JPH06123287A - No-load operating device for engine compressor and stopping method - Google Patents

Abstract

PURPOSE:To provide a no-load operating device and stopping method for an engine compressor in which an engine and the compressor smoothly shift to a no-load operation and the engine and the compressor are stopped after they are fully cooled without closing an air cock, etc., which use of air is stopped. CONSTITUTION:When a switch 3 is turned on by stopping use of air, a solenoid valve 2 opens a piping 5, sending-out of compressed air from an oil chamber 14 is stopped by a pressure keeping valve 1 and a compressor 22 shifts to a no-load operation. A no-load operating time is measured by a measuring means such as a timer 32, etc., and an engine 2 is stopped after a predetermined time has passed. Thus, rapid stop of the engine 21 during a loaded operation of the compressor can be prevented, and reliability and life of the compressor 22 can be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a no-load operating device for an engine-driven compressor and a stopping method for the no-load operation.

[0002]

2. Description of the Related Art Although a motor is used as a drive source for a compressor, many drive sources are an engine. Compressed air from the compressor is separated into oil and air in the oil chamber,
The pressure-holding valve is pushed up and sent to the user side through the open air cock. The pressure-holding valve includes a valve that opens and closes a passage between the oil chamber side and the air cock, and a spring that presses the valve. When the pressure of the compressed air discharged from the compressor side exceeds the spring force, the valve of the pressure holding valve is pushed up to be sent to the use side via the air cock. On the other hand, when the use side stops using the compressed air, the air cock is closed. As a result, the capacity regulator and speed regulator operate, the intake air amount to the compressor and the engine speed decrease and drop, and no load operation starts, and the compressed air pressure in the oil chamber almost matches the spring pressure of the pressure-holding valve. Hold on to pressure. Next, the engine is stopped after the unloaded operation is continued for a certain period of time.

Even in a conventional engine compressor,
It is of course possible to immediately stop the engine from full-load operation of the engine, but this is not performed except when an emergency occurs. That is, the engine and the compressor are at high temperature and are operated at high pressure during full load operation.
Therefore, if the engine is suddenly stopped, it will be difficult to discharge the high-pressure and high-temperature air, which will result in impairing the function of each component, and the problems such as shortening the life of the components will occur. Therefore, in the prior art as well, a method has been adopted in which the engine and the compressor are sufficiently cooled before the engine is stopped after the no-load operation as described above.

[0004]

As described above, in the case of the prior art, the means for closing the air cock and starting the no-load operation when the use of air is stopped on the use side has been adopted. However, since the opening and closing of the air cock is performed manually, it is likely that the engine will be stopped by forgetting the closing operation of the air cock, and as described above, the sudden stop from the engine full load operation is likely to occur. Further, since the air cock cannot be fully closed without rotating several times, the opening and closing work thereof takes time and is troublesome. In addition, the time from fully loaded air cock, no load operation to engine stop becomes indefinite, and no load operation is continued more than necessary, or engine is stopped before engine and compressor are cooled sufficiently. Points are likely to occur.

The present invention solves the above problems, and provides a no-load operating device for an engine compressor that can easily enter into no-load operation without closing the air cock, and also provides a no-load operation device and an engine stop operation. The purpose is to provide a stop method.

[0006]

In order to achieve the above object, the present invention is driven by an engine and sends compressed air to a user side through an oil chamber, a pressure holding valve, an air cock and the like, and a capacity regulator. And a speed regulator, which is a no-load operating device for an engine compressor, and a pipe in which a spring chamber for accommodating a spring for pressing the valve of the pressure-holding valve to the oil chamber side and the oil chamber are provided with an electromagnetic valve. A no-load operating device which is connected by a road and is provided with a switch for turning on and off the solenoid valve, and further, in an engine compressor having the no-load operating device, the spring chamber side of the pressure holding valve and the oil chamber. Switch on the switch that engages the solenoid valve in the pipeline that connects with and when compressed air is not used , In which stop air supply to the consuming starts no-load operation, features a method of stopping the engine compressors so as to stop the engine manually or automatically after a predetermined time has elapsed.

[0007]

[Function] When the use of air is stopped on the use side, the switch is turned on. As a result, the solenoid valve operates, and the oil chamber side communicates with the spring chamber of the pressure holding valve. Therefore, even if the air cock is not closed, the valve of the pressure-holding valve closes the air outlet of the oil chamber by the spring pressure, and the air supply to the use side is stopped. A timer or the like is operated in association with the ON operation of the switch, and the engine is stopped manually or automatically after confirming the elapse of a certain time. As described above, the no-load operation and the subsequent engine stop can be performed safely and reliably.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram showing an overall configuration of a compressor to which the present embodiment is applied, FIG. 2 is a partial cross-sectional view showing a structure around a pressure-holding valve of the present embodiment, and FIG. 3 is a flow chart for explaining the operation of the present embodiment. Is.

First, the overall structure will be described with reference to FIG. Outside air is sucked into the compressor 22 driven by the engine 21 via an air cleaner 28 and an intake valve 27, and compressed air of appropriate pressure is discharged. Check valve 24 for compressed air
It is introduced into the oil chamber 14 through the discharge pipe 23 having the, and is separated into oil and air by the oil separator 15 and the like. The air from which the oil has been separated is sent to the use side 18 through the pressure holding valve 1 and the air supply pipe 16 provided with the air cock 17. On the other hand, the oil 20 separated and stored in the oil chamber 14 is returned to the compressor 22 side through the return pipe 25 having the cooling means 26 and is reused. A capacity regulator 30 is connected to the pressure-holding valve 1 side via a pipe 29, and a speed regulator 31 for controlling the engine speed is connected to the capacity regulator 30. A drain pipe 33 having a drain valve 19 is connected to the oil chamber 14 on the bottom side.

A pipeline 5 is connected to the pressure-holding valve 1 which is the main element of this embodiment, and a solenoid valve 2 is provided in the pipeline 5.
The solenoid valve 2 turns on and off the switch 3 that communicates with the power source 4.
The pipe line 5 is opened and closed by the operation. As shown in FIG. 2, the pressure-holding valve 1 mounted on the oil chamber 14 opens and closes the pressure-holding valve main body 6 and the air delivery port 8 on the oil chamber 14 side which is slidably supported in the pressure-holding valve main body 6. It comprises a valve 7, a spring 9 for pressing the valve 7 toward the air outlet 8, a spring chamber 10 in which the spring 9 is housed, and the like. An O-ring 13 is provided between the valve 7 and the pressure-holding valve body 6.
Is provided to prevent air leakage from this part. The upper side of the spring chamber 10 is closed by the upper lid 12. Further, the pressure-holding valve body 6 is internally provided with an air supply passage 11 which communicates with the air outlet 8 when the valve 7 is opened, and the air supply passage 11 communicates with the air supply pipe 16. A pipe line 5 is provided between the oil chamber 14 and the upper lid 12 to connect the inside of the oil chamber 14 and the spring chamber 10. An electromagnetic valve 2 is provided in the middle of the pipeline 5 to open and close the pipeline 5. Solenoid valve 2
Is turned on and off by a switch 3 connected to a power source 4.

Next, the operation of this embodiment will be described. During load operation of the compressor 22, the pressure of the compressed air sent from the oil chamber 14 exceeds the set pressure of the spring 9 of the pressure-holding valve 1, so the valve 7 is opened and the air outlet 8
And the air supply passage 11 communicate with each other. By opening the air cock 17, compressed air is sent to the use side 18 by the air supply pipe 16. In this case, the switch 3 engaged with the solenoid valve 2 is in the OFF state, and the conduit 5 is closed by the solenoid valve 2.

As shown in the flowchart of FIG. 3, when the use side 18 stops using the air (step 100), the switch 3 is turned on (step 101). This operation may be manual. When the switch 3 is turned on, the solenoid valve 2 is switched and the conduit 5 is opened. Therefore, a part of the compressed air in the oil chamber 14 is introduced into the spring chamber 10 through the pipe line 5 (step 102). Compressed air pressure in the oil chamber 14 acts on the valve 7 of the pressure-holding valve 1 via the air outlet 8, and the same compressed air pressure acts on the valve 7 as described above from the spring chamber 10 side, so that both are canceled. Therefore, the spring force of the spring 9 acts on the valve 7 to press the valve 7 in the direction of closing the air outlet 8. As a result, the pressure maintaining valve 1 is held in the closed state (step 103). When compressed air is further sent from the compressor 22 side with the pressure-holding valve 1 closed, the air pressure rises. The rising pressure is transmitted to the capacity regulator 30 via the pipe 29. As a result, the capacity regulator 30 restricts the intake valve 27 and limits the intake air amount.
At the same time, the air pressure is transmitted to the speed regulator 31 to rotate the engine 21 at a low speed. As described above, the no-load operation state is set (step 104). When no-load operation is started, time measurement is performed (step 105). The timer 32 may be used for time measurement as shown in FIG.
Further, another measuring means may be used. When a predetermined time for which the engine 21 and the compressor 22 are sufficiently cooled has passed, the engine 21 is stopped manually or automatically (steps 106 and 107). With the above operation, the air cock 17 is shifted to the no-load operation state without any opening / closing operation,
Moreover, the engine 21 and the compressor 22 can be stopped after a predetermined time has elapsed.

In this embodiment, the switch 3 is turned on and off.
Although the operation of the no-load operation is started by the FF operation, the use of compressed air may be detected and the series of operations according to the above-mentioned flowchart may be automatically controlled so as to be automatically performed.

[0014]

According to the present invention, the following effects can be obtained. (1) Since it is possible to smoothly shift to the no-load operation state without operating the air cock or the like when air use is stopped, the problem of suddenly stopping the engine without closing the air cock is completely eliminated. Thereby, the reliability and life of the compressor can be improved. (2) Since the engine and the compressor are stopped after they have cooled sufficiently after entering the no-load operation state, the functional deterioration of each part of the engine and the compressor can be prevented and the life can be improved. . (3) Only a small modification of the existing pressure-holding valve is required, and it can be easily and inexpensively attached to the existing compressor system.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a detailed structure around a pressure holding valve of the present embodiment.

FIG. 3 is a flowchart for explaining a method of no-load operation and stop of the compressor according to the present embodiment.

[Explanation of symbols]

 1 Pressure Holding Valve 2 Solenoid Valve 3 Switch 4 Power Supply 5 Pipe Line 6 Pressure Holding Valve Main Body 7 Valve 8 Air Outlet 9 Spring 10 Spring Chamber 11 Air Supply Passage 12 Upper Lid 13 O-ring 14 Oil Chamber 15 Oil Separator 16 Air Supply Pipe 17 Air Cock 18 Use Side 19 Drain valve 20 Oil 21 Engine 22 Compressor 23 Discharge pipe 24 Check valve 25 Return pipe 26 Cooling means 27 Suction valve 28 Air cleaner 29 Piping 30 Capacity regulator 31 Speed regulator 32 Timer 33 Drain pipe

Claims (2)

[Claims] 1. A no-load operating device for an engine compressor, which is driven by an engine, sends compressed air to a use side through an oil chamber, a pressure-holding valve, an air cock, and the like, and includes a capacity regulator and a speed regulator. A spring chamber that accommodates a spring that presses the valve of the pressure-holding valve to the oil chamber side is connected to the oil chamber by a pipe line that includes a solenoid valve, and a switch that turns the solenoid valve on and off is provided. A no-load operating device for an engine compressor. 2. An oil chamber driven by an engine,
A method of stopping an engine compressor having a capacity regulator and a speed regulator for controlling the intake air amount and the engine speed by sending compressed air to a use side through a pressure maintaining valve and detecting a pressure maintaining pressure and the like when the use is stopped, When the compressed air is not in use, the switch that engages with the solenoid valve in the pipeline that connects the spring chamber side of the pressure-holding valve and the oil chamber is turned on to stop the air supply to the operating side and perform no-load operation. A method of stopping an engine compressor, which is started and stopped manually or automatically after a lapse of a predetermined time.