JP2001101541A - Fire sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a superior fire sensor capable of recognizing the present degree of contamination or deterioration of its fire sensing section. SOLUTION: This fire sensor which automatically corrects its fire discriminating level in accordance with the degree of contamination of its fire sensing section is provided with a smoke detecting section which detects the concentration of smoke, a sensitivity correction calculating section 2 which calculates the correction value of a preset prescribed fire discriminating level in accordance with the degree of contamination or deterioration the smoke detecting section, and a smoke density outputting section 4 which discriminates the occurrence of a fire by comparing the concentration level of smoke detected by means of the smoke detecting section with the present fire discriminating level and, in addition, corrects the fire discriminating level in steps based on the correction value from the calculating section 2. The detector is also provided with a contamination level outputting section 2 which generates a contamination level based on the correction value from the calculating section 2 and, at the same time, outputs the level. Therefore, the contamination level of the smoke detecting section can be confirmed from the outside.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fire detector having a so-called automatic compensation function for automatically correcting a fire determination level in accordance with the degree of contamination of a fire detector.

[0002]

2. Description of the Related Art Conventionally, a fire detector detects a smoke density and an environmental temperature, and outputs a fire signal (not shown) when those levels exceed a preset fire determination level.
For a fire detector that is not connected to a fire receiver, a sound device such as a speaker or a display device such as an LED is used to notify the user.

For example, FIG. 4 shows a structure of a general photoelectric smoke detector. In this figure, dust and dirt accumulate on an inner wall, a light receiving portion J, a light projecting portion T, and the like, and internal scattering light is generated. The sensitivity changes due to an increase or decrease, attenuation of the front transmittance of the light receiving unit J, and the light projecting unit T. The sensitivity of the fire detector changes due to dirt compared to the initial period, which may hinder the initial discovery of fire,
There have been problems such as increased sensitivity and increased false information. Therefore, a sensor having an automatic sensitivity correction function for correcting the sensing sensitivity for the smoke amount whose base sensitivity has been changed by comparing the received light amount in the normal state with the initial level has been commercialized.

In a sensor having such an automatic sensitivity correction function, generally, the detection sensitivity of smoke density and environmental temperature is lowered due to contamination of the surface and inside of the sensor and deterioration of the detection element, and the fire determination level is reduced. In order to prevent the temperature from becoming relatively low, the fire discrimination level is automatically increased to guarantee operation suitable for a real environment. That is, as shown in FIG. 3A, as the dirt advances, FIG.
As shown in FIG. 3C, the sensitivity is increased, but is corrected each time as shown in FIG. 3C, and the normal output is constant as shown in FIG.

When the amount of correction of the fire discrimination level exceeds a predetermined warning level when dirt and deterioration become severe, a dirty alarm signal is transmitted to the fire receiver or a speaker provided in the sensor body is provided. Such an acoustic device or a display device such as an LED promotes cleaning of the fire detector and replacement of the detection element.

[0006]

However, when the sensitivity is automatically corrected and the limit of correction is reached, that is, at T shown in FIGS. 3 (b) and 3 (c), an abnormality suddenly occurs, and There was a problem that I needed.

[0007] The present invention has been made in view of the above problems, and an object of the present invention is to provide an excellent fire detector capable of knowing the degree of dirt and deterioration at the present time. And

[0008]

According to a first aspect of the present invention, there is provided a fire detector having a function of automatically correcting a fire determination level in accordance with a degree of contamination of a fire detecting unit. A fire detection unit for detecting an environmental temperature; a sensitivity correction calculation unit for calculating a correction value of a predetermined fire discrimination level predetermined according to a contamination level of a degree of contamination or deterioration of the fire detection unit; A fire determination unit that compares the smoke density and temperature level detected by the unit with a preset fire determination level to determine a fire and corrects the fire determination level stepwise based on the correction value from the sensitivity correction calculation unit. ,
And a dirt level output unit for generating and outputting a dirt level based on the correction value from the sensitivity correction calculation unit, wherein the dirt level can be externally confirmed. is there.

According to the second aspect of the present invention, the first aspect is provided.
In the invention described above, the contamination level is transmitted from an external device such as an inspection tool or by infrared communication means as confirmation means for externally confirming the contamination level, and the contamination level is transmitted to the external device such as an inspection tool. Can be confirmed.

[0010] According to the third aspect of the present invention, the first aspect is provided.
In the invention described above, as a confirmation means for confirming the contamination level from the outside, when the power of the fire detector is once turned off and then turned on again, a confirmation lamp which the fire detector has the contamination level only for a certain period of time after the power is turned on. It can be confirmed by the lighting state of.

According to the third aspect of the present invention, there is provided the second aspect.
The invention described in the above description is characterized in that the sensor life is estimated based on the contamination level displayed by an inspection tool or the like, and the remaining time is displayed.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, FIG. 1 shows a first embodiment of a fire detector according to the present invention, FIG. 2 shows a second embodiment, and FIG. 3 shows a third embodiment. The first embodiment will be described in detail with reference to FIGS.

[First Embodiment] As shown in FIG. 1, the fire detector has a signal control unit (CPU 10 shown in FIG. 4 described later) including a CPU and the like for performing multiplex transmission. (A transmission unit 11 shown in FIG. 4 to be described later), a smoke detection unit 1 for detecting smoke density, and a comparison between the smoke density level detected by the smoke detection unit 1 and a preset fire determination level. A smoke density output section 4; a sensitivity correction operation section 2 for correcting the fire determination level of the smoke density output section 4; and a dirt detection signal classified in a plurality of stages in advance according to the degree of dirt or deterioration of the smoke detection section 1. A dirt level output unit 3 that generates and outputs the dirt level is provided.

The operation of the fire detector will be described below. This fire detector has an automatic compensation function, and the fire determination level of the smoke density output unit 4 is corrected stepwise by the sensitivity correction calculation unit 2 (that is, the smoke detection unit 1 monitors the normal incident light amount. While correcting the sensitivity change). This is because when the surface of the sensor or the lens inside the smoke detector 1 becomes dirty, or when the detector such as the light receiving element is deteriorated, the fire detection level of the smoke density output unit 4 is automatically raised to detect the smoke. This is to keep the sensitivity of the unit 1 constant.

The smoke detector 1 constantly detects the presence of smoke. If the smoke density level exceeds the fire determination level as a result of the comparison by the smoke density output unit 4, a fire signal is multiplexed from the transmission unit. External transmission via a line or the like. At this time, the dirt level output unit 3 also transmits a dirt detection signal generated so as to indicate the dirt level at this time, thereby transmitting a dirty alarm signal to the fire receiver as in the related art. Acoustic devices such as speakers provided in the sensor body and display devices such as LEDs make the fire detector extremely dirty and deteriorated even from the outside of the fire receiver or detector, and the time for cleaning, replacement, and inspection You can see that came.

[Second Embodiment] In this embodiment, a detector and an inspection tool TT as shown in FIG. 2 are used as confirmation means for externally confirming the dirt level in the first embodiment described above. The contamination level can be checked by connecting the external device to the transmission units T1 and T2.
The dirt level is displayed on the display unit H of the inspection tool TT. Alternatively, even when the infrared communication means is provided in an external device such as a sensor and an inspection tool, the contamination level can be similarly confirmed by an external device such as an inspection tool.

[Third Embodiment] In the present embodiment, FIG.
, The transistor TR2 and the resistors R4 and R5
Thyristor S which is turned on
After the CR is turned off and restored, the base current of the transistor TR2 is turned on and off by a control signal from a further terminal F of the CPU, and the sensor confirming light 9a provided on the sensor base 1a blinks. I have. In addition,
Such a sensor confirming lamp may be configured such that another lamp different from that provided on the sensor base 1a is provided on the sensor head 1b side and blinks it.

For example, when the power of the fire detector is once turned off and then turned on again, if the confirmation lamp of the fire detector is turned on only for a certain period of time after the power is turned on, the dirt level is determined by the lighting state. Can be confirmed.

[Fourth Embodiment] In the present embodiment, FIG.
As shown in the figure, a CPU 10 for controlling each unit, a transmission unit 11 for controlling transmission, a dirt level output unit 3 for detecting dirt sensitivity of the sensor, and a dirt sensitivity detected by the dirt level output unit 3 and a predetermined dirt sensitivity. A dirt level determination unit 13 that compares the dirt level with the dirt reference value, determines a dirt level of the sensor, a time prediction unit 14 that predicts a time to determine the dirt level, and stores the dirt level determined by the dirt level determination unit 13. A storage unit 15 for storing the time predicted by the time prediction unit 14, a display / operation unit 17 including a liquid crystal screen and operation switches, and a printer 18. Further, a period calculation unit 19 that calculates a period between the two times is provided.

The dirt level determination unit 13 as determination means is
Each time the dirt sensitivity detected by the dirt / dirt level output unit 3 is compared with a predetermined dirt reference value in a plurality of stages, and each time the dirt level of each stage of the sensor is newly determined, the time at that time is indicated by the dirt level The information is stored in the storage unit 15. Then, based on the time at which the stain level of each stage stored in the stain level storage unit 15 is determined by the time prediction unit 14, the time at which the stain level of the next stage (one level higher) is determined is predicted. For example, if the dirt level has three levels, the time at which the level has reached the first level is subtracted from the time at which the level has reached the second level, and based on the period between the levels,
The period from the second stage to the third stage is determined, and the time at which the third stage is reached is predicted.

If the dirt level has five levels, the time at which the level reaches the third level is predicted from the time at which each level of the first level and the second level has been reached. At the level of the stage, the time is predicted in order, for example, the time at which the level of the fourth stage is predicted from the time at which the level of each of the second and third stages is reached.

In this way, if the time at which the level of the next stage (or subsequent stages) is reached is known, a long-term plan for cleaning the sensor can be made in advance in advance. . If the predicted time is different from the actual time, the difference can be used as a correction value for subsequent prediction. In addition, the time prediction unit 14 may predict only the time at which the final stain level is determined. That is, it is possible to predict only the time when the dirt level reaches the final stage at which cleaning is required. In this case, the cleaning time can be known, and the cleaning operation can be performed smoothly.

The time predicted by the time prediction unit 14 is stored in a predicted time storage unit 16, and the stored predicted time is displayed on the liquid crystal screen of the display unit H of the inspection tool TT via the transmission unit 11. And can also be transmitted to the receiver.

FIG. 5 shows an example in which the display section H of the inspection tool TT is displayed as a sensor contamination status record. This means that each sensor S, which is currently at level 2 as a result of inferring the detector contamination level 3, together with the operation date (see section a) and a list of the addresses of the sensors at each level (see section b). , The period up to the level 3 is predicted and recorded (see part c). FIG. 5 shows a case where the period is expressed in months. Note that this period may be recorded together with the time predicted by the time prediction unit 14.

[0025]

According to the first to third aspects of the present invention, it is possible to know the degree of dirt and deterioration at the present time, so that it is possible to know the time to clean and to provide a fire detector capable of performing cleaning work smoothly. It has the effect that it can be provided.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a first embodiment of a fire detector according to the present invention.

FIG. 2 is a connection diagram of a second embodiment of the fire detector according to the present invention and an inspection tool.

FIG. 3 is a block diagram of a circuit showing a configuration of a third embodiment of the fire detector according to the present invention.

FIG. 4 is a block diagram showing a configuration of a fourth embodiment of a fire detector according to the present invention.

FIG. 5 is an example showing the life of the fire detector.

FIG. 6 is an explanatory diagram of an automatic compensation function of a conventional fire detector.

FIG. 7 is a view illustrating a structure of a general photoelectric smoke detector.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Smoke detection part 1a Sensor base 1b Sensor head 2 Sensitivity correction calculation part 3 Soil level output part 4 Smoke density output part 9a Sensor confirmation light 11 Transmission part 13 Level judgment part 14 Time prediction part 15 Level storage part 16 Prediction time Storage unit 17 Display / operation unit 19 Period calculation unit

 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Shoichi Oka 1048 Kazuma Kadoma, Osaka Prefecture Matsushita Electric Works Co., Ltd. F term (reference) 5C085 AA01 AA03 CA07 CA13 CA15 CA30

Claims (4)

[Claims] 1. A fire detector having a function of automatically correcting a fire determination level according to a degree of contamination of a fire detector, wherein the fire detector detects smoke density and environmental temperature.
A sensitivity correction calculating unit that calculates a correction value of a predetermined fire discrimination level according to a dirt level of a degree of dirt or deterioration of the fire detecting unit; and a smoke density or temperature level detected by the fire detecting unit. A fire judging unit that judges a fire by comparing with a preset fire discrimination level and that gradually corrects the fire discrimination level based on the correction value from the sensitivity correction calculation unit; and a correction value from the sensitivity correction calculation unit. And a dirt level output unit for generating and outputting a dirt level according to claim 1, wherein the dirt level can be confirmed from outside. 2. As a check means for checking the stain level from outside, the stain level is transmitted by connection with an external device such as an inspection tool or by infrared communication means,
2. The fire detector according to claim 1, wherein the contamination level can be confirmed by an external device such as an inspection tool. 3. As a means for checking the contamination level from outside, when the power of the fire detector is once turned off and then turned on again, the fire detector has the contamination level only for a certain period of time after the power is turned on. The fire detector according to claim 1, wherein the fire detector can be confirmed by a lighting state of the lamp. 4. The fire sensor according to claim 2, further comprising a configuration for estimating the life of the detector based on the contamination level displayed by an inspection tool or the like and displaying the remaining time.