3D printed composite sand mould

Abstract

The utility model discloses a 3D printing combined sand mould belongs to sand mould foundry technical field, including multilayerly stacked sand mould, and the sand mould includes the upper sand box and lower sand box of forming cavity, is equipped with the positioning structure between two adjacent sand moulds, and the outer surface of sand mould is equipped with fastening structure, and the pouring assembly includes the straight runner of all sand moulds, is equipped with the cross runner on the straight runner, and the cross runner is communicated to have the cavity runner, and the cavity runner is communicated with the cavity, and the communication of straight runner and cross runner, the communication of cross runner and cavity runner all forms the corner, and the runner nest is equipped with in the communication of straight runner and cross runner, the utility model discloses a plurality of sand moulds stacked realizes small -size casting multiple piece synchronous pouring, improves production efficiency, and solves the contradiction between large -scale smelting furnace, large ladle and small -size casting production, and the positioning structure and fastening structure guarantee the positioning accuracy and stability between a plurality of sand moulds, guarantee foundry quality, and the cross runner and cavity runner in pouring assembly improve the uniformity and stability of filling.

Description

Technical Field

[0001] This utility model relates to the field of sand casting technology, specifically to a 3D printed composite sand mold. Background Technology

[0002] At present, the casting production of small castings faces multiple challenges, mainly in terms of the adaptability of production equipment and the complexity of casting design. Specifically, firstly, the design capacity of traditional large melting furnaces and large steel ladles far exceeds the actual needs of small castings, making it difficult to accurately control the pouring volume, resulting in energy waste and process instability. Secondly, small castings are diverse in type and structure, requiring frequent adjustments to the design scheme, which greatly increases the design workload. This includes issues such as the process implementation of complex internal cavity structures, high-precision surface quality requirements, and the production organization of diversified products. These factors together restrict the production efficiency and product quality of small castings.

[0003] Although conventional combined sand box structures can solve the above problems to some extent, there are still issues such as complex pouring system structure, unreasonable gating channel design, and cumbersome and inaccurate sand mold positioning process.

[0004] Therefore, developing a 3D-printed composite sand mold that can effectively resolve the contradiction between large smelting furnaces and the production of large steel ladles and small castings, improve production efficiency, have a reasonable gating system, ensure uniform filling, improve casting effect, and automatically center during assembly and positioning is an urgent problem to be solved at this stage. Summary of the Invention

[0005] To address the problems existing in the prior art, this utility model provides a 3D printed composite sand mold that stacks multiple sand molds to achieve a simultaneous casting process for multiple small castings. This improves production efficiency while resolving the contradiction between large melting furnaces and large steel ladles and the production of small castings. The positioning and fastening structures ensure the positioning accuracy and stability between multiple sand molds, guaranteeing casting quality. At the same time, the use of the horizontal sprue and the inlet sprue in the casting assembly improves the uniformity and stability of filling, enhancing the casting effect.

[0006] To achieve the above objectives, the technical solution adopted by this utility model is as follows: This utility model provides a 3D printed composite sand mold, comprising: A multi-layered sand mold, comprising an upper sand box and a lower sand box forming a cavity; a positioning structure is provided between the contact surfaces of two adjacent sand molds; a fastening structure is provided on the outer surface of the sand mold; the sand mold is manufactured using 3D printing. A casting assembly includes a sprue that penetrates all the sand molds. A horizontal gating is provided at each location of the sprue corresponding to the sand mold. The horizontal gating connects to a cavity gating, which is connected to the mold cavity. An angle is formed at the connection points between the sprue and the horizontal gating, and between the horizontal gating and the cavity gating. A gating recess is provided on the sprue below the connection point between the sprue and the horizontal gating.

[0007] As a preferred technical solution, in two adjacent sand molds, the upper surface of the upper sand box of the lower sand mold is provided with a first positioning part, and the lower surface of the lower sand box of the upper sand mold is provided with a second positioning part that matches the first positioning part. The first positioning part and the second positioning part form the positioning structure.

[0008] As a preferred technical solution, the first positioning part is configured as a positioning groove, and the second positioning part is configured as a positioning protrusion that matches the positioning groove.

[0009] As a preferred technical solution, the cross-section of the positioning protrusion is set as a polygon; And / or, the sidewall of the positioning protrusion is inclined inward in a direction away from the lower surface of the lower sand box, the angle between the sidewall of the positioning protrusion and the vertical plane is set to 10°-20°, and the shape of the sidewall of the positioning groove matches the positioning protrusion.

[0010] As a preferred technical solution, the fastening structure includes a channel steel and a fastening sub-groove provided on the side wall of the sand mold. The fastening sub-grooves on multiple layers of the sand mold are connected in sequence to form a fastening groove, and the channel steel is fixed in the fastening groove.

[0011] As a preferred technical solution, the connection between the horizontal runner and the inlet runner is located at the end of the horizontal runner that is furthest from the vertical runner.

[0012] As a preferred technical solution, the sand mold is provided with a riser cavity, the riser cavities of the multiple layers of the sand mold are connected in sequence, and the upper surface of the upper sand box of the uppermost sand mold has a riser that communicates with the riser cavity.

[0013] As a preferred technical solution, the direct pouring channel is located at the center of the sand mold; And / or, the horizontal gating system is located on both sides of the vertical gating system, and the cavity inlet gating system is located on both sides of the horizontal gating system; And / or, the cross-section of the inlet gating system is a flat trapezoidal shape.

[0014] As a preferred technical solution, the sand mold is provided with hanging handles on its opposite sides.

[0015] As a preferred technical solution, the shapes of the cavities within different sand molds can be set to be the same or different.

[0016] The beneficial effects of this utility model are as follows: 1. This utility model stacks multiple sand molds, transforming the original single-piece casting with a weight of less than 100kg into multi-piece casting with a weight of 500kg-1T. This enables simultaneous casting of multiple small castings, improving production efficiency while resolving the contradiction between large melting furnaces and large steel ladles and the production of small castings. The positioning and fastening structures effectively ensure the positioning accuracy and stability between multiple sand molds, guaranteeing casting quality. At the same time, the use of the horizontal runner and the inlet runner in the casting assembly improves the uniformity and stability of filling, enhancing the casting effect.

[0017] 2. The sidewall of the positioning protrusion of the positioning structure of this utility model is set as an inclined surface, which not only enables automatic centering during the assembly positioning process and ensures positioning accuracy, but also expands the contact area between adjacent sand molds, making the force more uniform and avoiding gravity deformation of the bottom sand mold.

[0018] 3. The riser of this utility model connects all the sand molds. After the molten metal enters the mold cavity, liquid can be replenished and air can be vented through the riser, which can effectively improve the feeding and venting effect.

[0019] 4. Based on the weight and structure of the casting, this utility model designs a universal and standardized pouring component, and the inlet gating channel of the pouring component forms an inner gating channel; at the same time, standardized 3D printed sand molds are used, and the external dimensions of the sand molds for different castings are consistent, and the sand mold docking structure is the same, which is convenient for stacking and assembly. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall structure of one embodiment of a 3D printed composite sand mold according to the present invention; Figure 2 for Figure 1 Top view; Figure 3 for Figure 2 Sectional view along the middle AA direction; Figure 4 for Figure 1 A schematic diagram of the structure of a sand mold; Figure 5 for Figure 1 A schematic diagram of the casting component.

[0021] In the diagram: 1-Sand mold, 11-Upper sand box, 12-Lower sand box, 13-Cavity, 14-Positioning groove, 15-Positioning protrusion, 16-Securing groove, 17-Riser mouth, 18-Riser, 19-Hanging handle, 21-Straight sprue, 22-Horizontal sprue, 23-Entry sprue, 24-Sprue recess. Detailed Implementation

[0022] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to the accompanying drawings.

[0023] Please refer to Figures 1-5 This invention provides a first embodiment of a 3D printed composite sand mold, comprising a casting assembly and two sand molds 1 stacked vertically; each sand mold 1 includes an upper sand box 11 and a lower sand box 12, which form a cavity 13; a positioning structure is provided between the contact surfaces of two adjacent sand molds 1, which can accurately position the two sand molds 1; a fastening structure is provided on the outer surface of the sand mold 1, which can lock and fix the two sand molds 1; the main body of the casting assembly is located inside the sand mold 1, and the casting assembly includes a sprue 21 that penetrates all the sand molds 1, and a horizontally arranged transverse sprue 22 is provided at each sand mold 1 corresponding to the sprue 21, the transverse sprue 22 being connected to... The inlet gating 23 is connected to the mold cavity 13. The molten metal flows into the mold cavity 13 after passing through the sprue 21, the runner 22, and the inlet gating 23 in sequence. The connection between the sprue 21 and the runner 22, and the connection between the runner 22 and the inlet gating 23, form corners to reduce turbulence of the molten metal. A gating recess 24 is provided on the sprue 21 below the connection between the sprue 21 and the runner 22. The gating recess 24 serves as a buffer area for the molten metal to change from vertical to horizontal flow. The two-stage gating recess 24 can also adjust the filling speed and reduce sand washing defects. In addition, the gating recess 24 reduces the flow rate of the molten metal and works with the slag blocking function of the inlet gating 23 to eliminate the need for a filter in this casting assembly.

[0024] In other embodiments, the number of sand molds 1 stacked can also be three or more, to meet the actual needs of simultaneous casting of multiple small castings.

[0025] Please refer to the following for clarification: Figure 4 Each sand mold 1 contains multiple cavities 13, which are evenly distributed around the center of the sand mold 1. Furthermore, the shapes of the cavities 13 in different sand molds 1 can be the same or different, so that different castings can be cast. Furthermore, the sand mold 1 is 3D printed, so that the external dimensions of the sand mold 1 of different castings are consistent, and the positioning and fastening structures of the sand mold 1 of different castings are the same, which can easily realize the stacking and assembly of sand molds 1 of different castings.

[0026] Specifically, please refer to Figure 5 The sprue 21 is located at the center of the sand mold 1, the gating 22 is located on both sides of the sprue 21, and the inlet gating 23 is located on both sides of the gating 22. This ensures that the molten metal flows evenly into each cavity 13, reduces casting defects, reduces casting time and oxidation turbulence, and ensures uniform temperature distribution. Compared with the prior art where the sprue 21 is located on the outside of the sand mold 1 and the gating 22 is located at the bottom of the sprue 21, and the molten metal enters the cavity 13 from bottom to top through the gating 22 and then through the inlet gating, the molten metal filling capacity of this embodiment is better and facilitates sequential solidification.

[0027] Further, please refer to Figure 5 The cross-section of the inlet gating channel 23 is preferably in the shape of a flat trapezoid, which has the advantages of low flow resistance and uniform heat conduction.

[0028] Additionally, please refer to Figure 5 The connection between the horizontal sprue 22 and the inlet sprue 23 is located at the end of the horizontal sprue 22 that is far from the straight sprue 21. There is a distance between the end of the inlet sprue 23 and the end of the horizontal sprue 22. The end of the horizontal sprue 22 can accommodate some slag and air under the filtration of the flat trapezoidal shape of the inlet sprue 23, and can improve the thermal balance of the sand mold 1, reducing defects such as shrinkage cavities and air holes caused by uneven temperature of the sand mold 1.

[0029] In this embodiment, please refer to Figure 3 and Figure 4 In two adjacent sand molds 1, the upper surface of the upper sand box 11 of the lower sand mold 1 is provided with a first positioning part, and the lower surface of the lower sand box 12 of the upper sand mold 1 is provided with a second positioning part that matches the first positioning part. The first positioning part and the second positioning part form a positioning structure. When the upper sand mold 1 is placed on the lower sand mold 1, the first positioning part and the second positioning part automatically match, so that the two sand molds 1 can be accurately positioned.

[0030] Specifically, please refer to Figure 3 and Figure 4 The first positioning part is set as a positioning groove 14, and the second positioning part is set as a positioning protrusion 15 that matches the positioning groove 14; in other embodiments, the first positioning part can also be set as a positioning protrusion 15, and correspondingly, the second positioning part can be set as a positioning groove 14; or, the first positioning part and the second positioning part can be set as a matching male and female snap structure, so that the first positioning part and the second positioning part automatically cooperate to accurately position the upper and lower sand molds 1.

[0031] Further, please refer to Figure 4 The cross-section of the positioning protrusion 15 is set as a polygon, which matches the shape of the sand mold 1 for easy processing and use; in other embodiments, the cross-section of the positioning protrusion 15 can also be elliptical, curved polygon, etc., as long as it can achieve the positioning of the two sand molds 1.

[0032] Furthermore, please refer to Figure 4 The sidewall of the positioning protrusion 15 is inclined inward in the direction away from the lower surface of the lower sand box 12. The angle between the sidewall of the positioning protrusion 15 and the vertical plane is set to 10°-20°. The shape of the sidewall of the positioning groove 14 matches the positioning protrusion 15. During the assembly and positioning process, the positioning protrusion 15 and the positioning groove 14 can achieve automatic centering and ensure positioning accuracy. In addition, the inclined sidewall of the positioning protrusion 15 increases the contact area between adjacent sand molds 1, making the force between sand molds 1 more uniform and effectively preventing the bottom sand mold 1 from undergoing gravity deformation.

[0033] In this embodiment, please refer to Figure 1 , Figure 2 and Figure 4 The fastening structure includes channel steel and fastening sub-grooves 16 on the side wall of sand mold 1. The fastening sub-grooves 16 on the multi-layer sand mold 1 are connected in sequence to form a fastening groove. After the channel steel on the opposite sides of the sand mold 1 is embedded in the fastening groove, the channel steel on both sides is connected by bolts and screws to fasten the sand mold 1. The traditional method of filling sand with a sand box is no longer needed to achieve fixation.

[0034] Further, please refer to Figures 1-4 Each side of the sand mold 1 is equipped with a hanging handle 19 for easy transport and assembly.

[0035] In this embodiment, please refer to Figure 1 and Figure 4 Sand mold 1 is provided with riser cavity 17. The riser cavity 17 of the multi-layer sand mold 1 are connected in sequence. The upper surface of the upper sand box 11 of the uppermost sand mold 1 has a riser 18 that communicates with the riser cavity 17. Combined with the straight sprue 21 set in the center, after the molten metal enters the cavity 13, it can be replenished and vented through the riser 18. Specifically, the riser 18 and the sand mold 1 are manufactured together using 3D printing technology. After the cavity 13 of the sand mold 1 of different castings is coated with casting coating, they can be stacked and assembled.

[0036] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. For those skilled in the art, the present utility model can have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A 3D printed composite sand mold, characterized in that, include: A multi-layered sand mold (1) includes an upper sand box (11) and a lower sand box (12), which together form a cavity (13); a positioning structure is provided between the contact surfaces of two adjacent sand molds (1); a fastening structure is provided on the outer surface of the sand mold (1); the sand mold (1) is 3D printed. The casting assembly includes a sprue (21) that penetrates all the sand molds (1). The sprue (21) is provided with a horizontal runner (22) for each sand mold (1). The horizontal runner (22) is connected to an inlet runner (23) and the inlet runner (23) is connected to the cavity (13). The connection between the sprue (21) and the horizontal runner (22) and the connection between the horizontal runner (22) and the inlet runner (23) form a corner. A runner recess (24) is provided on the sprue (21) below the connection between the sprue (21) and the horizontal runner (22).

2. The 3D printed composite sand mold according to claim 1, characterized in that, In two adjacent sand molds (1), the upper surface of the upper sand box (11) of the lower sand mold (1) is provided with a first positioning part, and the lower surface of the lower sand box (12) of the upper sand mold (1) is provided with a second positioning part that matches the first positioning part. The first positioning part and the second positioning part form the positioning structure.

3. The 3D printed composite sand mold according to claim 2, characterized in that, The first positioning part is configured as a positioning groove (14), and the second positioning part is configured as a positioning protrusion (15) that matches the positioning groove (14).

4. A 3D printed composite sand mold according to claim 3, characterized in that, The cross-section of the positioning protrusion (15) is set as a polygon; And / or, the sidewall of the positioning protrusion (15) is inclined inward in a direction away from the lower surface of the lower sand box (12), the angle between the sidewall of the positioning protrusion (15) and the vertical plane is set to 10°-20°, and the shape of the sidewall of the positioning groove (14) matches the positioning protrusion (15).

5. A 3D printed composite sand mold according to claim 1, characterized in that, The fastening structure includes a channel steel and a fastening sub-groove (16) provided on the side wall of the sand mold (1). The fastening sub-groove (16) on multiple layers of the sand mold (1) are connected in sequence to form a fastening groove, and the channel steel is fixed in the fastening groove.

6. A 3D printed composite sand mold according to claim 1, characterized in that, The connection between the horizontal runner (22) and the cavity runner (23) is located at the end of the horizontal runner (22) that is away from the vertical runner (21).

7. A 3D printed composite sand mold according to claim 1, characterized in that, The sand mold (1) is provided with a riser cavity (17), and the riser cavities (17) of the multiple layers of the sand mold (1) are connected in sequence. The upper surface of the upper sand box (11) of the uppermost sand mold (1) has a riser (18) that is connected to the riser cavity (17).

8. A 3D printed composite sand mold according to claim 1, characterized in that, The direct pouring channel (21) is located at the center of the sand mold (1); And / or, the horizontal gating (22) is located on both sides of the vertical gating (21), and the cavity gating (23) is located on both sides of the horizontal gating (22); And / or, the cross-section of the inlet gating system (23) is a flat trapezoidal shape.

9. A 3D printed composite sand mold according to claim 1, characterized in that, Each of the sand molds (1) has a hanging handle (19) on its opposite side.

10. A 3D printed composite sand mold according to claim 1, characterized in that, The shapes of the cavities (13) in different sand molds (1) can be the same or different.

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