阅读说明：本技术 一种基于标准件的五轴fdm三维打印机转台旋转轴的测定方法 (Method for measuring rotating shaft of five-axis FDM three-dimensional printer turntable based on standard component ) 是由 刘浩 刘睿 贾和平 曹明 于 2019-08-30 设计创作，主要内容包括：本发明公开了一种基于标准件的五轴FDM三维打印机转台旋转轴的测定方法,标准件包括设置于底板上的两行平行的若干个锥形单元形成的阵列,其中行方向的若干个锥形单元顶点形成的直线和每组两个在列方向上对应的锥形单元顶点形成的直线相互垂直,每个锥形单元包括一个主锥和一个支锥,支锥的轴线和主锥的轴线形成夹角,各个支锥与其相对应的主锥之间形成的夹角角度相同,支锥与其对应的主锥顶点的连线在列方向上；本发明用于一些打印塑料样件的FDM三维打印机,在其采用低端转台的情况下,测定其转轴在机器坐标系中的对应的直线方程。(The invention discloses a method for measuring a rotating shaft of a five-axis FDM three-dimensional printer turntable based on a standard component, wherein the standard component comprises an array formed by two parallel rows of conical units arranged on a bottom plate, straight lines formed by the vertexes of the conical units in the row direction are mutually vertical to straight lines formed by the vertexes of each group of two conical units corresponding to the column direction, each conical unit comprises a main cone and a supporting cone, the axial line of each supporting cone and the axial line of the main cone form an included angle, the included angle formed between each supporting cone and the corresponding main cone is the same, and the connecting line of the supporting cone and the corresponding main cone vertex is in the column direction; the invention is used for FDM three-dimensional printers for printing plastic samples, and measures corresponding linear equations of rotating shafts of the FDM three-dimensional printers in a machine coordinate system under the condition that the FDM three-dimensional printers adopt a low-end turntable.)

1. A method for measuring a rotating shaft of a five-axis FDM three-dimensional printer turntable based on a standard component is characterized by comprising the following steps of:

the standard component comprises an array formed by a plurality of conical units which are arranged on a bottom plate in parallel in two rows, wherein straight lines formed by vertexes of the conical units in the row direction are mutually vertical to straight lines formed by vertexes of two conical units corresponding to each other in the column direction in each group, each conical unit comprises a main cone and a branch cone, the axes of the branch cones form included angles with the axis of the main cone, the included angles formed between each branch cone and the corresponding main cone are the same, and the connecting lines of the branch cones and the vertexes of the corresponding main cones are in the column direction,

in a coordinate system of the printer machine tool, when an operator faces the printer machine tool, the horizontal direction of the printer is an x axis, the horizontal right direction is a positive direction, the vertical upward direction of a nozzle is a z axis, the upward direction is positive, the direction of the y axis is determined by using a right-hand rule, an A axis of the printer rotates around the x axis, and a C axis of the printer rotates around the z axis;

the measurement method is as follows: installing the mounting disc on a rotary table of a printer, installing the standard parts on the mounting disc in a grading manner for measurement, wherein the included angle formed by the row direction of the standard parts installed each time and the x axis of a machine tool coordinate system of the printerInstead, the print nozzle is then moved so that the print nozzle is aligned with the cone cusp to measure the position of the primary cone apex of each cell of the standard,

fitting a linear equation of the row direction in a machine tool coordinate system line by line, averaging to obtain a row direction straight line of the standard part, and calculating an included angle between the row direction straight line and the positive direction of an x axis of the machine tool coordinate system

Calculating the position of the vertex of each cone in the machine coordinate system

rotate the C axis

Rotate the C axis

Fitting an A axis and a C axis according to the data and the optimization model so as to complete measurement;

optimization model

Wherein: m represents the total number of row-direction cones, n represents the total number of column-direction cones, when the C-axis rotates

2. The method for measuring the rotating shaft of the turntable of the five-shaft FDM three-dimensional printer based on the standard part as claimed in claim 1, wherein the method comprises the following steps: the standard component is arranged in the row direction, and the branch cone is positioned outside the corresponding main cone.

3. The method for measuring the rotating shaft of the turntable of the five-shaft FDM three-dimensional printer based on the standard part as claimed in claim 1, wherein the method comprises the following steps: the lower surface of the bottom plate of the standard component and the upper surface of the mounting disc are smooth and flat.

4. The method for measuring the rotating shaft of the turntable of the five-shaft FDM three-dimensional printer based on the standard part as claimed in claim 1, wherein the method comprises the following steps: all be provided with a plurality of bolt holes that correspond in position on the bottom plate of standard and the mounting disc, also be provided with the screw hole on the mounting disc, the bolt passes the detachable fixed connection of bolt hole on the bottom plate of standard and the mounting disc in proper order.

5. The method for measuring the rotating shaft of the turntable of the five-shaft FDM three-dimensional printer based on the standard part as claimed in claim 1, wherein the method comprises the following steps: the mounting disc and the rotary table of the printer are respectively provided with a plurality of bolt holes corresponding to each other in position, and the bolts sequentially penetrate through the mounting disc and the bolt holes in the rotary table of the printer to be detachably and fixedly connected.

6. The method for measuring the rotating shaft of the turntable of the five-shaft FDM three-dimensional printer based on the standard part as claimed in claim 1, wherein the method comprises the following steps: the rotary table of the printer is provided with a printing substrate, the printing substrate is detached from the rotary table of the printer during measurement, and then the mounting disc is mounted on the rotary table of the printer.

7. The method for measuring the rotating shaft of the turntable of the five-shaft FDM three-dimensional printer based on the standard part as claimed in claim 1, wherein the method comprises the following steps: the three standard components are different in that the included angles formed by the axes of the branch cones and the axis of the main cone are respectively 30 degrees, 60 degrees and 90 degrees.

8. The method for measuring the rotating shaft of the turntable of the five-shaft FDM three-dimensional printer based on the standard part as claimed in claim 1, wherein the method comprises the following steps: the number of the nozzles is 1 or more.

Technical Field

The invention belongs to the technical field of 3D printing, and particularly relates to a method for measuring a rotating shaft of a five-axis FDM three-dimensional printer turntable based on a standard component.

Background

The Fused Deposition Modeling (FDM) -based 3D printing technology is one of the traditional printing technologies in the 3D printing field, and is popular with numerous device developers and users due to the simple and easy realization of the principle of layer-by-layer stacking and molding of printing materials in a molten state, and can be used for printing various physical models and artware. However, since the FDM printer is typically used to print plastic prototypes, the manufacturing cost should not be too high.

Industrial-grade high-end turntables are not suitable for use in FDM printers for manufacturing plastic prototypes due to their high positioning accuracy, complex manufacturing and assembly processes, and high cost. The manufacturing process and the assembly process of the low-end rotary table are rough, so that the rotating geometric error of the low-end rotary table is large, and therefore in CAM software, an axis A and an axis C of the low-end rotary table in the FDM printer need to be used as spatial straight lines, and a workpiece rotates around the corresponding spatial straight lines, so that the positioning accuracy meeting the FDM three-dimensional printing requirement is obtained.

Therefore, for some FDM three-dimensional printers that print plastic prototypes, where they employ a low-end turret, it is necessary to determine the corresponding linear equations of their axes in the machine coordinate system.

Disclosure of Invention

The invention provides a method for measuring a rotating shaft of a five-axis FDM three-dimensional printer turntable based on a standard component, which aims to solve the problems in the prior art.

In order to achieve the purpose, the invention adopts the technical scheme that:

a method for measuring a rotating shaft of a five-axis FDM three-dimensional printer turntable based on a standard component comprises an array formed by two parallel conical units arranged on a bottom plate, wherein straight lines formed by vertexes of the conical units in the row direction are mutually vertical to straight lines formed by vertexes of conical units corresponding to each group in the column direction, each conical unit comprises a main cone and a branch cone, the axes of the branch cones form an included angle with the axis of the main cone, the included angle formed between each branch cone and the corresponding main cone is the same, and the connecting line of the branch cone and the corresponding main cone vertex is in the column direction,

in a coordinate system of the printer machine tool, when an operator faces the printer machine tool, the horizontal direction of the printer is an x axis, the horizontal right direction is a positive direction, the vertical upward direction of a nozzle is a z axis, the upward direction is positive, the direction of the y axis is determined by using a right-hand rule, an A axis of the printer rotates around the x axis, and a C axis of the printer rotates around the z axis;

the measurement method is as follows: installing the mounting disc on a rotary table of a printer, installing the standard parts on the mounting disc in a grading manner for measurement, wherein the included angle formed by the row direction of the standard parts installed each time and the x axis of a machine tool coordinate system of the printer

And if the difference is different, moving the printing nozzle to enable the printing nozzle to be aligned with the cone cusp to measure the position of the main cone vertex of each unit of the standard part, fitting a linear equation of the line direction in the machine tool coordinate system line by line, averaging to obtain a line direction straight line of the standard part, and calculating the included angle between the line direction straight line and the positive direction of the x axis of the machine tool coordinate system

Calculating the position of the vertex of each cone in the machine coordinate system

Wherein:_kthe number of the branch cone is shown,_i,jrespectively representing a row direction and a column direction;

rotate the C axis

An angle such that the row direction coincides with the x-axis positive direction; sequentially rotating the A shaft to form an included angle theta between the line direction branch cone and the main cone axis of each line_0,iSo that the axial lines of the row direction supporting cones of each row are coincided with the Z axis in the positive direction respectively through the theoryCalculating the theoretical position of each vertex after rotation by a formula

Wherein: p is a radical of_A,q_AAre two points on the A axis, p_C,q_CAre two points on the C-axis and,

is a matrix of rotations about the a-axis,

is a matrix of rotations about the c-axis,

is the initial position; respectively measuring the actual positions of the vertexes of the conical branches after rotation

Rotate the C axis

An angle such that the row direction coincides with the x-axis positive direction; sequentially rotating the A shaft to form an included angle theta between the line direction branch cone and the main cone axis of each line_1,iThe axial line of the row direction supporting cone of each row is coincided with the Z axis in the positive direction, and the theoretical position of each vertex after rotation is calculated through a theoretical formula respectively

Wherein:

is a matrix of rotations about the a-axis,

is a rotation matrix around the c-axis; respectively measuring the actual positions of the vertexes of the conical branches after rotation

Fitting an A axis and a C axis according to the data and the optimization model so as to complete measurement;

optimization model

Wherein:_mthe total number of the row-direction cones is shown,_nindicates the total number of column-direction cones when the C-axis rotates

Such that the row direction coincides with the x-axis forward direction; sequentially rotating the A shaft to form an included angle theta between the line direction branch cone and the main cone axis of each line_k,iThe axial line of the row direction supporting cone of each row is coincided with the Z axis in the positive direction, and the theoretical position of each vertex after rotation is calculated through a theoretical formula

Showing the actual position of each of the apex of the cones after rotation.

Preferably, the standard is located outside the corresponding main cone in the row direction.

Preferably, the lower surface of the base plate of the standard and the upper surface of the mounting plate are smooth and flat.

Preferably, a plurality of bolt holes corresponding to each other in position are formed in the bottom plate and the mounting disc of the standard component, threaded holes are also formed in the mounting disc, and the bolts sequentially penetrate through the bottom plate of the standard component and the bolt holes in the mounting disc to be detachably and fixedly connected.

Preferably, a plurality of bolt holes corresponding to each other in position are formed in the mounting disc and the turntable of the printer, and the bolts sequentially penetrate through the bolt holes in the mounting disc and the turntable of the printer to be detachably and fixedly connected.

Preferably, the printing substrate is mounted on the turntable of the printer, and during the measurement, the printing substrate is detached from the turntable of the printer, and then the mounting plate is mounted on the turntable of the printer.

Preferably, the standard parts are three, and the three standard parts are different in that the axes of the branch cones and the axis of the main cone form included angles of 30 degrees, 60 degrees and 90 degrees respectively.

Preferably, the number of the nozzles is 1 or more.

Compared with the prior art, the invention has the following beneficial effects:

the invention is used for FDM three-dimensional printers for printing plastic samples, and measures corresponding linear equations of rotating shafts of the FDM three-dimensional printers in a machine coordinate system under the condition that the FDM three-dimensional printers adopt a low-end turntable. Most of the existing methods for measuring the center of the turntable at the low end have low precision, so that the printing quality of workpieces is poor. The invention can greatly improve the measurement precision of the center of the machine tool, and the printed workpiece has higher quality.

Drawings

FIG. 1 is a schematic view of the construction of a standard of the present invention;

FIG. 2 is a schematic view of a 30 degree angle standard according to the present invention;

FIG. 3 is a schematic view of a 60 degree angle standard of the present invention;

FIG. 4 is a schematic view of a 90 degree angle standard of the present invention;

FIG. 5 is a top plan view of the assembly of the standard and mounting plate of the present invention;

FIG. 6 is a side view of the assembly of the standard and mounting plate of the present invention;

FIG. 7 is a perspective view of the assembly of the standard and mounting plate of the present invention;

FIG. 8 is a schematic view showing a state in which a standard component is mounted on the printer according to the present invention;

FIG. 9 is a side view of the standard of the present invention in a mounted state on the printer;

wherein: 1-standard part, 2-mounting plate, 3-bolt hole, 4-rotary table, 5-A shaft, 6-C shaft, 7-nozzle a, 8-nozzle b, 9-main cone, 10-branch cone and 11-bottom plate.

Detailed Description

The present invention will be further described with reference to the following examples.

As shown in fig. 1-9, a method for measuring a rotating shaft of a turntable of a five-axis FDM three-dimensional printer based on a standard component,

the standard component 1 comprises an array formed by two rows of parallel conical units arranged on a bottom plate 11, wherein straight lines formed by vertexes of the conical units in the row direction are mutually vertical to straight lines formed by vertexes of each group of two conical units corresponding to each other in the column direction, each conical unit comprises a main cone 9 and a supporting cone 10, the axes of the supporting cones form an included angle with the axis of the main cone, the included angle formed between each supporting cone and the corresponding main cone is the same, and the connecting lines of the supporting cones and the vertexes of the corresponding main cones are in the column direction,

in a coordinate system of the printer machine tool, when an operator faces the printer machine tool, the horizontal direction of the printer is an x axis, the horizontal direction is a positive right direction, the vertical upward direction of a nozzle is a z axis, the upward direction is positive, the direction of a y axis is determined by a right-hand rule, the direction which is perpendicular to the x axis and the z axis and points to the operator is the positive direction of the y axis, specifically, the printer is positioned on, the bottom of a rotary table 4 is provided with an A axis 5 which has the same position with the x axis, the rotary table 4 is also connected with a C axis 6 which has the same position with the z axis, the A axis 5 drives the rotary table 4 to rotate around the x axis, the C axis 6 drives the rotary table 4 to rotate around the z axis, and in essence, the A axis 5 and the C axis 6 drive a standard component 1 on a mounting disc 2 arranged on the rotary table;

the measurement method is as follows: installing the mounting disc on a rotary table of a printer, installing the standard parts on the mounting disc in a grading manner for measurement, wherein the included angle formed by the row direction of the standard parts installed each time and the x axis of a machine tool coordinate system of the printer

Different from (A)

Is a randomly placed angle), then the print nozzle is moved so that the print nozzle is aligned with the cone apex to measure the position of the primary cone apex of each cell of the standard,

fitting a linear equation of the machine tool coordinate system in the row direction line by line and averaging to obtain a row direction line of the standard component,calculating the included angle between the straight line in the row direction and the positive direction of the x axis of the machine tool coordinate system

Calculating the position of the vertex of each cone in the machine coordinate systemWherein:_kthe number of the branch cone is shown,_ij represents a row direction and a column direction, respectively;

rotate the C axis

An angle such that the row direction coincides with the x-axis positive direction; sequentially rotating the A shaft to form an included angle theta between the line direction branch cone and the main cone axis of each line_0,iThe axial line of the row direction supporting cone of each row is coincided with the Z axis in the positive direction, and the theoretical position of each vertex after rotation is calculated through a theoretical formula respectively

Wherein: p is a radical of_A,q_AAre two points on the A axis, p_C,q_CAre two points on the C-axis and,

is a matrix of rotations about the a-axis,is a matrix of rotations about the c-axis,

is the initial position; respectively measuring the actual positions of the vertexes of the conical branches after rotation

Rotate the C axis

Angle such that the row direction is aligned with the x-axisDirection superposition; sequentially rotating the A shaft to form an included angle theta between the line direction branch cone and the main cone axis of each line_1,iThe axial line of the row direction supporting cone of each row is coincided with the Z axis in the positive direction, and the theoretical position of each vertex after rotation is calculated through a theoretical formula respectively

Wherein:

is a matrix of rotations about the a-axis,is a rotation matrix around the c-axis; respectively measuring the actual positions of the vertexes of the conical branches after rotation

Fitting an A axis and a C axis according to the data and the optimization model so as to complete measurement;

optimization model

Wherein:_mthe total number of the row-direction cones is shown,_nindicates the total number of column-direction cones when the C-axis rotates

Such that the row direction coincides with the x-axis forward direction; sequentially rotating the A shaft to form an included angle theta between the line direction branch cone and the main cone axis of each line_k,iThe axial line of the row direction supporting cone of each row is coincided with the Z axis in the positive direction, and the theoretical position of each vertex after rotation is calculated through a theoretical formula

Showing the actual position of each of the apex of the cones after rotation.

As a preferred scheme, the standard component is in the direction of going, and the branch awl is located the owner awl outside rather than corresponding, and the lower surface of the bottom plate of standard component and the upper surface of mounting disc are all smooth and level, all are provided with a plurality of bolt holes that the position corresponds on the bottom plate of standard component and the mounting disc, also are provided with the screw hole on the mounting disc, and the bolt passes the detachable fixed connection of bolt hole on the bottom plate of standard component and the mounting disc in proper order.

As shown in fig. 2-4, the standard components are three types, and the three types of standard components are different in that the axes of the branch cones and the axis of the main cone form included angles of 30 degrees, 60 degrees and 90 degrees respectively.

As a preferred scheme, a plurality of bolt holes corresponding to each other in position are formed in the mounting disc and the rotary table of the printer, and bolts sequentially penetrate through the bolt holes in the mounting disc and the rotary table of the printer to be detachably and fixedly connected. The rotary table of the printer is provided with a printing substrate, the printing substrate is detached from the rotary table of the printer during measurement, and then the mounting disc is mounted on the rotary table of the printer. Preferably, the number of nozzles in the printer is 1 or more, if there is only one nozzle a, the nozzle is used, if there are a plurality of nozzles, such as the nozzle a7 and the nozzle b8, an appropriate nozzle is selected, and the nozzle cannot be replaced during the operation.

The above description is only of the preferred embodiments of the present invention, and it should be noted that: it will be apparent to those skilled in the art that various modifications and adaptations can be made without departing from the principles of the invention and these are intended to be within the scope of the invention.