JPH064787A - Photoelectric separation type fire sensor - Google Patents

Abstract

PURPOSE:To automatically execute resetting by only turning on a power source by executing resetting and updating the reference light quantity, and also, rewriting and updating renewal data of a volatile storage means to the same as specific data, when the updatable data of the volatile storage means and specific data of a nonvolatile storage means are different from each other. CONSTITUTION:A nonvolatile storage means 15 always stores specific data A, B which cannot be updated, and a second volatile storage means 16 stores updatable data (a), (b) which can be stored only at the time when a power source is turned on. The specific data A, B of the nonvolatile storage means 15 are added by an adder 17, and the updatable data (a), (b) of a second nolatile storage means 16 are also added by an adder 18. A comparator 19 always compares an added value A+B and an added value (a)+(b) and outputs a signal at the time when both of them are different from each other, and a resetting circuit 20 resets a first volatile storage means 10, and also, reads out the specific data A, B of the nonvolatile storage means 15, and rewrites and updates the updatable data (a), (b) of a second volatile storage means 16 to the specific data A, B.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention comprises a light projector for projecting light and a light receiver for receiving the light.
The reference light amount stored in the volatile storage means is compared with the received light amount of the light from the projector, and a fire signal is output based on the comparison result, and the reference light amount is reset by resetting the light receiver of the receiver. The present invention relates to a photoelectric type fire detector that is updated to a value corresponding to the amount of received light.

[0002]

2. Description of the Related Art FIG. 3 is a diagram showing a conventional example of a photoelectric separation type fire detector.

A conventional photoelectric separation type fire detector 1 is for detecting a fire in a large hall such as a gymnasium, and comprises a light projector 3 for projecting light and a light receiver 2 for receiving the light. The light projector 3 and the light receiver 2 are respectively installed near the indoor ceiling with a distance of several tens of meters. The photoelectric separation-type fire sensor 1 is designed so that the light receiver 2 receives light such as infrared rays projected intermittently (for example, every 5 seconds) from the light projector 3. However, when a fire factor such as smoke is present between the light projector 3 and the light receiver 2, the amount of light emitted is attenuated in proportion to the degree of smoke density. The amount of light received by the light receiver 2 changes depending on the degree of smoke density and the like. The light receiver 2
Compares the amount of light received intermittently with a reference amount of light stored in advance in a volatile storage means (not shown) such as a RAM, and the amount of received light is 50% or less of the reference amount of light. When it becomes, for example, three consecutive times, a fire signal is output. A receiver 4 is connected to the light receiver 2,
The receiver 4 receives a fire signal from the light receiver 2 and issues an alarm.

In the photoelectric separation type fire detector 1,
At the time of installation, the optical axis is aligned and the light amount is adjusted.
That is, after the alignment of the optical axes of the light projector 3 and the light receiver 2 is completed, the power is turned on and the reset switch 5 provided on the light receiver 2 is manually pressed to receive the light from the light projector 3. Then, the amount of received light is stored as the reference amount of light in the volatile storage means to perform the reset.

By the way, when the light receiving portion of the light receiver 2 is contaminated due to aging or the like, the amount of light received by the light receiver 2 is further attenuated due to the influence of the contamination. Therefore, as the dirt of the light receiving portion progresses, the dirt does not operate normally, for example, the fire signal is output, so that the photoelectric separation type fire sensor 1 cannot be operated properly. The dirt of 2 is automatically compensated. That is, from the received light amount data in the past fixed period stored in the volatile storage means such as the RAM, the received light amount data when the smoke density is the lowest, that is, the maximum received light amount is selected, and the maximum received light amount is selected. By updating the amount as the reference light amount as shown in FIG. 4 as needed, when the light receiving amount of the light receiving device 2 is attenuated to 50% or less of the reference light amount regardless of the degree of contamination of the light receiving device 2. It is designed to output a fire signal.

[0006]

By the way, when the power supply is cut off for a long period of time after the installation of the photoelectric separation type fire sensor 1, it is stored in the volatile storage means. The reference light amount and the received light amount data are lost and the contents of the volatile storage means become uncertain, and the photoelectric separation type fire detector 1 does not operate normally even when the power is turned on again. . Therefore, the photoelectric separated fire detector 1 must be reset each time the power is turned on. However, in the conventional photoelectric separation type fire detector 1, a reset switch 5 for resetting is provided in the light receiver 2, and the light receiver 2 is installed in an extremely high place such as an indoor ceiling. Therefore, the light receiver 2 cannot be easily approached, and therefore resetting is very difficult.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a photoelectric separation type fire detector which is automatically reset only by turning on the power. To do.

[0008]

In order to solve the above problems, the present invention comprises a light projector for projecting light and a light receiver for receiving the light, the light receiver being stored in a first volatile storage means. While comparing the reference light amount and the received light amount of the light from the floodlight and outputting a fire signal according to the comparison result,
By performing a reset, in the photoelectric separation type fire detector, which is configured to update the reference light amount to a value corresponding to the light receiving amount of the light receiver at the time of resetting, non-volatile storage means for always storing specific data, A second volatile storage means for storing update data capable of updating the stored content, and further, the update data of the second volatile storage means or a calculated value of the update data and the non-volatile storage means When the data or the calculated value of the specific data are different from each other, the reset is performed to update the reference light amount, and the update data of the second volatile storage means is rewritten and updated to be the same as the specific data. And means.

[0009]

In the normal state, the update data of the second volatile storage means or the calculated value of the update data is the same as the specific data of the nonvolatile storage means or the calculated value of the specific data, When the power is turned on again after the supply has been cut off for a long period of time, the contents of the update data in the second volatile storage means are lost, and the update data or the calculated value of the update data and the specific data or Since the calculated value of the specific data becomes different, the reference light amount stored in the first volatile storage means is updated accordingly, and the update data in the second volatile storage means is updated. Is rewritten and updated in the same manner as the specific data.

[0010]

The present invention will be described below with reference to the drawings showing its embodiments.

FIG. 1 is a flow chart showing an embodiment of the present invention. FIG. 2 is a block circuit diagram of the light receiver in the embodiment of the present invention. The embodiment of the present invention has the configuration of FIG. 3 and the operation of FIG.

Photoelectric separation type fire detector 1 of the embodiment of the present invention
Is intermittently (e.g., 5
Light such as infrared rays (hereinafter referred to as "projection light") projected every second) is received by the light receiver 2 and the amount of received light becomes 50% or less of the reference amount of light, for example, three consecutive times. If there is a fire, it will output a fire signal.

In FIG. 2, the amount of light received by the photodetector 2 is converted into a voltage signal by the photodetector circuit 6, amplified by the amplifier circuit 7, and then converted into an A / D converter circuit 8.
Is converted into encoded data by.

The coded data converted by the A / D conversion circuit 8 is input to the central processing unit 9 in the next stage at any time. The central processing unit 9 is adapted to read each data from the first volatile storage means 10 such as a RAM or update each data, calculate the following data based on the coded data, The data is updated at any time, and the reference light amount Mref is calculated and updated. (1) The encoded data X input every 5 seconds. (2) A plurality of the coded data X obtained within one hour
Maximum value Y at. (3) Maximum value M0 among the plurality of maximum values Y obtained within 24 hours on the day. (4) Maximum value M1 of the plurality of maximum values Y obtained in the previous 24 hours. (5) A plurality of the maximum values Y obtained in 24 hours two days before
The maximum value of M2. (6) A plurality of the maximum values Y obtained in 24 hours three days before
The maximum value of M3. (7) A plurality of the maximum values Y obtained in 24 hours 4 days before
The maximum value of M4. (8) A plurality of the maximum values Y obtained 24 hours before 5 days
The maximum value of M5. (9) A plurality of the maximum values Y obtained in 24 hours 6 days before
Maximum value of M6. (10) A reference light amount Mref which is the maximum value among the maximum values M0 to M6. In this way, the maximum value is calculated from the received light amount data obtained in the past week, and the maximum value is updated as the reference light amount Mref. The coded data X and the maximum value Y are updated every 5 seconds, the maximum value M0 is updated every hour, and the maximum values M1 to M6 and the maximum value M are updated.
The ref is updated every 24 hours. In addition, the maximum values M0 to M6 are M5 → M6, M4 every one day.
→ M5, M3 → M4, M2 → M3, M1 → M2, M0 →
M1 and M0 → Y are sequentially shifted and updated, and then the maximum value among the maximum values M0 to M6 is calculated, and the maximum value is used as the reference light amount Mref.
To update as.

Reference numeral 11 is a divider, and the coded data X and the reference light amount Mref from the first volatile storage means 10 are used.
And are read out, and the coded data X is divided by the reference light amount Mref. As a result, the ratio of the current received light amount to the reference light amount Mref is calculated. Reference numeral 13 is a comparison circuit, which stores the data (0 to 1) calculated by the divider and the ROM.
The fire judgment value L (for example, 0.5) stored in is compared, and a signal is output when the data calculated by the divider falls below the fire judgment value L. A fire signal output circuit 14 receives a signal output from the comparison circuit 13 in the preceding stage, counts the signal output, and outputs a fire signal to a receiver (not shown) when the number of counts reaches three times. Output.

The initialization block 30 includes a nonvolatile storage means 15 such as a ROM and a second volatile storage means 16 such as a RAM.
And have. The non-volatile storage means 15 always stores two pieces of specific data A and B that cannot be updated regardless of the presence / absence of a power source. The second volatile storage means 16 stores two pieces of update data a and b whose contents can be updated only when the power is turned on. When the power is turned off for a long time, the contents of the two update data a and b disappear and become indeterminate. Two specific data A and B (for example, A = 10101010, B = 0) of the non-volatile storage means 15.
1010101) is added by the adder 17 to obtain the added value A + B (for example, A + B = 11111111).
Is output as. Similarly, the second volatile storage means 1
The two update data a and b of 6 are also added by the adder 18 and output as the added value a + b. Reference numeral 19 denotes a comparison circuit, which constantly compares the added value A + B and the added value a + b, and outputs a signal only when they are different from each other. Reference numeral 20 denotes a reset circuit which is a reset updating means, which receives the signal output from the comparison circuit 19 at the previous stage and resets the first volatile storage means to the initial state, and at the same time, the nonvolatile storage means 15 One specific data A,
B is read, and the two update data a and b in the second volatile storage means 16 are rewritten and updated to the specific data A and B, respectively.

The photoelectric separation type fire detector 1 having the above structure is
It is designed to operate at the same time when the power is turned on,
At that time, the initialization block 30 operates as shown in FIG. In the power-on state, as shown in step S2, the added value A + B of the two specific data A and B in the non-volatile storage means 15 and the second volatile storage means 16 are set.
Are compared with the addition value a + b of the two update data a and b, but since the addition value A + B and the addition value a + b are the same when the power is on, the step S2
Is repeated and the two are constantly compared. If the power supply is cut off here, the photoelectric separation type fire detector 1 stops its operation. Further, when the power is turned on again as shown in step S1 after the power is turned off for a long time, the contents of the two update data a and b of the second volatile storage means 16 are lost and uncertain. Therefore, in step S2, the additional value A + B and the additional value a +
Since the value b and the value b are different from each other, the contents of the first volatile memory device 10 are reset as shown in step S3. As a result, as shown in step S4, the amount of received light at the time of reset is updated in the first volatile storage device 10 as the reference amount of light Mref. Further, as shown in step S5, the two update data a and b of the second volatile storage means 16 are rewritten and updated to the specific data A and B, respectively,
Then, the process returns to step S2, and the comparison between the added value A + B and the added value a + b is performed again.

The number of specific data in the non-volatile storage means 15 or the number of updated data in the second volatile storage means 16 does not matter. That is, the specific data and the update data may each be configured one by one, or may be configured by a plurality of specific data and a plurality of update data, and the corresponding specific data and update data may be compared with each other. Good.

[0019]

As described above, the present invention comprises a light projector for projecting light and a light receiver for receiving the light, wherein the light receiver has a reference light amount stored in the first volatile storage means, In the photoelectric separation type fire detector, which compares the received light amount of the light from the floodlight and outputs a fire signal according to the comparison result, and updates the reference light amount by resetting, one or more specific data. A non-volatile storage means for constantly storing the data, a second volatile storage means for storing one or a plurality of update data whose storage contents can be updated, update data of the second volatile storage means, or calculation of the update data. When the value and the specific data of the non-volatile storage means or the calculated value of the specific data are different from each other, the reset is performed, and the update data of the second volatile storage means is
It is characterized in that it has a reset update means for rewriting and updating the same as the specific data, and normally, the update data of the second volatile storage means or the operation value of the update data is the nonvolatile data. Although it is the same as the specific data of the storage means or the calculated value of the specific data, when the power is turned on again after the power supply is cut off for a long period of time due to construction or the like, the contents of the update data of the second volatile storage means Disappears and the updated data or the calculated value of the updated data becomes different from the specific data or the calculated value of the specific data. Therefore, resetting is performed and the second volatile storage means is updated. Since the data is rewritten and updated in the same way as the specific data, it can be automatically reset by simply turning on the power, and in the event of a power failure, etc. You can save the trouble of manually pressing the reset switch at high places to reset it, and the maintenance becomes very easy.

[Brief description of drawings]

FIG. 1 is a flow chart showing an embodiment of the present invention.

FIG. 2 is a block circuit diagram showing an embodiment of the present invention.

FIG. 3 is a diagram showing an example of the present invention and a conventional example.

FIG. 4 is a diagram showing the operation of an embodiment of the present invention and a conventional example.

[Explanation of symbols]

 10 First Volatile Storage Means 15 Nonvolatile Storage Means 16 Second Volatile Storage Means 19 Comparison Circuit 20 Reset Updating Means Mref Reference Light Quantity a Update Data b Update Data A Specific Data B Specific Data

Claims (1)

[Claims] 1. A light emitter for projecting light and a light receiver for receiving the light, wherein the light receiver has a reference light amount stored in a first volatile storage means and a light receiving amount of the light from the light projector. And a fire signal is output according to the comparison result, and a reset is performed to update the reference light amount to a value corresponding to the light receiving amount of the light receiver at the time of resetting In the sensor, a non-volatile storage unit that constantly stores specific data, a second volatile storage unit that stores update data whose storage content can be updated, and update data of the second volatile storage unit or the update data. And the specific data of the non-volatile storage means or the calculated value of the specific data are different from each other, the reset is performed to update the reference light amount, and the second volatile storage is performed. A photoelectric separated fire detector, characterized in that it has reset update means for rewriting and updating the update data of the means in the same manner as the specific data.