JP2005140028A - Compressed air supply system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compressed air supply system capable of quickly carrying out procedures for removing the causes of the mixture of drain into compressed air. <P>SOLUTION: The compressed air supply system comprises an air compressor 1 and a dryer 2 for removing moisture from compressed air created by the air compressor, wherein the compressed air from which moisture is removed by the dryer is supplied to compressed air consuming equipment 5. In an area on the downstream side of the dryer and on the upstream side of the compressed air consuming equipment, a drain detector 3 is provided for detecting drain mixed in the compressed air. When the drain detector detects the drain mixed in the compressed air, it alarms or stops the operation of the air compressor. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a compressed air supply system, and more particularly, to a compressed air supply system including a dryer that removes moisture in compressed air generated by an air compressor.

  Many devices that consume compressed air dislike moisture in the compressed air. In such a system for supplying compressed air to compressed air consuming equipment, a dryer for removing moisture from the compressed air generated by the air compressor is provided and dried by the dryer to obtain dry compressed air. (For example, Patent Document 1 to Patent Document 3). The dryer has a heat exchanger provided with an air cooler section and a precooler section, and the moisture is removed from the compressed air by cooling the compressed air with this heat exchanger and condensing the moisture. ing. Further, the dryer has a drain discharge portion having a trap structure to prevent the compressed air from flowing out, and drains moisture due to the moisture removed from the compressed air from the drain discharge portion (for example, Patent Document 1). ).

Japanese Patent Laid-Open No. 10-30568 JP 2000-73953 A Japanese Patent Laid-Open No. 2003-176784

  As described above, in a compressed air supply system in which a dryer is provided to generate dry compressed air, a phenomenon that drain is mixed into the dry compressed air may be caused. For example, when the piping of the drain discharge part is clogged due to use over time or the trap structure part breaks down, the drain stays excessively in the air cooler part, and the excessive retention of the drain causes mixing of the drain into the compressed air. Also, when the compressed air supply system pressure is excessively low and the compressed air flows at an abnormally high speed, the high-speed compressed air can also entrain the drain into the dry compressed air. Arise. Furthermore, when the dehumidifying capacity of the dryer is reduced and the humidity of the dry compressed air does not fall below a predetermined level, the moisture in the compressed air is condensed downstream of the dryer to become drain, thereby causing the contamination of the drain. If such contamination of the compressed air is caused, the drain may enter the compressed air consuming device and cause a major failure.

  There is known a technique for dealing with mixing of drain into compressed air by providing a separator for water droplet separation on the outlet side of the precooler or the air cooler (Patent Document 1). Patent Document 2 discloses a technique in which a dryness of compressed air is further increased by providing a hollow fiber air dryer downstream of the dryer. Although this technique is not necessarily intended to deal with the drain contamination problem, it can eventually cope with the drain contamination problem. These conventional techniques are effective to some extent with respect to the problem of contamination of the compressed air in the dryer. However, this only removes the drainage mixed in the compressed air by a separator or a hollow fiber air dryer, and it remains as a therapeutic treatment.

  As described above, the inclusion of drain into the compressed air in the dryer is mainly caused by the occurrence of problems in the dryer or abnormal pressure conditions in the compressed air supply system. Therefore, it is the most effective countermeasure to the drain contamination problem to make it possible to quickly remove the cause.

  The present invention has been made on the basis of such knowledge, and an object of the present invention is to provide a compressed air supply system capable of promptly performing a treatment for eliminating the cause of the contamination of compressed air.

  For the above purpose, the present invention includes an air compressor and a dryer that removes moisture in the compressed air generated by the air compressor, and the compressed air from which moisture has been removed by the dryer is compressed air consumption equipment. In the compressed air supply system configured to supply to the above, a drain detector that detects drain mixed in the compressed air is provided at a site downstream of the dryer and upstream of the compressed air consuming device, When the drain detector detects the drain in the compressed air, an alarm is generated or the operation of the air compressor can be stopped.

  Further, according to the present invention, in the compressed air supply system as described above, a swirl flow is formed in the compressed air that has flowed in, and the swirl unit that separates drain from the compressed air by centrifugal separation using the swirl flow, and the swirl unit separate A drain detector having a structure including a drain reservoir for storing the drain and a drain sensor provided in the drain reservoir is used.

  Further, in the present invention, in the compressed air supply system as described above, a drain trap that can detect a defective state of drain discharge and generate a defective state signal is provided in the drain discharge portion of the dryer. Yes.

  In the present invention, for the compressed air supply system as described above, the drain trap includes a drain pot that stores drain, a drain sensor that detects when the level of the drain stored in the drain pot reaches a detection water level, and The drain valve is opened in response to the detection by the drain sensor, and the drain pot is provided with an electromagnetic valve that discharges the stored drain, and the drain is discharged before a reference time has elapsed since the drain was discharged. The drain sensor generates the defective state signal when the drain is stored up to the detected water level in the pot.

  In the present invention, a drain detector is provided so that the mixed drain can be detected in the compressed air from the dryer, and when the mixed drain is detected, the operation of the air compressor is stopped or an alarm is issued. To be able to. For this reason, it is possible to quickly inform the administrator of the compressed air supply system of the contamination of the dry compressed air. This makes it possible to quickly take measures to remove the cause of the contamination of the dry compressed air.

  FIG. 1 schematically shows a configuration of a compressed air supply system according to an embodiment. The compressed air supply system detects an air compressor 1 that generates compressed air, a dryer 2 that generates dry compressed air by removing moisture from the compressed air, and a drain that is mixed in the dry compressed air downstream of the dryer 2. The drain detectors 3 are connected to each other via a compressed air pipe 4, and the compressed air is supplied to the compressed air consuming device 5. The compressed air supply system is provided with a control device 6 that controls the operation of the air compressor 1, and an alarm device 7 is connected to the control device 6. In addition, the arrow line in a figure has shown the transmission relationship of the various signals mentioned later, and the block arrow has shown the flow of compressed air.

  FIG. 2 shows an example of a specific structure of the dryer 2. The dryer 2 has a heat exchanger 11. The heat exchanger 11 includes an air cooler 14 that cools and dehumidifies the compressed air A by heat exchange with a low-temperature refrigerant that is circulated and supplied from the refrigeration cycle 12 through the refrigerant pipe 13, and an air cooler 14. 14 is provided with a precooler section 15 for pre-cooling the compressed air A at the front stage of the air cooler section 14 by heat exchange with the dry compressed air Ad generated at 14.

  Compressed air A, which is generated by the air compressor 1 and contains a large amount of moisture, flows into the heat exchanger 11 and is first precooled by the precooler 15 and then condensed by cooling in the air cooler 14. To dry compressed air Ad. The dry compressed air Ad is discharged downstream from the dryer outlet 16. During this time, the air cooler 14 generates drainage D due to condensation of moisture. The generated drain D falls to the bottom of the air cooler portion 14 and flows down toward the drain discharge portion 17 and is discharged therefrom. The drain discharge portion 17 is provided with a drain pipe 18 and a drain trap 19. The drain trap 19 provides the drain discharge part 17 with a trap structure for preventing compressed air from flowing out of the drain discharge part 17. The drain trap 19 will be described later.

  In such a dryer 2, the drain pipe 18 may be clogged with aging dirt, resulting in poor drainage of the drain. In addition, the auto drain trap 19 may malfunction due to dirt or the like, thereby causing drain discharge failure. If such a drain discharge failure is caused, the drain D is excessively accumulated in the heat exchanger 2 and in some cases, the drain D may overflow from the dryer outlet 16. Drain will be mixed. In addition, even if drainage is normal, if the compressed air supply system has an excessively low pressure and the compressed air flows at an abnormally high speed, the high-speed compressed air is used as the heat exchanger 2. Entraining the drain inside also causes the drain to be mixed into the dry compressed air. In addition, the dehumidifying capacity of the dryer 2 may decrease with age, but in such a case, the humidity of the dry compressed air does not drop below a predetermined level, and the moisture in the compressed air is reduced downstream of the dryer 2. Condensation may result in drainage, which may be mixed. And if such drainage is mixed into the dry compressed air, the drain may enter the compressed air consuming device 5 and cause a major failure.

  The drain detector 3 is provided in order to cope with such contamination of the dry compressed air. In other words, the drain detector 3 is connected to the compressed air pipe 4 at a site downstream of the dryer 2 and upstream of the compressed air consuming device 5, and is provided in the dry compressed air supplied to the compressed air consuming device 5. Detect contaminated drain. When the detection is performed, a drain detection signal is output to the control device 6. Upon receiving the drain detection signal from the drain detector 3, the control device 6 stops the operation of the air compressor 1 or causes the alarm 7 to generate an alarm. The operation stop of the air compressor 1 and the alarm generation of the alarm device 7 can be appropriately set as required by the user of the compressed air supply system as required. For example, when a device that extremely dislikes moisture is operated as the compressed air consuming device 5, the operation of the air compressor 1 is stopped and an alarm is generated. Otherwise, only an alarm is generated.

  In the present embodiment, such a drain detector 3 is also provided with a drain removing function for separating and removing the drain from the compressed air. FIG. 3 shows a structural example of the drain detector 3 having a drain removing function. The drain detector 3 includes a compressed air inflow path 21, a compressed air outflow path 22, a swivel unit 23, a drain pool 24, and a drain sensor 25, and a signal output cable 26 is connected to the drain sensor 25. ing. The compressed air inflow passage 21 is connected to the compressed air piping 4 of FIG. 1, and the dry compressed air Ad from the drain 2 flows in from here. The compressed air inlet 21 is formed in a pipe structure that allows dry compressed air Ad to flow into the swirl 23 along the inner surface of the swirl 23 formed in a cylindrical shape. Therefore, the dry compressed air Ad that has flowed into the swirl unit 23 forms a swirl flow RF there. Then, the drainage D mixed therein is separated and removed from the dry compressed air by the centrifugal separation action by the swirling flow RF. The dry compressed air Ad that has been separated from the drain D flows down through a compressed air outflow path 22 that is formed in a pipe structure and has one end thereof facing the center of the swivel unit 23.

  The drain D separated and removed from the dry compressed air Ad falls into a drain reservoir 24 provided below the swivel unit 23 and accumulates. When the amount exceeds a certain level, a drain sensor 25 installed in the drain reservoir 24 is used. Detected. The drain sensor 25 in the illustrated example is a float type and has a float 25f. That is, when the float 25f rises according to the amount of drain D stored in the drain reservoir 24 and comes into contact with the sensing unit 25s, drain detection is performed, and the drain detection signal is output to the control device 6 in FIG. Is done. Here, in addition to the float type, for example, a hot wire resistance type can be used as the drain sensor.

  As described above, the drain detector 3 is provided so as to detect drainage mixed in the dry compressed air from the dryer 2, and the operation of the air compressor 1 is stopped when the drain detector 3 detects the drain. By making it possible to generate a warning or to issue an alarm, it is possible to quickly inform the administrator of the compressed air supply system or the like of contamination of the dry compressed air. This makes it possible to quickly take measures to remove the cause of the contamination of the dry compressed air.

  In the present embodiment, as described above, in addition to coping with the drain mixing problem by detecting the drain mixing in the dry compressed air by the drain detector 3, the drain trap 19 in the drain discharging unit 17 of the dryer 2 is also used. A structure for detecting a drain discharge failure state of the drain discharge unit 17 is provided. FIG. 4 shows an example of the structure of such a drain trap 19. The drain trap (auto drain trap) 19 includes a drain pot 31 formed in a cylindrical shape, a drain sensor 32, and an electromagnetic valve 33, and a signal output cable 34 is connected to the drain sensor 32.

  The drain trap 19 is connected in series in the middle of the drain pipe 18, and the drain D flowing down the drain pipe 18 flows into the drain pot 31 and accumulates there. When the storage amount reaches the detected water level, the sensing unit 32s of the drain sensor 32 senses it and opens the electromagnetic valve 33. When the electromagnetic valve 33 is opened, the stored drain D flows down to the drain pot 31 and the stored drain is discharged. If this stored drain discharge is made normally, it will not accumulate to the detected water level unless the reference time t has elapsed. However, if the drain trap 19 or the drain pipe 18 has a discharge failure and the stored drain may remain, the stored drain is accumulated up to the detected water level in a time shorter than the reference time t. Therefore, in such a case, the drain sensor 32 is caused to output a drain discharge failure state signal. This drain discharge failure state signal is output to the control device 6 via the signal output cable 34. The control device 6 that has received the drain discharge failure state signal from the drain detector 3 stops the operation of the air compressor 1 or receives an alarm 7 in the same manner as when the drain detection signal is received from the drain detector 3. Alarms.

  As described above, by making it possible to detect the drain discharge failure state in the drain trap 19, it is possible to quickly detect the drain discharge failure that is a major cause of the contamination of the drain, and it is possible to respond quickly. Further, by combining such a drain discharge failure state detection in the drain trap 19 with detection of drain contamination in the compressed air by the drain detector 3, and further a drain separation / removal function in the drain detector 3, It becomes possible to deal with the mixing problem more effectively.

  As described above, according to the present invention, it is possible to quickly notify the administrator of the compressed air supply system and the like of contamination of the dry compressed air, thereby eliminating the cause of the contamination of the dry compressed air. Treatment can be performed quickly. Therefore, the present invention can be used as useful in the industrial field using compressed air.

It is a figure showing typically the composition of the compressed air supply system by one embodiment. It is a figure which shows the example of the specific structure of a dryer. It is a figure which shows the example of the specific structure of a drain detector. It is a figure which shows the example of the specific structure of a drain trap.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Air compressor 2 Dryer 3 Drain detector 5 Compressed air consumption equipment 19 Drain trap 23 Swing part 24 Drain reservoir 25 Drain sensor 31 Drain pot 32 Drain sensor 33 Solenoid valve A Compressed air D Drain

Claims (4)

A compressor that includes an air compressor and a dryer that removes moisture in the compressed air generated by the air compressor, and that supplies compressed air from which moisture has been removed by the dryer to compressed air consumption equipment In the air supply system,
When a drain detector for detecting the drain mixed in the compressed air is provided at the downstream side of the dryer and the upstream side of the compressed air consuming device, and the drain detector detects the drain in the compressed air. In the compressed air supply system, an alarm can be issued or the operation of the air compressor can be stopped.   The drain detector forms a swirl flow in the compressed air that has flowed in, and a swirl unit that separates drain from the compressed air by centrifugal separation using the swirl flow, a drain pool that stores the drain separated by the swirl unit, and The compressed air supply system of Claim 1 provided with the drain sensor provided in the said drain reservoir.   The compressed air supply system according to claim 1 or 2, wherein a drain trap is provided in the drain discharge portion of the dryer so as to detect a defective state of the drain discharge and generate a defective state signal. The drain trap is a drain pot that stores drain, a drain sensor that detects when the water level of the drain stored in the drain pot reaches a detection water level, and a valve that opens according to the detection by the drain sensor. A drain valve is provided with a solenoid valve that discharges the stored drain, and the drain sensor is configured to store the drain up to the detected water level in the drain pot before a reference time elapses after the stored drain is discharged. The compressed air supply system of claim 3, wherein the compressed air supply system is adapted to generate a fault condition signal.

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