JP2979496B2 - Sensitivity adjustment method of differential spot type fire detector and sensitivity adjustment device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and a device for adjusting the sensitivity of a fire detector for adjusting the sensitivity of a differential spot type fire detector used in a fire alarm system.
More specifically, in the present invention, the interval between the contacts of the differential spot-type fire detector arranged in the depressurized closed tank is set to be wider than the normal position in advance, and in this state, the contact is set in an atmosphere having a predetermined depressurized characteristic. Exposure, measuring the operation time until the fire detector operates in such a reduced-pressure atmosphere, obtaining the contact interval to the best point based on the operation time, and adjusting the contact interval to the interval. The present invention relates to a sensitivity adjustment method for a spot-type fire detector and a sensitivity adjustment device for realizing the sensitivity adjustment method for the fire detector.

[0002]

2. Description of the Related Art A differential spot-type fire detector of this type is known as a device which detects a case where a temperature rise rate is equal to or higher than a predetermined value and outputs an operation signal (contact ON). FIG.
FIG. 2 is a sectional view showing the differential spot type fire detector described above. FIG. 9 is a plan view showing the fire detector. In these figures, a differential spot type fire detector 101 is shown.
For example, a chamber 102 having a U-shaped cross section, a diaphragm mounting frame 103 provided on the upper portion of the U-shaped cross section of the chamber 102, a diaphragm 104 fixed to the diaphragm mounting frame 103, and the chamber 10
2. Diaphragm mounting frame 103 and diaphragm 104
A leak resistor 106 for communicating the enclosed air chamber 105 with the outside world with a predetermined air resistance value, a base 107 on which the chamber or the like is mounted, and the diaphragm 1
04, a fixed contact 109 fixed to the base 107 side, and a fixed contact 109 screwed to the base 107 to move the fixed contact 109.
Adjusting screw 110 for adjusting the distance between the contact and the fixed contact 109
And terminals 111 and 112 electrically connected to the contacts 108 and 109.

In the differential spot-type fire detector 101 having such a structure, when the temperature of the outside increases, the inside of the air chamber 105 surrounded by the chamber 102, the diaphragm mounting frame 103 and the diaphragm 104 is increased. The air expands due to the heat and leaks from the leak resistor 106. Therefore, when the temperature rise rate is equal to or less than the predetermined temperature increase rate, the air expanded inside the air chamber 105 has a
Since it leaks from 06 to the outside, there is no change in the diaphragm 104, and neither of the contacts 108, 109 is closed. However, when the temperature rise rate of the outside reaches a predetermined value or more, the air in the air chamber 105 of the fire detector 101 cannot leak from the leak resistor 106, so that the diaphragm 104 is displaced and the movable contact 108
Contacts the fixed contact 109 and outputs an operation signal (contact ON).

[0004] Such a differential spot type fire detector 1
01 is conventionally adjusted when the leak resistance is 10
9 is removed, an air injection pipe (not shown) is connected to the leak resistance mounting portion, and a fixed amount of air is injected into the air chamber 105 in a sealed state.
The movable contact 108 and the fixed contact 109 are closed so that the contact 109 is closed.
Are adjusted by the contact adjusting screw 110. And
After the adjustment, in a completed state in which the leak resistor 106 is mounted on the leak resistor mounting portion, a linear ascending test, a step airflow test, and the like were performed. In this stage airflow test, the fire detector 101 is exposed to an airflow having a temperature set at a predetermined value higher than room temperature and a predetermined wind speed, and if the fire detector 101 is operated within a predetermined time range after the exposure, the sensitivity is determined to be normal.

On the other hand, there has been proposed a method of measuring the amount of displacement of the diaphragm without the trouble of connecting an air injection pipe to the leak resistance mounting portion of the leak resistor 106 (see Japanese Patent Publication No. 2-116997). In this measuring method, a fire detector is placed in a reduced-pressure sealed tank, the pressure in the reduced-pressure sealed tank is reduced, and the displacement of the diaphragm of the fire detector at that time is measured with a displacement meter. According to this measuring method, the connection of the air injection pipe is not required.

[0006]

As described above, in the sensitivity adjustment method of the conventional differential spot type fire detector, the sensitivity adjustment is performed in a state where the leak resistance is not taken into consideration. Since the sensitivity adjustment is not performed in the state, there is a disadvantage that the sensitivity adjustment is not complete.

In the sensitivity adjusting method of the conventional differential spot type fire detector, air is injected from a leak resistance mounting portion before the leak resistance is mounted.
There is a drawback that it takes time to connect the air injection pipe to the mounting part of the leak resistance.

Further, in the above-described sensitivity adjustment method of the differential spot type fire detector, after the adjustment, it is necessary to perform a linear ascending test and a staircase airflow test, which require a long test time for one time. In order to adjust the sensitivity of the detector, there is a disadvantage that efficiency is low.

In addition, in the method of measuring the displacement of the diaphragm of the fire detector by disposing the fire detector in the decompression chamber, the displacement of the diaphragm is simply detected by the displacement meter, so that the sensitivity is adjusted. In addition, an expensive displacement meter capable of reliably measuring displacement is required, and the number of devices is increased.

An object of the present invention is to provide a method and an apparatus for adjusting the sensitivity of a differential spot-type fire sensor, which can solve the above-mentioned drawbacks and can execute the sensitivity of a large number of fire detectors efficiently in a short time. The purpose is.

[0011]

In order to achieve the above object, a method for adjusting the sensitivity of a differential spot-type fire detector according to the present invention is directed to a method for adjusting the sensitivity of a differential spot-type fire detector. The contact interval of the differential spot type fire detector is set to a predetermined position which is preliminarily widened from the normal position, and the fire detector in this state is exposed to an atmosphere where the pressure is reduced according to a predetermined pressure reduction characteristic. The operating time until the fire detector operates is measured, the contact interval of the fire detector up to the best point is determined based on the operating time, and the contact interval of the fire sensor is adjusted to the determined contact interval. It is characterized by the following.

The decompression characteristic is characterized in that the pressure is reduced by a rapid change from the start of decompression to a predetermined pressure reduction value, and the pressure is reduced by a slow change when the pressure exceeds the predetermined pressure reduction value. is there. When the measured operation time is not within a predetermined time range, the fire detector is determined to be defective.

Further, the adjustment of the contact interval of the fire detector is characterized in that the contact adjustment screw of the fire detector is screwed in until the determined contact interval is reached.
In order to achieve the above object, a sensitivity adjustment device for a differential spot-type fire detector according to the present invention is a sensitivity adjustment device for a fire sensor that adjusts the sensitivity of a differential spot-type fire detector. A closed tank for adjustment capable of containing the sensor to form an atmosphere having a predetermined decompression characteristic, an exhaust system for exhausting air in the closed tank for adjustment in response to an exhaust drive control signal, and a closed tank for adjustment. A contact screw adjusting device for rotating a contact adjusting screw of the placed fire detector in accordance with a screw rotation drive control signal; and an operation signal from a fire detector placed in the closed tank for adjustment, taking in the depressurized atmosphere. Measuring the operation time until the fire detector operates within the range, obtaining the contact interval of the fire sensor up to the best point based on the operation time, and determining the contact interval of the fire sensor in the obtained contact interval. Tonality Outputs the screw rotation drive control signal to be and is characterized by comprising anda adjustment control unit that outputs an exhaust driving signal to a predetermined reduced pressure characteristics.

Here, the adjustment control device reduces the pressure by a rapid change from the start of the pressure reduction to a predetermined pressure reduction value, and reduces the pressure by a slow change when the pressure reduction value exceeds the predetermined pressure reduction value. A control signal is formed. Further, the adjustment control device includes:
When the measured operation time is not within a predetermined time range, the fire detector is determined to be defective.

[0015]

In the sensitivity adjusting method of the differential spot type fire detector according to the present invention, the operation time at the time of decompression when the contact adjusting screw of the fire detector is lifted by a predetermined amount is measured, and the fire detector is originally intended. Is normal, there is a predetermined relationship between the proper position of the contact adjustment screw and the position of the contact adjustment screw raised by a predetermined amount. The correction displacement of the adjusting screw is determined. By adjusting the contact adjusting screw of the fire detector according to the correction displacement amount thus obtained, a fire detector whose sensitivity has been accurately adjusted can be obtained.

[0016] The decompression characteristics are as follows:
The measurement time can be reduced by slowly reducing the pressure when the specified pressure reduction value is reached, and the measurement time can be extended by setting the slower decompression characteristic to the range that should be measured. Becomes possible. Further, since the operation time is measured, it can be determined that the product is non-defective when the measured operation time is within the range of the normal operation time.

In addition, in the adjustment of the contact interval of the fire detector, only the direction in which the contact adjustment screw of the fire detector is screwed in until the obtained contact interval is reached can be absorbed.

In the sensitivity adjusting device for a differential spot-type fire detector according to the present invention, the operating time during depressurization when the contact adjusting screw of the fire detector is lifted by a predetermined amount is configured as described above. It can be measured, and when the fire detector is normally assumed to be normal, it utilizes the fact that there is a predetermined relationship between the proper position of the contact adjustment screw and the position where the contact adjustment screw is raised by a predetermined amount. The adjustment displacement of the contact adjustment screw up to the appropriate position can be obtained by the adjustment control device, and the contact adjustment screw of the fire detector can be adjusted by the contact screw adjustment device according to the obtained correction displacement. It is possible to obtain a fire detector whose sensitivity is accurately adjusted.

Further, the adjustment control device reduces the pressure by a rapid change from the start of the pressure reduction to a predetermined pressure reduction value, and reduces the pressure with a slow change when the pressure reduction value exceeds the predetermined pressure reduction value. So that it forms a signal,
It is possible to obtain a desired pressure reduction characteristic. Further, the adjustment control device is configured to determine that the fire detector is defective when the measured operation time is not within the predetermined time range, so that the quality determination can be performed at a high speed.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the illustrated embodiments. FIG. 1 is an overall configuration diagram showing a sensitivity adjustment device for realizing a sensitivity adjustment method for a differential spot type fire detector according to the present invention.

The sensitivity adjusting device 11 shown in FIG. 1 is roughly divided into an adjusting closed tank 12, an exhaust system 13, a contact screw adjusting device 14, and a fire detector placed in the adjusting closed tank 12. An adjustment control device 1 that performs a predetermined calculation based on the operation signal from the exhaust system 101 and the detection signal from the exhaust system 13 to control the operations of the exhaust system 13 and the contact screw adjustment device 14
5

The adjusting closed tank 12 has a closed rectangular parallelepiped shape, and a fire detector mounting table 16 is provided in a portion of the rectangular parallelepiped at about the upper third in the figure. The fire detector mounting table 16 is used for the chamber 1 of the fire detector 101.
A circular hole 17 into which a hole 02 is inserted is formed. A tank lid 19 is detachable on the upper part of the closed tank 12 for adjustment. When the tank lid 19 is attached to the closed tank 12 for adjustment, the inside of the closed tank 12 for adjustment is sealed from the outside. It is set to be in a state of being left. A pressure gauge 18 is provided inside the closed tank 12 for adjustment.

The tank lid 19 is provided with a contact screw adjusting device 14, a screw driving unit 20 driven by the contact screw adjusting device 14, and lead terminals 21 and 22. When the fire detector 101 is placed on the fire detector mounting table 16 of the closed tank for adjustment 12 and the tank lid 19 is mounted on the upper part of the closed tank 12 for adjustment, the screw drive unit 20 is turned on by the fire detector. 101 contact adjustment screw 11
0, and the lead terminals 21, 22 are connected to the terminals 111, 112 of the fire detector 101. Although not shown, the contact screw adjusting device 14 may be constituted by, for example, a step motor.

The exhaust system 13 is configured as follows. The adjustment closed tank 12 is connected to an exhaust cylinder 25 via a pipe 24 provided with an on / off solenoid valve 23 in the middle. Inside the exhaust cylinder 25, a syringe piston 26 is provided slidably in the horizontal direction in the figure. The syringe piston 26 is connected to a movable portion 29 of a syringe piston driving device 28 by an operating punch 27. The syringe piston driving device 28 rotatably arranges a bar screw 31 on a fixed base 30 having a concave shape as viewed from one side, and attaches the bar screw 31 to, for example, a step motor 32.
By rotating the movable portion 29 forward and backward, the movable portion 29 can be moved in the horizontal direction in the figure. In addition, the syringe piston driving device 28 is provided with a piston position detection unit 33 that detects the position of the movable unit 29. The piston position detection unit 33 includes, for example, optical sensors 34a, 34b, 34c, 34d, and 34e in which a reflector or the like (not shown) is fixed to the movable unit 29 and a light emitting diode and a photo sensor are integrally provided. It is arranged and arranged at a predetermined position.

The lead terminals 21 and 22 and the piston position detecting section 33 are electrically connected to the adjustment control device 15 so that an operation signal of the fire detector 101 and a piston position detecting signal of the piston position detecting section 33 are transmitted. Adjustment control device 1
5 is input. The adjustment control device 15 is provided with a timer (not shown) so that the operation time can be measured. Further, the electromagnetic valve 23 and the motor 32 of the syringe piston driving device 28 are electrically connected to the adjustment control device 15, and the adjustment control device 15 controls the electromagnetic valve 23 to be on / off to shut off the air from the atmosphere. In addition to the open state, the motor 32 of the syringe piston driving device 28 can be rotated forward and backward.

FIG. 2 is a block diagram showing the above-described sensitivity adjusting device, and is a diagram showing the configuration of the adjustment control device in a little more detail. The adjustment control device 15 includes a central processing unit 50, two interfaces 51 and 52 connected to the central processing unit 50, and a timer 53 controlled by the central processing unit 50 to measure an operation time and the like. Although not shown, the central processing unit 50 includes a processing unit that executes various arithmetic processing, a ROM that stores a predetermined program, a RAM that stores predetermined data, and the like.
The fire detector 101 is connected to an interface 51 of the adjustment controller 15 via lead terminals 21 and 22 not shown in FIG. The piston position detector 33
Are also connected to the interface 51. Accordingly, the operation signal from the fire detector 101 and the position detection signal of the piston position detection unit 33 are input to the central processing unit 50 via the interface 51. The interface 52 is connected to the solenoid valve 23, the motor 32 of the syringe piston driving device 28, and the contact screw adjusting device 14.

Before explaining the operation of the sensitivity adjusting apparatus for a differential spot-type fire detector, the reason why the sensitivity adjusting method for the differential spot-type fire detector can be realized will be described.

First, FIG. 3 shows the fire detector 1 during the stair test.
FIG. 11 is a characteristic diagram showing a relationship between the pressure Y ₁ (vertical axis) inside the air chamber 105 and the staircase test operation time T ₁ (horizontal axis). Internal pressure Y ₁ [mmH ₂ O] of air chamber 105 of fire detector 101
It is intended to have a relationship that is proportional to the staircase test operation time T ₁ (second), when the predetermined time B _t has elapsed from a certain time A _t, made from pressure A _p to B _p. This allows Y
₁ is

(Equation 1) Becomes

FIG. 4 shows the air chamber 105 of the fire detector 101.
5 is a characteristic diagram showing a relationship between the internal pressure Y ₂ (vertical axis) and the displacement U of the contact adjusting screw 110 (horizontal axis). Fire detector 1
01 (inspection pressure) Y ₂ [mmH
₂ O] are those having a relationship proportional to the displacement of the contact adjustment screw 110 mm and can be detected by the pressure C _p when a certain displacement C _d, the pressure D _p at a certain displacement D _d It can be detected. Therefore, the detection pressure Y
₂ is

(Equation 2) Becomes

FIG. 5 shows the pressure P in the closed tank 12 for adjustment.
a, the internal pressure Pb of the air chamber 105 of the fire detector 101 is shown, the differential pressure Y ₃ between the two pressures Pa and Pb (vertical axis), and the operation time T ₂ of the fire detector 101 when the pressure is reduced (horizontal axis). FIG. 4 is a characteristic diagram showing a relationship between Adjustable sealed tank 1
When the pressure Pa in the 2 Yuku sharply down to the time G _t of FIG. 5, Yuku also decrease the pressure Pb of the air chamber 105 of the fire detector 101 with a decrease in the pressure. Further, when Yuku is lowered slowly pressure Pa of the adjustment sealed tank 12 from time G _t, fire detector 101 of the air chamber along with this 1
It can be seen that the pressure Pb of 05 also decreases. In addition, the differential pressure Y ₃ [mmH ₂ O] between the two pressures Pa and Pb also becomes a steep part in the first half of the time Gt and separates into a part having a gentle slope after the time Gt. Then, after time Gt, both pressure Pa, the pressure difference Y ₃ of Pb [mmH ₂ O] is assumed to have a relationship that is proportional to the operation time T ₂ of the vacuum during fire at certain operating time E _t sometimes pressure E _p sensor 101 is operated, it will operate at a pressure F _p when a certain operation time F _t. Therefore, the detected differential pressure Y ₃ is

(Equation 3) Becomes

Further, the relationship between the pressure reduction during the operation time T ₂ and stepped test operation time T ₁ is formula 1 = Equation 3 from Y ₁ = Y ₃
Becomes

(Equation 4) Becomes

Further, the displacement amount U of the contact adjusting screw 110
And the operation time T ₂ at the time of depressurization is obtained from Y ₂ = Y ₃ from Equation 2 = Equation 3.

(Equation 5) Becomes

Step test (for example, 30 deg, 85 cm / sec)
The center value is set to be 15 seconds when the bandwidth of the operation time is set to 12 to 18 seconds. Therefore, the operation time (T ₁ ) in the stair test is = 15.
In seconds, the decompression operating time T ₁₅ (T ₂ ) is given by Equation 4
By

(Equation 6) Becomes Similarly, the operation time T ₁₈ at the time of decompression in 18 seconds.
Is

(Equation 7) Becomes Displacement U _15, U ₁₈ contacts the adjustment screw 110 when the above-mentioned operation time T _15, T _18, from Equation 5,

(Equation 8)

(Equation 9) Becomes

Therefore, first, the contact adjusting screw 110 is set to the zero point (when the pressure is within the atmospheric pressure, the contact adjusting screw 110 is lifted from the point where the terminals 111 and 112 are turned on to the point where the terminals are turned off, and the point is set to 0 mm). from, keep lifting up to U _18. The decompression time operating time of this time is T _18.

FIG. 6 is a characteristic diagram for explaining the operation for obtaining the correction amount, in which the horizontal axis represents the operation time T ₂ and the vertical axis represents the displacement U of the contact adjustment screw 110. To adjust the vacuum during operation time T _15, the contact adjustment screw 110
Let ΔU be the corrected displacement of

(Equation 10) Will be required. Therefore, the displacement X of the contact adjustment screw 110 when corrected is

[Equation 11] Can be obtained as

Generally, when the operation time at the time of pressure reduction when lifting up to U ₁₈ (mm) is δ (second), the contact adjusting screw 110 is adjusted to adjust the operation time at pressure reduction to T ₁₅ (second).
Let ΔU be the corrected displacement of

(Equation 12) Becomes

As described above, the contact adjusting screw 110 of the fire detector 101 is returned to a predetermined position.
01 is placed in the closed tank 12 for adjustment and the pressure is reduced. When the fire detector 101 is activated at the above-mentioned position, when the operation time is within the normal operation time range (ΔC in FIG. 5), The correction amount X is obtained from the above formulas 11 and 12, and the contact adjustment screw 110 of the fire detector 101 is screwed by this X, so that accurate sensitivity adjustment of the fire detector including the leak resistor 106 can be performed in a short time. Can be performed efficiently.

Next, the above embodiment will be described with reference to FIGS. 1 and 2.
The operation will be described with reference to FIGS. FIG. 7 is a flowchart for explaining a sensitivity adjustment method of the differential spot type fire detector executed by the apparatus of FIGS. 1 and 2.

First, the tank cover 19 is opened, and the fire detector 101 is placed at a predetermined position of the fire detector mounting table 16 in the closed tank for adjustment 12. Next, the tank lid 19 is attached to the adjustment closed tank 12. As a result, the terminals 111 and 112 of the fire detector 101 are connected to the lead terminals 21 and
The screw drive unit 20 contacts the contact adjusting screw 110.

When such a state is reached, the central processing unit 50 of the adjustment control device 15 supplies a drive signal to the contact screw adjustment device 14 via the interface 52.
Thereby, the contact screw adjusting device 14 rotates according to the drive signal, and pulls up the contact adjusting screw 110 of the fire detector 101 in the adjustment closed tank 12 to a predetermined position (for example, U ₁₈ ) (Step 201).

Next, the central processing unit 5 of the adjustment control unit 15
In the case of 0, the electromagnetic valve 23 is closed to shut off from the atmosphere, and the timer 53 for measuring the elapsed time is operated (step 20).
2). Next, the central processing unit 50 supplies a high-speed rotation signal to the motor 32 of the syringe piston driving device 28 via the interface 53. As a result, the motor 32 rotates at a high speed. During this time, since the position of the syringe piston 26 is detected by the piston position detecting unit 33, the rotation of the motor 32 is controlled based on the detection signal from the piston position detecting unit 33. As a result, the movable portion 29 moves to the right side in the drawing at a high speed, and accordingly, the syringe piston 26 is withdrawn at a high speed. By executing this from time 0 to time Gt, the pressure is rapidly reduced for a predetermined time (step 203). Therefore, the fire detector 101 placed in the closed tank for adjustment 12 is placed under the rapid pressure-reducing characteristics.

Then, after time Gt, the central processing unit 50 of the adjustment control device 15 outputs a drive signal for rotating the motor 32 of the syringe piston driving device 28 at a low speed so that the syringe piston 26 is pulled out at a low speed. As a result, the syringe piston 26 is withdrawn so as to have a very gentle pressure reduction characteristic per unit time (step 204). Therefore, the fire detector 101 which is arranged on the adjustment sealed tank 12 will be exposed to a vacuum of a very gentle slope per unit time as indicated by the characteristic Y ₃ in FIG. In addition, it is checked whether or not the pressure in the adjustment closed tank 12 is changing according to Pa in FIG. 5 by a measurement signal from the pressure gauge 18.

Then, the central processing unit 50 of the adjustment control device 15 starts to determine whether or not an operation signal is input from the fire detector 101 in such a state within a predetermined time (step 205; NO, Step 206, Step 2
07; NO). That is, when an operation signal is not input from the fire detector 101 placed in the closed tank for adjustment 12 and placed under the pressure-reducing characteristics (step 205; NO), the central processing unit 50 sets the timer. The counting time of 53 (step 206) is taken, and it is determined whether or not the counting time (the elapsed time from the time Gt) has passed a predetermined time zone ΔC (step 207). Sometimes (step 207; N
O), it is determined again whether there is an operation signal from the fire detector 101 (step 205).

Here, when an operation signal is input from the fire detector 101 placed in the adjustment closed tank 12 to the central processing unit 50 (step 205; YES), the central processing unit 50 , The operation time _Ft is taken in, and the solenoid valve 18 is opened to return to the atmospheric pressure (step 20).
8), and it determines whether the operation time F _t is within a range of a predetermined time in the [Delta] C (step 209).

Then, the central processing unit 50 sets the timer 53 when the operation signal of the fire detector 101 is input.
Based on; (YES step 209), (corresponding to decompression operation time δ in the description of the equation 12) the operating time F _t in the case where operation time F _t was within the range of a predetermined time in ΔC from Using the above equation 12, the fire detector 10
The correction displacement amount ΔU of the first contact adjustment screw 110 is calculated (step 210). The corrected displacement amount ΔU of the contact adjusting screw 110 of the fire detector 101 determined in this manner.
, The central processing unit 50 outputs a rotation drive signal to the contact screw adjusting device 14 (step 211), and ends the processing. As a result, the screw driving unit 20 of the contact screw adjusting device 14 rotates according to the rotation drive signal, and the contact adjusting screw 110 of the fire detector 101 placed in the adjusting closed tank 12 is moved by a predetermined correction displacement. Rotate by the amount ΔU. As a result, the fixed contact 109 is
, And is adjusted to an accurate center position (for example, the center position U ₁₅ , which corresponds to a position that operates at the time Et or t ₁₅ in FIG. 5). This position is, as described above, the fire detector 1
Since it includes the action of the leak resistance 106 of 01, the fire detector 101 operates accurately when the pressure difference between the inside and outside of the air chamber 105 of the fire detector 101 reaches the pressure.

On the other hand, the central processing unit 50 is placed in the closed tank for adjustment 12 and when no operation signal is input from the fire detector 101 placed under the reduced pressure characteristic (step 205; NO) ), The counting time of the timer 53 is taken in (step 206), and it is determined whether or not the counting time (elapsed time from the time Gt) has passed a predetermined time period ΔC (step 207).
Is passed (step 207; YES), the fire detector 101 is determined to be defective (step 212), and the process is terminated.

An operation signal from the fire detector 101 mounted in the adjustment closed tank 12 is transmitted to the central processing unit 5.
When input to 0 (step 205; YES), the central processing unit 50 takes in the operation time F _t from the timer 53 (step 208), the operation time F _t is not in the range of a predetermined time in ΔC Sometimes (Step 20
9; NO), as described above, the fire detector 101 is determined to be defective (step 212), and the process ends.

As described above, in this embodiment, the fire detector 101 is housed in the closed tank 12 for adjustment, and the contact adjusting screw 110 of the fire detector 101 is rotated to fix the fixed contact 10.
9 and the movable contact 108 are set at a predetermined position which is widened (pulled up) by a predetermined range from the normal contact distance in advance, and in this state, the inside of the adjustment closed tank 12 is depressurized with a predetermined depressurization characteristic. The elapsed time when an operation signal is issued from the fire detector 101 is measured below, and a corrected displacement amount that is a contact interval that becomes an optimal operation time is obtained from the elapsed time, and the contact interval is moved by the corrected displacement amount. Therefore, the operation of the fire detector 101 is controlled by the leak resistance 106.
Thus, the fire detector 101 that operates accurately can be obtained.

In the above embodiment, the fire detector 101
The contact adjusting screw 110 can be adjusted by the contact screw adjusting device 14 and the exhaust system 13 that can make the inside of the adjusting closed tank 12 have a predetermined decompression characteristic. Can be efficiently adjusted in a short time. At this time, the fire detector 1
In the adjustment of the contact interval of No. 01, the contact adjusting screw 110 of the fire detector 101 is screwed (turned in only one direction) until the determined contact interval is reached. Backlash (play) with the adjusting screw 110 can be absorbed, and accurate adjustment can be performed.

Further, in the present embodiment, the predetermined pressure reducing characteristic is rapidly reduced from the start of the adjustment until the predetermined time Gt, and the pressure is reduced slowly after the predetermined time Gt.
The sensitivity of the fire detector 101 can be adjusted accurately and in a short time.

In addition, in this embodiment, the fire detector 101
If the operation time of the fire detector is not within the predetermined range, the fire detector 1
01 can be determined to be defective.
01 can be tested and adjusted in a short time.

In the above embodiment, the fire detector 1
01, the elapsed time when the operation signal is issued is measured, the corrected displacement amount that is the contact interval that becomes the optimum operation time is obtained from the elapsed time, and the contact screw adjusting device 14 is operated based on the corrected displacement amount. Therefore, the sensitivity of the fire detector 101 can be adjusted, so that the sensitivity can be adjusted efficiently in a short time.

[0053]

According to the sensitivity adjusting method of the differential spot type fire detector according to the first aspect of the present invention, the contact interval of the differential spot type fire detector is set to a predetermined position which is wider than a normal position. Setting, exposing the fire sensor in the state to an atmosphere that decompresses according to a predetermined decompression characteristic, measuring an operation time until the fire sensor operates in the decompression atmosphere,
The contact interval of the fire detector up to the best point is obtained based on the operation time, and the contact interval of the fire detector is adjusted to the obtained contact interval. A fire detector that includes the function and operates correctly can be obtained.

According to the second aspect of the present invention, the pressure reduction characteristic is reduced by a sudden change from the start of pressure reduction to a predetermined pressure reduction value, and is reduced by a slow change when the pressure reduction characteristic exceeds the predetermined pressure reduction value. Therefore, the measurement can be speeded up, and accurate measurement can be performed because the measurement point has a slow change.

According to the third aspect of the present invention, when the measured operation time is not within the predetermined time range, the fire detector is determined to be defective, so that the quality can be quickly determined.

According to the fourth aspect of the present invention, the adjustment of the contact interval of the fire detector is performed in one direction since the contact adjustment screw of the fire detector is screwed in until the determined contact interval is reached. The error of the screwing device can be absorbed.

According to the fifth aspect of the present invention, it is possible to measure the decompression operation time when the contact adjusting screw of the fire detector is lifted by a predetermined amount, and that the fire detector is originally normal. In addition, by utilizing the fact that there is a predetermined relationship between the appropriate position of the contact adjustment screw and the position of the contact adjustment screw raised by a predetermined amount, the adjustment control device calculates the correction displacement amount of the contact adjustment screw to the appropriate position using the adjustment control device. It can be obtained, and the contact adjusting screw of the fire sensor can be adjusted by the contact screw adjusting device according to the obtained amount of correction displacement, so that a fire sensor with accurately adjusted sensitivity can be efficiently obtained in a short time. be able to.

In the invention according to claim 6, the pressure of the adjustment control device is reduced by a rapid change from the start of pressure reduction to a predetermined pressure reduction value, and the pressure is reduced by a slow change when the pressure reduction value exceeds the predetermined pressure reduction value. Since the exhaust drive control signal is generated so that the pressure-reducing characteristics are reduced, the pressure-reducing characteristics can be arbitrarily determined.

Further, according to the present invention, when the measured operation time is not within a predetermined time range, the fire detector is determined to be defective. And can do it accurately.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram showing a sensitivity adjustment device that realizes a sensitivity adjustment method for a differential spot-type fire detector according to the present invention.

FIG. 2 is a block diagram showing a sensitivity adjusting device of the embodiment.

FIG. 3 is a characteristic diagram showing the relationship between the pressure inside the air chamber of the fire detector and the operating time of the stair test during the stair test according to the present invention.

FIG. 4 is a characteristic diagram showing a relationship between an internal pressure of an air chamber of a fire detector and a displacement amount of a contact adjustment screw according to the present invention.

FIG. 5 is a characteristic diagram showing the relationship between the pressure in the closed tank for adjustment, the internal pressure of the air chamber of the fire detector, and the differential pressure between the two pressures and the operation time of the fire detector when the pressure is reduced according to the present invention. is there.

FIG. 6 is a characteristic diagram for explaining an operation for obtaining a correction amount of a contact adjustment screw of a fire detector according to the present invention.

FIG. 7 is a flowchart for explaining a sensitivity adjustment method of the differential spot type fire detector executed by the apparatus of the embodiment.

FIG. 8 is a sectional view showing a differential spot-type fire detector.

FIG. 9 is a plan view showing the fire detector.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Sensitivity adjusting device of differential spot type fire detector 12 Sealing tank for adjustment 13 Exhaust system 14 Contact screw adjusting device 15 Adjustment control device 19 Tank lid 20 Screw driving unit 21 Lead terminal 22 Lead terminal 28 Syringe piston driving device 101 Fire detector 102 Chamber 103 Diaphragm mounting frame 104 Diaphragm 105 Air chamber 106 Leakage resistance

Continuation of the front page (72) Inventor Shintaro Shinmura 1-11-6 Hatagaya, Shibuya-ku, Tokyo Inside Nittan Co., Ltd. (56) References JP-A-2-116997 (JP, A) JP-A-2-116997 (JP, B2) (58) Field surveyed (Int. Cl. ⁶ , DB name) G08B 17/00-17/12 H01H 37/00-37/56

Claims (7)

(57) [Claims] 1. A method for adjusting the sensitivity of a differential spot-type fire detector, comprising: setting a contact interval of the differential spot-type fire detector to a predetermined position which is wider than a normal position; The device is exposed to an atmosphere in which the pressure is reduced according to a predetermined decompression characteristic, the operation time until the fire detector operates in the reduced pressure atmosphere is measured, and the contact point of the fire sensor to the best point based on the operation time is measured. A method for adjusting the sensitivity of a differential spot-type fire sensor, comprising: determining an interval; and adjusting a contact interval of the fire detector to the determined contact interval. 2. The pressure-reducing characteristic is characterized in that pressure is reduced by a rapid change from the start of pressure-reduction to a predetermined pressure-reducing value, and is reduced by a slow change when the pressure-reducing value exceeds the predetermined pressure-reducing value. A method for adjusting the sensitivity of the differential spot type fire detector according to claim 1. 3. The sensitivity of the differential spot type fire detector according to claim 1, wherein the fire detector is determined to be defective when the measured operation time is not within a predetermined time range. Adjustment method. 4. The differential spot type fire according to claim 1, wherein the contact interval of the fire detector is adjusted by screwing a contact adjusting screw of the fire detector until the determined contact interval is reached. How to adjust the sensitivity of the detector. 5. A sensitivity adjusting device for a fire detector for adjusting the sensitivity of a differential spot-type fire detector, comprising: a closed tank for adjustment capable of storing the fire detector and forming an atmosphere having a predetermined decompression characteristic; An exhaust system for exhausting air in the closed tank for adjustment in accordance with an exhaust drive control signal, and rotating a contact adjusting screw of a fire detector placed in the closed tank for adjustment in accordance with a screw rotation drive control signal Contact screw adjustment device, captures an operation signal from a fire detector placed in the adjustment closed tank, measures the operation time until the fire detector operates in the reduced-pressure atmosphere, and determines the operation time. The contact interval of the fire detector up to the best point is determined based on the calculated contact interval, and a screw rotation drive control signal is output so that the contact interval of the fire detector is adjusted to the determined contact interval. Differential expression spot-type fire detector sensitivity adjustment apparatus characterized by comprising anda adjustment control unit that outputs an exhaust drive signal to. 6. The exhaust control system according to claim 1, wherein the adjustment control device reduces the pressure by a rapid change from the start of the pressure reduction to a predetermined pressure reduction value, and reduces the pressure by a slow change when the pressure reduction value exceeds the predetermined pressure reduction value. 6. A sensitivity adjusting device for a differential spot type fire detector according to claim 5, wherein said sensitivity adjusting device is configured to form a signal. 7. The apparatus according to claim 5, wherein the adjustment control device is configured to determine that the fire detector is defective when the measured operation time is not within a predetermined time range. Sensitivity adjustment device for differential spot type fire detector.