JP2008133781A - Operation control method for compressor in compressed gas supply system and compressed gas supply system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent gas jetting of a safety valve provided on a holding tank for introducing a compressed gas and emergency stop of a compressor in a machine number control device compressed gas supply system for supervisaly controlling a plurality of compressors. <P>SOLUTION: The supply system for the compressed gas is provided with the holding tank for introducing the compressed gas delivered from the plurality of compressors 101, 102, 103; and the machine number control device 30 for supervisaly controlling an intake control device and a drive control device of the plurality of compressors according to a detection signal of a pressure sensor for detecting a pressure in the holding tank. The other pressure sensor capable of detecting the pressure in the holding tank and an operation control device for individually controlling the respective compressors based on the detection signal of the pressure sensor are provided on the respective compressors respectively, and when the pressure sensor provided in every compressor detects a predetermined maximum set pressure Pmax, control by the machine number control device 30 is released and the respective compressors are individually controlled by the operation control device 40. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention introduces compressed gas supplied from a plurality of compressors whose operation is controlled by a unit control device into a common collective tank to obtain compressed gas, and the compressed gas introduced into the collective tank is The present invention relates to an operation control method for the compressor constituting the compressed gas supply system and a compressed gas supply system in which the operation control method is performed in a compressed gas supply system supplied to a consumer side.

  Compressed gas supplied from a plurality of compressors 10 (101 to 103), for example, compressed air is introduced into a common collective tank 20, and the compressed gas introduced into the collective tank 20 is supplied to the consumer side. The compressed gas supply system 1 is used for supplying compressed gas in, for example, a production factory.

  In such a compressed gas supply system 1, the number control device 30 for comprehensively controlling the compressor 10 (101 to 103) is provided, and the number control device 30 changes the pressure in the collective tank 20. Supplying compressed gas efficiently by controlling the start, stop, and full-load / no-load operation of each compressor 10 (101 to 103) according to a predetermined pattern according to changes in the consumption of compressed gas on the consumption side (See Patent Documents 1 to 4 and FIG. 8).

  Each compressor 10 (101 to 103) constituting such a compressed gas supply system 1 is not only comprehensively controlled by the above-described number control device 30, but is also started and operated independently. The switch provided in the compressed gas supply system 1, in the embodiment shown in FIG. 10, in the embodiment shown in FIG. When the single operation mode is selected, each compressor 10 (101 to 103) is operated independently, and when the linked operation mode is selected, each compressor 10 (101 to 103) is connected to the number control device 30. It is configured to be controlled in a centralized manner.

  As described above, an embodiment of the compressor 10 (101 to 103) configured to be independently operable is as shown in FIG. 9, and the compressor 10 (101 to 103) shown in FIG. When the compressor main body 11 that compresses and discharges the compressed gas and the drive source 12 such as a motor that drives the compressor main body 11 and the compressor main body 11 is an oil-cooled compressor, for example, A receiver tank 15 that introduces both compressed gas and lubricating oil discharged from the compressor body 11 and separates the compressed gas and lubricating oil is provided, and an intake air that controls opening and closing of the intake port of the compressor body 11 A control device 13 and a drive control device 14 for starting and stopping the motor that is the drive source 12 of the compressor main body 11 and controlling the rotational speed as necessary are provided. In the illustrated embodiment, the compressor is provided. Air inlet of main body 11 A suction valve 131 that opens and closes, a conduit 133 that communicates between the operating pressure chamber of the suction valve 131 and the receiver tank 15, and an electromagnetic valve 132 that opens and closes the conduit 133 are provided. The above-described intake control device 13 that controls the opening and closing of the intake port of the compressor body 11 by the input is configured, and is operated by the input of a control signal between the motor 12 and the power source to supply power to the motor 12. An ON / OFF switch and an inverter for changing the voltage waveform output to the motor 12 as necessary are provided, and the drive control device 14 is formed by these.

  An operation control device 40 that outputs control signals to the intake control device 13 and the drive control device 14 is provided for each compressor 10 (101 to 103), and the discharge port of the compressor body 11 and the collective tank In order to prevent the compressed gas from flowing backward from the collecting tank 20 side to the compressor body 11 side in a flow path communicating between 20 (in the illustrated embodiment, a pipe line 18 between the receiver tank 15 and the collecting tank 20). Provided with a check valve 17 for pressure control means 16 for detecting the pressure on the secondary side of the check valve 17 for operation control when each compressor 10 (101 to 103) is operated independently. , The detection signal of the pressure detection means 16 for independent operation control is input to the operation control device 40, and the operation control device 40 controls the intake control device 13 and the drive control device 14 to thereby compress the compressor 10 ( 01-103) and is configured to be capable of performing capacity control in the unit.

In the compressor 10 provided with the operation control device 40 configured as described above, when the single operation mode switch 31 (see FIG. 10) is operated and the single operation mode is selected, the respective compression is performed. The operation control device 40 provided in the machine 10 (101 to 103) uses the control signal (drive control signal, intake control signal) output according to the detection signal input from the pressure detection means 16 for independent operation control of the compressor. The intake control device 13 and the drive control device 14 are controlled in units of compressors,
On the other hand, when the interlocking operation mode is selected, the unit control device 30 causes each compressor 10 (101 to 103) to respond to the detection signal input from the interlocking operation control pressure detection means 21 that detects the pressure in the collective tank 20. ) Is controlled by a control signal (drive control signal, intake control signal) output in response to ().

  As described above, each of the compressors 10 (101 to 103) is operated in conjunction with each other, and the individual operation mode in which each compressor 10 (101 to 103) is independently operated. The configuration of the number control device 30 and the operation control device 40 that can switch the operation mode of the compressor 10 is as shown in FIG. 10 as an example.

  In the embodiment shown in FIG. 10, the unit control device 30 is provided with a single-linked operation changeover switch 31, and the independent-linked operation mode switch 31 can be switched by operating the single-linked operation changeover switch 31. It is configured to be able to. The number control device 30 is provided with a start / stop switch 32 for starting and stopping the entire compressed gas supply system 1.

  Further, the number control device 30 receives the detection signal of the interlocking operation control pressure detection means 21 so that the control signals (drive control signal and intake control signal) for each compressor can be output according to the pressure change in the collective tank 20. A pressure determination unit 33 for inputting and comparing with a predetermined reference pressure and determining a pressure state in the collective tank 20 and a pressure setting unit 34 for storing a reference pressure used as a reference for comparison in the pressure determination unit 33 are provided. When the compressed gas supply system 1 is started by operating the start / stop switch 32, the central control unit 35 of the number control device 30 operates the operation mode setting according to the switching position of the single-linked operation changeover switch 31. A mode signal is output to the operation control device 40 of each compressor 10 (101 to 103), and according to the determination result of the pressure determination unit 33, Intake control signal to be inputted to the intake control unit 13 of the compressor 10 (101 to 103), and outputs a driving control signal to be inputted to the drive control unit 14 to the operation control apparatus 40 of the compressors.

  On the other hand, the operation control device 40 provided in each compressor 10 (101 to 103) has a start / stop switch 411 for starting and stopping the compressor 10 (101 to 103) in units of each compressor 10 when the single operation mode is set. And a first pressure determination unit 412 that compares a secondary side pressure of the check valve 17 with a set pressure based on a detection signal input from the pressure detection means 16 for independent operation control. 412 includes a first pressure setting unit 413 that stores a reference pressure at the time of comparison in 412, and when each compressor 10 (101 to 103) is started by operating the start switch 411, the determination result of the first pressure determination unit 412 Accordingly, a control signal (intake control signal) to be output to the intake control device 13 and a control signal (drive control signal) to be output to the drive control device 14 are output in accordance with the determination result. That includes a central controller 414, the single operation control unit 41 which forms permit independent operation of the compressors These are configured.

  The operation mode set by the operation of the single-linked operation changeover switch 31 of the unit control device 30 by inputting both the control signal output by the individual operation control means 41 and the control signal output by the unit control device 30. Accordingly, the control signal output to the intake control device 13 of the compressor 10 (101 to 103) and the control signal output to the drive control device 14 are input from the central control unit 35 of the number control device 30. An operation mode switching means 42 for selecting and outputting either the control signal or the control signal input from the single operation control means 41 is provided, and the operation mode switching means 42 controls switching of the drive control signal. A drive control signal switching unit 421 and an intake control signal switching unit 422 for controlling switching of the intake control signal are realized.

Prior art document information of the present invention includes the following.
Japanese Examined Patent Publication No. 6-58112 Japanese Examined Patent Publication No. 6-58113 Japanese Utility Model Publication No. 2-40314 JP 58-91386 A

  As described above, in the compressed gas supply system 1 including the plurality of compressors 10 (101 to 103) controlled in an integrated manner, the pressure change in the collective tank 20 that serves as a control reference for the number control device 30 If malfunction or failure occurs in the interlocking operation control pressure detection means 21 that conveys the pressure, the unit control device 30 cannot recognize the pressure change in the collective tank 20, and the pressure in the collective tank 20 rises. However, the number control device 30 does not output a control signal for shifting the compressor 10 to the no-load operation, and as a result, the compressor 10 (101 to 103) performs the full-load operation. continue.

  By continuing the full load operation, the pressure in the collective tank 20 continues to rise and abnormally rises, and the safety valve 22 provided in the collective tank 20 blows, or the pressure of the safety valve 22 provided in the collective tank 20 increases. On the other hand, when the rated pressures of the compressors 10 (101 to 103) are low, the compressors 10 (101 to 103) are overpowered and stop in an emergency.

  As described above, when the safety valve 22 provided in the collective tank 20 is blown or each compressor 10 (101 to 103) is emergency stopped, the supply of compressed gas to the consumption side is stopped, and the pressure in the collective tank 20 is activated. It becomes impossible to operate, for example, an air working machine or the like that uses pressure.

  As a result, in a factory facility or the like in which such an air working machine is incorporated in a production line or the like, the operation is not performed until the cause of the malfunction is removed, such as replacement of the faulty operation control pressure detecting means 21. Is interrupted and productivity is significantly reduced.

  Accordingly, the present invention has been made to solve the above-mentioned drawbacks of the prior art, and the collective tank is caused by malfunction or failure of the interlocking operation control pressure detecting means 21 for detecting the pressure in the collective tank 20. Even when the pressure in the tank 20 rises abnormally, the safety valve 22 provided in the collective tank 20 blows, or the compressor 10 (101 to 103) stops suddenly and the supply of compressed gas to the consumption side stops. An object of the present invention is to provide a compressor control method in the compressed gas supply system 1 capable of controlling the operation of the compressor 10 (101 to 103) and a compressed gas supply system for implementing the method. And

In order to achieve the above object, a compressor control method in the compressed gas supply system 1 of the present invention and a compressed gas supply system 1 that implements this control method are the compressor main body that compresses and discharges the compressed gas that has been sucked in. 11, a drive source 12 such as a motor for driving the compressor main body 11, an intake control device 13 for controlling opening and closing of the intake port of the compressor main body 11, a drive control device 14 for controlling the drive source 12, Independent operation control pressure detection means 16 such as a pressure sensor for detecting the discharge side pressure of the compressor body 11 is provided, and the intake control device 13 is controlled in accordance with a detection signal of the independent operation control pressure detection means 16. A plurality of compressors 10 (101 to 103) each having an independent operation control means 41;
A collection tank 20 common to the plurality of compressors 10 (101 to 103) that introduces the compressed gas discharged from the plurality of compressors 10 (101 to 103) and supplies the introduced compressed gas to the consumption side; ,
A number control device 30 for comprehensively controlling the intake control device 13 and the drive control device 14 of the plurality of compressors 10 (101 to 103) in accordance with a predetermined pattern in accordance with a pressure change in the collective tank 20;
A pressure detection means for interlocking operation control 21 such as a pressure sensor for detecting the pressure in the collective tank 20 and outputting it to the number control device 30;
The single operation mode in which the individual compressors 10 (101, 102, 103) are independently controlled by the single operation control means 41, and the operation of the plurality of compressors 10 (101-103) by the number control device 30. An operation mode changeover switch (single-interlocking operation changeover switch 31) is provided to enable operation mode switching between the interlocking operation modes that are collectively controlled.
When operating with the changeover switch switched to the linked operation mode, the pressure detection means 16 for independent operation control provided in any of the compressors or a predetermined number of compressors exceeds the preset maximum set pressure Pmax. An emergency switching means is provided for switching the operation mode from the interlock operation mode to the single operation mode regardless of the selection of the interlock operation mode by the change-over switch when the pressure is detected. 3).

  In the above configuration, the operation mode switching by the emergency switching means counts the detection time of the pressure equal to or higher than the maximum set pressure Pmax by the independent operation control pressure detection means 16 with a counter or the like, and completes the counting of the predetermined time t4. May be configured to shift to the single operation (claims 2 and 4).

  With the configuration of the present invention described above, in the compressed gas supply system 1 of the present invention, the individual operation control pressure is detected by the individual operation control pressure detection means 16 provided in each compressor 10 (101 to 103). The pressure detected by the detection means 16 is only used for comparison with the no-load operation start pressure PH and the full-load operation return pressure PL, which serve as a reference when controlling the capacity of the compressor 10 (101 to 103). However, since it was also used for comparison with a predetermined maximum set pressure Pmax, it was possible to cause the pressure detection means 16 for independent operation control to determine an abnormal rise in pressure in the collective tank 20.

  As a result, due to malfunction or failure of the interlocking operation control pressure detection means 21 that detects the pressure in the collective tank 20, and further, the malfunction control or failure of the number control device 30 itself, the number control device 30 causes each compressor 10 ( 101-103) When the necessary control signals are not output to the intake control device 13 and the drive control device 14, the pressure in the collective tank 20 rises excessively and reaches the maximum set pressure Pmax. The operation control of the machine 10 (101 to 103) is switched from the linked operation mode to the single operation mode, the control by the number control device 30 is released, and the single operation control means is based on the detection signal of the pressure detection means 16 for single operation control. 41, the pressure in the collective tank 20 does not reach the pressure at which the safety valve 22 injects, and the insufflation of the safety valve 22 can be prevented.

  Further, an emergency stop due to power over of each compressor can be prevented, and supply of compressed gas can be prevented by preventing the supply of compressed gas from being interrupted by the jet of safety valve 22 or the emergency stop of the compressor. .

  Next, embodiments of the present invention will be described below with reference to the accompanying drawings.

[First Embodiment]
The basic configuration of the compressed gas supply system 1 of the present invention and the basic configuration of the compressor 10 (101 to 103) constituting the compressed gas supply system 1 are not limited to this, The operation mode is the same as that of the known compressed gas supply system 1 and the compressor 10 described with reference to FIGS. 8 to 10, and is selected by operating the single-linked operation changeover switch 31 provided in the number control device 30. Accordingly, when the single operation mode is selected, each compressor 10 (101 to 103) is based on the detection signal from the single operation control pressure detection means 16 provided in each compressor 10 (101 to 103). ) Performs the intake control and drive control for each compressor.

  When the linked operation mode is selected by operating the isolated-linked operation changeover switch 31, control is not performed based on the detection signal of the pressure detection means 16 for independent operation control provided in each compressor 10 (101 to 103), and the collective tank Based on the detection signal of the interlocking operation control pressure detection means 21 that detects the pressure in the unit 20, based on the control signal that the unit control device 30 outputs to each compressor 10 (101 to 103) according to a predetermined operation pattern. Thus, the intake air control and the drive control of each compressor 10 (101 to 103) are performed.

  Then, the operation control device 40 of each compressor 10 (101 to 103) is connected to the number control device 30, and the control signal from the number control device 30 is sent to the operation control device 40 of each compressor 10 (101 to 103). Is the same as the apparatus configuration in the conventional compressed gas supply system 1 described with reference to FIG.

  In the compressed gas supply system 1 of the present invention, the above-mentioned interlocking operation control pressure detecting means 21 that detects the pressure in the collective tank 20 during operation in the above-described interlocking operation mode has a malfunction or failure. The number control device 30 does not recognize the pressure increase in the collective tank 20 due to the cause of the trouble, and therefore the collective tank 30 does not output a control signal for shifting the compressor 10 (101 to 103) to the no-load operation. When the internal pressure rises abnormally and exceeds the predetermined maximum set pressure Pmax, the interlock operation mode is canceled and each compressor 10 (101 to 103) is automatically switched to the individual operation mode. By providing the means, the pressure in the collecting tank 20 rises to the pressure of the safety valve 22, and each compressor 10 (101 to 103) is operated with power over. Emergency stop etc. are prevented.

  As described above, the operation of each compressor 10 (101 to 103) can be automatically switched from the linked operation mode to the independent operation mode due to the malfunction or failure of the pressure detecting means 21 for detecting the pressure in the collective tank 20. FIG. 1 shows a configuration example of the number control device 30 of the compressed gas supply system 1 provided with emergency switching means and the operation control device 40 of each compressor 10 (101 to 103).

  In the compressed gas supply system 1 shown in FIG. 1, an embodiment in which the number control device 30 controls three compressors 10 (101 to 103) is shown. In FIG. 1, the operation control device for the first compressor 101 is shown. Only 40 is illustrated and described. Since the configuration of the operation control device 40 in each of the compressors 102 and 103 is the same as that of the operation control device 40 in the first compressor 101, the configuration of the operation control device 40 in the second and third compressors 102 and 103 is omitted. is doing.

  In FIG. 1, the operation control device 40 of each compressor 10 (101 to 103) includes a start / stop switch 411, a first pressure determination unit 412, and a first pressure setting unit 413. Although the operation mode switching means 42 including the signal switching unit 421 and the intake control signal switching unit 422 is provided, the configuration is the same as that of the operation control device 40 described with reference to FIG. 40, when the pressure abnormality in the collective tank 20 is determined based on the detection signal of the pressure detection means 16 for independent operation control provided in each compressor, and the pressure abnormality is determined, 40 differs from the operation control device 40 described with reference to FIG. 10 described above in that it includes pressure abnormality determination means 43 that outputs an abnormality confirmation signal to 40.

  The pressure abnormality determining means compares the pressure detected by the isolated operation control pressure detecting means 16 with a predetermined maximum set pressure Pmax, and determines whether or not the detected pressure is equal to or higher than the maximum set pressure Pmax. Pressure detection means according to the determination result of the pressure determination unit 431, the second pressure setting unit 432 that stores and sets the maximum set pressure Pmax to be compared in the second pressure determination unit 431, and the determination result of the second pressure determination unit 431 When the pressure detected by 16 is equal to or higher than the maximum set pressure Pmax, a pressure abnormality confirmation unit 433 that confirms a pressure abnormality in the collective tank 20 and outputs an abnormality confirmation signal to the number controller 30 is configured. Preferably, an abnormality confirmation signal is output when a pressure equal to or higher than Pmax is detected for a predetermined abnormality confirmation time t4.

  In addition, the number control device 30 shown in FIG. 1 is detected by a pressure setting unit 34 that stores a plurality of set pressures that serve as a reference for control of each compressor 10 (101 to 103), and a pressure detection means 21 for linked operation control. The pressure in the collective tank 20 is compared with the set pressure stored in the pressure setting unit 34 to determine the pressure state in the collective tank 20 and the compressed gas according to the determination result of the pressure determiner 33 The configuration is the same as the configuration of the number control device 30 described with reference to FIG. 10 in that the central control unit 35 that controls the operation of each compressor 10 (101 to 103) constituting the supply system 1 is provided. In addition, a single-linked operation changeover switch 31 for setting whether the operation of the compressor is an independent operation or an interlocked operation, and a compressed gas supply system controlled by the number control device 30 The configuration including the start / stop switch 32 for starting and stopping the whole is the same as that of the unit control device 30 described with reference to FIG. 10 described above, but the central control unit 35 includes: When an abnormality confirmation signal is input from the pressure abnormality determining means 43 provided in the operation control device 40 described above, the operation mode switching means of the operation control device 40 is selected regardless of the selection of the interlock operation mode by the single-interlock operation switch 31. 42, an operation mode switching signal for instructing switching to the single operation mode is output to the abnormality display unit 36 including a liquid crystal display panel, a warning light, a horn, and the like provided on the operation panel of the unit control device 30. The compressed gas supply system described with reference to FIG. 10 described above in that it is configured to indicate that a pressure abnormality has occurred in the collective tank 20. It has become different from the configuration example of.

  Therefore, in the compressed gas supply system 1 of the present embodiment described with reference to FIG. 1, the pressure abnormality determination means 43 provided in the operation control device 40 and the abnormality confirmation output by the pressure abnormality determination means 43. The above-mentioned emergency switching means is inputted by the central control unit 35 of the number control device 30 that inputs a signal and outputs an operation mode switching signal for instructing the operation mode switching means 42 of the operation control device 40 to shift to the single operation mode. It is configured.

  The operation of the compressed gas supply system 1 including the compressors having the operation control device 40 configured as described above and the number control device 30 for controlling the operations of these compressors will be described below.

  2 to 4 are operational flows of the compressed gas supply system 1 including a plurality of compressors 10 (101 to 103). FIG. 2 is a single operation by operating the single-linked operation changeover switch 31 of the number control device 30. The operation flow when the operation mode is selected, and FIGS. 3 and 4 are the operation flows when the interlock operation mode is selected by operating the independent-interlock operation switch 31.

Alone provided on the operation panel of the islanding operation mode count control device 30 - by operating the interlock operation changeover switches 31, when the compressed gas supply system 1 was isolated operation mode (S ₁ -1), the compressor 10 (101 ˜103), only the compressor in which the start switch 411 provided on the operation panel is turned on starts.

When the start switch 411 is turned on (S _1-2 ) and the compressor is started (S _1-3 ), the pressure Pd detected by the pressure detection means 16 for independent operation control provided in the compressor starts the no-load operation. is compared with the pressure PH (S ₁ -4), it sensed pressure Pd is full-load operation of the compressor until the no-load operation start pressure PH (0.70 MPa, for example), the sensed pressure Pd idling When the starting pressure PH is exceeded, the compressor is shifted to no-load operation (S ₁ -5).

This shift to no-load operation, the timer unshown starts counting (S ₁ -6), along with whether or not a predetermined time has elapsed t0 is determined (S ₁ -7), sensing pressure Pd is determined (S ₁ -8), the detected pressure Pd before elapse of a predetermined time t0 (60 seconds for example) is counted falls below full load operation restoration pressure PL (0.60 MPa, for example), the compressor return to full-load operation (S ₁ -9), the count again is reset by the counter pressure determined (S ₁ -4) following tasks sensed pressure Pd is carried out.

On the other hand, when the duration of the no-load operation is counted more than t0, to stop the compressor (S ₁ -11), it resets the count by the timer (S ₁ -12).

Subsequent pressure determination (S ₁ -13), the detected pressure Pd during the stop of the compressor drops below full load operation restoration pressure PL compressor is started again (S 1 _-14), pressure in the sensing pressure Pd determining (S ₁ -4) following operations are repeated.

  When a plurality of compressors 10 (101 to 103) are activated, the same operation is performed for each compressor.

Interlocking operation mode The operation flow of the compressed gas supply system 1 in the continuous operation mode with respect to the above-described single operation mode will be described with reference to FIGS. 3 and 4. alone - interlocking with the operating state by operating the changeover switch 31 was (S 1 _-1) interlocking operation mode, when the start switch 32 provided on the operation panel or the like of the unit count control device 30 to the oN (S 2 _-1) , The entire compressed gas supply system 1 is started, but at this time, only one of the first to third compressors (for example, the first compressor 101) is started to start full load operation (S ₂ − 2).

According to the detection signal of the interlocking operation control pressure detection means 21, the number control device 30 is configured such that the pressure in the collective tank 20 is (1) a pressure drop region, (2) a pressure lower limit region, (3) a pressure normal region, (4) upper pressure limit region, (5) determines whether the one of the state of the pressure increase region (S ₂ -3), in accordance with the determination result to control the compressors 10 (101 to 103) in a predetermined pattern.

One form of this control pattern will be described with reference to FIG. 4 (the parenthesis symbols correspond to FIG. 4).

(1) Pressure drop region The pressure Pd in the collective tank 20 detected by the pressure detection means for interlocking operation control 21 that detects the pressure in the collective tank 20 is indicated as (1) in the right column of FIG. When it is in the “region”, the next unit (second compressor 102 as an example) is started and fully loaded (S ₃ -1), and a predetermined start waiting time t1 (10 seconds as an example) is started. (S ₃ -2), a decision is made as to whether the start waiting time t1 has elapsed (S ₃ -3).

Further, the count of the start wait time t1, and determining the pressure in the collection tank 20 on the basis of the detection signal of the interlocking operation control for the pressure detecting means 21 (S ₃ -4), linked operations control pressure detecting means 21 detects pressure Pd of the collection tank 20 becomes equal to or larger than the set pressure LL before the expiration of starting wait time t1, the count start waiting time t1 is reset (S ₂ -7) described later pressure drop region (2) Shift to the control flow.

If the pressure Pd in the collective tank 20 is still less than the set pressure LL (for example, 0.57 MPa) even after the start waiting time t1 has elapsed, the next unit (for example, the third compressor 103) is further started to operate at full load. is (S ₃ -5), it resets the count of the starting wait time t1 (S ₃ -6), to start the count of the starting wait time t1 again (S ₃ -2), and repeats the subsequent similar operation.

  The start waiting time t1 is set to prevent a plurality of compressors from starting at the same time and causing a voltage drop in the power supply.

(2) Pressure lower limit area When the pressure Pd in the collective tank 20 detected by the interlocking operation control pressure detecting means 21 is in the “pressure lower limit area” shown as (2) in the right column of FIG. restores the charge of machine full load operation (S ₄ -1), starts counting a predetermined effect latency t2 (60 seconds for example) along with (S ₄ -2), or the effect latency t2 has elapsed determines whether (S ₄ -3).

Based on the detection signal of the interlocking operation control for the pressure sensing means 21, the pressure Pd in the collection tank 20 is compared with a predetermined set pressure (S ₄ -6), the pressure Pd in the collection tank 20, the effect latency t2 becomes equal to or larger than (0.60 MPa, for example) set pressure L before the expiration of, the count of the effect latency t2 is reset and proceeds to the control flow (S ₄ -7) pressure normal region (3), the detected pressure Pd There goes below LL, counting effects latency t2 is reset (S ₄ -7), the process proceeds to the control flow of the pressure drop region (1).

On the other hand, when the pressure Pd in the collective tank 20 is in the pressure lower limit region (2) (LL ≦ Pd <L) even after the effect waiting time t2 has elapsed, the next unit is further started (S ₄ -4), and resets the count of the wait time t2 (S ₄ -5), newly starts the counting of the effects latency t2 (S ₄ -2), and the above-described operation is repeated.

  The effect waiting time t2 is set in order to determine how the detected pressure changes due to the capacity control machine operating at full load, so that the compressor is not started unnecessarily.

  The control in the above pressure lower limit region (2) will be described by taking the compressed gas supply system 1 including three compressors 101 to 103 as shown in FIG. 8 as an example. When the detected pressure Pd reaches the lower pressure limit region (2) while the second and third compressors 102 and 103 are stopped in the responsible machine, the first compressor 101 is operated at full load, and the detected pressure Pd Is in the lower pressure limit region (2) even after the effect waiting time t2 has elapsed, the second compressor 102 is started.

(3) Normal pressure region When the pressure Pd in the collective tank 20 detected by the interlocking operation control pressure detection means 21 is in the “normal pressure region” shown as (3) in the right column of FIG. It is judged whether there is a compressor operating at no load (S ₅ -1). If there is a compressor operating at no load, all the non-load operating machines other than the capacity control machine are operated at full load. returns to (S ₅ -2), the current state is maintained when no compressors are idling.

  For example, in the configuration of the compressed gas supply system 1 shown in FIG. 8, the first compressor 101 is a capacity control machine, the first and second compressors 101 and 102 are operated without load, and the third compressor 103 is stopped. When the detected pressure Pd is in the normal pressure range of (3) in this state, the first compressor 101 continues the no-load operation and returns the second compressor 102 to the full load operation. When the first and second compressors 101 and 102 are operating at full load and the third compressor 103 is stopped, the current state is maintained.

(4) Pressure upper limit area When the pressure Pd in the collective tank detected by the interlocking operation control pressure detection means 21 is in the “pressure upper limit area” shown as (4) in the right column of FIG. There goes to no-load operation (S ₆ -1), 30 as the count of the no-load operation time with the start of the no-load operation is started (S ₆ -2), and, given the no-load operation time t3 (example elapsed seconds) is determined with (S ₆ -3), the pressure Pd in the collection tank 20 is compared with a predetermined set pressure (S ₆ -4).

When the pressure Pd in the collection tank 20 is equal to or higher than (0.70 MPa, for example) set pressure HH before the expiration of effects latency t3, the count of the no-load operation time is reset (S ₆ -7), ( 5) proceeds to the control flow of the pressure rise region of the pressure normal region of the detected pressure Pd is 0.67 MPa) than in the no-load operation time count reset as H (an example (S ₆ -7) (3) This is the control flow.

On the other hand, if the pressure Pd in the collective tank 20 is within the pressure upper limit region (4) (H ≦ Pd <HH) even after the no-load operation time t3 has elapsed, the capacity control machine moves to the next unit and no load is applied. stop the original capacity control charge machine is operating (S ₆ -5), the count of the no-load operation time is reset (S ₆ -6), reference characters 4 and FIG. 3 (B) (in the figure via circled symbol) Return to (S ₂ -3).

  Although slightly overlapping, in the pressure upper limit region (4), the capacity control machine sequentially shifts to no-load operation, the capacity control machine moves, and the original capacity control machine stops.

  For example, when the first to third compressors 101, 102, and 103 are all in full load operation, the first compressor 101 is in no load operation in the pressure upper limit region, and the second compressor 102 becomes a capacity control unit. . At this time, the second and third compressors 102 and 103 continue full load operation. When the no-load operation time t3 of the first compressor 101 elapses, the first compressor 101 stops.

  When the pressure in the collective tank 20 is still in the pressure upper limit region, the second compressor 102 is in a no-load operation and the third compressor 103 becomes a capacity control machine. At this time, the third compressor 103 continues full load operation. When the no-load operation time t3 of the second compressor 102 elapses, the second compressor 102 stops.

  Furthermore, if the pressure in the collective tank 20 is still in the pressure upper limit region, the first compressor 101 in which the third compressor 103 is stopped due to no-load operation becomes the capacity control machine, but the first compression The machine 101 continues to be stopped. When the no-load operation time t3 of the third compressor 103 elapses, the third compressor 103 stops.

  Further, as an example, the operation will be described with reference to the compressed gas supply system 1 shown in FIG. 8. For example, the first compressor 101 is a capacity control machine, and the first and second compressors 101 and 102 are operated at full load. When the detected pressure Pd reaches the pressure upper limit region (4) while the third compressor 103 is stopped, the first compressor 101 is shifted to the no-load operation, and the detected pressure Pd becomes the no-load operation time t2. If (30 seconds as an example) has passed and the pressure is in the upper pressure range of (4), the capacity controller is transferred to the second compressor 102 and the first compressor 101 is stopped.

(5) Pressure rise area When the pressure Pd in the collective tank 20 detected by the interlocking operation control pressure detecting means 21 is in the "pressure rise area" shown as (5) in the right column of FIG. all the compressor is operating shifts to no-load operation (S ₇ -1), then proceeds to the control flow (S ₆ -2) proceeds in the upper pressure limit region (4).

When the pressure rises abnormally The normal operation in the independent operation and the interlock operation in the compressed gas supply system 1 described above is the same as in the conventional compressed gas supply system 1 including the control mechanism described with reference to FIG. However, in the compressed gas supply system 1 of the present invention, the operation control device 40 of the compressor 10 (101 to 103) includes the second pressure setting unit 432, the second pressure determination unit 431, and the abnormality confirmation unit. The pressure abnormality determining means 43 consisting of 433 is provided, and the central control unit 35 of the number control device 30 operates in the operation control apparatus 40 of the compressor 10 based on the abnormality confirmation signal from the pressure abnormality determining means 43. The control signal for the mode switching means 42 is changed to a control signal for instructing the shift to the single operation so that it can be automatically switched to the single operation mode. It is configured (see FIG. 1).

  Such an emergency switching operation from the linked operation mode to the single operation mode will be described with reference to FIG.

When the operation in the interlocked operation mode is performed, the second pressure determination unit 431 provided in the operation control unit 40 of each compressor is configured so that the check valve 17 detected by the pressure detection unit 16 for independent operation control. the secondary pressure, i.e. the pressure in the collection tank 20 (see FIG. 9), it is determined whether the predetermined maximum set pressure Pmax or (S ₈ -1).

If the pressure in the collective tank 20 detected by the pressure detection means 16 for single operation control in the second pressure determination unit 431 is equal to or higher than the maximum set pressure Pmax, the time during which the pressure equal to or higher than the maximum set pressure Pmax is detected is counted. initiated (S ₈ -2), whether t4 predetermined abnormality confirmation time has elapsed it is determined (S ₈ -3).

If a pressure higher than the maximum set pressure Pmax (0.85 MPa as an example) is continuously detected for a predetermined abnormality confirmation time t4 (10 seconds as an example), the abnormality confirmation unit 433 detects an abnormality with respect to the unit control device 30. outputting a confirmation signal (S ₈ -4).

The central control unit 35 of the number control device 30 is in a state of waiting for an abnormality confirmation signal during operation of the compressed gas supply system 1 in the interlocked operation mode (S ₈ -5). An operation mode switching signal for instructing the operation control device 40 of the machine to release the interlock operation is output (S ₈ -6), and the anomaly display section 36 provided on the display panel of the number control device 30 is connected to the collective tank. Show pressure abnormality of 20 (S ₈ -7).

  On the other hand, when the second pressure determination unit 431 determines that the pressure in the collective tank 20 detected by the independent operation control pressure detection means 16 is less than a predetermined maximum set pressure Pmax, each compressor is in the interlocked operation mode. While the operation is continued, determination of the pressure detected by the single operation control pressure detecting means 16 is continued.

Even when the pressure in the collective tank 20 is equal to or higher than the maximum set pressure Pmax, the detected pressure in the collective tank 20 is the predetermined pressure even when the pressure detection means 16 for controlling the individual operation is detected. If the drops below the maximum set pressure Pmax prior to the expiration of the abnormal confirmation time t4, the abnormality confirmation time count is reset (S ₈ -8), is further continued determination of the pressure in the collection tank 20.

  The compressors that have been released from the linked operation and shifted to the independent operation are separated from the pressure detection means 16 provided in each compressor 10 (101 to 103) according to the operation flow of the single operation described with reference to FIG. The pressure determination is performed based on the detection signal, and the control signal for the intake control device 13 is output and the control signal for the drive control device 14 is output.

  Then, by setting the maximum set pressure Pmax to a pressure higher than the no-load operation start pressure PH, as described above, when the pressure in the collective tank 20 abnormally increases exceeding Pmax, each compressor 10 (101 to 103), the secondary pressure of the check valve 17 (the pressure in the collecting tank 20 (see FIG. 9)) detected by the pressure detection means 16 for independent operation control is the no-load operation start pressure. Since it is higher than PH, each compressor 10 (101 to 103) shifts to a no-load operation when it is in an independent operation, and stops the discharge of compressed gas.

  Accordingly, the unit control device 30 cannot recognize the pressure change in the collective tank 20 due to, for example, malfunction or failure of the interlocking operation control pressure detecting means 21, and therefore each compressor is shifted to no-load operation. Even if this is not possible, when the pressure in the collective tank 20 exceeds the maximum set pressure Pmax for a predetermined abnormality confirmation time t4, the operation control means 40 provided in each compressor shifts to no-load operation. Thus, the pressure in the collecting tank 20 is prevented from further rising.

  As a result, by setting the above-mentioned maximum set pressure Pmax to a predetermined low value with respect to the operating pressure of the safety valve 22 provided in the collective tank 20, for example, the safety valve 22 can blow or each compressor 10 ( It is possible to effectively prevent the emergency stop due to overpower of 101 to 103).

  As a result, for example, even when an operation failure or failure occurs in the interlocking operation control pressure detection means 21, the supply of the compressed gas to the consumption side can be continued without stopping, Along with the supply stop, it is possible to suitably prevent the production line or the like provided with, for example, an air working machine that is supplied with the compressed gas from the compressed gas supply system 1 from being stopped.

[Second Embodiment]
Next, another embodiment of the present invention will be described with reference to FIGS.

  In the compressed gas supply system 1 of the present embodiment, the pressure abnormality determination means comprising the second pressure setting unit 432, the second pressure determination unit 431, and the abnormality confirmation unit 433 in the operation control device 40 of each compressor 10 (101 to 103). The point that the abnormal rise of the pressure in the collective tank 20 can be determined by the pressure detection means 16 for independent operation control provided in each compressor 10 (101 to 103) is described above. The configuration of the compressed gas supply system 1 according to the first embodiment described with reference to FIGS.

  However, in the compressed gas supply system 1 of the first embodiment described with reference to FIGS. 1 to 5, the pressure abnormality determination means 43 provided in the operation control device 40 of the compressor 10 (101 to 103). Is temporarily input to the central control unit 35 of the number control device 30, and the central control unit 35 of the number control device 30 to which this abnormality confirmation signal is input is used for each compressor 10 (101 to 103). The operation mode switching signal for the operation control device 40 is switched from a signal for instructing the interlocked operation mode to a signal for instructing an independent operation. In the compressed gas supply system 1 of the present embodiment shown in FIG. 6, the operation control device 4 of the compressor 10 (101 to 103) is displayed. The abnormality confirmation signal output from the abnormality confirmation means 43 provided in the control unit 30 is transmitted to the central control unit 35 of the number control device 30, and is also transmitted to the operation mode switching means 42 provided in the operation control device 40 of the compressor 10, The drive control signal switching unit 421 and the intake control signal switching unit 422 of the operation mode switching unit 42 are controlled, and the drive control signal switching unit 421 and the intake control signal switching unit 422 that have input the abnormality confirmation signal are operated independently. The drive control signal and the intake control signal input from the control means 41 are output to the drive control device 14 and the intake control device 13.

  The abnormality confirmation signal output from the independent operation control means 41 of each compressor is also input to the central control unit 35 of the number control device 30, and the central control unit of the number control device 30 to which this abnormality confirmation signal is input. 35 is the same as the compressed gas supply system 1 described with reference to FIG. 1 in that the abnormality display unit 36 displays the pressure abnormality of the collective tank 20.

  The basic operation of the compressed gas supply system 1 of the present embodiment configured as described above is the same as the compressed gas supply system of the first embodiment described with reference to FIGS. .

  In the compressed gas supply system 1 of the second embodiment, when an operation failure or failure occurs in the interlocking operation control pressure detecting means 21, the number control device 30 cannot recognize the pressure increase in the collective tank 20, and accordingly, each compression The control signal for shifting the machine 10 (101 to 103) to the no-load operation cannot be output, and the pressure in the collective tank 20 starts to rise abnormally.

  As shown in FIG. 7, the pressure Pd detected by the independent operation control pressure detection means 16 is equal to or higher than the maximum set pressure Pmax (0.85 MPa as an example), and this pressure is detected as an abnormality confirmation time t4 (10 seconds as an example). When the operation is continued, the pressure abnormality determination means 43 outputs an abnormality confirmation signal to the operation mode switching means 42 to directly control the operation mode switching means 42.

  The operation mode switching means to which the abnormality confirmation signal is input is replaced with the output of the drive control signal and the intake control signal from the number control device 30 that has been output to the intake control device 13 and the drive control device 14 of the compressor. The drive control signal and the intake control signal input from the single operation control means 41 are output to switch the operation of each compressor to the single operation mode.

  The compressor that has been released from the linked operation and shifted to the single operation is controlled for each compressor according to the control flow described with reference to FIG. 2, but the compressor 10 (101 to 103) is independent. At the time of transition to operation, the pressure detection means 16 for independent operation control detects the maximum set pressure Pmax (0.85 MPa as an example), and the detected pressure Pd is higher than the no-load operation start pressure PH (0.70 MPa as an example). Since it is high, the single operation control means 41 outputs a control signal for shifting the compressor 10 (101 to 103) to no-load operation, and this control signal is sent to the intake control of the compressor via the operation mode switching means. Is output to the apparatus and the drive control apparatus, and the compressor shifts to a no-load operation.

  In addition, the abnormality confirmation signal is output from the operation control device to the number control device, and the number control device displays an abnormality on the abnormality display portion by inputting the abnormality confirmation signal.

  As described above, when the pressure in the collective tank 20 is abnormally increased, each compressor is operated in the single operation mode. Therefore, the pressure in the collective tank 20 is a predetermined high value with respect to the maximum set pressure Pmax. The operating pressure of the safety valve 22 that operates by pressure does not increase, and therefore the safety valve 22 does not blow.

  Further, in the configuration of the present embodiment, when the pressure in the collective tank 20 abnormally increases, the operation mode switching signal from the unit control device 30 is not waited for and the mode is changed to the single operation mode. In addition to being immediately suppressed, even when the interlock operation cannot be canceled due to a failure of the unit control device itself, the interlock mode can be canceled on the compressor side to shift to the single mode.

The block diagram of the control apparatus in a compressed gas supply system (1st Embodiment). Operation flow in single operation mode. Operation flow in linked operation mode (first half). Operation flow in the linked operation mode (second half). The operation | movement flow at the time of abnormal pressure rise (1st Embodiment). The block diagram of the control apparatus in a compressed gas supply system (2nd Embodiment). The operation | movement flow at the time of abnormal pressure rise (2nd Embodiment). Explanatory drawing which shows the whole structure of a compressed gas supply system. Schematic explanatory drawing of a compressor. The block diagram of the control apparatus in a compressed gas supply system (conventional).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Compressed gas supply system 10 Compressor 101 1st compressor 102 2nd compressor 103 3rd compressor 11 Compressor main body 12 Drive source (motor)
DESCRIPTION OF SYMBOLS 13 Intake control apparatus 131 Intake valve 132 Solenoid valve 133 Pipe line 14 Drive control apparatus 15 Receiver tank 16 Independent operation control pressure detection means (pressure sensor)
17 Check valve 18 Pipe line 20 Collecting tank 21 Pressure detection means (pressure sensor) for linked operation control
22 Safety valve 30 Number control device 31 Single-linked operation changeover switch 32 Start switch 33 Pressure determination unit 34 Pressure setting unit 35 Central control unit 40 Operation control device 41 Single operation control means 411 Start / stop switch 412 First pressure determination unit 413 1st Pressure setting section 414 Central control section 42 Operation mode switching means 421 Drive control signal switching section 422 Intake control signal switching section 43 Pressure abnormality determination means 431 Second pressure determination section 432 Second pressure setting section 433 Abnormality confirmation section

Claims (4)

Compressor body that compresses and discharges inhaled compressed gas, a drive source that drives the compressor body, an intake control device that controls opening and closing of an intake port of the compressor body, and a drive that controls the drive source A single operation control means for controlling the intake control device in accordance with a detection signal of the single operation control pressure detection means, and a control device and a single operation control pressure detection means for detecting the discharge side pressure of the compressor body A plurality of compressors each having
A collection tank common to the plurality of compressors for introducing the compressed gas discharged from the plurality of compressors and supplying the introduced compressed gas to the consumption side;
A number control device for controlling the intake control device and the drive control device of the plurality of compressors according to a predetermined pattern in response to a pressure change in the collective tank;
Providing pressure detection means for interlocking operation control for detecting the pressure in the collective tank and outputting it to the number control device;
The operation mode can be switched between an individual operation mode in which individual compressor control is performed by the individual operation control means and an interlocked operation mode in which the operation of a plurality of compressors is comprehensively controlled by the unit control device. As well as possible configuration,
During operation in the linked operation mode, when the pressure detection means for independent operation control provided in any of the compressors or a predetermined number of compressors detects a pressure higher than a preset maximum set pressure, the linked operation is performed. An operation control method for a compressor in a compressed gas supply system, wherein the operation mode is switched from the mode to the single operation mode.   2. The compressed gas supply system according to claim 1, wherein when the pressure detection means for single operation control detects a pressure equal to or higher than a maximum set pressure continuously for a predetermined time, the shift to the single operation mode is performed. Compressor operation control method. Compressor body that compresses and discharges inhaled compressed gas, a drive source that drives the compressor body, an intake control device that controls opening and closing of an intake port of the compressor body, and a drive that controls the drive source A single operation control means for controlling the intake control device in accordance with a detection signal of the single operation control pressure detection means, and a control device and a single operation control pressure detection means for detecting the discharge side pressure of the compressor body A plurality of compressors each having
A collection tank common to the plurality of compressors for introducing the compressed gas discharged from the plurality of compressors and supplying the introduced compressed gas to the consumption side;
A number control device for controlling the intake control device and the drive control device of the plurality of compressors according to a predetermined pattern in response to a pressure change in the collective tank;
It includes pressure detection means for interlocking operation control that detects the pressure in the collective tank and outputs it to the number control device,
The operation mode can be switched between an individual operation mode in which individual compressor control is performed by the individual operation control means and an interlocked operation mode in which the operation of a plurality of compressors is comprehensively controlled by the unit control device. An operation mode changeover switch is provided,
When operating with the changeover switch switched to the linked operation mode, the pressure detection means for independent operation control provided in any of the compressors or a predetermined number of compressors has a pressure higher than a preset maximum set pressure. A compressed gas supply system comprising an emergency switching means for switching the operation mode from the interlock operation mode to the single operation mode regardless of the selection of the interlock operation mode by the changeover switch.   The emergency switching means includes a counter for counting a pressure detection time equal to or higher than the maximum set pressure by the pressure control means for isolated operation control, and shifts to the isolated operation upon completion of a predetermined time count by the counter. The compressed gas supply system according to claim 3.

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