JPH06111154A - Fire sensor - Google Patents

Abstract

PURPOSE:To provide a fire sensor constituted of a tamper switch having extremely excellent durability. CONSTITUTION:An engaging click 1b to be engaged with a sensor body 1A at the time of attaching the body 1A to a sensor base 1B and elastically deformed at a process of separating the body 1A from the base 1B is provided in the base 1B, and a normally-open switch 7b to be driven only when the click 1b is elastically deformed is provided in the body 1A. The switch 7b is closed only for a short time when the body 1A is attached to the base 1B and the body 1A is separated from the base 1B.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention comprises a sensor body for detecting a fire and a sensor base installed on a mounting surface such as a ceiling and to which the sensor body is detachably mounted. The present invention relates to a fire detector which detects a separated state of a main body and the detector base and transmits a tamper signal.

[0002]

2. Description of the Related Art FIGS. 6 and 7 are views showing a conventional example of a fire detector. FIG. 6 shows a mounted state of the detector body and the detector base, and FIG. 7 shows the detector body and the detector body. 3 shows a sensor-based separation state.

As shown in FIGS. 6 and 7, a conventional fire detector 1 is installed on a detector body 1A for detecting a fire and a mounting surface such as a ceiling, and the detector body 1A is detachably mounted. The sensor base 1B is made up of. The sensor body 1A detects a fire factor such as smoke or heat by the sensing block 4, and the detection signal is processed by a processing circuit (not shown) provided on the circuit board 3 to output a fire signal. It has become.

In order to prevent the sensor body 1A from being stolen, the conventional fire sensor 1 detects the separated state of the sensor body 1A and the sensor base 1B and detects the separated state. It has a function to send out a tamper signal for notification (hereinafter referred to as "tamper function"). 6 and 7, reference numeral 6 is a tamper switch for detecting the separated state of the sensor body 1A and the sensor base 1B. The tamper switch 6 includes a normally closed switch 6a mounted on the circuit board 3 and a push button 6 of the normally closed switch 6a.
It is composed of a spring 6b for pressing c.
6B and 7B are circuit diagrams of the tamper switch 6, in which the detection circuit 5 detects the closed state of the normally closed switch 6a from the input T, and the tamper signal is detected. Is wirelessly transmitted to a receiver (not shown) or the like that monitors the fire detector 1.

As shown in FIG. 6 (a), the tamper switch 6 has the spring 6b fixed to the sensor base 1B when the sensor body 1A and the sensor base 1B are mounted. The push button 6c of the normally closed switch 6a built in the sensor body 1A is constantly pressed by force. At this time, the normally-closed switch 6a is in the open state, that is, the operating state as shown in FIG. 6B, and since a high level voltage is not input to the input T of the detection circuit 5, the detection circuit 5 outputs the tamper signal. Do not output.

Here, when the sensor body 1A is stolen,
When the sensor body 1A is detached from the sensor base 1B and separated, as shown in FIG. 7A, the push button 6c of the normally closed switch 6a is pressed by the spring 6b, that is, the operating state. Is released. At this time, the normally closed switch 6a is closed as shown in FIG. 7 (b), the high level voltage V is input to the input T of the detection circuit 5, and the detection circuit 5 outputs the tamper signal as described above. Wirelessly transmit to the receiver, and the sensor body 1A
Has been removed from the sensor base 1B.

[0007]

However, in the conventional structure, the sensor main body 1A and the sensor base 1 are provided.
In a mounted state with B, that is, in a normal state, the spring 6b is constantly pressing the push button 6c of the normally closed switch 6a, so that the spring 6b is apt to deteriorate due to metal fatigue. Similarly, in the normal state, since the normally closed switch 6a is in the normally open state, that is, in the operating state, the components of the normally closed switch 6a are easily deteriorated, and the function of the tamper switch is extremely deteriorated. There was a problem that it was easy.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a fire detector including a tamper switch having extremely excellent durability.

[0009]

The present invention, which has been made to solve the above-mentioned problems, comprises a sensor body for detecting a fire and a sensor base to which the sensor body is detachably mounted. A fire detector adapted to detect a separation state between the sensor body and the sensor and to emit a tamper signal, wherein the sensor body is engaged with the sensor body when the sensor body is mounted on the sensor base. In addition, an engaging claw that is elastically displaced in the process of separating the sensor main body from the sensor base is provided on the sensor base, and a switch that is activated only when the engaging claw is elastically displaced is a sensor. The fire detector is provided in the main body, and is adapted to emit the tamper signal in accordance with an operating state of the switch.

[0010]

In the present invention, the switch is activated only when the engaging claw is elastically displaced in the process of separating the sensor body from the sensor base. Very little deterioration and breakdown.

[0011]

The present invention will be described below with reference to the drawings showing its embodiments. The same components as those of the conventional example are designated by the same reference numerals.

1 to 3 are sectional views showing a fire detector 1 according to an embodiment of the present invention. Fire detector 1 of the embodiment of the present invention
Is a detector body 1A for detecting a fire, as in the conventional case,
From a sensor base 1B installed on a mounting surface such as a ceiling and to which the sensor body 1A is detachably mounted, and a tamper switch 7 for detecting a separated state of the sensor body 1A and the sensor base 1B. It is configured. The sensor body 1A detects a fire factor such as smoke or heat by the sensing block 4, and the detection signal is processed by a processing circuit (not shown) provided in the built-in circuit board 3 to output a fire signal. It is designed to output.

Incidentally, FIG. 3 shows a mounted state of the sensor body 1A and the sensor base 1B, and FIG. 2 shows the sensor body 1.
FIG. 1 shows a separated state of A and the sensor base 1B, and FIG. 1 shows a moment of a process of separating or mounting the sensor body 1A and the sensor base 1B.

As shown in FIGS. 1 and 3, the sensor base 1B is integrally formed with an engaging claw 1b that engages with the sensor body 1A when the sensor body 1A is mounted. The sensor body 1A is provided with a claw receiving hole 1d with which the engaging claw 1d engages. Figure 3
As shown in FIG. 3, when the sensor body 1A is mounted on the sensor base 1B, the engaging claws 1b of the sensor base 1B are engaged with the claw receiving holes 1d of the sensor body 1A. At the same time, the engaging hook portion 1a provided on the sensor body 1A is in engagement with the hook receiving hole 1c provided on the sensor base 1B.

The tamper switch 7 has a push button 7c.
It is composed of a normally open switch 7a which is in a closed state, that is, an operating state when pressed by the button, and an interlocking plate 7b which is rotationally displaced by the elastic displacement of the engaging claw 1b to press the push button 7c of the normally open switch 7a. The normally open switch 7a
The normally open switch 7a is closed only when the push button 7c is pressed. The normally open switch 7a is mounted on the circuit board 3, and the interlocking plate 7b is rotatably attached to the inner wall of the sensor body 1A. As shown in FIG. 1, the engagement claw 1b provided on the sensor base 1B is elastically displaced, and the engagement claw 1b is manually pressed in the direction of an arrow F in the drawing. When the engagement claw 1b is elastically displaced so as to bend back, the interlocking plate 7b is angularly displaced, and the interlocking plate 7b presses the push button 7c of the normally open switch 7a. The engaging claw 1b is indicated by an arrow F in the figure.
The push button 7c of the normally open switch 7a is in a pressed state only when it is pressed in the direction. When the pressing force is removed from the engaging claw 1b, the engaging claw 1b returns to its original state by its elastic return force. The pressed state of the push button 7c of the normally open switch 7a is released, and the normally open switch 7a is opened.

Incidentally, as shown in FIG. 3, the sensor base 1B is provided.
The sensor body 1A attached to the sensor base 1
In the case of separating from B, first, as shown in FIG. 1, the engaging claw 1b engaged with the sensor main body 1A is indicated by an arrow F in the figure.
It is pressed in the direction and elastically displaced. Then, as shown in FIG. 1, the engaging claw 1b angularly displaces the interlocking plate 7b, and the interlocking plate 7b presses the push button 7c of the normally open switch 7a to close the normally open switch 7a. It becomes a state, that is, an operating state. Then, as shown in FIG. 1, the sensor body 1 is moved with the engaging claw 1b elastically displaced.
A is pulled away from the sensor base 1B. At that time, since the engaging claw 1b is separated from the interlocking plate 7b, the push state of the push button 7c of the normally open switch 7a is released and the normally open switch 7a is brought into the open state, that is, the non-operating state.

Further, as shown in FIG. 2, the sensor base 1B is provided.
The sensor body 1A separated from the sensor base 1
When mounting on B, first, the engaging hook 1a is inserted into the hook receiving hole 1c, and the sensor body 1A is pressed against the sensor base 1B. Then, the engaging claw 1b of the sensor base 1B is elastically displaced so as to warp back in the direction of arrow F in the figure as in the state of FIG. 1, and the engaging claw 1b rotates the interlocking plate 7b as shown in FIG. In addition to the dynamic displacement, the interlocking plate 7b causes the normally open switch 7
When the push button 7c of a is pressed, the normally open switch 7a is closed, that is, in the operating state. Then, the engaging claw 1b returns to the original state at the position of the claw receiving hole 1d and is engaged with the claw receiving hole 1d. At this time, normally open switch 7a
Is released from the normally open switch 7a.
Is in the open state, that is, the non-operating state.

By the way, in the fire detector 1 of this embodiment, the normally open switch 7a is in the open state (non-operating state).
The transmission state of the tamper signal is inverted every time when the state changes from the closed state to the closed state (operating state). That is, the tamper signal is always wirelessly transmitted in the separated state of the sensor body 1A and the sensor base 1B, and when the sensor body 1A is attached to the sensor base 1B. The tamper signal is not always transmitted. That is, the fire detector 1 transmits the tamper signal according to the operating condition of the normally open switch 7a.

FIG. 4 is a circuit diagram of essential parts of the fire detector 1 according to the embodiment of the present invention. In FIG. 4, reference numeral 9 denotes an inverting circuit, which is a circuit for inverting the output each time the normally open switch 7a shifts from the open state (non-operating state) to the closed state (operating state). That is, FIG. 4 shows a circuit relating to the tamper switch 7, and the circuit is composed of the normally open switch 7a, the inverting circuit 9 and the detection circuit 5 (similar to the conventional example). . The inverting circuit 9 is mainly composed of a flip-flop circuit 8. The flip-flop circuit 8 is, for example, a CMOS integrated circuit “μPD
Preset input (NPR) represented by 74HC74 "
And a D-type flip-flop circuit with a reset input (NR). The operation of the flip-flop circuit 8 will be described below.

When the preset input (NPR) is “H” level (high level) and the reset input (NR) is “L” level (low level), the inverted output (NQ) is “H” level.

When the preset input (NPR) is at “H” level and the reset input (NR) is at “H” level, the clock input (CLK) is from “L” level.
When it shifts to the H "level, the level of the inverted output (NQ) is inverted.

In the inverting circuit 9, a power source (V) is connected to the preset input (NPR), and the reset input (NR) is composed of a resistor r and a capacitor C.
The power source (V) is connected through an R circuit, the inverted output (NQ) is connected to the input T of the detection circuit 5, and the clock input (CLK) is connected to the normally open switch 7a. The power source (V) is connected via
The inverted output (NQ) and the input (D) are connected. The detection circuit 5 detects the output level of the inverting circuit 9 from the input T, and sends the tamper signal to a receiver (not shown) or the like only when the inverting output (NQ) is in the H ″ level state. It is designed to transmit wirelessly.

FIG. 5 is a time waveform diagram showing the operating state of the circuit of FIG. The circuit of FIG.
It operates as shown in.

First, when the power source (V) is turned on in a state where the sensor body 1A and the sensor base 1B are separated, the preset input (NPR) is immediately set to the “H” level as shown in (d). As
As shown in (c), the reset input (NR) is the CR.
Due to the delay action of the circuit, the "L" level gradually shifts to the "H" level. At this time, the preset input (NPR) is at "H" level and the reset input (NPR) is
Since R) has a moment of "L" level, the inverted output (NQ) becomes "H" level as shown in (b). The ”
The detection circuit 5 detects the H "level from the input T, and the detection circuit 5 wirelessly transmits a tamper signal.

Next, in a process of mounting the sensor body 1A on the sensor base 1B, that is, in a state where the engagement claw 1b is elastically displaced, the normally open switch 7a is closed to input the clock. (CLK) becomes "H" level. At this time, the inverted output (NQ) that was at the “H” level is inverted to become the “L” level. After that, when the engagement claw 1b engages with the claw receiving hole 1d and the sensor body 1A is completely attached to the sensor base 1B, the normally open switch 7a opens. The inverted output (NQ) maintains the "L" level.

Next, in the process of separating the sensor body 1A from the sensor base 1B, that is, in a state where the engaging claw 1b is elastically displaced, the normally open switch 7a.
Are closed and the clock input (CLK) becomes "H" level. At this time, the inverted output (NQ) that was at the “L” level is inverted to become the “H” level, and the detection circuit 5 detects the “H” level from the input T, and the detection circuit 5
Sends a tamper signal wirelessly. After that, when the sensor body 1A is completely separated from the sensor base 1B, the normally open switch 7a is opened, but the inverting output (NQ) maintains "H" level, and The detection circuit 5 continues to wirelessly transmit the tamper signal.

Therefore, in the fire detector 1 of this embodiment, the tamper signal is always wirelessly transmitted in a state where the detector body 1A is separated from the detector base 1B.

In the fire detector 1 according to the embodiment of the present invention constructed as described above, the normally open switch 7a is provided only for an extremely short time during the process of attaching and detaching the detector body 1A to and from the detector base 1B. It becomes a closed state, that is, an operating state. That is, the sensor body 1A is the sensor base 1B.
In the normal state in which the sensor body 1A is attached to the sensor body 1A and in the state where the sensor body 1A is completely separated from the sensor base 1B, the normally open switch 7a is always open, so that the normally open switch 7a is not subject to any mechanical load. Therefore, the durability and the long life of the normally open switch 7a are remarkably improved as compared with the conventional one.

By the way, in this embodiment having the above-mentioned configuration, the engaging claw 1b may be provided on the sensor body 1A and the tamper switch 7 may be provided on the sensor base 1B. Further, instead of the normally open switch 7a, the tamper switch may be a normally closed switch. Further, the normally open switch 7a is activated at least in the process of separating the sensor body 1A from the sensor base 1B, and is inactivated when the sensor body 1A is attached to the sensor base 1B. Any structure will suffice.

[0030]

According to the present invention configured as described above, the switch is activated only for an extremely short time in the process of separating the sensor body from the sensor base. The fire sensor can be configured with a tamper switch having extremely excellent durability because the deterioration and the failure of the switch are extremely reduced.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a separation or mounting process in a fire detector 1 according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a separated state of the fire detector 1.

FIG. 3 is a cross-sectional view showing a mounted state of the fire detector 1.

FIG. 4 is a circuit diagram of a main part of the fire detector 1.

FIG. 5 is a time waveform diagram showing an operating state of the fire detector 1.

FIG. 6 is a cross-sectional view showing a conventional fire detector 1 (mounted state) and a circuit diagram of a main part.

FIG. 7 is a cross-sectional view showing a conventional fire detector 1 (separated state) and a circuit diagram of a main part.

[Explanation of symbols]

 1 Fire Detector 1A Detector Main Body 1B Detector Base 1b Engaging Claw 7 Tamper Switch 7a Normally Open Switch 7b Interlocking Plate

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[Procedure amendment]

[Submission date] January 13, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0005

[Correction method] Change

[Correction content]

As shown in FIG. 6A, the tamper switch 6 has a push button 6c of the normally closed switch 6a when the sensor body 1A and the sensor base 1B are mounted.
The spring 6b fixed to the
We are constantly pressing the push button 6c. At this time, the normally-closed switch 6a is in the open state, that is, the operating state as shown in FIG. 6B, and since a high level voltage is not input to the input T of the detection circuit 5, the detection circuit 5 outputs the tamper signal. Do not output.

[Procedure Amendment 2]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 7

[Correction method] Change

[Correction content]

[Figure 7]

Claims (1)

[Claims] 1. A sensor body for detecting a fire, and a sensor base to which the sensor body is detachably mounted,
A fire detector for transmitting a tamper signal by detecting a separation state between the detector body and the detector, wherein the detector body engages with the detector body when the detector body is mounted on the detector base. In addition, an engaging claw that is elastically displaced in the process of separating the sensor main body from the sensor base is provided on the sensor base, and a switch that is activated only when the engaging claw is elastically displaced is provided in the sensor. A fire detector, which is provided in a main body and is adapted to emit the tamper signal in accordance with an operating state of the switch.