Automatic correction machining method for workpiece inclination and coordinate axis perpendicularity error

Abstract

The invention relates to the technical field of linear cutting intelligent machining, in particular to an automatic correction machining method for workpiece oblique placement and coordinate axis perpendicularity errors, which adopts a workpiece oblique placement compensation algorithm and a coordinate perpendicularity compensation algorithm, automatically calculates a compensated accurate position according to an error value, downloads the compensated accurate position to a controller, reads a real-time position during machining at the same time, and automatically corrects the workpiece oblique placement and coordinate axis perpendicularity errors. And inversely calculating a position matched with the processing graph for display. And meanwhile, single-axis button movement is added, single-axis movement of the manual pulse generator is utilized, compensation calculation can be participated, and consistency of coordinate display and manual and automatic functions is guaranteed. According to the scheme, the user operation difficulty is reduced through workpiece inclined placement compensation, and the machining precision of the machine tool is improved through machine tool coordinate value perpendicularity compensation.

Description

Technical Field

[0001] The present invention relates to the technical field of wire cutting intelligent processing, and in particular to a method for automatically correcting the errors of workpiece tilt and coordinate axis verticality. Background Art

[0002] The wire cutting system is a proprietary control system used in metal mold processing. It consists of a host computer software and a slave computer controller (a programmable logic controller (PLC), or a control card, etc.). The system controls the molybdenum wire (the molybdenum wire is guided through the workpiece through a wire guide or a guide wheel) to move along the imported mold graphic trajectory, thereby processing the mold workpiece. The workpiece placed on the actual machine tool must be consistent with the direction of the imported mold graphic to ensure the accuracy of the workpiece processing.

[0003] In the existing wire cutting system, during the actual processing, when the workpiece is manually placed on the machine tool, it is impossible to ensure that the 0° reference line of the workpiece being processed is parallel to the 0° reference line (X axis) of the machine tool (i.e. the processing pattern is consistent with the workpiece direction), and the workpiece position needs to be corrected by multiple auxiliary means such as knocking the workpiece and measuring sparks. This step wastes time and tests the operator's proficiency, which in turn affects the processing efficiency and processing accuracy.

[0004] In addition, during the installation process of existing wire cutting machines, due to objective factors such as manual calibration accuracy and installation tolerance, the X-axis and Y-axis of the machine tool coordinate axes may not be vertical. At the same time, the size of the molds that need to be processed by wire cutting machines is getting larger and larger, and there are more and more machines with large strokes. The non-vertical X-axis and Y-axis of the machine tool will affect the accuracy of the mold processing to a certain extent; at the same time, this error cannot be compensated manually.

[0005] Therefore, a new technical solution is urgently needed to solve the above technical problems. Summary of the invention

[0006] The purpose of the present invention is to overcome the above-mentioned problems of the prior art and to provide a method for automatically correcting the tilt of a workpiece and the verticality error of the coordinate axis, so as to solve the technical problems that the machine tool for manually placing the workpiece in the prior art cannot ensure that the processing pattern is consistent with the workpiece direction, and the existing wire cutting machine tool cannot ensure that the machine tool coordinate axes X and Y are completely vertical due to objective reasons of manual installation, thereby affecting the workpiece processing efficiency and accuracy.

[0007] The above objectives are achieved through the following technical solutions:

[0008] A method for automatically correcting workpiece tilt and coordinate axis verticality errors, including workpiece tilt compensation and machine tool coordinate value verticality compensation, wherein the workpiece tilt compensation comprises the following steps:

[0009] Step (1.1) measures a calibration point according to the actual position of the workpiece on the machine tool, calculates the deflection angle of the workpiece according to the calibration point as the workpiece coordinate deflection angle; and constructs a workpiece tilt compensation algorithm according to the workpiece coordinate deflection angle;

[0010] Step (1.2) The wire cutting system analyzes the points of the two-dimensional figure of the workpiece, calculates the compensated workpiece X-axis motion data and the workpiece Y-axis motion data according to the workpiece tilt compensation algorithm described in step (1.2), and sends the workpiece X-axis motion data and the workpiece Y-axis motion data to the controller;

[0011] In step (1.3), the wire cutting system obtains the real-time position fed back by the controller when the control axis moves, and obtains the coordinate position of the workpiece after it is aligned by the inverse operation of the workpiece tilt compensation algorithm;

[0012] The verticality compensation of the machine tool coordinate value comprises the following steps:

[0013] Step (2.1) obtains the verticality error angle of the machine tool by measurement, and constructs a machine tool verticality error compensation algorithm according to the verticality error angle of the machine tool;

[0014] Step (2.2) calculates the actual machine tool X-axis position and the actual machine tool Y-axis position data after compensation according to the machine tool verticality error compensation algorithm, and sends them to the controller;

[0015] In step (2.3), the wire cutting system obtains the real-time position of the machine tool fed back by the controller when the control axis moves, and obtains the coordinate position of the machine tool in the vertical state through the inverse operation of the machine tool verticality error compensation algorithm.

[0016] Furthermore, the step (1.1) is specifically as follows:

[0017] If two calibration points are set on one edge of the workpiece, including calibration point A and calibration point B, then there is a vector According to the vector Calculate the deflection angle of the workpiece, denoted as θ, that is, the deflection angle of the workpiece coordinates, then we have

[0018] The target position of the workpiece after rotation is recorded as (x', y'), then:

[0019] x'=x*cosθ+y*sinθ;

[0020] y'=y*cosθ+x*sinθ.

[0021] Furthermore, the step (1.1) is specifically as follows:

[0022] The coordinate system of the machine tool in the normal state is set to (x, y), the coordinate system of the actual machine tool is set to (x', y'), and the angle between y' and y is θ, which is the verticality error angle of the machine tool. Then:

[0023] x' = x;

[0024] y'=y*cosθ-x*sinθ.

[0025] Furthermore, the workpiece tilt compensation and the machine tool coordinate value verticality compensation are performed simultaneously, and the wire cutting system first performs the machine tool coordinate value verticality compensation and then performs the workpiece tilt compensation according to the compensation value.

[0026] The present invention provides an automatic correction processing method for workpiece tilt and coordinate axis verticality error, which adopts the method of measuring two calibration points to calculate the deflection angle of the workpiece, and directly compensates during processing without forcibly straightening the workpiece, thereby reducing the difficulty of user operation; through the verticality error obtained by measurement, the compensated position is automatically calculated according to the verticality error during the processing, and the error caused by mechanical installation can be corrected by software, thereby improving the accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a flow chart of a method for automatically correcting a workpiece tilt and coordinate axis verticality error according to the present invention;

[0028] Figure 2 It is a schematic diagram of a workpiece tilt compensation algorithm in a method for automatically correcting a workpiece tilt and coordinate axis verticality error according to the present invention;

[0029] Figure 3 The present invention is a schematic diagram of a machine tool coordinate axis verticality error compensation algorithm in a workpiece tilting and coordinate axis verticality error automatic correction processing method. DETAILED DESCRIPTION

[0030] The present invention is further described in detail below based on the accompanying drawings and embodiments. The described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] This solution provides an automatic correction method for workpiece tilt and coordinate axis verticality errors. For user convenience and to improve processing accuracy, in order to avoid errors caused by workpiece placement correction and non-vertical machine installation during processing, workpiece tilt compensation algorithm and coordinate verticality compensation algorithm are introduced respectively. According to the error value, the precise position after compensation is automatically calculated and downloaded to the controller. At the same time, the real-time position during processing is read, and the position matching the processing graphics is inversely calculated for display. At the same time, adding single-axis button movement and using manual pulse generator single-axis movement can all participate in the compensation calculation, thereby ensuring the consistency of coordinate display and manual automatic functions.

[0032] like Figure 1 As shown, this solution uses the wire cutting software to calculate the processing data generated by the workpiece graphics before sending it to the controller, and performs inverse compensation display on the real-time coordinate position fed back by the controller, while compensating and rotating the current processing graphics to achieve the best effect of positive processing of tilted workpieces; mainly including workpiece tilt compensation and machine tool coordinate value verticality compensation;

[0033] Wherein, the workpiece tilt compensation comprises the following steps:

[0034] Step (1.1) measures a calibration point according to the actual position of the workpiece on the machine tool, calculates the deflection angle of the workpiece according to the calibration point as the workpiece coordinate deflection angle; and constructs a workpiece tilt compensation algorithm according to the workpiece coordinate deflection angle;

[0035] Step (1.2) The wire cutting system analyzes the points of the two-dimensional figure of the workpiece, calculates the compensated workpiece X-axis motion data and the workpiece Y-axis motion data according to the workpiece tilt compensation algorithm described in step (1.2), and sends the workpiece X-axis motion data and the workpiece Y-axis motion data to the controller;

[0036] In step (1.3), the wire cutting system obtains the real-time position fed back by the controller when the control axis moves, and obtains the coordinate position of the workpiece after it is aligned through the inverse operation of the workpiece tilt compensation algorithm. Meanwhile, other auxiliary axis shifting functions of the system are involved in the calculation of the workpiece tilt compensation algorithm. When a manual pulse generator is used to specify single-axis movement, the generated single-axis pulses are calculated by the workpiece tilt compensation algorithm and split into two-axis interpolation movements to ensure the consistency of the coordinate system.

[0037] Wherein, the verticality compensation of the machine tool coordinate value comprises the following steps:

[0038] Step (2.1) obtains the verticality error angle of the machine tool by measurement, and constructs a machine tool verticality error compensation algorithm according to the verticality error angle of the machine tool;

[0039] Step (2.2) calculates the actual machine tool X-axis position and the actual machine tool Y-axis position data after compensation according to the machine tool verticality error compensation algorithm, and sends them to the controller;

[0040] In step (2.3), the wire cutting system obtains the real-time position of the machine tool fed back by the controller when the control axis moves, and obtains the coordinate position of the machine tool in the vertical state through the inverse operation of the machine tool verticality error compensation algorithm, which is convenient for corresponding to the processing graphics.

[0041] The above solution uses the workpiece tilt compensation algorithm and the coordinate axis verticality compensation algorithm to compensate for errors in the workpiece tilt and coordinate axis verticality, ensuring accurate execution of the processing position. At the same time, it optimizes the coordinate display and processing graphic display, allowing users to experience the compensation method more intuitively and improve the system's operational convenience.

[0042] The workpiece tilt compensation algorithm in step (1.1) of this embodiment is to deflect the coordinate system and then calculate the actual workpiece position, specifically:

[0043] like Figure 2 As shown, two calibration points are set on one edge of the workpiece, including calibration point A and calibration point B, then there is a vector According to the vector Calculate the deflection angle of the workpiece, denoted as θ, that is, the deflection angle of the workpiece coordinates, then we have

[0044] The target position of the workpiece after rotation is recorded as (x', y'), then:

[0045] x'=x*cosθ+y*sinθ;

[0046] y'=y*cosθ+x*sinθ.

[0047] The machine tool verticality error compensation algorithm in step (1.1) of this embodiment is a calculation that converts the position of the coordinate axis under verticality into the position of the coordinate axis under non-verticality, specifically:

[0048] like Figure 3 As shown, the coordinate system of the machine tool in the normal state is set to (x, y), the coordinate system of the actual machine tool is (x', y'), and the angle between y' and y is θ, which is the verticality error angle of the machine tool; the principle of machine tool verticality compensation is to convert the original coordinate value (x, y) into (x', y') according to the size of the verticality error; then:

[0049] x' = x;

[0050] y'=y*cosθ-x*sinθ.

[0051] In this solution, the workpiece tilt compensation and the machine tool coordinate value verticality compensation can be performed simultaneously. The wire cutting system first performs machine tool coordinate value verticality compensation according to the compensation value, and then performs workpiece tilt compensation, so that a simultaneous compensation effect can be achieved.

[0052] The above description is only for illustrating the implementation mode of the present invention and is not intended to limit the present invention. For those skilled in the art, any modification, equivalent substitution, improvement, etc. 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 automatically correcting the workpiece tilt and coordinate axis verticality error, characterized in that: It includes workpiece tilt compensation and machine tool coordinate value verticality compensation, and the workpiece tilt compensation includes the following steps: Step (1.1) measures a calibration point according to the actual position of the workpiece on the machine tool, calculates the deflection angle of the workpiece according to the calibration point as the workpiece coordinate deflection angle; and constructs a workpiece tilt compensation algorithm according to the workpiece coordinate deflection angle; Step (1.2) The wire cutting system analyzes the points of the two-dimensional figure of the workpiece, calculates the compensated workpiece X-axis motion data and the workpiece Y-axis motion data according to the workpiece tilt compensation algorithm described in step (1.2), and sends the workpiece X-axis motion data and the workpiece Y-axis motion data to the controller; In step (1.3), the wire cutting system obtains the real-time position fed back by the controller when the control axis moves, and obtains the coordinate position of the workpiece after it is aligned by the inverse operation of the workpiece tilt compensation algorithm; The verticality compensation of the machine tool coordinate value comprises the following steps: Step (2.1) obtains the verticality error angle of the machine tool by measurement, and constructs a machine tool verticality error compensation algorithm according to the verticality error angle of the machine tool; Step (2.2) calculates the actual machine tool X-axis position and the actual machine tool Y-axis position data after compensation according to the machine tool verticality error compensation algorithm, and sends them to the controller; In step (2.3), the wire cutting system obtains the real-time position of the machine tool fed back by the controller when the control axis moves, and obtains the coordinate position of the machine tool in the vertical state through the inverse operation of the machine tool verticality error compensation algorithm.

2. The method for automatically correcting the workpiece tilt and coordinate axis verticality error according to claim 1, characterized in that: The step (1.1) is specifically: If two calibration points are set on one edge of the workpiece, including calibration point A and calibration point B, then there is a vector According to the vector Calculate the deflection angle of the workpiece, denoted as θ, that is, the deflection angle of the workpiece coordinates, then we have The target position of the workpiece after rotation is recorded as (x', y'), then: x'=x*cosθ+t*sinθ; y'=y*cosθ+x*sinθ.

3. The method for automatically correcting the workpiece tilt and coordinate axis verticality error according to claim 1, characterized in that: The step (1.1) is specifically: The coordinate system of the machine tool in the normal state is set to (x, y), the coordinate system of the actual machine tool is set to (x', y'), and the angle between y' and y is θ, which is the verticality error angle of the machine tool. Then: x' = x; y'=y*cosθ-x*sinθ.

4. The method for automatically correcting the workpiece tilt and coordinate axis verticality error according to claim 1, characterized in that: The workpiece tilt compensation and the machine tool coordinate value verticality compensation are performed simultaneously. The wire cutting system first performs machine tool coordinate value verticality compensation and then performs workpiece tilt compensation according to the compensation value.

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