CN117662770A

CN117662770A - Valve needle assembly, valve device, processing method and processing device of valve needle assembly

Info

Publication number: CN117662770A
Application number: CN202211057570.5A
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: 2022-08-31
Filing date: 2022-08-31
Publication date: 2024-03-08

Abstract

The application discloses processing method and processing device of needle subassembly, valve device, needle subassembly, the needle subassembly includes bellows, valve rod, gasket and needle, the bellows suit is in the valve rod periphery, the one end of bellows with the gasket is soldered, the other end with the valve rod is soldered, the valve rod is kept away from the one end of gasket stretches out the bellows, the needle interference press sleeve is in the valve rod is kept away from the one end periphery of gasket and with the valve rod is kept away from the one end terminal surface conflict of gasket, the valve rod is kept away from the one end terminal surface of gasket is the turn-milling machined surface. The length uniformity that this application can promote the needle subassembly has avoided leading to production efficiency low and valve device aperture can not satisfy the problem of design requirement because of the length uniformity of needle subassembly is not good.

Description

Valve needle assembly, valve device, processing method and processing device of valve needle assembly

Technical Field

The application relates to the technical field of valve devices, in particular to a valve needle assembly, a valve device adopting the valve needle assembly, and a processing method and a processing device of the valve needle assembly.

Background

The valve needle subassembly and the valve body are the important constitution of valve device, and the valve needle subassembly is assembled in the installation cavity of valve body, and the length of valve needle subassembly and the length of valve body installation cavity are related to the aperture of valve device, if the length uniformity of valve needle subassembly is not good, then lead to the aperture of valve device to fail to satisfy the design requirement easily, still need carry out the processing of valve body installation cavity after having assembled the length of valve needle subassembly earlier, lead to production efficiency low.

In view of this, how to improve the length uniformity of the valve needle assembly is a technical problem that needs to be solved by those skilled in the art.

Disclosure of Invention

In order to solve the technical problem, the application provides a valve needle assembly, the valve needle assembly includes bellows, valve rod, gasket and valve needle, the bellows suit is in the valve rod periphery, the one end of bellows with the gasket is soldered, the other end with the valve rod is soldered, the valve rod is kept away from the one end of gasket stretches out the bellows, the valve needle interference press sleeve is in the valve rod is kept away from the one end periphery of gasket and with the valve rod is kept away from the one end terminal surface conflict of gasket, the valve rod is kept away from the one end terminal surface of gasket is the milling surface.

Still provide a valve device, including needle subassembly, actuating assembly and valve body, its characterized in that, the needle subassembly is above-mentioned needle subassembly, the valve body is equipped with the installation cavity, the one end of installation cavity is equipped with the valve mouth, the installation cavity is kept away from the one end of valve mouth is equipped with spacing face, the needle subassembly install in the installation cavity, the gasket of needle subassembly be close to the one end terminal surface of needle with spacing face is contradicted, the actuating assembly supports and pushes away the valve rod, makes the valve rod drives the needle is to closing the direction of valve mouth removes.

The invention also provides a processing method of the valve needle assembly, wherein the valve needle assembly is the valve needle assembly, and the processing method comprises the following steps: the assembly is positioned, the assembly comprises a corrugated pipe, a valve rod and a gasket which are assembled together, one end face, close to the valve needle, of the gasket is used as a positioning reference surface, after the positioning is finished, the valve rod is far away from one end face of the gasket, milling is carried out until the distance between the one end face, far away from the gasket, of the valve rod and the one end face, close to the valve needle, of the gasket is equal to a preset value.

The invention also provides a processing device of the valve needle assembly, which is used for realizing the processing method, and comprises the following steps: a positioning component for positioning the assembly and a turning and milling component for turning and milling an end face of the valve rod, which is far away from the gasket.

The length uniformity that this application can promote the needle subassembly has avoided leading to production efficiency low and valve device aperture can not satisfy the problem of design requirement because of the length uniformity of needle subassembly is not good.

Drawings

FIG. 1 is a cross-sectional view of one embodiment of a valve cartridge assembly provided herein;

FIG. 2 is a partial cross-sectional view of a valve apparatus employing the valve cartridge assembly shown in FIG. 1;

FIG. 3 is a schematic view of an embodiment of a processing apparatus for a valve core assembly provided herein;

FIG. 4 is a schematic view showing a state in which an end face of a valve stem is processed by the processing apparatus shown in FIG. 3;

FIG. 5 is an enlarged view of the positioning ram of FIG. 3;

FIG. 6 is an enlarged view of the positioning seat of FIG. 3;

FIG. 7 is an M-M view of FIG. 4;

fig. 8 is a perspective view of a single grip portion of the grip assembly.

The reference numerals are explained as follows:

100 valve core components; 101 corrugated pipe, 101a body part, 101b flanging part and 101c riveting part; 102 valve stem, 102a rivet; 103 gaskets; 104 valve needle; 105 bushings;

200 valve body, 201 mounting cavity, 202 valve port part, 203 limit surface;

300 a drive assembly;

400 processing devices;

401 positioning components, 4011 positioning seats, 4011a top seats, 4011B bases, A through holes, B positioning surfaces, C clamping part mounting holes, C1 top grooves, C2 bottom grooves, D elastic component mounting holes, E pit parts, F sleeve parts and G connecting holes; 4012 positioning pressure head, 4012a connecting hole, 4012b avoiding hole, K pressing surface, 4013 positioning clamp, 4013a clamping part, H pressing surface, I notch part and J bulge;

402 turn-milling assembly, 4021 knife, 4022 knife driving motor, 4023 connecting sleeve.

Detailed Description

In order to make those skilled in the art better understand the technical solutions of the present application, the following further details are given to the technical solutions of the present application by referring to the drawings and the detailed description.

As shown in fig. 1, the valve needle assembly 100 includes a bellows 101, a stem 102, a gasket 103, a valve needle 104, a bushing 105, and the like.

The bellows 101 includes a body portion 101a, and the body portion 101a thereof has a large elasticity, so that the length dimension of the bellows 101 can fluctuate over a large range.

One end of the body portion 101a of the corrugated tube 101 is folded and folded approximately along the length direction of the corrugated tube 101 to form a flanging portion 101b, the gasket 103 is fixedly connected to the end of the corrugated tube 101, specifically, the gasket 103 is provided with a center hole, and the flanging portion 101b of the end of the corrugated tube 101 is inserted into the center hole of the gasket 103 and soldered with the gasket 103, so that the gasket 103 and the corrugated tube 101 are fixedly connected.

The other end of the body 101a of the bellows 101 is folded substantially in the longitudinal direction of the bellows 101, and then folded substantially in the radial direction of the bellows 101 to form a swage portion 101c, and the valve stem 102 is fixed to the end of the bellows 101. Specifically, the bellows 101 is sleeved on the outer periphery of the valve rod 102, the outer periphery of the valve rod 102 is locally protruded outwards along the radial direction to form a riveting part 102a, and the riveting part 102a of the valve rod 102 and the riveting part 101c of the bellows 101 are mutually riveted, limited and soldered, so that the valve rod 102 and the bellows 101 are fixedly connected.

A bushing 105 is installed at one end of the valve rod 102, which is close to the gasket 103, and the bellows 101 extends out of one end of the valve rod 102, which is far away from the gasket 103, and the valve needle 104 is in interference press fit with one end face of the valve rod 102, which is far away from the gasket 103, and is abutted against one end face of the valve rod 102, which is far away from the gasket 103.

The end face of the valve rod 102, which is far away from the gasket 103, is a turning surface, and by turning the end face of the valve rod 102, which is far away from the gasket 103, the axial distance L3 between the end face of the valve rod 102, which is far away from the gasket 103, and the end face of the gasket 103, which is close to the valve needle 104, can be equal to a preset value in a natural state of the bellows 101.

Specifically, bellows 101 is typically a die-drawn shaper, and valve pin 104 is typically a machined part. The corrugated pipe 101 can be made of copper or copper alloy, so that the stamping, drawing and shaping of the corrugated pipe 101 are facilitated. The valve rod 102 and the gasket 103 can also be made of copper or copper alloy, so that the corrugated pipe 101 can be soldered conveniently, and the soldering can ensure the connection reliability of the corrugated pipe 101, the valve rod 102 and the gasket 103. Valve pin 104 may be made of stainless steel, which may ensure strength of the valve pin and facilitate machining of the valve pin.

As shown in fig. 2, when the above-described needle assembly 100 is applied to a valve device, the needle assembly 100 is mounted to the mounting chamber 201 of the valve body 200. One end of the installation cavity 201 of the valve body 200 is provided with a valve opening 202, and one end of the installation cavity 201 away from the valve opening 202 is provided with a limiting surface 203.

The gasket 103 of the valve needle assembly 100 abuts against the limiting surface 203 of the valve body 200 to limit the position near the end surface of the valve needle 104. Valve device driving assembly 300 pushes valve stem 102, specifically, bushing 105 connected to valve stem 102, so that valve stem 102 drives valve needle 104 to move in the direction of closing valve opening 202, and valve opening 202 is completely closed until point X of valve needle 104 abuts against point Y of valve opening 202. During this time, the bellows 101 changes from a natural state to an elongated state, thereby accumulating elastic energy. When the driving force of the driving assembly 300 is removed, the bellows 101 releases elastic energy, and the valve needle 104 and the valve stem 102 are reset to the direction of opening the valve opening 202 under the elastic energy of the bellows 101 and the pressure of medium in the valve, so that the bellows 101 is gradually reset to a natural state.

Opening degree of valve device = axial distance L2 between limit surface 203 of valve body 200 and point Y of valve port 202-axial distance L1 between one end surface of gasket 103 near valve needle 104 and point X of valve needle 104 in natural state of bellows 101. The axial distance between the end face of valve stem 102 away from gasket 103 and the end face of gasket 103 close to valve needle 104 is L3, and the axial distance between the end face of valve needle 104 away from gasket 103 and the end face of gasket 103 close to valve needle 104 is L4, l1=l3+l4.

Because the bellows 101 is a punch-shaped member, the consistency of the axial length is poor, which results in poor consistency of the axial distance L1, so that conventionally, the valve needle assembly 100 needs to be assembled first, then the axial distance L1 is measured, and then the axial distance L2 of the valve body 200 is determined according to the measured axial distance length L1, so that the valve body 200 needs to be machined after the valve needle assembly 100 is assembled, and the production efficiency is affected, otherwise, the opening of the valve device cannot meet the design requirement due to poor consistency of L1.

In this application, the end face of the valve rod 102 far away from the gasket 103 is machined by turning and milling, so that the consistency of L3 is good. In addition, the valve needle 104 is usually a machined part, and has good self consistency, and the valve needle 104 is in interference press fit with the end face of the valve rod 102, which is far away from the gasket 103, and is in interference contact with the end face of the valve rod 102, which is far away from the gasket 103, so that the consistency of L4 is good. Therefore, this application can ensure that length L1 (l1=l3+l4) uniformity is better, adopts this application, need not to wait for the processing of valve body 200 again after valve needle subassembly 100 to assemble, and the processing of valve body 200 and the equipment of valve needle subassembly 100 can go on in step, so production efficiency promotes, and moreover, also be difficult to appear the aperture and can not satisfy the problem of design requirement.

Further, the application also provides a processing method of the valve needle assembly, which comprises the following steps: the assembly is positioned and includes a bellows 101, a valve stem 102, and a gasket 103 assembled together, and may also include a bushing 105. The end face of the gasket 103, which is close to the valve needle 104, is used as a positioning reference surface. After positioning, the end face of the valve rod 102 far away from the gasket 103 is milled until the distance L3 between the end face of the valve rod 102 far away from the gasket 103 and the end face of the gasket 103 near the valve needle 104 is equal to a preset value. After machining, the assembly and valve needle 104 are assembled.

Further, the present application also provides a processing device 400 for implementing the above processing method. As shown in fig. 3, the machining device 400 includes a positioning assembly 401 for positioning the assembly and a turning and milling assembly 402 for turning and milling an end face of the valve stem 102 remote from the gasket 103.

As shown in fig. 3, the positioning assembly 401 includes a positioning seat 4011, a positioning ram 4012, a positioning fixture 4013, and a positioning ram driving device (not shown) and a positioning fixture driving device (not shown). In addition, a resilient return member (not shown) may be included.

The positioning seat 4011 and the positioning ram 4012 cooperate with the gasket 103 of the positioning assembly to fix the position of the gasket 103. The positioning jig 4013 is used to clamp the valve stem 102 of the assembly to fix the position of the valve stem 102. The positioning jig driving means is for driving the positioning jig 4013 to clamp the valve stem 102. The elastic reset member is used for driving the positioning jig 4013 to reset after the driving force of the positioning jig driving device is removed. Of course, the positioning jig 4013 may be driven to be reset by the positioning jig driving device without providing the elastic resetting member.

Referring to fig. 3, a turning and milling assembly 402 includes a cutter 4021, a cutter driving motor 4022, and a feed motor (not shown), wherein the cutter 4021 may be a milling cutter or a turning tool. An output shaft of the tool driving motor 4022 is connected with the tool 4021, and is used for driving the tool 4021 to move in a direction parallel to a surface to be processed, wherein the movement mode can be movement or rotation, and the movement track can be a straight line or a curve. Specifically, the output shaft of the cutter driving motor 4022 may be connected to the cutter 4021 through a connecting sleeve 4023, so as to facilitate replacement of different types of cutters 4021. An output shaft of the feed motor is connected with a body of the cutter driving motor 4022 through a transmission part, and is used for driving the cutter 4021 and the cutter driving motor 4022 to feed along the axial direction of the valve rod 102. The transmission member may be any member capable of converting a rotational motion of an output shaft of the feed motor into a linear motion, such as a rack-and-pinion member or a screw nut member.

As shown in fig. 4, the positioning seat 4011 is provided with a through hole a and a positioning surface B. As shown in fig. 5, the positioning fixture 4013 has a plurality of clamping portions 4013a, each clamping portion 4013a is sequentially arranged in the circumferential direction of the valve rod 102, in the embodiment shown in fig. 5, four clamping portions 4013a are provided, and in actual implementation, the number of clamping portions 4013a can be flexibly adjusted as required, so long as not less than two clamping portions are provided. As shown in fig. 6, one end of each clamping portion 4013a is provided with a clamping surface H which is designed to be tightly fitted with the outer peripheral surface of the valve stem 102, and when the outer peripheral surface of the valve stem 102 is a cylindrical surface, the clamping surface H is designed to be an arc surface. As shown in fig. 6, one end of the positioning ram 4012 is provided with a pressing surface K.

As shown in fig. 8, the assembly is inserted into the through hole a of the positioning seat 4011 before the processing. Then, the positioning ram driving device is started, and the positioning ram driving device drives the positioning ram 4012 to move along the axial direction of the valve rod 102 until the pressing surface K of the positioning ram 4012 presses the gasket 103 on the positioning surface B of the positioning seat 4011, so that the positioning of the gasket 103 is realized. Then, the positioning jig driving device is restarted, and the positioning jig driving device drives each clamping portion 4013a of the positioning jig 4013 to move in the axial direction perpendicular to the valve stem 102 until the clamping surface H of each clamping portion 4013a clamps the outer circumferential surface of the valve stem 102, thereby achieving positioning of the valve stem 102. After the positioning of the gasket 103 and the valve rod 102 is completed, a feeding motor and a cutter driving motor 4022 are started, the end face of one end, far away from the gasket 103, of the valve rod 102 is subjected to milling, and the feeding amount of the feeding motor is preset.

Specifically, as shown in fig. 4, the positioning seat 4011 may be provided with a plurality of clamping portion mounting holes C, one end of each clamping portion mounting hole C is communicated with the through hole a, and the other end of each clamping portion mounting hole C forms an orifice on the surface of the positioning seat 4011. As shown in fig. 5, the clamping portions 4013a of the positioning jig 4013 are mounted in the clamping portion mounting holes C in a one-to-one correspondence and are in guiding engagement with the clamping portion mounting holes C so as to move perpendicularly to the axial direction of the valve stem 102 under the guiding action of the clamping portion mounting holes C. By this arrangement, each clamping portion 4013a of the positioning jig 4013 can be supported and guided by the positioning seat 4011 without additionally providing a member for supporting and guiding the clamping portion 4013a, which is advantageous in simplifying the structure of the processing apparatus 400.

Specifically, as shown in fig. 4, the positioning seat 4011 may include a top seat 4011a and a bottom seat 4011b. Both the top seat 4011a and the base 4011b are provided with attachment holes (attachment holes G on the base 4011b are shown in fig. 5) through which fasteners pass to attach the two together. In the connected state, the bottom surface of the top base 4011a and the top surface of the base 4011b are bonded to each other. The bottom surface of footstock 4011a is equipped with a plurality of top recesses C1, and the top surface of base 4011b is equipped with a plurality of bottom recesses C2, and under the condition that the bottom surface of footstock 4011a and the top surface of base 4011b laminating each other, each top recess C1 is in one-to-one correspondence and each bottom recess C2 involutes and forms a plurality of clamping part mounting holes C. In this way, the assembly of the clamping portion 4013a and the positioning seat 4011 is facilitated, specifically, during the assembly, the top seat 4011a and the base 4011b can be separated, then the clamping portion 4013a is placed in the top groove C1 or the bottom groove C2, and then the top seat 4011a and the base 4011b are connected together in a butt joint manner.

As shown in fig. 4, in the case where the positioning seat 4011 includes the top seat 4011a and the base 4011b, one section of the through hole a is formed in the top seat 4011a, and the other section is formed in the base 4011b. In the embodiment shown in fig. 4, a portion of the through hole a formed in the top seat 4011a is provided with a first hole section A1, a second hole section A2 and a third hole section A3 in order from top to bottom. The first hole section A1 is a gradually expanding hole section gradually expanding from bottom to top, so that the hole wall of the first hole section A1 can be used for guiding the assembly body to be installed into the through hole a. The diameter of the second hole section A2 is larger than that of the third hole section A3, the body portion 101a of the bellows 101 is located in the second hole section A2, and the swaged portion 101c of the bellows 101 extends into the third hole section A3.

As shown in fig. 4, the top seat 4011a may be provided with a pit portion E and a sleeve portion F, the pit portion E forms an opening on the top surface of the top seat 4011a, the top end of the sleeve portion F protrudes from the bottom wall of the pit portion E to extend into the enclosing space of the side wall of the pit portion E, the top end surface of the sleeve portion F forms the positioning surface B, and the inner wall of the sleeve portion F participates in enclosing to form the through hole a. As shown in fig. 8, when the positioning ram 4012 presses the gasket 103, the positioning ram 4012 is at least partially located within the dimple E. The top seat 4011a in the form has high structural strength and small volume, and can avoid the positioning pressure head 4012, thereby avoiding influencing the movement of the positioning pressure head 4012.

In this embodiment, as shown in fig. 4, the top seat 4011a is provided with a plurality of elastic restoring member mounting holes D, one end of the elastic restoring member is mounted in the elastic restoring member mounting holes D, and the other end is connected to the clamping portion 4013a, specifically, as shown in fig. 7, a protrusion J is provided at an end of the clamping portion 4013a away from the clamping surface H, and the elastic restoring member abuts against the protrusion J (as understood with reference to fig. 7). When the driving force of the positioning jig driving device is removed, the clamping portion 4013a moves away from the valve rod 102 under the elastic force of the elastic restoring member, thereby restoring the clamping portion 4013a.

As shown in fig. 6, the positioning ram 4012 has a concave formation of an escape hole 4012b at one end of a pressing surface K, so that the escape hole 4012b is used to escape the flange portion 101b of the bellows 101, the pressing surface K is disposed around the escape hole 4012b, and the pressing surface K presses the outer ring region of the gasket 103. One end of the positioning ram 4012, which is far away from the pressing surface K, is provided with a connecting hole 4012a for connecting with a positioning ram driving device. Specifically, the positioning ram driving device can be an electric device, a pneumatic device, a hydraulic device or the like.

As shown in fig. 7, the clamping portion 4013a is provided with a concave top side at one end of the clamping surface H, so as to form an avoidance notch portion I, so that the avoidance notch portion I is used to avoid the riveting portion 101c of the corrugated tube 101, and the riveting portion 101c of the corrugated tube 101 is prevented from abutting against the clamping portion 4013a. The clamping portion 4013a is provided with a protrusion J at an end thereof away from the clamping surface H, and the protrusion J may be used to abut against the elastic restoring member, and a hole may be provided in the protrusion J to connect with the positioning jig driving device. Specifically, the positioning jig driving device may be an electric device, a pneumatic device, a hydraulic device, or the like.

The foregoing has outlined the principles and embodiments of the present application with the understanding that the present application is directed to a method and core idea of the present application. It should be noted that it would be obvious to those skilled in the art that various improvements and modifications can be made to the present application without departing from the principles of the present application, and such improvements and modifications fall within the scope of the claims of the present application.

Claims

1. The valve needle assembly is characterized by comprising a corrugated pipe, a valve rod, a gasket and a valve needle, wherein the corrugated pipe is sleeved on the periphery of the valve rod, one end of the corrugated pipe is connected with the gasket in a soldering manner, the other end of the corrugated pipe is connected with the valve rod in a soldering manner, one end of the valve rod, which is far away from the gasket, extends out of the corrugated pipe, the valve needle is in interference press fit with the periphery of one end of the valve rod, which is far away from the gasket, and the end face of the valve rod, which is far away from the gasket, is in collision with one end face of the gasket, and the end face of the valve rod, which is far away from the gasket, is a turning and milling surface.

2. The valve needle assembly of claim 1, wherein the bellows, stem and gasket are copper or copper alloy, and the valve needle is stainless steel.

3. Valve device, including needle subassembly, actuating assembly and valve body, its characterized in that, the needle subassembly is claim 1 or 2 the needle subassembly, the valve body is equipped with the installation cavity, the one end of installation cavity is equipped with the valve mouth, the installation cavity is kept away from the one end of valve mouth is equipped with spacing face, the needle subassembly install in the installation cavity, the gasket of needle subassembly be close to the one end terminal surface of needle with spacing face is contradicted, the actuating assembly supports and pushes away the valve rod, makes the valve rod drive the needle is to closing the direction of valve mouth removes.

4. A method for machining a valve needle assembly according to claim 1 or 2, characterized in that the machining method comprises the steps of:

the assembly is positioned, the assembly comprises a corrugated pipe, a valve rod and a gasket which are assembled together, one end face, close to the valve needle, of the gasket is used as a positioning reference surface, after the positioning is finished, the valve rod is far away from one end face of the gasket, milling is carried out until the distance between the one end face, far away from the gasket, of the valve rod and the one end face, close to the valve needle, of the gasket is equal to a preset value.

5. A machining device for a valve pin assembly for implementing the machining method of claim 4, the machining device comprising: a positioning component for positioning the assembly and a turning and milling component for turning and milling an end face of the valve rod, which is far away from the gasket.

6. The processing apparatus of claim 5, wherein the positioning assembly comprises:

the positioning seat is provided with a through hole and a positioning surface, and the assembly body is inserted into the through hole;

the positioning press head driving device drives the positioning press head to move along the axial direction of the valve rod so as to enable the pressing surface to press the gasket to the positioning surface of the positioning seat, thereby fixing the position of the gasket;

the positioning clamp comprises a plurality of clamping portions, each clamping portion is sequentially arranged in the circumferential direction of the valve rod, a clamping surface is arranged at one end of each clamping portion, and the positioning clamp driving device is used for driving the clamping portions to move along the axial direction perpendicular to the valve rod so that the clamping surfaces clamp the outer circumferential surface of the valve rod, and therefore the position of the valve rod is fixed.

7. The machining device according to claim 6, wherein the positioning seat is provided with a plurality of clamping portion mounting holes, one ends of the clamping portion mounting holes are communicated with the through holes, the other ends of the clamping portion mounting holes form holes in the surface of the positioning seat, and the clamping portions of the positioning clamp are mounted in the clamping portion mounting holes in one-to-one correspondence and are in guide fit with the clamping portion mounting holes so as to move in the axial direction perpendicular to the valve rod under the guide action of the clamping portion mounting holes.

8. The processing device of claim 7, wherein the positioning seat comprises a top seat and a base, the top seat and the base are fixedly connected through a fastener, the bottom surface of the top seat and the bottom surface of the base are mutually attached, a top groove is formed in the bottom surface of the top seat, a bottom groove is formed in the top surface of the base, and the top groove and the bottom groove are combined to form the clamping part mounting hole.

9. The processing device according to claim 8, wherein the top base is provided with a concave portion and a sleeve portion, the concave portion forms an opening on a top surface of the top base, a top end of the sleeve portion protrudes from a bottom wall of the concave portion to extend into a surrounding space of a side wall of the concave portion, a top end surface of the sleeve portion forms the positioning surface, and an inner wall of the sleeve portion participates in surrounding to form the through hole.

10. The processing device of claim 6, wherein the positioning press head is provided with a concave formation avoidance hole at one end of the pressing surface, the pressing surface is arranged around the avoidance hole, the avoidance hole is used for avoiding one end of the corrugated pipe connected with the gasket, and the pressing surface is used for pressing against an outer ring area of the gasket.

11. The processing device according to claim 6, wherein a notch portion is provided at an end of the holding portion near the valve stem, the notch portion being for avoiding an end of the bellows connected to the valve needle.

12. The machining device of claim 6, wherein the positioning assembly further comprises a resilient return member for driving the clamping portion to move in a direction perpendicular to the axial direction of the valve stem away from the valve stem to return the clamping portion.

13. A machining device according to any one of claims 5 to 12, wherein the turning and milling assembly comprises a cutter, a cutter drive motor, and a feed motor, an output shaft of the cutter drive motor being connected to the cutter for driving the cutter in a direction parallel to the surface to be machined, an output shaft of the feed motor being connected to the body of the cutter drive motor via a transmission member for driving the cutter and the cutter drive motor to feed in the axial direction of the valve stem.