CN112984127A

CN112984127A - Electronic expansion valve

Info

Publication number: CN112984127A
Application number: CN202011459917.XA
Authority: CN
Inventors: 不公告发明人
Original assignee: Zhejiang Sanhua Automotive Components Co Ltd
Current assignee: Zhejiang Sanhua Automotive Components Co Ltd
Priority date: 2019-12-12
Filing date: 2020-12-11
Publication date: 2021-06-18

Abstract

An electronic expansion valve comprises a valve component, wherein the valve component comprises a rotor assembly, a sleeve, a connecting piece, a first bearing piece and a second bearing piece, the rotor assembly comprises a support, the support comprises a first concave cavity and a second concave cavity, the sleeve is positioned on the periphery of the rotor assembly, the sleeve comprises an assembly cavity, the first bearing piece is positioned in the assembly cavity and fixedly connected with the sleeve, part of the first bearing piece is positioned in the first concave cavity, the second bearing piece is fixedly connected with the connecting piece, part of the second bearing piece is positioned in the second concave cavity, and the rotor assembly is axially limited through the first bearing piece and the second bearing piece; meanwhile, a part of the first bearing piece is arranged in the first sunken cavity, and a part of the second bearing piece is arranged in the second sunken cavity, so that the size of the electronic expansion valve is further reduced.

Description

Electronic expansion valve

[ technical field ] A method for producing a semiconductor device

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

[ background of the invention ]

In an automobile air conditioning system, in order to improve the flow control precision of a working medium, an electronic expansion valve is often adopted as a throttling element, and the conventional electronic expansion valve drives a valve core to reciprocate up and down through the circumferential and axial movement of a rotor assembly, so that the stroke space of the axial movement of the rotor assembly is involved, and the volume of the electronic expansion valve is relatively large.

[ summary of the invention ]

The invention aims to provide an electronic expansion valve which is beneficial to reducing the volume of the electronic expansion valve.

In order to achieve the purpose, the invention adopts the following technical scheme: an electronic expansion valve, includes control division, stator module, valve member and valve body, the control division with stator module is connected, the valve member with the valve body is connected, stator module is located the periphery of valve member, stator module with the valve body is connected, its characterized in that: the valve part comprises a rotor assembly, a sleeve, a connecting piece, a first bearing piece and a second bearing piece, the rotor assembly comprises a support, the support comprises a first concave cavity and a second concave cavity, the sleeve is located at the periphery of the rotor assembly, the sleeve is fixedly connected with the connecting piece, the connecting piece is fixedly connected with the valve body, the sleeve comprises an assembly cavity, the first bearing piece is located in the assembly cavity and fixedly connected with the sleeve, part of the first bearing piece is located in the first concave cavity, the second bearing piece is fixedly connected with the connecting piece, part of the second bearing piece is located in the second concave cavity, and the rotor assembly is axially limited through the first bearing piece and the second bearing piece.

The invention provides an electronic expansion valve, which comprises a valve component, wherein the valve component comprises a rotor assembly, a sleeve, a connecting piece, a first bearing piece and a second bearing piece, the rotor assembly comprises a support, the support comprises a first concave cavity and a second concave cavity, the sleeve is positioned on the periphery of the rotor assembly, the sleeve comprises an assembly cavity, the first bearing piece is positioned in the assembly cavity and fixedly connected with the sleeve, part of the first bearing piece is positioned in the first concave cavity, the second bearing piece is fixedly connected with the connecting piece, part of the second bearing piece is positioned in the second concave cavity, and the rotor assembly is axially limited through the first bearing piece and the second bearing piece; meanwhile, a part of the first bearing piece is arranged in the first sunken cavity, and a part of the second bearing piece is arranged in the second sunken cavity, so that the size of the electronic expansion valve is further reduced.

[ description of the drawings ]

FIG. 1 is a schematic cross-sectional view of one embodiment of an electronic expansion valve;

FIG. 2 is a schematic cross-sectional view of the valve member of FIG. 1;

FIG. 3 is a perspective view of the rotor assembly of FIG. 2;

FIG. 4 is a cross-sectional structural view of the stent of FIG. 3;

FIG. 5 is a perspective view of the valve spool assembly of FIG. 2;

FIG. 6 is a cross-sectional structural view of the valve spool assembly of FIG. 2;

FIG. 7 is a perspective view of the connecting member and valve seat of FIG. 2;

FIG. 8 is a cross-sectional structural view of the attachment member and valve seat of FIG. 2;

FIG. 9 is a cross-sectional structural view of the valve body of FIG. 1;

fig. 10 is a schematic cross-sectional view of a second embodiment of an electronic expansion valve;

FIG. 11 is a cross-sectional structural view of the valve member of FIG. 10;

FIG. 12 is a cross-sectional view of the connector of FIG. 11;

FIG. 13 is a cross-sectional structural view of the valve body of FIG. 10;

fig. 14 is a schematic cross-sectional view of a third embodiment of an electronic expansion valve;

fig. 15 is a schematic cross-sectional view of a fourth embodiment of an electronic expansion valve.

[ detailed description ] embodiments

The invention will be further described with reference to the following figures and specific examples:

referring to fig. 1, the electronic expansion valve 100 may be applied to an automotive air conditioning system, the electronic expansion valve 100 includes a control part 1, a stator assembly 2, a valve member 3 and a valve body 4, the control part 1 is connected with the stator assembly 2, the valve member 3 is connected with the valve body 4, the stator assembly 2 is located at the periphery of part of the valve member 3, the stator assembly 2 is connected with the valve body 4, and the electronic expansion valve 100 is electrically connected and/or signal-connected with the outside through the control part 1.

Referring to fig. 1, the control portion 1 includes a circuit board 11, an outer casing 12 and a cover plate 13, the outer casing 12 and the cover plate 13 are respectively injection molded and fixedly connected, the outer casing 12 has a control cavity 121, and the circuit board 11 is located in the control cavity 121; the control part 1 further comprises an interface part 14, the interface part 14 and the outer shell 12 are integrally formed by injection molding, the interface part 14 comprises a first pin 141, the interface part 14 is provided with a first accommodating cavity 142, the middle part of the first pin 141 is fixed with the outer shell 12 by injection molding, and one end of the first pin 141 is located in the first accommodating cavity 142 and is electrically and/or signal-connected with the outside; the other end of the first pin 141 is located in the control cavity 121 and is electrically and/or signal connected to the circuit board 11.

Referring to fig. 1, the stator assembly 2 includes a cover 21, a coil winding 22 and a second pin 23, the cover 21 is formed by integrally injection molding using the coil winding 22 and the second pin 23 as injection inserts, the cover 21 and the outer housing 12 are integrally injection molded, and one end of the second pin 23 is located in the cover 21 and electrically connected and/or signal-connected with the coil winding 22; the other end of the second pin 23 is located in the control cavity 121 and electrically and/or signal connected to the circuit board 11. The stator assembly 2 is provided with a second accommodating cavity which is communicated with the control cavity 121, the stator assembly 2 is positioned on the radial periphery of the valve part 3 through the second accommodating cavity, part of the valve part 3 is positioned in the second accommodating cavity, and part of the valve part 3 is positioned in the control cavity 121; further, a sealing arrangement may be provided between the stator assembly 2 and the valve member 3, which is beneficial to reduce the risk of the circuit board 11 and/or the coil winding 22 failing or corroding due to the contact between the external environment moisture and the circuit board 11 and/or the coil winding 22.

Referring to fig. 2, the valve member 3 includes a rotor assembly 31, a connecting member 32, a valve seat 33, a valve core assembly 34, a sleeve 35 and a screw rod 36, the connecting member 32 is fixed to the valve seat 33 in an interference fit manner, and as another embodiment, the connecting member 32 and the valve seat 33 may also be integrally formed; referring to fig. 2 and 3, the rotor assembly 31 includes a permanent magnet 311 and a bracket 312, the permanent magnet 311 is located at the periphery of the bracket 312, the permanent magnet 311 is fixedly connected with the bracket 312, specifically, the bracket 312 may be integrally injection molded, and then the bracket 312 is used as an injection insert to injection mold the permanent magnet 311, that is, the permanent magnet 311 and the bracket 312 are injection molded and fixed; referring to fig. 4, the bracket 312 includes a first through hole 3121, a first recessed cavity 3122, and a second recessed cavity 3123, the first through hole 3121 is disposed in communication with the first recessed cavity 3122, and the first through hole 3121 is disposed in communication with the second recessed cavity 3123; referring to fig. 2, the lead screw 36 passes through the first through hole 3121, and a part of the rod body of the lead screw 36 is in interference fit with the first through hole 3121, so as to ensure the fixed connection of the lead screw 36 and the rotor assembly 31; referring to fig. 5, the valve core assembly 34 includes a valve core 341 and a nut 342, in this embodiment, the valve core assembly 34 further includes a connecting ring 343, the connecting ring 343 is used as an injection insert, the nut 342 is integrally formed by injection molding, that is, the connecting ring 343 and the nut 342 are fixed by injection molding, and then the valve core 341 and the connecting ring 343 are fixed by welding, so as to form the valve core assembly 34; referring to fig. 6, the nut 342 includes a second through hole 3421 therethrough, and an internal thread is disposed on a side wall of the second through hole 3421, and correspondingly, referring to fig. 2, an external thread matched with the internal thread is disposed at a lower end of the screw rod 36, which defines that one end of the screw rod 36 close to the valve core 341 is a lower end, one end of the screw rod 36 far from the valve core 341 is an upper end, and the screw rod 36 is connected with the valve core assembly 34 through a thread fit; referring to fig. 6, the valve plug 341 includes a receiving cavity 3411, a portion of the nut 342 is located in the receiving cavity 3411, the receiving cavity 3411 is disposed in communication with the second through hole 3421, in this embodiment, the valve plug assembly 34 further includes an elastic component 344, the elastic component 344 is located in the receiving cavity 3411, one end of the elastic component 344 abuts against the valve plug 341, the other end of the elastic component 344 abuts against the nut 342, and the elastic component 344 is disposed to facilitate eliminating backlash between the screw rod 36 and the valve plug assembly 34 in threaded engagement; the valve core 341 further includes a communication hole 3412, the communication hole 3412 is communicated with the receiving cavity 3411, and the communication hole 3412 is provided to balance the pressure of the working medium at two ends of the valve core assembly 34, specifically, referring to fig. 1, the working medium flows into the receiving cavity 3411 from the communication hole 3412, that is, one end of the valve core assembly 34, and flows into the other end of the valve core assembly 34 through a gap where the screw rod 36 is in threaded fit with the valve core assembly 34, so as to balance the pressure of the working medium between two ends of the valve core assembly 34, and to reduce the influence of the pressure difference of the working medium at two ends of the valve core assembly 34 on the movement of the valve core assembly 34, so. Referring to fig. 5, the nut 342 further includes a limiting portion 3422, the limiting portion 3422 is a non-rotating body, the structure of the limiting portion 3422 may be various as long as the valve core assembly 34 can be prevented from rotating circumferentially, in this embodiment, the number of the limiting portions 3422 is four, the limiting portion 3422 includes a limiting portion side surface 34221, and the limiting portion side surface 34221 includes an arc surface and a square plane.

Referring to fig. 7 and 8, the connecting member 32 includes a first mounting portion 321, the first mounting portion 321 has a first mounting cavity 322, the first mounting portion 321 includes a first step portion 3211, a matching portion 3212 and a second step portion 3213, the first step portion 3211 is disposed closer to an opening of the first mounting cavity 322 than the matching portion 3212, the matching portion 3212 is disposed closer to the opening of the first mounting cavity 322 than the second step portion 3213, that is, the matching portion 3212 is located between the first step portion 3211 and the second step portion 3213, and the matching portion 3212 includes a matching surface 32121; referring to fig. 2, at least a portion of the valve core assembly 34 is located in the first installation cavity 322, so that the limiting portion side surface 34221 of the nut is attached to the mating surface 32121, which can prevent the valve core assembly 34 from rotating circumferentially during movement; referring to fig. 7 and 8, in the present embodiment, the valve seat 33 and the connecting member 32 are in interference fit, so as to achieve the fixed connection between the valve seat 33 and the connecting member 32, but as another embodiment, the valve seat 33 and the connecting member 32 may also be integrally formed; the valve seat 33 includes at least one flow hole 331 and a valve port 332, the flow hole 331 is disposed to communicate with the valve port 332, and the first mounting chamber 322 is disposed to communicate with the valve port 332.

Referring to fig. 1 and 2, the valve member 3 further comprises a first bearing member 37 and a second bearing member 38, the sleeve 35 comprises a body side wall 351 and a top portion 352, the sleeve 35 is integrally formed, the sleeve 35 is provided with a mounting cavity 353, the first bearing member 37 is pressed into the mounting cavity 353 and is positioned in the mounting cavity 353 close to the top portion 352 or is abutted against the top portion 352, and the first bearing member 37 is tightly fixed with the sleeve 35; part of the second bearing piece 38 is located in the first mounting cavity 322 of the connecting portion 32, the second bearing piece 38 abuts against the first stepped portion 3211 and is limited by the first stepped portion 3211, and the second bearing piece 38 and the first mounting portion 321 are fixed in an interference fit manner or fixed in a welding manner; the upper end of the screw rod 36 is movably connected with a first bearing part 37; the lower end of the screw rod 36 passes through the third through hole of the second bearing piece 38, is positioned in the first mounting cavity 322 of the connecting piece 32, and is in threaded connection with the valve core assembly 34; sleeve 35 is located at the radial periphery of rotor assembly 31, or rotor assembly 31 is located in assembly chamber 353, and sleeve 35 is welded to connecting member 32 through the free end of body sidewall 351; the rotor assembly 31 is limited by the first bearing piece 37 and the second bearing piece 38, specifically, a part of the first bearing piece 37 is located in the first recessed cavity 3122 of the bracket 312, and a part of the second bearing piece 38 is located in the second recessed cavity 3123 of the bracket 312, so that the rotor assembly 31 is limited axially by the bracket 312 and the first bearing piece 37 and the second bearing piece 38, and in addition, a part of the first bearing piece 37 is located in the first recessed cavity 3122, and a part of the second bearing piece 38 is located in the second recessed cavity 3123, which is beneficial for reducing the axial height of the valve member 3, i.e., the volume of the electronic expansion valve; the screw 36 is tightly fitted and fixed with the bracket 312, that is, the rotor assembly 31 and the screw 36 are axially limited by the first bearing 37 and the second bearing 38 at the same time, and further, graphite gaskets may be additionally arranged between the first bearing 37 and the bracket 312 and/or between the second bearing 38 and the bracket 312 to reduce friction loss between the bracket 312 and the first bearing 37 and/or the second bearing 38 during rotation. Because the first bearing 37 and the second bearing 38 are axially limited, the rotor assembly 31 drives the screw rod 36 to circumferentially rotate together under the excitation of the magnetic field of the stator assembly 2, the screw rod 36 is in threaded connection with the valve core assembly 34, and because the valve core assembly 34 is circumferentially limited by the limiting portion 3422 and the matching portion 3212 of the connecting piece 32, namely, the valve core assembly 34 cannot circumferentially rotate along with the screw rod 36, thus, under the action of the threads, the valve core assembly 34 vertically reciprocates along the axial direction of the first mounting cavity 322, so that the valve core 341 adjusts the opening degree of the valve port 332 by being close to or far from the valve port 332. It should be noted that, in order to enable the valve core assembly 34 to reciprocate up and down along the axial direction of the first mounting cavity 322, that is, along the axial direction of the first mounting cavity 322, the height H of the installation matching portion 3212 is greater than the height L of the limiting portion 3422; defining an axial direction along the first mounting cavity 322, the movement of the valve core assembly 34 near the second bearing 38 is an upward movement, the movement of the valve core assembly 34 away from the second bearing 38 is a downward movement, the valve core assembly 34 is limited by the second bearing 38 during the upward movement, and the valve core assembly 34 is limited by the second step portion 3213 or the valve port 332 during the downward movement.

Referring to fig. 9, the valve body 4 includes a first port 41, a second port 42, a second mounting portion 43 and a first channel 44, the second mounting portion 43 has a second mounting cavity 45, the first channel 44 communicates the first port 41 and the second port 42 through the second mounting cavity 45, the first port 41 and the second port 42 are located on different sides of the valve body 4, an opening of the second mounting cavity 45 is located on one side of the valve body 4, and the three sides are different sides of the valve body 4, which is beneficial to avoiding interference and improving the utilization rate of the valve body 4. Referring to fig. 1, a part of the valve member 3 is located in the second mounting chamber 45, when the first channel 44 communicates with the first port 41 and the second port 42 through the valve port 332, the valve member 3 is fixedly connected with the second mounting portion 43, specifically, referring to fig. 8, the connecting member 32 further comprises a first flange portion 323 and a first side portion 324, and the outer surface of the first side portion 324 is formed with an external thread; accordingly, referring to fig. 9, the second mounting portion 43 includes a second side portion 431, the second side portion 431 being formed with an internal thread to be fitted with the external thread of the first side portion 324; referring to fig. 1, part of the valve member 3 is located in the second mounting cavity 45, the valve member 3 is rotated, the first side portion 324 and the second side portion 431 are in threaded fit, the first flange portion 323 abuts against the opening side of the second mounting cavity 45 of the valve body 4, and the first flange portion 323 is pressed against the opening side of the second mounting cavity, so that the valve member 3 and the valve body 4 are relatively fixed; further, the valve member 3 and the valve body 4 can be arranged in a sealing manner, so that the risk that the working medium leaks outwards from a threaded connection gap between the valve member 3 and the valve body 4 is reduced.

Referring to fig. 10 to 13, the second embodiment is a technical solution, and the main difference between the technical solution of the second embodiment and the technical solution of the first embodiment is that: the connection between the valve element 3 'and the valve body 4' is different and the sleeve 35 'and the connecting piece 32' are different.

Referring to fig. 11, in the present embodiment, the sleeve 35 ' includes a body sidewall 351 ', a top portion 352 ', and a flange 353 ', the flange 353 ' is located at one end of the body sidewall 351 ', the top portion 352 ' is located at the other end of the body sidewall 351 ', and the sleeve 35 ' is integrally formed; referring to fig. 12, the connector 32 'includes a first flange portion 323' and a first side portion 324 ', the first flange portion 323' including a first end face 3231 'and a second end face 3232'; referring to fig. 11, a portion of the body sidewall 351 'of the sleeve 35' is located at a radially outer periphery of the rotor assembly 31, the portion of the body sidewall 351 'is located at a radially outer periphery of the first side portion 324', and the cuff 353 'abuts the first flange portion 323', specifically the first end face 3231 'of the first flange portion 323'.

Referring to fig. 13, the valve body 4 includes a second mounting portion 43 ', the second mounting portion 43' having a second mounting cavity 45 ', the second mounting portion 43' including a second side portion 431 'and a third stepped portion 432', the second side portion 431 'being disposed closer to an opening of the second mounting cavity 45' than the third stepped portion 432 ', the second side portion 431' being formed with an internal thread; referring to fig. 10, the electronic expansion valve 100 ' includes a first compression nut 5, an outer circumferential surface of the first compression nut 5 is formed with an external thread to be engaged with an internal thread of a second side portion 431 ', a part of the valve member 3 ' is located in a second mounting chamber 45 ', the first compression nut 5 is located at a radial outer circumference of a sleeve 35 ', the first compression nut 5 is rotated, the first compression nut 5 is screw-engaged with a second side portion 431 ' of a valve body 4 ', the first compression nut 5 is brought into abutment with a flange 353 ', the flange 353 ' is brought into abutment with a first end face 3231 ' of a first flange portion 323 ', a second end face 3232 ' of the first flange portion 323 ' is brought into abutment with a third step portion 432 ', such that, by rotating the first compression nut 5, the flange 353 ' is compressed between the first compression nut 5 and the first flange portion 323 ', relative fixation of the sleeve 35 ' and a connecting member 32 ' is ensured, and at the same time, the first flange portion 323 ' and the flange portion 353 ' are compressed between the third step portion 432 ' and the first compression nut 5, ensuring a relative fixation of the valve part 3 'and the valve body 4'. Furthermore, the valve component 3 'and the valve body 4' can be arranged in a sealing manner, so that the risk that the working medium leaks outwards from the fit clearance between the valve component 3 'and the valve body 4' is reduced; a sealing arrangement may also be provided between the sleeve 35 'and the connector 32', which is advantageous for reducing the risk of leakage of the working medium out of the fitting gap between the connector 32 'and the sleeve 35'. Compared with the first embodiment in which the sleeve 35 ' and the connecting member 32 ' are fixed by the first gland nut 5, the sleeve 35 ' and the connecting member 32 ' are assembled and fixed, so that one welding process can be reduced, which is beneficial to simplifying the assembly of the electronic expansion valve 100 '.

Referring to fig. 14, compared to the second embodiment, in the third embodiment, the sleeve 35 ' does not include the flange 353 ', that is, the sleeve 35 ' is welded and fixed to the connecting member 32 ', and the first compression nut 5 is rotated to compress the first flange 323 ' between the third step portion 432 ' of the valve body 4 ' and the first compression nut 5, so as to ensure the relative fixation of the valve member 3 ' and the valve body 4 '.

Referring to fig. 15, which is a technical solution of the fourth embodiment, compared with the second embodiment, in the fourth embodiment, the valve core assembly 34 ' includes a valve core 341 and a nut 342 ', the valve core 341 is used as an injection insert, and the nut 342 ' is integrally formed by injection molding, that is, the nut 342 ' and the valve core 341 are fixedly formed by injection molding to form the valve core assembly 34 '. It is of course conceivable that in the fourth embodiment the sleeve 35 'and the connecting piece 32' can also be fixed by welding or the valve part 3 'and the valve body 4' can also be fixed by screwing.

It should be noted that: although the present invention has been described in detail with reference to the above-mentioned embodiments, it should be understood by those skilled in the art that the present invention may be modified and equivalents may be substituted for those skilled in the art, and all technical solutions and modifications that do not depart from the spirit and scope of the present invention should be covered by the claims of the present invention.

Claims

1. An electronic expansion valve, includes control division, stator module, valve member and valve body, the control division with stator module is connected, the valve member with the valve body is connected, stator module is located the periphery of valve member, stator module with the valve body is connected, its characterized in that: the valve part comprises a rotor assembly, a sleeve, a connecting piece, a first bearing piece and a second bearing piece, the rotor assembly comprises a support, the support comprises a first concave cavity and a second concave cavity, the sleeve is located at the periphery of the rotor assembly, the sleeve is fixedly connected with the connecting piece, the connecting piece is fixedly connected with the valve body, the sleeve comprises an assembly cavity, the first bearing piece is located in the assembly cavity and fixedly connected with the sleeve, part of the first bearing piece is located in the first concave cavity, the second bearing piece is fixedly connected with the connecting piece, part of the second bearing piece is located in the second concave cavity, and the rotor assembly is axially limited through the first bearing piece and the second bearing piece.

2. The electronic expansion valve of claim 1, wherein: the valve component also comprises a valve core assembly and a screw rod, the screw rod is fixedly connected with the rotor assembly, and the lower end of the screw rod is in threaded connection with the valve core assembly; the valve core assembly comprises a nut, the nut comprises a limiting part, the limiting part is a non-rotating body, and the limiting part comprises a limiting part side face; the connecting piece comprises a first mounting part, the first mounting part is provided with a first mounting cavity, the first mounting part comprises a matching part, the matching part comprises a matching surface, at least part of the valve core assembly is positioned in the first mounting cavity, the side surface of the limiting part is attached to the matching surface, and the valve core assembly is circumferentially rotated and limited through the limiting part and the matching part; along the axial direction of first installation cavity, the height of cooperation portion is greater than the height of spacing portion.

3. The electronic expansion valve of claim 2, wherein: the valve core assembly further comprises a valve core, a connecting ring and an elastic component, the connecting ring is used as an injection molding insert, the nut is integrally formed in an injection molding mode, and the valve core and the connecting ring are welded and fixed; the valve core comprises an accommodating cavity and a communicating hole, the accommodating cavity is communicated with the communicating hole, part of the nut is positioned in the accommodating cavity, the elastic component is positioned in the accommodating cavity, one end of the elastic component is abutted to the valve core, and the other end of the elastic component is abutted to the nut.

4. The electronic expansion valve of claim 2, wherein: the valve core assembly further comprises a valve core, the valve core is used as an injection molding insert, the nut is formed through integral injection molding, the valve core comprises an accommodating cavity and a communicating hole, part of the nut is located in the accommodating cavity, and the accommodating cavity is communicated with the communicating hole.

5. An electronic expansion valve according to claim 3 or 4, wherein: the first mounting portion comprises a first step portion and a second step portion, the matching portion is located between the first step portion and the second step portion, the second bearing is abutted against the first step portion, and the second bearing is fixedly connected with the first mounting portion; the valve component is provided with a valve port, the valve core assembly is limited by the second bearing piece during upward movement, and the valve core assembly is limited by the second step part or the valve port during downward movement.

6. The electronic expansion valve of claim 5, wherein: the valve body comprises a first port, a second installation part and a first channel, the second installation part is provided with a second installation cavity, the first port and the second port are positioned on different sides of the valve body, an opening of the second installation cavity is positioned on the other side of the valve body, and the three sides are different sides of the valve body; part of the valve member is positioned in the second mounting cavity, the valve member is fixedly connected with the second mounting part, and the first channel is communicated with the first port and the second port through the valve port.

7. The electronic expansion valve of claim 6, wherein: the sleeve comprises a main body side wall, and the sleeve is welded and fixed with the connecting piece through the free end part of the main body side wall; the connecting piece still includes first flange portion and first lateral part, first lateral part is formed with the external screw thread, the second installation department includes the second lateral part, the second lateral part is formed with the internal thread, first lateral part with second lateral part threaded connection, first flange portion compress tightly in the valve body the opening side of second installation cavity.

8. The electronic expansion valve of claim 6, wherein: the sleeve pipe includes the turn-ups, the connecting piece includes first flange portion, the turn-ups with first flange portion butt, the second installation department includes second lateral part and third step portion, the second lateral part is compared third step portion is close to the opening setting of second installation cavity, the second lateral part is formed with the internal thread, electronic expansion valve includes first gland nut, first gland nut is located sheathed tube periphery, first gland nut with second lateral part threaded connection, first gland nut compresses tightly the turn-ups in first gland nut with between the first flange portion, first gland nut compresses tightly first flange portion with the turn-ups in first gland nut with between the third step portion.

9. The electronic expansion valve of claim 6, wherein: the sleeve comprises a main body side wall, and the sleeve is welded and fixed with the connecting piece through the free end part of the main body side wall; the connecting piece includes first flange portion, the second installation department includes second lateral part and third step portion, the second lateral part is compared third step portion is close to the opening setting of second installation cavity, the second lateral part is formed with the internal thread, electronic expansion valve still includes first gland nut, first gland nut's outer peripheral face is formed with the external screw thread, first gland nut is located the periphery of connecting piece, first gland nut with second lateral part threaded connection, first gland nut compresses tightly first flange portion in third step portion.