Metal 3D shoe mold printing method

Abstract

The invention relates to a metal 3D (three-dimensional) shoe mold printing method, which belongs to the technical field of 3D printing and comprises the following steps: S1, a laser galvanometer group is arranged and comprises a small light spot galvanometer unit arranged in the middle and a plurality of large light spot galvanometer units arranged around the small light spot galvanometer unit; the printing range of the small light spot galvanometer unit covers the whole part, and the set of the printing ranges of the large light spot galvanometer units covers the whole part; and S2, the printing data of the outer surface of the part is distributed to the small light spot galvanometer units, the printing data of the inner part of the part is distributed to the large light spot galvanometer units, and 3D printing is conducted on the part. According to the method, the splicing parts are all located inside the shoe mold, the outer surface is printed through a galvanometer unit, no splicing exists on the surface, the requirements of high surface quality, low surface roughness and low internal density of a shoe mold finished product are met, the printing data distribution amount can be optimized, the printing speed is optimal, and the printing efficiency is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of 3D printing, and in particular relates to a metal 3D shoe mold printing method. Background Art

[0002] Laser processing, such as laser cutting, laser welding, laser marking and laser 3D printing, usually uses a galvanometer to reflect a single laser beam and perform curved image scanning on a two-dimensional working plane or curved surface. Laser processing is an advanced rapid processing and manufacturing technology.

[0003] In 3D printing, SLA, SLS, and SLM use a galvanometer to reflect a single laser beam and perform image scanning and printing on a two-dimensional work plane. Compared with traditional subtractive manufacturing technology, 3D printing technology is an advanced additive manufacturing technology for rapid manufacturing of parts, and the function of SLM metal 3D printers is to use metal powder to melt under the heat of the laser beam, cool and condense, and then stack layers to manufacture parts.

[0004] Metal 3D printing has relatively high requirements for printing lasers. The laser beam needs to be pure single-mode output and the beam quality M2 needs to be less than 1.1. Lasers with high beam quality usually have low laser power and cannot be further used to improve printing efficiency. Therefore, in order to improve printing efficiency, the industry conventionally uses multiple laser beams to perform simultaneous scanning and printing through multiple galvanometer reflections to improve efficiency.

[0005] In metal 3D printing, a part print usually includes fill lines and contour lines. Fill lines are used to fill the internal area of ​​the sintered printed part, and contour lines are used to print the surface of the part. Contour lines and fill lines have different printing requirements: Contour lines require the smallest possible spot and accurate printing, so that the surface quality of the part is good enough and the roughness is low; fill lines require high printing efficiency and can scan and complete the filling content as quickly as possible; at the same time, in a printed pattern, the number of fill lines is much greater than the number of scan lines.

[0006] Therefore, in order to improve printing efficiency without reducing accuracy, a variable spot system can be used. A small spot is used for precise printing when printing contour lines, and a large spot is used when printing fill lines. This increases the laser power, increases the fill line spacing, and reduces the number of fill lines, thereby improving printing efficiency.

[0007] Metal 3D printed shoe molds are a very important application field in the current market. When printing shoe molds, the following requirements need to be met: 1. The surface quality requirements of the finished shoe mold parts are very high, the surface roughness requirements of the printed parts are very low, and the various subtle textures on the surface are required to be completely restored; 2. Since the interior of the shoe mold parts does not need to withstand various external tensile forces and pressures in subsequent production, the finished parts do not have high requirements for internal pores, density, etc.; 3. As a fast-moving consumer product, shoe molds have high requirements for the timeliness of printing processing, and the printing time needs to be shortened as much as possible when printing. In the current shoe mold printing field, in order to meet the surface quality requirements of printed shoe mold parts as much as possible, smaller laser spots are used for 3D sintering printing. Therefore, its printing efficiency is very low, and it is difficult to meet the market's time requirements for the shoe mold printing cycle. When a larger spot is used, improving efficiency faces the problem of reduced surface quality of shoe mold parts.

[0008] In order to improve printing efficiency, you can also use multiple lasers to print a shoe mold together to shorten the printing time. This method will cause the quality of the multiple laser joints to decrease. Since the shoe mold has high requirements for surface quality, the requirements for the seams at the multiple laser joints are higher. In most cases, the seams of laser joints will have a visible impact on the finished product, which also limits the method of using multiple lasers to print a shoe mold together to shorten the printing time. Summary of the invention

[0009] The purpose of the present invention is to provide a metal 3D shoe mold printing method to solve the problems of reduced quality of multi-laser splicing parts and low printing efficiency in existing multi-laser metal 3D shoe mold printing.

[0010] In order to achieve the above object, the technical solution of the present invention is as follows:

[0011] The present invention relates to a metal 3D shoe mold printing method, which comprises the following steps:

[0012] S1. Setting a laser galvanometer group, the laser galvanometer group includes a small spot galvanometer unit arranged in the center and a plurality of large spot galvanometer units arranged around the small spot galvanometer unit; the printing range of the small spot galvanometer unit covers the entire part, and the printing range of the large spot galvanometer unit covers the entire part;

[0013] S2. Assign the printing data of the external surface of the part to the small spot galvanometer unit, and assign the printing data of the internal part of the part to the large spot galvanometer units, and perform 3D printing on the part.

[0014] Preferably, in S2, the printing data of the internal part of the part is distributed to each large spot galvanometer unit according to the principle of the same data amount.

[0015] Preferably, in said S2, when the printing data of the inner part of the part is distributed to each large spot galvanometer unit, a remelting area of ​​adjacent large spot galvanometer units is set, and the width of the remelting area is not less than the printing drift of the large spot galvanometer unit.

[0016] Preferably, S2 allocates the printing data of the external surface of the part to the small spot galvanometer unit, allocates the printing data of the internal part of the part to the large spot galvanometer units, records the printing time of each large spot galvanometer unit as S1, and records the printing time of the small spot galvanometer unit as S2, and optimizes the distribution amount of the printing data according to the printing time of the large spot galvanometer unit and the small spot galvanometer unit, and the optimization method is:

[0017] When the printing time of the small spot galvanometer unit is not less than the printing time of the large spot galvanometer unit, the distribution amount of the printing data is not optimized;

[0018] When the printing time of the small spot galvanometer unit is less than the printing time of the large spot galvanometer unit, the printing data of part of the internal part is allocated to the small spot galvanometer unit, so that the printing time of the large spot galvanometer unit and the printing time of the small spot galvanometer unit after data allocation satisfy the following formula:

[0019]

[0020]

[0021] Among them, S1′ and S2′ are the printing times of the small-spot galvanometer unit and the large-spot galvanometer unit after optimization, respectively; S1 and S2 are the printing times of the small-spot galvanometer unit and the large-spot galvanometer unit before optimization, respectively; N is the total number of the small-spot galvanometer unit and the large-spot galvanometer unit; and M indicates that the printing efficiency of the large-spot galvanometer unit is M times that of the small-spot galvanometer unit.

[0022] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects:

[0023] 1. The laser galvanometer group used in the metal 3D shoe mold printing method involved in the present invention includes a small spot galvanometer unit arranged in the center and a plurality of large spot galvanometer units arranged around the small spot galvanometer unit. The printing range of the small spot galvanometer unit covers the entire part, and the collection of the printing ranges of the large spot galvanometer units covers the entire part. During printing, the printing data of the outer surface of the part is assigned to the small spot galvanometer unit, and the printing data of the inner part of the part is assigned to the large spot galvanometer units. In this way, the splicing parts are all inside the shoe mold, and the outer surface is printed by one galvanometer unit without any splicing on the surface, which meets the requirements of very high surface quality requirements, very low surface roughness requirements, and low internal density requirements for the finished shoe mold.

[0024] 2. The metal 3D shoe mold printing method involved in the present invention distributes the printing data of the internal part of the part to the large light spot galvanometer units according to the principle of the same data volume, so that the scanning time of the large light spot galvanometer units is equal, so as to make the printing efficiency higher; when the printing data of the internal part of the part is distributed to the large light spot galvanometer units, the remelting area of ​​the adjacent large light spot galvanometer units is set, and the width of the remelting area is not less than the printing drift of the large light spot galvanometer unit. Even if the galvanometer becomes unstable, the internal splicing area will not be broken.

[0025] 3. In the metal 3D shoe mold printing method involved in the present invention, when the printing time of the small-spot galvanometer unit is less than the printing time of the large-spot galvanometer unit, the printing data of part of the internal part is allocated to the small-spot galvanometer unit, so that the printing time of the small-spot galvanometer unit is equal to the printing time of the large-spot galvanometer unit, thereby optimizing the printing speed. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A schematic diagram of the printing process of the metal 3D shoe mold printing method according to the present invention;

[0027] Figure 2 This is a schematic diagram of the splicing positions of each printing unit in the metal 3D shoe mold printing method involved in the present invention. DETAILED DESCRIPTION

[0028] In order to further understand the content of the present invention, the present invention is described in detail in conjunction with examples. The following examples are used to illustrate the present invention but are not used to limit the scope of the present invention.

[0029] Refer to the attached Figure 1 As shown, the present invention relates to a metal 3D shoe mold printing method, which comprises the following steps:

[0030] S1. Set a laser galvanometer group, which includes a small spot galvanometer unit 1 arranged in the center and a plurality of large spot galvanometer units 2 arranged around the small spot galvanometer unit 1; the printing range of the small spot galvanometer unit 1 covers the entire part, and the printing range of the large spot galvanometer unit 2 covers the entire part;

[0031] The small-spot galvanometer unit 1 uses a laser with a beam quality M2 less than 1.1 and a high beam quality. Since the shoe mold parts do not have too high requirements on the printing quality of the internal filling part, the large-spot galvanometer unit 2 can use a laser with poor beam quality, and a laser with a higher M2 can be used to reduce equipment costs.

[0032] S2. Assign the printing data of the external surface of the part to the small spot galvanometer unit 1, and assign the printing data of the internal part of the part to the large spot galvanometer units 2 according to the principle of the same data volume, ensuring that the printing time of each large spot galvanometer unit 2 is the same, such as Figure 2 As shown. For the large-spot galvanometer unit 2, a remelting area of ​​the adjacent large-spot galvanometer unit 2 is set, and the width of the remelting area is not less than the printing drift of the large-spot galvanometer unit. For example, if the long-term printing drift of the galvanometer of the large-spot galvanometer unit 2 is 0.5mm, then the width of the remelting area of ​​the printing data allocated to the adjacent large-spot galvanometer unit 2 is not less than 0.5mm. In this way, even if the galvanometer becomes unstable, the internal splicing area will not break. After allocating the printing data of the external surface of the part to the small-spot galvanometer unit 1 and the printing data of the internal part of the part to the large-spot galvanometer units 2, according to the printing data volume and printing speed of each galvanometer unit, the printing time of each large-spot galvanometer unit 2 is calculated as S1, and the printing time of the small-spot galvanometer unit 1 is calculated as S2. According to the printing time of the large-spot galvanometer unit and the small-spot galvanometer unit, the distribution amount of printing data is optimized, and the optimization method is:

[0033] When the printing time of the small-spot galvanometer unit 1 is not less than the printing time of the large-spot galvanometer unit 2, that is, when S2 ≥ S1, the distribution of the printing data of the outer surface of the part to the large-spot galvanometer unit 2 will cause the surface quality of the part to deteriorate. Therefore, the distribution amount of the printing data is not optimized in this case;

[0034] When the printing time of the small spot galvanometer unit 1 is less than the printing time of the large spot galvanometer unit 2, that is, when S2 is less than S1, the data volume of the small spot galvanometer unit 1 responsible for printing the outer surface of the part is too small, and the printing data of the internal part of the part needs to be allocated to the small spot galvanometer unit 1, and the printing data of part of the internal part is allocated to the small spot galvanometer unit 1, so that the printing time of the large spot galvanometer unit 2 and the printing time of the small spot galvanometer unit 1 after data allocation meet the following formula:

[0035]

[0036] Among them, S1′ and S2′ are the printing time of the small spot galvanometer unit and the large spot galvanometer unit after optimization, S1 and S2 are the printing time of the small spot galvanometer unit and the large spot galvanometer unit before optimization, N is the total number of small spot galvanometer units and large spot galvanometer units, and M means that the printing efficiency of the large spot galvanometer unit is M times that of the small spot galvanometer unit. At this time, S1′=S2′ is satisfied, and the time spent on printing data by the small spot galvanometer and the large spot galvanometer can be the same, achieving maximum printing efficiency.

[0037] According to the above allocation results, the parts are 3D printed.

[0038] The present invention is described in detail above in conjunction with the embodiments, but the contents described are only preferred embodiments of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made according to the scope of application of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A metal 3D shoe mold printing method, characterized in that: It includes the following steps: S1. Setting a laser galvanometer group, the laser galvanometer group includes a small spot galvanometer unit arranged in the center and a plurality of large spot galvanometer units arranged around the small spot galvanometer unit; the printing range of the small spot galvanometer unit covers the entire part, and the printing range of the large spot galvanometer unit covers the entire part; S2. Assign the printing data of the external surface of the part to the small spot galvanometer unit, and assign the printing data of the internal part of the part to the large spot galvanometer units, and perform 3D printing on the part.

2. The metal 3D shoe mold printing method according to claim 1, characterized in that: In the above S2, the printing data of the internal part of the part is distributed to each large spot galvanometer unit according to the principle of the same data amount.

3. The metal 3D shoe mold printing method according to claim 1, characterized in that: In S2, when the printing data of the internal part of the part is distributed to each large spot galvanometer unit, a remelting area of ​​adjacent large spot galvanometer units is set, and the width of the remelting area is not less than the printing drift of the large spot galvanometer unit.

4. The metal 3D shoe mold printing method according to claim 2, characterized in that: S2 allocates the printing data of the external surface of the part to the small spot galvanometer unit, allocates the printing data of the internal part of the part to the large spot galvanometer units, records the printing time of each large spot galvanometer unit as S1, and records the printing time of the small spot galvanometer unit as S2. According to the printing time of the large spot galvanometer unit and the small spot galvanometer unit, the distribution amount of the printing data is optimized, and the optimization method is: When the printing time of the small spot galvanometer unit is not less than the printing time of the large spot galvanometer unit, the distribution amount of the printing data is not optimized; When the printing time of the small spot galvanometer unit is less than the printing time of the large spot galvanometer unit, the printing data of part of the internal part is allocated to the small spot galvanometer unit, so that the printing time of the large spot galvanometer unit and the printing time of the small spot galvanometer unit after data allocation satisfy the following formula: Among them, S1′ and S2′ are the printing times of the small-spot galvanometer unit and the large-spot galvanometer unit after optimization, respectively; S1 and S2 are the printing times of the small-spot galvanometer unit and the large-spot galvanometer unit before optimization, respectively; N is the total number of the small-spot galvanometer unit and the large-spot galvanometer unit; and M indicates that the printing efficiency of the large-spot galvanometer unit is M times that of the small-spot galvanometer unit.

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