JPS61218788A - Automatic operation controlling system for compressed air feeding device - Google Patents

Abstract

PURPOSE:To make it possible to control the operation of a compressed air feeding device, effectively and safely, by controlling the operation of this device automatically according to detection signals of detectors for the elements which are necessary to control the operation of this device, such as air storage tank internal pressure, discharge pressure, and cylinder head air pressure. CONSTITUTION:The pressure in an air storage tank 1 is kept within the preset range of pressure, by a number of operating machines controlling means 43 whose input is the signals of a pressure detector 21 which detects the internal pressure of the air storage tank 1, and if the internal pressure rises abnormally, air compressors 4, 6, 8 are stopped by an abnormal high pressure protecting means 42 according to the detected signals of the pressure detector 21, before a safety valve 41 works on. The length of continued period of time of being lower than the preset pressure of the inside of the air storage tank 1, is measured by a continued period of time of pressure measuring means 44 whose input is detected signals of discharge pressure detectors 22, 23, 24 of the air compressors 4, 6, 8, and if the continued period of time of being lower than the preset pressure becomes longer than the preset value, an air compressor abnormality deciding means 45 decides corresponding one of the air compressors 4, 6, 8 to be abnormal, and stops this air compressor by a stop deciding means 46 according to the output of the means 45. In this way, effective and safe operation can be performed.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention operates multiple air compressors and automates the start/stop of a compressed air supply device that supplies compressed air, abnormality detection, and response to abnormalities. However, by performing appropriate operation control, a stable supply of compressed air can be ensured. This invention relates to an automatic operation control system for a compressed air supply device.

[Conventional technology]

Generally, when supplying a large capacity of compressed air to a factory work area, multiple air compressors are operated in parallel to ensure supply reliability and maintain the function and life of the air compressor. The compressed air on the discharge side is unified, stored in an air storage tank, etc., and supplied at a constant pressure. Compressed air supply devices are often used.

As a method of controlling the operation of this compressed air supply device, Fig. 4 shows
A method as shown in FIG. 5 is used.

In Fig. 4, +4), +6), 181 are air compressors, +51. (7).

(9) is the electric motor for the air compressor, (2) is the compressed air piping that passes through the check valve (3) that prevents the backflow of compressed air, and then the air storage tank (1).
)It is connected to the. I is a safety valve that is activated when the air pressure in the air storage tank (1) rises above the set pressure, and is made of a barrel that releases compressed air to the atmosphere. (93) is an automatic unloader valve installed in each air compressor.

Operated by the pressure of the cylinder head of each air compressor,
Continuous loading/unloading operation is performed. (11 is a power panel for air compressor electric a(51, (71, Connected. 0 is air compressor +41. +61. (
In the cooling water outgoing piping for cooling 81, I is the outgoing piping.

The cooling water is cooled in the cooling tower aυ, and the cooling water pump a'aF
c, and supplied to the air compressors (4), (61, (81).

It also returns to the cooling tower for circulation. (19 is the cooling tower fil
This is a pipe that supplies lk make-up water. A pressure switch (94) at the cooling water inlet of each air compressor sends a signal to the power panel al to stop the corresponding air compressor when the cooling water pressure falls below the set pressure.

Daily operation control is performed by the operation control panel (95),
An operation control signal is sent to the power panel to operate the compressed air supply device consisting of each air compressor, cooling tower αD, cooling water pump (12, etc.).

Next, in Fig. 5, (95) is the operation control panel, and the intermediate switches are manual switches (98) e electromagnetic relays (99),
It consists of control equipment such as a timer (100) and an electromagnetic time relay (101), and the control power supply (102) is connected to the input terminal (
105) and connect the control devices with electric wires (1OS) to form a control circuit, and the control device's electromagnetic contact activation signal is sent from the output terminal (107) to the control wiring (96
), the power panel (1 (HC is being sent). The power panel α0 receives the signal and activates each air compressor motor and cooling tower a.
υ.

Activate cooling water pump 0. (10B) is the power panel al
power supply wiring. (94) is a pressure switch located at the cooling water inlet of each air compressor.

Since the conventional compressed air supply system is configured as described above, in operation, first, the manual switch (98) in the operation control panel (95) is used to turn on the cooling water pump aL cooling tower f.
iυ is operated to circulate pressurized cooling water, and the stop signal of the pressure switch (94) at the cooling water inlet of each air compressor is released.

Next, the compressed air supply amount is predicted and the air compressor (4) (61
(Determine the number of operating units of 81, further determine the air compressor to operate as the main engine based on the total operating time, and turn on the corresponding manual switch (98) to begin operation. Air compressor in operation +41. [61, +810a The automatic unloader valve (93) performs continuous operation and unloading.

In addition, if the amount of compressed air supplied during operation changes, the number of units in operation can be increased or decreased using the manual switch (9B) K, depending on the situation. Air compressor in operation (41, (6), (8)
When an operation/maintenance engineer discovers a malfunction, he or she will use the manual switch (9B) of the relevant air compressor.

Cooling water pump (13, If the water pressure drops due to a supply water outage, etc., the air pressure m!41. (61, (8) will all stop. If you want to restart each stopped air compressor.

Before turning on the relevant manual switch (98), as a restart preparation work, open the manual valve (97) to release the residual pressure in the cylinder head of the air compressor you are about to start, and release the pressure in the cylinder head. It was set to zero.

[Problem that the invention seeks to solve]

The conventional method of controlling the operation of a compressed air supply device that operates multiple air compressors in parallel and supplies compressed air is as described above, in which the operation is controlled by the operator's switch operation. Selection.

Operations such as restart preparation were cumbersome, and there were concerns about incorrect operations.

In addition, there was a lack of quick response in the event of a failure of the air compressor, cooling water pump, etc., resulting in damage due to a drop in compressed air pressure or supply stoppage, and the old operation after failure was complicated and time-consuming. . On the other hand, the more devices that form a control circuit are controlled, the fewer operations required by operators, the more complicated the control circuit becomes.As a result, the operation control panel becomes larger, and the control circuit becomes more complex. There were problems such as an increased chance of failure and complicated maintenance.

In addition, the automatic unload valve of each air compressor is operated according to the amount of compressed air supplied, and the load/unload operation is performed, but even if compressed air supply is not required, unless the operator operates a switch to stop the compressor.

It was running continuously in an unloaded state, consuming unnecessary power.

This invention was made in order to improve these problems, and it automates the operation control of the compressed air supply device and improves the operation by converting the control circuit consisting of electromagnetic relays, timers, etc. into a logic circuit. Eliminates troublesome and erroneous operations, provides backup in case of failure, eliminates wasteful power consumption, and reduces the size of the operation control panel, increases reliability, and simplifies maintenance, making the compressed air supply system more efficient. The purpose is to obtain a safe and stable operation control method.

[Means for solving problems]

The automatic operation control method for a compressed air supply device according to the present invention includes a pressure detector that detects the pressure in an air storage tank, a means for controlling the number of operating units that maintains a predetermined pressure by inputting its detection signal, and an abnormally high pressure protection means. .

A pressure detector that detects the pressure at the air compressor discharge port, a means for measuring the duration of time when the pressure is below a predetermined level using the detection signal as input, and an abnormality determination for each air compressor that compares this duration with a set waiting time. With means.

A stop determination means that stops the operation of the air compressor according to the determination result, a pressure detector that detects the pressure of the cylinder head of each air compressor, and a pressure detector that uses the detection signal as input to load/unload the air compressor during operation. Load/unload determination command means for causing the operation to be performed; means for measuring the unload operation continuation time based on the unload determination command; and means for determining no load when this continuation time exceeds a set time; (9) power saving stop determining means for stopping the air compressor in question according to the determination result; and restart preparation means for restarting the stopped air compressor by the power saving stop determining means based on the output of the operating number control means. , a main unit switching means for multiple air compressors, a water temperature detector that detects an abnormal rise in the cooling water temperature of the water-cooled air compressor, a pressure detector that detects an abnormal drop in the cooling water pressure, and these two A means for inputting a detection signal and determining an abnormality in the cooling water.

A cooling water switching means for switching the cooling water based on the determination result is provided.

[Effect]

In this invention, the cylinder head of the air compressor corresponds to the compressed air path of the compressed air supply device.

The pressure of the discharge port and the storage tank is detected, and based on the detection signal, measurements and judgments are performed, and the number of operating units of multiple pneumatic machines is controlled, abnormal high pressure protection, and abnormal shutdown control of individual air compressors is performed. , a-do/unload operation switching control, stop control during no-load operation, restart preparation control after stop, and main engine switching control are organically combined.1. O Automatically controls the compressed air supply device that operates multiple air compressors in parallel and supplies compressed air. Also, detects the temperature and pressure of the cooling water of the water-cooled air compressor, and based on the detection signal, [Embodiment] Fig. 1 is an overall configuration diagram of an embodiment of a compressed air supply device according to the present invention. As is clear from FIG. 1, in this embodiment, 813 air compressors (41, (61, 2) is a compressed air pipe connected to the air storage tank (1) K via a check valve (3) that prevents backflow of compressed air. A pressure detection device that detects the air pressure inside the air storage tank (1) A pressure detector c111 is provided, and an air storage tank (
1) If the internal pressure is maintained within a predetermined range, and if the pressure rises abnormally, the abnormal high pressure protection means UK will send a
.

Air compressor +41. +63. Stop +81.

Air compressor +41. +611 (On the discharge side of 81, a pressure detector that detects the discharge pressure between the check valve (3) @,
a, Ga is provided, and this pressure sensor is +23.
The pressure duration measuring means lA41, which receives the detection signal from C14l, measures the duration of the pressure being below a predetermined pressure, and when the duration exceeds the set time, the air compressor abnormality determination means determines that the air compressor is +41. +6), 1B) The relevant air compressor among the three is determined to be abnormal, and based on its output, is stopped by the stop determining means.

Air compression e(41, (6), (81) are individually provided with pressure detectors (c), ■, and @ that detect the air pressure in the cylinders, and the detection signals of these pressure detectors (c) and town (■) are From the input a-do/unload judgment command means @nVc: i!!! Air pressure during rolling MUM (4>, (8),
(8) "k JCo -)" operation and unloading operation.The unloading operation continuation time measuring means which receives the output of this load/unloading judgment command means Qη as input)
When the unsigma rolling continuation time is measured and the continuation time exceeds the set time, the no-load judgment means θ9 indicates the corresponding air compressor among the air compressors +4), (6), +813 units. It is determined that there is no load on the air compressor, and the power saving stop determining means stops the corresponding air compressor based on the output.

Based on the way this power saving stop decision means comes out, the air compressor (
4), +61. +81 Individually provided solenoid valves for releasing residual pressure in the cylinder head (to), @, Among the 43 CBs, the corresponding solenoid valve opens and releases the residual pressure to the atmosphere, based on the output of the operating number control means. , Activate the restart preparation means (5) to prepare for restarting at any time.

1 Electric motor for air compressor (51, (7)
, +91 is supplied with power from the power panel αe by wiring (II).The power panel has the above-mentioned abnormal high voltage protection means as its control input.

The output of the means for controlling the number of operating units and the means for determining the stop due to air compressor abnormality is connected to the power saving stop determining means (to), and the input and output are connected to the main engine switching means (52). The main engine switching means (52) receives operation signals of the power supply circuits of the air compressor electric motors (5), (7), and (9), and the main engine switching means (52) counts the cumulative operation time of the main engine. , if the specified time is exceeded.

Designate the spare machine as the main machine, and make the conventional main machine the spare machine. This cycle is sequentially switched depending on the cumulative operating time.

Air compressor +41. +6! , +81, cooling tower a1+, cold water pump α2. Cold water outbound route ga
s, cooling water is circulated through cooling water return pipe +141. A pressure detector (g) and a water temperature detector are provided along the cooling water outgoing pipe α, and these two detection signals are input. If the cooling water abnormality determination means (53) determines that the water pressure is lower than the set water temperature and the water temperature is higher than the set water temperature, the cooling water switching means (54) is activated, the solenoid valve (9) connected to the cooling water outbound pipe α3 is opened, and the solenoid valve ( ) is closed, and the air compressor (4t, (
6+, (supplied to 81. At the same time, the cooling water return pipe +14
The solenoid valve (to) connected to 11c closes, and the solenoid valve opens and drains a? Configure a cooling water circuit that drains water to 1. Further, the operation of the cooling tower U and the cooling water pump a is stopped by the output of the cooling water switching means (54).

FIG. 2 is a circuit diagram showing the electrical connections of the embodiment of FIG. 1. In the figure, (55) is a sequencer.

opu (ss) * a C1 that has a mesori (57), an input unit (58), and an output unit (59)
1l-@, scold@, [Yes].

(2), (2), (to) are each pressure detector, (to) is a water temperature detector, and the output thereof is given to the input crab unit (58).

(29), Gl), 130. C (3,61+,
H, @, C*, m are solenoid valves, and the sequencer (55
) is connected to the kakanit (59), and the power panel Q
l) is similarly connected to the output unit) (59). Power panel αq is an air compression motor (5).

+7), (9), Cooling %Qn, 'liEm is supplied to the cooling water Hoy13. The power panel α1 is connected to the input crab unit (58) of the sequencer (55). (60) is a power supply for controlling the sequencer (55).

Next, the operation of the above embodiment will be explained with reference to FIG. 3, which is a flowchart showing the operation control program stored in the memory (57) of the sequencer (55).

First, in operation, by turning on the start switch of the sequencer (55), the air storage tank pressure (61) is determined. Storage tank lower limit pressure PL (e.g. 5.5-/
d) and the storage tank pressure FA, and if it is lower than the lower limit pressure PL, a main engine operation instruction is issued and the main engine operation starts (62).

If it is large, operation (65) becomes unnecessary. At the same time as turning on the start switch, the cooling tower and cooling water pump start operating (8
Enter 8).

If the air storage tank pressure FA is lower than the lower limit pressure PL even after starting the main engine operation (62), an operation instruction is issued to the standby engine [1] (
64)'s spare machine [1] goes into operation. The main engine continues to operate (
65). Furthermore, the air storage tank pressure PA is lower limit pressure P
If it is smaller than L, main engine operation continues (65), standby engine [1
] While continuing operation (66), an operation instruction is given to the standby machine [2], and the standby machine [2] (67) starts operating. 3 including the continued operation of the standby machine [2] (68) unless further instructions are given.
It is in a state of operation. The operating order is as above.

When the main engine starts operating (62), it starts counting the operating time (62).
9), and the cumulative driving time is set to a predetermined time To (for example, 150
(70)1. , issues an instruction (71) to switch the conventional main engine to the standby machine [2], the standby @[1] to the main engine, and the standby machine [2] to the standby machine [1]. The switching is performed sequentially for each To. For the above three units that are still in operation, the air storage tank pressure PA is equal to the air storage upper limit pressure pH (for example, 6.5 kg/
Determine whether d) has been reached (72) L spare machine [2],
An instruction to cancel operation (73) was issued for the backup engine [1] and then the main engine.

The process moves to each unloading pressure determination (74).

Unload pressure determination (74) detects the pressure in the cylinder head of each air compressor, and if the pressure is below P81 (0, for example, 6 kg/d), load operation (7s) is performed.

When P82 (for example, 7 kg/cd) or higher, an instruction to unload (76) is issued, and the
), the unload duration measurement starts as soon as the machine enters )
(77) Do. Judgment end time of unloading duration (
For example, 10 minutes) or not is determined (7B)L. If it is the determination end time, an instruction is issued for no load (79), and each corresponding air compressor is stopped (80). If the unsaid operation duration is less than the judgment end time.

At that point, it automatically resets to zero and prepares for the 9th unload operation.

When an operation instruction is given to each air compressor, the pressure at each air compressor discharge port is detected, and the pressure is set to a predetermined pressure (for example, 4.5k
g/d) or less (81).

In the following cases, start measuring the duration) (82)
let If the pressure does not fall below a predetermined level, the normal operating state is maintained. Determine whether the duration of the pressure being below a predetermined pressure is the determination end time (for example, 5 minutes) or not (83)1. , if it is the judgment end time, a failure instruction (84) is issued and the corresponding air compressor is stopped (80). If the duration of the pressure being below the predetermined pressure is less than the determination end time, it is automatically reset to zero at that point in preparation for the ninth signal below the predetermined pressure.

Air storage tank pressure PA is abnormally high pressure setting ajLPx (e.g. 8k
g/d) or more (85), an abnormally high pressure (86) protection instruction is issued and all air compressors in operation are stopped (80).

No load (79), failure (84) y abnormal high pressure setting (86
), the air compressor was stopped due to a busy command (80)t, and the residual pressure in the cylinder head of the air compressor was released, and restart preparations (87) were carried out to prepare for the first operation command. .

The start switch of the sequencer (55) is turned on and the cooling tower and cooling water pump are operated (88).

Detects pump abnormalities, cooling tower abnormalities, increases in cooling water temperature, and decreases in cooling water pressure due to supply water outages, etc.

Determine whether the water temperature exceeds a predetermined water temperature (for example, 45°C) (89) L. If it exceeds, immediately.

The cooling water is switched to another system (90), and the cooling tower and cooling water pump are stopped (91). Also, the cooling water pressure is set to the specified pressure (
For example, determine whether the weight is below 2.5 kg/d (92) 1. If it falls below, switch to another system of cooling water as above (90)? The cooling tower and cooling water pump are stopped (91).

Note that the above embodiment is an automatic operation control system for a number of air compressors. It is possible to replace the air compressor with other power delivery means, such as a water pump. For example, in a water supply system that operates multiple pumps, since the fluid has changed from gas to liquid, the main control input that used to be pressure detection can be changed to include flow rate detection.

In addition, the cooling water abnormality switching control can directly change the cooling equipment other than the air compressor, such as refrigeration equipment, to equipment where cooling water troubles are not allowed, such as conditioning equipment.

〔Effect of the invention〕

As described above, according to the present invention, a means for detecting elements necessary for operation control of the compressed air supply device is provided, and automatic continuous control can be performed based on the detection signal. Highly reliable, efficient, and safe driving control can be performed without complication and while avoiding inconveniences such as erroneous operation.

[Brief explanation of drawings]

FIG. 1 is an overall configuration diagram of an embodiment of a compressed air supply device according to the present invention, FIG. 2 is a circuit diagram showing its electrical connections, and FIG.
FIG. 4 is a flowchart showing its operation, FIG. 4 is an overall configuration diagram of a conventional pressurized air supply device, and FIG. 5 is a circuit diagram thereof. In the figure, +41. +61. (8) is an air compressor, 21. E. G, (goods), (c), (c), (5), (to) are pressure detectors, (2), ■. Gυ, (to), Cl3. (2), @, (to), (to)
, (company) is a solenoid valve, (to) is a temperature detector, (55)
is a sequencer. Note that the same reference numerals in Figure 9 indicate the same or corresponding parts.

Claims (2)

[Claims] (1) In a compressed air supply system that consists of multiple installed air compressors powered by AC motors, piping that conveys the compressed air generated by the air compressors, and an air storage tank that stores the compressed air, A pressure detector for detecting the air pressure in the air storage tank, a means for controlling the number of operating units that receives a detection signal from the pressure detector and maintaining a predetermined pressure, and an abnormally high pressure protection means. Also, a pressure detector that detects the air pressure at the discharge port of each air compressor installed in multiple units, a means for measuring the duration of time when the pressure remains below a predetermined level using the detection signal of this pressure detector as input, and setting this duration time. Abnormality determining means for determining the abnormality of each air compressor by comparison with time, stop determining means for stopping the operation of the air compressor according to the output of this abnormality determining means, A pressure detector that detects the air pressure in the cylinder head, a load/unload judgment/command means for inputting the detection signal of this pressure detector to load and unload the air compressor during operation, and this loading/unloading. Means for measuring the duration of unloading operation based on the output of the determination/command means; means for determining no load when this duration exceeds a set time; and based on the determination. The power saving stop determining means stops the air compressor to save power, and the power saving stop determining means restarts the stopped air compressor based on the output of the operating number control means, so the pressurized air inside the cylinder head is used. and a main engine switching means that sequentially switches the air compressor operating as the main engine at a certain period of time in order to equalize the operating time, operating history, etc. of multiple air compressors. An automatic operation control system for compressed air supply equipment featuring: (2) When using water to cool the air compressor, a water temperature detector detects an abnormal rise in the cooling water temperature, and a pressure detector detects an abnormal drop in the cooling water pressure.Based on the detection signal, the cooling water is Claim No. 1 characterized in that a cooling water abnormality determining means for determining an abnormality, and a cooling water switching means for automatically switching a cooling water system to a water system of another system according to the cooling water abnormality determining means are provided. ) An automatic operation control system for the compressed air supply device described in item 2.