CN111577607A - Check valve and rotor compressor - Google Patents
Check valve and rotor compressor Download PDFInfo
- Publication number
- CN111577607A CN111577607A CN201910122845.0A CN201910122845A CN111577607A CN 111577607 A CN111577607 A CN 111577607A CN 201910122845 A CN201910122845 A CN 201910122845A CN 111577607 A CN111577607 A CN 111577607A
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- China
- Prior art keywords
- inner cavity
- valve
- check valve
- air outlet
- air inlet
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
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Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C29/00—Component parts, details or accessories of pumps or pumping installations, not provided for in groups F04C18/00 - F04C28/00
- F04C29/12—Arrangements for admission or discharge of the working fluid, e.g. constructional features of the inlet or outlet
- F04C29/124—Arrangements for admission or discharge of the working fluid, e.g. constructional features of the inlet or outlet with inlet and outlet valves specially adapted for rotary or oscillating piston pumps
- F04C29/126—Arrangements for admission or discharge of the working fluid, e.g. constructional features of the inlet or outlet with inlet and outlet valves specially adapted for rotary or oscillating piston pumps of the non-return type
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C29/00—Component parts, details or accessories of pumps or pumping installations, not provided for in groups F04C18/00 - F04C28/00
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Check Valves (AREA)
Abstract
The invention provides a check valve and a rotor type compressor, and belongs to the technical field of compressors. The check valve comprises a valve core and a valve seat; the valve seat is provided with an inner cavity along a first direction, and the included angle theta between the first direction and the horizontal plane is more than 0 degree and less than or equal to 90 degrees; the valve core is arranged in the inner cavity in a sliding manner and divides the inner cavity into a first inner cavity and a second inner cavity from top to bottom along the gravity direction; the valve seat is provided with an air inlet and an air outlet which are communicated with the second inner cavity, and when the pressure of the air inlet is less than or equal to the pressure of the air outlet, the valve core is positioned in the second inner cavity, so that the air inlet is not communicated with the air outlet; when the pressure of the air inlet is higher than that of the air outlet, the valve core moves towards the direction of the first inner cavity, so that the air inlet is communicated with the air outlet. Because the spring of the check valve in the prior art is eliminated, the reliability of the check valve is not limited by the spring any more, and the reliability of the check valve is improved.
Description
Technical Field
The invention relates to the technical field of compressors, in particular to a check valve and a rotor type compressor.
Background
The rotor compressor is widely used in electrical equipment such as air conditioners, refrigerators and the like, and the volumetric efficiency of the compressor is one of the main parameters for evaluating the performance of the compressor.
At present, in order to improve the volumetric efficiency of the rotor compressor, a check valve is generally installed in the compressor with an injection technology structure or an air-supply enthalpy-increasing structure, and the check valve can reduce the backflow of the refrigerant, thereby increasing the volumetric efficiency of the compressor. A check valve in the prior art is generally shown in fig. 1 and 2, and comprises a base 1, a valve core 2, a return spring 3 and a component 4 for stroke limitation and connection, wherein the check valve can effectively reduce backflow of refrigerant from an air outlet 6 to an air inlet 5; the refrigerant usually contains gas and liquid, and the refrigerant flows to the gas outlet 6 through the through-flow channel, and in order to increase the area of the through-flow channel, a plurality of through-flow grooves 7 need to be processed on the inner side of the base or the outer diameter of the valve core, so that the refrigerant smoothly flows to the direction of the gas outlet 6.
However, the check valve in the prior art has at least the following problems: the check valve in the prior art relies on a large degree of a spring, but the spring is easily damaged due to frequent compression and extension, resulting in low reliability of the check valve.
Disclosure of Invention
The invention provides a check valve and a rotor type compressor, which are used for improving the reliability of the check valve.
To achieve the above objects, the present invention provides a check valve,
the check valve comprises a valve core and a valve seat;
the valve seat is provided with an inner cavity along a first direction, and an included angle theta between the first direction and a horizontal plane is more than 0 degree and less than or equal to 90 degrees;
the valve core is arranged in the inner cavity in a sliding mode and divides the inner cavity into a first inner cavity and a second inner cavity from top to bottom along the gravity direction;
the valve seat is provided with an air inlet and an air outlet which are communicated with the second inner cavity, and when the pressure of the air inlet is less than or equal to the pressure of the air outlet, the valve core is positioned in the second inner cavity, so that the air inlet is not communicated with the air outlet; when the pressure of the air inlet is larger than the pressure of the air outlet, the valve core moves towards the direction of the first inner cavity, so that the air inlet is communicated with the air outlet. Optionally, a communication channel is further formed in the valve seat, and the communication channel is used for communicating the first inner cavity with the air outlet.
Optionally, the first inner cavity penetrates through the valve seat in a direction away from the second inner cavity to form a through hole, and a sealing plug for sealing the through hole is arranged at the through hole.
Optionally, the inner wall of the inner cavity is provided with an anti-friction sheath.
Optionally, the friction-reducing sheath is made of reinforced polytetrafluoroethylene.
Optionally, the friction reducing sheath is made of polyether ether ketone.
Optionally, the valve core is made of metal.
Optionally, the outer surface of the valve core is provided with an anti-friction sheath.
Optionally, the sealing plug is connected to the valve seat by a thread.
The invention also provides a rotor type compressor, which comprises any one of the check valves.
The check valve provided by the invention utilizes the self-return formed by the self-weight of the valve core to achieve the same action of the spring, thereby eliminating the spring of the check valve in the prior art, ensuring that the reliability of the check valve is not limited by the spring any more and further improving the reliability of the check valve; in addition, the movement direction of the valve core and the axial direction of the air outlet channel corresponding to the air outlet are not on the same straight line, so that a flow through groove does not need to be processed on the inner side of the valve seat and the outer diameter of the valve core, and the condition that the service life of the check valve is short due to small abrasion of the edge of the flow through groove and the contact surface of the valve core is avoided; moreover, the included angle theta between the motion direction of the valve core and the horizontal plane is set to be more than 0 degree and less than or equal to 90 degrees, so that the lateral friction force between the valve core and the valve seat can be reduced, and the service life of the valve core is prolonged.
Drawings
FIG. 1 is a schematic view of a prior art check valve;
FIG. 2 is a cross-sectional view A-A of FIG. 1;
FIG. 3 is a schematic structural diagram of a check valve according to an embodiment of the present invention;
fig. 4 is a schematic structural diagram of a check valve with a friction reducing sheath according to an embodiment of the present invention.
[ reference numerals are described below ]:
1-a base;
2-a valve core;
3-a spring;
4-means for stroke limiting and coupling;
5-an air inlet;
6-air outlet;
7-a through flow groove;
21-a valve core;
22-valve seat;
23-a sealing plug;
a 24-communication channel;
25-an air inlet;
26-air outlet;
27-a second lumen;
28-a first lumen;
29-antifriction sheathing.
Detailed Description
To make the objects, advantages and features of the present invention more clear, a check valve and a rotor type compressor according to the present invention will be described in detail with reference to fig. 1 to 4. It is to be noted that the drawings are in a very simplified form and are not to precise scale, which is merely for the purpose of facilitating and distinctly claiming the embodiments of the present invention.
An embodiment of the present invention provides a check valve, which, as shown in fig. 3, includes a valve element 21 and a valve seat 22;
the valve seat 22 is provided with an inner cavity along a first direction, and the included angle theta between the first direction and the horizontal plane is more than 0 degree and less than or equal to 90 degrees; the first direction in fig. 3 forms an angle θ of 90 ° with the horizontal plane;
the valve core 21 is arranged in the inner cavity in a sliding mode and divides the inner cavity into a first inner cavity and a second inner cavity from top to bottom along the gravity direction; the lumens shown in fig. 3 may be labeled as a first lumen 28 and a second lumen 27, the first lumen 28 referring to the upper space of the lumens and the second lumen 27 referring to the lower space of the lumens;
the valve seat 22 is provided with an air inlet 25 and an air outlet 26 which are communicated with the second inner cavity 27, when the pressure of the air inlet 25 is less than or equal to the pressure of the air outlet 26, the valve core 21 is positioned in the second inner cavity 27 due to the self gravity, so that the air inlet 25 is not communicated with the air outlet 26 to prevent the refrigerant from flowing back; when the pressure of the air inlet 25 is higher than the pressure of the air outlet 26, the valve core 21 can move towards the first inner cavity 28, so that the air inlet 25 is communicated with the air outlet 26, and the refrigerant flows from the air inlet 25 to the air outlet 26.
The check valve provided by the embodiment of the invention utilizes the self-return formed by the self-weight of the valve core 21 to achieve the same action of the spring, thereby canceling the spring of the check valve in the prior art, ensuring that the reliability of the check valve is not limited by the spring any more and improving the reliability of the check valve; in addition, because the movement direction of the valve core 21 and the axial direction of the air outlet channel corresponding to the air outlet are not on the same straight line, the processing of a flow through groove is not needed on the inner side of the valve seat 22 and the outer diameter of the valve core 21, thereby avoiding the condition that the service life of the check valve is short due to small abrasion between the edge of the flow through groove and the contact surface of the valve core; moreover, the included angle theta between the motion direction of the valve core 21 and the horizontal plane is set to be more than 0 degree and less than or equal to 90 degrees, so that the gravity of the valve core 21 does not completely press the inner wall of the valve seat 22 any more, the lateral friction force between the valve core 21 and the valve seat 22 is reduced, and the service life of the valve core 21 is prolonged.
Optionally, as shown in fig. 3, the valve seat 22 further defines a communication passage 24, and the communication passage 24 is used for communicating the first inner cavity 28 with the air outlet 26. Because the air outlet 26 is communicated with the first inner cavity 28, the refrigerant can enter the first inner cavity 28 through the communication channel 24, when the pressure of the first inner cavity 28 is smaller than the pressure of the air inlet 25, the refrigerant can push the valve core 21 to move upwards, namely, to move towards the direction of the first inner cavity 28 along the extending direction of the inner cavity, at this time, the air inlet 25 is communicated with the air outlet 26, the refrigerant gas in the first inner cavity 28 can generate downward pressure when being compressed, and the pressure plays a role of air cushion buffering to prevent the valve core 21 from violently colliding with the valve seat 22; when the pressure of the first inner cavity 28 is greater than the pressure of the air inlet 25, the valve core 21 can quickly return to the original position to isolate the air inlet 25 from the air outlet 26 due to the downward pressure and the gravity of the valve core, so that the refrigerant is prevented from flowing back to the air inlet 25 from the air outlet 26.
Alternatively, as shown in fig. 3, a through hole is formed through the valve seat 22 in the direction away from the second cavity 27 in the first cavity 28, and a sealing plug 23 for sealing the through hole is disposed at the through hole. The sealing plug 23 is detachably mounted on the top of the valve seat 22, so that the valve core 21 can be replaced conveniently.
Referring to fig. 3, in the actual operation of the check valve, when the pressure generated by the refrigerant at the position of the air inlet 25 is greater than the pressure at the position of the air outlet 26, the refrigerant can jack up the valve core 21 to communicate the air inlet 25 with the air outlet 26, and the refrigerant flows out of the air outlet 26; in the process that the refrigerant flows out of the air outlet 26, a part of the refrigerant enters the first inner cavity 28 through the communication channel 24, the refrigerant in the first inner cavity 28 has downward pressure on the valve core 21, the air cushion buffering effect is achieved to prevent the valve core 21 from violently colliding with the sealing plug 23, when the pressure at the position of the air inlet 25 is equal to the pressure at the position of the air outlet 26, the valve core 21 falls back to the original position through the gravity of the valve core 21, the air inlet 25 is blocked, and the refrigerant is prevented from flowing back to the air inlet 25 from the air outlet 26; when the pressure at the position of the air inlet 25 is lower than that at the position of the air outlet 26, part of the refrigerant reaches the upper part of the valve core 21 through the communication channel 24, and the pressure at the upper part of the valve core 21 is higher than that at the lower part of the valve core 21, so that the valve core 21 quickly falls back to the original position, and the refrigerant is prevented from flowing back.
Optionally, the inner wall of the inner cavity is provided with an anti-friction sheath. As shown in fig. 4, a friction reducing jacket 29 is provided on the inner wall where the valve seat 22 meets the bore.
In the check valve provided by the embodiment of the invention, the inner wall of the inner cavity of the valve seat 22 is provided with the friction reducing sheath 29, so that the friction between the valve core 21 and the valve seat 22 can be reduced, and the service life of the valve core 21 is prolonged.
Optionally, the friction reducing sheath 29 is made of reinforced polytetrafluoroethylene or polyetheretherketone. When the material of the friction reducing sheath 29 is actually selected, a material such as Polytetrafluoroethylene (PTFE) or Polyetheretherketone (PEEK) may be selected, and the friction between the sheath made of the material and the valve element 21 is small.
Optionally, an anti-friction sheath 29 is disposed on an outer surface of the valve element 21, and the anti-friction sheath 29 may be made of a material such as reinforced polytetrafluoroethylene or polyetheretherketone, so as to reduce friction between the valve element 21 and the valve seat 22.
Alternatively, the valve body 21 is made of metal. The valve core 21 made of metal can increase the gravity of the valve core 21 and prolong the service life. In other embodiments, PTFE or PEEK may be used for the valve core 21.
Alternatively, the sealing plug 23 is connected to the valve seat 22 by means of a screw thread. The sealing plug 23 is connected with the valve seat 22 through threads, so that the sealing plug 23 can be conveniently installed and replaced. In other embodiments, the sealing plug 23 and the valve seat 22 may be connected by an interference fit.
Based on the same technical concept, the embodiment of the invention also provides a rotor type compressor, and the rotor type compressor comprises any check valve. The air inlet of the check valve can be connected with the economizer or the flash tank through a pipeline, and the air outlet of the check valve can be connected with the cylinder injection port of the compressor through a pipeline.
According to the rotor compressor provided by the embodiment of the invention, the check valve is self-restored by utilizing the self gravity of the valve core, and the same action of the spring is achieved, so that the spring of the check valve in the prior art is cancelled, the reliability of the check valve is not limited by the spring any more, and the reliability of the check valve is improved; in addition, because the movement direction of the valve core 21 and the axial direction of the air outlet channel corresponding to the air outlet 26 are not on the same straight line, the processing of a flow through groove is not needed on the inner side of the valve seat 22 and the outer diameter of the valve core 21, thereby avoiding the condition that the service life of the check valve is short due to small abrasion between the edge of the flow through groove and the contact surface of the valve core; moreover, the included angle theta between the motion direction of the valve core 21 and the horizontal plane is set to be more than 0 degree and less than or equal to 90 degrees, so that the lateral friction force between the valve core 21 and the valve seat 22 can be reduced, and the service life of the valve core 21 is prolonged.
The above description is only for the purpose of describing the preferred embodiments of the present invention, and is not intended to limit the scope of the present invention, and any variations and modifications made by those skilled in the art based on the above disclosure are within the scope of the claims of the present invention.
Claims (10)
1. A check valve, comprising a valve core and a valve seat;
the valve seat is provided with an inner cavity along a first direction, and an included angle theta between the first direction and a horizontal plane is more than 0 degree and less than or equal to 90 degrees;
the valve core is arranged in the inner cavity in a sliding mode and divides the inner cavity into a first inner cavity and a second inner cavity from top to bottom along the gravity direction;
the valve seat is provided with an air inlet and an air outlet which are communicated with the second inner cavity, and when the pressure of the air inlet is less than or equal to the pressure of the air outlet, the valve core is positioned in the second inner cavity, so that the air inlet is not communicated with the air outlet; when the pressure of the air inlet is larger than the pressure of the air outlet, the valve core moves towards the direction of the first inner cavity, so that the air inlet is communicated with the air outlet.
2. The check valve of claim 1, wherein the valve seat further defines a communication passage for communicating the first interior chamber with the gas outlet.
3. The check valve of claim 1 or 2, wherein the first cavity extends through the valve seat in a direction away from the second cavity to form a through hole, and a sealing plug for sealing the through hole is disposed at the through hole.
4. The check valve of claim 1, wherein an inner wall of the inner cavity is provided with a friction reducing sheath.
5. The check valve of claim 4, wherein the friction reducing sheath is reinforced polytetrafluoroethylene.
6. The check valve of claim 4, wherein the friction reducing sheath is of polyetheretherketone.
7. The check valve of claim 1, wherein the valve element is made of metal.
8. The check valve of claim 1 or 7, wherein an outer surface of the spool is provided with a friction reducing jacket.
9. A check valve as claimed in claim 3, wherein the sealing plug is threadedly connected to the valve seat.
10. A rotary compressor, characterized in that it comprises a non-return valve according to any one of claims 1 to 9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910122845.0A CN111577607A (en) | 2019-02-19 | 2019-02-19 | Check valve and rotor compressor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910122845.0A CN111577607A (en) | 2019-02-19 | 2019-02-19 | Check valve and rotor compressor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111577607A true CN111577607A (en) | 2020-08-25 |
Family
ID=72118720
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910122845.0A Pending CN111577607A (en) | 2019-02-19 | 2019-02-19 | Check valve and rotor compressor |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111577607A (en) |
Citations (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH036171U (en) * | 1989-06-08 | 1991-01-22 | ||
| JPH094580A (en) * | 1995-06-16 | 1997-01-07 | Dia Shinku Kk | Screw vacuum pump |
| CN2589696Y (en) * | 2002-12-25 | 2003-12-03 | 瑞智精密股份有限公司 | Improved arrangement for compressor back valve |
| CN1512066A (en) * | 2002-12-30 | 2004-07-14 | 大金工业株式会社 | Turbine compressor |
| US20040136851A1 (en) * | 2003-01-15 | 2004-07-15 | Rechi Precision Co., Ltd. | Compressor check valve |
| CN2806920Y (en) * | 2005-07-22 | 2006-08-16 | 银川福顺科贸有限公司 | One-way valve for pressure stabilization of water meter |
| CN201162675Y (en) * | 2007-09-28 | 2008-12-10 | 珠海格力电器股份有限公司 | Rotary compressor with injection enthalpy-increasing function |
| CN201610944U (en) * | 2010-03-30 | 2010-10-20 | 铁岭方众阀门有限公司 | Elevating type micro-damp slow closed check valve |
| CN202545902U (en) * | 2012-05-14 | 2012-11-21 | 生贵阀门有限公司 | Spherical sealing high-pressure check valve |
| CN203516853U (en) * | 2013-08-29 | 2014-04-02 | 福建新达阀门有限公司 | Ceramic core check valve |
| CN104214375A (en) * | 2014-09-02 | 2014-12-17 | 宣达实业集团有限公司 | HVDC (High Voltage Direct Current) swing check valve |
| CN206145154U (en) * | 2016-11-08 | 2017-05-03 | 倪岩土 | Marine external screw thread high pressure check valve |
| CN206988496U (en) * | 2017-08-02 | 2018-02-09 | 上海格兰克林（集团）有限公司 | A kind of air compressor minimum pressure valve |
| KR20180094408A (en) * | 2017-02-15 | 2018-08-23 | 엘지전자 주식회사 | High pressure compressor and refrigerating machine having the same |
-
2019
- 2019-02-19 CN CN201910122845.0A patent/CN111577607A/en active Pending
Patent Citations (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH036171U (en) * | 1989-06-08 | 1991-01-22 | ||
| JPH094580A (en) * | 1995-06-16 | 1997-01-07 | Dia Shinku Kk | Screw vacuum pump |
| CN2589696Y (en) * | 2002-12-25 | 2003-12-03 | 瑞智精密股份有限公司 | Improved arrangement for compressor back valve |
| CN1512066A (en) * | 2002-12-30 | 2004-07-14 | 大金工业株式会社 | Turbine compressor |
| US20040136851A1 (en) * | 2003-01-15 | 2004-07-15 | Rechi Precision Co., Ltd. | Compressor check valve |
| CN2806920Y (en) * | 2005-07-22 | 2006-08-16 | 银川福顺科贸有限公司 | One-way valve for pressure stabilization of water meter |
| CN201162675Y (en) * | 2007-09-28 | 2008-12-10 | 珠海格力电器股份有限公司 | Rotary compressor with injection enthalpy-increasing function |
| CN201610944U (en) * | 2010-03-30 | 2010-10-20 | 铁岭方众阀门有限公司 | Elevating type micro-damp slow closed check valve |
| CN202545902U (en) * | 2012-05-14 | 2012-11-21 | 生贵阀门有限公司 | Spherical sealing high-pressure check valve |
| CN203516853U (en) * | 2013-08-29 | 2014-04-02 | 福建新达阀门有限公司 | Ceramic core check valve |
| CN104214375A (en) * | 2014-09-02 | 2014-12-17 | 宣达实业集团有限公司 | HVDC (High Voltage Direct Current) swing check valve |
| CN206145154U (en) * | 2016-11-08 | 2017-05-03 | 倪岩土 | Marine external screw thread high pressure check valve |
| KR20180094408A (en) * | 2017-02-15 | 2018-08-23 | 엘지전자 주식회사 | High pressure compressor and refrigerating machine having the same |
| CN206988496U (en) * | 2017-08-02 | 2018-02-09 | 上海格兰克林（集团）有限公司 | A kind of air compressor minimum pressure valve |
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| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
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| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20200825 |