Tool electrode and workpiece double-rotation laser electrolysis combined machining device and method

Abstract

The invention relates to a tool electrode and workpiece double-rotation laser electrolysis combined machining device and method, the device comprises a tool electrode rotating mechanism, the tool electrode rotating mechanism is connected to a movement mechanism, the tool electrode rotating mechanism is connected with a laser machining mechanism and an electrolytic machining mechanism, and the tool electrode rotating mechanism is used for achieving laser and electrolytic machining function coupling; annular scanning etching machining of materials is achieved through rotation of a tool electrode around the axis and revolution of a workpiece around the axis of the tool electrode, so that the laser electrolysis combined machining range is widened, and deep hole machining of different hole diameters is achieved. According to the invention, high-quality and high-efficiency processing of multiple-aperture deep small holes in the surfaces of metal and alloy thereof can be realized.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of multi-energy field composite special machining, and particularly relates to a laser-electrolysis composite machining device and method with double rotation of a tool electrode and a workpiece. BACKGROUND

[0002] There are a large number of deep and small hole structures with different hole diameters on core components in the fields of aerospace, national defense equipment, medical equipment, etc., and most of these core components are made of difficult-to-machine metal materials. For such difficult-to-machine materials, traditional machining methods have been unable to meet the increasing machining requirements of high surface quality and integrity. Composite energy field special machining method is an effective means to realize high-quality and efficient machining at present. Laser-electrolysis composite machining has the dual advantages of high efficiency of laser machining and high quality of electrochemical machining. In the machining process, laser and electrochemical energy are conducted along the axis of a specially designed tool electrode, promote each other and act on the material machining area together, so that the material can be removed efficiently and with high quality.

[0003] However, in the current laser-electrolysis composite machining (Sun C, Wang Y, Yang Y, et al. Study on the Effect of Electrolytes on Processing Efficiency and Accuracy of Titanium Alloy Utilizing Laser and Shaped Tube Electrochemical Machining [J]. Materials, 2024, 17(3).) for deep and small hole structures, the tool electrode structure is complex and not easy to replace the actual application tool electrode; the size of the tool electrode is very limited, and the range of processable hole diameters is small. When there are multiple deep and small hole structures with different hole diameters on the part, the machining requirements cannot be met. SUMMARY

[0004] In order to overcome the above-mentioned technical defects, the purpose of the present application is to provide a laser-electrolysis composite machining device and method with double rotation of a tool electrode and a workpiece. The annular scanning and etching machining of the material is realized by the rotation of the tool electrode around the axis and the revolution of the workpiece around the axis of the tool electrode, so as to increase the range of laser-electrolysis composite machining and realize the machining of deep holes with different diameters.

[0005] In order to achieve the above-mentioned purpose, the technical scheme is as follows: A laser-electrolysis composite machining device with double rotation of a tool electrode and a workpiece, comprising a tool electrode rotating mechanism, the tool electrode rotating mechanism being connected to a movement mechanism, the tool electrode rotating mechanism being connected to a laser machining mechanism and an electrolytic machining mechanism, and the tool electrode rotating mechanism being used to realize the coupling of laser and electrolytic machining functions.

[0006] The tool electrode rotating mechanism comprises a rotating shaft 9 fixed in the outer shell 8 by an upper bearing 6 and a lower bearing 18, the upper bearing 6 is positioned above an upper cover plate 5, the lower bearing 18 is positioned below a lower cover plate 11, the upper cover plate 5 and the lower cover plate 11 are connected to the outer shell 8; the rotating shaft 9 is provided with an electrolyte flow channel in communication with an electrolyte interface 21 of the outer shell 8, and the electrolyte flow channel is sealed with the outer shell 8 by a sealing ring; The upper part of the rotating shaft 9 is connected to the upper water stop plug fixing screw 4 and sealed, the upper water stop plug fixing screw 4 is connected to the processed optical fiber 1; the lower part of the rotating shaft 9 is connected to the lower water stop plug fixing screw 15 and sealed, the lower water stop plug fixing screw 15 is connected to the tool electrode 13, the bottom of the processed optical fiber 1 extends into the tool electrode 13 and is flush with the bottom of the tool electrode 13 to transmit the laser to the processing position; the top of the rotating shaft 9 is connected to the rotating shaft of the hollow shaft stepping motor 2; the bottom of the rotating shaft 9 is in contact with the conductive carbon brush 16 with a support, and the conductive carbon brush 16 with a support is provided with a conductive screw 17.

[0007] The motion mechanism comprises an X-axis 29, a Y-axis 30 and a Z-axis 26, the Y-axis 30 is connected to the X-axis 29, the Y-axis 30 is connected to a workpiece clamp 36, the workpiece clamp 36 is connected to a workpiece 27, and the X-axis 29 and the Y-axis 30 are responsible for the circular circumferential interpolation motion of the workpiece 27; the Z-axis 26 is connected to the tool electrode rotating mechanism, and the Z-axis 26 is responsible for the feeding motion of the tool electrode rotating mechanism.

[0008] The laser processing mechanism comprises a laser 25, the laser 25 is connected through a transmission optical fiber 39 and a multimode fiber coupler 38, the multimode fiber coupler 3 is connected to the processed optical fiber 1, and the multimode fiber coupler 38 realizes the coupling of the transmission optical fiber 39 and the processed optical fiber 1.

[0009] The electrolytic processing mechanism comprises a direct current power supply 37 and an electrolyte liquid system, the negative electrode of the direct current power supply 37 is connected to the conductive screw 17 above the conductive carbon brush 16 with a support of the tool electrode rotating mechanism, the negative electrode circuit is communicated to the tool electrode 13 by the contact between the conductive carbon brush 16 with a support and the rotating shaft 9; the positive electrode of the direct current power supply 37 is connected to the workpiece clamp 36 to realize the conduction of the positive electrode circuit; the electrolyte liquid system comprises an electrolyte storage tank 31, the electrolyte in the electrolyte storage tank 31 is pumped into the liquid path by a plunger pump 33, part of it flows back to the electrolyte storage tank 31 through a pressure regulating valve 34, and the other part reaches the electrolyte interface 21 of the tool electrode rotating mechanism through a pressure gauge 35, and then reaches the workpiece 27 processing position through the tool electrode 13 after the internal flow channel of the rotating shaft 9, and the backflow electrolyte collected by the electrolyte collecting tank 28 flows back to the electrolyte storage tank 31 through the filter 32.

[0010] The processing optical fiber 1 is composed of an outer wall protection layer 102 and an internal main body quartz optical fiber 101, and the main body quartz optical fiber 101 is partially located inside the tool electrode 13.

[0011] The tool electrode 13 is a double-layer structure, and the main body material is a hollow capillary stainless steel pipe 131, and the outer wall of the hollow capillary stainless steel pipe 131 has an insulating layer 132.

[0012] The processing method of the laser electrolysis combined processing device with the tool electrode and the workpiece rotating together comprises the following steps: 1) The laser is transmitted to the processing area through the transmission optical fiber 39, the multimode optical fiber coupler 38 and the processing optical fiber 1; 2) The electrolyte is transmitted to the tool electrode 13 through the electrolyte interface 21 and is transmitted to the processing area through the tool electrode 13; 3) The rotation shaft 9 is driven to rotate by the hollow shaft stepping motor 2, so that the rotation movement of the tool electrode 13 is realized; 4) The workpiece 27 is driven to make a circular circumferential difference compensation movement by the X shaft 29 and the Y shaft 30, and the workpiece 27 is fed downward along the Z shaft 26 to realize the processing of different size hole structures on the surface of the workpiece 27.

[0013] Compared with the prior art, the beneficial effects of the present application are: The present application transmits the laser through the transmission optical fiber 39, and when reaching the tool electrode rotating mechanism, the laser is transmitted to the processing optical fiber 1 through the multimode optical fiber coupler 38, so that the relative rotation function of the processing optical fiber 1 and the stable transmission of the laser are realized; the hollow shaft stepping motor 2 is coaxially connected with the rotation shaft 9, so that the rotation speed of the tool electrode 13 is conveniently adjusted, the transverse size of the tool electrode rotating mechanism is reduced, and the ability of processing parts with narrow structures is increased; the workpiece 27 is in a circular revolution mode and the tool electrode 13 is in a self-transmission mode, so that the processing hole diameter range is increased; and the present application can realize high-quality and high-efficiency processing of various hole diameters on the surface of metal and its alloy. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 It is a schematic diagram of the overall device of the embodiment of the present application.

[0015] Figure 2 It is a schematic diagram of the tool electrode rotating part of the embodiment of the present application.

[0016] Figure 3 It is a schematic diagram of the internal structure of the tool electrode rotating part of the embodiment of the present application.

[0017] Figure 4 It is a schematic diagram of the processing optical fiber of the embodiment of the present application.

[0018] Figure 5 It is a schematic diagram of the tool electrode of the embodiment of the present application.

[0019] Figure 6 Figure 1 is a schematic diagram of the electrolyte flow channel of the tool electrode rotating part of the embodiment of the present application.

[0020] Figure 7(a) is a schematic diagram of the tool electrode single rotation machining of the embodiment of the present application; Figure 7(b) is a schematic diagram of the tool electrode and workpiece double rotation machining result of the embodiment of the present application.

[0021] Figure 8(a) is a tool electrode single rotation machining result diagram of the embodiment of the present application; Figure 8(b) is a tool electrode and workpiece double rotation machining result diagram of the embodiment of the present application. DETAILED DESCRIPTION

[0022] The present application will be described in detail below with reference to the embodiments and the accompanying drawings.

[0023] As shown in Figure 1 , Figure 2 , Figure 3 , a tool electrode and workpiece double rotation laser electrolytic composite machining device, comprising a tool electrode rotating mechanism, the tool electrode rotating mechanism being connected to a movement mechanism, the tool electrode rotating mechanism being connected to a laser machining mechanism and an electrolytic machining mechanism, the tool electrode rotating mechanism being used to realize coupling of the laser and electrolytic machining functions into the tool electrode 13 and rotation of the tool electrode 13.

[0024] As shown in Figure 2 , 3, the tool electrode rotating mechanism comprises a rotating shaft 9, the rotating shaft 9 being fixed in an external housing 8 by an upper bearing 6 and a lower bearing 18, an upper cover plate 5 being positioned above the upper bearing 6, a lower cover plate 11 being positioned below the lower bearing 18, the upper cover plate 5 and the lower cover plate 11 being connected to the external housing 8 by cover plate fixing screws 12; the rotating shaft 9 is provided with an electrolyte flow channel in communication with an electrolyte interface 21 of the external housing 8, the electrolyte flow channel being provided with a lower sealing ring 19, a middle lower sealing ring 20, a middle upper sealing ring 22, an upper sealing ring 23 and the external housing 8 for sealing; The upper part of the rotating shaft 9 is connected to an upper water stop plug fixing screw 4 and realizes sealing by means of an upper water stop plug 7, the upper water stop plug fixing screw 4 being connected to a machining optical fiber 1 through an optical fiber fixing top screw 3; the lower part of the rotating shaft 9 is connected to a lower water stop plug fixing screw 15 and realizes sealing by means of a lower water stop plug 10, the lower water stop plug fixing screw 15 being connected to a tool electrode 13 through a tool electrode fixing top screw 14, the machining optical fiber 1 being inserted into the tool electrode 13 and being flush with the bottom of the tool electrode 13 to transmit the laser to the machining position; the top of the rotating shaft 9 is connected to a hollow shaft stepping motor 2 rotating shaft to realize rotation of the tool electrode 13; the bottom of the rotating shaft 9 is in contact with a bracketed conductive carbon brush 16, the bracketed conductive carbon brush 16 being provided with a conductive screw 17 for connecting the negative pole of a power supply.

[0025] The tool electrode rotating mechanism is connected through the housing fixing screw hole 24 on the external housing 8 and the motion mechanism.

[0026] The motion mechanism includes an X-axis 29, a Y-axis 30 connected to the X-axis 29, and a Z-axis 26 connected to the tool electrode rotating mechanism, the Y-axis 30 being connected to a workpiece clamp 36 connected to a workpiece 27, the X-axis 29 and the Y-axis 30 being responsible for the circular circumferential interpolation motion of the workpiece 27, and the Z-axis 26 being responsible for the feed motion of the tool electrode rotating mechanism.

[0027] The laser processing mechanism includes a laser 25 for providing green nanosecond laser, the laser 25 being connected through a transmission optical fiber 39 and a multimode fiber coupler 38, the multimode fiber coupler 38 being connected to a processing optical fiber 1; after the laser is emitted from the laser 25, it is transmitted by the transmission optical fiber 39 to the position of the multimode fiber coupler 38, the multimode fiber coupler 38 achieving coupling of the transmission optical fiber 39 and the processing optical fiber 1, so as to transmit the laser to the processing position.

[0028] The electrolytic processing mechanism includes a direct current power supply 37 and an electrolyte liquid path system, the negative electrode of the direct current power supply 37 being connected to the conductive screw 17 on the upper surface of the bracketed conductive carbon brush 16 of the tool electrode rotating mechanism, the negative electrode circuit being communicated to the tool electrode 13 by the bracketed conductive carbon brush 16 contacting the rotating shaft 9; the positive electrode of the direct current power supply 37 being connected to the workpiece clamp 36 to realize conduction of the positive electrode circuit; the electrolyte liquid path system includes an electrolyte storage tank 31, the electrolyte in the electrolyte storage tank 31 being pumped into the liquid path by a plunger pump 33, part of the electrolyte flowing back to the electrolyte storage tank 31 through a pressure regulating valve 34, and the other part of the electrolyte reaching the electrolyte interface 21 of the tool electrode rotating mechanism through a pressure gauge 35, then flowing through the internal flow channel of the rotating shaft 9 and the tool electrode 13 to reach the processing position of the workpiece 27, and the backflowing electrolyte collected by the electrolyte collection tank 28 outside the workpiece clamp 36 flowing back to the electrolyte storage tank 31 through a filter 32.

[0029] As shown in Figure 4 The processing optical fiber 1 is composed of an outer wall protection layer 102 and an internal main body quartz optical fiber 101, and the main body quartz optical fiber 101 is partially located inside the tool electrode 13. Figure 5 The tool electrode 13 has a double-layer structure, the main body material being a hollow capillary stainless steel tube 131, and the outer wall of the hollow capillary stainless steel tube 131 having an insulating layer 132. Figure 6 After the electrolyte flows into the electrolyte interface 21, it enters the inside through the porous structure on the rotating shaft 9, and then is transmitted to the processing area through the gap between the main body quartz optical fiber 101 and the hollow capillary stainless steel tube 131.

[0030] The laser emitted by the laser 25 is transmitted by the transmission optical fiber 39, coupled into the processing optical fiber 1 through the multimode fiber coupler 38, transmitted to the processing area for processing; the electrolyte flows into the tool electrode 13 through the flow channel on the rotating shaft 9 of the tool electrode rotating mechanism, and is transmitted to the processing area through the tool electrode 13; before the processing starts, the rotating speed of the hollow shaft stepping motor 2 is adjusted, and the rotating radius and speed of the workpiece 27 are determined, so that the workpiece 27 is connected to the positive electrode of the direct current power supply 37 through the workpiece clamp 36 and the positive electrode of the direct current power supply 37, and the tool electrode 13 is connected to the negative electrode of the direct current power supply 37 through the carbon brush 16 with a support and the conductive screw 17; the laser is transmitted to the processing area after passing through the processing optical fiber 1, and the electrolyte surrounds the outside of the processing optical fiber 101 and synchronously reaches the processing surface of the workpiece 27 through the inside of the tool electrode 13; after the direct current power supply 37 is turned on, an electric field is formed between the workpiece 27 and the tool electrode 13; with the feeding of the Z-axis 26, the surface material of the workpiece processing area is removed under the action of the laser and the electrolyte; the processing product flows back to the electrolyte storage tank 31 with the electrolyte, as shown in the schematic diagrams of the workpiece without rotation and the workpiece with rotation processing in Figures 7(a) and 7(b), it can be seen that the workpiece 27 has a larger processing aperture range after rotation.

[0031] The processing method of the laser-electrolytic combined processing device with double rotation of a tool electrode and a workpiece comprises the following steps: 1) The main body quartz optical fiber 101 inside the processing optical fiber 1 is connected to the inside of the tool electrode 13, and the outer wall protection layer 102 is partially connected to the multimode fiber coupler 38; the electrolyte liquid path system is connected, and the tool electrode 13 is connected to the lower water stop plug fixing screw 15; the position of the tool electrode 13 is adjusted to ensure that the end face of the main body quartz optical fiber 101 is flush with the end face of the tool electrode 13, and the tool electrode fixed top screw 14 is locked; 2) The conductive screw 17 is connected to the negative electrode of the direct current power supply 37, the workpiece clamp 36 is connected to the positive electrode of the direct current power supply 37, the workpiece 27 is fixed on the workpiece clamp 36 and locked; 3) After the laser emitted by the laser processing mechanism laser 25 is transmitted through the transmission optical fiber 39, the end face of the transmission optical fiber 39 and the end face of the processing optical fiber 1 are coaxially and accurately butt-jointed through the adjustment of the multimode fiber coupler 38; 4) The gap between the tool electrode 30 and the workpiece 27 is adjusted, the tool electrode 13 and the workpiece 27 are rotated, the Z-axis 26 starts to move, the workpiece 27 is driven to do a circular circumferential difference compensation motion by the X-axis 29 and the Y-axis 30, different size hole structure processing is realized on the surface of the workpiece 27 with the downward feeding of the Z-axis 26, until the workpiece 27 is completely processed and penetrated by the tool electrode 13; 5) Turn off the laser, turn off the direct current power supply, turn off the electrolyte liquid path system, stop the rotation of the tool electrode 13 and the workpiece 27, and the processing is completed.

[0032] The diameter of the processing optical fiber 1 is 0.1-0.6 mm.

[0033] The laser power of the laser 25 is 0-50 W.

[0034] The rotating speed of the tool electrode 13 is 0-200 r / min.

[0035] The annular rotating speed of the workpiece 27 is 0-100 mm / s.

[0036] The annular rotating radius of the workpiece 27 is 0-0.6 mm.

[0037] The inner diameter of the hollow metal tube used by the tool electrode 13 is 0.4-0.7 mm, and the outer diameter is 0.9-1.2 mm.

[0038] The pressure of the electrolyte liquid path system is 0.4-5 Mpa.

[0039] The electrolyte composition is selected from one or a mixture of sodium nitrate, sodium chloride, and sodium hypochlorite.

[0040] The electrolyte liquid path system pressure is independently selected from any value or any range between two points in 0.4 Mpa, 0.8 Mpa, 1.2 Mpa, 1.6 Mpa, 2 Mpa, 3 Mpa, 4 Mpa, and 5 Mpa; and the electrolyte concentration is selected from 10-20% wt.

[0041] The initial machining gap between the bottom end of the tool electrode 13 and the workpiece 27 is 0.05-0.3 mm; and the voltage between the tool electrode 13 and the workpiece 27 is 15-60 V.

[0042] The beneficial effects of the embodiment are: As shown in FIG. 8(a), the hole diameter processed only by the tool electrode 13 is about 1.30 mm; and as shown in FIG. 8(b), the hole diameter processed by the tool electrode 13 and the workpiece 27 is about 1.65 mm. The double-rotation processing of the tool electrode 13 and the workpiece 27 significantly improves the processing hole diameter range, and can realize one-time uninterrupted processing of various hole diameters, providing a new method for processing parts with various hole diameter structures.

Claims

1. A laser-electrolytic composite machining device with dual rotation of tool electrode and workpiece, characterized in that: It includes a tool electrode rotating mechanism, which is connected to the motion mechanism and is connected to the laser processing mechanism and the electrolytic processing mechanism. The tool electrode rotating mechanism is used to couple the laser and electrolytic processing functions.

2. The laser-electrolytic composite processing apparatus according to claim 1, characterized in that: The motion mechanism includes an X-axis (29), a Y-axis (30), and a Z-axis (26). The Y-axis (30) is connected to the X-axis (29), and the Y-axis (30) is connected to the workpiece fixture (36). The workpiece fixture (36) is connected to the workpiece (27). The X-axis (29) and Y-axis (30) are responsible for the annular circumferential interpolation motion of the workpiece (27). The Z-axis (26) is connected to the tool electrode rotation mechanism and is responsible for the feed motion of the tool electrode rotation mechanism.

3. The laser-electrolytic composite processing apparatus according to claim 1, characterized in that: The tool electrode rotating mechanism includes a rotating shaft (9), which is fixed in the outer housing (8) by an upper bearing (6) and a lower bearing (18). An upper cover plate (5) is positioned above the upper bearing (6), and a lower cover plate (11) is positioned below the lower bearing (18). The upper cover plate (5) and the lower cover plate (11) are connected to the outer housing (8). The rotating shaft (9) is provided with an electrolyte flow channel that communicates with the electrolyte interface (21) of the outer housing (8). The electrolyte flow channel is provided with a sealing ring and is sealed to the outer housing (8). The upper part of the rotating shaft (9) is connected to the upper water stop plug fixing screw (4) and sealed. The upper water stop plug fixing screw (4) is connected to the processing optical fiber (1). The lower part of the rotating shaft (9) is connected to the lower water stop plug fixing screw (15) and sealed. The lower water stop plug fixing screw (15) is connected to the tool electrode (13). The bottom of the processing optical fiber (1) extends into the tool electrode (13) and is flush with the bottom of the tool electrode (13) to transmit the laser to the processing position. The top of the rotating shaft (9) is connected to the shaft of the hollow shaft stepper motor (2). The bottom of the rotating shaft (9) is in contact with the conductive carbon brush (16) with bracket. The conductive carbon brush (16) with bracket is provided with a conductive screw (17).

4. The laser-electrolytic composite processing apparatus according to claim 3, characterized in that: The laser processing mechanism has a laser (25), which is connected to a transmission fiber (39) and a multimode fiber coupler (38). The multimode fiber coupler (38) is connected to a processing fiber (1), and the multimode fiber coupler (38) enables the coupling of the transmission fiber (39) and the processing fiber (1).

5. The laser-electrolytic composite processing apparatus according to claim 3, characterized in that: The electrolytic processing mechanism includes a DC power supply (37) and an electrolyte circuit system. The negative terminal of the DC power supply (37) is connected to the conductive screw (17) on the conductive carbon brush (16) with a support on the tool electrode rotating mechanism. The negative circuit is connected to the tool electrode (13) by the contact between the conductive carbon brush (16) with the support and the rotating shaft (9). The positive terminal of the DC power supply (37) is connected to the workpiece fixture (36) to realize the conduction of the positive circuit. The electrolyte circuit system includes an electrolyte storage tank (31). The electrolyte in the electrolyte storage tank (31) is drawn into the liquid circuit by the plunger pump (33). Part of it flows back to the electrolyte storage tank (31) through the pressure regulating valve (34), and the other part reaches the electrolyte interface (21) of the tool electrode rotating mechanism through the pressure gauge (35). After passing through the internal flow channel of the rotating shaft (9), it reaches the workpiece (27) processing position through the tool electrode (13). The returned electrolyte collected by the electrolyte collection tank (28) flows back to the electrolyte storage tank (31) through the filter (32).

6. The laser-electrolytic composite processing apparatus according to claim 3, characterized in that: The processing optical fiber (1) consists of an outer protective layer (102) and an inner main quartz optical fiber (101), with the main quartz optical fiber (101) located inside the tool electrode (13).

7. The laser-electrolytic composite processing apparatus according to claim 3, characterized in that: The tool electrode (13) has a double-layer structure. The main material is a hollow capillary stainless steel tube (131), and the outer wall of the hollow capillary stainless steel tube (131) has an insulating layer (132).

8. A processing method using the laser-electrolytic composite processing apparatus according to any one of claims 1-7, characterized in that, Includes the following steps: 1) The laser is transmitted to the processing area via the transmission fiber (39), the multimode fiber coupler (38), and the processing fiber (1); 2) The electrolyte is transferred to the tool electrode (13) through the electrolyte interface (21), and then to the processing area through the tool electrode (13); 3) The tool electrode (13) is rotated by driving the rotating shaft (9) through the hollow shaft stepper motor (2); 4) The workpiece (27) is driven by the X-axis (29) and Y-axis (30) to make a circular circumferential differential motion. As the Z-axis (26) feeds downward, different sizes of hole structures are processed on the surface of the workpiece (27).

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