JP2017117459A - Multiaxial nc processing wood lathe system, tool root generation program, and recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To execute a lathe machining process in a safe and time-efficient manner as a whole including inexpensive and fine uneven processing when an end surface and a side surface of a wood material are subjected to three-dimensional processing.SOLUTION: A multiaxial NC processing wood lathe system 1 executes three-dimensional processing with an actual disk type rotary tool 20 by one feed operation only by a tool route of a virtual thin disk 21 previously generated based on a three-dimensional shape model 2 of a product whose surface is divided by a triangle and inputted to a computer in order to cut a wood material W rotating around a C axis by chucking to the C axis capable of controlling a revolving angle. After that, a micro uneven processing part in the product of the three-dimensional shape to be machined of the workpiece after preliminary grinding is efficiently subjected to cutting using an actual spherical rotary tool 31 on the same stage as the disk type rotary tool 20 by a tool route of a virtual spherical body 32 previously generated based on the same three-dimensional shape model 2 without removing the wood material. The spherical rotary tool 31 turns around a B axis so as to continue facing an arbitrary point Zh on a Z axis.SELECTED DRAWING: Figure 1

Description

  The present invention provides a tool for generating a tool path necessary for cutting a product when a disk-type rotary tool and a spherical rotary tool whose tip is a spherical or hemispherical rotary tool are used as a cutting tool of a woodworking lathe device. The present invention relates to a technique for providing a multi-axis NC woodworking lathe system having a path generation method, the above-described tool path generation method, a tool path generation program, and a recording medium.

  Conventionally, in order to process a three-dimensional product, a 5-axis control machine tool can be used as shown in Patent Document 1. A so-called multi-axis processing machine such as a machining center can control the direction of the tool, so that it can process a complicated three-dimensional shape such as an intricate shape.

  The inventor of the present application has developed a three-axis NC woodworking lathe system using a disk-type rotary tool in order to process a three-dimensional product shown in Patent Document 2. The system assumes that the three-dimensional shape model in which the surface of the three-dimensional shape of the product is divided into triangles is chucked on the C-axis, which is a turning axis that can control the turning angle on the three-axis NC woodworking lathe. Further, it is characterized in that a tool path for cutting with a disk-type rotary tool is calculated in advance. The system can process a three-dimensional shape in a short time only by cutting during one feeding operation.

JP 2014-94425 A Japanese Patent No. 4784767

  When a woodworking material is three-dimensionally processed, when a multi-axis processing machine such as a 5-axis control machine tool as shown in Patent Document 1 is used, it becomes expensive hardware. In addition, the tool path cannot be calculated unless it is a combination of a Cartesian coordinate system and a rotating coordinate system, resulting in complicated and expensive software. Furthermore, since the tool used has a cylindrical shape such as an end mill or a drill or a spherical tip, a deep cut cannot be expected. Moreover, in order to process a fine shape, it is necessary to go through a step from a large size tool to a gradually smaller size tool, which increases the processing time.

The 3-axis NC woodworking lathe system disclosed in Patent Document 2 turns a disk-shaped rotary tool in the X-axis direction based on a pre-calculated tool path while turning the woodwork material chucked on the C-axis of the chuck around the C-axis. By moving in the Z-axis direction, cutting can be efficiently performed in a short time compared to a 5-axis control machine tool as shown in Patent Document 1. Further, since a three-dimensional lathe can be used for three-dimensional machining, the apparatus is less expensive than a five-axis machine.
However, cutting with a disk-type rotary tool is limited in the shape that can be processed by the thickness and radius of the rotary tool, and the thickness and radius of the disk-type rotary tool are reduced in order to perform finer cutting. It is also true that there is a certain structural limit. Therefore, when performing further fine cutting processing, it is necessary to use a 5-axis processing machine, or the complicated and expensive software described above is required, resulting in longer processing time and higher cost. There was a problem of inviting.

  Further, when the disk-type rotary tool disclosed in Patent Document 2 cuts out a three-dimensional shape, the disk-type rotary tool is always oriented in a direction perpendicular to the rotation axis of the woodworking material. Therefore, when the surface of the three-dimensional shape model is inclined with respect to the rotation axis when the rotary disk tool is cut through the path of the spiral machining point with respect to the woodworking material, the disk type rotary tool A spiral cutter mark by the edge appears. When the inclination angle of the surface is small, the surface roughness due to the cutter mark is small. For example, a surface that is parallel to the rotation axis has good surface roughness. However, when the inclination angle of the surface is large, the surface roughness increases. That is, the larger the tilt angle, the worse the surface roughness. Therefore, there arises a problem that the polishing time is increased and the cost is increased.

  Moreover, the woodworking material cut with the disk-type rotary tool shown in Patent Document 2 is usually a square member having a square cross section. When a three-dimensional shape is cut out from a regular square material, the cutting allowance between the square outer shape and the contour of the three-dimensional shape becomes powdered chips by the disk-type rotary tool. When the woodworking material is small, for example, when one side of the square is several centimeters, the power required for cutting the machining allowance is small. However, if a square material with a side of 10.5 cm is used as a building material, a large amount of power is required, and wasteful energy is consumed.

  The present invention has been made in view of such circumstances, and when processing a woodworking material three-dimensionally, it is inexpensive and does not require complicated and expensive hardware and software, and fine uneven processing is also possible. In addition, an object of the present invention is to provide a multi-axis NC woodworking lathe system, a tool path generation method, a tool path generation program, and a recording medium that can perform lathe machining efficiently in terms of time.

The invention related to the multi-axis NC woodworking lathe system according to claim 1 is for chucking a C-axis which is a swivel axis whose swivel angle can be controlled and cutting a woodworking material swiveling around the C-axis.
A disk-type rotary tool that can move in the Z-axis direction and the X-axis direction orthogonal to the Z-axis, and a B-axis that is installed on the same stage as the disk-type rotary tool and moves in the XZ plane and is perpendicular to the XZ plane A multi-axis NC woodworking lathe system having a spherical rotating tool with a spherical or hemispherical tip that can be swiveled around,
Suppose that the three-dimensional shape model of the product whose surface is divided into triangles and input to the computer is chucked on the C axis,
Assuming that the outer periphery of a virtual thin disk having the same shape as the disk-type rotary tool moves in the Z-axis direction while maintaining a state in contact with the rotating three-dimensional shape model, Obtaining the X coordinate of the center of rotation of the virtual thin disk for an arbitrary turning angle θ and an arbitrary Z coordinate of the outer periphery of the virtual thin disk,
While maintaining the state in which the surface of the virtual sphere having the tip shape of the sphere having the same diameter as the spherical rotary tool is in contact with the three-dimensional shape model turning around the C axis, Assuming that the rotation axis always turns to the arbitrary point Zh on the Z-axis so as to turn around the B-axis,
When obtaining the X and Z coordinates of the center of the sphere with respect to an arbitrary turning angle α formed by an arbitrary turning angle θ of the C axis and a Z axis of the rotating shaft of the spherical rotary tool,
A first processing point when the surface of the sphere and the vertex of the triangle constituting the three-dimensional shape model are in contact with each other, and a second processing point when the surface of the sphere and the side of the triangle constituting the three-dimensional shape model are in contact with each other Machining points that should contribute to actual machining from among the three machining point candidates: machining points and third machining points when the surface of the sphere touches the triangular plane that constitutes the three-dimensional shape model It is characterized in that the X coordinate and Z coordinate of the center of the sphere are obtained by extracting only one.

  The invention according to claim 2 relates to the multi-axis NC woodworking lathe system according to claim 1, wherein the three-dimensional shape model is a polygon polygon for a product whose surface is divided into polygon polygons having a three-dimensional curved surface. It is characterized in that it has vertices on the curved surface and is divided into triangles connected by straight lines.

The invention according to claim 3 is the multi-axis NC woodworking lathe system according to claim 1 or 2, wherein the disk-type rotary tool is movable in the Z-axis direction and the X-axis direction orthogonal to the Z-axis. , Can pass around the center of rotation of the disk-type rotary tool, and can turn around the D axis perpendicular to the XZ plane,
The outer circumference of a virtual thin disk having the same shape as the disk-type rotary tool moves in the Z-axis direction while maintaining a state in contact with the three-dimensional shape model that is turning, and the virtual thin disk Assuming that the direction is perpendicular to the surface of the three-dimensional shape model,
From the contact point between the outer periphery of the virtual thin disk and the surface of the three-dimensional shape model, a normal vector whose length in the normal direction is the radius of the virtual thin disk is calculated, and the tip of the normal vector A rotation angle γ obtained by rotating the three-dimensional shape model around the Z axis until a straight line perpendicular to the Z axis from the position coincides with the XZ plane, and a projection component of the normal vector onto the XZ plane forms an X axis. The X-coordinate and Z-coordinate of the center of the virtual thin disk are obtained with respect to the angle β and the arbitrary turning angle θ of the C axis.

The invention related to the multi-axis NC woodworking lathe system according to claim 4 is the above-mentioned item 3, wherein the virtual thin disk is defined by a tool coordinate system including a number of points around the surface thereof.
When it is assumed that the virtual thin disk is swung by the angle β in order to orient the perpendicular thin disk in a direction perpendicular to the surface of the three-dimensional shape model, at least one of a plurality of points defined in the tool coordinate system is used. If the point is inside the three-dimensional shape model, it is determined that the virtual thin disk has interfered with the three-dimensional shape model,
The direction of the virtual thin disk is swung by an angle β-90 °, and the tip of the virtual thin disk is positioned so as to contact the machining point of the three-dimensional shape model.

  The invention related to the multi-axis NC woodworking lathe system according to claim 5 is any one of the above items 1 to 4, wherein the arbitrary point Zh on the Z-axis approximates the tip of the product shape to a hemisphere. It is characterized by being the Z coordinate of the center of the bottom surface of.

  The invention according to claim 6 relates to the multi-axis NC woodworking lathe system according to any one of items 1 to 5, wherein the spherical rotary tool has a spherical or hemispherical woodworking ball bit or woodworking router bit. It is characterized by being.

The invention related to the multi-axis NC woodworking lathe system according to claim 7 includes a band saw blade that travels in parallel with a direction orthogonal to the C axis in the above item 1, 2, or 3, and the band saw blade as a whole. A band saw machine capable of moving in a Z-axis direction parallel to the Z-axis and an F-direction orthogonal to the Z-axis and capable of turning so as to incline the direction of the band saw blade with respect to the Z-axis direction;
When the virtual band saw tool having the same shape as the band saw blade of the band saw machine slices in the Z-axis direction parallel to the Z-axis with respect to the three-dimensional shape model with the C-axis turning angle θ being zero degrees, the Z-axis Assuming movement in the F direction perpendicular to the direction and the Z axis,
A large number of virtual slice sections parallel to the XY plane are formed at appropriate intervals in the Z-axis direction with respect to the three-dimensional shape model, and a maximum point Fmax and a minimum point Fmin in the + F direction are calculated in each virtual slice section. The maximum contour line connecting Fmax and the minimum contour line connecting each Fmin are calculated, and the maximum offset line for the maximum contour line and the minimum offset line for the minimum contour line are calculated. Then, at least one of the maximum part offset line and the minimum part offset line is obtained as a tool path of the virtual band saw tool.

  The invention related to the multi-axis NC woodworking lathe system according to claim 8 is the above-described item 7, wherein the maximum portion contour line and the minimum portion contour line are obtained by turning the three-dimensional shape model at a turning angle θ of an appropriate pitch of the C axis. Each time it is rotated, it is stopped and calculated, and the maximum part offset line and the minimum part offset line corresponding to each of the maximum part outline and the minimum part outline are calculated and obtained.

The invention according to claim 9 relates to the multi-axis NC woodworking lathe system according to claim 1, wherein the polishing belt includes a polishing belt that runs parallel to a direction orthogonal to the C-axis. Is a belt sander that can move in the Z-axis direction parallel to the Z-axis and the F-direction orthogonal to the Z-axis, and can change the direction of the polishing belt to be inclined with respect to the Z-axis direction. With
When the virtual polishing tool having the same shape as the polishing belt of the belt sander polishes the three-dimensional shape model with the C-axis turning angle θ being zero degrees, the Z direction and the F direction perpendicular to the Z axis On the premise of moving to
A large number of virtual slice sections parallel to the XY plane are formed at appropriate intervals in the Z-axis direction with respect to the three-dimensional shape model, and a maximum point Fmax and a minimum point Fmin in the + F direction are calculated in each virtual slice section. The maximum contour line connecting Fmax and the minimum contour line connecting each Fmin are calculated, and at least one of the maximum contour line and the minimum contour line is used as a tool of the virtual polishing tool. It is characterized by being obtained as a route.

  The invention related to the multi-axis NC woodworking lathe system according to claim 10 is characterized in that, in the above-mentioned item 9, the maximum portion contour line and the minimum portion contour line are obtained by turning the three-dimensional shape model at a turning angle θ of an appropriate pitch of the C axis. It is characterized by being obtained by calculation after stopping every rotation.

The invention relating to the tool path generation method according to claim 11 includes a first tool path generation method necessary for three-dimensional machining using a disk-type rotary tool and a spherical rotary tool whose tip is a spherical or hemispherical rotary tool. A tool path generation method combining the second tool path generation method necessary for three-dimensional machining using
Assuming that the three-dimensional shape model of the product whose surface is divided into triangles and input to the computer is chucked to the C axis, which is the pivot axis that can control the pivot angle on a multi-axis NC woodworking lathe,
In the first tool path generation method, the outer periphery of a virtual thin disk having the same shape as that of the disk-type rotary tool is kept in contact with the three-dimensional shape model that is turning around the C axis. The tool path is obtained by obtaining the X coordinate of the rotation center of the virtual thin disk with respect to the arbitrary turning angle θ of the C axis and the arbitrary Z coordinate of the outer periphery of the virtual thin disk on the assumption that the axis moves. Produces
In the second tool path generation method, the surface of the virtual sphere having the sphere tip shape having the same diameter as that of the spherical rotary tool is maintained in contact with the three-dimensional shape model turning around the C axis. However, assuming that the rotational axis of the spherical rotary tool always moves to the arbitrary point Zh on the Z axis and moves in the XZ plane and turns around the B axis perpendicular to the XZ plane, In order to obtain the X coordinate and the Z coordinate, when an arbitrary turning angle θ of the C axis and an arbitrary turning angle α formed by the Z axis of the rotating shaft in the spherical rotary tool,
Both the three-dimensional shape model and the spherical rotating tool are simultaneously rotated in the opposite direction by the same turning angle as the turning angle α around the straight line passing through the Zh at a right angle to the XZ plane, thereby converting the spherical coordinates. Make the rotation axis of the rotary tool coincide with the Z axis,
The Z coordinate group of the center of the sphere when the surface of the sphere and the apex of the triangle constituting the three-dimensional shape model are in contact with the surface of the sphere and the sides of the triangle constituting the three-dimensional shape model Z coordinate group of the center of the sphere at the time, and the Z coordinate group of the center of the sphere when the surface of the sphere is in contact with the triangular plane constituting the three-dimensional shape model, Among them, the Z coordinate farthest in the + Z direction located outside the three-dimensional shape model from the point Z = Zh is adopted, and the adopted Z coordinate is rotated around the straight line passing through the Zh at right angles to the XZ plane. The X axis and Z coordinate obtained by turning in the positive direction by the angle α and converting the rotational coordinates are used as a tool path.

  The invention according to claim 12, wherein the three-dimensional shape model is a curved surface of the polygonal polygon with respect to a product whose surface is divided into polygonal polygons having a three-dimensional curved surface. It is characterized by assuming that it is divided into triangles with vertices on top and vertices connected by straight lines.

The invention related to the tool path generation method according to claim 13 is the above 11 or 12, wherein the first tool path generation method includes an outer periphery of a virtual thin disk having the same shape as the disk type rotary tool. , Moving in the Z-axis direction while maintaining a state in contact with the three-dimensional shape model turning around the C axis, and the direction of the virtual thin disk is perpendicular to the surface of the three-dimensional shape model Assuming that
From the contact point between the outer periphery of the virtual thin disk and the surface of the three-dimensional shape model, a normal vector whose length in the normal direction is the radius of the virtual thin disk is calculated, and the tip of the normal vector A rotation angle γ obtained by rotating the three-dimensional shape model around the Z axis until a straight line perpendicular to the Z axis from the position coincides with the XZ plane, and a projection component of the normal vector onto the XZ plane forms an X axis. The X-coordinate and Z-coordinate of the center of the virtual thin disk are obtained with respect to the angle β and the arbitrary turning angle θ of the C axis.

The invention according to claim 14, wherein the virtual thin disk is defined by a tool coordinate system consisting of a large number of points around the surface thereof in the above-mentioned item 13,
When it is assumed that the virtual thin disk is swung by the angle β in order to orient the perpendicular thin disk in a direction perpendicular to the surface of the three-dimensional shape model, at least one of a plurality of points defined in the tool coordinate system is used. If the point is inside the three-dimensional shape model, it is determined that the virtual thin disk has interfered with the three-dimensional shape model,
The direction of the virtual thin disk is swung by an angle β-90 °, and the tip of the virtual thin disk is positioned so as to contact the machining point of the three-dimensional shape model.

The invention according to claim 15 is the tool path generation method according to any one of claims 11 to 14, further comprising a band saw blade that travels in parallel with a direction orthogonal to the C axis, and the band saw blade as a whole is a Z axis. 3D using a band saw that can move in the Z-axis direction parallel to the Z-axis and the F-direction orthogonal to the Z-axis, and can change the direction of the band saw blade so as to be inclined with respect to the Z-axis direction. Add a third tool path generation method necessary for machining,
As the third tool path generation method, a virtual band saw tool having the same shape as the band saw blade of the band saw machine is parallel to the Z axis with respect to the three-dimensional shape model with the C axis turning angle θ being zero degrees. When slicing in the Z-axis direction, assuming that the Z-axis direction and the F-direction perpendicular to the Z-axis move,
A large number of virtual slice sections parallel to the XY plane are formed at appropriate intervals in the Z-axis direction with respect to the three-dimensional shape model, and a maximum point Fmax and a minimum point Fmin in the + F direction are calculated in each virtual slice section. The maximum contour line connecting Fmax and the minimum contour line connecting each Fmin are calculated, and the maximum offset line for the maximum contour line and the minimum offset line for the minimum contour line are calculated. A tool path of the virtual band saw tool is generated for at least one of the maximum part offset line and the minimum part offset line.

The invention according to a sixteenth aspect of the present invention is the tool path generation method according to any one of the eleventh to fifteenth aspects, further comprising a polishing belt that rotates in parallel with a direction orthogonal to the C axis, and the polishing belt is Z as a whole. Tertiary using a belt sander that can move in the Z-axis direction parallel to the axis and the F-direction orthogonal to the Z-axis, and can change the direction of the polishing belt so as to be inclined with respect to the Z-axis direction. Add the fourth tool path generation method necessary for original machining,
As the fourth tool path generation method, when a virtual polishing tool having the same shape as the polishing belt of the belt sander is polished with respect to the three-dimensional shape model in which the turning angle θ of the C axis is zero degrees, On the premise of moving in the Z-axis direction and the F-direction orthogonal to the Z-axis,
A large number of virtual slice sections parallel to the XY plane are formed at appropriate intervals in the Z-axis direction with respect to the three-dimensional shape model, and a maximum point Fmax and a minimum point Fmin in the + F direction are calculated in each virtual slice section. The maximum contour line connecting Fmax and the minimum contour line connecting each Fmin are calculated, and at least one of the maximum contour line and the minimum contour line is used as a tool of the virtual polishing tool. It is characterized by generating a route.

The invention related to the tool path generation program according to claim 17 is a turning axis capable of controlling a turning angle on a multi-axis NC woodworking lathe from a three-dimensional shape model of a product whose surface is divided into triangles and inputted to a computer. The first tool path generation program required for three-dimensional machining using a disk-type rotary tool and a spherical rotary tool whose tip is a spherical or hemispherical rotary tool are used. A tool path generation program that combines a second tool path generation program necessary for three-dimensional machining, and the first and second tool path generation programs are configured as follows.
The first tool path generation program maintains a state in which the outer periphery of a virtual thin disk having the same shape as the disk-type rotary tool is in contact with the three-dimensional shape model turning around the C axis. On the premise of moving in the axial direction, by determining the X coordinate of the center of rotation of the virtual thin disk with respect to the arbitrary turning angle θ of the C axis and the arbitrary Z coordinate of the outer periphery of the virtual thin disk, A tool path of the disk-type rotary tool is used.
The second tool path generation program maintains a state in which the surface of a virtual sphere having a sphere tip shape having the same diameter as that of the spherical rotary tool is in contact with the three-dimensional shape model turning around the C axis. However, the X coordinate and Z of the center of the sphere are assumed on the assumption that the rotating axis of the spherical rotary tool always moves to the arbitrary point Zh on the Z-axis and moves in the XZ plane and rotates in the direction orthogonal to the XZ plane. In order to obtain the coordinates, when the arbitrary turning angle α between the arbitrary turning angle θ of the C axis and the Z axis of the rotating shaft in the spherical rotating tool is set, both the three-dimensional shape model and the spherical rotating tool are At the same time, the rotational axis of the spherical rotary tool is made to coincide with the Z-axis by turning in the opposite direction by the same turning angle as the turning angle α around the straight line perpendicular to the XZ plane and passing through the Zh. ,
The Z coordinate group of the center of the sphere when the surface of the sphere and the apex of the triangle constituting the three-dimensional shape model are in contact with the surface of the sphere and the sides of the triangle constituting the three-dimensional shape model Z coordinate group of the center of the sphere at the time, and the Z coordinate group of the center of the sphere when the surface of the sphere is in contact with the triangular plane constituting the three-dimensional shape model, Among them, the Z coordinate farthest from the point Z = Zh in the + Z direction located outside the three-dimensional shape model is adopted,
The X coordinate and Z coordinate obtained by turning the adopted Z coordinate in the positive direction by the turning angle α around the straight line perpendicular to the XZ plane and passing through the Zh are converted into the rotational coordinates of the spherical rotary tool. It is characterized by a tool path.

  An invention according to a tool path generation program according to claim 18 is the method according to claim 17, wherein the three-dimensional shape model is formed on a curved surface of the polygon polygon with respect to a product whose surface is divided into polygon polygons having a three-dimensional curved surface. It is characterized by assuming that it is divided into triangles that have vertices and are connected by straight lines.

The invention related to the tool path generation program according to claim 19 is the above 17 or 18, wherein the first tool path generation program has an outer periphery of a virtual thin disk having the same shape as the disk-type rotary tool. While moving in the Z-axis direction while maintaining a state in contact with the three-dimensional shape model turning around the C-axis, the direction of the virtual thin disk is made perpendicular to the surface of the three-dimensional shape model Assuming that
From the contact point between the outer periphery of the virtual thin disk and the surface of the three-dimensional shape model, a normal vector whose length in the normal direction is the radius of the virtual thin disk is calculated, and the tip of the normal vector A rotation angle γ obtained by rotating the three-dimensional shape model around the Z axis until a straight line perpendicular to the Z axis from the position coincides with the XZ plane, and a projection component of the normal vector onto the XZ plane forms an X axis. The X-coordinate and Z-coordinate of the center of the virtual thin disk are obtained with respect to the angle β and the arbitrary turning angle θ of the C axis.

The invention related to the tool path generation program according to claim 20 is the above-described item 19, wherein the virtual thin disk is defined by a tool coordinate system including a number of points around the surface thereof.
When it is assumed that the virtual thin disk is swung by the angle β in order to orient the perpendicular thin disk in a direction perpendicular to the surface of the three-dimensional shape model, at least one of a plurality of points defined in the tool coordinate system is used. If the point is inside the three-dimensional shape model, it is determined that the virtual thin disk has interfered with the three-dimensional shape model,
The direction of the virtual thin disk is swung by an angle β-90 °, and the tip of the virtual thin disk is positioned so as to contact the machining point of the three-dimensional shape model.

The invention according to claim 21 is the tool path generation program according to any one of items 17 to 20, further comprising a band saw blade that travels in parallel with a direction orthogonal to the C axis, and the band saw blade as a whole is a Z axis. 3D using a band saw that can move in the Z-axis direction parallel to the Z-axis and the F-direction orthogonal to the Z-axis, and can change the direction of the band saw blade so as to be inclined with respect to the Z-axis direction. Add a third tool path generation program necessary for machining,
In the third tool path generation program, a virtual band saw tool having the same shape as the band saw blade of the band saw machine is parallel to the Z axis with respect to the three-dimensional shape model in which the turning angle θ of the C axis is zero degrees. When slicing in the Z-axis direction, assuming that the Z-axis direction and the F-direction perpendicular to the Z-axis move,
A large number of virtual slice sections parallel to the XY plane are formed at appropriate intervals in the Z-axis direction with respect to the three-dimensional shape model, and a maximum point Fmax and a minimum point Fmin in the + F direction are calculated in each virtual slice section. The maximum contour line connecting Fmax and the minimum contour line connecting each Fmin are calculated, and the maximum offset line for the maximum contour line and the minimum offset line for the minimum contour line are calculated. Then, at least one of the maximum part offset line and the minimum part offset line is used as a tool path of the virtual band saw tool.

An invention according to a tool path generation program according to a twenty-second aspect includes the polishing belt according to any one of the seventeenth to twenty-first aspects, wherein the polishing belt travels in parallel with a direction orthogonal to the C axis, and the polishing belt as a whole is a Z axis 3D using a belt sander that can move in the Z-axis direction parallel to the Z-axis and the F-direction orthogonal to the Z-axis, and can change the direction of the polishing belt so as to be inclined with respect to the Z-axis direction. Add the fourth tool path generation program necessary for machining,
As the fourth tool path generation program, when a virtual polishing tool having the same shape as the polishing belt of the belt sander is polished with respect to the three-dimensional shape model in which the turning angle θ of the C axis is zero degrees, On the premise of moving in the Z-axis direction and the F-direction orthogonal to the Z-axis,
A large number of virtual slice sections parallel to the XY plane are formed at appropriate intervals in the Z-axis direction with respect to the three-dimensional shape model, and a maximum point Fmax and a minimum point Fmin in the + F direction are calculated in each virtual slice section. The maximum contour line connecting Fmax and the minimum contour line connecting each Fmin are calculated, and at least one of the maximum contour line and the minimum contour line is used as a tool of the virtual polishing tool. It is characterized by generating a route.

  A recording medium according to a twenty-second aspect records the tool path generation program according to any one of the seventeenth to twenty-first aspects.

According to the present invention, a tool path is generated by a virtual thin disk that is in contact with the three-dimensional shape model of the product, and then a virtual spherical tool path that is in contact with the side surface from the tip of the three-dimensional shape model is also generated. By doing so, the following effects can be obtained.
Based on the tool path by the virtual thin disk, first, rough machining is performed only by a single feed operation with a disk-type cutting tool, and then the spherical rotary tool is immediately based on the tool path by the virtual sphere without removing the material. It is possible to process fine irregularities. As a result, a series of steps from rough machining to fine machining can be continuously performed on one processing machine, and as a result, fine three-dimensional lathe machining can be performed in a short time and It becomes possible to carry out with high accuracy. As a result, it is possible to perform efficient three-dimensional processing in a short time as a whole, including low-priced processing that is inexpensive and does not require complicated and expensive hardware and software.

  The three-dimensional shape model is a three-dimensional shape model of a three-dimensional product whose surface is divided by a triangle, or a three-dimensional shape model of a product whose surface is divided into polygon polygons of a three-dimensional curved surface. Even applicable.

  Further, by controlling the disk-type rotary tool so that it is directed in the normal direction with respect to the surface of the three-dimensional shape model, the roughness of the processed surface is reduced, and a processed surface corresponding to the polished surface is obtained. Further, since the disk-type rotary tool can swing so as to face in the tangential direction so as not to interfere with the three-dimensional shape model, the roughness of the processed surface is reduced, and a processed surface corresponding to the polished surface is obtained. As a result, the time for the polishing process can be shortened.

  In addition, a band saw machine having a band saw blade that runs parallel to the direction orthogonal to the C axis is further provided, so that the cutting allowance between the outer shape of the woodworking material and the contour of the three-dimensional shape can be reduced with less energy, and Can be cut off in a short time.

  Further, by further comprising a belt sander having a polishing belt that runs parallel to the direction orthogonal to the C axis, the three-dimensional shape is cut out from the woodworking material by a disk-type rotary tool or a spherical rotary tool. It is automatically polished with a polishing belt against the contour of As a result, the polishing process can be shortened and labor can be saved.

1 is a perspective view schematically showing a multi-axis NC woodworking lathe system according to an embodiment of the present invention. (A) is a perspective view showing a virtual three-dimensional shape model chucked on the C-axis of a multi-axis NC woodworking lathe, a virtual thin disk, and a virtual sphere. (B) is the side view seen from the Z-axis direction of (a). It is a schematic explanatory drawing which shows the geometric positional relationship with the triangle of the surface of the virtual three-dimensional shape model located in the space area | region of a virtual thin disk. FIG. 6 is a schematic diagram illustrating a method for obtaining a center X coordinate of a circle passing through a point A. (A) is a top view which shows the state in which a spherical rotary tool turns around a B-axis, always facing the point Z = Zh. (B) is a plan view showing a state in which the virtual three-dimensional model and the spherical rotary tool of (a) are rotationally converted in the reverse direction with the point Z = Zh as the origin. It is a schematic perspective view which shows the geometric positional relationship with the triangle of the surface of the virtual three-dimensional shape model located in the space area | region of a virtual sphere. It is the schematic which shows the Z coordinate of the center of the virtual sphere in a 1st process point. It is the schematic which shows the Z coordinate of the center of the virtual sphere in a 2nd process point. It is the schematic which shows Z coordinate of the center of the virtual sphere in the 3rd processing point. (A)-(c) is a schematic perspective view in the three-dimensional shape model of a product by which the surface of the polygon polygon defined by a three-dimensional curved surface was divided | segmented into the triangle. It is the top view which the virtual thin disk contacted the normal direction with respect to the surface of the virtual three-dimensional shape model. It is a perspective view explaining obtaining the rotation center coordinate of the virtual thin disk which contacted the surface of the virtual three-dimensional shape model in the normal direction. It is the XZ top view which looked at the state of FIG. 12 from the Y-axis direction. It is the side view which looked at the state of Drawing 12 from the Z-axis direction. It is a perspective view which shows an example of the product which has a dent. FIG. 16 is an XZ plan view showing a state in which the three-dimensional shape model of the product of FIG. 15 is virtually cut with a virtual thin disk. It is a perspective view which shows the state which cuts off the woodwork material with the band saw blade of a band saw machine. It is a perspective view which shows the slice cross section of a three-dimensional shape model. It is a perspective view which shows the maximum part outline and minimum part outline of a three-dimensional shape model. It is the schematic which shows the maximum part offset line with respect to the maximum part outline. It is sectional drawing for measuring the limit of the curvature radius of a cutting curve from the section of the band saw blade at the time of cutting woodworking material. (A)-(d) is a schematic perspective view which shows a series of operation | movement which cuts a three-dimensional shape from woodworking material using a disk type | mold rotary tool and a band saw blade. It is a perspective view which shows the state which grinds woodwork material with the grinding | polishing belt of a belt sander. It is a side view which shows the state which grinds woodworking material with the grinding | polishing belt in FIG.

  Hereinafter, a multi-axis NC woodworking lathe system according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view showing a schematic configuration of a 4-axis NC woodworking lathe used in a multi-axis NC woodworking lathe system.

  A multi-axis NC woodworking lathe system 1 according to the present embodiment includes a chuck 11 for chucking and turning a woodworking material W on a base plate of a 4-axis NC woodworking lathe 10 and a woodworking material W as shown in FIG. The disk-type rotary tool 20 and the spherical rotary tool 31 for cutting are provided. That is, the disk-type rotary tool 20 and the spherical rotary tool 31 are provided on the same stage.

  The chuck 11 includes a C-axis that is a pivot that can chuck the woodwork material W and control the pivot angle.

  The disk-type rotary tool 20 is a disk-type rotary tool having a saw blade 23 on the outer periphery, and a tip saw is used in this embodiment. Further, in order to cut the woodworking material W turning around the C-axis, the disk-type rotary tool 20 is configured to be movable in the Z-axis direction on the extension line of the C-axis and the X-axis direction orthogonal to the Z-axis. Has been. In the present embodiment, the X axis is substantially parallel to the surface of the base plate.

  The spherical rotary tool 31 is a spherical rotary tool provided with a spherical or hemispherical cutter at the tip. Further, in order to cut the woodworking material W that turns around the C axis, the woodworking material W can be moved in the Z axis direction and the X axis direction, and can be turned around the B axis perpendicular to the XZ plane. In the present embodiment, the spherical rotary tool 31 uses a spherical woodworking ball bit with a spherical tip, but it may be a hemispherical woodworking router bit with a tip or other forms.

  In the present embodiment, the B-axis is a Y-axis direction orthogonal to the XZ plane as shown in FIG. 1 and is a rotation axis supported by a mechanical rotation mechanism.

  In the present embodiment, the woodworking material W chucked on the C axis and turning is cut into a three-dimensional product using the disk-type rotary tool 20 and the spherical rotary tool 31 described above. For this purpose, a tool path of the disk-type rotary tool 20 and a tool path of the spherical rotary tool 31 are generated in advance and programmed in the computer.

  The tool path generation method of the present embodiment includes a first tool path generation method necessary for three-dimensional machining using the disk-type rotary tool 20 and a second tool required for three-dimensional machining using the spherical rotary tool 31. And a route generation method.

  First, a three-dimensional shape model 2 in which the surface of the three-dimensional shape of a product is divided into triangles is input to a computer. In the present embodiment, a 3D model in the STL file format is used as the three-dimensional shape model 2. Next, it is assumed that the three-dimensional shape model 2 of the product input to the computer is chucked on the C-axis of the 4-axis NC woodworking lathe 10. Note that the three-dimensional shape model 2 at this time has protrusions such as a doll's nose and ears as shown in FIG.

A first tool path generation method, that is, a tool path generation method of the disk-type rotary tool 20 will be described with reference to the drawings.
FIG. 2A shows a state in which the three-dimensional shape model 2 is virtually chucked on the C axis and a virtual thin disk 21 having the same shape as the disk-type rotary tool 20. The virtual thin disk 21 in FIG. 2A is a thin disk having the same diameter and diameter as the disk-type rotary tool 20.

  In the first tool path generation method, in order to obtain the tool path of the disk-type rotary tool 20, first, the side surface on the chuck 11 side of the virtual thin disk 21 is the left end in FIG. On the Z coordinate. Furthermore, the outer peripheral surface of the virtual thin disk 21 is in a position in contact with the Z axis on the extension line of the C axis. With this state as a starting point, the robot moves in the −Z-axis direction obliquely upward to the right in FIG. 2A while maintaining a state in contact with the turning three-dimensional shape model 2.

  The locus of the contact point between the virtual thin disk 21 and the three-dimensional shape model 2 is drawn spirally on the surface of the virtual three-dimensional shape model 2. At this time, the virtual thin disk 21 moves in the X-axis direction due to the unevenness of the three-dimensional shape model 2. In this moving operation, the disk-type rotary tool 20 is obtained by obtaining the X coordinate of the rotation center of the virtual thin disk 21 according to the arbitrary turning angle θ of the C axis and the arbitrary Z coordinate of the outer periphery of the virtual thin disk 21. This is the tool path.

  More specifically, FIG. 3 shows the geometry of the virtual thin disk 21 and the triangles on the surface of the three-dimensional shape model 2 located in the space region 22 of the virtual thin disk 21 between the planes including both side surfaces thereof. It shows the physical relationship. Originally, it is necessary to illustrate all the triangles existing in the space region 22 of the virtual thin disk 21 as candidates for contact with the virtual thin disk 21, but in order to make the explanation easy to understand, any two adjacent triangles Is assumed.

  In general, as shown in FIG. 4, in the XY plane formed by the X axis and the Y axis perpendicular to the XZ plane, the center of a circle passing through an arbitrary point A among circles having a radius Rc centered on the X axis. The X coordinate is obtained as an intersection of a circle having a radius Rc centered on the point A and the X axis. With this concept, as shown in FIG. 2B when the chuck 11 side is viewed from the diagonally lower left side in FIG. 2A, with respect to the contact point A between the surface of the three-dimensional shape model 2 and the virtual thin disk 21 The X coordinate of the center of the virtual thin disk 21 can be obtained.

  The tool path of the disk-type rotary tool 20 is obtained by obtaining the X coordinate of the center of the virtual thin disk 21 when in contact with the three-dimensional shape model 2 turning around the C axis by the above method.

  In FIG. 3, a circle having the same radius as the radius of the imaginary thin disk 21 around the intersection C1, C2, C5 of the first plane 22a, which is a plane including the left side surface 21a, and the sides of the triangle is defined as the first plane 22a. Draw on top. Of the intersections where these circles intersect the X axis, the X coordinate of the intersection farthest from the C axis of the turning axis is taken as the X coordinate of the first tool center.

  Next, a second circle having the same radius as that of the virtual thin disk 21 is centered on the intersections C3, C4 and C6 of the second plane 22b, which is a plane including the right side surface 21b in FIG. Draw on the plane 22b. Of the intersections where these circles intersect the X axis, the X coordinate of the intersection farthest from the C axis of the turning axis is taken as the X coordinate of the second tool center.

  Further, with respect to the apex of the triangle in FIG. 3, the apex that may contact the virtual thin disk 21 is located in the space region 22 of the virtual thin disk 21 between the first plane 22a and the second plane 22b. Vertices P2 and P4. Therefore, a circle having the same radius as that of the virtual thin disk 21 is drawn in parallel with the first plane 22a and the second plane 22b with the vertices P2 and P4 as the center. Of the intersections where these circles intersect the X axis, the X coordinate of the intersection farthest from the C axis of the turning axis is taken as the X coordinate of the third tool center.

  Of the X coordinates of the first tool center, the second tool center, and the third tool center obtained as described above, the X coordinate of the intersection farthest from the C axis of the turning axis is the virtual thin disk to be obtained. 21 is the X coordinate of the center of 21 and becomes the tool path of the disk-type rotary tool 20.

  The calculation of the tool path of the virtual thin disk 21 is performed from the tip of the three-dimensional shape model 2 to the end of machining for each turning angle θ and for each feed in the Z-axis direction. The X coordinate of the center of the virtual thin disk 21 when circumscribing the three-dimensional shape model 2 is obtained. The tool path of the disk-type rotary tool 20 is obtained by storing the result together with the G code in a computer.

Next, a second tool path generation method, that is, a tool path generation method of the spherical rotary tool 31 will be described with reference to the drawings.
FIG. 2A shows a virtual sphere 32 having the same diameter as the sphere at the tip of the spherical rotary tool 31. The virtual sphere 32 has the same axis as the rotation axis of the spherical rotary tool 31.

  In the second tool path generation method, in order to obtain the tool path of the spherical rotary tool 31, first, the surface of the virtual sphere 32 is on the Z coordinate of the left end in FIG. 2A of the three-dimensional shape model 2. is there. Further, the axis of the spherical rotary tool 31 coincides with the Z axis. Starting from this state, moving in the XZ plane while maintaining a state of being in contact with the turning three-dimensional shape model 2 while always facing an arbitrary point Zh on the Z axis, It turns around the B axis orthogonal to the XZ plane. Furthermore, in FIG. 2 (a), it moves in the −Z-axis direction.

  The locus of the contact point between the virtual sphere 32 and the three-dimensional shape model 2 is drawn spirally on the surface of the three-dimensional shape model 2. At that time, the spherical rotary tool 31 moves according to the unevenness of the three-dimensional shape model 2 while turning (swinging) around the B axis as described above. In this moving operation, the X and Z coordinates of the center of the virtual sphere 32 are obtained with respect to an arbitrary turning angle θ of the C axis and an arbitrary turning angle α of the rotation axis of the spherical rotary tool 31 with respect to the Z axis. It becomes the tool path of the spherical rotary tool 31.

Image behavior during processing, as shown in FIG. 5 (a), during turning woodworking material W is in the C-axis, the spherical rotary tool 31 having a spherical 32 tip radius r _b is any on the Z-axis Turn (swing) around the B axis while facing the point Zh. For example, the turning angle α is in the range of 0 to 90 °. At this time, the spherical rotary tool 31 repeats reciprocating motion in the r direction by combining the X axis direction and the Z axis direction according to the unevenness of the surface of the virtual three-dimensional shape model 2. In FIG. 5A, the surface of the three-dimensional shape model 2 is processed to be uneven while being translated in the leftward -Z-axis direction.
The arbitrary point Zh on the Z axis is the Z coordinate of the center of the bottom surface when the tip of the product shape is approximated to a hemisphere as shown in FIG. The rear end of the product shape is a cylindrical body connected to the hemisphere of the tip.

  The calculation method of the CAM software on the premise of the above machining operation is that the spherical rotary tool 31 is rotated only by the turning angle α around the B axis with respect to the virtual three-dimensional shape model 2 turned around the C axis by the turning angle θ. The distance Zc in the r direction in the turning state is obtained. This calculation will be repeated. At this time, coordinate conversion is used to easily obtain the center coordinates of the virtual sphere 32 of the spherical rotary tool 31.

That is, the three-dimensional shape model 2 is rotationally converted around the C axis by the same turning angle as the turning angle θ. Further, the three-dimensional shape model 2 and the spherical rotary tool 31 are simultaneously translated by −Zh on the Z axis, and rotated and converted in the opposite direction around the Y axis by the same turning angle as the turning angle α.
As a result, as shown in FIG. 5 (b), schematically in a state for obtaining the just center position of the virtual sphere 32 of radius r _b having a center on the Z-axis position in contact with the triangle of the three-dimensional shape model 2 of the surface Can be

Figure 6 is a three-dimensional shape model 2, the rotation axis of the spherical rotary tool 31 shows a state where the rotary shaft is rotated converted to match on the Z axis, and the virtual sphere 32, the outer circumference of the radius r _b The geometrical positional relationship between a space region 33 in a cylinder obtained by extending a circle in the Z-axis direction and a triangle on the surface of the three-dimensional shape model 2 located in the space region 33 is shown. Candidates that come into contact with the virtual sphere 32 are triangles that exist in the space region 33. All candidates that the surface of the virtual sphere 32 is considered to contact with these triangles are extracted, and only one processing point that should actually contribute to the processing is selected from these candidates.

  As all possible candidates, the first processing point when the surface of the virtual sphere 32 and the vertexes of the triangles constituting the three-dimensional shape model 2 are in contact with each corresponding triangle is extracted. Next, a second processing point is extracted when the surface of the virtual sphere 32 is in contact with the triangle sides constituting the three-dimensional shape model 2. Further, a third processing point is extracted when the surface of the virtual sphere 32 and the triangular plane constituting the three-dimensional shape model 2 are in contact with each other.

  Extract only one machining point that should contribute to actual machining from the three first machining points, second machining points, and third machining point candidates for all triangles obtained as described above. As a result, the X coordinate and Z coordinate of the center of the virtual sphere 32 are obtained.

  Next, a calculation method using a basic equation for obtaining the X coordinate and Z coordinate of the center of the virtual sphere 32 at the first machining point, the second machining point, and the third machining point will be described.

First, the definition of the coordinate system in the present embodiment will be described with reference to FIG.
The rotation axis of the three-dimensional shape model 2 that turns around the C axis by the chuck 11 is defined as the Z axis, and the direction away from the chuck 11 is defined as + Z. In the XZ plane formed by the Z axis and the X axis orthogonal to the Z axis, the direction in which the virtual thin disk 21 is far away is defined as + X. The axis perpendicular to the XZ plane is defined as the Y axis, and the direction in which the screw advances when the right screw is rotated from the + Z axis to the + X axis is defined as + Y. That is, the front side of the paper surface is + Y on the Y axis perpendicular to the intersection of the X axis and the Z axis on the paper surface in FIG. In addition, a turning angle between the Z axis and the rotation axis r of the spherical rotary tool 31 is α. The turning angle around the C axis of the three-dimensional shape model 2 is θ, and the direction in which the three-dimensional shape model 2 is turned clockwise toward the chuck 11 is + θ.

A calculation method for obtaining the center coordinates of the virtual sphere 32 at the first processing point will be described. That is, the center coordinates of the sphere 32 when the surface of the virtual sphere 32 having the center on the Z axis and the apex of the triangle constituting the three-dimensional shape model 2 contact each other.
As shown in FIG. 7, the vertices of the triangle are arbitrary points P (x _p , y _p , z _p ) in the space. The radius of the sphere 32 is set to _{r b.} The Z coordinate Z _C of the center of the sphere 32 can be obtained by Expression (1).

A calculation method for obtaining the center coordinates of the virtual sphere 32 at the second processing point will be described. That is, the center coordinates of the sphere 32 when the surface of the virtual sphere 32 having the center on the Z axis and the sides of the triangle constituting the three-dimensional shape model 2 contact each other.
As shown in FIG. 8, the side of the triangle passes through the point A (x ₁ , y ₁ , z ₁ ) and is a straight line g having a direction cosine of (l, m, n). The radius of the sphere 32 is set to _{r b.} The Z coordinate Z _C of the center of the sphere 32 can be obtained by Expression (2).

A calculation method for obtaining the center coordinates of the virtual sphere 32 at the third processing point will be described. That is, the center coordinates of the sphere 32 when the surface of the virtual sphere 32 having the center on the Z axis and the triangular plane constituting the three-dimensional shape model 2 are in contact with each other.
As shown in FIG. 9, the triangular plane has a point P ₁ (x ₁ , y ₁ , z ₁ ), a point P ₂ (x ₂ , y ₂ , z ₂ ), a point P ₃ (x ₃ , y ₃ , z ₃ ), π is a plane passing through. The radius of the sphere 32 is set to _{r b.} The Z coordinate Z _C of the center of the sphere 32 can be obtained by Expression (3).

In the equations (1), (2), and (3) as described above, two solutions (Z _C1 and Z _C2 ) of ± are obtained. For example, in FIG. 7, a solution of two spheres 32 and 32 in contact with the vertex P is obtained. In FIG. 8, the solutions of the two spheres 32 and 32 in contact with the point P ₀ and the point Q ₀ on the straight line g are obtained. In Figure 9, the solution of the two spheres 32, 32 in contact with the point of the triangular planes [pi _{Q 1} and point _{Q 2} is obtained. However, only one of them is actually used.

Therefore, as the first processing point, a Z coordinate group of the center of the sphere 32 when the surface of the virtual sphere 32 and the apex of the triangle constituting the three-dimensional shape model 2 are in contact with each other is obtained. As the second processing point, a Z coordinate group of the center of the sphere 32 when the surface of the virtual sphere 32 and the sides of the triangle constituting the three-dimensional shape model 2 are in contact is obtained. Furthermore, as a third processing point, a Z coordinate group of the center of the sphere 32 when the surface of the virtual sphere 32 and the triangular plane constituting the three-dimensional shape model 2 are in contact with each other is obtained.
Among these all Z coordinate groups, the Z coordinate farthest from Z = Zh is adopted as the tool path on the Z axis of the spherical rotary tool 31.
The adopted Z coordinate on the Z-axis is obtained by turning in the positive direction by the turning angle α around the point Z = Zh and converting the rotational coordinate to obtain the X coordinate and the Z coordinate. It becomes.

  The calculation of the tool path of the spherical rotary tool 31 is performed from the tip of the three-dimensional shape model 2 to the end of machining at every turning angle θ and every feed in the Z-axis direction, and the surface of the virtual sphere 32 is tertiary. The X coordinate and Z coordinate of the center of the virtual sphere 32 when circumscribing the original shape model 2 are obtained. The tool path of the spherical rotary tool 31 is obtained by storing the result together with the G code in the computer.

  As described above, the multi-axis NC woodworking lathe system 1 according to the embodiment of the present invention has a three-dimensional shape model 2 of a product that is chucked on the C-axis and is turning and divided into triangles and input to a computer. The tool path of the disk-type rotary tool 20 can be generated in advance by the virtual thin disk 21 in contact therewith. With this tool path, the actual disk-type rotary tool 20 can roughly cut a three-dimensional product from the woodworking material W within one feed operation in a time efficient manner.

Next, the tool path of the spherical rotary tool 31 can be generated in advance by the virtual sphere 32 in contact with the three-dimensional shape model 2. By using this tool path, a fine portion in the three-dimensional product can be efficiently cut in a short time using an actual spherical rotary tool 31 on the same stage as the disk-type rotary tool 20 immediately without removing the material. can do.
Even if the spherical rotary tool 31 is provided on the same stage as the disk-type rotary tool 20, if the spherical rotary tool 31 simply moves in the X-axis direction and the Z-axis direction, it cannot perform fine unevenness processing. In this embodiment, since the spherical rotary tool 31 is swung around the B axis, it is possible to effectively perform fine uneven processing continuously from the end face to the side face of the material. It has become.

  As described above, according to the present embodiment, it is inexpensive and does not require complicated and expensive hardware and software, and three-dimensional processing with a lathe is efficiently performed in a short time including fine uneven processing. It is possible.

  In the multi-axis NC woodworking lathe system 1 of the above-described embodiment, the three-dimensional shape model 2 has been described using a three-dimensional product whose surface is divided by a triangle. As an example, a 3D model in the STL file format was used. However, the three-dimensional shape model 2 is not limited to this, and can be applied to, for example, the three-dimensional shape model 2 of a product whose surface is divided into polygon polygons having a three-dimensional curved surface. That is, it is a three-dimensional shape model 2 of a product whose surface is represented entirely or partially by a curved surface function. For example, a function expression form of a free-form surface such as NURBS used in general CAM software such as an automobile or a mold can be included.

It can be assumed that the surface of the three-dimensional shape model 2 in this case is divided into triangles in which the vertices on the curved surface of the polygon polygon are connected by a straight line. For example, as shown in FIG. 10 (a), assuming that an arbitrary Z coordinate of the three-dimensional shape model 2 is sliced on the extension of both side surfaces of the tip saw 20 (disk-shaped rotary tool), FIG. The slice piece 2a as shown is taken out. The three-dimensional curved surface of the slice piece 2a is divided into three-dimensional curved polygons. Since each polygon polygon has a vertex on the curved surface, if the vertices of adjacent polygon polygons are connected by a straight line, it can be assumed that the surface is divided into triangles as shown in FIG. it can. That is, as in the above-described embodiment, the form is the same as the three-dimensional shape model 2 of the product whose surface is divided into triangles.
Therefore, a processing point can be obtained for the above-described divided triangles in the same manner as in the above-described embodiment even for the product three-dimensional shape model 2 whose surface is divided into polygon polygons having a three-dimensional curved surface. it can.

It can be assumed that the surface of the three-dimensional shape model 2 in this case is divided into triangles in which the vertices on the curved surface of the polygon polygon are connected by a straight line. For example, as shown in FIG. 10 (a), assuming that an arbitrary Z coordinate of the three-dimensional shape model 2 is sliced on the extension of both side surfaces of the tip saw 20 (disk-shaped rotary tool), FIG. The slice piece 2a as shown is taken out. The surface of the three-dimensional curved surface of the slice piece 2a may be a curved surface that is entirely represented by a single function, or may be a polygon that is partially represented by a function. If there are vertices on the curved surface and the vertices are connected by a straight line, it can be assumed that the curved surface is divided into triangles as shown in FIG. That is, as in the above-described embodiment, the form is the same as the three-dimensional shape model 2 of the product whose surface is divided into triangles. However, it is assumed that the deviation between the triangular plane and the function of the curved surface representing the three-dimensional model 2 exists to the extent that does not cause a problem in practice.
Therefore, a processing point can be obtained for the above-described divided triangles in the same manner as in the above-described embodiment even for the product three-dimensional shape model 2 whose surface is divided into polygon polygons having a three-dimensional curved surface. it can.

Next, a machining system that can be further added to the multi-axis NC woodworking lathe system 1 of the above-described embodiment will be described.
The disk-type rotary tool 20 moves in the Z-axis direction while maintaining the state in which the outer peripheral saw blade 23 is always in contact with the turning three-dimensional shape model 2, and has a new function. That is, the disk-type rotary tool 20 is controlled so as to be directed in a direction perpendicular to the surface of the three-dimensional shape model 2, that is, a normal direction.
The disc-shaped rotary tool 20 is movable in the Z-axis direction and the X-axis direction orthogonal to the Z-axis in FIGS. 10 (a), 11 and 12. Further, it can pass around the center of rotation of the disk-type rotary tool 20 and can turn around the D axis perpendicular to the XZ plane.

In order to obtain the tool path of the disk-type rotary tool 20, the outer periphery of the virtual thin disk 21 moves in the Z-axis direction while maintaining the state in contact with the three-dimensional shape model 2 that is turning, It is assumed that the direction of the virtual thin disk 21 is directed perpendicular (normal direction) to the surface of the three-dimensional shape model 2.
As shown in FIGS. 12, 13, and 14, at an arbitrary Z coordinate Zi, and a turning angle θi of the C axis, a straight line perpendicular to the Z axis in the XZ plane and parallel to the X axis, and the three-dimensional shape model 2 Let P (Xi, θi, Zi) be the intersection with the surface. The intersection point P is a point where the outer periphery of the virtual thin disk 21 is scheduled to come into contact with the surface of the three-dimensional shape model 2 perpendicularly.
A normal vector POc of radius Rc of the thin disk 21 whose length is virtual is calculated from the intersection point P in the normal direction. Let H be the foot of a perpendicular line (ie, the intersection with the Z axis) from the tip position Oc of the normal vector POc to the Z axis, and let Xc be the length of HOc. At this time, a rotation angle obtained by rotating the three-dimensional shape model 2 around the Z axis until HOc coincides with the XZ plane is denoted by γ. At this time, the angle formed by the projection vector POc ′ of the normal vector POc on the XZ plane and the X axis is β, and the X coordinate of the center of the virtual thin disk 21 is Xc.

Therefore, with respect to the intersection P (Xi, θi, Zi), the X coordinate Xc of the center position of the virtual thin disk 21 and the X axis, which are necessary for processing by the virtual thin disk 21 from the normal direction. The formed angle β and the rotation angle γ of the three-dimensional shape model 2 can be obtained.
The Z coordinate Zc of the center 21c of the virtual thin disk 21 can be calculated from the vector HOc and the angle γ by rotational coordinate conversion.

  When the shape of the three-dimensional shape model 2 is expressed by a function of a free-form surface such as NURBS, the normal vector at the intersection point P is, for example, Reference 1 [Hagano, Shamoto, Moriwaki: Tool path by the direct offset method. It can be obtained from the coordinate value of the intersection P by the method of generation (first report), Japan Society for Precision Engineering, Vol.69, No.6, 2003].

  In the disk-type rotary tool 20 of this embodiment, even when the three-dimensional shape model 2 is a three-dimensional product whose surface is divided into triangles, or the surface is divided into polygonal polygons with a three-dimensional curved surface. Also in the case of a product, a processing point can be obtained for a triangle whose surface is divided as in the above-described embodiment.

  From the above, for example, assuming that the rotation angle of the three-dimensional shape model 2 is Δθ and the amount of movement in the −Z direction of the intersection P per one rotation of the three-dimensional shape model 2 is ΔZ, the surface of the three-dimensional shape model 2 And the intersection P of the X axis is determined in a spiral shape as shown in FIG. The disk-type rotary tool 20 can be cut while always facing the normal direction while swinging with respect to the spiral machining point. As a result, the surface roughness due to the spiral cutter mark by the edge of the disk-type rotary tool 20 is reduced. That is, the roughness of the processed surface is reduced and a processed surface corresponding to the polished surface is obtained, so that the time for the polishing process can be shortened.

Next, processing systems that can be further added in the above embodiment will be described.
In the above embodiment, the disk-type rotary tool 20 is controlled so as to face the normal direction with respect to the surface of the three-dimensional shape model 2. However, when the three-dimensional shape model 2 has a shape with a large dent 2b as shown in FIG. 15, for example, the disk-type rotary tool 20 and the three-dimensional shape model 2 interfere with each other as shown by the oblique lines in FIG. Problems arise.

  Therefore, in order to solve the above problem, the virtual thin disk 21 is defined by a tool coordinate system including a large number of points around the surface. Next, it is assumed that the virtual thin disk 21 is swung by an angle β in order to orient the virtual thin disk 21 in a direction perpendicular to the surface of the three-dimensional shape model 2, that is, a normal direction. At this time, if at least one of the many points defined in the tool coordinate system is inside the three-dimensional shape model 2, it is determined that the virtual thin disk 21 has interfered with the three-dimensional shape model 2. be able to.

  As described above, as a method for determining whether or not the tool and the material interfere with each other, the method described in Reference 2 [Takeuchi: 5-axis control machining based on solid model, Journal of Precision Engineering, 56, 11, (1990), 2063] is used. Can be implemented. This method is a method for determining whether or not all points are inside the machining shape in the process of converting the tool surface into a set of points and calculating the tool path.

When it is determined that the virtual thin disk 21 has interfered with the three-dimensional shape model 2, the orientation of the virtual thin disk 21 is swung by an angle β-90 ° as shown in FIG. As a result, the virtual thin disk 21 is directed tangential to the surface of the three-dimensional shape model 2.
Next, the tip of the virtual thin disk 21 is positioned so as to contact the processing point of the three-dimensional shape model 2. As the disk-type rotary tool 20, for example, a tip saw 20 provided with a bee-shaped tip 20a (cutting blade) is used. The position of the tip saw 20 is determined so as to come into contact with the processing point at a position within the range of the length of the side surface of the chip 20a, for example, at an intermediate point of the chip length.

  From the above, since the disk-type rotary tool 20 is cut in the tangential direction so as not to interfere with the three-dimensional shape model 2, the surface roughness due to the spiral cutter mark by the edge of the disk-type rotary tool 20 is reduced. . That is, the roughness of the processed surface is reduced and a processed surface corresponding to the polished surface is obtained, so that the time for the polishing process can be shortened.

  In addition, when the disk-type rotary tool 20 is switched between the normal direction and the tangential direction every time the wood-work material W is rotated in the C-axis direction during the cutting of the woodwork material W, the swing or processing of the disk-type rotary tool 20 is performed. Since positioning to a point is frequently performed, processing time is wasted. In order to solve this problem, an area that can be processed in the normal direction and an area that can be processed in the tangential direction can be divided and processed separately.

Next, a machining system that can be further added to the multi-axis NC woodworking lathe system 1 of the above-described embodiment will be described.
This machining system basically uses a band saw blade in advance for the cutting allowance between the square outer shape of the woodworking material W and the contour of the 3D shape, for example, when a 3D shape is cut out from the woodworking material W of a square. It is intended to remove in a short time with less energy by cutting off as a lump using No. 23.

  As shown in FIG. 17, the four-axis NC woodworking lathe 10 of the present embodiment further includes a band saw 40 having a band saw blade 41 that travels in parallel with a direction orthogonal to the C axis. The band saw blade 41 is wound endlessly between the two drive wheels 42 and the driven wheel 43, and is rotated by the drive wheel 42. The two wheels 42 and 43 are arranged on the upper side of the woodworking material W in order to avoid interference with the bed and chuck 11 of the 4-axis NC woodworking lathe 10. Further, the band saw 40 is configured to be rotatable in the direction around the A axis connecting the rotation centers of the two wheels 42 and 43.

Further, in the present embodiment, the band saw blade 41 is movable as a whole in the Z-axis direction parallel to the Z-axis and the F-direction orthogonal to the Z-axis, and the direction of the band saw blade 41 is changed with respect to the Z-axis direction. Can be changed to be inclined. This turning is performed by rotating the two wheels 42 and 43 in the direction around the A axis.
In this embodiment, the F direction corresponds to the Y direction as shown in FIG. 17, but is not limited to this Y direction. That is, the band saw blade 41 may be movable as a whole in the Z-axis direction and the X direction orthogonal to the Z axis, or may be in any other direction as long as the direction is orthogonal to the Z axis. That is, the installation state of the band saw machine 40 is not limited to one direction in which the band saw blade 41 moves in the Z-axis direction as a whole and moves toward and away from the Z-axis, and can be arbitrarily set.

  In order to obtain the tool path of the band saw blade 41 of the band saw machine 40, the turning angle θ of the C axis of the three-dimensional shape model 2 chucked on the C axis is set to zero degree (0 °). That is, when the virtual band saw tool 44 having the same shape as the band saw blade 41 slices the three-dimensional shape model 2 in the Z axis direction parallel to the Z axis in a state where the turning around the C axis is stopped, It is assumed to move in the F direction perpendicular to the Z axis.

  Furthermore, as shown in FIG. 18, a large number of virtual slice sections 2c parallel to the XY plane are formed at appropriate intervals in the three-dimensional shape model 2 in the Z-axis direction, and the maximum points in the + F direction in each virtual slice section 2c Fmax and minimum point Fmin are calculated. In the present embodiment, the maximum point Ymax and the minimum point Ymin in the + Y direction are calculated in each virtual slice section 2c.

  Next, the maximum contour 3 connecting the Ymax (Fmax) and the minimum contour 4 connecting the Ymin (Fmin) are calculated. For example, as shown in FIG. 19, in the virtual slice sections 2c, 2c,... Sliced at intervals of 0.1 mm, the maximum contour 3 connects each Ymax (Fmax) with a free curve such as NURBS. It consists of a curve. On the other hand, the minimum part outline 4 is composed of a curve obtained by connecting each Ymin (Fmin) with a free curve such as NURBS.

Next, the maximum part offset line 5 for the maximum part outline 3 and the minimum part offset line 6 for the minimum part outline 4 are calculated.
As a calculation method of the maximum part offset line 5, first, all points of each Fmax in each virtual slice section 2c are interpolated with respect to the maximum part outline 3 by a spline function such as NURBS. A maximum part offset line 5 that is a fixed distance from the interpolated maximum part outline 3 is calculated. The fixed distance can be a distance equal to or less than the length (for example, 2 to 3 mm) of the tip 20a of the tip saw 20, for example.
Next, the intersection of the maximum offset line 5 and the sliced virtual slice section 2c is obtained, and discrete data of points on the maximum offset line 5 is obtained.
The calculation method of the minimum part offset line 6 is basically the same as the calculation method of the maximum part offset line 5, and thus detailed description thereof is omitted.

  At least one of the maximum part offset line 5 and the minimum part offset line 6 obtained as described above can be obtained as a tool path of the virtual band saw tool 44. That is, if it is possible in terms of equipment, without turning the woodworking material W in the C-axis direction, for example, the maximum offset line 5 is used as the tool path of the virtual band saw tool 44, and then the minimum offset line 6 is virtually set. The tool path of the band saw tool 44 can be used. In this case, the cutting efficiency is improved.

  In the above operation, the three-dimensional shape model 2 is turned and stopped at every pitch of the turning angle θ of the C axis, the maximum part contour line 3 and the minimum part contour line 4 are obtained, and the corresponding maximum part offset line 5 and The minimum offset line 6 can be obtained. For example, the rotation is performed at a pitch of 30 ° of the rotation angle of the C axis, and the maximum portion contour line 3 and the minimum portion contour line 4 with respect to each turning angle θ are obtained. Next, the maximum offset line 5 and the minimum offset line 6 corresponding to each are obtained.

In the present embodiment, the band saw machine 40 is arranged so that the band saw blade 41 travels in parallel with the direction orthogonal to the C axis, as shown in FIG. 17 described above.
The band saw blade 41 cuts along the maximum part offset line 5 among the two maximum part offset lines 5 and minimum part offset lines 6 obtained by turning the three-dimensional shape model 2 for each turning angle θ of the C axis. . The tip of the band saw blade 41 moves between points on the maximum offset line 5, and the band saw blade 41 cuts the woodworking material W while facing the tangential direction of the offset line.

  Note that the band saw blade 41 has a narrow width, for example, 5 mm as shown in FIG. 21, in order to cut the woodworking material W into a curved shape. At this time, the blade tip 41c having a thickness A of 1 mm and a base metal 41b having a thickness B of 0.5 mm is used. However, when cutting the woodworking material W with a curve having a small radius of curvature R, the cutting groove 45 of the woodworking material W and the band saw blade 41 may interfere with each other. For example, as shown in FIG. 21, as a result of drawing and measuring with the above dimensions, when cutting along the curve of the maximum offset line 5 using the band saw blade 41, the curvature radius R that becomes a limit is It is about 49 mm. Therefore, in this example, the maximum part offset line 5 and the minimum part offset line 6 having a radius of curvature R of 49 mm or more are targeted.

Next, a series of operations for cutting a three-dimensional shape from the woodworking material W will be described with respect to the action of the multi-axis NC woodworking lathe system 1 to which the band saw 40 described above is added.
First, in FIG. 22 (a), a square-shaped woodworking material W is chucked on the C-axis, and the slit 24 is cut in advance by the disk-type rotary tool 20 at the position of the cutting end by the band saw blade 41 while turning the C-axis. Put in.

  Next, in FIG. 22B, the tool path of the band saw blade 41 of the band saw machine 40 is obtained in advance by a virtual band saw tool 44 having the same shape as the band saw blade 41. With the swivel angle θ of the C axis being zero degrees (0 °), the band saw blade 41 moves based on the tool path, and the cutting allowance between the square outline of the woodworking material W and the outline of the three-dimensional shape is reduced. Cut off.

  Next, in FIG.22 (c), the woodworking material W stops turning for every pitch of the turning angle (theta) of C axis | shaft, The band saw blade 41 moves based on the said tool path | route, and the external shape and three-dimensional shape of the woodworking material W are shown. Cut off the cutting allowance between the contours of. As a result, most of the cutting allowance between the outer shape of the woodworking material W and the contour of the three-dimensional shape is cut off in a short time with less energy.

Next, in FIG. 22 (d), the tool path of the disk-type rotary tool 20 is obtained in advance by a virtual thin disk 21. The disk-type rotary tool 20 moves based on the tool path, and cuts the remaining three-dimensional contour. At this time, the disk-type rotary tool 20 is controlled so as to be oriented in the normal direction with respect to the surface of the three-dimensional shape model 2, so that it is cut while swinging. Further, the disc-shaped rotary tool 20 is controlled so as to be directed in the tangential direction with respect to the contour of the three-dimensional shape so as not to interfere with the woodworking material W. As a result, the contour of the three-dimensional shape becomes a processed surface corresponding to the polished surface, and thus the time for the polishing process is shortened.
Although not shown, the tool path of the spherical rotary tool 31 is obtained in advance by a virtual sphere 32 having the tip shape of a sphere having the same diameter as the spherical rotary tool 31. The spherical rotary tool 31 moves based on the tool path and cuts the remaining portion of the three-dimensional contour.

Next, a machining system that can be further added to the multi-axis NC woodworking lathe system 1 of the above-described embodiment will be described.
This processing system automatically grinds the contour of the three-dimensional shape with the polishing belt 51 after cutting out the three-dimensional shape from the woodworking material W using the disk-type rotary tool 20 or the spherical rotary tool 31. Therefore, the purpose is to shorten the time of the polishing process and to save labor.

  As shown in FIG. 23, the four-axis NC woodworking lathe 10 of this embodiment further includes a belt sander 50 having a polishing belt 51 that travels in parallel with a direction orthogonal to the C-axis. The polishing belt 51 is wound endlessly between the two drive wheels 52 and the driven wheel 53, and is rotated by the drive wheel 52. The belt sander 50 is configured to be rotatable in the direction around the B axis connecting the rotation centers of the two wheels 52 and 53.

In this embodiment, the polishing belt 51 is movable as a whole in the Z-axis direction parallel to the Z-axis and the F-direction orthogonal to the Z-axis, and the direction of the polishing belt 51 is relative to the Z-axis direction. Can be changed to be inclined. This turning is performed by rotating the two wheels 52 and 53 around the B axis.
The F direction corresponds to the X direction as shown in FIG. 23 in the present embodiment as described in the band saw blade 41 described above, but is not limited to this X direction. That is, the polishing belt 51 as a whole may be movable in the Z-axis direction and the Y-direction orthogonal to the Z-axis, or may be in any other direction as long as the direction is orthogonal to the Z-axis. That is, the installation state of the belt sander 50 is not limited to one direction in which the polishing belt 51 moves in the Z-axis direction as a whole and moves toward and away from the Z-axis, and can be arbitrarily set.

  In order to obtain the tool path of the polishing belt 51 of the belt sander 50, the turning angle θ of the C axis of the three-dimensional shape model 2 chucked on the C axis is set to zero degree (0 °). That is, the virtual polishing tool 54 having the same shape as the polishing belt 51 moves in the Z-axis direction and the F-direction orthogonal to the Z-axis when polishing the three-dimensional shape model 2 with the rotation around the C-axis stopped. Assuming that

Further, in the band saw machine 40 described above, as shown in FIG. 18, a large number of virtual slice sections 2 c parallel to the XY plane are formed at appropriate intervals with the three-dimensional shape model 2 directed in the Z-axis direction, In the virtual slice section 2c, the maximum point Fmax and the minimum point Fmin in the + F direction are calculated. In the present embodiment, the maximum point Xmax and the minimum point Xmin in the + X direction are calculated in each virtual slice section 2c.
Next, the maximum contour line connecting the respective Xmax (Fmax) and the minimum contour line connecting the respective Xmin (Fmin) are calculated.

At least one of the maximum contour and the minimum contour determined as described above can be obtained as the tool path of the virtual polishing tool 54. In other words, if it is possible in terms of equipment, without rotating in the C-axis direction, for example, the maximum contour is used as the tool path of the virtual polishing tool 54, and then the minimum contour is used as the tool of the virtual polishing tool 54. It can be a route. In this case, the polishing efficiency is improved.
Note that the polishing position of the virtual polishing tool 54 can use the tool path obtained when cutting the cutting allowance by the band saw blade 41 described above.

  In the above operation, the three-dimensional shape model 2 can be turned and stopped at every pitch of the turning angle θ of the C axis, and the maximum part outline and the minimum part outline can be obtained. For example, the rotation is performed at a fine pitch such as the rotation angle of the C-axis of 5 °, and the maximum part outline and the minimum part outline for each turning angle θ are obtained.

In the present embodiment, the belt sander 50 is arranged so that the polishing belt 51 travels in parallel with the direction orthogonal to the C axis, as shown in FIGS.
The polishing belt 51 polishes the three-dimensional shape model 2 along the maximum part contour line among the two maximum part contour lines and minimum part contour lines obtained by turning the C-axis at every turning angle θ. The polishing belt 51 moves between points on the maximum contour line, and the polishing surface of the polishing belt 51 is polished so that the surface direction is the same as the tangential direction of the maximum contour line.

  Accordingly, the woodworking material W reduces the swivel angle θ of the C axis so that the polishing belt 51 travels along a spiral tool path with respect to the three-dimensional shape of the woodworking material W that turns. The polishing belt 51 polishes while reciprocating in the X direction according to the processing point of the woodworking material W, and swinging around the B axis according to the inclination of the surface of the woodworking material W.

Note that the belt sander 50 can generate a pressing force of the polishing belt 51 against the surface of the woodworking material W as shown in FIG. For example, the space between the rotation support shaft 52a of the drive wheel 52 and the rotation support shaft 52a of the driven wheel 53 is expanded by a pressing device 55 such as an air silicinda. Thus, the machining point is pressed from the position of the polishing belt 51 when there is no load so that the machining point moves to the inside of the woodworking material W by ΔX. That is, a pressing force using the tension of the polishing belt 51 is generated.
From the above, the multi-axis NC woodworking lathe system 1 of the present embodiment automatically polishes the contour of the processed product with the polishing belt 51 as the finish of the processed product having a three-dimensional shape. Time saving and labor saving.

  The present invention has applicability in the manufacturing and sales industries related to furniture and craft products, interior-related operations, and the like.

1; multi-axis NC woodworking lathe system 2; three-dimensional shape model 2a; slice piece 2b; dent 2c; virtual slice section 3; maximum contour 4; minimum contour 5; maximum offset 6; minimum offset 10; Four-axis NC woodworking lathe 11; Chuck 20; Disk-type rotary tool 20a; Tip 21; Virtual thin disk 21a; Side surface 21b; Side surface 21c;
22; Spatial region (of the virtual thin disk 21)
22a; first plane 22b; second plane 23; saw blade 24; cut 31; spherical rotary tool 32; virtual sphere 33; spatial region (of the spherical rotary tool 31)
40; Band saw machine 41; Band saw blade 41b; Base metal 42; Drive wheel
43; driven wheel 44; virtual band saw tool 45; cutting groove 50; belt sander 51; grinding belt 52; drive wheel 53; driven wheel 54; virtual grinding tool W;

Claims (23)

In order to cut the woodworking material that is chucked on the C-axis that is the swivel axis that can control the swivel angle and swivels around the C-axis,
A disk-type rotary tool movable in the Z-axis direction and the X-axis direction orthogonal to the Z-axis;
Multi-axis NC equipped with a spherical or hemispherical spherical rotary tool installed on the same stage as the disk type rotary tool and capable of moving around the B axis perpendicular to the XZ plane and moving in the XZ plane A woodworking lathe system,
Suppose that the three-dimensional shape model of the product whose surface is divided into triangles and input to the computer is chucked on the C axis,
Assuming that the outer periphery of a virtual thin disk having the same shape as the disk-type rotary tool moves in the Z-axis direction while maintaining a state in contact with the rotating three-dimensional shape model, Obtaining the X coordinate of the center of rotation of the virtual thin disk for an arbitrary turning angle θ and an arbitrary Z coordinate of the outer periphery of the virtual thin disk,
While maintaining the state in which the surface of the virtual sphere having the tip shape of the sphere having the same diameter as the spherical rotary tool is in contact with the three-dimensional shape model turning around the C axis, Assuming that the rotation axis always turns to the arbitrary point Zh on the Z-axis so as to turn around the B-axis,
When obtaining the X and Z coordinates of the center of the sphere with respect to an arbitrary turning angle α formed by an arbitrary turning angle θ of the C axis and a Z axis of the rotating shaft of the spherical rotary tool,
A first processing point when the surface of the sphere and the vertex of the triangle constituting the three-dimensional shape model are in contact with each other, and a second processing point when the surface of the sphere and the side of the triangle constituting the three-dimensional shape model are in contact with each other Machining points that should contribute to actual machining from among the three machining point candidates: machining points and third machining points when the surface of the sphere touches the triangular plane that constitutes the three-dimensional shape model The multi-axis NC woodworking lathe system is characterized in that the X coordinate and Z coordinate of the center of the sphere are obtained by extracting only one of them.   The three-dimensional shape model is a product whose surface is divided into polygon polygons having a three-dimensional curved surface, and has a vertex on the curved surface of the polygon polygon, and the vertex is divided into triangles connected by straight lines. The multi-axis NC woodworking lathe system according to claim 1, which is assumed. The disk-type rotary tool can move in the Z-axis direction and the X-axis direction orthogonal to the Z-axis, and can turn around the D-axis that passes through the center of rotation of the disk-type rotary tool and is perpendicular to the XZ plane. And
The outer circumference of a virtual thin disk having the same shape as the disk-type rotary tool moves in the Z-axis direction while maintaining a state in contact with the three-dimensional shape model that is turning, and the virtual thin disk Assuming that the direction is perpendicular to the surface of the three-dimensional shape model,
From the contact point between the outer periphery of the virtual thin disk and the surface of the three-dimensional shape model, a normal vector whose length in the normal direction is the radius of the virtual thin disk is calculated, and the tip of the normal vector A rotation angle γ obtained by rotating the three-dimensional shape model around the Z axis until a straight line perpendicular to the Z axis from the position coincides with the XZ plane, and a projection component of the normal vector onto the XZ plane forms an X axis. The multi-axis NC according to claim 1 or 2, wherein an X coordinate and a Z coordinate of the center of the virtual thin disk are obtained with respect to an angle β and an arbitrary turning angle θ of the C axis. Woodworking lathe system. The virtual thin disk is defined by a tool coordinate system consisting of a number of points around its surface,
When it is assumed that the virtual thin disk is swung by the angle β in order to orient the perpendicular thin disk in a direction perpendicular to the surface of the three-dimensional shape model, at least one of a plurality of points defined in the tool coordinate system is used. If the point is inside the three-dimensional shape model, it is determined that the virtual thin disk has interfered with the three-dimensional shape model,
The orientation of the virtual thin disk is swung by an angle β-90 °, and the tip of the virtual thin disk is positioned so as to contact the machining point of the three-dimensional shape model. Axis NC woodworking lathe system.   The multi-axis according to any one of claims 1 to 4, wherein the arbitrary point Zh on the Z-axis is a Z coordinate of the center of the bottom surface when the tip of the product shape is approximated to a hemisphere. NC woodworking lathe system.   6. The multi-axis NC woodworking lathe system according to claim 1, wherein the spherical rotary tool is a ball bit for woodworking or a router bit for woodworking at a tip end. In the multi-axis NC woodworking lathe system according to claim 1, 2, or 3,
A band saw blade that runs parallel to the direction perpendicular to the C axis, the band saw blade is movable in the Z axis direction parallel to the Z axis and the F direction perpendicular to the Z axis as a whole, and the band saw blade A band saw machine that can be turned to incline with respect to the Z-axis direction,
When the virtual band saw tool having the same shape as the band saw blade of the band saw machine slices in the Z-axis direction parallel to the Z-axis with respect to the three-dimensional shape model with the C-axis turning angle θ being zero degrees, the Z-axis Assuming movement in the F direction perpendicular to the direction and the Z axis,
A large number of virtual slice sections parallel to the XY plane are formed at appropriate intervals in the Z-axis direction with respect to the three-dimensional shape model, and a maximum point Fmax and a minimum point Fmin in the + F direction are calculated in each virtual slice section. The maximum contour line connecting Fmax and the minimum contour line connecting each Fmin are calculated, and the maximum offset line for the maximum contour line and the minimum offset line for the minimum contour line are calculated. A multi-axis NC woodworking lathe system, wherein at least one of the maximum part offset line and the minimum part offset line is obtained as a tool path of the virtual band saw tool.   The maximum part outline and the minimum part outline are calculated by stopping each time the three-dimensional shape model is rotated at a turning angle θ of an appropriate pitch of the C axis, and each of the maximum part outline and the minimum part outline is calculated. The multi-axis NC woodworking lathe system according to claim 7, which is obtained by calculating a maximum part offset line and a minimum part offset line corresponding to. In the multi-axis NC woodworking lathe system according to claim 1, 2, 3, or 7,
The polishing belt includes a polishing belt that runs parallel to a direction orthogonal to the C-axis, the polishing belt is movable in the Z-axis direction parallel to the Z-axis and the F-direction orthogonal to the Z-axis as a whole, and the polishing belt A belt sander that can be turned so as to be inclined with respect to the Z-axis direction,
When the virtual polishing tool having the same shape as the polishing belt of the belt sander polishes the three-dimensional shape model with the C-axis turning angle θ being zero degrees, the Z direction and the F direction perpendicular to the Z axis On the premise of moving to
A large number of virtual slice sections parallel to the XY plane are formed at appropriate intervals in the Z-axis direction with respect to the three-dimensional shape model, and a maximum point Fmax and a minimum point Fmin in the + F direction are calculated in each virtual slice section. The maximum contour line connecting Fmax and the minimum contour line connecting each Fmin are calculated, and at least one of the maximum contour line and the minimum contour line is used as a tool of the virtual polishing tool. A multi-axis NC woodworking lathe system characterized by being obtained as a path.   10. The maximum part outline and the minimum part outline are obtained by stopping and calculating each time the three-dimensional shape model is rotated at a turning angle θ of an appropriate pitch of the C axis. Multi-axis NC woodworking lathe system. First tool path generation method required for three-dimensional machining using a disk-type rotary tool, and second tool path required for three-dimensional machining using a spherical rotary tool whose tip is a spherical or hemispherical rotary tool A tool path generation method combining the generation method,
Assuming that the three-dimensional shape model of the product whose surface is divided into triangles and input to the computer is chucked to the C axis, which is a pivot axis that can control the pivot angle on a 4-axis NC woodworking lathe,
As a first tool path generation method, an outer periphery of a virtual thin disk having the same shape as the disk-type rotary tool is maintained in contact with the three-dimensional shape model turning around the C axis. Assuming movement in the Z-axis direction, the X-coordinate of the rotation center of the virtual thin disk is obtained with respect to the arbitrary turning angle θ of the C-axis and the arbitrary Z coordinate of the outer periphery of the virtual thin disk. Generate a route,
As a second tool path generation method, a surface of a virtual sphere having a sphere tip shape having the same diameter as the spherical rotary tool is in contact with the three-dimensional shape model turning around the C axis. The center of the sphere is assumed on the premise that the rotary axis of the spherical rotary tool moves in the XZ plane while always turning to an arbitrary point Zh on the Z axis and turns around the B axis perpendicular to the XZ plane. In order to obtain the X coordinate and the Z coordinate, when the arbitrary turning angle θ of the C axis and the arbitrary turning angle α formed by the Z axis of the rotating shaft in the spherical rotary tool are as follows:
Both the three-dimensional shape model and the spherical rotating tool are simultaneously rotated in the opposite direction by the same turning angle as the turning angle α around the straight line passing through the Zh at a right angle to the XZ plane, thereby converting the spherical coordinates. Make the rotation axis of the rotary tool coincide with the Z axis,
The Z coordinate group of the center of the sphere when the surface of the sphere and the apex of the triangle constituting the three-dimensional shape model are in contact with the surface of the sphere and the sides of the triangle constituting the three-dimensional shape model Z coordinate group of the center of the sphere at the time, and the Z coordinate group of the center of the sphere when the surface of the sphere is in contact with the triangular plane constituting the three-dimensional shape model, Among them, the Z coordinate farthest in the + Z direction located outside the three-dimensional shape model from the point Z = Zh is adopted, and the adopted Z coordinate is rotated around the straight line passing through the Zh at right angles to the XZ plane. A tool path generation method characterized in that an X coordinate and a Z coordinate obtained by turning in the positive direction by an angle α and converting rotational coordinates are used as a tool path.   The three-dimensional shape model is a product whose surface is divided into polygon polygons having a three-dimensional curved surface, and has a vertex on the curved surface of the polygon polygon, and the vertex is divided into triangles connected by straight lines. The tool path generation method according to claim 11, which is assumed. As the first tool path generation method, an outer periphery of a virtual thin disk having the same shape as that of the disk-type rotary tool is maintained in contact with the three-dimensional shape model turning around the C axis. Assuming that the direction of the virtual thin disk is oriented perpendicular to the surface of the three-dimensional shape model while moving in the Z-axis direction,
From the contact point between the outer periphery of the virtual thin disk and the surface of the three-dimensional shape model, a normal vector whose length in the normal direction is the radius of the virtual thin disk is calculated, and the tip of the normal vector A rotation angle γ obtained by rotating the three-dimensional shape model around the Z axis until a straight line perpendicular to the Z axis from the position coincides with the XZ plane, and a projection component of the normal vector onto the XZ plane forms an X axis. The tool path generation according to claim 11 or 12, wherein an X coordinate and a Z coordinate of the center of the virtual thin disk are obtained with respect to an angle β and an arbitrary turning angle θ of the C axis. Method. The virtual thin disk is defined by a tool coordinate system consisting of a number of points around its surface,
When it is assumed that the virtual thin disk is swung by the angle β in order to orient the perpendicular thin disk in a direction perpendicular to the surface of the three-dimensional shape model, at least one of a plurality of points defined in the tool coordinate system is used. If the point is inside the three-dimensional shape model, it is determined that the virtual thin disk has interfered with the three-dimensional shape model,
The tool according to claim 13, wherein the direction of the virtual thin disk is swung by an angle β-90 °, and the tip of the virtual thin disk is positioned so as to contact the machining point of the three-dimensional shape model. Route generation method. In the tool path generation method according to any one of claims 11 to 14,
A band saw blade that runs parallel to the direction perpendicular to the C axis, the band saw blade is movable in the Z axis direction parallel to the Z axis and the F direction perpendicular to the Z axis as a whole, and the band saw blade A third tool path generation method necessary for three-dimensional machining using a band saw machine capable of changing the direction of the blade so as to be inclined with respect to the Z-axis direction,
As the third tool path generation method, a virtual band saw tool having the same shape as the band saw blade of the band saw machine is parallel to the Z axis with respect to the three-dimensional shape model with the C axis turning angle θ being zero degrees. When slicing in the Z-axis direction, assuming that the Z-axis direction and the F-direction perpendicular to the Z-axis move,
A large number of virtual slice sections parallel to the XY plane are formed at appropriate intervals in the Z-axis direction with respect to the three-dimensional shape model, and a maximum point Fmax and a minimum point Fmin in the + F direction are calculated in each virtual slice section. The maximum contour line connecting Fmax and the minimum contour line connecting each Fmin are calculated, and the maximum offset line for the maximum contour line and the minimum offset line for the minimum contour line are calculated. And generating a tool path of the virtual band saw tool for at least one of the maximum part offset line and the minimum part offset line. In the tool path generation method according to any one of claims 11 to 15,
The polishing belt includes a polishing belt that runs parallel to a direction orthogonal to the C-axis, the polishing belt is movable in the Z-axis direction parallel to the Z-axis and the F-direction orthogonal to the Z-axis as a whole, and the polishing belt A fourth tool path generation method necessary for three-dimensional machining using a belt sander that can be changed so as to incline the direction of the Z-axis with respect to the Z-axis direction,
As the fourth tool path generation method, when a virtual polishing tool having the same shape as the polishing belt of the belt sander is polished with respect to the three-dimensional shape model in which the turning angle θ of the C axis is zero degrees, On the premise of moving in the Z-axis direction and the F-direction orthogonal to the Z-axis,
A large number of virtual slice sections parallel to the XY plane are formed at appropriate intervals in the Z-axis direction with respect to the three-dimensional shape model, and a maximum point Fmax and a minimum point Fmin in the + F direction are calculated in each virtual slice section. The maximum contour line connecting Fmax and the minimum contour line connecting each Fmin are calculated, and at least one of the maximum contour line and the minimum contour line is used as a tool of the virtual polishing tool. A tool path generation method characterized by generating a path. Assuming that the three-dimensional shape model of the product whose surface is divided into triangles and input to the computer is chucked to the C-axis, which is a turning axis capable of controlling the turning angle on a 4-axis NC woodworking lathe, First tool path generation program necessary for three-dimensional machining using a rotary tool and second tool path generation program necessary for three-dimensional machining using a spherical rotary tool whose tip is a spherical or hemispherical rotary tool And a tool path generation program that combines
The first tool path generation program is:
On the premise that the outer periphery of a virtual thin disk having the same shape as the disk-type rotary tool moves in the Z-axis direction while maintaining a state in contact with the three-dimensional shape model that is turning around the C-axis. The X-axis of the center of rotation of the virtual thin disk is obtained with respect to the arbitrary turning angle θ of the C axis and the arbitrary Z coordinate of the outer periphery of the virtual thin disk, thereby obtaining the tool path of the disk type rotary tool. ,
The second tool path generation program is
While maintaining the state in which the surface of the virtual sphere having the tip shape of the sphere having the same diameter as the spherical rotary tool is in contact with the three-dimensional shape model turning around the C axis, the rotational axis of the spherical rotary tool In order to obtain the X and Z coordinates of the center of the sphere on the assumption that the lens moves in the XZ plane while always facing an arbitrary point Zh on the Z axis and turns around the B axis perpendicular to the XZ plane ,
When an arbitrary swivel angle θ between the arbitrary swivel angle θ of the C axis and the Z axis of the rotation axis of the spherical rotating tool, both the three-dimensional shape model and the spherical rotating tool are simultaneously perpendicular to the XZ plane. The rotational axis of the spherical rotary tool is made to coincide with the Z axis by turning in the reverse direction by the same turning angle as the turning angle α around the straight line passing through the Zh,
The Z coordinate group of the center of the sphere when the surface of the sphere and the apex of the triangle constituting the three-dimensional shape model are in contact with the surface of the sphere and the sides of the triangle constituting the three-dimensional shape model Z coordinate group of the center of the sphere at the time, and the Z coordinate group of the center of the sphere when the surface of the sphere is in contact with the triangular plane constituting the three-dimensional shape model, Among them, the Z coordinate farthest from the point Z = Zh in the + Z direction located outside the three-dimensional shape model is adopted,
The X coordinate and the Z coordinate obtained by turning the adopted Z coordinate in the positive direction by the turning angle α around the straight line passing through the Zh at a right angle to the XZ plane are used as a tool path. Feature tool path generation program.   Assuming that the three-dimensional shape model is a product whose surface is divided into polygon polygons having a three-dimensional curved surface, and has a vertex on the curved surface of the polygon polygon, and the vertex is divided into triangles connected by straight lines. The tool path generation program according to claim 17, wherein: The first tool path generation program is:
The outer periphery of a virtual thin disk having the same shape as that of the disk-type rotary tool moves in the Z-axis direction while maintaining a state in contact with the three-dimensional shape model that is turning around the C axis, and the virtual Assuming that the direction of the thin disk is oriented perpendicularly to the surface of the three-dimensional shape model,
From the contact point between the outer periphery of the virtual thin disk and the surface of the three-dimensional shape model, a normal vector whose length in the normal direction is the radius of the virtual thin disk is calculated, and the tip of the normal vector A rotation angle γ obtained by rotating the three-dimensional shape model around the Z axis until a straight line perpendicular to the Z axis from the position coincides with the XZ plane, and a projection component of the normal vector onto the XZ plane forms an X axis. 19. The tool path generation according to claim 17 or 18, wherein an X coordinate and a Z coordinate of the center of the virtual thin disk are obtained with respect to an angle β and an arbitrary turning angle θ of the C axis. program. The virtual thin disk is defined by a tool coordinate system consisting of a number of points around its surface,
When it is assumed that the virtual thin disk is swung by the angle β in order to orient the perpendicular thin disk in a direction perpendicular to the surface of the three-dimensional shape model, at least one of a plurality of points defined in the tool coordinate system is used. If the point is inside the three-dimensional shape model, it is determined that the virtual thin disk has interfered with the three-dimensional shape model,
The tool according to claim 19, wherein the direction of the virtual thin disk is swung by an angle β-90 °, and the tip of the virtual thin disk is positioned so as to contact the machining point of the three-dimensional shape model. Route generator. The tool path generation program according to any one of claims 17 to 20,
A band saw blade that runs parallel to the direction perpendicular to the C axis, the band saw blade is movable in the Z axis direction parallel to the Z axis and the F direction perpendicular to the Z axis as a whole, and the band saw blade Add a third tool path generation program necessary for three-dimensional machining using a band saw that can be turned so as to incline in the direction of the Z-axis,
In the third tool path generation program, a virtual band saw tool having the same shape as the band saw blade of the band saw machine is parallel to the Z axis with respect to the three-dimensional shape model in which the turning angle θ of the C axis is zero degrees. When slicing in the Z-axis direction, assuming that the Z-axis direction and the F-direction perpendicular to the Z-axis move,
A large number of virtual slice sections parallel to the XY plane are formed at appropriate intervals in the Z-axis direction with respect to the three-dimensional shape model, and a maximum point Fmax and a minimum point Fmin in the + F direction are calculated in each virtual slice section. The maximum contour line connecting Fmax and the minimum contour line connecting each Fmin are calculated, and the maximum offset line for the maximum contour line and the minimum offset line for the minimum contour line are calculated. A tool path generation program that uses at least one of the maximum part offset line and the minimum part offset line as a tool path of the virtual band saw tool. In the tool path generation program according to any one of claims 17 to 21,
The polishing belt includes a polishing belt that runs parallel to a direction orthogonal to the C-axis, the polishing belt is movable in the Z-axis direction parallel to the Z-axis and the F-direction orthogonal to the Z-axis as a whole, and the polishing belt A fourth tool path generation program necessary for three-dimensional machining using a belt sander that can be turned so as to be inclined with respect to the Z-axis direction,
As the fourth tool path generation program, when a virtual polishing tool having the same shape as the polishing belt of the belt sander is polished with respect to the three-dimensional shape model in which the turning angle θ of the C axis is zero degrees, On the premise of moving in the Z-axis direction and the F-direction orthogonal to the Z-axis,
A large number of virtual slice sections parallel to the XY plane are formed at appropriate intervals in the Z-axis direction with respect to the three-dimensional shape model, and a maximum point Fmax and a minimum point Fmin in the + F direction are calculated in each virtual slice section. The maximum contour line connecting Fmax and the minimum contour line connecting each Fmin are calculated, and at least one of the maximum contour line and the minimum contour line is used as a tool of the virtual polishing tool. A tool path generation program for generating a path. A recording medium in which the tool path generation program according to any one of claims 17 to 22 is recorded.

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