JP2005144620A - Shape processing method by numerical control processing machine, numerical control device, machine tool, nc program making device and nc program making program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform highly accurate shape processing by avoiding reduction in shape processing accuracy by radial directional deflection of a tool, in the shape processing using a ball end mill by an orthogonal triaxial machine tool. <P>SOLUTION: An NC program is analyzed with respective block data by using the NC program of describing normal vector information for indicating a normal vector of a processing surface in a contact point of the tool and a workpiece with respective block data including feed shaft position information. A deflection correction quantity of the tool corresponding to the normal vector of the processing surface, is calculated with respective analyzed block data. A feed shaft position is corrected in response to the calculated tool deflection correction quantity. The shape processing is performed in response to the corrected feed shaft position. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a shape processing method using a numerical control processing machine, a numerical control device, a machine tool, an NC program creation device, and an NC program creation program, and in particular, a shape such as a mold using an orthogonal three-axis numerical control processing machine. The present invention relates to a machining method for carrying out machining, a numerical control device for carrying out the shape machining method, a machine tool, an NC program creation device using a CAM device, etc., and an NC program creation program.

  There are numerical control devices and numerical control processing machines (machine tools) that perform shape processing including a free-form surface such as a die using a cutting tool such as a ball end mill (for example, Patent Document 1 and Patent Document 2).

  When shape machining is performed using a ball end mill or the like with a machine tool with three axes orthogonal to the X, Y, and Z axes, the tool axis is vertical and unchanged, while the machining surface is a curved surface (inclined surface). Therefore, it has an angle other than 90 degrees with respect to the tool axis.

For this reason, the normal vector of the machining surface at the contact point between the tool such as a ball end mill and the workpiece does not coincide with the tool axis, and a radial cutting load acts on the tool tip. For this reason, a deflection in the radial direction occurs in the tool, and the shape machining accuracy is lowered.
JP-A-9-29584 JP 2002-96243 A

  The problem to be solved by the present invention is that, in shape processing using a ball end mill or the like with an orthogonal three-axis machine tool, it is possible to avoid a decrease in shape processing accuracy due to radial deflection of the tool and perform high-precision shape processing. Is to do.

  The shape machining method according to the present invention is a machining method for performing shape machining using an orthogonal three-axis numerically controlled machining machine, and machining at a contact point between a tool and a workpiece for each block data including feed axis position information. An NC program in which normal vector information indicating the normal vector of the surface is described is used, the NC program is analyzed for each block data, and the normal vector of the machining surface is determined for each analyzed block data. The deflection correction amount of the tool is calculated, the feed axis position is corrected according to the calculated tool deflection correction amount, and the shape machining is performed according to the corrected feed axis position.

  The numerical control apparatus according to the present invention is a numerical control apparatus for an orthogonal three-axis machine tool, and shows a normal vector of a machining surface at a contact point between a tool and a workpiece for each block data including feed axis position information. An analysis unit that analyzes the NC program in which normal vector information is described for each block data, and a tool deflection correction according to the normal vector of the machining surface for each block data analyzed by the analysis unit A deflection correction amount calculation unit that calculates the amount, and a feed axis position correction unit that corrects the feed axis position according to the tool deflection correction amount calculated by the deflection correction amount calculation unit.

  The machine tool according to the present invention includes the numerical control device according to the above-described invention.

  An NC program creation device according to the present invention creates NC block data including feed axis position information from graphic data in an NC program creation device for creating an NC program of a numerical control device that performs shape machining using an orthogonal three-axis machine. NC block data creation unit for calculating, normal vector calculation unit for calculating the normal vector of the machining surface at the contact point between the tool and the workpiece for each block data from the graphic data, and calculation by the normal vector calculation unit Created by the NC block data creation unit according to the tool deflection correction amount calculated by the deflection correction amount calculation unit calculated by the deflection correction amount calculation unit calculated by the deflection correction amount of the tool according to the normal vector NC for output that corrects the feed axis position information of the NC block data that has been generated and creates NC block data for output And a lock data generating unit.

  An NC program creation program according to the present invention is a computer program for creating NC block data including feed axis position information from graphic data, and machining at a contact point between a tool and a workpiece for each NC block data from graphic data. A procedure for calculating a normal vector of a surface, a procedure for calculating a deflection correction amount of the tool according to the calculated normal vector, and a feed axis of the NC block data according to the calculated tool deflection correction amount This is an NC program creation program for executing a procedure for correcting position information and creating NC block data for output.

  An NC program creation device according to the present invention is a NC program creation device for creating an NC program for a numerical control device that performs shape machining using an orthogonal three-axis machine. A polyhedral approximation model creation unit that creates a polyhedron approximation model from graphic data A normal vector calculation unit that calculates a normal vector of each surface of the polyhedral approximate model, and tool deflection corresponding to the normal vector of each surface of the polyhedral approximate model calculated by the normal vector calculation unit A deflection correction amount calculation unit that calculates a correction amount, a correction polyhedron approximation model creation unit that creates a corrected polyhedron approximation model corrected according to the tool deflection correction amount calculated by the deflection correction amount calculation unit, and the correction polyhedron Each NC block data including feed axis position information from the corrected polyhedral approximate model created by the approximate model creation unit And a NC block data creation portion that formed.

  An NC program creation program according to the present invention includes a computer for creating a polyhedral approximate model from graphic data, a procedure for calculating a normal vector of each surface of the polyhedral approximate model, and each of the calculated polyhedral approximate model. From the procedure for calculating the tool deflection correction amount according to the normal vector of the surface, the procedure for creating the corrected polyhedral approximation model corrected according to the calculated tool deflection correction amount, and the created corrected polyhedral approximation model This is a program for creating each NC block data including feed axis position information and an NC program creating program for executing it.

  An NC program creation device according to the present invention is an NC program creation device for creating an NC program of a numerical control device that performs shape machining using an orthogonal three-axis machine, and a surface model creation unit that creates a surface model from graphic data; A normal vector calculation unit that calculates a normal vector of each surface of the surface model, and a tool deflection correction amount according to the normal vector of each surface of the surface model calculated by the normal vector calculation unit A deflection correction amount calculation unit, a correction surface model creation unit that creates a correction surface model corrected according to the tool deflection correction amount calculated by the deflection correction amount calculation unit, and a correction surface model creation unit. And an NC block data creation unit for creating NC block data including feed axis position information from the corrected surface model.

  An NC program creation program according to the present invention includes a computer for creating a surface model from graphic data, a procedure for calculating a normal vector of each surface of the surface model, and a method for calculating each surface of the surface model. The procedure for calculating the tool deflection correction amount according to the line vector, the procedure for creating the correction surface model corrected according to the calculated tool deflection correction amount, and the feed axis position information from the created correction surface model It is an NC program creation program for executing a procedure for creating NC block data.

  In these inventions, the amount of deflection correction is the normal vector of the machining surface for each NC block data, the normal vector of each surface of the polyhedral approximate model, or the normal vector of each surface of the surface model, and one block. Machining direction vector, feed speed, depth of cut, spindle speed, cutting method, tool type, tool material, tool length, tool protrusion length, tool diameter, at least one combination of workpiece materials, or more It can be calculated by a combination of pieces.

  According to the present invention, it is possible to perform shape machining by compensating for tool deflection in accordance with the normal vector of the machining surface, canceling reduction in shape machining accuracy due to radial deflection of the tool, and high-precision shape machining. It can be performed.

  One embodiment of an orthogonal three-axis numerically controlled processing machine and a numerical control device used to implement the shape processing method according to the present invention will be described with reference to FIGS. 1 and 2.

  The numerically controlled processing machine is a portal machine tool 10 having three orthogonal axes. The machine tool 10 includes a bed 11, a work table 12 provided on the bed 11 and movable in the Y-axis direction (horizontal direction penetrating the paper surface of FIG. 1 at right angles), and a pair of left and right provided on both sides of the bed 11. Columns 13, 14, a cross rail 15 spanning between the columns 13, 14 across the bed 11, and provided on the cross rail 15 and movable in the X-axis direction (horizontal direction in FIG. 1). It has a saddle 16 and a ram 17 provided on the saddle 16 and movable in the Z-axis direction (vertical direction in FIG. 1).

  A spindle head 18 including a spindle 18A is attached to the lower end of the ram 17. A tool 19 such as a ball end mill is replaceably mounted on a main shaft 18A of the main shaft head 18. A ram 17 is equipped with a spindle motor 20 that rotates the spindle 18A.

  The saddle 15 is axially fed in the X-axis direction by an X-axis feed screw 21 and an X-axis servomotor 22 that drives the X-axis feed screw 21. The work table 12 is axially fed in the Y-axis direction by a Y-axis feed screw (not shown) and a Y-axis servomotor 23 that drives the Y-axis feed screw. The ram 17 is axially fed in the Z-axis direction by a Z-axis feed screw 24 and a Z-axis servomotor 25 that drives the Z-axis feed screw 24.

  The rotation of the main shaft by the main shaft motor 20 and the respective axis feeds by the X-axis servo motor 22, the Y-axis servo motor 23, and the Z-axis servo motor 25 are controlled by the numerical controller 30.

  The numerical control device 30 is of a computer type and is hereinafter referred to as a CNC 30. The CNC 30 includes an analysis unit 31, a distribution unit 32, a feed axis command calculation unit 33, an actual speed calculation unit 34, a deflection correction amount calculation unit 35, a database 36, a feed axis command correction unit 37, and each feed. An X-axis control unit 38, a Y-axis control unit 39, a Z-axis control unit 40, and a machine control interface unit 41 that outputs a spindle rotation command to the spindle motor 20 are included.

The analysis unit 31 inputs an NC program from the CAM 50 and analyzes the NC program. The NC program has a control mode setting line based on a G code description that declares whether or not to perform deflection correction in the first line. For example, if G300, the deflection correction is cancelled, and the deflection correction is not performed. If G301, the deflection correction is performed when the deflection correction is on. In the case of G301, basic information necessary for deflection correction is described in the first line. This description is, for example,
G301, H, L, Q
H: Tool information (tool management number)
L: Machining information {Cutting method (scan line machining or contour machining), machining type
(Roughing or finishing)}
Q: Work material information (work material)
It is.

  The NC program has a plurality of block data in the first row and below. The block data, such as “G01 X, Y, Z, U, F, S”, respectively, is the feed axis position (X, Y, Z) and the contact point between the tool and the workpiece for each block data. The normal vector U indicating the normal vector of the machined surface, the feed speed F, and the spindle speed S are described.

  The normal vector U of the machining surface at the contact point A between the tool 19 and the workpiece W is directed from the contact point A between the tool 19 and the workpiece W to the tool center Tc, as shown in FIG. This is a vector indicating the direction, and is calculated from surface data of drawing data such as CAD in the CAM. The normal vector U can be defined by the vectors i, j, and k in the X-axis, Y-axis, and Z-axis directions of the machine three-dimensional coordinates from the surface creation formula.

  The analysis unit 31 analyzes this NC program, passes the feed axis position (X, Y, Z) to the distribution unit 32 for each block data, and feed axis position (X, Y, Z) and feed axis position. One block machining direction vector V (see FIG. 4) determined by (X, Y, Z) and the feed speed F are passed to the actual speed calculator 34, and one block machining direction vector V and the normal vector of the machining surface. U, feed speed F, spindle speed S, machining information L, work material information Q, and tool information H used are passed to the deflection correction amount calculation unit 35, and the spindle speed S is transmitted to the machine control interface unit 41. To pass.

  The actual speed calculation unit 34 corrects and corrects the feed speed F according to the feed axis position (X, Y, Z) and the machining direction vector V of one block, and calculates the actual speed Fr. The actual speed calculation unit 34 outputs the actual speed Fr to the distribution unit 32 and the deflection correction amount calculation unit 35.

  The distribution unit 32 determines the movement amount (ΔX, ΔY, ΔZ) of one block of each feed shaft according to the feed shaft position (X, Y, Z) from the analysis unit 31 and the actual speed Fr from the actual speed calculation unit 34. ) And the calculated movement amounts (ΔX, ΔY, ΔZ) are output to the feed axis command calculation output unit 33.

  The feed axis command calculation output unit 33 generates feed axis commands X *, Y *, Z * based on the movement amounts (ΔX, ΔY, ΔZ).

  The deflection correction amount calculation unit 35 calculates the deflection correction amount of the tool according to the normal vector V of the machining surface at the contact point A between the tool 19 and the workpiece W for each block data.

  More specifically, the deflection correction amount calculation unit 35 includes a normal vector U of the machining surface at the contact point A between the tool 19 and the workpiece W, a machining direction vector V of one block, an actual speed Fr, a spindle The rotational speed S, the machining information L, the work material information Q, and the used tool information H are input, and based on these information and the deflection correction amount calculation function, parameters, and used tool data stored in the database 36. A tool deflection correction value L is calculated.

  The used tool data stored in the database 36 uses the tool management number indicated by the used tool information H as a search key, and for each tool management number, the tool type Tk, the tool material Tz, the tool length Tla, the tool protrusion length Tlb, The tool diameter Td is defined in advance.

  The processing information L indicates a cutting method, that is, scanning line processing or contour line processing, and a processing type, that is, rough processing or finishing processing. Here, the amount of cutting is specified depending on whether it is roughing or finishing.

  The calculation formula of the tool deflection correction value L is expressed by the following formula.

L = f (U, V, Fr, S, Tk, Tz, Tla, Tlb, Td, L)
Where f is a deflection correction amount calculation function.

  The tool deflection compensation value L is composed of deflection compensation values Lx, Ly, and Lz for each feed axis, and all (V, U, Fr, S, Tk, Tz, Tla, Tlb, Td, L) are executed as block data. This is a factor for determining the amount of deflection in the radial direction of the tool at the time of cutting by.

  Tool deflection correction value L = f (V, U, Fr, S, Tk, Tz, Tla, Tlb, Td, L) The deflection correction value is calculated by an arithmetic expression identified by experimental measurement, empirical rules, or the like. Alternatively, it can be calculated with reference to various parameters for each radial deflection amount determination factor stored in the database 36.

  The feed axis command correction unit 37 is a feed axis position correction unit. The feed axis command X *, Y *, Z * is sent from the feed axis command calculation unit 33, and the tool deflection correction value L = ( Lx, Ly, Lz) is input, and feed axis commands X *, Y *, Z * for each feed axis are corrected according to the tool deflection correction values Lx, Ly, Lz for each feed axis. The feed axis command correction unit 37 outputs the corrected feed axis commands X *, Y *, and Z * to each of the axis control unit 38, the Y axis control unit 39, and the Z axis control unit 40.

  Thereby, shape processing is performed by the feed axis commands X *, Y *, Z * corrected according to the radial deflection amount of the tool 19, the coordinate position error due to the radial deflection of the tool is canceled, and the tool High-speed and high-precision shape processing is performed by three-axis control without performing five-axis control in which the central axis is directed in the normal direction of the processing surface.

  Next, one embodiment of an NC program creation device according to the present invention will be described with reference to FIG.

  The NC program creation device 60 is an automatic programming device such as a CAM, and creates an NC program of a numerical control device that performs shape machining using an orthogonal three-axis machining machine as shown in FIG.

  The NC program creation device 60 includes an NC block data creation unit 61, a normal vector calculation unit 62, a machining direction vector calculation unit 63, a deflection correction amount calculation unit 64, a database 65, and an output NC block data creation unit. 66.

  The NC block data creation unit 61 uses G data from CAD data and the like, G feed from a user input speed F, spindle rotation speed S, machining information L, work material information Q, tool information H, etc. NC block data including code and feed axis position (X, Y, Z) is created.

  The normal vector calculation unit 62 calculates the normal vector U of the machining surface at the contact point between the tool and the workpiece for each NC block data from the graphic data such as CAD data and the NC block data.

  As shown in FIG. 3 described above, the normal vector U of the machining surface at the contact point A between the tool 19 and the workpiece W is expressed by the tool center Tc from the contact point A between the tool 19 and the workpiece W. Is a vector indicating the direction toward the surface, and is calculated from the surface data of the drawing data by a surface creation formula. This normal vector U is also defined by vectors i, j, and k in the X-axis, Y-axis, and Z-axis directions of the machine three-dimensional coordinates.

  The machining direction vector calculation unit 63 calculates a machining direction vector V for one block from the feed axis position (X, Y, Z) of the NC block data created by the NC block data creation unit 61.

  The deflection correction amount calculation unit 64 calculates a tool deflection correction amount L corresponding to the normal vector U calculated by the normal vector calculation unit 62.

  More specifically, the deflection correction amount calculation unit 64 includes a normal vector U of the machining surface at the contact point A between the tool 19 and the workpiece W calculated by the normal vector calculation unit 62, and a machining direction vector calculation unit. The processing direction vector V of one block calculated by 63, the feed speed F of the user input from the keyboard 67, the spindle rotation speed S, the processing information L, the work material information Q, and the tool information H to be used are fetched. A deflection correction value L of the tool is calculated based on the deflection correction amount calculation function, parameters, and used tool data stored in the database 65.

  The used tool data stored in the database 65 uses the tool management number indicated by the used tool information H as a search key, and for each tool management number, the tool type Tk, the tool material Tz, the tool length Tla, the tool protrusion length Tlb, The tool diameter Td is defined in advance.

  The processing information L indicates a cutting method, that is, scanning line processing or contour line processing, and a processing type, that is, rough processing or finishing processing. Here, the amount of cutting is specified depending on whether it is roughing or finishing.

  The calculation formula of the tool deflection correction value L is expressed by the following formula.

L = f (U, V, F, S, Tk, Tz, Tla, Tlb, Td, L)
Where f is a deflection correction amount calculation function.

  The deflection correction value L is composed of the tool deflection correction values Lx, Ly, and Lz of each feed axis, and (V, U, F, S, Tk, Tz, Tla, Tlb, Td, L) are all executed as block data. This is a factor for determining the amount of deflection in the radial direction of the tool at the time of cutting by.

  Tool deflection correction value L = f (V, U, F, S, Tk, Tz, Tla, Tlb, Td, L) The deflection correction value is calculated by an arithmetic expression identified by experimental measurement, empirical rules, or the like. Alternatively, it can be calculated with reference to various parameters for each radial deflection amount determination factor stored in the database 65.

  The output NC block data creation unit 66 uses the feed axis position (X, Y, Z) of the NC block data created by the NC block data creation unit 61 to calculate the tool for each feed axis calculated by the deflection correction amount calculation unit 64. Correction is made with the deflection correction values Lx, Ly, and Lz, and NC block data for output is created.

  By performing shape processing using an NC program based on NC block data for output, coordinate position errors due to deflection in the radial direction of the tool can be canceled in shape processing using a general-purpose orthogonal 3-axis numerically controlled processing machine. High-speed and high-precision shape processing can be performed by three-axis control without performing five-axis control directed in the normal direction of the processing surface.

  The NC program creation device 60 described above is implemented by a computer executing a system program. An NC program creation program according to the present invention is CAM software, and a procedure for creating NC block data including feed axis position information from graphic data in a computer, a tool for each NC block data from graphic data, and The procedure for calculating the normal vector of the machining surface at the contact point with the workpiece, the procedure for calculating the tool deflection correction amount according to the calculated normal vector, and the calculated tool deflection correction amount. In response, the feed axis position information of the NC block data is corrected, and a procedure for creating NC block data for output is executed.

  The procedure for calculating the deflection correction amount in this NC program creation program is as follows: the normal vector of the machining surface, the machining direction vector of one block, the feed speed, the cutting depth, the spindle rotation speed, the cutting method, the tool type, the tool The deflection correction amount is calculated from at least one combination of a material, a tool length, a tool protrusion length, a tool diameter, and a workpiece material, or a combination thereof.

  Next, another embodiment of the NC program creating device according to the present invention will be described with reference to FIG.

  The NC program creation device 70 of this embodiment is also an automatic programming device such as CAM, and creates an NC program for a numerical control device that performs shape machining using an orthogonal three-axis machining machine as shown in FIG. To do.

  The NC program creating device 70 includes a polyhedral approximate model creating unit 71, a normal vector calculating unit 72, a deflection correction amount calculating unit 73, a database 74, a corrected polyhedral approximate model creating unit 75, and an NC block data creating unit 76. And have.

  The polyhedral approximate model creation unit 71 creates a polyhedral approximate model (three-dimensional model) using polygons or the like from graphic data such as CAD data.

  The normal vector calculation unit 72 calculates the normal vector Ua of each surface of the polyhedral approximate model created by the polyhedral approximate model creation unit 71. This normal vector Ua is calculated from the surface data of each surface of the polyhedral approximate model by a surface creation formula. This normal vector Ua is also defined by vectors i, j, and k in the X-axis, Y-axis, and Z-axis directions of the machine three-dimensional coordinates.

  The deflection correction amount calculating unit 73 calculates a tool deflection correction amount L corresponding to the normal vector Ua of each surface of the polyhedral approximate model calculated by the normal vector calculating unit 72 for each surface of the polyhedral approximate model. To do.

  More specifically, the deflection correction amount calculation unit 73 includes the normal vector Ua of each surface of the polyhedral approximate model calculated by the normal vector calculation unit 72, the feed speed F input by the user using the keyboard 77 and the like, and the spindle rotation speed. S, machining information L, work material information Q, and used tool information H are fetched, and the deflection correction value L of the tool is calculated based on these information and the deflection correction amount calculation function, parameters, and used tool data stored in the database 74. Is calculated.

  The used tool data stored in the database 74 uses the tool management number indicated by the used tool information H as a search key, and for each tool management number, the tool type Tk, the tool material Tz, the tool length Tla, the tool protrusion length Tlb, The tool diameter Td is defined in advance.

  The processing information L indicates a cutting method, that is, scanning line processing or contour line processing, and a processing type, that is, rough processing or finishing processing. Here, the amount of cutting is specified depending on whether it is roughing or finishing.

  The calculation formula of the tool deflection correction value L is expressed by the following formula.

L = f (Ua, F, S, Tk, Tz, Tla, Tlb, Td, L)
Where f is a deflection correction amount calculation function.

  The deflection correction value L is composed of tool deflection correction values Lx, Ly, and Lz for each feed axis, and (Ua, F, S, Tk, Tz, Tla, Tlb, Td, L) are all cut by executing block data. This is a factor that determines the radial deflection of the tool during machining.

  The tool deflection correction value L = f (Ua, F, S, Tk, Tz, Tla, Tlb, Td, L) can be calculated by an arithmetic expression identified by experimental measurement, empirical rules, etc. It is also possible to calculate with reference to various parameters for each radial deflection amount determination factor stored in the database 74.

  The corrected polyhedron approximate model creation unit 75 creates a corrected polyhedron approximation model that has been corrected to a shape that cancels tool deflection in accordance with the tool deflection correction amount L calculated by the deflection correction amount calculation unit 73. This corrected polyhedron approximation model is also a three-dimensional model using polygons or the like.

  The NC block data creating unit 76 creates each NC block data including feed axis position information from the corrected polyhedral approximate model created by the corrected polyhedral approximate model creating unit 75.

As a result, by performing shape machining by the NC program based on the NC block data created by the NC block data creation unit 76, the coordinate position due to deflection in the radial direction of the tool in shape machining by a general-purpose orthogonal three-axis numerically controlled machining machine The error can be canceled, and high-speed and high-precision shape machining can be performed by 3-axis control without performing 5-axis control in which the tool center axis is directed in the normal direction of the machining surface. This is also realized by a computer executing a system program. The NC program creation program according to the present invention is also CAM software, a procedure for creating a polyhedral approximate model from graphic data in a computer, a procedure for calculating a normal vector of each surface of the polyhedral approximate model, A procedure for calculating the deflection correction amount of the tool according to the normal vector of each surface of the calculated polyhedral approximation model, and a procedure for creating a corrected polyhedral approximation model corrected according to the calculated tool deflection correction amount; Then, a procedure for creating NC block data including feed axis position information from the created corrected polyhedral approximate model is executed.

  The procedure for calculating the deflection correction amount in this NC program creation program is as follows: the normal vector of each surface of the polyhedral approximation model, feed rate, depth of cut, spindle speed, cutting method, tool type, tool material, tool The deflection correction amount is calculated by a combination of at least one of the length, the tool protrusion length, the tool diameter, and the material of the workpiece, or a combination thereof.

  Next, another embodiment of the NC program creation device according to the present invention will be described with reference to FIG.

  The NC program creation device 80 of this embodiment is also an automatic programming device such as CAM, and creates an NC program for a numerical control device that performs shape machining using an orthogonal three-axis machining machine as shown in FIG. To do.

  The NC program creation device 80 includes a surface model creation unit 81, a normal vector calculation unit 82, a deflection correction amount calculation unit 83, a database 84, a correction surface model creation unit 85, and an NC block data creation unit 86. Have.

  The surface model creation unit 81 creates a surface model from graphic data such as CAD data.

  The normal vector calculation unit 82 calculates the normal vector Ua of each surface of the surface model created by the surface model creation unit 81. This normal vector Ua is calculated from the surface data of each surface of the surface model by a surface creation formula. This normal vector Ua is also defined by vectors i, j, and k in the X-axis, Y-axis, and Z-axis directions of the machine three-dimensional coordinates.

  The deflection correction amount calculation unit 83 calculates a tool deflection correction amount L corresponding to the normal vector Ua of each surface of the surface model calculated by the normal vector calculation unit 82 for each surface of the surface model.

  More specifically, the deflection correction amount calculation unit 83 includes the normal vector Ua of each surface of the surface model calculated by the normal vector calculation unit 82, the feed speed F input by the keyboard 87 and the like, and the spindle rotation speed S. The machining information L, the work material information Q, and the tool information H used are fetched, and the tool deflection correction value L is calculated based on these information and the deflection correction amount calculation function, parameters, and tool data stored in the database 74. calculate.

  The used tool data stored in the database 84 uses the tool management number indicated by the used tool information H as a search key, and for each tool management number, the tool type Tk, the tool material Tz, the tool length Tla, the tool protrusion length Tlb, The tool diameter Td is defined in advance.

  The processing information L indicates a cutting method, that is, scanning line processing or contour line processing, and a processing type, that is, rough processing or finishing processing. Here, the amount of cutting is specified depending on whether it is roughing or finishing.

  The calculation formula of the tool deflection correction value L is expressed by the following formula.

L = f (Ua, F, S, Tk, Tz, Tla, Tlb, Td, L)
Where f is a deflection correction amount calculation function.

  The deflection correction value L is composed of tool deflection correction values Lx, Ly, and Lz for each feed axis, and (Ua, F, S, Tk, Tz, Tla, Tlb, Td, L) are all cut by executing block data. This is a factor that determines the radial deflection of the tool during machining.

  The tool deflection correction value L = f (Ua, F, S, Tk, Tz, Tla, Tlb, Td, L) can be calculated by an arithmetic expression identified by experimental measurement, empirical rules, etc. It can also be calculated by referring to various parameters for each radial deflection amount determination factor stored in the database 84.

  The correction surface model creation unit 85 creates a correction surface model that has been corrected to a shape that cancels tool deflection in accordance with the tool deflection correction amount L calculated by the deflection correction amount calculation unit 83.

  The NC block data creation unit 86 creates each NC block data including feed axis position information from the correction surface model created by the correction surface model creation unit 85.

Thus, by performing shape processing by the NC program based on the NC block data created by the NC block data creation unit 86, the coordinate position due to the deflection in the radial direction of the tool in shape machining by a general-purpose orthogonal three-axis numerically controlled processing machine The NC program creation device 80 described above can cancel errors, and can perform high-speed and high-precision shape machining with three-axis control without performing five-axis control in which the tool center axis is directed in the normal direction of the machining surface. This is also realized by a computer executing a system program. The NC program creation program according to the present invention is also CAM software, and includes a procedure for creating a surface model from graphic data and a procedure for calculating a normal vector of each surface of the surface model. A procedure for calculating a deflection correction amount of the tool according to the normal vector of each surface of the surface model, a procedure for creating a correction surface model corrected according to the calculated tool deflection correction amount, and A procedure for creating NC block data including feed axis position information from the correction surface model is executed.

  The procedure for calculating the deflection correction amount in this NC program creation program is as follows: normal vector of each surface of the surface model, feed rate, depth of cut, spindle speed, cutting method, tool type, tool material, tool length The deflection correction amount is calculated from at least one combination of the tool protrusion length, the tool diameter, and the material of the workpiece, or a combination thereof.

  The NC program creation program according to the present invention is recorded on a computer-readable recording medium such as a hard disk, a floppy (registered trademark) disk, a CD-ROM, an MO, and a DVD, and is read from the recording medium by the computer. The program is executed and can also be distributed via a network such as the Internet via the recording medium as described above.

It is a block diagram which shows one Embodiment of the orthogonal three-axis numerical control processing machine used for implementation of the shape processing method by this invention. It is a block diagram which shows one Embodiment of the numerical control apparatus used for implementation of the shape processing method by this invention. It is explanatory drawing which shows the normal vector of the processing surface in the contact point of a tool and a workpiece. It is explanatory drawing which shows the normal vector of the processing surface in the contact point of a tool and a workpiece, and the processing direction vector of 1 block. It is a block diagram which shows one Embodiment of NC program creation apparatus by this invention. It is a block diagram which shows other embodiment of the NC program creation apparatus by this invention. It is a block diagram which shows other embodiment of the NC program creation apparatus by this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Machine tool 11 Bed 12 Work table 13 Cross rail 16 Saddle 17 Ram 18 Spindle head 19 Tool 20 Spindle motor 22 X-axis servo motor 23 Y-axis servo motor 25 Z-axis servo motor 30 Numerical control device (CNC)
31 Analysis Unit 32 Distribution Unit 33 Feed Axis Command Calculation Unit 34 Actual Speed Calculation Unit 35 Deflection Correction Amount Calculation Unit 36 Database 37 Feed Axis Command Correction Unit 38 X Axis Control Unit 39 Y Axis Control Unit 40 Z Axis Control Unit 41 Machine Control Interface 50 CAM
60 NC program creation device 61 NC block data creation unit 62 Normal vector calculation unit 63 Machining direction vector calculation unit 64 Deflection correction amount calculation unit 65 Database 66 NC block data creation unit for output 67 Keyboard 70 NC program creation device 71 Polyhedral approximation model Creation unit 72 Normal vector calculation unit 73 Deflection correction amount calculation unit 74 Database 75 Correction polyhedron approximate model creation unit 76 NC block data creation unit 77 Keyboard 80 NC program creation device 81 Plane model creation unit 82 Normal vector calculation unit 83 Deflection correction Quantity calculation unit 84 Database 85 Correction surface model creation unit 86 NC block data creation unit 87 Keyboard

Claims (17)

In a processing method for performing shape processing using an orthogonal three-axis numerical control processing machine,
For each block data including feed axis position information, using an NC program in which normal vector information indicating a normal vector of a machining surface at a contact point between a tool and a workpiece is described,
Analyzing the NC program for each block data,
For each analyzed block data, calculate the deflection correction amount of the tool according to the normal vector of the machining surface,
Correct the feed axis position according to the calculated tool deflection correction amount,
Shape processing method for performing shape processing according to the corrected feed axis position.   The deflection correction amount of the tool according to the normal vector of the machining surface is the normal vector of the machining surface, the machining direction vector of one block, the feed speed, the cutting depth, the spindle rotation speed, the cutting method, and the type of tool. The shape processing method according to claim 1, wherein the shape processing method is determined by at least one combination of a tool material, a tool length, a tool protrusion length, a tool diameter, and a workpiece material, or a combination thereof. In a numerical controller for an orthogonal three-axis machine,
Analysis for analyzing each block data of NC program in which normal vector information indicating the normal vector of the machining surface at the contact point between the tool and the workpiece is described for each block data including feed axis position information. And
For each block data analyzed by the analysis unit, a deflection correction amount calculation unit that calculates a deflection correction amount of the tool according to the normal vector of the machining surface,
A feed axis position correction unit that corrects the feed axis position according to the tool deflection correction amount calculated by the deflection correction amount calculation unit;
A numerical controller including   The deflection correction amount calculation unit includes a normal vector of the machining surface, a machining direction vector of one block, a feed speed, a cutting amount, a spindle rotation speed, a cutting method, a tool type, a tool material, a tool length, and a tool protrusion. The numerical control device according to claim 3, wherein the deflection correction amount is calculated by a combination of at least one of a length, a tool diameter, and a workpiece material, or a combination thereof.   A machine tool having the shape processing method according to claim 2 or the numerical control device according to claim 4. In an NC program creation device for creating an NC program of a numerical control device that performs shape machining using an orthogonal three-axis machine,
NC block data creation unit for creating NC block data including feed axis position information from graphic data;
A normal vector calculation unit for calculating a normal vector of the machining surface at the contact point between the tool and the workpiece for each NC block data from the graphic data;
A deflection correction amount calculation unit that calculates a deflection correction amount of the tool according to the normal vector calculated by the normal vector calculation unit;
NC block data for output is created by correcting feed axis position information of the NC block data created by the NC block data creation unit according to the tool deflection correction amount calculated by the deflection correction amount calculation unit. NC block data creation unit for output,
NC program creation device.   The deflection correction amount calculation unit includes a normal vector of the machining surface, a machining direction vector of one block, a feed speed, a cutting amount, a spindle rotation speed, a cutting method, a tool type, a tool material, a tool length, and a tool protrusion. The NC program creation device according to claim 6, wherein the deflection correction amount is calculated by a combination of at least one of a length, a tool diameter, and a workpiece material, or a combination thereof. On the computer,
A procedure for creating NC block data including feed axis position information from graphic data;
A procedure for calculating the normal vector of the machining surface at the contact point between the tool and the workpiece for each NC block data from the graphic data;
A procedure for calculating a deflection correction amount of the tool according to the calculated normal vector;
A procedure for correcting the feed axis position information of the NC block data according to the calculated tool deflection correction amount and creating NC block data for output,
NC program creation program for execution.   The deflection correction amount includes a normal vector of the machining surface, a machining direction vector of one block, a feed speed, a cutting amount, a spindle rotation speed, a cutting method, a tool type, a tool material, a tool length, a tool protrusion length, 9. The NC program creation program according to claim 8, wherein the NC program creation program is calculated by a combination of at least one of a tool diameter and a workpiece material or a combination of a plurality of them. In an NC program creation device for creating an NC program of a numerical control device that performs shape machining using an orthogonal three-axis machine,
A polyhedral approximate model creation unit that creates a polyhedral approximate model from figure data;
A normal vector calculation unit for calculating a normal vector of each surface of the polyhedral approximate model;
A deflection correction amount calculation unit that calculates a deflection correction amount of the tool according to a normal vector of each surface of the polyhedral approximate model calculated by the normal vector calculation unit;
A corrected polyhedral approximate model creating unit that creates a corrected polyhedral approximate model corrected according to the tool deflection correction amount calculated by the deflection correction amount calculating unit;
An NC block data creating unit for creating NC block data including feed axis position information from the corrected polyhedral approximate model created by the corrected polyhedral approximate model creating unit;
NC program creation device.   The deflection correction amount calculation unit includes a normal vector of each surface of the polyhedral approximate model, a machining direction vector of one block, a feed speed, a cutting amount, a spindle rotation speed, a cutting method, a tool type, a tool material, a tool The NC program creation device according to claim 10, wherein the deflection correction amount is calculated by a combination of at least one of a length, a tool protrusion length, a tool diameter, and a workpiece material, or a combination thereof. On the computer,
The procedure to create a polyhedral approximation model from figure data,
A procedure for calculating a normal vector of each surface of the polyhedral approximate model;
A procedure for calculating a deflection correction amount of the tool according to the normal vector of each surface of the calculated polyhedral approximate model;
A procedure for creating a corrected polyhedral approximate model corrected according to the calculated tool deflection correction amount;
A procedure for creating NC block data including feed axis position information from the created corrected polyhedron approximation model,
NC program creation program for execution.   The deflection correction amount includes the normal vector of each surface of the polyhedral approximate model, feed rate, depth of cut, spindle rotation speed, cutting method, tool type, tool material, tool length, tool ejection length, tool diameter, 13. The NC program creation program according to claim 12, wherein the calculation is performed by at least one combination of workpiece materials or a plurality of combinations thereof. In an NC program creation device for creating an NC program of a numerical control device that performs shape machining using an orthogonal three-axis machine,
A surface model creation unit for creating a surface model from graphic data;
A normal vector calculation unit for calculating a normal vector of each surface of the surface model;
A deflection correction amount calculation unit that calculates a deflection correction amount of the tool according to the normal vector of each surface of the surface model calculated by the normal vector calculation unit;
A correction surface model creation unit that creates a correction surface model corrected according to the tool deflection correction amount calculated by the deflection correction amount calculation unit;
An NC block data creation unit for creating NC block data including feed axis position information from the correction surface model created by the correction surface model creation unit;
NC program creation device.   The deflection correction amount calculation unit includes a normal vector of each surface of the surface model, a machining direction vector of one block, a feed speed, a cutting amount, a spindle rotation speed, a cutting method, a tool type, a tool material, a tool length. 15. The NC program creation device according to claim 14, wherein the deflection correction amount is calculated by a combination of at least one of a tool protrusion length, a tool diameter, and a workpiece material, or a combination thereof. On the computer,
To create a surface model from figure data,
A procedure for calculating a normal vector of each surface of the surface model;
A procedure for calculating a deflection correction amount of the tool according to the normal vector of each surface of the calculated surface model;
A procedure for creating a correction surface model corrected according to the calculated tool deflection correction amount;
The procedure to create NC block data including feed axis position information from the created correction surface model,
NC program creation program for execution. The deflection correction amount includes the normal vector of each surface of the surface model, feed speed, depth of cut, spindle rotation speed, cutting method, tool type, tool material, tool length, tool protrusion length, tool diameter, coverage. 17. The NC program creation program according to claim 16, wherein the calculation is performed by at least one combination of workpiece materials or a plurality of combinations thereof.

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