Valve element structure of electronic expansion valve

Abstract

The invention discloses a valve core structure of an electronic expansion valve, and relates to the technical field of electronic expansion valves, the valve core structure comprises a valve sleeve and a screw rod, a valve needle sleeve is slidably sleeved in the valve sleeve, a top plate is fixedly connected to the top of the valve needle sleeve, the screw rod is arranged on the upper surface of the top plate, a buffer spring is placed in the valve needle sleeve, and the buffer spring is fixedly connected to the top of the valve needle sleeve. The bottom of the valve needle sleeve is fixedly sleeved with a sealing cover, a sleeving hole is formed in the middle of the sealing cover, the sealing cover is slidably sleeved with a valve needle through the sleeving hole, a reset mechanism is arranged on the outer side of the lead screw, and when the lead screw moves up and down, the reset mechanism drives the valve needle sleeve to move up and down along with the lead screw. On the premise of ensuring the functions, not only are the welding steps reduced, but also the number of parts is optimized, the cost is saved, and meanwhile the production efficiency is improved.

Description

Technical Field

[0001] This invention relates to the field of electronic expansion valve technology, and more particularly to an electronic expansion valve core structure. Background Technology

[0002] Electronic expansion valves are widely used in refrigeration systems as throttling elements to regulate refrigerant flow. The basic principle of an electronic expansion valve is that an energized coil surrounding the valve housing drives a rotor assembly to rotate, which in turn drives a lead screw in the nut assembly to produce a circular motion. The axial movement of the lead screw is transmitted to the valve needle through an elastic component. The valve needle moves up and down, causing its head to approach or move away from the valve port, thereby changing the flow area of ​​the valve port and achieving refrigerant flow regulation and on / off functions.

[0003] In the prior art, the valve core structure of an electronic expansion valve is as follows: Figure 18 and Figure 19 As shown, the valve core structure includes a valve needle, an upper spring base, a lower spring base, a cover, and a spring. The valve needle has a valve core cavity, and the lower spring base and spring are located within the valve core cavity. The cover and upper spring base are separate components. First, the upper spring base needs to be welded to the lower end of the lead screw via welding point C. Then, the upper spring base is installed into the valve core cavity, with the cover positioned above the conical surface of the upper spring base. Finally, the cover and valve needle are welded together via welding point D. Therefore, the valve core structure of the existing electronic expansion valve not only requires multiple welding operations but also has numerous mounting components, making the assembly process cumbersome. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies by proposing a valve core structure for an electronic expansion valve.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: An electronic expansion valve core structure includes a valve sleeve and a lead screw. A valve needle sleeve is slidably sleeved inside the valve sleeve. A top plate is fixedly connected to the top of the valve needle sleeve. A lead screw is provided on the upper surface of the top plate. A buffer spring is placed inside the valve needle sleeve. A cover is fixedly sleeved to the bottom of the valve needle sleeve. A sleeve hole is opened in the middle of the cover. A valve needle is slidably sleeved on the cover through the sleeve hole. A reset mechanism is provided on the outside of the lead screw. When the lead screw moves up and down, the reset mechanism drives the valve needle sleeve to move up and down with the lead screw. A valve block is fitted onto the outer wall of the valve sleeve. An output port is provided on one side of the valve block, and an input port is provided on the other side of the valve block. An installation groove is provided on the upper surface of the valve block. The output port is connected to the input port through the installation groove, and the valve sleeve is located in the installation groove.

[0006] Preferably, the bottom end of the lead screw is spherical.

[0007] Preferably, the valve needle sleeve is integrally formed with the top plate, and the outer wall of the top plate is provided with a breathing hole.

[0008] Preferably, the upper surface of the cap is fixedly connected with a snap-fit ​​protrusion, the snap-fit ​​protrusion is integrally formed with the cap, the outer wall of the snap-fit ​​protrusion has a through hole communicating with the sleeve hole, the size of the snap-fit ​​protrusion matches the size of the valve needle sleeve, the snap-fit ​​protrusion is located inside the valve needle sleeve, and the snap-fit ​​protrusion and the valve needle sleeve are sleeved together.

[0009] Preferably, the sidewall of the cap is welded to the bottom outer wall of the valve needle sleeve.

[0010] Preferably, a limiting block is fixedly connected to the top of the valve needle, the limiting block is integrally formed with the valve needle, the limiting block is located inside the valve needle sleeve, the limiting block and the valve needle sleeve are in clearance fit, and the limiting block is in contact with the bottom of the buffer spring.

[0011] Preferably, a positioning protrusion is fixedly connected to the upper surface of the limiting block, the limiting block and the positioning protrusion are integrally formed, and the positioning protrusion is sleeved with the buffer spring.

[0012] Preferably, the diameter of the top plate is larger than the diameter of the valve needle sleeve, and the reset mechanism includes a first reset spring, which is sleeved on the outside of the valve needle sleeve. The top end of the first reset spring contacts the lower surface of the top plate, and the bottom end of the first reset spring contacts the inner wall of the valve sleeve.

[0013] Preferably, the diameter of the top plate is equal to the diameter of the valve needle sleeve, the reset mechanism includes a second reset spring, the valve needle and the second reset spring are sleeved together, the top end of the second reset spring contacts the lower surface of the cover, and the bottom end of the second reset spring contacts the inner wall of the valve sleeve.

[0014] Preferably, the valve block has an internal thread at the mounting groove, and the valve block is threaded with a locking nut through the internal thread, and the locking nut is sleeved with the valve sleeve.

[0015] The beneficial effects of this invention are as follows: In this invention, the design of the lead screw, valve needle sleeve, buffer spring, cover, valve needle, and reset mechanism improves the point contact between the lead screw and the valve needle sleeve. Compared with the prior art, this reduces the need for welding the lead screw to the spring base in the original design, and the entire valve core structure only needs to be welded once. At the same time, the various structures in this valve core structure are simple and compact. While ensuring its function, it not only reduces the welding steps but also optimizes the number of parts, saving costs and improving production efficiency. Attached Figure Description

[0016] Figure 1This is a schematic diagram of the lead screw, valve block, and locking nut of an electronic expansion valve core structure according to the present invention.

[0017] Figure 2 This is a top view of the lead screw, valve block, and locking nut of an electronic expansion valve core structure according to the present invention.

[0018] Figure 3 This invention relates to an electronic expansion valve core structure. Figure 2 Cross-sectional view of CC.

[0019] Figure 4 This is a schematic diagram of the valve block structure of an electronic expansion valve core structure according to the present invention.

[0020] Figure 5 This is a schematic diagram of the valve core structure of an electronic expansion valve according to the present invention.

[0021] Figure 6 This is a front view of the valve core structure of an electronic expansion valve according to the present invention.

[0022] Figure 7 This invention relates to an electronic expansion valve core structure. Figure 6 Cross-sectional view of BB.

[0023] Figure 8 This is a schematic diagram of the valve needle sleeve of an electronic expansion valve core structure according to the present invention.

[0024] Figure 9 This is a schematic diagram of the cover structure of an electronic expansion valve core structure according to the present invention.

[0025] Figure 10 This is a schematic diagram of the valve needle structure of an electronic expansion valve core structure according to the present invention.

[0026] Figure 11 This is a schematic diagram of the valve needle sleeve, buffer spring, cover, and valve needle of an electronic expansion valve core structure according to the present invention.

[0027] Figure 12 This is a schematic diagram of the valve needle sleeve and cover of an electronic expansion valve core structure according to the present invention.

[0028] Figure 13 This invention relates to an electronic expansion valve core structure. Figure 12 A schematic diagram of the structure at point A in the middle.

[0029] Figure 14 This is a flowchart illustrating the assembly process of the valve core structure of an electronic expansion valve according to the present invention.

[0030] Figure 15This is a schematic diagram of the valve sleeve, valve needle sleeve, and return spring of an electronic expansion valve core structure according to the present invention.

[0031] Figure 16 This is a schematic diagram of the valve needle sleeve reset spring in Embodiment 2 of the present invention.

[0032] Figure 17 This is a schematic diagram of the valve needle sleeve in Embodiment 2 of the present invention.

[0033] Figure 18 This is a schematic diagram of the valve core structure of an electronic expansion valve in the prior art.

[0034] Figure 19 This is a partial structural diagram of the valve core structure in the prior art of electronic expansion valves.

[0035] Labels in the diagram: 1. Valve sleeve; 2. Lead screw; 3. Valve needle sleeve; 301. Top plate; 302. Breathing hole; 4. Buffer spring; 5. Cover; 501. Socket hole; 502. Snap-fit ​​protrusion; 6. Valve needle; 601. Limiting block; 602. Positioning protrusion; 7. Reset mechanism; 701. First reset spring; 702. Second reset spring; 8. Valve block; 801. Output port; 802. Input port; 803. Mounting groove; 804. Internal thread; 9. Locking nut. Detailed Implementation

[0036] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0037] Example 1, as shown in the attached document Figure 1 To be continued Figure 15 As shown, an electronic expansion valve core structure includes a valve sleeve 1 and a lead screw 2. A valve needle sleeve 3 is slidably sleeved inside the valve sleeve 1. A top plate 301 is fixedly connected to the top of the valve needle sleeve 3. The lead screw 2 is provided on the upper surface of the top plate 301. A buffer spring 4 is placed inside the valve needle sleeve 3. A cover 5 is fixedly sleeved at the bottom of the valve needle sleeve 3. A sleeve hole 501 is opened in the middle of the cover 5. A valve needle 6 is slidably sleeved on the cover 5 through the sleeve hole 501. A reset mechanism 7 is provided on the outside of the lead screw 2. When the lead screw 2 moves up and down, the reset mechanism 7 drives the valve needle sleeve 3 to move up and down with the lead screw 2. A valve block 8 is fitted onto the outer wall of the valve sleeve 1. An output port 801 is provided on one side of the valve block 8, and an input port 802 is provided on the other side of the valve block 8. An installation groove 803 is provided on the upper surface of the valve block 8. The output port 801 is connected to the input port 802 through the installation groove 803. The valve sleeve 1 is located in the installation groove 803.

[0038] In the above technical solution, the buffer spring 4 is located inside the valve needle sleeve 3. The main function of the buffer spring 4 is to prevent the valve needle 6 from making a hard impact on the valve port at the bottom of the valve sleeve 1, which would damage the valve port, and to ensure that the preload force when the valve port is closed is controllable. When the lead screw 2 moves downward, it generates a downward force that acts directly on the upper surface of the top plate 301. The reset mechanism 7 is compressed, and the top plate 301 overcomes the upward force of the reset mechanism 7, causing the top plate 301 and the valve needle sleeve 3 to move downward with the lead screw 2. The valve needle sleeve 3 drives the valve needle 6 to move downward. When the bottom conical surface of the valve needle 6 makes mechanical contact with the valve port at the bottom of the valve sleeve 1, the valve port closes. At this time, when the valve needle sleeve 3 continues to move downward under the action of the lead screw 2, the internal buffer spring 4 of the valve needle sleeve 3 is further compressed. A certain spring force is applied to the buffer spring 4 through the limit block 601, which further strengthens the sealing effect of the valve port at the bottom of the valve sleeve 1. When the lead screw 2 moves upward, the valve needle sleeve 3 and the top plate 301 are subjected to the upward force of the reset mechanism 7. The reset mechanism 7 drives the valve needle sleeve 3 to move upward with the lead screw 2. The valve needle sleeve 3 drives the valve needle 6 to move upward. The valve needle 6 does not contact the valve sleeve 1. At this time, the valve port at the bottom of the valve sleeve 1 is opened. At this time, the fluid enters the inner valve sleeve 1 through the inlet port 802 and is discharged through the outlet port 801.

[0039] As attached Figure 7 As shown, the bottom end of the lead screw 2 is spherical.

[0040] In the above technical solution, the bottom end of the lead screw 2 is designed as a spherical surface, which can reduce the wear between the lead screw 2 and the top plate 301 when the lead screw 2 rotates.

[0041] As attached Figure 8 As shown, the valve needle sleeve 3 is integrally formed with the top plate 301, and the outer wall of the top plate 301 is provided with a breathing hole 302.

[0042] In the above technical solution, a vent 302 is provided on the top of the top plate 301. The vent 302 is used to balance the internal cavity of the valve needle sleeve 3 with the external pressure.

[0043] As attached Figure 9 To be continued Figure 13 As shown, a snap-fit ​​protrusion 502 is fixedly connected to the upper surface of the cover 5. The snap-fit ​​protrusion 502 is integrally formed with the cover 5. The outer wall of the snap-fit ​​protrusion 502 has a through hole that communicates with the sleeve hole 501. The size of the snap-fit ​​protrusion 502 matches the size of the valve needle sleeve 3. The snap-fit ​​protrusion 502 is located inside the valve needle sleeve 3 and is sleeved with the valve needle sleeve 3. The side wall of the cover 5 is welded to the bottom outer wall of the valve needle sleeve 3.

[0044] In the above technical solution, the snap-fit ​​protrusion 502 at the cap 5 fits seamlessly with the valve needle sleeve 3. The main function of the cap 5 is to guide and radially limit the valve needle 6. The outer wall of the cap 5 is welded to the bottom outer wall of the valve needle sleeve 3 through welding point S. Figure 9 As shown.

[0045] As attached Figure 10 To be continued Figure 11 As shown, a limiting block 601 is fixedly connected to the top of the valve needle 6. The limiting block 601 is integrally formed with the valve needle 6. The limiting block 601 is located inside the valve needle sleeve 3. The limiting block 601 and the valve needle sleeve 3 are in clearance fit. The limiting block 601 is in contact with the bottom of the buffer spring 4.

[0046] In the above technical solution, through the design of the limiting block 601, the limiting block 601 is in clearance fit with the valve needle sleeve 3. When the valve needle 6 moves up and down, the limiting block 601 achieves the guiding function of the valve needle 6.

[0047] As attached Figure 10 To be continued Figure 11 As shown, a positioning protrusion 602 is fixedly connected to the upper surface of the limiting block 601. The limiting block 601 and the positioning protrusion 602 are integrally formed, and the positioning protrusion 602 is sleeved with the buffer spring 4.

[0048] In the above technical solution, the top of the valve needle 6 is provided with a limiting block 601 and a positioning protrusion 602 for mounting and positioning the buffer spring 4.

[0049] As attached Figure 8 and attached Figure 15 As shown, the diameter of the top plate 301 is larger than the diameter of the valve needle sleeve 3. The reset mechanism 7 includes a first reset spring 701, which is sleeved on the outside of the valve needle sleeve 3. The top end of the first reset spring 701 contacts the lower surface of the top plate 301, and the bottom end of the first reset spring 701 contacts the inner wall of the valve sleeve 1.

[0050] In the above technical solution, when the lead screw 2 moves upward, the valve needle sleeve 3 and the top plate 301 move upward in tandem under the action of the first return spring 701, which is used to reset the valve needle sleeve 3.

[0051] As attached Figure 1 and attached Figure 4 As shown, the valve block 8 is provided with an internal thread 804 at the mounting groove 803. The valve block 8 is threaded with a locking nut 9 through the internal thread 804. The locking nut 9 is sleeved with the valve sleeve 1.

[0052] In the above technical solution, the locking nut 9 is sleeved on the outside of the valve sleeve 1, and the locking nut 9 is screwed into the internal thread 804. A certain torque is applied to the locking nut 9 to lock and fix the valve sleeve 1 and the valve block 8.

[0053] The specific usage and function of this embodiment are as follows: During assembly, the buffer spring 4 is first installed into the valve needle sleeve 3; then the valve needle 6 is installed into the valve needle sleeve 3, and the valve needle 6 contacts the buffer spring 4; finally, the cover 5 and the valve needle 6 are sleeved together, and the cover 5 is pressed into one end of the valve needle sleeve 3, and the connection between the cover 5 and the valve needle sleeve 3 is circumferentially welded through the welding point S.

[0054] Please refer to the above structure and process. Figure 12-14 .

[0055] When the present invention is used, when the lead screw 2 moves downward, the lead screw 2 generates a downward force, which acts directly on the upper surface of the top plate 301. The first return spring 701 is compressed, and the top plate 301 overcomes the return spring force of the first return spring 701, causing the top plate 301 and the valve needle sleeve 3 to move downward with the lead screw 2. The valve needle sleeve 3 drives the valve needle 6 to move downward. When the bottom conical surface of the valve needle 6 makes mechanical contact with the valve port at the bottom of the valve sleeve 1, the valve port closes. At this time, when the valve needle sleeve 3 continues to move downward under the action of the lead screw 2, the buffer spring 4 inside the valve needle sleeve 3 is further compressed. A certain spring force is applied to the buffer spring 4 through the limiting block 601, which further strengthens the sealing effect of the valve port at the bottom of the valve sleeve 1. When the lead screw 2 moves upward, the valve needle sleeve 3 and the top plate 301 are under the force of the first return spring 701. The first return spring 701 drives the valve needle sleeve 3 to move upward with the lead screw 2. The valve needle sleeve 3 drives the valve needle 6 to move upward. The valve needle 6 does not contact the valve sleeve 1. At this time, the valve port at the bottom of the valve sleeve 1 is opened. At this time, the fluid enters the inner valve sleeve 1 through the inlet port 802 and is discharged through the outlet port 801.

[0056] Please refer to the above structure and process. Figure 1-15 .

[0057] It is worth mentioning that valve sleeve 1 and lead screw 2 are conventional products in the prior art and can be purchased on the market. They are mature technologies in this field and have been fully disclosed, so they will not be repeated in the specification.

[0058] Example 2, as shown in the attached document Figure 16 To be continued Figure 17 The image shows the second embodiment of the present invention, which differs from the first embodiment in that: The diameter of the top plate 301 is equal to the diameter of the valve needle sleeve 3. The reset mechanism 7 includes a second reset spring 702. The valve needle 6 and the second reset spring 702 are sleeved together. The top end of the second reset spring 702 contacts the lower surface of the cover 5, and the bottom end of the second reset spring 702 contacts the inner wall of the valve sleeve 1.

[0059] In the above technical solution, this embodiment is another electronic expansion valve core structure. In this electronic expansion valve core structure, the second return spring 702 is installed between the cover 5 and the valve port at the bottom of the valve sleeve 1. When the lead screw 2 moves upward, the valve needle sleeve 3 and the top plate 301 move upward under the action of the second return spring 702. The second return spring 702 is used to reset the valve needle sleeve 3.

[0060] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A valve core structure for an electronic expansion valve, comprising a valve sleeve (1) and a lead screw (2), characterized in that, A valve needle sleeve (3) is slidably sleeved inside the valve sleeve (1). A top plate (301) is fixedly connected to the top of the valve needle sleeve (3). A lead screw (2) is provided on the upper surface of the top plate (301). A buffer spring (4) is placed inside the valve needle sleeve (3). A cover (5) is fixedly sleeved at the bottom of the valve needle sleeve (3). A sleeve hole (501) is opened in the middle of the cover (5). A valve needle (6) is slidably sleeved through the sleeve hole (501) of the cover (5). A reset mechanism (7) is provided on the outside of the lead screw (2). When the lead screw (2) moves up and down, the reset mechanism (7) drives the valve needle sleeve (3) to move up and down with the lead screw (2). The valve sleeve (1) is fitted with a valve block (8) on its outer wall. The valve block (8) has an output port (801) on one side and an input port (802) on the other side. The valve block (8) has an installation groove (803) on its upper surface. The output port (801) is connected to the input port (802) through the installation groove (803). The valve sleeve (1) is located in the installation groove (803).

2. The electronic expansion valve core structure according to claim 1, characterized in that, The bottom end of the lead screw (2) is spherical.

3. The electronic expansion valve core structure according to claim 1, characterized in that, The valve needle sleeve (3) is integrally formed with the top plate (301), and the outer wall of the top plate (301) is provided with a breathing hole (302).

4. The valve core structure of an electronic expansion valve according to claim 1, characterized in that, The upper surface of the cover (5) is fixedly connected with a snap-fit ​​protrusion (502). The snap-fit ​​protrusion (502) is integrally formed with the cover (5). The outer wall of the snap-fit ​​protrusion (502) is provided with a through hole that communicates with the sleeve hole (501). The size of the snap-fit ​​protrusion (502) matches the size of the valve needle sleeve (3). The snap-fit ​​protrusion (502) is located inside the valve needle sleeve (3). The snap-fit ​​protrusion (502) and the valve needle sleeve (3) are sleeved together.

5. The valve core structure of an electronic expansion valve according to claim 1, characterized in that, The side wall of the cap (5) is welded to the bottom outer wall of the valve needle sleeve (3).

6. The valve core structure of an electronic expansion valve according to claim 1, characterized in that, The top of the valve needle (6) is fixedly connected to a limiting block (601). The limiting block (601) is integrally formed with the valve needle (6). The limiting block (601) is located inside the valve needle sleeve (3). The limiting block (601) and the valve needle sleeve (3) are in clearance fit. The limiting block (601) is in contact with the bottom of the buffer spring (4).

7. The valve core structure of an electronic expansion valve according to claim 6, characterized in that, The upper surface of the limiting block (601) is fixedly connected with a positioning protrusion (602). The limiting block (601) and the positioning protrusion (602) are integrally formed. The positioning protrusion (602) and the buffer spring (4) are sleeved together.

8. The valve core structure of an electronic expansion valve according to claim 1, characterized in that, The diameter of the top plate (301) is larger than the diameter of the valve needle sleeve (3). The reset mechanism (7) includes a first reset spring (701), which is sleeved on the outside of the valve needle sleeve (3). The top end of the first reset spring (701) contacts the lower surface of the top plate (301), and the bottom end of the first reset spring (701) contacts the inner wall of the valve sleeve (1).

9. The valve core structure of an electronic expansion valve according to claim 1, characterized in that, The diameter of the top plate (301) is equal to the diameter of the valve needle sleeve (3). The reset mechanism (7) includes a second reset spring (702). The valve needle (6) and the second reset spring (702) are sleeved together. The top end of the second reset spring (702) contacts the lower surface of the cover (5), and the bottom end of the second reset spring (702) contacts the inner wall of the valve sleeve (1).

10. The valve core structure of an electronic expansion valve according to claim 1, characterized in that, The valve block (8) is provided with an internal thread (804) at the mounting groove (803). The valve block (8) is threaded with a locking nut (9) through the internal thread (804). The locking nut (9) is sleeved with the valve sleeve (1).

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