R744 heat pump air conditioner low permeability, high temperature resistant filling valve

Abstract

The application discloses a low-permeability and high-temperature-resistant charging valve for R744 heat pump air conditioner, which comprises a charging valve core and a charging valve body, wherein the charging valve core comprises a center rod, a compression spring, a fastening block, a sealing body and a sealing gasket; the upper and lower ends of the center rod are provided with outward protruding stoppers for respectively blocking the compression spring and the sealing gasket; the compression spring is located between the top stopper of the center rod and the fastening block; the outer side surface of the fastening block is provided with threads matched with the inner cavity of the charging valve body; the top of the fastening block is in the form of a crossbeam structure; the two sides of the crossbeam are provided with through holes communicated with the inner center cavity of the fastening block; the sealing body is provided with a center through hole, the upper end of which is located in the center cavity of the fastening block; the top surface of the sealing gasket is in close contact with the bottom surface of the sealing body to form a sealing surface; and the bottom surface of the sealing gasket is in close contact with the bottom stopper of the center rod to form a sealing surface. Compared with the conventional refrigerant or the existing R744 refrigerant charging valve, the charging valve has the good performances of high-temperature resistance and low permeability.

Description

Technical Field

[0001] This invention relates to the technical field of R744 heat pump air conditioning systems, specifically a low-permeability, high-temperature resistant charging valve for R744 heat pump air conditioning. Background Technology

[0002] According to relevant agreements, the use of traditional HFC refrigerants such as R134a will be gradually restricted. CO2, as a new type of refrigerant, has advantages such as being non-toxic, stable, and biodegradable, making it an environmentally friendly and natural refrigerant, and it is beginning to be gradually applied in the automotive air conditioning heat pump field. Meanwhile, with the development of new energy vehicles, pure electric vehicles are becoming increasingly widely accepted. Since pure electric vehicles do not have an engine to provide a heat source, they need to use PTC or heat pump air conditioning for heating. In winter, using PTC heating leads to a significant increase in the power consumption of the air conditioning system, resulting in a significant decrease in the driving range of electric vehicles, with a winter range reduction of up to 30-50%. Currently, conventional heat pump systems using R134a refrigerant have low operating efficiency in low-temperature environments. CO2, as a refrigerant, has superior heat pump performance and can significantly increase the driving range in low-temperature environments. Compared with R134a air conditioning systems, R744 heat pump air conditioning has extremely high requirements for the leakage rate of all system components. The charging valves used in traditional R134a and other refrigerant systems cannot meet the requirements for R744 systems.

[0003] R744 heat pump air conditioning system charging valves are now in mass production. Their structure is basically the same as that of traditional refrigerant charging valves, using rubber sealing rings to seal the valve body and valve core. However, due to the high operating pressure of R744 heat pump air conditioning systems and the small molecular weight of CO2, it has extremely strong permeability to rubber materials under high pressure. Therefore, the R744 charging valve, which uses rubber sealing rings for sealing, has a relatively high leakage rate, affecting the leakage rate of the entire system. Summary of the Invention

[0004] The purpose of this invention is to provide a low-permeability, high-temperature resistant charging valve for R744 heat pump air conditioners, so as to overcome the shortcomings of the existing technology.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is: a low-permeability, high-temperature resistant charging valve for R744 heat pump air conditioners, comprising a charging valve core and a charging valve body. The charging valve core includes a central rod, a compression spring, a fastening block, a sealing body, and a sealing gasket. The central rod is sequentially equipped with the compression spring, fastening block, sealing body, and sealing gasket. Outwardly protruding blocks are provided at the upper and lower ends of the central rod to respectively block the compression spring and the sealing gasket, thereby ensuring that the central rod, compression spring, fastening block, sealing body, and sealing gasket... The five parts form a unified whole; the compression spring is located between the top stop block of the center rod and the fastening block; the outer surface of the fastening block is provided with threads that match the inner cavity of the filling valve body; the top of the fastening block is a crossbeam structure; the two sides of the crossbeam are provided with through holes that communicate with the central cavity inside the fastening block; the sealing body is provided with a central through hole, the upper end of which is located in the central cavity of the fastening block; the top surface of the sealing gasket fits against the bottom surface of the sealing body to form a sealing surface; the bottom surface of the sealing gasket fits against the bottom stop block of the center rod to form a sealing surface.

[0006] Furthermore, the crossbeam of the fastening block is provided with a central hole through which the central rod passes. The inner diameter of the central hole is the same as the diameter of the central rod or slightly larger than the diameter of the central rod, and the inner wall of the central hole is in sliding contact with the outer wall of the central rod.

[0007] Furthermore, the bottom of the fastening block is provided with an inwardly curled edge structure for restricting and positioning the sealing body.

[0008] Furthermore, the outer wall of the sealing body is provided with a gap groove that matches the bottom rolled edge of the fastening block.

[0009] Furthermore, the sealing gasket is a metal disc-shaped gasket with a stainless steel base and a non-metallic coating on its surface.

[0010] Furthermore, the sealing gasket has three sealing surfaces: a top upper sealing surface, a top lower sealing surface, and a bottom lower sealing surface. The top upper sealing surface fits into the bottom surface of the sealing body, the top lower sealing surface fits into the internal stepped surface of the filling valve body, and the bottom lower sealing surface fits into the bottom stop of the center rod.

[0011] Furthermore, the bottom stop of the central rod is provided with a variable diameter section, the diameter of which increases from top to bottom, and the diameter of its lower end is consistent with the diameter of the through hole of the sealing gasket.

[0012] Furthermore, the filling valve body is a multi-section cylindrical hollow structure, in which a threaded structure matching the fastening block of the valve core and a sealing stepped surface structure cooperating with the sealing gasket of the valve core are provided inside the hollow.

[0013] The beneficial effects of this invention are as follows: This invention uses a single metal disc-shaped gasket, in conjunction with a central rod, a sealing body, and a charging valve body, to simultaneously satisfy the sealing between the valve core and the valve body, and between the moving central rod inside the valve core and the sealing body; the sealing between the valve core and the valve body is achieved by tightening the crossbeam on the solid, causing the sealing body to compress the sealing gasket, which then engages with the sealing surface on the valve body to form a sealing structure; the sealing inside the valve core is achieved by the compression of a spring, with the top of the central rod subjected to spring tension, causing the bottom of the central rod to compress the sealing gasket, and the gasket deforms to form a sealing structure; this invention has a simple structure, using a single sealing gasket to seal two sealing structures; at the same time, the main body of the sealing gasket is a metal structure with a thin non-metallic coating on the surface, resulting in extremely low overall permeability of the charging valve, avoiding the high CO2 permeability caused by using rubber sealing rings; furthermore, the main body of the sealing gasket is made of metal, with a thin non-metallic coating on its surface, which has high-temperature resistant properties, making the charging valve of this invention, compared with the charging valves used for traditional refrigerants or existing R744 refrigerants that use rubber sealing rings, both have excellent performance in terms of high temperature resistance and low permeability.

[0014] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the filling valve core structure of the present invention;

[0016] Figure 2 This is a cross-sectional view of the filling valve core of the present invention;

[0017] Figure 3 This is a schematic diagram of the structure of the valve core and valve body after assembly according to the present invention;

[0018] Figure 4 This is a schematic diagram of the structure of the central rod of the valve core component of the present invention;

[0019] Figure 5 This is a schematic diagram of the structure of the valve core component fastening block of the present invention;

[0020] Figure 6 This is a schematic diagram of the structure of the valve core component sealing body of the present invention;

[0021] Figure 7 This is a schematic diagram of the structure of the sealing gasket for the valve core component of the present invention;

[0022] The markings in the diagram are as follows: 1-Center rod, 1a-Bottom surface of upper stop block, 1b-Cylindrical section, 1c-Reducing diameter section, 1d-Top surface of lower stop block, 2-Compression spring, 3-Fastening block, 3a-Crossbeam, 3b-Center hole, 3c-External thread, 3d-Curled edge, 3e-Through hole, 4-Sealing body, 4a-Center through hole, 4b-Main body of sealing body, 4c-Gap groove, 4d-Bottom surface of sealing body, 5-Sealing gasket, 5a-Top surface of large surface, 5b-Bottom surface of large surface, 5c-Bottom surface of small surface, 6-Filling valve body. Detailed Implementation

[0023] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0024] like Figures 1 to 3 As shown, the R744 heat pump air conditioner low permeability, high temperature resistant charging valve of the present invention includes a charging valve core and a charging valve body. The following is a detailed description of each part:

[0025] like Figure 1 As shown, the filling valve core includes a central rod 1, a compression spring 2, a fastening block 3, a sealing body 4, and a sealing gasket 5. The central rod 1 runs through the entire valve core, and the compression spring 2, fastening block 3, sealing body 4, and sealing gasket 5 are sequentially assembled on the rod. Outwardly protruding blocks are provided at the upper and lower ends of the central rod 1 to block the compression spring 2 and sealing gasket 5 respectively, so that the five parts—central rod 1, compression spring 2, fastening block 3, sealing body 4, and sealing gasket 5—form a unified whole. The valve core manufacturing process is as follows: the bottom of the central rod 1 is stamped; the sealing gasket 5, sealing body 4, fastening block 3, and compression spring 2 are sequentially assembled; and then the top of the central rod is formed by extrusion molding, at which point the spring is in a compressed state.

[0026] like Figure 4 As shown, the middle part of the central rod 1 is a cylindrical segment 1b, with integrally formed stops at its top and bottom. The bottom surface 1a of the upper stop and the top surface 1d of the lower stop are perpendicular to the middle part, as shown. Figure 1 The bottom surface 1a of the upper stop block contacts the spring, causing the spring to be in a compressed state. A variable diameter section 1c is also provided on the bottom stop block of the center rod. The diameter of this variable diameter section 1c increases sequentially from top to bottom, and its lower end diameter matches the through-hole diameter of the sealing gasket 5. The preferred material for the center rod 1 is carbon steel or stainless steel; preferably, its surface has an anti-rust coating.

[0027] like Figure 5 and Figure 3As shown, the fastening block 3 is a cylindrical hollow structure, with a clearance fit between the top central hole 3b and the middle cylindrical section 1b of the central rod 1; the fastening block has an external thread 3c on its side, which matches the internal thread 6a of the valve body, connecting the valve core and the valve body through the thread structure; the top of the fastening block 3 is a crossbeam structure, with through holes 3e on both sides of the crossbeam 3a that communicate with the central cavity of the fastening block, allowing refrigerant such as CO2 to enter the valve body through these through holes during the charging process; the bottom of the fastening block 3 has an inwardly curled edge 3d structure for fixing the sealing body 4; the sealing body 4 and the fastening block 3 are connected by an extrusion molding process, causing the bottom curled edge 3d of the fastening block 3 to curl inward and deform, fitting with the clearance groove 4c in the middle of the sealing body 4, allowing the fastening block 3 and the sealing body 4 to move relative to each other without separating, forming a connected body; the preferred material for the fastening block 3 is brass.

[0028] like Figure 6 and Figure 7 As shown, the sealing body 4 has a dumbbell-shaped structure with a central through hole 4a, which is clearance-fitted with the cylindrical section 1b of the central rod 1; the sealing gasket 5 is a metal disc-shaped gasket, the base of which is made of stainless steel, preferably 301 stainless steel; the surface is coated with a non-metallic coating, preferably one or more layers of FKM / PTFE / NBR / HNBR; the gasket is a flat plate formed by stamping to form a disc-shaped structure. The large surface 5a of the sealing gasket 5 serves as the top sealing surface and fits with the bottom surface 4d of the sealing body, and the small surface 5c of the sealing gasket 5 serves as the bottom sealing surface and fits with the top surface 1d of the lower stop block of the central rod. Under the action of the compression spring 2, they are tightly fitted together, forming a seal for the fluid channel during the filling process. At the same time, the pressure inside the cavity after filling squeezes the bottom surface of the central rod 1, further squeezing the sealing gasket 5, thereby further improving the pressure-bearing performance between the central rod 1 and the sealing body 4 and the sealing gasket 5. Meanwhile, as... Figure 3 As shown, after the fastening block 3 is tightened to the valve body 6 via a threaded connection, the sealing gasket 5 is compressed by the sealing body 4, so that the large bottom surface 5b of the sealing gasket 5 matches the stepped surface 6b inside the valve body 6 to form a seal.

[0029] Preferably, the sealing body 4 is made of stainless steel, carbon steel or brass, and preferably, the surface is plated with an anti-rust and anti-corrosion layer.

[0030] Preferably, the valve body 6 is made of aluminum alloy or stainless steel; the valve body is connected to other components of the heat pump system by welding or other connection methods.

[0031] During the charging process, the external component presses down on the central rod 1, creating a gap channel between the central rod 1 and the sealing gasket 5. The refrigerant passes through the through hole of the fastening block and the central through hole of the sealing body in sequence, and then enters the heat pump system through the gap channel formed between the central rod 1 and the sealing gasket 5. After the charging is completed, the central rod 1 returns to its initial state by the action of the compression spring 2, compressing the sealing gasket 5 and forming a sealed state.

[0032] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the above embodiments do not limit the scope of protection of the present invention in any way, and all technical solutions obtained by equivalent substitution or other means fall within the scope of protection of the present invention. Parts not covered in this invention are the same as or can be implemented using existing technology.

Claims

1. A low-permeability, high-temperature resistant charging valve for R744 heat pump air conditioners, comprising a charging valve core and a charging valve body, characterized in that, The filling valve body is a multi-section cylindrical hollow structure, with a threaded structure and a sealing stepped surface structure inside. The filling valve core includes a central rod, a compression spring, a fastening block, a sealing body, and a sealing gasket. The central rod is sequentially equipped with the compression spring, fastening block, sealing body, and sealing gasket. The upper and lower ends of the central rod have outwardly protruding stops to block the compression spring and sealing gasket respectively, forming a unified whole. The compression spring is located between the top stop and the fastening block on the central rod. The outer surface of the fastening block has... The fastening block has threads that match the threaded structure of the filling valve body. The top of the fastening block is a crossbeam structure, and the two sides of the crossbeam have through holes that communicate with the central cavity inside the fastening block. The sealing body has a central through hole, and its upper end is located in the central cavity of the fastening block. The sealing gasket has three sealing surfaces: a top upper sealing surface, a top lower sealing surface, and a bottom lower sealing surface. The top upper sealing surface fits into the bottom surface of the sealing body to form a sealing surface. The top lower sealing surface fits into the sealing step surface structure of the filling valve body to form a sealing surface. The bottom lower sealing surface fits into the bottom stop of the central rod to form a sealing surface.

2. The low-permeability, high-temperature resistant charging valve for R744 heat pump air conditioners according to claim 1, characterized in that, The crossbeam of the fastening block is provided with a central hole through which the central rod passes. The inner diameter of the central hole is the same as the diameter of the central rod, and the inner wall of the central hole is in sliding contact with the outer wall of the central rod.

3. The low-permeability, high-temperature resistant charging valve for R744 heat pump air conditioners according to claim 1, characterized in that, The bottom of the fastening block has an inwardly curled edge structure for limiting and positioning the sealing body.

4. The low-permeability, high-temperature resistant charging valve for R744 heat pump air conditioners according to claim 3, characterized in that, The outer wall of the sealing body is provided with a gap groove that matches the bottom rolled edge of the fastening block.

5. A low-permeability, high-temperature resistant charging valve for R744 heat pump air conditioning according to claim 1, characterized in that, The sealing gasket is a metal disc-shaped gasket with a stainless steel base and a non-metallic coating on its surface.

6. The low-permeability, high-temperature resistant charging valve for R744 heat pump air conditioners according to claim 1, characterized in that, The bottom stop of the central rod is provided with a variable diameter section, the diameter of which increases from top to bottom, and the diameter of its lower end is consistent with the diameter of the through hole of the sealing gasket.

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