Block support volume reduction design method

Abstract

The invention discloses a blocky support volume reduction design method which comprises the following steps: S1, defining a product model as a step model, and importing the step model into preset process software; s2, performing triangular patch repair on the step model; s3, a blocky support is designed for the suspended part of the repaired step model, the blocky support comprises an upper supporting part and a lower supporting part, the upper supporting part is located at the upper end of the lower supporting part, an upper inclined body is arranged at the junction of the lower supporting part and the upper supporting part, the upper inclined body extends obliquely upwards, and the lower inclined body is located at the lower end of the lower supporting part; the upper inclined body is attached to the bottom of one side, extending out of the outer side of the lower supporting part, of the upper supporting part, a lower inclined body is arranged at the bottom of the lower supporting part, and the lower inclined body is attached to one part of the bottom of the lower supporting part. According to the method, editable parameters of the support can be effectively increased, meanwhile, the size of the support can be greatly reduced, and the product forming efficiency can be improved.

Description

Technical Field

[0001] The present invention relates to the field of metal additive manufacturing, and in particular to a block support volume reduction design method. Background Art

[0002] At present, the laser selective melting forming technology adopts the technical principle of stacking layers. If the angle between certain features of the part and the horizontal direction is less than 45°, support needs to be added. For related design methods, please refer to the Chinese patent publication number CN116714253A, entitled "A method for optimizing the direction of three-dimensional printing based on thermal deformation". However, in conventional block supports, there are few editable parameters, resulting in a large support volume and a long forming time, which seriously affects the forming efficiency. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a block support volume reduction design method that can increase editable parameters of support and significantly reduce support volume, thereby helping to improve forming efficiency, in response to the deficiencies of the prior art.

[0004] In order to solve the above technical problems, the present invention adopts the following technical solutions.

[0005] A method for designing a block support to reduce volume comprises the following steps: step S1, defining a product model as a step model, and importing the step model into a preset process software; step S2, performing triangular patch repair on the step model; step S3, designing a block support for the suspended part of the step model after the repair, the block support comprising an upper support portion and a lower support portion, the upper support portion being located at the upper end of the lower support portion, an upper bevel being provided at the junction of the lower support portion and the upper support portion, the upper bevel extending obliquely upward, the upper bevel being fitted with the bottom of a side portion of the upper support portion extending out of the outer side of the lower support portion, the bottom of the lower support portion being provided with a lower bevel, the lower bevel being fitted with a portion of the bottom of the lower support portion.

[0006] Preferably, in step S3, the upper italic body is provided on both the left and right sides of the lower supporting portion.

[0007] Preferably, step S3 includes: step S30, defining the angle between the upper italic and the horizontal direction as α, and the thickness dimension as T1, defining the angle between the lower italic and the horizontal direction as β, and the thickness dimension as T2, then there are parameter constraints: 90°>α>30°; 90°>β>30°; 20mm≥T1≥0.3mm; 20mm≥T2≥0.3mm.

[0008] Preferably, in step S3, the lower italic is a triangle, an oblong, an arch, an M-shaped or a Y-shaped italic.

[0009] Preferably, the upper support portion includes a plurality of upper support units distributed in an array, and the step S3 includes: step S31, defining the side length of the upper support unit as L1 and the width as W1, defining the upper support unit spacing in the X direction as l1 and the Y direction as w1, defining the upper support unit middle filling line spacing in the X direction as l2 and the Y direction spacing as w2, defining the side line length of the upper support unit as L1 and the width as W1, and defining the multiples as N1 and N2, then there are parameter constraints: L1=N1*l2; W1=N2*w2; 1.5*l2≥l1≥0.7*l2; 1.5*w2≥w1≥0.7*w2; 15≥N1≥1; 15≥N2≥1.

[0010] Preferably, the lower support portion includes a plurality of lower support units distributed in an array, and the step S3 includes: step S32, defining the side length of the lower support unit as L2 and the width as W2, defining the X-direction spacing of the lower support unit as l3 and the Y-direction spacing as w3, defining the X-direction spacing of the middle filling lines of the lower support unit as l4 and the Y-direction spacing as w4, defining multiples N3 and N4, then there are parameter constraints: L2=N3*l4; W2=N2*w4; 1.5*l4≥l3≥0.7*l4; 1.5*w4≥w3≥0.7*w4; 20≥N3≥1; 20≥N4≥1; 5*l2≥l4≥1.05*l2; 5*w2≥w4≥1.05*w2; l3>l1; w2>w4.

[0011] Preferably, the step S3 comprises: step S33, designing an elliptical hollow hole and a circular hollow hole for the upper supporting unit and the lower supporting unit.

[0012] Preferably, step S3 includes: step S34, defining the major axis size of the elliptical hollow hole as D, the minor axis size as d, the spacing between adjacent elliptical hollow holes as H, the spacing between the elliptical hollow hole and the support edge line as t, defining the diameter of the circular hollow hole as φ, the horizontal spacing of the circular hollow holes as d1, the distance between the circular hollow holes and the support side edge line is d2, and the distance between the circular hollow holes and the support top edge line is d3, then there are parameter constraints; 10mm≥D≥1mm; 8mm≥d≥0.5mm; 10mm≥H≥0.5mm; 10mm≥t≥0.5mm; 6mm≥φ≥0.5mm; 6mm≥d1≥0.3mm; 6mm≥d2≥0.3mm; 10mm≥d3>0mm.

[0013] Preferably, in step S3, the filling line shapes of the upper supporting unit and the lower supporting unit may be crisscrossed longitude and latitude lines, spiral lines, U-shaped lines, snakes, grids, circles or chessboards.

[0014] Preferably, the filling lines of the upper support unit and the lower support unit have filling line hollow holes, and the step S3 includes: step S35, defining the size φ1 of the filling line hollow holes, the spacing between adjacent filling line hollow holes is D1, the size of the filling line hollow holes from the top of the support filling line is D2, the horizontal spacing of the filling line hollow holes is D3, and the size of the filling line hollow holes from the edge of the support filling line is D4, then there are parameter constraints: 6mm≥φ1≥0.5mm; 10mm≥D1≥0.5mm; 8mm≥D2≥0.5mm; 6mm≥D3≥0.5mm; 10mm≥D4≥0.5mm.

[0015] In the block support volume reduction design method disclosed in the present invention, a step-type feature that needs to add support is taken as an example to illustrate, and the product is defined as a step. Specifically, the part that needs to add support is the bottom horizontal structure that grows in mid-air. At the beginning of the design, the step model is imported into the process software for adding support. Because the step is only a partial feature of the part, when the process software is placed, it is placed by attaching the substrate in its plane position. At this time, the step part is suspended, and then the triangular facets of the step are repaired to eliminate broken, reversed, and missing triangular facets. After the step repair is completed, a support including the above-mentioned upper support part, lower support part, upper italic body and lower italic body is generated for its suspended part. Compared with the prior art, the present invention can effectively increase the editable parameters of the support, and at the same time can greatly reduce the support volume, which helps to improve the product forming efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A stereogram of a block support;

[0017] Figure 2 It is the front view of the block support;

[0018] Figure 3 is a top view of the upper support portion;

[0019] Figure 4 for Figure 3 A magnified view of part A;

[0020] Figure 5 is a bottom view of the lower support portion;

[0021] Figure 6 for Figure 5 A magnified view of part B;

[0022] Figure 7 It is the front view of the edge line of the upper and lower support units;

[0023] Figure 8 It is a three-dimensional diagram of the edges of the upper and lower support units;

[0024] Fig. 9This is the front view of the upper and lower support units after adding fill lines;

[0025] Fig.10 The three-dimensional image after adding fill lines to the upper and lower support units;

[0026] Fig.11 A three-dimensional image of the fill line;

[0027] Fig.12 This is the front view of the fill line. DETAILED DESCRIPTION

[0028] The present invention is described in more detail below with reference to the accompanying drawings and embodiments.

[0029] The present invention discloses a block support volume reduction design method, combining Figure 1 to Figure 2 As shown, it includes the following steps:

[0030] Step S1, defining the product model as a step model, and importing the step model into a preset process software;

[0031] Step S2, performing triangular patch repair on the step model;

[0032] Step S3, designing a block support for the suspended part of the step model after the repair is completed, the block support includes an upper support part 1 and a lower support part 2, the upper support part 1 is located at the upper end of the lower support part 2, an upper bevel 3 is provided at the junction of the lower support part 2 and the upper support part 1, the upper bevel 3 extends obliquely upward, the upper bevel 3 is in contact with the bottom of a side portion of the upper support part 1 extending out of the outer side of the lower support part 2, the bottom of the lower support part 2 is provided with a lower bevel 4, and the lower bevel 4 is in contact with a portion of the bottom of the lower support part 2.

[0033] In the above method, a step-type feature that needs to add support is taken as an example to illustrate, and the product is defined as a step. Specifically, the part that needs to add support is the bottom horizontal structure that grows in the air. At the beginning of the design, the step model (.st l format file) is imported into the process software for adding support. Because the step is only a partial feature of the part, when the process software is placed, it is placed with its plane position attached to the substrate. At this time, the step part is suspended. Subsequently, the triangular facets of the step (.st l format file is a series of triangular facets connected and enveloped to form a three-dimensional model of the product) are repaired to eliminate broken, reversed, and missing triangular facets. After the step repair is completed, the support including the above-mentioned upper support part 1, lower support part 2, upper italic body 3 and lower italic body 4 is generated for its suspended part. Compared with the prior art, the present invention can effectively increase the editable parameters of the support, and at the same time can greatly reduce the support volume, which is helpful to improve the product forming efficiency.

[0034] In this embodiment, in the step S3 , the upper inclined body 3 is provided on both the left and right sides of the lower supporting portion 2 .

[0035] See also Figure 1 and Figure 2 In this embodiment, the block support is composed of the following parts: an upper support, a lower support, an upper italic, and a lower italic, wherein the upper support and the lower support are both composed of a series of support units, and the support unit is composed of a support edge line and a filling line. The upper support and the lower support are divided into two upper and lower parts at the horizontal connecting line of the support italic, the support unit of the upper support edge is connected to the upper italic, and the core of the lower support is connected to the lower italic.

[0036] Among them: the main function of the upper italic body is to prevent the upper support edge from falling directly on the substrate, thereby reducing the support height and thus reducing the support volume; the main function of the lower italic body is to prevent the lower support core from falling directly on the substrate, thereby reducing the support height and thus reducing the support volume;

[0037] Hollow structures of different structural shapes are opened on the edge lines of the upper and lower support units, which can be elliptical, triangular, polygonal, circular, diamond, bridge arch and other shapes. The support volume can be further reduced by hollowing out.

[0038] Regarding the parameter constraints of the upper italic 3, in this embodiment, see Figure 2 , the step S3 comprises:

[0039] Step S30, define the angle between the upper italic body 3 and the horizontal direction as α, the thickness dimension as T1, define the angle between the lower italic body 4 and the horizontal direction as β, the thickness dimension as T2, then there are parameter constraints:

[0040] 90°>α>30°;

[0041] 90°>β>30°;

[0042] 20mm≥T1≥0.3mm;

[0043] 20mm≥T2≥0.3mm.

[0044] In this embodiment, the lower support height is defined as H1, and the value of H1 is less than the height of the horizontal step of the ladder. The thickness of the upper and lower italics can be the same or different. Its purpose is to constrain the support connected to it so that it is not hollowed out within a specific size range and the bottom is closed to form a solid body, so as to enhance the support strength and achieve a better shape control effect.

[0045] As a preferred embodiment, in step S3, the lower italic body 4 is a triangle, an oblong, an arch, an M-shaped or a Y-shaped italic body. In practical applications, by adjusting the above parameters, the support form can be reasonably set and the support volume can be reduced, thereby improving the forming efficiency.

[0046] In this embodiment, the upper support unit and the lower support unit may be the same size or different in size. In principle, the length and width of the upper and lower support units should not be less than the size of the upper support unit. Figure 3-Figure 6 shown.

[0047] Specifically, the upper support portion 1 includes a plurality of upper support units 10 distributed in an array, and the step S3 includes:

[0048] Step S31, define the side length of the upper support unit 10 as L1, the width as W1, define the upper support unit 10 X-direction spacing as l1, the Y-direction spacing as w1, define the upper support unit 10 middle filling line X-direction spacing as l2, the Y-direction spacing as w2, define the sideline length of the upper support unit 10 as L1, the width as W1, define the multiples as N1, N2, then there are parameter constraints:

[0049] L1=N1*l2;

[0050] W1=N2*w2;

[0051] 1.5*l2≥l1≥0.7*l2;

[0052] 1.5*w2≥w1≥0.7*w2;

[0053] 15≥N1≥1;

[0054] 15≥N2≥1.

[0055] The length L1 and width W1 of the upper support unit can be different or the same, but the difference between them cannot be greater than two-thirds of the value in any direction. At the same time, the multiples N1 and N2 can be the same or different.

[0056] Similarly, the lower support portion 2 includes a plurality of lower support units 20 distributed in an array, and the step S3 includes:

[0057] Step S32, define the side length of the lower support unit 20 as L2, the width as W2, define the X-direction spacing of the lower support unit 20 as l3, the Y-direction spacing as w3, define the X-direction spacing of the middle filling line of the lower support unit 20 as l4, the Y-direction spacing as w4, define the multiples N3 and N4, then there are parameter constraints:

[0058] L2=N3*l4;

[0059] W2=N2*w4;

[0060] 1.5*l4≥l3≥0.7*l4;

[0061] 1.5*w4≥w3≥0.7*w4;

[0062] 20≥N3≥1;

[0063] 20≥N4≥1;

[0064] 5*l2≥l4≥1.05*l2;

[0065] 5*w2≥w4≥1.05*w2;

[0066] l3>l1;

[0067] w2>w4.

[0068] Through the above formula, the spacing between the edge lines and filling lines of the upper and lower support units can be constrained, so that the width of the lower support is larger and the spacing of the upper support is smaller. The large width is conducive to reducing the support volume and improving the forming efficiency. It is also convenient for powder discharge and support removal. In addition, the small spacing of the upper support increases the support density, increases the contact area between the support and the part, and improves the strength of the support, which has a better shape control effect.

[0069] On this basis, the support unit is composed of support edges and filling lines, such as Figures 7 to 10 As shown, the edge line of the support unit body is hollowed out by a series of long elliptical holes, and smaller horizontally arranged hollow holes are arranged above the support edge line. The hole type can be circular, elliptical, triangular, trapezoidal, serrated, polygonal, rhombus, tree branch, etc. For ease of explanation, this embodiment takes circular hollow holes as an example. The purpose of the hollow holes is to form a weak bond at the contact point between the support edge line and the supported part, improve the ease of subsequent support removal, reduce support residues, and thereby improve the grinding efficiency. Moreover, the hollow holes can be distributed along the support edge line in one layer or in multiple layers, and the specific shape can be set as needed.

[0070] In practical applications, the interior of the support unit body surrounded by the support edge line is filled with filling lines. The function of the filling lines is to reduce and increase the contact area between the support and the supported part, increase the support strength, and achieve a better shape control effect. It can be seen that in this embodiment, the step S3 includes:

[0071] Step S33 , designing an elliptical hollow hole 11 and a circular hollow hole 12 for the upper support unit 10 and the lower support unit 20 .

[0072] Furthermore, the step S3 comprises:

[0073] Step S34, define the major axis size of the elliptical hollow hole 11 as D, the minor axis size as d, the spacing between adjacent elliptical hollow holes 11 as H, the spacing between the elliptical hollow hole 11 and the support edge line as t, define the diameter of the circular hollow hole 12 as φ, the horizontal spacing of the circular hollow holes 12 as d1, the distance between the circular hollow hole 12 and the support side edge line is d2, and the distance between the circular hollow hole 12 and the support top edge line is d3, then there are parameter constraints;

[0074] 10mm≥D≥1mm;

[0075] 8mm≥d≥0.5mm;

[0076] 10mm≥H≥0.5mm;

[0077] 10mm≥t≥0.5mm;

[0078] 6mm≥φ≥0.5mm;

[0079] 6mm≥d1≥0.3mm;

[0080] 6mm≥d2≥0.3mm;

[0081] 10mm≥d3>0mm.

[0082] Among them, by defining the characteristic parameters of the edge of the support unit and quantifying the data, the support parameters can be reasonably adjusted according to the characteristic morphology of the supported product, thereby reducing the support volume and improving the forming efficiency.

[0083] Combination Fig.11 and Fig.12 As shown, in the step S3, the filling line shape of the upper support unit 10 and the lower support unit 20 can be a criss-cross longitude and latitude line shape, a spiral line shape, a U-shaped shape, a snake shape, a grid shape, a circle or a chessboard shape.

[0084] Specifically in this embodiment, the filling line of the support unit body can be in the form of criss-cross longitude and latitude, spiral, U-shaped, serpentine, grid, circle, chessboard, gossip, etc. For ease of explanation, this embodiment is described by taking the grid shape as an example. Specifically, the support unit filling line is composed of filling lines, hollow holes, and supporting teeth that alternate vertically and horizontally. The hollow hole type can be circular, elliptical, triangular, trapezoidal, zigzag, polygonal, rhombus, tree branch, etc. For ease of explanation, the present invention is described by taking a circular hollow hole as an example. The purpose of the hollow hole is to form a weak bond between the support filling line and the supported part at the contact point. Improve the ease of subsequent support removal, reduce support residues, and thereby improve grinding efficiency. The hollow holes can be distributed in one layer or multiple layers along the support filling line. The specific form can be set as needed.

[0085] In this embodiment, the filling lines of the upper support unit 10 and the lower support unit 20 have filling line hollow holes 21, and the step S3 includes:

[0086] Step S35, define the size φ1 of the filling line hollow hole 21, the spacing between adjacent filling line hollow holes 21 is D1, the distance between the filling line hollow hole 21 and the top of the supporting filling line is D2, the horizontal spacing between the filling line hollow holes 21 is D3, and the distance between the filling line hollow hole 21 and the edge of the supporting filling line is D4, then there are parameter constraints:

[0087] 6mm≥φ1≥0.5mm;

[0088] 10mm≥D1≥0.5mm;

[0089] 8mm≥D2≥0.5mm;

[0090] 6mm≥D3≥0.5mm;

[0091] 10mm≥D4≥0.5mm.

[0092] Among them, by defining the characteristic parameters of the support unit filling line and quantifying the data, the support parameters can be reasonably adjusted according to the characteristic morphology of the supported product, thereby reducing the support volume and improving the forming efficiency.

[0093] In this embodiment, the support edge line and the support filling line are scanned line segments, not entities with thickness. During laser selective melting, the support edge line can be scanned once or twice, while the filling line is scanned only once. If the support edge line is scanned twice, the first scan is performed along the actual contour line. During the second scan, the laser scanning line is offset inward along the actual contour line by 0.01 to 0.2 mm. Through two scans, the strength of the support edge line can be increased, thereby improving the support strength, which can achieve better shape control effects for high-stress materials such as titanium alloy series and high-temperature alloy series materials.

[0094] For the upper italic and lower italic, the laser can scan once or twice as needed. For high stress materials such as titanium alloy series and high temperature alloy series materials, it can be scanned twice to achieve better shape control effect.

[0095] The present invention effectively increases the editable support parameters through the above-mentioned design method, and helps to reasonably select effective and feasible support parameters according to the different characteristics of different products, thereby greatly reducing the support volume and improving the forming efficiency.

[0096] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions or improvements made within the technical scope of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for designing a block support to reduce volume, characterized in that: The steps include: Step S1, defining the product model as a step model, and importing the step model into a preset process software; Step S2, performing triangular patch repair on the step model; Step S3, designing a block support for the suspended part of the step model after the repair is completed, the block support comprising an upper support part (1) and a lower support part (2), the upper support part (1) is located at the upper end of the lower support part (2), an upper bevel (3) is provided at the junction of the lower support part (2) and the upper support part (1), the upper bevel (3) extends obliquely upward, the upper bevel (3) is in contact with the bottom of a side portion of the upper support part (1) extending out of the outer side of the lower support part (2), the bottom of the lower support part (2) is provided with a lower bevel (4), and the lower bevel (4) is in contact with a part of the bottom of the lower support part (2).

2. The block support volume reduction design method according to claim 1, characterized in that: In the step S3, the upper oblique body (3) is provided on both the left and right sides of the lower support portion (2).

3. The block support volume reduction design method according to claim 1, characterized in that: The step S3 comprises: Step S30, define the angle between the upper italic body (3) and the horizontal direction as α, and the thickness dimension as T1, define the angle between the lower italic body (4) and the horizontal direction as β, and the thickness dimension as T2, then there are parameter constraints: 90°＞α＞30°； 90°＞β＞30°； 20mm≥T1≥0.3mm; 20mm≥T2≥0.3mm.

4. The block support volume reduction design method according to claim 1, characterized in that: In the step S3, the lower italic (4) is a triangular, oblong, arched, M-shaped or Y-shaped italic.

5. The block support volume reduction design method according to claim 1, characterized in that: The upper support portion (1) comprises a plurality of upper support units (10) distributed in an array, and step S3 comprises: Step S31, define the side length of the upper support unit (10) as L1, the width as W1, define the spacing of the upper support unit (10) in the X direction as l1, and the spacing in the Y direction as w1, define the spacing of the middle filling lines of the upper support unit (10) in the X direction as l2, and the spacing in the Y direction as w2, define the side line length of the upper support unit (10) as L1, the width as W1, define the multiples as N1 and N2, then there are parameter constraints: L1=N1*l2; W1=N2*w2; 1.5*l2≥l1≥0.7*l2； 1.5*w2≥w1≥0.7*w2; 15≥N1≥1； 15≥N2≥1。 6. The method for designing a block support to reduce volume as claimed in claim 1, characterized in that: The lower support portion (2) comprises a plurality of lower support units (20) distributed in an array, and step S3 comprises: Step S32, define the side length of the lower support unit (20) as L2, the width as W2, define the X-direction spacing of the lower support unit (20) as l3, the Y-direction spacing as w3, define the X-direction spacing of the middle filling line of the lower support unit (20) as l4, the Y-direction spacing as w4, define the multiples N3 and N4, then there are parameter constraints: L2=N3*l4; W2=N2*w4; 1.5*l4≥l3≥0.7*l4； 1.5*w4≥w3≥0.7*w4; 20≥N3≥1； 20≥N4≥1； 5*l2≥l4≥1.05*l2； 5*w2≥w4≥1.05*w2; l3＞l1； w2>w4.

7. The block support volume reduction design method according to claim 1, characterized in that: The step S3 comprises: Step S33, designing an elliptical hollow hole (11) and a circular hollow hole (12) for the upper support unit (10) and the lower support unit (20).

8. The method for designing a block support to reduce volume as claimed in claim 7, characterized in that: The step S3 comprises: Step S34, define the major axis size of the elliptical hollow hole (11) as D, the minor axis size as d, the spacing between adjacent elliptical hollow holes (11) as H, the spacing between the elliptical hollow hole (11) and the supporting edge line as t, and define the diameter of the circular hollow hole (12) as The horizontal spacing of the circular hollow holes (12) is d1, the distance between the circular hollow holes (12) and the side edge of the support is d2, and the distance between the circular hollow holes (12) and the top edge of the support is d3, so there are parameter constraints; 10mm≥D≥1mm; 8mm≥d≥0.5mm; 10mm≥H≥0.5mm; 10mm≥t≥0.5mm; 6mm≥d1≥0.3mm; 6mm≥d2≥0.3mm; 10mm≥d3>0mm.

9. The method for designing a block support to reduce volume as claimed in claim 1, characterized in that: In the step S3, the filling line shape of the upper support unit (10) and the lower support unit (20) can be a criss-cross longitude and latitude line shape, a spiral line shape, a U-shaped shape, a snake shape, a grid shape, a circle or a chessboard shape.

10. The method for designing a block support to reduce volume as claimed in claim 9, characterized in that: The filling lines of the upper support unit (10) and the lower support unit (20) have filling line hollow holes (21), and the step S3 comprises: Step S35, defining the size of the fill line hollow hole (21) The spacing between adjacent filling line hollow holes (21) is D1, the distance between the filling line hollow holes (21) and the top of the supporting filling line is D2, the horizontal spacing between the filling line hollow holes (21) is D3, and the distance between the filling line hollow holes (21) and the edge of the supporting filling line is D4, then there are parameter constraints: 10mm≥D1≥0.5mm; 8mm≥D2≥0.5mm; 6mm≥D3≥0.5mm; 10mm≥D4≥0.5mm.

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