CN115013540A

CN115013540A - Electronic expansion valve with novel grounding structure

Info

Publication number: CN115013540A
Application number: CN202210616994.4A
Authority: CN
Inventors: 不公告发明人
Original assignee: Zhejiang Jiaming New Energy Equipment Co ltd
Current assignee: Zhejiang Jiaming New Energy Equipment Co ltd
Priority date: 2022-06-01
Filing date: 2022-06-01
Publication date: 2022-09-06

Abstract

The invention relates to an electronic expansion valve with a novel grounding structure, which comprises a valve body and a coil assembly, wherein a sleeve is arranged on the valve body, a rotor assembly is arranged in the sleeve, the coil assembly is sleeved on the periphery of the sleeve, the coil assembly comprises a shell, a coil is embedded in the shell, a PCB (printed circuit board) electrically connected with the coil is arranged in the shell, and a first cavity matched with the periphery of the sleeve is formed on the inner periphery of the coil; a second cavity for placing the PCB is formed in the shell, the top of the first cavity is open and is communicated with the second cavity, and the top of the sleeve extends into the second cavity and is electrically grounded with the PCB; the outer wall of the sleeve and the inner wall of the shell are in sealing connection through a sealing structure. The electronic expansion valve provided by the invention has the advantages that the traditional injection arc top for separating the first cavity from the second cavity is abandoned, and the sleeve and the PCB are directly and electrically connected conveniently, so that the PCB can be directly grounded through the valve body.

Description

Electronic expansion valve with novel grounding structure

Technical Field

The invention relates to the technical field of electronic expansion valves, in particular to an electronic expansion valve with a novel grounding structure.

Background

The electronic expansion valve is mainly installed between the condenser and the evaporator, is a dividing point of high pressure and low pressure of the air-conditioning refrigeration system, and mainly has the functions of throttling and decompressing high-pressure refrigerant from the condenser so as to adjust and control the amount of the refrigerant entering the evaporator. The control chip on the electronic expansion valve PCB sends a pulse signal to the motor according to the command of the controller, the rotor assembly (motor rotor) drives the valve rod assembly to rotate under the drive of the pulse signal, the valve rod assembly realizes axial movement while rotating around the guide sleeve assembly under the action of the thread pair, and meanwhile, the valve needle on the valve rod assembly can approach or leave the valve port in the lower valve seat, and the purpose of adjusting the flow of the refrigerant flowing through the valve port is realized by changing the flow area.

In a coil assembly of an existing electronic expansion valve, an injection molding arc top matched with a valve body sleeve is usually arranged, two independent cavities which are not communicated with each other are formed inside and outside the injection molding arc top, one of the independent cavities is a first cavity used for being connected with the valve body sleeve, and the other independent cavity is a second cavity used for installing a PCB (printed circuit board), so that the PCB is protected, and the waterproof, dustproof and relevant salt spray test requirements of IP6K9K are met. In addition, in the conventional coil assembly, the PCB is not electrically connected to the valve body, and ESD (static discharge interference) causes a short-term large current impact to the PCB, so that a circuit near the ESD is generally affected, and further electronic components on the PCB are damaged or function of the PCB is lost, that is, EMC test is not easy to pass.

Therefore, the technical personnel in the field propose to arrange the grounding structure on the coil assembly, so that the PCB is in conductive connection with the valve body, and then the grounding function is realized through the valve body, so as to reduce the interference of electromagnetism on the PCB and related electronic components. However, the existing cavities for installing the PCB and installing the valve body sleeve are not communicated with each other, so that the existing structure for realizing the conductive connection between the PCB and the valve body is complex, inconvenient to operate and high in process difficulty.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide the electronic expansion valve with the novel grounding structure, which abandons the traditional injection arc top structure, so that a PCB (printed circuit board) and a valve body can be directly connected in a conductive manner, the process is simple, and the production cost is favorably reduced.

In order to solve the technical problems, the invention provides an electronic expansion valve with a novel grounding structure, which comprises a valve body and a coil assembly, wherein a sleeve is arranged on the valve body, a rotor assembly is arranged in the sleeve, the coil assembly is sleeved on the periphery of the sleeve and comprises a shell, a coil is embedded in the shell, a PCB (printed circuit board) electrically connected with the coil is arranged in the shell, and a first cavity matched with the periphery of the sleeve is formed in the inner periphery of the coil; a second cavity for placing the PCB is formed in the shell, the top of the first cavity is open and is communicated with the second cavity, and the top of the sleeve extends into the second cavity and is electrically grounded with the PCB; the outer wall of the sleeve and the inner wall of the shell are in sealing connection through a sealing structure.

According to the electronic expansion valve, the traditional injection arc top for separating the first cavity from the second cavity is abandoned, the top of the sleeve is exposed in the second cavity, the sleeve and the PCB are directly and electrically connected, the PCB can be directly grounded through the valve body, the circuit is prevented from being influenced by ESD, the grounding structure is simple in process and convenient to operate, the injection molding material of the shell is saved, and the cost is reduced. In addition, because the first cavity is communicated with the second cavity, in order to ensure the waterproof and dustproof requirements of the PCB, a sealing structure is further arranged between the sleeve and the shell, so that the sealing performance of the first cavity and the second cavity is improved.

Preferably, the bottom of the shell is provided with a connecting piece, and a sealing groove is formed between the top of the connecting piece and the bottom of the shell; the sealing structure comprises a sealing ring, the sealing ring is installed in the sealing groove, and the sealing ring is tightly sleeved on the periphery of the lower part of the sleeve. By adopting the structure, the mounting process of the sealing ring is simple and the assembly is convenient; and the sealing washer is located telescopic lower part periphery, can follow source department sealed first chamber, and sealed effect is better.

Preferably, the casing includes body and lid, the second chamber with first chamber distributes from top to bottom in the body, just the top of second chamber is uncovered, the lid is established the uncovered department in top of second chamber. During the equipment, the operator can open the department through the top of second chamber and connect PCB board and sleeve electrical ground, then establishes the uncovered department in the top of second chamber with the lid again, seals the top of second chamber.

Preferably, the PCB board and the sleeve are electrically grounded through a conductive member.

Preferably, the conductive member is a cable or a fixing piece, and both ends of the conductive member are respectively fixedly connected with the PCB board and the sleeve.

Preferably, the conductive member includes a fixing portion and an elastic portion connected to each other, the fixing portion is fixedly connected to the PCB, and the elastic portion is elastically abutted to an outer side of the sleeve. The connecting structure of the elastic part and the elastic abutting of the sleeve is adopted, the installation steps are simplified, the sleeve and the conductive piece can be ensured to be always contacted in the elastic abutting mode, and the grounding function is prevented from being influenced by the separation of the sleeve and the conductive piece.

Preferably, the elastic part is a spring.

Preferably, a mounting groove is formed in the bottom wall of the second cavity and close to the inner wall of the first cavity, and a hall element is mounted in the mounting groove. According to the invention, an injection arc top structure is abandoned, so that the distance between the Hall element and the sleeve is reduced, and the detection precision of the Hall element on the rotor in the sleeve is improved.

Preferably, the cover body and the body are fixed by laser welding, so that the cover body and the body are reliably connected, and the top sealing performance of the second cavity is ensured to be good.

Drawings

In order to more clearly illustrate the detailed description of the invention or the technical solutions in the prior art, the drawings that are needed in the detailed description of the invention or the prior art will be briefly described below. Throughout the drawings, like elements or portions are generally identified by like reference numerals. In the drawings, elements or portions are not necessarily drawn to scale.

Fig. 1 is a schematic structural diagram of an electronic expansion valve with a novel grounding structure according to a first embodiment of the present invention;

FIG. 2 is a schematic structural diagram of a valve body according to a first embodiment of the present invention;

FIG. 3 is a schematic structural diagram of a coil assembly according to a first embodiment of the present invention;

fig. 4 is a schematic view of an electrical ground connection structure of the sleeve and the PCB according to the first embodiment of the present invention;

fig. 5 is a schematic view of an electrical ground connection structure between the sleeve and the PCB according to the second embodiment of the present invention.

Reference numerals:

1-a valve body; 11-a sleeve; 12-a rotor assembly; 2-a coil assembly; 21-body; 211-a first cavity; 212-a second cavity; 22-a cover body; 23-a coil; 24-a PCB board; 25-a connector; 26-a sealing ring; 27-a conductive member; 271-a fixed part; 272-an elastic portion; 28-Hall element.

Detailed Description

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The following examples are only for illustrating the technical solutions of the present invention more clearly, and therefore are only examples, and the protection scope of the present invention is not limited thereby.

It is to be noted that, unless otherwise specified, technical or scientific terms used herein shall have the ordinary meaning as understood by those skilled in the art to which the invention pertains.

Example one

As shown in fig. 1, fig. 2, fig. 3 and fig. 4, the present embodiment discloses an electronic expansion valve with a novel grounding structure, which includes a valve body 1 and a coil assembly 2, wherein a sleeve 11 is disposed on the valve body 1, a rotor assembly 12 is disposed in the sleeve 11, the coil assembly 2 is sleeved on the periphery of the sleeve 11, the coil assembly 2 includes a housing, the housing specifically includes a body 21 with an open top and a cover 22 covering the open top of the body 21, and a coil 23 is embedded in the body 21. In this embodiment, the body 21 is an injection molded part, and in the actual production process, the coil 23 is wrapped to form the body 21 through an integral injection molding process.

A first cavity 211 matched with the outer periphery of the sleeve 11 is formed on the inner periphery of the coil 23, a second cavity 212 for placing the PCB 24 is formed inside the body 21, the coil 23 is electrically connected with the PCB 24 through a connector pin, and the connector pin is also embedded in the body 21 during injection molding. The top of the first cavity 211 is open and is communicated with the second cavity 212, and the top of the sleeve 11 extends into the second cavity 212 and is electrically grounded to the PCB 24.

The electronic expansion valve of this embodiment, abandoned traditional arc top of moulding plastics (in the current coil assembly) that is used for separating first chamber 211 and second chamber 212, injection moulding has the arc top of moulding plastics with telescopic top adaptation usually, make the top of sleeve 11 expose in second chamber 212, be convenient for sleeve 11 and PCB board 24 direct electrical ground connect, so that PCB board 24 can be through valve body 1 direct ground connection, prevent that the circuit from receiving the ESD influence, the simple process of this kind of ground structure, and the operation of being convenient for, and the material of moulding plastics of body 21 has been saved, be favorable to reduce cost.

Since the first cavity 211 and the second cavity 212 are communicated, in order to ensure the waterproof and dustproof requirements of the PCB 24, the present embodiment further provides a sealing structure between the sleeve 11 and the body 21. Specifically, the bottom of the body 21 is provided with a connecting piece 25, and a sealing groove is formed between the top of the connecting piece 25 and the bottom of the body 21; the sealing structure comprises a sealing ring 26, wherein the sealing ring 26 is arranged in the sealing groove, and the sealing ring 26 is tightly sleeved on the periphery of the lower part of the sleeve 11. During the assembly, install sealing washer 26 in the seal groove earlier, then connect the connecting piece 25 and fix the bottom at body 21 to realize fixing sealing washer 26, insert sleeve 11 at last in first chamber 211, sealing washer 26 closely supports with the cell wall of seal groove and the outer wall of sleeve 11, can carry out effectual sealed to first chamber 211 and second chamber 212. In this embodiment, the connecting member 25 and the body 21 are fixed by ultrasonic welding or hot pressing, wherein the connecting member 25 is used for being screwed with the valve body 1, so that the valve body 1 and the coil assembly 2 are relatively fixed.

The second cavity 212 and the first cavity 211 are distributed in the body 21 vertically, the top of the second cavity 212 is open, and the cover 22 covers the open top of the second cavity 212. During assembly, the operator may electrically ground the PCB board 24 and the sleeve 11 through the open top of the second cavity 212, and then laser weld the cover 22 to the open top of the second cavity 212 to seal the top of the second cavity 212.

Specifically, the PCB board 24 and the sleeve 11 are electrically grounded through the conductive member 27. In this embodiment, the conductive member 27 is a cable or a fixing piece, and two ends of the conductive member 27 are respectively welded and fixed to the PCB 24 and the sleeve 11, so as to achieve conductive connection between the PCB 24 and the sleeve 11, and further achieve conductive grounding between the PCB 24 and the valve body 1.

Further, a mounting groove is provided at a position where the bottom wall of the second chamber 212 is close to the inner wall of the first chamber 211, and a hall element 28 is mounted in the mounting groove, and the hall element 28 is used for detecting the accuracy of the rotor in the sleeve 11. The detection precision of the Hall element 28 is influenced by the distance between the Hall element and the piece to be detected, the traditional sleeve and the Hall element are separated by the injection molding arc top, so that the distance between the two is large, the detection precision of the Hall element is influenced to a certain extent, and the injection molding arc top structure is removed in the embodiment, so that the Hall element 28 can be closer to the outer wall of the sleeve 11, and the detection precision of the Hall element 28 is favorably improved.

Example two

The electronic expansion valve with the novel grounding structure provided in this embodiment has substantially the same structure as the electronic expansion valve with the novel grounding structure provided in the first embodiment, and the difference is only that the structure of the conductive member 27 is different.

Referring to fig. 5, the conductive member 27 of the present embodiment includes a fixing portion 271 and an elastic portion 272 connected to each other, the fixing portion 271 is welded to the PCB 24, one end of the elastic portion 272 is welded to the fixing portion 271, and the other end of the elastic portion 272 elastically abuts against the outer wall of the sleeve 11, specifically, the elastic portion 272 is a spring, and the elastic portion 272 and the sleeve 11 elastically abut against each other to connect, which simplifies the installation process, and the elastic abutment ensures that the sleeve 11 and the conductive member 27 always contact each other, thereby preventing the sleeve 11 and the conductive member 27 from being separated from each other and affecting the grounding function. In practice, the elastic portion 272 may also be used as other elastic conductors, such as a diaphragm contact.

In the description of the present invention, numerous specific details are set forth. It is understood, however, that embodiments of the invention may be practiced without these specific details. In some instances, well-known methods, systems, and techniques have not been shown in detail in order not to obscure an understanding of this description.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, system, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, systems, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Moreover, various embodiments or examples and features of various embodiments or examples described in this specification can be combined and combined by one skilled in the art without being mutually inconsistent.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the embodiments of the present invention, and they should be construed as being covered by the appended claims and their equivalents.

Claims

1. The utility model provides an electronic expansion valve with novel ground structure, includes valve body and coil assembly, be provided with the sleeve on the valve body, be provided with the rotor assembly in this sleeve, the coil assembly cover is established telescopic periphery, the coil assembly includes the casing, has buried the coil underground in this casing, just be provided with in the casing with the PCB board that the coil electricity is connected, its characterized in that:

a first cavity matched with the outer periphery of the sleeve is formed on the inner periphery of the coil;

a second cavity for placing the PCB is formed in the shell, the top of the first cavity is open and is communicated with the second cavity, and the top of the sleeve extends into the second cavity and is electrically grounded with the PCB;

the outer wall of the sleeve and the inner wall of the shell are in sealing connection through a sealing structure.

2. The electronic expansion valve with a novel grounding structure of claim 1, wherein:

a connecting piece is arranged at the bottom of the shell, and a sealing groove is formed between the top of the connecting piece and the bottom of the shell;

the sealing structure comprises a sealing ring, the sealing ring is installed in the sealing groove, and the sealing ring is tightly sleeved on the periphery of the lower part of the sleeve.

3. The electronic expansion valve with a novel grounding structure of claim 1, wherein:

the casing includes body and lid, the second chamber with the first chamber distributes from top to bottom in the body, just the top of second chamber is uncovered, the lid is established the uncovered department in top of second chamber.

4. The electronic expansion valve with a novel grounding structure of claim 1, wherein:

the PCB board and the sleeve are electrically grounded through a conductive piece.

5. The electronic expansion valve with a novel grounding structure as claimed in claim 4, wherein:

the conductive piece is a cable or a fixing piece, and two ends of the conductive piece are respectively fixedly connected with the PCB and the sleeve.

6. The electronic expansion valve with a novel grounding structure as claimed in claim 4, wherein:

the conductive piece comprises a fixing part and an elastic part which are mutually connected, the fixing part is fixedly connected with the PCB, and the elastic part is elastically abutted to the outer side of the sleeve.

7. The electronic expansion valve with a novel grounding structure as claimed in claim 6, wherein:

the elastic part is a spring.

8. The electronic expansion valve with a novel grounding structure of claim 1, wherein:

and a mounting groove is formed in the position, close to the inner wall of the first cavity, of the bottom wall of the second cavity, and a Hall element is mounted in the mounting groove.

9. The electronic expansion valve with novel grounding structure as claimed in claim 3, wherein:

the cover body and the body are fixed by laser welding.