A method and system for preparing micro-tool electrodes online

Abstract

The present invention relates to an online preparation method and preparation system for a micro-tool electrode, and belongs to the field of micro-special processing technology. The main steps of trimming the electrode include: through one tool setting, the spindle module servo feeds along the z-axis direction at a horizontally equally divided angle to obtain a prismatic rough-trimmed blank; through one tool setting, the spindle module continuously rotates and servo feeds along the z-axis direction to obtain a cylindrical semi-finishing electrode; through one tool setting, the spindle module continuously rotates and unidirectionally feeds along the Z-axis direction to obtain a cylindrical fine-finishing micro-tool electrode. Through three trimming processes, the overall processing time is shortened, the burr generation rate is reduced, and the problem of inconsistent trimming height of the root of the micro-tool electrode caused by eccentricity is solved.

Description

Technical Field

[0001] The invention relates to the technical field of electrode processing, and in particular to an online preparation method and preparation system for a tool electrode. Background Art

[0002] Micro-EDM technology has the advantages of non-contact, high precision, no burrs, and can be processed after heat treatment. It is suitable for the precision manufacturing of small structural parts of conductive materials. In order to avoid the secondary clamping error and micro-operation difficulty of the slender electrode wire with low stiffness, the micro-tool electrode (radial size <100μm) needs to be made online. Considering the low stiffness of the slender micro-tool electrode, the micro-tool electrode made online should not be too long, otherwise it will affect the processing accuracy and efficiency of the micro-structure. Moreover, due to the serious loss problem in the use of micro-tool electrodes, the micro-tool electrode needs to be made online again after a period of use.

[0003] At present, the wire discharge grinding (WEDG) method mainly uses a rotating spindle head to clamp a shorter section of bar stock, and online manufactures a section of micro tool electrode for micro EDM. During the micro EDM process, the micro tool electrode will continue to wear out axially. When the micro tool electrode wears out until the length of this shorter bar stock is insufficient, it is necessary to manually re-clamp a section of bar stock and repeat the above process. This operation process is not only inefficient, but also easy to introduce secondary clamping errors. It cannot meet the high-precision and high-efficiency requirements of batch processing of tiny structures in industrial applications, which limits the application and development of micro EDM technology.

[0004] In order to meet the needs of repeated online WEDG production and use of fine tool electrodes, there is a spindle head mechanism that can realize the composite functions of rotating and creeping feeding of thinner (Φ0.1-0.2mm) long electrode (300-500mm) rods. However, due to the processing and manufacturing errors and assembly errors of the spindle itself and the installation errors of the fine tool electrode rods, it is impossible to fully guarantee the coaxiality of the axis of the fine tool electrode rod and the axis of rotation of the spindle, resulting in inevitable eccentricity errors in the installation of the tool electrode rod. This causes the distance between the geometric center of the fine tool electrode and the wire trimming point at the tip of the WEDG guide piece to change in real time during the WEDG process of the fine tool electrode when the spindle rotates, that is, the actual processing amount changes with the rotation of the spindle. Therefore, when the z-axis downward servo feed is controlled for online wire trimming while the spindle rotates, it is easy to cause uneven removal of the various processing surfaces of the fine tool electrode and unevenness of the root of the fine tool electrode. At the same time, the repeated servo advance and retreat of the tool electrode caused by the uneven removal reduces the processing efficiency. Summary of the invention

[0005] In view of the shortcomings of the above-mentioned existing production technologies, the applicant provides an online preparation method and preparation system for micro tool electrodes, thereby dividing the dressing process of micro tool electrodes into three stages: rough dressing, semi-finishing and fine dressing. Through single-sided processing of rough dressing, repeated processing caused by the inevitable eccentricity error between the micro tool electrode and the spindle is prevented, thereby solving the problems of online preparation errors and low efficiency caused by the rotational eccentricity error of the spindle.

[0006] The technical solution adopted by the present invention is as follows:

[0007] A method for preparing a micro-tool electrode comprises the following steps:

[0008] Step 1: Rough repair process: After one tool setting, the spindle module is servo-fed along the z-axis direction at a horizontally evenly divided angle and the spindle has no rotational motion, so as to obtain a prismatic rough repair blank;

[0009] Step 2: Semi-finishing process: through one tool setting, the spindle module is servo-fed along the z-axis direction and the spindle is continuously rotated to obtain a cylindrical semi-finishing electrode;

[0010] Step 3: Fine-tuning process: Through one tool setting, the spindle module is fed unidirectionally along the z-axis direction and the spindle is continuously rotated to obtain a cylindrical fine-tuning micro-tool electrode.

[0011] During the rough repair process of step 1, the specific steps of the spindle module servo feeding at a horizontal equally divided angle are as follows: the WEDG module moves along the positive direction of the x-axis, and the x-axis reading of the tangent point of the surface to be repaired of the tool electrode to be repaired is measured through electrical contact, and an additional movement feed amount S1 is added; the spindle module gradually moves downward along the z-axis until the tool electrode to be repaired contacts the wire repair electrode; the spindle module is controlled to servo feed along the z-axis direction without the spindle rotating, and the servo feed is fed to the set processing length; the WEDG module is controlled to move along the negative direction of the x-axis to reserve a tool setting safety distance; the spindle module is lifted upward along the z-axis to the position to be repaired, and the spindle rotates through a horizontal equally divided angle θ; and then the above process is repeated until material is removed around the circumference of the tool electrode to be repaired.

[0012] During the semi-finishing process of step 2, the specific steps of the continuous rotation servo feed of the spindle module along the z-axis direction are as follows: the WEDG module moves along the positive direction of the x-axis, and the x-axis reading of the tangent point of the surface to be repaired of the tool electrode to be repaired is measured through electrical contact, and an additional movement feed amount S2 is added; the spindle module gradually moves downward along the z-axis until the tool electrode to be repaired contacts the wire repairing electrode; the spindle module is servo-fed along the z-axis and the spindle continuously rotates, and the servo feed is until the set processing length; the WEDG module moves along the negative direction of the x-axis to reserve a tool setting safety distance; the spindle module moves upward along the z-axis to the position to be repaired.

[0013] During the step three finishing process, the specific steps of the spindle module continuously rotating and feeding in one direction along the z-axis are as follows: the WEDG module moves along the positive direction of the x-axis, and measures the x-axis reading of the tangent point of the surface to be repaired of the tool electrode to be repaired through electrical contact, and an additional moving feed amount S3 is added; the spindle module gradually moves downward along the z-axis until the tool electrode to be repaired contacts the wire repairing electrode; the spindle module continues to feed downward along the z-axis and the spindle continuously rotates until the set processing length; the WEDG module moves along the negative direction of the x-axis to reserve a tool setting safety distance; the spindle module moves upward along the z-axis to the position to be repaired.

[0014] The specific steps for tool setting are:

[0015] Step 1: The WEDG module moves to the negative position of the y-axis relative to the spindle module, and a safe tool distance is maintained between the wire trimming electrode and the electrode of the micro-tool to be repaired. The spindle module moves downward along the z-axis until the end of the electrode of the micro-tool to be repaired is coplanar with the wire trimming electrode; the WEDG module moves along the positive direction of the y-axis until the wire trimming electrode is in electrical contact with the electrode of the micro-tool to be repaired. At this time, the y-axis position y1 of the WEDG module relative to the frame is measured; the spindle module moves upward along the z-axis until a safe tool distance is maintained between the end of the electrode of the micro-tool to be repaired and the wire trimming electrode;

[0016] Step 2: The WEDG module moves to the positive position of the y-axis relative to the spindle module. During the movement, the WEDG module and the x-axis position in step 1 are kept unchanged, and a safe tool distance is maintained between the wire trimming electrode and the electrode of the micro-tool to be repaired; the spindle module moves downward along the z-axis until the end of the electrode of the micro-tool to be repaired is coplanar with the wire trimming electrode, and then the WEDG module is controlled to move in the negative direction of the y-axis until the wire trimming electrode is in electrical contact with the electrode of the micro-tool to be repaired. At this time, the y-axis position y2 of the WEDG module relative to the frame is measured. After the reading is measured, the spindle module is moved upward along the z-axis until a safe tool distance is maintained between the end of the electrode of the micro-tool to be repaired and the wire trimming electrode;

[0017] Step 3: The y-axis reading of the actual geometric center position of the fine tool electrode to be repaired is measured by steps 1 and 2. This reading value satisfies the following formula:

[0018]

[0019] Wherein, Y is the y-axis reading value of the actual geometric center position of the micro-tool electrode to be repaired; y1 is the y-axis reading value of the edge contact point of the micro-tool electrode to be repaired along the negative direction of the y-axis obtained in step 1; y2 is the y-axis reading value of the edge contact point of the micro-tool electrode to be repaired along the positive direction of the y-axis obtained in step 2;

[0020] Move the WEDG module to the y-axis reading of the actual center position of the micro-tool electrode to be repaired. The WEDG module as a whole is in the negative x-axis position relative to the spindle module, and the wire trimming electrode at the tip of the wire trimming guide block is at a safe distance from the micro-tool electrode to be repaired. Then control the WEDG module to move along the positive x-axis until the wire trimming electrode at the tip of the wire trimming guide block is in electrical contact with the micro-tool electrode to be repaired. At this time, the x-axis position X of the WEDG module relative to the frame is measured, which is the x-axis reading of the tangent point of the surface to be repaired of the micro-tool electrode to be repaired. After the reading is measured, move the WEDG module along the negative x-axis to the safe distance between the wire trimming electrode at the tip of the wire trimming guide block and the micro-tool electrode to be repaired, and then move the spindle module upward along the z-axis to the position to be repaired.

[0021] The single feed amounts of feed S1, S2 and S3 are all less than 1 / 2 of the wire trimming electrode diameter D1, and S1>S2>S3.

[0022] S1, S2, and S3 also satisfy the following formula:

[0023] s1+s2+s3=D0-D (3)

[0024] Where D0 is the original diameter of the micro-tool electrode to be repaired; D is the diameter of the micro-tool electrode to be repaired after fine-tuning. The vertical distance ΔL between each vertex formed by rough-trim and the outer edge of the micro-tool electrode to be repaired after semi-fine-trim satisfies the following formula:

[0025]

[0026] Where, θ is the horizontal indexing angle during the rough repair process, D0 is the original diameter of the micro-tool electrode to be repaired; D1 is the diameter of the wire repair electrode, S1, S2, S3 are the feed amounts during the rough repair, semi-finishing, and fine repair processes;

[0027] The horizontal equally divided angle θ satisfies the following formula:

[0028]

[0029] In the formula, n is the number of equal parts the circumference is divided into, and n is a positive integer;

[0030] Substituting formula (5) into formula (4), we get the following formula for evaluating n:

[0031]

[0032] In the actual working environment, the upper limit of n is determined by referring to the processing time of each horizontal indexing surface and the total roughing processing time. The upper limit of n satisfies the following formula:

[0033]

[0034] Where T is the total time for rough machining; t is the machining time for each horizontal indexing surface.

[0035] A preparation system for a micro-tool electrode preparation method, comprising a WEDG module moving along an x-axis and / or a y-axis, and a spindle module moving along a z-axis, wherein the WEDG module and the spindle module are both arranged on a frame;

[0036] The WEDG module includes a wire trimming guide block and a wire trimming electrode. The wire trimming guide block is fixed on the WEDG module. The wire trimming electrode is tensioned by guide wheels at various locations on the WEDG module and winds around the tip of the wire trimming guide block. The spindle module is fixed with a micro-tool electrode to be trimmed.

[0037] The beneficial effects of the present invention are as follows:

[0038] The present invention divides the trimming process of the micro tool electrode into three stages: rough trimming, semi-finishing and finishing. The rough machining method of continuous rotation relative to the main shaft and servo feeding along the normal direction of the z-axis can shorten the time for rough trimming of the micro tool electrode. At the same time, since the rough trimming adopts single-sided machining, the eccentricity error that inevitably exists between the micro tool electrode and the main shaft can be prevented from causing repeated servo machining at different distances, thereby improving the overall machining efficiency, shortening the overall machining time, and ensuring that the trimming height of the root of the micro tool electrode is consistent.

[0039] The present invention uses a three-step electrical contact alignment process to enable the wire trimming electrode at the tip of the wire trimming guide block to be accurately aligned with the surface to be repaired corresponding to the actual geometric center of the micro-tool electrode to be repaired in the three processing stages of rough trimming, semi-finishing and fine trimming, thereby ensuring that the geometric center of the micro-tool electrode after trimming coincides with the actual rotation center.

[0040] The present invention can prevent the micro-tool electrode to be repaired from colliding with the tip of the wire trimming guide block and bending during the trimming process by controlling the single feeding amount to be less than 1 / 2 of the wire trimming electrode diameter D1.

[0041] The present invention sets the horizontal equally divided angle θ to be 1 / n of the 360° circle and n is a positive integer, thereby ensuring that the processing time of each surface during the rough repair process is uniform and stable, and the overall processing time is predictable. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 It is an axonometric view of the overall mechanical structure of the present invention.

[0043] Figure 2 It is a partial enlarged view of the thread trimming part of the overall mechanical structure of the present invention.

[0044] Figure 3-1 It is a schematic diagram of the steps in which the wire repair guide block approaches the tool electrode to be repaired during the rough repair process of the present invention.

[0045] Figure 3-2 It is a schematic diagram of the steps in which the spindle module drives the electrode of the tool to be repaired to move downward during the rough repair process of the present invention.

[0046] Figure 3-3 It is a schematic diagram of the steps of cutting the tool electrode to be repaired during the rough repair process of the present invention.

[0047] Figure 3-4 It is a schematic diagram of the steps of retracting the wire trimming guide block during the rough trimming process of the present invention.

[0048] Figure 3-5 It is a schematic diagram of the steps of moving the main shaft upward during the rough repair process of the present invention.

[0049] Figure 3-6 It is a schematic diagram of the steps of the spindle rotating through a horizontal equally divided angle θ during the rough repair process of the present invention.

[0050] Figure 4 It is a schematic diagram of the original cross-sectional shape of the electrode to be repaired according to the present invention.

[0051] Figure 5 It is a schematic diagram of the feed amount of a single indexing surface in the rough repair process of the present invention.

[0052] Figure 6 It is a schematic diagram of the cross-sectional shape after rough repair of the present invention.

[0053] Figure 7-1 It is a schematic diagram of the semi-finishing tool setting steps in the present invention.

[0054] Figure 7-2 It is a schematic diagram of the steps of moving down the semi-finishing spindle module in the present invention.

[0055] Figure 7-3 It is a schematic diagram of the steps of semi-finishing the tool electrode to be repaired in the present invention.

[0056] Figure 7-4 It is a schematic diagram of the semi-finishing tool withdrawal step in the present invention.

[0057] Figure 7-5 It is a schematic diagram of the steps of moving up the semi-finishing spindle module in the present invention.

[0058] Figure 8 It is a schematic diagram of the cross-sectional shape and feed amount of the semi-finishing of the electrode to be repaired according to the present invention.

[0059] Figure 9-1 It is a schematic diagram of the fine tool setting steps in the present invention.

[0060] Figure 9-2 It is a schematic diagram of the steps of downward movement of the spindle module during the fine finishing process of the present invention.

[0061] Figure 9-3It is a schematic diagram of the steps of fine-repairing the tool electrode to be repaired in the present invention.

[0062] Figure 9-4 It is a schematic diagram of the steps of fine finishing and retracting in the present invention.

[0063] Figure 9-5 It is a schematic diagram of the steps of moving the spindle module upward during the finishing process of the present invention.

[0064] Fig.10 It is a schematic diagram of the cross-sectional shape and feed amount of the electrode to be repaired after fine repairing of the present invention.

[0065] Fig.11 It is a schematic diagram of the parameters of the complete wire trimming process of the present invention.

[0066] Figure 12-1 It is a schematic diagram of the relative positions between the wire repair guide block and the electrode of the tool to be repaired before the negative tool setting on the y-axis of the present invention.

[0067] Figure 12-2 It is a schematic diagram of the relative position between the wire repair guide block and the electrode of the tool to be repaired after the negative tool alignment of the y-axis is completed in the present invention.

[0068] Figure 13-1 It is a schematic diagram of the relative positions between the wire repair guide block and the tool electrode to be repaired before the Y-axis positive tool alignment of the present invention.

[0069] Figure 13-2 It is a schematic diagram of the relative position between the wire repair guide block and the tool electrode to be repaired after the Y-axis forward knife of the present invention is completed.

[0070] Figure 14-1 It is a schematic diagram of the relative positions between the wire repair guide block and the tool electrode to be repaired before the x-axis tool alignment of the present invention.

[0071] Figure 14-2 It is a schematic diagram of the relative position between the wire repair guide block and the tool electrode to be repaired after the x-axis tool alignment of the present invention.

[0072] Figure 14-3 It is a schematic diagram of the step of retracting the tool after tool setting on the x-axis of the present invention.

[0073] Fig.15 It is a schematic diagram of the single feed amount value of the present invention.

[0074] Among them: 1. WEDG module; 2. Spindle module;

[0075] 101. Wire trimming guide block; 102. Wire trimming electrode;

[0076] 201. Micro tool electrode to be repaired. DETAILED DESCRIPTION

[0077] The specific implementation of the present invention will be described below in conjunction with the accompanying drawings.

[0078] A fine tool electrode online preparation system, such as Figure 1 and Figure 2 As shown, it includes a frame, on which a WEDG module 1 and a spindle module 2 are arranged, wherein the WEDG module 1 includes a wire trimming guide block 101 and a wire trimming electrode 102; the spindle module 2 includes a micro-tool electrode 201 to be trimmed.

[0079] The WEDG module 1 can move relative to the frame along the x and y axis directions, the rear of the spindle module 2 is fixed on the frame and can move relative to the frame along the z axis direction, and the spindle of the spindle module 2 has rotational freedom. The WEDG wire trimming guide block 101 is fixed to the WEDG module 1, and the WEDG wire trimming electrode 102 is tensioned by guide wheels at various locations on the WEDG module 1 and horizontally passes around the tip of the WEDG wire trimming guide block 101. The fine tool electrode 201 to be trimmed is fixed inside the spindle module 2 and rotates synchronously with the spindle.

[0080] A method for preparing a fine tool electrode using an online preparation system for a fine tool electrode includes three processing steps: rough trimming, semi-finishing, and finishing. Figures 3-1 to 3-6 As shown in the figure, it is the process of rough repairing the fine tool electrode, and the specific steps are: through one tool setting, the WEDG module 1 is controlled to move along the positive direction of the x-axis, and the x-axis reading of the intersection point of the surface to be repaired of the fine tool electrode 201 to be repaired is measured through electrical contact. At this time, the WEDG module 1 adds the moving feed amount S1; the spindle module 2 is controlled to move gradually downward along the z-axis until the fine tool electrode 201 to be repaired contacts the WEDG wire trimming electrode 102; the spindle module 2 is controlled to servo feed along the z-axis direction without the spindle rotating, and the servo feed is performed until the set processing length; the WEDG module 1 is controlled to move along the negative direction of the x-axis until the WEDG wire trimming electrode 102 at the tip of the WEDG wire trimming guide block 101 is at a safe distance from the fine tool electrode 201 to be repaired; the spindle module 2 is controlled to move upward along the z-axis to the position to be repaired; and the spindle is rotated by a horizontally equally divided angle of θ. Repeat the above operation until all the materials are removed around the electrode circle of the tool to be repaired, and each indexing surface to be repaired is processed. Finally, the spindle is rotated horizontally to an angle of θ to the initial processing position.

[0081] like Figure 4 , Figure 5 and Figure 6 As shown, respectively, are the original cross-sectional shape of the micro tool electrode 201 to be repaired, the feed amount of a single dividing surface during the rough repair process, and the cross-sectional shape after the rough repair in the online preparation method of the micro tool electrode considering the spindle rotation eccentricity error according to an embodiment of the present invention. The original cross-sectional shape of the micro tool electrode 201 to be repaired is a cylinder with a diameter of D0, the feed amount of a single dividing surface during the rough repair process is S1, and the cross-sectional shape of the micro tool electrode after the rough repair is a regular polygon.

[0082] like Figures 7-1 to 7-5 The figure shows the machining process of semi-finishing micro-tool electrode. Through one tool setting, the WEDG module 1 is controlled to move along the positive direction of the x-axis, and the x-axis reading of the tangent point of the surface to be repaired of the micro-tool electrode 201 to be repaired is measured through electrical contact, and the moving feed amount S2 is added; the spindle module 2 is controlled to move gradually downward along the z-axis until the micro-tool electrode 201 to be repaired contacts the wire trimming electrode 102; the spindle module 2 is controlled to servo feed along the z-axis and the spindle is continuously rotated, and the servo feed is until the set machining length; the WEDG module 1 is controlled to move along the negative direction of the x-axis until the wire trimming electrode 102 at the tip of the wire trimming guide block 101 keeps a safe distance from the micro-tool electrode 201 to be repaired; the spindle module 2 is controlled to move upward along the z-axis to the position to be repaired.

[0083] like Figure 8 As shown, according to the online preparation method of a micro tool electrode taking into account the spindle rotation eccentricity error, the semi-finishing cross-sectional shape and feed amount of the micro tool electrode 201 to be repaired are shown. The feed amount during the semi-finishing process is S2, and the cross-sectional shape of the repaired micro tool electrode is circular.

[0084] like Figures 9-1 to 9-5 The figure shows the specific process of fine-trim the micro-tool electrode of the present invention. Through one tool setting, the WEDG module 1 is controlled to move in the positive direction of the x-axis, and the x-axis reading of the tangent point of the surface to be repaired of the micro-tool electrode 201 to be repaired is measured through electrical contact, and the moving feed amount S3 is added; the spindle module 2 is controlled to gradually move downward along the z-axis until the micro-tool electrode 201 to be repaired contacts the wire trimming electrode 102; the spindle module 2 is controlled to continuously feed downward along the z-axis and the spindle is continuously rotated until the set processing length; the WEDG module 1 is controlled to move in the negative direction of the x-axis until the wire trimming electrode 102 at the tip of the wire trimming guide block 101 keeps a safe distance from the micro-tool electrode 201 to be repaired; the spindle module 2 is controlled to move upward along the z-axis to the position to be repaired.

[0085] like Fig.10 As shown, according to the online preparation method of a micro tool electrode taking into account the spindle rotation eccentricity error, the cross-sectional shape and feed amount of the micro tool electrode 201 to be repaired are refined. The feed amount during the refinement process is S3, and the cross-sectional shape of the repaired micro tool electrode is circular.

[0086] like Fig.11 As shown, the complete wire trimming process parameters of the online preparation method of a micro-tool electrode considering the spindle rotation eccentricity error according to an embodiment of the present invention.

[0087] In the above steps, the specific process of tool setting is as follows:

[0088] like Figure 12-1 , Figure 12-2As shown, it is a schematic diagram of the process of tool setting step one, the WEDG module 1 is controlled to move to the negative position of the y-axis relative to the spindle module 2, and the wire trimming electrode 102 of the wire trimming guide block 101 along the positive direction of the y-axis is kept at a safe distance from the micro-tool electrode 201 to be trimmed, and the spindle module 2 is moved downward along the z-axis until the end of the micro-tool electrode 201 to be trimmed and the wire trimming electrode 102 of the wire trimming guide block 101 along the positive direction of the y-axis are in the same plane; then the WEDG module 1 is controlled to move along the positive direction of the y-axis until the wire trimming electrode 102 of the wire trimming guide block 101 along the positive direction of the y-axis is electrically contacted with the micro-tool electrode 201 to be trimmed; at this time, the y-axis position y1 of the WEDG module 1 relative to the frame is measured, and after the reading is measured, the spindle module 2 is moved upward along the z-axis until a safe distance is maintained between the end of the micro-tool electrode 201 to be trimmed and the wire trimming electrode 102 of the wire trimming guide block 101 along the positive direction of the y-axis.

[0089] As shown in FIG13 , the specific process of the tool setting step 2 is as follows: control the WEDG module 1 to move to the positive position of the y-axis relative to the spindle module 2, keep the x-axis position of the WEDG module 1 unchanged during the movement and keep a safe distance between the wire trimming electrode 102 of the wire trimming guide block 101 along the negative direction of the y-axis and the micro-tool electrode 201 to be trimmed, move the spindle module 2 downward along the z-axis to the end of the micro-tool electrode 201 to be trimmed and the wire trimming guide block 101 along the negative direction of the y-axis. The wire electrodes 102 are in the same plane, and then the WEDG module 1 is controlled to move in the negative direction of the y-axis until the wire electrode 102 of the wire trimming guide block 101 along the negative direction of the y-axis is in electrical contact with the micro-tool electrode 201 to be trimmed. At this time, the y-axis position y2 of the WEDG module 1 relative to the frame can be measured. After the reading is measured, the spindle module 2 is moved upward along the z-axis to a safety distance reserved between the end of the micro-tool electrode 201 to be trimmed and the wire trimming electrode 102 of the wire trimming guide block 101 along the negative direction of the y-axis.

[0090] As shown in FIG. 14 , the specific process of the tool setting step 3 is as follows: the y-axis reading of the actual geometric center position of the micro-tool electrode 201 to be repaired is measured by the tool setting step 1 and the tool setting step 2, and the reading value satisfies formula (1), which is as follows:

[0091]

[0092] Wherein, Y is the y-axis reading value of the actual geometric center position of the micro-tool electrode 201 to be repaired; y1 is the y-axis reading value of the edge contact point of the micro-tool electrode 201 to be repaired along the negative direction of the y-axis obtained by the tool setting step 1; y2 is the y-axis reading value of the edge contact point of the micro-tool electrode 201 to be repaired along the positive direction of the y-axis obtained by the tool setting step 2.

[0093] Move the WEDG module 1 to the y-axis reading of the actual center position of the micro-tool electrode 201 to be repaired, the WEDG module 1 as a whole is in the negative x-axis position relative to the spindle module 2, and reserve a safe distance between the wire trimming electrode 102 at the tip of the wire trimming guide block 101 and the micro-tool electrode 201 to be repaired, then control the WEDG module 1 to move in the positive x-axis direction until the wire trimming electrode 102 at the tip of the WEDG wire trimming guide block 101 is in electrical contact with the micro-tool electrode 201 to be repaired, at this time, the x-axis position X of the WEDG module 1 relative to the frame can be measured, that is, the x-axis reading of the intersection point of the surface to be repaired of the micro-tool electrode 201 to be repaired, after measuring the reading, move the WEDG module 1 in the negative x-axis direction to the safe distance between the wire trimming electrode 102 at the tip of the wire trimming guide block 101 and the micro-tool electrode 201 to be repaired, and then move the spindle module 2 upward along the z-axis to the position to be repaired.

[0094] Through the tool alignment process of the above three steps, the wire trimming electrode 102 at the tip of the wire trimming guide block 101 can be accurately aligned with the surface to be trimmed corresponding to the actual geometric center of the trimming micro-tool electrode in the three processing stages of rough trimming, semi-finishing and finishing, ensuring that the geometric center of the trimming micro-tool electrode coincides with the actual rotation center.

[0095] The following describes the method of determining the single feed amount with reference to the accompanying drawings:

[0096] like Fig.15 As shown, in the single feed amount value method, the single feed amounts S1, S2, and S3 should all be less than 1 / 2 of the diameter D1 of the wire trimming electrode 102, and S1>S2>S3, that is, satisfying formula (2), which is as follows:

[0097]

[0098] S1, S2, and S3 should also satisfy formula (3), which is as follows:

[0099] s1+s2+s3=D0-D (3)

[0100] Wherein, D0 is the original diameter of the micro-tool electrode 20101 to be repaired; D is the diameter of the micro-tool electrode 20101 to be repaired after fine-tuning.

[0101] The vertical distance △L between each vertex formed by rough trimming and the outer edge of the semi-finished fine tool electrode 201 to be trimmed should also be less than 1 / 2 of the diameter D1 of the trimming electrode 102. From the geometric relationship, it can be obtained that its value should satisfy formula (4), which is as follows:

[0102]

[0103] Where θ is the horizontal indexing angle during the rough repair process.

[0104] By controlling the single feed amount to be less than 1 / 2 of the diameter D1 of the wire trimming electrode 102, it is possible to prevent the fine tool electrode 201 to be trimmed from colliding with the tip of the wire trimming guide block 101 during the trimming process and bending, thereby affecting the trimming accuracy.

[0105] The following is a setting method for the horizontal equally divided angle of intermittent rotation during the rough repair process of the present invention:

[0106] like Fig.11 As shown, during the rough repair process, the setting method of the horizontal equally divided angle of the intermittent rotation is that the horizontal equally divided angle is θ, where θ is 1 / n of the 360° circle, and n is a positive integer, that is, it satisfies formula (5), which is as follows:

[0107]

[0108] Substituting formula (5) into formula (4) can obtain the lower limit of n, which satisfies formula (6). Formula (6) is as follows:

[0109]

[0110] In the actual working environment, the upper limit of n can be determined by referring to the processing time of each horizontal indexing surface and the total roughing processing time. The upper limit of n satisfies formula (7), which is as follows:

[0111]

[0112] Where T is the total time for rough machining; t is the machining time for each horizontal indexing surface.

[0113] By setting the horizontal equally divided angle θ to 1 / n of the 360° circle and n to be a positive integer, it can be ensured that the processing time of each surface during the rough repair process is uniform and stable, and the overall processing time is predictable.

[0114] The present invention divides the trimming process of the micro tool electrode into three stages: rough trimming, semi-finishing and finishing. The rough machining method of continuous rotation relative to the main shaft and servo feeding along the normal direction of the z-axis can reduce the machining amount in the rough trimming stage and shorten the time for rough trimming of the micro tool electrode. At the same time, since the rough trimming adopts single-sided machining, the eccentricity error that inevitably exists between the micro tool electrode and the main shaft can be prevented from causing repeated servo machining at different distances, which in turn improves the overall machining efficiency, shortens the overall machining time, and ensures that the trimming height of the root of the micro tool electrode is consistent. At the same time, the subsequent semi-finishing and finishing processes effectively reduce the generation rate of burrs.

Claims

1. A method for online preparation of a micro-tool electrode, characterized in that: The steps include: Step 1: Roughing process: through one tool setting, the spindle module (2) is servo-fed along the z-axis direction at a horizontally evenly divided angle and the spindle does not rotate, so as to obtain a prismatic rough-cut blank; Step 2: Semi-finishing process: through one tool setting, the spindle module (2) is servo-fed along the z-axis direction and the spindle is continuously rotated to obtain a cylindrical semi-finishing electrode; Step 3: Fine-tune process: after one tool setting, the spindle module (2) is fed unidirectionally along the z-axis direction and the spindle is continuously rotated to obtain a cylindrical fine-tune tool electrode; during step 1: rough-tune process, the spindle module (2) is servo-fed at a horizontally equally divided angle. The specific steps are: the WEDG module (1) moves along the positive x-axis, and the x-axis reading of the tangent point of the to-be-tended surface of the tool electrode to be repaired is measured through electrical contact, and the additional movement feed amount S1 is added; the spindle module (2) gradually moves downward along the z-axis until the tool electrode to be repaired contacts the wire-tightening electrode (102); the spindle module (2) is controlled to move in a straight line; the spindle module (2) is moved ... The block (2) is servo-fed along the z-axis direction and the spindle does not rotate, and the servo feed is fed to the set processing length; the WEDG module (1) is controlled to move along the negative direction of the x-axis to the reserved tool setting safety distance; the spindle module (2) is lifted along the positive direction of the z-axis to the position to be repaired, and the spindle rotates through a horizontally divided angle θ; then the above process is repeated until material is removed around the electrode circle of the tool to be repaired; Step 2 During the semi-finishing process, the spindle module (2) continuously rotates along the z-axis direction. The specific steps of servo feeding are as follows: the WEDG module (1) moves along the positive direction of the x-axis, and the electrical contact is The x-axis reading of the tangent point of the tool electrode to be repaired and the surface to be repaired is measured, and the additional moving feed amount S2 is added; the spindle module (2) gradually moves downward along the z-axis until the tool electrode to be repaired contacts the wire repair electrode (102); the spindle module (2) servo feeds along the z-axis and the spindle continuously rotates and moves the spindle, and the servo feeds until the set processing length; the WEDG module (1) moves along the negative direction of the x-axis to reserve a tool setting safety distance; the spindle module (2) moves upward along the z-axis to the position to be repaired; during the step three fine repair process, the spindle module (2) continuously rotates unidirectionally along the z-axis direction. The specific steps of feeding are as follows: the WEDG module (1) moves along the positive direction of the x-axis, measures the x-axis reading of the tangent point of the tool electrode to be repaired on the surface to be repaired through electrical contact, and adds a moving feed amount S3; the spindle module (2) gradually moves downward along the z-axis until the tool electrode to be repaired contacts the wire repairing electrode (102); the spindle module (2) continuously feeds downward along the z-axis and the spindle continuously rotates until the set processing length is reached; the WEDG module (1) moves along the negative direction of the x-axis to a reserved tool setting safety distance; the spindle module (2) moves upward along the z-axis to the position to be repaired.

2. The method for online preparation of a micro-tool electrode according to claim 1, characterized in that: The specific steps for tool setting are: Step 1: The WEDG module (1) moves to a negative position on the y-axis relative to the spindle module (2), and a safe tool distance is maintained between the wire trimming electrode (102) and the micro-tool electrode (201) to be trimmed, and the spindle module (2) moves downward along the z-axis until the end of the micro-tool electrode (201) to be trimmed is coplanar with the wire trimming electrode (102); the WEDG module (1) moves along the y-axis positive direction until the wire trimming electrode (102) and the micro-tool electrode (201) to be trimmed are in electrical contact, at which time the y-axis position y1 of the module relative to the frame is measured; the spindle module (2) moves upward along the z-axis until a safe tool distance is maintained between the end of the micro-tool electrode (201) to be trimmed and the wire trimming electrode (102); Step 2: The WEDG module (1) moves to a positive position on the y-axis relative to the spindle module (2), and during the movement, the x-axis position of the WEDG module (1) and step 1 is kept unchanged, and a safe tool distance is maintained between the wire trimming electrode (102) and the micro-tool electrode (201) to be repaired; the spindle module (2) moves downward along the z-axis until the end of the micro-tool electrode (201) to be repaired is coplanar with the wire trimming electrode (102), and then the WEDG module (1) is controlled to move in the negative direction of the y-axis until the wire trimming electrode (102) and the micro-tool electrode (201) to be repaired are in electrical contact, at which time the y-axis position y2 of the WEDG module (1) relative to the frame is measured, and after the reading is measured, the spindle module (2) is moved upward along the z-axis until a safe tool distance is maintained between the end of the micro-tool electrode (201) to be repaired and the wire trimming electrode (102); Step 3: The y-axis reading of the actual geometric center position of the fine tool electrode to be repaired is measured by steps 1 and 2. This reading value satisfies the following formula: Wherein, Y is the y-axis reading value of the actual geometric center position of the micro-tool electrode (201) to be repaired; y1 is the y-axis reading value of the edge contact point of the micro-tool electrode (201) to be repaired along the negative direction of the y-axis obtained in step 1; y2 is the y-axis reading value of the edge contact point of the micro-tool electrode (201) to be repaired along the positive direction of the y-axis obtained in step 2; The WEDG module (1) is moved to the y-axis reading of the actual center position of the micro-tool electrode (201) to be repaired, the WEDG module (1) is in the negative x-axis position relative to the spindle module (2), and the wire trimming electrode (102) at the tip of the wire trimming guide block (101) is at a safe distance from the micro-tool electrode (201) to be repaired, and then the WEDG module (1) is controlled to move along the positive x-axis until the wire trimming electrode (102) at the tip of the wire trimming guide block (101) is at a safe distance from the micro-tool electrode (201) to be repaired. ) is in electrical contact with the micro-tool electrode (201) to be repaired, and at this time, the x-axis position X of the WEDG module (1) relative to the frame is measured, which is the x-axis reading of the tangent point of the micro-tool electrode (201) to be repaired. After the reading is measured, the WEDG module (1) is moved along the negative direction of the x-axis to a safe distance between the wire repairing electrode (102) at the tip of the wire repairing guide block (101) and the micro-tool electrode (201) to be repaired, and then the spindle module (2) is moved upward along the z-axis to the position to be repaired.

3. The method for online preparation of a micro-tool electrode according to claim 1, characterized in that: The single feeding amounts of feeding amounts S1, S2 and S3 are all less than 1 / 2 of the diameter D1 of the wire trimming electrode (102), and S1>S2>S3.

4. The method for online preparation of a micro-tool electrode according to claim 1, characterized in that: S1, S2, and S3 also satisfy the following formula: s1+s2+s3=D0-D (3) In the formula, D0 is the original diameter of the micro-tool electrode (201) to be repaired; and D is the diameter of the micro-tool electrode (201) to be repaired after fine-tuning.

5. The online preparation method of a micro-tool electrode according to claim 1, characterized in that: The vertical distance △L between each vertex formed by rough repair and the outer edge of the micro-tool electrode (201) to be repaired after semi-fine repair satisfies the following formula: Wherein, θ is the horizontal indexing angle during the rough repair process, D0 is the original diameter of the micro-tool electrode (201) to be repaired; D1 is the diameter of the wire repairing electrode (102), S1, S2, S3 are the feed amounts during the rough repair, semi-finishing, and fine repair processes; the horizontal equally divided angle θ satisfies the following formula: In the formula, n is the number of equal parts the circumference is divided into, and n is a positive integer; Substituting formula (5) into formula (4), we get the following formula for evaluating n: In the actual working environment, the upper limit of n is determined by referring to the processing time of each horizontal indexing surface and the total roughing processing time. The upper limit of n satisfies the following formula: Where T is the total time for rough machining; t is the machining time for each horizontal indexing surface.

6. A preparation system for the online preparation method of micro-tool electrode according to claim 1, characterized in that: It comprises a WEDG module (1) that moves along the x-axis and / or y-axis, and a spindle module (2) that moves along the z-axis, wherein the WEDG module (1) and the spindle module (2) are both arranged on a frame; The WEDG module (1) comprises a wire trimming guide block (101) and a wire trimming electrode (102); the wire trimming guide block (101) is fixed on the WEDG module (1); the wire trimming electrode (102) is tensioned by guide wheels at various locations on the WEDG module (1) and is wound around the tip of the wire trimming guide block (101); and a micro-tool electrode (201) to be trimmed is fixed on the spindle module (2).

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