CN103302367B - A kind of external spiral structure sinker electric discharge machining method - Google Patents
A kind of external spiral structure sinker electric discharge machining method Download PDFInfo
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- CN103302367B CN103302367B CN201310087097.XA CN201310087097A CN103302367B CN 103302367 B CN103302367 B CN 103302367B CN 201310087097 A CN201310087097 A CN 201310087097A CN 103302367 B CN103302367 B CN 103302367B
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Abstract
The invention discloses a kind of external spiral structure sinker electric discharge machining method, it is characterised in that comprise the steps: step 1: adopt easy machined electrode materials processing tool-electrode according to the outline parameter of external spiral structure; Step 2: process board-like material threaded hole electrode on board-like material with tool-electrode; Step 3: adopt Electric Discharge Machining mode according to board-like material threaded hole electrode machining external spiral structure. The present invention first adopts conventional easily machined electrode materials processing to go out tool-electrode, threaded hole is processed further according to tool-electrode, edm forming technology is finally adopted to process the external spiral structure of high hard material according to threaded hole, the external spiral structure precision processed by this invention is high, cutter is less demanding, and processing cost is relatively low.
Description
Technical field
The invention belongs to machining process, be specifically related to the sinker electric discharge machining method of a kind of external spiral structure, can be used for small size, great-lift angle, hard external spiral structure multi-thread, high-precision, high.
Background technology
At present, multi-thread helical structure conventional machining has following a few class processing method: turning, milling, broaching. For the external spiral structure of small size, great-lift angle, adopting method for turning, its shaped profile turning cutter rigidity is more weak. Adopt milling method, then tool radius is less, and processing high hard material abrasion is bigger. Adopting special spiral broaching machine can process external spiral structure, but can not carry out high accuracy size screw processing for high hardness material, and difficulty purchased by spiral broach, single-piece manufacturing cost is very high.
Summary of the invention
It is an object of the invention to for prior art defect, it is provided that the external spiral structure sinker electric discharge machining method that a kind of high hardness material, machining accuracy are high.
The present invention is achieved in that a kind of external spiral structure sinker electric discharge machining method, comprises the steps:
Step 1: adopt easy machined electrode materials processing tool-electrode according to the outline parameter of external spiral structure;
Step 2: process board-like material threaded hole electrode on board-like material with tool-electrode;
Step 3: adopt Electric Discharge Machining mode according to board-like material threaded hole electrode machining external spiral structure.
Described easy machined electrode material is copper, alloyed copper, tungsten copper or graphite, and described board-like material is copper, alloyed copper, tungsten copper or graphite.
Process gap according to external spiral structure and threaded hole is processed gap and calculated the processing dimension of the tool-electrode that need to process.
Described tool-electrode includes the tool-electrode of two kinds of precision according to external spiral structure machining accuracy, and thick tool-electrode is that external spiral physical dimension amplifies 0.4��0.5mm; Essence tool-electrode is that external spiral physical dimension amplifies 0.1��0.2mm.
Described tool-electrode includes the tool-electrode of three kinds of precision according to external spiral structure machining accuracy, and thick tool-electrode is that external spiral physical dimension amplifies 0.4��0.5mm; Half essence tool-electrode is that external spiral physical dimension amplifies 0.2��0.3mm; Essence tool-electrode is that external spiral physical dimension amplifies 0.1��0.2mm.
The processing method of described tool-electrode is numerical control milling method.
The method of described machining plate-like material threaded hole electrode is that copper beats copper, alloyed copper beats alloyed copper, tungsten copper broken by tungsten copper or graphite beats graphite sinker electric discharge machining method. The material that actually board-like material is identical with the easy machined electrode material selection of machining tool electrode, namely tool-electrode is copper, then board-like material is also copper, tool-electrode is alloyed copper, board-like material is also alloyed copper, and tool-electrode is tungsten copper, and board-like material is also tungsten copper, tool-electrode is graphite, and board-like material is also graphite.
The method of machining plate-like material threaded hole electrode is:
(1) technique of alignment in Electric Discharge Machining is adopted to carry out being directed at and fixing the board-like material after preprocessing;
(2) with 3R fixture, tool-electrode is fixed on electric spark former spindle, adopts the technique of alignment in Electric Discharge Machining to carry out being directed at and demarcating;
(3) it is processed obtaining corresponding threaded hole to board-like material with tool-electrode. Threaded hole is corresponding with tool-electrode.
The method of machining plate-like material threaded hole electrode is:
(1) technique of alignment in Electric Discharge Machining is adopted to carry out being directed at and fixing the board-like material after preprocessing;
(2) with 3R fixture, different accuracy tool-electrode is fixed on electric spark former spindle, adopts the technique of alignment in Electric Discharge Machining to carry out being directed at and demarcating;
(3) it is processed obtaining corresponding different accuracy threaded hole to board-like material with different accuracy tool-electrode.
The method of described board-like material threaded hole electrode is:
(1) the external spiral structure crude green body after preprocessing is placed on electric spark former spindle, adopts the technique of alignment in Electric Discharge Machining to carry out being directed at and demarcating;
(2) utilization is counter copies mould processing method, utilizes board-like material threaded hole electrode to adopt edm forming technology processing external spiral structure.
The described method according to the threaded hole processing external spiral structure on board-like material is:
(1) the external spiral structure crude green body after preprocessing is placed on electric spark former spindle, adopts the technique of alignment in Electric Discharge Machining to carry out being directed at and demarcating;
(2) utilization is counter copies mould processing method, utilizes the threaded hole of different accuracy on board-like material threaded hole electrode to adopt edm forming technology processing external spiral structure successively. The precision of external spiral structure meets the requirements.
The 3R fixture used when the 3R fixture of described machining tool electrode and processing threaded hole is same fixture.
Beneficial effects of the present invention:
The present invention first adopts conventional easily machined electrode materials processing to go out tool-electrode, board-like material threaded hole electrode is processed further according to tool-electrode, edm forming technology is finally adopted to go out the external spiral structure of high hard material according to board-like material threaded hole electrode machining, the external spiral structure precision processed by this invention is high, cutter is less demanding, and processing cost is relatively low.
The tool-electrode adopting two or three precision is processed, it is possible to be greatly improved working (machining) efficiency under the premise ensureing machining accuracy. The threaded hole of electrode machining rough grade out is had first with unskilled workman, shape rapidly external spiral structure, then recycling essence tool-electrode or half essence tool-electrode and Seiko have electrode machining threaded hole out, dumming external spiral structure is carried out further polish, obtaining high-precision external spiral structure, working (machining) efficiency is also higher simultaneously.
The internal coiling electrode that the tool-electrode of the present invention can match with external spiral structure adopts same mathematical model, therefore external spiral structure is higher with internal coiling quality of fit, can be controlled in 0.01��0.015mm.
Tool-electrode manufacture and the use of the present invention adopt same 3R fixture, thus ensureing that electrode manufactures benchmark and has same datum with electrode discharge processing, reducing tool-electrode and changing, in manufacture and use procedure, the positioning datum error caused;
The threaded hole manufacture of the present invention is to complete on electric spark shaping mill, and due to nothing Set and Positioning again after having manufactured, just directly externally helical structure part carries out electro-discharge machining, decreases the positioning datum error that processing conversion causes.
Accompanying drawing explanation
Fig. 1 is the structural representation of embodiment of the present invention China and foreign countries helical structure;
Fig. 2 is the schematic diagram of tool-electrode in the embodiment of the present invention;
Fig. 3 is the schematic diagram of the board-like material threaded hole electrode in the embodiment of the present invention;
Fig. 4 is the schematic flow sheet of the external spiral structure sinker electric discharge machining method in the embodiment of the present invention.
Instantiation mode
Below in conjunction with drawings and Examples, the method for the present invention is described in detail.
Embodiment
The HYPERSPARK2HS type that electric spark shaping mill is the production of Archie Xia meter Er company of Switzerland that test is used.
The present embodiment to prepare external spiral structure for high strength elastic Steel material, �� 10 �� 0.03 path, �� 12 �� 0.03 central diameter, the big footpath of �� 15 �� 0.03,87 �� of lead angles, nine line external spiral structures. Its product structure characteristic is that external cylindrical surface has nine rectangle external spirals, and spiral is evenly distributed, and shape is similar to nine head threads, spiral normal section tooth wide for wide be 2.5 �� 0.01mm rectangle. See Fig. 1.
As shown in Figure 4, the processing method of this external spiral structure, comprise the steps:
Step 1: adopt pure copper material machining tool electrode according to the outline parameter of above-mentioned nine line external spirals, the rapidoprint of tool-electrode can adopt the easy machined electrode material of routine, such as fine copper, alloyed copper, tungsten copper or graphite etc., the present embodiment uses fine copper, but protection scope of the present invention is not limited to fine copper;
The present invention adopts external thread structure part processing gap and " copper beats copper " to process gap and designs thick tool-electrode, half essence tool-electrode and essence tool-electrode, take numerical control mill method to process above-mentioned three kinds of precision tools electrodes, the present embodiment adopts the tool-electrode of three kinds of precision, it is for the balance of the working (machining) efficiency and machining accuracy obtaining optimum, but the tool-electrode of two kinds of precision is equally possible realizes the purpose of the present invention, therefore the precision kind of tool-electrode is not by the restriction of the present embodiment.
The specific process of this step is as follows:
(1) tool-electrode design:
Tool-electrode designs, and sees Fig. 2.
Principle: according to the anti-electrode outline of copying of external thread structure, and consider external spiral electric machining gap value, " copper beats copper " electric machining gap value.
Precision: determine roughing, semifinishing, finisher electrode outer profile size respectively according to Electric Discharge Machining parameter. Press tool-electrode material selection T2, workpiece material for 3J33, determine for counter, roughing electrode size copies that product size amplifies 0.4��0.5mm accordingly, for counter, semifinishing electrode size copies that product size amplifies 0.20��0.30mm accordingly, polish electrode size amplifies 0.10��0.20mm accordingly for anti-product size of copying respectively according to Electric Discharge Machining parameter.
(2) manufacture of tool-electrode
Tool-electrode manufactures, and sees Fig. 4 (a)
Key point: the high dimensional accuracy of product requires that the determining electrode accuracy of manufacture is higher, now electrode accuracy of manufacture grade is already close to Machine Manufacture accuracy class, take the loss of significance that the method reduction lathe of error correction, frock, cutter cause, ensureing that electrode precision form and position tolerance is 5 ��m respectively, shape and size precision is 8 ��m.
Step 2: process board-like material threaded hole electrode on board-like material with tool-electrode;
The electric discharge machining process preparing board-like material threaded hole electrode uses and manufactures same 3R fixture with tool-electrode, reduce tool-electrode and manufacturing and the positioning datum error caused is changed in use procedure.
The specific process of this step is as follows:
(1) consider part working (machining) efficiency, design board-like material threaded hole electrode, see Fig. 3
(2) in order to ensure that board-like material threaded hole electrode has higher reference precision when processing external spiral, require that board-like material threaded hole electrode has higher alignment fiducials: upper and lower two parallel to the large face degree 0.01, it is set as two right-angle sides and two big face perpendicularity 0.02, the mutual perpendicularity 0.02 of X, Y benchmark.
(3) �� 9.8 hole is processed at board-like material threaded hole place in advance
(4) copper plate electrode after preprocessing is placed on edm forming machine worktable, and adopts the technique of alignment in Electric Discharge Machining to carry out being directed at and fixing;
(5) 3R fixture is utilized to be fixed on electric spark former spindle the thick tool-electrode of NC Milling, half essence tool-electrode, essence tool-electrode, and adopt the technique of alignment in Electric Discharge Machining to carry out being directed at and demarcating, as shown in Fig. 4 (b);
(6) be utilized respectively thick tool-electrode, partly essence tool-electrode, essence tool-electrode adopts " copper beats copper " Electric Discharge Machining mode to process the board-like material threaded hole electrode placed on the table. Tool-electrode processing electrical quantity is: 21 �� s��18 �� s between electric current 2.4A��3.2A, pulsewidth 27 �� s��24 �� s, arteries and veins; The material that board-like material uses is except fine copper, it is also possible to according to the material selection alloyed copper of tool-electrode, tungsten copper or graphite, alloyed copper beats alloyed copper, tungsten copper broken by tungsten copper or graphite is beaten graphite sinker electric discharge machining method and is processed in employing.
Step 3: adopt Electric Discharge Machining mode according to board-like material threaded hole electrode machining external spiral structure.
The present invention adopts the board-like material threaded hole electrode after tool-electrode processing as external spiral machined electrode, without Set and Positioning again after manufacturing due to board-like material threaded hole electrode, just directly externally helical structure part carries out generating processing, therefore decreases board-like material threaded hole electrode and manufacturing and changing, in use procedure, the positioning datum error caused.
The specific process of this step is as follows:
(1) preprocessing external spiral structure crude green body is cylindrical is �� 15.2;
(2) the external spiral structure crude green body after preprocessing is placed on electric spark former spindle, and adopting the technique of alignment in Electric Discharge Machining that the copper coin forehand electrode that the external spiral constitutional detail alignment on main shaft machines is gone forward side by side rower calmly, processing mode is shown in Fig. 4 (c);
(3) utilization is counter copies mould processing method, and the processing mode external helical structure crude green body successively being respectively adopted " copper breaks steel " carries out roughing, semifinishing and polish. The rough machining electrical parameters of external spiral constitutional detail: 60 �� s��56 �� s between electric current 13A��21A, pulsewidth 178 �� s��154 �� s, arteries and veins;Semifinishing electrical quantity: 42 �� s��37 �� s between electric current 8A��6.2A, pulsewidth 100 �� s��75 �� s, arteries and veins; Fine machining electrical parameters: 27 �� s��21 �� s between electric current 4.4 �� s��3.2A, pulsewidth 37 �� s��27 �� s, arteries and veins.
The present invention propose a kind of for small size, great-lift angle, hard external spiral structure multi-thread, high-precision, high sinker electric discharge machining method, the method can be effectively ensured high accuracy external spiral infrastructure product batch machining. This intellectual achievement applies to solve a very big difficult problem in actual production, has very strong application prospect.
Claims (10)
1. an external spiral structure sinker electric discharge machining method, it is characterised in that comprise the steps:
Step 1: adopt easy machined electrode materials processing tool-electrode according to the outline parameter of external spiral structure;
Step 2: be placed on edm forming machine worktable by the board-like material after preprocessing, processes board-like material threaded hole electrode with tool-electrode on board-like material, without Set and Positioning again after the manufacture of board-like material threaded hole electrode; The 3R fixture used when the 3R fixture of machining tool electrode and processing threaded hole is same fixture;
Step 3: adopt Electric Discharge Machining mode according to board-like material threaded hole electrode machining external spiral structure.
2. external spiral structure sinker electric discharge machining method according to claim 1, it is characterised in that described easy machined electrode material is copper, alloyed copper or graphite, and described board-like material is copper, alloyed copper or graphite.
3. external spiral structure sinker electric discharge machining method according to claim 1, it is characterised in that process gap according to external spiral structure and threaded hole is processed gap and calculated the processing dimension of the tool-electrode that need to process.
4. external spiral structure sinker electric discharge machining method according to claim 3, it is characterized in that, described tool-electrode includes the tool-electrode of two kinds of precision according to external spiral structure machining accuracy, and wherein thick tool-electrode is that external spiral physical dimension amplifies 0.4��0.5mm; Essence tool-electrode is that external spiral physical dimension amplifies 0.1��0.2mm.
5. external spiral structure sinker electric discharge machining method according to claim 3, it is characterized in that, described tool-electrode includes the tool-electrode of three kinds of precision according to external spiral structure machining accuracy, and wherein thick tool-electrode is that external spiral physical dimension amplifies 0.4��0.5mm; Half essence tool-electrode is that external spiral physical dimension amplifies 0.2��0.3mm; Essence tool-electrode is that external spiral physical dimension amplifies 0.1��0.2mm.
6. external spiral structure sinker electric discharge machining method according to claim 2, it is characterised in that the method for machining plate-like material threaded hole electrode is that copper beats copper, alloyed copper beats alloyed copper or graphite beats graphite sinker electric discharge machining method.
7. external spiral structure sinker electric discharge machining method according to claim 1, it is characterised in that the method for machining plate-like material threaded hole electrode is:
(1) technique of alignment in Electric Discharge Machining is adopted to carry out being directed at and fixing the board-like material after preprocessing;
(2) with 3R fixture, tool-electrode is fixed on electric spark former spindle, adopts the technique of alignment in Electric Discharge Machining to carry out being directed at and demarcating;
(3) it is processed obtaining corresponding threaded hole to board-like material with tool-electrode.
8. the external spiral structure sinker electric discharge machining method according to any one of claim 4 or 5, it is characterised in that the method for machining plate-like material threaded hole electrode is:
(1) technique of alignment in Electric Discharge Machining is adopted to carry out being directed at and fixing the board-like material after preprocessing;
(2) with 3R fixture, different accuracy tool-electrode is fixed on electric spark former spindle, adopts the technique of alignment in Electric Discharge Machining to carry out being directed at and demarcating;
(3) it is processed obtaining corresponding different accuracy threaded hole to board-like material with different accuracy tool-electrode.
9. external spiral structure sinker electric discharge machining method according to claim 1, it is characterised in that be according to the method for board-like material threaded hole electrode machining external spiral structure:
(1) the external spiral structure crude green body after preprocessing is placed on electric spark former spindle, adopts the technique of alignment in Electric Discharge Machining to carry out being directed at and demarcating;
(2) utilization is counter copies mould processing method, utilizes board-like material threaded hole electrode to adopt edm forming technology processing external spiral structure.
10. external spiral structure sinker electric discharge machining method according to claim 8, it is characterised in that be according to the method for board-like material threaded hole electrode machining external spiral structure:
(1) the external spiral structure crude green body after preprocessing is placed on electric spark former spindle, adopts the technique of alignment in Electric Discharge Machining to carry out being directed at and demarcating;
(2) utilization is counter copies mould processing method, utilizes the threaded hole of different accuracy on board-like material threaded hole electrode to adopt edm forming technology processing external spiral structure successively.
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| CN107350581A (en) * | 2017-07-07 | 2017-11-17 | 安徽宁国中鼎模具制造有限公司 | A kind of automobile engine cover buffer stopper mould molding machined electrode structure |
| CN109365930B (en) * | 2018-11-20 | 2020-04-17 | 广东轻工职业技术学院 | Electric spark machining device and method for spatial spiral hole |
| CN111283923B (en) * | 2020-02-13 | 2022-03-11 | 河南科技大学 | Method for shaping and processing plastic cement tooth-direction drum-shaped gear |
| CN113523910A (en) * | 2021-06-22 | 2021-10-22 | 合肥聚能电物理高技术开发有限公司 | Hole groove machining method for tungsten-copper composite board and tungsten-copper composite board |
| CN113814491B (en) * | 2021-10-14 | 2023-01-06 | 天津航天机电设备研究所 | Processing method of three-head screw transmission pair for spacecraft mechanism |
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