A valve needle assembly and a valve device

Abstract

The present invention discloses a valve needle assembly and a valve device, wherein the valve needle assembly comprises a bellows, a valve stem and a valve needle, the valve stem comprises a first section and a second section, the bellows is sleeved on the first section and fixedly connected to the valve stem; and further comprises an adapter sleeve, the adapter sleeve is installed on the second section, the valve needle is provided with an assembly hole, the adapter sleeve is at least partially located in the assembly hole, and the valve needle and the adapter sleeve are welded and fixed. The axial size of the valve needle assembly provided by the present invention is adjustable, which can effectively offset the size fluctuation of the bellows, thereby simplifying the design of the valve seat and the assembly of the valve needle assembly and the valve seat.

Description

Technical Field

[0001] The present invention relates to the technical field of refrigeration control, and in particular to a valve needle assembly and a valve device. Background Art

[0002] The valve device in the form of an electronic expansion valve includes a valve seat and a valve needle assembly. The valve needle assembly includes a bellows, a valve stem and a valve needle. The valve stem and the valve needle are interference-fitted, and the bellows and the valve stem are welded and fixed. Since the bellows is an elastic part, its dimensional consistency is poor, which will cause the axial dimension of the entire valve needle assembly to fluctuate, which is not conducive to the design of the valve seat and the reliable assembly of the valve needle assembly and the valve seat, and further affects the reliability of the valve device in opening and closing the valve during subsequent use. Summary of the invention

[0003] The object of the present invention is to provide a valve needle assembly and a valve device, wherein the axial dimension of the valve needle assembly is adjustable, which can effectively offset the dimensional fluctuation of the bellows, thereby simplifying the design of the valve seat and the assembly of the valve needle assembly and the valve seat.

[0004] In order to solve the above technical problems, the present invention provides a valve needle assembly, including a bellows, a valve stem and a valve needle, the valve stem including a first section and a second section, the bellows is sleeved on the first section and fixedly connected to the valve stem; it also includes an adapter sleeve, the adapter sleeve is installed on the second section, the valve needle is provided with an assembly hole, the adapter sleeve is at least partially located in the assembly hole, and the valve needle and the adapter sleeve are welded and fixed.

[0005] By adopting this scheme, since the outer diameter of the adapter sleeve is smaller than the inner diameter of the assembly hole, there is a clearance fit between the adapter sleeve and the valve needle, and the installation position of the valve needle relative to the adapter sleeve can be easily adjusted, thereby changing the axial dimension of the valve needle assembly to effectively offset the dimensional fluctuation of the bellows; then, the valve needle and the adapter sleeve are connected by welding process, which can ensure the connection reliability of the valve needle and the adapter sleeve.

[0006] In this way, the valve needle assembly and the valve seat do not need to be assembled in stages, and can be directly assembled without distinction, which greatly simplifies the installation process. In addition, the material of the adapter sleeve and the valve needle is the same, which is also conducive to ensuring a reliable connection between the two. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 A schematic structural diagram of a specific implementation of a valve device provided in an embodiment of the present invention;

[0008] Figure 2 A schematic structural diagram of a specific implementation of a valve needle assembly provided in an embodiment of the present invention;

[0009] Figure 3 for Figure 2Schematic diagram of the structure of the middle valve stem.

[0010] Figure 1-Figure 3 The reference numerals in the figures are described as follows:

[0011] 1 valve needle assembly, 11 bellows, 12 valve stem, 121 first section, 121a shaft shoulder, 121a-1 second step surface, 122 second section, 122a thick neck, 122b thin neck, 122b-1 guide portion, 13 valve needle, 131 assembly hole, 14 adapter sleeve, 15 gasket;

[0012] 2 valve seat;

[0013] 3 Take over. DETAILED DESCRIPTION

[0014] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0015] The words "first", "second", etc. mentioned in this article are only for the convenience of describing two or more structures or components with the same or similar structures and / or functions, and do not imply any special limitation on the order and / or importance.

[0016] Please refer to Figure 1-Figure 3 , Figure 1 A schematic structural diagram of a specific implementation of a valve device provided in an embodiment of the present invention. Figure 2 A schematic structural diagram of a specific implementation of a valve needle assembly provided in an embodiment of the present invention. Figure 3 for Figure 2 Schematic diagram of the structure of the middle valve stem.

[0017] The present invention provides a valve device, which can be specifically used in scenes such as variable frequency air conditioning systems and refrigerators to realize the on-off of a fluid medium or the flow regulation of a fluid medium.

[0018] like Figure 1 As shown, the valve device includes a valve needle assembly 1 and a valve seat 2. The valve seat 2 is provided with a valve cavity and two interfaces (not marked in the figure) connected to the valve cavity, and both interfaces can be configured with a connecting pipe 3; the valve seat 2 is also provided with a valve port portion, and the valve port portion is formed with a valve port for connecting the two connecting pipes 3. The valve needle assembly 1 can be completely or partially located in the valve seat 2, and can be displaced under the action of an external driving force to close or open the valve port, thereby realizing the switching between the open valve state and the closed valve state; and, in the open valve state, the opening degree of the valve port can also be different according to the stroke position of the valve needle assembly 1.

[0019] Combination Figure 2 and Figure 3The valve needle assembly 1 includes a bellows 11, a valve stem 12, a valve needle 13 and a gasket 15. The valve stem 12 includes a first section 121 and a second section 122. The bellows 11 can be sleeved on the first section 121, and one end of the bellows 11 can be fixedly connected to the valve stem 12, and the other end can be fixedly connected to the gasket 15. The gasket 15 can be fixed to the valve seat 2 to fix the position of the other end of the bellows 11. The valve needle 13 can be installed on the valve stem 12, specifically, it can be located at the second section 122 of the valve stem 12.

[0020] During specific use, an external driving force can be applied to the valve stem 12 to control the valve needle 13 to move toward the valve mouth through the valve stem 12 until the valve needle 13 can block the valve mouth, thereby achieving valve closing; when the valve needs to be opened, the external driving force can be released, and then under the action of the pipeline pressure and the bellows 11, the valve needle 13 can move away from the valve mouth, thereby achieving valve opening.

[0021] Here, the embodiment of the present invention does not limit the type of external driving force, and the type of valve device may also be different according to the type of external driving force. For example, the external driving force may be manual force, in which case the valve device may be a manual valve device; or, the external driving force may be electric force, in which case the valve device may be an electric valve device, such as an electronic expansion valve. Taking the electric valve device as an example, when in use, a drive assembly may also be configured, and the drive assembly may include a motor and a transmission mechanism for applying an external driving force to the valve stem 12 to displace toward the valve mouth; here, the embodiment of the present invention does not limit the specific structure of the transmission mechanism, and in actual applications, those skilled in the art may design it according to specific needs, as long as the corresponding technical effects can be achieved.

[0022] In the above-mentioned valve device, the key to the normal operation of the product is that the valve needle 13 can return to the specified position under the contraction of the bellows 11. Otherwise, if the pipeline pressure is insufficient, the product will not be able to continue to open the valve and the product will fail. Therefore, how to achieve reliable assembly of the valve needle assembly 1 in the valve seat 2 has become a difficult problem that troubles technicians in this field.

[0023] In addition, the bellows 11 is an elastic part. Compared with machined parts such as the valve stem 12 and the valve needle 13, the size consistency of the bellows 11 is poor, which will also cause the axial size of the valve needle assembly 1 to fluctuate. In view of this, in order to meet the normal opening of the valve device, the conventional solution is generally to divide the valve needle assembly 1 according to the axial size, and then produce the valve seat 2 specifically, which brings difficulties to the design and processing of the valve seat 2.

[0024] To this end, the embodiment of the present invention provides a valve needle assembly 1, which, in addition to the bellows 11, valve stem 12 and valve needle 13, may also include an adapter sleeve 14. The adapter sleeve 14 is installed on the second section 122, and the adapter sleeve 14 and the valve needle 13 are made of the same material. The valve needle 13 is provided with an assembly hole 131, and the outer diameter of the adapter sleeve 14 is smaller than the inner diameter of the assembly hole 131. The adapter sleeve 14 is inserted into the assembly hole 131, and the valve needle 13 and the adapter sleeve 14 are welded and fixed.

[0025] By adopting this scheme, since the outer diameter of the adapter sleeve 14 is smaller than the inner diameter of the assembly hole 131, there is a clearance fit between the adapter sleeve 14 and the valve needle 13, and the installation position of the valve needle 13 relative to the adapter sleeve 14 can be easily adjusted, thereby changing the axial dimension of the valve needle assembly 1 to effectively offset the dimensional fluctuation of the bellows 11; then, the valve needle 13 and the adapter sleeve 14 are connected by a welding process, and the connection reliability of the valve needle 13 and the adapter sleeve 14 can be ensured.

[0026] In this way, there is no need to adopt graded assembly between the valve needle assembly 1 and the valve seat 2, and direct indiscriminate assembly can be performed, which greatly simplifies the installation process.

[0027] The valve needle 13 will constantly collide and abut against the valve port during use. Therefore, in conventional solutions, the material of the valve needle 13 is different from that of the valve stem 12. Generally speaking, the valve needle 13 is made of a material with high hardness, such as stainless steel. In this way, in order to ensure the reliability of welding, the adapter sleeve 14 and the valve needle 13 can be made of the same material, that is, when the valve needle 13 is made of stainless steel, the adapter sleeve 14 can also be made of stainless steel.

[0028] Furthermore, when the valve needle 13 and the adapter sleeve 14 are both made of stainless steel, the two can be connected by laser welding.

[0029] Since the adapter sleeve 14 and the valve stem 12 are usually made of different materials, the adapter sleeve 14 and the second section 122 can be interference-fitted. In this way, the existing technical solution is less changed, and the valve stem 12 and the bellows 13 can both use the design and connection method in the existing technology, which is more acceptable in the market and more conducive to the promotion and use of the product.

[0030] Typically, the gasket 15, the valve stem 12 and the bellows 11 can all be made of copper alloy, and can be fixedly connected and sealed to each other by soldering.

[0031] It should be noted that the above-mentioned scheme of interference fitting the adapter sleeve 14 and the valve stem 12 is only for facilitating the connection between the adapter sleeve 14 and the valve stem 12 when they are made of different materials. However, this does not mean that the adapter sleeve 14 and the valve stem 12 must be made of different materials. In fact, the same material can also be used for the adapter sleeve 14 and the valve stem 12. In this case, the valve stem 12 and the valve needle 13 are made of the same material, and the adapter sleeve 14 can be omitted. Then, the valve stem 12 and the valve needle 13 can be directly clearance-fitted and then welded.

[0032] Please continue to refer to Figure 3 , along the direction away from the first section 121, the second section 122 may include a thick neck 122a and a thin neck 122b, with a first step surface 122c formed therebetween. The adapter sleeve 14 may be interference fitted with the thin neck 122b, and the adapter sleeve 14 may also abut against the first step surface 122c along the axial direction. The first step surface 122c is equivalent to a limiting surface, which can conveniently limit the installation position of the adapter sleeve 14 on the valve stem 12.

[0033] Furthermore, the end of the second section 122 away from the first section 121 may be a guide portion 122 b - 1 for guiding the assembly of the second section 122 and the adapter sleeve 14 to facilitate the assembly of the adapter sleeve 14 and the second section 122 .

[0034] In the assembled state, the adapter sleeve 14 may only partially extend into the assembly hole 131, that is, the adapter sleeve 14 may have a portion extending out of the assembly hole 131. In this way, it can be conveniently ensured that the adapter sleeve 14 and the valve needle 13 are welded.

[0035] The first section 121 may be provided with a shoulder 121a, and the shoulder 121a has a second step surface 121a-1 connected to the second section 122. One end of the bellows 11 may be fitted with the second step surface 121a-1 and can be connected to the second step surface 121a-1. The specific connection method may be a welding process, such as the aforementioned soldering process.

[0036] The above are only preferred embodiments of the present invention. It should be pointed out that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A valve needle assembly, comprising a bellows (11), a valve stem (12) and a valve needle (13), wherein the valve stem (12) comprises a first section (121) and a second section (122), the bellows (11) is sheathed around the first section (121) and is fixedly connected to the valve stem (12), characterized in that: It also includes an adapter sleeve (14), the adapter sleeve (14) is mounted on the second section (122), the valve needle (13) is provided with an assembly hole (131), the outer diameter of the adapter sleeve (14) is smaller than the inner diameter of the assembly hole (131), the adapter sleeve (14) is at least partially located in the assembly hole (131), and the valve needle (13) and the adapter sleeve (14) are welded and fixed; Along a direction away from the first section (121), the second section (122) comprises a thick neck portion (122a) and a thin neck portion (122b), a first step surface (122c) being formed between the two, and the adapter sleeve (14) is mounted on the thin neck portion (122b) and abuts against the first step surface (122c) along the axial direction; The first section (121) is provided with a shaft shoulder (121a), the shaft shoulder (121a) having a second step surface (121a-1) connected to the second section (122), and one end of the bellows (11) is in contact with the second step surface (121a-1) and can be connected to the second step surface (121a-1).

2. The valve needle assembly according to claim 1, characterized in that: The valve needle (13) and the adapter sleeve (14) are both made of stainless steel.

3. The valve needle assembly according to claim 2, characterized in that: The valve needle (13) and the adapter sleeve (14) are connected by laser welding.

4. The valve needle assembly according to any one of claims 1 to 3, characterized in that: The adapter sleeve (14) and the second section (122) are interference fitted.

5. The valve needle assembly according to claim 4, characterized in that: The end of the second section (122) away from the first section (121) is a guide portion (122b-1) used for guiding the assembly of the second section (122) and the adapter sleeve (14).

6. The valve needle assembly according to any one of claims 1 to 3, characterized in that: In the assembled state, the adapter sleeve (14) partially extends into the assembly hole (131).

7. The valve needle assembly according to any one of claims 1 to 3, characterized in that: It also includes a gasket (15), one end of the bellows (11) is fixed to the first section (121), and the other end of the bellows (11) is fixed to the gasket (15).

8. A valve device, comprising a valve needle assembly (1) and a valve seat (2), characterized in that: The valve needle assembly (1) is the valve needle assembly according to any one of claims 1 to 7.

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