CN115090976A

CN115090976A - Electrolytic machining clamp and electrolytic machining method for fuel nozzle spray hole

Info

Publication number: CN115090976A
Application number: CN202210771687.3A
Authority: CN
Inventors: 谷民凯; 岳磊; 丰莉; 初文潮; 廖鑫; 高军妮; 宋娜
Original assignee: AECC South Industry Co Ltd
Current assignee: AECC South Industry Co Ltd
Priority date: 2022-06-30
Filing date: 2022-06-30
Publication date: 2022-09-23

Abstract

The invention discloses an electrolytic machining fixture and an electrolytic machining method for spray holes of a fuel nozzle. And adopt the electrolyte circulation passageway of open flow field design for the structural design of electrolyte circulation passageway can be more nimble changeable. By adopting the electrolytic machining clamp, the electrolytic machining technology can be applied to the machining of the spray hole of the fuel nozzle, the electrolytic machining carries out material erosion based on the electrochemical anode dissolution principle, the electrolytic machining is not influenced by the cutting performance of the material, the cathode has no loss, the electrolytic machining clamp can be used for a long time, the machining efficiency is high, the surface quality of the machined spray hole is good, no recast layer exists, and the electrolytic machining clamp can be well suitable for mass production.

Description

Electrolytic machining clamp and electrolytic machining method for fuel nozzle spray hole

Technical Field

The invention relates to the technical field of fuel nozzle spray hole machining, in particular to an electrolytic machining fixture for a fuel nozzle spray hole, and in addition, particularly relates to an electrolytic machining method for the fuel nozzle spray hole.

Background

The fuel nozzle is used as a key component of an aircraft engine, and in order to further improve the flow coefficient and improve the atomization effect, a small tapered hole with taper is mostly adopted for a spray hole. Meanwhile, in order to meet the requirements of working conditions, the fuel nozzle is made of a material which is high in hardness and difficult to machine. At present, the drilling process commonly used for machining the spray hole of the fuel nozzle has the defects of small used cutter, poor rigidity, high price of a drill bit and short service life, a recast layer is inevitably generated in electric spark machining and laser machining, the surface quality of the machined hole is poor, and the process methods can not well meet the machining requirement of the spray hole of the fuel nozzle. The electrolytic machining is a technological method for machining and forming a workpiece according to a certain shape and size based on an electrochemical anode dissolution principle and by means of a formed cathode, and under the normal condition, a cathode cutter is lossless, can be used for a long time, has good surface quality, does not have recast layers and burrs, has high machining efficiency, and has good application prospect in the aspect of machining of fuel nozzle spray holes. Therefore, it is necessary to develop an electrolytic machining fixture for the spray hole of the fuel nozzle, apply an electrolytic machining process to the machining of the spray hole of the fuel nozzle, and overcome the defects of the traditional technology.

In addition, the design of the electrochemical machining fixture needs to consider factors such as the sealing performance, conductivity, insulation performance of the fixture, the design of the electrolyte flow channel structure, and the like in addition to the positioning and clamping of the general fixture design, so the design of the electrochemical machining fixture is much more complicated. Particularly, the influence of stray corrosion and sealing performance is caused, and a plurality of quick-change tools and alignment fixtures are difficult to be directly applied to the design of the electrolytic machining fixture. In the debugging of the actual electrolytic machining clamp, the verticality alignment of the cathode is mostly realized by lightly beating the outer circular surface of the clamp by using a rubber hammer, the method is complex in operation and large in workload, the requirement on high-efficiency production is hardly met, and the verticality of the machined hole is problematic if the cathode is not well aligned.

Disclosure of Invention

The invention provides an electrolytic machining clamp and an electrolytic machining method for a fuel nozzle spray hole, which aim to solve the defects of the existing machining process of the fuel nozzle spray hole and the technical problem that cathode verticality alignment is inconvenient to carry out.

According to an aspect of the present invention, there is provided an electrochemical machining jig for a nozzle hole of a fuel nozzle, including:

the main shaft connecting block is connected with a main shaft of the machine tool and is used for being connected with a power supply cathode;

the cathode positioning and aligning assembly is connected with the spindle connecting block and used for mounting a cathode and performing verticality alignment on the cathode, and the cathode is negatively charged after the spindle connecting block is connected to a power supply cathode;

the workpiece positioning assembly is arranged on a machine tool workbench and used for installing a fuel nozzle, the fuel nozzle is charged with positive electricity after being connected to a power supply anode, and an open electrolyte circulation channel is arranged in the workpiece positioning assembly;

when the electrolytic machining is ready, a machining gap is formed between the cathode and a pre-machining spray hole of the fuel nozzle through the movement of a main shaft of the machine tool, the inlet of the electrolyte circulation channel is connected with an electrolyte inlet pipe of the machine tool, and the cathode is fed along with the main shaft of the machine tool in the electrolytic machining process to machine the spray hole of the fuel nozzle.

Further, the cathode positioning and aligning assembly comprises an installation block, a cathode positioning block, a limiting block and a cathode clamping block, the installation block is arranged below the spindle connecting block and is in screw connection with the spindle connecting block, the cathode positioning block is arranged below the installation block and is in screw connection with the installation block, a first positioning hole which penetrates through the cathode positioning block is formed in the cathode positioning block up and down, the lower end of the cathode clamping block is arranged in the first positioning hole and is positioned between the cathode positioning block and the installation block, three aligning screws which are circumferentially and symmetrically distributed around the axis of the cathode clamping block are arranged on the installation block, the three aligning screws are abutted against the cathode clamping block, a second positioning hole which penetrates through the cathode clamping block up and down is formed in the cathode clamping block, the limiting block is arranged in the second positioning hole in an interference fit mode, and the upper surface of the limiting block is flush with the upper end surface of the second positioning hole, the cathode is fixedly installed in the second positioning hole, the upper end of the cathode is abutted against the limiting block, a machining gap is formed between the lower end of the cathode and a preprocessing jet hole of the fuel nozzle after the lower end of the cathode sequentially extends out of the second positioning hole and the first positioning hole, and the verticality of the cathode can be aligned and adjusted by adjusting the locking force of the alignment screws.

Furthermore, the cathode clamping block comprises a limiting section, an alignment adjusting section and a positioning section which are sequentially connected from top to bottom, the limiting section is located in a mounting hole in the mounting block, the number of the alignment screws is three, the alignment screws abut against the upper surface of the alignment adjusting section, the cross section of the positioning section is trapezoidal, the positioning section extends into the first positioning hole, the surface of the positioning section abuts against the upper end of the hole wall of the first positioning hole, and the positioning posture of the cathode clamping block in the first positioning hole can be adjusted by adjusting the locking force of the alignment screws, so that the cathode verticality alignment is realized.

Furthermore, a third positioning hole is formed in the side face of the cathode clamping block along the radial direction, and a fastening screw is arranged in the third positioning hole and used for locking the cathode in the second positioning hole.

Furthermore, the device also comprises an insulating block which is sleeved on the periphery of the cathode positioning block and is in screw connection with the mounting block, and the insulating block is used for preventing the cathode positioning block from being corroded in a stray mode.

Furthermore, the device also comprises an insulating sleeve which is sleeved at one end of the cathode extending out of the cathode positioning block and only exposes the processing blade, and the insulating sleeve is used for reducing stray corrosion of the non-processing blade part of the cathode on the fuel nozzle.

Further, the workpiece positioning assembly comprises a base, a workpiece positioning block, a workpiece clamping block and a plug, wherein a fourth positioning hole which penetrates through the base from top to bottom is formed in the base, the workpiece positioning block is installed in the fourth positioning hole and is in screw connection with the base, the plug is installed in the fourth positioning hole in an interference fit mode and is flush with the lower end face of the fourth positioning hole, a fifth positioning hole is formed in the workpiece positioning block, a fuel nozzle is installed in the fifth positioning hole, the workpiece clamping block is tightly pressed on the fuel nozzle and is in screw connection with the workpiece positioning block, the lower end of the cathode extends into the fifth positioning hole after penetrating through the workpiece positioning block and the workpiece clamping block and forms a machining gap with a pre-machining spray hole of the fuel nozzle, and a liquid inlet communicated with the fourth positioning hole is formed in the side face of the base, and the electrolyte flows in from the liquid inlet, sequentially enters the machining gap through the fourth positioning hole and the pre-machining spray hole on the fuel nozzle, and then flows out from the gap between the cathode and the fourth positioning hole.

Furthermore, two first pin holes which are circumferentially and symmetrically distributed are formed in the cathode positioning and aligning assembly, two second pin holes which are circumferentially and symmetrically distributed are formed in the workpiece positioning assembly, and the two first pin holes and the two second pin holes are arranged in a one-to-one correspondence mode and connected through bolts so as to achieve angular positioning between the cathode positioning and aligning assembly and the workpiece positioning assembly.

In addition, the invention also provides an electrolytic machining method of the spray hole of the fuel nozzle, which adopts the electrolytic machining clamp and comprises the following contents:

installing a fuel nozzle on the workpiece positioning assembly, placing the workpiece positioning assembly on a machine tool workbench, installing a cathode on the cathode positioning and aligning assembly, performing verticality alignment on the cathode, and connecting the spindle connecting block to a spindle of the machine tool;

connecting the main shaft connecting block to a power supply cathode, connecting the workpiece positioning assembly to a power supply anode, and connecting an inlet of an electrolyte circulation channel with an electrolyte inlet pipe of the machine tool;

and setting processing parameters, introducing electrolyte, and starting electrolytic machining, wherein the cathode feeds along with the main shaft of the machine tool to machine a spray hole of the fuel nozzle.

Further, the process of perpendicularity alignment of the cathode specifically comprises the following steps:

and (4) performing meter reading and alignment on the cathode, and in the alignment process, increasing the locking force of one alignment screw and simultaneously reducing the locking force of the other two alignment screws until the verticality of the cathode meets the requirement.

The invention has the following effects:

according to the electrolytic machining clamp for the spray hole of the fuel nozzle, the cathode is arranged on the cathode positioning and aligning assembly and is arranged on the machine tool spindle through the spindle connecting block, so that the up-and-down movement and adjustment of the cathode can be realized, the cathode is very convenient to mount and dismount, the alignment and adjustment of the perpendicularity of the cathode are facilitated, and the perpendicularity of the spray hole machining on the fuel nozzle is ensured. In addition, the electrolyte flow rate required by the processing of the spray hole of the fuel nozzle is small, so that the electrolyte circulation channel designed by an open flow field is adopted, and the structural design of the electrolyte circulation channel can be more flexible and changeable. When preparing to carry out electrolytic machining, an electrolytic machining gap is formed between a cathode and a preprocessing spray hole of a fuel nozzle by controlling the movement of a main shaft of a machine tool, an inlet of an electrolyte circulation channel is connected with an electrolyte inlet pipe of the machine tool, after machining parameters are set and electrolyte is introduced to start electrolytic machining, the cathode feeds along with the main shaft of the machine tool, and therefore the spray hole of the fuel nozzle is machined in an electrolytic mode. By adopting the electrolytic machining clamp, the electrolytic machining technology can be applied to the machining of the spray hole of the fuel nozzle, the electrolytic machining carries out material erosion based on the electrochemical anode dissolution principle, the electrolytic machining is not influenced by the cutting performance of the material, the cathode has no loss, the electrolytic machining clamp can be used for a long time, the machining efficiency is high, the surface quality of the machined spray hole is good, no recast layer exists, and the electrolytic machining clamp can be well suitable for mass production.

In addition, the electrolytic machining method of the fuel nozzle spray hole has the advantages.

In addition to the objects, features and advantages described above, other objects, features and advantages of the present invention are also provided. The present invention will be described in further detail below with reference to the drawings.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

fig. 1 is a schematic structural view of an electrochemical machining jig for a nozzle hole of a fuel nozzle according to a preferred embodiment of the present invention.

Fig. 2 is an enlarged schematic view at a in fig. 1.

Fig. 3 is a schematic structural view of the alignment screw locked on the cathode clamping block according to the preferred embodiment of the invention.

Fig. 4 is a schematic structural diagram of a cathode positioning block according to a preferred embodiment of the present invention.

Fig. 5 is a schematic structural view of a base in accordance with a preferred embodiment of the present invention.

Description of the reference numerals

1. A main shaft connecting block; 2. a cathode positioning and alignment assembly; 3. a workpiece positioning assembly; 4. an insulating block; 5. an insulating sleeve; 10. a cathode; 101. processing a blade; 20. a fuel nozzle; 21. mounting blocks; 22. a cathode positioning block; 23. a limiting block; 24. a cathode clamping block; 25. a first pin hole; 211. aligning the screw; 221. a first positioning hole; 241. a second positioning hole; 242. a third positioning hole; 243. a limiting section; 244. aligning the adjusting section; 245. a positioning section; 31. a base; 32. a workpiece positioning block; 33. a workpiece clamping block; 34. a plug; 35. a second pin hole; 311. a fourth positioning hole; 312. a liquid inlet; 321. and a fifth positioning hole.

Detailed Description

The embodiments of the invention will be described in detail below with reference to the accompanying drawings, but the invention can be embodied in many different forms, which are defined and covered by the following description.

As shown in fig. 1 to 5, a preferred embodiment of the present invention provides an electrochemical machining jig for a nozzle hole of a fuel nozzle, including:

the main shaft connecting block 1 is connected with a main shaft of the machine tool and is used for being connected with a power supply cathode;

the cathode positioning and aligning assembly 2 is connected with the spindle connecting block 1 and is used for installing a cathode 10 and performing perpendicularity alignment on the cathode 10, and after the spindle connecting block 1 is connected to a power supply cathode, the cathode 10 is negatively charged;

the workpiece positioning assembly 3 is arranged on a machine tool workbench and used for installing a fuel nozzle 20, the fuel nozzle 20 is positively charged after being connected to a power supply positive electrode, and an open electrolyte circulation channel is arranged in the workpiece positioning assembly 3;

when preparing to carry out electrolytic machining, a machining gap is formed between the cathode 10 and a pre-machining spray hole of the fuel nozzle 20 through the movement of a main shaft of a machine tool, the inlet of an electrolyte circulation channel is connected with an electrolyte inlet pipe of the machine tool, and the cathode 10 is fed along with the main shaft of the machine tool in the electrolytic machining process to machine the spray hole of the fuel nozzle 20.

It can be understood that the electrolytic machining fixture for the nozzle holes of the fuel nozzle of the embodiment can realize the up-and-down movement adjustment of the cathode 10 by installing the cathode 10 on the cathode positioning and aligning component 2 and installing the cathode 10 on the main shaft of the machine tool through the main shaft connecting block 1, the cathode 10 is very convenient to install and disassemble, the alignment adjustment of the perpendicularity of the cathode 10 is convenient, and the perpendicularity of the nozzle holes on the fuel nozzle 20 is ensured. In addition, considering that the flow rate of the electrolyte required for processing the spray holes of the fuel nozzle 20 is small, the electrolyte circulation channel designed by the open flow field is adopted, so that the structural design of the electrolyte circulation channel can be more flexible and changeable. When preparing to carry out electrolytic machining, an electrolytic machining gap is formed between the cathode 10 and a pre-machining spray hole of the fuel nozzle 20 by controlling the movement of a main shaft of a machine tool, an inlet of an electrolyte circulation channel is connected with an electrolyte inlet pipe of the machine tool, after machining parameters are set and electrolyte is introduced to start electrolytic machining, the cathode 10 is fed along with the main shaft of the machine tool, so that the spray hole of the fuel nozzle 20 is machined in an electrolytic mode, and the whole clamp is simple in structure and very convenient to assemble and disassemble. By adopting the electrolytic machining clamp, the electrolytic machining technology can be applied to the machining of the spray hole of the fuel nozzle 20, the electrolytic machining carries out material erosion based on the electrochemical anode dissolution principle, the material erosion is not influenced by the cutting performance of the material, the cathode 10 has no loss, the electrolytic machining clamp can be used for a long time, the machining efficiency is high, the surface quality of the machined spray hole is good, no recast layer exists, and the electrolytic machining clamp can be well suitable for mass production.

It will be appreciated that before the electrolytic machining, a straight circular hole is usually pre-machined in the fuel nozzle 20 by drilling, and then the shape and size of the nozzle hole is machined by the electrolytic machining. The main shaft connecting block 1 is specifically connected with a machine tool main shaft through a screw, and the cathode positioning and aligning assembly 2 is attached to the lower surface of the main shaft connecting block 1 and connected with the main shaft connecting block through a screw. In addition, in order to ensure the conductivity and the corrosion resistance, the spindle connecting block 1, the cathode positioning and aligning assembly 2 and the workpiece positioning assembly 3 are all made of stainless steel materials. When the spindle connecting block 1 is connected with a power supply cathode, the cathode 10 is charged with negative electricity, when the workpiece positioning assembly 3 is connected with a power supply anode, the fuel nozzle 20 is charged with positive electricity, and when electrolyte flows through a machining gap between the cathode 10 and the fuel nozzle 20, conduction current is formed between the cathode 10 and the fuel nozzle 20, so that electrolytic machining is realized.

It can be understood that the cathode positioning and aligning assembly 2 comprises a mounting block 21, a cathode positioning block 22, a limiting block 23 and a cathode clamping block 24, wherein the mounting block 21 is arranged below the spindle connecting block 1 and is in screw connection with the spindle connecting block 1, and the cathode positioning block 22 is arranged below the mounting block 21 and is in screw connection with the mounting block 21. The cathode positioning block 22 is provided with a first positioning hole 221 which penetrates through the cathode positioning block 22 from top to bottom, the lower end of the cathode clamping block 24 is arranged in the first positioning hole 221 and is integrally located between the cathode positioning block 22 and the mounting block 21, the mounting block 21 is provided with three aligning screws 211 which are circumferentially and symmetrically distributed around the axis of the cathode clamping block 24, the three aligning screws 211 are abutted against the cathode clamping block 24, and the perpendicularity of the cathode 10 can be aligned and adjusted by adjusting the locking force of the three aligning screws 211. The cathode clamping block 24 is provided with a second positioning hole 241 penetrating vertically, the limiting block 23 is installed in the second positioning hole 241 in an interference fit manner, the upper surface of the limiting block is flush with the upper end surface of the second positioning hole 241, and the cathode 10 is fixedly installed in the second positioning hole 241, and the upper end of the cathode abuts against the limiting block 23. The lower end of the cathode 10 sequentially extends out of the second positioning hole 241 and the first positioning hole 221 to form a machining gap with a pre-machining spray hole of the fuel nozzle 20.

It can be understood that, in the present invention, the first positioning hole 221 is formed in the cathode positioning block 22, after the cathode 10 is fixedly mounted on the cathode clamping block 24, the cathode clamping block 24 is mounted in the first positioning hole 221 and integrally located between the cathode positioning block 22 and the mounting block 21, the cathode clamping block 24 is locked in the first positioning hole 221 by the three alignment screws 211 on the mounting block 21, so as to realize the positioning of the cathode clamping block 24, and the cathode clamping block 24 is in line contact with the upper end circumference of the hole wall of the first positioning hole 221. When the perpendicularity of the cathode 10 needs to be adjusted, the positioning posture of the cathode clamping block 24 is adjusted by adjusting the locking force exerted on the cathode clamping block 24 by the three alignment screws 211, and the locking force of one alignment screw 211 is increased while the locking force of the other two alignment screws 211 is reduced, so that the perpendicularity alignment adjustment of the cathode 10 can be realized, the alignment structure is simple, the rapid alignment of the cathode 10 can be realized, and the alignment time is saved. In addition, in another embodiment of the present invention, the number of the first positioning holes 221 and the cathode clamping blocks 24 may be two, three or more, at least two first positioning holes 221 are circumferentially and symmetrically distributed around the axis of the cathode positioning block 22, one cathode clamping block 24 is positioned in each first positioning hole 221, and at least two fuel nozzles 20 are correspondingly mounted on the workpiece positioning assembly 3, so that the nozzle hole machining of at least two fuel nozzles 20 can be realized at one time, and the machining efficiency is greatly improved.

Specifically, the cathode clamping block 24 includes a limiting section 243, an alignment adjusting section 244 and a positioning section 245 which are sequentially connected from top to bottom, the limiting section 243 is located in the mounting hole of the mounting block 21, the limiting block 23 is hammered into the second positioning hole 241 in a manner of rubber hammer striking, and is correspondingly located in the limiting section 243, and the upper end face of the limiting block 23 is flush with the upper end face of the limiting section 243. The radial width of the alignment adjustment section 244 is greater than the radial width of the limiting section 243, and the three alignment screws 211 abut against the upper surface of the alignment adjustment section 244, so that a locking force can be applied to the cathode clamping block 24. The cross-sectional shape of the positioning section 245 is a trapezoid, for example, the positioning section 245 is a truncated cone, the lower end portion of the positioning section 245 extends into the first positioning hole 221, the outer surface of the positioning section abuts against the upper end of the hole wall of the first positioning hole 221, the positioning section 245 is in line contact with the upper end of the hole wall of the first positioning hole 221, so that the positioning posture of the cathode clamping block 24 in the first positioning hole 221 can be adjusted by adjusting the locking force of the three alignment screws 211, and the perpendicularity alignment of the cathode 10 is realized.

Optionally, a third positioning hole 242 is formed in a side surface of the cathode clamping block 24 along the radial direction, and a fastening screw is disposed in the third positioning hole 242 for locking the cathode 10 in the second positioning hole 241. The third positioning hole 242 is specifically disposed on a side surface of the alignment adjusting section 244.

It can be understood that, according to the invention, the second positioning hole 241 is formed in the cathode clamping block 24, the cathode 10 is installed in the second positioning hole 241, the cathode 10 is axially limited by the limiting block 23, and the cathode 10 is radially limited and circumferentially limited by the fastening screw in the third positioning hole 242, so that the cathode 10 is locked in the second positioning hole 241, the cathode 10 and the cathode clamping block 24 are fixedly connected into a whole, and the perpendicularity alignment adjustment of the cathode 10 is facilitated by adjusting the positioning posture of the cathode clamping block 24.

Optionally, the electrochemical machining fixture further comprises an insulating block 4 sleeved on the periphery of the cathode positioning block 22 and connected with the mounting block 21 through screws, and the insulating block 4 is used for preventing the cathode positioning block 22 from being corroded by stray electricity. It can be understood that, because the electrolyte flow channel of the present invention adopts an open flow field design, the electrolyte can flow to the gap between the cathode positioning and alignment assembly 2 and the workpiece positioning assembly 3, and the stray corrosion of the cathode positioning block 22 can be prevented by sleeving the insulating block 4 on the periphery of the cathode positioning block 22.

Optionally, the electrochemical machining fixture further includes an insulating sleeve 5 sleeved on one end of the cathode 10 extending out of the cathode positioning block 22 and only exposing the machining edge 101, for reducing stray corrosion of the non-machining edge portion of the cathode 10 to the fuel nozzle 20. It can be understood that, in the present invention, the insulating sleeve 5 is sleeved on the end of the cathode 10 extending out of the cathode positioning block 22, and only the processing edge 101 is exposed, so that the conduction current can be prevented from being formed between the non-processing edge part of the cathode 10 and the fuel nozzle 20, and the conduction current can be formed only between the processing edge 101 and the fuel nozzle 20, which is beneficial to reducing the stray corrosion to the fuel nozzle 20 and improving the processing quality of the spray hole.

It can be understood that the workpiece positioning assembly 3 includes a base 31, a workpiece positioning block 32, a workpiece clamping block 33 and a plug 34, the base 31 is provided with a fourth positioning hole 311 penetrating vertically, the workpiece positioning block 32 is installed in the fourth positioning hole 311 and is in screw connection with the base 31, and the plug 34 is installed in the fourth positioning hole 311 in an interference fit manner and is flush with the lower end surface of the fourth positioning hole 311, so as to prevent liquid leakage. When mounting, the stopper 34 is hammered into the bottom of the fourth positioning hole 311 by a rubber hammer, and the bottom surface of the stopper 34 is flush with the lower end surface of the fourth positioning hole 311, preventing the electrolyte from leaking out of the fourth positioning hole 311. A fifth positioning hole 321 is formed in the workpiece positioning block 32, the fuel nozzle 20 is installed in the fifth positioning hole 321, and the workpiece clamping block 33 is tightly pressed on the fuel nozzle 20 and is in screw connection with the workpiece positioning block 32. The fifth positioning hole 321 is preferably a stepped hole, the fuel nozzle 20 is overlapped on the stepped surface, and the workpiece holding block 33 is pressed on the upper end surface of the fuel nozzle 20. The lower end of the cathode 10 extends into the fifth positioning hole 321 after penetrating through the workpiece positioning block 32 and the workpiece clamping block 33, and forms a machining gap with the pre-machining nozzle hole of the fuel nozzle 20, the side surface of the base 31 is provided with a liquid inlet 312 communicated with the fourth positioning hole 311, and the electrolyte flows in from the liquid inlet 312, sequentially enters the machining gap through the fourth positioning hole 311 and the pre-machining nozzle hole on the fuel nozzle 20, and then flows out from the gap between the cathode 10 and the fourth positioning hole 311. Optionally, in order to ensure conductivity and corrosion resistance, the base 31, the workpiece positioning block 32, and the workpiece clamping block 33 are all made of stainless steel materials. The plug 34 is made of an insulating material.

It can be understood that the fourth positioning hole 311 penetrating vertically is opened in the base 31 to serve as a mounting hole for the workpiece positioning block 32 and a flow hole for the electrolyte. In addition, the fuel nozzle 20 is pressed in the fifth positioning hole 321 through the workpiece clamping block 33, and the workpiece positioning block 32 is in screw connection with the base 31, so that the fuel nozzle 20 is convenient to assemble and disassemble, and the mounting verticality of the fuel nozzle 20 is ensured. In addition, the number of the fourth positioning holes 311, the number of the workpiece positioning blocks 32, the number of the workpiece clamping blocks 33 and the number of the plugs 34 are at least two, and the number and the positions of the fourth positioning holes 221 and the number and the positions of the cathode clamping blocks 24 correspond to one another, so that the nozzle hole machining of at least two fuel nozzles 20 can be realized at one time, and the machining efficiency is greatly improved.

Optionally, two first pin holes 25 which are circumferentially and symmetrically distributed are formed in the cathode positioning and aligning assembly 2, two second pin holes 35 which are circumferentially and symmetrically distributed are formed in the workpiece positioning assembly 3, and the two first pin holes 25 and the two second pin holes 35 are arranged in a one-to-one correspondence manner and connected through bolts, so that angular positioning between the cathode positioning and aligning assembly 2 and the workpiece positioning assembly 3 is realized. Specifically, two first pin holes 25 which are circumferentially and symmetrically distributed are formed in the cathode positioning block 22, two second pin holes 35 which are circumferentially and symmetrically distributed are formed in the base 31, and the two first pin holes 25 and the two second pin holes 35 are arranged in a one-to-one correspondence and connected through a pin, so that angular positioning between the cathode positioning block 22 and the base 31 is realized.

In addition, another embodiment of the present invention further provides an electrochemical machining method for a nozzle hole of a fuel nozzle, preferably using the above electrochemical machining fixture, including the following steps:

installing the fuel nozzle 20 on the workpiece positioning component 3, placing the workpiece positioning component 3 on a machine tool workbench, installing the cathode 10 on the cathode positioning and aligning component 2, performing verticality alignment on the cathode 10, and connecting the spindle connecting block 1 to a spindle of a machine tool;

connecting the main shaft connecting block 1 to a power supply cathode, connecting the workpiece positioning component 3 to a power supply anode, and connecting an inlet of an electrolyte circulation channel with an electrolyte inlet pipe of a machine tool;

machining parameters are set, electrolyte is introduced to start electrolytic machining, and the cathode 10 is fed along with a main shaft of the machine tool to machine a spray hole of the fuel nozzle 20.

It can be understood that, in the electrochemical machining method for the nozzle hole of the fuel nozzle in the embodiment, the cathode 10 is mounted on the cathode positioning and aligning assembly 2 and is mounted on the spindle of the machine tool through the spindle connecting block 1, so that the up-and-down movement adjustment of the cathode 10 can be realized, the cathode 10 is very convenient to mount and dismount, the alignment adjustment of the perpendicularity of the cathode 10 is facilitated, and the perpendicularity of the nozzle hole machining on the fuel nozzle 20 is ensured. In addition, considering that the flow rate of the electrolyte required by the processing of the spray holes of the fuel nozzle 20 is small, the electrolyte circulation channel designed by the open flow field is adopted, so that the structural design of the electrolyte circulation channel can be more flexible and changeable. When preparing to carry out electrolytic machining, an electrolytic machining gap is formed between the cathode 10 and a pre-machining spray hole of the fuel nozzle 20 by controlling the movement of a main shaft of a machine tool, an inlet of an electrolyte circulation channel is connected with an electrolyte inlet pipe of the machine tool, after machining parameters are set and electrolyte is introduced to start electrolytic machining, the cathode 10 is fed along with the main shaft of the machine tool, so that the spray hole of the fuel nozzle 20 is machined in an electrolytic mode, and the whole clamp is simple in structure and very convenient to assemble and disassemble. The invention applies the electrochemical machining technology to the processing of the spray hole of the fuel nozzle 20, the electrochemical machining carries out material erosion based on the electrochemical anode dissolution principle, the electrochemical machining is not influenced by the cutting performance of the material, the cathode 10 has no loss, the electrochemical machining can be used for a long time, the processing efficiency is high, the surface quality of the processed spray hole is good, no recast layer exists, and the electrochemical machining technology is well suitable for mass production.

The process of perpendicularity alignment of the cathode 10 specifically includes:

the cathode 10 is subjected to meter reading and alignment, and in the alignment process, the locking force of one alignment screw 211 is increased while the locking force of the other two alignment screws 211 is reduced until the verticality of the cathode 10 meets the requirement.

Specifically, the electrolytic machining process of the invention specifically comprises the following steps:

the limiting block 23 is hammered into the second positioning hole 241 of the cathode clamping block 24 by a rubber hammer to ensure that the end faces are flush, the cathode 10 is placed into the second positioning hole 241 of the cathode clamping block 24 and is tightly pressed by a fastening screw on the side face, and then the cathode clamping block 24 is placed into the first positioning hole 221 of the cathode positioning block 22. And then the mounting block 21 is connected with the cathode positioning block 22 by screws, so that the cathode clamping block 24 is arranged between the mounting block 21 and the cathode positioning block 22. Then, the spindle connection block 1 is screwed to the mounting block 21, and the spindle connection block 1 is connected to the machine tool spindle.

Then, the cathode 10 is subjected to meter making and alignment, when one alignment screw 211 is tightened and applied with force, the other two alignment screws 211 are properly loosened and released with force, so that the positioning posture of the cathode clamping block 24 is adjusted, and the perpendicularity alignment adjustment of the cathode 10 is performed. After the alignment is completed, the insulating sleeve 5 is sleeved on the cathode 10, and only the processing blade 101 is left.

Placing the fuel nozzle 20 into the fifth positioning hole 321 of the workpiece positioning block 32, and screwing the workpiece clamping block 33 and the workpiece positioning block 32 to clamp the fuel nozzle 20; then, the plug 34 is hammered into the fourth positioning hole 311 of the base 31 from the bottom by using a rubber hammer, so as to ensure that the end faces are flush; then, the workpiece positioning block 32 is placed into the fourth positioning hole 311 of the base 31 from top to bottom, and the workpiece positioning block 32 is screwed to the base 31.

And then the first pin hole 25 on the cathode positioning block 22 is connected with the second pin hole 35 on the base 31 in a plug-in manner, so that the angular positioning is completed, and the base 31 is pressed on the machine tool workbench by a pressing plate. Then, the plug pin is pulled out, and the insulating block 4 is sleeved on the periphery of the cathode positioning block 22 and is in screw connection with the mounting block 21.

The liquid inlet 312 of the base 31 is connected with a liquid inlet pipe of the machine tool, the electrolyte enters from the liquid inlet 312 and flows out after flowing through the processing area, and an open flow field is adopted because the flow rate of the electrolyte is small. The spindle connecting block 1 is connected to the negative electrode of the machining power supply to charge the cathode 10 negatively, and the table is connected to the positive electrode of the machining power supply to charge the fuel nozzle 20 positively.

And setting processing parameters, introducing electrolyte, starting processing, feeding the cathode 10 by a main shaft of a random machine tool, and processing a required spray hole shape on the fuel nozzle 20 through electrochemical corrosion.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The utility model provides an electrolytic machining anchor clamps of fuel nozzle orifice which characterized in that includes:

the main shaft connecting block (1) is connected with a main shaft of the machine tool and is used for being connected with a negative electrode of a power supply;

the cathode positioning and aligning assembly (2) is connected with the spindle connecting block (1) and used for installing a cathode (10) and performing verticality alignment on the cathode (10), and after the spindle connecting block (1) is connected to a power supply cathode, the cathode (10) is charged with negative electricity;

the workpiece positioning assembly (3) is arranged on a machine tool workbench and used for installing a fuel nozzle (20), the fuel nozzle (20) is positively charged after a power supply positive electrode is connected, and an open electrolyte circulation channel is arranged in the workpiece positioning assembly (3);

when the electrolytic machining is ready, a machining gap is formed between the cathode (10) and a pre-machining spray hole of the fuel nozzle (20) through the movement of a main shaft of the machine tool, the inlet of the electrolyte circulation channel is connected with an electrolyte inlet pipe of the machine tool, and the cathode (10) is fed along with the main shaft of the machine tool during the electrolytic machining process to machine the spray hole of the fuel nozzle (20).

2. The electrolytic machining clamp for the spray hole of the fuel nozzle of claim 1, characterized in that the cathode positioning and aligning assembly (2) comprises an installation block (21), a cathode positioning block (22), a limiting block (23) and a cathode clamping block (24), the installation block (21) is arranged below the spindle connecting block (1) and is in screw connection with the spindle connecting block (1), the cathode positioning block (22) is arranged below the installation block (21) and is in screw connection with the installation block (21), a first positioning hole (221) penetrating up and down is formed in the cathode positioning block (22), the lower end of the cathode clamping block (24) is installed in the first positioning hole (221) and is located between the cathode positioning block (22) and the installation block (21), three aligning screws (211) are arranged on the installation block (21) and are circumferentially and symmetrically distributed around the axis of the cathode clamping block (24), the three aligning screws (211) are abutted against the cathode clamping block (24), a second positioning hole (241) which penetrates through the cathode clamping block (24) from top to bottom is formed in the cathode clamping block (24), the limiting block (23) is installed in the second positioning hole (241) in an interference fit mode, the upper surface of the limiting block is flush with the upper end face of the second positioning hole (241), the cathode (10) is fixedly installed in the second positioning hole (241), the upper end of the cathode (10) is abutted against the limiting block (23), the lower end of the cathode (10) sequentially extends out of the second positioning hole (241), the first positioning hole (221) and a preprocessing jet hole of the fuel nozzle (20) to form a processing gap, and the verticality of the cathode (10) can be aligned and adjusted by adjusting the locking force of the three aligning screws (211).

3. The electrolytic machining clamp for the spray hole of the fuel nozzle as recited in claim 2, wherein the cathode clamping block (24) comprises a limiting section (243), an alignment adjusting section (244) and a positioning section (245) which are sequentially connected from top to bottom, the limiting section (243) is located in a mounting hole in the mounting block (21), three alignment screws (211) abut against the upper surface of the alignment adjusting section (244), the cross section of the positioning section (245) is trapezoidal, the positioning section (245) partially extends into the first positioning hole (221) and abuts against the upper end of the hole wall of the first positioning hole (221), and the positioning posture of the cathode clamping block (24) in the first positioning hole (221) can be adjusted by adjusting the locking force of the three alignment screws (211), so that the verticality alignment of the cathode (10) is realized.

4. The fuel nozzle orifice electrochemical machining fixture of claim 2, characterized in that the side surface of the cathode clamping block (24) is provided with a third positioning hole (242) along the radial direction, and a fastening screw is arranged in the third positioning hole (242) and used for locking the cathode (10) in the second positioning hole (241).

5. The electrolytic machining fixture for the spray hole of the fuel nozzle as claimed in claim 2, further comprising an insulating block (4) sleeved on the periphery of the cathode positioning block (22) and in screw connection with the mounting block (21) for preventing the cathode positioning block (22) from generating stray corrosion.

6. The electrolytic machining fixture for the spray hole of the fuel nozzle as recited in claim 2, further comprising an insulating sleeve (5) sleeved on one end of the cathode (10) extending out of the cathode positioning block (22) and only exposing the machining edge (101), for reducing stray corrosion of the non-machining edge part of the cathode (10) to the fuel nozzle (20).

7. The electrochemical machining fixture for the spray hole of the fuel nozzle according to claim 1, characterized in that the workpiece positioning assembly (3) comprises a base (31), a workpiece positioning block (32), a workpiece clamping block (33) and a plug (34), wherein a fourth positioning hole (311) penetrating from top to bottom is formed in the base (31), the workpiece positioning block (32) is installed in the fourth positioning hole (311) and is in screw connection with the base (31), the plug (34) is installed in the fourth positioning hole (311) in an interference fit manner and is flush with the lower end face of the fourth positioning hole (311), a fifth positioning hole (321) is formed in the workpiece positioning block (32), the fuel nozzle (20) is installed in the fifth positioning hole (321), and the workpiece clamping block (33) is pressed on the fuel nozzle (20) and is in screw connection with the workpiece positioning block (32), the lower end of the cathode (10) extends into the fifth positioning hole (321) after penetrating through the workpiece positioning block (32) and the workpiece clamping block (33) and then extends into the fifth positioning hole and forms a machining gap with a pre-machining spray hole of the fuel nozzle (20), a liquid inlet (312) communicated with the fourth positioning hole (311) is formed in the side face of the base (31), electrolyte flows in from the liquid inlet (312), enters the machining gap through the fourth positioning hole (311) and the pre-machining spray hole in the fuel nozzle (20) in sequence and then flows out from the gap between the cathode (10) and the fourth positioning hole (311).

8. The electrolytic machining clamp for the spray hole of the fuel nozzle as set forth in claim 1, characterized in that two first pin holes (25) are formed in the cathode positioning and aligning assembly (2) and are circumferentially symmetrically distributed, two second pin holes (35) are formed in the workpiece positioning assembly (3) and are circumferentially symmetrically distributed, and the two first pin holes (25) and the two second pin holes (35) are correspondingly arranged one by one and are connected through a pin, so as to realize angular positioning between the cathode positioning and aligning assembly (2) and the workpiece positioning assembly (3).

9. An electrolytic machining method of a fuel nozzle spray hole adopts the electrolytic machining clamp as claimed in any one of claims 1 to 8, and is characterized by comprising the following steps:

installing a fuel nozzle (20) on a workpiece positioning component (3), placing the workpiece positioning component (3) on a machine tool workbench, installing a cathode (10) on a cathode positioning and aligning component (2), performing verticality alignment on the cathode (10), and connecting a main shaft connecting block (1) to a main shaft of a machine tool;

connecting the main shaft connecting block (1) to the negative electrode of a power supply, connecting the workpiece positioning component (3) to the positive electrode of the power supply, and connecting the inlet of an electrolyte circulation channel with an electrolyte inlet pipe of a machine tool;

and setting processing parameters, introducing electrolyte to start electrolytic processing, and feeding the cathode (10) along with a main shaft of the machine tool to process a spray hole of the fuel nozzle (20).

10. The electrolytic machining method for the nozzle hole of the fuel nozzle as set forth in claim 9, wherein the process of vertically aligning the cathode (10) is specifically as follows:

the cathode (10) is subjected to meter reading and alignment, and in the alignment process, the locking force of one alignment screw (211) is increased while the locking force of the other two alignment screws (211) is reduced until the verticality of the cathode (10) meets the requirement.