Valve needle assemblies, electronic expansion valves and refrigeration equipment

Abstract

A valve needle assembly, an electronic expansion valve and a refrigeration device are disclosed, the valve needle assembly includes a valve needle (500), a bearing (600) and a valve stem (300), the valve needle (300) includes an opposite first end (501) and a second end (502), the first end (501) is adapted to be detachably mounted to a valve port (104) of the electronic expansion valve, the bearing (600) is fixedly mounted to the second end (502) by an outer ring, and the valve stem (300) is inserted into an inner ring of the bearing (600). This technical solution aims to solve the technical problem in the prior art that the valve needle is easily worn due to the rotation of the valve needle relative to the valve port.

Description

[Technical field]

[0001] This application claims priority to a Chinese patent application filed on January 26, 2022, bearing application number 202210093235.4, the entire contents of which are incorporated herein by reference.

[0002] The present application relates to the technical field of electronic expansion valves, and in particular to a valve needle assembly, an electronic expansion valve, and a refrigeration device. [Background technology]

[0003] Conventional electronic expansion valves are based on the principle of a stepping motor, in which a magnetic rotor is rotated by a coil, the rotational motion of the magnetic rotor is converted into the axial motion of a valve stem, and a valve needle connected to the valve stem is raised and lowered by the valve stem to control the flow rate of the electronic expansion valve.

[0004] In the related art, the electronic expansion valve mainly includes a rotor, a valve stem, a nut and a valve needle, the valve stem is rotatably connected to the nut, the valve needle is provided at the lower end of the valve stem, the rotor moves the valve stem in the axial direction, and the valve needle moves in the axial direction to achieve the purpose of closing and opening the valve port. However, when using the above configuration, the valve needle rotates relative to the valve port when the valve port is closed and opened, and the valve needle and the valve port are worn, which shortens the service life of the valve needle.

[0005] The above contents are used to facilitate the understanding of the technical solutions of the invention, and are not admitted to be prior art. Summary of the Invention [Problem to be solved by the invention]

[0006] The main objective of the present application is to propose a valve needle assembly which aims to solve the technical problem of the prior art that the valve needle is prone to wear due to rotation of the valve needle relative to the valve orifice. [Means for solving the problem]

[0007] To achieve the above object, the present application proposes a valve needle assembly for use in an electronic expansion valve, the valve needle assembly including: a valve needle having opposite first and second ends, the first end being adapted for detachable mounting to a valve port of the electronic expansion valve; a bearing fixedly mounted to the second end by an outer ring; and a valve stem inserted into an inner ring of the bearing.

[0008] In one embodiment, the second end opens away from the first end, a mounting groove is formed in the valve needle, and the bearing is fixedly mounted in the mounting groove by an outer race. In one embodiment, the mounting groove has a relief space located on one side of the bearing close to the first end, the valve stem is inserted into the bearing, and an end of the valve stem protrudes into the relief space.

[0009] In one embodiment, the mounting groove 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 position limiting step is formed at the communicating portion between the first groove segment and the second groove segment, the bearing is mounted in the first groove segment, an end face of the outer ring of the bearing abuts against the position limiting step, and the relief space is located in the second groove segment.

[0010] In one embodiment, the valve needle assembly further includes a drive collar fitted to an end of the valve stem, the drive collar being located in the relief space and releasably abutting an end face of the bearing.

[0011] In one embodiment, the drive collar includes a guide segment and a connection segment distributed in the axial direction, the valve stem and the connection segment are tightly fitted, the guide segment is located on one side of the connection segment closer to the bearing, and the inner diameter of the guide segment gradually increases from the end closer to the connection segment to the end remote from the connection segment.

[0012] In one embodiment, the drive collar further includes a transition segment located on one side of the connection segment closer to the bearing, and the drive collar has two of the guide segments, the transition segment being connected to an end face of the drive collar via one of the guide segments and to the connection segment via the other of the guide segments.

[0013] In one embodiment, the distal end of the valve needle is provided with a locating step, the drive collar abutting against the locating step.

[0014] In one embodiment, the bearing is fixed in the mounting groove by press crimping.

[0015] In one embodiment, the groove wall of the first groove segment includes a main body portion and a press crimp portion connected to the groove wall of the second groove segment via the main body portion, and the groove wall of the press crimp portion has a thickness smaller than the groove wall thickness of the main body portion and is bent to abut against an end face of the outer ring of the bearing.

[0016] In one embodiment, the valve needle includes a needle body and a connecting portion which are interconnected, the first end being located in the needle body and the second end being located in the connecting portion, and the needle body and the connecting portion are integrally molded, or the needle body and the connecting portion are molded separately and then fixedly connected.

[0017] In one embodiment, the valve needle assembly further includes a resilient member, one end of the resilient member being connected to the valve stem and the other end being connected to the bearing, the valve stem being movably inserted into an inner ring of the bearing.

[0018] In one embodiment, the elastic member is provided as a spring fitted to the outside of the valve stem, and a flange portion is protrudingly provided on a peripheral wall of the valve stem on one side of the bearing remote from the first end, and the spring is located between the flange portion and an end face of the bearing.

[0019] The present application further proposes an electronic expansion valve, the electronic expansion valve comprising: A nut having a mounting hole; a valve needle assembly as described above, the valve stem being inserted into the mounting hole and threadably connected to the nut.

[0020] The present application further proposes a cooling device including the above-mentioned electronic expansion valve. Effect of the Invention

[0021] In the technical solution of the present application, the valve stem moves the valve needle in the axial direction and at the same time rotates in the circumferential direction. However, since the valve stem is inserted into the inner ring of the bearing and the outer ring of the bearing is fixedly connected to the valve needle, even if the inner ring of the bearing rotates together with the valve stem, the outer ring of the bearing fixedly connected to the valve needle can remain stationary in the circumferential direction, so the valve needle will not rotate in the circumferential direction. In the present application, the valve stem and the bearing are fitted together to cancel the circumferential movement transmitted from the valve stem to the valve needle, so that the valve needle only accepts the axial movement transmitted by the valve stem without rotating relative to the valve port, which is favorable to reducing the wear between the valve needle and the valve port, and ensures the operation reliability of the electronic expansion valve. In addition, the valve needle assembly of the present application has the advantages of having a very high reliability and a small number of parts, and has a small number of assembly steps in production and low manufacturing costs. [Brief description of the drawings]

[0022] In order to more clearly describe the technical solutions of the embodiments of the present application and the prior art, the following will briefly describe the accompanying drawings required for the description of the embodiments or the prior art. It is obvious that the accompanying drawings in the following description are only some of the embodiments of the present application, and those skilled in the art can obtain other accompanying drawings based on the structures shown in these accompanying drawings without creative work. [Figure 1] FIG. 2 is a structural schematic diagram of an embodiment of a valve needle assembly of the present application. [Diagram 2] FIG. 2 is a partially enlarged view of F in FIG. [Diagram 3] 1 is a structural schematic diagram of an embodiment of an electronic expansion valve of the present application; [Figure 4] FIG. 4 is a partially enlarged view of A in FIG. [Diagram 5] FIG. 4 is a partially enlarged view of B in FIG. [Figure 6] FIG. 4 is a partially enlarged view of C in FIG. [Figure 7] FIG. 4 is a partially enlarged view of D in FIG. [Figure 8] FIG. 4 is a partially enlarged view of E in FIG. 3. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] The realization of the object, the function features and advantages of the present invention will be further explained in combination with the embodiments with reference to the attached drawings.

[0024] The following will clearly and completely describe the technical solutions in the embodiments of the present application in combination with the drawings in the embodiments of the present application. It is clear that the described embodiments are not all the embodiments of the present application, but only some of the embodiments of the present application. Based on the embodiments of the present application, all other embodiments that a person skilled in the art can obtain without performing creative work fall within the scope of protection of the present application.

[0025] In addition, when the embodiments of the present application include directional indications (e.g., up, down, left, right, front, back, etc.), the directional indications are used only to explain the relative positional relationships, movement conditions, etc. between each part in a certain specific posture (see figure), and when the specific posture changes, the directional indications also change accordingly.

[0026] The terms "connected," "attached," "fixed," etc. should all be understood in a broad sense. For example, "connected" may mean a fixed connection, a detachable connection, or a connection as a whole, or may be directly interconnected, or indirectly interconnected through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the present application according to the specific situation.

[0027] In addition, when the description of "first", "second", etc. is concerned in the embodiments of the present application, the description of "first", "second", etc. is used for explanatory purposes only, and should not be understood as indicating or implying the relative importance thereof, or as implicitly specifying the number of technical features presented. Therefore, a feature limited to "first" or "second" may include at least one of the features, either explicitly or implicitly. In addition, "and / or" appearing in the whole sentence means including three parallel proposals. Taking "A and / or B" as an example, it includes proposal A, or proposal B, or a proposal in which A and B are simultaneously satisfied. In addition, the technical proposals of each embodiment can be combined with each other as long as they can be realized by a person skilled in the art. If a combination of technical proposals causes a contradiction or cannot be realized, it should be understood that such a combination of technical proposals does not exist and is not within the scope of the protection sought by the present application.

[0028] This application proposes an electronic expansion valve.

[0029] 3, the electronic expansion valve proposed by the present application includes a valve casing 100, a magnetic rotor 900, a nut 200, and a valve needle assembly. The valve casing 100 includes a housing 101 and a valve seat 102 fixedly connected to the housing 101, the housing 101 and the valve seat 102 surround a valve chamber 103, the magnetic rotor 900, the nut 200 and the valve needle assembly are all disposed in the valve chamber 103, the magnetic rotor 900 is rotatable relative to the valve casing 100, the nut 200 is fixedly connected to the valve seat 102, and the magnetic rotor 900 drives the movement of the valve needle assembly to control the flow rate of the electronic expansion valve.

[0030] The structure of the valve needle assembly is described below.

[0031] As shown in FIGS. 1 and 3 , the valve needle assembly includes a valve needle 500, a bearing 600, and a valve rod 300, where the valve needle 500 has an opposite first end 501 and a second end 502, the first end 501 is used for detachably mounting to the valve port 104 of the electronic expansion valve, the bearing 600 is fixedly mounted to the second end 502 by an outer ring, and the valve rod 300 is inserted into the inner ring of the bearing 600.

[0032] In the electronic expansion valve of the present application, the nut 200 is formed with a mounting hole 210 extending in its axial direction, the valve needle assembly is inserted into the mounting hole 210, and the valve rod 300 is screwed onto the nut 200. Specifically, a threaded rod segment is provided at one end of the valve rod 300 remote from the first open end, the mounting hole 210 includes a threaded hole segment matching the threaded rod segment, and the threaded rod segment is fitted into the threaded hole segment. The valve seat 102 is provided with a valve port 104 corresponding to the valve needle 500, and the valve needle 500 is detachably mounted in the valve port 104. In this way, the coil drives the magnetic rotor 900 to rotate, the magnetic rotor 900 rotates the valve stem 300, and through the engagement between the threaded rod segment and the threaded hole segment, the valve stem 300 can synchronously rotate in the circumferential direction and move axially, and the valve stem 300 further moves the valve needle 500 axially upward or downward, thereby controlling the flow rate of the electronic expansion valve.

[0033] In the valve needle assembly of the present application, the valve stem 300 moves the valve needle 500 axially and at the same time rotates in the circumferential direction. However, since the valve stem 300 is inserted into the inner ring of the bearing 600 and the outer ring of the bearing 600 is fixedly connected to the valve needle 500, even if the inner ring of the bearing 600 rotates together with the valve stem 300, the outer ring of the bearing 600 fixedly connected to the valve needle 500 can remain stationary in the circumferential direction, so that the valve needle 500 will not rotate in the circumferential direction. In the present application, the fitting of the valve stem 300 and the bearing 600 offsets the circumferential movement transmitted from the valve stem 300 to the valve needle 500, so that the valve needle 500 only accepts the axial movement transmitted by the valve stem 300 without rotating relative to the valve port 104, which is favorable to reduce the wear between the valve needle 500 and the valve port 104, and ensures the operation reliability of the electronic expansion valve. Additionally, the present valve needle assembly has the advantages of being extremely reliable while at the same time having a low part count, which reduces the number of assembly steps in production and reduces manufacturing costs.

[0034] 1, the valve needle assembly further includes an elastic member 310, one end of which is connected to the valve rod 300 and the other end of which is connected to the bearing 600, and the valve rod 300 is movably inserted into the inner ring of the bearing 600. Specifically, an end of the elastic member 310 is connected to an end face of the inner ring of the bearing 600, which is away from the first end 501, and the valve rod 300 drives the valve needle 500 to move axially through the elastic member 310, and the valve rod 300 is at least axially movable relative to the bearing 600. In this way, after the valve needle 500 abuts against the valve port 104, the valve rod 300 can continue to move downward relative to the valve needle 500 to compress the elastic member 310, so that the elastic member 310 can provide a provisional clamping force to the valve needle 500, so that the valve needle 500 can stably abut against the valve port 104. Of course, in other embodiments, the valve stem 300 may be fixedly inserted into the inner ring of the bearing 600 , so that the valve stem 300 can axially move the valve needle 500 through the bearing 600 .

[0035] In one embodiment, the end of the elastic member 310 and the end surface of the inner ring of the valve rod 300 and the bearing 600 are connected by abutment or fitting. It should be noted that the end of the elastic member 310 may directly abut the end surface of the inner ring of the valve rod 300 or the bearing 600, or may indirectly abut the end surface of the inner ring of the valve rod 300 or the bearing 600 through other parts. Without loss of generality, as shown in FIG. 1, in this embodiment, the elastic member 310 is provided as a spring. A flange portion 320 is provided on the peripheral wall of the valve rod 300. The spring is fitted on the valve rod 300, and one end abuts on the flange portion 320 and the other end abuts on the end surface of the inner ring of the bearing 600, thereby respectively realizing the connection with the end surfaces of the valve rod 300 and the bearing 600. Of course, in other embodiments, the elastic member 310 may be provided as an elastic piece, an elastic rubber sleeve, or an elastic silicone rubber sleeve.

[0036] 1 and 3, the second end 502 opens in a direction away from the first end 501, a mounting groove 530 is formed in the valve needle 500, and the bearing 600 is fixedly mounted in the mounting groove 530 by an outer ring. In this way, the bearing 600 is not exposed, and the fitting structure between the bearing 600 and the mounting groove 530 is also accommodated in the mounting groove 530, so that it is less susceptible to impact, which is advantageous for ensuring a stable connection between the bearing 600 and the mounting groove 530. Of course, in other embodiments, the end surface of the second end 502 may have a flat structure, and the bearing 600 may be fixedly mounted on the end surface of the second end 502. In this case, by leaving a gap between the inner ring of the bearing 600 and the end surface of the second end 502, it is possible to rotate the inner ring of the bearing 600 relative to the connecting part 520, and similarly, the circumferential rotation of the valve needle 500 can be avoided.

[0037] 1, the mounting groove 530 has an escape space 531 located on one side of the bearing 600 near the first end 501, and the valve rod 300 is inserted into the bearing 600 with its end protruding into the escape space 531. In this way, the end of the valve rod 300 can move toward the escape space 531 to compress the spring, thereby providing a pre-clamping force to the valve needle 500. Of course, in other embodiments, the axial length of the bearing 600 can be increased to provide sufficient space for the axial movement of the valve rod 300, in order to ensure that the spring can be compressed into a predetermined position to provide a sufficient pre-clamping force to the valve needle 500.

[0038] Furthermore, the mounting groove 530 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 position limiting step 532 is formed at the communication part between the first groove segment and the second groove segment, and the bearing 600 is mounted in the first groove segment. As shown in FIG. 1, the end face of the outer ring of the bearing 600 abuts against the position limiting step 532, and the relief space 531 is located in the second groove segment. Thus, when the bearing 600 is mounted in the mounting groove 530, the position limiting step 532 can function as a positioning step, and the bearing 600 abutting against the position limiting step 532 indicates that the bearing 600 is mounted in a predetermined position. In addition, since the position limiting step 532 only abuts against the end face of the outer ring of the bearing 600 and does not affect the circumferential rotation of the inner ring of the bearing 600, the inner and outer rings of the bearing 600 can rotate relative to each other. This ensures that the valve needle 500 can be stationary circumferentially relative to the valve port 104 when the valve stem 300 rotates circumferentially, thereby preventing excessive wear between the valve needle 500 and the valve port 104.

[0039] 1, the bearing 600 is fixed in the mounting groove 530 by a press crimping method. Specifically, the groove wall of the first groove segment includes a main body portion 533 and a press crimping portion 534 connected to the groove wall of the second groove segment via the main body portion 533. That is, when the press crimping portion 534 is an end of the groove wall of the first groove segment and the bearing 600 is mounted on the position limiting step 532, the outer ring of the bearing 600 abuts against the groove wall surface of the first groove segment, and the outer ring can be restricted in the circumferential direction of the bearing 600, so that the mounting stability of the bearing 600 is further improved. Then, if the press crimping portion 534 is bent to abut against the end surface of the outer ring of the bearing 600, the bearing 600 can be fixed in the mounting groove 530 by press crimping. Among these, the groove wall of the press crimping portion 534 is thicker than the groove wall of the main body portion 533, so that the force required to bend the press crimping portion 534 can be made smaller, and the press crimping process for the bearing 600 can be more easily and quickly achieved. As a result, the press crimping portion 534 and the position limiting step 532 limit the position of both axial sides of the bearing 600, and the groove wall of the first groove segment limits the bearing 600 in the circumferential direction, so that the bearing 600 can be stably and fixedly mounted in the mounting groove 530.

[0040] In some embodiments, as shown in FIG. 1, the valve needle assembly further includes a driving collar 800 fixedly fitted to the end of the valve needle 500, the driving collar 800 being located on one side of the bearing 600 close to the first end 501 and detachably abutting the end surface of the bearing 600. Thus, when the valve stem 300 moves axially upward, the position limiting collar is moved axially upward by the bearing 600 because it abuts the end surface of the bearing 600, and the bearing 600 also moves upward under the pressing force, and the valve needle 500 fixedly connected to the bearing 600 also moves upward. Of course, in other embodiments, a driving protrusion may be provided on the periphery of the end of the valve stem 300, so that when the valve stem 300 moves axially upward, the driving protrusion presses the end surface of the bearing 600, thereby similarly moving the valve needle 500 upward.

[0041] 1 and 2, the end of the valve needle 500 is provided with a positioning step 330, and the driving collar 800 abuts against the positioning step 330. In this way, in the process of mounting the driving collar 800 to the valve needle 500, the positioning step 330 can function as a positioning step, and the end face of the driving collar 800 abuts against the positioning step 330, which indicates that the driving collar 800 is mounted at a predetermined position. Of course, in other embodiments, a positioning step may be provided on the inside of the driving collar 800, and the end of the valve stem 300 abuts against the positioning step, which indicates that the driving collar 800 is mounted at a predetermined position.

[0042] 2, the drive collar 800 includes a guide segment 820 and a connection segment 810 distributed in the axial direction, the valve stem 300 and the connection segment 810 are tightly fitted, the guide segment 820 is located on one side of the connection segment 810 close to the bearing 600, and the inner diameter of the guide segment 820 gradually increases from the end close to the connection segment 810 to the end away from the connection segment 810. Thus, the guide segment 820 can function to guide the valve stem 300 and the drive collar 800 during the assembly process, so that the operation of inserting the valve stem 300 into the drive collar 800 is more labor-saving and quick.

[0043] 2, the drive collar 800 further includes a transition segment 830 located on one side of the connection segment 810 closer to the bearing 600, and the drive collar 800 has two guide segments 820, and the transition segment 830 is connected to the end face of the drive collar 800 through one of the guide segments 820 and connected to the connection segment 810 through the other guide segment 820. That is, the guide segment 820, the transition segment 830, the guide segment 820, and the connection segment 810 are connected in this order between the end of the drive collar 800 closer to the bearing 600 and the end of the drive collar 800 farther from the bearing 600, and the transition segment 830 is clearance-fitted to 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 closer to the bearing 600. Therefore, the end of the valve stem 300 first contacts the position of the largest inner diameter of the guide segment 820 at the end of the drive collar 800, which facilitates the alignment and engagement of the end of the valve stem 300. Guided by the guide segment 820, the end of the valve stem 300 can be inserted into the transition segment 830 with a relatively small force, and then through the transition segment 830 to the other guide segment 820 used to guide the insertion of the valve stem 300 into the connection segment 810. Because the connection segment 810 and the valve stem 300 are tightly fitted, only after the end of the valve stem 300 enters the connection segment 810 does the force need to be increased to continue inserting the valve stem 300 into the drive collar 800 until the drive collar 800 abuts against the positioning step 330. Thus, the assembly of the drive collar 800 and the valve stem 300 can be performed more labor-saving and quickly, which is favorable to improving the production efficiency of the electronic expansion valve.

[0044] As shown in FIG. 3, in the electronic expansion valve of the present application, a guide collar 400 is further installed in the valve chamber 103, the guide collar 400 is located on one side of the nut 200 close to the valve port 104, the valve needle 500 is inserted into the valve port 104 after passing through the guide collar 400, and the valve needle 500 is guided by the guide collar 400 to move axially relative to the valve port 104 by the driving of the valve stem 300, thereby opening and closing the valve port 104. The guide collar 400 and the valve port 104 are arranged coaxially. In one embodiment, the restriction of the guide collar 400 on the valve needle 500 can improve the coaxiality between the valve needle 500 and the valve port 104, while 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 stable movement of the valve needle 500. In this way, the valve needle 500 can maintain a high degree of concentricity with the valve port 104 whether in a stationary state or a moving state, which is beneficial to ensure the accuracy of the opening control of the valve port 104, and therefore the operational reliability of the electronic expansion valve can be ensured. In addition, the valve needle 500 is guided by the guide collar 400 and does not move unnecessarily relative to the valve port 104, which can reduce wear between the valve needle 500 and the valve port 104, which is beneficial to extend the service life of the valve needle assembly and further ensure the operational reliability of the electronic expansion valve.

[0045] 3 and 8, the valve needle 500 includes a needle body 510 and a connecting part 520 which are interconnected, the needle body 510 is inserted into the valve port 104 after passing through the guide collar 400, and the connecting part 520 has a part located in the internal space of the nut 200. Specifically, the nut 200 is provided with a first guide hole 212, the connecting part 520 is inserted into the first guide hole 212 and has a part located in the internal space of the nut 200, and the nut 200 guides the axial movement of the connecting part 520 through the first guide hole 212. The guide collar 400 is provided with a second guide hole 401, into which the needle body 510 is inserted to guide its axial movement. In addition, the first guide hole 212 and the second guide hole 401 are both coaxial with the valve port 104, and the double position restriction and guidance by the first guide hole 212 of the nut 200 and the second guide hole 401 of the guide collar 400 ensures high coaxiality between the valve needle 500 and the valve port 104, which is favorable for ensuring the accuracy of the opening control of the valve port 104 and can ensure the operation reliability of the electronic expansion valve. In particular, the depth of the second guide hole 401 is 1 mm or more so as to satisfy the maximum stroke of the axial movement of the needle body 510 and ensure that the second guide hole 401 can always guide the axial movement of the needle body 510. In addition, in one embodiment, the needle body 510 and the connecting part 520 are integrally molded, thereby improving the production and processing efficiency of the valve needle 500. Alternatively, the needle body 510 and the connecting portion 520 may be molded separately and then fixed and connected, thereby simplifying the structure of the mold and ensuring the product yield.

[0046] 8, the guide collar 400 is further provided with first relief holes 402 which are axially distributed and communicate with the second guide holes 401, and an end of the connection part 520 connected to the needle body 510 protrudes from the internal space of the nut 200 and is received in the first relief hole 402. In addition, the guide collar 400 is further provided with a second relief hole 403 which communicates with an end of the first relief hole 402 which is remote from the second guide hole 401, and the nut 200 is partially received in the second relief hole 403. The second guide hole 401 of the guide collar 400 needs to be fitted to guide the valve needle 500, but since the position of the valve needle 500 is close to the valve port 104, if the guide collar 400 is connected to the valve casing 100 via the outer wall of the second guide hole 401, it is likely to affect the flow of the refrigerant near the valve port 104. In this embodiment, a first relief hole 402 for releasing the connection part 520 and a second relief hole 403 for releasing the nut 200 are provided in this order on one side of the second guide hole 401 away from the valve port 104. As a result, if the guide collar 400 is fixedly connected to the valve casing 100 via the outer wall of the first relief hole 402 or the outer wall of the second relief hole 403, it is possible to avoid the adverse effect of the connection structure between the guide collar 400 and the valve casing 100 on the flow of the refrigerant.

[0047] 3, 7 and 8, in some embodiments, a mounting step 410 is protruded from the outer wall of the guide collar 400, and a stepped space 110 is correspondingly formed on the inner wall of the valve casing 100, and the mounting step 410 engages with the stepped space 110. Specifically, the mounting step 410 is formed on the outer walls facing the first relief hole 402 and the second relief hole 403, and the mounting step 410 engages with the stepped space 110, so that the guide collar 400 can be fixed and mounted to the valve casing 100.

[0048] 8, the step space 110 is formed by both the first step surface 111 and the second step surface 112 which are interconnected, the mounting step 410 includes a third step surface 411 which abuts against the first step surface 111 and a fourth step surface 412 which abuts against the second step surface 112, and the first step surface 111 is provided parallel to the axial direction of the guide collar 400. Among them, in order to guide the mounting step 410 to engage in the step space 110 when the guide collar 400 is fitted to the valve casing 100, at least one of an end of the first step surface 111 remote from the second step surface 112 and an end of the third step surface 411 close to the fourth step surface 412 is provided with a guide structure.

[0049] Specifically, in this embodiment, a first guide surface 113 is provided on one side of the first step surface 111 away from the second step surface 112, and the first guide surface 113 is provided so as to gradually move away from the third step surface 411 in a direction away from the first step surface 111. Furthermore, two second guide surfaces 413 are provided on one end of the third step surface 411 close to the fourth step surface 412, and the second guide surface 413 is provided so as to gradually move closer to the first step surface 111 in a direction away from the fourth step surface 412. A transition surface 414 parallel to the axial direction of the guide collar 400 is provided between the two second guide surfaces 413, and the transition surface 414 is connected to the third step surface 411 via one of the second guide surfaces 413 and connected to the fourth step surface 412 via the other guide surface. Here, in order to obtain an optimal guiding effect, the first guiding surface 113 and the second guiding surface 413 can be arranged in parallel, ie parallel or approximately parallel.

[0050] In the process of fitting the guide collar 400 to the valve casing 100, the second guide surface 413, which is closer to the fourth step surface 412, enters the inner space of the first guide surface 113 first, and then, as the mounting step 410 gradually engages in the step space 110, the transition surface 414, another guide surface, and the third step surface 411 enter the inner space of the first guide surface 113 in sequence. In this process, at least one of the first guide surface 113 and the second guide surface 413 can function to guide the fitting until the third step surface 411 contacts the first step surface 111. Thus, the stepped guide structure can make the process of fitting the guide collar 400 to the valve casing 100 more labor-saving and quick, which is favorable to improving the production efficiency of the electronic expansion valve.

[0051] 1 and 8, in some embodiments, a refrigerant passage port 105 is formed in the side wall of the valve casing 100, and the guide collar 400 is provided with a flow cone surface 420 facing the refrigerant passage port 105. Thus, when the refrigerant flows between the refrigerant passage port 105 and the valve port 104, the flow cone surface 420 can function to guide the flow of the refrigerant, so as to avoid disturbance of the flow of the refrigerant, which would affect the operating performance of the electronic expansion valve.

[0052] 1, in some embodiments, the valve chamber 103 includes a first valve chamber 1031 and a second valve chamber 1032 respectively located on both axial sides of the guide collar 400, and the guide collar 400 or the valve casing 100 is provided with a balance passage used to communicate the first valve chamber 1031 and the second valve chamber 1032. Since the balance passage is provided, the air pressures of the first valve chamber 1031 and the second valve chamber 1032 can be balanced, which is favorable to ensure the stability of the internal pressure of the electronic expansion valve, and the operating resistance of the valve needle 500 can be reduced, thereby ensuring the operating performance of the electronic expansion valve.

[0053] In one embodiment, a first ventilation groove is recessed in at least one of the first step surface 111 and the third step surface 411, and a second ventilation groove communicating with the first ventilation groove is recessed in at least one of the second step surface 112 and the fourth step surface 412, thereby forming the balance passage in the first ventilation groove and the second ventilation 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 provided in an annular shape, so that the mounting step 410 and the step space 110 are correspondingly annular. The first step surface 111 and the third step surface 411 have portions that abut against each other and have recessed portions in which the first ventilation groove is formed. Similarly, the second step surface 112 and the fourth step surface 412 have abutting portions and a recessed portion to form a second ventilation groove. In this way, it is possible to ensure that the mounting step 410 is stably engaged with the step space 110, and to form a balance passage that communicates between the first valve chamber 1031 and the second valve chamber 1032. In this embodiment, the first valve chamber 1031 is located on one side of the guide collar 400 away from the valve port 104, and both ends of the first ventilation groove communicate with the first valve chamber 1031 and one end of the second ventilation groove, respectively, and the other end of the second ventilation groove communicates with the second valve chamber 1032. In this way, the communication between the first valve chamber 1031 and the second valve chamber 1032 can be realized, which is favorable to ensure the stability of the internal pressure of the electronic expansion valve, and the operation stability of the electronic expansion valve can be ensured.

[0054] 1 and 8, in one embodiment, the outer wall of the guide collar 400 is further provided with a connection surface 430, the mounting step 410 is connected to the conical surface 420 through the connection surface 430, and the connection surface 430 is provided with a vent hole 440 penetrating the inner wall of the guide collar 400, so that the balance passage is formed in the vent hole 440. Specifically, there is a gap between the connection surface 430 and the inner wall surface of the valve casing 100, the connection surface 430 is provided opposite the first relief hole 402, and the vent hole 440 penetrates from the connection surface 430 to the inner wall surface of the first relief hole 402. Thus, the first valve chamber 1031 can communicate with the first relief hole 402 through the vent hole 440. In addition, the first relief hole 402 has a relatively large gap between it and the connecting part 520 to allow the connecting part 520 to escape, and the second relief hole 403 also has a relatively large gap between it and the nut 200 to allow the nut 200 to escape, so that both the space inside the first relief hole 402 and the space inside the second relief hole 403 belong to the space of the second valve chamber 1032. The first valve chamber 1031 communicates with the first relief hole 402, i.e., with the second valve chamber 1032, thereby ensuring the stability of the internal pressure of the electronic expansion valve and ensuring the operation stability of the electronic expansion valve.

[0055] 3 to 6, the engagement between the needle body 510 and the guide collar 400, and the engagement between the needle body 510 and the valve port 104 are both clearance fits, the connecting portion 520 is clearance fit into the inner wall surface of the nut 200, the engagement gap between the connecting portion 520 and the nut 200 is larger than the minimum engagement gap between the needle body 510 and the inner wall surface of the valve port 104, and the engagement gap between the needle body 510 and the guide collar 400 is larger than the minimum engagement gap between the needle body 510 and the inner wall surface of the valve port 104.

[0056] Specifically, the fitting gap between the connecting part 520 and the nut 200 is the gap between the outer wall surface of the connecting part 520 and the inner wall surface of the first guide hole 212 (i.e., D3 in FIG. 6). The needle body 510 has a body segment 511 and a tip 512 distributed in the axial direction, the body segment 511 is inserted into the second guide hole 401 and is clearance-fitted with the second guide hole 401, and the fitting gap between the needle body 510 and the guide collar 400 is the gap between the outer wall surface of the body segment 511 and the inner wall surface of the second guide hole (i.e., D2 in FIG. 5). The tip 512 is the first end 501 used to be inserted into the valve orifice 104, and when the tip 512 is inserted into the valve orifice 104, it is fitted into the inner wall surface of the valve orifice 104 with a clearance, and the minimum fitting gap between the needle body 510 and the inner wall surface of the valve orifice 104 is the minimum fitting gap between the tip 512 and the inner wall surface of the valve orifice 104 (i.e., D1 in FIG. 4). In addition, due to the presence of this minimum fitting gap, when the valve needle 500 closes the valve orifice 104, a certain gap is formed between the outer wall surface of the tip 512 and the inner wall surface of the valve orifice 104, which reduces the friction between the valve needle 500 and the valve orifice 104 and prevents the valve needle 500 from sticking.

[0057] According to the electronic expansion valve of the present invention, if a foreign object is caught between the valve port 104 and the valve needle 500, even if the tip 512 of the needle body 510 is tilted, the fitting gap between the body segment 511 of the needle body 510 and the inner wall surface of the second guide hole 401 is larger than the minimum fitting gap between the tip 512 and the inner wall surface of the valve port 104, so there is sufficient movement space between the body segment 511 and the inner wall surface of the second guide hole 401. Even if the body segment 511 is moved and tilted relative to the second guide hole 401, it will not stick to the second guide hole 401, but will maintain a certain gap with the inner wall surface of the second guide hole 401, so that the up and down movement of the needle body 510 will not be affected. In addition, because the gap between the outer wall surface of the connecting part 520 and the inner wall surface of the nut 200 is larger than the minimum fitting gap between the tip 512 and the inner wall surface of the valve port 104, there is also sufficient movement space between the connecting part 520 and the first guide hole 212 of the nut 200. Similarly, even if the connecting part 520 is moved and tilted relative to the inner wall surface of the first guide hole 212, it will not adhere to the first guide hole 212 but will maintain a constant gap with the inner wall surface of the first guide hole 212, so that the up and down movement of the entire valve needle 500 is similarly not affected. In short, even if a foreign object is caught between the tip 512 of the valve needle 500 and the valve port 104, there is sufficient space for displacement movement whether the main body segment 511 of the valve needle 500 is in the internal space of the guide collar 400 or the connecting part 520 is in the internal space of the nut 200, and the valve needle 500 can still move smoothly in the up and down direction, thereby effectively preventing the valve needle 500 from sticking and also preventing the impact of eccentricity of the valve needle 500 due to coaxiality deviation during assembly of the valve needle assembly.

[0058] Furthermore, in this embodiment, the fitting gap between the connection portion 520 and the nut 200 is larger than the fitting gap between the needle body 510 and the guide collar 400, that is, the gap D3 between the outer wall surface of the connection portion 520 and the inner wall surface of the first guide hole 212 is larger than the gap D2 between the outer wall surface of the body segment 511 and the inner wall surface of the second guide hole 401. Furthermore, when the valve port 104 is open, if the tip 512 of the needle body 510 moves away from the valve port 104 and a foreign object becomes caught in the gap between the body segment 511 and the second guide hole 401, even if the body segment 511 tilts relative to the second guide hole 401 and the connection part 520 is tilted relative to the first guide hole 212, the connection part 520 will not adhere to the first guide hole 212 and will maintain a certain gap with the inner wall surface of the first guide hole 212, so that the up and down movement of the entire valve needle 500 will not be affected.

[0059] In addition, in this embodiment, as shown in FIG. 1 , the mounting hole 210 further includes a threaded hole 211 located on one side of the first guide hole 212 away from the valve port 104, and one end of the valve rod 300 is drivingly connected to the connecting part 520 and the other end is screwed into the threaded hole 211, so that the coil drives the magnetic rotor 900 to rotate, and the magnetic rotor 900 rotates the valve rod 300, and through the engagement with the thread of the nut 200, the valve rod 300 can synchronously rotate in the circumferential direction and move in the axial direction, and the valve rod 300 further moves the valve needle 500 axially upward or downward, thereby controlling the flow rate of the electronic expansion valve. Meanwhile, since the screw segment of the valve stem 300 and the screw hole 211 are clearance-fitted, the valve stem 300 can have a certain radial movement deviation relative to the nut 200, so that the valve stem 300 and the nut 200 can further absorb the concentricity deviation and improve the overall concentricity.

[0060] In this embodiment, the fitting gap between the valve stem 300 and the threaded hole 211 is larger than the fitting gap (i.e., D3) between the connecting part 520 and the first guide hole 212. Note that the valve stem 300 is fitted coaxially with the valve needle 500, and when the connecting part 520 is tilted relative to the first guide hole 212, the minimum fitting gap between the valve stem 300 and the nut 200 is between the threaded segment of the valve stem 300 and the threaded hole 211, so this gap value is larger than the fitting gap between the connecting part 520 and the first guide hole 212. Thus, there is a sufficient movement space between the threaded segment of the valve stem 300 and the threaded hole 211, and even if the valve stem 300 is moved and tilted relative to the nut 200, the threaded segment of the valve stem 300 will not stick to 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.

[0061] This application also proposes a cooling device, which includes an electronic expansion valve, and the specific structure of the electronic expansion valve can be seen in the above embodiments. This cooling device adopts all the technical solutions of all the above embodiments, and at least has all the technical effects brought by the technical solutions of the above embodiments, so the description is omitted here. The cooling device can be an air conditioner, a freezer, a refrigerator, a heat pump water heater, etc.

[0062] The above is merely a preferred embodiment of the present application, and does not limit the scope of the patent of the present application. Any equivalent structural transformation made by utilizing the contents of the specification and accompanying drawings of the present application under the concept of the present application, or direct / indirect application to other related technical fields, is also included in the scope of protection of the patent of the present application. [Explanation of symbols]

[0063] 100 Valve casing 101 Housing 102 Valve seat 103 Valve chamber 1031 first valve chamber 1032 Second valve chamber 104 Valve Orifice 105 Refrigerant passage port 110 Step Space 111 First step surface 112 Second step surface 113 First guide surface 200 Nuts 210 Mounting hole 211 Screw hole 212 First guide hole 300 Valve stem 310 Elastic Members 320 Flange 330 Positioning step 600 Bearings 800 Drive Color 810 Connection Segments 820 Guidance Segment 830 Transition Segment 400 Guide Color 401 Second guide hole 402 First relief hole 403 Second relief hole 410 Installation step 411 Third step surface 412 Fourth step surface 413 Second guide surface 414 Transition Surface 420 Guide conical surface 430 Connection Surface 440 Vent 500 Valve Needle 501 first end 502 Second End 510 Needle body 511 Body Segment 512 Tip 520 Connection 530 Mounting groove 531 Relief space 532 Position restriction step 533 Main body 534 Press caulking part 900 Magnetic rotor

Claims

1. 1. A valve needle assembly for use in an electronic expansion valve, comprising: a valve needle having opposed first and second ends, the first end adapted to be releasably attached to a valve port of the electronic expansion valve; a bearing fixedly mounted to the second end by an outer ring; A valve stem inserted into the inner ring of the bearing; 2. A valve needle assembly comprising:

2. The second end opens away from the first end, a mounting groove is formed in the valve needle, and the bearing is fixedly mounted in the mounting groove by an outer ring.

2. The valve needle assembly of claim 1.

3. The mounting groove has a relief space located on one side of the bearing near the first end, the valve rod is inserted into the bearing, and an end of the valve rod is protruding into the relief space.

3. The valve needle assembly of claim 2.

4. The mounting groove 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 position limiting step is formed at a communicating portion between the first groove segment and the second groove segment, the bearing is mounted on the first groove segment, an end face of the outer ring of the bearing abuts against the position limiting step, and the relief space is located in the second groove segment.

4. The valve needle assembly of claim 3.

5. The valve needle assembly further includes a drive collar fitted to an end of the valve stem, the drive collar being located in the relief space and releasably abutting an end surface of the bearing.

4. The valve needle assembly of claim 3.

6. The drive collar includes a guide segment and a connection segment distributed in the axial direction, the valve stem and the connection segment are in an interference fit, the guide segment is located on one side of the connection segment closer to the bearing, and the inner diameter of the guide segment gradually increases from an end closer to the connection segment to an end remote from the connection segment.

6. The valve needle assembly of claim 5.

7. The drive collar further includes a transition segment located on one side of the connection segment closer to the bearing, the drive collar having two of the guide segments, the transition segment being connected to an end face of the drive collar via one of the guide segments and to the connection segment via the other of the guide segments.

7. The valve needle assembly of claim 6.

8. The valve needle has a positioning step at its distal end, and the drive collar abuts against the positioning step.

6. The valve needle assembly of claim 5.

9. The bearing is fixed in the mounting groove by press caulking.

5. The valve needle assembly of claim 4.

10. The groove wall of the first groove segment includes a main body portion and a press-fitted portion connected to the groove wall of the second groove segment via the main body portion, and the groove wall of the press-fitted portion has a thickness smaller than the thickness of the groove wall of the main body portion and is bent to abut against an end surface of the outer ring of the bearing.

10. The valve needle assembly of claim 9.

11. The valve needle includes a needle body and a connecting portion which are interconnected, the first end being located in the needle body and the second end being located in the connecting portion, and the needle body and the connecting portion are either integrally molded or the needle body and the connecting portion are molded separately and then fixedly connected.

2. The valve needle assembly of claim 1.

12. The valve needle assembly further includes an elastic member, one end of the elastic member being connected to the valve stem and the other end being connected to the bearing, the valve stem being movably inserted into an inner ring of the bearing. A valve needle assembly according to any one of claims 1 to 11.

13. The elastic member is provided as a spring fitted to the outside of the valve rod, and a flange portion is provided on the peripheral wall of the valve rod on one side of the bearing away from the first end, and the spring is located between the flange portion and the end face of the bearing.

13. The valve needle assembly of claim 12.

14. A nut having a mounting hole; A valve needle assembly according to any one of claims 1 to 13, wherein a valve stem is inserted into the mounting hole and threadably connected to the nut. Including an electronic expansion valve.

15. The electronic expansion valve according to claim 14 is included. cooling equipment.

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