Valve seat assembly, machining method thereof, welding tool and electronic expansion valve

Abstract

The invention discloses a valve seat assembly and a machining method thereof, a welding tool and an electronic expansion valve, the valve seat assembly comprises a valve seat and a connecting pipe, the valve seat is provided with a valve seat hole, the connecting pipe is provided with a connecting end, the connecting end is at least partially inserted into the valve seat hole and abuts against the valve seat hole, and an intersection matching part is formed between the connecting end and the valve seat hole; and the intersection matching part is pre-fixed through laser welding and is at least partially filled with the molten welding flux. According to the valve seat assembly, before the intersection matching part between the connecting end and the valve seat hole is sealed, pre-fixing is conducted through laser welding, the positioning size of all parts is not guaranteed through a welding tool, the tool structure can be simplified, the design and machining difficulty is lowered, the weight of the tool is reduced, the number of weldable products in the unit area is increased, and the welding efficiency is improved; meanwhile, after the valve seat and the connecting pipe are fixedly connected, the situation of external leakage caused by tool deformation or part size out-of-tolerance can be avoided, and the welding quality is improved; as the valve seat and the connecting pipe are pre-fixed, the welding process can be automatically operated, and the labor cost is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of refrigeration control, and particularly relates to a valve seat assembly, a processing method thereof, a welding tooling, and an electronic expansion valve. Background Art

[0002] The valve seat assembly of a valve device generally includes a valve seat and a connecting pipe. The valve seat has a valve seat hole for connecting the connecting pipe. Generally, the end head of the connecting pipe is first placed inside the valve seat hole of the valve seat, and the two are in clearance fit. Then, a welding ring sleeved on the outer peripheral part of the connecting pipe is adjusted to a predetermined position for welding to achieve the fixation and sealing between the valve seat and the connecting pipe. For those skilled in the art, it is necessary to ensure the welding reliability between the valve seat and the connecting pipe as much as possible. Summary of the Invention

[0003] The purpose of the present invention is to provide a valve seat assembly, a processing method thereof, a welding tooling, and an electronic expansion valve to ensure the welding quality.

[0004] To solve the above technical problems, the present invention provides a valve seat assembly, including a valve seat and a connecting pipe. The valve seat has a valve seat hole, and the connecting pipe has a connecting end. The connecting end is at least partially inserted into the valve seat hole and abuts against it. A converging mating part is formed between the connecting end and the valve seat hole. The converging mating part is pre-fixed by laser welding and at least partially filled with the melted solder.

[0005] The present invention also provides an electronic expansion valve, including a valve seat assembly, a lead screw component, and a valve needle component. The valve seat component has a valve port part. The lead screw component can drive the valve needle component to move along the axis direction of the valve seat component to approach or away from the valve port part. The valve seat assembly is the aforementioned valve seat assembly.

[0006] The present invention also provides a processing method of a valve seat assembly, which is applicable to the aforementioned valve seat assembly, and includes the following steps:

[0007] Step S1: Clamp the welding ring on the connecting end of the connecting pipe, and at least partially insert the connecting end into the valve seat hole of the valve seat and make the two abut against each other;

[0008] Step S2: Fix the converging mating part of the connecting end and the valve seat hole by laser welding, and then push the welding ring towards the valve seat;

[0009] Step S3: Melt the welding ring by furnace welding, and at least partially fill the converging mating part of the connecting end and the valve seat hole with the melted solder.

[0010] The present invention also provides a welding tooling for a valve seat assembly, which is used to process the aforementioned valve seat assembly. The welding tooling includes a base, and positioning part groups are arranged at both ends of the upper side wall of the base in a first direction. The positioning part groups include one or more positioning parts, and a plurality of the positioning parts are spaced along a second direction, and each of the positioning parts is staggered with each other along the second direction.

[0011] The welding tooling further includes a partition plate, which is connected to the upper side wall of the base. The partition plate is located between the two positioning part groups, and the partition plate extends along the second direction. Avoidance holes are arranged at positions corresponding to each of the positioning parts, and the first direction and the second direction are perpendicular to each other.

[0012] The technical effects of the present invention are as follows:

[0013] Before sealing the intersection and mating part of the connecting end and the valve seat hole, the present invention first pre-fixes them by laser welding. The positioning dimensions do not need to be guaranteed by the welding tooling. Therefore, the structure of the welding tooling can be simplified, the design and processing difficulty of the welding tooling can be reduced, the weight of the welding tooling can be reduced, the proportion occupied by the welding tooling can be reduced, the number of weldable products per unit area can be increased, the welding efficiency can be improved, and the welding cost can be reduced. At the same time, after the valve seat and the connecting pipe are pre-fixed, external leakage caused by deformation of the welding tooling or out-of-tolerance of part dimensions can be avoided, and the welding quality can be improved. Since the valve seat and the connecting pipe are pre-fixed, the subsequent welding process can be automated, reducing labor costs. Description of the Drawings

[0014] Figure 1 is an exploded view of a specific embodiment of the valve seat assembly provided by the present invention;

[0015] Figure 2 is Figure 1 the first state diagram of the valve seat assembly during the assembly process;

[0016] Figure 3 is Figure 1 the second state diagram of the valve seat assembly during the assembly process;

[0017] Figure 4 is Figure 3 a partial enlarged view of;

[0018] Figure 5 is Figure 1 the third state diagram of the valve seat assembly during the assembly process;

[0019] Figure 6 is Figure 1 the axial sectional view of the first specific embodiment of the valve seat in the valve seat assembly;

[0020] Figure 7 is Figure 6 the sectional view of the connection between the valve seat and the connecting pipe;

[0021] Figure 8 is Figure 1 An axial sectional view of the second specific embodiment of the valve seat in the valve seat assembly;

[0022] Figure 9 is Figure 8 A sectional view of the connection between the valve seat and the nozzle;

[0023] Figure 10 A schematic structural view of a specific embodiment of the welding tooling for the valve seat assembly provided by the present invention;

[0024] Figure 11 is Figure 10 A working state diagram of the welding tooling for the valve seat assembly;

[0025] Wherein, Figures 1 - 11 The reference numerals in are explained as follows:

[0026] A - valve seat assembly; 1 - valve seat; 1a - valve seat hole; 1b - step surface; 2 - nozzle; 21 - connection end; 211 - thin section; 212 - transition section; 213 - thick section; 3 - welding ring;

[0027] 01 - base; 02 - positioning part group; 021 - positioning part; 03 - partition; 03a - avoidance hole. Specific embodiments

[0028] In order to enable those skilled in the art to better understand the technical solutions of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0029] As used herein, "a plurality of" generally means more than two; and when "a plurality of" is used to represent the quantity of several components, it does not represent the mutual relationship in quantity of these components.

[0030] Please refer to Figures 1 - 5 , Figure 1 A split view of a specific embodiment of the valve seat assembly provided by the present invention; Figure 2 is Figure 1 A first state diagram of the valve seat assembly during the assembly process; Figure 3 is Figure 1 A second state diagram of the valve seat assembly during the assembly process; Figure 4 is Figure 3 A partial enlarged view of; Figure 5 is Figure 1 A third state diagram of the valve seat assembly during the assembly process.

[0031] The present invention provides a valve seat assembly, which includes a valve seat 1 and a connecting pipe 2. The valve seat 1 has a valve seat hole 1a, and the connecting pipe 2 has a connecting end 21. The connecting end 21 is at least partially inserted into the valve seat hole 1a and abuts against it. A converging mating part is formed between the connecting end 21 and the valve seat hole 1a. The converging mating part is pre-fixed by laser welding and at least partially filled with the melted solder.

[0032] Before sealing the converging mating part between the connecting end 21 and the valve seat hole 1a of the valve seat assembly of the present invention, it is first pre-fixed by laser welding to ensure the reliable relative position of the two. The positioning dimensions of each component no longer rely on the welding fixture to ensure. Therefore, the structure of the welding fixture can be simplified, the design and processing difficulty of the welding fixture can be reduced, the weight of the welding fixture can be reduced at the same time, the proportion occupied by the welding fixture can be reduced, the number of weldable products per unit area can be increased, the welding efficiency can be improved, and the welding cost can be reduced. At the same time, after the valve seat 1 and the connecting pipe 2 are pre-fixed by laser welding, the external leakage caused by the deformation of the welding fixture or the dimensional tolerance of the components can be avoided, and the welding quality can be improved. In addition, precisely because the valve seat 1 and the connecting pipe 2 are pre-fixed by laser welding, the subsequent welding process can be automated, reducing labor costs.

[0033] It can be seen that Figures 1 - 5 in this embodiment, the converging mating part between the connecting end 21 and the valve seat hole 1a is sealed by brazing. Specifically, the welding ring 3 is melted and filled in at least part of the area of the converging mating part. During the assembly process of the valve seat assembly, the welding ring 3 can be first clamped on the connecting end 21 of the connecting pipe 2, the connecting end 21 is at least partially inserted into the valve seat hole 1a of the valve seat 1, and the welding ring 3 is arranged away from the wall of the valve seat 1 where the valve seat hole 1a is located to avoid interference of the welding ring 3 on the subsequent spot welding operation. Then, the converging mating part between the connecting end 21 and the valve seat hole 1a is pre-fixed by laser welding, and then the welding ring 3 is pushed towards the valve seat 1 so that the welding ring 3 fits against the wall of the valve seat 1 where the valve seat hole 1a is located. Finally, the welding ring 3 is melted by brazing technology and filled in at least part of the area of the converging mating part.

[0034] Among them, it can be seen that Figure 4 and Figure 5 in this embodiment, the welding ring 3 is annular and axially disconnected, so that the welding ring 3 has a certain amount of deformation, which is convenient for sleeving the welding ring 3 on the connecting end 21.

[0035] Please refer to Figures 6 - 7 , Figure 6 which is Figure 1 the axial sectional view of the first specific embodiment of the valve seat in the valve seat assembly; Figure 7 and Figure 6 the sectional view of the connection between the valve seat and the connecting pipe.

[0036] In this embodiment, the connecting end 21 includes a thin section 211, a transition section 212, and a thick section 213 that are sequentially connected along the axis. The thin section 211 is close to the free end of the connecting pipe 2. The thin section 211 is inserted into the valve seat hole 1a. The valve seat 1 is provided such that the wall of the valve seat hole 1a abuts against the outer peripheral wall of the transition section 212, thereby achieving the abutment between the connecting end 21 and the valve seat hole 1a.

[0037] Please refer to Figures 8 - 9 , Figure 8 which is Figure 1 the axial sectional view of the second specific embodiment of the valve seat in the valve seat assembly; Figure 9 and Figure 8 the sectional view of the connection between the valve seat and the connecting pipe.

[0038] In this embodiment, the valve seat hole 1a includes a small-diameter section and a large-diameter section that are axially connected. The large-diameter section is close to the outer end of the valve seat 1. A stepped surface 1b facing the outer end is formed between the small-diameter section and the large-diameter section. At least a part of the connecting end 21 is inserted into the valve seat hole 1a, and the inner end wall of the connecting end 21 abuts against the stepped surface 1b, thereby achieving the abutment between the connecting end 21 and the valve seat hole 1a.

[0039] The present invention also provides an electronic expansion valve, which includes a valve seat assembly, a lead screw component, and a valve needle component. The valve seat component has a valve port portion. The lead screw component can drive the valve needle component to move along the axis of the valve seat component to approach or move away from the valve port portion. The valve seat assembly is the aforementioned valve seat assembly.

[0040] The electronic expansion valve of the present invention includes the aforementioned valve seat assembly, and thus has the same technical effects as the aforementioned valve seat assembly, which will not be elaborated herein.

[0041] The present invention also provides a processing method for a valve seat assembly, which is applicable to the aforementioned valve seat assembly and includes the following steps:

[0042] Step S1: Clamp the welding ring 3 on the connecting end 21 of the connecting pipe 2, insert at least a part of the connecting end 21 into the valve seat hole 1a of the valve seat 1 and make the two abut;

[0043] Step S2: Pre-fix the intersection mating portion of the connecting end 21 and the valve seat hole 1a by laser welding, and then push the welding ring 3 towards the valve seat 1;

[0044] Step S3: The welding ring 3 is melted by furnace welding, and at least a part of the intersection mating portion of the connecting end 21 and the valve seat hole 1a is filled with the melted solder.

[0045] The processing method of the valve seat assembly of the present invention is applicable to the aforementioned valve seat assembly, and thus has the same technical effects as the aforementioned valve seat assembly, which will not be elaborated herein.

[0046] Among them, in step S2, in order to ensure the reliable connection between the connection end 21 and the valve seat hole 1a, laser welding pre-fixing can be performed on both radial sides of the connection end 21.

[0047] Among them, as described above, in Figure 6 and Figure 7 In the embodiments of, the connection end 21 includes a thin section 211, a transition section 212, and a thick section 213 that are sequentially connected along the axial direction. The thin section 211 is close to the free end of the connecting pipe 2. In step S1, at least a part of the connection end 21 is inserted into the valve seat hole 1a of the valve seat 1 and the two are abutted, including the following steps:

[0048] Insert the thin section 211 into the valve seat hole 1a, and make the wall of the valve seat 1 provided with the valve seat hole 1a and the outer peripheral wall of the transition section 212 abut and limit.

[0049] Among them, as described above, in Figure 8 and Figure 9 In the embodiments of, the valve seat hole 1a includes a small-diameter section and a large-diameter section that are axially connected. The large-diameter section is close to the outer end of the valve seat 1. A step surface 1b facing the outer end is formed between the small-diameter section and the large-diameter section. In step S1, at least a part of the connection end 21 is inserted into the valve seat hole 1a of the valve seat 1 and the two are abutted, including the following steps:

[0050] Partially insert the connection end 21 into the valve seat hole 1a, and make the inner end wall of the connection end 21 abut against the step surface 1b.

[0051] In addition, in step S1, there is a spacing between the wall of the valve seat 1 provided with the valve seat hole 1a and the welding ring 3, and the value range of the spacing is 10mm - 20mm.

[0052] Of course, this numerical limitation is only for illustrative purposes, and in practice, it can be adjusted adaptively as long as the welding ring 3 is prevented from interfering with the laser welding pre-fixing operation.

[0053] Please refer to Figures 10 - 11 , Figure 10 is a schematic structural diagram of a specific embodiment of the welding tooling for the valve seat assembly provided by the present invention; Figure 11 is Figure 10 a working state diagram of the welding tooling for the valve seat assembly.

[0054] The present invention also provides a welding tooling for a valve seat assembly, which is used to process the aforementioned valve seat assembly A, including a base 01. Positioning part groups 02 are provided at both ends of the upper side wall of the base 01 in the first direction. The positioning part groups 02 include a plurality of positioning parts 021. The plurality of positioning parts 021 are spaced apart along the second direction, and each positioning part 021 is staggered with each other along the second direction.

[0055] It further includes a partition plate 03. The partition plate 03 is connected to the upper side wall of the base 01. The partition plate 03 is located between the two positioning part groups 02. The partition plate 03 extends along the second direction. The partition plate 03 is provided with avoidance holes 03a at positions corresponding to each positioning part 021. The first direction and the second direction are perpendicular to each other.

[0056] The welding tooling for the valve seat assembly of the present invention is used to process the aforementioned valve seat assembly A, so it has the same technical effects as the aforementioned valve seat assembly A, which will not be elaborated here.

[0057] In this embodiment, the positioning part group 02 includes a plurality of positioning parts 021. In practice, the number of positioning parts 021 provided in each positioning part group 02 can be at least one.

[0058] Among them, as Figure 10 and Figure 11 shown, in this embodiment, the positioning part 021 is a positioning protrusion, and the positioning protrusion is used for insertion and fitting with the valve cavity of the valve seat 1.

[0059] Of course, in practice, the specific structure of the positioning part 021 is not limited. For example, the positioning part 021 can also be a hole-like structure. During welding, a part of the valve seat 1 is inserted into the hole-like positioning part 021 to achieve fixation.

[0060] The above has introduced in detail a valve seat assembly, its processing method, welding tooling and valve provided by the present invention. Specific examples are used in this article to elaborate on the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

1. A valve seat assembly, characterized in that, It includes a valve seat (1) and a connecting pipe (2). The valve seat (1) has a valve seat hole (1a), and the connecting pipe (2) has a connecting end (21). The connecting end (21) is at least partially inserted into the valve seat hole (1a) and abuts against it. A converging mating part is formed between the connecting end (21) and the valve seat hole (1a), and the converging mating part is pre-fixed by laser welding and at least partially filled with the melted solder.

2. The valve seat assembly according to claim 1, wherein The connecting end (21) includes a thin section (211), a transition section (212), and a thick section (213) connected in sequence along the axial direction. The thin section (211) is close to the free end of the connecting pipe (2). The thin section (211) is inserted into the valve seat hole (1a), and the wall of the valve seat (1) where the valve seat hole (1a) is provided abuts against the outer peripheral wall of the transition section (212).

3. The valve seat assembly according to claim 1, wherein, The valve seat hole (1a) includes a small-diameter section and a large-diameter section connected axially. The large-diameter section is close to the outer end of the valve seat (1). A stepped surface (1b) facing the outer end is formed between the small-diameter section and the large-diameter section. The connecting end (21) is at least partially inserted into the valve seat hole (1a), and the inner end wall of the connecting end (21) abuts against the stepped surface (1b).

4. An electronic expansion valve, comprising a valve seat assembly, a lead screw component and a valve needle component, wherein the valve seat component has a valve port portion, and the lead screw component can drive the valve needle component to move along the axial direction of the valve seat component to approach or move away from the valve port portion, characterized in that, The valve seat assembly is the valve seat assembly according to any one of claims 1-3.

5. A processing method for a valve seat assembly, applicable to the valve seat assembly according to any one of claims 1-3, characterized in that, It includes the following steps: Step S1: Clamp the welding ring (3) on the connecting end (21) of the connecting pipe (2), and at least partially insert the connecting end (21) into the valve seat hole (1a) of the valve seat (1) and make the two abut against each other; Step S2: Pre-fix the converging mating part of the connecting end (21) and the valve seat hole (1a) by laser welding, and then push the welding ring (3) in the direction of the valve seat (1); Step S3: Melt the welding ring (3) by furnace welding, and at least partially fill the converging mating part of the connecting end (21) and the valve seat hole (1a) with the melted solder.

6. The processing method of the valve seat assembly according to claim 5, characterized in that, The connecting end (21) includes a thin section (211), a transition section (212), and a thick section (213) connected in sequence along the axial direction. The thin section (211) is close to the free end of the connecting pipe (2). In step S1, at least partially inserting the connecting end (21) into the valve seat hole (1a) of the valve seat (1) and making the two abut against each other includes the following steps: Insert the thin section (211) into the valve seat hole (1a), and make the wall of the valve seat (1) where the valve seat hole (1a) is provided abut against the outer peripheral wall of the transition section (212).

7. The processing method of the valve seat assembly according to claim 5, characterized in that, The valve seat hole (1a) includes a small-diameter section and a large-diameter section connected axially. The large-diameter section is close to the outer end of the valve seat (1). A stepped surface (1b) facing the outer end is formed between the small-diameter section and the large-diameter section. In step S1, at least partially inserting the connecting end (21) into the valve seat hole (1a) of the valve seat (1) and making the two abut against each other includes the following steps: Partially insert the connecting end (21) into the valve seat hole (1a), and make the inner end wall of the connecting end (21) abut against the stepped surface (1b).

8. The processing method of the valve seat assembly according to claim 5, characterized in that, In the step S1, there is a spacing between the wall of the valve seat hole (1a) provided on the valve seat (1) and the welding ring (3), and the value range of the spacing is 10 mm - 20 mm.

9. A welding tooling for a valve seat assembly, which is used for machining the valve seat assembly according to any one of claims 1-3, characterized in that, It includes a base (01), and positioning part groups (02) are provided at both ends of the upper side wall of the base (01) in the first direction. The positioning part groups (02) include one or more positioning parts (021), and a plurality of the positioning parts (021) are spaced apart along the second direction, and the positioning parts (021) are staggered with each other along the second direction. It further includes a partition plate (03), the partition plate (03) is connected to the upper side wall of the base (01), the partition plate (03) is located between the two positioning part groups (02), the partition plate (03) extends along the second direction, and avoidance holes (03a) are provided at positions corresponding to each of the positioning parts (021), and the first direction and the second direction are perpendicular to each other.

10. The welding tooling for the valve seat assembly according to claim 9, characterized in that, The positioning part (021) is a positioning protrusion, and the positioning protrusion is used for insertion and fitting with the valve cavity of the valve seat (1).

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