JP2020166549A - Heat detector - Google Patents

Abstract

To provide a heat detector that can be easily mounted on a circuit board while pointing the heat detector in an appropriate mounting direction.SOLUTION: In a fire alarm 1, a heat detecting portion 5 is comprised of: a lead portion 5b attached to a circuit board 4 in a state of being inclined and extending linearly from the circuit board 4 toward a cover side; and a heat-sensitive portion 5a provided on a tip side of the lead portion 5b and arranged at a predetermined arrangement position; in which the circuit board 4 is provided with an element mounting portion 40 having a shape that guides a mounting direction of the heat detecting portion 5 on an outer edge portion thereof.SELECTED DRAWING: Figure 1

Description

The present invention relates to a heat detector for fire alarm.

Conventionally, for example, a heat detector in an automatic fire alarm system (hereinafter, also simply referred to as a “heat detector”), a heat detection type residential fire alarm (hereinafter, also simply referred to as a “fire alarm”), etc. As a heat detector is used.

Both heat detectors and fire alarms of this type have a heat detector that has a heat sensitive unit, and when a fire breaks out, the heat of the hot airflow generated by the fire is heat sensitive. It is transmitted to the unit and detects a fire when the output value of the heat detection unit exceeds a certain value. After a fire is detected, in the case of a heat detector, a fire signal is output to the receiver to notify the occurrence of a fire, and in the case of a fire alarm, audio is output from a sound output means such as a speaker provided in the device itself. A fire alarm is issued by the buzzer sound. In both the heat detector and the fire alarm, the heat detector is attached to the circuit board provided in the main body and is provided so as to project outward from the cover covering the main body to create a space around the heat detector. A heat sensitive portion at the tip is arranged on the outside of the cover in order to provide the heat sensor so that heat can be received with high efficiency (see, for example, Patent Document 1 as an example of a heat detector. As an example of a fire alarm, for example, Patent Document. See 2.).

Japanese Patent Application Laid-Open No. 8-287374 Japanese Unexamined Patent Publication No. 2015-141568

In such a heat detector, as the heat detection unit, a lead type heat detection element (thermistor or the like) having a heat sensitive part at the tip of the lead part is generally used. The lead type heat detection element is attached to the circuit board, but in the case of the commonly used lead type heat detection element, the lead part is often long, so the lead part is perpendicular to the circuit board. In many cases, the height position of the heat-sensitive part becomes high. Even if the lead portion is long, the height position of the heat sensitive portion can be lowered if it can be attached to the circuit board in an inclined state. When the heat-sensitive part is exposed from the front cover of the housing, it is necessary to provide a protector on the front cover to protect the heat-sensitive part. However, if the height position of the heat-sensitive part can be lowered, the height of the protector should be increased. It can be lowered and the thickness of the device can be reduced. Further, when the heat sensitive portion is positioned inside the front cover of the housing and is not exposed from the front cover, it is not necessary to provide the protector on the front cover, and of course, the thickness of the device can be reduced.

That is, when a lead type heat detection element is used as the heat detection unit, the heat detection element can be attached to the circuit board in an inclined state regardless of whether the heat sensitive part is exposed from the front cover of the housing or not. If so, the thickness of the device can be reduced.

However, when the lead type heat detection element is to be mounted on the circuit board in an inclined state, there is a problem that it is not easy to mount the lead type heat detection element on the circuit board while directing it in the correct mounting direction during assembly.

In view of the above circumstances, it is an object of the present invention to provide a heat detector that can be easily mounted on a circuit board while pointing the heat detection unit in the correct mounting direction.

The present invention is a heat detector including a main body, a cover attached to the main body, a circuit board, and a heat detection unit attached to the circuit board, wherein the heat detection unit is described from the circuit board to the heat detection unit. It has a lead portion attached to the circuit board in a state of being inclined toward the cover side and extending linearly, and a heat-sensitive portion provided on the tip end side of the lead portion and arranged at a predetermined arrangement position. The circuit board is a heat detector characterized in that an element mounting portion having a shape that guides the mounting direction of the heat detecting portion is provided on the outer edge portion thereof.

In the present invention, the element mounting portion of the circuit board is a notch into which the base end side of the lead portion of the heat detecting portion is inserted and mounted, and a predetermined heat sensitive portion of the heat detecting portion is formed from the element mounting portion. It may have a notch that opens in a direction along the plan view in the direction toward the arrangement position. Further, the notch of the element mounting portion may extend from the element mounting portion in a direction along a plan view in a direction toward a predetermined arrangement position of the heat sensitive portion of the heat detection unit.

Further, in the present invention, in the circuit board, the outer edge portion provided with the element mounting portion is orthogonal to the direction from the element mounting portion toward a predetermined arrangement position of the heat sensitive portion of the heat detection unit in a plan view. It can be formed and provided.

Further, in the present invention, the element mounting portions of the circuit board are provided on the outer edges of the circuit boards on opposite sides to each other, and the heat detection portions are mounted on each of the element mounting portions, and at least. Two of them can be provided with their respective heat-sensitive portions located on the outer peripheral side.

Further, in the present invention, a first predetermined arrangement position and a second predetermined arrangement position in which the distances from the center of the detector are different from each other are set as the predetermined arrangement positions of the heat sensitive part of the heat detection unit. The element mounting portion of the circuit board has a shape that guides the mounting direction of the heat detecting portion toward the first predetermined placement position of the heat sensitive portion. It has a portion and a second element mounting portion having a shape that guides the mounting direction of the heat detecting portion toward the placement position corresponding to the second predetermined placement position of the heat sensitive portion. can do.

In the present invention, the heat detection unit can be mounted on the circuit board according to the mounting direction guided by the element mounting portion.

Therefore, according to the present invention, the heat detection unit can be easily mounted on the circuit board while being oriented in the correct mounting direction.

An example of the embodiment of the present invention is shown, and is a top view of a fire alarm with the cover open. It is sectional drawing of the fire alarm of the same above. In the drawing, the cover side is shown on the top and the base side is shown on the bottom. For example, when the cover side is installed on the ceiling surface, the top and bottom are reversed. It is the top view of only the circuit board in the fire alarm of the same above. It is explanatory drawing which superposed the fire alarm of the same above with different outer diameters.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings as an example of application to a heat detection type residential fire alarm. However, the present invention is not limited to such fire alarms, and can be applied to other heat detectors such as heat detectors in automatic fire alarm equipment. In the following description, terms indicating a position or direction such as "upper" or "lower" are used according to the position or direction on the drawing (FIG. 2).

First, the fire alarm 1 according to the embodiment of the present invention will be described with reference to FIGS. 1 to 3.

-Overall configuration As shown in FIGS. 1 and 2, the fire alarm 1 includes a main body 2, a cover 3 attached to the main body 2, a circuit board 4, and a heat detection unit 5 attached to the circuit board 4. Be prepared. The fire alarm 1 further includes a base 6 for mounting. Although not shown, the base 6 is fixed to the installation surface such as the ceiling surface by screwing or the like, the main body 2 is attached to the base 6, and the fire alarm 1 is attached to the installation surface such as the ceiling surface. It is to be installed.

-Main body The main body 2 has a disc-shaped middle plate 2a. The circuit board 4 is supported and provided on the middle plate 2a thereof. In addition, various parts such as a speaker 7 and a battery storage portion 8 are further provided on the middle plate 2a.

-Cover The cover 3 has a disk-shaped upper surface portion 3a and a tubular peripheral surface portion 3b continuous with the peripheral edge thereof, and has a covered cylindrical shape. The cover 3 is attached to the main body 2 and forms a housing in which various parts such as a circuit board 4, a speaker 7, and a battery housing 8 are incorporated together with the main body 2.

The upper surface portion 3a is provided with a vertical hole 3f formed as a through hole in the vertical direction at a position on the outer peripheral side. The vertical holes 3f correspond to the heat detection unit 5 described later, and in the case of the present embodiment, the vertical holes 3f are provided at two locations on the outer peripheral side of the detector on opposite sides to the heat detection unit 5. .. Further, the peripheral surface portion 3b is provided with a slit 3d formed as a through hole in the horizontal direction while forming a slit shape in the circumferential direction at a position corresponding to the internal space above the circuit board 4. Both the vertical holes 3f and the slits 3d function as a distribution unit for hot air flow in the event of a fire.

-Heat detection unit The heat detection unit 5 is a heat detection element having a lead unit 5b and a heat sensitive unit 5a provided on the tip side thereof. In the heat detection unit 5, the lead unit 5b is attached to the circuit board 4 in a state of being inclined and linearly extending from the circuit board 4 toward the cover 3. The heat sensitive portion 5a is located on the tip end side of the lead portion 5b, and is arranged at a predetermined arrangement position P in the fire alarm 1. When arranged at the predetermined arrangement position P, the heat-sensitive portion 5a is located directly below the vertical hole 3f in the case of the present embodiment. As the heat detection unit 5, for example, a heat detection element such as a lead type thermistor is used.

In the present embodiment, two heat detection units 5 are provided, and the respective heat sensing units 5a are provided at positions on the outer peripheral side of the detector on opposite sides (symmetrical positions in a plan view in the illustrated example). The predetermined arrangement positions P of the heat sensitive unit 5a are also set at two locations, which are located on the outer peripheral side of the detector on opposite sides to each other. The number of the heat detection units 5 may be one or more, and the arrangement thereof is not limited to the outer peripheral side and may be at another position such as the central portion.

Further, the heat detection unit 5 specifically has a substantially triangular mounting base portion 5c on the base end side of the lead portion 5b. A heat-sensitive portion 5a is provided on the tip end side of a portion that extends linearly from the apex portion of the mounting base portion 5c to the tip end side. A mounting pin 5d is provided so as to be linearly exposed on the base end side from the wide bottom portion 5cc of the mounting base portion 5c. The bottom portion 5cc of the mounting base portion 5c is provided substantially perpendicular to the linear portion of the lead portion 5b, and the mounting pin 5d is provided substantially parallel to the linear portion in the plan view. Here, in the heat detection unit 5, the bottom portion 5cc and the mounting pin 5d of the mounting base 5c will be described later, but when the heat detection unit 5 is mounted on the circuit board 4, the mounting direction on the heat detection unit 5 side. It functions as a shape part that guides.

Here, the heat sensitive portion 5a is located inside the cover 3 as described above. Therefore, it is not necessary to project the protector from the upper surface portion 3a of the cover 3 to the outside (front side), and the upper surface portion 3a of the cover 3 can be made flat. As a result, the fire alarm 1 can be made thinner. The heat sensitive portion 5a may be exposed to the outside of the cover 3. In that case, it is necessary to provide a protector that protects the heat-sensitive portion 5a, but if the height position of the heat-sensitive portion 5a is lowered, the height of the protector can be lowered and the device can be made thinner.

-Circuit board The circuit board 4 has a flat plate shape, is arranged horizontally, and is supported and provided on the middle plate 2a of the main body 2 as described above. Then, the circuit board 4 is provided with an element mounting portion 40 to which the heat detecting portion 5 is mounted on the outer edge thereof.

-Element mounting portion The element mounting portion 40 has a shape that guides the mounting direction of the heat detection unit 5. The element mounting portion 40 allows the heat detecting portion 5 to be easily mounted on the circuit board 4 while being oriented in the correct mounting direction. As described above, the fire alarm 1 is set at two predetermined arrangement positions P of the heat sensitive unit 5a of the heat detection unit 5 on the outer peripheral side of the detector on opposite sides to each other. Correspondingly, the element mounting portions 40 are also provided at two locations.

Here, in the case of the present embodiment, the element mounting portion 40 is assumed to have a first element mounting portion 41 and a second element mounting portion 42. The first element mounting portion 41 corresponds to a predetermined arrangement position P of the heat sensitive portion 5a of the heat detecting portion 5 in the fire alarm 1. First, the first element mounting portion 41 will be described in detail, and the second element mounting portion 42 will be described in detail later. The element mounting portion 40 provided on the circuit board 4 may be only the first element mounting portion 41.

First element mounting part The first element mounting part 41 corresponds to a predetermined arrangement position P of the heat sensitive part 5a of the heat detecting part 5 in the fire alarm 1, and guides the mounting method of the heat detecting part 5. It has a notch 41a as a shape portion to be formed.

-Notch portion The notch portion 41a functions as a heat detection unit 5 to which the heat detection unit 5 is attached by inserting the attachment pin 5d on the base end side of the heat detection unit 5, and guides the attachment direction of the heat detection unit 5. For this purpose, the heat sensitive unit 5a of the heat detection unit 5 is opened in a direction toward a predetermined arrangement position P in a plan view (see FIG. 3). Since the mounting portion of the mounting pin 5d of the heat detection unit 5 is a notch portion 41a (including the case where the heat detection unit 5 is formed as a pore), the mounting pin 5d is bent even when the heat detection unit 5 is mounted with an inclination. Can be inserted and installed without.

Here, consider a case where a circular through hole is formed in the circuit board instead of the notch portion 41a. In this case, the lead portion cannot be tilted unless the mounting pin of the heat detection unit is bent, and in order to tilt the lead portion and mount it on the board without bending the mounting pin, is it necessary to make the through-hole hole considerably large? , Must have a special shape such as an oval. Therefore, the present embodiment in which the notch is provided in the exterior portion of the circuit board is excellent as a method for mounting the heat detection portion at an angle with respect to the substrate.

When attaching the heat detection unit 5, the direction of the opening of the notch 41a is used as a guide, and the direction of the lead portion 5b of the heat detection unit 5 is attached along the direction of the opening of the notch 41a in a plan view. By doing so, the heat sensitive portion 5a can be directed to the predetermined arrangement position P in a plan view.

Further, the cutout portion 41a is cut in a direction in a plan view in a direction toward a predetermined arrangement position P as well as a cut direction from the outer edge. That is, even if the notch direction from the outer edge of the notch portion 41a is used as a guide, the heat sensitive portion 5a can be directed to the predetermined arrangement position P in a plan view. The cutout portion 41a may be cut longer so as to extend in the direction along the predetermined arrangement position P in a plan view, or may be a pore instead of the notch. ..

Here, the heat detection unit 5 is attached by soldering the attachment pin 5d to the notch 41a, etc., but the attachment pin 5d is parallel to the direction of the lead portion 5b in a plan view as described above. By aligning the direction of the mounting pin 5d with the direction of the notch portion 41a, the heat sensitive portion 5a can be directed to the predetermined arrangement position P in a plan view.

-Mounting edge portion The first element mounting portion 41 further has a mounting edge portion 41b as a shaped portion that guides the mounting method of the heat detection unit 5. The mounting edge portion 41b is a portion in which the notch portion 41a is formed, but is formed in a direction orthogonal to the direction along the plan view in the direction toward the predetermined arrangement position P of the heat sensitive portion 5a of the heat detection unit 5. (See FIG. 3). Notches 41a are provided at both ends of the mounting edge 41b.

As described above, the bottom portion 5cc of the mounting base portion 5c of the heat detection portion 5 is provided at a substantially right angle to the direction of the lead portion 5b. That is, the heat-sensitive portion 5a can be directed to the predetermined arrangement position P in a plan view by aligning the direction of the bottom portion 5cc with the direction of the mounting edge portion 41b.

The vertical edge portion first element mounting portion 41 further has a vertical edge portion 41c as a shape portion that guides the mounting method of the heat detection unit 5 (see FIG. 3). The vertical edge portion 41c is provided so as to be continuous with the mounting edge portion 41b and substantially perpendicular to the mounting edge portion 41b, that is, formed in a direction along the predetermined arrangement position P in a plan view. Provided. That is, even if the vertical edge portion 41c is used as a guide, the heat sensitive portion 5a can be directed to the predetermined arrangement position P in a plan view.

-Second element mounting portion In the case of this embodiment, the element mounting portion 40 further has a second element mounting portion 42 at a position different from that of the first element mounting portion 41. Like the first element mounting portion 41, the second element mounting portion 42 also has a notch portion 42a and a mounting edge portion 42b, but they are provided at an angle different from that in the first element mounting portion 41. (See FIG. 3), the first element mounting portion 41 corresponds to a predetermined arrangement position P corresponding to a different arrangement position from the center of the alarm, and the outer diameter is different from that of the fire alarm 1. It corresponds to a fire alarm.

In FIG. 4, a fire alarm 1 and a fire alarm 1'with a larger outer diameter are overlapped on both the first element mounting portion 41 and the second element mounting portion 42 while aligning their centers with each other. It is explanatory drawing which showed the state which the heat detection part 5 is attached.

As shown in the figure, the outer diameter D'of the fire alarm 1'is larger than the outer diameter D of the fire alarm 1. Therefore, the distance from the center of the alarm is set longer in the predetermined arrangement position P'of the fire alarm 1'than in the predetermined arrangement position P of the fire alarm 1. The first element mounting portion 41 corresponds to the predetermined arrangement position P of the fire alarm 1, and the second element mounting portion 42 corresponds to the predetermined arrangement position P'of the fire alarm 1'. The same heat detection unit 5 is attached to the first element attachment portion 41 and the second element attachment portion 42, but the heat sensitive portion 5a on the side attached to the first element attachment portion 41 is a fire alarm 1. The heat-sensitive portion 5a on the side to be attached to the second element attachment portion 42 is correctly positioned at the predetermined arrangement position P'of the fire alarm 1'.

That is, since the circuit board 4 has the first element mounting portion 41 and the second element mounting portion 42, the same heat detection unit 5 as the same circuit board 4 is used, but from the center of the alarm. It is possible to correspond to both a predetermined arrangement position P (first predetermined arrangement position) and an arrangement position P'(second predetermined arrangement position), which are set as different distances. , It is possible to correspond to both the fire alarm 1 and the fire alarm 1'with different outer diameters. In either case, the heat-sensitive unit 5a of the heat detection unit 5 can be correctly positioned at a predetermined arrangement position P or arrangement position P'.

The second element mounting portion 42 corresponding to the fire alarm 1'(the side having the larger outer diameter of the housing) is provided on the center line side in the longitudinal direction of the circuit board 4. The angle of the notch 42a in the second element mounting portion 42 (angle in the mounting direction in a plan view) is set so that the heat sensitive portion 5a of the heat detecting element 5 is located at a predetermined arrangement position P'. .. On the other hand, the first element mounting portion 41 corresponding to the fire alarm 1 (the side having the smaller outer diameter of the housing) is separated from the center line in the longitudinal direction of the circuit board 4 than the second element mounting portion 42. It is provided at the position. Then, the angle (same as above) of the notch portion 41a in the first element mounting portion 41 is set so that the heat sensitive portion 5a of the heat detection element 5 is located at a predetermined arrangement position P. That is, the angle of the notch portion 41a in the first element mounting portion 41 is different from the angle of the notch portion 42a in the second element mounting portion 42. Specifically, the angle of the notch portion 41a is set so that the heat-sensitive portion 5a of the heat detection element 5 attached to the element attachment portion 41 is located closer to the center side of the housing. Therefore, even if heat detection elements having the same lead portion length are used for the heat detection unit 5, two types of outer diameter housings (for example, the fire alarm 1 and the same) can be used by changing the mounting position on the circuit board 4. It is possible to correspond to 1').

[Changes in embodiments, etc.]
Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications and the like can be made within the scope of the gist of the invention.

For example, with respect to the first element mounting portion 41 and the second element mounting portion 42, in the illustrated example, the predetermined placement position P and the placement position P'are located on a straight line passing through the center of the detector. It may not be located on a straight line passing through the center of the detector. The reason why P and P'are arranged on a straight line passing through the center of the detector is to enable the heat flow from any direction to be received without delay. That is, if P and P'are arranged on a straight line that does not pass through the center of the housing, heat can be quickly received from a hot air flow from a specific direction, but hot air from a direction 180 degrees opposite to the specific direction. The heat receiving effect is reduced with respect to the flow.

Further, although the mounting edge portion 41b is oriented orthogonal to the direction toward the predetermined arrangement position P, it may be at any angle.

1, 1': Fire alarm 2: Main body 3: Cover 3a: Top surface 3b: Peripheral surface 3d: Slit 3f: Vertical hole 4: Circuit board 40: Element mounting part 41: First element mounting part 41a: Notch Part 41b: Mounting edge 41c: Vertical edge 42: Second element mounting 42a: Notch 42b: Mounting edge 5: Heat detection 5a: Heat sensitive 5b: Lead 5c: Mounting base 5cc: Bottom 5d: Mounting pin 6: Base 7: Speaker 8: Battery storage P: Predetermined placement position P': Predetermined placement position

Claims (5)

A heat detector including a main body, a cover attached to the main body, a circuit board, and a heat detection unit attached to the circuit board.
The heat detection unit is provided at a lead portion attached to the circuit board in a state of being inclined and linearly extending from the circuit board toward the cover side, and at a predetermined arrangement position provided on the tip end side of the lead portion. It has a heat-sensitive part to be arranged,
The circuit board is a heat detector characterized in that an element mounting portion having a shape for guiding the mounting direction of the heat detecting portion is provided on the outer edge portion thereof. The element mounting portion of the circuit board is a notch into which the base end side of the lead portion of the heat detecting portion is inserted and mounted, and faces a predetermined arrangement position of the heat sensitive portion of the heat detecting portion from the element mounting portion. The heat detector according to claim 1, further comprising a notch that opens in a direction along the plan view. The second aspect of the present invention, wherein the notch of the element mounting portion extends from the element mounting portion in a direction along a plan view in a direction toward a predetermined arrangement position of the heat sensitive portion of the heat detecting portion. Heat detector. The circuit board is provided so that the outer edge portion on which the element mounting portion is provided is formed in a direction orthogonal to the predetermined arrangement position of the heat sensitive portion of the heat detecting portion in a plan view from the element mounting portion. The heat detector according to any one of claims 1 to 3. As the predetermined arrangement position of the heat sensitive part of the heat detection unit, a first predetermined arrangement position and a second predetermined arrangement position in which the distances from the center of the detector are different from each other are set.
The element mounting portion of the circuit board has a shape corresponding to a first predetermined arrangement position of the heat sensitive portion and guides the mounting direction of the heat detection portion toward the arrangement position. It is characterized by having a second element mounting portion having a shape that guides the mounting direction of the heat detecting portion toward the placement position corresponding to the second predetermined placement position of the heat sensitive portion. The heat detector according to any one of claims 1 to 4.

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