JP6404510B1 - Heat sensor - Google Patents

Abstract

There is provided a heat detector capable of quickly and accurately detecting a temperature change state of air flowing into an air passage by a heat detecting element.
A sensor body includes a throttle portion that squeezes a cross-sectional area of an air passage in an air passage and allows air to flow, and a heat detection element is provided in a region immediately downstream of the throttle portion. Yes. Since the flow velocity increases when the air flow passes through the constricted portion provided in the air passage, a high-speed air flow is formed toward the heat detection element provided in the region immediately downstream thereof.
[Selection] Figure 4

Description

  The present invention relates to a heat detector having a heat detection element in an air passage extending from an air inlet on one end side to an air outlet on the other end side.

  2. Description of the Related Art There is known a heat detector that includes a heat detection element configured with a thermistor or the like in a space through which air passes (see, for example, Patent Document 1). Such a heat detector is, for example, a fire alarm device that outputs a warning sound or the like to notify a user of the occurrence of a fire when heat at an alarm level or higher is continuously detected by a heat detection element. It is configured.

  In such a heat sensor, for example, for the purpose of protecting the heat detection element provided projecting forward from the sensor body from an external impact or the like, the heat detection element is provided along the front surface of the sensor body. A protective cover is provided to cover the front. A space in the protective cover through which air passes is formed between the back surface of the protective cover and the front surface of the sensor body, and a heat detection element is provided in the space in the protective cover.

JP 2014-199632 A

  In the heat sensor as described above, it is desired to quickly and accurately detect the temperature change state of the air flowing into the space inside the protective cover. For this purpose, it is necessary to satisfactorily contact the heat detection element without radiating the air flowing into the space inside the protective cover as much as possible.

  In view of this situation, the main problem of the present invention is that in a heat sensor having a heat detection element in an air passage extending from an air inlet on one end side to an air outlet on the other end, air flowing into the air passage is appropriately It is in the point which provides the technique which can make it contact with a heat | fever detection element, and can detect the temperature change state of the air which flowed into the air path rapidly and correctly with a heat | fever detection element.

A first characteristic configuration of the present invention is a heat detector including a heat detection element in an air passage extending from an air inlet on one end side to an air outlet on the other end side,
A throttle portion that squeezes the cross-sectional area of the flow path in the air passage and allows air to flow;
The heat detection element is provided in a region immediately downstream of the throttle portion ;
An opening hole is formed in the wall portion defining the air passage to open the installation site of the heat detection element and the throttle portion .

According to this configuration, when air flows into the air passage from the air inlet, air flows from the air inlet to the air outlet in the air passage. If such an air flow is generated in the air passage, the flow velocity increases when the air flow passes through the constricted portion provided in the air passage. It forms toward the provided heat sensing element. Therefore, as much of the air that has flowed into the air passage as possible comes into contact with the heat detection element sequentially, so that the heat of the air can be positively transmitted to the heat detection element. Thereby, the temperature change state of the air flowing into the air passage in the heat detection element can be detected quickly and accurately.
Therefore, according to the present invention, in the heat detector having a heat detection element in the air passage extending from the air inlet on one end side to the air outlet on the other end side, the air flowing into the air passage is appropriately brought into contact with the heat detection element. Thus, it is possible to provide a technique capable of quickly and accurately detecting the temperature change state of the air flowing into the air passage with the heat detection element.
Further, according to the present configuration, for example, when the heat sensor is mounted on a ceiling surface or a diagonally downward wall surface in a posture in which the surface opposite to the air passage of the wall portion formed with the open hole is directed downward or obliquely downward However, when an upward flow of high-temperature air occurs in the event of a fire or the like, the upward flow of the high-temperature air generated in the vicinity of the heat detection element and throttle in the air passage through the open hole formed in the wall portion It can be made to flow into the installation part of a part and can be made to contact a heat | fever detection element positively. In addition, since the open hole that opens the air passage to the periphery extends from the installation site of the heat detection element toward the installation site of the throttle part on the lower side, the high-temperature air generated in the surroundings through the open hole The upward flow can be easily flown into the air passage, and furthermore, the high temperature air that has flowed in can be satisfactorily brought into contact with the heat detection element on the upper side.

  The second characteristic configuration of the present invention is that the throttle portion and the heat detection element are provided at a substantially central portion in the transverse direction of the air passage.

  According to this configuration, in the air passage, the throttle portion and the heat detection element are provided in the substantially central portion in the transverse direction of the air passage, so the air flowing through the air passage flows into the throttle portion in a well-balanced manner, The flow of air passing through the throttle portion comes into contact with the heat detection element provided in the region immediately downstream thereof stably and reliably. Therefore, since the heat of the air flowing into the air passage is stably transmitted to the heat detection element, the temperature change state of the air can be detected more quickly and accurately in the heat detection element.

According to a third characteristic configuration of the present invention, a protective cover that covers the front of the heat detection element provided to protrude from the front surface of the sensor main body is provided as a wall portion that defines the air passage . The inner space of the protective cover between the front surface of the sensor body and the rear surface of the protective cover is defined by the inner surfaces of the left and right side walls extending vertically on the left and right sides, so that the air inlet on the lower end side Is formed as the air passage extending in the up-down direction from the air outlet on the upper end side,
The open hole is formed in the protective cover.

The perspective view of the heat sensor of this embodiment The figure which shows the installation state of the heat sensor of this embodiment The figure which shows the installation state of the heat sensor of this embodiment Front view (a), side view (b), and bottom view (c) of the heat sensor of this embodiment Front view (a), side view (b), and bottom view (c) of heat sensor of another embodiment Front view (a), side view (b), and bottom view (c) of heat sensor of another embodiment Front view (a), side view (b), and bottom view (c) of heat sensor of another embodiment

An embodiment of the present invention will be described with reference to FIGS.
The heat sensor 100 according to the present embodiment is configured as a fire alarm device including a sensor body 1 and a heat detection element 6 disposed on the front surface 1a of the sensor body 1.
The heat sensor 100 can be mounted in a posture in which the front surface 1a faces the same direction as the ceiling surface or wall surface along the ceiling surface or wall surface facing the room. For example, when attached to the wall surface, as shown in FIG. 2, the front surface 1a can be attached to the vertical wall surface W in a posture that faces horizontally, but as shown in FIG. 3, the front surface 1a faces obliquely downward. It can also be attached to the wall W diagonally downward.

  In the present embodiment, the sensor body 1 is configured in a substantially rectangular parallelepiped shape, but may be configured in another shape such as a columnar shape or a disk shape. Moreover, the heat detection element 6 is comprised as temperature sensing parts, such as a well-known thermistor and a bimetal. The heat detection element 6 is installed so as to protrude forward from the front surface 1 a of the sensor body 1, and a lead wire portion extending rearward from the heat detection element 6 is an abbreviation of the front surface 1 a of the sensor body 1. Supported in the center.

  Although illustration is omitted, the sensor body 1 contains a control board, a power supply unit, and the like, and the control board or the like constitutes notification means for notifying the user. In addition, on the front surface 1a of the sensor main body 1, a speaker hole for outputting sound to the outside and a light emitting part of an LED lamp are arranged. Then, for example, when the heat detection element 6 continuously detects heat of an alarm level or higher, the notification means outputs an alarm sound or voice guidance from a speaker hole or flashes a light emitting unit. The fire is notified to the user. Further, an alarm stop button 4 for stopping the alarm when an alarm is output in the event of a fire or the like is provided below the front surface 1a of the sensor body 1, for example. Although details will be described later, the alarm stop button 4 is configured by using a lower end portion of a protective cover 20 described later.

  As shown in FIG. 1, the front surface 1 a of the sensor body 1 covers the front of the heat detection element 6 in order to protect the heat detection element 6 provided protruding from the front surface 1 a from external impact or the like. A protective cover 20 is provided. The protective cover 20 is disposed in front of the heat detection element 6, and is substantially bilaterally symmetric about a vertical axis that is substantially parallel to the front surface 1 a of the sensor body 1 and passes through the front side of the heat detection element 6. It is comprised by the rectangular plate-shaped member. By providing such a protective cover 20, a flat protection is provided between the rear surface 20a of the protective cover 20 and the front surface 1a of the sensor body 1, as shown in FIGS. 4B and 4C. A space in the cover is formed.

On the lower side of the heat sensor 100, an alarm stop button 4 is provided for stopping the alarm when an alarm is output in the event of a fire or the like. Specifically, the alarm stop button 4 is configured using the lower end portion of the protective cover 20. That is, a pressing element 4 </ b> A that protrudes toward the inside of the sensor body 1 is provided at a substantially central portion of the lower end portion of the protective cover 20. In the pressing operation of the alarm stop button 4, when the lower end portion of the protective cover 20 is pressed toward the front surface 1a of the sensor main body 1, the lower end portion of the protective cover 20 is bent, so that the substantially central portion thereof is bent. A switch element (not shown) provided in the sensor body 1 is pressed by the provided pressing element 4A, and predetermined processing such as alarm stop is executed.
In the front surface 1a of the sensor main body 1, a sleeve portion 1A surrounding the presser 4A is formed to protrude around the through hole of the presser 4A.

  As shown in FIG. 4, a support portion 21 for supporting the protective cover 20 on the sensor main body 1 is provided between the protective cover 20 and the sensor main body 1. The support portion 21 is formed integrally with the protective cover 20 so as to protrude rearward from the left and right side edges of the rear surface 20 a of the protective cover 20, and the tip portion thereof is the front surface of the sensor body 1. It is fixed to 1a.

Further, as shown in FIG. 4, side wall portions 22 extending in the vertical direction facing each other are provided on the left and right side portions of the space inside the protective cover formed between the protective cover 20 and the sensor body 1. It has been. Each of these side wall portions 22 is provided between the inner portion of each support portion 21 on the rear surface 20 a of the protective cover 20 and the front surface 1 a of the sensor body 1. Each of the side wall portions 22 is a plate-like portion that is perpendicular to the rear surface 20a of the protective cover 20 and the front surface 1a of the sensor body 1 and extends in the vertical direction and is perpendicular to the lateral width direction. Is formed.
That is, the space inside the protective cover between the front surface 1a of the sensor main body 1 and the rear surface 20a of the protective cover 20 is defined by the inner surfaces 22a of the left and right side wall portions 22 that extend vertically on both left and right sides, so that the lower end It is formed as an air passage A extending in the vertical direction from the air inlet Ai on the side to the air outlet Ao on the other end side.

In the heat sensor 100 having such an air passage A, when a high-temperature air upward flow F (see FIGS. 2 and 3) is generated around a fire in the event of a fire, the air flows through the air inlet Ai on the lower end side. Air flows into the air passage A from the surroundings, and air flows out from the air passage A to the surroundings through the air outlet Ao on the upper end side. From the air inlet Ai to the air outlet Ao in the air passage A. An upward flow of air will be generated.
Further, even when the heat sensor 100 is mounted along the ceiling surface so that the front surface 1a faces downward, for example, when the fire source is away from the heat sensor 100, FIG. 3, an air flow from the air inlet Ai toward the air outlet Ao may occur in the air passage A.

  A pair of fins 30 extending inward from the inner surfaces 22a of the left and right side wall portions 22 are provided in the air passage A in which an upward flow of air (air flow from the air inlet Ai toward the air outlet Ao) occurs when a fire occurs. Is provided. The pair of fins 30 are provided at the same height in the vertical direction, and are perpendicular to the rear surface 20a of the protective cover 20 and the front surface 1a of the sensor body 1 and in the transverse direction of the air passage A (that is, in the horizontal width direction). ). An inter-fin passage portion 30 </ b> A formed between the tip portions of the pair of fins 30 is formed at a substantially central portion in the transverse direction of the air passage A.

  As described above, the inter-fin passage portion 30A formed between the pair of fins 30 allows air to flow through the air passage A by reducing the cross-sectional area of the air passage A when an upward flow of air occurs in the air passage A. It functions as an aperture part to be turned on. Further, in the air passage A, the heat detection element 6 disposed at a substantially central portion in the transverse direction of the air passage A is provided in a region immediately above the inter-fin passage portion 30A.

  When an upward flow of air is generated in the air passage A at the time of a fire occurrence, the air flow passes through the inter-fin passage portion 30 </ b> A as a constricted portion formed between the pair of fins 30. A high-speed air flow is formed toward the heat detection element 6 provided in the region immediately above the portion 30A. Therefore, as much of the air that has flowed into the air passage A as possible comes into contact with the heat detection element 6 sequentially, and the heat of the air is positively transmitted to the heat detection element 6. As a result, the temperature change state of the air flowing into the air passage A in the heat detection element 6 can be detected quickly and accurately.

  In the air passage A, the inter-fin passage portion 30A and the heat detection element 6 are provided at a substantially central portion in the transverse direction of the air passage A, so the air flowing through the air passage A has a well-balanced inter-fin passage portion 30A. Flow into. Then, since the high-speed air flow that passes through the inter-fin passage portion 30A becomes a stable and substantially linear shape, the air flow is stably and surely applied to the heat detection element 6 provided in the region immediately downstream thereof. Can be contacted. As a result, the heat of the air flowing into the air passage A is stably transmitted to the heat detection element 6, and the temperature change state of the air can be detected more quickly and accurately by the heat detection element 6.

In the air passage A, the heat detection element 6 is provided at a position close to the rear surface 20a of the protective cover 20 as far as possible from the front surface 1a of the sensor body 1 having a large heat capacity in order to improve detection accuracy. As described above, the high-speed air flow generated in the inter-fin passage portion 30A of the air passage A is appropriately in contact with the heat detection element 6 disposed closer to the protective cover 20 than the sensor body 1 is. Configuration is adopted. That is, the pair of fins 30 that form the inter-fin passage portion 30 </ b> A are formed so as to protrude from the front surface 1 a of the sensor body 1 toward the protective cover 20, and the rear surfaces of the pair of fins 30 and the protective cover 20. A gap 30B is formed between 20a and 20a.
By providing such a pair of fins 30, the high-speed air flow generated in the inter-fin passage portion 30 </ b> A is more protected than the front surface 1 a side of the sensor body 1 due to the influence of the air flow passing through the gap 30 </ b> B. The cover 20 can be biased to a position close to the rear surface 20a side. Therefore, this high-speed airflow can be satisfactorily brought into contact with the heat detection element 6 provided at a position close to the rear surface 20a of the protective cover 20.

  The protective cover 20 which is a wall portion defining the air passage A is formed with an open hole 20b that opens the front side of the heat detection element 6 and the front side of the inter-fin passage portion 30A. The opening hole 20b is an opening hole that opens the installation site of the heat detection element 6 and the inter-fin passage portion 30A to the outside in the protective cover 20 that defines the air passage A. The open hole 20b is formed in an elongated hole shape that is longer in the vertical direction than in the width direction, has a width slightly larger than the diameter of the heat detection element 6, and is provided with the inter-fin passage portion 30A in the vertical direction. The length extends from a position slightly below the position to a position slightly above the position where the heat detection element 6 is installed.

When the heat sensor 100 is attached to the ceiling surface or attached to the diagonally downward wall W with the front surface 1a facing obliquely downward as shown in FIG. When the flow F is generated, the upward flow F of high-temperature air generated around the flow F flows into the heat detection element 6 in the air passage A and the inter-fin passage portion 30 </ b> A through the opening hole 20 b formed in the protective cover 20. At that time, particularly in the attachment state shown in FIG. 3, the open hole 20b that opens the air passage A to the periphery extends from the front side of the heat detection element 6 toward the front side of the inter-fin passage portion 30A on the lower side. By being formed in the shape of the existing long hole, the upward flow F of the surrounding high-temperature air is likely to flow into the air passage A through the open hole 20b while rising.
Then, the air flowing into the air passage A through the open hole 20b can be positively and satisfactorily brought into contact with the heat detection element 6 facing the upper side of the open hole 20b.

  Further, in the air passage A, as shown in FIGS. 4B and 4C, a gap 30B is formed between the pair of fins 30 and the rear surface 20a of the protective cover 20, so that the air passage A The pressure rise on the upstream side of the pair of fins 30 is suppressed. Therefore, the air flowing through the upstream side of the pair of fins 30 in the air passage A is suppressed from flowing out to the surroundings via the lower end portion of the open hole 20b located on the front side, and as a result, the heat detection element More air can be brought into contact with 6.

The front surface 1a of the sensor body 1 is provided with a raised portion 1B that protrudes forward for the purpose of, for example, expanding the electronic component installation area inside the sensor body 1. As shown in FIG. 4A, the raised portions 1 </ b> B are disposed on both the left and right sides of the front surface 1 a of the sensor body 1. Specifically, each of the left and right raised portions 1B has a trapezoidal cross section when viewed from the bottom, as shown in FIG. 4C, and the entire air passage A as shown in FIG. 4B. It is comprised as what extends in an up-down direction over. The front surface of the raised portion 1B is formed as a surface that is spaced apart and opposed to the rear surface 20a of the protective cover 20, and the side wall portions 22 and the fins 30 are provided on the front side of the raised portion 1B. Is provided. Further, in the region between the left and right raised portions 1B, a concave portion 1C extending in the vertical direction is formed, and the heat detecting element 6 is disposed in the concave portion 1C.
Therefore, the air flow generated in the inter-fin passage portion 30A is reliably maintained in the concave portion 1C provided in the region between the left and right raised portions 1B, and is suitable for the heat detection element 6 provided in the concave portion 1C. Can be contacted.

[Another embodiment]
Another embodiment of the present invention will be described. Note that the configuration of each embodiment described below is not limited to being applied alone, but may be applied in combination with the configuration of another embodiment.
(1) In the above embodiment, the pair of fins 30 are formed so as to protrude from the front surface 1a of the sensor body 1 toward the protective cover 20 so as to provide a gap 30B between the rear surface 20a of the protective cover 20. The pair of fins 30 only need to extend inward from the inner surface sides of the left and right side wall portions 22 in the air passage A and form an inter-fin passage portion 30A as a constriction portion therebetween. The shape and arrangement state of the fins 30 such as the height can be modified as appropriate.
For example, as shown in FIG. 5, the pair of fins 30 forming the inter-fin passage portion 30 </ b> A between the front surface 1 a of the sensor body 1 and the protective cover 20 can be formed without forming the gap as described above. It may be provided so as to extend between the rear surface 20a.
Further, as shown in FIG. 6, a pair of fins 30 are formed so as to protrude from the rear surface 20a of the protective cover 20 toward the sensor body 1 so as to provide a gap 30B between the front surface 1a of the sensor body 1. It doesn't matter.

(2) Although the raised portion 1B is provided on the front surface 1a of the sensor body 1 in the above embodiment, the shape and the arrangement state of the raised portion 1B can be appropriately modified.
For example, as shown in FIG. 7, the raised portion may not be provided on the front surface 1 a of the sensor body 1, and the side wall portions 22 and the fins 30 may be provided on the front surface 1 a. In this case, the flow path cross-sectional area of the air passage A between the front surface 1a of the sensor body 1 and the rear surface 20a of the protective cover 20 can be enlarged. This makes it easier for air to flow into the air passage A from the surroundings via the air inlet Ai, and the amount of air that contacts the heat detection element 6 can be further increased.

(3) In the above embodiment, as shown in FIG. 2 and FIG. 3, the example in which the heat sensor 100 is attached to the wall surface W horizontally or obliquely downward has been described, but the heat sensor 100 is installed on the ceiling surface. You can also. Further, even when the heat sensor 100 is installed on the ceiling surface and the front surface 1a of the sensor body 1 is in a downward posture, an upward flow of high-temperature air generated in the surroundings in the event of a fire, The air can be introduced into the air passage A through the open hole 20 b formed in the protective cover 20 and brought into contact with the heat detection element 6.

(4) In the above embodiment, the inter-fin passage portion 30 </ b> A as the constricted portion formed between the pair of fins 30 and the heat detection element 6 provided immediately downstream thereof are arranged in the transverse direction of the air passage A. However, it is sufficient that the heat detection element 6 is located immediately downstream of the inter-fin passage portion 30A, and the installation positions of the heat detection elements 6 in the inter-fin passage portion 30A are as follows. You may change suitably.

(5) In the above embodiment, the protective cover 20 has an opening hole that opens the front side of each of the installation positions of the heat detection element 6 installation position and the inter-fin passage portion 30A formed between the pair of fins 30 to the outside. Although 20b is formed, the shape and position of the open hole 20b may be appropriately modified. Further, when it is not necessary to allow air to flow into the air passage A through the open hole 20b, the open hole 20b may be omitted.

DESCRIPTION OF SYMBOLS 1 Sensor main body 1B Raised part 1a Front surface of sensor main body 6 Heat detection element 20 Protective cover (wall part which defines air passage)
20a Protective cover rear surface 20b Open hole 22 Side wall 22a Side wall inner surface 30 Fin 30A Inter-fin passage (throttle portion)
30B Clearance 100 Heat sensor A Air passage Ai Air inlet Ao Air outlet

Claims (3)

A heat detector having a heat detection element in an air passage extending from an air inlet on one end side to an air outlet on the other end side,
A throttle portion that squeezes the cross-sectional area of the flow path in the air passage and allows air to flow;
The heat detection element is provided in a region immediately downstream of the throttle portion;
A heat detector in which an opening hole is formed in a wall portion defining the air passage to open an installation site of the heat detection element and the throttle portion.   The heat detector according to claim 1, wherein the throttle portion and the heat detection element are provided at a substantially central portion in a transverse direction of the air passage. A protective cover is provided on the front surface of the sensor main body so as to cover the front of the thermal detection element provided so as to protrude from the front surface, as a wall portion defining the air passage, and the front surface of the sensor main body and the protection The space inside the protective cover between the rear surface of the cover is defined by the inner surfaces of the left and right side walls extending from the left and right sides to extend from the lower air inlet to the upper air outlet. And is formed as the air passage extending in the vertical direction,
The heat sensor according to claim 1, wherein the opening hole is formed in the protective cover.

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