Test apparatus for differential distributed type detectors

Abstract

To provide a test device which can easily perform a test of a differential distribution type sensor.SOLUTION: A test device 1, for performing a test of a differential distribution type sensor 10 which senses a fire by detecting pressure rise in an air pipe 11 laid in a warning area by a diaphragm 14 that communicates with the air pipe 11 via an air pipe connection part (cock stand 13) connected with the air pipe, comprises: air injection means (test pump 4) which injects the air into the air pipe; a pressure sensor 2 which is provided between the air pipe and the air pipe connection part and detects the pressure in the air pipe; and a determination processing unit 3 which determines the test result of the differential distribution type sensor on the basis of the output value of the pressure sensor.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] This invention relates to a test device for a differential distributed sensor.

Background Art

[0002] The differential distributed sensor is a type of heat sensor that detects a rapid pressure increase due to the thermal expansion of air in an air tube laid in a monitoring area by a pressure detection means such as a diaphragm to detect a fire.

[0003] In this type of sensor, during inspection, the following multiple types of tests are being conducted (see, for example, Patent Document 1). Operation test (pump test): A test to check whether the sensor operates normally when a predetermined amount of air is injected. Flow test: A test to measure the pressure state when a predetermined amount of air is injected and check whether the air tube is normal. Diaphragm test: A test to measure the pressure state when a predetermined amount of air is injected and check whether the diaphragm is normal. Leak test: A test to measure the pressure state when a predetermined amount of air is injected and check whether the function of the leak resistance is normal.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Conventionally, as a test device, one composed of a syringe (air injection means) and devices such as a manometer (pressure gauge) has been used (see the above Patent Document 1).

[0006] When performing the above tests using conventional testing equipment, it was necessary to connect a syringe and manometer to the sensor as a preparatory step. Additionally, it was necessary to switch the air passage within the cock stand (the part of the sensor body where the air tube is connected) on the sensor side.

[0007] However, the syringe and manometer connections differed for each test, as did the air passage switching point (operationally, the cock handle switching position varied). Therefore, it was necessary to reconnect the test equipment and switch the air passage for each test. Furthermore, air had to be injected separately for each test.

[0008] Therefore, traditionally, conducting the above tests involved a very large number of steps and was a complicated process.

[0009] In view of the above circumstances, this invention aims to provide a test apparatus that can easily perform tests on differential distributed type sensors. [Means for solving the problem]

[0010] This invention relates to a test apparatus for testing a differential distributed type detector that detects a fire by detecting a pressure rise in an air pipe laid in a protected area using a pressure detection unit that communicates with the air pipe and the air pipe connection part to which it is connected, and the test apparatus is characterized by comprising: an air injection means for injecting air into the air pipe; a pressure sensor provided between the air pipe and the air pipe connection part for detecting the pressure inside the air pipe; and a determination processing unit that determines the test result of the detector based on the output value of the pressure sensor.

[0011] In this invention, the pressure sensor may be provided at a connecting portion that connects the air pipe and the air pipe connection portion, and may be detachably provided together with the connecting portion or detachably provided with respect to the connecting portion. The air pipe connection portion may also be provided with a first connecting hole portion to which one end of the air pipe is connected and which communicates with the pressure detection portion, and a second connecting hole portion to which the other end of the air pipe is connected and which communicates with the test hole portion to which the air injection means is connected, and the pressure sensor may be provided between one end of the air pipe and the first connecting hole portion. The pressure sensor may also be provided at a connecting portion that connects one end of the air pipe and the first connecting hole portion, and which is provided with an opening / closing portion that opens and closes communication between the two, and when the opening / closing portion is closed, it may detect the pressure on the air pipe side. The determination processing unit may also estimate the length of the air pipe based on the output value of the pressure sensor. Furthermore, the determination processing unit can estimate the standard pressure reduction range of the air pipe from the estimated length of the air pipe. [Effects of the Invention]

[0012] In this invention, a pressure sensor installed between the air tube and the air tube connection detects the pressure inside the air tube into which air has been injected by the air injection means, and a determination processing unit determines the test result based on the output value of the pressure sensor. Therefore, the test can be performed once without having to reconnect the test equipment for each test, switch the air passage, or inject air separately, significantly reducing the number of steps.

[0013] Therefore, according to this invention, a test apparatus can be provided that allows for easy testing of differential distributed type sensors. [Brief explanation of the drawing]

[0014] [Figure 1]This shows an example of an embodiment of the test apparatus of this invention. Both (a) and (b) are simplified configuration diagrams showing the differential distributed type sensor under test together with the apparatus configuration. (a) shows the state before the test apparatus is connected and the air passage on the sensor side is in the state during monitoring, while (b) shows the state after the test apparatus is connected and the air passage on the sensor side is in the state during testing (the state during testing in this invention, and the state during operation testing and flow testing in the prior art). [Figure 2] This is an operational flowchart showing the flow of the test process using the same test apparatus as described above. [Figure 3] This shows another example of the same test apparatus, and is a configuration diagram similar to Figure 1(b). Note that the opening / closing part is shown in the closed position. [Figure 4] This shows yet another example of the same test apparatus, and is a configuration diagram similar to Figure 1(b). [Modes for carrying out the invention]

[0015] Hereinafter, specific examples of the test apparatus of this invention will be described with reference to Figures 1 to 4, along with specific examples of differential distributed type sensors that are the subject of the test.

[0016] [Differential distributed sensor] First, in Figure 1, the detector 10 is an air-tube type differential distributed detector, consisting of a long air tube 11 laid in a loop in the monitoring area and a box-shaped detector body (generally also called a detection unit; not shown in the figure). Inside the detector body, there is a cock stand 13 (an example of an air tube connection part) to which the air tube 11 is connected, and a diaphragm 14 that communicates with the air tube 11 via the cock stand 13 and detects the pressure inside the air tube 11. When a fire occurs, the diaphragm 14 closes its contacts due to the rapid pressure increase caused by the thermal expansion of the air inside the air tube 11, outputting a fire signal and detecting the fire.

[0017] The cock stand 13 is provided with a first connection hole portion 13a to which one end portion 11a side of the air pipe 11 is connected, a second connection hole portion 13b to which the other end portion 11b side of the air pipe 11 is connected, a test hole portion 13c to which air injection means is connected during a test, and a leak hole portion 13d for discharging the air in the air pipe 11 to the outside.

[0018] Also, inside the cock stand 13, as an air passage, a fixed passage 13e and a switching passage 13f whose passage can be switched are provided. Further, as a mechanism for switching the passage of the switching passage 13f, a flow path switching mechanism portion 13g is provided.

[0019] The fixed passage 13e is provided as a passage that is always fixed and communicates the first connection hole portion 13a and the diaphragm 14. The switching passage 13f has a first state (the state during monitoring, the state in FIG. 1(a)) that communicates among the fixed passage 13e, the second connection hole portion 13b, and the leak hole portion 13d, and a second state (the state during the test in this invention and the states during the operation test and the flow test in the prior art, the state in FIG. 1(b)) that separately communicates between the fixed passage 13e and the leak hole portion 13d and between the second connection hole portion 13b and the test hole portion 13c, and a third state (the states during the diaphragm test and the leak test in the prior art, illustration omitted) that communicates between the second connection hole portion 13b and the leak hole portion 13d, and is provided as a passage that can be switched. The flow path switching mechanism portion 13g is provided to switch the passage of the switching passage 13f by operating an operating means such as a cock handle (not shown).

[0020] The sensor 10 is of a type that has been generally used conventionally, and many of the existing differential distributed sensors are of this type. The test device 1 can perform tests on such a conventional type of differential distributed sensor. However, it can also be used to perform tests on differential distributed sensors of types different from the conventional type, such as those that detect the pressure increase due to the thermal expansion of the air in the air pipe by other detection means.

[0021] [Test Device] ·Basic Configuration As shown in Figure 1, the test apparatus 1 is provided between the air pipe 11 and the cock stand 13 (an example of an air pipe connection part) and consists of a pressure sensor 2 that detects the pressure inside the air pipe 11, a test pump 4 (an example of an air injection means) that injects air into the air pipe 11 through the test hole 13c of the cock stand 13 during the test, and a determination processing unit 3 which is provided as an integral part with the pressure sensor 2 and determines the test result based on the output value of the pressure sensor 2.

[0022] Although the illustrated example shows the case where the pressure sensor 2 and the determination processing unit 3 are integrated, they may also be separate components and installed independently.

[0023] In the test apparatus 1, a pressure sensor 2, located between the air pipe 11 and the cock stand 13, detects the pressure inside the air pipe 11 into which air is injected by the test pump 4, and the determination processing unit 3 determines the test result based on the output value of the pressure sensor 2. As will be explained in detail later, the preparation work involves connecting the pressure sensor 2, the determination processing unit 3, and the test pump 4 (including the connection of the connecting part 5, which will be explained later; however, this can be omitted for permanently installed equipment), and switching the switching passage 13f to the second state (the state during testing in this invention, as well as the state during operation testing and flow testing in the prior art, as shown in Figure 1(b)). The test work involves injecting air into the air pipe 11 using the test pump 4. However, in principle, these operations do not need to be repeated until the end of the test. Therefore, the test can be performed once without reconnecting the test equipment, switching the air passage, or injecting air separately for each test, significantly reducing the number of steps. Consequently, the sensor 10 can be easily tested.

[0024] • Specific examples of each component • Pressure sensor The pressure sensor 2 is a fluid-type sensor that detects and measures the pressure of the air inside the air tube 11 when a predetermined amount of air is injected into the air tube 11 through the test hole 13c, and outputs it as an electrical signal. The output measured value can be a value measured at a constant period (continuously).

[0025] • Placement of pressure sensors As described above, the pressure sensor 2 is installed between the air pipe 11 and the cock stand 13. This allows for retrofitting to the existing sensor 10, making installation easier. More specifically, the position where the pressure sensor 2 is installed is preferably between one end 11a of the air pipe 11 and the first connection hole 13a, as shown in the example in Figure 1. During testing, air is injected into the air pipe 11 from the other end 11b side through the test hole 13c and the second connection hole 13b. In other words, in the example in Figure 1, during testing, the pressure sensor 2 will detect the pressure at a position downstream of the air pipe 11. The air pump 4 is installed between the other end 11b of the air pipe 11 and the second connection hole 13b. While it is possible to detect the pressure at an upstream position of the air pipe 11, detecting the pressure at a downstream position of the air pipe 11 is advantageous because it allows air to be injected by the test pump 4 and the pressure to be detected after the air has flowed throughout the entire air pipe 11. This makes it easier to detect abnormalities, such as when there is a hole in the air pipe 11, as a clear difference in the pressure rise will be observed.

[0026] ·Connection part The pressure sensor 2 can be provided at the connecting portion 5 that connects the air pipe 11 and the cock stand 13. In the example shown in Figure 1, it is provided between one end 11a of the air pipe 11 and the first connection hole 13a of the cock stand 13, and is provided at the connecting portion 5 that connects the two. The connecting portion 5 can be, for example, a joint member having a connection portion to the air pipe 11 side, a connection portion to the cock stand 13 side, and a connection portion to the pressure sensor 2 side.

[0027] The pressure sensor 2 may be provided detachably together with the connecting portion 5, or it may be provided detachably to the connecting portion 5.

[0028] ··Judgment Processing Unit The judgment processing unit 3 records the pressure measurement output from the pressure sensor 2 at predetermined intervals (for example, every second), calculates the pressure rise rate (for example, the percentage increase in the measured value relative to the reference value), compares this pressure rise rate with various thresholds, and makes judgments on the various test results. A microcontroller or the like is used as the judgment processing unit 3.

[0029] ...Estimation function for air pipe length If the amount of air injected into the air pipe 11 is constant, the longer the air pipe 11, the lower the maximum value of the pressure increase. In other words, the maximum value of the pressure inside the air pipe 11 is determined by the length of the air pipe 11. Therefore, the length of the air pipe 11 can be estimated from the maximum pressure value. The determination processing unit 3 has a function to estimate the length of the air pipe 11 in this way. The estimated value of the length of the air pipe 11 can be used to estimate the standard pressure reduction range of the air pipe 11, which will be explained later, but it can also be used to understand the construction status of the air pipe 11 on site.

[0030] • Estimation function for standard pressure drop range of air pipes The standard pressure drop range of the air pipe 11 (the pressure drop range when the air pipe 11 is functioning normally; that is, the difference from the time air is injected (pressurized) by the test pump 4 until the change due to that air disappears) can be estimated from the estimated length of the air pipe 11. The judgment processing unit 3 has a function to estimate such a standard pressure drop range of the air pipe 11. The estimated standard pressure drop range of the air pipe 11 can be used to determine the third threshold for determining the pressure drop range during the "test of the air pipe or leak hole" described later.

[0031] Other functions (control functions, etc.) The test apparatus 1 may have control functions for the operation of a pressure sensor 2, a judgment processing unit 3, a test pump 4, etc., as well as display functions for displaying various test results, etc. For example, the judgment processing unit 3 may have such control functions and display functions.

[0032] Test pump As the test pump 4, an electric device (such as an electric air pump) with the function of injecting a predetermined amount of air is used. Alternatively, a manual syringe or the like may be used instead of an electric device.

[0033] ··power supply For components that require a power source, such as the pressure sensor 2, the judgment processing unit 3, and the test pump 4, batteries can be used as the power source.

[0034] • Permanent installation of testing equipment The components of the test apparatus 1, such as the pressure sensor 2, judgment processing unit 3, connecting unit 5, and test pump 4, can be partially or entirely permanently installed on the sensor 10. For example, if only a portion is permanently installed, the connecting unit 5 can be permanently installed on the sensor 10, and the pressure sensor 2 can be connected to the connecting unit 5 during testing. By doing so, it becomes unnecessary to attach and detach the air pipe 11 during testing.

[0035] Furthermore, if components requiring power, such as the pressure sensor 2, judgment processing unit 3, and test pump 4, are to be permanently installed, their power may be shared with the power supply on the sensor 10 side.

[0036] [Test Method] • Preparation work When testing the sensor 10, the inspector performs the following preparatory tasks: connecting the pressure sensor 2, judgment processing unit 3, connecting unit 5, test pump 4, etc. (this can be omitted for permanently installed units); and switching the switching passage 13f to a second state (which is the state during testing in this invention, as well as the state during operation testing and flow testing in the prior art, as shown in Figure 1(b)) by separately connecting the fixed passage 13e and the leak hole 13d, and the second connection hole 13b and the test hole 13c.

[0037] • Content of various examinations (1) Testing of air pipes (corresponding to conventional flow testing) In the determination processing unit 3, the pressure rise rate is compared with a first threshold for pressure rise determination to determine whether or not there is a pressure rise. If the pressure rise rate does not exceed the first threshold, it is determined that there is no pressure rise. Here, for example, if there is a blockage or a large hole in the air pipe 11, the pressure will not rise. If there is no pressure rise, there is a high possibility that there is an abnormality in the air pipe 11. Therefore, if it is determined that there is no pressure rise, the test result is determined to indicate that there is an abnormality in the air pipe 11.

[0038] (2) Testing of leak holes (corresponding to leak testing in conventional technology) In the judgment processing unit 3, if the test in (1) determines that there is a pressure increase, the value of the pressure increase rate is compared with a second threshold for determining whether there is a pressure decrease, and a judgment process is performed to determine whether there is a pressure decrease or not. If it does not fall below the second threshold, a judgment process is performed to determine that there is no pressure decrease. Here, for example, if there is a blockage in the leak hole 13d, the pressure will not decrease easily. If there is no pressure decrease, there is a high possibility that there is an abnormality in the leak hole 13d. Therefore, if it is determined that there is no pressure decrease, a judgment process is performed to determine that there is an abnormality in the leak hole 13d as a test result.

[0039] (3) Testing of air pipes or leak holes (corresponding to flow tests or leak tests in conventional technology) In the judgment processing unit 3, if a pressure drop is determined in the test in (2), the value of the pressure rise rate is compared with a third threshold for determining the pressure drop, and a judgment process is performed to determine whether the pressure drop exceeds the appropriate range. If it falls below the third threshold, a judgment process is performed to determine that the pressure drop exceeds the appropriate range. Here, for example, if there is a small hole in the air pipe 11 or if the resistance of the leak hole 13d is small, the pressure drop will be large. If the pressure drop exceeds the appropriate range, there is a high possibility that there is an abnormality in the air pipe 11 or the leak hole 13d. Therefore, if it is determined that the pressure drop exceeds the appropriate range, a judgment process is performed to determine that there is an abnormality in the air pipe 11 or the leak hole 13d as a test result.

[0040] Furthermore, the third threshold for determining the pressure drop can be determined by calculating an estimated length of the air pipe 11 from the maximum pressure, calculating an estimated standard pressure drop from the estimated length, and then determining the limit value of the appropriate range from that estimated pressure drop.

[0041] (4) Diaphragm testing (equivalent to operational testing or diaphragm testing in the prior art) In the judgment processing unit 3, if the pressure reduction range is determined to be within the appropriate range in test (3), it is presumed that the air pipe 11 and the leak hole 13d are normal. Therefore, the inspector can check whether the detector 10 activates (fire detection), and if it does not activate, they can determine that there is an abnormality in the diaphragm 4. If it does activate, they can determine that not only the diaphragm 4 but also the air pipe 11 and the leak hole 13d are all normal.

[0042] • Specific examples of operational flows during testing Figure 2 shows an example of the flow of operations from the start of the test to the end of the test, after the preparation work is completed.

[0043] As shown in the figure, after the test starts, in step S1, an operation command is issued to the pressure sensor 2 (including the judgment processing unit 3) and the test pump 4. In step S2, the test pump 4 injects a predetermined amount of air into the air pipe 11, and in step S3, the judgment processing unit 3 records the measured pressure output from the pressure sensor 2 at predetermined intervals. The judgment processing unit 3 calculates the pressure rise rate from the recorded pressure measured values, and then, as a test of the air pipe 11 (the test in (1) above), in step S4, it compares the value of the pressure rise rate with a first threshold for pressure rise determination to determine whether or not there is a pressure rise. If the pressure has not risen and it is determined to be Yes, in step S5, it determines that there is an abnormality in the air pipe 11. On the other hand, if the pressure has risen and it is determined to be No, in order to perform further tests, in step S6, the judgment processing unit 3 estimates the length of the air pipe 11 from the maximum pressure, and in step S7, it estimates the standard pressure drop range from the estimated pipe length. Furthermore, the limit value of the appropriate range is determined from the estimated standard pressure drop range, and a third threshold for determining the pressure drop range is determined. Then, as a test of the leak hole 13d (the test in (2) above), in step S8, the determination processing unit 3 compares the value of the pressure rise rate with the second threshold for determining the pressure drop to determine whether or not there is a pressure drop. If the pressure has not dropped and it is determined to be Yes, in step S9, the determination processing is performed to determine that there is an abnormality in the leak hole 13d. On the other hand, if the pressure has dropped and it is determined to be No, as a test of the air pipe 11 or the leak hole 13d (the test in (3) above), in step S10, the determination processing is performed to compare the value of the pressure rise rate with the third threshold for determining the pressure drop range to determine whether or not the pressure drop range exceeds the appropriate range. If the pressure drop range exceeds the appropriate range and it is determined to be Yes, in step 11, the determination processing is performed to determine that there is an abnormality in the air pipe 11 or the leak hole 13d. On the other hand, if the pressure drop does not exceed the appropriate range and the result is determined to be No, then in step 12, as a final test of the diaphragm 14 (the test in (4) above), the inspector checks whether or not the detector 10 activates (fire detection). If the detector 10 does not activate and the result is determined to be Yes, then in step 13, it is determined that there is an abnormality in the diaphragm 14.On the other hand, if sensor 10 is activated and determined to be "No", then in step 14, it is determined that not only diaphragm 14 but everything is normal, and the test is terminated.

[0044] [Example of configuration changes] While embodiments of this invention have been described above with reference to Figures 1 to 4, the specific configuration is not limited to the embodiments described above, and may include design changes and other modifications that do not depart from the spirit of this invention.

[0045] • Addition of a flow opening / closing mechanism to the connecting section For example, the connecting section 5 can be provided with an opening / closing section 6 that opens and closes the communication between the air pipe 11 side and the cock stand 13 side, as shown in Figure 3. The pressure sensor 2 can be configured to detect the pressure on the air pipe 11 side when the opening / closing section 6 is closed and the flow between the air pipe 11 side and the cock stand 13 side is blocked.

[0046] As a result, if an abnormality is detected during the test of the air pipe 11 or leak hole 13d as described in (3) above, the test can be repeated with the opening / closing part 6 closed (normally the test is performed with the opening / closing part 6 open), and the same test as in (3) above can be performed again to determine whether there is an abnormality in the air pipe 11 or the leak hole 13d.

[0047] • Overhang of connecting section Furthermore, as shown in Figure 4, the connecting portion 5 can be provided so as to straddle the space between one end 11a and the other end 11b of the air pipe 11 and the space between the first connecting hole 13a and the second connecting hole 13b of the cock stand 13, connecting these four parts, and the pressure sensor 2 can be provided on the connecting portion 5 provided in this manner.

[0048] While embodiments of this invention have been described above with reference to Figures 1 to 4, the specific configuration is not limited to the embodiments described above, and may include design changes and other modifications that do not depart from the spirit of this invention. [Explanation of symbols]

[0049] 1: Testing device 2: Pressure sensor 3: Judgment processing unit 4: Test pump 5: Connecting part 6: Opening / closing part 10: Sensor 11: Air pipe 11a: One end 11b: The other end 13: Cock stand 13a: First connection hole 13b: Second connection hole 13c: Test hole 13d: Leak hole 13e: Fixed passage 13f: Switching passage 13g: Flow path switching mechanism 14: Diaphragm

Claims

1. A test apparatus for testing a differential distributed type smoke detector that detects a fire by detecting a pressure increase in an air pipe laid in a protected area using a pressure detection unit that communicates with the air pipe via an air pipe connection, An air injection means for injecting air into the aforementioned air tube, A pressure sensor is provided between the air pipe and the air pipe connection portion to detect the pressure inside the air pipe, A test apparatus characterized by comprising a determination processing unit that determines the test result of the sensor based on the output value of the pressure sensor.

2. The test apparatus according to claim 1, wherein the pressure sensor is provided at a connecting portion that connects the air pipe and the air pipe connection portion, and is detachable together with the connecting portion or detachable from the connecting portion.

3. The air pipe connection section is provided with a first connection hole to which one end of the air pipe is connected and which communicates with the pressure sensing section, and a second connection hole to which the other end of the air pipe is connected and which communicates with the test hole to which the air injection means is connected. The test apparatus according to claim 1, characterized in that the pressure sensor is provided between one end of the air pipe and the first connection hole.

4. The test apparatus according to claim 1, characterized in that the determination processing unit estimates the length of the air pipe based on the output value of the pressure sensor.

5. The test apparatus according to claim 3, wherein the pressure sensor is provided in a connecting portion that connects one end of the air pipe to the first connecting hole, and is provided in a connecting portion that opens and closes communication between the two, and when the opening and closing portion is closed, it detects the pressure on the air pipe side.

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