Electrical discharge machine tool and machining method

Abstract

The invention relates to the technical field of numerical control machine tools, in particular to an electric discharge machining tool and a machining method. The stand column is fixed to the base; the X-axis moving platform is connected to the base and can move along the X axis relative to the base; the Y-axis moving platform is connected to the X-axis moving platform and can move along the Y axis relative to the X-axis moving platform, and the Y-axis moving platform is provided with a cutter and a workpiece station; the Z-axis moving assembly is connected to the stand column and can move along the Z axis relative to the stand column; the rotary electrode is connected to the lower end of the Z-axis moving assembly and can rotate around the Z axis relative to the Z-axis moving assembly; wherein during any two adjacent machining procedures, the Y-axis moving platform and the Z-axis moving assembly are actuated, and the rotary electrode rotates, so that the tool machines the rotary surface of the rotary electrode. Through the configuration, the rotary electrode is cut to ideal surface precision, and a feasible machining process is provided for machining an object which is difficult to mechanically cut.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of numerical control machine tools, in particular to a spark-erosion machine tool and a machining method. BACKGROUND

[0002] As a key component of rotary steering system and turbine drill, sliding bearing composed of polycrystalline diamond (PCD) has been monopolized by European and American enterprises for a long time. At present, the radial bearing used by domestic rotary steering system is mainly a hard alloy sliding bearing, and the thrust bearing is mainly a PCD bearing. Similarly, the cutting teeth of drill used in oil drilling mainly use PCD as the main material. However, if mechanical cutting is used to process PCD workpieces, it is easy to cause PCD to crack. Further, if the PCD workpiece has a complex profile, it is required to change the clamping posture of the PCD workpiece between processes, which makes it difficult to ensure the machining precision. Therefore, in China, the processing equipment capacity in this industry is insufficient, and the preparation of high-precision friction pairs on complex structure inner holes, conical surfaces, spherical surfaces and other feature surfaces encounters great challenges. The feature surface composed of PCD is difficult to process and has high cost, and the above factors jointly restrict the popularization of related products on a large scale. SUMMARY

[0003] The present application provides a spark-erosion machine tool and a machining method to solve the defect that there is no processing equipment suitable for PCD workpieces in the prior art, and to realize a numerical control machine tool capable of precisely machining PCD workpieces and its machining process.

[0004] According to a first aspect of the present application, the present application provides a spark-erosion machine tool, comprising: a base; a column fixed to the base; an X-axis moving platform connected to the base and movable along an X-axis relative to the base; a Y-axis moving platform connected to the X-axis moving platform and movable along a Y-axis relative to the X-axis moving platform, the Y-axis moving platform being provided with a tool and a workpiece station; a Z-axis moving assembly connected to the column and movable along a Z-axis relative to the column; a rotary electrode connected to a lower end of the Z-axis moving assembly and rotatable about the Z-axis relative to the Z-axis moving assembly; wherein during any two adjacent machining processes, the Y-axis moving platform and the Z-axis moving assembly are actuated, and the rotary electrode is rotated so that the tool machines a rotary surface of the rotary electrode.

[0005] According to the present application, a kind of discharge processing machine tool is provided, tool and workpiece station are separated from each other at preset distance on Y axis moving platform, when Z axis moving assembly moves downward along Z axis, Z axis moving assembly and rotary electrode avoid contact with workpiece station and / or workpiece.

[0006] According to the present application, a kind of discharge processing machine tool is provided, workpiece station is workpiece holder, workpiece station is rotatable relative to Y axis moving platform, and the virtual rotation axis of rotation is parallel to Z axis.

[0007] According to the present application, a kind of discharge processing machine tool is provided, Z axis moving assembly includes detection head arranged at its lower end, and the detection head detects the location of workpiece and the size of its machined surface.

[0008] According to the second aspect of the present application, the present application also provides a kind of processing method, which is realized by using the discharge processing machine tool according to the first aspect of the present application, and is characterized by comprising the following steps: actuate X axis moving platform and Y axis moving platform, so that workpiece moves to the preset position relative to rotary electrode; actuate Z axis moving assembly, so that rotary electrode and workpiece at least partially coincide on Z axis; actuate rotary electrode, so that rotary electrode rotates relative to workpiece and discharges to perform predetermined machining process on workpiece; between any two predetermined machining processes, actuate Y axis moving platform and Z axis moving assembly, so that tool moves to the vicinity of circumferential outer surface of rotary electrode, and actuate rotary electrode to rotate, so that tool processes rotary surface of rotary electrode.

[0009] According to the present application, a kind of processing method is provided, and the process that tool processes rotary surface of rotary electrode further comprises: cut rotary electrode by preset amount, and set compensation amount for the radius of rotary electrode before performing next predetermined machining process.

[0010] According to the present application, a kind of processing method is provided, and predetermined machining process includes rough machining process, intermediate machining process and finish machining process.

[0011] According to the present application, a kind of processing method is provided, and rough machining process and intermediate machining process include: actuate rotary electrode, so that rotary electrode rotates slightly more than one circle in first direction relative to workpiece and discharges at the same time; actuate rotary electrode, so that rotary electrode rotates slightly more than one circle in second direction relative to workpiece and discharges at the same time.

[0012] According to the present application, a kind of processing method is provided, and finish machining process includes: During the actuation of the rotary electrode to rotate and discharge, the actuation X-axis moving platform reciprocates along the X-axis.

[0013] According to the processing method provided by the application, further comprising: Detecting the size of the processed surface by the detection head; In response to the detected size not reaching the preset threshold, repeatedly performing the previous predetermined processing procedure.

[0014] The EDM machine tool provided by the application processes the rotary electrode between any two predetermined processing procedures, especially processes the rotary electrode to the ideal size accuracy by using the cutting process, so that the feature surface composed of PCD is processed to the preset size accuracy during the EDM of the workpiece by the rotary electrode in the next predetermined processing procedure, which on the one hand saves the time, workload and cost of replacing the electrode between any two predetermined processing procedures, and on the other hand provides a feasible processing process for processing PCD workpieces and other objects that are difficult to be mechanically cut. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative labor.

[0016] Figure 1 It is a perspective view of the EDM machine tool provided by the application.

[0017] Reference signs: 1, base; 2, column; 3, X-axis moving platform; 4, Y-axis moving platform; 5, Z-axis moving assembly; 6, rotary electrode; 7, workpiece station; 8, tool; 9, X-axis motor; 10, Y-axis motor; 11, Z-axis track; 12, rotary motor; 13, detection head; 14, lubricating device. DETAILED DESCRIPTION

[0018] The embodiments of the application will be further described in detail below in combination with the drawings and examples. The following examples are used to illustrate the application, but cannot be used to limit the scope of the application.

[0019] In the description of the embodiments of the present application, it should be noted that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the embodiments of the present application. In addition, the terms "first", "second", "third" are only for the purpose of description and cannot be understood as indicating or implying relative importance.

[0020] In the description of the embodiments of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "connected", "connected" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, wherein the fixedly connected can include the way of integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium. For those skilled in the art, the specific meaning of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0021] In the embodiments of the present application, unless otherwise explicitly specified and limited, the first feature is "on" or "under" the second feature can be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature "above", "above" and "above" the second feature can be that the first feature is directly above or obliquely above the second feature, or only indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature "below", "below" and "below" the second feature can be that the first feature is directly below or obliquely below the second feature, or only indicates that the horizontal height of the first feature is less than that of the second feature.

[0022] In the description of the present application, the description of the terms "one embodiment", "some embodiments", "example", "specific example" or "some examples" means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present application, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine the different embodiments or examples described in the present application and the features of the different embodiments or examples without contradiction.

[0023] The discharge machining machine tool and machining method of the present application will be described below in conjunction with Figure 1 The discharge machining machine tool and machining method of the present application will be described below in conjunction with

[0024] Figure 1 is a perspective view of the electrical discharge machining machine provided by the present application, as Figure 1 As shown, the electrical discharge machining machine comprises a base 1, a column 2, an X-axis moving platform 3, a Y-axis moving platform 4, a Z-axis moving assembly 5 and a rotating electrode 6. The base 1 is laid on the ground, and the column 2 is fixedly connected to the base 1 or integrally formed with the base 1. The X-axis moving platform 3 is movably connected to the base 1, and can only move in a single dimension relative to the base 1, i.e. linearly move along the X-axis direction. The Y-axis moving platform 4 is movably mounted to the X-axis moving platform 3, and can only move in a single dimension relative to the X-axis moving platform 3, i.e. linearly move along the Y-axis direction. The Z-axis moving assembly 5 is movably connected to the column 2, and can only move in a single dimension relative to the column 2, i.e. linearly move along the Z-axis direction. The rotating electrode 6 is rotatably connected to the lower end of the Z-axis moving assembly 5, and can only move in a single dimension relative to the Z-axis moving assembly 5, i.e. rotatably move around the Z-axis.

[0025] Further, the Y-axis moving platform 4 can either be configured as a worktable itself, or have a worktable integrated thereon. The Y-axis moving platform 4 serving as a worktable is provided with a tool 8 and a workpiece station 7. The tool 8 and the workpiece station 7 are spaced apart from each other by a preset distance on the Y-axis moving platform 4, so that when the rotating electrode 6 needs to be machined by the tool 8, the Z-axis moving assembly 5 and the rotating electrode 6 descending along the Z-axis direction will not interfere with the workpiece station 7 and the workpiece possibly clamped thereon. Preferably, the workpiece station 7 is arranged near the center of the Y-axis moving platform 4, while the tool 8 is arranged at the edge of the Y-axis moving platform 4.

[0026] When a workpiece clamped in the workpiece station 7 is being electrically discharged, the X-axis moving platform 3 and the Y-axis moving platform 4 are actuated until the workpiece is moved to a preset position relative to the rotating electrode 6. In particular, when the surface to be machined is the circumferential outer surface of the workpiece, the preset position can be defined as that the distance between the virtual central axis of the workpiece and the projection of the Z-axis on the horizontal plane is slightly greater than the sum of the radius of the workpiece and the radius of the rotating electrode 6, and the projections of the two on the horizontal plane are collinear in the X-axis or Y-axis direction. While when the surface to be machined is the circumferential inner surface of the workpiece, the preset position can be defined as that the virtual central axis of the workpiece is coaxial with the Z-axis.

[0027] In contrast, when in the intermittent period between two predetermined machining processes, the rotating electrode 6 needs to be machined to a certain size accuracy level. The Y-axis moving platform 4 and the Z-axis moving assembly 5 are actuated until the tool 8 moves close to the circumferential outer surface of the rotating electrode 6. Then, the rotating electrode 6 is actuated to rotate, and the moving speed of the Y-axis moving platform 4 and the Z-axis moving assembly 5 are lowered respectively, so that the tool 8 machines the rotating surface of the rotating electrode 6. The advantage of this configuration is that, compared with the prior art which needs to replace the electrode of corresponding shape in response to the different machined surface profiles of the workpiece, the EDM machine tool of the present application does not need to replace the electrode, but instead performs the cutting machining process on the rotating electrode 6 by means of the automated cutting program, so that the rotating electrode 6 reaches the shape and the required size accuracy that matches the machined surface, so that the rotating electrode 6 participates in the subsequent next predetermined machining process.

[0028] Further, the X-axis moving platform 3 is movably connected to the base 1 by a screw and block mechanism. Specifically, the base 1 is provided with an X-axis motor 9 and an X-axis screw (not shown in the figure), the output shaft of the X-axis motor 9 is connected to the X-axis screw to drive the X-axis screw to rotate. The base 1 is also provided with an X-axis rail (not shown in the figure), and the X-axis moving platform 3 is slidingly connected to the X-axis rail. A specific position of the X-axis moving platform 3 is provided with a block (not shown in the figure), which is provided with a screw hole, and the X-axis screw is matched with the screw hole. Thus, the screw and block mechanism drives the X-axis moving platform 3 to move linearly along the X-axis rail.

[0029] Similarly, the Y-axis moving platform 4 is movably connected to the X-axis moving platform 3 by a screw and block mechanism. The X-axis moving platform 3 is provided with a Y-axis motor 10, a Y-axis screw (not shown in the figure), and a Y-axis rail (not shown in the figure), the output shaft of the Y-axis motor 10 is connected to the Y-axis screw, and the Y-axis moving platform 4 is slidingly connected to the Y-axis rail. A specific position of the Y-axis moving platform 4 is provided with a block (not shown in the figure), which is provided with a screw hole, and the Y-axis screw is matched with the screw hole. Thus, the screw and block mechanism drives the Y-axis moving platform 4 to move linearly along the Y-axis rail.

[0030] Similarly, the Z-axis moving assembly 5 is movably connected to the column 2 by a screw and block mechanism. The column 2 is provided with a Z-axis motor (not shown in the figure), a Z-axis screw (not shown in the figure), and a Z-axis rail 11, the output shaft of the Z-axis motor is connected to the Z-axis screw, and the Z-axis moving assembly 5 is slidingly connected to the Z-axis rail 11. A specific position of the Z-axis moving assembly 5 is provided with a block (not shown in the figure), which is provided with a screw hole, and the Z-axis screw is matched with the screw hole. Thus, the screw and block mechanism drives the Z-axis moving assembly 5 to move linearly along the Z-axis rail 11.

[0031] The rotating movement of the rotating electrode 6 relative to the Z-axis moving assembly 5 is driven by a rotary motor 12. The rotary motor 12 can be arranged at the upper end of the Z-axis moving assembly 5 and connected to the rotating electrode 6 through a rotary shaft (not shown in the figure) to drive the rotating movement of the rotating electrode 6 located at the lower end of the Z-axis moving assembly 5.

[0032] Further, the workpiece station 7 is a workpiece holder to hold the rotating workpiece thereon. Preferably, the workpiece station 7 can be arranged rotatable relative to the Y-axis moving platform 4 and the virtual rotation axis of the rotating movement thereof is parallel to the Z-axis. When the rotating electrode 6 performs the electrical discharge machining on the workpiece, the workpiece station 7 can rotate in the opposite direction of the rotating direction of the rotating electrode 6.

[0033] Further, the Z-axis moving assembly 5 further comprises a detection head 13 arranged at the lower end thereof. The detection head 13 detects the position of the workpiece and the size of the machined surface thereof. When setting the numerical control machining program of the electrical discharge machining machine tool, the detected position of the workpiece can be used to set the zero point and facilitate the definition of the subsequent X-axis, Y-axis and Z-axis feed amounts. After each execution of the electrical discharge machining process on the workpiece, the size accuracy of the machined surface can be detected in real time to determine whether the previous predetermined machining process has machined the workpiece to the preset threshold size, so as to determine whether the next process should be to repeat the previous predetermined machining process or to perform the next predetermined machining process according to the predetermined process flow.

[0034] Further, the electrical discharge machining machine tool further comprises a lubricating device 14. The lubricating device 14 can be arranged on the column 2. The interior of the electrical discharge machining machine tool further comprises a lubricating pipeline (not shown in the figure) to deliver the lubricating oil / grease injected from the lubricating device 14 to the corresponding moving mechanisms, i.e., the X-axis moving platform 3, the Y-axis moving platform 4, the Z-axis moving assembly 5, the rotating electrode 6 and the workpiece station 7.

[0035] The present application further provides a machining method which utilizes the above-mentioned electrical discharge machining machine tool to machine objects which are difficult to be machined by mechanical machining methods, such as PCD workpieces. The machining method comprises the following steps: S1 - actuate the X-axis moving platform 3 and the Y-axis moving platform 4 so that the workpiece moves to a preset position relative to the rotating electrode 6.

[0036] The X-axis moving platform 3 and the Y-axis moving platform 4 are simultaneously actuated, and the workpiece can be moved to any position in the horizontal plane. In the case that the machined surface can be the circumferential inner surface or the circumferential outer surface of the workpiece, the workpiece is moved to the corresponding preset position, i.e., the distance between the virtual central axis of the workpiece and the projection of the Z-axis on the horizontal plane is slightly greater than the sum of the radius of the workpiece and the radius of the rotating electrode 6, or the virtual central axis of the workpiece is coaxial with the Z-axis.

[0037] S2 - Actuate the Z-axis moving assembly 5 so that the rotating electrode 6 at least partially coincides with the workpiece in the Z-axis.

[0038] Actuate the Z-axis moving assembly 5 so that the Z-axis moving assembly 5 is lowered to a predetermined height. At this time, in the Z-axis direction, a partial axial section of the rotating electrode 6 coincides with a partial axial section of the workpiece, i.e., a partial circumferential outer surface of the rotating electrode 6 faces the machined surface of the workpiece (i.e., its circumferential inner surface or circumferential outer surface).

[0039] S3 - Actuate the rotating electrode 6 so that it rotates relative to the workpiece and discharges electricity to perform a predetermined machining process on the workpiece.

[0040] Actuate the rotating electrode 6 to rotate and supply electricity to the rotating electrode 6 to discharge electricity to the workpiece. The machining of PCD material itself is quite difficult, which to some extent limits its wider application. The EDM technology provides new possibilities for the machining of PCD material with its non-contact machining characteristics. Through the machining of the PCD workpiece by the rotating electrode 6, the processed PCD product finished product reaches a sufficient level of dimensional accuracy to be delivered for use.

[0041] S4 - Between any two predetermined machining processes, actuate the Y-axis moving platform and the Z-axis moving assembly so that the tool moves to the vicinity of the circumferential outer surface of the rotating electrode, and actuate the rotating electrode to rotate so that the tool machines the rotating surface of the rotating electrode.

[0042] When in the interval between the two preceding machining processes, the rotating electrode 6 needs to be machined to a specific level of dimensional accuracy. First, actuate the Y-axis moving platform 4 and the Z-axis moving assembly 5 simultaneously until the tool 8 moves to the vicinity of the circumferential outer surface of the rotating electrode 6, but does not contact the rotating electrode 6. Then, actuate the rotating electrode 6 to rotate and lower the moving speed of the Y-axis moving platform 4 and the Z-axis moving assembly 5 respectively so that the tool 8 processes (i.e., machines) the rotating surface of the rotating electrode 6 in sections. During this period, the tool 8 not only processes the dimensional accuracy of the rotating electrode 6 to reach the preset threshold, but also machines the rotating electrode 6 into a shape that matches the machined surface.

[0043] Wherein, in order to precisely machine the workpiece, accurately setting the zero point before starting to machine the workpiece is a very important basic step. For this purpose, it is necessary to calculate the offset of the virtual central axis of the workpiece relative to the Z-axis (i.e., equivalent to the virtual rotation axis of the rotating electrode 6). The offset can be calculated in the following way: Wherein, represents the offset in the X-axis direction, an X-axis coordinate position of the workpiece which comes into contact with the rotary electrode 6 in the positive direction in the X-axis direction, an X-axis coordinate position of the workpiece which comes into contact with the rotary electrode 6 in the negative direction in the X-axis direction, an offset amount in the Y-axis direction, a Y-axis coordinate position of the workpiece which comes into contact with the rotary electrode 6 in the positive direction in the Y-axis direction, a Y-axis coordinate position of the workpiece which comes into contact with the rotary electrode 6 in the negative direction in the Y-axis direction, a radius of the rotary electrode 6.

[0044] For some workpieces, the predetermined machining process can include a rough machining process and a finish machining process, and for other workpieces, the predetermined machining process can include a rough machining process, an intermediate machining process, and a finish machining process.

[0045] During the interval between the rough machining process and the finish machining process, the interval between the rough machining process and the intermediate machining process, and the interval between the intermediate machining process and the finish machining process, the above step S4 can further include: S41 - cutting the rotary electrode 6 by a preset amount, and setting a compensation amount for the radius of the rotary electrode 6 before performing the next predetermined machining process.

[0046] Preferably, the preset amount of cutting the rotary electrode 6 each time is set to 0.02mm-0.2mm. Moreover, a compensation amount for the radius of the rotary electrode 6 is set to the electrical discharge machining machine tool before performing the next predetermined machining process. The compensation amount is dynamically set based on parameters such as the cutting force of the tool 8, the electrical discharge gap between the rotary electrode 6 and the workpiece, etc.

[0047] More preferably, the Z-axis movement assembly 5 has different Z-axis feed amounts during different machining processes, which is defined as the distance from the top end of the workpiece to the bottom end of the rotary electrode 6 in the Z-axis direction. In the rough machining process, the first Z-axis feed amount of the Z-axis movement assembly 5 can be set to N, for example, 0.28 mm; in the intermediate machining process, the second Z-axis feed amount of the Z-axis movement assembly 5 can be set to N+0.01 mm~N+0.05 mm; and in the finishing machining process, the third Z-axis feed amount of the Z-axis movement assembly 5 can be set to N+0.01 mm~N+0.05 mm. Thus, between any two predetermined machining processes, the Z-axis feed amount of the next predetermined machining process is always slightly greater than that of the previous predetermined machining process, i.e., the third Z-axis feed amount > the second Z-axis feed amount > the first Z-axis feed amount. For the next predetermined machining process, the machined surface that has been machined by the previous predetermined machining process and the surface that has not been machined will be machined by the rotary electrode 6 of the next predetermined machining process, which can avoid collision between the rotary electrode 6 and the workpiece.

[0048] Similarly, during different machining processes, the above step S1 can further include the following steps in addition to moving the workpiece to the preset position (in particular, zero point) relative to the rotary electrode 6: actuating the X-axis movement platform 3 to provide an X-axis feed amount (hereinafter referred to as “X-axis feed amount”). In particular, in the rough machining process, the first X-axis feed amount of the X-axis movement platform 3 can be set to M, for example, 0.65 mm; in the intermediate machining process, the second X-axis feed amount of the X-axis movement platform 3 can be set to M+0.01 mm~M+0.05 mm; and in the finishing machining process, the third X-axis feed amount of the X-axis movement platform 3 can be set to M+0.01 mm~M+0.05 mm.

[0049] Further, for the above step S3, in particular, in the rough machining process and the intermediate machining process, the machining method further includes: S31 - actuating the rotary electrode 6 so that the rotary electrode 6 rotates relative to the workpiece in the first direction slightly more than one circle and discharges at the same time; S32 - actuating the rotary electrode 6 so that the rotary electrode 6 rotates relative to the workpiece in the second direction slightly more than one circle and discharges at the same time.

[0050] For example, the first direction is clockwise, and the second direction is counterclockwise, or vice versa. Moreover, the rotation range of the rotary electrode 6 is slightly larger than one circle, for example, the rotation angle is 370°, whether it is rotated in the first direction or in the second direction. The rotary electrode 6 rotates an extra 10° after one circle, which has no effect on the machined surface of the workpiece, in other words, the 10° rotation angle is essentially equivalent to the idle rotation of the rotary electrode 6, and such action is only to ensure that the entire machined (circumferential) surface of the workpiece is indeed processed. In the rough machining process and the intermediate machining process, the rotary electrode 6 is first rotated in the first direction to discharge the workpiece, and then rotated in the second direction to discharge, such processing can refine the machined surface and correct the texture defects left by the rough / intermediate machining process, for example, the stripes generated by one-way rotation and discharge.

[0051] Further, for the above step S3, especially in the finishing machining process, the machining method further comprises: S33 - actuating the X-axis moving platform 3 to reciprocate along the X-axis during the actuation of the rotary electrode 6 to rotate and discharge.

[0052] Considering that the successive discharge machining of the workpiece will cause inconsistent wear of the rotary surface of the rotary electrode 6, and the etchings generated by the electro-etching cannot be easily discharged from the discharge gap between the workpiece and the rotary electrode 6, in the finishing machining process, in addition to continuously actuating the Z-axis moving assembly 5 to slowly feed downward and actuating the rotary electrode 6 to rotate, the X-axis moving platform 3 can also be actuated to reciprocate along the X-axis. The reciprocation of the X-axis moving platform 3 can facilitate the discharge of the etchings in the discharge gap, and help to reduce the wear of the rotary electrode 6 during the discharge machining, for example, reduce the wear by 40% compared to the case where the X-axis moving platform 3 is stationary.

[0053] Further, the machining method further comprises: S51 - detecting the size of the machined surface using the detection head 13; S52 - in response to the detected size not reaching the preset threshold, repeating the previous predetermined machining process.

[0054] After each of the predetermined machining processes is performed, the size accuracy of the machined surface can be detected by the detection head 13. After the rough machining process, the surface accuracy of the machined surface is detected to see if it reaches a first preset threshold of the geometric tolerance; after the intermediate machining process, the surface accuracy of the machined surface is detected to see if it reaches a second preset threshold of the geometric tolerance; and after the finish machining process, the surface accuracy of the machined surface is detected to see if it reaches a third preset threshold of the geometric tolerance. If the surface accuracy reaches the first preset threshold, it means that after the intermittent period, the next predetermined machining process, i.e. the intermediate machining process, can be performed, and so on; otherwise, if the surface accuracy does not reach the first preset threshold, it means that after the intermittent period, the previous predetermined machining process, i.e. the rough machining process, needs to be repeated, and so on. Such process step planning ensures that the machined surface of the workpiece is indeed machined to the required size.

[0055] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than limit it; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that the technical solutions recorded in the foregoing embodiments can still be modified, or some technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. An electro-discharge machine tool, characterized by Comprising: a base (1); a column (2) fixed to the base (1); an X-axis moving platform (3) connected to the base (1) and movable along an X-axis relative to the base (1); a Y-axis moving platform (4) connected to the X-axis moving platform (3) and movable along a Y-axis relative to the X-axis moving platform (3), the Y-axis moving platform (4) being provided with a tool (8) and a workpiece station (7); a Z-axis moving assembly (5) connected to the column (2) and movable along a Z-axis relative to the column (2); a rotary electrode (6) connected to a lower end of the Z-axis moving assembly (5) and rotatable about the Z-axis relative to the Z-axis moving assembly (5); wherein during any two adjacent machining processes, the Y-axis moving platform (4) and the Z-axis moving assembly (5) are actuated, and the rotary electrode (6) is rotated, so that the tool (8) machines a rotary surface of the rotary electrode (6).

2. The electro-discharge machine according to claim 1, characterized by The tool (8) and the workpiece station (7) are separated from each other by a preset distance on the Y-axis moving platform (4), and when the Z-axis moving assembly (5) moves downward along the Z-axis, the Z-axis moving assembly (5) and the rotary electrode (6) avoid contact with the workpiece station (7) and / or a workpiece.

3. The electro-discharge machine according to claim 1, characterized by The workpiece station (7) is a workpiece holder, and the workpiece station (7) is rotatable relative to the Y-axis moving platform (4), and a virtual rotation axis of the rotation is parallel to the Z-axis.

4. The electro-discharge machine according to claim 1, characterized by The Z-axis moving assembly (5) comprises a detection head (13) arranged at a lower end thereof, and the detection head (13) detects a position of a workpiece and a size of a machined surface thereof.

5. A processing method which is implemented using the electrical discharge machine tool according to any one of claims 1 to 4, characterized by, Comprising the following steps: actuating the X-axis moving platform (3) and the Y-axis moving platform (4) so that a workpiece moves to a preset position relative to the rotary electrode (6); actuating the Z-axis moving assembly (5) so that the rotary electrode (6) at least partially coincides with a workpiece in the Z-axis; actuating the rotary electrode (6) so that the rotary electrode (6) rotates relative to the workpiece and discharges to perform a predetermined machining process on the workpiece; between any two of the predetermined machining processes, actuating the Y-axis moving platform (4) and the Z-axis moving assembly (5) so that the tool (8) moves to a vicinity of a circumferential outer surface of the rotary electrode (6), and actuating the rotary electrode (6) to rotate so that the tool (8) machines a rotary surface of the rotary electrode (6).

6. The method of claim 5, wherein, The machining process of the tool (8) on the rotary surface of the rotary electrode (6) further comprises: cutting a preset amount from the rotary electrode (6), and setting a compensation amount for a radius of the rotary electrode (6) before performing a next one of the predetermined machining processes.

7. The method of claim 5, wherein The predetermined machining processes comprise a rough machining process, an intermediate machining process, and a fine machining process.

8. The method of claim 7, wherein, The rough machining process and the intermediate machining process comprise: actuating the rotary electrode (6) so that the rotary electrode (6) rotates relative to the workpiece by slightly more than one circle in a first direction and discharges at the same time; The rotating electrode (6) is actuated so that the rotating electrode (6) rotates relative to the workpiece in the second direction by slightly more than one turn and discharges electricity at the same time.

9. The method of claim 7, wherein, The finishing process comprises: During the actuation of the rotating electrode (6) to rotate and discharge electricity, the X-axis moving platform (3) is actuated to reciprocate along the X-axis.

10. The method of claim 5, wherein, Further comprising: The detection head (13) is used to detect the size of the machined surface. In response to the detected size not reaching a preset threshold, the last said predetermined machining process is repeatedly executed.

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