CN110296222B

CN110296222B - Electronic expansion valve

Info

Publication number: CN110296222B
Application number: CN201811596745.3A
Authority: CN
Inventors: 请求不公布姓名
Original assignee: Zhejiang Sanhua Intelligent Controls Co Ltd
Current assignee: Zhejiang Sanhua Intelligent Controls Co Ltd
Priority date: 2018-03-23
Filing date: 2018-12-26
Publication date: 2023-05-23
Anticipated expiration: 2038-12-26
Also published as: CN110296222A

Abstract

The invention discloses an electronic expansion valve, which comprises a valve body, wherein the valve body forms a valve cavity and is provided with a valve port, a rotor assembly comprises a rotor and a screw rod, the screw rod is provided with an external thread part and a screw rod step part, a connecting piece is fixedly connected with the screw rod, a support frame is directly or indirectly fixedly connected with the valve body, the support frame is provided with an end table top, the end table top is matched with the screw rod step part, a core assembly comprises a nut, the nut is provided with an internal thread part matched with the external thread part, the core assembly performs axial lifting movement to approach or be far away from the valve port through the threaded matching action of the external thread part and the internal thread part, the electronic expansion valve can perform axial limiting on the screw rod through the support frame and the connecting piece, the screw rod and the rotor always keep rotating in a product operation state, and the rotating movement of the screw rod is directly converted into axial lifting movement of the core assembly through the threaded matching action.

Description

Electronic expansion valve

Technical Field

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

Background

Referring to fig. 1, fig. 1 shows a typical electronic expansion valve product structure, which includes a base 1, a valve body 2, and a housing assembly, wherein the base 1 is fixedly connected with the valve body 2, and the base 1 is provided with a valve port 11, the housing assembly includes a first housing 31 and a second housing 32, the first housing 31 and the second housing 32 are fixedly connected, the first housing 31 is formed with a first inner cavity, a driving part is accommodated in the first inner cavity, the second housing 32 is formed with a second inner cavity, a transmission part is accommodated in the second inner cavity, the driving part includes a rotor part 41, a rotation shaft 42 is further penetrated in the center of the driving part, the transmission part includes a gear reduction gear mechanism, the gear reduction gear mechanism is a multi-stage gear reduction mechanism including a sun gear, a primary gear and a secondary gear, the secondary gear is fixedly connected with a lead screw 43, the lead screw 43 and the valve needle 7 make the valve needle 7 approach or separate from the valve port 11 through screw-thread cooperation to adjust the flow rate of a refrigerant flowing through the valve port 11, and the working principle of the product is as follows: the electronic expansion valve is transmitted to the driving part under the pulse action, the rotor part 41 is driven to rotate, the rotating shaft 42 drives the sun gear to rotate along with the rotation of the rotor, the secondary gears are driven to axially rotate by the transmission action of the gears of all stages of the transmission part, the valve needle 7 axially lifts and lowers to approach or separate from the valve port 11 under the thread matching action of the screw rod 43 and the nut, and finally the flow regulation purpose is achieved. The electronic expansion valve product structure is designed to improve precision and the valve opening driving force, a speed reducing gear mechanism is arranged, the whole size of the product is increased, in order to enable the screw 43 to rotate only in the circumferential direction, the screw 43 and the secondary gear are fixedly connected, the outer periphery of the secondary gear is fixedly provided with a bearing part, the upper part of the bearing part is stopped by a clamping ring, and the lower part of the bearing part is stopped by a clamping ring to prevent the screw 43 from moving in the vertical direction.

Disclosure of Invention

The invention provides the electronic expansion valve, which has a simpler overall structure and can limit the axial movement of the screw rod.

The invention provides an electronic expansion valve, which comprises a valve body, wherein the valve body is provided with a valve cavity and a valve port; the rotor assembly comprises a rotor and a screw rod, and the screw rod is provided with an external thread part and a screw rod step part; the support frame is directly or indirectly fixedly connected with the valve body and is provided with an end table top, and the step part of the screw rod is in abutting fit with the end table top; the connecting piece is fixedly connected with the screw rod and is in butt fit with the end table top; the core body assembly comprises a nut, the nut is provided with an internal thread part matched with the external thread part, and the core body assembly can be close to or far away from the valve port in the valve cavity under the action of the threaded matching of the external thread part and the internal thread part.

According to the electronic expansion valve provided by the invention, a reduction gear device and other parts in the background technology are eliminated, the movement of the screw rod in the axial direction is limited through the cooperation of the stepped part of the screw rod and the support frame and the cooperation of the connecting piece and the support frame, the screw rod is always kept to rotate in the circumferential direction when the electronic expansion valve acts, and the whole structure of the electronic expansion valve is simpler.

Drawings

FIG. 1 is a schematic diagram of a typical electronic expansion valve;

FIG. 2 is a schematic diagram of a first embodiment of an electronic expansion valve according to the present invention;

FIG. 3 is a schematic view of a support frame structure of an electronic expansion valve according to the present invention;

FIG. 4 is a schematic diagram of a second embodiment of an electronic expansion valve according to the present invention;

Detailed Description

In order to make the technical solution of the present invention better understood by those skilled in the art, the following detailed description of the present invention is provided with reference to the accompanying drawings and specific embodiments, and the description of the embodiments provided in the specification is merely illustrative of the preferred embodiments of the electronic expansion valve provided in the present invention, and not all embodiments are included, but other embodiments with reasonable expansion should be included in the scope of the present invention.

Referring to fig. 2, fig. 2 is a schematic diagram of a first specific embodiment of an electronic expansion valve provided by the present invention, the electronic expansion valve includes a valve body 10, the valve body 10 is formed with a valve cavity in a substantially cylindrical structure, the valve body 10 is provided with a valve port 101, the valve port 101 is matched with a core component 60, in addition, the electronic expansion valve structure may also be provided with a valve seat 20, the valve body 10 and the valve seat 20 may be used as separate components, the valve body 10 and the valve seat 20 may be welded and fixed during assembly, the valve port 101 may be provided on the valve seat 20, a first connection port is provided on a side wall of the valve body 10 by a stamping method, a second connection port is provided on a lower end portion of the valve body 10, the first connection port is welded and fixed with a first connection pipe 100, the second connection pipe 200 is welded and fixed with the second connection pipe 100, the first connection pipe 100 and the second connection pipe 200 are conducted through the valve port 101, and a refrigerant may flow out of the second connection pipe 200 through the valve port 101 after entering the valve cavity, or a refrigerant may flow out of the valve cavity through the first connection pipe 100 through the valve port 101, and the electronic expansion valve has a bidirectional flow function.

The upper end portion of the valve body 10 is fixedly welded with the connecting seat 30, the connecting seat 30 comprises a connecting seat body 31, a guide wall 32 and a protruding portion 33, the connecting seat 30 is further provided with a guide hole 321, the connecting seat body 31 is fixedly welded with the valve body 10 after being press-fitted into the valve cavity, the connecting seat 30 is integrally fixedly installed on the valve body 10, specifically, the outer peripheral wall of the connecting seat body 31 is fixedly welded with the inner peripheral wall of the valve body 10, the guide wall 32 extends into the valve cavity, at least one part of the core assembly 60 can extend into the valve cavity through the guide hole 321 and can axially move up and down along the guide hole 321, the connecting seat body 31 is provided with a first step portion 311, the first step portion 311 forms a first step surface 3111, the protruding portion 33 is provided with a second step portion 331, and the second step portion 331 is fixedly welded with a shell 90.

The housing 90 and the connection base 30 together form a rotor cavity, the rotor cavity accommodates the rotor assembly 40, the rotor assembly 40 comprises a rotor 41, a fixing seat 42 integrally injection-molded with the rotor and a screw rod 44, the fixing seat 42 is provided with a guide portion 421, the guide portion 421 is provided with a guide hole 4211, the guide hole 4211 is fixedly connected with a screw rod end 443, the rotor 41 is driven to rotate by a coil sleeved on the outer periphery of the housing 90, the rotation of the rotor 41 drives the fixing seat 42 to rotate, the screw rod 44 rotates accordingly, the screw rod 44 is provided with a screw rod step portion 441, and the screw rod 44 is fixedly connected with the connection piece 80.

As shown in fig. 3, the electronic expansion valve further includes a support frame 50, where the support frame 50 includes an upper support frame 51 and a lower support frame 52, and the support frame 50 is welded and fixed to the connection seat 30, specifically, the support frame 50 is integrally and fixedly mounted to the connection seat 30 by welding and fixing the outer peripheral wall of the lower support frame 52 and the inner peripheral wall of the protruding portion 33, the support frame 50 is fixedly connected to the valve body 10 by the connection seat 30, and when the connection seat 30 and the valve body 10 are in an integral structure, the support frame 50 is directly welded and fixed to the valve body 10, and the support frame 50 can be directly or indirectly welded and fixed to the valve body 10. The wall of the lower support frame 52 is provided with a matching groove 53, the matching groove 53 is matched with a nut 61 to limit the circumferential position of the core assembly 60 so as to prevent the core assembly 60 from rotating in the circumferential direction, the support frame 50 is also provided with a limiting hole 54 matched with the screw rod 44, the screw rod 44 passes through the limiting hole 54 to be matched with the core assembly 60, the support frame 50 is provided with an end table 511, the end table 511 comprises an upper end table 5111 and a lower end table 5112, the upper support frame 51 forms the upper end table 5111, the lower support frame 52 forms the lower end table 5112, the lower end table 5112 is matched and abutted with the screw rod stepped portion 441 so as to prevent the screw rod 44 from moving in the axial direction upwards in a serial manner, the upper end table 5111 is abutted with a connecting piece 80 so as to prevent the screw rod 44 from moving in the axial direction downwards in a serial manner, specifically, the connecting piece 80 is fixedly connected with the screw rod 44, the screw rod 44 is prevented from moving in the axial direction downwards in a serial manner through the abutting action of the limiting hole 54 of the retainer frame 50 and the upper end table 5111, the screw rod 44 is prevented from moving in the axial direction in the limiting action of the axial direction of the upper end table 5112, the lower support frame 51 can not be matched with the screw rod 44 in the axial direction with the axial direction of the end table surface 41, namely, the axial direction can always be matched with the end table seat 41 in the axial direction with the axial direction, and the axial direction can be always be matched with the end table 41, and the axial position can be always be the axial position with the axial position can be the end table 41.

The electronic expansion valve further comprises a core body assembly 60, the core body assembly 60 comprises a nut 61 and a valve needle 62, the nut 61 comprises a nut body 611, the nut body 611 is press-fit into the valve needle cavity 621, the nut 61 comprises a connecting piece 612, the nut body 611 and the connecting piece 612 can be made of metal materials, when the nut body 611 is made of metal materials, the connecting piece 612 and the nut body 611 are integrally injection molded, the nut 61 or the specific materials of the connecting piece 612 are not limited, the nut 61 further comprises a connecting piece 613, the connecting piece 613 extends outwards from the nut body 611 and protrudes, the nut 61 is fixedly connected with the valve needle 62 integrally through the welding of the lower end face of the connecting piece 612 and the end face of the valve needle 62, the nut body 611 is provided with a nut mounting hole 614 for the screw 44 to pass through, the nut 61 is provided with an inner threaded portion 60a in threaded connection with an outer threaded portion 44a of the screw 44, the screw 44 is converted into axial lifting movement of the core body assembly 60 through the threaded cooperation of the screw 44 and the nut 61, the connecting piece 613 can be clamped in the clamping groove 53 and can only perform limiting action on the axial lifting movement of the support frame 60 in the circumferential direction of the axial direction and the axial direction of the support frame 60, and the axial direction of the axial lifting movement of the support frame assembly 50 can be limited by the axial direction 50 can be limited by the axial movement of the axial direction 50. The valve needle 61 is of a hollow approximately equal-diameter cylindrical structure, and comprises a valve head 622 and a valve needle body 623, wherein the valve head 622 is close to or far away from the valve port 101 by the axial lifting movement of the core component 60 so as to regulate the flow rate of refrigerant flowing through the valve port 101, clearance fit is arranged between the outer wall of the valve needle body 623 and the guide wall 32, the valve needle body 623 extends into the valve cavity through the guide hole 321, the valve needle body 623 can axially move along the guide wall 32, and the guide wall 32 of the connecting seat 30 provides a guide effect for the valve needle 62 so that the coaxiality between the valve needle 62 and the central axis of the valve port 101 is kept so as to improve the stability and reliability of the electronic expansion valve during operation.

In order to balance the pressures of the valve needle cavity 621, the valve cavity and the rotor cavity when the electronic expansion valve is actuated, as shown in fig. 1, the valve head 622 is abutted against the valve port 101 in the valve closing state, if the refrigerant enters the valve body 10 from the second connecting pipe 200, the core assembly 60 and the screw rod 44 and other components are impacted by a certain refrigerant pressure, if the refrigerant with higher pressure without the sealing member 70 directly punches the valve head 622 out of the valve port 101 to make the valve head 622 not reach the valve closing effect, and meanwhile, the screw rod 44 also has a certain impact force, specifically, the sealing member 70 comprises a gasket, an O-shaped rubber ring and a pressing sheet, the sealing member 70 can also only comprise an O-shaped rubber ring and a pressing sheet, the sealing member 70 is positioned between the second step surface 3111 and the lower end part of the lower support frame 52, the gasket or the O-shaped rubber ring is abutted against the second step surface 6111, and the pressing sheet is fitted into the protrusion 30 to fix the O-shaped rubber ring.

In the following description, in connection with the simple description of the operating principle of the electronic expansion valve, the rotor assembly 40 drives the rotor 41 to rotate by excitation, the fixing seat 42 rotates simultaneously with the rotor 41, the screw rod 44 rotates along with the circumferential direction, because the screw rod 44 and the supporting frame 50 and the connecting piece 80 and the supporting frame 50 cooperate with each other to perform circumferential rotation only and do not perform axial lifting movement, the core assembly 60 performs axial lifting movement by the threaded cooperation of the external threaded portion 44a of the screw rod 44 and the internal threaded portion 60a of the nut 61, and the connecting piece 613 also performs axial lifting movement along the cooperating groove 53 to enable the valve head 622 to approach or separate from the valve port 101 to regulate the flow of the refrigerant flowing through the valve port 101, it is to be noted that when the valve head 622 is in cooperating abutment with the valve port 101, the connecting piece 613 is relatively close to the lower portion of the cooperating groove 53, and when the valve head 622 is far from the valve port 101, the connecting piece 613 is relatively close to the upper portion of the cooperating groove 53, and when the valve head 622 is furthest from the valve port 101, the connecting piece 613 can abut against the top wall 521 of the lower supporting frame 52. The electronic expansion valve structure eliminates other complex part structures such as a gear reduction mechanism and a bearing in the background art, can limit the up-down moving position of the screw rod 44 only through the support frame 50 and the connecting piece 80, simplifies the whole assembly structure of the product, ensures that the rotor 41 and the screw rod 44 always keep in circumferential rotation without displacement, ensures that the axial dimension reduction of the product is convenient for realizing the miniaturization of the whole structure of the product, further reduces the manufacturing cost, ensures that the rotor 41 keeps circumferential rotation in the process of the electronic expansion valve, reduces the dimension of the fixed coil driving device arranged on the outer periphery of the shell part 9, fully plays the magnetic force action of the rotor 41 because the central shaft of the rotor 41 keeps being matched with the central shaft of the coil driving part, further reduces the driving force required in the process of the operation, the core assembly 60 located below the screw rod 44 cannot perform circumferential rotation under the clamping action of the matching groove 53 of the supporting frame 50 and the connecting piece 613, axial lifting movement can be performed only under the drive of the screw rod 44, the electronic expansion valve is subjected to coil excitation, the rotation movement of the screw rod 44 is gradually and directly converted into lifting movement of the core assembly 60 along the guide wall 32 through the threaded matching action of the external thread part 44a and the internal thread part 60a to regulate the flow rate of the refrigerant flowing through the valve port 101, the electronic expansion valve structure belongs to a direct-acting driving mode, and compared with the background art, the valve opening and closing can be smoothly realized even though the driving force is smaller, the flow regulation precision and the opening and closing valve can be kept, and the flow regulation precision and the opening and closing valve can be controlled by increasing the reduction ratio without using a complex reduction gear mechanism.

As shown in fig. 4, a second embodiment of the electronic expansion valve according to the present invention is shown, the difference between this embodiment and the first embodiment is that the connecting piece 80 is a sleeve, the sleeve is generally hollow and cylindrical structure, the sleeve is fixedly connected with the screw 44, specifically, the inner wall of the sleeve is welded and fixed with the screw 44, the lower end surface of the sleeve is matched and abutted against the upper end surface 5111 to prevent the screw 44 from axially displacing downwards, when the electronic expansion valve is actuated by excitation, the sleeve and the screw 44 rotate together in the circumferential direction, the lower end surface of the sleeve can rotate relative to the upper end surface 5111 of the support frame 50, the screw stepped portion 441 of the screw 44 is matched and abutted against the lower end surface 5112 to prevent the screw from axially moving upwards, the limiting action of the sleeve and the support frame 50 on the screw 44 prevents the screw 44 from moving upwards and downwards, in the working state, it is necessary to describe that the positions of the sleeve and the screw stepped portion 441 are also mutually matched and abutted against the lower end surface 5112, specifically, the upper end surface of the sleeve and the lower end surface 5112 are matched and abutted against the upper end surface 5112 to mutually abut against the upper end surface 5112, and the upper end surface of the screw 44 is not mutually matched and abutted against the screw 44 in the axial direction, and the same principle is not shown in the axial direction, and the other embodiment is implemented.

The description of ordinal numbers such as "first, second, third", and the like, and the description of orientation words such as "upper, lower, middle, inner, and outer", in the present invention, are merely introduced for convenience of description, and are not to be construed as limiting the order in which the components of the present invention are described.

According to the electronic expansion valve provided by the invention, the limiting effect on the screw rod and the rotor can be realized through the connecting piece and the supporting frame, the screw rod and the rotor always keep rotating in the circumferential direction and do not perform up-down movement when the electronic expansion valve is operated, and the rotating movement of the screw rod is directly converted into the lifting movement of the core body assembly in the axial direction through the threaded matching effect.

The foregoing is merely a preferred embodiment of the present invention, and it should be noted that it will be apparent to those skilled in the art that several modifications and variations can be made without departing from the scope of the invention.

Claims

1. An electronic expansion valve, comprising:

a valve body (10), wherein the valve body (10) is provided with a valve cavity and a valve port (101);

a rotor assembly (40), wherein the rotor assembly (40) comprises a rotor (41) and a screw rod (44), and the screw rod (44) is provided with an external thread part (44 a) and a screw rod step part (441);

the support frame (50), the said support frame (50) is connected with said valve block (10) fixedly directly or indirectly, the said support frame (50) has end mesa (511), the said lead screw step (441) cooperates with said end mesa (511) in an abutting joint;

the connecting piece (80), the connecting piece (80) is fixedly connected with the screw rod (44), the connecting piece (80) is in abutting fit with the end table top (511), and the connecting piece (80) is a check ring or a shaft sleeve;

the valve comprises a core assembly (60), wherein the core assembly (60) comprises a nut (61), the nut (61) is provided with an inner threaded portion (60 a) matched with the outer threaded portion (44 a), and the core assembly (60) can move in an axial lifting mode in the valve cavity to be close to or far away from the valve port (101) through the threaded matching action of the outer threaded portion (44 a) and the inner threaded portion (60 a).

2. The electronic expansion valve according to claim 1, characterized in that the electronic expansion valve comprises a connecting seat (30), the connecting seat (30) is fixedly connected with the valve body (10), and the supporting frame (50) is fixedly connected with the connecting seat (30).

3. The electronic expansion valve according to claim 2, characterized in that the connection seat (30) is press-fitted into the valve cavity, the connection seat (30) comprising a body (31) and a protrusion (33), the body (31) having a first step (311), the protrusion (33) having a second step (331).

4. An electronic expansion valve according to claim 3, wherein the first step portion (311) forms a first step surface (3111), a sealing member (70) is accommodated between the first step surface (3111) and the support frame (50), and the second step portion (331) is fixedly connected to the housing (90).

5. The electronic expansion valve according to claim 4, wherein the connecting seat (30) is further provided with a guide wall (32) and a guide hole (321), the core assembly (60) comprises a valve needle (62), the valve needle (62) is fixedly connected with the nut (61), the guide hole (321) is matched with the valve needle (62), and the valve needle (62) can move in an axial lifting manner along the guide wall (32).

6. The electronic expansion valve according to claim 1, wherein the support frame (50) is provided with a fitting groove (53) and a limiting hole (54), the nut (61) has a fitting portion (613), and the fitting portion (613) is fitted with the fitting groove (53).

7. The electronic expansion valve according to claim 6, wherein the support frame (50) comprises an upper support frame (51) and a lower support frame (52), the end table top (511) comprises an upper end table top (5111) and a lower end table top (5112), the lower support frame (52) is provided with the matching groove (53), and the matching portion (613) can be abutted with a top wall surface (521) of the lower support frame (52).

8. The electronic expansion valve according to claim 7, wherein the retainer ring is fixedly connected to the screw (44), the retainer ring abuts against the upper end surface (5111), and the screw step (441) abuts against the lower end surface (5112).

9. The electronic expansion valve according to claim 7, wherein the retainer ring is fixedly connected to the screw (44), the retainer ring abuts against the lower end surface (5112), and the screw step (441) abuts against the upper end surface (5111).

10. The electronic expansion valve according to claim 7, wherein the sleeve is fixedly connected to the screw rod (44), a lower end surface of the sleeve is in abutting engagement with the upper end surface (5111), the sleeve and the screw rod (44) are rotatable relative to the upper end surface (5111), and the screw rod stepped portion (441) is in abutting engagement with the lower end surface (5112).

11. The electronic expansion valve according to claim 7, wherein the sleeve is fixedly connected to the screw rod (44), an upper end surface of the sleeve is in abutting engagement with the lower end surface (5112), the sleeve and the screw rod (44) are rotatable relative to the lower end surface (5112), and the screw rod stepped portion (441) is in abutting engagement with the upper end surface (5111).