CN113623413A - Electronic expansion valve - Google Patents

Abstract

An electronic expansion valve comprises a valve body, a connecting seat, a core body assembly, a sealing element and a screw rod, wherein the connecting seat is fixedly connected with the valve body, the core body assembly comprises a valve core assembly and a nut, the valve core assembly comprises a limiting element and a valve core, the limiting element is fixedly connected with the valve core, the nut is in limiting connection with the valve core assembly, the nut can move in the axial direction, the screw rod is in threaded fit with the nut, the sealing element is positioned at the outer peripheral part of the valve core, abuts against the valve core, the sealing element abuts against the connecting seat, the valve core comprises a valve head, when the valve head abuts against the valve port part, the position where the valve head abuts against the valve port part is defined as a first abutting part, the position where the valve core abuts against the sealing element is a second abutting part, the projection area of the second abutting part facing the valve port end face in the axial direction is positioned at the outer side of the first abutting part, the first abutting part is used as a boundary, and a gap is formed between the valve head close to one side of the nut and the valve port end face, the electronic expansion valve comprises an elastic element, one end of the elastic element is abutted against the nut, and the other end of the elastic element is abutted against the valve core.

Description

Electronic expansion valve

[ technical field ] A method for producing a semiconductor device

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

[ background of the invention ]

An electronic expansion valve is generally applied to a refrigeration system as a throttling element to adjust the flow of a refrigerant, a rotor is generally driven to rotate by a coil part, and the rotor drives a thread of a transmission part to drive a valve needle part to perform lifting motion in the axial direction so as to control the opening degree of a valve to realize the flow adjustment of the refrigerant.

How to reduce the situation that the valve core is separated from the valve port due to the influence of the pressure of the refrigerant when the valve is closed is a technical problem to be solved urgently by those skilled in the art.

[ summary of the invention ]

The invention aims to provide an electronic expansion valve with a novel structure, which enables a valve core to be well abutted with a valve port part in a valve closing state.

The invention provides an electronic expansion valve, which comprises a valve body, a connecting seat, a core body assembly, a sealing element and a screw rod, wherein the valve body is provided with a valve opening part, the connecting seat is provided with a guide hole, the connecting seat is fixedly connected with the valve body, the core body assembly comprises a valve core assembly and a nut, the valve core assembly comprises a limiting piece and a valve core, the limiting piece is fixedly connected with the valve core, the nut is in limiting connection with the valve core assembly, the nut can move in the axial direction, the screw rod is in threaded fit with the nut, the core body assembly can perform axial lifting motion along the guide hole, the sealing element is positioned on the periphery of the valve core, the sealing element is abutted against the valve core and the connecting seat, the valve core comprises a valve head, when the valve head is abutted against the valve opening part, the part abutted against the valve head and the valve opening part is defined as a first abutting part, the position where the valve core abuts against the sealing element is defined as a second abutting position, the valve body comprises a valve port end face, a projection area of the second abutting position facing the valve port end face in the axial direction is located on the outer side of the first abutting position, the first abutting position is used as a boundary, a gap is formed between the valve head close to one side of the nut and the valve port end face, the electronic expansion valve further comprises an elastic element, one end of the elastic element abuts against the nut, and the other end of the elastic element abuts against the valve core.

According to the electronic expansion valve provided by the invention, through the optimized design of the core body assembly structure, the elastic element is additionally arranged, one end of the elastic element is abutted against the nut, and the other end of the elastic element is abutted against the valve core, so that the valve core can be well abutted against the valve port when the electronic expansion valve is in a valve-closed state.

[ description of the drawings ]

Fig. 1 is a sectional view of the overall structure of an electronic expansion valve provided by the present invention;

fig. 2 is a cross-sectional view of the whole structure of the core assembly of the electronic expansion valve provided by the invention when the core assembly is in an open valve state;

fig. 3 is a side perspective view of a core assembly of the electronic expansion valve provided in the present invention and an overall structural sectional view of the core assembly in a valve-closed state;

FIG. 4 is a schematic view of a gasket of an electronic expansion valve provided in accordance with the present invention;

FIG. 5 is a schematic view of an elastic element of the electronic expansion valve according to the present invention;

FIG. 6 is a schematic view of another elastic element structure of the electronic expansion valve provided in the present invention;

fig. 7 is a sectional view of an electronic expansion valve provided in accordance with the present invention, in which another elastic member is installed in a core assembly;

fig. 8 is a cross-sectional view of the overall structure of another embodiment of the electronic expansion valve provided in the present invention;

FIG. 9 is an enlarged schematic view of a core assembly structure of the electronic expansion valve of FIG. 8;

fig. 10 is a projection view of a first abutting portion and a second abutting portion of the electronic expansion valve provided by the present invention;

fig. 11 is a schematic cross-sectional view of a first abutting portion and a second abutting portion of the electronic expansion valve according to the present invention;

FIG. 12 is an enlarged schematic view of the first abutment portion of FIG. 11;

FIG. 13 is a schematic view of a flow curve of an electronic expansion valve without an elastic member and with an elastic member according to the present invention

[ detailed description ] embodiments

In order to make those skilled in the art better understand the technical solution of the present invention, the following detailed description is made with reference to the accompanying drawings and specific embodiments.

It should be noted that the electronic expansion valve provided by the present invention has optimized design of the core body assembly structure, and the structures of other parts such as the connecting seat, the limiting seat, the bearing, the rotor screw rod assembly, and the like of the electronic expansion valve are only exemplified, and on the basis of having similar functions, other structures can be substituted to be applied to the electronic expansion valve structure provided by the present invention, and the electronic expansion valve structure also belongs to the protection scope of the present invention.

The invention provides an electronic expansion valve, which comprises a valve cavity 102, a valve body 10, a connecting seat 70, a core body assembly 90, a sealing element 80 and a screw rod 43, wherein the valve body is provided with a valve opening 101, the connecting seat 70 comprises a guide hole 71, the connecting seat 70 is fixedly connected with the valve body 10, the core body assembly 90 comprises a valve core assembly and a nut 92, the valve core assembly comprises a limiting element 93 and a valve core 91, the limiting element 93 can be fixedly connected with the valve core 91 through welding and the like after being press-fitted into the valve core 91, the nut 92 is in limiting connection with the valve core assembly, the nut 92 is limited on the valve core 91 by the limiting element 93, the nut 92 can move in the axial direction, the sealing element 80 is positioned on the outer periphery of the valve core 91 and is abutted against the valve core 91, the sealing element 80 is abutted against the connecting seat 70, the screw rod 43 is provided with an external thread part 432, the nut 92 is provided with an internal thread part 921, and is matched with the thread of an internal thread 921 through the external thread part 432, the valve core 91 can perform axial lifting movement along the guide hole 71 in the valve cavity 102 to approach or separate from the valve port 101, the valve core 91 comprises a valve head 914, when the valve head 914 abuts against the valve port 101, the position where the valve head 914 abuts against the valve port 101 is defined as a first abutting part A1, the position where the sealing member 80 abuts against the valve core 91 is defined as a second abutting part A2, the valve body 10 comprises a valve port end surface 10a, the second abutting part is formed with a projection B area facing the valve port end surface 10a in the axial direction, the projection B area is located outside the first abutting part A1, the first abutting part A1 is used as a boundary, a gap is formed between the valve head 914 close to one side of the nut 92 and the valve port end surface 10a, namely a gap S1 is formed between the valve head 914 above the first abutting part A1 and the valve port end surface 10a, the electronic expansion valve provided by the invention further comprises an elastic element, one end of the elastic element abuts against the nut 92, the other end of the elastic element is abutted against the valve core 91, the invention optimizes the whole structure of the core body assembly 90 of the electronic expansion valve and adds the elastic element, when the electronic expansion valve is in a valve closing state, the valve head 914 of the valve core 91 abuts against the valve opening part 101, refrigerant enters the valve cavity 102 from the first connecting pipe 20 and easily generates upward acting force on the valve needle 91 through the gap S1, the elastic element can enable the valve head 914 to be in an abutting state with the valve opening part 101, in addition, when the valve opening state is switched gradually, particularly from the valve closing state to the valve opening process, the nut 92 can always abut against the limiting part 93 under the acting force of the elastic element, so that the valve core actuation can be prevented from being influenced by differential pressure, the condition of up-down movement can not be generated, and the stability of flow regulation of the electronic expansion valve can be maintained.

The valve body 91 includes a valve body and a valve head 914, the valve head 914 has a substantially reverse tapered configuration, and the position of contact with the valve port 101 is a first contact portion a1, the position of contact between the seal 80 and the valve body of the valve body 91 is a second contact portion a2, and the first contact portion a1 and the second contact portion a2 according to the present invention are both formed in the valve body 91.

Referring to fig. 1-3, a first embodiment of an electronic expansion valve structure according to the present invention will be described in detail, where the electronic expansion valve includes a valve body 10, a first connection pipe 20 and a second connection pipe 30, the valve body 10 is substantially a cylindrical structure with openings at both upper and lower sides, and can be integrally formed by using a stainless steel material, the valve body 10 is provided with a valve opening 101, the valve body 10 can also be formed by a split machine, when the split machine is formed, the valve body 10 can include a valve body and a valve opening, the valve body and the valve opening are fixedly connected by welding after being respectively formed, when the valve body is formed by a split machine, the valve opening is located at the valve opening 101, the valve opening is a part of the valve body 10, a side wall of the valve body 10 is provided with a first connection port, a lower end of the valve body 10 is provided with a second connection port, the first connection pipe 20 is fixedly connected to the valve body 10 through the first connection port, the second connecting pipe 30 is fixedly connected with the valve body 10 through a second connecting port, the electronic expansion valve has a valve chamber 102, and the refrigerant enters the valve chamber 102 from the first connecting pipe 20, passes through the valve port 101, and then flows out from the second connecting pipe 30, or the refrigerant can flow in a reverse direction, enters the valve chamber 102 from the second connecting pipe 30 through the valve port 101, and then flows out from the first connecting pipe 20.

The electronic expansion valve further comprises a connecting seat 70, a core body assembly 90, a rotor screw rod assembly 40 and a housing, wherein the connecting seat 70 is fixedly connected with the valve body 10, the connecting seat 70 can also be made of stainless steel material and at least partially extends into a valve cavity 102, the housing is fixedly connected with the upper end of the connecting seat 70, the housing 10, the connecting seat 70 and the valve body 10 roughly define the valve cavity 102, the electronic expansion valve is explained in a state that the core body assembly is abutted against a valve port 101 in a closed valve state, the valve cavity 102 is divided into an upper cavity 102A and a lower cavity 102B, the upper cavity 102A, i.e. a back pressure cavity, is roughly positioned above a step 73 of the connecting seat, the lower cavity 102B is roughly positioned below the step 73 of the connecting seat, a coil device (not shown) is sleeved on the outer peripheral part of the housing, the rotor screw rod assembly 40 is roughly positioned in the upper cavity 102A and comprises a rotor 41, a rotor seat 42 and a screw rod 43, the rotor 41 and the rotor base 42 are integrally injection molded, the rotor base 42 includes a connection guide portion 421, the connection guide portion 421 is provided with a connection guide hole 4211 adapted to an upper end of the lead screw 43, and the upper end of the lead screw 43 is fixedly connected to the connection guide portion 421, the rotor base 42 and the lead screw 43 can synchronously rotate when the rotor 41 rotates under the action of the excitation coil of the coil device, in order to prevent the lead screw 43 from moving in the axial direction, the electronic expansion valve further includes an upper step abutting against a lower end surface of the rotor base 42, the electronic expansion valve further includes a limit base 50 and a bearing 60, the limit base 50 is substantially in a cap-shaped structure with a smaller diameter, the limit base 50 is fixedly connected to the connection base 70, specifically, the upper limit base 51 and the lower limit base 52 are included, the upper limit base 51 includes an extension wall 511, the lower limit base 52 is provided with at least one limit groove 53, in this embodiment, two correspondingly provided limit grooves 53 are exemplified, the limiting seat 50 further has a mounting cavity 51 and a communication hole 54, the lead screw 43 extends into the valve cavity 102 through the communication hole 54 to be in threaded fit with the nut 92 of the core body assembly 90, the mounting cavity 51 accommodates the bearing 60, the bearing 60 includes an inner ring, an outer ring and a rolling element located between the inner ring and the outer ring, wherein the inner ring is fixedly connected with the lead screw 43, the outer ring is fixedly connected with the extension wall 511, the lead screw step 431 abuts against the bearing 60, and through the abutting action of the upper end step and the rotor seat 42 and the abutting action of the lead screw step 431 and the bearing 60, the lead screw is limited in the axial direction to avoid the movement of the lead screw in the axial direction, when the electronic expansion valve is actuated, the lead screw 43 can be always kept to rotate in the circumferential direction and cannot perform lifting movement in the axial direction.

The core assembly 90 can perform axial lifting motion synchronously through the screw-thread matching action of the screw rod 43 and the nut 92, the flange portion 922 of the nut 92 can also perform axial lifting motion along the limiting groove 53, the limiting seat 50 further has a limiting groove surface 531, when the flange portion 922 upwards abuts against the limiting groove surface 531, the core assembly 90 is relatively far away from the valve port 101, in order to keep the refrigerant pressure on the upper side and the lower side of the valve core balanced, the electronic expansion valve further comprises a sealing element 80, in the embodiment, the sealing element 80 comprises a pressing plate, a sealing ring and a sealing gasket, the sealing gasket and the sealing ring are positioned on the connecting seat step 73, the sealing gasket is positioned on the periphery of the valve core 91 and abuts against the valve core 91, the sealing ring is sleeved on the periphery of the sealing gasket and abuts against the connecting seat 70, the refrigerant can be prevented from leaking outwards from the sealing position through the abutment of the sealing element 80, the valve core 91 and the connecting seat 70, and the pressing plate is positioned above the sealing ring and the sealing gasket and abuts against the sealing ring, the lower end of the lower limiting seat 52 is fixedly connected with the connecting seat 70 to press and limit the pressing plate of the sealing element 80 on the connecting seat 70, the sealing element 80 is located at the periphery of the valve core 91 and abuts against the valve core 91 to isolate a back pressure cavity and a valve cavity which are located above the core body assembly, and it should be noted that the sealing element 80 can also be directly sleeved on the valve core 91 to perform axial lifting movement together with the core body assembly 90. The connecting seat 70 further includes a guide hole 71 and a guide wall, the guide hole 71 is in clearance fit with the valve core 91 and provides a guide function for the valve core 91 so as to facilitate coaxial fit of the valve core 91 and the valve port 101, and the core body assembly 90 can perform axial lifting motion along the guide wall in the valve cavity.

The following describes a structure of the nut and the screw, in which the nut 92 has an internal thread portion 921 which is in threaded engagement with an external thread portion 432 of the screw 43, the screw 43 can lift and lower the core assembly 90 in the valve chamber 102 in an axial direction to approach or separate from the valve port 101 by the thread engagement to adjust the flow rate of the refrigerant flowing through the valve port of the valve port 101, the nut 92 further includes a first nut inner hole having a diameter larger than that of the first nut inner hole, and a second nut inner hole having a smooth section, the screw 43 can lift and lower the core assembly 90 in an axial direction by the thread engagement of the internal thread portion 921 and the external thread portion 432, the screw 43 rotates only in a circumferential direction, the core assembly 90 performs an axial movement of ascending or descending, and the screw 43 can freely extend into the second nut inner hole, the invention provides an electronic expansion valve, wherein a nut step 924 is arranged between a first nut inner hole and a second nut inner hole, a screw rod end surface 433 is arranged at the lower end of a screw rod 43, and the screw rod end surface 433 is positioned below the nut step 924, the external thread part 432 of the screw rod 43 and the internal thread part 921 of the nut can always keep a meshed state no matter in an open valve state or a closed valve state, so that the wear of the screw rod on teeth in the actuating process can be prevented, the service life of parts can be prolonged, if the screw rod end surface 433 is positioned above the nut step 924, in the repeated actuating process of the electronic expansion valve, the screw rod can possibly generate certain shaking in the radial direction due to the influence of the deviation of the process machining size, so that the teeth of the internal thread part 921 are damaged, and the service life of the parts is influenced.

The structure of the core body assembly 90 is described below with reference to fig. 2 and 3, where the core body assembly 90 includes a core body assembly and a nut 92, the core body assembly includes a core 91 and a limit piece 93, the core 91 is fixedly connected to the limit piece 93, specifically, the limit piece 93 may be fixed by welding after being press-fitted and fixed to the core 91 or may be fixed by directly welding both the limit piece 93 and the core 91, the core 91 may be made of stainless steel, when the valve head 914 abuts against the valve port 101, the core body 91 has a first abutting portion a1 of the electronic expansion valve, and in this state, the sealing element 80 abuts against the core 91 and has a second abutting portion a2 of the electronic expansion valve, the valve body 10 includes a valve port end face 10a, the second abutting portion a2 forms a projection B region facing the valve port end face 10a in the axial direction, the projection B region is an orthographic projection, and the projection B region is located outside the first abutting portion a1, the valve head 914 above the first abutting portion a1 has a gap S1 from the valve port end face 10a, the valve head 914 below the first abutting portion a1 extends into the valve port portion, the first abutting portion a1 and the second abutting portion a2 are both formed on the valve core 91, that is, the first abutting portion a1 is used as a boundary, a gap S1 is formed between the valve head 914 on the side relatively close to the nut 92 and the valve port end face 10a, and the orthogonal projection of the second abutting portion a2 towards the valve port end face 10a is an annular projection, as shown in fig. 10, a plan view from the valve core 91, an annular projection B area is located outside the first abutting portion a1, the electronic expansion valve has a valve core cavity 910, preferably, the valve core body of the valve core 91 may be a hollow cylindrical structure with an equal diameter, which is more convenient for processing and manufacturing, and here, the valve core body with an equal diameter structure refers to the valve core 91 except for the valve head 914, the valve core 91 is in small clearance fit with the guide wall of the connecting seat 70 and can perform axial lifting motion along the guide hole 71, the diameter of the valve core 91 is larger than the diameter of the valve port 101, similarly, the diameter of the valve core 91 refers to the diameter of the valve core body part of the valve core 91 except for the opening valve head 914, the valve core 91 can also be in other structural states with unequal diameters, for example, when the valve head is in a state of abutting against the valve port 101, a flange or a concave structure can be arranged on the valve core 91 between the second abutting part a2 and the first abutting part a1, or a flange or a concave structure can be arranged above the second abutting part a2, and the like, only the forward projection B area of the second abutting part a2 is required to be located outside the first abutting part a1 and a gap S1 is formed between the valve head and the valve port end face of the refrigerant, by the design, when the valve is in a valve closing state, the pressure from the second connecting pipe 30 can enter the upper cavity 102A back pressure cavity above the core assembly 90 through the valve core cavity 910, therefore, the pressures at the upper and lower ends of the valve core 91 are substantially balanced, while the pressure of the refrigerant from the first connection pipe 20 forms an upward force-bearing area on the valve core 91 through the gap S1, the pressure difference formed between the first connection pipe 20 and the second connection pipe 30 and the force-bearing area form a pressure to make the valve core 91 move upward, further, the valve core 91 further comprises a valve head 914 capable of abutting against the valve port 101, the valve core 91 is further internally provided with a first step part 911, the upper end part of the valve core 91 is further provided with a valve core groove 912 and a second step part, the nut 92 comprises a body 923 and a flange 922 protruding from the body in the radial direction, in this embodiment, the two flange parts 922 are provided and symmetrically arranged, the two corresponding valve core grooves 912 are provided, the flange parts 922 are embedded into the valve core groove 912 to be matched therewith, the limiting piece 93 can be installed into the valve core 91 through the opening at the upper end part in an interference manner to abut against the second step part, then, the limiting member 93 and the valve core 91 can be fixedly connected by welding, the nut 92 is integrally limited on the valve core 91, the body portion located below the flange portion 922 is inserted into the valve core cavity 910, the body portion located above the flange portion 922 and the limiting member 93 form a large clearance fit, the side portion of the body portion 923 is provided with a cut-out portion 9231, a vent groove of the electronic expansion valve is formed between the cut-out portion 9231 and the valve core 91, when a refrigerant enters the valve core cavity 910 from the second connecting pipe 30, the refrigerant enters the upper cavity 102A from the vent groove, so that the pressure of the refrigerant above and below the valve core 91 can be balanced to facilitate the normal operation of the electronic expansion valve, the nut 92 cannot be separated from the valve core 91 by the action of the limiting member 93, the valve core assembly 90 is formed by the valve core assembly and the nut, specifically, the limiting member 93, the nut 92 and the valve core 91 together form the core assembly 90 of the electronic expansion valve, and the lower end of the limiting member 93 is provided with a limiting end surface 931, the spool groove 912 includes a groove side wall and a bottom wall 9121, a height H1 is formed between the limit end surface 931 and the bottom wall 9121, a height H2 is set for a flange portion 922 of the nut 92, wherein the height H1 is greater than the height H2 so that the nut 92 can move axially with a small clearance between the spool groove 912 and the limit member 93, the inclination of the spool 91 can be automatically corrected by guiding the nut 92 to swing left and right by setting the small clearance when the spool 91 abuts against the valve port 101, the coaxial engagement of the spool 91 and the valve port 101 is realized, the width W1 is set for the spool groove 912, the width W2 is set for the flange portion 922, wherein W1 is greater than or equal to W2 so that the nut 92 cannot rotate at least in the circumferential direction, the flange portion 922 further includes an upper flange surface 9221 and a lower flange surface 9222, the valve head 914 of the spool 91 and the valve port portion engage with each other by a screw thread when the valve head abuts against the valve port, the nut 92 continues to move downward until a clearance L9221 and the limit end surface 931 form a clearance L1 and a clearance between the lower end surface 1 and the lower end surface 1 when the upper flange portion 931 abuts against the valve port portion The third step portions 915 of the cores 91 abut; as shown in fig. 2, when the valve head 914 of the valve core 91 is relatively distant from the valve port 101 in the valve-open state, the upper flange surface 9221 gradually approaches the stopper end surface 931 until it abuts against the stopper end surface 931, the clearance between the lower flange surface 9222 and the bottom wall 9121 increases, and the nut lower end surface is relatively distant from the third step portion 915; as shown in fig. 3, when the valve is closed, the valve head 914 abuts against the valve port 101, a gap L1 is formed between the upper flange surface 9221 and the limit end surface 931, and a gap is maintained between the lower flange surface 9222 and the bottom wall 9121 while the lower end surface of the nut abuts against the third step portion 915.

Of course, a structural design that the lower flange surface 9222 abuts against the bottom wall 9121 may be adopted, the nut 92 can still move in the axial direction between the bottom wall and the limiting end surface, when the valve is closed, a gap L1 is formed between the upper flange surface 9221 and the limiting end surface 931, and the lower flange surface 9222 abuts against the bottom wall 9121; when the electronic expansion valve is in a valve-open state, the upper flange surface 9221 abuts against the limit end surface 931, a gap is formed between the lower flange surface 9222 and the bottom wall 9121, the electronic expansion valve further includes an elastic element 300, the elastic element 300 is located in the valve core chamber 910 of the electronic expansion valve, and the lower end of the elastic element 300 abuts against the first step portion 911, the upper end of the elastic element 300 abuts against the lower end surface of the nut 92, it should be noted that the abutting meaning stated in this specification includes direct abutting and indirect abutting, the upper end of the elastic element 300 abuts against the lower end surface of the nut through the gasket 400 when the elastic element abuts against the first step portion 911, the lower end of the elastic element 300 also abuts against the first step portion 911 through the gasket 400, as shown in fig. 4, the disk-shaped refrigerant structure with a plurality of through holes 401 substantially arranged on the gasket 400 may also be a polygonal refrigerant structure, the specific material and structure of the gasket 400 are not limited, and the through holes 401 facilitate the upper and lower pressure of the valve core chamber 102A from the second connection pipe 30 to balance the upper pressure and the lower pressure of the valve core 91, the washer is additionally arranged between the lower end face of the nut and the elastic element 300 to realize indirect offset between the elastic element 300 and the nut 92, the matching stress area of the nut 92 can be relatively increased, the hidden danger that the upper end part of the elastic element 300 bites into the lower end face of the nut under the condition that the electronic expansion valve is actuated for a long time can be effectively avoided, and the structure of the elastic element 300 can be a compression coil spring in the embodiment.

By additionally arranging the elastic element 300, when the valve is closed, the valve head 914 of the valve core 91 abuts against the valve port 101, when the refrigerant enters the valve cavity 102 from the first connecting pipe 20, because the sealing element 80 is arranged on the outer periphery of the valve core 91, the refrigerant cannot flow out from the gap between the valve core and the connecting seat after entering the valve cavity 102, so that the refrigerant is easy to generate upward acting force on the valve core 91 through the gap S1 when gathering in the valve cavity 102, the valve core 91 can be always kept in an abutting state with the valve port 101 under the acting force of the elastic element 300, the hidden danger that the refrigerant leaks from the disengaged gap due to the disengagement of the valve head 914 from the valve port 101 is avoided, and the actuation reliability of the electronic expansion valve is relatively ensured.

In addition, the addition of the elastic element 300 is beneficial to ensuring the flow stability of the electronic expansion valve, when the electronic expansion valve is switched from a closed valve state to an open valve state without the elastic element 300, the coil component sleeved on the outer periphery of the shell is electrified, the rotor 41 starts to rotate under the influence of the excitation action of the coil, the screw rod 43 synchronously and circumferentially rotates along with the coil, the flange portion 922 of the nut 92 gradually moves upwards to eliminate the gap L1 between the upper flange end surface 9221 and the limit end surface 931 until the two abut against each other under the screw matching action of the external screw portion 432 of the screw rod 43 and the internal screw portion 921 of the nut 92, meanwhile, the gap between the lower flange end surface 9222 and the bottom wall 9121 gradually increases, the lower end surface of the nut gradually moves away from the first step portion 911 and forms a gap with the first step portion 911, the core assembly 90 axially lifts up, the valve head 914 gradually moves away from the valve head portion 101, the refrigerant enters the valve cavity 102 from the second connecting pipe 30, then enters the upper cavity 102A through the valve core cavity 910, because the upper and lower pressures of the valve core 91 are approximately balanced, a gap S1 is formed between the valve head 914 above the first abutting part a1 and the valve port end surface 10a, the refrigerant entering the valve cavity 102 from the first connecting pipe 20 applies an additional upward acting force to the valve core 91 through the gap S1, the valve core 91 is easy to move upwards due to the influence of the pressure difference force, so that a gap is formed between the upper flange end surface 9221 and the limiting end surface 931 from the original abutting state, the gap between the lower flange surface 9222 and the bottom wall 9121 is reduced, a nut moving gap exists between the external thread part of the screw rod 43 and the internal thread part of the nut 92, the nut moving gap is similar to the valve opening pulse of the electronic expansion valve, and the valve core 91 can move upwards after each pulse adjustment is completed, the screw rod drives the valve core 91 and the nut 92 to have certain hysteresis, so that flow deviation can occur in each flow regulation process, and finally a flow curve without an elastic part is formed as shown in fig. 13, but the electronic expansion valve provided by the invention adds the elastic element 300 in the valve core cavity 910, so that the upper end of the elastic element 300 is abutted against the nut end surface of the nut 92, and the other end is abutted against the first step part 911, when the valve core cavity is switched from a closed valve state to an open valve state, the nut 92 is acted by the elastic force of the elastic element 300 to be pushed upwards, during the open valve process, the upper flange surface 9221 can always be abutted against the limit end surface 931, a gap is left between the lower flange surface 9222 and the bottom wall 9121, no additional nut movable gap can be generated between the external thread part of the screw rod 43 and the thread part 921 of the nut 92, and the valve core 91 is not influenced by pressure difference force to generate the possibility of being connected upwards, the valve core 91 and the nut 92 can follow in time and the pulse driving of the corresponding screw rod has no hysteresis, each pulse flow adjustment is stable, and a flow curve chart provided with an elastic part is formed as shown in fig. 13.

Another structure of the elastic element of the electronic expansion valve according to the present invention is described with reference to fig. 5, which is different from the above-mentioned elastic element in the specific structure of the elastic support 300a, the elastic support 300a includes a support body 301a and support columns 302a, the support body 301a is substantially hollow disk-shaped, a plurality of support columns 302a extend upward from the support body 301a, the support section 302a includes a lateral wall portion 3021a and a vertical wall portion 3022a, the vertical wall portion extends in an axial direction, the lateral wall portion extends in a radial direction from the vertical wall portion, the lateral wall portion and the vertical wall portion are connected by a bending portion 3023a, the support body 301a abuts against the first step portion 911, and the lateral wall portion 3021a of the support column 302a abuts against a lower end surface of a nut. As shown in fig. 6 and 7, the elastic element may be an elastic support 300a ' having another structure, the elastic support 300a ' includes a flat portion 301a ' and a claw portion 302a ', the claw portion 302a ' extends downward from the flat portion in the circumferential direction, the flat portion 301a ' abuts against the lower end surface of the nut, and the claw portion 302a ' abuts against the first stepped portion 911.

The upper end of the elastic element can abut against the nut, the lower end of the elastic element can abut against the valve core, in addition, the lower end of the elastic element can also realize indirect abutment against the valve core by additionally arranging a third part, the electronic expansion valve can also comprise a stop part 200, specifically, the stop part 200 can be an elastic clamping ring which is approximately in a C-shaped gap, a clamping groove is formed in the valve core 91, the clamping ring is embedded into the clamping groove to realize limiting connection between the clamping ring and the clamping groove, the lower end of the elastic element 300 can also abut against the stop part 200 directly, and the technical effect of the invention can also be realized.

The second embodiment of the electronic expansion valve provided by the present invention is described with reference to fig. 8 and 9, and is different from the first embodiment in that the position of the elastic element is set, the electronic expansion valve has a valve core cavity 910 'and a mounting portion C, a fourth step portion 916 and an extending portion 917 are further provided in the valve core 91, the extending portion 917 extends upward from the periphery of the fourth step portion 916, the diameter of the valve core cavity 910' above the fourth step portion 916 is larger than the diameter of the valve core cavity 910 'below the fourth step portion 916, the body portion 923 includes an upper body 9232 and a lower body 9233, the upper body 9232 is substantially above the flange portion 922, the lower 9233 is substantially below the flange portion 922, the lower body 9233 is located below the valve core cavity 910', the extending portion 917, the body 923 below the flange portion 922, and the fourth step portion 916 substantially form the mounting portion C of the electronic expansion valve, the elastic element 300 is located in the mounting portion C and sleeved on the outer periphery of the lower body 9233, the upper end of the elastic element 300 abuts against the flange portion 922 of the nut 92, the lower end of the elastic element 300 abuts against the fourth stepped portion 916, similarly, the elastic element 300 can also abut against the valve element 91 through a third component, a clamping groove can be formed in the extension portion 917 and the stopper can be embedded, indirect abutment between the lower end of the elastic element 300 and the valve element through the stopper can be achieved through the mode, in addition, a gasket can be arranged between the elastic element and the nut 92 to reduce the force-bearing area, related technical effects are described in detail in the first embodiment, and are not repeated one by one.

It should be noted that, in the present specification, the terms "first, second" and the like, or the terms "upper and lower" and the like are introduced for convenience of description based on the drawings of the specification, and there is no limitation in any order or direction. It should be noted that, for those skilled in the art, it is possible to make various improvements and modifications to the present invention without departing from the principle of the present invention, and those improvements and modifications also fall within the scope of the claims of the present invention.

Claims (12)

1. An electronic expansion valve is characterized by comprising a valve body, a connecting seat, a core body assembly, a sealing element and a screw rod, wherein the valve body is provided with a valve opening part, the connecting seat is provided with a guide hole, the connecting seat is fixedly connected with the valve body, the core body assembly comprises a valve core assembly and a nut, the valve core assembly comprises a limiting part and a valve core, the limiting part is fixedly connected with the valve core, the nut is in limiting connection with the valve core assembly, the nut can move in the axial direction, the screw rod is in threaded fit with the nut, the core body assembly can axially move up and down along the guide hole, the sealing element is positioned on the peripheral part of the valve core, the sealing element is abutted against the connecting seat, the valve core comprises a valve head, and when the valve head is abutted against the valve opening part, the position where the valve head is abutted against the valve opening part is defined as a first abutting part, the position where the valve core abuts against the sealing element is defined as a second abutting position, the valve body comprises a valve port end face, a projection area of the second abutting position facing the valve port end face in the axial direction is located on the outer side of the first abutting position, the first abutting position is used as a boundary, a gap is formed between the valve head close to one side of the nut and the valve port end face, the electronic expansion valve further comprises an elastic element, one end of the elastic element abuts against the nut, and the other end of the elastic element abuts against the valve core.

2. The electronic expansion valve according to claim 1, wherein the valve element has a substantially constant-diameter cylindrical structure, the outer diameter of the valve element is larger than the outer diameter of the valve port, and the elastic element is capable of keeping the valve element against the valve port when the valve is closed; when the valve is in an open state, the elastic element can enable the nut to be kept against the limiting piece.

3. The electronic expansion valve according to claim 1, wherein the electronic expansion valve has a valve core chamber, the elastic element is located in the valve core chamber, the valve core is provided with a first step portion, an upper end of the elastic element abuts against the nut, and a lower end of the elastic element abuts against the first step portion.

4. The electronic expansion valve according to claim 3, wherein the elastic member is an elastic support member, the elastic support member includes a support member body portion having a substantially hollow disk-like structure and a plurality of support columns extending upward from the support member body portion, and a support portion including a lateral wall portion, a vertical wall portion, and a curved portion, the lateral wall portion and the vertical wall portion being connected by the curved portion, the lateral wall portion extending in a radial direction, the support member body portion abutting against the first step portion, and the lateral wall portion abutting against a lower end surface of the nut.

5. The electronic expansion valve according to claim 3, wherein the elastic element is an elastic support member, the elastic support member includes a flat portion and a claw portion, the claw portion extends from the flat portion in the circumferential direction, the flat portion abuts against a lower end surface of the nut, and the claw portion abuts against the first step portion.

6. The electronic expansion valve according to claim 1, wherein the electronic expansion valve has a mounting portion, the valve element has a fourth step portion and an extending portion, the extending portion extends upward from a circumferential direction of the fourth step portion, the nut has a body portion and a flange portion, the body portion includes an upper body and a lower body, the lower body is located below the flange portion, the lower body is located in the valve element cavity, the extending portion, the fourth step portion, and the lower body substantially define the mounting portion, and the elastic element is fitted to an outer circumferential portion of the lower body and located in the mounting portion.

7. The electronic expansion valve according to claim 1, wherein the valve element includes an upper end portion provided with a second stepped portion, the stopper is press-fitted into the valve element from an opening of the upper end portion and abuts against the second stepped portion, and the nut is caused to be stopped with respect to the valve element, the nut includes a body portion inserted into the valve element chamber below the flange portion, and a flange portion, the valve element has a valve element groove into which the flange portion is fitted, the valve element groove has a bottom wall, the stopper has a stopper end surface, and the flange portion is movable between the bottom wall and the stopper end surface.

8. The electronic expansion valve according to claim 7, wherein the flange portion comprises an upper flange surface and a lower flange surface, a gap is formed between the lower flange surface and the bottom wall, the valve element is further provided with a third step portion, the nut has a nut lower end surface, the valve element has a valve head, when the valve head abuts against the valve opening portion, a gap is formed between the upper flange surface and the limiting end surface, and the nut lower end surface abuts against the third step portion; when the valve head is relatively far away from the valve opening part, the upper flange surface is abutted against the limiting end surface, and a gap is formed between the lower end surface of the nut and the third step part.

9. The electronic expansion valve according to claim 7, wherein the flange portion comprises an upper flange surface and a lower flange surface, the valve element is further provided with a third step portion, the nut has a nut lower end surface, the valve element has a valve head, when the valve head abuts against the valve opening portion, the lower flange surface abuts against the bottom wall, and a gap is formed between the upper flange surface and the limit end surface; when the valve head is relatively far away from the valve opening part, the upper flange surface is abutted against the limiting end surface, and a gap is formed between the lower flange surface and the bottom wall.

10. The electronic expansion valve according to any one of claims 1 to 5, further comprising a gasket, wherein the gasket is located between the nut and the elastic element, the elastic element abuts against a lower end face of the nut through the gasket, the gasket is provided with a plurality of through holes, the valve cavity comprises an upper valve cavity, and the through holes communicate with the upper valve cavity and the valve core cavity.

11. The electronic expansion valve according to any of claims 1-9, wherein the connecting seat has a connecting seat step, the sealing element comprises a pressing plate, a sealing ring, and a sealing gasket, the sealing ring and the sealing gasket are located on the connecting seat step, the sealing gasket is sleeved on the outer circumferential portion of the valve element, the sealing ring is sleeved on the sealing gasket, the electronic expansion valve further comprises a limiting seat, the pressing plate is limited on the connecting seat through the fixed connection between the limiting seat and the connecting seat, and the pressing plate abuts against the sealing ring and the sealing gasket.

12. The electronic expansion valve according to claim 1, wherein the nut has a first nut inner hole portion and a second nut inner hole portion, the inner hole diameter of the second nut inner hole portion is larger than the inner hole diameter of the first nut inner hole portion, the inner thread portion is located at a hole wall of the first nut inner hole portion, the second nut inner hole portion is a smooth section, the lead screw has a lead screw end surface, the nut further has a nut step, and the lead screw end surface is located below the nut step.

Images