US 7,283,889 B2Granted

Numerical control device, and numerical control method

AssigneeFanuc Corporation

InventorsToshiaki Otsuki, Hideo Ogino, Takafumi Sasaki

Life of this patent

Estimating the term…

Loading patent…

Abstract

A machine has a tool head which rotates on a C-axis (about the Z-axis) and an A-axis (about the X-axis). A tool length vector is multiplied by a matrix whereby a misalignment component δs-H and the incline error (αs-H, βs-H, γs-H) of a spindle are corrected so that the tool length vector due to the misalignment of the spindle is obtained. The vector thus obtained is further multiplied by a transformation matrix that includes a rotation instruction α for the A-axis and misalignments of the A-axis δa-H (αa-H, βa-H, γa-H) to correct the misalignment of the A-axis so that the tool length vector as found when the A-axis has rotated by an equivalent of instruction α is determined. The vector thus determined is further multiplied by a transformation matrix that includes a rotation instruction c for the C-axis and misalignments of the C-axis δac-H (αc-H, βc-H, γc-H) to correct the misalignment of the C-axis, so that a tool length vector as found when the C-axis has rotated by an equivalent of instruction c is determined. The tool length vector thus determined is added to the vector of positional instruction values (x, y, z) and a workpiece origin offset vector Mwo-H, so that the machine position Vm-H′ is obtained.

Claims3

Dependent claims

A numerical control method that uses a numerical control device for a machine, the machine having at least three axes of linear motion, a first axis of rotation for rotating a tool head, and a second axis of rotation for rotating the tool head, the second axis of rotation being arranged above the first axis of rotation, said method comprising:

obtaining a first actual tool length vector for which a tool length vector has been corrected, using a transformation matrix that is made from a reference position at which there is no mechanical error in the turning center of a spindle and an amount of misalignment of an actual turning center of the spindle from the reference position of the turning center of the spindle;
rotating said first actual tool length vector by an amount in correspondence with an instruction for the second axis of rotation, by multiplying the first actual tool length vector by a transformation matrix that is made from a reference position at which there is no mechanical error in the second axis of rotation, an amount of misalignment of an actual second axis of rotation from the reference position, and an instruction position for the second axis of rotation, thereby obtaining a second actual tool length vector for which the misalignment of the second axis of rotation has been corrected;
rotating said second actual tool length vector by an amount in correspondence with an instruction for the first axis of rotation, by multiplying the second actual tool length vector by a transformation matrix that is made from a reference position at which there is no mechanical error in the first axis of rotation, an amount of misalignment of the actual second axis of rotation and an actual first axis of rotation, an amount of misalignment of the actual first axis of rotation from the reference position of the first axis of rotations, and an instruction position for the first axis of rotation, thereby obtaining a third actual tool length vector for which the misalignment of the first axis of rotation has been corrected;
adding an instruction position vector and workpiece origin offset vector to the third actual tool length vector to obtain a machine position;
and
driving the axes of linear motion and the first axis of rotation and the second axis of rotation to the machine position thus obtained.

3 more elements

A numerical control method that uses a numerical control device for a machine, the machine having at least three axes of linear motion, a first axis of rotation for rotating a table, and a second axis of rotation for rotating the table, the second axis of rotation being arranged above the first axis of rotation, said method comprising:

adding, to an instruction position in a table coordinate system, an offset of an origin of the table coordinate system to obtain an instruction position in a machine coordinate system;
rotating the instruction position in the machine coordinate system by an amount in correspondence with an instruction for the second axis of rotation, by multiplying a vector of the instruction position in the machine coordinate system by a transformation matrix that is made from a reference position at which there is no mechanical error in the second axis of rotation, an amount of misalignment of an actual second axis of rotation from the reference position, and an instruction position for the second axis of rotation, thereby obtaining a rotational position of the second axis of rotation for which the misalignment of the second axis of rotation has been corrected;
rotating the rotational position of the second axis of rotation by an amount in correspondence with an instruction for the first axis of rotation, by multiplying a vector of the rotational position of the second axis of rotation by a transformation matrix that is made from a reference position at which there is no mechanical error in the first axis of rotation, an amount of misalignment of an actual first axis of rotation from the reference position, and an instruction position for the first axis of rotation, thereby obtaining a rotational position of the first axis of rotation for which the misalignment of the first axis of rotation has been corrected;
adding a tool length vector to the rotational position of the first axis of rotation to obtain a machine position;
and
driving the axes of linear motion and the first axis of rotation and the second axis of rotation to the machine position thus obtained.

3 more elements

A numerical control method that uses a numerical control device for a machine, the machine having at least three axes of linear motion, at least one axis of rotation for a tool head, and at least one axis of rotation for a table, said method comprising:

adding, to an instruction position in a table coordinate system, an offset of an origin of the table coordinate system to obtain an instruction position in a machine coordinate system;
rotating the instruction position in the machine coordinate system by an amount in correspondence with an instruction for the axis of rotation for the table, by multiplying a vector of the instruction position in the machine coordinate system by a transformation matrix that is made from a reference position at which there is no mechanical error in the axis of rotation for the table, an amount of misalignment of an actual axis of rotation for the table from the reference position, and an instruction position for the axis of rotation for the table, thereby obtaining a rotational position of the axis of rotation for the table for which the misalignment of the axis of rotation for the table has been corrected;
rotating a tool length vector of the tool by an amount head in correspondence with an instruction for the axis of rotation for the tool head, by multiplying the tool length vector by a transformation matrix that is made from a reference position at which there is no mechanical error in the axis of rotation for the tool head, an amount of misalignment of an actual axis of rotation for the tool head from the reference position, and an instruction position for the axis of rotation for the tool head, thereby obtaining a rotational position of the axis of rotation for the tool head for which the misalignment of the axis of rotation for the tool head has been corrected;
obtaining a machine position in accordance with the rotational position of the axis of rotation for the table and the rotational position of the axis of rotation for the tool head;
and
driving the axes of linear motion and the at least one axis of rotation for the tool head and the at least one axis of rotation for the table to the machine position thus obtained.

3 more elements

Dependencies are inferred from the claim text.

Facts

Application: 10/776,248Filed 12 Feb 2004
Priority: JP 2003-04124919 Feb 2003
Published: US 2005/0107000 A119 May 2005
Granted: 16 Oct 2007
Term ends: Not estimatedThe source records don’t support an estimate.

Classification3 codes

G05B 19/404
Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to…
G05B 2219/50297
Machine tool, machine tool null till machine tool work handling: compensation of positioning error due to a-axis, b-axis tool rotation
G05B
Control or regulating systems in general