A machining tool path control method

Abstract

The present application provides a machining tool path control method, including: obtaining a 3D model; extracting a curve of the final profile in the 3D model as a driving curve; obtaining the feed direction of the tool as a guide curve; determining the initial path curve of the tool according to the driving curve, the guide curve, and the initial profile; generating a universal direction with the driving curve as a generatrix point; obtaining a unique direction set and a feed amount selected in the universal direction; determining the machining end curve of the tool; using the machining end curve as a new initial path curve, repeating the steps of determining the machining end curve of the tool according to the initial path curve, the unique direction set, and the feed amount until the driving curve coincides with the machining end curve; combining all initial path curves into a continuous tool path curve, and controlling the tool to move according to the tool path curve. The present application can improve the surface finish of the special-shaped surface after machining.

Description

Technical Field

[0001] The present application belongs to the field of machine tool control, and specifically relates to a machining tool path control method. Background Art

[0002] When the machine tool performs machining such as cutting or milling on the object to be processed, and the final surface after processing is a special-shaped complex curved surface, due to the characteristics of the final surface with tortuous gradients and uncertain arc angle dimension values, the machine tool needs to repeatedly feed and retract the tool, and the tool path overlaps and covers, resulting in indentations during processing, the surface finish does not meet the standards, and the product qualification rate is not high. In addition, due to the need for multiple feeds and retracts, the final product will have poor product consistency due to error enrichment, long machining time, and high costs. Summary of the invention

[0003] An object of an embodiment of the present application is to provide a machining tool path control method.

[0004] According to an embodiment of the present application, a machining tool path control method is provided, comprising:

[0005] Acquire a 3D model, wherein the 3D model includes an initial profile of the object to be processed and a final profile after processing;

[0006] Extracting a curve of the final profile in the 3D model as a driving curve;

[0007] Get the cutting direction of the tool as the guide curve;

[0008] Determining an initial path curve of a tool according to the driving curve, the guide curve and the initial profile;

[0009] Generating a universal direction with the driving curve as a generatrix point on the initial path curve;

[0010] Obtaining a unique direction set and a cutting amount selected from the universal direction;

[0011] Determine a machining end curve of a tool according to the initial path curve, the unique direction set and the feed amount;

[0012] The processing end curve is used as a new initial path curve, and the step of determining the processing end curve of the tool according to the initial path curve, the unique direction set and the feed amount is repeated until the driving curve coincides with the processing end curve;

[0013] All the initial path curves are combined into a continuous tool path curve, and the tool is controlled to move according to the tool path curve to machine the object to be machined.

[0014] Optionally, the guiding curve is a curve intersecting with the driving curve.

[0015] Optionally, the guiding curve is a curve parallel to the driving curve.

[0016] Optionally, the method further includes: acquiring a step distance of the tool, and forming a path curve chain of the tool according to the step distance of the tool and the initial path curve.

[0017] Optionally, a path curve surface of the tool is constructed according to the step size of the tool and the initial path curve.

[0018] Optionally, the path curve is displayed on a display.

[0019] Optionally, the movement process of the tool along the path curve is displayed on a display.

[0020] Optionally, the driving curve is a closed curve.

[0021] Optionally, the initial path curve of the tool is a continuous curve.

[0022] Optionally, combining all the initial path curves into a continuous tool path curve, and controlling the tool to move according to the tool path curve to machine the object to be machined, comprises:

[0023] The continuous tool path curve is encoded, and the computer numerical control machine tool controls the tool movement according to the encoding to machine the object to be machined.

[0024] A technical effect of this application is:

[0025] The initial path curve of the tool is determined by the driving curve and the guide curve, and then the feed is started according to the unique direction set. The machining end curve formed by the first machining is used as the initial path curve of the new tool, and the driving curve is gradually approached until the machining end curve coincides with the driving curve. Finally, the tool is controlled to perform machining according to the continuous tool path curve formed by the initial path curve. The entire machining tool path only requires one feed and retract, avoiding indentations caused by repeated feed and retract, improving product qualification rate, improving product consistency, and reducing processing time and cost.

[0026] Other features and advantages of the present application will become apparent from the following detailed description of exemplary embodiments of the present application with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the application and, together with the description, serve to explain the principles of the application.

[0028] Figure 1 A machining principle diagram of a 3D model provided for one embodiment of the present application;

[0029] Figure 2 A schematic diagram of a driving curve and a guiding curve provided for one embodiment of the present application;

[0030] Figure 3 A schematic diagram of an initial path curve, a processing end curve, and a driving curve of a tool provided in one embodiment of the present application;

[0031] Figure 4 A schematic diagram of a continuous tool path curve provided for one embodiment of the present application;

[0032] Figure 5 A flow chart of a machining tool path control method provided by one embodiment of the present application;

[0033] Figure 6 A flowchart of a machining tool path control method provided by another embodiment of the present application.

[0034] in:

[0035] 1. Workbench; 2. Tool; 3. 3D model; 4. Final profile; 5. Initial path curve; 6. Retract path; 7. Feed path; 8. Drive curve; 9. Guide curve; 10. First processing end curve; 11. First direction; 12. Second direction; 13. Second processing end curve. DETAILED DESCRIPTION

[0036] Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that unless otherwise specifically stated, the relative arrangement of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present application.

[0037] The embodiments of the present application will be described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and should not be understood as limiting the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present application.

[0038] The term "first" or "second" in the specification and claims of this application may include one or more of the features explicitly or implicitly. In the description of this application, unless otherwise specified, "plurality" means two or more. In addition, "and / or" in the specification and claims means at least one of the connected objects, and the character " / " generally means that the objects connected before and after are in an "or" relationship.

[0039] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0040] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0041] It should be noted that like reference numerals and letters refer to similar items in the following figures, and therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0042] Reference Figures 1 to 5 The embodiment of the present application provides a machining tool path control method, which can be applied to a machine tool, which can use a tool 2 to perform milling, cutting and other mechanical processing on an object to be processed placed on a workbench 1. In the following description, the tool 2 is exemplarily a milling cutter. In other embodiments of the present application, the tool 2 can also be a cutter, a grinder, etc.

[0043] The machining tool path control method includes:

[0044] Step 101: Acquire a 3D model 3, wherein the 3D model 3 includes an initial profile of the object to be processed and a final profile 4 after processing;

[0045] Step 102: extracting a curve of the final profile 4 in the 3D model 3 as the driving curve 8;

[0046] Step 103: Obtain the feed direction of the tool 2 as the guide curve 9;

[0047] Step 104 determines the initial path curve 5 of the tool 2 according to the driving curve 8, the guiding curve 9 and the initial profile;

[0048] Step 105: generating a universal direction with the driving curve 8 as a generatrix point on the initial path curve 5;

[0049] Step 106: obtaining a unique direction set and a cutting amount selected from the universal direction;

[0050] Step 107: determining a machining end curve of a tool according to the initial path curve 5, the unique direction set and the feed amount;

[0051] Step 108: Determine whether the driving curve 8 coincides with the processing end curve;

[0052] Step 109: If the result of the judgment in step 108 is negative, the machining end curve is used as a new initial path curve, and the step of determining the machining end curve of the tool according to the initial path curve, the unique direction set and the feed amount is repeated until the drive curve 8 coincides with the machining end curve;

[0053] Step 110: All the initial path curves 5 are combined into a continuous tool path curve, and the tool 2 is controlled to move according to the tool path curve to machine the object to be machined.

[0054] In one embodiment of the present application, Figure 1 As shown, first, a 3D (3 Dimensions) model 3 needs to be constructed. This 3D model 3 includes the initial profile of the object to be processed and the final profile 4 after processing. Figure 1 In the figure, the material of the object to be processed has been partially milled away, showing the final profile 4, while in the actual 3D model 3, the initial profile of the object to be processed can also be constructed. The 3D model 3 can be constructed by CAM (Computer Aided Manufacturing) technology. During machining, the tool 2 will start machining the object to be processed along the feed path 7, and after the final profile 4 is machined, the tool 2 will retract along the retraction path 6. The movement path of the tool 2 can have components in the X direction, the Y direction, and the Z direction. At the beginning of machining, the tool 2 starts machining along the feed path 7, so a feed direction can be determined.

[0055] like Figure 1 , Figure 2As shown, a curve of the final profile 4 is extracted from the 3D model 3 as the driving curve 8. The final profile 4 can be regarded as a surface formed by countless lines. The final profile 4 is a special-shaped surface, that is, it is not a regular surface such as a cone or a sphere. A curve can be arbitrarily extracted between the upper and lower boundaries of the final profile 4 as the driving curve 8. Accordingly, the driving curve 8 is a space curve. The feed direction is a straight line, but in three-dimensional space we still regard it as a very short curve, and the feed direction is used as the guide curve 9.

[0056] like Figure 1 and Figure 2 As shown, after the driving curve 8 and the guiding curve 9 are determined, the two curves can determine a curved surface, and the curve intersecting the curved surface with the initial profile of the object to be processed determines the initial path curve 5 of the tool 2 during the first milling.

[0057] like Figure 3 As shown in FIG. 1 , after determining the initial path curve 5 and the driving curve 8, a universal direction with the driving curve 8 as the generatrix point can be generated on the initial path curve 5. That is, with the driving curve 8 as the path passed by the machining surface of the tool 2, the following can be generated on the initial path curve 5: Figure 3 In the case of multiple directions shown in FIG. 1 , it is necessary to manually select the direction in which the tool 2 moves. Assume that the computer user selects Figure 3 If the tool 2 moves in the first direction 11 and the tool 2 moves in the second direction 12, the computer can obtain the manually input parameters, thereby obtaining a unique direction set (including the first direction 11 and the second direction 12) from the universal direction. The computer also needs to obtain the feed amount input by the user.

[0058] like Figure 3 As shown in Figure 2, after obtaining the unique direction set and feed amount, the computer can determine a machining end curve for the tool. Figure 3 In the figure, the first acquired machining technology curve is marked as the first machining end curve 10. The maximum distance between the first machining end curve 10 and the initial path curve 5 is the feed amount. In addition, since the first machining end curve 10 is formed along the milling direction of the unique direction set based on the initial path curve 5, the first machining end curve 10 is also a directional curve.

[0059] like Figure 4As shown, after the first machining end curve 10 is generated, since the first machining end curve 10 does not coincide with the drive curve 8, it means that the first machining of the tool does not mill the required final profile 4. Therefore, the first machining end curve 10 is used as a new initial path curve, and the steps of determining the new machining end curve of the tool according to the initial path curve, the unique direction set and the feed amount are repeated. That is, the first machining end curve 10 is used as the new initial path curve, and the second machining end curve 13 is determined according to the unique direction set and the feed amount. If the second machining end curve 13 still does not coincide with the drive curve 8, the second machining end curve is used as the new initial path curve to determine the third machining end curve, and so on, and the feed is gradually made until the drive curve 8 coincides with the machining end curve. Finally, the initial path curve determined for the first time and the initial path curves determined in the middle (i.e., the first machining end curve, the second machining end curve, ... the last machining end curve that does not overlap with the drive curve 8) are combined into a continuous tool path curve through the guide curves between the initial path curves. This continuous tool path curve is the route that tool 2 needs to run for milling the object to be processed. This continuous tool path curve, plus the following Figure 1 The feed path 7 and the retract path 6 shown constitute a complete movement path of the tool 2 . The machine tool can control the movement of the tool 2 according to the tool path curve to machine the object to be processed and form a final profile 4 .

[0060] From the above description, it can be seen that in the embodiment of the present application, the initial path curve 5 of the tool 2 is determined by the driving curve 8 and the guide curve 9, and then the feed milling is started according to the unique direction set, and the first processing end curve 10 formed by the first machining is used as the initial path curve of the new tool, and then the second processing end curve 13 is determined, and so on, gradually approaching the driving curve 8 until the processing end curve coincides with the driving curve, and finally the tool 2 is controlled to perform machining according to the continuous tool path curve formed by the initial path curve. The entire machining tool path only requires one feed path 7 and retract path 6, which avoids the indentation caused by repeated feed and retract, improves the product qualification rate, improves product consistency, and reduces processing time and cost.

[0061] exist Figure 4 In the figure, the tool path curves are in the same plane, but in fact, since the final profile 4 is a special-shaped surface with a three-dimensional spatial shape, the actual continuous tool path curve is a spatial curve similar to a coil spring having components in the X direction, Y direction and Z direction in the three-dimensional space.

[0062] like Figure 2As shown, in one embodiment of the present application, the guide curve 9 is a curve intersecting with the drive curve 8, and in other embodiments of the present application, the guide curve 9 is a curve parallel to the drive curve 8. Preferably, the guide curve 9 intersects with the drive curve 8, which means that the direction of the first feed of the tool 2 intersects with the guide curve 9, and in the subsequent milling process, it is easier to make the milling center of the tool 2 always face the drive curve 8, thereby reducing the machining error.

[0063] In one embodiment of the present application, the final profile 4 is relatively small, and the processing width of the tool 2 in one pass is greater than or equal to the width of the final profile 4. At this time, the continuous tool path curve can be a curve that advances along the first direction 11 and extends along the second direction 12.

[0064] like Figure 6 As shown, in another embodiment of the present application, the machining tool path control method further includes:

[0065] Step 111: Get the step length of tool 2. Figure 6 In the step 107, the step of obtaining the step of the tool 2 is after the step 107 of determining the machining end curve, but in other embodiments of the present application, obtaining the step of the tool 2 can also be performed simultaneously with obtaining the unique direction set, that is, the computer user can input the step of the tool 2 and the unique direction set through the same interface. After obtaining the step of the tool 2, when the area of ​​the final profile 4 is very large, the tool path curves of each cutting can be connected into a tool path curve chain by setting the cutting distance of a single first step. When the final profile 4 has transition chamfers in multiple directions in space, the tool path curve chains of each cutting can be connected to form a tool path curve surface.

[0066] In one embodiment of the present application, after a continuous tool path curve, chain, or surface is formed, the path curve can be displayed on a display for adjustment by a computer user.

[0067] In one embodiment of the present application, after a continuous tool path curve, chain, or surface is formed, the movement process of the tool 2 along the path curve can be displayed on a display for adjustment by a computer user.

[0068] In one embodiment of the present application, Figures 2 to 4 As shown, the driving curve 8 is a closed curve, which enables each initial path curve to be directly constructed into a continuous curve, which is more efficient. In other embodiments of the present application, the driving curve 8 can also be an open curve, for example, there are gaps at certain positions, in which case the computer user needs to manually connect the disconnected parts to construct a continuous curve, which reduces efficiency.

[0069] In one embodiment of the present application, Figures 2 to 4As shown, the initial path curve 5 of the tool 2 is a continuous curve, so the subsequent processing end curve can also be a continuous curve, so that each initial path curve can also be directly constructed into a continuous curve, which is more efficient. In other embodiments of the present application, the initial path curve 5 of the tool 2 can also be a discontinuous curve, but in this case, the computer user needs to manually connect the disconnected parts, which reduces efficiency.

[0070] In one embodiment of the present application, all initial path curves are combined into a continuous tool path curve, and a tool is controlled to move according to the tool path curve to machine the object to be machined, including:

[0071] The continuous tool path curve is encoded, and the computer numerical control (Computer Numerical Control) machine tool controls the movement of the tool 2 according to the encoding to machine the object to be processed.

[0072] In some embodiments of the present application, the steps from constructing a 3D model to combining all the initial path curves into a continuous tool path curve can be implemented by computer software, and then the continuous tool path curve is encoded to generate a control code or a program decoding specified by an instruction, and the control code or the program decoding is transmitted to a computer numerical control machine tool. The computer numerical control machine tool then controls the motion trajectory of the tool 2 according to the control code or the program decoding to perform machining on the object to be processed.

[0073] According to some embodiments of the present application, a non-transitory computer-readable medium is also provided, in which instructions are stored. When the instructions are executed by one or more processors, the machining tool path control method as described above can be executed.

[0074] According to some embodiments of the present application, a computer numerically controlled machine tool is also provided, which includes the non-transitory computer readable medium, processor, and actuator as described above. When the instructions in the non-transitory computer readable medium are executed by one or more processors, the actuator can drive the tool 2 to move along a continuous tool path curve to machine the object to be processed and form a final surface 4.

[0075] Although some specific embodiments of the present application have been described in detail by way of example, it should be understood by those skilled in the art that the above examples are only for illustration, not for limiting the scope of the present application. It should be understood by those skilled in the art that the above embodiments may be modified without departing from the scope and spirit of the present application. The scope of the present application is defined by the appended claims.

Claims

1. A machining tool path control method, characterized in that: include: Acquire a 3D model, wherein the 3D model includes an initial profile of the object to be processed and a final profile after processing; Extracting a curve of the final profile in the 3D model as a driving curve; Get the cutting direction of the tool as the guide curve; Determining the initial path curve of the tool according to the driving curve, the guide curve and the initial profile, comprising: after determining the driving curve and the guide curve, being able to determine a surface, the curve of the surface intersecting with the initial profile of the object to be processed, determining the initial path curve of the tool; Generating a universal direction with the driving curve as a generatrix point on the initial path curve; Obtaining a unique direction set and a cutting amount selected from the universal direction; Determine a machining end curve of a tool according to the initial path curve, the unique direction set and the feed amount; The processing end curve is used as a new initial path curve, and the step of determining the processing end curve of the tool according to the initial path curve, the unique direction set and the feed amount is repeated until the driving curve coincides with the processing end curve; All the initial path curves are combined into a continuous tool path curve, and the tool is controlled to move according to the tool path curve to machine the object to be machined.

2. The machining tool path control method according to claim 1, characterized in that: The guide curve is a curve intersecting with the drive curve.

3. The machining tool path control method according to claim 1, characterized in that: The guide curve is a curve parallel to the driving curve.

4. The machining tool path control method according to claim 1, characterized in that: Also includes: The step length of the tool is obtained, and a tool path curve chain is formed according to the step length of the tool and the initial path curve.

5. The machining tool path control method according to claim 4, characterized in that: A tool path curve surface is formed according to the step distance of the tool and the initial path curve.

6. The machining tool path control method according to claim 1, characterized in that: The path curve is displayed on a display.

7. The machining tool path control method according to claim 6, characterized in that: The movement process of the tool along the path curve is displayed on the display.

8. The machining tool path control method according to claim 1, characterized in that: The driving curve is a closed curve.

9. The machining tool path control method according to claim 1, characterized in that: The initial path curve of the tool is a continuous curve.

10. The machining tool path control method according to claim 1, characterized in that: The step of combining all the initial path curves into a continuous tool path curve and controlling the tool to move according to the tool path curve to machine the object to be machined comprises: The continuous tool path curve is encoded, and the computer numerical control machine tool controls the tool movement according to the encoding to machine the object to be machined.

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