JP3041757B2 - 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, according to the present invention, a differential spot type fire detector is housed in a decompression tank, and a contact interval of the differential spot type fire detector is set to be wider than a normal position in advance. In this state, the pressure in the decompression tank was reduced with a predetermined decompression characteristic, and the sensitivity of the contact interval of the differential spot type fire detector was adjusted. A contact signal was obtained from the differential spot type fire detector. Sensitivity adjustment method of differential spot-type fire detector for terminating sensitivity adjustment of differential spot-type fire detector according to contact interval or time zone at time, and sensitivity realizing sensitivity adjustment method of this fire detector The present invention relates to an adjusting device.

[0003]

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 a contact signal (contact ON). FIG.
2 is a sectional view showing an example of a differential spot type fire detector. FIG. 13 is a plan view of the fire detector, and FIG. 14 is a sectional view of a main part of the fire detector.

[0004] In these figures, a differential spot-type fire detector 101 comprises, for example, a chamber 102 having a U-shaped cross section, a diaphragm mounting frame 103 provided on an upper portion of the U-shaped cross section of the chamber 102, A leak resistance 106 that connects a diaphragm 104 fixed to a diaphragm mounting frame 103, an air chamber 105 surrounded by the chamber 102, the diaphragm mounting frame 103 and the diaphragm 104, and the outside world with a predetermined air resistance value.
A base 107 for mounting the chamber and the like; a movable contact 108 connected to the diaphragm 104; a fixed contact 109 fixed to the base 107 side; and a fixed contact 109 screwed to the base 107. A contact adjusting screw 110 for adjusting the distance D between the movable contact 108 and the fixed contact 109 by moving the contact 109; terminals 111 and 112 electrically connected to the contacts 108 and 109 via electrodes 113 and 114, respectively; It is composed of

In the differential spot-type fire detector 101 having such a structure, when the temperature of the external environment rises, 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 leak resistance of 1
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, and the diaphragm 104 is displaced to move the movable contact 108.
Contacts the fixed contact 109 and outputs a contact signal (contact ON).

[0006] Such a differential spot type fire detector 1
01 is conventionally adjusted when the leak resistance is 10
6, 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.
Is adjusted by the contact adjusting screw 110.

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 are performed. In this stage airflow test, the sensitivity is judged to be normal if the fire detector 101 is exposed to an airflow having a predetermined temperature and a predetermined wind speed and is operated within a predetermined time range from the time of the exposure.

On the other hand, there has been proposed a method for 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, there is an advantage that the connection of the air injection pipe is not required.

[0009]

However, in the sensitivity adjusting method of the conventional differential spot type fire detector, as described above, the sensitivity is adjusted in a state where the leak resistance is not taken into consideration. There is a disadvantage that the sensitivity adjustment is not complete because the sensitivity adjustment is not performed in a state that includes.

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

Further, in the conventional 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, and thus a large amount of fire detection is required. In order to adjust the sensitivity of the vessel, there is a disadvantage that the efficiency is low.

In addition, in the method of measuring the displacement of the diaphragm of the fire detector by arranging the differential spot type fire detector in the depressurized and sealed tank, the displacement of the diaphragm is simply detected by the displacement meter. Therefore, an expensive displacement meter that cannot perform sensitivity adjustment and can reliably measure displacement is required, and there is a disadvantage that 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 detector capable of solving the above-mentioned disadvantages and efficiently adjusting the sensitivity of a large number of fire detectors in a short time. The purpose is. SUMMARY OF THE INVENTION It is an object of the present invention to provide a method and apparatus for adjusting the sensitivity of a differential spot-type fire detector capable of solving the above-mentioned disadvantages and reducing the number of tests.

[0014]

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 described in which a differential spot type fire detector is housed in a decompression tank. After setting the contact interval of the differential spot type fire detector to a predetermined position which is wider than a normal position, and depressurizing the inside of the pressure reducing tank to a predetermined pressure value, the air of the differential spot type fire detector is air-tight. Reduce the pressure so that the differential pressure between the chamber and the decompression tank is constant, and rotate the contact adjustment screw of the differential spot type fire detector so that a contact signal is obtained within a predetermined contact interval. In this case, the sensitivity is adjusted.

In the method of adjusting the sensitivity of the differential spot-type fire detector, when the contact signal cannot be obtained within a predetermined contact interval, the differential spot-type fire detector is determined to be defective. It is characterized by.

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 to accommodate the differential spot-type fire detector in a decompression tank. After setting the contact interval of the fire detector to a predetermined position that is preliminarily widened from the normal position, and depressurizing the inside of the decompression tank to a predetermined pressure value, a differential spot-type fire sensor having standard characteristics is placed in the decompression tank. When housed, decompression is continued so that the differential pressure that would be formed between the air chamber of the differential spot-type fire detector having the standard characteristics and the pressure in the decompression tank becomes constant, The sensitivity is adjusted by rotating a contact adjusting screw of the differential spot type fire detector so that a contact signal can be obtained in a predetermined time zone from a point in time.

In the above sensitivity adjusting method, when the contact signal is obtained before a predetermined time zone from a predetermined time point, or when the contact signal is not obtained even after the predetermined time zone, the differential type It is characterized by making the spot type fire detector defective.

In order to achieve the above object, a sensitivity detector for a fire detector according to the present invention is capable of accommodating or taking out a differential spot type fire detector, and the differential spot type fire detector accommodated therein. A pressure reducing tank that can expose the fire detector to a reduced pressure atmosphere, an exhaust system that exhausts air from the pressure reducing tank, and a contact adjustment screw for the differential spot type fire detector housed in the pressure reducing tank are rotated. A contact screw adjusting device to be driven, and an exhaust system is driven and controlled according to a predetermined exhaust characteristic, and the contact screw adjusting device is driven and controlled, and when there is a contact signal from the differential spot type fire detector. An adjustment control device for terminating the sensitivity adjustment of the differential spot type fire detector when the contact position when the contact signal is obtained is at a predetermined contact interval. Also It is.

Further, the adjustment control device reduces the pressure by a sudden change from the start of the pressure reduction to a predetermined pressure reduction value, and then the differential pressure between the air chamber of the differential spot type fire detector and the pressure reduction tank is kept constant. The driving of the exhaust system is controlled by the exhaust characteristic of continuously reducing the pressure so that

In order to achieve the above object, a sensitivity detector for a fire detector according to the present invention is capable of accommodating or taking out a differential spot type fire detector, and accommodates the differential spot type fire detector accommodated therein. A pressure reducing tank that can expose the fire detector to a reduced pressure atmosphere, an exhaust system that exhausts air from the pressure reducing tank, and a contact adjustment screw for the differential spot type fire detector housed in the pressure reducing tank are rotated. A contact screw adjusting device to be driven, and an exhaust system is driven and controlled according to a predetermined exhaust characteristic, and the contact screw adjusting device is driven and controlled, and when there is a contact signal from the differential spot type fire detector. And an adjustment control device for terminating the sensitivity adjustment of the differential spot-type fire detector when it is within a predetermined time zone.

Further, the adjustment control device reduces the pressure by a sudden change from the start of the pressure reduction to a predetermined pressure reduction value, and then, when a differential spot type fire detector having a standard characteristic is accommodated in the pressure reduction tank. The exhaust system has a reduced pressure characteristic of continuing the reduced pressure so that a differential pressure that will be formed between the air chamber of the differential spot type fire detector and the pressure in the reduced pressure tank of the standard characteristic is constant. Is drive-controlled.

[0022]

According to the sensitivity adjusting method of the differential spot type fire detector according to the present invention, the fire detector is housed in the decompression tank, and the contact adjusting screw of the fire detector is lifted by a predetermined amount, and the predetermined amount is set. Reduce the pressure by the decompression characteristics and reduce the pressure so that the differential pressure between the air chamber of the fire detector and the decompression tank, which has the standard characteristics, is constant, and turn the contact adjustment screw in the direction to reduce the contact interval. When the position is within a predetermined range, the sensitivity adjustment is terminated. Therefore, it is possible to obtain a fire detector whose sensitivity is accurately adjusted, and does not require any special calculation.

In another sensitivity adjustment method of the present invention, since there is a specific time relationship between the position of the setting adjustment screw and the operation signal of the contact, this time interval falls within a predetermined range. Sometimes normal and good. In this case, it is possible to obtain a fire sensor whose sensitivity can be accurately adjusted by applying even a fire sensor having a variation.

In addition, according to the method of adjusting the contact interval between the upper and lower fire sensors, only the direction in which the contact adjustment screw of the fire sensor is screwed in until the determined contact interval is reached,
Errors such as screw adjustment can be absorbed.

In the sensitivity adjusting device for a differential spot type fire detector according to the present invention, the differential pressure between the air chamber of the fire detector and the decompression tank can be made constant, because it is configured as described above.
When the fire detector operation signal is input with the setting screw of the fire detector continued to be screwed in at a constant speed with the contact screw adjustment device, the position of the setting screw is normal when it is within the specified range. It is determined that the fire detector is a good one.

In the sensitivity adjusting device for a differential spot-type fire detector according to the present invention, the differential pressure between the air chamber of the fire detector and the decompression tank can be kept constant, because it is configured as described above.
With the contact screw adjuster, when the fire detector's setting adjustment screw is screwed in at a constant speed and the fire detector's operation signal is input, the time until the operation signal is input is within the specified range. At one time it is a normal fire detector.

[0027]

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 of the differential spot type fire detector shown in FIG. 1 is roughly divided into a pressure reducing tank (closed tank for adjustment) 12, an exhaust system 13, a contact screw adjusting device 14, an exhaust An adjustment control device 15 for driving and controlling the system 13 and the contact screw adjustment device 14 is provided.

The closed tank for adjustment 12 has a closed rectangular parallelepiped shape, and a fire detector mounting table 16 is provided on 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 sensor 18 is provided inside the closed tank 12 for adjustment.
Is provided.

The tank cover 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 and 22 are connected to the terminals 111 and 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 closed tank for adjustment 12 is communicated with an exhaust cylinder 25 via a pipe 24 provided with a three-way solenoid valve 23 in the middle. The three-way solenoid valve 23 communicates the inside of the adjustment closed tank 12 with the outside air, or connects the adjustment closed tank 12 and the exhaust cylinder 25. 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 rod 27. The syringe piston driving device 28 is arranged such that a rod screw 31 is rotatably disposed on a fixed base 30 having a concave shape as viewed from one side, and the rod screw 31 is rotated forward and reverse by, for example, a stepping motor 32, whereby the movable portion 29 is rotated. 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 34 a, 34 b, which are provided with a reflector or the like (not shown) fixed to the movable unit 29 and in which a light emitting diode and a photo sensor are integrally provided.
34c, 34d and 34e may be arranged at regular intervals.

The pressure sensor 18, the lead terminal 21,
22 and the piston position detection unit 33
So that a pressure detection signal from the pressure sensor 18, a contact signal of the fire detector 101, and a piston position detection signal of the piston position detection unit 33 are input to the adjustment control device 15. is there. The adjustment control device 15 is provided with a timer (not shown) so that the operation time can be measured. further,
The adjustment control device 15 includes a solenoid valve 23, a motor 32 of a syringe piston driving device 28, and a contact screw adjustment device 14.
The motor of the syringe piston driving device 28 and the motor of the contact screw adjusting device 14 can be controlled to rotate forward and reverse by the adjustment control device 15. It is.

FIG. 2 is a block diagram showing the sensitivity adjusting device, and is a diagram showing the configuration of the adjustment control device in 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 core for executing various arithmetic processing, a ROM for storing a predetermined program, a RAM for storing predetermined data and necessary constants, 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 is also connected to the interface 51. Thus, the contact 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 pressure sensor 18 is also connected to the interface 51, and a pressure detection signal detected by the pressure sensor 18 is input to the central processing unit 50 via the interface 51. The electromagnetic valve 23, the motor 32 of the syringe piston driving device 28, and the contact screw adjusting device 14 are connected to the interface 52. With this wiring, the three-way solenoid valve 23 is turned on or off under the control of the central processing unit 50. In addition, the motor 3 of the syringe piston driving device 28
Numeral 2 is driven to rotate under the control of the central processing unit 50. With the same wiring, the motor of the contact screw adjusting device 14 is driven to rotate forward or reverse under the control of the central processing unit 50.

Before explaining the operation of the sensitivity adjusting device 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 a fire detector 1 during a stair test.
11 is a characteristic diagram showing a relationship between a pressure difference (internal pressure) Y (vertical axis) between the pressure inside the air chamber 105 and the atmospheric pressure of No. 01 (vertical axis) and a stair test operation time T (horizontal axis). Air chamber 105 of fire detector 101
Pressure Y [mmH ₂ O] in is the staircase test operation time T (seconds), since a relationship that is proportional within a certain time range, when the predetermined time B _t has elapsed from a certain time A _t the internal pressure A _p To B _p linearly. Therefore, Y
Is

[0036]

[Number 1] Y = αT + β, however, alpha = _{[(B p -A p) / (} B t -A t) ] beta = _{[(A p × B t) -} (A t × B p) ] / (B _t -A _t)

As described above, it is given by a function proportional to the time T. As can be seen from FIG. 3, Y =
When it is 0, β = 0.

FIG. 4 shows the air chamber 105 of the fire detector 101.
Pressure Y (vertical axis) and the displacement amount U of the diaphragm 104
FIG. 6 is a characteristic diagram showing a relationship with (horizontal axis). For example, the internal pressure Y [mmH ₂ O] of the air chamber 105 of the fire detector 101 whose characteristic of the diaphragm has the standard characteristic Up is the diaphragm 1
04 is proportional to the displacement [mm] of the
_{When p} is pressurized, the displacement of the diaphragm 104 is C
_d, and the displacement of the diaphragm 104 when a certain pressure D _p becomes D _d. Therefore, the relationship between the detected pressure Y and the displacement amount U is represented by the following Expression 2.

[0039]

[Number 2] Y = γU + δ However, gamma = _{[(D p -C p) / (} D d -C d) ] [delta] = _{[(C p × D d) -} (C d × D p) ] / (D _d -C _d)

Assuming that the internal pressure Y of the air chamber 105 of the fire detector 101 is a common term based on Equations 1 and 2, a proportional relationship is established between the displacement U of the diaphragm 104 and the stair test operation time T. You can see that.

FIG. 5 shows the pressure P in the adjustment closed tank 12.
a, the internal pressure Pb of the air chamber 105 of the fire detector 101 having the standard characteristics in which the air chamber 105 has no defect such as air leak and has a predetermined size of the leak resistor 106, and the two pressures Pa and Pb. Is a characteristic diagram showing the differential pressure ΔY on the vertical axis and the operation time T of the fire detector 101 during pressure reduction on the horizontal axis.

FIG. 5 shows the pressure Pa in the closed tank 12 for adjustment.
, The pressure Pb of the air chamber 105 of the fire detector 101 also drops sharply as the pressure drops. From time Td, it is assumed that the fire detector 101 having the standard characteristics is housed in the closed tank 12 for adjustment, and the pressure Pb of the air chamber 105 of the fire detector 101 having the standard characteristics and the closed tank 12 for adjustment. The pressure Pa in the closed tank for adjustment 12 is gradually reduced so that the difference (ΔY) from the pressure Pa in the inside is always constant. In FIG. 4, reference numeral Uq indicates the case of the diaphragm 104 having the characteristic in which the displacement amount U is small, reference numeral Up indicates the case of the diaphragm 104 in which the displacement amount U is the standard characteristic, and reference numeral Ur indicates the case of the diaphragm 104 having the characteristic in which the displacement amount is large. .

As described above, by keeping the pressure difference ΔY constant at all times, the contact adjusting screw 110 for moving the fixed contact 109 of the fire detector 101 is rotated at a constant rotation speed in the direction in which the contact interval is reduced. The sensitivity can be adjusted. This will be described with reference to FIG.

FIG. 6 shows the movable contact 10 of the fire detector 101.
8, the moving amount U of the contact 8 and the moving amount of the contact adjusting screw 110 (moving amount of the fixed contact 109) are plotted on the vertical axis, the time T is plotted on the horizontal axis, and the movable contact 108 using the diaphragm 104 having different displacements is used. The movement amounts Uq, Up, and Ur are indicated by solid lines, and the movement amounts of the fixed contacts 109 are indicated by dotted lines. In the drawing, reference numeral Uq indicates the case of the diaphragm 104 having a small displacement amount U, reference sign Up indicates the case of the diaphragm 104 having the displacement amount U of the standard characteristic, and reference sign Ur indicates the case of the diaphragm 104 having the large displacement amount. . As can be seen from this figure, when the fixed contact 109 of the fire detector 101 is narrowed at a constant speed from a predetermined interval F (the initial pulling position by rotating the contact adjustment screw 110 in the reverse direction) F, the illustrated figure is obtained. As shown by a symbol G (dotted line), the interval narrows in proportion to the time T. Therefore, the amount of movement of the contact adjustment screw 110 is between the upper limit Gu (time Ta) and the lower limit G.
If the contacts 108 and 109 are in contact (contact ON) during d (time Tc), the fire detector 101 can be handled as normal. As described above, the differential pressure ΔY of the fire detector 101 in the case of the standard characteristic is set to be constant, and the contact adjusting screw 110 of the fire detector 101 is rotated at a constant rotation speed in a direction in which the interval between the contacts 108 and 109 is reduced. If a contact ON signal is obtained within a predetermined range (see the upper limit Gu (time Ta) to the lower limit Gd (time Tc)), it means that the sensitivity of the fire detector 101 has been adjusted.

The first embodiment will be described based on such a concept. FIG. 7 is a flowchart for explaining a first embodiment of the sensitivity adjustment method of the differential spot type fire detector executed by the apparatus of FIGS. 1 and 2. In the first embodiment, there is no defect of air leakage in the air chamber 105 except for the characteristics of the diaphragm 104 of the fire detector 101, and the resistance value of the leak resistor 106 is reliable. This is to explain an adjustment method in a case of a very small size.

First, the tank lid 19 is opened, and the fire detector 101 is placed at a predetermined position on 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 adjustment screw 110.

When such a state is reached, the central processing unit 50 of the adjustment control unit 15 supplies a drive signal to the contact screw adjustment unit 14 via the interface 52.
Thereby, the contact screw adjusting device 14 is rotated according to the drive signal, and the contact adjusting screw 110 of the fire detector 101 in the adjustment closed tank 12 is moved to a predetermined position (for example, reference F in FIG. 6).
(See step 201). At the same time, the central processing unit 50 gives a drive signal to the three-way solenoid valve 23, closes the three-way solenoid valve 23, and shuts off the passage to the atmosphere (step 201).

Next, the central processing unit 50 gives a drive control signal for rotating at high speed via the interface 53 to the motor 32 of the syringe piston drive unit 28 (step 202). 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 detection unit 33,
The rotation of the motor 32 is controlled based on the detection signal from the piston position detection unit 33. Thereby, the movable part 29
Moves to the right side in the figure at a high speed, and accordingly, the syringe piston 26 is withdrawn at a high speed. By executing this from time 0 to time Td shown in FIGS. 5 and 6, the pressure is rapidly reduced for a predetermined time (step 202). Therefore, the fire detector 101 placed in the closed tank for adjustment 12 is placed under the rapid pressure reduction characteristics as shown in FIG.

Then, after the time Td shown in FIG. 5, the central processing unit 50 of the adjustment control device 15
A drive signal for rotating the motor 32 of the syringe piston driving device 28 at a low speed is output so that the pressure difference ΔY between the pressure Pa in the pressure sensor 2 and the pressure Pb in the air chamber 105 of the fire detector 101 becomes constant (step 203). ). As a result, the syringe piston 26 is pulled out so as to have a very gentle decompression characteristic per unit time (step 203). Therefore, the adjustment closed tank 12
The fire detector 101 disposed inside is exposed to a reduced pressure state with a very gentle slope per unit time as shown by the characteristic Pa in FIG. Further, the pressure in the air chamber 105 of the fire detector 101 at this time is Pb, and the differential pressure ΔY is constant. And the central processing unit 50
A rotation drive signal is given to the contact screw adjusting device 14 in a direction in which the interval between the contacts 108 and 109 of the fire detector 101 is narrowed (step 203). Thereby, fire detector 1
01 of the contact adjusting screw 110 at a constant rotational speed.
8, 109 rotate in the direction in which the distance between them decreases, and the fixed contact 10
9 is moved downward in the figure.

Then, the central processing unit 50 of the adjustment control unit 15 starts to determine whether or not the contact ON signal is input from the fire detector 101 in such a state within a predetermined time (step 204; NO). , Step 205; NO).
That is, the central processing unit 50 includes the adjustment closed tank 12.
When the contact ON signal is not input from the fire detector 101 placed in the box and placed under the pressure-reducing characteristic (step 204; NO), the position of the fixed contact 109 falls below the lower limit Gd in FIG. (Step 20)
5) When the position of the fixed contact 109 is not less than the lower limit Gd (step 205; NO), there is a possibility that the contact ON signal may still be input, so the contact ON signal is again output from the fire detector 101. It is determined whether or not there is (step 204).

Here, when a contact ON signal is input to the central processing unit 50 from the fire detector 101 mounted in the closed tank for adjustment 12 (step 204; YES),
The central processing unit 50 stops the drive signal given to the contact screw adjusting device 14 and gives a signal to open the three-way solenoid valve 23 (step 206). Thereby, the inside of the adjustment closed tank 12 becomes equal to the atmospheric pressure.

Then, the central processing unit 50 determines that the position of the contact adjustment screw 110 (fixed contact 109) of the fire detector 101 is the upper limit Gu based on the drive signal given to the contact screw adjustment device 14.
It is determined whether it is before or after (step 207).

Here, when the position of the contact adjusting screw 110 (fixed contact 109) of the fire detector 101 is not before the upper limit Gu (step 207; central processing unit 50).
NO), the position of the contact adjustment screw 110 is set to the upper limit G shown in FIG.
Since it is in the range of u to the lower limit Gd, it is assumed that the sensitivity adjustment has been completed (step 208), and the processing is terminated. The central processing unit 50 determines that the position of the contact adjustment screw 110 (fixed contact 109) of the fire detector 101 is the upper limit G shown in FIG.
If it is earlier than u (step 207; YES), the fire detector 101 is determined to be defective (step 209), and the process ends.

On the other hand, the central processing unit 50 does not receive a contact ON signal from the fire detector 101 placed in the closed tank for adjustment 12 and placed under the reduced pressure characteristic (step 204; NO), and it is determined from the drive signal given to the contact screw adjusting device 14 whether or not the contact adjusting screw 110 has passed the lower limit Gd position shown in FIG. 6 (step 205). Step 205; YES), since the fire detector 101 is defective, the drive signal given to the contact screw adjusting device 14 is stopped and a signal for opening the three-way solenoid valve 23 is given (step 210). Thereby, the inside of the adjustment closed tank 12 becomes equal to the atmospheric pressure. And the fire detector 101
Is determined to be defective (step 209), and the process ends.

As described above, in the first embodiment, the fire detector 101 is housed in the closed tank 12 for adjustment, and the contact adjustment screw 110 of the fire detector 101 is rotated to fix the fixed contact 10.
The distance between the movable contact 9 and the movable contact 108 is set to a predetermined position F which is previously widened (pulled up) by a predetermined range from the normal contact distance, and in this state, the inside of the adjustment closed tank 12 is depressurized with predetermined depressurization characteristics. The position of the contact adjustment screw 110 (fixed contact 109) when the contact signal is issued from the fire detector 101 under the atmosphere is determined, or when the contact on signal is not issued, the contact adjustment screw 110 (fixed contact) is determined. 109) is determined, and a predetermined contact adjusting screw 11 is determined.
Only the one at the position of 0 (fixed contact 109) is regarded as normal. The fire detector 101 can be obtained with a simple test, one test, and accurate operation.

In the above embodiment, the fire detector 101
Since the contact adjusting screw 110 can be adjusted by the contact screw adjusting device 14 and the exhaust system 13 can be adjusted to a predetermined pressure reducing property in the adjusting closed tank 12, a large number of fire detectors 101 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 adjustment screw 110 of the fire detector 101 is screwed (turned only in one direction) until the obtained contact interval is reached. Backlash (play) with the adjustment 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 a predetermined time Td, and after the predetermined time Td, the pressure is reduced slowly (so that the differential pressure ΔY becomes constant). As a result, 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
When the position of the fixed contact 109 is not within the predetermined range,
Since it can be determined that the fire detector 101 is defective,
Testing and adjustment of the fire detector 101 can be performed in a short time. Further, in this embodiment, when there is reliability in a component that does not need to consider air leakage or the like, a test can be performed only by adjusting the contact point without requiring complicated calculation processing.

The second embodiment will be described based on the above concept. FIG. 8 is a flowchart for explaining a second embodiment of the sensitivity adjustment method of the differential spot type fire detector executed by the apparatus of FIGS. The description of the second embodiment shown in FIG. 8 takes into account the air leak of the air chamber 105 of the fire detector 101 and the variation of the leak resistance when the characteristic of the diaphragm 104 is standard. The characteristics shown in FIG. 9 and FIG. 10 below indicate those having a standard and a variation, but show characteristics having a pass range.

FIG. 9 shows a case where the characteristics of the fire detector to which the second embodiment is applied vary, and the pressure Pa in the closed tank 12 for adjustment, the air chamber 105 of the fire detector 101 are shown. The vertical axis represents the internal pressures Px, Pp, Pz and the differential pressures ΔYx, ΔYp, ΔYz of the two pressures Pa, Pb,
It is a characteristic diagram which shows the operation time T of the fire detector 101 at the time of pressure reduction on a horizontal axis.

FIG. 10 is a graph showing the movement amount U of the movable contact 108 of the fire detector 101 and the movement amount of the contact adjusting screw 110 (movement amount of the fixed contact 109) on the vertical axis, and the time T on the horizontal axis. The moving amounts Ux, Up, Uz of the contact 108 are shown by solid lines, and the moving amounts of the fixed contact 109 are shown by dotted lines.

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
22 is the same as that of the first embodiment up to the point where the screw drive unit 20 comes into contact with the contact adjustment 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.
As a result, the contact screw adjusting device 14 rotates in response 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, refer to a symbol F in FIG. 10) (step). 301). at the same time,
The central processing unit 50 gives a drive signal to the three-way solenoid valve 23, closes the three-way solenoid valve 23, and shuts off the passage to the atmosphere (step 301).

Next, the central processing unit 50 supplies a drive control signal for rotating at high speed via the interface 53 to the motor 32 of the syringe piston drive unit 28 (step 302). 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 detection unit 33,
The rotation of the motor 32 is controlled based on the detection signal from the piston position detection unit 33. Thereby, the movable part 29
Moves to the right side in the figure at a high speed, and accordingly, the syringe piston 26 is withdrawn at a high speed. By executing this from time 0 to time Td, the pressure is rapidly reduced for a predetermined time (step 302). Therefore, the fire detector 101 placed in the closed tank for adjustment 12 is placed under the rapid pressure-reducing characteristics.

Next, after the time Td shown in FIGS. 9 and 10, the central processing unit 50 of the adjustment control device 15 temporarily stores the fire detector 101 having the standard characteristic Up in the adjustment closed tank 12.
The pressure difference ΔYp between the pressure Pa in the closed tank for adjustment 12 and the pressure Pp in the air chamber 105 of the fire detector 101 will be constant. A drive signal for rotating the motor 32 of the drive device 28 at a low speed is output (step 303). As a result, the syringe piston 26 is pulled out so as to have a very gentle pressure reduction characteristic per unit time (step 303). Therefore, the fire detectors 101 (some of which have standard characteristics and some of which have variations) arranged in the closed tank for adjustment 12 are:
As shown by the characteristic Pa in FIG. 9, the device is exposed to a decompression state with a very gentle slope per unit time. At this time, if the fire detector 101 has the standard characteristic Up, the pressure in the air chamber 105 becomes Pp as shown in FIG.
These differential pressures ΔYp are constant. In the case of a fire detector 101 having a variation, for example, a fire detector 101 having no air leakage and a high leak resistance value, the air chamber 10
The pressure of 5 becomes Px, and conversely, for example, there is an air leak,
And / or fire detector 101 when leak resistance is low
In this case, the pressure in the air chamber 105 becomes Pz. In this case, as shown in FIG. 9, the differential pressure of each fire detector 101 is such that the differential pressure ΔYp is constant for the standard characteristic and the differential pressure ΔYx is gradually increased for the one having a high leak resistance value. Conversely, for those having a low leak resistance value, the differential pressure ΔYz gradually decreases. This tendency also holds between the characteristics Up, Ux, and Uz in FIG. 10 showing the relationship between the amount of movement of the movable contact 108 and the time T.

Next, the central processing unit 50 sends the contacts 108, 1 of the fire detector 101 to the contact screw adjusting device 14.
A rotation drive signal is given in a direction in which the interval of 09 is reduced (step 303). As a result, the contact adjusting screw 110 of the fire detector 101 rotates at a constant rotational speed in a direction in which the interval between the contacts 108 and 109 decreases, and moves the fixed contact 109 downward at a constant speed. At the same time (time Td), the timer 53 is activated (step 304). Then, the contact adjusting screw 110 of the fire detector 101 moves downward in the figure in proportion to the time T, as shown by the dotted line in FIG. 10, so that the interval between the contacts 108 and 109 becomes smaller every moment.

The central processing unit 50 of the adjustment control device 15
It is determined whether a contact ON signal is input from the fire detector 101 in such a state within a predetermined time (step 305; NO, step 306; NO). That is, when the central processing unit 50 is placed in the closed tank for adjustment 12 and does not receive a contact-on signal from the fire detector 101 placed under the reduced pressure characteristic (step 305; NO), The value of the timer 53 is checked to determine whether the elapsed time has exceeded the predetermined time Tc (step 3).
06), when the elapsed time does not exceed the predetermined time Tc (step 306; NO), it is highly likely that the fire detector 101 is normal as can be seen from FIG. It is determined whether there is an ON signal (step 305).

Here, when a contact ON signal is input to the central processing unit 50 from the fire detector 101 mounted in the closed tank for adjustment 12 (step 305; YES),
The central processing unit 50 stops the drive signal given to the contact screw adjusting device 14 and gives a signal to open the three-way solenoid valve 23 (step 307). Thereby, the inside of the adjustment closed tank 12 becomes equal to the atmospheric pressure.

The central processing unit 50 controls the timer 5
The counting time of 3 is taken in, and it is determined whether the time is before the predetermined time Ta (step 308, see FIG. 10). Here, the central processing unit 50 takes in the count time of the timer 53 and when the time is not before the predetermined time Ta shown in FIG. 10 (after the time Ta in FIG. 10, step 3).
08; NO), the fire detector 101 sets the time Ta in FIG.
Fire detector 1 because it is always within the range of ~ Tc
01 (step 30).
9), end the processing.

The central processing unit 50 includes a timer 53
When the count time is taken before the predetermined time Ta shown in FIG. 10 (step 308; YES), the fire detector 101 is determined to be defective (step 310), and the process is terminated.

On the other hand, the central processing unit 50 is placed in the closed tank for adjustment 12 and receives no contact-on signal from the fire detector 101 placed under the reduced pressure characteristic (step 306; NO), the counting time of the timer 53 is checked, and the time is determined by a predetermined time Tc shown in FIG.
It is determined whether or not the time has passed (step 306). If the time of the timer 53 has exceeded the predetermined time Tc (step 306; YES), as shown in FIG. Therefore, the drive signal given to the contact screw adjusting device 14 is stopped and a signal for opening the three-way solenoid valve 23 is given (step 311).
Thereby, the inside of the adjustment closed tank 12 becomes equal to the atmospheric pressure. Then, the fire detector 101 is determined to be defective (step 310), 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 adjustment screw 110 of the fire detector 101 is rotated to fix the fixed contact 10.
The distance between the movable contact 9 and the movable contact 108 is set to a predetermined position F which is previously widened (pulled up) by a predetermined range from the normal contact distance, and in this state, the inside of the adjustment closed tank 12 is depressurized with predetermined depressurization characteristics. The elapsed time when the operation (contact ON) signal is issued from the fire detector 101 under the atmosphere is measured, and when the operation (contact ON) signal is not issued, the elapsed time is measured. Range (time T
Since the sensitivity is determined to be normal when a is within a to Tb), the operation of the fire detector 101 includes the action of the leak resistor 106, and the fire detector 1 that operates correctly
01 will be obtained.

In the above embodiment, the fire detector 101
Since the contact adjusting screw 110 can be adjusted by the contact screw adjusting device 14 and the exhaust system 13 can be adjusted to a predetermined pressure reducing property in the adjusting closed tank 12, a large number of fire detectors 101 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 adjustment screw 110 of the fire detector 101 is screwed (turned only in one direction) until the obtained contact interval is reached. Backlash (play) with the adjustment screw 110 can be absorbed, and accurate adjustment can be performed.

Further, in this embodiment, the predetermined pressure reduction characteristic is rapidly reduced from the start of the adjustment until a predetermined time Td, and after the predetermined time Td, the pressure is reduced with a slow change (differential pressure ΔY is constant). 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.

FIG. 11 shows the movable contact 1 of the fire detector 101.
10 is a characteristic diagram in which the vertical axis represents the movement amount U of the reference numeral 08 and the movement amount of the contact adjustment screw 110 (the movement amount of the fixed contact 109), and the horizontal axis represents time T. In FIG. 11, the pressure differences XU1 to XU3 and YU1 to YU in the air chamber 105 of the plurality of fire detectors 101 and in the closed tank 12 for adjustment having different characteristics.
3, ZU1 to ZU3 are shown by solid lines, and the amount of movement of the fixed contact 109 is shown by dotted lines.

In FIG. 11, first, the symbol XU indicates the characteristic of the fire detector 101 having a high leak resistance, XU1 indicates the characteristic of the large change amount of the diaphragm 104, and XU2
Is the characteristic of the standard one with the change amount of the diaphragm 104,
XU3 indicates the characteristics of the diaphragm 104, although the amount of change is small.

Similarly, the symbol YU indicates the characteristic of the fire detector 101 having a standard leak resistance, and the symbol YU1 indicates the diaphragm 1
04 shows the characteristic of the large change amount, YU2 shows the characteristic of the standard change amount of the diaphragm 104, and YU3 shows the characteristic of the small change amount of the diaphragm 104, respectively.

Similarly, the symbol ZU indicates the characteristic of the fire detector 101 when the leak resistance is small or there is an air leak, ZU1 indicates the characteristic of the large change amount of the diaphragm 104, and ZU2 indicates the change amount of the diaphragm 104. Indicates the characteristic of the standard type, and ZU3 indicates the characteristic of the small change amount of the diaphragm 104.

In FIG. 11, time Ta to time T
Items up to c are treated as good products. In such a characteristic, by applying the flowchart of FIG. 8 described above, the fire detector 101 between the time Ta and the time Tc is determined to be a non-defective product, and the fire detector 101 having the characteristic that has passed the time Tc before the time Ta. It can be defective. As described above, even when a plurality of characteristics are present, the predetermined time Ta to T
The fire detector 101 in the area c can be handled as a good product.

[0081]

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 detector in this state to an atmosphere in which pressure is reduced according to a predetermined pressure reduction characteristic, and adjusting the sensitivity when the contact interval when the fire detector operates in the reduced pressure atmosphere is within a predetermined range. The operation of the fire detector includes the action of the leak resistance,
A fire detector that operates correctly will be obtained. Further, since the contact interval of the fire sensor is adjusted in one direction until the contact interval of the fire sensor reaches a predetermined contact interval, an adjustment error can be absorbed. Further, it is sufficient to simply perform the contact adjustment, and the test and the adjustment can be performed without the need for complicated arithmetic processing.

According to the second aspect of the present invention, when a contact signal is not obtained within a range of a predetermined contact interval, the differential spot type fire detector is determined to be defective, so that the quality judgment is speeded up. it can.

According to the sensitivity adjusting method of the differential spot type fire detector according to the third 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. Exposing the fire detector in this state to an atmosphere in which pressure is reduced according to a predetermined pressure reduction characteristic, measuring an operation time until the fire detector operates in the reduced pressure atmosphere, and setting the operation time within a predetermined range. Is judged as non-defective, the operation of the fire detector includes the action of leak resistance, and a fire detector that operates accurately can be obtained. In addition, since the contact interval of the fire detector is adjusted in one direction until the contact interval of the fire detector is adjusted within the predetermined time range, an error such as screw adjustment can be absorbed. Furthermore, according to this adjustment method, it is easy to set a time range for determining good or bad, so that it is possible to easily adjust the sensitivity of the fire detector having characteristics that vary.

According to a fourth aspect of the present invention, when a contact signal is obtained before a predetermined time period from a predetermined time point, or when a contact signal is not obtained after a predetermined time period, the difference is determined. Since the dynamic spot type fire detector is determined to be defective, it is possible to speed up the determination of a good product and obtain a fire detector that operates accurately.

According to the sensitivity adjusting device of the differential spot type fire detector according to the fifth aspect of the present invention, the contact adjusting screw of the fire detector is lifted by a predetermined amount, and then the differential pressure is adjusted to be constant. Since the pressure is reduced and the contact adjustment screw of the fire detector is adjusted by the contact screw adjuster, the product is considered to be good when the contact interval when the operation signal of the fire detector is obtained is within a predetermined range. In addition, it is possible to provide an adjusting device that can efficiently obtain a fire detector whose sensitivity is accurately adjusted in a short time. In addition, it is possible to obtain an adjustment device that can execute a test and an adjustment without performing a complicated calculation process.

According to a sixth aspect of the present invention, after the pressure is reduced by a sudden change from the start of pressure reduction to a predetermined pressure reduction value, the pressure difference between the air chamber of the differential spot type fire detector and the pressure reduction tank is reduced. Since the drive of the exhaust system is controlled by the exhaust characteristic of continuously reducing the pressure so as to be constant, an arbitrary pressure reducing characteristic can be obtained.

According to the sensitivity adjusting device for a differential spot type fire detector according to the present invention, the contact point of the differential spot type fire detector is set at a predetermined position which is wider than a normal position. Set with the adjusting device, and expose the fire detector in this state to an atmosphere in which the pressure is reduced according to the predetermined pressure reduction characteristics.
The operation time until the fire detector operates in the reduced-pressure atmosphere is measured, and when the operation time is within a predetermined range, it is determined to be a non-defective product. Can be provided in a short time and efficiently.

In the adjustment control device according to the present invention, after the pressure is reduced by a sudden change from the start of the pressure reduction to a predetermined pressure reduction value, a differential spot type fire detector having standard characteristics is accommodated in the pressure reduction tank. Sometimes with the decompression characteristic of continuing the decompression so that the differential pressure that will be formed between the air chamber of the differential spot type fire detector of the standard characteristic and the pressure in the decompression tank becomes constant. Since the drive of the exhaust system is controlled, an arbitrary pressure reduction characteristic can be obtained.

[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 a relationship between the pressure inside the air chamber of the fire detector and the operation time of the stair test at the time of the stair test in the first embodiment.

FIG. 4 is a characteristic diagram showing a relationship between an internal pressure of an air chamber of the fire detector and a displacement amount of a diaphragm in the first embodiment.

FIG. 5 is a 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 in the first embodiment. FIG.

FIG. 6 is a characteristic diagram for explaining an operation of judging pass / fail of the fire detector in the first embodiment.

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

FIG. 8 is a flowchart for explaining a sensitivity adjustment method of the differential spot type fire detector executed by the apparatus of the second embodiment.

FIG. 9 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. 10 is a characteristic diagram for explaining an operation of judging pass / fail of the fire detector in the second embodiment.

FIG. 11 is a characteristic diagram for explaining an operation of judging pass / fail of the fire detector in the third embodiment.

FIG. 12 is a sectional view showing a differential spot-type fire detector.

FIG. 13 is a plan view showing the fire detector.

FIG. 14 is a cross-sectional view showing a main part of the fire detector.

[Explanation of symbols]

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

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G08B 17/00 G08B 17/04

Claims (8)

(57) [Claims] 1. A method for adjusting the sensitivity of a differential spot-type fire detector, comprising: storing a differential spot-type fire detector in a decompression tank; After setting the pressure in the decompression tank to a predetermined pressure value, the pressure difference between the air chamber of the differential spot-type fire detector and the decompression tank is constant. So that a contact signal can be obtained within a predetermined contact interval.
A sensitivity adjustment method for the differential spot-type fire detector, wherein the sensitivity is adjusted by rotating a contact adjustment screw of the differential spot-type fire detector. 2. The differential spot type fire detector according to claim 1, wherein when a contact signal is not obtained within a predetermined contact interval range, the differential spot type fire detector is determined to be defective. How to adjust the sensitivity of the detector. 3. A method for adjusting the sensitivity of a differential spot-type fire detector, comprising the steps of: accommodating a differential spot-type fire detector in a decompression tank; After setting the pressure in the decompression tank to a predetermined pressure value, and setting the differential spot type fire detector of the standard characteristics in the decompression tank, the standard characteristics are set. The pressure reduction is continued so that the differential pressure that will be formed between the air chamber of the differential spot-type fire detector and the pressure in the pressure reducing tank becomes constant, and from a predetermined time to a predetermined time period A sensitivity adjustment method for a differential spot-type fire detector, wherein the sensitivity is adjusted by rotating a contact adjustment screw of the differential spot-type fire detector so that a contact signal is obtained. 4. When a contact signal is obtained before a predetermined time period from a predetermined time point, or when a contact signal is not obtained after a predetermined time period, the differential spot type fire detector is activated. 2. The method for adjusting the sensitivity of a differential spot-type fire detector according to claim 1, wherein said method is defective. 5. A sensitivity adjusting device for a fire detector for adjusting the sensitivity of a differential spot-type fire detector, wherein said differential spot-type fire detector can be housed or taken out, and said housed difference can be adjusted. A decompression tank that can expose the dynamic spot-type fire detector to a decompressed atmosphere, an exhaust system that exhausts air in the decompression tank, and a contact point of a differential spot-type fire detector housed in the decompression tank A contact screw adjusting device for rotating the adjusting screw; a drive control of an exhaust system according to a predetermined exhaust characteristic; and a drive control of the contact screw adjusting device, wherein a contact signal from the differential spot type fire detector is output. And an adjustment control device for terminating the sensitivity adjustment of the differential spot type fire detector when the contact position when the contact signal is obtained is at a predetermined contact interval. Differential expression spot-type fire detector sensitivity adjustment device according to claim. 6. The adjustment control device reduces the pressure between the air chamber of the differential spot-type fire detector and the pressure reduction tank after the pressure is reduced by a sudden change from the start of the pressure reduction to a predetermined pressure reduction value. 6. The sensitivity adjustment device for a differential spot-type fire detector according to claim 5, wherein the exhaust system is driven and controlled by an exhaust characteristic of continuously reducing the pressure so as to satisfy the following condition. 7. A sensitivity adjustment device for a fire detector for adjusting the sensitivity of a differential spot-type fire detector, wherein the differential spot-type fire detector can be housed or taken out, and the difference of the housed difference can be adjusted. A decompression tank that can expose the dynamic spot-type fire detector to a decompressed atmosphere, an exhaust system that exhausts air in the decompression tank, and a contact point of a differential spot-type fire detector housed in the decompression tank A contact screw adjusting device for rotating the adjusting screw; a drive control of an exhaust system according to a predetermined exhaust characteristic; and a drive control of the contact screw adjusting device, wherein a contact signal from the differential spot type fire detector is output. And an adjustment control device for terminating the sensitivity adjustment of the differential spot type fire detector when it is within a predetermined time zone. Sensitivity adjustment device. 8. The pressure control device according to claim 1, further comprising: a pressure change unit configured to reduce the pressure by a sudden change from the start of the pressure reduction to a predetermined pressure reduction value. The exhaust system has a reduced pressure characteristic of continuing the reduced pressure so that a differential pressure that will be formed between the air chamber of the differential spot type fire detector and the pressure in the reduced pressure tank of the standard characteristic is constant. 8. A sensitivity adjusting device for a differential spot type fire detector according to claim 7, wherein the sensitivity adjusting device controls the driving of the fire sensor.