阅读说明：本技术 一种回转件的3d打印路径及其增材制造方法 (3D printing path of rotating member and additive manufacturing method thereof ) 是由 吴玲珑 张召远 许春权 于 2020-12-24 设计创作，主要内容包括：本发明涉及一种回转件的3D打印路径,包括如下步骤：首先构建待制造零件的三维模型；其次对所述三维模型进行分层切片处理获取各层的切片轮廓,其中针对所述三维模型,以垂直于其回转轴的任意方向为法向,建立过回转轴的切平面,并所述切平面绕回转轴并每次旋转角度θ为间隔生成等距的切片轮廓；再计算获取所述切片轮廓的中轴线；而后计算中轴点处的切向量以及垂直于切向量的垂线,所述垂线与切片轮廓之间相交形成交点；最后生成Zigzag填充路径以及螺旋填充路径。本发明通过采用完整的Zigzag填充路径以及螺旋填充路径作为回转体的制造路径,无断点的制造路径极大提升了生产效率以及回转体精度以及表面光滑度。(The invention relates to a 3D printing path of a rotating member, which comprises the following steps: firstly, constructing a three-dimensional model of a part to be manufactured; secondly, carrying out layered slicing processing on the three-dimensional model to obtain slice profiles of all layers, wherein aiming at the three-dimensional model, a cutting plane passing through a rotating shaft is established by taking any direction perpendicular to the rotating shaft as a normal direction, and the cutting plane winds the rotating shaft and generates equidistant slice profiles at intervals by rotating an angle theta every time; then calculating and obtaining a central axis of the slice outline; then calculating a tangent vector at the central axis point and a vertical line perpendicular to the tangent vector, wherein the vertical line and the slice outline are intersected to form an intersection point; finally, a Zigzag filling path and a spiral filling path are generated. According to the invention, the complete Zigzag filling path and the spiral filling path are adopted as the manufacturing path of the revolving body, and the manufacturing path without break points greatly improves the production efficiency, the revolving body precision and the surface smoothness.)

1. A3D printing path of a rotating member, characterized in that: the method comprises the following steps:

s1: constructing a three-dimensional model of a part to be manufactured;

s2: carrying out layered slicing processing on the three-dimensional model to obtain slice outlines of all layers;

s2.1: aiming at the three-dimensional model, establishing a tangent plane passing through a rotating shaft by taking any direction vertical to the rotating shaft as a normal direction;

s2.2: the cutting plane winds the rotating shaft and generates equidistant slice profile sequences { P (0), P (theta), …, P (S theta), …, P ((n-1) theta), P (n theta) }by rotating the rotating shaft theta at intervals every time

Wherein S is an integer, and P (S theta) is a slice profile at the S theta angle;

s3: calculating and obtaining a central axis of the slice outline;

the central axis is a set of equidistant points from two or more points on different edges of the slice profile;

s4: resampling the central axis of the slice outline, and generating an equidistant central axis point sequence { P (S theta) along the length direction of the central axis and with equal arc length D as intervals₀,P(Sθ)₁,…,P(Sθ)_i,…,P(Sθ)_n-1,P(Sθ)_n}；

Wherein, P (S theta)_iIs the ith central axis point;

s5: calculating a tangent vector at the central axis point and a perpendicular line perpendicular to the tangent vector, wherein the perpendicular line and the slice outline are intersected to form an intersection point;

wherein the perpendicular line is connected withThe two intersecting end points between the slice profiles are respectively the lower end point P (S theta)_i ^{Lower part}And the upper endpoint P (S theta)_i ^{On the upper part}；

And S6, sequentially connecting upper end points corresponding to the middle axes at the same equal arc length D on different slicing profiles to form an inner profile, sequentially connecting lower end points corresponding to the middle axes at the same equal arc length D on different slicing profiles to form an outer profile, enclosing between the inner profile and the outer profile to form a printing area, and simultaneously connecting the middle axes in the printing area to form a new central axis.

S7 connection of lower terminal point P (S theta) in the same printing area_i ^{Lower part}And the upper end point P (S theta)_i ^{On the upper part}Form path one, connecting upper end point P (S theta)_i ^{On the upper part}And the upper end point P ((S +1) theta)_i ^{On the upper part}Form path two and connect the lower end point P ((S-1) theta)_i ^{Lower part}With lower endpoint P (S theta)_i ^{Lower part}And forming a path three, wherein the path one, the path two and the path three form a Zigzag filling path.

S8: and respectively carrying out interpolation on the path points in the adjacent layers or on the outer contours to calculate the spiral path points between the two layers. The interpolation method is as follows, wherein n is the total number of path points, k is the kth layer, and i is the ith path point:

2. a 3D printing path for a rotating member according to claim 1, wherein: the range of the rotation angle theta is theta_min≤θ≤θ_max，

Wherein the radius of gyration is r and the filling space is w, r_minIs the minimum radius of gyration, r, of the inner curved surface of the model_maxIs the maximum radius of gyration, w, of the outer curved surface of the model_minIs the minimum filling pitch, w_maxIs the maximum filling pitch.

3. A 3D printing path for a rotating member according to claim 1, wherein: the arc length D ranges from:

wherein h is_minAnd h_maxRespectively, a minimum print height and a maximum print height of a single layer.

4. A 3D printing path for a rotating member according to claim 1, wherein: and arc chamfers are arranged at the joints of the first path and the second path and the first path and the third path.

5. An additive manufacturing method based on the 3D printing path of the rotating member is characterized in that: the method comprises the following steps:

step 1: preparing a welding gun for additive manufacturing;

step 2: muzzle of mobile additive welding gun and P (0)₀ ^{Up or down}The corresponding intersection points are aligned, and the direction of the muzzle of the welding gun is controlled to be P (0)₀ ^{Up or down}The tangent vectors of the middle axis points corresponding to the intersection points are overlapped;

and step 3: and controlling the welding gun to move along the Zigzag filling path and the spiral filling path to perform material increase, wherein the direction of the muzzle of the welding gun is always coincided with the tangent vector of the filling path in the moving process of the welding gun.

6. An additive manufacturing method according to claim 5, wherein: velocity v of the first path₁Speed of path twoSpeed of path threeWherein l is the distance between adjacent middle axis points on the new middle axis corresponding to the path one, and l is the distance between the adjacent middle axis points on the new middle axis corresponding to the path one₂And l₃The lengths of the path two and the path three are respectively corresponding.

Technical Field

The invention relates to the technical field of 3D printing technology, in particular to a 3D printing path of a rotary member and an additive manufacturing method thereof.

Background

In the additive manufacturing technology, scan filling path planning is performed on slice outlines of a three-dimensional model after layered slicing, which is one of key technologies.

At present, the three-dimensional model mostly adopts sections which are on the horizontal plane and are equally spaced in the vertical direction as slices, the slices form a slice outline, and then a reciprocating linear method or an offset outline method is adopted to generate a scanning filling path; the scanning lines are filled in a Z shape along the direction of an included angle between the scanning lines and the coordinate axis, when a reciprocating linear method is adopted to generate a filling path for the section outline of the revolving body with a hollow center, a continuous printing path is difficult to form, and the surface appearance at the corners is poor.

Disclosure of Invention

In view of the defects in the prior art, an object of the present invention is to provide a 3D printing path for a rotary member, wherein a complete spiral path is used as a manufacturing path for a rotary body, and the manufacturing path without a break point greatly improves the production efficiency, the precision of the rotary body and the surface smoothness.

The above object of the present invention is achieved by the following technical solutions:

a 3D printing path of a rotating member, comprising the steps of:

s1: constructing a three-dimensional model of a part to be manufactured;

s2: carrying out layered slicing processing on the three-dimensional model to obtain slice outlines of all layers;

s2.1: aiming at the three-dimensional model, establishing a tangent plane passing through a rotating shaft by taking any direction vertical to the rotating shaft as a normal direction;

s2.2: the cutting plane winds the rotating shaft and generates equidistant slice profile sequences { P (0), P (theta), …, P (S theta), …, P ((n-1) theta), P (n theta) }by rotating the rotating shaft theta at intervals every time

Wherein S is an integer, and P (S theta) is a slice profile at the S theta angle;

s3: calculating and obtaining a central axis of the slice outline;

the central axis is a set of equidistant points from two or more points on different edges of the slice profile;

s4: resampling the central axis of the slice outline, and generating an equidistant central axis point sequence { P (S theta) along the length direction of the central axis and with equal arc length D as intervals₀,P(Sθ)₁,…,P(Sθ)_i,…,P(Sθ)_n-1,P(Sθ)_n}；

Wherein, P (S theta)_iIs the ith central axis point;

s5: calculating a tangent vector at the central axis point and a perpendicular line perpendicular to the tangent vector, wherein the perpendicular line and the slice outline are intersected to form an intersection point;

wherein the two intersecting end points between the perpendicular line and the slice outline are respectively a lower end point P (S theta)_i ^{Lower part}And the upper endpoint P (S theta)_i ^{On the upper part}；

And S6, sequentially connecting upper end points corresponding to the middle axes at the same equal arc length D on different slicing profiles to form an inner profile, sequentially connecting lower end points corresponding to the middle axes at the same equal arc length D on different slicing profiles to form an outer profile, enclosing between the inner profile and the outer profile to form a printing area, and simultaneously connecting the middle axes in the printing area to form a new central axis.

S7 connection of lower terminal point P (S theta) in the same printing area_i ^{Lower part}And the upper end point P (S theta)_i ^{On the upper part}Form path one, connecting upper end point P (S theta)_i ^{On the upper part}And the upper end point P ((S +1) theta)_i ^{On the upper part}Form path two and connect the lower end point P ((S-1) theta)_i ^{Lower part}With lower endpoint P (S theta)_i ^{Lower part}And forming a path three, wherein the path one, the path two and the path three form a Zigzag filling path.

S8: the path points on the inner or outer contour of the previous layer of printing area correspond to the path points on the inner or outer contour of the next layer of printing area one by one, and the path points in the adjacent layer or outer contour are interpolated to calculate the distance between the two layersA spiral path point. The interpolation method is as follows, wherein n is the total number of path points, k is the kth layer, and i is the ith path point:

the present invention in a preferred example may be further configured to: the range of the rotation angle theta is theta_min≤θ≤θ_max。

Wherein the radius of gyration r and the filling space w, r_minIs the minimum radius of gyration, r, of the inner curved surface of the model_maxIs the maximum radius of gyration, w, of the outer curved surface of the model_minIs the minimum filling pitch, w_maxIs the maximum filling pitch.

The present invention in a preferred example may be further configured to: the arc length D is in the range of

Wherein h is_minAnd h_maxRespectively, a minimum print height and a maximum print height of a single layer.

The present invention in a preferred example may be further configured to: and arc chamfers are arranged at the joints of the first path and the second path and the first path and the third path.

Another object of the present invention is to provide an additive manufacturing method, in which the direction of the muzzle of the welding gun is always coincident with the tangent vector of the filling path during the additive manufacturing process, so as to further improve the surface accuracy of the revolving body.

The above object of the present invention is achieved by the following technical solutions:

an additive manufacturing method of a 3D printing path based on the rotary member comprises the following steps:

step 1: preparing a welding gun for additive manufacturing;

step 2: muzzle of mobile additive welding gun and P (0)₀ ^{Up or down}The corresponding intersection points are aligned, and the direction of the muzzle of the welding gun is controlled to be P (0)₀ ^{Up or down}The tangent vectors of the middle axis points corresponding to the intersection points are overlapped;

and step 3: and controlling the welding gun to move along the Zigzag filling path and the spiral filling path to perform material increase, wherein the direction of the muzzle of the welding gun is always coincided with the tangent vector of the filling path in the moving process of the welding gun.

The present invention in a preferred example may be further configured to: the moving speed v of the welding gun of the path I₁Moving speed of welding gun on path twoMoving speed of welding gun in path threeWherein l is the distance between adjacent middle axis points on the new middle axis corresponding to the path one, and l is the distance between the adjacent middle axis points on the new middle axis corresponding to the path one₂And l₃The lengths of the path two and the path three are respectively corresponding.

In summary, the invention includes at least one of the following beneficial technical effects:

1. the complete spiral path is adopted as the manufacturing path of the revolving body, and the manufacturing path without break points greatly improves the production efficiency, the revolving body precision and the surface smoothness;

2. in the additive manufacturing process, the direction of a muzzle of a welding gun is always superposed with a tangent vector at the central axis point, so that the surface precision of the revolving body is further improved;

3. in the process of additive manufacturing, different welding gun moving speeds are used for different path sections, so that a printing area can be smoother, and the phenomenon that the path sections of inner contours are too high in accumulation is avoided.

Drawings

FIG. 1 is a display slice profile for use on a solid of revolution;

FIG. 2 is a schematic diagram showing the pivot point on the slice outline;

FIG. 3 is a schematic diagram showing the upper end point and the lower end point corresponding to the middle axis point;

FIG. 4 is a view for showing a printing area;

FIG. 5 is a Zigzag fill path for a print zone;

fig. 6 is a schematic diagram showing a spiral filling path.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

The first embodiment is as follows:

a 3D printing path of a rotating member, comprising the steps of: for the sake of understanding, the results of the steps are shown by taking a solid of revolution as an example,

s1: constructing a three-dimensional model of a part to be manufactured;

as shown in fig. 1, S2: carrying out layered slicing processing on the three-dimensional model to obtain slice outlines of all layers;

s2.1: aiming at the three-dimensional model, establishing a tangent plane passing through a rotating shaft by taking any direction vertical to the rotating shaft as a normal direction;

s2.2: the slicing planes wind around the rotating shaft and generate equidistant slicing profile sequences { P (0), P (theta), …, P (S theta), …, P ((n-1) theta), P (n theta) }at intervals of theta rotation angle of each time

Wherein S is an integer, and P (S theta) is a slice profile at the S theta angle; the range of the rotation angle theta is theta_min≤θ≤θ_max，

Wherein the radius of gyration is r and the filling space is w, r_minIs the minimum radius of gyration, r, of the inner curved surface of the model_maxIs the maximum radius of gyration, w, of the outer curved surface of the model_minIs the minimum filling pitch, w_maxIs the maximum filling pitch;

as shown in fig. 2, S3: calculating a central axis of the slice outline;

wherein the central axis is a set of equidistant points from two or more points on different edges of the slice profile;

s4: resampling the central axis of the slice profile, and generating an equidistant central axis point sequence { P (S theta) along the length direction of the central axis and with equal arc length D as an interval₀,P(Sθ)₁,…,P(Sθ)_i,…,P(Sθ)_n-1,P(Sθ)_n}；

Wherein, P (S theta)_iIs the ith central axis point; the arc length D ranges from:

wherein h is_minAnd h_maxA minimum print height and a maximum print height of a single layer, respectively;

as shown in fig. 3, S5: calculating tangent vectors at the central axis point and vertical lines perpendicular to the tangent vectors, wherein the vertical lines and the slice outlines are intersected to form intersection points;

wherein the two intersecting end points between the perpendicular line and the slice outline are respectively a lower end point P (S theta)_i ^{Lower part}And the upper endpoint P (S theta)_i ^{On the upper part}；

As shown in fig. 4, S6, connecting the upper end points corresponding to the middle axis at the same equal arc length D on different slice profiles in sequence to form an inner profile, connecting the lower end points corresponding to the middle axis at the same equal arc length D on different slice profiles in sequence to form an outer profile, enclosing between the inner profile and the outer profile to form a printing area, and connecting the middle axis points in the printing area to form a new central axis;

as shown in FIG. 5, S7, the lower end point P (S θ) is connected in the same printing area_i ^{Lower part}And the upper end point P (S theta)_i ^{On the upper part}Form path one, connecting upper end point P (S theta)_i ^{On the upper part}And upper end point P((S+1)θ)_i ^{On the upper part}Form path two and connect the lower end point P ((S-1) theta)_i ^{Lower part}With lower endpoint P (S theta)_i ^{Lower part}Forming a third path, wherein the first path, the second path and the third path form a Zigzag filling path;

as shown in fig. 6, S8: and respectively carrying out interpolation on the path points in the adjacent layers or on the outer contours to calculate the spiral path points between the two layers. The interpolation method is as follows, wherein n is the total number of path points, k is the kth layer, and i is the ith path point:

example two:

an additive manufacturing method based on a 3D printing path of a rotating member in the first embodiment includes the following steps:

step 1: preparing a welding gun for additive manufacturing, wherein the muzzle diameter of the welding gun is d;

step 2: muzzle of mobile additive welding gun and P (0)₀ ^{Up or down}The corresponding intersection points are aligned, and the direction of the muzzle of the welding gun is controlled to be P (0)₀ ^{Up or down}The tangent vectors of the middle axis points corresponding to the intersection points are overlapped;

and step 3: and controlling the welding gun to move along the Zigzag filling path and the spiral filling path to perform material increase, wherein the direction of the muzzle of the welding gun is always coincided with the tangent vector of the filling path in the moving process of the welding gun.

Wherein the moving speed range of the welding gun is the moving speed v at one position of the path₁Moving speed of the second place of the pathMoving speed of three positions on pathWherein l is the distance between adjacent medial axis points on the new medial axis corresponding to path one, l is the distance between adjacent medial axis points on the new medial axis corresponding to path one₂And l₃The lengths of the path two and the path three are respectively corresponding.

The embodiments of the present invention are preferred embodiments of the present invention, and the scope of the present invention is not limited by these embodiments, so: all equivalent changes made according to the structure, shape and principle of the invention are covered by the protection scope of the invention.