CN112855953A

CN112855953A - Electronic expansion valve

Info

Publication number: CN112855953A
Application number: CN201911185382.9A
Authority: CN
Inventors: 曾庆军; 贺宇辰; 徐冠军
Original assignee: Zhejiang DunAn Hetian Metal Co Ltd
Current assignee: Zhejiang DunAn Hetian Metal Co Ltd
Priority date: 2019-11-27
Filing date: 2019-11-27
Publication date: 2021-05-28
Also published as: JP2023503404A; WO2021103753A1; JP7355937B2; KR20220092621A

Abstract

The invention provides an electronic expansion valve, comprising: a housing including a sleeve and a valve seat connected to each other, the valve seat having a first mounting hole; the screw rod is movably arranged in the shell; nut assembly, including nut seat and locating part, the screw rod is worn to establish in the nut seat, the nut seat includes screw thread section and the direction section that the ladder set up, the diameter of screw thread section is less than the diameter of direction section, the direction section is inserted and is established in first mounting hole, locating part and the up end looks laminating of direction section and with disk seat fixed connection, the locating part is used for going on spacing to the nut seat, be provided with limit structure between the lower terminal surface of direction section and the inner wall of disk seat, limit structure is used for spacing down to the nut seat. Through the technical scheme provided by the application, the problem that the coaxiality of the nut seat is poor in the prior art can be solved.

Description

Electronic expansion valve

Technical Field

The invention relates to the technical field of electronic expansion valves, in particular to an electronic expansion valve.

Background

At present, an electronic expansion valve includes a housing, a nut seat, a screw, and a valve needle, and the nut seat, the screw, and the valve needle are all disposed in the housing. Wherein, the casing includes disk seat and sleeve pipe, is provided with the valve port on the disk seat. Specifically, the nut seat is welded and fixed with the upper end face of the valve seat through the connecting sheet, the screw rod is movably arranged in the nut seat in a penetrating mode, the valve needle is arranged at one end, close to the valve port, of the screw rod, and the screw rod drives the valve needle to move so as to achieve opening and closing of the valve port.

However, in the prior art, the nut seat is located above the valve seat, and the nut seat is welded to the valve seat by the connecting sheet, and the nut seat moves under the action of stress generated by welding, so that the coaxiality of the nut seat and the valve seat cannot be ensured. Therefore, the problem that the coaxiality of the nut seat is poor exists in the prior art.

Disclosure of Invention

The invention provides an electronic expansion valve, which aims to solve the problem of poor coaxiality of a nut seat in the prior art.

The invention provides an electronic expansion valve, which comprises: a housing including a sleeve and a valve seat connected to each other, the valve seat having a first mounting hole; the screw rod is movably arranged in the shell; nut assembly, including nut seat and locating part, the screw rod is worn to establish in the nut seat, the nut seat includes screw thread section and the direction section that the ladder set up, the diameter of screw thread section is less than the diameter of direction section, the direction section is inserted and is established in first mounting hole, locating part and the up end looks laminating of direction section and with disk seat fixed connection, the locating part is used for going on spacing to the nut seat, be provided with limit structure between the lower terminal surface of direction section and the inner wall of disk seat, limit structure is used for spacing down to the nut seat.

Furthermore, a limiting convex part is arranged on the inner wall of the valve seat, the lower end face of the guide section is abutted against the limiting convex part, and the limiting convex part forms a limiting structure.

Further, first mounting hole has interconnect's first section and second section, and first section is located the top of second section, and the internal diameter of first section is greater than the internal diameter of second section, and the direction section is inserted and is established in first section, and the second section forms spacing convex part towards the terminal surface of first section.

Furthermore, a rotation stopping structure is arranged between the limiting part and the nut seat and used for limiting the nut seat to rotate relative to the valve seat.

Furthermore, the limiting part comprises a limiting ring, the nut seat further comprises a rotation stopping section, one end of the rotation stopping section is connected with the thread section, the other end of the rotation stopping section is connected with the guide section, the limiting ring is sleeved on the rotation stopping section, and the rotation stopping structure is arranged between the rotation stopping section and the limiting ring.

Furthermore, one of the rotation stopping section and the limiting ring is provided with a rotation stopping convex part, the other of the rotation stopping section and the limiting ring is provided with a rotation stopping groove, and the rotation stopping convex part and the rotation stopping groove are matched to form a rotation stopping structure.

Furthermore, a balance channel is arranged on the nut seat, the first mounting hole forms a valve cavity, the nut seat is provided with a nut cavity, one end of the balance channel is communicated with the valve cavity, and the other end of the balance channel is communicated with the nut cavity.

Furthermore, the balance channel comprises a first communicating section and a second communicating section which are communicated with each other, one end of the first communicating section is communicated with the nut cavity, one end of the second communicating section is communicated with the valve cavity, the first communicating section is arranged along the radial direction of the nut seat, and the second communicating section is arranged along the axial direction of the nut seat.

Furthermore, a first notch is formed in the outer wall of the rotation stopping section, a first communication hole is formed in the first notch, and the first notch and the first communication hole are matched to form a first communication section.

Furthermore, two rotation stopping convex parts are arranged on the rotation stopping section at intervals, the two rotation stopping convex parts are symmetrically arranged on two sides of the rotation stopping section, and the opening direction of the first through hole is perpendicular to the connecting line of the two rotation stopping convex parts.

Furthermore, the sleeve is provided with a sleeve cavity, a second notch is formed in the outer wall of the guide section, a second communication section is formed by the second notch, a second communication hole is formed in the limiting ring, and the second communication hole is communicated with the second notch so that the sleeve cavity is communicated with the valve cavity.

Further, be provided with a plurality of second breachs on the outer wall of direction section, a plurality of second breachs set up along the circumference symmetry of direction section, and at least one second breach is linked together with first communicating segment.

Further, the electronic expansion valve further comprises a valve seat core, a second mounting hole is formed in the valve seat, the valve seat core is arranged in the second mounting hole in a penetrating mode, the second mounting hole is a stepped hole, a stepped boss is arranged on the outer wall of the valve seat core, and the shape and the size of the stepped boss are matched with those of the stepped hole.

Furthermore, the guide section is of a cylindrical structure, a first installation boss is arranged in the guide section, the first installation boss and the nut seat are coaxially arranged, a second installation boss is arranged at the top of the valve seat core, the second installation boss and the valve seat core are coaxially arranged, the electronic expansion valve further comprises a guide sleeve, one end of the guide sleeve is sleeved on the first installation boss, and the other end of the guide sleeve is sleeved on the second installation boss.

Further, the nut seat further comprises a screw guiding section, the thread section, the rotation stopping section and the guiding section are sequentially connected from top to bottom, a first mounting boss coaxial with the nut seat is arranged in the guiding section, the nut seat is provided with a through hole along the axis direction, and the inner diameter of the screw guiding section, the inner diameter of the thread section, the inner diameter of the rotation stopping section and the inner diameter of the first mounting boss are sequentially reduced.

Further, the screw rod is movably worn to establish in the nut seat, screw rod and screw thread section screw-thread fit, and the screw rod direction section is used for leading the screw rod, and the inside undergauge of upper end of screw rod is formed with interior step, and electronic expansion valve still includes: the valve needle penetrates through the nut seat and the screw, the first mounting boss is provided with an inner hole for guiding the valve needle, and the screw applies downward driving force to the valve needle through the inner step; the positioning piece is fixedly arranged at the end part of the third section, and the screw rod applies upward driving force to the valve needle through the positioning piece; and the spring is sleeved on the third section and arranged between the fourth section and the inner step.

Further, the spring is indirectly abutted against the end face and/or the inner step of the fourth section through the washer.

By applying the technical scheme of the invention, the electronic expansion valve comprises a shell, a screw rod and a nut component, wherein the screw rod is movably arranged in the shell. The shell comprises a sleeve and a valve seat which are connected with each other, the valve seat is provided with a first mounting hole, the nut assembly comprises a nut seat and a limiting piece, and the screw rod penetrates through the nut seat. Specifically, the nut seat comprises a thread section and a guide section which are arranged in a stepped mode, and the diameter of the thread section is smaller than that of the guide section. Through inserting the direction section and establishing in first mounting hole, make the locating part laminate mutually with the up end of direction section and with disk seat fixed connection, can utilize the locating part to go up spacing to the nut seat, avoid the nut seat to deviate from in the disk seat. And, be provided with limit structure between the lower terminal surface of direction section and the inner wall of disk seat, utilize limit structure can carry out down spacing to the nut seat to fix the nut seat in the disk seat. Adopt above-mentioned structure, through inserting the direction section and establish in first mounting hole, can utilize the direction section to lead to the nut seat to guarantee the axiality of nut seat, then utilize locating part and limit structure to fix the nut seat, can accomplish the assembly of nut seat.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

fig. 1 is a sectional view of an electronic expansion valve according to an embodiment of the present invention;

FIG. 2 shows a partial enlarged view at A in FIG. 1;

FIG. 3 shows a partial enlarged view at B in FIG. 1;

FIG. 4 shows a schematic view of the nut socket of FIG. 1;

FIG. 5 shows a further schematic view of the nut seat of FIG. 1;

FIG. 6 shows an assembly view of the nut assembly of FIG. 1 with a valve seat;

FIG. 7 shows a cross-sectional view of the nut socket of FIG. 1;

fig. 8 is a sectional view of an electronic expansion valve according to a second embodiment of the present invention.

Wherein the figures include the following reference numerals:

10. a housing; 11. a sleeve; 111. a cannula lumen; 12. a valve seat; 121. a first mounting hole; 122. a limiting convex part; 123. a second mounting hole;

20. a screw; 201. an inner step;

30. a nut assembly; 31. a nut seat; 311. a threaded segment; 312. a guide section; 313. a rotation stopping section; 314. a first mounting boss; 315. a screw guide section; 32. a limiting member; 321. a second communication hole; 33. a balancing channel; 331. a first communication section; 3311. a first notch; 3312. a first communication hole; 332. a second communicating section; 3321. a second notch; 34. a nut cavity;

40. a rotation stopping structure; 41. a rotation stop protrusion; 42. a rotation stopping groove;

50. a valve seat core; 51. a second mounting boss;

60. a guide sleeve;

70. a valve needle; 71. a third stage; 72. a fourth stage;

80. a positioning member; 90. a spring;

100. a rotor assembly; 110. a rotor core; 120. a rotor connecting plate; 130. a fixing frame.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

As shown in fig. 1 to 7, an electronic expansion valve according to an embodiment of the present invention includes a housing 10, a screw 20, and a nut assembly 30, wherein the screw 20 and the nut assembly 30 are disposed in the housing 10, and the screw 20 is movable in the housing 10. The housing 10 includes a sleeve 11 and a valve seat 12 connected to each other, the valve seat 12 has a first mounting hole 121, the nut assembly 30 includes a nut seat 31 and a limiting member 32, the screw 20 is inserted into the nut seat 31, and one end of the nut seat 31 is inserted into the first mounting hole 121. Specifically, the nut seat 31 includes a threaded section 311 and a guiding section 312, the threaded section 311 has a smaller diameter than the guiding section 312, and the threaded section 311 is located above the guiding section 312. By inserting the guide section 312 into the first mounting hole 121, the nut holder 31 can be guided by the guide section 312 to ensure the coaxiality of the nut holder 31. In this embodiment, the guide section 312 is interference-fitted with the first mounting hole 121. After the guiding segment 312 is press-fitted into the first mounting hole 121, the limiting member 32 is attached to the upper end surface of the guiding segment 312 and is fixedly connected to the valve seat 12, so that the limiting member 32 can be used to limit the nut seat 31 upward, thereby preventing the nut seat 31 from coming out of the first mounting hole 121. In addition, a limiting structure is arranged between the lower end surface of the guide section 312 and the inner wall of the valve seat 12, and the nut seat 31 can be limited downwards by the limiting structure, so that the nut seat 31 is fixed, and the nut seat 31 is prevented from being excessively pressed into the first mounting hole 121.

By applying the electronic expansion valve provided by the embodiment, the guiding section 312 is matched with the first mounting hole 121, so that the nut seat 31 can be guided by the guiding section 312, and the coaxiality of the nut seat 31 can be ensured. In the assembly, the limiting structure can limit the nut seat 31 downwards, so that the nut seat 31 is prevented from being excessively inserted into the first mounting hole 121, when the nut seat 31 is assembled in place, the limiting part 32 is attached to the upper end face of the guide section 312, and the limiting part 32 is fixedly connected with the valve seat 12.

In the present embodiment, the limiting member 32 is fixedly connected to the valve seat 12 by welding, and since the guide section 312 of the nut seat 31 is press-fitted into the first mounting hole 121, the nut seat 31 does not move when the limiting member 32 is welded, so that the coaxiality of the nut seat 31 can be ensured. In the present embodiment, the upper end surface of the guide section 312 is flush with the upper end surface of the valve seat 12.

Wherein, the inner wall of the valve seat 12 is provided with a limit convex portion 122, the lower end surface of the guide section 312 is abutted against the limit convex portion 122, and the limit convex portion 122 forms a limit structure. Specifically, the limit protrusion 122 includes a limit step and a limit boss.

In this embodiment, the first mounting hole 121 has a first section and a second section connected to each other, the first section is located above the second section, the inner diameter of the first section is greater than that of the second section, and a limit step is formed at the connection of the first section and the second section. Specifically, the end surface of the second section facing the first section forms a limit protrusion 122. After the guiding section 312 is inserted into the first section, the end surface of the guiding section 312 abuts against the end surface of the second section facing the first section, so as to limit the nut seat 31. In other embodiments, a plurality of limiting bosses may be disposed on the inner wall of the valve seat 12, the limiting bosses are disposed at intervals along the circumferential direction of the valve seat 12, and the nut seat 31 is limited downward by the limiting bosses.

In the present embodiment, a rotation stopping structure 40 is disposed between the limiting member 32 and the nut seat 31, and the rotation stopping structure 40 is used for limiting the rotation of the nut seat 31 relative to the valve seat 12. The limiting member 32 and the nut seat 31 may be provided with a rotation stopping boss and a rotation stopping groove, and the rotation stopping boss and the rotation stopping groove may be used to cooperate to stop rotation, or the cross-sectional shapes of the limiting member 32 and the nut seat 31 may be set to be non-circular structures to stop rotation.

Specifically, the nut seat 31 further includes a rotation stopping section 313, one end of the rotation stopping section 313 is connected to the threaded section 311, and the other end of the rotation stopping section 313 is connected to the guiding section 312. In the present embodiment, the outer diameter of the rotation stop section 313 is larger than that of the threaded section 311, and the outer diameter of the rotation stop section 313 is smaller than that of the guide section 312. The limiting member 32 includes a limiting ring, the limiting ring is sleeved on the rotation stopping section 313, and the rotation stopping structure 40 is disposed between the rotation stopping section 313 and the limiting ring. Specifically, a rotation stopping boss or a rotation stopping groove may be provided on the rotation stopping section 313, or the cross-sectional shape of the rotation stopping section 313 may be a non-circular structure, and the structure and shape of the limit ring may be adapted to the rotation stopping section 313.

Wherein, one of the rotation stopping section 313 and the spacing ring is provided with a rotation stopping convex part 41, the other of the rotation stopping section 313 and the spacing ring is provided with a rotation stopping groove 42, and the rotation stopping convex part 41 and the rotation stopping groove 42 are matched to form the rotation stopping structure 40. In the embodiment, the rotation stopping section 313 is provided with a rotation stopping convex part 41, the limit ring is provided with a rotation stopping groove 42, and the rotation stopping convex part 41 extends along the radial direction of the rotation stopping section 313. In other embodiments, the rotation stopping section 313 may be configured as a rectangle, a triangle, etc., and the inner hole of the limiting ring is adapted to the cross-sectional shape of the rotation stopping section 313.

In order to facilitate the movement of the screw rod 20 in the nut seat 31, the nut seat 31 is provided with a balance passage 33, the first mounting hole 121 forms a valve cavity, the nut seat 31 is provided with a nut cavity 34, one end of the balance passage 33 is communicated with the valve cavity, and the other end of the balance passage 33 is communicated with the nut cavity 34. The nut chamber 34 and the valve chamber can be quickly pressure balanced by the balance passage 33, and the fluid in the nut chamber 34 does not obstruct the movement of the screw 20.

The balance passage 33 includes a first communicating section 331 and a second communicating section 332 which are communicated with each other, one end of the first communicating section 331 is communicated with the nut cavity 34, one end of the second communicating section 332 is communicated with the valve cavity, the first communicating section 331 is arranged along the radial direction of the nut seat 31, and the second communicating section 332 is arranged along the axial direction of the nut seat 31. With the above structure, the nut chamber 34 can be communicated with the valve chamber sequentially through the first communicating section 331 and the second communicating section 332.

Specifically, a first notch 3311 is disposed on an outer wall of the rotation stopping section 313, the first notch 3311 is disposed along a radial direction of the nut seat 31, a first through hole 3312 is disposed in the first notch 3311, and the first notch 3311 and the first through hole 3312 cooperate to form a first communicating section 331. Because the stop collar is sleeved on the rotation stopping section 313, the first notch 3311 is arranged on the outer wall of the rotation stopping section 313, so that a gap is formed between the stop collar and the outer wall of the rotation stopping section 313, and the first communicating section 331 is communicated with the second communicating section 332.

In the embodiment, the rotation stopping section 313 is provided with two rotation stopping protrusions 41 at intervals, the two rotation stopping protrusions 41 are symmetrically arranged at two sides of the rotation stopping section 313, and the opening direction of the first through hole 3312 is perpendicular to the connection line of the two rotation stopping protrusions 41, so that the mold opening is facilitated and the processing is facilitated.

Specifically, the sleeve 11 has a sleeve cavity 111, the outer wall of the guide section 312 is provided with a second notch 3321, the second notch 3321 forms a second communicating section 332, and the second communicating hole 321 is arranged on the limiting ring to communicate the second communicating hole 321 with the second notch 3321, so that the sleeve cavity 111 communicates with the valve cavity, and the pressure of the sleeve cavity 111 and the pressure of the valve cavity are rapidly balanced. In other embodiments, a communication groove may be provided on the inner wall of the valve seat 12, with which the second communication section 332 is formed.

In this embodiment, a plurality of second notches 3321 are disposed on the outer wall of the guide section 312, the plurality of second notches 3321 are symmetrically disposed along the circumferential direction of the guide section 312, and at least one second notch 3321 is communicated with the first communicating section 331. With the above structure, when the nut seat 31 is press-fitted into the first mounting hole 121, the plurality of second notches 3321 may play a role of assisting deformation, so as to facilitate press-fitting of the nut seat 31. Specifically, two second notches 3321 are provided on the outer wall of the guide section 312.

Specifically, the second notch 3321 is used to balance the pressures of the sleeve cavity 111 and the valve cavity, and to ensure the reliability of the nut seat 31. The nut seat 31 is in interference fit with the inner wall of the valve seat 12, the nut seat 31 needs to be pressed into the valve seat 12 during assembly, in order to prevent the nut seat 31 from being damaged, the second notch 3321 is equivalent to a contraction joint and allows certain deformation, and in order to ensure the deformation uniformity, the second notch 3321 needs to be symmetrically arranged to ensure the perpendicularity and the coaxiality of the nut seat 31.

The electronic expansion valve further includes a valve seat core 50, a second mounting hole 123 is formed in the bottom of the valve seat 12, and the valve seat core 50 is inserted into the second mounting hole 123. Specifically, the second mounting hole 123 is a stepped hole, a stepped boss is provided on the outer wall of the valve seat core 50, and the shape and size of the stepped boss are matched with the shape and size of the stepped hole, so that the coaxiality of the valve seat core 50 can be ensured. Wherein the valve port is provided on the valve seat core 50. In this embodiment, the first mounting hole 121 and the second mounting hole 123 are both machined by a lathe through one-time clamping, so that the coaxiality of the first mounting hole 121 and the second mounting hole 123 can be ensured, the nut seat 31 takes the first mounting hole 121 as a positioning reference, and the valve seat core 50 takes the second mounting hole 123 as a positioning reference, so that the coaxiality of the inner hole of the nut seat and the valve port of the valve seat core is ensured.

Specifically, the guide section 312 is a cylindrical structure, a first mounting boss 314 is disposed on a top surface of the guide section 312, the first mounting boss 314 is disposed coaxially with the nut seat 31, the first mounting boss 314 extends toward the valve seat core 50, a second mounting boss 51 is disposed on a top portion of the valve seat core 50, and the second mounting boss 51 is disposed coaxially with the valve seat core 50. In the present embodiment, the nut seat 31 is made of a plastic material.

In this embodiment, the nut seat 31 further includes a screw guiding section 315, and the screw guiding section 315, the threaded section 311, the rotation stopping section 313 and the guiding section 312 are sequentially connected from top to bottom. The guide section 312 is provided therein with a first mounting boss 314 coaxial with the nut seat 31, and the nut seat 31 has a through hole along the axial direction. Specifically, the inner diameter of the screw guide section 315, the inner diameter of the screw section 311, the inner diameter of the rotation stop section 313, and the inner diameter of the first mounting boss 314 are sequentially reduced. The screw guide section 315, the thread section 311 and the rotation stopping section 313 are located outside the valve seat 12, and only the guide section 312 is located inside the valve seat 12, so that the space of the electronic expansion valve can be fully utilized, the volume of the electronic expansion valve can be reduced, and the integration level can be improved.

In the present embodiment, the screw 20 is movably disposed in the nut seat 31, the screw 20 is threadedly engaged with the threaded section 311, and the screw 20 is rotatable relative to the nut seat 31. The screw guide section 315 is used for guiding the screw 20, and in the moving process of the screw 20, the screw guide section 315 can guide the screw 20, and an inner step 201 is formed in the upper end of the screw 20 in a diameter reducing manner.

In this embodiment, the electronic expansion valve further includes a valve needle 70, a positioning member 80, and a spring 90. Specifically, the valve needle 70 is arranged in the nut seat 31 and the screw rod 20 in a penetrating manner, the valve needle 70 is arranged corresponding to the valve port, the first mounting boss 314 has an inner hole for guiding the valve needle 70, and the screw rod 20 applies a downward driving force to the valve needle 70 through the inner step 201 to drive the valve needle 70 to move close to the valve port, so that the valve port is closed. Specifically, the valve needle 70 has a third section 71 and a fourth section 72 connected with each other, the diameter of the third section 71 is smaller than that of the fourth section 72, the third section 71 is located above the fourth section 72 and extends out of the upper portion of the screw 20, and the positioning member 80 is fixedly disposed at the end of the third section 71. By disposing the positioning member 80 at the end of the third section 71, the positioning member 80 can limit the position of the valve needle 70 relative to the screw 20, and the valve needle 70 can be prevented from falling off. In the present embodiment, the screw 20 applies an upward driving force to the valve needle 70 through the positioning member 80 to drive the valve needle 70 to move away from the valve port, so as to open the valve port. Specifically, the spring 90 is sleeved on the third section 71 and arranged between the fourth section 72 and the inner step 201, the spring 90 can provide a pretightening force, the precision of the device can be improved, and the spring 90 can also play a role in buffering.

Wherein the spring 90 indirectly abuts against the end surface of the fourth section 72 and/or the inner step 201 through a gasket, which is preferably made of a wear-resistant metal material, so as to prevent the metal spring 90 from wearing after contacting with the inner wall of the valve needle 70 or the screw 20, thereby increasing the product life. In this embodiment, washers are added to both ends of the spring 90, and the spring 90 indirectly abuts against the end surface of the fourth segment 72 and the inner step 201 through the washers.

In the present embodiment, the electronic expansion valve further includes a rotor assembly 100, the rotor assembly 100 is rotatably disposed in the housing 10, and the rotor assembly 100 is drivingly connected to the screw 20. The rotor assembly 100 includes, among other things, a rotor core 110 and a rotor connection plate 120.

In the present embodiment, both the sleeve 11 and the valve seat 12 are manufactured by a drawing process, and the amount of machining cut can be reduced and the efficiency can be improved by simply flattening the end surfaces.

Moreover, the electronic expansion valve further comprises a fixing frame 130, the fixing frame 130 is arranged on the outer wall of the valve seat 12, and the fixing frame 130 is of a fan-shaped structure, so that the material usage can be reduced to the greatest extent, and the cost can be reduced.

As shown in fig. 8, a second embodiment of the present invention provides an electronic expansion valve, which is different from the first embodiment in that in the second embodiment, the electronic expansion valve further includes a guide sleeve 60, one end of the guide sleeve 60 is sleeved on the first mounting boss 314 in an interference fit or transition fit manner, and the other end of the guide sleeve 60 is sleeved on the second mounting boss 51 in an interference fit manner, so that the nut seat 31 and the valve seat core 50 can be guided again by using the guide sleeve 60, and the coaxiality of the device can be further improved.

In this embodiment, the assembling steps of the electronic expansion valve are as follows:

(1) the valve seat 12 and the valve seat core 50 are fixed by furnace brazing;

(2) the guide sleeve 60 and the nut seat 31 are assembled together firstly and then pressed into the first mounting hole 121 of the valve seat 12 in an interference manner, so that the lower end surface of the nut seat 31 is abutted with the limit convex part 122;

(3) installing a limiting part 32 for laser welding fixation;

(4) the valve needle 70 and the spring 90 are sequentially placed in the screw rod, and then the screw rod 20 is screwed to the initial position;

(5) the rotor assembly 100 is put into the lower stop position and is screwed clockwise to be kept still, and the rotor connecting plate 120 and the screw 20 are fixed by laser welding;

(6) loading the positioning part 80, then rotating the rotor assembly 100 theta angle (the angle can be customized according to the adjustment characteristic, generally between 90 and 235 degrees) in the anticlockwise direction to keep the angle still, and performing laser welding fixing on the positioning part 80 and the valve needle 70;

(7) finally, the sleeve 11 is pressed in and welded, and then the sleeve is placed into the fixing frame 130 and welded, and the assembly is completed.

With the device provided in this embodiment, the nut seat 31 is provided as the guide section 312 having a skirt structure, and the guide section 312 is press-fitted into the valve seat 12, so that the coaxiality of the nut seat 31 and the valve seat 12 can be ensured, and the upper end surface and the lower end surface of the guide section 312 are respectively limited by the limiting member 32 and the limiting structure, thereby completing the assembly and fixation of the nut seat 31.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

The relative arrangement of the components and steps, the numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless specifically stated otherwise. Meanwhile, it should be understood that the sizes of the respective portions shown in the drawings are not drawn in an actual proportional relationship for the convenience of description. Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate. In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values. It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, further discussion thereof is not required in subsequent figures.

In the description of the present invention, it is to be understood that the orientation or positional relationship indicated by the orientation words such as "front, rear, upper, lower, left, right", "lateral, vertical, horizontal" and "top, bottom", etc. are usually based on the orientation or positional relationship shown in the drawings, and are only for convenience of description and simplicity of description, and in the case of not making a reverse description, these orientation words do not indicate and imply that the device or element being referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore, should not be considered as limiting the scope of the present invention; the terms "inner and outer" refer to the inner and outer relative to the profile of the respective component itself.

Spatially relative terms, such as "above … …," "above … …," "above … …," "above," and the like, may be used herein for ease of description to describe one device or feature's spatial relationship to another device or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if a device in the figures is turned over, devices described as "above" or "on" other devices or configurations would then be oriented "below" or "under" the other devices or configurations. Thus, the exemplary term "above … …" can include both an orientation of "above … …" and "below … …". The device may be otherwise variously oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

It should be noted that the terms "first", "second", and the like are used to define the components, and are only used for convenience of distinguishing the corresponding components, and the terms have no special meanings unless otherwise stated, and therefore, the scope of the present invention should not be construed as being limited.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An electronic expansion valve, comprising:

a housing (10) including a sleeve (11) and a valve seat (12) connected to each other, the valve seat (12) having a first mounting hole (121);

a screw (20) movably disposed within the housing (10);

nut assembly (30), including nut seat (31) and locating part (32), screw rod (20) are worn to establish in nut seat (31), nut seat (31) are including screw thread section (311) and the direction section (312) that the ladder set up, and the diameter of screw thread section (311) is less than the diameter of direction section (312), direction section (312) are inserted and are established in first mounting hole (121), locating part (32) with the up end facial features laminating of direction section (312) and with valve seat (12) fixed connection, locating part (32) are used for right nut seat (31) go up spacing, the lower terminal surface of direction section (312) with be provided with limit structure between the inner wall of valve seat (12), limit structure is used for right nut seat (31) go on down spacing.

2. An electronic expansion valve according to claim 1, wherein a limit protrusion (122) is arranged on the inner wall of the valve seat (12), the lower end surface of the guide section (312) abuts against the limit protrusion (122), and the limit protrusion (122) forms the limit structure.

3. An electronic expansion valve according to claim 2, wherein the first mounting hole (121) has a first section and a second section connected to each other, the first section is located above the second section, the first section has an inner diameter larger than that of the second section, the guide section (312) is inserted into the first section, and an end surface of the second section facing the first section forms the limit projection (122).

4. An electronic expansion valve according to claim 1, wherein a rotation stop structure (40) is arranged between the limiting member (32) and the nut seat (31), the rotation stop structure (40) being adapted to limit the rotation of the nut seat (31) relative to the valve seat (12).

5. The electronic expansion valve according to claim 4, wherein the limiting member (32) comprises a limiting ring, the nut seat (31) further comprises a rotation stopping section (313), one end of the rotation stopping section (313) is connected with the threaded section (311), the other end of the rotation stopping section (313) is connected with the guiding section (312), the limiting ring is sleeved on the rotation stopping section (313), and the rotation stopping structure (40) is arranged between the rotation stopping section (313) and the limiting ring.

6. An electronic expansion valve according to claim 5, wherein one of the rotation stop section (313) and the stop collar is provided with a rotation stop protrusion (41), the other of the rotation stop section (313) and the stop collar is provided with a rotation stop groove (42), and the rotation stop protrusion (41) and the rotation stop groove (42) cooperate to form the rotation stop structure (40).

7. An electronic expansion valve according to claim 5, wherein the nut seat (31) is provided with a balancing passage (33), the first mounting hole (121) forms a valve cavity, the nut seat (31) has a nut cavity (34), one end of the balancing passage (33) communicates with the valve cavity, and the other end of the balancing passage (33) communicates with the nut cavity (34).

8. An electronic expansion valve according to claim 7, wherein the equalization channel (33) comprises a first communication section (331) and a second communication section (332) communicating with each other, one end of the first communication section (331) communicating with the nut chamber (34), one end of the second communication section (332) communicating with the valve chamber, the first communication section (331) being arranged in a radial direction of the nut seat (31), and the second communication section (332) being arranged in an axial direction of the nut seat (31).

9. The electronic expansion valve according to claim 8, wherein a first notch (3311) is provided in an outer wall of the rotation stopping section (313), a first communicating hole (3312) is provided in the first notch (3311), and the first notch (3311) and the first communicating hole (3312) cooperate to form the first communicating section (331).

10. The electronic expansion valve according to claim 9, wherein two rotation-stopping protrusions (41) are spaced apart from each other on the rotation-stopping section (313), the two rotation-stopping protrusions (41) are symmetrically disposed on two sides of the rotation-stopping section (313), and an opening direction of the first through-hole (3312) is perpendicular to a line connecting the two rotation-stopping protrusions (41).

11. The electronic expansion valve according to claim 8, wherein the sleeve (11) has a sleeve chamber (111), the guide section (312) is provided with a second notch (3321) in the outer wall thereof, the second notch (3321) forms the second communicating section (332), the retainer ring is provided with a second communicating hole (321), and the second communicating hole (321) communicates with the second notch (3321) to communicate the sleeve chamber (111) with the valve chamber.

12. The electronic expansion valve according to claim 11, wherein the guide section (312) is provided with a plurality of second notches (3321) on an outer wall thereof, the plurality of second notches (3321) being symmetrically arranged along a circumferential direction of the guide section (312), at least one second notch (3321) being in communication with the first communication section (331).

13. The electronic expansion valve according to claim 1, further comprising a valve seat core (50), wherein a second mounting hole (123) is formed in the valve seat (12), the valve seat core (50) is inserted into the second mounting hole (123), the second mounting hole (123) is a stepped hole, a stepped boss is formed on an outer wall of the valve seat core (50), and the shape and size of the stepped boss are adapted to the shape and size of the stepped hole.

14. An electronic expansion valve according to claim 13, wherein the guide section (312) is a cylindrical structure, a first mounting boss (314) is provided in the guide section (312), the first mounting boss (314) is coaxially provided with the nut seat (31), a second mounting boss (51) is provided on the top of the valve seat core (50), the second mounting boss (51) is coaxially provided with the valve seat core (50), the electronic expansion valve further comprises a guide sleeve (60), one end of the guide sleeve (60) is sleeved on the first mounting boss (314), and the other end of the guide sleeve (60) is sleeved on the second mounting boss (51).

15. The electronic expansion valve according to claim 5, wherein the nut holder (31) further comprises a screw guide section (315), the threaded section (311), the rotation stopping section (313) and the guide section (312) are sequentially connected from top to bottom, a first mounting boss (314) coaxial with the nut holder (31) is provided in the guide section (312), the nut holder (31) has a through hole along an axial direction, and an inner diameter of the screw guide section (315), an inner diameter of the threaded section (311), an inner diameter of the rotation stopping section (313) and an inner diameter of the first mounting boss (314) are sequentially reduced.

16. The electronic expansion valve according to claim 15, wherein the screw rod (20) is movably disposed in the nut seat (31), the screw rod (20) is in threaded engagement with the threaded section (311), the screw rod guide section (315) is used for guiding the screw rod (20), an inner step (201) is formed by reducing the inner diameter of the upper end of the screw rod (20), and the electronic expansion valve further comprises:

a valve needle (70), wherein the valve needle (70) is arranged in the nut seat (31) and the screw rod (20) in a penetrating way, the first mounting boss (314) is provided with an inner hole for guiding the valve needle (70), and the screw rod (20) applies downward driving force to the valve needle (70) through the inner step (201);

the valve needle (70) is provided with a third section (71) and a fourth section (72) which are connected with each other, the diameter of the third section (71) is smaller than that of the fourth section (72), the third section (71) is positioned above the fourth section (72) and extends out of the upper part of the screw rod (20), the positioning part (80) is fixedly arranged at the end part of the third section (71), and the screw rod (20) applies upward driving force to the valve needle (70) through the positioning part (80);

and the spring (90) is sleeved on the third section (71) and arranged between the fourth section (72) and the inner step (201).

17. An electronic expansion valve according to claim 16, wherein the spring (90) indirectly abuts against the end surface of the fourth section (72) and/or the inner step (201) via a washer.