RU154761U1 - DEVICE FOR PRODUCING PRODUCTS FROM POWDERED MATERIALS - Google Patents

Abstract

A device for producing products from powdered materials, containing a rigid frame with a high-precision plate mounted on it with a base surface, a camera designed to protect service personnel, functionally connected control system and actuators, including a working hopper consisting of a piston with a heating element and mounted on top a substrate intended for layer-by-layer formation of the product, and a powder feed hopper, installed with the possibility of independent reciprocating movement relative to the upper plane of the high-precision plate, a hopper for collecting excess powder, a laser unit located above the bed with the possibility of focusing the laser beam in a technologically defined zone of product formation, and means for feeding and compaction of the powdered material in the form of a leveling knife, mounted with the possibility of horizontal reciprocating translational movement and formation of the product layer, characterized in that the laser unit is equipped with at least one optical range The operator associated with the control system and designed to control the level of the surface of the product in the zone of its formation.

Description

The utility model relates to powder metallurgy, in particular, to the technology of layer-by-layer synthesis of parts of complex spatial configuration from fine powder by the method of selective laser melting and / or sintering (SLP) using a computer 3-D model and can be used in various branches of mechanical engineering, for example, for manufacturing of heavy-duty, heat-resistant parts and assemblies.

The prior art device for the layered production of products from a powder material of the company Phenix System (France) (US Patent US7789037, B05C 13/00, 2006). According to the patent, the device consists of the following main parts:

- the machine part with the mechanisms and devices included in it;

- a laser with a scanning system;

- control system.

The machine part of the device is made in the form of a box structure with high rigidity for basing all other nodes. The machine part of the complex includes the following main components and equipment:

- frame;

- powder leveling device;

- working platform;

- powder feed device;

- sealed chamber (or oven);

- gas equipment and cooling;

- electrical equipment.

The frame mounted on the foundation is the base unit. It is a box-shaped structure consisting of square metal pipes. All basic units (sealed chamber, fencing chamber, etc.) are installed on the frame.

The fencing chamber consists of panels fixed outside the frame.

The powder leveling device reciprocates in the horizontal direction due to the electric drive. The main component of the powder leveling device is a roller with a V-neck. The cutout is located along the axis of rotation of the roller. The roller, making reciprocating movements, drags, levels and compacts the powder on the working platform. Powder material: any ceramic and metal powders (granule diameter 10-100 microns).

The working platform is fixed at the bottom of the high-precision plate of the powder leveling device. The working platform has the shape of a well, inside which the desktop moves up or down. On the desktop is the "growing" of the product. The table moves on four round guides with the help of a precision ball screw pair. Ball screw pair rotates by an electric motor. Desktop positioning accuracy ± 0.001 mm. The size of the working area: diameter 250 mm, height 300 mm, usable volume 1.5 l.

The powder feed device is attached to the bottom of the high precision plate of the powder leveling mechanism. The powder feeder has the shape of a well, inside of which the powder feeder table moves up or down. The powder feed table is driven on four circular guides using a precision ball screw pair. Ball screw pair rotates by an electric motor. Powder feed table positioning accuracy ± 0.001 mm.

A sealed chamber (or furnace) is fixed on top of a high-precision plate of the powder leveling mechanism. It forms a closed space into which gas can be supplied (argon, nitrogen, etc.). The space in the sealed chamber can heat up to 900 ° C.

Gas equipment and cooling. Gas equipment creates the necessary atmosphere in an airtight chamber (argon, nitrogen, etc.). The unit’s cooling system cools a 50 or 100 W fiber laser (depending on configuration).

The fiber laser is connected to a scanning system that allows you to control the laser beam in two spatial directions. Build speed: 1-10 mm ³ / sec.

The disadvantage of this device is the lack of control of the surface level of the product in the zone of its formation, which leads to uneven deposition of powder, which ultimately drastically reduces the quality of the manufactured product.

The technical problem to which the claimed utility model is aimed is to improve the quality of the product made by selective laser melting due to the uniform deposition of powder.

The technical result of the claimed utility model is to control the level of the surface of the product in the zone of its formation.

The claimed technical result obtained when solving the technical problem is achieved due to the fact that in the device for producing products from powder materials containing a rigid frame with a high-precision plate mounted on it with a base surface, a camera designed to protect service personnel, a working hopper, consisting of a piston with a heating element and a substrate fixed on top designed for layer-by-layer formation of the product, and a powder feed hopper, installed with an independent reciprocating movement relative to the upper plane of the high-precision plate, a hopper for collecting excess powder, a laser unit located above the bed with the ability to focus the laser beam in a technologically defined zone of product formation, means for feeding and compaction of the powdered material in the form of a leveling knife, installed with the possibility horizontal reciprocating movement and formation of the product layer, as well as a means of ensuring level control by the surface of the product, the means of ensuring surface control is an optical range finder mounted in the laser unit.

The essence of the claimed technical solution is as follows.

With selective laser melting, complete and / or partial melting of the powder particles by a laser beam occurs. The product is formed in layers. The thickness of the powder layer is one of the most important parameters. The vast majority of selective laser melting machines control the thickness of the deposited powder layers. The thickness of the layer is considered to be the amount of mixing of the working platform. This method does not take into account the unevenness of the deposition of the layer on the working platform and the amount of shrinkage of the material after laser exposure, which affects the thickness of the subsequent layers, and ultimately the quality of the product. The utility model is illustrated by graphic materials, where are schematically depicted in:

A device for producing products from powdered materials consists of the following main parts, components and equipment:

- frame 1;

- high precision plate 2;

- camera 3;

- working hopper 4;

- piston 5;

- substrate 6;

- hopper for collecting excess powder 7;

- leveling knife 8;

- powder feed hopper 9;

- laser unit 10;

- range finder 11;

- controller 12;

- piston drive 13.

Frame 1 (Fig. 1) is made in the form of a welded or prefabricated rigid box-shaped structure from square metal pipes. The frame is the basic unit for fixing the main parts, components and equipment of the installation.

A high-precision plate 2 (Fig. 1) is mounted on the frame 1 and contains a through hole 16 necessary for moving the substrate 6 together with the piston 5. Also, a hole 15 is provided in the high-precision plate 2 for pouring excess powder through it into the hopper for collecting excess powder 7 and a hole 16 for supplying portions of the powder hopper powder 9.

The chamber 3 is mounted on a high-precision plate 2. The chamber 3 is a prefabricated structure consisting of five walls that are closely adjacent to each other. The front of the camera is closed by two doors with glass protective windows. Camera 3 is necessary to protect personnel servicing the device for receiving products from powder material from powder particles, which when the device is turned into a suspension, to protect against laser radiation and moving parts of the device. Inside the chamber 3, it is possible to heat the working space to the required temperature in order to reduce the thermal gradient during the formation of the product. Heated workspace is carried out using a heating element 17 built into the piston 5.

The working hopper 4 is mounted on the lower plane 18 of the high-precision plate 2 and has the shape of a "well" of square cross section, inside of which the piston 5 can perform vertical reciprocating movement due to the drive of the piston 13. A substrate 6 is mounted on the piston 5, on which the product is formed. After the product is manufactured, it is removed from the device along with the substrate 6.

The hopper for collecting excess powder 7 is mounted on the lower plane 18 of the high-precision plate 2 and is designed to collect excess powder.

The leveling knife 8 is mounted cantilever on the rear wall of the chamber 3 and has the possibility of horizontal reciprocating movement parallel to the upper plane 19 of the high-precision plate 2 due to the rail type rail 20 and the electric drive (not shown in the figures).

The powder feed hopper 9 is designed to feed the working hopper 4 with new non-laser-treated powder batches that, when working together with a leveling knife 8, are spread in a thin layer on the surface of the substrate 6 (in the case of applying the first layer of powder), or on the surface of the previous layer previously processed powder.

The laser unit 10 is mounted on the upper wall of the chamber 3 and is necessary to ensure focusing of the laser beam 21 in the technologically specified zone of selective processing of each applied layer of powder during the formation of the product.

The optical range finder 11 has the shape of a parallelepiped and is mounted on the upper wall of the chamber 3, and has the ability to determine the distance to the surface at a certain point on the substrate 6. Determination of the distance can be carried out before applying the powder to the substrate 6, in order to determine and subsequently control the zero level of the substrate 6 and the upper plane 19 of the high-precision plate 2. Determining the value of the distance after applying the powder to the substrate 6, in order to determine and then control the thickness of the layer. Determining the distance after fusion of the powder on the substrate 6, in order to determine and subsequently control the zero level. Zero level control and control of the thickness of the powder is carried out by adjusting the position of the piston 5 based on the performance of the range finder sensor through the controller 12 (Fig. 1).

A device for producing products from powder materials works as follows.

In the automatic design system (CAD) create a three-dimensional computer 3D-model of the product and break it into cross-sections, which serve as the basis for the layered manufacturing of the product.

With technological need in the chamber 3, the working space is heated to the required temperature, usually 70-100 ° C, by the heating element 17 (Fig. 1).

The piston 5 is set to zero, the range finder 11 determines the distance, and in case of a mismatch, adjusts the position of the substrate 6 through the controller.

The piston 5 in the working hopper 4 is lowered down together with the substrate 6 by the size of the required layer of powder, which will be subjected to laser processing.

The powder supply hopper 9 raises a portion of the powder with the necessary margin above the upper plane 19 of the high-precision plate 2 (Fig. 1).

The leveling knife 8 located in the extreme right position moves to the left (Fig. 1 is shown by a dotted line). In the direction of travel, the knife rakes a portion of the powder over the powder feed hopper and, passing above the working platform, applies an even layer of powder to the substrate 6. Next, the range finder determines the distance to the powder surface, and in case of mismatch, the position of the piston 5 is adjusted and the leveling knife 8 reapplies or rakes powder depending on sensor readings. Leveling knife 8 dumps the remnants of excess powder into the hopper for collecting excess powder 7.

The leveling knife 8 returns to the rightmost position.

Through the tube (not shown in the figure), the space inside the frame 1 is filled with protective gas.

The laser beam 21, generated and controlled by the laser unit 10, selectively melts the applied powder layer according to the program.

The range finder 11 determines the distance to the remelted layer and, with the help of the controller, corrects the position for subsequent application of the powder.

Next, a new layer of powder is applied to the substrate 6 and the process is repeated until the product is completely manufactured. Moreover, the entire sequence of technological processes is carried out automatically in technologically regulated conditions by means of special software and hardware.

Thus, the claimed combination of features set forth in the utility model formula allows to increase the accuracy of the geometry of the product made by selective laser melting by improving the accuracy of the applied layers.

The analysis of the claimed technical solution for compliance with the conditions of patentability showed that the characteristics indicated in the independent claim are essential and interconnected with the formation of a stable set of necessary attributes unknown at the priority date from the prior art sufficient to obtain the desired technical result.

Thus, the above information indicates the fulfillment of the following set of conditions when using the claimed technical solution:

- the object embodying the claimed technical solution, in its implementation is intended to obtain products from powder materials of complex spatial configuration from fine powder by selective laser melting and / or sintering according to a computer 3-D model and can be used in various engineering industries, for example, manufacturing of heavy-duty, heat-resistant parts and assemblies.

- for the claimed object in the form as described in the independent clause of the formula below, the possibility of its implementation using the means and methods known from the prior art as described in the application on the priority date is confirmed;

- the object embodying the claimed technical solution, when implemented, is able to ensure the achievement of the technical result perceived by the applicant.

Therefore, the claimed subject matter meets the conditions of patentability “novelty” and “industrial applicability” under applicable law.

Claims (1)

A device for producing products from powdered materials, containing a rigid frame with a high-precision plate mounted on it with a base surface, a camera designed to protect service personnel, functionally connected control system and actuators, including a working hopper consisting of a piston with a heating element and mounted on top a substrate intended for layer-by-layer formation of the product, and a powder feed hopper, installed with the possibility of independent reciprocating movement relative to the upper plane of the high-precision plate, a hopper for collecting excess powder, a laser unit located above the bed with the possibility of focusing the laser beam in a technologically defined zone of product formation, and means for feeding and compaction of the powdered material in the form of a leveling knife, mounted with the possibility of horizontal reciprocating translational movement and formation of the product layer, characterized in that the laser unit is equipped with at least one optical range The operator associated with the control system and designed to control the level of the surface of the product in the zone of its formation.

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