JP2014170495A - Sensor adapter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sensor adapter which can be attached to a fire sensor and an existing sensor base and has a terminating function and allows easy modification or addition of functions.SOLUTION: A sensor adapter 40 is provided between a sensor base 50 which is attached to an installation surface 30 and to which a sensor line 3 extending from a fire receiver 1 is connected, and a fire sensor 20, and is connected to the fire sensor 20 and the sensor base 50 via a conductive terminal part 42A. The sensor adapter 40 includes an adapter body 40A and a circuit board 70 detachably attached to the adapter body 40, and the adapter body 40A includes a board housing part 44A more deeply recessed than a height of the circuit board 70 to house the circuit board 70 and locking means 43A provided in the terminal part 42A to lock the circuit board 70.

Description

  The present invention relates to a sensor adapter on which a circuit board having a termination function is mounted.

For example, in a conventional fire alarm system, a fire receiver is installed in the central monitoring room, a line line and a common line are provided from the fire receiver as a detector line, and the line line and the common line are terminated resistors. Some are connected via a cable (for example, see Patent Document 1).
Such a fire receiver is called a P-type fire receiver, and judges a fire or the like by comparing the voltage between the line line and the common line with each threshold value such as a fire threshold value and a disconnection threshold value.

In the fire alarm system described in Patent Document 1, abnormalities in the wiring of the sensor line can be determined, but when a fault (abnormality) occurs in the fire detector, the fire receiver displays a voice or indication of the fault in the fire detector. Etc. could not be notified.
In order to notify the fire receiver that a failure has occurred in the fire detector, use a fire detector with a self-inspection function that outputs a signal such as a pulse to the fire receiver when a failure has occurred in the fire detector. At the same time, there is a problem in that it must be replaced with a dedicated fire receiver (for example, R type) that communicates with the fire detector.

In view of this, there is considered a fire alarm facility that can notify a malfunction occurring in a fire detector without replacing an existing fire receiver without using a dedicated fire receiver, and a fire detector used therefor.
In this case, the fire sensor connected to the end of the sensor line receives a signal from the fire sensor via the sensor line, and when the abnormal signal is received, the terminal resistor is connected to the sensor line. It is conceivable to add a function for intermittent disconnection. By adding this function, even if it is not a dedicated fire receiver, the existing fire receiver can notify the malfunction of the fire detector, whether the wiring of the sensor line is broken, or the malfunction of the fire detector Can be determined by the fire receiver.

Therefore, the fire sensor connected to the end of the sensor line receives a signal from the fire sensor via the sensor line and intermittently connects the terminal resistor to the sensor line when an abnormal signal is received. It is necessary to mount a function to be disconnected (hereinafter referred to as a termination function).
Conventionally, when a specific function is added to the fire detector, a sensor adapter having the function is attached between the fire detector and the sensor base (for example, see Patent Document 2).

JP-A-6-176289 JP-A-5-325061

Since the sensor adapter described in Patent Document 2 is dedicated to the function, even if it is necessary to change to another function or add a function, the function is changed or added. There was a problem that scalability was poor because it was not possible.
In addition, it is possible to recreate a sensor adapter corresponding to the function, but there is a problem that it is costly and is not economical.

  The present invention has been made to solve the above-described problems, and is equipped with a circuit board that can be attached to a fire sensor and an existing sensor base and has a termination function. An object of the present invention is to provide a sensor adapter that allows easy addition of functions.

  A sensor adapter according to the present invention is provided between a fire sensor and a sensor base that is attached to an installation surface and connected to a sensor line extending from a fire receiver, and has a conductive terminal. An adapter for a sensor connected to a fire sensor and a sensor base via a section, comprising: an adapter body; and a circuit board detachably provided on the adapter body, wherein the adapter body houses the circuit board For this purpose, the circuit board has a board housing part that is recessed deeper than the height of the circuit board, and a locking means that is provided in the terminal part and locks the circuit board.

  The sensor adapter according to the present invention can be attached to a fire sensor and an existing sensor base and is equipped with a circuit board having a termination function, so that it is easy to change the function or add a function. Excellent expandability and economy.

It is an example of outline composition of fire alarm equipment with which a circuit board carried in a sensor adapter concerning Embodiment 1 of the present invention was connected. It is an example of the structure of the control circuit which implement | achieves the termination | terminus function mounted in the circuit board mounted in the adapter for sensors which concerns on Embodiment 1 of this invention. It is a side view at the time of attaching the adapter for sensors which concerns on Embodiment 1 of this invention between a fire sensor and the existing sensor base. FIG. 4 is a front view of the sensor base shown in FIG. 3. It is the front view and back view of an adapter main body of the adapter for sensors which concern on Embodiment 1 of this invention. FIG. 3 is a front perspective view of a circuit board on which the control circuit shown in FIG. 2 is mounted. It is a front perspective view of the adapter cover of the sensor adapter according to Embodiment 1 of the present invention. FIG. 7 is a front perspective view when the circuit board shown in FIG. 6 is mounted on the sensor adapter according to the first embodiment of the present invention. It is a front perspective view of the adapter cover of the sensor adapter according to Embodiment 2 of the present invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The present invention is not limited to the embodiments described below. Moreover, in the following drawings, the relationship of the size of each component may be different from the actual one.
Embodiment 1 FIG.
FIG. 1 is a schematic configuration example diagram of a fire alarm system 100 to which a circuit board 70 mounted on a sensor adapter 40 according to Embodiment 1 of the present invention is connected. In FIG. 1, three fire detectors 20 are provided, and the terminating resistor 15 mounted on the sensor adapter 40 is mounted on the sensor line 3 at the fire sensor 20 at the end of the sensor line 3. And a circuit board 70 having a termination function is connected. The circuit board 70 is connected to the end of the sensor line 3 with respect to the fire receiver 1, and the terminal line 15 is connected to the end of the sensor line 3 by connecting a terminal resistor 15 to the sensor line 3 in a normal state. The fire receiver 1 is informed that there is no disconnection in the middle and that there is no abnormality in the fire detector 20. Here, in the first embodiment, the number of fire detectors 20 is three, but is not limited thereto.

The fire alarm system 100 can notify the malfunction that has occurred in each of the fire detectors 20, and can detect the malfunction of the fire detector 20 in the fire receiver 1 by alarming the malfunction with the fire receiver 1. It is a thing.
The fire alarm system 100 includes a fire detector 20 installed in each room of a building (for example, a hotel, an apartment house such as a condominium, an office building, a commercial facility, etc.) and an alarm based on the detection result of the fire detector 20. The P-type fire receiver 1 is connected by a common line 3A and a line line 3B which are sensor lines 3. The P-type fire receiver means that the electrical contact of the fire sensor 20 connected to the sensor line 3 composed of the common line 3A and the line line 3B is closed, thereby causing an electrical change in the sensor line 3. The fire is judged based on this.
Further, the P-type receiver passes a minute current through the sensor line 3 via the termination resistor 15, and determines the disconnection of the sensor line 3 when the minute current due to the termination resistor 15 stops flowing.
Hereinafter, the common line 3A and the line line 3B are collectively referred to as a sensor line 3.

FIG. 2 is an example of the configuration of the control circuit 10 that realizes the termination function mounted on the circuit board 70 mounted on the sensor adapter 40 according to Embodiment 1 of the present invention.
A circuit board 70 shown in FIG. 1 is mounted with a control circuit 10 that realizes a termination function. The control circuit 10 includes a receiving circuit 12, a constant voltage circuit 11, a disconnect circuit 14, and a discrimination circuit as shown in FIG. 13 and a termination resistor 15 are provided, and the termination resistor 15 is connected to the disconnection circuit 14 and the sensor line 3.
The receiving circuit 12 monitors the voltage of the sensor line 3. That is, the receiving circuit 12 of the circuit board 70 receives the abnormal signal from the fire detector 20 via the sensor line 3.
The constant voltage circuit 11 supplies a predetermined constant voltage for operation to the receiving circuit 12 or the like.
The disconnect circuit 14 controls the connection between the termination resistor 15 and the sensor line 3 based on the output of the determination circuit 13. That is, when the discrimination circuit 13 discriminates that any of the fire detectors 20 is defective, the discrimination circuit 13 outputs an output corresponding to the discrimination result, and the disconnection circuit 14 that receives the output outputs the sensor circuit 3 and the termination resistor 15. The operation of disconnecting, connecting after a predetermined time elapses, and disconnecting again after a predetermined time elapses is repeated.

  As a result, even the P-type fire receiver 1 can detect an intermittent disconnection of the sensor line 3 as an abnormal signal and can alarm the abnormality intermittently. be able to. That is, since the fire alarm system 100 according to the first embodiment connects the circuit board 70 mounted on the sensor adapter 40 to the end of the sensor line 3, it receives the result of self-inspection of the fire sensor 20. Even in the case of the fire receiver 1 that is not a dedicated fire receiver that can be controlled, the failure of the fire detector 20 can be notified.

FIG. 3 is a side view when the sensor adapter 40 according to the first embodiment of the present invention is attached between the fire sensor 20 and the existing sensor base 50. FIG. 3 illustrates a state in which the sensor base 50 is attached to the ceiling 30, the sensor adapter 40 is then attached to the sensor base 50, and finally the fire sensor 20 is attached to the sensor adapter 40. Yes.
Next, a smoke detector as an example of the fire detector 20 attached to the detector adapter 40 according to the first embodiment will be described.

The fire detector 20 includes a case main body 21 that forms the exterior of the fire detector 20 and a smoke detection unit 25 provided in the case main body 21.
The case body 21 has a circular shape in plan view, and the front surface 22 is provided with a lid portion 24 projecting from the rear surface 27 toward the front surface 22 and between the lid portion 24 and the surface 22 of the case main body 21. And an opening 26 for introducing smoke.
The lid portion 24 is configured integrally with the case main body 21 via the extending portion 23.
Further, four conductive blade fittings (not shown) are provided on the back surface 27 of the case body 21 along the circumferential direction. Although the back surface 27 of the case body 21 is not shown, it is the same as FIG. Further, the blade bracket will be described later.
Here, in the first embodiment, the number of blade fittings is four, but is not limited thereto.

Next, the internal structure of the case body 21 including the smoke detection unit 25 will be described.
The smoke detection unit 25 is configured, for example, in a cylindrical shape, and the entire outer peripheral surface of the side surface portion is configured as an introduction portion for introducing smoke. The outer peripheral surface of the side surface portion is constituted by an insect repellent wire net or the like so that a gas such as smoke can pass and insects do not enter.

  Further, inside the smoke detection unit 25, a light emitting element (not shown) and a light receiving element (not shown) are concentric, and a line segment connecting the center of the concentric circle with each of the light emitting element and the light receiving element is a predetermined number. They are arranged at an angle. The light emitting element and the light receiving element constitute a smoke sensor (not shown) for detecting intruding smoke.

  The smoke detection unit 25 periodically emits light from the light emitting element. When the smoke enters, the smoke detection unit 25 diffuses the light by the smoke particles that have entered, so that the light reaches the light receiving element and outputs the light reception state to the alarm control unit (not shown) as the smoke detection result. . The inside of the smoke detection unit 25 is formed in, for example, a labyrinth, and external light does not enter the smoke detection unit 25 directly or indirectly, so that the external light is received by the light receiving element. It does not affect smoke detection.

FIG. 4 is a front view of the sensor base 50 shown in FIG.
Next, the structure of the sensor base 50 to which the sensor adapter 40 according to the present embodiment is attached will be described.
The sensor base 50 is circular in plan view like the case main body 21 and is provided with four conductive terminal portions 51 and four blade receiving brackets 52 integrally formed with the terminal portions 51 along the circumferential direction. Similarly, two screw insertion holes 53 are formed along the circumferential direction, and a drawing port 54 is formed at the center.
Here, in the first embodiment, the number of the terminal portions 51 and the blade brackets 52 is four, and the number of the screw insertion holes 53 is two, but is not limited thereto.

The screw insertion hole 53 is provided to attach the sensor base 50 to the installation surface (the ceiling 30 in this embodiment) by screwing.
The blade bracket 52 is for attaching the sensor adapter 40 to the sensor base 50 and also for attaching the fire sensor 20 to the sensor base 50.

  The inlet 54 is a hole provided for drawing the sensor line 3 (common line 3A and line 3B) from the outside into the sensor base 50. The inlet 54 is drawn into the sensor base 50 from the inlet 54. The sensor line 3 is connected to the terminal unit 51.

5A is a front view of the adapter main body 40A of the sensor adapter 40 according to the first embodiment of the present invention, and FIG. 5B is an adapter of the sensor adapter 40 according to the first embodiment of the present invention. It is a back view of 40 A of main bodies.
The sensor adapter 40 is composed of an adapter main body 40A and an adapter cover 40B described later. The adapter main body 40A and the adapter cover 40B are both formed of an insulator such as plastic.

The adapter main body 40A is circular in plan view like the case main body 21 and the sensor base 50, and four conductive blade support brackets 41A are provided on the front surface along the circumferential direction. The conductive terminal portions 42A are integrally formed on the two facing each other. A hook 43A (locking means) is provided at the end of the two terminal portions 42A so as to protrude toward the front of the adapter main body 40A (in the direction orthogonal to the plane of FIG. 5A and the front side). .
In addition, a substrate housing portion 44A that is recessed along the shape of the circuit board 70 is provided at the center of the adapter body 40A. The side surface of the substrate housing portion 44A has two opposing locations at the center of the adapter body 40A. A convex portion (first fitting portion) 45A that protrudes toward the top is provided.
The shape of the circuit board 70 will be described later.

Further, four conductive blade fittings 47A are provided along the circumferential direction on the back surface 46A of the adapter main body 40A, and the blade fitting 47A and the blade receiving fitting 41A are electrically connected.
Here, in Embodiment 1, the number of the blade fittings 47A and the blade receiving fittings 52 is four, and the number of the terminal portions 42A, the hooks 43A, and the convex portions 45A is two. However, the present invention is not limited to these. Absent.

Next, how to attach the fire detector 20, the detector adapter 40, and the detector base 50 to the ceiling (installation surface) 30 will be described.
First, as shown in FIG. 3, the back surface of the sensor base 50 is directed to the ceiling 30, and screws are attached to the ceiling 30 through screws through the screw insertion holes 53.
Next, by rotating the blade fitting 47A provided on the back surface 46A of the sensor adapter 40 (adapter body 40A) in accordance with the blade receiving fitting 52 provided on the front surface of the sensor base 50, the blade fitting 47A is The sensor adapter 40 is attached to the sensor base 50 in combination with the blade bracket 52.
Finally, a not-illustrated blade metal fitting provided on the back surface 27 of the fire detector 20 is rotated according to a blade receiving metal fitting 41A provided in front of the sensor adapter 40 (adapter body 40A), thereby omitting the illustration. Are connected to the blade receiving bracket 41A, and the fire detector 20 is attached to the detector adapter 40.

  The sensor line 3 drawn into the sensor base 50 from the lead-in port 54 is connected to the terminal portion 51, but is electrically connected to the blade fitting 47A coupled with the blade receiving fitting 52 formed integrally with the terminal portion 51. To do. Further, since the blade bracket 47A is electrically connected to the blade bracket 41A, the fire detector 20 is electrically connected to the sensor line 3 via a blade bracket (not shown) coupled to the blade bracket 41A.

FIG. 6 is a front perspective view of the circuit board 70 on which the control circuit 10 shown in FIG. 2 is mounted.
The circuit board 70 has a shape in which two opposite end faces having a circular shape in a plan view are cut out so as to be parallel to each other. Two contact portions 72 projecting in the outer circumferential direction are provided at positions different from the notched end surfaces so as to face each other. Moreover, the hole part 71 is provided in the two contact parts 72, and the electrode pattern 73 is each provided around the hole part 71, and the electrode pattern 73 and the control circuit 10 are electrically connected.

FIG. 7 is a front perspective view of the adapter cover 40B of the sensor adapter 40 according to Embodiment 1 of the present invention.
The adapter cover 40B has a shape similar to that of the circuit board 70 in plan view, but is slightly larger than the circuit board 70, and the side surface portion 41B constituting the outer periphery covers the side surface of the circuit board 70. Is provided. Further, four substrate pressing portions 42B are provided from the inside of the side surface portion 41B toward the center of the adapter cover 40B. The height of the board pressing portion 42B is lower by about the thickness of the circuit board 70 than the height of the side face portion 41B. The side surface portion 41B is provided with two concave portions (second fitting portions) 43B at positions corresponding to the convex portions 45A when the adapter cover 40B is attached to the board housing portion 44A of the adapter main body 40A.
Here, in the first embodiment, the number of the substrate pressing portions 42B is four and the number of the concave portions 43B is two, but is not limited thereto. Further, the concave portion 43B may be a hole through which the convex portion 45A is inserted.

FIG. 8 is a front perspective view when the circuit board 70 shown in FIG. 6 is mounted on the sensor adapter 40 according to Embodiment 1 of the present invention.
Next, a method for mounting the circuit board 70 on the sensor adapter 40 will be described.
First, the two hole portions 71 of the circuit board 70 are respectively hooked on the hooks 43A of the adapter main body 40A, and the circuit board 70 is accommodated in the substrate accommodating portion 44A so that the terminal portion 42A and the electrode pattern 73 are in contact with each other. Here, the hook 43 </ b> A has a shape that is slightly smaller than the inner diameter of the hole 71 of the circuit board 70 and protrudes more than the thickness of the circuit board 70. The circuit board 70 is detachable from the adapter main body 40A.
Next, the front surface of the adapter cover 40B is directed to the adapter main body 40A and the circuit board 70, and the adapter cover 40B is pushed into the board housing portion 44A so that the two concave portions 43B are aligned with the convex portions 45A. Are fitted to the adapter main body 40A. At this time, since the board pressing portion 42B presses the circuit board 70, it is possible to suppress the circuit board 70 from moving in the board housing portion 44A. Here, the convex portion 45A and the concave portion 43B are provided at positions orthogonal to a line connecting the two hooks 43A.

  The terminal portion 42A is in contact with the electrode pattern 73, and the terminal portion 42A and the sensor line 3 are electrically connected through the terminal portion 51, the blade bracket 52, the blade bracket 47A, and the blade bracket 41A. The sensor line 3 and the circuit board 70 are electrically connected. Therefore, the circuit board 70 and the fire detector 20 are electrically connected via the terminal portion 42A, the blade bracket 41A, the blade bracket 47A, and the blade bracket of the fire detector 20 (not shown).

As described above, the circuit board 70 having a termination function is mounted on the sensor adapter 40, and the sensor adapter 40 is attached to the fire sensor 20 and the existing sensor base 50, thereby terminating the fire alarm system 100. Functions can be added.
Therefore, even when it is desired to add a termination function to a fire alarm facility having no termination function, the circuit board 70 having a termination function is connected to the fire sensor 20 and the existing sensor base 50 connected to the termination of the sensor line 3. This can be realized by attaching the mounted adapter 40 for the sensor, and it is not necessary to replace it with a dedicated fire sensor or sensor base, thereby reducing the cost.

  In addition, it is necessary to change the function installed in the fire alarm facility 100 to a function other than the termination function, for example, a buzzer function that warns that the fire detector 20 detects a fire, or to add a buzzer function. Even if the circuit board 70 corresponding to that is replaced, it can be realized by replacing only the circuit board 70 corresponding to it with the adapter 40 for the sensor, so that the extensibility is excellent.

  Even if the function is changed or added, the sensor adapter 40 can be used in common, and it is not necessary to recreate the sensor adapter 40. Therefore, the cost can be reduced and the cost is excellent.

Moreover, since it becomes the above structure, replacement | exchange of the circuit board 70 from the sensor adapter 40 is easy, and it is excellent in productivity.
Even if the function is not changed or added, it is necessary to replace the circuit board 70 with a new one when it has been used for many years. However, since the replacement is easy, the maintenance is excellent.

  In addition, even if the sensor adapter 40 is attached to the fire sensor 20 and the existing sensor base 50, it is not necessary to make a large hole in the installation surface such as the ceiling 30, so that the installation surface can be restored when the installation location is changed. There is no such thing as a big deal.

  Further, by attaching the sensor adapter 40 to the fire sensor 20 and the existing sensor base 50, the space that can be mounted on the fire sensor 20 or the existing sensor base 50 via the sensor adapter 40 increases. Even if there are parts or the like to be mounted other than the substrate 70, it is easy to mount.

Embodiment 2. FIG.
FIG. 9 is a front perspective view of the adapter cover 80 of the sensor adapter according to the second embodiment of the present invention.
Hereinafter, the second embodiment will be described, but those overlapping with the first embodiment will be omitted.
In the second embodiment, the concave portion 82 is provided in the side surface portion 81 of the adapter cover 80, but the board pressing portion 42B provided in the adapter cover 40B of the first embodiment is not provided.
For this reason, when an electronic component having a height is mounted, the thickness of the circuit board 70 also increases. However, the adapter cover 80 can be attached to the circuit board 70 having a greater thickness than the adapter cover 40B.

However, if the circuit board 70 is attached to the sensor adapter 40 as it is, it moves within the sensor adapter 40 (between the adapter main body 40A and the adapter cover 40B), and the electrode pattern 73 of the circuit board 70 and the terminals of the adapter main body 40A. There is a possibility that the portion 42A is not in contact with the portion 42A and is not conductive.
Therefore, the above problem can be solved by fixing the electrode pattern 73 of the circuit board 70 to the terminal portion 42A of the adapter main body 40A by soldering.

  The above problem can also be solved by making the circuit board 70 one size larger and holding the circuit board 70 by the side face portion 41B so that there is no gap between the side face of the circuit board 70 and the side face portion 41B.

  The above problem can also be solved by increasing the thickness of the bottom surface 83 of the adapter cover 80 and pressing the circuit board 70 with the entire adapter cover 80 other than the side surface portion 41B.

  Note that the shapes of the board housing portion 44A, the circuit board 70, and the adapter covers 40B and 80 are not limited to these.

  In the present embodiment, the circuit board 70 has a concave recess 43B and the adapter main body has a convex protrusion 45A. However, the circuit board 70 and the adapter main body 40A have a concave shape and a convex shape, respectively. The opposite may be provided.

  1 Fire Receiver, 3 Sensor Line, 3A Common Line, 3B Line Line, 10 Control Circuit, 11 Constant Voltage Circuit, 12 Receiver Circuit, 13 Discrimination Circuit, 14 Disconnection Circuit, 15 Termination Resistance, 20 Fire Detector, 21 Case body, 22 (case body) surface, 23 (case body) extension, 24 (case body) lid, 25 smoke detection unit, 26 (case body) opening, 27 (case body) Back surface, 30 ceiling (installation surface), 40 sensor adapter, 40A adapter body, 41A (adapter body) blade bracket, 42A (adapter body) terminal section, 43A hook (locking means), 44A substrate storage section, 45A Convex part (first fitting part), 46A Back surface of adapter body, 47A Blade fitting, 40B Adapter cover, 41B Side surface part, 42B Substrate pressing Part, 43B concave part (second fitting part), 50 sensor base, 51 (sensor base) terminal part, 52 (sensor base) blade receiving bracket, 53 screw insertion hole, 54 lead-in port, 70 circuit board , 71 hole part, 72 contact part, 73 electrode pattern, 80 adapter cover, 81 side part, 82 recessed part, 83 bottom face, 100 fire alarm equipment.

Claims (5)

A fire sensor is provided between a sensor base attached to the installation surface and connected to a sensor line extending from a fire receiver, and the fire sensor and the fire sensor via conductive terminals. A sensor adapter connected to the sensor base,
An adapter body;
A circuit board detachably provided on the adapter body,
The adapter body is
In order to store the circuit board, a board storage part that is recessed deeper than the height of the circuit board;
An adapter for a sensor, comprising: locking means provided on the terminal portion and locking the circuit board. An adapter cover for protecting the circuit board;
The adapter cover is
2. The sensor adapter according to claim 1, further comprising a second fitting portion that is fitted to a first fitting portion provided in the substrate housing portion and is attached to the adapter main body. A sensor base attached to the installation surface and connected to a sensor line extending from the fire receiver; and an adapter main body attached between the fire sensor;
An adapter cover that protects a circuit board provided with an electrode pattern around the hole and the hole,
The adapter body is
A substrate storage portion recessed to store the circuit board;
A first fitting portion provided on a side surface of the substrate storage portion;
A conductive terminal portion that conducts with the sensor line through the sensor base;
A hook provided on the terminal portion,
The adapter cover is
The outer periphery of the adapter cover, and a side surface provided to cover the side surface of the circuit board;
A second fitting portion provided on the side surface portion,
After the hole is hung on the hook, the terminal part and the electrode pattern are in contact with each other, and the circuit board is accommodated in the board accommodating part so as to be conductive,
The adapter for a sensor, wherein the adapter cover is attached to the adapter main body by fitting the first fitting portion and the second fitting portion. The circuit having a termination resistor, receiving an abnormal signal from the fire detector via the sensor line, and having a function of disconnecting the termination resistor from the sensor line when the abnormal signal is received The sensor adapter according to claim 3, wherein a substrate is mounted. The adapter cover has a board pressing portion,
When the adapter cover is attached to the adapter body,
5. The sensor adapter according to claim 3, wherein the circuit board is fixed by pressing the circuit board toward the board storage part with the board pressing part.

Images