JP4714554B2 - Reduction method of recovery time at momentary power failure in water circulation type compressor - Google Patents

Description

  The present invention relates to a method for shortening the recovery time at the momentary power failure in a water circulation compressor.

  As a water circulation type compressor, the one shown in FIG. 4 is a general configuration. That is, the air (outside air) that has passed through the air cleaner 7 is supplied to the compressor body 4 driven by the motor 5 through the air capacity adjustment valve 8. Further, lubricating water is supplied to the compressor body 4, and this lubricating water is supplied from the water supply unit 9 and the water 11 separated and stored in the receiver tank 10 is passed through a cooler 12 and a filter 6 and an electromagnetic valve. Some are supplied via 2. The compressed air compressed by the compressor is separated into air and water in the receiver tank 10, the air is sent to the air use side 13, and the separated water is collected in the receiver tank 10. A throttle valve 3 is provided in the water channel from the water supply unit 9.

  When a power failure occurs due to some reasons during operation, the motor 5 is naturally stopped, and at the same time, energization of each component of the compressor is stopped. Since the lubricating water is supplied to the compressor body 4 through the electromagnetic valve 2 as described above, the water supply stops at the time of a power failure, but is immediately supplied at the time of power recovery. The method of the present invention, which will be described later, is not applied in the case of a power outage for a long time. For example, in the case of a momentary power outage (instantaneous power failure) of about 0.2 seconds, there are the following problems.

When an instantaneous power failure occurs, the compressor main body 4 stops as described above, but when the instantaneous power failure is canceled, the compressor main body 4 attempts to start operation. However, it is necessary to release the residual pressure in order to restart when a momentary power failure occurs, and this operation takes several minutes. Furthermore, since the lubricating water is supplied at the time of power recovery, the lubricating water becomes excessive and it is difficult to restart.
On the other hand, the compressor use side wants the compressor to return to normal operation immediately after canceling the instantaneous power failure, but there is no method in the prior art.

Fig. 3 is a diagram showing the relationship between the time at the momentary power failure and return time and the (voltage, current, pressure, rotation speed) and the current, pressure, rotation speed takes a considerable time to return to normal. I understand. In addition, as a well-known technique regarding the instantaneous power failure of the compressor, for example, “Patent Document 1” can be cited, but it does not solve the above-described problem.
JP-A-6-249151 (summary)

  As described above, when a momentary power failure occurs, the conventional technique usually takes several minutes to return to normal operation even if power is restored. On the other hand, the compressor is an important compressed air supply means for the use side, and this long stoppage often causes great damage to the use side. Therefore, the use side strongly demands to return to normal operation immediately even if a momentary power failure occurs.

  The present invention has been invented in view of the above circumstances, and an object of the present invention is to provide a method for shortening the recovery time at the momentary power failure in a water circulation compressor capable of normal operation immediately after power recovery at the momentary power failure.

  In order to achieve the above-mentioned object, the present invention is characterized in that the time until the start of normal operation for a long time in power recovery after occurrence of an instantaneous power failure (hereinafter abbreviated as a momentary power failure) in a water circulation compressor is described. This method is characterized in that when an instantaneous power failure occurs, the supply of lubricating water is temporarily stopped corresponding to the instantaneous power failure time.

  Further, the invention of claim 2 is characterized in that, in the case where the instantaneous power failure time is a few tenths of a second, the lubricating water stop time is about 10 times that.

  According to the method for shortening the recovery time at the momentary power failure in the water circulation compressor according to claim 1 of the present invention, the compressor main body is normal without releasing the residual pressure by stopping the supply of the lubricating water for a predetermined time at the momentary power failure. It can be confirmed that the user will be able to fulfill the request from the user side.

  Further, according to the method for shortening the recovery time at the momentary power failure in the water circulation type compressor according to claim 2, when the momentary power failure time is about 1/10, if the supply stop time of the lubricating water is about ten times that It has been demonstrated that it returns to normal operation immediately.

Hereinafter, an embodiment of a method for shortening the return time at the momentary power failure in the water circulation compressor of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a configuration diagram for carrying out the method for reducing the recovery time at the momentary power failure in the water circulation compressor of the present invention, and shows a schematic configuration around the solenoid valve 2 in the overall configuration shown in FIG.

  As shown in FIG. 1, the electromagnetic valve 2 is provided with a control unit 1 for controlling ON / OFF. The control unit 1 opens and closes the electromagnetic valve 2 and the throttle valve 3, and the operation is performed in synchronization with ON / OFF of the supplied electricity. That is, when there is a momentary power failure, the control unit 1 is configured to control the solenoid valve 2 and the throttle valve 3 so as to close, and is determined corresponding to the momentary power failure time and released after the closing time. .

In this embodiment, the instantaneous power interruption time is 0.2 seconds, and the lubricating water stop time is 10 times that of 2 seconds. FIG. 2 shows a diagram corresponding to the diagram shown in FIG. 3 under these conditions. In FIG. 2, the horizontal axis represents elapsed time, and the vertical axis represents voltage, current, pressure, and rotational speed corresponding to time. As for the voltage, FIG. 2 is a constant voltage diagram as in FIG. 3, and the voltage is about zero at the momentary power failure time. It is not zero at all because of noise.
On the other hand, it can be seen that the current returns immediately after a slight delay from the momentary power failure compared to the conventional one in FIG. The pressure also drops due to momentary power interruption, but the pressure return position is far ahead compared to the prior art. In addition, it can be seen that the number of revolutions decreases extremely during a momentary power failure, but increases immediately and returns in a short time.

  Although the present invention operates as described above, it is needless to say that the instantaneous power interruption time and the lubricating water stop time are not limited to those described above.

  Although the present invention is applied to a water circulation type compressor, the type thereof may be arbitrary, and the range of use is wide.

The typical block diagram which shows the structure of a part of compressor for implementing the method of this invention. The diagram which shows the reset state of the voltage, electric current, pressure, and rotation speed at the time of the momentary power stop and power recovery by this invention. The diagram which shows the reset state of the voltage, electric current, pressure, and rotation speed at the time of the structure of the conventional compressor. FIG. 2 is a schematic overall configuration diagram of a general compressor.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Control part 2 Solenoid valve 3 Throttle valve 4 Compressor body 5 Motor 6 Filter 7 Air cleaner 8 Air capacity adjustment valve 9 Water supply part 10 Receiver tank 11 Water 12 Cooler 13 Air use side

Claims (2)

  A method for shortening the time until a normal operation start-up for a long time in power recovery after occurrence of an instantaneous power failure (hereinafter abbreviated as an instantaneous power failure) in a water circulation compressor, A method for shortening the recovery time at the momentary power failure in a water circulation compressor, characterized in that the supply of cooling water is temporarily stopped corresponding to the momentary power failure time.   The method for shortening the recovery time at the momentary power failure in the water circulation compressor according to claim 1, wherein when the momentary power failure time is 1 / several tenths of a second, the lubricating water stop time is about ten times that.

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