JP7745211B2 - Detectors and automatic fire alarm systems - Google Patents

Description

This disclosure relates generally to detectors and automatic fire alarm systems, and more specifically to detectors that detect heat generated by, for example, a fire, and automatic fire alarm systems equipped with such detectors.

As a conventional example, the combined heat and smoke detector described in Patent Document 1 is exemplified. This detector comprises a heat detection means for detecting heat and a smoke detection unit for detecting smoke that has flowed into the dark box. The heat detection means comprises a lead wire connected to a circuit board and protruding upward from the circuit board, and a heat-sensitive element such as a thermistor attached to the upper end of the lead wire.

JP 2012-014330 A

In the detector of Patent Document 1, the heat-sensitive element is located at the upper end of the lead wire, which may make it difficult to reduce the overall size (particularly the thickness) of the detector, depending on the length of the lead wire.

This disclosure has been made in light of the above reasons, and aims to provide a detector and automatic fire alarm system that can be made smaller.

A detector according to one aspect of the present disclosure includes a substrate, a heat detection element, and a housing. The housing accommodates the substrate. The housing has a flow path provided in its internal space through which gas flows, an opening connecting the flow path to an external space of the housing, and a smoke detection unit disposed in the internal space and configured to detect smoke. The heat detection element is a chip thermistor mounted on the substrate and configured to detect the heat of the gas flowing in through the opening. The smoke detection unit is disposed on a different plane from the surface of the substrate on which the chip thermistor is mounted.
A detector according to one aspect of the present disclosure includes a substrate, a thermal detection element, and a housing. The housing accommodates the substrate. The housing has a flow path provided in its internal space through which gas flows, an opening connecting the flow path to an external space of the housing, and a smoke detection unit disposed in the internal space and detecting smoke. The thermal detection element is a chip thermistor mounted on the substrate and detects the heat of the gas flowing in through the opening. The housing has one or more walls in the internal space that guide the gas to the thermal detection element or the smoke detection unit.
A sensor according to one aspect of the present disclosure includes a substrate, a thermal detection element, and a housing. The housing accommodates the substrate. The housing has a flow path provided in its internal space through which gas flows, an opening connecting the flow path to an external space of the housing, and a smoke detection unit disposed in the internal space and detecting smoke. The thermal detection element is a chip thermistor mounted on the substrate and detecting the heat of the gas flowing in through the opening. The housing has an installation surface facing a structure to which the sensor is attached. The smoke detection unit has an optical element that emits light, a light-receiving element that receives the light emitted from the optical element, and a labyrinth portion in which the optical element and the light-receiving element are arranged so as not to face each other. In the thickness direction of the substrate, the center of the internal space of the labyrinth portion is between the chip thermistor and the installation surface.
A sensor according to one aspect of the present disclosure includes a substrate, a thermal detection element, and a housing. The housing accommodates the substrate. The housing has a flow path provided in its internal space through which gas flows, an opening connecting the flow path to an external space of the housing, and a smoke detector disposed in the internal space for detecting smoke. The thermal detection element is a chip thermistor mounted on the substrate and detects the heat of the gas flowing in through the opening. The housing has an installation surface facing a structure to which the sensor is attached. The substrate has a first surface facing the installation surface and a second surface opposite the first surface. The chip thermistor is mounted on the first surface or the second surface, which is a mounting surface of the substrate. The chip thermistor has a rectangular shape when viewed perpendicularly to the mounting surface of the substrate and has one surface facing the substrate in the thickness direction of the substrate.
An automatic fire alarm system according to one aspect of the present disclosure includes the above-described sensor and a receiver that communicates with the sensor.

This disclosure has the advantage of enabling miniaturization.

FIG. 1 is a cross-sectional view of a sensor according to a first embodiment. FIG. 2 is a perspective view of the sensor as viewed from below. Fig. 3A is a partially see-through plan view of the sensor, and Fig. 3B is an enlarged plan view of a main part of Fig. 3A. FIG. 4 is a schematic block diagram of the sensor. FIG. 5 is an enlarged front view of the opening of the sensor. FIG. 6 is a schematic cross-sectional view of a first modified example of the sensor. FIG. 7 is a schematic cross-sectional view of a second modification of the sensor. 8A and 8B are perspective and partially see-through plan views of the sensor according to the third modification, as viewed from below, and the sensor according to the third modification, respectively; 9A and 9B are perspective and partially see-through plan views of the fourth modification of the sensor, respectively, as viewed from below and as viewed from the bottom. 10A and 10B are perspective and partially see-through plan views of the fifth modified example of the sensor, respectively, as viewed from below and in the same manner as in the first modified example. FIG. 11 is a perspective view of another modified example of the sensor as viewed from below. Fig. 12A is a side view of a main part of a sensor according to embodiment 2. Fig. 12B is a cross-sectional view of the main part of the sensor taken along the horizontal direction. Fig. 13A is a side view of a main part of the sensor according to the first modification, Fig. 13B is a cross-sectional view of the main part of the sensor according to the first modification taken along the horizontal direction, Fig. 13C is a cross-sectional view of the main part of another example of the sensor according to the first modification taken along the horizontal direction. 14A is a side view of a main part of the sensor according to the second modification, FIG. 14B is a cross-sectional view of the main part of the sensor according to the second modification taken along the horizontal direction, and FIG. 14C is a perspective view of the main part of the sensor according to the second modification. FIG. 15 is an exploded perspective view of the main part of the second modified example. FIG. 16 is a side view of a main part of a third modification of the sensor. 17A and 17B are side and horizontal cross-sectional views of the main parts of the sensor according to the fourth modification; Fig. 18A is a perspective view from below of a sensor according to embodiment 3. Fig. 18B is a partially see-through plan view of the sensor. Fig. 18C is a vertical cross-sectional view of a main part of the sensor near an inlet. Fig. 19A is a diagram showing a state in which the above-mentioned sensor installed in a structure is subjected to a heating inspection using a tester, and Fig. 19B is a schematic cross-sectional view of the tester in a state in which the above-mentioned sensor is covered with the tester. FIG. 20 is a perspective view of a modified example of the sensor as viewed from below. Fig. 21A is a perspective view showing a state in which a main body of a sensor according to embodiment 4 is directly attached to a structure using a mounting base, and Fig. 21B is an exploded perspective view of the main body of the sensor and the mounting base. 22A is a perspective view showing the sensor body embedded in a structure using an embedding base, and FIG 22B is an exploded perspective view of the sensor body and the embedding base. 23A and 23B are partial cross-sectional views schematically showing how the embedded base is attached to a structure using a first mounting bracket and a second mounting bracket, respectively.

(Embodiment 1)
(1) Overview The drawings described in the following embodiments are schematic diagrams, and the ratios of the sizes and thicknesses of the components in the drawings do not necessarily reflect the actual dimensional ratios.

The detector 1 of this embodiment is, for example, a fire detector, and is equipped with a heat detection element 30 that detects heat generated by a fire or the like. In other words, the detector 1 is a detector that has at least the function of detecting heat. In the following, as an example, the detector 1 is assumed to be a so-called combined fire detector (see Figures 1 to 5) that also includes a smoke detection unit 4 (see Figure 1). The detector 1 may also be equipped with a detection unit that detects flames, gas leaks, or the generation of CO (carbon monoxide) due to incomplete combustion, instead of or in addition to the smoke detection unit 4.

As shown in Figure 2, the detector 1 is installed on a structure X1 (the ceiling in the illustrated example), which is a construction material such as the ceiling or wall of a building.

As shown in Figures 1 to 3A, the detector 1 includes a substrate 2, one or more thermal detection elements 30, and a housing 5. In this example, the detector 1 includes four thermal detection elements 30.

The housing 5 houses the substrate 2. As shown in FIG. 1, the housing 5 has a flow path 6 provided in its internal space SP1 through which gas flows, and an opening 7 connecting the flow path 6 to the external space SP2 of the housing 5. In FIG. 1, the flow path 6 is shown schematically with an arrow line to make the gas flow easier to understand, but the gap around the smoke detector 4 in the internal space SP1 can roughly correspond to the flow path 6. Also, as an example, the housing 5 has six openings 7 (only three are shown in FIG. 2).

Here, the thermal detection element 30 in this embodiment is a chip thermistor mounted on the substrate 2, as shown in Figure 1, which detects the heat of the gas flowing in through the opening 7.

With this configuration, the thermal detection element 30 is a chip thermistor mounted on the substrate 2, which allows for the overall size (and particularly thickness) of the detector 1 to be made smaller (especially thinner) than, for example, the configuration in Patent Document 1 in which the thermal element is provided at the upper end of the lead wire.

(2) Details (2.1) Overall Configuration The overall configuration of the detector 1 according to this embodiment will be described in detail below. As described above, the detector 1 is a so-called combined fire detector that detects heat and smoke.

In the following, we will assume that detector 1 is installed on the ceiling surface (one surface of structure X1), as in the example of Figure 2. Therefore, the up/down, left/right, and front/rear directions of detector 1 will be defined and explained using the up/down, left/right, and front/rear arrows shown in Figure 2. These arrows are merely provided to aid in the explanation and have no substance. Furthermore, these directions are not intended to limit the direction in which detector 1 can be used.

The detector 1 is equipped with a heat detection unit 3 having the four heat detection elements 30 described above. In addition to the substrate 2, heat detection unit 3, smoke detection unit 4, and housing 5, the detector 1 further comprises a display unit 8 and a control unit 9 (see Figure 4). The detector 1 also comprises a mounting unit 10 for mounting to the structure X1 (see Figure 1). Figure 1 does not show the mounting structure (e.g., a disk-shaped mounting base) on the structure X1 side to which the mounting unit 10 is fixed. The detector 1 is detachably mounted to the mounting base fixed to the structure X1.

When a fire is detected, the detector 1 transmits a signal to an external alarm device (not shown) to notify the occurrence of a fire, and is equipped with a communication unit 11 that receives signals from the alarm device.

The detector 1 may be powered by a commercial power source or by a battery installed inside the housing 5.

(2.2) Housing The housing 5 accommodates the circuit board 2, the heat detection unit 3, the smoke detection unit 4, the light source 81 of the display unit 8, the control unit 9, the communication unit 11, and other circuit modules. The housing 5 also supports the guide unit 82 of the display unit 8 so that one surface of the guide unit 82 is exposed to the outside (see FIG. 2).

The housing 5 is made of synthetic resin, such as flame-retardant ABS resin. The housing 5 is formed as a whole in the shape of a cylinder that is flat in the vertical direction. As shown in FIG. 1, the housing 5 has a cylindrical front cover 51 with one open surface (the top surface in the illustrated example), and a disk-shaped back cover 52. The housing 5 has an installation surface 55 (see FIG. 1) that faces the structure X1 to which the sensor 1 is attached. In this case, one surface (top surface) of the back cover 52 corresponds to the installation surface 55. The housing 5 is constructed by assembling the back cover 52 to the front cover 51 from the open surface side.

As described above, the housing 5 has a flow path 6 provided in its internal space SP1 through which gas flows, and six side openings (horizontal holes) 7A as six openings 7 connecting the flow path 6 with the external space SP2. In other words, the openings 7 have side openings 7A. There is no particular limit to the number of openings 7, but considering the flow of gas in and out of the housing 5, it is preferable to have two or more.

Here, six openings 7 (six side openings 7A) are provided in the front cover 51. Specifically, as shown in Figures 1 and 2, the front cover 51 is composed of a flat cylinder 510 with both upper and lower ends open, a disk-shaped base 511 below the cylinder 510, and multiple (e.g., six) crosspieces 512 connecting the cylinder 510 and base 511. The cylinder 510, base 511, and six crosspieces 512 are integrally formed. The six crosspieces 512 are arranged at approximately equal intervals along the circumferential direction on the peripheral edge of the base 511 and protrude from the peripheral edge toward the open lower edge of the cylinder 510. The six crosspieces 512 maintain a specified distance between the cylinder 510 and the base 511. The six openings 7 are arranged at approximately equal intervals along the circumferential direction on the peripheral wall of the front cover 51 configured in this manner.

Each opening 7 (each side opening 7A) is a roughly rectangular through-hole that penetrates radially through the peripheral wall of the front cover 51, and serves as an opening connecting the flow path 6 to the external space SP2.

The front cover 51 has a positioning structure on the upper surface of the base 511 for positioning the board 2. One example of the positioning structure is a positioning recess on the upper surface of the base 511, into which a tab protruding from the board 2 can fit. As shown in Figure 3A, the base 511 has a diameter slightly larger than the diameter of the board 2.

The front cover 51 also has a pair of holes 513 (see Figure 3A) in the base 511 for exposing one surface (bottom surface) of the guide portion 82 of the display unit 8 to the external space SP2.

When the base 511 is viewed from below, the pair of holes 513 are located near the peripheral edge of the base 511. The pair of holes 513 are arranged so that they are equally spaced apart in the circumferential direction of the base 511. In other words, the pair of holes 513 are arranged so that an imaginary line connecting them passes through the center of the base 511. The arrangement direction of the pair of holes 513 corresponds to the front-to-rear direction in this disclosure.

Each hole 513 penetrates the base 511 in its thickness direction (vertical direction). The opening of each hole 513 is approximately rectangular. A corresponding guide portion 82 is fitted into each hole 513. Therefore, light emitted from the pair of light sources 81 is guided to the outside of the housing 5 via each of the pair of guide portions 82.

The rear cover 52 has multiple insertion holes 520 into which multiple (e.g., four) connection pieces 101 of the mounting portion 10 fixed to the board 2 are inserted (see FIG. 1). The multiple connection pieces 101 are electrically connected to the circuit module provided on the board 2. The multiple connection pieces 101 are inserted to the extent that their tips sufficiently protrude from the rear side (the installation surface 55 side) of the rear cover 52. The multiple connection pieces 101 can be mechanically and electrically connected to contact portions of the mounting base (not shown) fixed to the structure X1. In short, the mounting portion 10 is not simply a mechanical connection to the mounting base, but also a part that electrically connects with the electrical wires (power supply lines and signal lines) on the rear side of the structure X1 and stably positions the board 2 relative to the rear cover 52. This positioning includes not only radial positioning of the board 2 but also vertical positioning of the board 2.

The rear cover 52 also has a recess 521 (see Figure 1) on its surface (bottom surface) facing the circuit board 2 for accommodating the upper part of the smoke detector 4 mounted on the circuit board 2. In other words, the smoke detector 4 is stably positioned by the recess 521.

Furthermore, the rear cover 52 has, on one surface (lower surface) facing the substrate 2, multiple control plates (walls) 522 (see Figure 3A: four in the illustrated example) that control the flow of gas within the flow path 6. Each control plate 522 is formed in a generally arc shape when viewed from the substrate 2 side. Each control plate 522 protrudes (downward) toward the base 511 of the front cover 51. When viewed from the substrate 2 side, the four control plates 522 are arranged at generally equal intervals along the circumferential direction of the rear cover 52 near the peripheral edge of the rear cover 52. The four control plates 522 control (guide) the airflow in the internal space SP1 of the housing 5 so that the gas flowing through the flow path 6 more easily flows toward the thermal detection element 30 or the smoke detection unit 4. The number of control plates 522 is not particularly limited and may be one.

(2.3) Circuit Board The circuit board 2 is a printed circuit board. Mounted on the circuit board 2 are a heat detection unit 3, a smoke detection unit 4, a display unit 8, a control unit 9, a communication unit 11, and other circuit modules (not shown). The other circuit modules include a lighting circuit that lights the light source 81 of the display unit 8 and the optical element 41 of the smoke detection unit 4, and a power supply circuit that generates operating power for various circuits using power supplied from a commercial power source or the like.

As shown in Figure 3A, the substrate 2 is formed in a generally circular shape overall. Figure 3A is a plan view of the detector 1 as seen from below, with some parts (substrate 2, control panel 522, and smoke detection unit 4) visible.

In this embodiment, at least four thermal detection elements 30 of the thermal detection unit 3 are surface-mounted on the first surface 21 (front surface) of the substrate 2. The first surface 21 is the top surface (see Figure 1). Here, as an example, the smoke detection unit 4 is also arranged on the same plane as the first surface 21 of the substrate 2. The smoke detection unit 4 is mounted on the first surface 21 of the substrate 2. The labyrinth portion 43 (described below) of the smoke detection unit 4 has an engagement claw on the underside of its bottom, which is fixed by engaging with an engagement hole formed in the substrate 2. The light source 81 of the display unit 8 is also mounted on the first surface 21 of the substrate 2.

The control unit 9 and the multiple electronic components that make up the circuit module are mounted on the first surface 21 or second surface 22 of the substrate 2. The control unit 9 and the multiple electronic components that make up the circuit module do not have to be mounted only on the substrate 2; for example, some or all of the components may be mounted on another mounting board disposed around the substrate 2.

Hereinafter, the surface of the substrate 2 opposite the first surface 21 (top surface) may be referred to as the second surface 22 (bottom surface). In Figure 3A, the substrate 2 is shown in perspective, with its second surface 22 visible. The thermal detection element 30, light source 81, and smoke detection unit 4 are actually mounted on the first surface 21 behind the second surface 22, but for ease of explanation, these are also shown in perspective in Figure 3A. In particular, in Figure 3A, the optical element 41 and light receiving element 42 arranged within the labyrinth portion 43 of the smoke detection unit 4 are shown simplified with dots.

Of the first surface 21 and the second surface 22, the first surface 21 corresponds to the surface closer to the installation surface 55. Therefore, it can be said that the heat detection element 30 and the smoke detection unit 4 are both located on the surface of the substrate 2 closer to the installation surface 55.

The structure of substrate 2 will be described in detail below. As shown in Figure 3A, substrate 2 has a circular main body 200 and multiple (eight in the illustrated example) extension portions that extend from the edge of main body 200 in a direction away from the center of main body 200. Hereinafter, the eight extension portions will be referred to as a pair of first extension portions 201, a pair of second extension portions 202, a pair of third extension portions 203, and a pair of fourth extension portions 204.

The smoke detection unit 4 is located on the top surface of the main body 200. Meanwhile, the four heat detection elements 30 and two light sources 81 are located on the six extensions (201, 202, 203), respectively.

A pair of first extension portions 201 extend away from each other from the left and right edges of the main body portion 200. A corresponding connection piece 101 is disposed on the top surface of each first extension portion 201. Each first extension portion 201 also has a narrower small piece portion Y1 at its tip. A corresponding thermal detection element 30 is disposed on the top surface of each small piece portion Y1.

The pair of second extension portions 202 extend away from each other from the front and rear edges of the main body portion 200. The extension amount of the second extension portion 202 is less than the extension amount of the other extension portions. A corresponding light source 81 is disposed on the upper surface of each second extension portion 202.

When viewed from the underside of the substrate 2, the pair of third extension portions 203 extend away from each other from positions slightly offset counterclockwise from the front and rear edges of the main body portion 200. Specifically, the front third extension portion 203 is located to the left of the front second extension portion 202, and the rear third extension portion 203 is located to the right of the rear second extension portion 202. Like the first extension portion 201, each third extension portion 203 has a narrower small piece portion Y1 at its tip. A corresponding thermal detection element 30 is located on the upper surface of each small piece portion Y1.

When viewed from the underside of the substrate 2, the pair of fourth extension portions 204 extend away from each other from positions slightly offset clockwise from the front and rear edges of the main body portion 200. Specifically, the front fourth extension portion 204 is located to the right of the front second extension portion 202, and the rear fourth extension portion 204 is located to the left of the rear second extension portion 202. A corresponding connection piece 101 is located on the top surface of each fourth extension portion 204.

In other words, the substrate 2 has a two-fold symmetric shape, which becomes symmetric when rotated 180 degrees around its center.

A through-hole 31 (see FIG. 3B) with a rectangular opening is provided in each of the pair of first extension portions 201 and the pair of third extension portions 203, on which the four thermal detection elements 30 are arranged. FIG. 3B is an enlarged view of the circle surrounded by the dotted line (imaginary line) in FIG. 3A, as an example. The through-hole 31 is located inside the thermal detection elements 30 (toward the center of the internal space SP1). The thermal detection elements 30 and the through-hole 31 are located adjacent to each other. By providing such through-holes 31 near each thermal detection element 30, the area occupied by the substrate 2 around the thermal detection element 30 can be reduced, preventing heat from the thermal detection element 30 from being transferred through the substrate 2 and causing a drop in temperature. In other words, the through-holes 31 improve thermal insulation. It is desirable that the opening area of the through-hole 31 be larger than the surface area of the thermal detection element 30 (e.g., the surface area of the substrate 2 as viewed from above).

(2.4) Heat Detection Unit and Smoke Detection Unit As described above, the heat detection unit 3 has four heat detection elements 30 mounted on the first surface 21 of the substrate 2 (only one is shown in FIG. 4 ). The number of heat detection elements 30 is not particularly limited and may be one, but is preferably at least two or more. In this embodiment, the heat detection elements 30 are chip thermistors that detect the heat of the gas flowing in from the openings 7 and are surface-mounted on the substrate 2. Each heat detection element 30 is arranged to face a different opening 7. The positional relationship of the heat detection elements 30 with respect to the flow path 6 and the openings 7 will be explained in detail in the section "(2.7) Layout of Heat Detection Unit" below.

The heat detection unit 3 is electrically connected to the control unit 9 via pattern wiring formed on the substrate 2. Each heat detection element 30 outputs an electrical signal (detection signal) to the control unit 9. In other words, the control unit 9 monitors the resistance value of each heat detection element 30, which can change depending on the temperature rise, through the electrical signal output from each heat detection element 30.

In addition to the thermal detection element 30, the thermal detection unit 3 may further include an amplifier circuit that amplifies the electrical signal from the thermal detection element 30 and a conversion circuit that performs analog-to-digital conversion, or amplification and conversion may be performed on the circuit module side.

The smoke detection unit 4 is disposed in the center of the internal space SP1 and is configured to detect smoke. Specifically, the smoke detection unit 4 is disposed on the upper surface of the main body 200 of the substrate 2, and its upper portion is housed in the accommodation recess 521 of the rear cover 52. The smoke detection unit 4 is, for example, a photoelectric sensor that detects smoke. As shown in FIG. 4 , the smoke detection unit 4 has an optical element 41 that emits light, a light-receiving element 42 that receives the light emitted from the optical element 41, and a labyrinth portion 43. The optical element 41 is, for example, an LED (Light Emitting Diode). The light-receiving element 42 is, for example, a photodiode. The labyrinth portion 43 is formed inside a case having a flat, approximately cylindrical outer shell. The case of the smoke detection unit 4 has multiple openings on its outer surface that introduce gas into the labyrinth portion 43 and is structured to prevent external light from entering the interior.

The optical element 41 and the light-receiving element 42 are positioned within the labyrinth portion 43 so that they do not face each other. In other words, the light-receiving surface of the light-receiving element 42 is positioned off the optical axis C1 (see Figure 3A) of the light emitted by the optical element 41.

In the event of a fire or other incident, smoke may enter the housing 5 through the opening 7 in the housing 5 and be introduced into the labyrinth portion 43. If there is no smoke in the labyrinth portion 43, very little of the light emitted by the optical element 41 reaches the light-receiving surface of the light-receiving element 42. On the other hand, if there is smoke in the labyrinth portion 43, the light emitted by the optical element 41 is scattered by the smoke, and some of the scattered light reaches the light-receiving surface of the light-receiving element 42. In other words, the smoke detection unit 4 receives the light emitted by the optical element 41 that has been scattered by the smoke using the light-receiving element 42.

The light-receiving element 42 of the smoke detection unit 4 is electrically connected to the control unit 9. The smoke detection unit 4 transmits an electrical signal (detection signal) indicating a voltage level corresponding to the amount of light received by the light-receiving element 42 to the control unit 9. The control unit 9 converts the amount of light in the detection signal received from the smoke detection unit 4 into a smoke concentration and determines whether a fire has occurred. The control unit 9 may use the light amount directly for threshold determination. The smoke detection unit 4 may also convert the amount of light received by the light-receiving element 42 into a smoke concentration and then transmit a detection signal indicating a voltage level corresponding to the smoke concentration to the control unit 9.

The smoke detection unit 4 may further include an amplifier circuit that amplifies the electrical signal from the light-receiving element 42 and a conversion circuit that performs analog-to-digital conversion, or amplification and conversion may be performed on the circuit module side. Furthermore, the number of optical elements 41 for smoke detection is not limited to one and may be multiple.

(2.5) Display Unit The display unit 8 has a pair of light sources 81 and a pair of guide units 82. Each light source 81 is configured as a packaged LED, with at least one LED chip mounted in the center of the mounting surface of a flat mounting board, for example. As described above, each light source 81 is mounted on the board 2. Each guide unit 82 is a translucent portion formed in a substantially L-shape. Each guide unit 82 faces the corresponding light source 81 on the board 2 and has an incident surface onto which light emitted from the light source 81 is incident. Each guide unit 82 has an exit surface from which light incident from the incident surface is emitted to the outside of the guide unit 82. The exit surface of each guide unit 82 is exposed through a corresponding hole 513 in the front cover 51.

The display unit 8 is an operating light that notifies the outside world of the operating status of the detector 1. Under normal circumstances (when monitoring for a fire), the lighting circuit of the circuit module turns off the light source 81 under the control of the control unit 9. When it is determined that a fire has occurred, the lighting circuit of the circuit module starts flashing or lighting the light source 81 under the control of the control unit 9. The lighting circuit between the control unit 9 and the display unit 8 is not shown in Figure 4.

(2.6) Control Unit The control unit 9 is configured, for example, by a microcontroller mainly composed of a CPU (Central Processing Unit) and a memory. In other words, the control unit 9 is realized by a computer having a CPU and a memory, and the computer functions as the control unit 9 when the CPU executes a program stored in the memory. Here, the program is pre-recorded in the memory, but it may also be provided via a telecommunications line such as the Internet or recorded on a recording medium such as a memory card.

The control unit 9 is configured to control the communication unit 11 and circuit modules (lighting circuits, power supply circuits, etc.).

The control unit 9 is also configured to receive detection signals from the heat detection unit 3 and the smoke detection unit 4 and determine whether a fire has occurred. Specifically, the control unit 9 individually monitors the detection signals from the four heat detection elements 30 of the heat detection unit 3, and determines that a fire has occurred if it finds even one heat detection element 30 whose signal level (equivalent to the resistance value) contained in the detection signal exceeds (or falls below) a threshold. The control unit 9 also monitors the detection signal from the smoke detection unit 4, and determines that a fire has occurred if the signal level (equivalent to the amount of light received by the light receiving element 42 or smoke concentration) contained in the detection signal exceeds a threshold.

When the control unit 9 determines that a fire has occurred based on heat detection or smoke detection, it transmits a signal notifying the occurrence of a fire to the receiver and fire alarm of the automatic fire alarm system via the communication unit 11. The communication unit 11 is a communication interface for communicating with the receiver and fire alarm, for example, via a wired connection. The communication unit 11 is communicatively connected to the receiver and fire alarm via the connecting piece 101 of the mounting unit 10, the connector portion of the mounting base, and a signal line wired on the back side of the structure X1. Furthermore, when the control unit 9 determines that a fire has occurred, it outputs a control signal to the lighting circuit of the circuit module to flash or light the light source 81 of the display unit 8 (operation light).

(2.7) Arrangement of the Heat Detector The arrangement of the heat detector 3 of this embodiment will now be described.

In this embodiment, as described above, the thermal detection element 30 of the thermal detection unit 3 is a chip thermistor mounted on the first surface 21 of the substrate 2. This allows the detector 1 to be made smaller (particularly thinner) as a whole. Furthermore, compared to lead-type thermistors, the cost of the thermistor itself and its mounting costs can be kept low.

Furthermore, in this embodiment, at least a portion of the first surface 21 (surface) of the substrate 2 is exposed to the flow path 6. Here, the smoke detection unit 4 is disposed in the center of the first surface 21, and the central portion of the internal space SP1 of the housing 5 is largely occupied by the smoke detection unit 4. The flow path 6 essentially corresponds to the space surrounding the central portion (smoke detection unit 4) of the internal space SP1. In other words, the flow path 6 is roughly donut-shaped. Therefore, in this embodiment, of the entire area of the first surface 21 of the substrate 2, the peripheral area other than the mounting area of the smoke detection unit 4 is exposed to the flow path 6. The peripheral area also includes the top surfaces of the eight extension portions (201-204) described above.

By exposing the peripheral area of the first surface 21 of the substrate 2 to the flow path 6 in this way, the four thermal detection elements 30 in the first extension portion 201 and the third extension portion 203, while being chip thermistors, are more likely to be exposed to the gas flowing through the flow path 6.

That is, when heated gas rises from below due to the outbreak of a fire, for example, it is introduced into the housing 5 through the multiple openings 7 and flows through the flow path 6. At that time, the heat detection element 30 detects heat at a temperature equivalent to that of a fire, and the detector 1 can quickly determine that a fire has occurred. As a result, the detector 1's heat detection performance can be further improved while also being made smaller.

The detector 1 of this embodiment also includes a smoke detection unit 4, which is located in the center of the internal space SP1 at the back of the flow path 6. In other words, the flow path 6 is a common flow path through which both heat and smoke can pass. Therefore, if the gas introduced into the housing 5 through the multiple openings 7 has a smoke concentration above a specified level, smoke can also be detected. This allows for the detector 1 as a whole to be made smaller while improving its fire detection performance.

In this embodiment, each thermal detection element 30, which is a chip thermistor, is positioned to face a different opening 7. In FIG. 1, the thermal detection element 30 on the left side is positioned to face one opening 7 on the left side, and the thermal detection element 30 on the right side is positioned to face another opening 7 on the right side. Each thermal detection element 30 is positioned to fit within the approximately rectangular opening area 70 of the corresponding opening 7 when viewed from the external space SP2 side (see FIGS. 1 and 5). In other words, the area of the thermal detection element 30 projected onto the opening area 70 is contained within the opening area 70. This increases the likelihood that at least a portion of the thermal detection element 30 will be exposed to gas entering through the opening 7, compared to when the thermal detection element 30 is positioned outside the opening area 70, i.e., hidden behind the cylindrical body 510 or the crosspiece 512 of the housing 5.

In particular, in this embodiment, as shown in FIG. 5 , each thermal detection element 30, which is a chip thermistor, is located at the center of the opening region 70 in the direction (vertical direction) perpendicular to the first surface 21 when viewing the opening region 70 from the external space SP2 side. In other words, the positional relationship between the opening 7 and the substrate 2 is defined so that each thermal detection element 30 is located at the center of the opening region 70. This positional relationship is adjusted, for example, by the protrusion amount of the rib 514 (see FIG. 1 ) that protrudes from the back side of the base 511 of the front cover 51 and contacts the substrate 2, and the insertion amount of the connecting piece 101 of the mounting portion 10. This positional relationship further increases the likelihood that the thermal detection element 30 will be exposed to gas that has entered through the opening 7, compared to, for example, when the thermal detection element 30 is located closer to one end (closer to the upper or lower end) of the opening region 70.

Furthermore, in this embodiment, each thermal detection element 30 is not simply positioned to the side of the smoke detection unit 4, but is positioned near the opening 7. In other words, if the flow path 6 is divided into a first path 61 located on the opening 7 side and a second path 62 connected to the first path 61 and located near the center of the internal space SP1, each thermal detection element 30, which is a chip thermistor, is located within the first path 61 (see Figure 1). Therefore, the heat detection responsiveness of the detector 1 can be improved compared to, for example, a case in which the chip thermistor is located within the second path 62. As mentioned above, while the flow path 6 is schematically illustrated with arrows in Figure 1, in reality, the first path 61 corresponds to the outer half of the gap surrounding the smoke detection unit 4 in the internal space SP1, and the second path 62 corresponds to the inner half of the gap.

In the thickness direction (vertical direction) of the substrate 2, the center P1 of the internal space of the labyrinth portion 43 is preferably located vertically between the thermal detection element 30, which is a chip thermistor, and the installation surface 55 (see FIG. 1). In other words, the thermal detection element 30 is located vertically below the center P1. In FIG. 3A, the optical element 41 and the light-receiving element 42 arranged within the labyrinth portion 43 are schematically illustrated by dots. In this embodiment, the heights of the optical element 41 and the light-receiving element 42 are the same, and the intersection of the optical axis C1 of the optical element 41 and the optical axis C2 of the light-receiving element 42 approximately coincides with the center P1, for example.

The height positions of the optical element 41 and the light-receiving element 42 and the orientation of the optical axes C1 and C2 are not particularly limited, as long as the optical axis C1 does not intersect with the light-receiving surface of the light-receiving element 42. For example, the height of either the optical element 41 or the light-receiving element 42 may be lower than the height of the other. Furthermore, the optical axes C1 and C2 do not have to intersect with each other. In this case, the midpoint between the optical axes C1 and C2 may approximately coincide with the center P1 when viewed from the side of the smoke detection unit 4.

By locating center P1 between the heat detection element 30 and installation surface 55 in this way, smoke (gas) that passes through the heat detection element 30 can be effectively guided to the smoke detection unit 4, taking into account the characteristic that an updraft is generated when heated gas flows through flow path 6 within housing 5. Therefore, in a detector 1 that detects not only heat but also smoke, the fire detection performance can be further improved while the detector 1 as a whole can be made smaller.

(3) Modifications The above embodiment is merely one of various embodiments of the present disclosure. The above embodiment can be modified in various ways depending on the design, etc., as long as the object of the present disclosure can be achieved. Furthermore, functions similar to those of the sensor 1 according to the above embodiment may be embodied in a control method for the sensor 1, a computer program, a non-transitory recording medium on which a computer program is recorded, or the like.

Below, we will list some variations of the above embodiment. The variations described below can be applied in appropriate combinations. Note that below, the above embodiment may also be referred to as the "basic example."

The control unit 9 of the sensor 1 in the present disclosure includes a computer system. The computer system is primarily composed of a processor and memory as hardware. The processor executes a program stored in the memory of the computer system to realize the functions of the control unit 9 of the sensor 1 in the present disclosure. The program may be pre-recorded in the memory of the computer system, provided via a telecommunications line, or provided on a non-transitory recording medium readable by the computer system, such as a memory card, optical disk, or hard disk drive. The processor of the computer system is composed of one or more electronic circuits, including a semiconductor integrated circuit (IC) or a large-scale integrated circuit (LSI). The integrated circuits, such as ICs and LSIs, are referred to by different names depending on the degree of integration, and include integrated circuits known as system LSIs, very large-scale integrations (VLSIs), or ultra-large-scale integrations (ULSIs). Furthermore, field-programmable gate arrays (FPGAs), which are programmed after the LSI is manufactured, or logic devices capable of reconfiguring the connections within the LSI or the circuit partitions within the LSI, can also be used as processors. Multiple electronic circuits may be integrated into a single chip, or may be distributed across multiple chips. Multiple chips may be integrated into a single device, or may be distributed across multiple devices. The computer system referred to here includes a microcontroller having one or more processors and one or more memories. Therefore, the microcontroller is also composed of one or more electronic circuits, including semiconductor integrated circuits or large-scale integrated circuits.

Furthermore, it is not essential for the detector 1 that multiple functions of the control unit 9 of the detector 1 are concentrated within a single housing; the components of the detector 1 may be distributed across multiple housings. Furthermore, at least some of the functions of the detector 1, for example, may be realized by the cloud (cloud computing) or the like. Conversely, as in the basic example, multiple functions of the detector 1 may be concentrated within a single housing.

(3.1) Modification 1
The sensor 1A of this modified example (modified example 1) will be described below with reference to Fig. 6. Components that are generally common to the sensor 1 of the basic example will be assigned the same reference numerals, and their description may be omitted as appropriate. Fig. 6 shows a schematic cross-sectional view of the sensor 1A.

Detector 1A differs from the basic example in that it is equipped with an airflow adjustment unit Z1 within internal space SP1. Airflow adjustment unit Z1 extends from the lower edge of the cylindrical body 510 on the front cover 51 of the housing 5 toward the smoke detection unit 4. When viewed from the top and bottom, airflow adjustment unit Z1 is a roughly donut-shaped plate member. Airflow adjustment unit Z1 may be formed integrally with the front cover 51, or it may be a separate member from the front cover 51 that is fixed to the front cover 51 by screws or the like.

The airflow adjustment section Z1 extends straight along the substrate 2 for a certain distance from the edge of the opening 7 toward the inside of the housing 5. However, the airflow adjustment section Z1 is inclined toward the installation surface 55 from midway toward the center of the internal space SP1.

In other words, in detector 1A, the airflow adjustment unit Z1 is provided, so the opening cross-sectional area of the first path 61 is set smaller than the opening cross-sectional area of the second path 62. Therefore, gas that enters the flow path 6 through the opening 7 can be encouraged to flow from the narrow space of the first path 61 toward the wide space of the second path 62.

In particular, because the airflow adjustment section Z1 is inclined midway toward the installation surface 55, the second path 62 widens in the direction toward the installation surface 55 as it moves from the first path 61 toward the center. Therefore, when heated gas flows through the flow path 6 inside the housing 5, an ascending air current is generated, and smoke (gas) that passes through the thermal detection element 30 can be effectively guided to the smoke detection unit 4.

(3.2) Modification 2
The sensor 1B of this modified example (modification example 2) will be described below with reference to Fig. 7. Components that are generally common to the sensor 1 of the basic example will be assigned the same reference numerals, and their description may be omitted as appropriate. Fig. 7 shows a schematic cross-sectional view of the sensor 1B.

Detector 1B differs from the basic example in that the smoke detection unit 4 is mounted on the second surface 22 of the substrate 2, rather than the first surface 21. The heat detection element 30 is mounted on the first surface 21, just like the basic example.

In the housing 5 of this detector 1B, the smoke detection unit 4 is mounted on the second surface 22 (bottom surface), so the front cover 51 has a storage recess 515 that houses the smoke detection unit 4. Specifically, the base 511 of the front cover 51 is formed so that its center is convex downward. In the basic example, the back cover 52 has a storage recess 521 that houses the upper part of the smoke detection unit 4 (see Figure 1).

The base 511 has a hole 5111 on the peripheral wall of its convex portion 5110, which allows gas (smoke) to enter the housing 5.

The flow path 6 is configured to split into two paths, an upper flow path 6X and a lower flow path 6Y, separated by the substrate 2. Heated gas passing through the upper flow path 6X passes through the thermal detection element 30. Part of the gas passing through the lower flow path 6Y passes through the through-hole 31 in the substrate 2 (see Figure 3B) and rises to the upper flow path 6X, passing through the thermal detection element 30. The remainder of the gas passing through the lower flow path 6Y heads directly toward the smoke detection unit 4 in the center.

(3.3) Modification 3
The sensor 1C of this modified example (modified example 3) will be described below with reference to Figures 8A and 8B. Components that are generally common to the sensor 1 of the basic example will be assigned the same reference numerals, and their description may be omitted as appropriate. Note that Figure 8A is a perspective view of sensor 1C as seen from below, and Figure 8B is a plan view of sensor 1C as seen from below, with part (only substrate 2) being see-through.

As an example, detector 1C is a P-type (Proprietary-type) heat detector that transmits a fire signal to the outside using a proprietary type communication method. Like the basic example, detector 1C is equipped with a heat detection unit 3, but unlike the basic example, it does not have a smoke detection unit 4. In other words, detector 1C determines the occurrence of a fire or other incident solely by detecting heat.

Detector 1C also differs from the basic example in that it has three heat detection elements 30 (compared to four in the basic example).

As shown in Figure 8B, the substrate 2 of the detector 1C is generally diamond-shaped when viewed from below. Two of the three thermal detection elements 30 are surface-mounted on the first surface 21 (top surface) of the diamond-shaped substrate 2. The two thermal detection elements 30 are respectively arranged at diagonal positions in the left-right direction on the first surface 21 (top surface). Specifically, the substrate 2 has a pair of protrusions 23 that protrude outward (at a slight angle relative to the left-right direction) on both edges of the diagonal positions. A corresponding thermal detection element 30 is arranged on the top surface of each protrusion 23. The other thermal detection element 30 is arranged on the top surface of the central part of the substrate 2.

Also, as with the basic example, through holes 31 are provided near each thermal detection element 30 to improve thermal insulation. However, for the thermal detection element 30 located in the center of the substrate 2, two semicircular through holes 31 are arranged to sandwich the thermal detection element 30 between them.

The front cover 51 of the detector 1C has one inlet (vertical hole) 7B and two auxiliary ports (vertical holes) 56 in its base 511. The two auxiliary ports 56 are located near the left and right edges of the base 511, and the inlet 7B is located in the center of the base 511. The inlet 7B and the two auxiliary ports 56 each penetrate the base 511 of the front cover 51 in its thickness direction. The two auxiliary ports 56 located near the left and right edges of the base 511 have approximately crescent-shaped openings, and the inlet 7B located in the center of the base 511 has a approximately circular opening. The pair of protrusions 23 of the substrate 2 face each other in a one-to-one correspondence with the two auxiliary ports 56, and the center of the substrate 2 faces the central inlet 7B. As a result, as shown in Figure 8B, the convex portion 23 and the center of the substrate 2 are exposed from the two auxiliary ports 56 and the inlet port 7B, respectively. Therefore, rising heated gas enters the housing 5 through the two auxiliary ports 56 and the inlet port 7B, and then flows through the through-hole 31 to the first surface 21 (top surface) side. Therefore, the heat detection element 30 is easily exposed not only to gas flowing in from the opening 7 (side port 7A: horizontal hole), but also to gas flowing in from the two auxiliary ports 56 and the inlet port 7B.

Even with this configuration, it is possible to further improve fire detection performance while also achieving a smaller overall size (particularly a thinner design) of the detector 1C.

(3.4) Modification 4
A sensor 1D of this modified example (modified example 4) will be described below with reference to Figures 9A and 9B. Components that are generally common to sensor 1 of the basic example will be assigned the same reference numerals, and their description may be omitted as appropriate. Note that Figure 9A is a perspective view of sensor 1D as seen from below, and Figure 9B is a plan view of sensor 1D as seen from below, with part (only substrate 2) being see-through.

As an example, detector 1D is an R-type heat detector that transmits a fire signal to the outside using the so-called R-type (Record-type) communication method. Like the basic example, detector 1D is equipped with a heat detection unit 3, but unlike the basic example, it does not have a smoke detection unit 4. In other words, detector 1D determines the occurrence of a fire or other similar event solely by detecting heat, just like detector 1C of variant 3.

Detector 1D also differs from the basic example in that it has five heat detection elements 30 (compared to four in the basic example).

As shown in Figure 9B, the substrate 2 of sensor 1D has a shape somewhat similar to that of the substrate 2 of the basic example. Specifically, the substrate 2 of sensor 1D has a circular main body 200 and multiple (six in the illustrated example) extension portions that extend from the edges of the main body 200 in a direction away from the center of the main body 200. Hereinafter, the six extension portions will be referred to as a pair of first extension portions 201, a pair of second extension portions 202, and a pair of third extension portions 203. One of the five thermal detection elements 30 is located in the center of the main body 200, and the remaining four thermal detection elements 30 and two light sources 81 are located on the six extension portions (201, 202, 203), respectively.

A pair of first extension portions 201 extend away from each other from the left and right edges of the main body portion 200. Each first extension portion 201 has a narrower small piece portion Y1 at its tip. A corresponding thermal detection element 30 is disposed on the top surface of each small piece portion Y1.

The pair of second extension portions 202 extend away from each other from the front and rear edges of the main body portion 200. The extension amount of the second extension portion 202 is less than the extension amount of the other extension portions. A corresponding light source 81 is disposed on the upper surface of each second extension portion 202.

When viewed from the underside of the substrate 2, the pair of third extension portions 203 extend away from each other from positions slightly offset counterclockwise from the front and rear edges of the main body portion 200. Specifically, the front third extension portion 203 is located to the left of the front second extension portion 202, and the rear third extension portion 203 is located to the right of the rear second extension portion 202. Like the first extension portion 201, each third extension portion 203 has a narrower small piece portion Y1 at its tip. A corresponding thermal detection element 30 is located on the upper surface of each small piece portion Y1.

In other words, the substrate 2 of the sensor 1D has a two-fold symmetric shape, which becomes symmetric when rotated 180 degrees around its center.

Also, as with the basic example, through holes 31 are provided near each thermal detection element 30 to improve thermal insulation. However, for the thermal detection element 30 located in the center of the substrate 2, two semicircular through holes 31 are arranged to sandwich that thermal detection element 30. Also, as with the basic example, a pair of guide portions 82 of the display unit 8 are exposed on the front cover 51 of the detector 1D.

The front cover 51 of the sensor 1D has one inlet (vertical hole) 7B and two auxiliary ports (vertical holes) 57 in its base 511. The two auxiliary ports 57 are located near the left and right edges of the base 511, and the inlet 7B is located in the center of the base 511. The two auxiliary ports 57 and the inlet 7B each penetrate the base 511 of the front cover 51 in its thickness direction. The two auxiliary ports 57 located near the left and right edges of the base 511 have approximately rectangular openings, and the inlet 7B located in the center of the base 511 has an approximately circular opening. The tips of the small pieces Y1 in the pair of first extensions 201 of the substrate 2 face each other in a one-to-one correspondence with the two auxiliary ports 57 on the left and right, respectively, and the center of the substrate 2 faces the central inlet 7B. As a result, the tip of the small piece Y1 and the center of the substrate 2 are exposed from the two auxiliary ports 57 and the inlet port 7B, respectively, as shown in Figure 9B. Therefore, rising heated gas enters the housing 5 through the two auxiliary ports 57 and the inlet port 7B, and then flows through the through-hole 31 to the first surface 21 (top surface) side. Therefore, the heat detection element 30 is easily exposed not only to gas flowing in from the opening 7 (side port 7A: horizontal hole), but also to gas flowing in from the two auxiliary ports 57 and the inlet port 7B.

Even with this configuration, it is possible to further improve fire detection performance while also achieving a smaller overall size (particularly a thinner design) of the detector 1D.

(3.5) Modification 5
The sensor 1E of this modified example (modification example 5) will be described below with reference to Figures 10A and 10B. Components that are generally common to the sensor 1 of the basic example will be assigned the same reference numerals, and their description may be omitted as appropriate. Note that Figure 10A is a perspective view of the sensor 1E as seen from below, and Figure 10B is a plan view of the sensor 1E as seen from below, with a portion (only the substrate 2) being see-through.

Detector 1E is, as an example, a fire alarm that outputs an alarm or other sound when a fire occurs. Like the basic example, detector 1E is equipped with a heat detection unit 3, but unlike the basic example, it does not have a smoke detection unit 4. In other words, detector 1E, like detector 1C of modification 3 and detector 1D of modification 4, determines the occurrence of a fire or other event by detecting heat alone.

Detector 1E also differs from the basic example in that it is equipped with a speaker that outputs sounds such as an alarm, an acoustic circuit, etc. Detector 1E is, as an example, a battery-powered fire alarm. Therefore, detector 1E has a battery and a storage space for the battery. In detector 1E, the operating unit U1 is exposed on the front of the front cover 51.

Operation unit U1 accepts external operation. Operation unit U1 can be pushed upward by a user's finger or other means. Operation unit U1 is a translucent, disc-shaped member. Operation unit U1 is positioned opposite the operation light inside the housing 5. Operation unit U1 is also configured to press a push button switch inside the housing 5 when pressed. For example, if operation unit U1 is pressed while an alarm is sounding, the output of the alarm sound will be stopped. Furthermore, operation unit U1 lights up when detector 1E is in operation or when the battery runs out, etc. Operation unit U1 can also be used to perform operation tests, etc.

Detector 1E also differs from the basic example in that it has three heat detection elements 30 (compared to four in the basic example).

As shown in Figure 10B, the circuit board 2 of sensor 1E has an inverted Y shape when viewed from below. Sensor 1E houses or supports relatively large components, such as a speaker, battery, and operating unit U1, within the housing 5, so to avoid these components being housed or supported, the circuit board 2 has an inverted Y shape that saves space.

Specifically, the substrate 2 of the sensor 1E has a circular main body 200 with a notched left side, and multiple (three in the illustrated example) extensions that extend from the edge of the main body 200 in a direction away from the center of the main body 200. Hereinafter, the three extensions will be referred to as extension pieces 205. Three thermal detection elements 30 are respectively arranged on the three extension pieces 205.

Of the three extension pieces 205, the front extension piece 205 extends from the front edge of the main body 200, and a corresponding thermal detection element 30 is located on the upper surface of its tip. Of the three extension pieces 205, the rear two extension pieces 205 extend from positions slightly offset to the left and right from the rear edge of the main body 200, and two corresponding thermal detection elements 30 are located on the upper surface of each of their tips.

Also, as with the basic example, through holes 31 (three in total) are provided near the inner side of each thermal detection element 30 to improve thermal insulation.

The front cover 51 of the detector 1E has one auxiliary port (vertical hole) 58 in its base 511. The auxiliary port 58 is located near the front edge of the base 511. The auxiliary port 58 penetrates the base 511 of the front cover 51 in its thickness direction. The auxiliary port 58 has a substantially rectangular opening. The tip of the front extension piece 205 of the three extension pieces 205 faces the auxiliary port 58. As a result, the tip of the front extension piece 205 is exposed from the auxiliary port 58, as shown in FIG. 10B . Therefore, rising heated gas enters the housing 5 through the auxiliary port 58 and further flows through the through-hole 31 to the first surface 21 (top surface). This makes the thermal detection element 30 susceptible to gas flowing in from the auxiliary port 58 as well as gas flowing in from the opening 7 (side port 7A: horizontal hole).

Even with this configuration, it is possible to further improve fire detection performance while also achieving a smaller overall size (particularly a thinner design) for the detector 1E.

(3.6) Other Modified Examples The detector 1 (combined fire detector) of the basic example differs from modified examples 3 to 5 in that it does not have a vertical hole in the front cover 51. However, similar to modified examples 3 to 5, the detector 1 (combined fire detector) may have one or more auxiliary ports (vertical holes) 59 (two in the illustrated example) in the front cover 51, as shown in FIG. 11 .

In the basic example, the thermal detection element 30 is mounted on the first surface 21 (top surface) of the substrate 2. However, the thermal detection element 30 may also be mounted on the second surface 22 (bottom surface) of the substrate 2. Alternatively, some of the multiple thermal detection elements 30 may be mounted on the first surface 21 and the rest on the second surface 22. Furthermore, for example, both the thermal detection element 30 and the smoke detector 4 may be mounted on the second surface 22 (bottom surface) of the substrate 2.

In the basic example, there is one through-hole 31 adjacent to one thermal detection element 30, but as shown in Modifications 3 and 4, there may be two or more through-holes 31. For example, multiple through-holes 31 may be provided surrounding one thermal detection element 30.

In the basic example, the thermal detection element 30 is mounted on the first surface 21 of the substrate 2, and the through-holes 31 are arranged adjacent to it. However, even if the thermal detection element 30 is mounted on the second surface 22 of the substrate 2, it is desirable that the through-holes 31 be arranged adjacent to it.

In the basic example, the substrate 2 is composed of a single printed circuit board. However, the substrate 2 may also be divided into two or more printed circuit boards. However, it is desirable that the divided printed circuit boards be arranged on the same plane.

In the basic example, the opening 7 is a horizontal hole formed in the peripheral wall of the housing 5. However, the opening 7 referred to in this disclosure may not be a horizontal hole, but may instead correspond to the inlet (vertical hole) 7B in Modifications 3 to 5, the auxiliary ports (vertical holes) 56 to 58, and the auxiliary port (vertical hole) 59 described above.

(Embodiment 2)
A sensor 1F according to this embodiment will be described below with reference to Figures 12A and 12B. The sensor 1F according to this embodiment differs from the sensors (1, 1A to 1E) of embodiment 1 (including modifications) in that it further includes a shielding portion V1. Hereinafter, components substantially similar to those of embodiment 1 will be assigned common reference numerals and descriptions thereof will be omitted as appropriate. The shielding portion V1 of this embodiment may also be applied to the sensors (1, 1A to 1E) of embodiment 1 as appropriate.

Note that detector 1F shown in Figures 12A and 12B is, as an example, a P-type heat detector, similar to detector 1C of Modification 3 in Embodiment 1 (Figures 8A and 8B). Detector 1F, like detector 1C of Modification 3 in Embodiment 1, is a heat detector that does not include a smoke detection unit 4 and determines the occurrence of a fire or the like by detecting heat only.

In this embodiment, the thermal detection element 30 (chip thermistor) is also positioned so that it fits within the opening area 70 of the opening 7 (side opening 7A: horizontal hole) when viewed from the external space SP2 side. The shielding portion V1 is configured to block a portion of the opening area 70 on the external space SP2 side of the thermal detection element 30 (chip thermistor).

The shielding section V1 has a pair of pillars V11. Here, the shielding section V1 is composed of a pair of pillars V11. Each pillar V11 is elongated in the vertical direction (here, for example, the thickness direction of the substrate 2). Each pillar V11 is formed integrally with the front cover 51 of the housing 5. Specifically, the first end (upper end) of each pillar V11 is connected to the cylindrical body 510 of the housing 5, and the second end (lower end) of each pillar V11 is connected to the base 511. As a result, each pillar V11 extends from the upper edge to the lower edge of the opening 7 (side opening 7A).

When viewing the opening area 70 from the external space SP2 side, the pair of pillars V11 are arranged with a predetermined distance L1 between them in a direction D1 (here, the left-right direction) perpendicular to the arrangement direction of the rear cover 52 and the front cover 51. Below, as an example, the rear cover 52 corresponds to the first cover and the front cover 51 corresponds to the second cover, but the reverse may also be true, with the rear cover 52 corresponding to the second cover and the front cover 51 corresponding to the first cover.

Here, as an example, the predetermined distance L1 is a distance specified so that a test finger cannot be inserted. The test finger may be, for example, a dummy finger as specified in Appendix 4, Section 1 (2) (H) of Japan's Electrical Appliance and Material Safety Act.

When viewing the opening region 70 from the external space SP2 side, the thermal detection element 30 is disposed between the pair of pillars V11 in direction D1 (see Figure 12A). In other words, the thermal detection element 30 is exposed from between the pair of pillars V11.

In this way, by further providing the shielding portion V1, the sensor 1F is less likely to be impeded by the inflow of heat from the opening 7, while reducing the possibility of, for example, a person's finger or a tool unintentionally coming into contact with the chip thermistor.

As shown in Figure 12B, each pillar V11 has a guide surface V2 that guides the airflow from the external space SP2 toward the thermal detection element 30 (chip thermistor). Here, the cross section of each pillar V11 cut along the horizontal direction has a roughly semi-elliptical shape, and this curved surface corresponds to the guide surface V2. The tip of this semi-elliptical shape faces the thermal detection element 30. This further reduces the possibility that the shielding portion V1 will block heat inflow from the opening 7.

Next, we will explain variant 1 of this embodiment. In the example of Figures 12A and 12B described above, the number of pillars V11 in the shielding section V1 is two, but the number of pillars in the shielding section V1 is not particularly limited. Figures 13A and 13B show sensor 1G of variant 1. Sensor 1G of variant 1 differs from sensor 1F in that the number of pillars in the shielding section V1 is three.

As an example, detector 1G of variant 1 is a P-type heat detector. Note that the convex portion 23 on the substrate 2 of detector 1F protrudes slightly obliquely relative to the radial direction of the housing 5 when viewed in the vertical direction (see Figure 12B), whereas the convex portion 23 on the substrate 2 of detector 1G protrudes outward in the radial direction of the housing 5 (see Figure 13B).

The shielding section V1 of the sensor 1G has three pillars (a pair of first pillars V12 on the left and right and a second pillar V13 in the middle). Here, the shielding section V1 is composed of three pillars. Each of the pair of first pillars V12 and second pillars V13 is elongated in the vertical direction (here, for example, the thickness direction of the substrate 2). Each of the pair of first pillars V12 and second pillars V13 is formed integrally with the front cover 51 of the housing 5. Specifically, the first end (upper end) of each pillar is connected to the cylindrical body 510 of the housing 5, and the second end (lower end) of each pillar is connected to the base 511. As a result, each pillar extends from the upper edge to the lower edge of the opening 7.

When viewing the opening area 70 from the external space SP2 side, each of the pair of first pillars V12 and the second pillar V13 are positioned with a predetermined distance L2 between them in direction D1 (here, the left-right direction). Here, as an example, the predetermined distance L2 is also a distance specified to prevent a test finger from entering.

The thermal detection element 30 is disposed between a pair of first pillars V12 in direction D1 when viewing the opening region 70 from the external space SP2 side (see Figure 13A). However, when viewing the opening region 70 from the external space SP2 side, the thermal detection element 30 is positioned so that it overlaps with the second pillar V13. In other words, the thermal detection element 30 is hidden behind the second pillar V13 and is in an invisible position.

In this way, by providing the shielding portion V1 with three pillars, the detector 1G is less likely to be impeded by the inflow of heat from the opening 7, while further reducing the possibility of a person's finger or tool coming into contact with the chip thermistor.

As shown in FIG. 13B, each of the pair of first columns V12 has a guide surface V2 that guides the airflow from the external space SP2 toward the thermal detection element 30 (chip thermistor). Here, the cross-sectional shape of each of the pair of first columns V12 taken horizontally is a long, approximately racetrack shape that follows the outer edge of the housing 5, and has semicircular curved surfaces on both the left and right sides as guide surfaces V2. This further reduces the possibility that the shielding portion V1 will block the inflow of heat from the opening 7. Note that the cross-sectional shape of the second column V13 taken horizontally is approximately rectangular, but it may also have a roughly racetrack shape like the first column V12 and have guide surfaces V2.

Note that Figure 13C shows another example of the detector 1G of variant 1. In this example, each of the pair of first pillars V12 has a substantially trapezoidal cross section cut along the horizontal direction. Each first pillar V12 is configured so that of the two parallel sides of the trapezoid, the shorter side faces the thermal detection element 30 and the longer side faces the external space SP2. In particular, each first pillar V12 has a first surface V121 facing the middle second pillar V13 and a second surface V122 opposite the first surface V121, which are inclined toward the thermal detection element 30. The inclination angle of the second surface V122 with respect to the radial direction of the housing 5 is greater than the inclination angle of the first surface V121. The cross section of the middle second pillar V13 cut along the horizontal direction has a bullet shape that is elongated in the radial direction of the housing 5, and the side facing the thermal detection element 30 is semicircular. In this other example, the first surface V121, the second surface V122, and the end surface with a semicircular cross section correspond to the guide surface V2. In other words, in this other example, each of the pair of first columns V12 has a guide surface V2. In this other example, the provision of the guide surface V2 further reduces the possibility that the shielding portion V1 will block heat inflow from the opening 7.

Next, we will explain Variation 2 of this embodiment. Figures 14A to 14C and Figure 15 show sensor 1H of Variation 2. Sensor 1H of Variation 2 is, as an example, an R-type heat sensor. The protrusion 23 on the substrate 2 of sensor 1H protrudes outward along the radial direction of the housing 5.

The shielding portion V1 in the sensor 1H of variant 2 has a pair of first protrusions V14 and one second protrusion V15. Here, the shielding portion V1 is composed of a pair of first protrusions V14 and a second protrusion V15. Each of the pair of first protrusions V14 protrudes from the rear cover 52 (first cover) that covers the substrate 2 from one direction (here, from above) in the thickness direction of the substrate 2, toward the front cover 51 (second cover). The front cover 51 covers the substrate 2 from the direction opposite to the one direction in the thickness direction of the substrate 2 (here, from below). The second protrusion V15 protrudes from the front cover 51 toward the rear cover 52. Each of the pair of first protrusions V14 and second protrusions V15 is elongated in the vertical direction (here, for example, the thickness direction of the substrate 2).

As shown in Figure 15, the pair of first protrusions V14 are formed integrally with the rear cover 52. Specifically, the pair of first protrusions V14 protrude downward continuously from the peripheral edge of the underside of the rear cover 52. Note that the tips of the pair of first protrusions V14 do not contact the front cover 51, leaving a gap between them.

When viewing the opening region 70 from the external space SP2 side, the pair of first protrusions V14 are spaced a predetermined distance L3 apart in the direction D1. Here, as an example, the predetermined distance L3 is also a distance defined to prevent a test finger from entering. When viewing the opening region 70 from the external space SP2 side, the thermal detection element 30 is positioned between the pair of first protrusions V14 in the direction D1 (see Figure 14A).

The second protrusion V15 is positioned centrally between the pair of first protrusions V14 in direction D1. In other words, each of the pair of first protrusions V14 is positioned offset from the second protrusion V15 in direction D1 when viewing the opening region 70 from the external space SP2 side. This further reduces the possibility that the shielding portion V1 will block heat inflow from the opening 7.

The second protrusion V15 is formed integrally with the front cover 51. Specifically, the second protrusion V15 protrudes upward continuously from the peripheral edge of the top surface of the front cover 51. The tip of the second protrusion V15 does not contact the upper edge of the opening 7, leaving a gap between it and the upper edge.

As shown in FIG. 14A, the second protrusion V15 is located at the same position as the chip thermistor in direction D1 when viewing the opening region 70 from the external space SP2 side. However, the amount of protrusion of the second protrusion V15 is specified so that at least a portion of the chip thermistor is exposed. Specifically, the amount of protrusion is specified so that the tip of the second protrusion V15 does not extend beyond the upper surface of the chip thermistor. Note that, as an example, the tip of the second protrusion V15 is located below the lower surface of the substrate 2, and the thermal detection element 30 is exposed between the pair of first protrusions V14 without being hidden behind the second protrusions V15.

By specifying the protrusion amount of the second protrusion V15 so that at least a portion of the chip thermistor is exposed in this way, heat inflow from the opening 7 is less likely to be impeded, while the possibility of a person's finger or tool coming into contact with the chip thermistor is reduced.

As shown in Figure 14B, each of the pair of first protrusions V14 also has a guide surface V2. Here, the cross-sectional shape of each of the pair of first protrusions V14 taken along the horizontal direction is an elongated ellipse that extends along the radial direction of the housing 5, and curved surfaces are provided on both the left and right sides as guide surfaces V2. This further reduces the possibility that the shielding portion V1 will block the inflow of heat from the opening 7. In particular, the relatively small width dimension of each first protrusion V14 further reduces the possibility that the inflow of heat will be blocked.

On the other hand, as shown in FIG. 14C, the second protrusion V15 also has a guide surface V2. The second protrusion V15 is formed in a generally triangular shape when viewed along the direction in which the pair of first protrusions V14 are aligned. In particular, the second protrusion V15 has a curved surface V150 that is concave and inclined in a generally arc shape on the side of the internal space SP1 when viewed along the direction in which the pair of first protrusions V14 are aligned. This curved surface V150 also corresponds to the guide surface V2. When the hot air current collides with the guide surface V2, it can be guided toward the chip thermistor located above the second protrusion V15.

In this way, by providing the shielding portion V1 with three protrusions, the sensor 1H is less likely to be impeded by the inflow of heat from the opening 7, while further reducing the possibility of a person's finger or tool coming into contact with the chip thermistor.

The shielding portion V1 may have, for example, another first protrusion V14 between a pair of first protrusions V14. The other first protrusion V14 and the second protrusion V15 may protrude so that their tips face each other. In this case, as with the second protrusion V15, it is desirable that the protrusion amount of the other first protrusion V14 be specified so that at least a portion of the chip thermistor is exposed.

Next, we will explain variant 3 of this embodiment. Figure 16 shows detector 1I of variant 3. Detector 1I of variant 3 is an R-type heat detector, as an example.

The shielding portion V1 of the sensor 1I has a pair of first protrusions V16 formed integrally with the rear cover 52, similar to the pair of first protrusions V14 of the sensor 1H of Variation 2. The pair of first protrusions V16 protrude from the rear cover 52 toward the front cover 51. The heat detection element 30 is positioned between the pair of first protrusions V16 in direction D1 when viewing the opening area 70 from the external space SP2 side.

The shielding portion V1 of the sensor 1I further has a pair of second protrusions V17. Each of the pair of second protrusions V17 is formed integrally with the front cover 51, similar to the second protrusions V15 of the sensor 1H of variant 2. The pair of second protrusions V17 protrude from the front cover 51 toward the rear cover 52. However, the pair of second protrusions V17 protrude such that their tips face the tips of the pair of first protrusions V16 in a one-to-one relationship. In other words, there is a gap between each first protrusion V16 and the opposing second protrusion V17.

The shielding portion V1 of the detector 1I also has a pillar V18. Like the second pillar V13 of the detector 1G of variant 1, the pillar V18 is formed integrally with the front cover 51 of the housing 5. The heat detection element 30 is positioned so that it overlaps with the pillar V18 when the opening area 70 is viewed from the external space SP2 side. In other words, the heat detection element 30 is hidden behind the pillar V18 and is in an invisible position.

When viewing the opening area 70 from the external space SP2 side, each of the pair of first protrusions V16 and the pillar V18 are spaced a predetermined distance L4 apart in the direction D1. Here, as an example, the predetermined distance L4 is also a distance specified to prevent a test finger from entering.

In this way, by providing the shielding portion V1 with four protrusions and one pillar, the sensor 1I is less likely to be impeded by heat inflow from the opening 7, while further reducing the possibility of a person's finger or tool coming into contact with the chip thermistor.

Although not shown in the figure, it is desirable that the shielding portion V1 of the sensor 1I also have an induction surface V2.

Next, we will explain variant 4 of this embodiment. Figures 17A and 17B show detector 1J of variant 4. Detector 1J of variant 4 is, as an example, an R-type heat detector.

The shielding portion V1 of detector 1J has only one pillar V19. Like the second pillar V13 of detector 1G of variant 1, pillar V19 is formed integrally with the front cover 51 of the housing 5. The heat detection element 30 is located so that it overlaps with pillar V19 when viewing the opening area 70 from the external space SP2 side. In other words, the heat detection element 30 is hidden behind pillar V19 and is in an invisible position.

As shown in Figure 17B, pillar V19 has a guide surface V2. Here, the cross-sectional shape of pillar V19 cut along the horizontal direction is tapered toward the internal space SP1, and this tapered surface corresponds to guide surface V2. In addition, the cross-sectional shape of pillar V19 is semicircular on both the left and right sides, and these surfaces on both the left and right sides also correspond to guide surface V2.

Thus, even though sensor 1J has only one pillar V19, it is able to prevent heat from entering through opening 7 and reduce the possibility of a person's finger or tool coming into contact with the chip thermistor. If prioritizing reducing the possibility of a person's finger or tool coming into contact with the chip thermistor, it is desirable for the number of protrusions or pillars on shielding portion V1 to be two or more, as with sensors 1F-1I.

(Embodiment 3)
A detector 1K according to this embodiment will be described below with reference to FIGS. 18A to 18C. Components substantially similar to those in the first embodiment are designated by common reference numerals and will not be described again. As described below, the detector 1K according to this embodiment differs from the detectors (1, 1A to 1E) of the first embodiment (including modifications) in that the outer surface 53 has a tapered first surface 531. The tapered first surface 531 of this embodiment may also be applied to the detectors (1, 1A to 1E) of the first embodiment or the detectors (1F to 1J) of the second embodiment. The detector 1K shown in FIGS. 18A to 18C is an R-type heat detector, for example. Similar to the detector 1C of the third modification of the first embodiment, the detector 1K is a heat detector that does not include a smoke detector 4 and determines the occurrence of a fire or the like solely by detecting heat. Similar to the detector 1H of the second modification of the second embodiment, the detector 1K includes multiple sets of shielding portions V1.

The opening 7 of the sensor 1K according to this embodiment has an inlet 7B, similar to the sensor 1C (see Figures 8A and 8B) and the sensor 1D (see Figures 9A and 9B) described in embodiment 1. That is, the opening 7 has an inlet 7B in addition to six side openings (horizontal holes) 7A. The inlet 7B is provided on the outer surface 53 (the underside of the front cover 51) of the housing 5, on the side opposite the structure X1 to which the sensor 1K is attached. Here, for example, the inlet 7B is provided in the center of the outer surface 53. The inlet 7B penetrates the front cover 51 in its thickness direction. The inlet 7B has a substantially circular opening.

In sensor 1K, as shown in FIG. 18B, a portion of substrate 2 is exposed from inlet 7B. Specifically, substrate 2 has a hole 25 penetrating through its center in the thickness direction. Hole 25 has a substantially circular opening. Hole 25 is positioned so as to roughly overlap inlet 7B. Substrate 2 has a pair of protrusions 26 protruding toward each other at the edge of hole 25. The tips of the pair of protrusions 26 are exposed from inlet 7B. A thermal detection element 30 (chip thermistor) is also provided on the upper surface of each protrusion 26 of substrate 2. In short, sensor 1K has multiple thermal detection elements 30 (six in the illustrated example) provided near side opening (horizontal hole) 7A, as well as two thermal detection elements 30 near inlet 7B. In addition, the substrate 2 has approximately triangular through-holes 31 near each thermal detection element 30 to prevent heat from the thermal detection element 30 from being transmitted through the substrate 2 and causing the temperature of the thermal detection element 30 to drop.

The opening 7 of the detector 1K has an inlet 7B, which allows it to detect the heat of the gas flowing in through the inlet 7B, thereby improving responsiveness in heat detection.

The outer surface 53 of the sensor 1K of this embodiment has a first surface 531 around the inlet 7B and a second surface 532 located outside the first surface 531. In particular, as shown in FIG. 18C , the first surface 531 is tapered at a different inclination angle from the second surface 532, tapering in a direction (upward) toward the structure X1 as it approaches the inlet 7B. Note that, as an example, the outer surface 53 further has a third surface 533. The third surface 533 is located outside the first surface 531 and inside the second surface 532. The first surface 531 to the third surface 533 all have a doughnut shape when the outer surface 53 is viewed from the front. Regarding the radial dimensions of the outer surface 53, for example, the second surface 532 is the largest, the third surface 533 is next largest, and the first surface 531 is the smallest, but this is not particularly limited.

The inclination angle θ1 of the first surface 531 with respect to the horizontal plane is, for example, 23°. The inclination angle θ2 of the second surface 532 with respect to the horizontal plane is, for example, 0° to 1°. The inclination angle θ3 of the third surface 533 with respect to the horizontal plane is, for example, 8°.

In this way, in the detector 1K according to this embodiment, the outer surface 53 has a first surface 531 and a second surface 532, which further promotes the flow of heat into the inlet 7B in the event of a fire (see the arrow in Figure 18C). In particular, in the detector 1K, the outer surface 53, including the third surface 533, is inclined in two stages, which more effectively promotes the flow of heat into the inlet 7B.

Regular inspections of this type of detector are required by law to check whether they are functioning properly (for example, once every six months). As shown in Figure 19A, an inspection worker 600 uses a specified (heating) tester 900 to perform a heating inspection of the thermal detection element 30 of detector 1K, which is installed on structure X1 (the ceiling in the illustrated example).

The tester 900 has a heat source 910 such as a hand warmer, a roughly cylindrical main body 920 with an open top that houses the heat source 910, and a support rod 930 that supports the main body 920. During inspection, the main body 920 is positioned so that it covers the base 511 and opening 7 of the front cover 51 of the detector 1K from below. If the heat detection element 30 and other components are normal, the detector 1K will receive heat flow from the heat source 910 and operate in the same way as if it had detected a fire.

As explained in the first embodiment, the thermal detection element 30 is a chip thermistor mounted on the substrate 2, which allows the detector (1, 1A-1K) to be made smaller (particularly thinner) as a whole. However, as the detector becomes smaller, there is a possibility that the stability of the position of the tester 900 relative to the detector may be compromised during inspection.

The housing 5 of the sensor 1K according to this embodiment has multiple (e.g., six) protrusions W1 (see Figures 18A and 18B; however, only four are shown in Figure 18A). The multiple protrusions W1 protrude from the edge (here, the upper edge) of the opening 7 in a direction (e.g., downward) away from the side of the structure X1 to which the sensor 1K is attached. The multiple protrusions W1 are arranged at equal intervals around the circumference of the housing 5, for example, when viewed from below.

The multiple protrusions W1 are configured to come into contact with the peripheral edge 901 (see Figure 19B) of the tester 900 when the tester 900, which is used to perform a heating inspection of the thermal detection element 30, is positioned to cover the housing 5. Providing multiple protrusions W1 in this manner ensures that the tester 900 is stably positioned relative to the housing 5. In other words, the protrusions W1 are more likely to make point contact with the peripheral edge 901, which can reduce rattling compared to when the housing 5 makes surface contact with the peripheral edge 901 without the protrusions W1.

Here, multiple protrusions W1 protrude downward from the periphery of the lower end of the cylindrical body 510. The multiple protrusions W1 are located at the same position along the circumferential direction of the housing 5 so as to correspond one-to-one with the multiple crosspieces 512. Specifically, each protrusion W1 is formed integrally with a portion (upper portion) of the corresponding crosspiece 512. In other words, each protrusion W1 also functions as a portion that reinforces the corresponding crosspiece 512. However, each protrusion W1 does not necessarily have to function as a portion that reinforces the crosspiece 512. Each protrusion W1 may be located at a position offset from the crosspiece 512 along the circumferential direction of the housing 5.

The number of protrusions W1 is not particularly limited and may be, for example, one. Even if there is only one protrusion W1, the housing 5 can be positioned more stably than when it is in surface contact with the peripheral edge 901 of the tester 900.

Figure 20 also shows detector 1L, a modified example of embodiment 3. Detector 1L of this modified example also has a first surface 531 in which the outer surface 53 is tapered. Detector 1L is, as an example, a P-type heat detector. In particular, like detector 1G of modified example 1 of embodiment 2, detector 1L has two sets of shielding portions V1 each having three pillars (a pair of first pillars V12 on the left and right and a second pillar V13 in the middle). In Figure 20, only one of the two sets of shielding portions V1 is shown, with the remaining set of shielding portions V1 being located on the back side.

The sensor 1L also has multiple (e.g., four) protrusions W1 (see FIG. 20; only three are shown) configured to come into contact with the peripheral edge 901 (see FIG. 19B) of the tester 900. At least one of the four protrusions W1 is formed integrally with a portion (upper portion) of the second pillar V13 in the center of the shielding portion V1, so as to function as a portion that reinforces the second pillar V13. In other words, the four protrusions W1 of the sensor 1L are located in the same positions along the circumferential direction of the housing 5 as the two crosspieces 512 and two second pillars V13 (including the second pillar V13 of the shielding portion V1 on the opposite side from the illustrated shielding portion V1), so as to correspond one-to-one to each of them.

(Embodiment 4)
A detector 1M according to this embodiment will be described below with reference to Figures 21A and 21B. Hereinafter, components substantially similar to those in embodiment 1 will be assigned the same reference numerals and descriptions thereof will be omitted where appropriate. The detector 1M shown in Figures 21A and 21B is an R-type heat detector, as an example. Similar to the detector 1C of modification 3 in embodiment 1, the detector 1M is a heat detector that does not include a smoke detector 4 and determines the occurrence of a fire or the like by detecting heat only. The detector 1M also includes multiple sets of shielding sections V1 each having three pillars.

Detector 1M further includes a mounting base 100B for installing its main body 100A on structure X1 (the ceiling in the illustrated example). The mounting base 100B may also be applied to the detectors of embodiment 1 (1, 1A-1E), the detectors of embodiment 2 (1F-1J), or the detectors of embodiment 3 (1K, 1L), as appropriate.

The mounting base 100B is generally formed in the shape of a flat cylinder with an open bottom. The mounting base 100B is fixed to the surface of the structure X1 by screws or the like. The structure X1 has holes for leading out the electrical wires (power supply lines, signal lines, etc.) on its back side. The mounting base 100B has a through-hole 103 (see Figure 21B) in its bottom 106 for passing the electrical wires leading out from the holes in the structure X1 toward the main body 100A.

Mounting base 100B also has an outer peripheral wall 104 and a flange 105 that protrudes outward from outer peripheral wall 104. Outer peripheral wall 104 is configured to fit into a recess formed by cylindrical body 510 and rear cover 52 (see Figure 1) on the upper side of main body 100A. While a detailed explanation is omitted, for example, when outer peripheral wall 104 is fitted into the recess of main body 100A and rotated clockwise about the axial direction, an engaged portion is provided on mounting base 100B that engages with an engaging portion of rear cover 52. Main body 100A is fixed to mounting base 100B by the engaging portion of rear cover 52 engaging with the engaged portion.

As shown in Figure 21A, when the main body 100A is fixed to the mounting base 100B, the outer surface of the flange 105 and the outer surface of the cylindrical body 510 are substantially flush with each other, making the sensor 1M an attractive sensor.

The above-mentioned mounting base 100B is a type of base unit that mounts the sensor 1M directly on the surface of the structure X1. However, as a modification of this embodiment, instead of the mounting base 100B, the sensor 1M may be provided with an embedded base 100C, as shown in Figures 22A and 22B. The embedded base 100C is a type of base unit that mounts the sensor 1M embedded in the structure X1.

The embedded base 100C has a base body 107 that is inserted into an embedding hole in the structure X1, and a decorative portion 108 that is formed integrally with the base body 107.

The base body 107 is formed in a flat cylindrical shape with an open bottom. The embedded base 100C also has a mounting bracket (the first mounting bracket T1 or the second mounting bracket T2 described below) for securing the embedded base 100C to the structure X1 when inserted into the hole in the structure X1. The base body 107 has a through-hole 110 (see Figure 22B) in its bottom 109 for passing electrical wires on the back side of the structure X1 toward the main body 100A.

The base body 107 has a recess 111 with an inner diameter slightly larger than the outer diameter of the body 100A. In other words, the body 100A can be accommodated within the recess 111. In this case, the recess 111 is deep enough that approximately half of the cylindrical body 510 in the vertical direction fits within the recess 111.

The decorative portion 108 protrudes outward from the lower end of the base body 107 in a flange-like shape. When the base body 107 is inserted into the hole in the structure X1, the decorative portion 108 is exposed and positioned below the surface of the structure X1.

Although a detailed explanation will be omitted, for example, when the main body 100A is fitted into the recess 111 of the base main body 107 and rotated clockwise in the axial direction, an engaged portion that engages with the engaging portion of the rear cover 52 is provided on the embedded base 100C. The main body 100A is fixed to the embedded base 100C by the engaging portion of the rear cover 52 engaging with the engaged portion.

As shown in Figure 22A, when the main body 100A is fixed to the embedded base 100C, the amount of protrusion from the surface of the structure X1 of the sensor 1M can be reduced, allowing it to be provided as a sensor with a good appearance.

Now, with reference to Figure 23A, we will explain the method of attaching the embedded base 100C to the structure X1 using a pair of first mounting brackets T1. The embedded base 100C has a pair of first mounting brackets T1. For ease of explanation, Figure 23A shows only the structure X1 in cross section. Each first mounting bracket T1 has a fixing screw T11 and a fixing piece T12 shaped like a partially bent leaf spring. The fixing piece T12 has a threaded hole into which the fixing screw T11 is threaded. The fixing piece T12 is temporarily fixed to the fixing screw T11 on the upper side of the base body 107, with the fixing screw T11 inserted from below into a through hole in the bottom 109 of the base body 107. In other words, the bottom 109 is sandwiched between the flat portion T120 of the fixing piece T12 and the head of the fixing screw T11.

When attaching the embedded base 100C to the structure X1, first loosen the fixing screws T11 with a tool such as a screwdriver to release the clamped state. In this state, the fixing pieces T12 can tilt inward along with the fixing screws T11 (see the imaginary lines in Figure 23A). The fixing pieces T12 are tilted inward, and the base body 107 is inserted into the hole X11 of the structure X1 while maintaining this state. Then, by tightening the fixing screws T11 with a tool such as a screwdriver, the fixing pieces T12 tilt outward, using the flat portions T120 that are in contact with the base body 107 as a fulcrum, until their tips T121 (point of application) come into contact with the back surface of the structure X1. Then, by further tightening the fixing screws T11, the structure X1 is clamped vertically between the tips T121 of the fixing pieces T12 and the decorative portion 108, thereby securing the embedded base 100C to the structure X1.

Next, a method for attaching the embedded base 100C to the structural body X1 using a pair of second mounting brackets T2 will be described with reference to Figure 23B. The embedded base 100C has a pair of second mounting brackets T2. For ease of explanation, Figure 23B shows only the structural body X1 in cross section. Each second mounting bracket T2 has a fixing screw T21 and a flat, rectangular, plate-shaped fixing piece T22. The fixing piece T22 has a threaded hole into which the fixing screw T21 is threaded. The fixing piece T22 is temporarily fixed to the fixing screw T21 on the upper side of the decorative part 108, with the fixing screw T21 inserted from below into a through hole in the decorative part 108.

When attaching the embedded base 100C to the structure X1, first loosen each fixing screw T21 with a tool such as a screwdriver and rotate them so that the tips of the fixing pieces T22 face inward. While maintaining this position, insert the base body 107 into the hole X11 of the structure X1. Then, tighten each fixing screw T21 with a tool such as a screwdriver, so that the tips of the fixing pieces T22 face outward, and the fixing pieces T22 descend toward the back surface of the structure X1, making general surface contact. Then, by further tightening each fixing screw T21, the structure X1 is sandwiched vertically between each fixing piece T22 and the decorative portion 108, and as a result, the embedded base 100C is fixed to the structure X1.

The first mounting bracket T1 and second mounting bracket T2 described above are merely examples, and the mounting brackets used to secure the embedded base 100C to the structure X1 are not limited to these. Furthermore, the mounting method described above is also merely an example, and is not limited to these.

(4) Summary As described above, the sensor (1, 1A-1M) according to the first aspect includes a substrate (2), a thermal detection element (30), and a housing (5). The housing (5) houses the substrate (2). The housing (5) has a flow path (6) provided in its internal space (SP1) through which gas flows, and an opening (7) connecting the flow path (6) to an external space (SP2) of the housing (5). The thermal detection element (30) is a chip thermistor mounted on the substrate (2) and detects the heat of the gas flowing in through the opening (7). According to the first aspect, because the thermal detection element (30) is a chip thermistor mounted on the substrate (2), the overall size of the sensor (1, 1A-1M) can be reduced.

Regarding the detector (1, 1A-1M) according to the second aspect, in the first aspect, it is preferable that at least a portion of the surface (e.g., first surface 21) of the substrate (2) is exposed to the flow path (6). According to the second aspect, the likelihood that the thermal detection element (30) will be exposed to the gas flowing through the flow path (6) can be increased, thereby further improving heat detection performance while also achieving miniaturization.

Regarding the detector (1, 1A-1M) according to the third aspect, in the first or second aspect, it is preferable that the chip thermistor be arranged so as to fit within the opening area (70) of the opening (7) when the opening area (70) is viewed from the external space (SP2) side. According to the third aspect, the likelihood that the thermal detection element (30) will be exposed to the gas flowing through the flow path (6) can be increased, thereby further improving heat detection performance while achieving miniaturization.

Regarding the sensor (1, 1A-1M) according to the fourth aspect, in the third aspect, the chip thermistor is preferably located in the following position. That is, when the opening area (70) is viewed from the external space (SP2) side, the chip thermistor is preferably located within the opening area (70) at the center of the opening area (70) in a direction perpendicular to the surface (e.g., first surface 21) of the substrate (2). According to the fourth aspect, the likelihood of the thermal detection element (30) being exposed to the gas flowing through the flow path (6) can be further increased compared to, for example, when the chip thermistor is located closer to one end of the opening area (70) in the above direction.

Regarding the sensor (1, 1A-1M) according to the fifth aspect, in any one of the first to fourth aspects, the flow path (6) includes a first path (61) located on the side of the opening (7) and a second path (62) connected to the first path (61) and located on the side of the center of the internal space (SP1). The chip thermistor is preferably located within the first path (61). According to the fifth aspect, the response to heat detection can be improved compared to, for example, when the chip thermistor is located within the second path (62).

Regarding the sensor (1, 1A-1M) according to the sixth aspect, in any one of the first to fifth aspects, the flow path (6) includes a first path (61) located on the opening (7) side and a second path (62) connected to the first path (61) and located on the central side of the internal space (SP1). The cross-sectional area of the opening of the first path (61) is preferably smaller than the cross-sectional area of the opening of the second path (62). According to the sixth aspect, gas that enters the flow path (6) through the opening (7) can be encouraged to flow from the first path (61) toward the second path (62).

Regarding the detector (1, 1A-1M) according to the seventh aspect, in the sixth aspect, it is preferable that the housing (5) has an installation surface (55) facing the structure (X1) to which the detector (1, 1A-1M) is attached. It is preferable that the second path (62) widens in a direction approaching the installation surface (55) as it moves from the first path (61) toward the central portion. According to the seventh aspect, it is possible to more effectively generate an airflow from the first path (61) toward the second path (62).

The detector (1, 1A-1M) according to the eighth aspect is preferably any one of the first to seventh aspects, further comprising a smoke detector (4) disposed in the center of the interior space (SP1) and configured to detect smoke. According to the eighth aspect, since the detector detects not only heat but also smoke, the overall size of the detector (1, 1A-1M) can be reduced while improving fire detection performance.

Regarding the detector (1, 1A-1M) according to the ninth aspect, in the eighth aspect, it is preferable that the smoke detection unit (4) be arranged on the same plane as the surface (e.g., first surface 21) of the substrate (2) on which the chip thermistor is mounted. According to the ninth aspect, the overall size of the detector (1, 1A-1M) can be reduced while further improving fire detection performance.

Regarding the detector (1, 1A-1M) according to the tenth aspect, in the eighth or ninth aspect, the housing (5) preferably has an installation surface (55) facing the structure (X1) to which the detector (1, 1A-1M) is attached. The smoke detector (4) is preferably disposed on the surface of the substrate (2) that is closer to the installation surface (55) than either the surface (e.g., the first surface 21) or the surface opposite the surface (e.g., the second surface 22). According to the tenth aspect, further miniaturization can be achieved compared to, for example, when the smoke detector (4) is disposed on the surface farther from the installation surface (55).

Regarding the detector (1, 1A-1M) according to the eleventh aspect, in any one of the eighth to tenth aspects, the housing (5) preferably has one or more walls (control plates 522) in the internal space (SP1). The one or more walls (control plates 522) preferably guide gas to the heat detection element (30) or the smoke detection unit (4). According to the eleventh aspect, fire detection performance can be further improved.

Regarding the sensor (1, 1A-1M) according to the twelfth aspect, in any one of the eighth to eleventh aspects, the housing (5) preferably has an installation surface (55) facing the structure (X1) to which the sensor (1, 1A-1M) is attached. The smoke detection unit (4) has an optical element (41) that emits light, a light-receiving element (42) that receives the light emitted from the optical element (41), and a labyrinth portion (43). Within the labyrinth portion (43), the optical element (41) and the light-receiving element (42) are arranged so as not to face each other. In the thickness direction (vertical direction) of the substrate (2), the center (P1) of the internal space of the labyrinth portion (43) is preferably located between the chip thermistor and the installation surface (55). According to the twelfth aspect, in a detector (1, 1A-1M) that detects not only heat but also smoke, it is possible to further improve fire detection performance while reducing the overall size of the detector (1, 1A-1M).

Regarding the sensor (1, 1A-1M) according to the thirteenth aspect, in any one of the first to twelfth aspects, the chip thermistor is preferably arranged so as to fit within the opening region (70) of the opening (7) when the opening region (70) is viewed from the external space (SP2) side. The sensor (1, 1A-1M) preferably further includes a shielding portion (V1) that blocks a portion of the opening region (70) on the external space (SP2) side of the chip thermistor. According to the thirteenth aspect, the provision of the shielding portion (V1) makes it difficult to impede the inflow of heat from the opening (7), while reducing the possibility of, for example, a person's finger or a tool unintentionally coming into contact with the chip thermistor.

Regarding the detector (1, 1A-1M) according to the fourteenth aspect, in the thirteenth aspect, it is preferable that the shielding portion (V1) has a guide surface (V2) that guides the airflow from the external space (SP2) toward the chip thermistor. According to the fourteenth aspect, the possibility that the shielding portion (V1) will block the inflow of heat from the opening (7) can be further reduced.

Regarding the sensor (1, 1A-1M) according to the fifteenth aspect, in the thirteenth or fourteenth aspect, the housing (5) preferably has a first cover (e.g., one of the front cover 51 and the rear cover 52) and a second cover (the other). The first cover covers the substrate (2) from one direction in the thickness direction of the substrate (2). The second cover covers the substrate (2) from the direction opposite to the one direction in the thickness direction. The shielding portion (V1) preferably has a first protrusion (V14, V16) protruding from the first cover toward the second cover, and a second protrusion (V15, V17) protruding from the second cover toward the first cover. The fifteenth aspect further reduces the likelihood of a person's finger or tool coming into contact with the chip thermistor while making it difficult for heat to flow in through the opening (7).

Regarding the sensor (1, 1A-1M) according to the sixteenth aspect, in the fifteenth aspect, the first protrusion (V14) is preferably positioned as follows. That is, when the opening area (70) is viewed from the external space (SP2) side, the first protrusion (V14) is preferably positioned offset from the second protrusion (V15) in a direction perpendicular to the alignment direction of the first cover and second cover. According to the sixteenth aspect, the possibility that the shielding portion (V1) will block heat inflow from the opening (7) can be further reduced.

Regarding the sensor (1, 1A-1M) according to the seventeenth aspect, in the fifteenth aspect, it is preferable that the first protrusion (V16) and the second protrusion (V17) protrude so that their tips face each other. According to the seventeenth aspect, the possibility of a person's finger or a tool coming into contact with the chip thermistor can be further reduced.

Regarding the sensor (1, 1A-1M) according to the 18th aspect, in any one of the 15th to 17th aspects, at least one of the first protrusions (V14, V16) and the second protrusions (V15, V17) (here, the second protrusion V15) is preferably as follows. That is, when the opening region (70) is viewed from the external space (SP2), the at least one protrusion is preferably located at the same position as the chip thermistor in a direction perpendicular to the arrangement direction of the first cover and the second cover. Furthermore, when the opening region (70) is viewed from the external space (SP2), the amount of protrusion of the at least one protrusion is preferably specified so that at least a portion of the chip thermistor is exposed. According to the 18th aspect, it is possible to further reduce the likelihood of a person's finger or tool coming into contact with the chip thermistor while making it difficult for heat to flow in through the opening (7).

Regarding the sensor (1, 1A-1M) according to the 19th aspect, in any one of the first to 18th aspects, the opening (7) preferably has an inlet (7B). The inlet (7B) is provided on the outer surface (53) of the housing (5) on the side opposite the structure (X1) to which the sensor (1, 1A-1M) is attached. According to the 19th aspect, the heat of the gas flowing in through the inlet (7B) can be detected, thereby improving responsiveness in heat detection.

Regarding the sensor (1, 1A-1M) according to the 20th aspect, in the 19th aspect, the outer surface (53) preferably has a first surface (531) around the inlet (7B) and a second surface (532) located outside the first surface (531). The first surface (531) is preferably tapered at an inclination angle different from that of the second surface (532), tapering toward the structure (X1) as it approaches the inlet (7B). According to the 20th aspect, heat flow into the inlet (7B) can be further promoted.

Regarding the detector (1, 1A-1M) according to the twenty-first aspect, in any one of the first to twentieth aspects, the housing (5) preferably has one or more protrusions (W1). The one or more protrusions (W1) protrude from the edge of the opening (7) in a direction away from the side of the structure (X1) to which the detector (1, 1A-1M) is attached. The one or more protrusions (W1) are preferably configured to contact the peripheral edge (901) of the tester (900) for performing a heating inspection of the thermal detection element (30) when the tester (900) is arranged to cover the housing (5). According to the twenty-first aspect, the provision of the protrusions (W1) ensures that the tester (900) is stably positioned relative to the housing (5). In other words, the protrusions (W1) are more likely to make point contact with the peripheral edge (901), which can reduce rattling compared to surface contact.

The configurations relating to aspects 2 to 12 are not essential for the sensors (1, 1A to 1E) and can be omitted as appropriate.

1, 1A to 1M Detector 2 Substrate 30 Heat detection element 4 Smoke detection section 41 Optical element 42 Light receiving element 43 Labyrinth section 5 Housing 51 Front cover (second cover)
52 Back cover (first cover)
53 Outer surface 531 First surface 532 Second surface 55 Installation surface 522 Control panel (wall)
6 Flow path 61 First path 62 Second path 7 Opening 7B Inlet 70 Opening area P1 Center SP1 Internal space SP2 External space V1 Shielding portion V14, V16 First projection V15, V17 Second projection V2 Guide surface W1 Convex portion X1 Structure 900 Tester 901 Peripheral portion

Claims (7)

A substrate;
A thermal detection element;
a housing that houses the substrate;
Equipped with
The housing includes:
a flow path provided in the internal space through which a gas flows;
an opening that connects the flow path and an external space of the housing;
a smoke detection unit disposed in the internal space and configured to detect smoke;
and
the heat detection element is a chip thermistor mounted on the substrate and configured to detect the heat of the gas flowing in through the opening ,
the smoke detector is disposed on a plane different from the surface of the substrate on which the chip thermistor is mounted.
sensor. A substrate;
A thermal detection element;
a housing that houses the substrate;
Equipped with
The housing includes:
a flow path provided in the internal space through which a gas flows;
an opening that connects the flow path and an external space of the housing;
a smoke detection unit disposed in the internal space and configured to detect smoke;
and
the heat detection element is a chip thermistor mounted on the substrate and configured to detect the heat of the gas flowing in through the opening,
The housing has one or more walls in the internal space that guide the gas to the heat detection element or the smoke detection unit.
sensor. A substrate;
A thermal detection element;
a housing that houses the substrate;
A sensor comprising:
The housing includes:
a flow path provided in the internal space through which a gas flows;
an opening that connects the flow path and an external space of the housing;
a smoke detection unit disposed in the internal space and configured to detect smoke;
and
the heat detection element is a chip thermistor mounted on the substrate and configured to detect the heat of the gas flowing in through the opening,
the housing has an installation surface facing a structure to which the sensor is attached,
The smoke detection unit
an optical element that emits light;
a light receiving element that receives light emitted from the optical element;
a labyrinth portion in which the optical element and the light receiving element are arranged so as not to face each other;
and
the center of the internal space of the labyrinth portion in the thickness direction of the substrate is between the chip thermistor and the installation surface;
sensor. A substrate;
A thermal detection element;
a housing that houses the substrate;
A sensor comprising:
The housing includes:
a flow path provided in the internal space through which a gas flows;
an opening that connects the flow path and an external space of the housing;
a smoke detection unit disposed in the internal space and configured to detect smoke;
and
the heat detection element is a chip thermistor mounted on the substrate and configured to detect the heat of the gas flowing in through the opening,
the housing has an installation surface facing a structure to which the sensor is attached,
the substrate has a first surface facing the installation surface and a second surface opposite to the first surface,
the chip thermistor is mounted on the first surface or the second surface, which is a mounting surface of the substrate,
the chip thermistor has a rectangular shape when viewed from a direction perpendicular to the mounting surface of the substrate, and has one surface facing the substrate in a thickness direction of the substrate.
sensor. the smoke detector is disposed on the same plane as the surface of the substrate on which the chip thermistor is mounted.
A sensor according to any one of claims 2 to 4. the housing has an installation surface facing a structure to which the sensor is attached,
The smoke detection unit is disposed on a surface of the substrate and a surface opposite to the surface, the surface being closer to the installation surface.
A sensor according to any one of claims 1 to 5. An automatic fire alarm system comprising the detector according to any one of claims 1 to 6 and a receiver that communicates with the detector.