JPH0765265A - Wireless fire sensor - Google Patents

Abstract

PURPOSE:To properly perform detection in case of the detachment of the wireless fire sensor is detached by simple constitution without using a mercury switch which is generally expensive and dangerous. CONSTITUTION:The wireless fire sensor has a couple of terminals 4 and 4a provided at specific positions of a housing case 1, a conductive rolling body 9 which comes into contact with the couple of terminals 4 and 4a to form an electric short circuit between those terminals 4 and 4a, and a slanting surface 8 which guides the rolling of the rolling body 9 so that the conductive rolling body 9 contacts and leaves the couple of terminals 4 and 4a according to variation in the angle of the housing case 1; and then the housing case 1 slants at more than a certain angle and then if the electric short circuit is formed between the terminal 4 and 4a or reset, an alarm signal indicating the detachment of the fire sensor is outputted by radio from a wireless transmitting means.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a wireless fire detector,
More specifically, the present invention relates to a wireless fire detector of a type having a so-called tamper function that wirelessly transmits a notification signal to that effect to a predetermined receiver when it is detached from a predetermined installation place such as a ceiling of a house.

[0002]

2. Description of the Related Art Conventionally, a wireless fire detector of this type has been proposed which includes a so-called mercury switch. This is because when the fire detector is properly installed in a horizontal state, the mercury 21 in the mercury switch 20 electrically short-circuits the pair of terminals 22, 22a as shown in FIG. 7 (a). However, when the fire detector is removed from the ceiling surface and tilted, the mercury 21 in the mercury switch 20 moves and the terminal 2 moves, as shown in FIG. 7B.
The short-circuited state between 2 and 22a is released. Then, when the short-circuited state is released, a notification signal indicating that the fire detector has been removed is wirelessly output from a predetermined wireless transmission unit provided in the fire detector. According to such a configuration,
There is an advantage that the fact can be detected not only when the fire detector is detached from the ceiling surface and removed, but also when the fire detector is detached together with the ceiling plate.

[0003]

However, the conventional mercury switch 20 is generally expensive and the manufacturing cost of the fire detector is high. Further, the mercury switch 20 is damaged and the inside thereof is damaged. There was also a risk in the case of mercury 21 flowing out.

The present invention has been proposed in view of the above point, and it is possible to accurately detect the improper removal of the fire detector itself without using expensive and dangerous parts such as a mercury switch, and it is safe and inexpensive. The purpose is to provide a wireless fire detector that can be manufactured by.

[0005]

A wireless fire detector according to the present invention as set forth in claim 1, which is proposed to achieve the above object, has a fire detecting means and when a fire is detected by the fire detecting means. And a wireless transmission means for wirelessly outputting a notification signal to that effect and a wireless fire detector housed in the housing chamber of the housing case, the wireless fire sensor projecting to a position outside the wall surface partitioning the housing chamber of the housing case. State-provided pair of terminals, a conductive rolling element that causes an electrical short circuit between the pair of terminals by contact with the pair of terminals, and the conductive rolling element changes the angle of the housing case. According to the above, the inclined surface for guiding the rolling motion of the rolling element so as to come into contact with and separate from the pair of terminals, and the wireless transmission means has a housing casing. When the electric short circuit occurs or the electric short circuit is released due to the inclination of the battery at a certain angle or more, it is configured to wirelessly output a notification signal indicating that the fire detector has been removed. ing.

A wireless fire detector according to a second aspect of the present invention is the wireless fire detector according to the first aspect, wherein the wireless transmission means has a predetermined electrical short between the pair of terminals or cancellation of the electrical short. It is configured to wirelessly output a notification signal indicating that the fire detector has been removed only when it is continuously performed for a certain time or longer.

[0007]

In the wireless fire detector according to the present invention as set forth in claim 1, the electrically conductive rolling element rolls along a predetermined inclined surface when the housing case is inclined by a certain angle or more. Then, by moving and contacting or separating from the pair of terminals, an electrical short circuit occurs between the pair of terminals or release of the electrical short circuit occurs. Then, the wireless transmission means wirelessly outputs a notification signal indicating that the fire detector has been removed. Therefore, if the wireless fire detector that was installed horizontally on the ceiling surface etc. is tilted by itself or by removing it together with the ceiling surface,
That fact can be appropriately detected. It is not necessary to use a mercury switch to detect such fire detector removal. The pair of terminals are provided so as to project to the outside of the housing chamber in the housing case housing the fire detection means and the wireless transmission means, and the conductive rolling element rolls outside the housing chamber. The rolling element does not cause trouble by contacting each electric circuit such as the fire detection means and the wireless transmission means.

In the wireless fire detector according to the present invention as set forth in claim 2, the electrical short circuit between the pair of terminals or the cancellation of the electrical short circuit is only temporarily made within a predetermined short time. If not, the wireless output of the notification signal indicating that the fire detector has been removed from the wireless transmission means is not performed. Therefore, even if a situation occurs in which a conductive rolling element temporarily separates from or comes into contact with a pair of terminals due to shaking such as an earthquake, this is erroneously regarded as the removal of the fire detector. There is no fear of making a decision.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view showing a schematic configuration of a wireless fire detector K according to the present invention, and FIG. 2 is a plan view thereof. The wireless fire detector K includes a housing case 1 formed of a synthetic resin or the like in an appropriate shape such as a hollow disk shape, a printed circuit board 3 housed in a housing chamber 2 formed in the housing case 1, This printed circuit board 3
It is provided with a pair of pin-shaped terminals 4 and 4a protrudingly provided on the steel plate, a steel ball 9 as a conductive rolling element, and the like.

Of the above, the printed circuit board 3 has an electric component (not shown) which constitutes a fire detecting portion for judging the presence or absence of a fire depending on whether or not smoke is flowing into the smoke introducing portion 5.
And a wireless transmission circuit 6 that wirelessly transmits a notification signal to that effect to a specific wireless receiver when it is determined that a fire has occurred in the fire detection unit. However, the wireless fire detector K may be a type that detects a fire by heat detection or the like, instead of a type that detects a fire by smoke detection.

The housing case 1 has a groove portion 7 having a constant width b formed on the upper surface thereof, and a steel ball 9 is provided in the groove portion 7.
Is housed. The upper wall surface portion 1a of the accommodation chamber 2 corresponding to the bottom surface portion of the groove portion 7 is formed as an inclined surface 8 which becomes lower toward the center of the housing case 1, and when the housing case 1 is in a horizontal state, the height is increased. Lowest groove 7
The steel ball 9 is located at the center of the groove, and when the housing case 1 is tilted, the steel ball 9 rolls toward the end of the groove 7. In the present invention, instead of the steel ball 9,
For example, a steel roller or the like may be adopted and the roller may roll along the inclined surface 8. Further, the material may be any material as long as it has conductivity, and other materials may be applied.

The lower portions of the pair of terminals 4, 4a are connected to the printed circuit board 3, but the upper portions thereof penetrate the upper wall surface portion 1a of the housing case 1 and the slanted surface 8 has the lowest height. It is provided in a non-contact standing state in the central portion of 7. As a result, when the housing case 1 is in the horizontal state, the steel balls 9 come into contact with both of the pair of terminals 4, 4a, and the terminals 4, 4a are electrically short-circuited via the steel balls 9. It becomes a state.

In FIG. 3, the pair of terminals 4, 4a are provided.
The terminal 4 on one side is connected to the power supply Vdd, and the terminal 4a on the other side is connected to the tamper input terminal T of the wireless transmission circuit 6. When the voltage value of the signal input to the tamper input terminal T becomes a low voltage below a certain value, the wireless transmission circuit 6 wirelessly outputs a notification signal indicating that the fire detector K has been removed at that time. Is configured. A resistor R and a capacitor C are connected in the middle of the tamper input wiring, so that the tamper input terminal T is provided within a fixed short time.
It is configured so that the voltage value of the signal input to is compensated above a certain value.

Next, the wireless fire detector K having the above structure
The action of will be described. First, when the fire detector K is mounted on the ceiling of a house for use, the housing case 1 is mounted in a horizontal state as shown in FIG. In such a mounting posture, the steel ball 9 has the pair of terminals 4,
Since the terminals 4 and 4a are in contact with each other and the terminals 4 and 4a are short-circuited to each other, a signal of a certain voltage or more is continuously input from the power supply Vdd to the tamper input terminal T of the wireless transmission circuit 6, and the wireless transmission circuit 6 Keeps the normal waiting state.

However, in such a state, if the fire detector K is removed from the ceiling surface or the ceiling plate is removed together with the maliciousness of an outsider or an error of an operator, as shown in FIG. The fire detector K tilts. Then, when the inclination angle θ becomes a certain angle or more,
The steel ball 9 separates from the terminals 4 and 4a and rolls along the inclined surface 8 toward the end portion side of the housing case 1, and these terminals 4 and 4a are rolled.
Since the short-circuited state between “a” is released, the tamper input from the power supply Vdd to the wireless transmission circuit 6 is stopped. Then, as shown by an arrow A in FIG. 5A, the voltage H of the tamper input to the wireless transmission circuit 6 becomes lower than a predetermined voltage value Vs, and as shown in FIG. A notification signal indicating that the fire detector K has been removed is wirelessly output from 6. Therefore, when this is received by the receiver, it can be properly detected that the fire detector K has been improperly removed, and the countermeasure can be promptly taken. The time indicated by arrow B in FIG. 5A is the time when the restoration is performed. Further, the notification signal indicating that the fire detector K has been removed may be wirelessly output intermittently instead of continuously.

Next, even if the fire detector K is not removed as described above, the steel ball 9 vibrates due to an earthquake or the like, and the steel ball 9 temporarily or from the terminals 4, 4a. There may be intermittent separation. However, even if the tamper input from the power supply Vdd to the wireless transmission circuit 6 is stopped due to such vibration, if the stop time is short, the charge stored in the capacitor C is stored in the wireless transmission circuit 6. 6 (a), the voltage value of the tamper input signal input to the wireless transmission circuit 6 does not drop so much by being supplied to the tamper input terminal T. Therefore, when the steel ball 9 only vibrates due to vibration such as an earthquake, the notification signal indicating that the fire detector K has been removed will not be erroneously output from the wireless transmission circuit 6.

In the above embodiment, the steel ball 9 contacts the pair of terminals 4, 4a when the fire detector K is in the horizontal state, but the present invention is not limited to this. For example, when the fire detector K is in the horizontal state, the steel ball 9 remains separated from the pair of terminals 4, 4a, and when the fire detector K is improperly tilted, the steel ball 9 is kept in the terminals 4, 4a. May be contacted with. In this case, the steel ball 9 is connected to the terminal 4,
The wireless transmitter circuit 6 may be configured to output a predetermined notification signal when the terminals 4 and 4a are electrically short-circuited by contacting the terminal 4a.

[0018]

As can be understood from the above description, according to the present invention as set forth in claims 1 and 2, when the housing case is tilted by a certain angle or more, a pair of electrically conductive rolling elements such as steel balls are formed. When the terminals come into contact with or separate from each other and an electrical short circuit or cancellation of the electrical short circuit occurs between the pair of terminals,
The wireless fire detector was removed without using the mercury switch, which is relatively expensive and dangerous as in the past, because the notification signal indicating that the fire detector has been removed is wirelessly output from the wireless transmission means. In this case, it is possible to perform accurate detection. As a result, no expensive parts are required, the manufacturing cost of the wireless fire detector can be reduced, there is no harm from mercury, and the safety in handling can be improved.

Particularly, according to the present invention as set forth in claim 2,
If the electrical short circuit between the pair of terminals or the release of the electrical short circuit occurs only temporarily due to shaking such as an earthquake,
Since the wireless output of the notification signal indicating that the fire detector has been removed is not performed wirelessly, it is possible to prevent an erroneous determination regarding removal of the fire detector and to improve the reliability thereof.

[Brief description of drawings]

FIG. 1 is a sectional view showing an example of a wireless fire detector according to the present invention.

FIG. 2 is a plan view of the wireless fire detector shown in FIG.

FIG. 3 is an explanatory diagram showing an example of a connection state between a pair of terminals of a wireless fire detector and a wireless transmission circuit according to the present invention.

4 is a sectional view showing an example of a state in which the wireless fire detector shown in FIG. 1 is inclined.

5A and 5B are time charts showing the relationship between tamper input to the wireless transmission circuit and wireless output.

6A and 6B are time charts showing a relationship between a tamper input to a wireless transmission circuit and a wireless output when a vibration such as an earthquake is received.

7 (a) and 7 (b) are explanatory diagrams showing an example of a mercury switch used in a conventional wireless fire detector.

[Explanation of symbols]

 1 Housing Case 2 Storage Room 3 Printed Circuit Board 4, 4a Terminal 5 Smoke Inlet 6 Wireless Transmission Circuit 7 Groove 8 Slope 9 Steel Ball (Conductive Rolling Body) K Wireless Fire Detector

Claims (2)

[Claims] 1. A wireless fire detector in which a fire detection means and a wireless transmission means for wirelessly outputting a notification signal to that effect when a fire is detected by the fire detection means are housed in a housing chamber of a housing case. In order to cause an electrical short circuit between the pair of terminals provided in a projecting state to the outer side of the wall surface partitioning the accommodating chamber of the housing case and the contact between the pair of terminals. And a sloped surface that guides the rolling of the rolling element so that the electrically conductive rolling element comes into contact with and separates from the pair of terminals according to an angle change of the housing case. Moreover, in the wireless transmission means, when the housing case is tilted by a certain angle or more, an electrical short circuit is caused between the pair of terminals or the electrical short circuit is released. The wireless fire detector is configured to wirelessly output a notification signal indicating that the fire detector has been removed. 2. The fire detector according to claim 1, wherein the wireless transmission means is provided with a fire detector only when an electrical short circuit between the pair of terminals or cancellation of the electrical short circuit is continuously performed for a predetermined period of time or more. A wireless fire detector, which is configured to wirelessly output a notification signal indicating that it has been removed.