Valve needle assembly and valve device

Abstract

The valve needle assembly comprises a corrugated pipe, a valve rod, a valve needle and a reducing sleeve, the valve needle is provided with an assembly hole, at least part of the reducing sleeve is located in the assembly hole, the reducing sleeve is in press fit with the valve needle, the valve rod comprises a first section and a second section, the second section protrudes downwards from the first section, and the corrugated pipe is arranged on the periphery of the first section in a sleeving mode. The second section comprises a connecting part, the reducing sleeve is located on the periphery of the connecting part, and the reducing sleeve and the valve rod are fixed through welding.

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, a valve needle and an adapter sleeve, the valve needle is provided with an assembly hole, the adapter sleeve is at least partially located in the assembly hole, the adapter sleeve is press-fitted with the valve needle, the valve stem includes a first section and a second section, the second section protrudes downward from the first section, the bellows is fixedly connected to the first section, the second section includes a connecting portion, the adapter sleeve is sleeved on the outer periphery of the connecting portion, and the adapter sleeve is welded and fixed to the connecting portion.

[0005] It 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. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1 A schematic structural diagram of a specific implementation of a valve device provided in an embodiment of the present invention;

[0007] Figure 2 A schematic structural diagram of a specific implementation of a valve needle assembly provided in an embodiment of the present invention;

[0008] Figure 3 for Figure 2 Schematic diagram of the structure of the middle valve stem.

[0009] Figure 1-Figure 3 The reference numerals in the figures are described as follows:

[0010] 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 lower guide portion, 13 valve needle, 131 assembly hole, 14 adapter sleeve, 15 gasket;

[0011] 2 valve seat;

[0012] 3 Take over. DETAILED DESCRIPTION

[0013] 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.

[0014] 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.

[0015] 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.

[0016] 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.

[0017] 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.

[0018] 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.

[0019] 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.

[0020] 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.

[0021] 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.

[0022] 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.

[0023] To this end, an embodiment of the present invention provides a valve needle assembly 1, which, in addition to the above-mentioned bellows 11, valve stem 12 and valve needle 13, may also include an adapter sleeve 14. The valve needle 13 is provided with an assembly hole 131. The adapter sleeve 14 is at least partially located in the assembly hole 131. The adapter sleeve 14 can be made of the same material as the valve needle 13, such as stainless steel. The valve needle 13 and the adapter sleeve 14 are press-fitted to form a whole.

[0024] With this solution, since the outer diameter of the adapter sleeve 14 is smaller than the inner diameter of the assembly hole 131, the adapter sleeve 14 and the valve needle 13 are tightly fitted, and the valve needle component provided with the adapter sleeve can be axially moved relative to the valve stem 12. The adapter sleeve 14 and the valve stem 12 are slidingly guided, and a preset small gap is provided between the inner circumferential wall of the adapter sleeve and the outer circumferential wall of the valve stem. After the overall height of the valve needle assembly is limited according to the tooling, the adapter sleeve and the valve stem are welded and fixed. For example, in this embodiment, laser welding and fixing can be adopted, which is more convenient. Through the above design, the installation position of the valve needle 13 provided with the adapter sleeve relative to the valve stem 12 can be conveniently adjusted, and then the axial dimension of the valve needle assembly 1 can be changed to effectively offset the dimensional fluctuation of the bellows 11; then, the valve stem 12 and the adapter sleeve 14 are connected by welding process, and the connection reliability of the valve stem 12 and the adapter sleeve 14 can be guaranteed.

[0025] 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.

[0026] 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, the thin neck 122b is a connecting portion, and a first step surface 122c is formed between the thick neck 122a and the connecting portion. During the assembly process, the adapter sleeve 14 can be slidably guided with the connecting portion and then the two are welded and fixed. For example, when the valve needle height is just adjusted to the height specified by the tooling, the adapter sleeve 14 can also be axially abutted against the first step surface 122c. 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.

[0027] Furthermore, the end of the second section 122 away from the first section 121 can be a lower guide portion 122b-1, which is used to guide 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. The connecting portion includes an upper guide portion and a lower guide portion 122b-1. The gap value between the lower guide portion 122b-1 and the inner circumferential wall of the adapter sleeve 14 is greater than the gap value between the upper guide portion and the inner circumferential wall of the connecting sleeve 14. This can facilitate the assembly of the adapter sleeve and the valve stem.

[0028] 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, or the adapter sleeve 14 may be entirely located in the assembly hole 131, that is, the adapter sleeve 14 is at least partially located in the assembly hole 131. In this embodiment, the adapter sleeve 14 may protrude from the assembly hole 131 to increase the sliding guide fitting length when assembled with the valve stem.

[0029] The first section 121 of the valve stem 12 can 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 can be fitted with the second step surface 121a-1 and can be connected to the second step surface 121a-1. The specific connection method can be a welding process, such as the aforementioned soldering process.

[0030] 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, characterized in that: It includes a bellows, a valve stem, a valve needle and an adapter sleeve, the valve needle is provided with an assembly hole, the adapter sleeve is at least partially located in the assembly hole, the adapter sleeve is press-fitted with the valve needle, the valve stem includes a first section and a second section, the second section protrudes downward from the first section, the bellows is fixedly connected to the first section, the second section includes a connecting portion, the adapter sleeve is sleeved on the outer periphery of the connecting portion, and the adapter sleeve is welded and fixed to the connecting portion.

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

3. The valve needle assembly according to claim 1, characterized in that: There is a preset gap between the inner peripheral wall of the adapter sleeve and the outer peripheral arm of the connecting portion.

4. The valve needle assembly according to claim 1, characterized in that: Along the direction away from the first section, the second section includes a thick neck and a thin neck, a first step surface is formed between the two, and the thin diameter portion is the connecting portion.

5. The valve needle assembly according to claim 4, characterized in that: The outer diameter of the thin neck is smaller than the outer diameter of the thick neck.

6. The valve needle assembly according to claim 1, characterized in that: In the assembled state, the valve needle provided with the adapter sleeve can be axially displaced relative to the valve stem, and the adapter sleeve is slidably guided in cooperation with the connecting portion.

7. The valve needle assembly according to any one of claims 1 to 6, characterized in that: It also includes a gasket, one end of the bellows is fixed to the first section, and the other end of the bellows is fixed to the gasket.

8. The valve needle assembly according to any one of claims 1 to 6, characterized in that: The connecting portion includes an upper guiding portion and a lower guiding portion, and a preset gap value between the lower guiding portion and the adapter sleeve is greater than a preset gap value between the upper guiding portion and the adapter sleeve.

9. A valve device, characterized in that: It includes a valve seat and a valve needle assembly, the valve seat is provided with a valve mouth portion, the valve needle can approach or move away from the valve mouth portion, the valve device is provided with a accommodating cavity, the bellows is at least partially located in the accommodating cavity, the valve needle assembly includes a gasket, the gasket is fixedly connected to the valve seat, and the valve needle assembly is the valve needle assembly according to any one of claims 1-6.

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