JP5872869B2 - Numerical control device that performs machining by cutting point command on the back of the tool - Google Patents

Description

  The present invention controls a machine tool that processes at least three linear axes with respect to a workpiece (workpiece) mounted on a table, and also includes a command cutting point position commanded by a machining program, a command cutting surface vertical direction, a tool The present invention relates to a numerical control apparatus having a cutting point command control unit for obtaining a control point position of each axis for each interpolation period from a diameter correction amount, a tool length correction amount, and a tool thickness correction amount. Further, the machine tool is a multi-axis machine tool that performs machining with two rotary axes in addition to the three linear axes, or the cutting point command control unit further includes a tool taper angle and a tool back corner commanded by a machining program. The present invention relates to a numerical controller that is a cutting point command control unit that also takes into account the R correction amount or the tool tip surface corner R correction amount.

In a multi-axis machine tool that performs machining with at least three linear axes and two rotary axes, the command cutting point position (tool cutting edge position for cutting the workpiece), command cutting surface vertical direction, command tool direction, and tool radius correction are processed according to the machining program. Command and the amount of tool length compensation, and the interpolation cutting point position, interpolation cutting surface vertical direction vector, interpolation tool direction vector, interpolation tool radius compensation vector, and interpolation tool length compensation vector are obtained for each interpolation cycle, and these interpolation cutting points are obtained. 2. Description of the Related Art A numerical control device is known that is driven by obtaining control point positions of three linear axes and two rotary axes from a position, an interpolation tool radius correction vector, and an interpolation tool length correction vector. As described above, the command cutting point position, the command cutting surface vertical direction, the command tool direction, the tool radius correction amount, and the tool length correction amount are commanded by the machining program, and the actual cutting point position on the workpiece becomes the interpolation cutting point position. Thus, the command method and the control method for obtaining and driving the control point position of each axis are called cutting point commands.
This cutting point command is used not only in a multi-axis machine tool but also in a machine tool that does not have a rotation axis and performs machining with at least three linear axes. In this case, since the interpolation tool direction vector and the interpolation tool length correction vector do not change every interpolation cycle, they become a constant tool direction vector and a tool length correction vector.

In general, the cutting point command is often used in a multi-axis machine tool that performs machining with at least three linear axes and two rotation axes. Therefore, the following description of the prior art will be described for a multi-axis machine tool.
In Patent Document 1, a multi-axis machine tool having a rotary table, that is, a mixed multi-axis machine tool (paragraph 0062, FIG. 1) in which a table is rotated by one rotary axis and a tool head is rotated by another rotary axis. In a table rotating multi-axis machine tool (paragraph 0062, FIG. 2) that rotates a table with two rotating shafts, a technique for issuing a cutting point command by “cutting points on a hemisphere at the tip of a ball end mill tool” (claim 10). (Paragraph 0023, paragraph 0064, FIG. 14, FIG. 17) and a technique (paragraph 0064, FIG. 16) for issuing a cutting point command according to “the cutting point of the tip surface of the flat end mill tool” (claim 11). .
In Patent Document 2, in a tool head rotating type multi-axis machine tool having a rotating tool head, a technique for issuing a cutting point command by a “mill tool not having a corner R portion” (the first to eighth lines in FIG. 1, FIG. 2 and FIG. 6) and a technique for performing a cutting point command using a “mill tool having a corner R portion” (first to eighth lines of FIG. 2, FIG. 7).
In these conventional techniques, when the tool is viewed from the side, the end point of the tool front end surface or the corner R portion of the extension is set as the cutting point (see FIGS. 1 and 2).

On the other hand, in recent years, the types of tools have been diversified, and tools that perform machining at the corner R portion on the back of the tool as shown in FIG. 3 have appeared. In particular, such tools are also used in grinding tools (grinders). FIG. 4 is a perspective view of the tool shown in FIG.
Further, a tool to be processed at the end point on the back surface of the tool as shown in FIG. FIG. 6 is a perspective view of the tool shown in FIG.

Japanese Patent No. 3643098 JP 2008-287471 A

For such tool cutting point commands, the cutting point command is taken into consideration the tool thickness correction amount shown in FIGS. 3 and 5 and the tool back corner R correction amount (corner R radius) at the corner R portion on the back of the tool. However, there is no technical idea in consideration of the tool thickness correction amount and the tool back corner R correction amount in the control of the cutting point command of the above-described conventional technology.
In addition, a tool having a taper angle on the tool side surface and a tool in which the tool tip surface corner R correction amount and the tool rear corner R correction amount in the corner R portion of the tool tip surface are different are assumed in the future. 7 and 8 show side views of such a tool. For convenience, the work is omitted. In the control of the cutting point command by such a tool, there has been no technical idea considering the tool thickness correction amount, the taper angle, the tool tip surface corner R correction amount, or the tool back corner R correction amount.
For this reason, when machining is performed at the corner R or end point on the back of the tool, the control point position of each axis is commanded in consideration of such machining when the machining program is created by the CAM, or the center position of the tool tip surface Had to be ordered. Therefore, it is necessary to create a machining program with CAM for each tool. That is, if the tool is changed, it is necessary to recreate a machining program by CAM in accordance with the changed tool.

  Accordingly, an object of the present invention is to provide a numerical control device that enables machining with a cutting point command by a corner R portion or an end point on the back surface of a tool in the above-described tool in consideration of a tool thickness correction amount. In addition to the tool thickness compensation amount, the cutting point at the corner R portion and the end point on the back side of the tool is similarly applied to the tool having the taper angle of the tool side surface, the tool back side corner R compensation amount, and the tool tip surface corner R compensation amount. It is to provide a numerical control device that enables processing by command. Furthermore, a numerical control device is provided that enables a cutting point command by such a tool in a machine tool having at least three linear axes and a multi-axis machine tool having at least two linear axes and two rotational axes. That is.

In the invention according to claim 1 of the present application, the tool is moved relative to the workpiece by moving at least three linear axes to the control point position with respect to the workpiece (workpiece) attached to the table. In a numerical control device for controlling a machine tool that processes the workpiece at a cutting point, a command cutting point position commanded by a machining program, a command cutting surface vertical vector, a tool radius correction amount, a tool length correction amount, and a tool tip surface A cutting point command reading unit that reads a tool thickness correction amount, which is a distance from the back of the tool, and reads cutting point command reading data, and an interpolation cutting point position and interpolation tool diameter correction for each interpolation cycle based on the cutting point command reading data. A vector is obtained and used as cutting point command interpolation data, and control of the three linear axes is performed from the cutting point command interpolation data, the tool length correction amount, and the tool thickness correction amount. It has a cutting point instruction control unit for determining the position, the at least numerical controller and drives each axis to move the three linear axes to the control point position.
According to a second aspect of the present invention, the cutting point command reading unit is configured such that the commanded cutting point position commanded by a machining program, the commanded cutting surface vertical vector, the tool radius correction amount, the tool length correction amount, and the tool thickness. The cutting point command reading unit that reads the tool back corner R correction amount in addition to the correction amount and uses the cutting point command reading data as the cutting point command reading data. The cutting point command control unit performs interpolation based on the cutting point command reading data. In addition to the interpolation cutting point position and the interpolation tool radius correction vector for each period, an interpolation corner R correction vector is also obtained as the cutting point command interpolation data, and the cutting point command interpolation data, the tool length correction amount, the tool The cutting point command control unit for obtaining a control point position of the three linear axes from a thickness correction amount and a tool back corner R correction amount. A value control unit.

  According to a third aspect of the present invention, the cutting point command reading unit is configured such that the commanded cutting point position commanded by a machining program, the commanded cutting surface vertical vector, the tool radius correction amount, the tool length correction amount, and the tool thickness. The cutting point command reading unit that reads a tool taper angle in addition to a correction amount and sets the cutting point command read data as the cutting point command read data, and the cutting point command control unit performs an interpolation cycle based on the cutting point command read data. The interpolation cutting point position and the interpolation tool radius correction vector are obtained and used as the cutting point command interpolation data. From the cutting point command interpolation data, the tool length correction amount, and the tool thickness correction amount, the control points of the three linear axes are determined. The numerical control device according to claim 1, wherein the numerical control device is a cutting point command control unit for obtaining a position.

According to a fourth aspect of the present invention, the cutting point command reading unit is configured such that the commanded cutting point position commanded by a machining program, the commanded cutting surface vertical vector, the tool radius correction amount, the tool length correction amount, and the tool thickness. The cutting point command reading unit that reads the tool back corner R correction amount, the tool tip surface corner R correction amount, and the tool taper angle in addition to the correction amount and uses the cutting point command read data as the data. Based on the cutting point command read data, an interpolation corner R correction vector is obtained in addition to the interpolation cutting point position and the interpolation tool radius correction vector for each interpolation period, and the cutting point command interpolation data is obtained. Cutting point command for obtaining the control point position of the three linear axes from the command interpolation data, the tool length correction amount, the tool thickness correction amount and the tool back corner R correction amount A numerical controller according to claim 1, characterized in that the control unit.
According to a fifth aspect of the present invention, the machine tool moves a tool to the workpiece by moving at least three linear axes and two rotation axes to a control point position with respect to a workpiece (workpiece) attached to a table. The cutting point command is a multi-axis machine tool that processes the workpiece by moving relative to the cutting point command, and the cutting point command reading unit also reads a command tool direction commanded by a machining program and uses the cutting point command reading data as the cutting point command reading data. The cutting point command control unit obtains an interpolation tool direction vector Vt and an interpolation tool length correction vector for each interpolation period based on the cutting point command read data, and uses the cutting point command interpolation data as the cutting point command interpolation data; A cutting point command control unit for obtaining control point positions of the three linear axes and the two rotating shafts from the cutting point command interpolation data, the at least linear axis Axis and the two rotation axes are numerical controller according to any one of the serial claims 1 to 4, characterized in that for driving the respective axes so as to move the control point position.

The invention according to claim 6 is the numerical control device according to claim 5, wherein the command tool direction is commanded as a command rotation axis position.
The invention according to claim 7 is the numerical controller according to claim 5, wherein the command tool direction is commanded as a command tool direction vector.
The invention according to claim 8 is the numerical control apparatus according to any one of claims 5 to 7, wherein the two rotation shafts are the two rotation shafts that rotate the tool head.
The invention according to claim 9 is the numerical control device according to any one of claims 5 to 7, wherein the two rotation shafts are the two rotation shafts that rotate the table.
The invention according to claim 10 is any one of claims 5 to 7, wherein one of the two rotary shafts is the two rotary shafts rotating the tool head and the other one rotating the table. It is a numerical control apparatus as described in.

  According to the present invention, it is possible to provide a numerical control device that enables machining in accordance with a cutting point command by a corner R portion or an end point on the back surface of a tool in the above tool in consideration of a tool thickness correction amount. In addition to the tool thickness compensation amount, the cutting point at the corner R portion and the end point on the back side of the tool is similarly applied to the tool having the taper angle of the tool side surface, the tool back side corner R compensation amount, and the tool tip surface corner R compensation amount. It is possible to provide a numerical control device that enables processing by command. Furthermore, in a machine tool having at least three linear axes and a multi-axis machine tool having at least two linear axes in addition to at least three linear axes, it is possible to provide a numerical control device that enables a cutting point command by such a tool. .

  Therefore, in the CAM, it is only necessary to create a machining program for instructing a cutting point in accordance with the machining shape regardless of the tool shape. That is, it is not necessary to create a machining program with CAM for each tool. Even if the tool is changed, there is no need to recreate a machining program with CAM. As a result, more efficient processing is possible.

It is a figure explaining that the end point of a tool front end surface is a cutting point. It is a figure explaining that the corner R part of a tool front end surface is a cutting point. It is a figure explaining the example of the tool which processes by the corner R part of a tool back surface. It is a perspective view of the tool shown in FIG. It is a figure explaining the example of the tool processed with the end point of a tool back. It is a perspective view of the tool shown in FIG. It is a figure explaining the example of the tool which has a taper angle in a tool side surface. It is a figure explaining the example of the tool from which the tool front end surface corner R correction amount and tool back surface corner R correction amount differ in the corner R part of a tool front end surface. It is a figure explaining a tool head rotation type multi-axis machine tool in which a tool head rotates on rotation axes B and C, and a tool head moves on linear axes X, Y, and Z. It is a side view of the tool attached to the tool head rotation type multi-axis machine tool shown in FIG. It is a figure which expands and draws with the one part of a workpiece | work by enlarging the upper left of the tool back surface in the tool shape of the tool shown in FIG. It is a figure explaining the example of a process program. It is a figure explaining the table rotation type multi-axis machine tool which rotates a table by two rotating shafts. It is a figure explaining the mixed type multi-axis machine tool which rotates a tool head with one rotating shaft, and rotates a table with another rotating shaft. It is a figure explaining the multi-axis machine tool in which a tool head moves with a linear axis X, Y, and Z axis. It is a figure explaining the example of the machining program performed with the multi-axis machine tool shown in FIG. It is a functional block diagram of the numerical control apparatus in the 1st Embodiment of this invention. It is a flowchart of the cutting point command control part in the 1st Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
The numerical control device according to the embodiment of the present invention described below enables processing with a command using a corner R portion or an end point on the back surface of a tool such as a grinding tool as a cutting point. The present invention controls a machine tool that processes at least three linear axes with respect to a workpiece (workpiece) mounted on a table, and also instructs a command cutting point position, a command cutting surface vertical direction, a tool diameter commanded by a machining program. It is a numerical control device having a cutting point command control unit for obtaining a control point position of each axis from a correction amount, a tool length correction amount, and a tool thickness correction amount. The machine tool is a multi-axis machine tool that performs machining with two rotation axes in addition to the three linear axes. The cutting point command control unit further determines a control point position of each axis in consideration of a tool taper angle, a tool back corner R correction amount, or a tool tip surface corner R correction amount commanded by a machining program. It is.

<Embodiment>
1) First Embodiment As described above, the present invention provides a tool thickness correction amount, a tool side taper angle, a tool back corner R correction amount, and a tool tip surface corner R correction amount. Enables machining with cutting point commands at corner R and end points. Further, a cutting point command is enabled in a machine tool having at least three linear axes and a multi-axis machine tool having two rotational axes in addition to at least three linear axes.
In the first embodiment, the most complicated embodiment among the many combinations thereof will be described. That is, in a multi-axis machine tool that performs machining with at least three straight axes and two rotation axes, an embodiment using a tool having a tool back corner R correction amount, a tool tip surface corner R correction amount, and a tool taper angle as shown in FIG. To do. By simplifying each element from the first embodiment, application to a machine tool that performs machining with at least three linear axes that do not have a rotation axis, and application to a simpler tool will be described after the second embodiment. This will be described in the embodiment.

  As shown in FIG. 9, the target multi-axis machine tool places the workpiece 1 on the table 3, the tool head rotates on the rotary axes B and C, and the tool head moves on the linear axes X, Y, and Z axes. Tool head rotating type multi-axis machine tool. In the figure, the tool (grinder) is drawn larger. Here, the rotation axes are the B axis and the C axis, but there are other multi-axis machine tools in which the A axis and the B axis are combined or the A axis and the C axis are combined. Although the tool head is supposed to move along the linear axes X, Y, and Z, there are other multi-axis machine tools that move the table along the X, Y, and Z axes. There are also multi-axis machine tools to which other linear axes for operating a tool magazine or a pallet on which workpieces are not shown are added. The present invention can be similarly applied to such other multi-axis machine tools. The cutting point position on the workpiece is commanded by the X, Y and Z axis positions of the program coordinate system. The tool shape is shown in its side view (see FIG. 10). Work 1 is omitted. The control point position is the rotation center intersection of the B and C axes. FIG. 11 is an enlarged view of the upper left side of the tool back in the tool shape. FIG. 11 also shows a work.

A machining program example is instructed as shown in FIG. Here, G43.8 is a G code for starting a cutting point command. H_ is a tool length correction amount number, D_ is a tool diameter correction amount number, T_ is a tool thickness correction amount number, L_ is a taper angle number, R_ is a tool back corner R correction amount number, and Q_ is a tool tip surface corner R correction amount number. This is a command.
Tool length correction amount corresponding to each tool length correction amount number, tool diameter correction amount corresponding to each tool diameter correction amount number, tool thickness correction amount corresponding to each tool thickness correction amount number, and each taper angle number Taper angle corresponding to each tool, tool back tool tip surface corner R correction amount corresponding to each tool back tool tip surface corner R correction amount number, and tool tip surface corner corresponding to each tool tip surface corner R correction amount number The R correction amount is set in advance, the tool length correction amount Th by the H_ command, the tool radius correction amount Tr by the D_ command, the tool thickness correction amount Tt by the T_ command, and the taper angles θ, R_ by the L_ command. The tool tip corner R correction amount Cf is commanded by the command of the tool back surface corner R correction amount Cb and Q_. Of course, these data corresponding to each tool number may be set as one group, and these data may be instructed collectively by instructing one tool number.

  G49 is a G code for canceling the cutting point command, and X_, Y_, and Z_ of each block in the meantime are commands for commanding the commanded cutting point position on the workpiece in the program coordinate system. B_ and C_ are commands for instructing a command tool direction as a command rotation axis position. The command tool direction can also be commanded as a command tool direction vector using vectors such as U_, V_, and W_ instead of B_ and C_. I_, J_, and K_ are commands of a command cutting surface vertical vector that commands a vector in a direction perpendicular to the cutting surface at the commanded cutting point position. Assume that U_, V_, W_ or I_, J_, K_ are commanded with unit vectors. F_ is a command for commanding the machining speed between the commanded cutting point positions.

  The present invention is applied to a cutting point command, that is, a machining program from G43.8 to G49 command. These command data, D_, H_, T_, L_, R_, Q_, X_, Y_, Z_, B_, commanded by the machining program in the cutting point command reading unit (see the cutting point command reading unit 12 in FIG. 17). , C_ (or U, V, W), I_, J_, K_, tool radius compensation amount Tr, tool length compensation amount Th, tool thickness compensation amount Tt, taper angle θ, tool back corner radius compensation amount Cb, Tool tip surface corner R correction amount Cf, command cutting point position (X_, Y_, Z_), command cutting surface vertical vector (I_, J_, K_), command tool direction (B_, C_ or U_, V_, W_), The cutting point command read data is used.

  In the above, the command of B_ and C_ can be used as the command of the command tool direction vector by the calculation of Formula 1. In the following description, it is assumed that the command tool direction vector is commanded by U_, V_, and W_.

In response to the commands (X, Y, Z), (I, J, K), (U, V, W), interpolation is performed between the blocks at each interpolation cycle. This is a prior art and will not be described in detail. The position interpolated for (X, Y, Z) is the interpolation cutting point position Pc (Xc, Yc, Zc) ^T , and the direction interpolated for (I, J, K) is the interpolated cutting surface vertical vector Vp (Vpx, Vpy, Vpz). ) The direction interpolated with respect to ^T and (U, V, W) is set as an interpolation tool direction vector Vt (Vtx, Vty, Vtz) ^T. The interpolation cutting surface vertical vector Vp and the interpolation tool direction vector Vt are unit vectors. Here, “ ^T ” represents transposition. The vector notation “ ^T ” in the drawings such as FIG.
From these, the interpolation corner R correction vector Vc (Vcx, Vcy, Vcz) is obtained as shown in Equation 2. An interpolation tool length correction vector Vh (Vhx, Vhy, Vhz) is obtained as shown in Equation 3.

The interpolation tool radius correction vector Vr (Vrx, Vry, Vrz) is obtained as follows.
Vv (Vvx, Vvy, Vvz) is a unit vector perpendicular to Vp and Vt, that is, a vector perpendicular to the paper surface of FIG. 11 (facing to the front of the paper surface). Vv (Vvx, Vvy, Vvz) is expressed by Equation 4. β is an angle formed by Vp and Vr, α is an angle formed by Vp and Vt, and there is a relationship of Formula 5 (see FIG. 11). The matrix Mr is a matrix that is rotated by β with Vv as the rotation center axis (see Equation 6). Lr is the length of Vr (see Equation 7 and FIGS. 10 and 11). A vector obtained by multiplying Vp by Mr and setting the length to Lr is Vr (see Equation 8). The symbol “×” indicates an outer product, the symbol “·” indicates an inner product, and “*” indicates multiplication.

These interpolation cutting point position Pc, interpolation tool radius correction vector Vr, interpolation corner R correction vector Vc, interpolation tool direction vector Vt, and interpolation tool length correction vector Vh are cutting point command interpolation data.
From the cutting point command interpolation data, the control point position Pm (Xm, Ym, Zm) of the three linear axes as shown in Equation 9 and the control point position (Bm, Cm) of the two rotary shafts as shown in Equation 10 are obtained. Each axis is driven so as to move to the control point position. The cutting point command control unit performs these calculations. As a result, machining with a cutting point command by the corner R portion on the back surface of the tool can be performed.

  Here, the tool head rotating type multi-axis machine tool has been described. However, in addition to the multi-axis machine tool, a table in which the tool 2 is attached to a tool head moving in the Z-axis direction and the table 5 is rotated around the two rotation axes. A rotary multi-axis machine tool (see FIG. 13), or a mixed multi-axis machine tool (FIG. 14) that rotates a tool head to which the tool 2 is attached with one rotary shaft and rotates the table 7 with another rotary shaft. See also). The present invention is equally applicable to those multi-axis machine tools.

  Furthermore, although it was set as the example of the 5-axis machine tool which has at least 3 linear axes and 2 rotating axes here, the rotating shaft becomes unnecessary by making the position of 1 axis out of 2 rotating axes into a fixed position, The present invention can also be applied to a four-axis machine tool having at least three linear axes and one rotation axis.

2) Second Embodiment In the first embodiment, the tool R has a corner R portion and a tool having a taper angle. However, the tool R has no corner R portion and a taper angle based on the first embodiment. The case of a tool will be described.
In the case of a tool that does not have a corner R portion on the back side of the tool as shown in FIG. 7, there is no command R_ for the tool back corner R correction amount number in the first embodiment. The command Q_ for the tool tip surface corner R correction amount number is also unnecessary. Therefore, in the cutting point command reading unit (see FIG. 17), the tool radius correction amount Tr, tool length correction amount Th, tool thickness correction amount Tt, taper angle θ, command cutting point position (X_, Y_, Z_), command cutting The surface vertical vector (I_, J_, K_) and the command tool direction (B_, C_ or U_, V_, W_) are used as cutting point command read data. In the equations (2) to (10), Cb = Cf = 0 may be set. The interpolation cutting point position Pc, the interpolation tool radius correction vector Vr, the interpolation tool direction vector Vt, and the interpolation tool length correction vector Vh are the cutting point command interpolation data. From these cutting point command interpolation data, three linear axes and two rotary axes 2 are obtained. The axis control point position is obtained, and each axis is driven to move to the control point position.

  In the case of a tool having no taper angle as shown in FIGS. 3 and 4, there is no command L_ for the taper angle number in the first embodiment. The command Q_ for the tool tip surface corner R correction amount number is also unnecessary. Therefore, at the cutting point command reading unit, the tool radius correction amount Tr, the tool length correction amount Th, the tool thickness correction amount Tt, the tool back corner R correction amount Cb, the command cutting point position (X_, Y_, Z_), the command cutting surface The vertical vector (I_, J_, K_) and the command tool direction (B_, C_ or U_, V_, W_) are used as cutting point command read data. In the equations (2) to (10), θ = 0 may be set. At this time, Expression 7 becomes Lr = Tr−Cb and Cf does not appear. The interpolation cutting point position Pc, the interpolation tool radius correction vector Vr, the interpolation corner R correction vector Vc, the interpolation tool direction vector Vt, and the interpolation tool length correction vector Vh are the cutting point command interpolation data, and straight lines are derived from these cutting point command interpolation data. The control point positions of the three axes and the two rotation axes are obtained, and each axis is driven to move to the control point position.

  In the case of a tool that does not have the corner R portion on the tool back surface and the taper angle as shown in FIGS. 5 and 6, the command R_ of the tool back surface corner R correction amount number and the tool tip surface corner R correction amount number in the first embodiment are used. There is no command Q_ and taper angle number command L_. Therefore, in the cutting point command reading unit, the tool radius correction amount Tr, the tool length correction amount Th, the tool thickness correction amount Tt, the command cutting point position (X_, Y_, Z_), the command cutting surface vertical vector (I_, J_, K_). ), The command tool direction (B_, C_ or U_, V_, W_) is used as cutting point command read data. In Equations 2 to 10, Cb = Cf = 0 and θ = 0. The interpolation cutting point position Pc, the interpolation tool radius correction vector Vr, the interpolation tool direction vector Vt, and the interpolation tool length correction vector Vh are the cutting point command interpolation data. From these cutting point command interpolation data, three linear axes and two rotary axes 2 are obtained. The axis control point position is obtained, and each axis is driven to move to the control point position.

3) Third Embodiment In the first embodiment, a multi-axis machine tool that performs machining by at least three linear axes and two rotation axes has been described. However, a machine tool that does not have a rotation axis based on the first embodiment. The case will be described.
In the target machine tool, the tool head moves along the linear axes X, Y, and Z as shown in FIG. There are other machine tools that move the table along the X, Y, and Z axes. In addition, as described in the first embodiment, there is a machine tool to which another linear axis for operating a tool magazine (not shown) or a pallet on which a workpiece is placed is added.
In the case of a machine tool that performs machining with at least three linear axes, there is no command tool direction command in the first embodiment. That is, there is no B_, C_ command in the machining program shown in FIG. There are no U_, V_, and W_ commands instead (see FIG. 16). Therefore, these command data, D_, H_, T_, L_, R_, Q_, X_, Y_, Z_, I_, J_, K_, which are commanded by the machining program, are read by the cutting point command reading unit (see FIG. 17). , Tool diameter correction amount Tr, tool length correction amount Th, tool thickness correction amount Tt, taper angle θ, tool back corner R correction amount Cb, tool tip surface corner R correction amount Cf, command cutting point position (X_, Y_, Z_ ), The command cutting surface vertical vector (I_, J_, K_) is used as the cutting point command read data.

  The tool direction is set as a separate parameter. In the machine tool of FIG. 15, the tool direction is the Z-axis direction. The interpolation tool direction vector Vt in the first embodiment is a tool direction vector Vt (0, 0, 1) in this embodiment. In the first embodiment, the direction interpolated for each interpolation cycle with respect to the (U, V, W) command of each block is set as the interpolation tool direction vector Vt, and the interpolation tool length correction vector Vh is expressed by the equation 3 as the interpolation cycle. However, since the tool direction vector is constant in this embodiment, there is no need to obtain it every interpolation cycle. As a calculation corresponding to Equation 3, when the tool length correction amount Th, the tool thickness correction amount Tt, or the tool back corner R correction amount Cb is commanded, these amounts and the set tool direction Vt = (0, 0). , 1), the tool length correction vector Vh is calculated as shown in Equation 11. The tool length correction vector Vh and the tool direction vector Vt obtained here are used in Equation 4, Equation 5, Equation 8, Equation 9 and the like, similar to the interpolation tool length correction vector Vh and the interpolation tool direction vector Vt. To do. Therefore, they are the same symbols as the interpolation tool length correction vector Vh and the interpolation tool direction vector Vt. However, as described above, the tool length correction vector Vh is not a vector obtained for each interpolation period, but the tool length correction amount Th, the tool When the thickness correction amount Tt or the tool back corner R correction amount Cb is commanded, this is a vector obtained from these amounts and the tool direction vector Vt, and the tool direction vector Vt is a set vector.

  Calculations of Formula 2 and Formula 4 to Formula 9 other than Formula 11 are the same as those in the first embodiment. Therefore, the interpolation cutting point position Pc, the interpolation tool radius correction vector Vr, and the interpolation corner R correction vector Vc are the cutting point command interpolation data, and the cutting point command interpolation data, the tool length correction amount Th, and the tool rear corner R correction amount. The control point positions of the three linear axes are obtained from Cb and the tool thickness correction amount Tt, and each axis is driven to move to the control point position.

4) Fourth Embodiment In the third embodiment, the tool has a corner R portion on the back of the tool and a tool having a taper angle in a machine tool that performs machining with at least three linear axes. The case of a tool having no corner R portion or taper angle on the back of the tool will be described.

  In the case of a tool that does not have a corner R portion on the back side of the tool as shown in FIG. 7, there is no command R_ for the back side corner R correction amount number in the third embodiment. The command Q_ for the tool tip surface corner R correction amount number is also unnecessary. Therefore, in the cutting point command reading unit, the tool radius correction amount Tr, the tool length correction amount Th, the tool thickness correction amount Tt, the taper angle θ, the command cutting point position (X_, Y_, Z_), the command cutting surface vertical vector (I_ , J_, K_) are cutting point command read data. In Formula 2, Formula 11, Formula 4 to Formula 9, Cb = Cf = 0 may be set. The interpolation cutting point position Pc and the interpolation tool radius correction vector Vr are cutting point command interpolation data, and the control point position of the three linear axes is determined from the cutting point command interpolation data, the tool length correction amount Th, and the tool thickness correction amount Tt. Find and drive each axis to move to the control point position.

  In the case of a tool having no taper angle as shown in FIGS. 3 and 4, there is no command L_ for the taper angle number in the third embodiment. The command Q_ for the tool tip surface corner R correction amount number is also unnecessary. Therefore, at the cutting point command reading unit, the tool radius correction amount Tr, the tool length correction amount Th, the tool thickness correction amount Tt, the tool back corner R correction amount Cb, the command cutting point position (X_, Y_, Z_), the command cutting surface Vertical vectors (I_, J_, K_) are used as cutting point command read data. In Equation 2, Equation 11, Equation 4 to Equation 9, θ = 0 may be set. At this time, Expression 7 becomes Lr = Tr−Cb and Cf does not appear. The interpolation cutting point position Pc, the interpolation tool radius correction vector Vr, and the interpolation corner R correction vector Vc are the cutting point command interpolation data, the cutting point command interpolation data, the tool length correction amount Th, the tool thickness correction amount Tt, and the tool back surface. The control point positions of the three linear axes are obtained from the corner R correction amount Cb, and each axis is driven to move to the control point position.

  In the case of a tool having neither the corner R portion on the tool rear surface nor the taper angle as shown in FIGS. 5 and 6, the tool rear corner R correction amount command R_ in the third embodiment, the tool tip surface corner R correction amount number There is no command Q_ and taper angle number command L_. Therefore, in the cutting point command reading unit, the tool radius correction amount Tr, the tool length correction amount Th, the tool thickness correction amount Tt, the command cutting point position (X_, Y_, Z_), the command cutting surface vertical vector (I_, J_, K_). ) Is the cutting point command read data. In Equation 2, Equation 11, Equation 4 to Equation 9, Cb = Cf = 0 and θ = 0. The interpolation cutting point position Pc and the interpolation tool radius correction vector Vr are cutting point command interpolation data, and the control point position of the three linear axes is determined from the cutting point command interpolation data, the tool length correction amount Th, and the tool thickness correction amount Tt. Find and drive each axis to move to the control point position.

  Next, the numerical controller according to the first embodiment of the present invention will be described with reference to FIG. In general, a numerical control apparatus reads and analyzes a machining program command by a command reading analysis unit 10 to generate interpolation data, and an interpolation unit 16 performs interpolation based on the interpolation data to move each axis to a position to be moved. And the servos 22X, 22Y, 22Z, 22B (A), 22C of each axis are driven according to the position.

  In the present invention, the cutting point command reading unit 12 belonging to the command reading analysis unit 10 reads the machining program and creates cutting point command read data 14. Further, the cutting point command control unit 18 belonging to the interpolation unit 16 creates cutting point command interpolation data 20 and obtains the control point position of each axis. The servos 22X, 22Y, 22Z, 22B (A), 22C of each axis are driven so as to move to the determined control point position of each axis.

FIG. 18 shows a flowchart of the cutting point command control unit in the first embodiment. Hereinafter, it demonstrates according to each step.
[Step SA01] The cutting point command read data (Tr, Th, Tt, θ, Cb, Cf) read by the cutting point command reading unit is obtained.
[Step SA02] The position interpolated for the (X, Y, Z) command of each block is set as the interpolation cutting point position Pc (Xc, Yc, Zc), and the direction interpolated for the (I, J, K) command is interpolated. A surface vertical vector Vp (Vpx, Vpy, Vpz) is set, and a direction interpolated with respect to the (U, V, W) command is set as an interpolation tool direction vector Vt (Vtx, Vty, Vtz).
[Step SA03] Formulas 2 to 8 are calculated to obtain cutting point command interpolation data (Pc, Vc, Vr, Vh, Vt).
[Step SA04] Pm (Xm, Ym, Zm), Bm, and Cm are obtained by calculation of Equation 9 and Equation 10.

1 Work 2 Tool 3 Table

5 tables

7 tables

10 Command Reading Analysis Unit 12 Cutting Point Command Reading Unit 14 Cutting Point Command Reading Data 16 Interpolation Unit 18 Cutting Point Command Control Unit 20 Cutting Point Command Interpolation Data 22X X-axis Servo 22Y Y-axis Servo 22Z Z-axis Servo 22B (A) B ( A) Axis servo 22C C axis servo

Claims (10)

A machine for machining the workpiece at the cutting point of the tool by moving the tool relative to the workpiece by moving at least three linear axes to the control point position with respect to the workpiece (workpiece) attached to the table. In the numerical control device that controls the machine,
The cutting point command read data is read by reading the command cutting point position commanded by the machining program, the command cut surface vertical vector, the tool radius correction amount, the tool length correction amount, and the tool thickness correction amount which is the distance between the tool tip surface and the tool back surface. Cutting point command reading unit to perform,
Based on the cutting point command read data, an interpolation cutting point position and an interpolation tool radius correction vector are obtained for each interpolation period to obtain cutting point command interpolation data. The cutting point command interpolation data, the tool length correction amount, and the tool thickness A cutting point command control unit for obtaining a control point position of the three linear axes from a correction amount;
A numerical controller that drives each axis so as to move the at least three linear axes to the control point position. The cutting point command reading unit includes a tool back corner in addition to the command cutting point position commanded by a machining program, the command cutting surface vertical vector, the tool radius correction amount, the tool length correction amount, and the tool thickness correction amount. The cutting point command reading unit that also reads the R correction amount and sets the cutting point command read data;
The cutting point command control unit obtains an interpolation corner R correction vector in addition to the interpolation cutting point position and the interpolation tool radius correction vector for each interpolation period based on the cutting point command read data, and calculates the cutting point command. A cutting point command control unit that obtains control point positions of the three linear axes from the cutting point command interpolation data, the tool length correction amount, the tool thickness correction amount, and the tool back corner R correction amount as interpolation data. The numerical control apparatus according to claim 1. The cutting point command reading unit includes a tool taper angle in addition to the command cutting point position commanded by a machining program, the command cutting surface vertical vector, the tool radius correction amount, the tool length correction amount, and the tool thickness correction amount. Is also the cutting point command reading unit that reads the cutting point command read data,
The cutting point command control unit obtains the interpolation cutting point position and the interpolation tool radius correction vector for each interpolation period based on the cutting point command read data, and sets the cutting point command interpolation data as the cutting point command interpolation data. The numerical control device according to claim 1, wherein the numerical control device is a cutting point command control unit that obtains control point positions of the three linear axes from data, the tool length correction amount, and the tool thickness correction amount. The cutting point command reading unit includes a tool back corner in addition to the command cutting point position commanded by a machining program, the command cutting surface vertical vector, the tool radius correction amount, the tool length correction amount, and the tool thickness correction amount. The cutting point command reading unit that also reads the R correction amount, the tool tip surface corner R correction amount, and the tool taper angle and sets the cutting point command read data;
The cutting point command control unit obtains an interpolation corner R correction vector in addition to the interpolation cutting point position and the interpolation tool radius correction vector for each interpolation period based on the cutting point command read data, and calculates the cutting point command. A cutting point command control unit that obtains control point positions of the three linear axes from the cutting point command interpolation data, the tool length correction amount, the tool thickness correction amount, and the tool back corner R correction amount as interpolation data. The numerical control apparatus according to claim 1. The machine tool moves the tool relative to the workpiece by moving at least three linear axes and two rotation axes to the control point position with respect to the workpiece (workpiece) attached to the table. Is a multi-axis machine tool
The cutting point command reading unit is the cutting point command reading unit that reads the command tool direction commanded by a machining program and sets the cutting point command read data,
The cutting point command control unit obtains an interpolation tool direction vector Vt and an interpolation tool length correction vector for each interpolation period based on the cutting point command read data, and uses the cutting point command interpolation data as the cutting point command interpolation data. A cutting point command control unit for obtaining control point positions of the three linear axes and the two rotary axes from data;
5. The numerical control device according to claim 1, wherein each of the axes is driven so as to move the at least three linear axes and the two rotation axes to the control point position. 6. .   The numerical control device according to claim 5, wherein the command tool direction is commanded as a command rotation axis position.   The numerical controller according to claim 5, wherein the command tool direction is commanded as a command tool direction vector.   The numerical control device according to claim 5, wherein the two rotation shafts are the two rotation shafts that rotate the tool head.   The numerical control apparatus according to claim 5, wherein the two rotation shafts are the two rotation shafts that rotate the table.   8. The numerical controller according to claim 5, wherein one of the two rotation shafts is the two rotation shafts that rotate the tool head and the other one rotates the table. 9.

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