CN110640614B

CN110640614B - Negative pressure polishing device and method for polishing blind holes of conductive workpiece

Info

Publication number: CN110640614B
Application number: CN201910984170.0A
Authority: CN
Inventors: 单晓杭; 汪佳成; 张利; 李研彪; 叶必卿
Original assignee: Zhejiang University of Technology ZJUT
Current assignee: Zhejiang University of Technology ZJUT
Priority date: 2019-10-16
Filing date: 2019-10-16
Publication date: 2024-04-09
Anticipated expiration: 2039-10-16
Also published as: CN110640614A

Abstract

The invention discloses a negative pressure polishing device and a method for polishing a blind hole of a conductive workpiece, wherein the negative pressure polishing device comprises a workbench, a movable positioning device, a rotary runner device and a rotary magnetic field device, the movable positioning device is arranged on the workbench, the rotary runner device is arranged on the movable positioning device, and the rotary magnetic field device is fixed on the workbench obliquely below the rotary runner device; according to the invention, the blind holes of the blind hole type workpiece can be polished, and the blind holes of the workpiece to be polished are in a negative pressure state by pumping, so that abrasive particle flows can smoothly enter the blind holes; the abrasive particle flow used in the invention is liquid metal abrasive particle flow, metal particles in the liquid metal abrasive particle flow can form good contact with the surface of a workpiece to be processed under the action of a rotating magnetic field generated by the three-phase stator coil, and micro cutting is carried out, so that the surface of a blind hole of the workpiece to be processed can not generate mechanical deformation; so that the polishing efficiency is faster, the effect is better and the micro-cutting is performed.

Description

Negative pressure polishing device and method for polishing blind holes of conductive workpiece

Technical Field

The invention relates to the field of liquid metal, in particular to a negative pressure polishing device and method for polishing blind holes of a conductive workpiece.

Background

The 3D printing technology is also called additive manufacturing technology, namely an advanced manufacturing technology called rapid forming in China, and the essential principle is dispersion and accumulation, namely, the manufacturing of a three-dimensional entity is converted into accumulation of two-dimensional layers and continuous superposition along the forming direction by slicing a solid model with the aid of a computer, so that the manufacturing of the three-dimensional entity is finally realized. As 3D printing technology is used more and more widely, blind hole products generated by using the 3D printing technology are more and more generated. The blind holes refer to blind holes which are not communicated with the through holes, so that the blind holes are widely applied to life and industrial production, and meanwhile, the high-precision blind holes are increasingly widely used, such as blind holes of pressure sensor shells; key parts in the vehicle engine such as a plunger, an electromagnetic valve seat, an intermediate body of an oil sprayer, a blind hole of a pump body and the like are used for realizing the efficient operation of the engine; blind holes in prosthetic heart valve holders in medical applications.

Although 3D printing technology is better and better, the fineness is high, the surface of a model printed by 3D is rough. In order to solve the problem of surface roughness, the traditional post-treatment methods adopt mechanical polishing, surface sand blasting and the like, but the traditional methods are easy to destroy the shape required by the parts, dust generated in the polishing process affects the environment and processing workers, and the traditional polishing method cannot polish blind hole type workpieces with small apertures printed in 3D (three-dimensional) mode, in particular blind holes of the blind hole type workpieces.

Disclosure of Invention

The invention aims to solve the problem that the existing polishing method cannot polish blind holes of a conductive workpiece printed by a 3D printing technology, and provides a negative pressure polishing device and a method for polishing blind holes of a conductive workpiece.

The invention realizes the above purpose through the following technical scheme: the negative pressure polishing device for polishing the blind hole of the conductive workpiece comprises a workbench, a movable positioning device, a rotary runner device and a rotary magnetic field device, wherein the movable positioning device is arranged on the workbench;

The movable positioning device comprises a horizontal module mounting frame, a horizontal linear module, a horizontal module driving motor, a vertical linear module and a vertical module driving motor, wherein the horizontal module mounting frame is fixed on the workbench; the horizontal linear module is horizontally fixed on the horizontal module mounting frame, the horizontal module driving motor is fixed at one end of the horizontal linear module, and a driving shaft of the horizontal module driving motor is connected with the horizontal linear module and drives a horizontal sliding block on the horizontal linear module to do linear motion along the horizontal direction; the vertical linear module is vertically fixed on a horizontal sliding block of the horizontal linear module, the vertical module driving motor is fixed at the upper end of the vertical linear module, and a driving shaft of the vertical module driving motor is connected with the vertical linear module and drives the vertical sliding block on the vertical linear module to do linear motion along the vertical direction; the rotary runner device is arranged on a vertical sliding block of the vertical linear module, and the rotary magnetic field device is arranged on a workbench beside the horizontal module mounting frame; the rotating magnetic field device and the rotating runner device are arranged on the same side of the vertical sliding block;

the rotating magnetic field device comprises a supporting block, a rotating driven disc, a turntable base, a three-phase stator coil, a flange-type over-electricity slip ring, a conductive copper sheet and a stator coil fixing seat, wherein the supporting block is fixed on a workbench, and an inclined upward installation inclined plane is arranged on the supporting block; the mounting inclined plane is provided with a circular groove for mounting the stator coil fixing seat and an electric slip ring mounting groove for mounting the flange type electric slip ring; the stator coil fixing seat is embedded in the circular groove of the installation inclined plane, the flange type electric slip ring is embedded in the electric slip ring installation groove of the inclined plane, the stator end of the flange type electric slip ring is fixedly arranged in the electric slip ring installation groove, and the rotor end of the flange type electric slip ring is fixedly connected with the fixed end of the rotary driven disc; the rotary driven plate is provided with a workpiece mounting groove, the inner wall of the workpiece mounting groove of the rotary driven plate is provided with a conductive copper sheet, the conductive copper sheet is connected with a lead wire at the rotor end of the flange-type over-electric slip ring, and the lead wire at the stator end of the flange-type over-electric slip ring is connected with an input wire of an external square wave alternating current power supply; the three-phase stator coil is fixed on the stator coil fixing seat and is arranged around the whole rotary driven disc and the rotary disc base; the input end of the three-phase stator coil is connected with an external sine alternating current power supply;

The rotary runner device comprises a rotary clamping head, a rotary joint fixing seat, a runner fixing plate, a sliding rail connecting plate, an extraction opening one-way valve, a gas-liquid abrasive particle flow joint, an abrasive particle inflow opening valve, a runner joint, a hollow runner, a rotary joint, a flange plate, a rotary driving motor, a rotary driving wheel, a rotary driven wheel, a rotary synchronous belt, an annular electric slip ring, an electric slip ring fixing seat, an electric slip ring stator end wire, a slip ring rotor end wire, a conductive copper ring and a main clamping end O-shaped ring, wherein the sliding rail connecting plate is vertically arranged on a vertical sliding block of a vertical linear module, the runner fixing plate is fixedly arranged on the sliding rail connecting plate, the rotary joint fixing seat and the electric slip ring fixing seat are fixedly arranged on the runner fixing plate, the rotary joint is arranged on the rotary joint fixing seat, and the axial lead of the rotary joint is parallel to the axial lead of the rotary driven plate when the rotary joint is arranged; one end of the rotary joint, which is close to the rotary magnetic field module, is a rotary end of the rotary joint, one end of the hollow runner is fixedly connected with the rotary end of the rotary joint, a flange plate is sleeved at the other end of the hollow runner, the rotary clamping head is arranged on the flange plate and is opposite to an installation inclined plane of the rotary runner device, the axial lead of the rotary clamping head is perpendicular to the installation inclined plane, and the axial lead of the hollow runner is parallel to the axial leads of the rotary driven plate and the rotary clamping head when the hollow runner is arranged; the annular electric slip ring is arranged on the electric slip ring fixing seat and sleeved on the hollow runner; the annular over-voltage slip ring is connected with the other input line of the external square wave alternating current power supply through an electric slip ring stator end lead; the hollow runner is provided with a first rotor wire groove, the first rotor wire groove extends to the end face of one end of a hollow runner connecting flange plate along the outer wall of the hollow runner, the flange plate is provided with a second rotor wire groove, one end of the second rotor wire groove is communicated with the first rotor wire groove on the hollow runner, the other end of the second rotor wire groove extends to the end face of the flange plate, which is used for clamping one end of a workpiece to be processed, a conductive copper ring is arranged on the end face of the flange plate, which is used for clamping one end of the workpiece to be processed, a slip ring rotor end wire is embedded in the first rotor wire groove and the second rotor wire groove, one end of the slip ring rotor end wire is attached to an annular electric slip ring, and the other end of the slip ring rotor end wire is connected with a conductive copper ring; the two ends of the workpiece to be processed are clamped through the rotary clamping head and the rotary driven disc respectively, a blind hole of the workpiece to be processed is positioned at one end of the rotary clamping head, and the conductive copper ring is attached to the workpiece to be processed when the workpiece to be processed is clamped on the rotary clamping head; the other end of rotary joint is rotary joint's stiff end, and rotary joint's stiff end passes through runner joint and connects gas-liquid abrasive grain stream joint, gas-liquid abrasive grain stream joint is provided with three access & exit, is abrasive grain inflow end, abrasive grain outflow end and bleed end respectively, and abrasive grain inflow end, abrasive grain outflow end and bleed end intercommunication each other, and the runner joint is connected to gas-liquid abrasive grain stream joint's abrasive grain outflow end, and gas-liquid abrasive grain stream joint's abrasive grain inflow end passes through abrasive grain inflow port valve and abrasive grain flow pipeline and connects external liquid metal abrasive grain stream generating device, the abrasive grain stream that liquid metal abrasive grain stream generating device produced is liquid metal abrasive grain stream, and gas-liquid abrasive grain stream joint's bleed end passes through bleed port check valve and bleed pipeline and connects external bleed device, gas-liquid abrasive grain stream joint, runner joint, hollow runner and rotatory clamping head constitute rotatory runner device's runner part jointly, and gas-liquid abrasive grain stream joint, runner joint, hollow runner and rotatory clamping head's height reduces in proper order.

Further, the rotary clamping head comprises a flange-shaped fixed flange end and a main mounting end for fixing a workpiece to be machined, the fixed flange end of the rotary clamping head is fixedly connected with the flange plate, a workpiece mounting main groove matched with the machining end of the workpiece to be machined in shape is formed in the main mounting end of the rotary clamping head, the machining end of the workpiece to be machined is mounted in the workpiece mounting main groove, a main clamping end O-shaped ring for preventing the machining end of the workpiece to be machined from sliding is arranged in the workpiece mounting main groove of the rotary clamping head, an inner ring of the main clamping end O-shaped ring is attached to and sleeved on the machining end of the workpiece to be machined, and an outer ring of the main clamping end O-shaped ring is attached to the inner wall of the workpiece mounting main groove; the rotary driven plate comprises a cylindrical fixed end and a secondary installation end used for fixing a workpiece to be machined, the fixed end of the rotary driven plate is fixed in a circular groove of the supporting block, a workpiece installation secondary groove matched with the rear end of the workpiece to be machined is formed in the secondary installation end of the rotary driven plate, the rear end of the workpiece to be machined is installed in the workpiece installation secondary groove, a secondary clamping end O-shaped ring used for preventing the workpiece to be machined from sliding is arranged at the bottom of the workpiece installation secondary groove of the rotary driven plate, an inner ring of the secondary clamping end O-shaped ring is attached to and sleeved on the rear end of the workpiece to be machined, an outer ring of the secondary clamping end O-shaped ring is attached to the inner wall of the workpiece installation secondary groove, and the conductive copper ring is arranged on the inner wall of the primary clamping end O-shaped ring and is arranged on the inner wall of the secondary clamping end O-shaped ring.

Further, the horizontal linear module is fixed on the horizontal module mounting frame through bolts, the horizontal module mounting frame is fixed on the workbench through bolts, and the vertical linear module is fixed on the horizontal sliding block of the horizontal linear module through bolts. One end of the horizontal linear module is provided with four bolt holes, the horizontal module driving motor is provided with four bolt holes matched with the bolt holes on the horizontal linear module, and the horizontal linear module is fixed through four fixing bolts penetrating through the bolt holes.

Further, the gas-liquid abrasive particle flow connector is a square connector, and the gas-liquid abrasive particle flow connector is fixed on the sliding rail connecting plate.

Further, the rotary joint fixing seat comprises a runner fixing base and a runner fixing upper seat, arc grooves matched with the hollow runner are formed in the runner fixing base and the runner fixing upper seat, the runner fixing base and the runner fixing upper seat clamp the hollow runner together, and the runner fixing base and the runner fixing upper seat are fixedly connected through bolts.

Furthermore, the axial lead of the hollow runner and the axial lead of the fixed end of the rotary driven disc are inclined at an angle of 30-60 degrees with the horizontal plane, and the axial lead of the hollow runner and the axial lead of the fixed end of the rotary driven disc are perpendicular to the installation inclined plane of the supporting block.

Further, the supporting block is a right-angle triangular prism-shaped supporting block, two right-angle faces and an installation inclined plane are arranged on the supporting block, the right-angle faces of the supporting block are fixedly arranged on the workbench, and the rotary driven disc is arranged on the installation inclined plane of the supporting block through the turntable base.

Further, the liquid metal abrasive particle flow is formed by mixing liquid metal and loose abrasive particles, and the liquid metal is liquid gallium.

Furthermore, the air extracting device is an air extracting pump, and the hollow runner is a hollow shaft.

Further, the middle part of hollow runner is provided with the middle part location installation screw thread that is used for installing annular electric sliding ring excessively, the one end that hollow runner is close to rotary joint is provided with the tail end location installation screw thread that is used for connecting rotary joint, the one end that hollow runner is close to the ring flange is provided with the boss that is used for connecting the ring flange. The two ends of the hollow runner are connected with the flange plate and the rotary joint in a sealing way.

Further, the horizontal linear module and the vertical linear module are screw modules composed of a base, a linear guide rail, a ball screw, a screw nut, a sliding block and a bearing seat.

A negative pressure polishing method for polishing a blind hole of a conductive workpiece based on a negative pressure polishing device for polishing the blind hole of the conductive workpiece specifically comprises the following steps:

Step one: the bottom end of a workpiece to be processed is arranged on a rotary driven disc through an auxiliary clamping end O-shaped ring;

step two: starting a vertical module driving motor, and driving a rotary clamping head to move downwards by driving a vertical sliding block on a vertical linear module to move downwards, so that the rotary clamping head is close to a workpiece to be processed on a rotary driven disc;

step three: starting a horizontal module driving motor, driving a rotary clamping head to move towards a workpiece to be processed in the horizontal direction by driving the horizontal sliding block on the horizontal linear module to horizontally move, and stopping the horizontal module driving motor when the position is reached;

step four: repeating the second step and the third step, so that the workpiece to be processed and the rotary clamping head are gradually close until the processing end of the workpiece to be processed completely stretches into the rotary clamping head, and the main clamping end O-shaped ring in the rotary clamping head is completely sleeved on the processing end of the workpiece to be processed, at the moment, the workpiece to be processed is clamped by the rotary clamping head and the rotary driven disc together, and the blind hole of the workpiece to be processed is communicated with the hollow runner;

step five: closing the abrasive grain inflow port valve, opening the extraction port one-way valve and starting the extraction device, and connecting the extraction device through an extraction pipeline by using the extraction port one-way valve to extract air, so that the blind hole of the workpiece to be processed and the interior of the hollow runner are in a negative pressure state;

Step six: the method comprises the steps that after the inside of a blind hole of a workpiece to be processed is in a negative pressure state, an air extractor is closed, and because an air extraction hole one-way valve only allows air to flow in one direction, the inside of the blind hole of the workpiece to be processed is always in the negative pressure state, at the moment, an abrasive grain inflow port valve is opened, and a liquid metal abrasive grain flow generating device is started, so that liquid metal abrasive grain flow generated in the liquid metal abrasive grain flow generating device sequentially flows through the abrasive grain inflow port valve, an air-liquid abrasive grain flow joint, a runner joint and a rotary joint to enter a hollow runner, and because the blind hole and the hollow runner of the workpiece to be processed are in the negative pressure state, the liquid metal abrasive grain flow can directly flow into the blind hole of the workpiece to be processed;

step seven: after the liquid metal abrasive particle flow is injected, the abrasive particle inflow port valve is closed, the rotary driving motor is opened, and the rotary driving motor drives the movable end of the rotary joint, the hollow runner, the flange plate, the rotary clamping head and the whole body formed by the workpiece to be processed to rotate through a synchronous belt mechanism formed by the rotary driving wheel, the rotary driven wheel and the rotary synchronous belt;

step eight: a sinusoidal alternating current power supply connected with the three-phase stator coil is turned on, and as the three-phase stator coil can generate a rotating magnetic field under an alternating current electric field, the rotating magnetic field generated by the three-phase stator coil during operation drives metal particles in the liquid metal polishing solution to move, so that abrasive particles in the liquid metal polishing solution are accelerated to rotate and impact blind holes of a workpiece to be processed;

Step nine: an external square wave alternating current power supply is turned on, square wave alternating current is applied to the workpiece to be processed through a closed loop formed by the annular electric slip ring, a slip ring rotor end lead, a conductive copper sheet, the workpiece to be processed, the conductive copper ring and the flange type electric slip ring, an alternating current electric field is formed inside the workpiece to be processed under the action of the square wave alternating current, and under the action of the alternating current electric field, metal particles in the liquid metal abrasive particle flow can carry out reciprocating oscillation along the axial direction of the blind hole, so that the abrasive particle movement in the liquid metal abrasive particle flow is disordered, and the blind hole polishing of the workpiece to be processed is further accelerated until the blind hole polishing of the workpiece to be processed is completed.

Furthermore, in the eighth step, the rotation speed and the intensity of the rotating magnetic field generated by the three-phase stator coil are controlled by adjusting the frequency and the voltage of an externally connected sinusoidal alternating current power supply, so that the change of the movement condition of metal particles in the liquid metal polishing solution is realized, and the change of the polishing efficiency is further realized.

The invention has the beneficial effects that:

1. according to the invention, the blind holes of the blind hole type workpiece can be polished, and the blind holes of the workpiece to be polished are in a negative pressure state by exhausting, so that abrasive particle flows can smoothly enter the blind holes.

2. The abrasive particle flow used in the invention is liquid metal abrasive particle flow, metal particles in the liquid metal abrasive particle flow can form good contact with the surface of a workpiece to be processed under the action of a rotating magnetic field generated by the three-phase stator coil, and micro cutting is carried out, so that the surface of a blind hole of the workpiece to be processed can not generate mechanical deformation; the polishing efficiency is faster, the effect is better, micro cutting is performed, and mechanical deformation of the surface of the workpiece is avoided.

3. According to the invention, the orifice of the workpiece to be processed is inclined upwards, so that abrasive particle flow in the polishing process is gathered in the blind hole, turbulent flow is generated by the adopted liquid metal abrasive particle flow under the rotating magnetic field, compared with the traditional medium water and oil, the liquid metal has the characteristics of high density, good flow controllability and the like, the fluidity of the liquid metal is closely related to the electric field and the magnetic field around the liquid metal, the flowing state of the liquid metal can be controlled by changing the magnetic field, different treatment modes can be carried out on the conductor and non-conductor type workpiece, and the application range is wide.

4. The invention adopts the liquid metal abrasive particle flow for processing, the melting point of the liquid metal abrasive particle flow is lower and can be controlled to be 8-29 ℃, meanwhile, the boiling point of the liquid metal abrasive particle flow is higher than 2000 ℃, the gasification can be avoided, the fluid management is convenient, and the liquid metal abrasive particle flow is nonflammable and nontoxic, and the safety is higher; meanwhile, after the liquid metal abrasive particle flow is used, the liquid metal abrasive particle flow can be separated through an electromagnetic purification technology, so that the later recovery of the liquid metal abrasive particle flow is realized, and the energy is saved.

5. The polishing method has the advantages that less abrasive particle flow is needed in the polishing process, and the abrasive particle flow is nontoxic, high in safety, small in pollution and environment-friendly.

6. The invention uses the movable positioning module formed by the horizontal linear module and the vertical linear module to carry out movable positioning, and can quickly and accurately realize accurate positioning in space.

7. The invention discloses a rotary runner assembly, which can work under a relatively severe polishing environment through synchronous pulley and synchronous belt transmission.

8. According to the invention, the workpiece to be processed is obliquely arranged on the right-angle triangular prism-shaped supporting block, and the blind hole of the workpiece to be processed has a certain inclination angle, so that the movement of abrasive particle flow entering the blind hole during polishing is more disordered, and the polishing effect is better.

9. When the polishing device is used for polishing, the workpiece to be processed can mechanically rotate under the drive of the rotary driving motor, so that the liquid metal abrasive particle flow in the blind hole of the workpiece to be processed and the blind hole of the workpiece to be processed generate relative displacement, the polishing effect is better, and the efficiency is faster.

10. The rotary clamping head and the rotary driven disc are used for clamping the workpiece to be processed, can be conveniently disassembled and assembled, can be designed and replaced according to the actual condition of the workpiece during processing, do not need to carry out other changes on the whole device, and have strong practicability.

Drawings

Fig. 1 is a schematic diagram of the overall structure of a negative pressure polishing device for polishing blind holes of a conductive workpiece according to the present invention.

Fig. 2 is a schematic structural view of the mobile positioning device of the present invention.

Fig. 3 is a schematic view of the construction of the rotary flow path device of the present invention.

Fig. 4 is a schematic view of a flow path partially in section of a rotary flow path device according to the present invention.

Fig. 5 is a schematic structural view of the hollow runner of the present invention.

Fig. 6 is a schematic cross-sectional view of a rotary clamping head of the present invention.

Fig. 7 is a schematic view of the overall structure of the rotating magnetic field assembly of the present invention.

FIG. 8 is a schematic cross-sectional view of a rotating field assembly of the present invention.

Fig. 9 is a schematic diagram of the mounting mechanism of the rotary driven disc and the flange-type over-electrical slip ring on the rotary magnetic field assembly of the present invention.

In the drawing the view of the figure, 1-moving positioning device, 2-rotating runner device, 3-rotating magnetic field device, 4-workpiece to be polished, 5-workbench, 101-horizontal module mounting frame, 102-horizontal linear module, 103-horizontal slide block, 104-vertical slide block, 105-vertical module driving motor, 106-vertical linear module, 107-horizontal module driving motor, 201-rotating clamping head, 202-hollow runner, 203-electric slip ring fixing seat, 204-electric slip ring stator end wire, 205-sliding rail connecting plate, 206-rotating joint fixing seat, 207-runner fixing plate, 208-gas-liquid abrasive particle flow joint, 209-abrasive particle inflow valve, 210-pumping port one-way valve, 211-runner joint, and 212-rotary joint, 213-annular over-electric slip ring, 214-rotary driving motor, 215-rotary motor fixing plate, 216-rotary synchronous belt, 217-rotary driven wheel, 218-positioning nut, 219-flange, 220-positioning nut mounting screw thread, 221-slip ring rotor end wire, 222-main clamping end O-shaped ring, 223-conductive copper ring, 224-rotary driving wheel, 301-supporting block, 302-three-phase stator coil, 303-stator coil fixing seat, 304-rotary driven plate, 305-driven plate end O-shaped ring, 306-flange-type over-electric slip ring, 307-conductive copper sheet, 308-over-electric slip ring rotor end wire, 309-over-electric slip ring stator end wire and 310-circular groove.

Detailed Description

The invention is further described below with reference to the accompanying drawings:

as shown in fig. 1 to 9, a negative pressure polishing device for polishing blind holes of conductive workpieces comprises a workbench 5, a movable positioning device 1, a rotary runner device 2 and a rotary magnetic field device 3, wherein the movable positioning device 1 is arranged on the workbench 5, the rotary runner device 2 is arranged on the movable positioning device 1, and the rotary magnetic field device 3 is fixed on the workbench 5 obliquely below the rotary runner device 2.

The mobile positioning device 1 comprises a horizontal module mounting frame 101, a horizontal linear module 102, a horizontal module driving motor 107, a vertical linear module 106 and a vertical module driving motor 105, wherein the horizontal module mounting frame 101 is fixed on a workbench 5; the horizontal linear module 102 is horizontally fixed on the horizontal module mounting frame 101, the horizontal module driving motor 107 is fixed at one end of the horizontal linear module 102, and a driving shaft of the horizontal module driving motor 107 is connected with the horizontal linear module 102 and drives the horizontal sliding block 103 on the horizontal linear module 102 to do linear motion along the horizontal direction; the vertical linear module 106 is vertically fixed on the horizontal sliding block 103 of the horizontal linear module 102, the vertical module driving motor 105 is fixed at the upper end of the vertical linear module 106, and a driving shaft of the vertical module driving motor 105 is connected with the vertical linear module 106 and drives the vertical sliding block 104 on the vertical linear module 106 to do linear motion along the vertical direction; the rotary runner device 2 is arranged on a vertical sliding block 104 of a vertical linear module 106, and the rotary magnetic field device 3 is arranged on a workbench 5 beside the horizontal module mounting frame 101; the rotating magnetic field device 3 and the rotating runner device 2 are arranged on the same side of the vertical slider 104.

The rotating magnetic field device 3 comprises a supporting block 301, a rotating driven plate 304, a three-phase stator coil 302, a flange-type over-current slip ring 306, a conductive copper sheet 307 and a stator coil fixing seat 303, wherein the supporting block 301 is fixed on the workbench 5, and an installation inclined surface which is inclined upwards is arranged on the supporting block 301; the mounting inclined plane is provided with a circular groove 310 for mounting the stator coil fixing seat 303 and an electric slip ring mounting groove for mounting the flange type electric slip ring 306; the electric slip ring mounting groove is arranged coaxially with the circular groove 310, the electric slip ring mounting groove is arranged inside the circular groove 310, the stator coil fixing seat 303 is embedded in the circular groove 310 of the mounting inclined plane, the flange type electric slip ring 306 is embedded in the electric slip ring mounting groove of the inclined plane, the stator end of the flange type electric slip ring 306 is fixedly arranged in the electric slip ring mounting groove, and the rotor end of the flange type electric slip ring 306 is fixedly connected with the fixed end of the rotary driven disc 304; the rotary driven plate 304 is provided with a workpiece mounting groove, the inner wall of the workpiece mounting groove of the rotary driven plate 304 is provided with a conductive copper sheet 307, the conductive copper sheet 307 is connected with a lead wire at the rotor end of the flange type electric slip ring 306, and the lead wire at the stator end of the flange type electric slip ring 306 is connected with one input wire of an external square wave alternating current power supply; the three-phase stator coil 302 is fixed on a stator coil fixing seat 303, and the three-phase stator coil 302 is arranged around the whole rotary driven disc 304; the input terminals of the three-phase stator coil 302 are connected to an external sinusoidal ac power source.

The rotary runner device 2 comprises a rotary clamping head 201, a rotary joint 212, a rotary joint fixing seat 206, a runner fixing plate 207, a sliding rail connecting plate 205, an extraction opening one-way valve 210, a gas-liquid abrasive particle flow joint 208, an abrasive particle inflow opening valve 209, a runner joint 211, a hollow runner 202, the rotary joint 212, a flange 219, a rotary driving motor 214, a rotary driving wheel 224, a rotary driven wheel 217, a rotary synchronous belt 216, an annular electric slip ring 213, an electric slip ring fixing seat 203, an electric slip ring stator end wire 204, a slip ring rotor end wire 221, a conductive copper ring 223 and a main clamping end O-shaped ring 222, wherein the sliding rail connecting plate 205 is vertically arranged on a vertical sliding block 104 of a vertical linear module 106, the runner fixing plate 207 is fixedly arranged on the sliding rail connecting plate 205, the rotary joint fixing seat 206 and the electric slip ring fixing seat 203 are fixedly arranged on the runner fixing plate 207, the rotary joint 212 is arranged on the rotary joint fixing seat 206, and when the rotary joint 212 is arranged, the axial lead of the rotary joint 212 is parallel to the axial lead of a rotary driven disc 304; one end of the rotary joint 212, which is close to the rotary magnetic field module, is a rotary end of the rotary joint 212, one end of the hollow runner 202 is fixedly connected with the rotary end of the rotary joint 212, a flange 219 is sleeved at the other end of the hollow runner 202, a rotary clamping head 201 is arranged on the flange 219, the rotary clamping head 201 is opposite to an installation inclined plane of the rotary runner device 2, an axial lead of the rotary clamping head 201 is arranged vertically to the installation inclined plane, and the axial lead of the runner 202 is parallel to the axial leads of the rotary driven plate 304 and the rotary clamping head 201 when the hollow runner 202 is installed; the annular electric slip ring 213 is arranged on the electric slip ring fixing seat 203, and the annular electric slip ring 213 is sleeved on the hollow runner 202; the annular over-electric slip ring 213 is connected with the other input line of the external square wave alternating current power supply through an electric slip ring stator end lead 204; the hollow runner 202 is provided with a first rotor wire groove, the first rotor wire groove extends to the end face of one end of the hollow runner 202, which is connected with the flange 219, along the outer wall of the hollow runner 202, the flange 219 is provided with a second rotor wire groove, one end of the second rotor wire groove is communicated with the first rotor wire groove on the hollow runner 202, the other end of the second rotor wire groove extends to the end face of the flange 219, which is used for clamping one end of a workpiece to be processed, the conductive copper ring 223 is arranged on the end face of the flange 219, which is used for clamping the workpiece to be processed, the slip ring rotor end wire 221 is embedded in the first rotor wire groove and the second rotor wire groove, one end of the slip ring rotor end wire 221 is attached to the annular over-current slip ring 213, and the other end of the slip ring rotor end wire 221 is connected with the conductive copper ring 223; the two ends of the workpiece to be processed are respectively clamped by the rotary clamping head 201 and the rotary driven disc 304, a blind hole of the workpiece to be processed is positioned at one end of the rotary clamping head 201, and the conductive copper ring 223 is attached to the workpiece to be processed when the workpiece to be processed is clamped on the rotary clamping head 201; the other end of the rotary joint 212 is a fixed end of the rotary joint 212, the fixed end of the rotary joint 212 is connected with a gas-liquid abrasive particle flow joint 208 through a runner joint 211, the gas-liquid abrasive particle flow joint 208 is provided with three inlets and outlets which are an abrasive particle inflow port end, an abrasive particle outflow port end and an air extraction port end respectively, the abrasive particle inflow port end, the abrasive particle outflow port end and the air extraction port end are mutually communicated, the abrasive particle outflow port end of the gas-liquid abrasive particle flow joint 208 is connected with the runner joint 211, the abrasive particle inflow port end of the gas-liquid abrasive particle flow joint 208 is connected with an external liquid metal abrasive particle flow generating device through an abrasive particle inflow port valve 209 and an abrasive particle flow pipeline, the air extraction port end of the gas-liquid abrasive particle flow joint 208 is connected with an external air extraction device through an air extraction port one-way valve 210 and an air extraction pipeline, the gas-liquid abrasive particle flow joint 208, the runner joint 211, the hollow runner 202 and the rotary clamping head 201 jointly form a runner part of the rotary runner device, and the heights of the gas-liquid abrasive particle flow joint 208, the runner joint 211, the hollow runner and the rotary clamping head 201 are sequentially reduced.

The rotary clamping head 201 comprises a flange-shaped fixed flange end and a main mounting end for fixing a workpiece to be machined, the fixed flange end of the rotary clamping head 201 is fixedly connected with the flange 219, a workpiece mounting main groove matched with the machining end of the workpiece to be machined is formed in the main mounting end of the rotary clamping head 201, the machining end of the workpiece to be machined is mounted in the workpiece mounting main groove, a main clamping end O-shaped ring 222 for preventing the machining end of the workpiece to be machined from sliding is arranged in the workpiece mounting main groove of the rotary clamping head 201, the inner ring of the main clamping end O-shaped ring 222 is attached to and sleeved on the machining end of the workpiece to be machined, and the outer ring of the main clamping end O-shaped ring 222 is attached to the inner wall of the workpiece mounting main groove; the rotary driven plate 304 comprises a cylindrical fixed end and a secondary installation end for fixing a workpiece to be processed, the fixed end of the rotary driven plate 304 is fixed in a circular groove 310 of the supporting block 301, a workpiece installation secondary groove matched with the rear end of the workpiece to be processed is formed in the secondary installation end of the rotary driven plate 304, the rear end of the workpiece to be processed is installed in the workpiece installation secondary groove, a secondary clamping end O-shaped ring for preventing the workpiece to be processed from sliding is arranged at the bottom of the workpiece installation secondary groove of the rotary driven plate 304, an inner ring of the secondary clamping end O-shaped ring is attached to and sleeved on the rear end of the workpiece to be processed, an outer ring of the secondary clamping end O-shaped ring is attached to the inner wall of the workpiece installation secondary groove, the conductive copper ring 223 is arranged on the inner wall of the primary clamping end O-shaped ring 222, and the conductive copper sheet 307 is arranged on the inner wall of the secondary clamping end O-shaped ring.

The horizontal linear module 102 is fixed on the horizontal module mounting frame 101 by bolts, the horizontal module mounting frame 101 is fixed on the workbench 5 by bolts, and the vertical linear module 106 is fixed on the horizontal slider 103 of the horizontal linear module 102 by bolts. .

The gas-liquid abrasive particle flow joint 208 is a square joint, and the gas-liquid abrasive particle flow joint 208 is fixed on the slide rail connecting plate 205.

The rotary joint fixing seat 206 comprises a runner fixing base and a runner fixing upper seat, arc-shaped grooves matched with the hollow runner 202 are formed in the runner fixing base and the runner fixing upper seat, the hollow runner 202 is clamped by the runner fixing base and the runner fixing upper seat together, and the runner fixing base and the runner fixing upper seat are fixedly connected through bolts.

The axis of the hollow runner 202 and the axis of the fixed end of the rotary driven plate 304 are inclined at an angle of 30-60 degrees with respect to the horizontal plane, and the axis of the hollow runner 202 and the axis of the fixed end of the rotary driven plate 304 are perpendicular to the installation inclined plane of the supporting block 301.

The supporting block 301 is a right-angle triangular prism-shaped supporting block 301, two right-angle faces and an installation inclined face are arranged on the supporting block 301, the right-angle faces of the supporting block 301 are fixedly installed on the workbench 5, and the rotary driven plate 304 is installed on the installation inclined face of the supporting block through the turntable base. .

The middle part of hollow runner 202 is provided with the middle part location installation screw thread that is used for installing annular too much electric sliding ring 213, the one end that hollow runner 202 is close to rotary joint 212 is provided with the tail end location installation screw thread that is used for connecting rotary joint 212, the one end that hollow runner 202 is close to ring flange 219 is provided with the boss that is used for connecting ring flange 219. The hollow flow passage 202 is connected at both ends thereof with the flange 219 and the rotary joint 212 in a sealing manner.

step one: the bottom end of a workpiece to be processed is arranged on a rotary driven disc 304 through a secondary clamping end O-shaped ring;

step two: starting a vertical module driving motor 105, and driving a rotary clamping head 201 to move downwards by driving a vertical sliding block 104 on a vertical linear module 106 to move downwards in a linear manner, so that the rotary clamping head 201 is close to a workpiece to be processed on a rotary driven disc 304;

step three: starting a horizontal module driving motor 107, driving a rotary clamping head 201 to move in the horizontal direction towards the direction of a workpiece to be processed by driving the horizontal sliding block 103 on the horizontal linear module 102 to horizontally move, and stopping the horizontal module driving motor 107 after the position reaches a proper position;

Step four: repeating the second and third steps, gradually approaching the workpiece to be processed and the rotary clamping head 201 until the processing end of the workpiece to be processed completely stretches into the rotary clamping head 201, and completely sleeving the main clamping end O-shaped ring 222 in the rotary clamping head 201 on the processing end of the workpiece to be processed, wherein the workpiece to be processed is clamped by the rotary clamping head 201 and the rotary driven disc 304 together at the moment, and the blind hole of the workpiece to be processed is communicated with the hollow runner 202;

step five: closing the abrasive grain inflow port valve 209, opening the extraction port one-way valve 210 and starting the air extractor, and connecting the air extractor with the extraction port one-way valve 210 through an air extraction pipeline to extract air, so that the blind hole of the workpiece to be processed and the interior of the hollow runner 202 are in a negative pressure state;

step six: after the inside of the blind hole of the workpiece to be processed is in a negative pressure state, the air extractor is closed, and the air extraction port one-way valve 210 only allows the air to flow in one direction, so that the inside of the blind hole of the workpiece to be processed is always in a negative pressure state, at the moment, the abrasive grain inflow port valve 209 is opened, and the liquid metal abrasive grain flow generating device is started, so that the liquid metal abrasive grain flow generated in the liquid metal abrasive grain flow generating device sequentially flows through the abrasive grain inflow port valve 209, the air-liquid abrasive grain flow joint 208, the flow passage joint 211 and the rotary joint 212 to enter the hollow flow passage 202, and the blind hole of the workpiece to be processed and the hollow flow passage 202 are both in a negative pressure state, and the liquid metal abrasive grain flow can directly flow into the blind hole of the workpiece to be processed;

Step seven: after the liquid metal abrasive particle flow is injected, the abrasive particle inflow port valve 209 is closed, the rotary driving motor 214 is opened, and the rotary driving motor 214 drives the movable end of the rotary joint 212, the hollow runner 202, the flange 219, the rotary clamping head 201 and the whole body formed by the workpiece to be processed to rotate through a synchronous belt mechanism formed by the rotary driving wheel 224, the rotary driven wheel 217 and the rotary synchronous belt 216;

step eight: a sinusoidal alternating current power supply connected with the three-phase stator coil 302 is turned on, and as the three-phase stator coil generates a rotating magnetic field under an alternating current electric field, the rotating magnetic field generated by the three-phase stator coil 302 during operation drives metal particles in the liquid metal polishing solution to move, so that abrasive particles in the liquid metal polishing solution are accelerated to rotate and impact blind holes of a workpiece to be processed;

step nine: an external square wave alternating current power supply is turned on, square wave alternating current is applied to the workpiece to be processed through a closed loop formed by the annular electric slip ring 213, the slip ring rotor end lead 221, the conductive copper sheet 307, the workpiece to be processed, the conductive copper ring 223 and the flange type electric slip ring 306, an alternating current electric field is formed inside the workpiece to be processed under the action of the square wave alternating current, and under the action of the alternating current electric field, metal particles in the liquid metal abrasive particle flow can carry out reciprocating oscillation along the axial direction of the blind hole, so that the abrasive particle movement in the liquid metal abrasive particle flow is disordered, and the blind hole polishing of the workpiece to be processed is further accelerated until the blind hole polishing of the workpiece to be processed is completed.

In the eighth step, the rotation speed and the intensity of the rotating magnetic field generated by the three-phase stator coil 302 are controlled by adjusting the frequency and the voltage of an external sinusoidal alternating current power supply, so that the change of the movement condition of metal particles in the liquid metal polishing solution is realized, and the change of the polishing efficiency is further realized.

The above embodiments are only preferred embodiments of the present invention, and are not limiting to the technical solutions of the present invention, and any technical solution that can be implemented on the basis of the above embodiments without inventive effort should be considered as falling within the scope of protection of the patent claims of the present invention.

Claims

1. A negative pressure burnishing device for electrically conductive work piece blind hole is polished, its characterized in that: the device comprises a workbench (5), a mobile positioning device (1), a rotary runner device (2) and a rotary magnetic field device (3), wherein the mobile positioning device (1) is arranged on the workbench (5), the rotary runner device (2) is arranged on the mobile positioning device (1), and the rotary magnetic field device (3) is fixed on the workbench (5) obliquely below the rotary runner device (2);

the mobile positioning device (1) comprises a horizontal module mounting frame (101), a horizontal linear module (102), a horizontal module driving motor (107), a vertical linear module (106) and a vertical module driving motor (105), wherein the horizontal module mounting frame (101) is fixed on a workbench (5); the horizontal linear module (102) is horizontally fixed on the horizontal module mounting frame (101), the horizontal module driving motor (107) is fixed at one end of the horizontal linear module (102), and a driving shaft of the horizontal module driving motor (107) is connected with the horizontal linear module (102) and drives a horizontal sliding block (103) on the horizontal linear module (102) to do linear motion along the horizontal direction; the vertical linear module (106) is vertically fixed on a horizontal sliding block (103) of the horizontal linear module (102), a vertical module driving motor (105) is fixed at the upper end of the vertical linear module (106), and a driving shaft of the vertical module driving motor (105) is connected with the vertical linear module (106) and drives a vertical sliding block (104) on the vertical linear module (106) to do linear motion along the vertical direction; the rotary runner device (2) is arranged on a vertical sliding block (104) of the vertical linear module (106), and the rotary magnetic field device (3) is arranged on a workbench (5) beside the horizontal module mounting frame (101); the rotating magnetic field device (3) and the rotating runner device (2) are arranged on the same side of the vertical sliding block (104);

The rotating magnetic field device (3) comprises a supporting block (301), a rotating driven disc (304), a three-phase stator coil (302), a flange-type over-electricity slip ring (306), a conductive copper sheet (307) and a stator coil fixing seat (303), wherein the supporting block (301) is fixed on a workbench (5), and an installation inclined plane which is inclined upwards is arranged on the supporting block (301); the mounting inclined plane is provided with a circular groove (310) for mounting the stator coil fixing seat (303) and an electric slip ring mounting groove for mounting the flange type electric slip ring (306); the electric slip ring mounting groove is arranged on the same axis as the circular groove (310), the electric slip ring mounting groove is arranged inside the circular groove (310), the stator coil fixing seat (303) is embedded in the circular groove (310) of the mounting inclined plane, the flange type electric slip ring (306) is embedded in the electric slip ring mounting groove of the inclined plane, the stator end of the flange type electric slip ring (306) is fixedly arranged in the electric slip ring mounting groove, and the rotor end of the flange type electric slip ring (306) is fixedly connected with the fixed end of the rotary driven disc (304); a workpiece mounting groove is formed in the rotary driven disc (304), a conductive copper sheet (307) is arranged on the inner wall of the workpiece mounting groove of the rotary driven disc (304), the conductive copper sheet (307) is connected with a lead wire at the rotor end of the flange type electric slip ring (306), and a lead wire at the stator end of the flange type electric slip ring (306) is connected with an input wire of an external square wave alternating current power supply; the three-phase stator coil (302) is fixed on the stator coil fixing seat (303), and the three-phase stator coil (302) is arranged around the whole rotary driven disc (304); the input end of the three-phase stator coil (302) is connected with an external sine alternating current power supply;

The rotary runner device (2) comprises a rotary clamping head (201), a rotary joint (212), a rotary joint fixing seat (206), a runner fixing plate (207), a sliding rail connecting plate (205), an extraction opening one-way valve (210), a gas-liquid abrasive particle flow joint (208), an abrasive particle flow inlet valve (209), a runner joint (211), a hollow runner (202), the rotary joint (212), a flange plate (219), a rotary driving motor (214), a rotary driving wheel (224), a rotary driven wheel (217), a rotary synchronous belt (216), an annular electric slip ring (213), an electric slip ring fixing seat (203), an electric slip ring stator end wire (204), a slip ring rotor end wire (221), a conductive copper ring (223) and a main clamping end O-shaped ring (222), the sliding rail connecting plate (205) is vertically arranged on a vertical sliding block (104) of a vertical linear module (106), the runner fixing plate (207) is fixedly arranged on the sliding rail connecting plate (205), the rotary joint fixing seat (206) and the electric slip ring fixing seat (203) are fixedly arranged on the runner fixing plate (207), the rotary joint (212) is arranged on the rotary joint fixing seat (206), when the rotary joint (212) is installed, the axial line of the rotary joint (212) is parallel to the axial line of the rotary driven disc (304); one end of the rotary joint (212) close to the rotary magnetic field module is a rotary end of the rotary joint (212), one end of the hollow runner (202) is fixedly connected with the rotary end of the rotary joint (212), the other end of the hollow runner (202) is sleeved with a flange plate (219), the rotary clamping head (201) is arranged on the flange plate (219), the rotary clamping head (201) is opposite to an installation inclined plane of the rotary runner device (2), the axial lead of the rotary clamping head (201) is perpendicular to the installation inclined plane, and the axial lead of the hollow runner (202) is parallel to the axial leads of the rotary driven plate (304) and the rotary clamping head (201) during installation of the hollow runner (202); the annular electric slip ring (213) is arranged on the electric slip ring fixing seat (203), and the annular electric slip ring (213) is sleeved on the hollow runner (202); the annular over-electric slip ring (213) is connected with the other input line of the external square wave alternating current power supply through an electric slip ring stator end lead (204); the hollow runner (202) is provided with a first rotor wire groove, the first rotor wire groove extends to the end face of one end of the hollow runner (202) connected with the flange plate (219) along the outer wall of the hollow runner (202), the flange plate (219) is provided with a second rotor wire groove, one end of the second rotor wire groove is communicated with the first rotor wire groove on the hollow runner (202), the other end of the second rotor wire groove extends to the end face of the flange plate (219) for clamping one end of a workpiece to be machined, the conductive copper ring (223) is installed at one end of the flange plate (219) for clamping the workpiece to be machined, the sliding ring rotor end wire (221) is embedded in the first rotor wire groove and the second rotor wire groove, one end of the sliding ring rotor end wire (221) is attached to the annular overcurrent sliding ring (213), and the other end of the sliding ring rotor end wire (221) is connected with the conductive copper ring (223); the two ends of the workpiece to be processed are respectively clamped by the rotary clamping head (201) and the rotary driven disc (304), a blind hole of the workpiece to be processed is positioned at one end of the rotary clamping head (201), and the conductive copper ring (223) is attached to the workpiece to be processed when the workpiece to be processed is clamped on the rotary clamping head (201); the other end of the rotary joint (212) is a fixed end of the rotary joint (212), the fixed end of the rotary joint (212) is connected with a gas-liquid abrasive particle flow joint (208) through a runner joint (211), the gas-liquid abrasive particle flow joint (208) is provided with three inlets and outlets which are an abrasive particle inflow port end, an abrasive particle outflow port end and an air exhaust port end respectively, the abrasive particle inflow port end, the abrasive particle outflow port end and the air exhaust port end of the gas-liquid abrasive particle flow joint (208) are mutually communicated, the abrasive particle outflow port end of the gas-liquid abrasive particle flow joint (208) is connected with the runner joint (211), the abrasive particle inflow port end of the gas-liquid abrasive particle flow joint (208) is connected with an external liquid metal abrasive particle flow generating device through an abrasive particle inflow port valve (209) and an abrasive particle flow pipeline, the abrasive particle flow produced by the liquid metal abrasive particle flow generating device is a liquid abrasive particle flow, the air exhaust port end of the gas-liquid abrasive particle flow joint (208) is connected with an external air exhaust device through an air exhaust port one-way valve (210), the gas-liquid abrasive particle flow joint (208), the runner joint (211), a hollow runner (202) and the rotary clamping head (201) jointly form a runner part of the rotary runner device, and the abrasive particle flow joint, the runner joint, the hollow runner joint (202) and the rotary clamping head are sequentially lowered in height;

The rotary clamping head (201) comprises a flange-shaped fixed flange end and a main mounting end for fixing a workpiece to be machined, the fixed flange end of the rotary clamping head (201) is fixedly connected with the flange plate (219), a workpiece mounting main groove matched with the machining end of the workpiece to be machined in shape is formed in the main mounting end of the rotary clamping head (201), the machining end of the workpiece to be machined is mounted in the workpiece mounting main groove, a main clamping end O-shaped ring (222) for preventing the machining end of the workpiece to be machined from sliding is arranged in the main workpiece mounting main groove of the rotary clamping head (201), the inner ring of the main clamping end O-shaped ring (222) is attached to the machining end of the workpiece to be machined, and the outer ring of the main clamping end O-shaped ring (222) is attached to the inner wall of the workpiece mounting main groove; the rotary driven plate (304) comprises a cylindrical fixed end and a secondary installation end for fixing a workpiece to be processed, the fixed end of the rotary driven plate (304) is fixed in a circular groove (310) of the supporting block (301), a workpiece installation secondary groove matched with the rear end of the workpiece to be processed is formed in the secondary installation end of the rotary driven plate (304), the rear end of the workpiece to be processed is installed in the workpiece installation secondary groove, a secondary clamping end O-shaped ring for preventing the workpiece to be processed from sliding is arranged at the bottom of the workpiece installation secondary groove of the rotary driven plate (304), an inner ring of the secondary clamping end O-shaped ring is attached to and sleeved at the rear end of the workpiece to be processed, an outer ring of the secondary clamping end O-shaped ring is attached to the inner wall of the workpiece installation secondary groove, a conductive copper ring (223) is arranged on the inner wall of the primary clamping end O-shaped ring, and a conductive copper sheet (307) is arranged on the inner wall of the secondary clamping end O-shaped ring;

The axial lead of the hollow runner (202) and the axial lead of the fixed end of the rotary driven plate (304) are inclined at an angle of 30-60 degrees with the horizontal plane, and the axial lead of the hollow runner (202) and the axial lead of the fixed end of the rotary driven plate (304) are perpendicular to the installation inclined plane of the supporting block (301).

2. The negative pressure polishing device for polishing blind holes of conductive workpieces according to claim 1, wherein: the horizontal linear module (102) is fixed on the horizontal module mounting frame (101) through bolts, the horizontal module mounting frame (101) is fixed on the workbench (5) through bolts, and the vertical linear module (106) is fixed on the horizontal sliding block (103) of the horizontal linear module (102) through bolts.

3. The negative pressure polishing device for polishing blind holes of conductive workpieces according to claim 1, wherein: the gas-liquid abrasive particle flow connector (208) is a square connector, and the gas-liquid abrasive particle flow connector (208) is fixed on the sliding rail connecting plate (205).

4. The negative pressure polishing device for polishing blind holes of conductive workpieces according to claim 1, wherein: the rotary joint fixing seat (206) comprises a runner fixing base and a runner fixing upper seat, arc-shaped grooves matched with the hollow runner (202) are formed in the runner fixing base and the runner fixing upper seat, the runner fixing base and the runner fixing upper seat clamp the hollow runner (202) together, and the runner fixing base and the runner fixing upper seat are fixedly connected through bolts.

5. The negative pressure polishing device for polishing blind holes of conductive workpieces according to claim 1, wherein: the supporting block (301) is a right-angle triangular prism-shaped supporting block (301), two right-angle faces and an installation inclined face are arranged on the supporting block (301), the right-angle faces of the supporting block (301) are fixedly arranged on the workbench (5), and the rotary driven disc (304) is arranged on the installation inclined face of the supporting block through the turntable base.

6. The negative pressure polishing device for polishing blind holes of conductive workpieces according to claim 1, wherein: the middle part of the hollow runner (202) is provided with middle positioning mounting threads for mounting the annular electric slip ring (213), one end of the hollow runner (202) close to the rotary joint (212) is provided with tail positioning mounting threads for connecting the rotary joint (212), and one end of the hollow runner (202) close to the flange (219) is provided with a boss for connecting the flange (219); the two ends of the hollow runner (202) are connected with the flange plate (219) and the rotary joint (212) in a sealing way.

7. A negative pressure polishing method for polishing a blind hole of a conductive workpiece, which adopts the negative pressure polishing device for polishing the blind hole of the conductive workpiece according to claim 1, and is characterized in that: the method specifically comprises the following steps:

Step one: the bottom end of a workpiece to be processed is arranged on a rotary driven disc (304) through an auxiliary clamping end O-shaped ring;

step two: starting a vertical module driving motor (105), and driving a rotary clamping head (201) to move downwards by driving a vertical sliding block (104) on a vertical linear module (106) to move downwards, so that the rotary clamping head (201) is close to a workpiece to be processed on a rotary driven disc (304);

step three: starting a horizontal module driving motor (107), driving a rotary clamping head (201) to move towards a workpiece to be processed in the horizontal direction by driving the horizontal sliding block (103) on the horizontal linear module (102) to horizontally move, and stopping the horizontal module driving motor (107) after the horizontal linear module reaches a proper position;

step four: repeating the second step and the third step, so that the workpiece to be processed and the rotary clamping head (201) are gradually close to each other until the processing end of the workpiece to be processed completely stretches into the rotary clamping head (201), and the main clamping end O-shaped ring (222) in the rotary clamping head (201) is completely sleeved on the processing end of the workpiece to be processed, at the moment, the workpiece to be processed is clamped together by the rotary clamping head (201) and the rotary driven disc (304), and the blind hole of the workpiece to be processed is communicated with the hollow runner (202);

Step five: closing an abrasive grain inflow port valve (209), opening an extraction port one-way valve (210) and starting an air extractor, and connecting the air extractor with the extraction port one-way valve (210) through an air extraction pipeline to extract air, so that the blind hole of a workpiece to be processed and the interior of the hollow runner (202) are in a negative pressure state;

step six: the air extractor is closed after the inside of the blind hole of the workpiece to be processed is in a negative pressure state, and the air extractor is in a negative pressure state all the time because the air extraction port one-way valve (210) only allows air to flow in one direction, so that the inside of the blind hole of the workpiece to be processed is always in the negative pressure state, at the moment, the abrasive grain inflow port valve (209) is opened, and the liquid metal abrasive grain flow generating device is started, so that the liquid metal abrasive grain flow generated in the liquid metal abrasive grain flow generating device sequentially flows through the abrasive grain inflow port valve (209), the air-liquid abrasive grain flow joint (208), the runner joint (211) and the rotary joint (212) to enter the hollow runner (202), and the liquid metal abrasive grain flow can directly flow into the blind hole of the workpiece to be processed because the blind hole of the workpiece to be processed and the hollow runner (202) are in the negative pressure state;

step seven: after the liquid metal abrasive particle flow is injected, an abrasive particle inflow port valve (209) is closed, a rotary driving motor (214) is opened, and the rotary driving motor (214) drives a movable end of a rotary joint (212), a hollow runner (202), a flange plate (219), a rotary clamping head (201) and a whole body formed by a workpiece to be processed to rotate through a synchronous belt mechanism formed by a rotary driving wheel (224), a rotary driven wheel (217) and a rotary synchronous belt (216);

Step eight: a sinusoidal alternating current power supply connected with the three-phase stator coil (302) is turned on, and as the three-phase stator coil (302) generates a rotating magnetic field under an alternating current electric field, the rotating magnetic field generated by the three-phase stator coil (302) during operation drives metal particles in the liquid metal polishing solution to move, so that abrasive particles in the liquid metal polishing solution are accelerated to rotate and impact blind holes of a workpiece to be processed;

step nine: an external square wave alternating current power supply is turned on, square wave alternating current is applied to a workpiece to be processed through a closed loop formed by the annular electric slip ring (213), a slip ring rotor end lead (221), a conductive copper sheet (307), the workpiece to be processed, the conductive copper ring (223) and the flange type electric slip ring (306), an alternating current electric field is formed inside the workpiece to be processed under the action of the square wave alternating current, and metal particles in the liquid metal abrasive particle flow can carry out reciprocating oscillation motion along the axial direction of the blind hole under the action of the alternating current electric field, so that the abrasive particle motion in the liquid metal abrasive particle flow is disordered, and the blind hole polishing of the workpiece to be processed is further accelerated until the blind hole polishing of the workpiece to be processed is completed.

8. The negative pressure polishing method for polishing blind holes of a conductive workpiece according to claim 7, wherein: in the eighth step, the rotation speed and the intensity of a rotating magnetic field generated by the three-phase stator coil (302) are controlled by adjusting the frequency and the voltage of an externally connected sinusoidal alternating current power supply, so that the change of the movement condition of metal particles in the liquid metal polishing solution is realized, and further the change of the polishing efficiency is realized.