which a light source in the heat detector of FIG. 5 emits light; FIG. FIG. 11 is a perspective view showing the appearance of a heat detector according to a second embodiment.

Embodiment 1.
1 is a perspective view showing the appearance of a heat detector according to embodiment 1. The heat detector 100 is installed in a monitored space in a building, for example, and monitors the surrounding temperature. When the surrounding temperature reaches or exceeds a certain temperature, the heat detector 100 outputs a signal indicating a fire to a fire receiver (not shown).

Figure 2 is an exploded perspective view showing the configuration of the heat detector of Figure 1. As shown in Figure 2, the heat detector 100 includes a case body 10 having an opening 11, a substrate 20, a sensor 40 that detects heat, a light source 50 that emits light, a case lid 30 that is placed in the opening 11 of the case body 10, and a protector 60 that protects the sensor 40.

2, the substrate 20 is housed in the case body 10 through the opening 11. Various electronic components including the sensor 40 and the light source 50 are mounted on the substrate 20. The case lid 30 is detachably attached to the case body 10 in which the substrate 20 is housed. A first hole 31 through which the sensor 40 is inserted is formed in the central portion 30c of the case lid 30. The protector 60 is provided to protect the tip of the sensor 40 that protrudes in the heat detector 100. The protector 60 is formed with a second hole 61 through which airflow passes. The second hole 61 will be described later. The central portion 30c of the case lid 30 is exposed from a third hole 64a provided in the center of the cover portion 64 of the protector 60, which will be described later, and the central portion 30c of the case lid 30 forms the central portion 30c of the heat detector 100, and similarly, the first hole 31 forms the first hole 31 of the heat detector 100.

Figure 3 is a side view showing the heat detector of Figure 1 installed on a ceiling. As shown in Figure 3, the heat detector 100 is installed, for example, on a ceiling 200 in which a recess 202 is formed on the opposite side to the monitored space. Specifically, the case body 10 is housed in the recess 202 of the ceiling 200, and the heat detector 100 is installed on the ceiling 200 so that the protector 60 protrudes from the ceiling surface 201 into the monitored space.

In each figure, the arrow Z direction is described as representing the height direction (up-down direction) of the heat detector 100 when it is installed on the ceiling 200. That is, in the state where the heat detector 100 is installed on the ceiling 200 as shown in FIG. 3, the side closer to the floor is defined as the bottom. When the heat detector 100 is installed on the ceiling 200, the case body 10 constituting the upper outer surface of the heat detector 100 faces the inner surface of the recess 202 of the ceiling 200, and the protector 60 constituting the lower outer surface of the heat detector 100 is exposed to the room. In addition, the arrow X direction in each figure is defined as representing the width direction (left-right direction) of the heat detector 100, and the arrow Y direction is defined as representing the depth direction (front-back direction) of the heat detector 100. As shown in FIG. 2, the opening 11 of the case body 10 is formed on the bottom surface of the case body 10. In the example shown in FIG. 2, the case body 10 has a box shape with an open bottom surface. Additionally, the first hole 31 is formed in the center portion 30c of the case lid 30.

(Configuration of protector 60)
Fig. 4 is a bottom view of the heat detector of Fig. 1. Fig. 5 is a cross-sectional view showing the A-A cross section of Fig. 4. Fig. 6 is a cross-sectional view showing the B-B cross section of Fig. 4. As shown in Figs. 1, 2, 5 to 6, the protector 60 has a top plate 62 facing the central portion 30c, a cover portion 64 provided above the top plate 62, and a plurality of supports 63 supporting the top plate 62. The cover portion 64 is attached to the case body 10, and is disposed below the case body 10 so as to cover the recess 202 of the ceiling 200 when the heat detector 100 is attached to the ceiling 200. The plurality of supports 63 connect the top plate 62 and the cover portion 64.

As shown in Figs. 1, 2, 5-6, a third hole 64a is formed in the center of the cover portion 64, and as shown in Figs. 1, 2 and 4, the cover portion 64 has a disk shape. The sensor 40 protruding from the case body 10 via the first hole 31 of the center portion 30c is inserted into the third hole 64a.

Although not shown, the cover portion 64 of the protector 60 has two springs extending from the surface facing the case body 10 toward the outer periphery. As shown in FIG. 3, when the case body 10 is housed in the recess 202 of the ceiling 200, the two springs provided on the protector 60 press the left and right inner surfaces of the recess 202, preventing the case body 10 from falling out of the recess 202 of the ceiling 200. Note that the mounting configuration of the heat detector 100 to the ceiling 200 is not limited to this configuration. As shown in FIG. 3, the outer diameter Do2 of the cover portion 64 is set to a dimension larger than the width of the case body 10, and the case body 10 and the recess 202 are configured to be invisible to the user.

1, 2, 4-6, a top plate opening 61a is formed in the center of the top plate 62, and as shown in Figs. 1, 2 and 4, the top plate 62 has a disk shape. As shown in Figs. 3 and 4, in the protector 60, the outer diameter Do1 of the top plate 62 is smaller than the outer diameter Do2 of the cover part 64. The outer diameter Do1 of the top plate 62 and the outer diameter Do2 of the cover part 64 may be the same diameter, or the outer diameter Do1 of the top plate 62 may be larger than the outer diameter Do2 of the cover part 64. The outer diameter, inner diameter, or difference between the outer diameter and the inner diameter of the top plate 62 is determined so that the central part 30c is visible through the second hole part 61 (see Fig. 2) of the protector 60 when the user looks at the heat detector 100 at a predetermined elevation angle. Here, the predetermined elevation angle is the angle at which a user looks up at the heat detector 100; for example, the heat detector 100 installed at a height of 3 meters from the floor may be the angle at which a user located 15 meters away from the heat detector 100 looks up. As shown in FIG. 5, the inner diameter Di1 of the top plate 62, i.e., the opening width of the top plate opening 61a, is preferably set to a dimension (e.g., 8 mm or less) that prevents a test finger or the like from entering.

As shown in Figure 4, when viewed from below of the heat detector 100, the center of the top plate opening 61a of the top plate 62 coincides with the center of the third hole 64a (see Figure 1) of the cover portion 64. Also, as shown in Figure 5, the center of the top plate opening 61a and the center of the third hole 64a in the protector 60 and the center of the first hole 31 are located on a straight line extending in the vertical direction (arrow Z direction), and the sensor 40 is arranged along this straight line.

As shown in FIG. 5, the inner diameter Di1 of the top plate 62, i.e., the opening width of the top plate opening 61a, is set to a dimension equal to or smaller than the inner diameter Di2 of the cover portion 64, i.e., the opening width of the third hole portion 64a. The opening widths of the top plate opening 61a and the third hole portion 64a are also set to a dimension larger than the diameter Ds of the tip portion of the sensor 40 to be inserted, and preferably larger than the opening width Di0 of the first hole portion 31 of the case lid 30. With this configuration, as shown in FIG. 4, when viewed from below the heat detector 100, the central portion 30c of the case lid 30 located inside the protector 60 is visible from outside the heat detector 100 through the top plate opening 61a of the protector 60.

1 and 2, the support 63 of the protector 60 is made of, for example, a plate-shaped member, and the multiple support 63 are arranged radially with a gap G between adjacent support 63. The gap G is preferably set to a dimension (for example, 8 mm or less) that can prevent a test finger or the like from entering. The multiple support 63 and the top plate 62 provided below the central portion 30c constitute a protective portion that protects the tip of the sensor 40 from a finger or the like. In the first embodiment, the support 63 is made of an opaque material. As shown in FIGS. 1 and 5, each support 63 extends downward from the periphery of the third hole portion 64a on the lower surface of the cover portion 64 and is connected to the periphery of the top plate opening 61a on the upper surface of the top plate 62. And, as shown in FIG. 3, the outer diameter Do1 of the top plate 62 is set to a dimension larger than the outer diameter Do3 formed by the multiple support 63 arranged radially. This configuration makes the multiple support posts 63 of the heat detector 100 less visible to users, as shown in Figures 1 and 3, improving the design.

5 and 6, the top plate 62, the multiple support columns 63, the cover portion 64, and the central portion 30c of the protector 60 form an airflow circulation space SP in the protector 60. When the heat detector 100 is installed on the ceiling 200, a vertical airflow flows into the circulation space SP through the top plate opening 61a. Here, the vertical airflow refers to an airflow that flows in a direction perpendicular to the ceiling surface 201. In addition, a horizontal airflow flows into the circulation space SP through the gap G formed between the support columns 63, and the airflow in the circulation space SP flows out of the heat detector 100. Here, the horizontal airflow refers to an airflow that flows in a direction parallel to the ceiling surface 201. In other words, the top plate opening 61a provided in the top plate 62 and the gap G between the multiple support columns 63 each function as a second hole portion 61 (see FIG. 2) through which the airflow flows in the protector 60.

(Configuration of case lid 30)
As shown in FIG. 5, the first hole 31 formed in the central portion 30c of the case lid 30 has a size equal to or larger than the diameter Ds of the heat sensing portion of the sensor 40 protruding from the case lid 30 so that the sensor 40 can be inserted when assembling the heat detector 100. The case lid 30 has a frame member 34 and is configured to cover the lower end of the substrate 20 while exposing the heat sensing portion 41 of the sensor 40 to the outside from the first hole 31 of the central portion 30c. Here, the central portion 30c of the case lid 30 is specifically an area of the case lid 30 exposed to the flow space SP. In the example shown in FIG. 2, the frame member 34 has a rectangular shape, and the central portion 30c is formed in the center of the frame member 34. Note that the frame member 34 and the central portion 30c may be formed of separate members in the case lid 30. The frame member 34 is not limited to a rectangular shape.

The case lid 30 covers the lower end of the substrate 20 while exposing the heat-sensing portion 41 to the outside, and the case lid 30 may be composed of only the frame member 34, with the central portion 30c being constructed separately from the case lid 30. In this case, the central portion 30c may be formed integrally with the cover portion 64 of the protector 60.

The case cover 30 is made of a light-transmitting material. As shown in FIG. 5, the first hole 31 has a mortar shape in which the opening width gradually increases from the upper side of the central portion 30c, i.e., the side facing the light source 50, to the lower side, i.e., the outside where the protector 60 is provided. Note that in this embodiment, the first hole 31 has been described as having a mortar shape, but the shape of the first hole 31 is not limited to this. The opening width Di0 of the first hole 31 above the central portion 30c is larger than the thickness Ds of the tip of the sensor 40 inserted into the first hole 31, and is the same diameter as or smaller than the inner diameter Di1 of the top plate 62 of the protector 60.

As shown in FIG. 2, the case lid 30 is also formed with an injection port 32 for injecting a filler into the case body 10 during the manufacture of the heat detector 100. The filler will be described later. The injection port 32 is provided outside the first hole 31 formed in the center of the case lid 30, and in the example shown in FIG. 2, it is provided at each of the four corners of the case lid 30. Note that the injection port 32 can be omitted, and in that case, the filler can be injected through the first hole 31.

(Substrate 20)
As shown in Fig. 2, the board 20 is, for example, a rectangular printed circuit board. In the example shown in Fig. 2, the board 20 is substantially rectangular with long sides extending in the vertical direction (arrow Z direction), and is disposed in the case body 10 so that both sides of the board 20 face forward and backward. Various electronic components are mounted on the board 20 to form a control circuit.

Figure 7 is a cross-sectional view showing the D-D cross section of Figure 5. As shown in Figures 5 and 7, the light source 50 and the sensor 40 are attached by soldering at predetermined positions on the front surface 21 of the substrate 20. A first cutout portion 23 is formed in the center in the left-right direction (arrow X direction) at the bottom end of the substrate 20. In addition, second cutout portions 24 are formed at positions a certain distance K to the left and right from the center in the left-right direction (arrow X direction) at the bottom end of the substrate 20.

The control circuit formed on the substrate 20 receives the output value of the sensor 40 and determines the ambient temperature based on the output value. Then, when the control circuit determines that the ambient temperature is equal to or higher than a certain temperature, it transmits a fire signal to a receiver (not shown) and controls the light source 50 to light up or blink. The control circuit may be configured to transmit a fire signal to the receiver when there is a temperature change of equal to or higher than a set value in a short period of time, or may be configured to transmit temperature information to the receiver and have the receiver determine whether or not there is a fire.

(Sensor 40)
5 and 6, the sensor 40 has a heat-sensing part 41 that detects heat, and detects the heat of the airflow that has flowed into the flow space SP. The heat-sensing part 41 is composed of, for example, a thermistor whose resistance changes depending on the heat transmitted from the airflow, and converts the temperature change into an electrical signal for output.

The sensor 40 is composed of, for example, a heat-sensing part 41, a rod-shaped lead part 42 made of lead wires, a sensor base 44 having two pins attached to the substrate 20, and a connection part 43 connecting the lead part 42 and the sensor base 44. The heat-sensing part 41 is attached to the tip of the lead part 42, and the heat-sensing part 41 and the lead part 42 are integrally coated. The connection part 43 connects the base end of the lead part 42 to the tip ends of the two pins of the sensor base 44, and is coated with resin or the like. The two pins of the sensor base 44 are fixed to the front surface 21 of the substrate 20 by soldering, and the heat-sensing part 41 is electrically connected to the control circuit of the substrate 20.

The heat-sensing part 41 is disposed directly above the center of the top plate opening 61a of the protector 60 in the flow space SP to detect the heat of the vertical airflow. Specifically, the heat-sensing part 41 is disposed at a preset position in the flow space SP by the sensor base 44 and the lead part 42 connected to the sensor base 44. In the example shown in Figures 5 and 6, the sensor 40 is disposed in parallel with the substrate 20 which is disposed in the vertical direction (arrow Z direction) within the case body 10.

As described above, since the sensor 40 is composed of multiple components, the thickness of the sensor 40 is not constant in the vertical direction, and for example, the connection portion 43 is the thickest. Therefore, in this embodiment, as shown in Figures 5 and 6, the connection portion 43 is arranged in the first cutout portion 23 of the substrate 20. With this configuration, even when a sensor 40 with a non-constant thickness is used, the sensor 40 can be arranged so that the lead portion 42 extends in the vertical direction (arrow Z direction) while avoiding the sensor 40 coming into contact with the substrate 20 at any portion other than the sensor base 44.

The sensor 40 may be configured such that the sensor base 44 is fixed to the lower end of the front surface 21 of the substrate 20 so that the heat-sensing part 41 is located on a downward extension of the substrate 20. In this case, the connection part 43 of the sensor 40 can be disposed between the lower end of the substrate 20 and the inner surface of the case lid 30, and the first cutout part 23 can be omitted.

(Light source 50)
8 is a cross-sectional view showing the CC cross section of FIG. 4. The light source 50 is, for example, an LED (Light Emitting Diode) or the like. As shown in FIGS. 5, 7 to 8, the light source 50 is soldered to the front surface 21 of the substrate 20 at the upper portion thereof so that the light emitting surface 51 (see FIG. 8) faces downward. The light source 50 is preferably mounted on the front surface 21 of the substrate 20 at the lower end portion on the central portion 30c side of the case lid 30. By providing the light source 50 in this manner in the vertical direction (arrow Z direction), it is possible to prevent the light emitted from the light source 50 from being blocked by the substrate 20.

2, 5 and 7, two light sources 50 are mounted on the board 20, one light source 50 is disposed to the right of the sensor 40, and the other light source 50 is disposed to the left of the sensor 40. Specifically, as shown in FIG. 5, when the board 20 is viewed from the front, the upper part of the light source 50 is fixed to the front surface 21 of the board 20 at the periphery of the second cutout portion 24 of the board 20 so that at least a part of the light emitting surface 51 does not overlap with the board 20 disposed behind the light source 50. With this configuration, the progression of light radiated from the light emitting surface 51 of the light source 50 toward the rear and downward can be prevented from being blocked by the board 20, and more light can be incident on the center portion 30c compared to the case where the second cutout portion 24 is not provided.

In this embodiment, the central portion 30c of the case lid 30 is described as being made of a light-transmitting material, but the central portion 30c may be made of a non-light-transmitting material and a light-transmitting hole for emitting light may be provided in the central portion 30c. In this case, the first hole portion 31 may be a light-transmitting hole, or a light-transmitting hole may be provided in the central portion 30c in addition to the first hole portion 31.

5, the light source 50 is provided so that the center of the light-emitting surface 51 coincides with the center of the second cutout portion 24 in the left-right direction (arrow X direction). That is, the distance between the center position of the sensor 40 and the center position of each light source 50 is the same as the distance K between the center of the first cutout portion 23 and the center of each second cutout portion 24, and is the same for both light sources 50. It is preferable that the distance (2K) between the two light sources 50 in the left-right direction (arrow X direction) is equal to or less than the inner diameter Di2 of the cover portion 64 of the protector 60, i.e., the opening width of the third hole portion 64a. In this case, the light of each light source 50 can be more easily viewed through the first hole portion 31.

In addition, in this embodiment, since the central portion 30c is made of a translucent material, light can be emitted from the central portion 30c through the flow space SP. In addition, in this embodiment, since the first hole portion 31 is cone-shaped in the central portion 30c made of a translucent material, the light emitted from the light source 50 can be diffused in the central portion 30c.

When the central portion 30c is made of a translucent material, the distance (2K) between the two light sources 50 in the left-right direction (arrow X direction) may be longer than the opening width Di0 of the first hole portion 31 so that the light from the two light sources 50 enters the case lid 30. This allows the light emitted by the light source 50, particularly the light that is strong and travels downward, to be incident on the translucent material of the case lid 30 and diffused, thereby suppressing the directionality of the light.

The distance (2K) between the two light sources 50 in the left-right direction (arrow X direction) may be further increased to a dimension larger than the opening width of the top plate opening 61a (the inner diameter Di1 of the top plate 62). This allows the top plate 62 to cover the locally bright area directly below the light source 50 in the central portion 30c.

In order to allow the light emitted by the light source 50 provided at the lower end of the substrate 20 to be incident on as wide an area of the central portion 30c as possible, it is preferable that there is a certain distance between the lower end of the substrate 20 and the central portion 30c, as shown in FIG. 5.

(Case body 10)
7, the case body 10 (see FIG. 5) has a case outer shell 12 having a box shape with an open bottom, and a substrate holding portion 13 formed on the inner surface of the case outer shell 12 and holding the substrate 20. When the heat detector 100 is installed on the ceiling 200, the outer surface of the case outer shell 12 faces the inner surface of the recess 202 of the ceiling 200 (see FIG. 3).

As shown in FIG. 7, the board holding portion 13 is provided on the inner surface of each of the left and right side walls of the case outer shell 12. The board holding portion 13 provided on the right side wall of the case outer shell 12 is composed of two protrusions 13a arranged in the front-rear direction (arrow Y direction) protruding from the inner surface of the right side wall, and a groove portion 13b formed between the two protrusions 13a. The board holding portion 13 provided on the left side wall of the case outer shell 12 is composed of two protrusions 13a arranged in the front-rear direction (arrow Y direction) protruding from the inner surface of the left side wall, and a groove portion 13b formed between the two protrusions 13a. The width of each groove portion 13b is slightly wider than the thickness of the board 20, and the right and left ends of the board 20 fit into the groove portions 13b of the two board holding portions 13, respectively, so that the board 20 is positioned at a set position within the case body 10.

In addition, as shown in FIG. 2, the two protrusions 13a in each board holding portion 13 each extend in the vertical direction (arrow Z direction) of the heat detector 100, and also function as a guide for the board 20 when the board 20 is inserted into the case body 10 through the opening 11.

As shown in FIG. 7, the center position (represented by point C1) of each groove 13b in the front-rear direction (arrow Y direction) is slightly shifted backward from the center position (represented by virtual line L1) of the case outer casing 12 in the front-rear direction (arrow Y direction). By providing the board holding portion 13 in this manner, the board 20 can be positioned slightly rearward of the center position of the case outer casing 12 represented by virtual line L1 in the case main body 10. Therefore, as shown in FIG. 7, even if the sensor 40 is fixed to the front surface 21 of the board 20, the sensor 40 can be positioned at the center position of the heat detector 100 in the front-rear direction (arrow Y direction). In addition, the light source 50, which is fixed to the front surface 21 of the board 20 like the sensor 40, can also be positioned at approximately the center position of the heat detector 100 in the front-rear direction (arrow Y direction), and can be viewed from the central portion 30c.

Although not shown, the space inside the case body 10 is filled with a filler through the injection port 32 of the case lid 30 during the manufacture of the heat detector 100, and as the filler hardens, the board 20 on which various electronic components are mounted, the case body 10, and the case lid 30 are fixed together. As the filler hardens, the board 20 is waterproofed. A transparent or translucent light-transmitting material such as polyurethane is used as the filler. The filler is preferably provided so that the light source 50 mounted on the board 20 is covered by the filler. This allows the light emitted by the light source 50 to be diffused in the filler, and prevents the light from being concentrated and incident locally on the central portion 30c.

The flow of air currents during a fire will be explained with reference to Figures 3 and 6. When a fire breaks out in the monitored space, a vertical air current is generated from the source of the fire toward the ceiling 200. After the vertical air current reaches the ceiling 200, the direction of the air current becomes parallel to the ceiling 200 and flows along the ceiling 200 as a horizontal air current. If the source of the fire is directly below the heat detector 100, the vertical air current reaches the top plate 62 or cover part 64 of the protector 60. If the source of the fire is not directly below the heat detector 100, all of the vertical air currents rising from the source of the fire reach the ceiling 200, flow as a horizontal air current along the ceiling surface 201, reach the heat detector 100, and flow in through the gap G of the support 63. The hot air current that flows into the circulation space SP from the gap G of the support 63 passes through the circulation space SP and flows out from the gap G between other supports 63.

Of the hot air currents that reach the protector 60 from the source of the fire, those that reach the center of the top plate 62 flow into the circulation space SP from the top plate opening 61a, pass through the circulation space SP, and flow out of the heat detector 100 through the gap G between the other supports 63. Of the hot air currents that reach the protector 60, those that reach the periphery of the top plate opening 61a in the top plate 62 flow along the top plate 62, and some of them flow into the circulation space SP through the top plate opening 61a. The hot air currents that flow into the circulation space SP through the top plate opening 61a pass through the circulation space SP and flow out of the heat detector 100 through the gap G between the supports 63. The remaining hot air currents that flow along the top plate 62 rise from the outer peripheral surface of the top plate 62 to the cover part 64, merge with the hot air currents that flow out of the circulation space SP through the gap G between the supports 63, and flow through the ceiling 200.

Of the hot air currents that reach the protector 60 from the source of the fire, those that reach the cover section 64 travel along the cover section 64, and when they reach the vicinity of the supports 63, they flow into the protector 60 through the gaps G between the supports 63, pass through the circulation space SP, and flow out of the gaps G between other supports 63.

Heat is transferred to the heat-sensing part 41 from the hot air current passing through the center of the circulation space SP. When heat is transferred to the heat-sensing part 41, the control circuit detects a temperature change based on a signal sent to the board 20 via the lead part 42, and a fire signal is sent from the control circuit to a receiver (not shown), and the control circuit drives the light source 50 to emit light.

Figure 9 is an explanatory diagram showing the state in which the light source emits light in the heat detector of Figure 5. In Figure 9, the dashed arrows represent an example of a group of light rays emitted from the light source 50 into the circulation space SP through the central portion 30c. Also in Figure 9, the dashed arrows represent an example of a group of light rays emitted from the central portion 30c into the circulation space SP, which are emitted outside the heat detector 100 through the second hole portion 61 of the protective portion in the protector 60 (see Figure 2).

The light emitted by the light source 50 is emitted into the circulation space SP in the protector 60 through the circular first hole 31 formed in the central portion 30c, and illuminates the portion of the protector 60 facing the circulation space SP. The light emitted into the circulation space SP is then emitted outside the heat detector 100 through the circular top plate opening 61a formed in the center of the top plate 62 of the protector 60 and the gap G between the multiple pillars 63 arranged radially on the side of the protector 60. Therefore, since light is emitted from the center of the heat detector 100, the light emission indicating the operation of the heat detector 100 can be visually recognized no matter which direction the user looks from with the sensor 40 as the center. As described above, when the central portion 30c is made of a translucent material, the heat detector 100 can emit light through the central portion 30c without emitting light through the first hole 31. Furthermore, if the central portion 30c is made of a non-translucent material, the user can visually recognize the light emitted by the light source 50 through a light-transmitting hole provided in the central portion 30c.

In addition, the central portion 30c is made of a translucent material, and the first hole portion 31 is cone-shaped, so that the surface area from which light is emitted at the central portion 30c is increased, and the heat detector 100 is easily visible even when viewed from the side (front, back, left, or right). In this embodiment, the central portion 30c is provided on the case lid 30, and the entire case lid 30 is made of a translucent material, so there is no need to provide a light guide separately from the case lid 30, as in the conventional case. Furthermore, compared to the conventional case where light is guided by an L-shaped light guide, light loss can be reduced and light can be used more efficiently.

In FIG. 9, two white arrows E1 and E2 each represent the user's line of sight with a different angle of elevation. Below, the components that are visible to the user in each case will be explained. Hereinafter, the elevation angle indicated by the white arrow E1 will be referred to as the first elevation angle, and the elevation angle indicated by the white arrow E2 will be referred to as the second elevation angle. The second elevation angle is an elevation angle smaller than the first elevation angle.

When a user looks at the heat detector 100 at a first elevation angle indicated by the white arrow E1, the central portion 30c can be seen through the top plate opening 61a of the protector 60, and the emitted light of the light source 50 can be confirmed. When a user looks at the heat detector 100 at a second elevation angle indicated by the white arrow E2, the central portion 30c can be seen through the gaps G between the multiple supports 63 of the protector 60. In this case, when a user looks up at the heat detector 100 from the left side as shown in FIG. 9, the inner surface of the right side of the first hole portion 31 having a mortar shape in the central portion 30c can be seen from approximately the front, and the light can be confirmed.

As described above, in the first embodiment, the heat detector 100 includes a case body 10 that houses a substrate 20 on which a heat-detecting sensor 40 and a light source 50 are mounted, an opening 11 on the bottom surface, and a cover portion 64. The cover portion 64 is disposed below the case body 10, and a first hole portion 31 through which the sensor 40 is inserted is disposed in the central portion 30c. In the heat detector 100, light from the light source 50 is emitted to the outside through the central portion 30c. This allows the light to be seen from any direction with the sensor 40 at the center, so there is no need to adjust the orientation of the heat detector 100 during installation, making the installation easier.

The embodiment of the present invention is not limited to the above embodiment, and various modifications can be made. For example, the shape of the case outer shell 12 is not limited to the above, and it can be, for example, a cylindrical shape having an upper surface. For example, the case where the entire case lid 30 is made of a translucent material has been described, but only the central portion 30c of the case lid 30 may be made of a translucent material, and the portion of the case lid 30 other than the central portion 30c may be made of a non-translucent material. In addition, the second hole portion 61 is configured by the top plate opening 61a and the gap G, but this is not limited to this, and it may be configured by only the top plate opening 61a or only the gap G. The above-mentioned heat detector 100 can also be installed on the side wall of the room. In this case, the heat detector 100 is installed on the side wall so that the light emission side of the central portion 30c, i.e., the protector 60 side, is exposed to the room. Even in this case, there is no need to adjust the orientation of the heat detector 100 when installing, and the installation process can be simplified.

Embodiment 2.
10 is a perspective view showing the external appearance of a heat detector according to embodiment 2. Heat detector 100 of embodiment 2 differs from embodiment 1 in that two lid protrusions 33 are provided on case lid 30, and a portion of a plurality of supports 63 is configured by lid protrusions 33. Heat detector 100 of embodiment 2 also differs from embodiment 1 in that band-shaped springs 70 extending outward are provided on the left and right walls of case body 10. Note that the shape of the springs is not particularly limited to this.

When the case body 10 is housed in the recess 202 of the ceiling 200 (see FIG. 3), the two springs 70 provided on the case body 10 press against the left and right inner surfaces of the recess 202 in the ceiling 200, preventing the case body 10 from falling out of the recess 202 in the ceiling 200.

The two lid protrusions 33 are provided on the right and left sides of the cone-shaped first hole 31, protruding toward the protector 60. More specifically, the two lid protrusions 33 are provided along the center line of the case lid 30 in the front-to-rear direction (arrow Y direction) so as to be located directly below the two light sources 50 fixed to the substrate 20. The case lid 30, including the two lid protrusions 33, is made of a translucent material.

In addition, the cover portion 64 of the protector 60 has two first through holes 64b on the right and left sides of the third hole portion 64a. In addition, the top plate 62 of the protector 60 has two second through holes 62b at positions facing the two first through holes 64b of the cover portion 64. The two lid protrusions 33 extending downward from the case lid 30 are inserted into the first through holes 64b of the cover portion 64 of the protector 60, and are exposed from the protector 60 through the second through holes 62b of the top plate 62. In other words, in the heat detector 100 of the second embodiment, the support of the protector 60 is composed of the opaque support 63 and two lid protrusions 33 made of a translucent member.

This allows the light from the light source 50 to be guided straight down through the I-shaped lid protrusion 33 on the case lid 30 and emitted from the protector 60, making it possible to use the light from the light source 50 more efficiently than when an L-shaped light guide is used as in the past.

When removing the heat detector 100 from the installation wall, the worker may hold the top plate 62 and the support pillars 63 of the protector 60. For this reason, it is preferable to have a certain number of support pillars or more to ensure the strength of the protector 60. On the other hand, in order to improve the visibility of the heat detector 100 when the light source 50 is emitting light, it is preferable to have the size of the gap G between the support pillars or more. In the heat detector 100 of embodiment 2, part of the support pillars is configured with two lid protrusions 33 made of a translucent material, so that the number of support pillars is set to a certain number or more to ensure strength, while making it easier to see inside the protector 60 and improving visibility.

1 Case body, 11 Opening, 12 Case outer shell, 13 Board holding portion, 13a Protrusion, 13b Groove, 20 Board, 21 Front, 23 First notch, 24 Second notch, 30 Case lid, 30c Center, 31 First hole, 32 Inlet, 33 Lid protrusion, 34 Frame member, 40 Sensor, 41 Heat sensing portion, 42 Lead portion, 43 Connection portion, 44 Sensor base, 50 Light source, 51 Light emitting surface, 60 Protector, 61 Second hole, 61a Top plate opening, 62 Top plate, 62b Second through hole, 63 Support, 64 Cover portion, 64a Third hole, 64b First through hole, 70 Spring, 100 Heat detector, 200 Ceiling, 201 Ceiling surface, 202 Recess, Di0 Opening width, Di1 inner diameter, Di2 inner diameter, Do1 outer diameter, Do2 outer diameter, Do3 outer diameter, Ds diameter, G gap, K distance, L1 virtual line, SP flow space.

Claims (3)

a case body that houses a substrate on which a heat sensor and a light source are mounted and has an opening on a lower surface;
a case lid disposed at the opening of the case body,
the case lid has a central portion and a first hole portion disposed in the central portion and through which the sensor is inserted,
The central portion is made of a light-transmitting material,
The central portion and the substrate are spaced apart from each other,
The light from the light source is emitted to the outside through the central portion. a case body that houses a substrate on which a heat sensor and a light source are mounted and has an opening on a lower surface;
a case lid disposed at the opening of the case body,
the case lid has a central portion and a first hole portion disposed in the central portion and through which the sensor is inserted,
The central portion is made of a light-transmitting material,
the first hole portion has a mortar shape in which an opening width gradually increases from a side facing the light source in the central portion toward a lower side, and is disposed so as to overlap at least a portion of the light source when the first hole portion is projected upward;
The light from the light source is emitted to the outside through the central portion. a case body that houses a substrate on which a heat sensor and a light source are mounted and has an opening on a lower surface;
a case lid disposed at the opening of the case body,
the case lid has a central portion and a first hole portion disposed in the central portion and through which the sensor is inserted,
The central portion is made of a light-transmitting material,
The light from the light source is emitted to the outside through the central portion,
The substrate is stored in the height direction of the case body, and is disposed within the case body such that the sensor is located at the center of the case body when viewed from below.

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