CN109656195B - Comprehensive error calibration device and method for in-situ detection system of machine tool - Google Patents

Comprehensive error calibration device and method for in-situ detection system of machine tool Download PDF

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CN109656195B
CN109656195B CN201811548003.3A CN201811548003A CN109656195B CN 109656195 B CN109656195 B CN 109656195B CN 201811548003 A CN201811548003 A CN 201811548003A CN 109656195 B CN109656195 B CN 109656195B
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measuring
plate
measurement
cylinder
sample set
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CN109656195A (en
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张建富
冯平法
李思觅
郁鼎文
吴志军
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Tsinghua University
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    • GPHYSICS
    • G05CONTROLLING; REGULATING
    • G05BCONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
    • G05B19/00Programme-control systems
    • G05B19/02Programme-control systems electric
    • G05B19/18Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of programme data in numerical form
    • G05B19/401Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of programme data in numerical form characterised by control arrangements for measuring, e.g. calibration and initialisation, measuring workpiece for machining purposes
    • GPHYSICS
    • G05CONTROLLING; REGULATING
    • G05BCONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
    • G05B19/00Programme-control systems
    • G05B19/02Programme-control systems electric
    • G05B19/18Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of programme data in numerical form
    • G05B19/404Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of programme data in numerical form characterised by control arrangements for compensation, e.g. for backlash, overshoot, tool offset, tool wear, temperature, machine construction errors, load, inertia
    • GPHYSICS
    • G05CONTROLLING; REGULATING
    • G05BCONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
    • G05B2219/00Program-control systems
    • G05B2219/30Nc systems
    • G05B2219/37Measurements
    • G05B2219/37345Dimension of workpiece, diameter
    • GPHYSICS
    • G05CONTROLLING; REGULATING
    • G05BCONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
    • G05B2219/00Program-control systems
    • G05B2219/30Nc systems
    • G05B2219/37Measurements
    • G05B2219/37398Thickness
    • GPHYSICS
    • G05CONTROLLING; REGULATING
    • G05BCONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
    • G05B2219/00Program-control systems
    • G05B2219/30Nc systems
    • G05B2219/37Measurements
    • G05B2219/37443Program cmm, coordinate measuring machine, use cad data

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Abstract

The invention provides an error calibration device and method of a machine tool in-situ detection system. The device includes: a base plate; a measurement plate sample set mounted to the base plate; a measurement cylinder sample set mounted to the base plate; the plurality of measuring plates in the measuring plate sample set are different in inclination angle, and the axis inclination angles of the plurality of measuring cylinders in the measuring cylinder sample set are different from each other. The error calibration device of the machine tool in-situ detection system is provided with a plurality of preset inclination measurement surfaces and inclination measurement inner holes, provides reference surfaces with different inclination angles for calibration of the in-situ detection system, and is compact in structure and small in occupied volume.

Description

Comprehensive error calibration device and method for in-situ detection system of machine tool
Technical Field
The invention relates to the field of numerical control machining of machine tools, in particular to a comprehensive error calibration device and method of a machine tool in-situ detection system.
Background
The in-situ detection system of the machine tool is characterized in that a measuring head is additionally arranged on a five-axis machining center, and the machining precision of a workpiece is measured on the premise of not moving the workpiece. The measuring method can eliminate secondary clamping errors, and can reduce the deformation of the workpiece after being disassembled for large workpieces which are difficult to move or structural members with poor rigidity.
The main sources of errors of the in-situ detection system of the machine tool are measuring head errors, positioning errors of a linear shaft of the machine tool, positioning errors of a rotating shaft of the machine tool, movement errors of the machine tool, thermal errors and the like. In order to ensure the accuracy of the in-situ detection system, the in-situ detection system must be calibrated and compensated before the in-situ detection system is applied to measure the workpiece, and the accuracy of the in-situ detection system after calibration still needs to be evaluated.
Disclosure of Invention
In order to solve the above technical problems, the present invention provides a comprehensive error calibration device for a machine tool in-situ detection system, the device comprising:
a base plate;
a measurement plate sample set mounted to the base plate;
a measurement cylinder sample set mounted to the base plate;
the plurality of measuring plates in the measuring plate sample set are different in inclination angle, and the axis inclination angles of the plurality of measuring cylinders in the measuring cylinder sample set are different from each other.
Optionally, the set of measurement plate samples comprises a first subset of samples for defining a three-dimensional coordinate system together with the base plate, and a second subset of samples for providing a plurality of measurement planes in the three-dimensional coordinate system with different tilt angles.
Optionally, the first sample subset includes a first measuring plate and a second measuring plate which are vertically arranged, and the arrangement directions of the first measuring plate and the second measuring plate are perpendicular to each other.
Optionally, a portion of the second subset of samples is perpendicular to the measuring plane of the second measuring plate and is disposed obliquely to the measuring plane of the first measuring plate, and another portion of the second subset of samples is perpendicular to the measuring plane of the first measuring plate and is disposed obliquely to the measuring plane of the second measuring plate.
Optionally, the second subset comprises:
a third measuring plate, a fourth measuring plate, a fifth measuring plate, a sixth measuring plate, a seventh measuring plate, an eighth measuring plate, a ninth measuring plate and a tenth measuring plate which are perpendicular to the measuring surface of the second measuring plate and are obliquely arranged at 30 degrees, 45 degrees, 60 degrees, 75 degrees, 105 degrees, 120 degrees, 135 degrees and 150 degrees with the measuring surface of the first measuring plate respectively;
and the eleventh measuring plate, the twelfth measuring plate, the thirteenth measuring plate, the fourteenth measuring plate, the fifteenth measuring plate and the sixteenth measuring plate are perpendicular to the measuring surface of the first measuring plate and are obliquely arranged at angles of 30 degrees, 45 degrees, 60 degrees, 75 degrees, 105 degrees, 120 degrees, 135 degrees and 150 degrees with the measuring surface of the second measuring plate respectively.
Optionally, the measurement cartridge sample set comprises: a third sample subset of a cylindrical inner wall surface whose axis is perpendicular to the bottom plate and a fourth sample subset of a plurality of cylindrical inner wall surfaces whose axes are inclined at different angles are provided.
Optionally, the axis of a portion of the fourth subset of samples is parallel to the measurement plane of the second measurement plate and inclined to the measurement plane of the first measurement plate;
the axis of the other part of the fourth subset of samples is parallel to the measuring plane of the first measuring plate and inclined to the measuring plane of the second measuring plate.
Optionally, the third subset of samples comprises:
the axis of the first measuring cylinder is vertical to the bottom plate;
the axis of the second measuring tube is parallel to the measuring surface of the second measuring plate, and the second measuring tube, the third measuring tube, the fourth measuring tube, the fifth measuring tube, the sixth measuring tube and the seventh measuring tube are obliquely arranged at angles of 45 degrees, 60 degrees, 75 degrees, 105 degrees, 120 degrees and 135 degrees with the measuring surface of the first measuring plate;
an eighth measuring cylinder, a ninth measuring cylinder, a tenth measuring cylinder, an eleventh measuring cylinder, a twelfth measuring cylinder and a thirteenth measuring cylinder, the axes of which are parallel to the measuring surface of the first measuring plate and are obliquely arranged at 45 degrees, 60 degrees, 75 degrees, 105 degrees, 120 degrees and 135 degrees with the measuring surface of the second measuring plate.
The embodiment of the invention also provides a comprehensive error calibration method of the machine tool in-situ detection system, which comprises the following steps:
driving a machine tool in-situ detection system to perform coordinate measurement of multiple measurement points on the comprehensive error calibration device, wherein the multiple measurement points comprise multiple measurement points obtained by measuring on a measurement surface provided by the measurement plate sample set and multiple measurement points obtained by measuring on the inner wall surface of a cylindrical shape provided by the measurement cylinder sample set;
performing plane fitting and cylindrical surface fitting based on the measurement coordinates of the multiple measurement points, and calculating the flatness and the cylindricity;
driving a three-coordinate measuring machine to measure the standard coordinates of the multiple measuring points obtained by the comprehensive error calibration device;
performing plane fitting and cylindrical surface fitting based on the standard coordinates of the multiple measuring points, and calculating the flatness and the cylindricity;
comparing the measured coordinates with the standard coordinates, and comparing the flatness and cylindricity calculated based on the measured coordinates with the flatness and cylindricity calculated based on the standard coordinates to determine an error;
and evaluating the comprehensive error of the in-situ detection system of the machine tool by taking the determined error as an evaluation parameter.
Optionally, measuring the coordinate points of the measurement plane of the plate sample set includes: and coordinate points measured by the main shaft at a plurality of uniformly distributed measuring points on the measuring surface.
Optionally, the plurality of measurement points for measuring the cylindrical inner wall surface of the cylinder sample set include measurement points measured at intersections of cross sections of two different position points in the axial direction and the inner wall surface, and each intersection includes: and the main shaft is arranged at a coordinate point measured by a plurality of uniformly distributed measuring points at the intersection line.
According to the technical scheme, the comprehensive error calibration device of the machine tool in-situ detection system is provided with the plurality of inclination measurement surfaces and the inclination measurement inner holes which are arranged in advance, reference surfaces with different inclination angles are provided for calibration of the in-situ detection system, and the device is compact in structure and small in occupied volume.
Drawings
The following drawings are only schematic illustrations and explanations of the present invention, and do not limit the scope of the present invention.
Fig. 1 is a schematic diagram of a comprehensive error calibration device of a machine tool in-situ detection system according to an embodiment of the invention.
Fig. 2 is a top view of a comprehensive error calibration device of the in-situ machine tool detection system according to the embodiment of the invention.
Fig. 3 is a schematic view of direction a in fig. 2.
Fig. 4 is a schematic view of direction B in fig. 2.
Fig. 5 is a schematic view of fig. 2 taken along direction C.
Fig. 6 is a schematic view of fig. 2 from direction D.
Fig. 7 is a schematic view of fig. 2 from direction E.
Fig. 8 is a schematic view of fig. 2 from direction F.
Fig. 9 is a schematic view of fig. 2 from direction G.
Fig. 10 is a schematic view of fig. 2 from direction H.
Wherein, 1-a bottom plate;
2-measuring the plate;
3-a measuring cylinder;
201-first measuring plate, 202-second measuring plate, 203-third measuring plate, 204-fourth measuring plate, 205-fifth measuring plate, 206-sixth measuring plate, 207-seventh measuring plate, 208-eighth measuring plate, 209-ninth measuring plate, 210-tenth measuring plate,
211-eleventh measuring plate, 212-twelfth measuring plate, 213-thirteenth measuring plate, 214-fourteenth measuring plate, 215-fifteenth measuring plate, 216-sixteenth measuring plate, 217-seventeenth measuring plate, 218-eighteenth measuring plate;
301-first, 302-second, 303-third, 304-fourth, 305-fifth, 306-sixth, 307-seventh, 308-eighth, 309-ninth, 310-tenth, 311-eleventh, 312-twelfth, 313-thirteenth measuring cartridges;
the included angle between alpha 1-the third measuring plate and the bottom plate, the included angle between alpha 2-the fourth measuring plate and the bottom plate, the included angle between alpha 3-the fifth measuring plate and the bottom plate, the included angle between alpha 4-the sixth measuring plate and the bottom plate, the included angle between alpha 5-the seventh measuring plate and the bottom plate, the included angle between alpha 6-the eighth measuring plate and the bottom plate, the included angle between alpha 7-the ninth measuring plate and the bottom plate, the included angle between alpha 8-the tenth measuring plate and the bottom plate, the included angle between alpha 9-the eleventh measuring plate and the bottom plate, the included angle between alpha 10-the twelfth measuring plate and the bottom plate, the included angle between alpha 11-the thirteenth measuring plate and the bottom plate, the included angle between alpha 12-the fourteenth measuring plate and the bottom plate, the included angle between alpha 13-the fifteenth measuring plate and the bottom plate, the included angle between alpha 14-the sixteenth measuring plate and the bottom plate, the included angle between alpha 15, The included angle between the alpha 16-eighteenth measuring plate and the bottom plate;
the included angle of the axis of the beta 1-second measuring cylinder and the bottom plate, the included angle of the axis of the beta 2-third measuring cylinder and the bottom plate, the included angle of the axis of the beta 3-fourth measuring cylinder and the bottom plate, the included angle of the axis of the beta 4-fifth measuring cylinder and the bottom plate, the included angle of the axis of the beta 5-sixth measuring cylinder and the bottom plate, the included angle of the axis of the beta 6-seventh measuring cylinder and the bottom plate, the included angle of the axis of the beta 7-eighth measuring cylinder and the bottom plate, the included angle of the axis of the beta 8-ninth measuring cylinder and the bottom plate, the included angle of the axis of the beta 9-tenth measuring cylinder and the bottom plate, the included angle of the axis of the beta 10-eleventh measuring cylinder and the bottom plate, the included angle of the axis of the beta 11-twelfth measuring cylinder and the bottom plate, and the included angle of the axis of the beta.
Detailed Description
In order to more clearly understand the technical features, objects, and effects of the present invention, embodiments of the present invention will now be described with reference to the accompanying drawings, in which like reference numerals refer to like parts throughout.
"exemplary" means "serving as an example, instance, or illustration" herein, and any illustration, embodiment, or steps described as "exemplary" herein should not be construed as a preferred or advantageous alternative.
For the sake of simplicity, the drawings are only schematic representations of the parts relevant to the invention, and do not represent the actual structure of the product. In addition, in order to make the drawings concise and understandable, components having the same structure or function in some of the drawings are only schematically illustrated or only labeled.
In this document, "upper", "lower", "front", "rear", "left", "right", and the like are used only to indicate relative positional relationships between relevant portions, and do not limit absolute positions of the relevant portions.
In this document, "first", "second", and the like are used only for distinguishing one from another, and do not indicate the degree and order of importance, the premise that each other exists, and the like.
In this context, "equal", "same", etc. are not strictly mathematical and/or geometric limitations, but also include tolerances as would be understood by a person skilled in the art and allowed for manufacturing or use, etc. Unless otherwise indicated, numerical ranges herein include not only the entire range within its two endpoints, but also several sub-ranges subsumed therein.
In order to solve the technical problem that the error of the machine tool in-situ detection system in the prior art cannot be calibrated, as shown in fig. 1 to 10, an embodiment of the present invention provides a comprehensive error calibration apparatus for a machine tool in-situ detection system, including:
a base plate 1, the base plate 1 having an upper surface and a lower surface;
the device comprises a measuring plate sample set 2, wherein the measuring plate sample set 2 is arranged on a bottom plate 1, and the measuring plate sample set 2 can be fixed on the upper surface of the bottom plate 1 or integrated;
the device comprises a measuring cylinder sample set 3, wherein the measuring cylinder sample set 3 is arranged on a bottom plate 1, and the measuring cylinder sample set 3 can be fixed on the upper surface of the bottom plate 1 or integrated;
the plurality of measuring plates in the measuring plate sample set 2 are different in inclination angle, the axis inclination angles of the plurality of measuring cylinders in the measuring cylinder sample set 3 are different, namely the measuring plate sample set 2 provides measuring surfaces with different inclination angles, and the measuring cylinder sample set 3 provides inner holes with different inclination angles.
In order to ensure the accuracy of the in-situ detection system, the in-situ detection system must be calibrated and compensated before the in-situ detection system is applied to measure the workpiece, and the accuracy of the in-situ detection system after calibration still needs to be evaluated, but no device specially used for calibrating the in-situ detection system exists in the prior art.
The comprehensive error calibration device of the machine tool in-situ detection system is provided with a plurality of preset inclination measurement surfaces and inclination measurement inner holes, provides reference surfaces with different inclination angles for calibration of the in-situ detection system, and is compact in structure and small in occupied volume.
In one example, the measurement plate sample set 2 comprises a first sample subset for defining a three-dimensional coordinate system together with the base plate 1, and a second sample subset for providing a plurality of measurement planes with different tilt angles in the three-dimensional coordinate system. The first sample subset and the base plate 1 form a three-dimensional coordinate system, namely the three-dimensional coordinate system of the calibration device, the side surface of the second sample subset has an inclination angle relative to the three-dimensional coordinate system, the measurement surfaces with different inclination angles can calibrate the measurement results of the in-situ detection system of the machine tool on workpieces with different inclination angles, and the more the measurement surfaces with different inclination angles, the more the inclination angle measurement results of the in-situ detection system can be calibrated.
Specifically, the first sample subset includes a first measurement board 201 and a second measurement board 202 disposed perpendicular to the base board 1, and the arrangement directions of the first measurement board 201 and the second measurement board 202 are perpendicular to each other, that is, two of the base board 1, the first measurement board 201, and the second measurement board 202 are perpendicular to each other, that is, the intersection line of the upper surface of the base board 1 and the outermost side of the first measurement board 201 and the outermost side of the second measurement board 202 constitutes the three-dimensional coordinate system of the measurement system.
One part of the second sample subset is perpendicular to the measuring plane of the second measuring plate 202 and is obliquely arranged with the measuring plane of the first measuring plate 201, and the other part of the second sample subset is perpendicular to the measuring plane of the first measuring plate 201 and is obliquely arranged with the measuring plane of the second measuring plate 202, so that it can be understood that the second sample subset is obliquely arranged with the bottom plate 1 because the bottom plate 1, the first measuring plate 201 and the second measuring plate 202 are mutually perpendicular in pairs. The measurement area is the area of the second sample subset which is obliquely opposite or obliquely facing away from the upper surface of the base plate 1. As can be seen from the drawings, the first measurement plate 201 and the second measurement plate 202 are located at the edge of the base plate 1 and are arranged perpendicular to the base plate 1, and the measurement surfaces of the first measurement plate 201 and the second measurement plate 202 are the outer surfaces thereof.
More specifically, the second subset includes:
a third measurement plate 203, a fourth measurement plate 204, a fifth measurement plate 205, a sixth measurement plate 206, a seventh measurement plate 207, an eighth measurement plate 208, a ninth measurement plate 209, and a tenth measurement plate 210 that are perpendicular to the measurement surface of the second measurement plate 202 and are inclined at 30 °, 45 °, 60 °, 75 °, 105 °, 120 °, 135 °, and 150 ° from the measurement surface of the first measurement plate 201, respectively;
the second measuring unit of the measuring plate 2 comprises: an eleventh measurement plate 211, a twelfth measurement plate 212, a thirteenth measurement plate 213, a fourteenth measurement plate 214, a fifteenth measurement plate 215, a sixteenth measurement plate 216, a seventeenth measurement plate 217, and an eighteenth measurement plate 218 that are perpendicular to the measurement plane of the first measurement plate 201 and are obliquely arranged at 30 °, 45 °, 60 °, 75 °, 105 °, 120 °, 135 °, and 150 ° to the measurement plane of the second measurement plate 202, respectively.
In one example, the measurement cylinder sample set 3 includes: a third sample subset of cylindrical inner wall surfaces whose axes are perpendicular to the bottom plate 1 and a fourth sample subset of a plurality of cylindrical inner wall surfaces whose axes are inclined at different angles are provided. The third subset of samples is arranged perpendicular, i.e. vertically, to the base plate 1 and the axis of the fourth subset of samples is arranged obliquely, i.e. the fourth subset of samples is inclined with respect to the base plate 1.
Specifically, the axis of a part of the fourth sample subset is parallel to the measurement plane of the second measurement plate 202 and inclined to the measurement plane of the first measurement plate 201;
the axis of another part of the fourth subset of samples is parallel to the measurement plane of the first measurement plate 201 and inclined to the measurement plane of the second measurement plate 202; while the axes of the fourth subset of samples are arranged obliquely to the upper surface of the base plate 1.
More specifically, the third sample subset includes a first measuring cylinder 301 whose axis is perpendicular to the base plate 1, and the first measuring cylinder 301 is parallel to both the measuring surface of the first measuring plate 201 and the measuring surface of the second measuring plate 202;
a second measuring cylinder 302, a third measuring cylinder 303, a fourth measuring cylinder 304, a fifth measuring cylinder 305, a sixth measuring cylinder 306 and a seventh measuring cylinder 307, the axes of which are parallel to the measuring surface of the second measuring plate 202 and are obliquely arranged at 45 °, 60 °, 75 °, 105 °, 120 ° and 135 ° with respect to the measuring surface of the first measuring plate 201; and
an eighth measuring cylinder 308, a ninth measuring cylinder 309, a tenth measuring cylinder 310, an eleventh measuring cylinder 311, a twelfth measuring cylinder 312, and a thirteenth measuring cylinder 313, whose axes are parallel to the measuring plane of the first measuring plate 201 and are inclined at 45 °, 60 °, 75 °, 105 °, 120 °, and 135 ° from the measuring plane of the second measuring plate 202.
The inclination angles of the measuring plate and the measuring cylinder in the above embodiments are only an example, and are not the only possible embodiments, and the error assessment of the machine tool in-situ detection system can be realized as long as the inclination angles of the measuring plate and the measuring cylinder are different. In the above example, α 1 is 30 °, α 2 is 45 °, α 3 is 60 °, α 4 is 75 °, α 5 is 75 °, α 6 is 60 °, α 7 is 45 °, α 8 is 30 °, α 9 is 75 °, α 10 is 60 °, α 11 is 45 °, α 12 is 30 °, α 13 is 30 °, α 14 is 45 °, α 15 is 60 °, α 16 is 75 °; β 1 is 45 °, β 2 is 60 °, β 3 is 75 °, β 4 is 75 °, β 5 is 60 °, β 6 is 45 °, β 7 is 75 °, β 8 is 60 °, β 9 is 45 °, β 10 is 45 °, β 11 is 60 °, β 12 is 75 °.
The embodiment of the invention also provides an error calibration method for the in-situ detection system of the machine tool, which comprises the following steps:
s0: adjusting a machine tool spindle, wherein a measuring head arranged on the spindle measures the upper surface of the bottom plate 1, the measuring surface of the first measuring plate 201 and the measuring surface of the second measuring plate 202, and determining a three-dimensional coordinate system in the measuring process; before the measurement process is started, the error evaluation device of the in-situ machine tool detection system is placed on a workbench, and a high-precision measurement instrument is used for ensuring that one outer side surface of a bottom plate 1 of the device is parallel to an X axis of a machine tool, namely, the three-dimensional coordinate system of the device and the three-dimensional coordinate system in the machine tool are determined to be related, specifically, the coordinate axis direction of the three-dimensional coordinate system of the device is the same as the coordinate axis direction of the three-dimensional coordinate system in the machine tool, when the coordinate axis direction of the three-dimensional coordinate system in the machine tool is the same as the coordinate axis direction of the three-dimensional coordinate system of the device, a main shaft of the machine tool; the high-precision measuring instrument can be a dial indicator; the Z axis is the direction of the axis of the rotation of the cutter of the machine tool, the X axis and the Y axis are respectively the directions vertical to the Z axis, the A axis is the direction of the rotation around the X axis, the C axis is the direction of the rotation around the Z axis, and in the specific measurement process, the coordinate measured by the machine tool is measured by taking the three-dimensional coordinate system of the calibration device as the reference;
s1: and driving the machine tool in-situ detection system to perform coordinate measurement of multiple measurement points in the error calibration device, specifically, the measurement can be performed by a measuring head of the in-situ detection system, which is installed on the main shaft. The multiple measurement points include a plurality of measurement points measured on a measurement surface provided by the measurement plate sample set 2 and a plurality of measurement points measured on a cylindrical inner wall surface provided by the measurement cylinder sample set 3;
in one example, the steps specifically include:
s101: driving the spindle of the machine tool to rotate a certain angle along the axis A and a certain angle along the axis C, so that the measuring head arranged on the spindle is parallel to the measuring surface of a certain measuring plate, such as the fifth measuring plate 205, the spindle rotates 30 degrees along the axis A and rotates 90 degrees along the axis C, and the measuring head is parallel to the measuring surface of the fifth measuring plate 205; a translational moving probe for keeping the probe parallel to the measuring surface, and performing multi-coordinate measurement on the measuring surface of the measuring plate by the probe to obtain measurement of multiple coordinate points of the open angle surface and the closed angle surface of the measuring surface, such as four coordinate points P of the open angle surfacekij1(x1,y1,z1)、Pkij2(x2,y2,z2)、Pkij3(x3,y3,z3)、Pkij4(x4,y4,z4) And four coordinate points P of the closed angle surfacebij1(x1,y1,z1),Pbij2(x2,y2,z2),Pbij3(x3,y3,z3),Pbij4(x4,y4,z4);
After the measuring head moves to a measuring surface parallel to a certain measuring plate, the measuring head measures the measuring surface along a direction perpendicular to the measuring surface. The measuring head is parallel to the measuring surface of the measuring plate, so that the interference between the measuring surface and the measuring head can be avoided.
In the measuring process, the rotating angle of the main shaft determines a corresponding measuring plate, the main shaft can be moved up and down or left and right to ensure that the main shaft does not rotate, but the measuring head can simultaneously realize measurement on the angle opening surface and the angle closing surface, and the measured positions of the angle opening surface and the angle closing surface correspond to each other along the thickness direction of the measuring plate.
S102: the main shaft of the machine tool is driven to rotate a certain angle along the axis A and rotate a certain angle along the axis C, so that the measuring head arranged on the main shaft is parallel to the measuring surface of a certain measuring plate. Specifically, the main shaft of the machine tool is driven to rotate by 0 degrees, 15 degrees, 30 degrees, 45 degrees and 60 degrees respectively along the axis A, and rotate by 0 degrees, 90 degrees, 180 degrees and 270 degrees respectively along the axis C. Through the rotation of the main shaft along the axis A and the axis C, a main shaft measuring head is respectively parallel to the measuring surfaces of a plurality of different measuring plates, and four coordinate points of an open angle surface and a closed angle surface of each measuring plate are measured; it can be understood that each measuring plate respectively corresponds to the a axis rotating by a certain angle and the C axis rotating by a certain angle, the angle rotated by the a axis corresponds to the measuring plates with different inclination degrees, and the angle rotated by the C axis corresponds to the measuring plates with different inclination directions.
S103: the spindle of the machine tool is driven to rotate by a certain angle along the axis A and a certain angle along the axis C, so that a measuring head arranged on the spindle is parallel to a certain measuring point of a certain measuring cylinder, such as a fifth measuring cylinder 305, the spindle rotates by 15 degrees along the axis A and rotates by 90 degrees along the axis C, coordinate measurement is carried out on the inner wall surface of the measuring cylinder, coordinate points of two parallel circular rings of the inner wall surface of the measuring cylinder can be obtained by moving the measuring head in a translation manner, four coordinate points are taken by each circular ring, and eight coordinate points P are obtained in totalhij1(x1,y1,z1),Phij2(x2,y2,z2),Phij3(x3,y3,z3),Phij4(x4,y4,z4)、Phij5(x5,y5,z5),Phij6(x6,y6,z6),Phij7(x7,y7,z7),Phij8(x8,y8,z8);
S104: the machine tool spindle is driven to rotate along the axis A, specifically, the spindle rotates by 0 degrees, 15 degrees, 30 degrees and 45 degrees along the axis A, in the rotating process of the axis A, the spindle measuring heads are respectively parallel to the inner wall surfaces of different measuring cylinders, and eight coordinate points of the inner wall surface of each measuring cylinder are measured.
S2: performing plane fitting and cylindrical surface fitting based on the measurement coordinates of the multiple measurement points, and calculating the flatness and the cylindricity;
specifically, the following step S201 may be included: the plane is fitted using the least squares method.
Specifically, n measurement points P (x) on one planei,yi,zi) I is 0,1, …, n-1, i.e. the coefficients of the plane equation are found which minimize the following equation:
Figure BDA0001909868410000081
that is, solving the linear equation:
Figure BDA0001909868410000082
obtaining a fitting plane z ═ a0x+a1y+a2
S202: the flatness of the plane is calculated.
Specifically, the distances from all the measurement points to the fitting plane are obtained, and the difference between the maximum distance and the minimum distance is the flatness of the plane.
S203: and fitting the cylindrical surface by using a least square method.
Specifically, n measurement points P (x) on the inner wall surface of one measurement cylinderi,yi,zi) I is 0, 1.., n-1 is fitted to a circle, i.e., the coefficients of a circular equation that minimizes the following equation are found:
Figure BDA0001909868410000091
that is, solving the system of equations:
Figure BDA0001909868410000092
Figure BDA0001909868410000093
Figure BDA0001909868410000094
obtaining a fitting circle x2+y2+ax+by+c=0
The line of the centers of the two fitting circles on the cylindrical surface is the center line of the fitting cylinder, the average value of the diameters of the two circles is the diameter of the fitting cylinder, and the fitting cylindrical surface can be obtained through the center line of the fitting cylinder and the diameter of the fitting cylinder;
s204: the cylindricity of the inner wall surface of the measuring cylinder is calculated.
Specifically, the distances between all the measurement points and the fitting cylindrical surface are found, wherein the difference between the maximum distance and the minimum distance is the cylindricity of the cylindrical surface.
According to the actual operation requirement, if the accuracy of the in-situ detection system for thickness measurement needs to be determined, the following steps can be added: s205: and (3) calculating the distance between the measuring points at the corresponding positions of the closed angle surface and the open angle surface of the same measuring plate, namely the thickness of the measuring plate.
S3: driving a three-coordinate measuring machine to measure and obtain the standard coordinates of the multiple measuring points in the error calibration device, wherein the precision of the three-coordinate measuring machine is higher than that of an in-situ detection system, so that the coordinates measured by the three-coordinate measuring machine are considered as the standard coordinates, namely the in-situ detection system of the machine tool is calibrated by the three-coordinate measuring machine; during calibration, the three-coordinate measuring machine measures along the same measuring path of the in-situ detection system in the step S1, so that the paths of the three-coordinate measuring machine and the in-situ detection system of the machine tool are the same, and the positions of the measured measuring points are completely the same, so that the measured result has comparability;
s4: performing plane fitting and cylindrical surface fitting based on the standard coordinates of the multiple measuring points, and calculating the flatness and the cylindricity; the fitting of the plane and the cylindrical surface can adopt the least square method, and can also adopt other methods, a more high-precision fitting system in a specific three-coordinate measuring machine is used for fitting to obtain a fitting plane and a cylindrical surface, and the planeness and the cylindricity can be obtained by calculation by the same method as that in the step S2;
this step can also measure the thickness of the measured plate according to the method in the above step S2, as required by the actual calibration situation.
S5: comparing the measured coordinates with the standard coordinates, and comparing the flatness and cylindricity calculated based on the measured coordinates with the flatness and cylindricity calculated based on the standard coordinates to determine an error;
the errors of the in-situ detection system of the machine tool comprise positioning and measuring head errors and measurement characteristic calculation method errors, and the measurement result of the three-coordinate measuring machine is taken as a standard value because the three-coordinate measuring machine has higher precision.
The evaluation parameter of the positioning and measuring head error is the sum of the coordinate measured by the in-situ detection system and the coordinate distance measured by the three-coordinate measuring machine;
specifically, the coordinates of each measuring point on the three-coordinate measuring machine are
Figure BDA0001909868410000101
In-situ detection of the coordinates of each measurement point as
Figure BDA0001909868410000102
The evaluation parameters of the positioning and measuring head errors are
Figure BDA0001909868410000103
The evaluation parameters of the errors of the measurement characteristic calculation method are the absolute values of the quantity sum of the difference value of the flatness measured by the in-situ detection system and the flatness measured by the three-coordinate measuring machine and the difference value of the cylindricity measured by the in-situ detection system and the cylindricity measured by the three-coordinate measuring machine.
Specifically, the three-coordinate measuring machine is used for measuring the planeness of the inclined plane, and the three-coordinate measuring machine is used for measuring the planeness of the inclined plane
Figure BDA0001909868410000104
In situ detectionMeasuring flatness of
Figure BDA0001909868410000105
In-situ detection of flatness errorsdiComprises the following steps:
Figure BDA0001909868410000106
the three-coordinate measuring machine is arranged to measure the cylindricity of the inclined hole into
Figure BDA0001909868410000107
In-situ detection of the cylindricity of the inclined hole
Figure BDA0001909868410000108
In-situ detection of cylindricity errorriComprises the following steps:
Figure BDA0001909868410000109
the absolute value of the sum of the numbers of the in-situ detection flatness error and the in-situ detection cylindricity error is as follows:
Figure BDA00019098684100001010
in addition, if the thickness measurement accuracy of the in-situ detection system needs to be evaluated, the thickness measurement error of the in-situ detection system is the difference between the thickness of the measured plate measured by the in-situ detection system and the thickness of the measured plate measured by the three-coordinate measuring machine.
S6: and determining the effectiveness of the compensation method of the in-situ detection system by using the determined error as an evaluation parameter of the comprehensive error of the in-situ detection system of the machine tool.
It can be understood that, after the errors in step S5 are determined, it is determined whether the accuracy of the in-situ detection system reaches the expected threshold according to the errors, and if the accuracy of the in-situ detection system exceeds the expected threshold, the in-situ detection system needs to be adjusted, which may specifically be a measurement head error compensation method, a machine tool positioning error compensation method, and a measurement characteristic calculation method for adjusting the in-situ detection system, and after the adjustment is completed, the above steps S1-S5 are repeated to calibrate the combined error of the in-situ detection system again until the accuracy of the in-situ detection system reaches the expected.
It should be understood that although the present description has been described in terms of various embodiments, not every embodiment includes only a single embodiment, and such description is for clarity purposes only, and those skilled in the art will recognize that the embodiments described herein can be combined as a whole to form other embodiments as would be understood by those skilled in the art.
The above-listed detailed description is only a specific description of a possible embodiment of the present invention and is not intended to limit the scope of the present invention, and equivalent embodiments or modifications such as combinations, divisions or repetitions of the features without departing from the technical spirit of the present invention are included in the scope of the present invention.

Claims (11)

1. The utility model provides a comprehensive error calibration device of lathe normal position detecting system which characterized in that includes:
a base plate (1);
a measurement plate sample set (2), the measurement plate sample set (2) being mounted to the base plate (1);
a measurement cylinder sample set (3), the measurement cylinder sample set (3) being mounted to the base plate (1);
the plurality of measuring plates in the measuring plate sample set (2) are different in inclination angle, and the plurality of measuring cylinders in the measuring cylinder sample set (3) are different in axial inclination angle.
2. A combined error calibration arrangement according to claim 1, characterized in that the set of measurement plate samples (2) comprises a first subset of samples for defining a three-dimensional coordinate system together with the base plate (1), and a second subset of samples for providing a plurality of measurement planes with different tilt angles in the three-dimensional coordinate system.
3. A comprehensive error calibration device according to claim 2, characterized in that the first sample subset comprises a first measurement board (201) and a second measurement board (202) which are vertically arranged, and the arrangement directions of the first measurement board (201) and the second measurement board (202) are perpendicular to each other.
4. A combined error calibration device according to claim 3, characterized in that a part of the second subset of samples is arranged perpendicular to the measuring plane of the second measuring plate (202) and inclined to the measuring plane of the first measuring plate (201), and another part of the second subset of samples is arranged perpendicular to the measuring plane of the first measuring plate (201) and inclined to the measuring plane of the second measuring plate (202).
5. The integrated error calibration apparatus of claim 4, wherein the second subset of samples comprises:
a third measuring plate (203), a fourth measuring plate (204), a fifth measuring plate (205), a sixth measuring plate (206), a seventh measuring plate (207), an eighth measuring plate (208), a ninth measuring plate (209) and a tenth measuring plate (210) which are perpendicular to the measuring surface of the second measuring plate (202) and are obliquely arranged at 30 °, 45 °, 60 °, 75 °, 105 °, 120 °, 135 ° and 150 ° with respect to the measuring surface of the first measuring plate (201);
an eleventh measuring plate (211), a twelfth measuring plate (212), a thirteenth measuring plate (213), a fourteenth measuring plate (214), a fifteenth measuring plate (215), and a sixteenth measuring plate (216) which are perpendicular to the measuring surface of the first measuring plate (201) and are obliquely arranged at 30 °, 45 °, 60 °, 75 °, 105 °, 120 °, 135 °, and 150 ° with respect to the measuring surface of the second measuring plate (202), respectively.
6. The integrated error calibration apparatus according to claim 3,
the measurement cylinder sample set (3) comprises: a third sample subset of a cylindrical inner wall surface whose axis is perpendicular to the bottom plate (1) and a fourth sample subset of a plurality of cylindrical inner wall surfaces whose axes are inclined at different angles are provided.
7. The integrated error calibration device according to claim 6, wherein the axis of a portion of the fourth sample subset is parallel to the measurement plane of the second measurement plate (202) and inclined to the measurement plane of the first measurement plate (201);
the axis of the other part of the fourth subset of samples is parallel to the measuring plane of the first measuring plate (201) and inclined to the measuring plane of the second measuring plate (202).
8. A combined error calibration device according to claim 7, characterized in that said third subset of samples comprises a first measuring cylinder (301) having an axis perpendicular to said base plate (1);
the fourth sample subset comprises a second measuring cylinder (302), a third measuring cylinder (303), a fourth measuring cylinder (304), a fifth measuring cylinder (305), a sixth measuring cylinder (306) and a seventh measuring cylinder (307), wherein the axes of the second measuring cylinder (302), the third measuring cylinder, the fourth measuring cylinder (304), the fifth measuring cylinder (305), the sixth measuring cylinder (306) and the seventh measuring cylinder are parallel to the measuring surface of the second measuring plate (202) and are obliquely arranged at 45 degrees, 60 degrees, 75 degrees, 105 degrees, 120 degrees and 135 degrees with the measuring surface of the first measuring plate (201);
an eighth measuring cylinder (308), a ninth measuring cylinder (309), a tenth measuring cylinder (310), an eleventh measuring cylinder (311), a twelfth measuring cylinder (312) and a thirteenth measuring cylinder (313) the axes of which are parallel to the measuring surface of the first measuring plate (201) and are obliquely arranged at 45 °, 60 °, 75 °, 105 °, 120 ° and 135 ° to the measuring surface of the second measuring plate (202).
9. A comprehensive error calibration method of a machine tool in-situ detection system is characterized by comprising the following steps:
driving a machine tool in-situ detection system to perform coordinate measurement of multiple measurement points in the integrated error calibration device as claimed in any one of claims 1 to 8, wherein the multiple measurement points include multiple measurement points measured on the measurement surface provided by the measurement plate sample set (2) and multiple measurement points measured on the cylindrical inner wall surface provided by the measurement cylinder sample set (3);
performing plane fitting and cylindrical surface fitting based on the measurement coordinates of the multiple measurement points, and calculating the flatness and the cylindricity;
driving a three-coordinate measuring machine to measure the standard coordinates of the multiple measuring points obtained by the comprehensive error calibration device according to any one of claims 1-8;
performing plane fitting and cylindrical surface fitting based on the standard coordinates of the multiple measuring points, and calculating the flatness and the cylindricity;
comparing the measured coordinates with the standard coordinates, and comparing the flatness and cylindricity calculated based on the measured coordinates with the flatness and cylindricity calculated based on the standard coordinates to determine an error;
and evaluating the comprehensive error of the in-situ detection system of the machine tool by using the determined error evaluation as an evaluation parameter.
10. A comprehensive error calibration method according to claim 9, characterized in that the coordinate points of the measurement surface of the measurement plate sample set (2) comprise: and coordinate points measured by a plurality of uniformly distributed measuring points of the machine tool spindle on the measuring surface.
11. The integrated error calibration method according to claim 10, wherein the plurality of measurement points of the cylindrical inner wall surface of the measurement cylinder sample set (3) include measurement points measured at intersections of cross sections of two different axial position points with the inner wall surface, and each intersection includes: and the main shaft is arranged at a coordinate point measured by a plurality of uniformly distributed measuring points at the intersection line.
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Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006263803A (en) * 2005-03-25 2006-10-05 Sumitomo Heavy Ind Ltd Laser beam machining method and equipment
CN101354230A (en) * 2007-07-26 2009-01-28 瑞尼斯豪公司 Measurement probe systems for co-ordinate positioning apparatus
CN103134451A (en) * 2011-11-30 2013-06-05 鸿富锦精密工业(深圳)有限公司 Three-coordinate measuring machine three-axis perpendicularity error compensation system and method
CN103447884A (en) * 2013-08-02 2013-12-18 西安交通大学 Numerical control machine tool translational shaft geometric error measuring device and measuring and identifying method
CN105136031A (en) * 2015-08-25 2015-12-09 华中科技大学 Five-axis linkage machine tool rotation shaft geometric error continuous measurement method
CN106524905A (en) * 2016-10-11 2017-03-22 北京工业大学 Four-shaft machine tool calibration method based on multi-station measurement of laser tracker
CN107234487A (en) * 2017-05-31 2017-10-10 天津大学 Moving component multi-parameter detecting method based on combinatorial surface type standard
CN107246852A (en) * 2017-07-25 2017-10-13 歌尔股份有限公司 Measurement scaling method, device and angle-adjusting mechanism based on angle-adjusting mechanism

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN2115516U (en) * 1992-03-21 1992-09-09 欧阳健飞 T-shape machine tool error tester
CN2169847Y (en) * 1993-03-05 1994-06-22 欧阳健飞 Combined ball row testing apparatus
CN201589588U (en) * 2009-09-18 2010-09-22 寿震森 Detection table for detecting shape and position error of mechanical parts
GB201003363D0 (en) * 2010-03-01 2010-04-14 Renishaw Plc Measurement method and apparatus
CN106141814B (en) * 2016-08-04 2017-12-29 天津大学 The detection of Digit Control Machine Tool translation shaft geometric error and discrimination method based on LaserTRACER

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006263803A (en) * 2005-03-25 2006-10-05 Sumitomo Heavy Ind Ltd Laser beam machining method and equipment
CN101354230A (en) * 2007-07-26 2009-01-28 瑞尼斯豪公司 Measurement probe systems for co-ordinate positioning apparatus
CN103134451A (en) * 2011-11-30 2013-06-05 鸿富锦精密工业(深圳)有限公司 Three-coordinate measuring machine three-axis perpendicularity error compensation system and method
CN103447884A (en) * 2013-08-02 2013-12-18 西安交通大学 Numerical control machine tool translational shaft geometric error measuring device and measuring and identifying method
CN105136031A (en) * 2015-08-25 2015-12-09 华中科技大学 Five-axis linkage machine tool rotation shaft geometric error continuous measurement method
CN106524905A (en) * 2016-10-11 2017-03-22 北京工业大学 Four-shaft machine tool calibration method based on multi-station measurement of laser tracker
CN107234487A (en) * 2017-05-31 2017-10-10 天津大学 Moving component multi-parameter detecting method based on combinatorial surface type standard
CN107246852A (en) * 2017-07-25 2017-10-13 歌尔股份有限公司 Measurement scaling method, device and angle-adjusting mechanism based on angle-adjusting mechanism

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
数控机床综合几何误差的;李小力;《中国博士学位论文全文数据库 工程科技Ⅰ辑》;20080315;正文第48页、图3.11 *
精密加工中圆柱度在机检测关键技术;贝广霞;《山东大学学报》;20071031;正文第65-67页 *

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