Valve needle assembly, electronic expansion valve, and refrigeration device

Abstract

The application discloses a valve needle assembly, an electronic expansion valve and a refrigeration device, wherein the valve needle assembly comprises a valve needle, a limiting sleeve ring, a bearing, a valve rod and an elastic piece, the valve needle has opposite first and second ends, the first end is used for being detachably mounted on a valve port of the electronic expansion valve, and the second end is provided with a mounting groove; the limiting sleeve ring is fixedly connected to the second end, and at least one of the second end and the limiting sleeve ring is provided with the mounting groove; the bearing is arranged in the mounting groove, and two end faces of an outer ring of the bearing are respectively limited and abutted by the valve needle and the limiting sleeve ring; one end of the elastic piece is connected to the valve rod, and the other end is connected to the bearing; and the valve rod drives the valve needle to axially move through circumferential movement. The technical scheme aims to solve the technical problem that the valve needle is prone to being abraded due to rotation relative to the valve port in the prior art.

Description

[0001] This application is a divisional application of application number 202210093242.4, with the parent application filed on January 26, 2022; the invention is entitled "Valve needle assembly, electronic expansion valve and refrigeration equipment". Technical Field

[0002] This invention relates to the field of electronic expansion valves, and particularly to a valve needle assembly, an electronic expansion valve, and a refrigeration device. Background Technology

[0003] Currently, electronic expansion valves utilize the principle of stepper motors, driving a magnetic rotor to rotate via a coil. This rotational motion of the magnetic rotor is then converted into the axial motion of the valve stem, which in turn drives the connected valve needle to rise or fall, controlling the flow rate of the electronic expansion valve.

[0004] In related technologies, electronic expansion valves mainly include a rotor, a valve stem, a nut, and a valve needle. The valve stem is rotatably connected to the nut, and the valve needle is located at the lower end of the valve stem. The rotor drives the valve stem to move axially, which in turn drives the valve needle to move axially, thereby achieving the purpose of sealing or opening the valve port. However, with this structure, when sealing or opening the valve port, the valve needle rotates relative to the valve port, causing wear on both the valve needle and the valve port, thus shortening the service life of the valve needle.

[0005] The above content is only used to help understand the technical solution of the invention and does not represent an admission that the above content is prior art. Summary of the Invention

[0006] The main objective of this invention is to provide a valve needle assembly that addresses the technical problem in the prior art where the valve needle rotates relative to the valve port, leading to easy wear of the valve needle.

[0007] To achieve the above objectives, the present invention provides a valve needle assembly for use in an electronic expansion valve, comprising:

[0008] The valve needle has a first end and a second end, the first end being detachably mounted to the valve port of the electronic expansion valve, and the second end being provided with a mounting groove.

[0009] A limiting collar is fixedly connected to the second end, and at least one of the second end and the limiting collar is provided with a mounting groove;

[0010] The bearing is disposed in the mounting groove, and the two end faces of the outer ring of the bearing are respectively limited and abutted by the valve needle and the limiting collar;

[0011] The valve stem, passing through the limiting collar, is movably inserted into the inner ring of the bearing; and

[0012] An elastic element, one end of which is connected to the valve stem and the other end of which is connected to the bearing;

[0013] The valve stem drives the valve needle to move axially through circumferential motion.

[0014] Optionally, the second end is provided with a mounting groove, which has a first groove segment and a second groove segment distributed in the axial direction. The inner diameter of the first groove segment is larger than the inner diameter of the second groove segment, and a limiting step is formed at the connection between the first groove segment and the second groove segment. The limiting step limits and abuts against the end face of the outer ring of the bearing near the first end.

[0015] Optionally, the end face of the limiting collar near the first end is limited and abuts against the end face of the outer ring of the bearing away from the first end, and the limiting collar is fixedly connected to the groove wall of the mounting groove at the second end.

[0016] Optionally, the limiting collar is inserted into the first groove segment.

[0017] Optionally, the limiting collar is connected to the groove wall of the first groove segment by welding.

[0018] Optionally, the valve needle assembly further includes a drive collar fixedly sleeved on the end of the valve needle, the drive collar being located on the side of the bearing closer to the first end.

[0019] Optionally, the valve needle has a positioning step at its end, and the drive collar abuts against the positioning step.

[0020] Optionally, the valve needle includes a needle body and a connecting part connected together, with the first end located on the needle body and the second end located on the connecting part. The needle body and the connecting part are integrally formed, or the needle body and the connecting part are separately formed and then fixedly connected.

[0021] Optionally, the elastic element is configured as a spring, and the peripheral wall of the valve stem is provided with a flange on the side of the bearing away from the first end. The spring is sleeved on the valve stem, with one end abutting against the flange and the other end naturally abutting against the end face of the bearing.

[0022] The present invention also proposes an electronic expansion valve, comprising:

[0023] The nut has a mounting hole;

[0024] The aforementioned valve needle assembly has a valve stem that passes through the mounting hole and is threadedly connected to the nut.

[0025] The present invention also proposes a refrigeration device, including the aforementioned electronic expansion valve.

[0026] In this invention, the bearing outer ring is fixedly mounted in the mounting groove by limiting the bearing on both sides of the bearing axially using a valve needle and a limiting collar. Therefore, when the valve stem rotates circumferentially and axially to drive the valve needle, even if the inner ring of the bearing is driven to rotate with the valve stem, the outer ring of the bearing, fixedly connected to the valve needle, remains stationary circumferentially, and the valve needle will not be driven to rotate circumferentially. In this invention, by cooperating with the bearing, the circumferential movement transmitted from the valve stem to the valve needle is counteracted, so that the valve needle only receives the axial movement transmitted by the valve stem and does not rotate relative to the valve port. This helps reduce wear between the valve needle and the valve port, thereby ensuring the reliability of the electronic expansion valve. Specifically, the valve stem drives the valve needle to move axially through the elastic element, and the valve needle can move axially at least relative to the bearing. In this way, when the valve needle abuts against the valve port, the valve stem can continue to move downward relative to the valve needle, thereby compressing the elastic element so that the elastic element can provide a preload force for the valve needle, so that the valve needle can stably abut against the valve port. At the same time, it can also avoid the valve needle from excessively squeezing the valve port, which would cause wear between the valve needle and the valve port. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0028] Figure 1 This is a schematic diagram of the structure of an embodiment of the valve needle assembly of the present invention;

[0029] Figure 2 for Figure 1 A magnified view of a section at point F in the middle;

[0030] Figure 3 for Figure 1 A magnified view of a section at point G in the middle;

[0031] Figure 4 This is a schematic diagram of the structure of an embodiment of the electronic expansion valve of the present invention;

[0032] Figure 5 for Figure 4 A magnified view of a section at point A in the middle;

[0033] Figure 6 for Figure 4 A magnified view of a section at point B in the middle;

[0034] Figure 7 for Figure 4 A magnified view of a section at point C;

[0035] Figure 8 for Figure 4 A magnified view of a section at point D;

[0036] Figure 9 for Figure 4 A magnified view of a section at point E in the middle.

[0037] Explanation of icon numbers:

[0038] 100 valve housing 400 Guide collar 101 outer cover 401 Second guide hole 102 valve seat 402 First clearance hole 103 valve chamber 403 Second clearance hole 1031 First valve chamber 410 Install steps 1032 Second valve chamber 411 Third step surface 104 valve port 412 Fourth step surface 105 Refrigerant passing through 413 Second guide surface 110 Staircase space 414 Transition surface 111 First step surface 420 Guide cone surface 112 Second step surface 430 Connection surface 113 First guiding surface 440 air vent 200 Nut 500 valve needle 210 Mounting holes 501 First end 211 Threaded hole 502 Second end 212 First guide hole 510 needle body 300 valve stem 511 Main body 310 elastic element 512 tip 320 Flange 520 Connection part 330 Positioning steps 530 Mounting slot 600 bearings 531 Make room 800 Drive collar 532 Limiting step 810 Second connecting section 700 Limiting ring 820 Second guide section 710 First guiding section 830 transition section 720 First connecting section 900 Magnetic rotor

[0039] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0040] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0041] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0042] The terms "connection," "installation," and "fixation" should be interpreted broadly. For example, "connection" can mean a fixed connection, a detachable connection, or an integral connection; it can mean a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of these terms in this invention based on the specific circumstances.

[0043] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, if the word "and / or" appears throughout the text, it means including three parallel solutions; for example, "A and / or B" includes solution A, solution B, or a solution that simultaneously satisfies A and B. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0044] This invention proposes an electronic expansion valve.

[0045] Please see Figure 4 The electronic expansion valve proposed in this invention includes a valve housing 100, a magnetic rotor 900, a nut 200, and a valve needle assembly. The valve housing 100 includes an outer cover 101 and a valve seat 102 fixedly connected to the outer cover 101. The outer cover 101 and the valve seat 102 enclose a valve cavity 103. The magnetic rotor 900, nut 200, and valve needle assembly are all disposed within the valve cavity 103. The magnetic rotor 900 is rotatable relative to the valve housing 100. The nut 200 is fixedly connected to the valve seat 102. The magnetic rotor 900 drives the valve needle assembly to move, thereby controlling the flow rate of the electronic expansion valve.

[0046] The structure of the valve needle assembly will be described below.

[0047] Please refer to the above as well. Figure 1 and Figure 4 The valve needle assembly includes: a valve needle 500, a limiting collar 700, a bearing 600, a valve stem 300, and an elastic element 310. The valve needle 500 has a first end 501 and a second end 502 facing each other. The first end 501 is detachably mounted to the valve port 104 of the electronic expansion valve. The limiting collar 700 is fixedly connected to the second end 502. At least one of the second end 502 and the limiting collar 700 is provided with a mounting groove. The bearing 600 is disposed in the mounting groove. The two end faces of the outer ring of the bearing 600 are respectively abutted by the valve needle 500 and the limiting collar 700. The valve stem 300 passes through the limiting collar 700 and is movably inserted into the inner ring of the bearing 600. One end of the elastic element 310 is connected to the valve stem 300, and the other end is connected to the bearing 600.

[0048] It is understandable that either the limiting collar 700 or the second end 502 has a mounting groove for bearing installation, while the other end face directly abuts against one end face of the outer ring of the bearing 600. A limiting structure should be formed within the mounting groove to abut against the other end face of the outer ring of the bearing 600. Alternatively, the limiting collar 700 and the second end 502 may each have mounting grooves with opposing openings, and both mounting grooves may have limiting structures to abut against different end faces of the outer ring of the bearing 600. In both cases, the valve needle 500 and the limiting collar 700 can achieve limiting abutment against both end faces of the outer ring of the bearing 600.

[0049] Within the electronic expansion valve of the present invention, such as Figure 1 As shown, the nut 200 has a mounting hole 210 extending axially therein. The valve needle assembly passes through the mounting hole 210, and the valve stem 300 is threadedly connected to the nut 200. Specifically, the end of the valve stem 300 away from the first opening end has a threaded rod section. The mounting hole 210 includes a threaded hole 211 section adapted to the threaded rod section, and the threaded rod section mates with the threaded hole 211 section. The valve seat 102 has a valve port 104 corresponding to the valve needle 500, and the valve needle 500 is detachably installed in the valve port 104. Thus, the coil drives the magnetic rotor 900 to rotate, and the magnetic rotor 900 drives the valve stem 300 to rotate. Through the cooperation of the threaded rod section and the threaded hole 211 section, the valve stem 300 can simultaneously rotate circumferentially and move axially. The valve stem 300 then drives the valve needle 500 to move axially upward or downward, thereby controlling the flow rate of the electronic expansion valve.

[0050] In the valve needle assembly of the present invention, the outer ring of the bearing 600 is limited on both sides of the bearing 600 axially by the valve needle 500 and the limiting collar 700, thereby fixing the bearing 600 in the mounting groove. Thus, when the valve stem 300 rotates circumferentially and moves axially to drive the valve needle 500, even if the inner ring of the bearing 600 is driven to rotate with the valve stem 300, the outer ring of the bearing 600, which is fixedly connected to the valve needle 500, remains stationary circumferentially, and the valve needle 500 will not be driven to rotate circumferentially. In this invention, by cooperating the valve stem 300 with the bearing 600, the circumferential movement transmitted from the valve stem 300 to the valve needle 500 is counteracted, so that the valve needle 500 only receives the axial movement transmitted by the valve stem 300 and does not rotate relative to the valve port 104. This helps reduce wear between the valve needle 500 and the valve port 104, thereby ensuring the operational reliability of the electronic expansion valve. Specifically, the valve stem 300 drives the valve needle 500 to move axially via the elastic element 310, and the valve needle 500 can move axially at least relative to the bearing 600. Thus, when the valve needle 500 abuts against the valve port 104, the valve stem 300 can continue to move downward relative to the valve needle 500, thereby compressing the elastic element 310 so that the elastic element 310 can provide a preload force to the valve needle 500, thereby enabling the valve needle 500 to stably abut against the valve port 104. At the same time, it can also prevent the valve needle 500 from excessively squeezing the valve port 104, which would cause wear between the valve needle 500 and the valve port 104.

[0051] Specifically, the end of the elastic element 310 is connected to the end face of the inner ring of the bearing 600 away from the first end 501. Optionally, the end of the elastic element 310 is connected to the end faces of the valve stem 300 and the inner ring of the bearing 600 by abutment or insertion. The end of the elastic element 310 can directly abut against the end face of the valve stem 300 or the inner ring of the bearing 600, or it can indirectly abut against the end face of the valve stem 300 or the inner ring of the bearing 600 through other parts. Without loss of generality, such as... Figure 1 As shown, in this embodiment, the elastic element 310 is configured as a spring, and the peripheral wall of the valve stem 300 is provided with a flange portion 320. The spring is sleeved on the valve stem 300, with one end abutting against the flange portion 320 and the other end abutting against the end face of the bearing 600, so as to respectively realize the connection between the spring and the end faces of the valve stem 300 and the inner ring of the bearing 600. Of course, in other embodiments, the elastic element 310 can also be configured as a spring sheet, an elastic rubber sleeve, or an elastic silicone sleeve.

[0052] In some embodiments, please refer to the following: Figure 1 and Figure 2The second end 502 is provided with the mounting groove 530. The mounting groove 530 on the second end 502 has a first groove segment and a second groove segment distributed axially. The inner diameter of the first groove segment is larger than the inner diameter of the second groove segment. A limiting step 532 is formed at the connection between the first groove segment and the second groove segment. The limiting step 532 limits and abuts against the end face of the outer ring of the bearing 600 near the first end 501. Thus, the second groove segment forms a clearance space 531. The end of the valve stem 300 can protrude from the clearance space 531, so that the end of the valve stem 300 can move into the clearance space 531 to compress the spring, thereby providing a preload force to the valve needle 500. Of course, in other embodiments, the axial length of the bearing 600 can also be extended to provide sufficient space for the axial movement of the valve stem 300, ensuring that the spring can be compressed into place and provide sufficient preload force to the valve needle 500.

[0053] Furthermore, please refer to the following: Figure 1 and Figure 3 The end face of the limiting collar 700 near the first end 501 abuts against the end face of the outer ring of the bearing 600 away from the first end 501, and the limiting collar 700 is fixedly connected to the groove wall of the mounting groove 530 of the second end 502. Without loss of generality, the limiting collar 700 is inserted into the first groove segment and fixedly connected to the groove wall of the first groove segment by welding. Of course, in other embodiments, the end face of the bearing 600 may be flush with the end face of the first groove segment, and the limiting collar 700 fixed to the end face of the first groove segment can abut against the outer ring of the bearing 600. Furthermore, the limiting collar 700 can also be fixed to the mounting groove 530 by snap-fit.

[0054] It is understood that both the limiting step 532 and the limiting collar 700 should only abut against the end face of the outer ring of the bearing 600 to simultaneously restrict the axial movement and circumferential rotation of the outer ring of the bearing 600. The axial movement of the inner ring of the bearing 600 will also be restricted, but the circumferential rotation of the inner ring of the bearing 600 will not be affected, so as to ensure that the inner ring of the bearing 600 can be driven by the valve stem 300, thereby counteracting the circumferential rotation of the valve stem 300. Moreover, the cooperation between the limiting step 532 and the limiting collar 700 can provide a large clamping force in the axial direction of the bearing 600, which can prevent friction between the outer surface of the bearing 600 and the groove wall of the mounting groove 530, thereby ensuring that the bearing 600 can be stably installed in the mounting groove 530.

[0055] Furthermore, such as Figure 3As shown, the limiting collar 700 includes a first guide section 710 and a first connecting section 720 that are axially distributed and connected to each other. The first connecting section 720 is connected to the groove wall of the first groove section. The outer diameter of the first guide section 710 gradually decreases from the end connected to the first connecting section 720 toward the end away from the first connecting section 720. Thus, guided by the first guide section 710, the limiting collar 700 can be inserted into the mounting groove 530 with less effort. Of course, in other embodiments, the end face of the first groove section away from the second groove section may be provided with a guide structure, which can guide both the limiting collar 700 and the bearing 600 into the mounting groove 530.

[0056] Furthermore, such as Figure 3 As shown, each end of the first connecting segment 720 is connected to a first guide segment 710. That is, both ends of the limiting collar 700 have guide structures, so during assembly of the limiting collar 700, it is not necessary to distinguish the direction; either end of the limiting collar 700 can be guided by the first guide segment 710 when inserted into the mounting groove 530. Thus, by implementing a foolproof design for the limiting collar 700, the production efficiency of the electronic expansion valve of this invention can be improved.

[0057] In some embodiments, such as Figure 1 As shown, the valve needle assembly also includes a drive collar 800 fixedly sleeved on the end of the valve needle 500. The drive collar 800 is located on the side of the bearing 600 near the first end 501 and is detachably abutted against the end face of the bearing 600. Thus, when the valve stem 300 moves axially upward, the limiting collar 700 abuts against the end face of the bearing 600, and the limiting collar 700 is driven axially upward by the bearing 600. The bearing 600 is subjected to a pushing force and will also move upward accordingly. The valve needle 500, which is fixedly connected to the bearing 600, will also move upward accordingly. Of course, in other embodiments, the valve stem 300 may also have a drive protrusion on the periphery of its end. In this way, when the valve stem 300 moves axially upward, the drive protrusion abuts against the end face of the bearing 600, which can also drive the valve needle 500 to move upward.

[0058] Furthermore, please refer to the following: Figure 1 and Figure 2The valve needle 500 has a positioning step 330 at its end, and the drive collar 800 abuts against the positioning step 330. Thus, during the installation of the drive collar 800 onto the valve needle 500, the positioning step 330 serves a positioning function; when the end face of the drive collar 800 abuts against the positioning step 330, it indicates that the drive collar 800 is properly installed. Alternatively, in other embodiments, the positioning step 330 may be provided on the inner side of the drive collar 800; when the end of the valve stem 300 abuts against this positioning step 330, it indicates that the drive collar 800 is properly installed.

[0059] Furthermore, such as Figure 2 As shown, the drive collar 800 includes a second guide section 820 and a second connecting section 810 distributed axially. The valve stem 300 is interference-fitted with the second connecting section 810. The second guide section 820 is located on the side of the second connecting section 810 closer to the bearing 600, and the inner diameter of the second guide section 820 gradually increases from the end closer to the second connecting section 810 toward the end farther from the second connecting section 810. Thus, the second guide section 820 can guide the valve stem 300 and the drive collar 800 during assembly, making the insertion of the valve stem 300 into the drive collar 800 easier and faster.

[0060] Furthermore, such as Figure 2As shown, the drive collar 800 further includes a transition section 830 located on the side of the second connecting section 810 near the bearing 600, and the drive collar 800 has two second guide sections 820. The transition section 830 is connected to the end face of the drive collar 800 through one second guide section 820 and to the second connecting section 810 through the other second guide section 820. That is, between the end of the drive collar 800 near the bearing 600 and the end away from the bearing 600, the second guide section 820, the transition section 830, the second guide section 820, and the second connecting section 810 are connected in sequence, wherein the transition section 830 has a clearance fit with the valve stem 300. When assembling the drive collar 800, the valve stem 300 should be inserted from the end of the drive collar 800 closest to the bearing 600. This will allow the end of the valve stem 300 to first contact the position with the largest inner diameter of the second guide section 820 at that end of the drive collar 800, facilitating the alignment and insertion of the valve stem 300. Guided by the second guide section 820, the end of the valve stem 300 can be inserted into the transition section 830 with relatively little effort, and then through the transition section 830 to another second guide section 820. This second guide section 820 guides the valve stem 300 into the second connecting section 810. Since the second connecting section 810 has an interference fit with the valve stem 300, after the end of the valve stem 300 enters the second connecting section 810, it is necessary to increase the force to allow the valve stem 300 to continue inserting into the drive collar 800 until the drive collar 800 abuts against the positioning step 330. This allows for easier and faster assembly of the drive collar 800 and valve stem 300, which helps improve the production efficiency of electronic expansion valves.

[0061] Within the electronic expansion valve of the present invention, such as Figure 4As shown, a guide collar 400 is also installed inside the valve cavity 103. The guide collar 400 is located on the side of the nut 200 near the valve port 104. The valve needle 500 passes through the guide collar 400 and is inserted into the valve port 104. Driven by the valve stem 300, the valve needle 500 moves axially relative to the valve port 104 under the guidance of the guide collar 400, thereby opening or closing the valve port 104. It can be understood that the guide collar 400 and the valve port 104 are coaxially arranged. On the one hand, by restricting the valve needle 500 through the guide collar 400, the coaxiality between the valve needle 500 and the valve port 104 can be improved; on the other hand, when the valve stem 300 drives the valve needle 500 to move, the guide collar 400 can guide the axial movement of the valve needle 500 to ensure the smooth movement of the valve needle 500. In this way, the valve needle 500 can maintain a high degree of coaxiality with the valve port 104 in both static and dynamic states, which helps to ensure the accuracy of valve port 104 opening control and thus ensures the operational reliability of the electronic expansion valve. Furthermore, guided by the guide ring 400, the valve needle 500 will not undergo unnecessary movement relative to the valve port 104, thereby reducing wear between the valve needle 500 and the valve port 104, extending the service life of the valve needle assembly, and further ensuring the operational reliability of the electronic expansion valve.

[0062] Furthermore, in this embodiment, please also refer to... Figure 4 and Figure 9The valve needle 500 includes a needle body 510 and a connecting portion 520 connected to each other. The needle body 510 passes through the guide collar 400 and is inserted into the valve port 104. The connecting portion 520 has a portion located within the inner cavity of the nut 200. Specifically, the nut 200 has a first guide hole 212, and the connecting portion 520 is inserted into the first guide hole 212, having a portion located within the inner cavity of the nut 200. The nut 200 provides guidance for the axial movement of the connecting portion 520 through the first guide hole 212. The guide collar 400 has a second guide hole 401 for the needle body 510 to pass through, thereby guiding its axial movement. It is understood that both the first guide hole 212 and the second guide hole 401 are coaxial with the valve port 104. Due to the dual limiting and guiding functions of the first guide hole 212 of the nut 200 and the second guide hole 401 of the guide collar 400, the coaxiality of the valve needle 500 and the valve port 104 is high, which helps to ensure the accuracy of the valve port 104 opening control, thereby ensuring the working reliability of the electronic expansion valve. In particular, the depth of the second guide hole 401 is greater than or equal to 1 mm to meet the maximum axial movement of the needle body 510, so that the second guide hole 401 can provide guidance during the axial movement of the needle body 510. Alternatively, the needle body 510 and the connecting part 520 can be integrally formed to improve the production efficiency of the valve needle 500; or the needle body 510 and the connecting part 520 can be separately formed and then fixedly connected to simplify the mold structure and ensure the yield of finished products.

[0063] In some embodiments, such as Figure 9 As shown, the guide collar 400 also has a first clearance hole 402 that is axially distributed and connected to the second guide hole 401. One end of the connecting part 520 that is connected to the needle body 510 protrudes from the inner cavity of the nut 200 and is accommodated in the first clearance hole 402. Further, the guide collar 400 also has a second clearance hole 403, which is connected to the end of the first clearance hole 402 away from the second guide hole 401. The nut 200 is partially accommodated in the second clearance hole 403. It can be understood that the second guide hole 401 of the guide collar 400 needs to guide the valve needle 500, and the valve needle 500 is located close to the valve port 104. If the guide collar 400 is connected to the valve housing 100 through the outer wall of the second guide hole 401, it will easily affect the flow of refrigerant near the valve port 104. In this embodiment, a first clearance hole 402 of the clearance connection portion 520 and a second clearance hole 403 of the clearance nut 200 are sequentially provided on the side of the second guide hole 401 away from the valve port 104. Thus, the guide collar 400 is fixedly connected to the valve body 100 through the outer wall of the first clearance hole 402 or the outer wall of the second clearance hole 403, so that the connection structure between the guide collar 400 and the valve body 100 has an adverse effect on the flow of refrigerant.

[0064] In some embodiments, please refer to the following: Figure 4 , Figure 8 and Figure 9 As shown, the outer wall of the guide collar 400 is provided with a mounting step 410, and the inner wall of the valve body 100 is provided with a corresponding step space 110. The mounting step 410 engages with the step space 110. Specifically, the mounting step 410 is formed on the outer wall opposite to the first clearance hole 402 and the second clearance hole 403. The engagement of the mounting step 410 with the step space 110 allows the guide collar 400 to be fixedly installed on the valve body 100.

[0065] Furthermore, such as Figure 9 As shown, the stepped space 110 is formed by a first stepped surface 111 and a second stepped surface 112 connected together. The mounting step 410 includes a third stepped surface 411 abutting against the first stepped surface 111 and a fourth stepped surface 412 abutting against the second stepped surface 112. The first stepped surface 111 is arranged parallel to the axial direction of the guide collar 400. At least one of the end of the first stepped surface 111 away from the second stepped surface 112 and the end of the third stepped surface 411 near the fourth stepped surface 412 is provided with a guide structure to guide the mounting step 410 into the stepped space 110 when the guide collar 400 is assembled to the valve body 100.

[0066] Specifically, such as Figure 9 As shown, in this embodiment, a first guide surface 113 is provided on the side of the first step surface 111 away from the second step surface 112. The first guide surface 113 is gradually moved away from the third step surface 411 in a direction away from the first step surface 111. Further, two second guide surfaces 413 are provided at the end of the third step surface 411 near the fourth step surface 412. The second guide surfaces 413 are gradually moved closer to the first step surface 111 in a direction away from the fourth step surface 412. A transition surface 414 is provided between the two second guide surfaces 413. The transition surface 414 is parallel to the axial direction of the guide collar 400. The transition surface 414 is connected to the third step surface 411 through one of the second guide surfaces 413 and to the fourth step surface 412 through the other guide surface. To obtain the best guiding effect, the first guide surface 113 and the second guide surface 413 can be arranged in parallel, that is, parallel or approximately parallel.

[0067] During the assembly of the guide collar 400 into the valve body 100, the second guide surface 413, which is closer to the fourth step surface 412, first enters the space inside the first guide surface 113. Then, as the installation step 410 gradually engages with the step space 110, the transition surface 414, the other guide surface, and the third step surface 411 sequentially enter the space inside the first guide surface 113. In this process, at least one of the first guide surface 113 and the second guide surface 413 can guide the assembly until the third step surface 411 contacts the first step surface 111. Thus, through the stepped guide structure, the assembly of the guide collar 400 into the valve body 100 can be more labor-saving and faster, which is beneficial to improving the production efficiency of electronic expansion valves.

[0068] In some embodiments, please refer to the following: Figure 4 and Figure 9 The valve housing 100 has a refrigerant inlet 105 on its side wall, and the guide collar 400 has a flow-guiding cone surface 420 opposite to the refrigerant inlet 105. Thus, when the refrigerant flows between the refrigerant inlet 105 and the valve port 104, the flow-guiding cone surface 420 can guide the refrigerant flow, preventing turbulent flow and thus affecting the working performance of the electronic expansion valve.

[0069] In some embodiments, please refer to Figure 4 The valve chamber 103 includes a first valve chamber 1031 and a second valve chamber 1032 located on both axial sides of the guide collar 400. The guide collar 400 or the valve housing 100 is provided with a balancing channel for connecting the first valve chamber 1031 and the second valve chamber 1032. Due to the balancing channel, the air pressure in the first valve chamber 1031 and the second valve chamber 1032 can be balanced, which helps to ensure the stability of the internal pressure of the electronic expansion valve, reduces the operating resistance of the valve needle 500, and thus ensures the working performance of the electronic expansion valve.

[0070] Optionally, at least one of the first step surface 111 and the third step surface 411 is recessed with a first air passage groove, and at least one of the second step surface 112 and the fourth step surface 412 is recessed with a second air passage groove communicating with the first air passage groove, so as to form the balance channel in the first air passage groove and the second air passage groove. Without loss of generality, in one embodiment, the first step surface 111, the second step surface 112, the third step surface 411 and the fourth step surface 412 are all set as annular, so that the mounting step 410 and the step space 110 are both annular. The first step surface 111 and the third step surface 411 have both abutting portions and recessed portions forming the first air passage groove. Similarly, the second step surface 112 and the fourth step surface 412 have both abutting portions and recessed portions forming the second air passage groove. In this way, it can be ensured that the mounting step 410 is stably engaged in the step space 110, and a balance channel can be formed for the first valve chamber 1031 and the second valve chamber 1032 to communicate. In this embodiment, the first valve chamber 1031 is located on the side of the guide collar 400 away from the valve port 104. The two ends of the first air passage groove are respectively connected to one end of the first valve chamber 1031 and one end of the second air passage groove, and the other end of the second air passage groove is connected to the second valve chamber 1032. In this way, the first valve chamber 1031 and the second valve chamber 1032 can be connected, which is beneficial to ensure the stability of the internal pressure of the electronic expansion valve, thereby ensuring the working stability of the electronic expansion valve.

[0071] Optionally, such as Figure 9 As shown, the outer wall of the guide collar 400 is also provided with a connecting surface 430. The mounting step 410 is connected to the guide cone surface 420 through the connecting surface 430. The connecting surface 430 has an air passage 440 that penetrates the inner wall of the guide collar 400 to form the balance channel within the air passage 440. Specifically, there is a gap between the connecting surface 430 and the inner wall surface of the valve housing 100, and the connecting surface 430 is positioned relative to the first clearance hole 402. The air passage 440 penetrates from the connecting surface 430 to the inner wall surface of the first clearance hole 402. In this way, the first valve cavity 1031 can be connected to the first clearance hole 402 through the air passage 440. It can be understood that the first clearance hole 402 is for accommodating the connecting part 520, and there is a large gap between it and the connecting part 520. Similarly, the second clearance hole 403 is for accommodating the nut 200, and there is also a large gap between it and the nut 200. Therefore, the spaces within the first clearance hole 402 and the second clearance hole 403 both belong to the space of the second valve chamber 1032. The first valve chamber 1031 is connected to the first clearance hole 402, which is also connected to the second valve chamber 1032, thus ensuring the stability of the internal pressure of the electronic expansion valve and thereby ensuring the operational stability of the electronic expansion valve.

[0072] Furthermore, please refer to the following: Figures 4 to 7The needle body 510 and the guide collar 400, as well as the needle body 510 and the valve port 104, are all clearance fits. The connecting part 520 and the inner wall surface of the nut 200 are also clearance fits. The clearance between the connecting part 520 and the nut 200 is greater than the minimum clearance between the needle body 510 and the inner wall surface of the valve port 104, and the clearance between the needle body 510 and the guide collar 400 is also greater than the minimum clearance between the needle body 510 and the inner wall surface of the valve port 104.

[0073] Specifically, the clearance between the connecting part 520 and the nut 200 is the clearance between the outer wall surface of the connecting part 520 and the inner wall surface of the first guide hole 212 (i.e., Figure 7 (D3 in the text). The needle body 510 has a main body section 511 and a tip 512 distributed along the axial direction. The main body section 511 passes through the second guide hole 401 and is clearance-fitted with the second guide hole 401. The fit clearance between the needle body 510 and the guide collar 400 is the gap between the outer wall surface of the main body section 511 and the inner wall surface of the second guide (i.e., Figure 6 D2); the tip 512 is the first end 501 used for inserting into the valve port 104, and after the tip 512 is inserted into the valve port 104, it is in clearance fit with the inner wall surface of the valve port 104. The minimum fit clearance between the needle body 510 and the inner wall surface of the valve port 104 is the minimum fit clearance between the tip 512 and the inner wall surface of the valve port 104 (i.e., Figure 5 (D1 in the text). In addition, due to the existence of this minimum fit clearance, when the valve needle 500 closes the valve port 104, there is a certain gap between the outer wall surface of the tip 512 and the inner wall surface of the valve port 104, which can reduce the friction between the valve needle 500 and the valve port 104 and prevent the valve needle 500 from getting stuck.

[0074] In the electronic expansion valve of the present invention, when a foreign object is stuck between the valve port 104 and the valve needle 500, even if the tip 512 of the needle body 510 deflects, because the fitting clearance between the main body section 511 of the needle body 510 and the second guide hole 401 is greater than the minimum fitting clearance between the tip 512 and the inner wall surface of the valve port 104, there is sufficient room for movement between the main body section 511 and the inner wall surface of the second guide hole 401. Even if the main body section 511 is moved to tilt relative to the second guide hole 401, it will not jam with the second guide hole 401, but will still maintain a certain distance from the inner wall surface of the second guide hole 401. The gap will not affect the up-and-down movement of the needle body 510. Since the gap between the outer wall of the connecting part 520 and the inner wall of the nut 200 is greater than the minimum fitting gap between the tip 512 and the inner wall of the valve port 104, there is also sufficient room for movement between the connecting part 520 and the first guide hole 212 of the nut 200. Similarly, after the connecting part 520 is driven to tilt relative to the inner wall of the first guide hole 212, it will not be stuck with the first guide hole 212, but will still maintain a certain gap with the inner wall of the first guide hole 212. Thus, it will not affect the overall up-and-down movement of the valve needle 500. In summary, when a foreign object gets stuck between the tip 512 of the valve needle 500 and the valve port 104, the valve needle 500 can still move smoothly in the vertical direction because the main body section 511 of the valve needle 500 has sufficient deviation space in the inner cavity of the guide collar 400 and the connecting part 520 has sufficient deviation space in the inner cavity of the nut 200. This effectively prevents the valve needle 500 from getting stuck and also avoids the influence of eccentricity caused by coaxiality deviation during the assembly of the valve needle assembly on the valve needle 500.

[0075] Furthermore, in this embodiment, the clearance between the connecting part 520 and the nut 200 is greater than the clearance between the needle body 510 and the guide collar 400. That is, the clearance D3 between the outer wall surface of the connecting part 520 and the inner wall surface of the first guide hole 212 is greater than the clearance D2 between the outer wall surface of the main body section 511 and the inner wall surface of the second guide hole 401. It can be understood that when the valve port 104 is opened, the tip 512 of the needle body 510 disengages from the valve port 104. At this time, if a foreign object gets stuck in the gap between the main body section 511 and the second guide hole 401, even if the main body section 511 is tilted relative to the second guide hole 401, causing the connecting part 520 to tilt relative to the first guide hole 212, the connecting part 520 will not be stuck with the first guide hole 212, but will still maintain a certain clearance with the inner wall surface of the first guide hole 212. Thus, it will not affect the overall up and down movement of the valve needle 500.

[0076] Furthermore, in this embodiment, as Figure 4As shown, the nut 200 has a threaded hole 211 communicating with the first guide hole 212. The threaded hole 211 is located on the side of the first guide hole 212 away from the valve port 104. One end of the valve stem 300 is driven to be connected to the connecting part 520, and the other end of the valve stem 300 is threaded to the threaded hole 211. In this way, the coil drives the magnetic rotor 900 to rotate, and the magnetic rotor 900 drives the valve stem 300 to rotate. Through the threaded engagement with the nut 200, the valve stem 300 can simultaneously rotate circumferentially and move axially. The valve stem 300 then drives the valve needle 500 to move axially upward or downward, thereby controlling the flow rate of the electronic expansion valve. The clearance fit between the threaded section of the valve stem 300 and the threaded hole 211 allows the valve stem 300 to have a certain radial movement deviation relative to the nut 200. This allows the valve stem 300 and the nut 200 to further absorb concentric deviations, thereby improving the overall coaxiality.

[0077] In this embodiment, the clearance between the valve stem 300 and the threaded hole 211 is greater than the clearance between the connecting part 520 and the first guide hole 212 (i.e., D3). It can be understood that the valve stem 300 and the valve needle 500 are coaxially fitted. When the connecting part 520 is tilted relative to the first guide hole 212, since the minimum clearance between the valve stem 300 and the nut 200 occurs between the threaded section of the valve stem 300 and the threaded hole 211, and this clearance is greater than the clearance between the connecting part 520 and the first guide hole 212, there is sufficient room for movement between the valve stem 300 and the threaded section and the threaded hole 211. Even if the valve stem 300 is moved and tilts relative to the nut 200, the threaded section of the valve stem 300 will not jam with the threaded hole 211 of the nut 200, and will not affect the up-and-down movement of the valve needle assembly of the electronic expansion valve.

[0078] This invention also proposes a refrigeration device, which includes an electronic expansion valve. The specific structure of the electronic expansion valve is as described in the above embodiments. Since this refrigeration device adopts all the technical solutions of all the above embodiments, it possesses at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be elaborated further here. The refrigeration device can be an air conditioner, a freezer, a refrigerator, a heat pump water heater, etc.

[0079] The above description is merely an optional embodiment of the present invention and does not limit the patent scope of the present invention. All equivalent structural transformations made using the contents of the present invention's specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A valve needle assembly used in an electronic expansion valve, characterized in that, The valve needle assembly includes: A valve needle has a first end and a second end opposite to each other, the first end being detachably mounted to the valve port of the electronic expansion valve; A limiting collar is fixedly connected to the second end, and at least one of the second end and the limiting collar is provided with a mounting groove; The bearing is disposed in the mounting groove, and the two end faces of the outer ring of the bearing are respectively limited and abutted by the valve needle and the limiting collar to fix it in the mounting groove; The valve stem, passing through the limiting collar, is movably inserted into the inner ring of the bearing; and An elastic element is connected at one end to the valve stem and at the other end to the bearing. The elastic element is located on the side of the bearing opposite to the bottom of the mounting groove. The valve stem drives the valve needle to move axially through circumferential motion.

2. The valve needle assembly as claimed in claim 1, characterized in that, The second end is provided with the mounting groove, which has a first groove segment and a second groove segment distributed in the axial direction. The inner diameter of the first groove segment is larger than the inner diameter of the second groove segment. A limiting step is formed at the connection between the first groove segment and the second groove segment. The limiting step limits and abuts against the end face of the outer ring of the bearing near the first end.

3. The valve needle assembly as described in claim 2, characterized in that, The end face of the limiting collar near the first end is limited and abuts against the end face of the outer ring of the bearing away from the first end, and the limiting collar is fixedly connected to the groove wall of the mounting groove at the second end.

4. The valve needle assembly as claimed in claim 3, characterized in that, The limiting collar is inserted into the first groove section.

5. The valve needle assembly as claimed in claim 4, characterized in that, The limiting collar is connected to the groove wall of the first groove section by welding.

6. The valve needle assembly as claimed in claim 1, characterized in that, The valve needle assembly further includes a drive collar fixedly sleeved on the end of the valve needle, the drive collar being located on the side of the bearing closer to the first end.

7. The valve needle assembly as claimed in claim 6, characterized in that, The valve stem has a positioning step at its end, and the drive collar abuts against the positioning step.

8. The valve needle assembly as claimed in any one of claims 1 to 7, characterized in that, The valve needle includes a needle body and a connecting part connected together. The first end is located on the needle body and the second end is located on the connecting part. The needle body and the connecting part are integrally formed, or the needle body and the connecting part are separately formed and then fixedly connected. And / or, the elastic element is configured as a spring, and the peripheral wall of the valve stem is provided with a flange on the side of the bearing away from the first end, and the spring is sleeved on the valve stem and located between the flange and the end face of the bearing.

9. An electronic expansion valve, characterized in that, include: The nut has a mounting hole; The valve needle assembly as claimed in any one of claims 1 to 8, wherein the valve stem of the valve needle assembly passes through the mounting hole and is threadedly connected to the nut.

10. A refrigeration device, characterized in that, Includes the electronic expansion valve as described in claim 9.

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