JP7777992B2 - foreign body suction device - Google Patents

Description

This disclosure relates to a foreign matter suction device for use inside a screw compressor to remove foreign matter that occurs when brine gets mixed into the refrigeration oil that lubricates the inside of the screw compressor.

Screw compressors are used in refrigeration systems such as refrigeration, freezing, and air conditioning equipment. A screw compressor is a device that compresses refrigerant gas by rotating a rotor. Refrigeration oil is filled inside the screw compressor to lubricate the rotor's rotation, and circulates within the screw compressor along with the refrigerant gas.

The brine cooler in a refrigeration system circulates low-temperature refrigerant gas inside the cooler, removing heat from the brine, which acts as an antifreeze, to cool the brine. In rare cases, the brine cooler can break, allowing the brine to enter the screw compressor. The brine is then stirred inside the screw compressor along with the refrigerant gas and refrigeration oil, forming a highly viscous, gel-like foreign substance that accumulates at the bottom of the screw compressor. The refrigerant gas inside the screw compressor can be recovered using a refrigerant recovery machine, but the gel-like foreign substance, a mixture of brine and refrigeration oil, remains inside the screw compressor.

Previously, removing gel-like foreign matter remaining in a screw compressor required an overhaul of the screw compressor, a process that required advanced skills and was time-consuming. Furthermore, in some cases, an on-site overhaul was not possible, requiring the screw compressor to be removed and the work carried out elsewhere, or the screw compressor itself to be replaced.

It is possible to remove the oil strainer or suction strainer from the screw compressor and suck up the foreign matter, but because the foreign matter is a highly viscous gel, it was not possible to suck it up sufficiently using a Hunt pump or electric pump. It was also not possible to suck up the fine details inside the screw compressor.

Patent Document 1 describes an air compressor for draining drainage that accumulates in the oil separator inside a screw compressor.

Japanese Utility Model Application Laid-Open Publication No. 6-58189

The air compressor in Patent Document 1 removes minute amounts of water mixed into the oil, but does not remove foreign matter created when refrigeration oil and brine are mixed together. Removing foreign matter from inside a screw compressor is a difficult and time-consuming task.

The purpose of this disclosure is to provide a foreign matter suction device for use inside a screw compressor that can easily remove foreign matter that occurs when brine gets mixed into the refrigeration oil that lubricates the inside of the screw compressor.

The foreign matter suction device for a screw compressor according to the present disclosure is a foreign matter suction device for a screw compressor that removes foreign matter generated when brine gets mixed into the refrigeration oil that lubricates the inside of the screw compressor. It includes a separation section for separating the foreign matter from the air, a suction device connected to the separation section that generates suction force, and a suction section connected to the separation section that sucks in foreign matter from inside the screw compressor. The separation section is characterized in that the suction device sucks in air from inside the separation section, thereby sucking in foreign matter from inside the screw compressor through the suction section.

The foreign matter suction device for use inside a screw compressor according to the present disclosure can easily remove foreign matter that occurs when brine gets mixed into the refrigeration oil that lubricates the screw compressor.

1 is a diagram illustrating the overall configuration of a foreign matter suction device inside a screw compressor according to the present disclosure. FIG. FIG. 2 is a detailed configuration diagram of a separation unit in a foreign matter suction device inside a screw compressor according to the present disclosure. 10A and 10B are diagrams illustrating a method of using a foreign object suction device for use inside a screw compressor according to the present disclosure. FIG. 1 is a diagram illustrating an outline of a cleaning method for a screw compressor. 1 is a schematic diagram of the overall configuration of a brine refrigerator system. FIG. 1 is a schematic diagram of an internal configuration of a screw compressor. FIG. 2 is a diagram illustrating the circulation paths of refrigerant gas and refrigerating machine oil inside the screw compressor. FIG. 1 is a diagram illustrating the generation of foreign matter inside a screw compressor.

Embodiments of the present disclosure will be described in detail below with reference to the drawings. In the following description, specific shapes, materials, directions, numerical values, etc. are examples intended to facilitate understanding of the present disclosure and can be modified as appropriate to suit the application, purpose, specifications, etc. Furthermore, it is anticipated from the outset that the components of the embodiments and variations described below may be selectively combined.

<Brine Refrigeration System>
First, the configuration of a brine refrigerator system 100 using a screw compressor 110 will be described with reference to Fig. 5. The brine refrigerator system 100 includes the screw compressor 110, a condenser 130, an expansion valve 140, and a brine cooler 150, and forms a refrigeration cycle.

The screw compressor 110 raises the pressure and temperature of refrigerant gas A, and the condenser 130 dissipates this heat into cooling water D, lowering the temperature of refrigerant gas A. The expansion valve 140 lowers the pressure and temperature of refrigerant gas A, and the brine cooler 150 absorbs the heat from brine C, lowering the temperature of brine C and, conversely, raising the temperature of refrigerant gas A. The refrigerant gas A that has absorbed the heat is taken back into the screw compressor 110 and compressed. By repeating this refrigeration cycle, the temperature of brine C is lowered, thereby controlling the temperature of freezers, refrigerators, and air conditioners.

<Screw compressor>
6 is a schematic diagram of the internal configuration of the screw compressor 110. The screw compressor 110 has a refrigerant gas suction port 111 that takes in low-pressure, low-temperature refrigerant gas A, and a refrigerant gas discharge port 112 that converts the refrigerant gas A into high-pressure, high-temperature refrigerant gas A and discharges it. As will be described later, the interior of the screw compressor 110 is filled with refrigerating machine oil B to lubricate the interior.

The screw compressor 110 further has a suction strainer 113 at the refrigerant gas suction port 111 that removes solid matter contained in the sucked refrigerant gas A. The screw compressor 110 also has an oil strainer 114 that removes solid matter contained in the refrigeration oil B circulating inside.

The screw compressor 110 has an induction motor 115, rotor 116, screw rotor 117, gate rotor 118, etc. as a compression mechanism for refrigerant gas A. The screw rotor 117 is fixed by a main bearing 119 on the axially opposite side of the induction motor 115 and a sub-bearing 120 located on the rotor 116 side.

The induction motor 115 is the power source for the screw compressor 110, and drives the rotor 116 and the screw rotor 117, which is formed integrally with the rotor 116 on an axis perpendicular to the rotor 116. The screw rotor 117 has spiral grooves on its circumference. A gate rotor 118 is attached to the axial side of the screw rotor 117, which engages with the grooved portion of the screw rotor 117 and rotates the screw rotor 117, compressing the refrigerant gas A.

In the screw compressor 110, the compressed refrigerant gas A and refrigeration oil B are separated into refrigerant gas A and refrigeration oil B in the oil separator 121, and only refrigerant gas A is discharged from the refrigerant gas discharge port 112, while refrigeration oil B circulates within the screw compressor 110.

The screw compressor 110 has a structure in which the screw rotor 117 and gate rotor 118 engage to compress the refrigerant gas A, so lubrication is required at the contact surfaces between the screw rotor 117 and gate rotor 118. Furthermore, to ensure that the screw rotor 117 rotates smoothly due to the induction motor 115, lubrication is also required for the main bearing 119 and auxiliary bearing 120. Although details are omitted, the gate rotor 118 also has a bearing that similarly requires lubrication.

As explained above, the screw compressor 110 is filled with refrigeration oil B, and a mixture of refrigerant gas A and refrigeration oil B circulates inside the screw compressor 110, lubricating each part.

Next, referring to Figure 7, the circulation paths of refrigerant gas A and refrigeration oil B inside the screw compressor 110 will be described. In Figure 7, the circulation path of refrigerant gas A is shown by a dotted line, and the circulation path of refrigeration oil B is shown by a dashed line.

Refrigerant gas A taken in through the refrigerant gas suction port 111 of the screw compressor 110 mixes with refrigeration oil B and travels through the induction motor 115 and auxiliary bearing 120 to lubricate the contact surfaces of the gate rotor 118 and screw rotor 117, before being separated into refrigerant gas A and refrigeration oil B in the oil separator 121.

Refrigerant gas A is discharged from refrigerant gas outlet 112 to condenser 130.

Refrigerant oil B passes through oil strainer 114, and some of it lubricates main bearing 119, while the remaining part passes through a hole that runs through the center of the shaft of screw rotor 117 to lubricate the induction motor 115. Refrigerant oil B that has splashed inside screw compressor 110 also lubricates the bearing of gate rotor 118.

As described above, refrigeration oil B constantly circulates inside the screw compressor 110, mixing with refrigerant gas A in some sections, lubricating each part.

Next, referring to Figure 8, we will explain a situation in which a malfunction of the brine cooler 150 causes brine C to enter the screw compressor 110, resulting in the generation of foreign matter E. The brine cooler 150 generally uses a shell-and-tube system, in which multiple tubes (pipes) are arranged inside a cylinder called a shell. Although rare, piping can burst inside the brine cooler 150. When a piping rupture occurs, brine C enters the low-pressure refrigerant gas A piping and enters the screw compressor 110 along with the refrigerant gas A. The brine C, refrigeration oil B, and refrigerant gas A that have entered the screw compressor 110 are mixed inside the screw compressor 110, becoming gel-like foreign matter E and accumulating at the bottom of the screw compressor 110.

While refrigerant gas A, which is a gas, can be recovered using a refrigerant recovery machine, a gel-like foreign substance E, which is a mixture of brine C and refrigeration oil B, remains inside the screw compressor 110. As mentioned in the conventional issues, removing this foreign substance E requires an overhaul of the screw compressor 110, but on-site overhaul work requires advanced skills and is time-consuming, making it often impossible to perform.

<Foreign object suction device inside screw compressor>
Next, the foreign body suction device 10 inside the screw compressor 110 of the present disclosure will be described with reference to Figures 1 and 2. Figure 1 shows the overall configuration of the foreign body suction device 10 inside the screw compressor 110, and Figure 2 shows the detailed configuration of the separation section 11 of the foreign body suction device 10 inside the screw compressor 110.

The foreign object suction device 10 comprises a separation section 11 for separating the sucked foreign object E from the air, a suction device 12 which is a vacuum pump that generates suction force, and a suction section 13 made of an elastic material such as a rubber hose that is inserted into the screw compressor 110 to suck up the foreign object E. The separation section 11, suction device 12, and suction section 13 are connected together by connecting fittings 22, copper pipes 18 and 19, rubber hoses, high-pressure hoses 21, etc. to form the entire device.

The separation section 11 has a cylindrical main body 14, a lid 15 that is tightly fitted to prevent air from entering the main body 14, an intake port 16 that is an opening in the lid 15, and an exhaust port 17 that is another opening in the lid 15.

The main body 14 of the separation unit 11 is constructed as a transparent container so that the state of the sucked foreign matter E can be visually observed from the outside. The main body 14 is formed, for example, from transparent glass. However, the main body 14 is not particularly limited and may be made of a material such as acrylic resin as long as it is transparent enough to allow the interior to be seen.

A first copper pipe 18 inserted into the main body 14 is connected to the suction port 16 of the lid 15. A second copper pipe 19 inserted into the main body 14 is connected to the discharge port 17 of the lid 15. The first copper pipe 18 is inserted further into the separation section 11, reaching near the bottom, than the second copper pipe 19. On the other hand, the second copper pipe 19 inserted on the discharge port 17 side is shorter than the first copper pipe 18, and is inserted so that one end protrudes slightly from the lid 15.

In this way, it is more effective to separate one end of the first copper tube 18 and one end of the second copper tube 19 inside the main body 14 in order to separate foreign matter E from air. In other words, since foreign matter E accumulates at the bottom of the main body 14, by separating one end of the second copper tube 19 from the bottom, foreign matter E does not bounce and adhere to the one end of the second copper tube 19, and foreign matter E does not get sucked in, and only the air can be sucked out.

Sealing material 20, such as a rubber bushing, is provided between the suction port 16 and the first copper pipe 18, and between the discharge port 17 and the second copper pipe 19 to prevent air from entering through the gaps. The sealing material 20 prevents air from entering during suction, which would reduce suction power.

The first copper pipe 18 and the suction unit 13 are connected by a connection joint 22. A high-pressure compatible hose 21 that can be used even at high pressures from the suction device 12 is connected to the second copper pipe 19 via the connection joint 22.

<How to use the foreign body suction device>
3, a method for using the foreign matter suction device 10 inside the screw compressor 110 of the present disclosure will be described. Note that the refrigerant gas A has been recovered in advance by a refrigerant recovery machine, and the remaining brine C and refrigerating machine oil B have been stirred to remove the gel-like foreign matter E.

To remove foreign matter E from inside the screw compressor 110, remove the suction strainer 113 from the refrigerant gas suction port 111 of the screw compressor 110, insert the suction part 13 of the foreign matter suction device 10 into the opening, and operate the suction device 12.

The inserted suction part 13 is moved up, down, left, and right to bring the tip of the suction part 13 into contact with the foreign matter E and suck it in. By checking the amount of foreign matter E being sucked into the main body part 14 at this time, it becomes easier to determine the location and presence of accumulated foreign matter E inside the screw compressor 110.

Next, remove the oil strainer 114, insert the suction part 13 into its opening, and similarly suck up the foreign matter E.

<How to clean the inside of a screw compressor>
Although the above-described method can remove most of the foreign matter E, it cannot completely remove it, so next, the inside of the screw compressor 110 is cleaned. Figure 4 shows an outline of the method for cleaning the inside of the screw compressor 110.

Washing oil F is injected at low pressure from the washing oil injector 23, a typical washing machine, through the opening after the suction strainer 113 and oil strainer 114 have been removed. Then, washing oil F is sprayed at high pressure from the washing oil hose 24 of the washing oil injector 23 to clean the area, and at the same time, foreign matter E is sucked up by the foreign matter suction device 10.

At this time, you can check the viscosity of the gel-like foreign matter E being sucked into the main body 14 and the amount sucked up, and see how much of the foreign matter E remains.

The above suction and cleaning are repeated until all foreign matter E inside the main body 14 has been removed, completing the removal of foreign matter E from inside the screw compressor 110.

The foreign object suction device 10 inside the screw compressor 110 of the present disclosure has a suction section 13 made of a flexible elastic material, so the tip of the suction section 13 can be pointed in various directions inside the screw compressor 110 to suck in foreign objects E. Furthermore, because the suction section 13 is made of a soft material such as a rubber hose, it will not damage the inside of the screw compressor 110.

The main body 14 of the separation unit 11 is made of a transparent material, so the condition of the suctioned foreign matter E and the amount sucked can be easily visually confirmed while performing the suction operation.

The suction device 12 uses a standard vacuum pump, so suction work can be easily performed by selecting a vacuum pump that corresponds to the required suction power.

As explained above, the foreign matter suction device 10 disclosed herein does not require on-site overhaul to remove foreign matter E that occurs when brine C enters the screw compressor 110, and does not require highly skilled workers; even ordinary workers can take action to quickly restore operation.

The present invention is not limited to the above-described embodiment and its variations, and various modifications and improvements are possible within the scope of the claims of this application.

10 Foreign matter suction device, 11 Separation section, 12 Suction device, 13 Suction section, 14 Main body, 15 Lid, 16 Suction port, 17 Discharge port, 18 First copper pipe, 19 Second copper pipe, 20 Sealing material, 21 High-pressure hose, 22 Connection joint, 23 Cleaning oil injector, 24 Cleaning oil hose, 100 Brine refrigeration system, 110 Screw compressor, 111 Refrigerant gas suction port, 112 Refrigerant gas discharge port, 113 Suction strainer, 114 Oil strainer, 115 Induction motor, 116 Rotor, 117 Screw rotor, 118 Gate rotor, 119 Main bearing, 120 Sub-bearing, 121 Oil separator, 130 Condenser, 140 Expansion valve, 150 Brine cooler, A Refrigerant gas, B Refrigerating machine oil, C Brine, D Cooling water, E Foreign matter, F Washing oil

Claims (5)

A foreign matter suction device for removing foreign matter generated in a screw compressor due to brine being mixed into refrigeration oil lubricating the inside of the screw compressor ,
the foreign matter suction device is provided independently of the screw compressor,
a separation unit for separating the foreign matter from air;
a suction device connected to the separation unit and generating a suction force;
a suction section connected to the separation section and configured to suck the foreign matter in the screw compressor ;
Equipped with
The separation unit is a foreign matter suction device in which the suction device suctions air in the separation unit, thereby suctioning the foreign matter in the screw compressor from the suction unit. The suction device is composed of a vacuum pump.
The foreign body suction device according to claim 1. The separation unit is
a main body formed of a transparent container;
a suction port to which the suction unit is connected;
an outlet to which the suction device is connected;
having
3. The foreign body suction device according to claim 1 or 2. the suction unit is connected to the separation unit by a first copper pipe;
the suction device is connected to the separation unit by a second copper pipe;
The first copper tube is inserted further into the separation section, closer to the bottom than the second copper tube.
The foreign body suction device according to any one of claims 1 to 3. the suction portion is formed of a tube made of an elastic material that is freely movable within the screw compressor.
The foreign body suction device according to any one of claims 1 to 4.