JPS6243078B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for adjusting capacity of a compressor. That is, an object of the present invention is to accurately detect the pressure within the receiver tank and to accurately adjust the capacity of the compressor based on the detected pressure. Its features are: firstly, the operating pressure of the pneumatic unloader is controlled by the compression pressure before the receiver tank passes through the separator; and secondly, the regulator uses Compression pressure is introduced separately into the regulator, and a valve mechanism is provided to open and close the compression pressure passage after passing through the separator, which operates the pneumatic unloader. It is located in a device that is connected to the piping so that it is linked to the advancing and retracting mechanism that operates.

As shown in FIG. 1, conventional compressor capacity adjustment includes a pneumatic unloader 10 connected to the suction port of the compressor, and a regulator 20 connected to the unloader 10.
A receiver tank 30 is connected to the receiver tank 30 by piping, and a chamber 21 of the regulator 20 is connected to a discharge pipe of a separator 31 built into the receiver tank 30, and the discharge pressure of the receiver tank 30 is always applied to the chamber 21. Further, the chamber 22 of the regulator 20 is connected to the compartment 11 of the unloader 10, an orifice 12 is bored in the compartment 11, and a receiver tank 30 is installed in the compartment 11 so that the entire device operates smoothly. The compressed air supplied from the compressor via the regulator 20 is discharged through the orifice 12 to the suction port 1 of the compressor. Further, a diaphragm 24 having a spring 23 in the chamber 21 of the regulator 20 adjusts the opening degree of the needle valve 25, and adjusts the amount of compressed air that is the operating pressure of the unloader 10 and passes from the chamber 21 to the chamber 22. However, if the amount of air used from the receiver tank 30 is smaller than the amount of discharge air compressed by the compressor and the discharge pressure, that is, the pressure in the chamber 21, exceeds a certain value, the pressure of the compressed air acting on the diaphragm 24 will decrease. Overcoming the tension of the spring 23, the diaphragm 24 is pushed up to the left, the needle valve 25 is released from the seat, and compressed air flows from the chamber 21 to the chamber 22, and from the chamber 22 passes through the pipe 13 to the compartment 11 of the unloader. enter.
When the amount of air used further decreases and the degree of opening of the needle valve increases, the amount of compressed air at operating pressure entering the compartment 11 from the chamber 22 increases, and the pressure rise in the compartment 11 causes the diaphragm 14 to close to the valve 15 of the unloader 10. Press to throttle the intake air of the compressor. When the amount of air used further decreases, the pressure inside the receiver tank 30 increases, so that the unloader valve 15 is completely pressed against the seat 16, and the compressor does not take in any air and becomes in a no-load state.

When the amount of air used increases, the opening degree of the unloader valve 15 increases, contrary to the above, and the amount of intake air increases. Although not particularly shown, in an engine-driven compressor, operating pressure is also supplied to the actuator of the governor lever in order to increase or decrease the engine speed in accordance with the opening degree of the unloader valve. The compartment 11 of the unloader is connected to the discharge pipe of the separator via a pressure reducing valve, and a load is always applied to the unloader valve 15 to keep it open.

In this way, conventional capacity control uses the regulator 20.
Introducing the discharge pressure that has passed through the separator 31 from the discharge pipe of the separator 31 of the receiver tank 30,
The pressure in the receiver tank 30 is detected using the discharge pressure, and at the same time, compressed air corresponding to the detected pressure is introduced into the compartment 11 having the orifice 12 of the unloader 10 to serve as the operating pressure of the unloader valve 15.
Therefore, if oil adheres to the separator 31 of the receiver tank 30 and it becomes clogged, the pressure inside the receiver tank will decrease due to the pressure loss passing through the separator.
The pressure before passing through the separator 31 is higher than after passing through, and the unloader does not operate even though the pressure in the receiver tank has reached a pressure that requires capacity adjustment. That is, with conventional control means that uses the pressure after passing through the separator as the detection pressure, the unloader cannot accurately follow the actual pressure inside the receiver tank, and at the same time, the rotation of the engine or motor cannot be adjusted appropriately. Overload of the motor, damage to the receiver tank, deterioration of lubricating oil due to overheating of the compressor as the compression ratio increases, and overload due to an increase in the amount of circulating lubricating oil due to the increase in compressor discharge pressure. Defects such as oil locks occurred.

The fundamental cause of such defects is that the pressure detected by the regulator is the compressed air that has passed through the separator of the receiver tank. Therefore, the detected pressure may be the compressed air before passing through the separator, but since a large amount of oil is mixed in the compressed air before passing through the separator, oil adheres not only to the regulator but also to the unloader. Because the viscosity significantly impedes the functions of both, conventional capacitance adjustment has not been able to extract the detected pressure before it passes through the separator.

The present invention was developed to solve the fundamental defects of the conventional capacity adjustment means described above, and details thereof will be explained below based on the illustrated embodiments.

In FIGS. 2 and 3, 40 is a pneumatic unloader, 50 is a regulator, and 70 is a receiver tank.

The regulator 50 has a detection chamber 51 that is provided at a position higher than the oil level of the receiver tank 70 and is connected to a pipe 72 that is connected to the receiver tank 70 before passing through a separator 71. will be introduced. Further, a piston 52 sliding in the chamber 51 is locked to one end of a spring 53, and the other end of the spring 53 is locked to the tip of a bolt 54, and by screwing the bolt 54, the piston 52 It is provided so that the pressing force against it can be adjusted. Further, the tip of the piston 52 has a needle valve 56 and is provided to freely open and close a communication hole 60, which will be described later, via the side wall 55 of the detection chamber 51. That is, one side opening 61 of the communication hole 60 is connected to the discharge pipe of the separator 71 of the receiver tank 70 through the pipe 73 so as to introduce compressed air, which is the working pressure after passing through the separator 71 of the receiver tank 70. ing. On the other hand, the other side opening 62 of the communication hole 60 is connected to a compartment 42 having an orifice 41 of the pneumatic unloader 40 via a pipe 43, and compressed air after passing through the separator 71 is introduced into the unloader 40 via the regulator 50. do. Further, a needle valve 56 provided at the tip of the piston 52 faces the inner periphery of the opening 62 of the communication hole 60 so as to be freely inserted and removed, and the opening 62 is configured to be openable and closable.

Although the unloader 40 has a slightly different structure from the one shown in FIG. 1, it is the same as an intake block type unloader called a pneumatic unloader. That is, the piston 44 is connected to the operating rod 45 and slides within the compartment 42 by the compressed air that has passed through the separator 71 of the receiver tank 70 and is introduced into the compartment 42 via the pipe 43, and the unloader valve 46 Open and close. An orifice 41 discharges compressed air, which is the operating pressure of the unloader 40 introduced into the compartment 42, to an inlet of a compressor (not shown). This orifice 41 allows the entire device to operate smoothly, and together with the regulator 50, it is possible to arbitrarily adjust the operating pressure of the unloader valve 46. Further, 47 is a spring, which also adjusts the operation of the unloader valve.

Incidentally, as shown in FIG. 3, a pipe 74 is provided, and the detection chamber 5 of the regulator 50 is connected through the pipe 74.
1 and before passing through the separator 71 in the receiver tank 70, and the regulator 50 is provided at a position higher than the oil level of the receiver tank 70, so that the compressed air is separated from the detected pressure introduced into the detection chamber 51 of the regulator 50. The structure is such that the oil is returned to the receiver tank 70.

Additionally, if the pipe 72 for introducing detection pressure into the detection chamber 51 of the regulator 50 is connected to the lower part of the detection chamber 51, this pipe 74 becomes unnecessary.
This is because the oil accumulated in the detection chamber 51 is collected into the receiver tank via the pipe 72. Further, in the above embodiment, the regulator 50 and the unloader 40 have a piston 52 structure, but are not limited to this, and may have a diaphragm structure.

In addition, in FIG. 3, 75 is a pipe communicating with the discharge port of the compressor, 76 indicates the recovered lubricating oil, and 77 indicates a safety valve. Also, in Figure 2, 5
7 is an O-ring.

The present invention consists of the above configuration, and its operation will be explained below.

In the figure, the white arrows indicate the flow of intake air (fluid) to the compressor, the solid line arrows indicate the flow of compressed air before passing through the separator 71 of the receiver tank 70, which is the detected pressure, and the dashed-dotted line arrows indicate the flow of air (fluid) into the compressor. The flow of compressed air after passing through a pressure separator is shown.

Compressed air is now being discharged from the compressor and being fed to the receiver tank 70 via the pipe 75.
A desired amount of compressed air can be used from an air tank (not shown) via a safety valve 77.

The pressure within the receiver tank 70 is introduced into the chamber 51 of the regulator 50 via the pipe 72,
The discharge pressure within the receiver tank 70 always acts on the chamber 51, and the piston 52 detects the discharge pressure. On the other hand, the pressure after passing through the separator 71 is transferred to the communication hole 60 of the regulator 50 from the pipe 7.
3 through the opening 61. now,
When the amount of compressed air used in the receiver tank 70 decreases, the pressure in the receiver tank 70 increases,
For example, when the pressure exceeds 7 kg/cm ² , the piston 52 of the regulator 50 moves to the right in FIG. 3 against the pressure of the spring 53. Accordingly, the needle valve 56, which is inserted into the opening 62 of the communication hole 60 through the side wall 55 and has been closing the opening 62, also moves to open the opening. On the other hand, the compressed air after passing through the separator 71 is introduced into the communication hole 60 from the opening 61, and by opening the opening 62 of the communication hole 60, the compressed air (dotted chain arrow) serving as the operating pressure is introduced into the unloader. 40 compartments 42. When the opening degree of the needle valve 56 increases, the communication hole 6
The amount of compressed air that is the operating pressure passing through 0 also increases, and the piston 44 of the unloader 40 moves against the pressing force of the spring 47, pushing the unloader valve 46 and reducing the amount of intake air (white arrow). When the amount of air used decreases further, the pressure of the compressed air before passing through the separator, which is the detection pressure, increases, and the needle valve 56 opens further, and finally the unloader valve 46 is closed and the compressor does not take in any air and becomes unloaded. In the case of an engine-driven compressor, the actuator simultaneously moves the governor lever and the engine speed is reduced to its minimum speed.

In the above embodiment, the pneumatic unloader 40 has a piston structure, but it may optionally have a diaphragm structure together with the regulator. Further, the piston 44 of the unloader 40 is equipped with a spring 47, but instead of the spring 47, compressed air is introduced into the compartment 48 through a pressure reducing valve through a pipe 73, thereby restricting the movement of the unloader valve 46. You can do it like this.

The present invention has the above-described structure and operation, and the pressure of the receiver tank before and after passing through the separator is introduced into the regulator, and the pressure after passing through the separator is introduced into the pneumatic unloader to operate the unloader. Since this method controls the amount of operating pressure introduced by the detected pressure before passing through the separator, it can be applied even when the separator is clogged without impairing the functions of the regulator or pneumatic unloader. It is possible to accurately detect the pressure inside the receiver tank, and based on this detected pressure, the pneumatic unloader can be operated accurately at any pressure value, preventing motor overload operation and abnormal pressure inside the receiver tank. Defects such as tank damage due to lift, deterioration of lubricating oil due to compressor overheating due to increased compression ratio, overload due to increased amount of circulating lubricating oil due to increased discharge pressure, and defects such as oil lock. It can be prevented. In addition, a communication hole and a valve mechanism that can freely open and close the communication hole are provided in the regulator, and after passing through the separator of the receiver tank, one of the communication holes is connected to the compartment of the pneumatic unloader by piping. Further, an advancing/retracting mechanism such as a piston is provided in the detection chamber provided through the communication hole and the compartment, and the detection chamber is connected with piping before the receiver tank passes through the separator, and the advancing/retracting mechanism and the valve mechanism are connected. Therefore, it has become possible to detect the pressure before passing through the separator, and use this detected pressure to make the pressure after passing through the separator the operating pressure for operating the pneumatic tick and unloader.

Therefore, it is possible to detect the pressure value in the receiver tank more accurately than conventional regulators and operate the unloader. Also, even if the separator becomes clogged, the unloader can be operated properly and abnormalities in the receiver tank can be detected. It is possible to prevent a pressure increase and enable stable operation of the compressor, making it possible to prevent the above-mentioned defects due to clogging of the separator.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing capacity adjustment of a conventional compressor, and FIGS. 2 and 3 show an embodiment of the present invention. 40...New machine unloader, 41...
Orifice, 42... Compartment, 46... Unloader valve, 47... Spring, 50... Regulator, 51... Detection chamber, 52... Piston, 53
... Spring, 55 ... Side wall, 60 ... Communication hole, 61, 62 ... Opening, 70 ... Receiver tank, 71 ... Separator, 43, 72, 73 ...
...pipe, 76...oil.

Claims (1)

[Scope of Claims] 1. A compressor comprising a pneumatic unloader connected to the suction port, a receiver tank connected to the discharge port, and the pneumatic unloader connected to the receiver tank containing a separator via a regulator. In this step, the pressure of the receiver tank before and after passing through the separator is introduced into the regulator, and the pressure after passing through the separator is introduced into the pneumatic unloader to be the operating pressure of the pneumatic unloader, and the pressure of the receiver tank is A method for adjusting the capacity of a compressor, characterized in that the amount of the operating pressure introduced into the pneumatic unloader is controlled using the pressure before passing as the detected pressure. 2. A compressor in which a pneumatic unloader is connected to the suction port, a receiver tank is connected to the discharge port, and the pneumatic unloader is connected to the receiver tank containing a separator via a regulator, the regulator: It has a communication hole and a valve mechanism that can freely open and close the communication hole, one of the communication holes is connected to the receiver tank after passing through the separator, and the other is connected to the compartment of the pneumatic unloader, and the other is connected to the compartment of the pneumatic unloader. A reciprocating mechanism such as a piston or a diaphragm is provided in the detection chamber provided through a partition in the communication hole, the detecting chamber is connected to the piping before the receiver tank passes through the separator, and the reciprocating mechanism is connected to the valve mechanism. Features: Compressor capacity adjustment device.