JP2006095487A - Strainer-contamination clogging detection system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a strainer-contamination clogging detection system for detecting an arrival of a strainer at a state of clogging set in advance for obtaining the timing of replacing the strainer for preventive purpose before a machine such as an air conditioner is abnormally stopped due to shortage of water supply. <P>SOLUTION: The strainer-contamination clogging detection system is interposed on the way of a conduit guiding water to be fed to the machine and detects clogging of the strainer accompanying contamination of the strainer filtering dust in the water. This detection system has a tubular screen the central axis of which is declined to the water flow direction in the conduit, a strainer body containing the screen while supporting it elastically, and a sensor arranged between the screen and the strainer body for measuring the pressure which the screen receives from water or the displacement of the screen. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a strainer dirt clogging detection system that detects clogging caused by dirt on a strainer that removes dust in water interposed in a pipeline through which water is circulated.

  Usually, in a cooling / heating device, cold / hot water is circulated by a pump in a pipe line including a heat source device and a heat exchanger. And in order to remove the foreign material mixed in cold / hot water, the strainer which incorporated the screen in the pipe line is interposed (for example, refer patent document 1).

JP 2004-62999 A

  However, since the screen is left in the circulating cold / hot water for a long time, the scale is deposited on the screen and clogging progresses. Since the degree of contamination of the strainer is estimated from the operation data of the cooling / heating device, the strainer is left until an abnormal stop or modulation of the air conditioner is detected. Thus, there is a problem that the amount of circulating water supplied to the cooling device is reduced, heat exchange is insufficient, and the cooling device stops abnormally.

  An object of the present invention is to provide a strainer that detects that a predetermined degree of clogging has been reached in order to determine when to replace the strainer proactively before a device such as a cooling / heating device abnormally stops due to insufficient supply of cold / hot water. It is to provide a dirt clogging detection system.

  The strainer dirt clogging detection system according to the present invention is a strainer dirt clogging detection system that detects clogging caused by dirt on a strainer that filters foreign matter in the water interposed in the middle of a pipe that guides water to be supplied. In this case, the water flows in the flow direction from the cylindrical screen disposed with the bottom surface inclined with respect to the flow direction of the water flowing in the pipeline, and one opening connected to the pipeline. The water flows out from the other opening in the flow direction, and is interposed between the strainer body that elastically supports the screen and encloses the screen, and the screen and the strainer body. And a sensor for measuring the pressure received or the displacement of the screen.

  The effect of the strainer dirt clogging detection system according to the present invention is to detect the degree of dirt clogging by measuring the pressure applied to the screen or the displacement of the screen due to the clogging of the screen. The need to replace or clean the screen can be understood and dealt with appropriately before an abnormal stop due to a lack of supply.

Embodiment 1 FIG.
FIG. 1 is a block diagram of a strainer dirt clogging detection system according to Embodiment 1 of the present invention. 2 is a cross-sectional view taken along the line AA of FIG. In FIG. 1, the strainer portion is shown as a cross-sectional view.
In the following description, an air conditioning facility provided with a package will be described as an example, but the present invention can be applied to a water circuit provided with a water circuit for supplying cold / hot water such as a chiller.

Although not shown, the air conditioner equipped with this strainer contamination clogging detection system is cooled by a package for controlling the temperature of the discharged air, a cooling tower for once cooling the cold / hot water returned from the package with outside air, and the cooling tower. A pump for supplying the cool / warm water to the package, and a pipe line through which the cool / warm water is circulated and returned from the cooling tower to the cooling tower via the package.
The package is provided with a heat exchanger, and heat is exchanged between the cold / hot water and the refrigerant on the primary side of the package and between the refrigerant and air on the secondary side. Thus, when heat exchange is performed, if the flow rate of cold / hot water decreases, the heat exchange rate of the refrigerant deteriorates. And if the flow rate of this cold / hot water becomes below a predetermined amount, since the compression more than the performance of a compressor will be performed, a compressor will fail.

Since the foreign substances are mixed in the chilled / hot water circulated in this way, the Y-strainer 1 is interposed in the pipe line between the cooling tower and the package in order to remove it so as not to flow downstream.
As shown in FIG. 1, the Y-type strainer 1 includes a strainer body 2 and a screen 3. The strainer body 2 has a pipe line connected to an opening provided at one end, an inflow part 4 through which cold / hot water flows, and a direction of a streamline of cold / hot water flowing through the pipe line (from the left in FIG. 1). The screen holding portion 5 holds the screen 3 so that the bottom surface is inclined 45 degrees with respect to the horizontal direction (to the right in the right direction) and the outflow portion 6 from which the cold / warm water flows out from the Y-strainer 1. The angle between the direction of the streamline and the bottom surface is not limited to 45 degrees, and the present invention can be applied as long as cold / hot water flows from the bottom surface and flows out from the side surface.
The cool / warm water flows from the inflow portion 4 through the bottom surface of the screen 3 close to the inflow portion 4 and flows into the screen 3, and then passes through the side surface of the screen 3 and flows out to the outflow portion 6. And the foreign material contained in the water which flows in from the inflow part 4 is collected on the side surface of the screen 3. In addition, the streamline of the center of cold / hot water is represented by the dotted line in FIG.

  The strainer dirt clogging detection system 7a provided in such an air conditioning system is elastic to the strainer main body 2 with respect to the screen 3 in which the rings 12a and 12b are fitted at both ends in the central axis direction and the ring 12a near the inflow portion 4. Pressure sensor 9 for measuring the pressure applied to the side surface of the screen 3, and the pressure measurement value measured by the pressure sensor 9 is determined in advance. It is comprised from the warning device 10a which issues a warning when it becomes more than a threshold value.

The screen 3 is a cylindrical mesh with both bottoms open. The ring 12 b on the bottom surface opposite to the bottom surface near the inflow portion 4 of the screen 3 is pressed against the water lid 14 via the packing 13. The ring 12b is supported so as to be rotatable about an axis 15 perpendicular to the direction of the streamline of the ring 12b. Therefore, the bottom surface of the screen 3 close to the inflow portion 4 swivels around its axis 15 as a rotation center.
On the other hand, the ring 12 a close to the inflow portion 4 is supported by the elastic support portion 8. As shown in FIG. 2, the elastic support portion 8 includes a plurality of leaf springs 17 having one end fixed to the inner surface of the strainer body 2 and the other end fixed to the outer surface of the ring 12a.

When cold / hot water flows through the Y-shaped strainer 1, a force is applied in the normal direction of the side surface of the screen 3. The screen 3 is held in a state where this force and the pressure of the leaf spring 17 are balanced.
Next, the change with time of the force applied to the screen 3 will be described. The force applied to the screen 3 is composed of the force applied to the cross section of the screen 3 and the resistance of the cold / hot water flowing through the opening of the screen 3. And since a scale deposits and accumulates on the crosspiece part of the screen 3, and a crosspiece part becomes wide, bigger force is added. Furthermore, since the opening becomes narrow, the resistance component increases. In the scale, alkali particles of calcium and magnesium compounds contained in water are precipitated and deposited as highly stable crystals.

In this way, the force pushing in the normal direction of the side surface of the screen 3 increases with time, and the pressure measurement value of the pressure sensor 9 also increases. And since this pressure measurement value is sent to the alarm device 10a, a threshold value is determined in advance, and by comparing this threshold value with the pressure measurement value, the package is abnormal due to insufficient supply of cold / hot water. Can be detected before stopping.
And since insufficient supply of cold / hot water can be detected proactively, it is possible to prevent the compressor from operating beyond its capacity and causing a failure.

In the first embodiment, since the pressure sensor 9 is installed in the direction in which the screen 3 is pushed, the measured pressure increases as the scale is deposited and deposited. On the contrary, the direction in which the screen 3 is pushed. The pressure sensor 9 may be installed in the opposite direction so that the measured pressure becomes smaller as the scale is deposited.
The strainer can also be measured by measuring the change in pressure by rotatably supporting the ring 12a near the inflow portion 4 and interposing the pressure sensor 9 between the ring 12b near the water lid 14 and the strainer body 2. It is possible to detect clogging of dirt.

  Further, in the first embodiment, the screen 3 has been described as a bottomless cylinder. However, even if a bottom is provided on the bottom surface of the screen 3 on the water lid 14 side and a change in force applied to the bottom is detected, the screen 3 is stained. The degree of clogging can be detected.

  Further, in the above-described first embodiment, the screen replacement time is obtained by comparing the pressure measurement value with a predetermined threshold value, but by changing this threshold value according to the usage status of the device, The usage status can be reflected at the time of screen replacement.

Embodiment 2. FIG.
FIG. 3 is a block diagram of a strainer dirt clogging detection system according to Embodiment 2 of the present invention. In FIG. 3, the strainer portion is shown as a cross-sectional view.
The strainer dirt clogging detection system according to the second embodiment is different in that the displacement of the screen 3 is detected instead of the pressure detection of the strainer dirt clogging detection system 7a according to the first embodiment. The same reference numerals are attached to the parts, and the description is omitted.

  As shown in FIG. 3, the strainer clogging detection system 7b is close to the inflow portion 4 so that the screen 3 with the rings 12a and 12b fitted at both ends in the central axis direction and the screen 3 can move in the central axis direction. A guide support portion 20 that guides and supports the ring 12a with respect to the strainer body 2, a coil spring 21 interposed between the ring 12b and the water lid 14 for pulling the screen 3 in the direction of the water lid 14, and a water lid 14 are vertically arranged A displacement sensor 22 whose tip is in contact with a part of the ring 12b, and an alarm device 10b that issues an alarm when a displacement measurement value measured by the displacement sensor 22 exceeds a predetermined threshold value.

  In the displacement sensor 22, a coaxial inner cylinder is guided by the inner surface of the outer cylinder, and when an axial force is applied to the tip of the inner cylinder, the inner cylinder sinks into the outer cylinder. When the inner cylinder sinks to a certain depth, the inner cylinder and the outer cylinder are electrically connected. In this way, it can be turned on / off electrically depending on how the inner cylinder sinks.

  It is set so that the displacement sensor 22 is turned on at the start of use of the Y-type strainer. After that, when cold / hot water is circulated and the scale starts to deposit on the screen 3, the force that pushes the side of the screen 3 toward the outflow portion 6 increases. It moves in the direction away from the water lid 14 in the direction. Then, when the screen 3 moves by a predetermined length, the displacement sensor 22 is turned off, an off signal is sent to the alarm device 10b, and a dirt clogging alarm is issued.

  As described above, since the alarm is issued when the screen is displaced beyond a predetermined value, the screen can be replaced at an appropriate time before the device malfunctions.

  In the second embodiment described above, the screen 3 is pulled toward the water lid 14 by the coil spring 21, but the screen 3 is provided with a coil spring interposed between the ring 12 a close to the inflow portion 4 and the strainer body 2. Even if it is pulled toward the water lid 14 in the direction of the central axis, the displacement of the screen 3 can be measured.

Embodiment 3 FIG.
The strainer dirt clogging detection system according to the third embodiment is obtained by adding a blockage state calculating means for calculating the blockage state of the pipeline to the alarm device according to the first embodiment.
As described in the first embodiment, when the scale is deposited on the screen 3, the force that pushes the side surface of the screen 3 increases, and when the pressure detection value detected by the pressure sensor 9 exceeds a predetermined threshold value, The water flowing in the road is once drained and the screen 3 is replaced. Thus, the pressure detection value after replacing the screen 3 returns to the original value, but is slightly lower than the pressure detection value when the screen 3 is replaced one time before. And when it replaces the screen 3 several times over many years, it will fall gradually. The reason for the decrease is considered to be that the scale that precipitates and accumulates in the pipe gradually closes the pipe, so that the flow rate becomes small and the force pushing the side surface of the screen 3 becomes small.
Therefore, the blockage state calculation means stores the pressure detection value immediately after the replacement of the screen 3, and the rate of decrease becomes equal to or greater than a predetermined value based on the pressure detection value when the pipe is newly provided. When it is necessary to change the pipeline or remove the scale, an alarm is issued.

  Such a strainer dirt clogging detection system judges that the blockage of the pipeline is progressing and issues an alarm when the pressure after the screen replacement is greatly reduced compared to the pressure when the pipeline is newly installed. In addition, it is possible to prevent the equipment from being abnormally stopped as the supply cold / hot water is reduced due to the blockage of the pipeline.

1 is a block diagram of a strainer dirt clogging detection system according to Embodiment 1 of the present invention. FIG. It is sectional drawing of the AA cross section of FIG. It is a block diagram of the strainer dirt clogging detection system concerning Embodiment 2 of this invention.

Explanation of symbols

  1 Y-strainer, 2 strainer body, 3 screen, 4 inflow part, 5 screen holding part, 6 outflow part, 7a, 7b strainer dirt clogging detection system, 8 elastic support part, 9 pressure sensor, 10a, 10b alarm device, 12a , 12b ring, 13 packing, 14 water lid, 15 shafts, 17 leaf spring, 20 guide support, 21 coil spring, 22 displacement sensor.

Claims (5)

In the strainer dirt clogging detection system that detects clogging caused by dirt on the strainer that filters foreign matter in the water interposed in the middle of the pipe that guides the water to be supplied,
A cylindrical screen disposed with the bottom surface inclined with respect to the direction of flow of water flowing through the pipe;
The water flows in from the one opening connected to the pipe in the flowing direction, the water flows out from the other opening in the flowing direction, and the strainer main body enclosing while elastically supporting the screen;
A sensor that is interposed between the screen and the strainer body and measures the pressure received by the screen from the water or the displacement of the screen;
A strainer dirt clogging detection system characterized by comprising: The screen has one end of the cylinder close to the one opening elastically supported by the strainer body, and the other end of the cylinder is rotatably supported by the strainer body,
The strainer dirt clogging detection system according to claim 1, wherein the sensor is a pressure sensor interposed between the one end and the strainer body. The screen is supported such that one end of the cylinder close to the one opening is movable in the central axis direction of the cylinder by the strainer body, and the other end of the cylinder is attached to the strainer body via a spring. On the other hand, it is elastically supported in the direction of the central axis,
The strainer clogging detection system according to claim 1, wherein the sensor is a displacement sensor that measures a displacement of the other end in the central axis direction.   The strainer clogging detection system according to any one of claims 1 to 3, further comprising an alarm device that issues an alarm when the measured pressure or displacement is greater than or less than a predetermined threshold value.   Record the initial pressure received by the screen provided in the new pipe and the pressure immediately after the replacement received by the screen every time the screen is replaced, and the pressure immediately after the replacement is a predetermined ratio or more than the initial pressure. 2. The strainer dirt clogging detection system according to claim 1, further comprising an alarm device that issues an alarm that the pipe line is blocked when the line is reduced.

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