A powder-free SLM 3D printer

Abstract

The present invention discloses a non-powder bed SLM 3D printer with a different location. The printer has a printing structure that is different from that of the existing traditional SLM 3D printer, that is, the transparent plate for placing powder is located above the laser, and the laser emits molten powder upward. A plurality of powder collection boxes are provided below the powder scraping device to meet the collection of different powders. The XY axis motion device of the powder spreading device can move along a predetermined trajectory according to the cross-sectional shape of the workpiece to perform customized powder spreading. The printer removes the powder bed, which reduces the work of powder collection. The powder spreading by the predetermined trajectory can reduce the waste of materials, which is simple and efficient.

Description

Technical Field

[0001] The invention relates to the technical field of metal additive manufacturing, and in particular to a powder-free bed-free SLM 3D printer. Background Art

[0002] 3D printing technology is an emerging additive manufacturing technology that uses a layer-by-layer material addition method to manufacture workpieces. Compared with traditional subtractive manufacturing, 3D printing technology has the advantages of low-cost manufacturing of complex objects, short product cycles, high-precision production, diversity of product types, personalized design, integrated molding and manufacturing of products, and unrestricted design of technology and form. The main 3D printing methods include fused deposition modeling (FDM), selective laser melting (SLM), laser stereolithography (SLA), digital light processing technology (DLP) and three-dimensional printing technology (3DP). Among them, selective laser melting (SLM) technology is the most widely used in metal 3D printing due to its good processing accuracy and adaptability.

[0003] The powder bed of traditional SLM 3D printers is at the bottom. Each time a print is made, the height of the powder bed must be lowered and the powder must be spread again. After printing, the workpiece is buried under the heavy powder and needs to be cleaned manually. The traditional way to clean SLM printers is to use a special vacuum cleaner to manually suck the powder from the powder bed, which will cause additional manual operations, increase costs, and there is also the problem of incomplete cleaning. In addition, when performing multi-material printing, various powders are mixed together, affecting the recycling of unprinted materials. Therefore, it is urgent to design an SLM printing device without a powder bed or one that is easy to clean and recycle powder. Summary of the invention

[0004] The purpose of the present invention is to provide a powder-free SLM 3D printer with an alternative position.

[0005] The technical solution provided by the present invention is: a powder-free bed-mounted SLM 3D printer, which mainly includes a laser printing device, a powder scraping device, a powder spreading device, a protective gas adding device and a multi-purpose manipulator.

[0006] The laser printing device is located on one side of the molding room, the powder scraping device is located on the right side of the laser printing device, the powder spreading device is located on the right side of the powder scraping device, the multi-purpose manipulator is located in the middle of the molding room, and the protective gas adding device is located outside the molding room.

[0007] The laser printing device of the 3D printer in the above technical solution is opposite to the traditional SLM printer in terms of longitudinal structure, and adopts a displaced printing method. The laser is located below the 3D printer, and the laser emitted from the laser is reflected by the galvanometer and then emitted upward. The transparent plate is located above the laser source, and the transparent plate is supported by an adjustable support frame, and the laser reflected by the galvanometer passes upward through the transparent plate.

[0008] The laser printing device comprises a laser, a galvanometer, a transparent plate, a support frame, a substrate and a hydraulic cylinder from bottom to top. The hydraulic cylinder is connected to the upper part of the molding chamber. The substrate and the hydraulic cylinder are connected by electromagnetic adsorption. The hydraulic cylinder adjusts the height of the substrate so that the substrate reaches a suitable height from the transparent plate for printing.

[0009] The powder scraping device includes a powder scraping device housing, a scraper and a powder collecting box. The powder collecting box is located below the molding chamber and is connected to the upper part of the powder scraping device through an opening at the bottom of the molding chamber. The scraper is driven by motors on both sides of the scraper to scrape powder.

[0010] The powder spreading device is composed of a multi-material powder spreading device and an XY axis motion device, and a transparent plate placement rack is installed on the XY axis motion device. The multi-material powder spreading device is located above the XY axis motion device, and the multi-material powder spreading device is connected to the upper part of the molding chamber through a second hydraulic cylinder.

[0011] Furthermore, the XY axis motion device drives the transparent plate to move to complete the powder spreading, and the multi-material powder spreading device adjusts the distance from the transparent plate through the second hydraulic cylinder.

[0012] Furthermore, the multi-purpose manipulator can perform lifting, rotating and clamping operations, thereby completing the transfer of the transparent plate.

[0013] Furthermore, the protective gas adding device includes a gas storage tank and an air pump. The protective gas device is connected to the molding chamber through an air inlet and an air outlet, and the filling of protective gas and the suction of air in the molding chamber are completed by the air pump.

[0014] A transparent plate storage device may also be added to the technical solution to improve printing efficiency.

[0015] The present invention has the following beneficial effects:

[0016] By using the laser-upward printing method, the SLM 3D printer avoids the phenomenon of large amounts of powder accumulation on the powder bed, greatly reduces the powder cleaning work after printing, reduces the number of manual interventions, and greatly improves the working efficiency of the SLM 3D printer.

[0017] Customized powder spreading can be achieved by driving the transparent plate through the XY axis motion device. Powder spreading can be performed locally according to the shape of the printed workpiece cross section, greatly reducing powder consumption.

[0018] Multiple powder collection boxes can effectively complete the recycling and reuse of multi-powder printing, improve resource utilization, save costs, and avoid the difficulty of powder recycling when traditional 3D printers print multi-material workpieces. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 For the whole SLM 3D printer;

[0020] Figure 2 This is a diagram of a laser printing device;

[0021] Figure 3 This is a diagram of a powder scraping device;

[0022] Figure 4 This is a diagram of the powder spreading device;

[0023] Figure 5 This is a diagram of a multi-purpose manipulator;

[0024] In the figure, 1, laser printing device 2, powder scraping device 3, powder spreading device 4, multi-purpose manipulator 5, protective gas adding device 6, molding chamber 11. substrate 12, transparent plate 13, laser transmitter 14, galvanometer 15, support frame 16, electromagnetic adsorption device 17, hydraulic cylinder 1 21, powder scraping device housing 22, screw transmission device 23, powder collection box placement plate 24, powder collection box 25, powder scraping knife 31, transparent plate placement frame 32, hydraulic cylinder 2 33, multi-material powder spreading device 34, XY axis motion device 41, chassis 42, manipulator clamping device 43, mechanical arm 44, screw lifting device DETAILED DESCRIPTION

[0025] It should be noted that, in the present invention, the directions or positional relationships indicated by terms such as "up", "down", "left", "right", etc. are based on the directions or positional relationships shown in the accompanying drawings. They are relational words determined only for the convenience of describing the structural relationships of the various components of the present invention. They do not specifically refer to any component in the present invention and should not be understood as limitations on the present invention.

[0026] The specific embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings:

[0027] Please refer to Figure 1As shown, the present invention discloses a non-powder bed SLM 3D printer, which mainly includes a laser printing device 1, a powder scraping device 2, a powder spreading device 3, a multi-purpose manipulator 4, a protective gas adding device 5 and the like. The laser printing device 1 adopts a laser upward printing method, and the laser melts the powder through a transparent plate. The powder barrel collection box 24 of the powder scraping device 2 is located below the molding chamber and is connected to the powder scraping device 2 through a through hole. The powder spreading device 3 can drive the transparent plate 12 to perform track motion through the XY axis motion device 34 to selectively spread powder.

[0028] When printing starts, the multi-purpose robot 4 takes the transparent plate 12 away from the powder spreading device 3 and places it on the support frame 15. The hydraulic cylinder 17 adjusts the height of the substrate 11 so that the substrate 11 and the powder on the transparent plate 12 are in contact. Further, the laser 13 starts to work, and the emitted laser is reflected by the galvanometer 14 and then emitted upward. The laser passes through the transparent plate 12 to melt the powder and print it on the substrate 11.

[0029] Furthermore, after printing is completed, the hydraulic cylinder 17 moves upward to separate the substrate 11 from the transparent plate 12, and the multi-purpose manipulator 4 transfers the transparent plate 12 to the powder scraping device 2. The scraper 25 of the powder scraping device 2 is driven by a motor to hang down the powder on the transparent plate 12, and the scraped powder falls into the powder collecting box 24 under the molding chamber 6 to complete the powder collection. According to the changes in the scraped powder, the screw transmission device 22 drives the powder collection box placement plate 23 to move to select a suitable powder collection box.

[0030] Furthermore, after the powder scraping is completed, the multi-purpose manipulator 4 transfers the transparent plate 12 to the transparent plate placement rack 31 of the XY-axis motion device 34, and the hydraulic cylinder 2 32 adjusts the height of the multi-material powder spreading device, and then spreads the powder at a suitable height from the transparent plate. The XY-axis motion device 34 drives the transparent plate 12 to perform trajectory motion to complete the powder spreading.

[0031] Furthermore, the multi-purpose robot 4 transfers the transparent plate to the support frame 15 of the laser printing device 1 for the next printing.

[0032] In order to facilitate those skilled in the art to better understand the present invention, the present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, but the practical application of the present invention is not limited to the listed embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present invention.

Claims

1. A powder-free bed-free SLM 3D printer, characterized in that: The non-powder bed-mounted SLM 3D printer comprises: a laser printing device, a powder scraping device, a powder spreading device, a protective gas adding device and a multi-purpose manipulator; the laser printing device is arranged in a non-positioned printing manner, and comprises a laser, a galvanometer, a transparent plate, a support frame, a substrate and a hydraulic cylinder 1 from bottom to top, wherein the laser is emitted upward after being deflected by the galvanometer, the transparent plate is located above the laser, and the position of the support frame is adjusted according to the size of the transparent plate; the hydraulic cylinder 1 adopts electromagnetic adsorption to adsorb the substrate at the bottom; the powder scraping device comprises a powder scraping device housing, a scraper and a powder collecting box, the powder collecting box is located below the molding chamber, and is connected to the upper part of the powder scraping device through the opening at the bottom of the molding chamber, and the scraper is driven by the motors on both sides of the scraper to scrape powder; the powder spreading device comprises a multi-material powder spreading device and an XY axis motion device, a transparent plate placing frame is installed on the XY axis motion device, the multi-material powder spreading device can add powder to the multi-material powder spreading device according to printing needs for mixing and then spreading powder, and the multi-material powder spreading device is height-adjusted by a hydraulic cylinder 2.

2. A powder-free bed-free SLM 3D printer according to claim 1, characterized in that The powder scraping device is equipped with multiple powder collecting boxes, and the positions of the powder collecting boxes are adjusted according to the changes in the printing materials.

3. A powder-free bed-free SLM 3D printer according to claim 2, characterized in that The powder collecting box is adjusted by being placed on a powder collecting box placement plate.

4. The powder-free bed-free SLM 3D printer according to claim 1, characterized in that The XY axis motion device drives the transparent plate to move along a predetermined trajectory to complete the customized powder spreading.

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