Eccentricity compensation method and device for machining of rotating shaft of spark machine and spark machine

Abstract

The invention discloses a spark machine rotating shaft machining eccentricity compensation method and device and a spark machine. The method comprises the following steps: determining a rotating center of a rotating shaft of the spark machine and an electrode mounted on the spark machine on a plane vertical to the rotating shaft of the spark machine; determining the offset of the rotation center of the electrode and the center of the rotation shaft of the spark machine on the plane; and compensating the position degree of the rotating shaft of the spark machine according to the offset. According to the scheme, the machining performance and the machining efficiency of the spark machine can be improved.

Description

Technical Field

[0001] The invention relates to the field of machine tools, and in particular to a method and device for compensating eccentricity in machining a rotating axis of a spark machine, and a spark machine. Background Art

[0002] Spark machine, also known as electrical discharge machine (EDM), is a mechanical processing equipment, widely used in the processing and manufacturing of various metal molds and mechanical equipment.

[0003] The EDM machine uses a special processing method to remove conductive materials by using the electro-erosion effect generated by pulse discharge between two electrodes immersed in the working fluid. When performing EDM machining, the tool electrode and the workpiece are respectively in contact with the two electrodes of the pulse power supply and immersed in the working fluid, or the working fluid is filled into the discharge gap. The tool electrode is fed to the workpiece through the gap automatic control system. When the gap between the two electrodes reaches a certain distance, the pulse voltage applied to the two electrodes breaks down the working fluid, generating spark discharge.

[0004] When using a spark machine to process gears and horn electrodes, the electrode rotation center must be concentric with the main shaft of the spark machine to achieve rotation processing. For gear processing, a small range of electrode misalignment can be achieved by adjusting the fixture to achieve electrode concentricity, which requires skilled workers to spend a lot of time. The processing requirements for horn electrodes are more stringent. Not only must the electrode design be concentric, but the electrode processing accuracy must be guaranteed to be within 0.02mm. Exceeding the tolerance may cause the electrode to be scrapped and affect the processing accuracy of mold parts.

[0005] The current spark machine has a certain eccentricity compensation function, but for the processing of horn electrodes, if the deviation between the rotation center of the horn electrode and the spindle center of the spark machine is large, it is difficult to use the existing spark machine for processing. Summary of the invention

[0006] The invention provides a method and device for compensating eccentricity of a rotating shaft of a spark machine, and a spark machine, which improve the processing performance of the spark machine and the processing efficiency of the spark machine.

[0007] According to one aspect of the present invention, a method for compensating for eccentricity of a rotating axis of a spark machine is provided, comprising:

[0008] Determine the rotation center of the spark machine rotation axis and the electrode installed on the spark machine on a plane perpendicular to the spark machine rotation axis;

[0009] Determine the offset between the rotation center of the electrode and the rotation axis center of the spark machine on the plane;

[0010] Compensate the position of the spark machine's rotating axis according to the offset.

[0011] According to another aspect of the present invention, there is provided an eccentricity compensation device for machining a rotating shaft of a spark machine, comprising:

[0012] A rotation center determination module, used to determine the rotation center of the spark machine rotation axis and the electrode installed on the spark machine on a plane perpendicular to the spark machine rotation axis;

[0013] An offset determination module is used to determine the offset between the rotation center of the electrode and the rotation axis center of the spark machine on a plane;

[0014] The compensation module is used to compensate the position of the rotating axis of the spark machine according to the offset.

[0015] According to another aspect of the present invention, there is provided a spark machine, comprising a spark machine body and an eccentricity compensation device for machining a rotating shaft of the spark machine;

[0016] An electrode is mounted on the rotating shaft of the spark machine body;

[0017] The eccentricity compensation device for machining a rotating shaft of a spark machine is used to perform eccentricity compensation on the rotating shaft of a spark machine body using the eccentricity compensation method for machining a rotating shaft of a spark machine according to any embodiment of the present invention.

[0018] The technical solution of the embodiment of the present invention is to determine the rotation center of the spark machine rotation axis and the electrode installed on the spark machine on a plane perpendicular to the spark machine rotation axis, then determine the offset between the rotation center of the electrode and the center of the spark machine rotation axis on the plane, and finally compensate the position of the spark machine rotation axis according to the offset, thereby realizing eccentricity compensation when the spark machine and the electrode are not concentric, increasing the possibility of using the spark machine for rotation processing and improving the processing efficiency of the spark machine.

[0019] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0021] Figure 1 Schematic diagram of the horn electrode designed for concentricity;

[0022] Figure 2 Schematic diagram of the horn electrode designed for non-concentricity;

[0023] Figure 3 A schematic flow chart of a method for compensating for eccentricity in machining a rotating shaft of a spark machine provided by an embodiment of the present invention;

[0024] Figure 4 A schematic flow chart of another method for compensating for eccentricity of a rotating shaft of a spark machine provided by an embodiment of the present invention;

[0025] Figure 5 A schematic diagram of the eccentricity compensation principle of the eccentricity compensation method for the rotating shaft of a spark machine provided by an embodiment of the present invention;

[0026] Figure 6 The present invention is a schematic structural diagram of an eccentricity compensation device for machining a rotating shaft of a spark machine provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0027] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0028] It should be noted that the terms "candidate", "target", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0029] The spark machine includes multiple axes that can rotate or move. The rotatable axis is generally called the C-axis, and the rotatable C-axis is used to install the electrode. A rectangular coordinate system is established on a plane perpendicular to the C-axis, and has two movable axial directions, the X-axis and the Y-axis. Traditional spark machine processing requires that the electrode installed on the rotating axis of the spark machine be concentric with the rotating axis to achieve rotational processing. In the case of a small range of non-concentricity, concentricity can be achieved by adjusting the jig, but this requires experienced operators to spend a lot of time, affecting processing efficiency. This also requires the electrode itself to be concentrically designed and have high processing accuracy. If the electrode processing accuracy is low or the electrode itself is non-concentrically designed, it may be difficult to achieve concentricity between the rotating axis of the spark machine and the electrode.

[0030] Concentric and non-concentric designs of electrodes Figure 1 and Figure 2 As shown, Figure 1 and Figure 2 Take the horn electrode as an example. Figure 1 Schematic diagram of the concentrically designed horn electrode. Figure 2 Schematic diagram of a non-concentric horn electrode. Figure 1 and Figure 2 As shown, the discharge end of the horn electrode is the tip of the horn. Figure 1 The rotation center of the horn electrode shown is concentric with the base. Figure 2 The rotation center of the horn electrode shown is not concentric with the base. Figure 1 or Figure 2 The bull-horn electrode shown in the figure may have its rotation center not concentric with the rotating axis of the spark machine when installed on the rotating axis of the spark machine. Although the concentrically designed bull-horn electrode can be concentric by manual adjustment, it takes a lot of time, while the non-concentrically designed bull-horn electrode is difficult to adjust concentrically.

[0031] The embodiment of the present invention provides a method for compensating for eccentricity of a rotating shaft of a spark machine, which is used to compensate for the eccentricity of a rotating shaft of a spark machine and an electrode.

[0032] Figure 3 A flow chart of a method for compensating eccentricity of a rotating shaft of a spark machine provided by an embodiment of the present invention is shown in FIG. Figure 3 As shown, the eccentricity compensation method for the rotating shaft of the spark machine provided in this embodiment includes:

[0033] Step S310, determining the rotation center of the spark machine rotation axis and the electrode installed on the spark machine on a plane perpendicular to the spark machine rotation axis.

[0034] The eccentricity compensation method for the spark machine rotating axis provided in the embodiment of the present invention is applied to the rotation processing of the spark machine. During the spark machine processing, the state of each of its own moving axes can be measured by the measurement system configured by itself, or an additional measurement system can be configured on the spark machine to measure the state of the spark machine during operation. In order to compensate for the eccentricity between the spark machine rotating axis and the electrode, it is necessary to first determine the eccentricity between the spark machine rotating axis and the electrode rotation center.

[0035] First, determine the rotation center of the spark machine rotation axis and the rotation center of the electrode installed on the spark machine on a plane perpendicular to the spark machine rotation axis. Except for the rotating C axis, the movable directions of the spark machine are all on the plane perpendicular to the rotation axis, that is, the X axis and the Y axis. Therefore, the deviation between the spark machine rotation axis and the rotation center of the electrode installed on the spark machine can be determined on the plane perpendicular to the spark machine rotation axis, and the compensation value on the plane can be calculated based on the determined deviation. Finally, the concentricity of the spark machine rotation axis and the electrode rotation center can be achieved by compensating the X axis and the Y axis on the plane.

[0036] The eccentricity compensation method for the rotating shaft of a spark machine provided in the embodiment of the present invention can be applied to the eccentricity compensation of electrodes with concentric design, and can also be applied to the eccentricity compensation of electrodes with non-concentric design, that is, it can be applied to Figure 1 or Figure 2 The electrode shown. And the eccentricity compensation method for the rotating axis of the spark machine provided by the embodiment of the present invention can be applied to a typical horn electrode.

[0037] Step S320, determining the offset between the rotation center of the electrode and the rotation axis center of the spark machine on the plane.

[0038] After the rotation center of the spark machine rotation axis and the rotation center of the electrode mounted on the spark machine are determined on a plane perpendicular to the spark machine rotation axis, the offset between the rotation center of the electrode and the rotation center of the spark machine rotation axis can be further determined on the plane. This offset can be a vector offset. Or, in order to facilitate subsequent compensation, the corresponding offset on the movable axial direction of the spark machine can be directly calculated.

[0039] Step S330, compensating the position of the rotating axis of the spark machine according to the offset.

[0040] After determining the offset between the rotation center of the electrode and the rotation axis center of the spark machine, the position of the rotation axis of the spark machine can be compensated according to the determined offset. That is, the determined offset is used as the compensation value of the movable axial direction, the rotation angle value of the C axis is used as the independent variable, and the offset generated by the X and Y axes of the corresponding electrode rotation center is used as the variable, that is, the electrode realizes dynamic compensation during the rotation process, and the rotation axis of the spark machine is concentric with the rotation center of the electrode. The method provided in this embodiment can compensate for the eccentricity of the spark machine only by measurement and judgment, without relying on the experience adjustment of skilled workers. At the same time, it can also compensate for the eccentricity of electrodes with non-concentric designs. It is suitable for various forms of electrodes, solves the pain point that the current electrode rotation center cannot be processed due to non-concentricity, and greatly improves the possibility and processing efficiency of using the spark machine for rotation processing.

[0041] Specifically, the offset is compensated into the spark machine rotating shaft so that the rotating shaft rotates around the rotation center of the electrode and remains concentric, that is, based on the rotation center of the electrode, the rotation center of the spark machine rotating shaft is compensated to be concentric with the rotation center of the electrode.

[0042] The eccentricity compensation method for the spark machine rotating axis provided in the present embodiment is achieved by determining the rotation center of the spark machine rotating axis and the electrode installed on the spark machine on a plane perpendicular to the spark machine rotating axis, then determining the offset between the rotation center of the electrode and the center of the spark machine rotating axis on the plane, and finally compensating the position of the spark machine rotating axis according to the offset, thereby realizing eccentricity compensation when the spark machine spindle and the electrode rotation center are not concentric, improving the possibility of using the spark machine for rotation processing, and improving the processing efficiency of the spark machine.

[0043] Figure 4 A flow chart of another method for compensating eccentricity of a rotating shaft of a spark machine provided by an embodiment of the present invention is shown in FIG. Figure 4 As shown, the eccentricity compensation method for the rotating shaft of the spark machine provided in this embodiment includes:

[0044] Step S410, determining the rotation center of the spark machine rotation axis and the electrode installed on the spark machine on a plane perpendicular to the spark machine rotation axis.

[0045] Step S420, determining the horizontal and vertical coordinate offsets between the rotation center of the electrode and the rotation axis center of the spark machine in a rectangular coordinate system of a plane perpendicular to the rotation axis of the spark machine.

[0046] Since the spark machine has two perpendicular movement directions, namely the X-axis and the Y-axis, on a plane perpendicular to the rotation axis, the horizontal and vertical coordinate offsets between the rotation center of the electrode and the rotation axis center of the spark machine can be determined in a rectangular coordinate system on a plane perpendicular to the rotation axis of the spark machine, where the horizontal and vertical coordinate offsets are the offsets on the X-axis and Y-axis of the spark machine.

[0047] Step S430, compensating the horizontal and vertical coordinate offsets of the spark machine rotation axis in a rectangular coordinate system perpendicular to the rotation axis plane.

[0048] After determining the horizontal and vertical coordinate offsets between the rotation center of the electrode and the rotation center of the spark machine in the rectangular coordinate system of the plane perpendicular to the rotation axis of the spark machine, the horizontal and vertical coordinates of the rotation axis of the spark machine in the rectangular coordinate system of the plane perpendicular to the rotation axis can be compensated for the horizontal and vertical coordinate offsets respectively, that is, the X-axis and Y-axis of the spark machine can be compensated for the determined horizontal and vertical coordinate offsets respectively, so that the rotation axis of the spark machine can be made concentric with the rotation center of the electrode.

[0049] It should be noted that the eccentricity compensation of the spark machine needs to be within a certain limit to ensure that the spark machine can work normally. After the eccentricity compensation of the spark machine is performed, although the rotating shaft of the spark machine can ensure that the rotating shaft is concentric with the rotation center of the electrode when it rotates, the electrode and the rotating shaft of the spark machine are not rotating concentrically as a whole. If the compensation value of the spark machine is too large, the non-concentricity is too high, which may cause damage to the spark machine or damage the workpiece being processed. Therefore, in an embodiment of the present invention, the absolute value of the horizontal and vertical coordinate offset of the spark machine is limited to less than or equal to 20mm. The compensation range of the rotation center offset of a traditional spark machine is within ±2mm. Therefore, even if the offset of the eccentricity compensation method for the spark machine rotating shaft provided in this application is limited to ±20mm, the compensation range of the rotation center offset is increased by an order of magnitude.

[0050] It should be noted that the method provided in this embodiment does not end the offset compensation of the spark machine once the offset to be compensated is determined, but it is an immediate compensation. This is because when the spark machine rotating axis rotates to different angles, the positional relationship between the spark machine rotating axis and the electrode rotation center is different, and the corresponding offset may also be different. Therefore, as the spark machine rotating axis rotates once with a preset rotation step, the offset between the electrode rotation center and the spark machine rotating axis center is determined on a plane perpendicular to the spark machine rotating axis, and then the angle of the spark machine rotating axis is compensated with the corresponding offset according to the preset rotation step. In addition, as the spark machine rotating axis rotates, the eccentricity compensation calculation and adjustment of the rotating axis are continuously performed. For the convenience of calculation, the offset between the electrode rotation center and the spark machine rotating axis center can be measured as the initial offset when the spark machine rotating axis is at the preset 0 degrees, and then the actual compensation corresponding to each angle is calculated based on the initial offset according to the actual rotation angle of the spark machine rotating axis. The eccentricity compensation of the rotating axis of the spark machine is calculated and compensated according to the preset step amount of the rotating axis of the spark machine. The smaller the preset step amount, the corresponding compensation value is calculated for each step amount, and the higher the processing accuracy is.

[0051] Figure 5 The schematic diagram of the eccentricity compensation principle of the eccentricity compensation method for the rotating shaft of the spark machine provided by the embodiment of the present invention is as follows: Figure 5 As shown, the rectangular coordinate system in the figure is established on a plane perpendicular to the rotation axis of the spark machine. The X-axis and Y-axis can be the two movable axes of the spark machine. Point O of the rectangular coordinate system is the rotation center of the C-axis of the spark machine, and point M in the figure is the rotation center of the electrode. When the rotation angle c of the C-axis of the spark machine is zero, the measurement system on the spark machine measures the offset (a, b) of the electrode rotation center M on the X-axis and Y-axis relative to the C-axis rotation center O. During the rotation of the C-axis, the offset of the C-axis rotation center O relative to the electrode rotation center M is represented by (p, q), where p = r*cos(θ+c), q = r*sin(θ+c), Eliminate r and θ, and we get p and q, where only the rotation angle c is a variable, and a and b are known quantities. That is, the compensation values ​​(p, q) of the X-axis and the Y-axis corresponding to the C-axis rotation angle c can be used to perform eccentric dynamic compensation.

[0052] The current spark machining is CNC machining, so the calculation method of the above compensation value can be added to the CNC program, and the above compensation value can be added to the X-axis and Y-axis in the CNC machining program to achieve compensation. And the compensation value is only related to the rotation angle of the C-axis, that is, at different rotation angles of the C-axis, the eccentricity dynamic compensation of the X-axis and Y-axis can be performed. Finally, after completing this machining, the eccentricity compensation value in the CNC program can be cancelled.

[0053] Figure 6 Schematic diagram of the structure of an eccentricity compensation device for a rotating shaft of a spark machine provided by an embodiment of the present invention. Figure 6 As shown, the device comprises:

[0054] The rotation center determination module 61 is used to determine the rotation center of the spark machine rotation axis and the electrode installed on the spark machine on a plane perpendicular to the spark machine rotation axis; the offset determination module 62 is used to determine the offset between the rotation center of the electrode and the center of the spark machine rotation axis on the plane; the compensation module 63 is used to compensate the position of the spark machine rotation axis according to the offset.

[0055] The eccentricity compensation device for the rotating shaft of the spark machine provided in this embodiment is used to achieve Figure 3 or Figure 4 The eccentricity compensation method for the C-axis machining of the spark machine shown in the figure has similar implementation principles and technical effects, which will not be repeated here.

[0056] The embodiment of the present invention also provides a spark machine, including a spark machine body and a spark machine rotating shaft processing eccentricity compensation device; the rotating shaft of the spark machine body is equipped with an electrode; the spark machine rotating shaft processing eccentricity compensation device is used to use Figure 3 or Figure 4 The eccentricity compensation method for the rotating shaft of the spark machine in the illustrated embodiment performs eccentricity compensation on the rotating shaft of the spark machine body.

[0057] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0058] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for compensating eccentricity of a rotating shaft of a spark machine, characterized in that: include: Determine the rotation center of the spark machine rotation axis and the electrode mounted on the spark machine on a plane perpendicular to the spark machine rotation axis; Determining the offset between the rotation center of the electrode and the rotation axis center of the spark machine on the plane; The position of the spark machine rotation axis is compensated according to the offset.

2. The method according to claim 1, characterized in that The method of compensating the position of the rotating axis of the spark machine according to the offset comprises: The offset is compensated into the spark machine rotation axis so that the rotation axis rotates around the rotation center of the electrode and remains concentric.

3. The method according to claim 1, characterized in that Determining the offset between the rotation center of the electrode and the rotation axis center of the spark machine on a plane perpendicular to the spark machine rotation axis includes: The horizontal and vertical coordinate offsets between the rotation center of the electrode and the rotation axis center of the spark machine are determined in a rectangular coordinate system of a plane perpendicular to the rotation axis of the spark machine.

4. The method according to claim 3, characterized in that The method of compensating the position of the rotating axis of the spark machine according to the offset comprises: The horizontal and vertical coordinates of the spark machine rotation axis in a rectangular coordinate system perpendicular to the rotation axis plane are respectively compensated for the horizontal and vertical coordinate offsets.

5. The method according to claim 3, characterized in that: The absolute value of the horizontal and vertical coordinate offset is less than or equal to 20 mm.

6. The method according to any one of claims 1 to 5, characterized in that: Determining the offset between the rotation center of the electrode and the rotation axis center of the spark machine on the plane includes: As the spark machine rotation axis rotates, the offset between the rotation center of the electrode and the rotation axis center of the spark machine is determined on the plane with a preset rotation step amount; According to the preset rotation step amount, the position of the spark machine rotation axis is compensated with a corresponding offset.

7. The method according to any one of claims 1 to 5, characterized in that: The electrodes are of concentric design, or the electrodes are of non-concentric design.

8. The method according to any one of claims 1 to 5, characterized in that: The electrode is a horn electrode.

9. An eccentricity compensation device for a rotating shaft of a spark machine, characterized in that: include: A rotation center determination module, used to determine the rotation center of the spark machine rotation axis and the electrode installed on the spark machine on a plane perpendicular to the spark machine rotation axis; An offset determination module, used to determine the offset between the rotation center of the electrode and the rotation axis center of the spark machine on the plane; A compensation module is used to compensate the position of the rotating axis of the spark machine according to the offset.

10. A spark machine, characterized in that: It includes a spark machine body and an eccentricity compensation device for processing a spark machine rotating shaft; An electrode is installed on the rotating shaft of the spark machine body; The eccentricity compensation device for the spark machine rotating shaft is used to perform eccentricity compensation on the rotating shaft of the spark machine body using the eccentricity compensation method for the spark machine rotating shaft according to any one of claims 1 to 8.

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