Large-diameter electronic expansion valve with precise flow regulation

Abstract

The utility model relates to the technical field of expansion valve, especially large -diameter electronic expansion valve of accurate flow regulation, its because spring guide rail and slip ring mutually cooperate, so slip ring is the axial movement of sliding bearing spiral movement, the upper end surface of slip ring and spring guide rail contact when, valve needle subassembly is in the most lower end at this moment, valve is all closed, and no medium passes in the valve, slip ring lower end slip ring and spring guide rail lower end contact when, valve needle subassembly is in the most upper end at this moment, and the valve port opening is biggest, and the flow of medium passing in the valve is biggest, by the magnetic separation pipe subassembly, magnetic rotor subassembly, valve seat spare, valve needle subassembly, valve base, outer leakage O type sealing ring and inner leakage O type sealing ring are composed, its characterized in that, the magnetic separation pipe subassembly is composed of magnetic separation ring and sliding bearing assembly, and the upper portion 122a of spring guide rail is fixed in the groove of sliding bearing and is clamped, and slip ring moves along sliding bearing axial movement, and the movement of slip ring is rotated control by magnetic rotor subassembly.

Description

Technical Field

[0001] This utility model relates to the technical field of expansion valves, and in particular to a large-diameter electronic expansion valve for precise flow regulation. Background Technology

[0002] The heat exchange efficiency of a refrigerant system primarily depends on the refrigerant pressure at the high-pressure end and the condenser outlet temperature. Refrigerant flow control is typically determined based on the outlet temperature and pressure of the cooling unit, making flow control quite complex. Generally, an electronic expansion valve is used to throttle and reduce the pressure of the refrigerant from the condenser outlet. The flow rate of refrigerant supplied from the condenser to the evaporator is adjusted based on the outlet temperature of the evaporator or other temperatures requiring regulation, thus providing different refrigerant flows under varying loads. In today's rapidly developing new energy environment, the requirements for electronic expansion valves at the entire heat pump end are becoming increasingly stringent. Electronic expansion valves not only require precise flow control under high pressure but also strong integration capabilities. Currently, large-diameter electronic expansion valves generally have low flow control accuracy and significant leakage after valve closure.

[0003] Therefore, to address these technical issues, an electronic expansion valve core is provided that offers precise flow regulation, simple structure, high driving torque, and low leakage. Utility Model Content

[0004] To solve the above-mentioned technical problems, this utility model provides a large-diameter electronic expansion valve for precise flow regulation.

[0005] This utility model discloses a large-diameter electronic expansion valve for precise flow regulation, comprising a magnetic shielding tube assembly, a magnetic rotor assembly, a valve seat component, a valve needle assembly, a valve base, an external leakage O-ring seal, and an internal leakage O-ring seal. The magnetic shielding tube assembly is characterized by comprising a magnetic shielding ring and a sliding bearing assembly. The sliding bearing assembly comprises a sliding bearing, a spring guide rail, and a slip ring. The sliding bearing and the magnetic shielding ring are interference-fitted, and the sliding bearing is pressed into the inner cavity of the magnetic shielding ring. The top flat end of the sliding bearing contacts and limits contact with the top flat surface 11a of the magnetic shielding ring. A clearance structure is designed at the top arc position 11b of the top of the magnetic shielding ring, and a small groove is opened at the lower end of the sliding bearing for positioning during assembly. The upper end of the sliding bearing has four feature grooves, which are the limiting feature grooves after being riveted to the magnetic isolation ring. A is the riveting point. The spring guide rail and the slip ring are sleeved on the shaft tube of the sliding bearing. The upper part 122a of the spring guide rail is fixed in the groove of the sliding bearing. The slip ring moves along the axial direction of the sliding bearing. The movement of the slip ring is controlled by the rotation of the magnetic rotor assembly. Because the spring guide rail and the slip ring cooperate with each other, the axial movement of the slip ring in the sliding bearing is a helical motion. When the upper end face of the slip ring contacts the spring guide rail, the valve needle assembly is at the lowest point, the valve is fully closed, and no medium passes through the valve. When the lower end of the slip ring contacts the lower end of the spring guide rail, the valve needle assembly is at the highest point, the valve opening is at its maximum, and the flow rate of the medium passing through the valve is at its maximum.

[0006] Preferably, the magnetic rotor assembly consists of a magnetic rotor support frame and a brake rod, with the brake rod employing a three-jaw structure design; the screw and brake rod are laser-welded at point B after press-fitting; the screw and magnetic ring employ a three-jaw structure design to prevent the magnetic rotor assembly from swaying due to unilateral force during rotation; the screw and brake rod are laser-welded at point B after press-fitting to ensure their bonding strength; and the magnetic rings are magnetized and tested.

[0007] Preferably, the valve seat component consists of a roller bearing and a valve seat. The roller bearing is installed in the bearing chamber of the valve seat, and the screw on the roller bearing is interference-fitted with the inner ring of the roller bearing. A raised chamfer is provided at the valve seat 32b. The valve seat is designed internally, and the valve needle assembly 4 is guided by the valve seat cavity. The roller bearing reduces the friction in the power transmission of the screw and improves the transmission efficiency of the screw. The 23 on the magnetic rotor assembly is interference-fitted with the inner ring of the roller bearing. This fit can better ensure the coaxiality of the magnetic rotor assembly during rotation and also improve the transmission efficiency. The valve seat is designed internally, which is beneficial for the installation of the valve needle assembly and can also restrict the valve needle assembly to only axial movement and not axial rotation. The valve needle assembly is guided by the valve seat cavity to ensure the coaxiality of the valve needle during movement.

[0008] Preferably, the valve needle assembly consists of a stop ring, an inner valve core, a valve needle spring, and a valve needle. The valve needle has four balance holes, and the upper part of the valve needle is designed with two-end stop structures that cooperate with the valve seat inside the valve seat assembly. The upper part of the valve needle has a groove that cooperates with the inner valve core. The inner valve core and the valve needle are sealed by a 42c structure, and the bottom of the inner valve core thread is designed with a 42b. The stop ring cooperates with the inner valve core in a contour design, and the valve needle spring acts as a buffer. The four balance holes of the valve needle can quickly balance the pressure and improve the speed of valve action. The two-end stop structures on the upper part of the valve needle, through cooperation with the valve seat inside the valve seat assembly, ensure that the valve needle can only move axially during operation and cannot move radially. By controlling the clearance between the two parts, the valve can prevent the valve from skipping steps. The groove on the upper part of the valve needle cooperates with the inner valve core, preventing the inner valve core from rotating inside the valve needle. The groove is deepened, which is beneficial for balancing internal and external pressure and removing wear impurities. The valve core and valve needle are sealed by a 42c structure. When the valve needle spring is compressed during the motor drive, the inner valve core and valve needle contact to form a seal. The motor drives the rotor, and the thread drives the valve needle spring to move, which can realize precise control of the refrigerant flow. After the inner valve core has moved a certain distance, it drives the valve needle to move, achieving a large-diameter effect and enabling a larger flow of refrigerant. The bottom of the inner valve core thread is designed with a 42b, which not only balances the pressure but also carries away impurities at the thread, preventing the valve from jamming and failing due to the accumulation of impurities. The stop ring is made of stainless steel and has a contour design to match the inner valve core, reducing wear. The valve needle spring acts as a buffer to prevent the inner valve core from suddenly stopping when it encounters the lower stroke limit during valve closing, which would generate a large inertial force and cause excessive axial force in the component structure, resulting in the inability to open the valve. At the same time, the spring force ensures the seal between the inner valve core and the valve needle and also reduces the opening force required when opening the valve.

[0009] Preferably, the inner valve core material is SUS304; the inner valve core material of SUS304 has strong wear resistance and can effectively increase the valve life.

[0010] Preferably, the screw thread is machined using a thread rolling process; compared with ordinary machined threads, the screw thread has a better surface roughness, and the thread surface strength and hardness are higher, which greatly improves the wear resistance of the thread and increases the overall life of the valve.

[0011] Preferably, the sliding bearing has a through-hole design to prevent the tail of the screw on the magnetic rotor assembly from contacting the sliding bearing and causing the valve to malfunction, while also ensuring the coaxiality of the magnetic rotor assembly during rotation.

[0012] Preferably, the magnetic shielding ring is made of deep-drawn SUS304 stainless steel; the use of SUS304 stainless steel in the magnetic shielding ring improves its service life.

[0013] Compared with the prior art, the beneficial effects of this utility model are as follows: because the spring guide rail and the slip ring cooperate with each other, the axial movement of the slip ring in the sliding bearing is a helical motion. When the upper end face of the slip ring contacts the spring guide rail, the valve needle assembly is at the lowest point, the valve is fully closed, and no medium passes through the valve. When the lower end of the slip ring contacts the lower end of the spring guide rail, the valve needle assembly is at the highest point, the valve opening is at its maximum, and the flow rate of the medium passing through the valve is at its maximum. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the isometric structure of this utility model; Figure 2 This is an exploded structural diagram of the present invention; Figure 3 This is a schematic diagram of the first structure of the magnetic shielding tube assembly; Figure 4 This is an enlarged schematic diagram of the spring guide rail and slip ring structure of this utility model; Figure 5 This is a first cross-sectional view of the magnetic rotor assembly of this utility model; Figure 6 This is a first sectional view of the valve seat component of this utility model; Figure 7 This is a cross-sectional structural diagram of the valve needle assembly and valve base, etc. Figure 8 This is the first sectional view of the valve needle assembly; Figure 9 This is the second sectional view of the valve needle assembly; Figure 10 This is a diagram showing the distribution of key points in the valve core; Figure 11 This is a schematic diagram of the second structure of the magnetic shielding tube assembly; Figure 12 This is a schematic diagram of the third structure of the magnetic shielding tube assembly; Figure 13 This is a second sectional view of the valve seat component of this utility model.

[0015] The following are labels in the attached diagram: 1. Magnetic shielding tube assembly; 2. Magnetic rotor assembly; 3. Valve seat component; 4. Valve needle assembly; 5. Valve base; 6. External leakage O-ring seal; 7. Internal leakage O-ring seal; 11. Magnetic shielding tube; 12. Sliding bearing assembly; 121. Sliding bearing; 122. Spring guide rail; 123. Slip ring; 121a. Top flat end; 121b. Top end; 121c. Small groove; 121d. Feature groove; 121e. Groove; 21. Magnetic rotor support frame; 22. Magnetic ring; 23. Screw; 24. Brake lever; 31. Roller bearing; 32. Valve seat; 32c. Guide groove; 41. Stop ring; 42. Inner valve core; 43. Valve needle spring; 44. Valve needle; 44c. Balance hole; 44a. End-stop structure; 44b. Groove. Detailed Implementation

[0016] To facilitate understanding of this utility model, a more complete description will be given below with reference to the accompanying drawings. This utility model can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to make the disclosure of this utility model more thorough and complete.

[0017] Example 1 like Figures 1 to 13 As shown, this utility model discloses a large-diameter electronic expansion valve for precise flow regulation, comprising a magnetic shielding tube assembly 1, a magnetic rotor assembly 2, a valve seat component 3, a valve needle assembly 4, a valve base 5, an external leakage O-ring seal 6, and an internal leakage O-ring seal 7. The magnetic shielding tube assembly 1 consists of a magnetic shielding tube 11 and a sliding bearing assembly 12. The sliding bearing assembly 12 consists of a sliding bearing 121, a spring guide rail 122, and a slip ring 123. The sliding bearing 121 and the magnetic shielding tube 11 are press-fitted into the inner cavity of the magnetic shielding tube 11. The top plane 121a of the sliding bearing contacts and limits the movement of the top plane 11a of the magnetic shielding tube 11. The top 121b is designed with a clearance structure at the top arc position 11b of the magnetic shielding tube 11. The lower end of the sliding bearing 121 has a small groove 121c for positioning during assembly. The upper end of the sliding bearing 121 has four feature grooves 121d, which are the limiting feature grooves after being riveted to the magnetic shielding tube 11. A is the riveting point. The spring guide rail 122 and the slip ring 123 are sleeved on the shaft tube of the sliding bearing 121. The upper part 122a of the spring guide rail is fixed in the groove 121e of the sliding bearing 121. The slip ring 123 can move along the axial direction of the sliding bearing 121. The movement of the slip ring 123 is controlled by the rotation of the magnetic rotor assembly 2 driving the stop rod 24. The magnetic rotor assembly 2 consists of a magnetic rotor support frame 21, a magnetic ring 22, a screw 23, and a stop rod 24. The stop rod 24 adopts a three-jaw structure design. The screw 23 and the stop rod 24 are laser welded after being press-fitted. The screw 23 and the magnetic ring 22 are connected by injection molding. The magnetic ring 22 is made of neodymium iron boron and is processed by bonding process. The valve seat component 3 consists of a ball bearing 31 and a valve seat 32. The ball bearing 31 is installed in the bearing chamber 32a of the valve seat 32. The screw 23 on the magnetic rotor assembly 2 is interference-fitted with the inner ring of the ball bearing 31. The valve seat 32b is provided with a raised chamfer. The valve seat 32 is designed with a guide groove 32c inside. The valve needle assembly 4 is guided by the valve seat cavity 32d.

[0018] In this embodiment, because the spring guide rail 122 and the slip ring 123 cooperate with each other, the axial movement of the slip ring 123 in the sliding bearing 121 is a helical motion. When the upper end face 123a of the slip ring 123 contacts the spring guide rail 122, the valve needle is at the lowest point, the valve is fully closed (opening degree is 0%), and no medium passes through the valve. When the lower end 123a of the slip ring 123 contacts the lower end 122b of the spring guide rail 122, the valve needle is at the highest point, the valve opening degree is the largest (100%), and the flow rate of the medium passing through the valve is the largest. The stop rod 24 adopts a three-jaw structure design to prevent the magnetic rotor assembly 2 from being swayed by a unilateral force during rotation. After the screw 23 and the stop rod 24 are press-fitted, laser welding is performed at point B to ensure their bonding strength. The magnetic ring 22 is made of neodymium iron boron and is processed by bonding process. The screw 23 and the magnetic ring 22 are connected by injection molding. After injection molding, O2 is magnetized and tested. The screw 23 on the magnetic rotor assembly 2 has an interference fit with the inner ring of the ball bearing 31. This fit better ensures the coaxiality of the magnetic rotor assembly 2 during rotation and also improves the transmission efficiency. The raised chamfer at the valve seat 32b is used for riveting to fix the ball bearing 31 axially, so that it will not detach from the valve seat 32. The guide groove 32c inside the valve seat is designed to facilitate the installation of the valve needle assembly 4 and also to restrict the valve needle assembly 4 to only axial movement and prevent axial rotation. The valve needle assembly 4 is guided to the inner cavity 32d of the valve seat to ensure the coaxiality of the valve needle during movement.

[0019] Example 2 like Figures 1 to 13 As shown, based on Embodiment 1, this utility model provides a large-diameter electronic expansion valve for precise flow regulation. The valve needle assembly 4 consists of a stop ring 41, an inner valve core 42, a valve needle spring 43, and a valve needle 44. The valve needle 44 has four balance holes 44c. The upper part of the valve needle 44 is designed with two-end stop structures 44a, which cooperate with the valve seat 32c inside the valve seat assembly 3. The upper part of the valve needle 44 has a groove 44b that cooperates with the inner valve core 42. The inner valve core 42 and the valve needle 44 are sealed by the 42c structure. The bottom of the thread of the inner valve core 42 is designed with a 42b. The stop ring 41 cooperates with the inner valve core 42 to form a contour design. The valve needle spring 43 plays a buffering role.

[0020] In this embodiment, the valve needle 44 has four balance holes 44c, which can quickly balance the pressure and improve the speed of valve action. The upper part of the valve needle 44 is designed with two end stop structures 44a, which cooperate with the valve seat 32c inside the valve seat component 3, so that the valve needle 44 can only move axially during operation and cannot move radially. By controlling the fit clearance between the two parts, the valve can prevent the valve from missing steps. The upper part of the valve needle 44 has a groove 44b that cooperates with the inner valve core 42, so that the inner valve core 42 will not rotate inside the valve needle. The groove is deepened, which is conducive to balancing internal and external pressure and removing wear impurities. The inner valve core 42 and the valve needle 44 are sealed by the 42c structure. When the valve needle spring 43 is compressed during the motor driving force, the inner valve core 42 and the valve needle 44 come into contact to form a seal. The motor drives the rotor, and the thread drives the valve needle. The spring 43 operates to precisely control the refrigerant flow. After the inner valve core 42 has moved a certain distance, it drives the valve needle 44 to achieve a large-diameter effect and allow for a larger flow of refrigerant. The inner valve core 42 has a 42b at the bottom of its thread, which balances the pressure and removes impurities from the thread, preventing the valve from jamming due to the accumulation of impurities. The stop ring 41 is made of stainless steel and has a contour design to match the inner valve core 42, reducing wear. The valve needle spring 43 acts as a buffer to prevent the inner valve core 42 from suddenly stopping when it encounters the lower stroke limit during valve closing, which would generate a large inertial force and cause excessive axial force in the component structure, resulting in the inability to open the valve. At the same time, the spring force ensures the seal between the inner valve core 42 and the valve needle 44 and also reduces the opening force required when opening the valve.

[0021] like Figures 1 to 13As shown, this utility model discloses a large-diameter electronic expansion valve for precise flow regulation. During operation and assembly, the valve seat component 3 is assembled first, and then the magnetic rotor assembly 2 is placed inside the valve seat component 3. The lead screw 23 and the ball bearing 31 are interference-fitted, and the inner ring of the ball bearing 31 contacts the shoulder of the lead screw 23. After the valve needle assembly 5 is assembled, circumferential welding is performed, with the welding point at point B. Then, the valve needle assembly 4 is fitted to the valve seat assembly 3 through the guide hole. The valve needle assembly 4 and the magnetic rotor assembly 2 are connected by threads. The valve base 5 and the valve seat 32 are press-fitted, and the limiting surface for the axial press-fitting of the valve base is the plane 32e inside the valve seat 32. Then, circumferential welding is performed at point C. The sliding bearing assembly 12 is pressed into the magnetic shielding tube 11, ensuring coaxiality after pressing. Then, spot riveting is performed, and the magnetic shielding tube assembly 1 and the valve seat assembly 3 are tightly connected. The connection point needs to be cleaned. The magnetic shielding tube assembly 1 and the valve seat assembly 3 are circumferentially welded together at point D. An external O-ring seal 6 is installed in the O-ring groove of the valve seat assembly 3, and an internal O-ring seal 7 is installed in the O-ring groove at the lower end of the valve base 5 to prevent media leakage at the connection. The entire valve core assembly is connected to the valve body via threads on the valve seat 32 of the valve seat assembly 3. Before the electronic expansion valve starts working, the fluid medium enters the valve body through point E. When the valve opening command is issued, the stator coil drives the magnetic rotor to rotate. The threads first drive the inner valve core to move. After the inner valve core moves a certain distance, the entire valve needle assembly moves. The fluid medium enters the valve body through point F and also enters the upper cavity of the valve body through the thread gap. Due to the presence of the magnetic shielding tube, the fluid medium fills the upper cavity of the entire valve core assembly, thereby reducing the pressure difference between the upper and lower sides of the valve needle and reducing the resistance to valve needle movement. The small channel seal between the valve needles prevents internal leakage when the valve is closed (0%). When the electronic expansion valve is working, the high-pressure liquid fluid medium is throttled through the valve port, causing the pressure of the high-pressure fluid medium to drop and become a gas-liquid mixture, while releasing heat. The temperature and pressure sensors at the outlet end will input the collected temperature and pressure signals to the controller. The controller will calculate according to the relevant control program and output a signal to the electronic expansion valve, which will change the current in the winding coil of the stator coil, thereby generating a changing excitation magnetic field inside the coil. The magnetic rotor assembly 2 rotates under the action of the excitation magnetic field, thereby driving the magnetic rotor assembly 2 to move, and further driving the valve needle assembly 4 to move through the thread transmission, so as to realize the change of the opening of the electronic expansion valve port, thereby achieving the purpose of regulating the flow and pressure of the fluid medium.

[0022] The main functions achieved by this utility model are: 1. The valve needle assembly is internally equipped with an inner valve core. The inner valve core has a threaded structure that directly matches the threads on the rotor. The valve is driven by a combination of screw thread and inner valve core thread. The front end of the inner valve core has a sealing structure that works with the valve needle to achieve a seal. When the inner valve core moves a certain distance, the valve needle is also lifted by the thread. This design is simple and ensures sealing performance while also allowing for precise control of refrigerant flow.

[0023] 2. The valve needle is designed with two-end stop structures that mate with the guide hole at valve seat 32c, enabling quick installation of the valve needle while preventing radial rotation. 3. A valve needle spring is used as a downward buffer to prevent the valve needle from suddenly stopping when it encounters the lower stroke limit during valve closing, which would generate a large inertial force, cause the threads to jam, and result in excessive axial force on the structure, leading to valve jamming. By accurately calculating the spring force, precise flow control can be achieved at small openings.

[0024] 4. The electronic expansion valve is equipped with a magnetic shielding tube and a dynamic seal. Before starting work, the fluid medium enters the upper cavity of the valve body through the balance flow channel at point F and the thread gap. Due to the presence of the magnetic shielding tube, the fluid medium will fill the upper cavity of the entire valve seat assembly. Furthermore, due to the presence of the inner valve core ring and the inner leakage O-ring, the fluid medium will not leak. This reduces the pressure difference between the upper and lower sides of the valve needle, reduces the resistance to valve needle movement, and increases the valve's service life.

[0025] 5. High structural integration: The valve not only achieves on / off and shut-off functions but also precise flow control, making assembly more convenient, promoting lightweight design, and featuring advanced parts processing technology for lower costs.

[0026] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. A large-diameter electronic expansion valve for precise flow regulation, comprising a magnetic insulated tube assembly (1), a magnetic rotor assembly (2), a valve seat component (3), a valve needle assembly (4), a valve base (5), an external leakage O-ring seal (6), and an internal leakage O-ring seal (7), characterized in that, The magnetic shielding tube assembly (1) consists of a magnetic shielding ring (11) and a sliding bearing assembly (12). The sliding bearing assembly (12) consists of a sliding bearing (121), a spring guide rail (122), and a slip ring (123). The sliding bearing (121) and the magnetic shielding ring (11) are interference-fitted. The sliding bearing (121) is pressed into the inner cavity of the magnetic shielding ring (11). The top flat end (121a) of the sliding bearing (121) contacts and limits the contact with the top flat surface 11a of the magnetic shielding ring (11). The top end (121b) of the sliding bearing (121) is designed with a clearance structure at the top arc position 11b of the magnetic shielding ring (11). The lower end of the sliding bearing (121) has a small groove (121c) for positioning during assembly. The upper end of the sliding bearing (121) has four feature grooves (121d), which are the limiting feature grooves after being riveted to the magnetic isolation ring (11). A is the riveting point. The spring guide rail (122) and the slip ring (123) are sleeved on the shaft tube of the sliding bearing (121). The upper part 122a of the spring guide rail (122) is fixed in the groove (121e) of the sliding bearing (121). The slip ring (123) moves axially along the sliding bearing (121). The movement of the slip ring (123) is controlled by the rotation of the magnetic rotor assembly (2).

2. The large-diameter electronic expansion valve for precise flow regulation as described in claim 1, characterized in that, The magnetic rotor assembly (2) consists of a magnetic rotor support frame (21), a magnetic ring (22), a screw (23) and a brake rod (24). The brake rod (24) adopts a three-jaw structure design. The screw (23) and the brake rod (24) are pressed together and then laser welded at point B. The screw (23) and the magnetic ring (22) are connected by injection molding. The magnetic ring (22) is made of neodymium iron boron and is processed by bonding process.

3. The large-diameter electronic expansion valve for precise flow regulation as described in claim 2, characterized in that, The valve seat component (3) consists of a roller bearing (31) and a valve seat (32). The roller bearing (31) is installed in the bearing chamber 32a of the valve seat (32). The screw (23) on the magnetic rotor assembly (2) is interference-fitted with the inner ring of the roller bearing (31). A raised chamfer is provided at the valve seat 32b. The valve seat (32) is designed with a valve seat (32c) inside. The valve needle assembly (4) is guided by the valve seat cavity (32d).

4. The large-diameter electronic expansion valve for precise flow regulation as described in claim 1, characterized in that, The valve needle assembly (4) consists of a stop ring (41), an inner valve core (42), a valve needle spring (43), and a valve needle (44). The valve needle (44) has four balance holes (44c). The upper part of the valve needle (44) is designed with a two-end stop structure (44a). The two-end stop structure (44a) cooperates with the valve seat (32c) inside the valve seat component (3). The upper part of the valve needle (44) has a groove (44b) that cooperates with the inner valve core (42). The inner valve core (42) and the valve needle (44) are sealed by a C structure. The bottom of the thread of the inner valve core (42) is designed with 42b. The stop ring (41) cooperates with the inner valve core (42) to form a contour design. The valve needle spring (43) plays a buffering role.

5. The large-diameter electronic expansion valve for precise flow regulation as described in claim 4, characterized in that, The inner valve core (42) is made of SUS304.

6. The large-diameter electronic expansion valve for precise flow regulation as described in claim 1, characterized in that, The screw (23) thread is machined using the thread rolling process.

7. The large-diameter electronic expansion valve for precise flow regulation as described in claim 1, characterized in that, The sliding bearing (121) has a through-hole design inside.

8. The large-diameter electronic expansion valve for precise flow regulation as described in claim 1, characterized in that, The magnetic shielding ring (11) is made of deep-drawn SUS304 stainless steel.

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