Electronic expansion valve

Abstract

This is an electronic expansion valve (100). The electronic expansion valve (100) includes a spindle assembly (10) and a drive assembly (20), the spindle assembly (10) is reciprocated by the drive assembly (20) to control the flow rate of the electronic expansion valve (100), the spindle assembly (10) includes a spindle (11) and a pressure sleeve (12), the spindle (11) has a spindle chamber (111) formed inside it, and the pressure sleeve (12) is provided inside the spindle chamber (111) and A drive chamber (221) is fixed to the spindle (11), and a drive chamber (221) is formed between the drive assembly (20) and the spindle assembly (10). The pressure sleeve (12) is engageable with the drive assembly (20), and the spindle (11) and the pressure sleeve (12) define a connecting passage (13) between them, used to connect the drive chamber (221) and the spindle chamber (111), and to equalize the pressure between the drive chamber (221) and the spindle chamber (111).

Description

Technical Field

[0001] Related Applications This application claims the priority of a Chinese patent application with application number 202321148072.1 and title "Electronic Expansion Valve", which was filed on May 11, 2023, and the full text of which is incorporated herein by reference.

[0002] This application relates to the technical field of valves, and particularly to electronic expansion valves.

Background Art

[0003] Electronic expansion valves are widely applied in the air conditioning field and are used to adjust the flow rate of refrigerant. An electronic expansion valve includes a spindle assembly and a drive assembly. The spindle assembly is slidable relative to a guide sleeve under the action of the drive assembly. A spindle chamber is formed in the spindle assembly. The drive assembly can abut against the spindle assembly during the process of performing a reciprocating linear motion, whereby a closed space is formed in the spindle chamber and the pressure in the spindle chamber increases.

[0004] Currently, generally two types of modes are adopted for common electronic expansion valves. One is a mode in which the spindle assembly is not provided with an exhaust structure and cannot exhaust when the pressure in the spindle chamber increases. The other is a mode in which an exhaust structure is provided on the side surface of the spindle assembly, but exhaust is difficult due to interference from the guide sleeve during exhaust. Both of the two general modes result in an imbalance in the pressure difference between the inside and outside of the spindle chamber, increasing the torque force for downward movement after the drive assembly and the spindle assembly abut against each other, and affecting the operating stability of the drive assembly.

Summary of the Invention

[0005] According to various embodiments of this application, an electronic expansion valve is provided that can more easily control the stable movement of the drive assembly.

[0006] An electronic expansion valve comprising a spindle assembly and a drive assembly, wherein the spindle assembly is reciprocally movable by the drive assembly to control the flow rate of the electronic expansion valve, the spindle assembly comprising a spindle and a pressure sleeve, the spindle having a spindle chamber formed inside, the pressure sleeve being provided in the spindle chamber and fixed to the spindle, a drive chamber being formed between the drive assembly and the spindle assembly, and the pressure sleeve being engageable with the drive assembly, wherein the spindle and the pressure sleeve define a connecting passage between the spindle and the pressure sleeve, the connecting passage being formed to communicate the drive chamber and the spindle chamber and to equalize the pressure between the drive chamber and the spindle chamber.

[0007] In one embodiment, a first through-hole is drilled in the peripheral wall of the pressing sleeve and / or the chamber wall of the spindle chamber so as to form a connecting passage.

[0008] In one embodiment, the number of first through holes is one, or the number of first through holes is multiple, and the multiple first through holes are arranged at intervals along the circumferential direction of the pressing sleeve.

[0009] In one embodiment, the drive assembly includes a screw and a nut, the screw being screwed into the nut and engaged with the spindle assembly, and the drive chamber being formed inside the nut.

[0010] In one embodiment, a second through-hole is drilled in the nut, and the second through-hole communicates with the drive chamber.

[0011] In one embodiment, the pressing sleeve is housed inside the spindle chamber and is in close contact with the spindle.

[0012] In one embodiment, the pressing sleeve and the spindle are further welded together.

[0013] In one embodiment, the pressing sleeve has an inclined surface, and the screw has an arcuate surface, and the screw and the pressing sleeve can come into contact via the inclined surface and the arcuate surface so that the screw and the pressing sleeve make line contact.

[0014] In one embodiment, the electronic expansion valve further includes a pressing plate and an elastic member, both of which are provided within a spindle chamber, and the screw is capable of pressing the elastic member via the pressing plate such that the spindle moves away from the nut.

[0015] In one embodiment, the screw has a pressing surface, and the screw can contact a pressing plate via the pressing surface, where the pressing surface and the pressing plate are in point-to-surface contact.

[0016] In one embodiment, the pressing surface is provided as a spherical surface.

[0017] Details of one or more embodiments of this application are described in the following drawings and description. Other features, purposes and advantages of this application are evident from the specification, drawings and claims. [Brief explanation of the drawing]

[0018] One or more drawings can be referenced to better describe and illustrate the embodiments and / or examples of the inventions disclosed herein. Any additional details or examples provided in the drawings should not be considered to limit the scope of any of the disclosed inventions, the embodiments and / or examples described herein, or the best model of these inventions as understood herein.

[0019] [Figure 1] This is a cross-sectional view of an electronic expansion valve provided according to one embodiment of this application. [Figure 2] This is a cross-sectional view of a spindle assembly and screw provided according to one embodiment of this application. [Figure 3] This is an enlarged view of point P in Figure 2. [Figure 4] This is a schematic diagram of a pressing sleeve provided according to one embodiment of this application. [Figure 5] This is a perspective view of a pressing sleeve provided according to one embodiment of this application.

[0020] Explanation of the symbols 100 Electronic expansion valve, 10 Spindle assembly, 11 Spindle, 111 Spindle chamber, 12 Pressing sleeve, 121 First through hole, 122 Inclined surface, 13 Connecting passage, 14 Pressing plate, 15 Elastic member, 20 Drive assembly, 21 Screw, 211 Arc surface, 212 Pressing surface, 22 Nut, 221 Drive chamber, 222 Second through hole, 30 Guide sleeve, 31 Communication hole, 40 Valve body, 41 Valve chamber, 42 Valve port, 43 First connecting pipe, 44 Second connecting pipe, 45 Valve seat, 50 Rotor. [Modes for carrying out the invention]

[0021] To make the above-mentioned objectives, features, and advantages of this application clearer and easier to understand, specific embodiments of this application will be described in detail below with reference to the drawings. In the following description, various specific details will be explained in order to make this application easier to understand. However, this application can be carried out in many other forms different from those described herein, and those skilled in the art can make similar improvements as long as they do not contradict the content of this application, so this application is not limited by the specific embodiments disclosed below.

[0022] It should be noted that when an assembly is described as being "fixed" or "attached" to another assembly, it may be directly fixed to the other assembly, or there may be an intervening assembly. When an assembly is described as being "connected" to another assembly, it may be directly connected to the other assembly, or there may be an intervening assembly simultaneously. The terms “vertical,” “horizontal,” “up,” “down,” “left,” and “right” and similar expressions used in this specification are for illustrative purposes only and do not indicate that they represent only one embodiment.

[0023] Furthermore, the terms "first" and "second" are for illustrative purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the recited technical features. Thus, the features defined by "first" and "second" can explicitly include at least one of such features or implicitly include it. In the description of this application, "a plurality of" means at least two, for example, two, three, etc., unless there is a clear and specific limitation.

[0024] In this application, unless otherwise clearly defined and limited, when the first feature is "above", "below" the second feature, it may mean that the first feature and the second feature are in direct contact or the first feature and the second feature are indirectly in contact through an intermediate medium. Furthermore, when the first feature is "above", "above and "upper side" of the second feature, it may mean that the first feature is directly above or obliquely above the second feature, or simply that the horizontal height of the first feature is higher than that of the second feature. When the first feature is "below", "below" and "lower side" of the second feature, it may mean that the first feature is directly below or obliquely below the second feature, or simply that the horizontal height of the first feature is lower than that of the second feature.

[0025] Unless otherwise defined, all technical and scientific terms used in the specification of this application have the same meaning as commonly understood by those skilled in the art of this application. The terms used in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application. The term "and / or" used in the specification of this application includes any and all combinations of one or more of the related listed items.

[0026] Referring to FIGS. 1 and 2, an electronic expansion valve 100 provided by an embodiment of this application includes a spindle assembly 10 and a drive assembly 20. The drive assembly 20 is engaged with the spindle assembly 10 to reciprocate the spindle assembly 10, thereby controlling the flow rate of the electronic expansion valve 100.

[0027] The spindle assembly 10 includes a spindle 11 and a pressing sleeve 12. A needle-like structure is formed on one end of the spindle 11 away from the drive assembly 20, and a spindle chamber 111 is formed on the inside of the other end close to the drive assembly 20. The pressing sleeve 12 is provided inside the spindle chamber 111 and fixed to the spindle 11. A drive chamber 221 is formed between the drive assembly 20 and the spindle assembly 10, and the pressing sleeve 12 can engage with the drive assembly 20 to isolate the drive chamber 221 from the spindle chamber 111.

[0028] Here, the spindle 11 and the pressing sleeve 12 define a connecting passage 13 between them. The connecting passage 13 can connect the spindle chamber 111 and the drive chamber 221 to each other in order to equalize the pressure difference between the drive chamber 221 and the spindle chamber 111. In this way, when the drive assembly 20 drives the spindle 11 to reciprocate linear motion, the connecting passage 13 conducts between the drive chamber 221 and the spindle chamber 111, preventing the spindle chamber 111 from forming a sealed space during the process in which the pressing sleeve 12 and the drive assembly 20 engage and operate. This is advantageous for maintaining pressure equalization between the spindle chamber 111 and the drive chamber 221, and facilitates stable operation of the drive assembly 20 without encountering further resistance due to pressure imbalances inside and outside the spindle chamber 111 during the operation of the drive assembly 20.

[0029] As shown in Figures 4 and 5, in one embodiment, a first through-hole 121 is drilled in the peripheral wall of the pressing sleeve 12, and a connecting passage 13 is formed when the wall of the first through-hole 121 engages with the chamber wall of the spindle chamber 111, thereby realizing the installation of a connecting passage 13 between the spindle 11 and the pressing sleeve 12. The pressing sleeve 12 has a predetermined thickness to facilitate the machining of the first through-hole 121.

[0030] In this embodiment, there is one first through-hole 121, which is advantageous for improving processing efficiency. Of course, in other embodiments, there may be multiple first through-holes 121, and the multiple first through-holes 121 are arranged at intervals along the circumferential direction of the pressing sleeve 12 to improve the exhaust effect.

[0031] In another embodiment, the first through-hole 121 is provided in the chamber wall of the spindle chamber 111, and the hole wall of the first through-hole 121 engages with the peripheral wall of the pressing sleeve 12 to form a connecting passage 13, thereby realizing the installation of a connecting passage 13 between the spindle 11 and the pressing sleeve 12. The number of first through-holes 121 drilled in the chamber wall of the spindle chamber 111 may be one, two, three, etc., and is not limited thereto.

[0032] In yet another embodiment, first through-holes 121 are drilled in both the peripheral wall of the pressing sleeve 12 and the chamber wall of the spindle chamber 111. The walls of the first through-holes 121 in the pressing sleeve 12 and the walls of the first through-holes 121 in the spindle chamber 111 engage with each other to form a connecting passage 13, thereby realizing the installation of a connecting passage 13 between the spindle 11 and the pressing sleeve 12. The number of first through-holes 121 in the pressing sleeve 12 and the number of first through-holes 121 in the spindle chamber 111 are not limited.

[0033] Of course, the connection passage 13 between the spindle 11 and the pressing sleeve 12 may also be realized by engaging the wall of the first through hole 121 provided in the pressing sleeve 12 with the chamber wall of the spindle chamber 111, and engaging the wall of the first through hole 121 provided in the spindle chamber 111 with the peripheral wall of the pressing sleeve 12, and simultaneously combining them to form at least two connection passages 13.

[0034] In one embodiment, the pressing sleeve 12 is housed inside the spindle chamber 111 and in close contact with the spindle 11. Compared to a common configuration in which the pressing sleeve 12 protrudes from the edge of the chamber opening of the spindle chamber 111, this configuration has the effect of saving material for the pressing sleeve 12 and reducing costs.

[0035] In this embodiment, one end face of the pressing sleeve 12 that is close to the drive assembly 20 is flush with the edge of the chamber opening of the spindle chamber 111, thus saving material for the pressing sleeve 12. Of course, in other embodiments, one end face of the pressing sleeve 12 that is close to the drive assembly 20 may be positioned lower than the edge of the chamber opening of the spindle chamber 111.

[0036] In one embodiment, the pressing sleeve 12 and the spindle 11 may be fixed by welding. In other words, after the pressing sleeve 12 and the spindle 11 are brought into close contact, fixing them by welding increases the connection strength of the pressing sleeve 12 within the spindle chamber 111.

[0037] As shown in Figure 1, in one embodiment, the drive assembly 20 includes a screw 21 and a nut 22, the screw 21 having a male thread and the nut 22 having a female thread, and the screw 21 and nut 22 can be screwed together by fitting the nut 22 onto the screw 21. At the same time, the nut 22 is fixed in place so that the screw 21 can rotate in the circumferential direction and simultaneously reciprocate linearly along the axial direction of the screw 21 itself, thereby causing the spindle assembly 10 to reciprocate relative to the nut 22. The nut 22 has a drive chamber 221 formed inside it, a portion of the screw 21 is located inside the drive chamber 221 and inserted into the pressing sleeve 12, and one end of the screw 21 that is close to the spindle 11 abuts against the pressing sleeve 12, thereby restricting a portion of the screw 21 to the spindle 11.

[0038] In another embodiment, the nut 22 of the drive assembly 20 is provided but not fixed and connected to the spindle 11. The screw 21 and the nut 22 are screwed together, and the displacement of the screw 21 along its own axial direction is restricted so that the screw 21 rotates only in its circumferential direction, causing the nut 22 to reciprocate along the axial direction of the screw 21, thereby driving the spindle 11 to reciprocate up and down.

[0039] In one embodiment, the electronic expansion valve 100 further includes a pressure plate 14 and an elastic member 15, both of which are provided within the spindle chamber 111, and the pressure plate 14 is positioned between the screw 21 and the elastic member 15. One end face of the pressure plate 14 can contact the screw 21, and the other end face of the pressure plate 14 can contact the elastic member 15. When the screw 21 moves downward, the pressure plate 14 presses against the elastic member 15, causing the spindle 11 to move away from the nut 22. By providing the pressure plate 14, direct contact between the screw 21 and the elastic member 15 is avoided, and the pressure plate 14 is a smooth metal plate, reducing frictional resistance when the pressure plate 14 contacts the screw 21 and the elastic member 15. The elastic member 15 may specifically be provided as a return spring, which deforms under the action of an external force and returns to its original state after the external force is removed.

[0040] As shown in Figure 3, in one embodiment, the screw 21 is substantially straight, and a portion of it is located inside the spindle chamber 111. To allow the screw 21 to contact the pressing sleeve 12, the diameter of the portion of the screw 21 located inside the spindle chamber 111 gradually increases toward the spindle 11, forming an arcuate surface 211. The contact surface of the pressing sleeve 12 that contacts the screw 21 is provided as an inclined surface 122. The screw 21 and the pressing sleeve 12 engage via the arcuate surface 211 and the inclined surface 122 to form a line contact, reducing friction when the screw 21 and the pressing sleeve 12 come into contact.

[0041] In one embodiment, a pressing surface 212 is formed on one end of the screw 21 that is close to the spindle 11, and the screw 21 comes into contact with the pressing plate 14 via the pressing surface 212, thereby moving the spindle 11. The pressing surface 212 and the pressing plate 14 are in point-to-surface contact; in other words, a point on the pressing surface 212 is in contact with a plane on the pressing plate 14, resulting in a small contact area and a reduced frictional force between the screw 21 and the pressing plate 14, thereby reducing wear at the contact point between the screw 21 and the pressing plate 14.

[0042] As shown in Figure 2, furthermore, by providing the pressing surface 212 in a spherical shape, point-to-surface contact between the pressing surface 212 and the pressing plate 14 is realized. In this way, friction between the screw 21 and the pressing plate 14 is reduced, and at the same time, relative left-to-right movement becomes possible, thereby addressing the problem of poor coaxiality between the guide sleeve 30 and the valve seat 45. Of course, in other embodiments, the pressing surface 212 may be provided in an arc shape, a cone shape, or the like.

[0043] As shown in Figure 1, in one embodiment, a second through-hole 222 is drilled in the nut 22, and the drive chamber 221 communicates with the valve chamber 41 via the second through-hole 222, so that the pressure difference inside and outside the nut 22 can be easily equalized. The second through-hole 222 is located on one side of the nut 22 where the drive chamber 221 is drilled.

[0044] As shown in Figure 1, in one embodiment, the guide sleeve 30 is fixedly provided and connected to the nut 22, and the guide sleeve 30 is slidably engaged with the spindle 11 to guide the direction of movement of the spindle 11. Here, the guide sleeve 30 has a plurality of communication holes 31, and the spindle 11 is slidably relative to the guide sleeve 30 by the screw 21 and is engaged with the communication holes 31 to control the flow rate of the medium flowing through the communication holes 31.

[0045] As described above, when the electronic expansion valve 100 is activated, the coil (not shown) drives the rotor 50, which causes the screw 21 to rotate, and the screw 21, through screwing with the nut 22, converts the rotation into linear reciprocating motion along the axial direction of the screw 21 itself. When the screw 21 moves in a direction approaching the spindle 11, the pressure plate 14 is driven to compress the elastic member 15 so that the spindle 11 can move toward the valve opening 42 under the action of elastic force, and when the screw 21 moves in a direction away from the spindle 11, the elastic member 15 returns to its original position, causing the screw 21 to come into contact with the pressure sleeve 12 and the spindle 11 to move away from the valve opening 42. The medium flows from the first connecting pipe 43 into the valve body 40, flows through the communication hole 31 and the valve opening 42, and the spindle 11 can reciprocate up and down within the guide sleeve 30 to control the opening of the valve opening 42, thereby regulating the flow rate of the medium entering the valve body 40, and the medium flows out from the second connecting pipe 44. Alternatively, the medium may flow in from the second connecting pipe 44, flow through the valve opening and the communication hole 31, and flow out from the first connecting pipe 43.

[0046] The technical features of the above embodiments can be combined in any way, and for the sake of brevity, not all possible combinations of the technical features in the embodiments described above are described. However, as long as these combinations of technical features are inconsistent, they should all be considered to fall within the scope described herein.

[0047] The above embodiments merely illustrate some of the embodiments of this application, and although their descriptions are relatively specific and detailed, they should not be understood as limiting the scope of the claims of this application. It should be noted that those skilled in the art can make several modifications and improvements, provided they do not depart from the spirit of this application, and all of these fall within the scope of protection of this application. Therefore, the scope of protection of this patent application shall be in accordance with the attached claims.

Claims

1. Spindle assembly and Drive assembly and Equipped with, The spindle assembly is formed to be reciprocable by the drive assembly to control the flow rate of the electronic expansion valve, The spindle assembly includes a spindle and a pressing sleeve, A spindle chamber is formed inside the spindle, The pressing sleeve is provided within the spindle chamber and fixed to the spindle. A drive chamber is formed between the drive assembly and the spindle assembly. The pressing sleeve is engageable with the drive assembly, The spindle and the pressing sleeve define a connecting passage between the spindle and the pressing sleeve, and the connecting passage is formed to connect the drive chamber and the spindle chamber and to equalize the pressure between the drive chamber and the spindle chamber. Electronic expansion valve.

2. The peripheral wall of the pressing sleeve and / or the chamber wall of the spindle chamber are provided with a first through-hole to form the connecting passage. The electronic expansion valve according to claim 1.

3. The number of the first through-holes is one, or The number of the first through holes is multiple, and the multiple first through holes are arranged at intervals along the circumferential direction of the pressing sleeve. The electronic expansion valve according to claim 2.

4. The drive assembly includes a screw and a nut, The screw is screwed onto the nut and engaged with the spindle assembly, The drive chamber is formed inside the nut, The electronic expansion valve according to claim 1.

5. The nut has a second through-hole drilled in it. The second through-hole is in communication with the drive chamber. The electronic expansion valve according to claim 4.

6. The pressing sleeve is housed inside the spindle chamber and is in close contact with the spindle. The electronic expansion valve according to claim 1.

7. The pressing sleeve and the spindle are welded together. The electronic expansion valve according to claim 6.

8. The aforementioned pressing sleeve has an inclined surface, The screw has an arcuate surface formed on it. The screw and the pressing sleeve are capable of contacting each other via the inclined surface and the arcuate surface so as to bring the screw and the pressing sleeve into line contact. The electronic expansion valve according to claim 4.

9. Further comprising a pressing plate and an elastic member, Both the pressing plate and the elastic member are provided within the spindle chamber. The screw is capable of pressing the elastic member via the pressing plate so as to move the spindle away from the nut. The electronic expansion valve according to claim 4.

10. The screw has a pressing surface, The screw is capable of contacting the pressing plate via the pressing surface, The pressing surface and the pressing plate are in point-to-surface contact. The electronic expansion valve according to claim 9.

11. The pressing surface is provided as a spherical surface. The electronic expansion valve according to claim 10.

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