Precoated sand shell mold casting mold

Abstract

According to the precoated sand shell mold casting mold, forming cavities are formed in main shells, a pouring gate is arranged in a pouring gate shell, two sets of main shells are arranged to be connected with the pouring gate shell, the forming cavities in the two main shells communicate with the pouring gate of the pouring gate shell through a feeding port, two products can be cast through one pouring gate, the production efficiency is high, and after forming, the product quality is improved. According to two products, only metal residues in one pouring gate need to be cut off, resource loss is greatly reduced, the feeding head communicated with the pouring gate and the forming cavity is formed below the feeding port, in the cooling process of the metal liquid in the forming cavity, when mold shrinkage occurs due to thermal expansion and cold contraction, the metal liquid can be continuously supplemented into the forming cavity, and the mold shrinkage rate is increased. And the problem of internal defects of the product is solved, the product structure is complete, and the rejection rate during product forming is greatly reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of automobile parts production, and relates to a sand casting mould, in particular to a coated sand shell casting mould. Background Art

[0002] Sand casting is to make a mold with sand. It is necessary to put the finished part model or wooden model in the sand, and then fill the sand around the pattern. After the pattern is taken out of the box, the sand forms a mold. In order to remove the model before casting the metal, the mold should be made into two or more parts. During the mold making process, holes must be left for pouring metal into the mold to form a pouring system. After the mold is poured with liquid metal, it is kept for a suitable time until the metal solidifies. After the part is taken out, the mold is destroyed, so a new mold must be made for each casting. It is low-cost and can produce parts of various sizes.

[0003] Traditional sand casting molds usually have one model cavity and one runner, which has low production efficiency. When the product is formed, the residual metal liquid in the runner will be cut and processed after solidification, resulting in a waste of production resources. When the metal liquid in the model cavity cools and solidifies, it is easy to cause mold shrinkage due to thermal expansion and contraction, resulting in a high scrap rate when complex structures are formed. Summary of the invention

[0004] In order to solve the technical problems existing in the background technology, the present invention proposes a coated sand shell casting mold, which realizes the casting of two products through one runner and can continuously replenish metal liquid when the mold shrinks, so that the product structure is complete, greatly reducing the scrap rate during product molding.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] A coated sand shell casting mold comprises: a runner shell, two groups of main shells, and two groups of top shells. The two groups of main shells are arranged opposite to each other, the main shells have a first end face and a second end face, and a molding cavity connecting the first end face and the second end face is provided in the main shell. The two groups of top shells are respectively adapted to be connected with the first end faces of the two groups of main shells to block the molding cavity from the first end face side. The runner shell is connected between the two groups of main shells, and the two first end walls of the runner shell are respectively adapted to be connected with the second end faces of the two groups of main shells to block the molding cavity from the second end face side. The runner shell has a runner, and the two first end walls of the runner shell are both provided with a feed port to connect the runner with the molding cavities of the two main shells, and a shrinkage feed riser connecting the runner and the molding cavity is also provided below the feed port.

[0007] Furthermore, a first end face of the main shell is provided with an annular first pressure edge portion arranged along the edge of the first end face, the top shell is inserted into the first pressure edge portion and connected to the first end face, a second end face of the main shell is provided with an annular second pressure edge portion arranged along the edge of the second end face, and the first end wall of the runner shell is inserted into the second pressure edge portion and connected to the second end face.

[0008] Further, the runner is axially parallel and arranged between two first end walls of the runner shell, and the runner extends axially upward to form a runner extension tube at the top of the runner shell.

[0009] Furthermore, the diameter of the runner extension pipe gradually increases from the runner to a direction away from the runner.

[0010] Furthermore, a cavity is provided between the side wall of the runner and the side wall of the runner shell, and an air port communicating with the cavity is provided on the side wall of the runner shell.

[0011] Furthermore, two exhaust pipes are arranged along the extending direction of the runner extension pipe at the top of the main shell, and the bottom of the exhaust pipe is communicated with the top of the molding cavity.

[0012] Furthermore, the exhaust pipe is arranged at the connection between the main shell and the runner shell. The exhaust pipe is a long U-shaped open groove. There are baffles on both sides of the runner extension pipe. The baffles are connected to and sealed on one side of the opening of the exhaust pipe.

[0013] Furthermore, a third elongated edge pressing portion is provided on one side of the exhaust pipe, and two ends of the baffle are clamped between the third edge pressing portions of the two exhaust pipes on the main shell.

[0014] Furthermore, the runner shell is composed of two relatively arranged first half shells and a second half shell connected to each other, a first half runner groove is opened on the first half shell, a second half runner groove is opened on the second half shell, a fourth pressure edge portion is arranged along the edge of the first half runner groove on the side wall, and the side wall of the second half runner groove is inserted into the fourth pressure edge portion and connected to the side wall of the first half runner groove.

[0015] The beneficial effects of the present invention are as follows: the coated sand shell casting mold provided by the present application has a molding cavity arranged in the main shell, and a runner arranged in the runner shell. By arranging two groups of main shells to connect the runner shells, the molding cavities in the two main shells are connected with the runner of the runner shell through a feed port, thereby realizing the casting of two products by one runner, with high production efficiency. Moreover, after molding, only the metal residue in one runner needs to be cut off for the two products, thereby greatly reducing the loss of resources. By opening a shrinkage feed riser connecting the runner and the molding cavity below the feed port, when shrinkage occurs due to thermal expansion and contraction during the cooling process of the metal liquid in the molding cavity, the metal liquid can be continuously added to the molding cavity, thereby improving the internal defects of the product, making the product structure complete, and greatly reducing the scrap rate during product molding. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a three-dimensional schematic diagram of the present invention.

[0017] Figure 2 Schematic diagram of the top shell of the present invention.

[0018] Figure 3 It is a schematic diagram of the first end surface direction of the main shell of the present invention.

[0019] Figure 4 It is a schematic diagram of the second end surface direction of the main shell of the present invention.

[0020] Figure 5 It is a schematic diagram of the assembly of the main shell and the runner shell of the present invention.

[0021] Figure 6 It is a schematic diagram of the runner shell of the present invention.

[0022] Figure 7 It is a schematic diagram of the first half shell of the present invention.

[0023] Figure 8 Schematic diagram of the second half shell of the present invention. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] like Figure 1-5 As shown, the present invention provides a coated sand shell type casting mold, comprising: a runner shell 1, two groups of main shells 2, and two groups of top shells 3. The two groups of main shells 2 are arranged opposite to each other, the main shells 2 have a first end face 21 and a second end face 22, and a molding cavity 23 connecting the first end face 21 and the second end face 22 is provided in the main shell 2. The two groups of top shells 3 are respectively adapted to be connected with the first end faces 21 of the two groups of main shells 2 to block the molding cavity 23 from one side of the first end face 21. The runner shell 1 is connected between the two groups of main shells 2, and the two first end walls 11 of the runner shell 1 are respectively connected with the two groups of main shells 2. The second end face 22 is adapted to be connected to block the molding cavity 23 from one side of the second end face 22. The runner shell 1 has a runner 12. The two first end walls 11 of the runner shell 1 are each provided with a feed port 4 to connect the runner 12 with the molding cavities 23 of the two main shells 2. The molding cavities 23 in the two main shells 2 are both connected to the runner 12 of the runner shell 1 through a feed port 4, thereby realizing the casting of two products by one runner 12, with high production efficiency. After molding, only the metal residue in one runner 12 needs to be cut off for the two products, thereby greatly reducing the loss of resources.

[0026] A feeding riser 5 connecting the runner 12 and the molding cavity 23 is also provided below the feed port 4. By providing the feeding riser 5 connecting the runner 12 and the molding cavity 23 below the feed port 4, when the metal liquid in the molding cavity 23 is cooled and the mold shrinks due to thermal expansion and contraction, the metal liquid can be continuously added to the molding cavity 23, thereby improving the internal defects of the product, making the product structure complete, and greatly reducing the scrap rate during product molding.

[0027] The runner 12 is axially parallel and arranged between the two first end walls 11 of the runner shell 1. The runner 12 extends axially upward to form a runner extension tube 13 on the top of the runner shell 1, increasing the axial height of the runner 12, so that the metal liquid in the runner 12 has a larger liquid level difference, which is convenient for replenishing the metal liquid into the molding cavity 23 through the shrinkage feeder 5 at the bottom of the runner 12 when the mold shrinks. The diameter of the runner extension tube 13 gradually increases from the runner 12 to the direction away from the runner 12, so that the runner 12 has a larger opening, which is convenient for pouring metal liquid into the runner 12, and reducing the volume of the bottom of the runner 12, reducing the metal residue in the runner 12, and reducing resource loss. Two exhaust pipes 24 are arranged along the extension direction of the runner extension pipe 13 at the top of the main shell 2. The bottom of the exhaust pipe 24 is connected to the top of the molding cavity 23. When metal liquid is added to the molding cavity 23, gas will be generated in the molding cavity 23 under the action of high temperature. After the gas is heated and expanded, it can be discharged from the exhaust pipe 24 to avoid stagnation in the molding cavity 23 to form bubbles and cause internal defects in the molded product. The exhaust pipe 24 is set at the connection between the main shell 2 and the runner shell 1. The exhaust pipe 24 is a long U-shaped open groove. The pipe walls on both sides of the runner extension pipe 13 are provided with baffles 14. The baffles 14 are connected and blocked on one side of the opening of the exhaust pipe 24 to facilitate the processing and production of the mold.

[0028] The casting mold is formed by sequentially splicing a runner shell 1 with two main shells 2 and two top shells 3 on both sides. Multiple shells are set separately, and adjacent shells are assembled by gluing and pasting, which is convenient for the processing and production of the mold. A first annular beading portion 25 arranged along the edge of the first end face 21 is provided on one side of the first end face 21 of the main shell 2, and the top shell 3 is inserted into the first beading portion 25 and connected to the first end face 21. A second annular beading portion 26 arranged along the edge of the second end face 22 is provided on one side of the second end face 22 of the main shell 2, and the first end wall 11 of the runner shell 1 is inserted into the second beading portion 26 and connected to the second end face 22. A third strip-shaped beading portion 27 is provided on one side of the exhaust pipe 24, and the two ends of the baffle 14 are clamped between the third beading portions 27 of the two exhaust pipes 24 on the main shell 2. By arranging beading clamping and covering between two adjacent shells, the structure of the mold is more compact, which can prevent the molten metal liquid in the mold from leaking out.

[0029] like Figure 6-8As shown, the runner shell 1 is composed of two oppositely arranged first half shells 6 and second half shells 7 connected together, the first half shell 6 is provided with a first half runner groove 61, the second half shell 7 is provided with a second half runner groove 71, the first half runner groove 61 and the second half runner groove 71 are assembled into a runner 12, the side wall of the first half runner groove 61 is provided with a fourth edge holding portion 62 arranged along the edge of the first half runner groove 61, the side wall of the second half runner groove 71 is inserted into the fourth edge holding portion 62 and connected to the side wall of the first half runner groove 61, further facilitating the processing and production of the mold. A cavity 15 is provided between the side wall of the runner 12 and the side wall of the runner shell 1, reducing the material consumption of the mold production and reducing the weight of the mold, and a gas port 16 connected to the cavity 15 is provided on the side wall of the runner shell 1, which can discharge the gas in the cavity 15, and avoid the mold from being broken due to the heat expansion of the gas in the cavity 15 when adding high-temperature metal liquid into the runner 12.

[0030] The above contents are merely examples and explanations of the structure of the present invention. The technicians in this technical field may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the structure of the invention or exceed the scope defined by the claims, they should all fall within the protection scope of the present invention.

Claims

1. A coated sand shell casting mold, characterized in that: include: A runner shell (1), two groups of main shells (2), and two groups of top shells (3), wherein the two groups of main shells (2) are arranged opposite to each other, the main shell (2) has a first end surface (21) and a second end surface (22), a molding cavity (23) communicating with the first end surface (21) and the second end surface (22) is provided in the main shell (2), the two groups of top shells (3) are respectively matched and connected with the first end surfaces (21) of the two groups of main shells (2) to block the molding cavity (23) from one side of the first end surface (21), the runner shell (1) is connected between the two groups of main shells (2), and the runner shell (1) is connected between the two groups of main shells (2). The two first end walls (11) of the shell (1) are respectively adapted to be connected with the second end faces (22) of the two groups of main shells (2) so as to block the molding cavity (23) from one side of the second end faces (22). The runner shell (1) has a runner (12) in it. The two first end walls (11) of the runner shell (1) are both provided with a feed port (4) so ​​as to connect the runner (12) with the molding cavities (23) of the two main shells (2). A feeding riser (5) connecting the runner (12) with the molding cavity (23) is also provided below the feed port (4).

2. The casting mold according to claim 1, characterized in that: A first annular first pressing edge portion (25) is provided on one side of the first end surface (21) of the main shell (2), and the pressing edge portion (25) is arranged along the edge of the first end surface (21); the top shell (3) is inserted into the first pressing edge portion (25) and connected to the first end surface (21); a second annular second pressing edge portion (26) is provided on one side of the second end surface (22) of the main shell (2); and the first end wall (11) of the runner shell (1) is inserted into the second pressing edge portion (26) and connected to the second end surface (22).

3. The casting mold according to claim 1, characterized in that: The runner (12) is axially arranged parallel to and between the two first end walls (11) of the runner shell (1), and the runner (12) extends axially upward to form a runner extension tube (13) at the top of the runner shell (1).

4. The casting mold according to claim 3, characterized in that: The diameter of the runner extension pipe (13) gradually increases from the runner (12) toward a direction away from the runner (12).

5. The casting mold according to claim 3, characterized in that: A cavity (15) is provided between the side wall of the runner (12) and the side wall of the runner shell (1), and an air port (16) communicating with the cavity (15) is provided on the side wall of the runner shell (1).

6. The casting mold according to claim 3, characterized in that: Two exhaust pipes (24) are arranged on the top of the main shell (2) along the extension direction of the runner extension pipe (13), and the bottom of the exhaust pipe (24) is connected to the top of the molding cavity (23).

7. The casting mold according to claim 6, characterized in that: The exhaust pipe (24) is arranged at the connection between the main shell (2) and the runner shell (1), and the exhaust pipe (24) is a long U-shaped opening groove. The pipe walls on both sides of the runner extension pipe (13) are provided with baffles (14), and the baffles (14) are connected to and block one side of the opening of the exhaust pipe (24).

8. The casting mold according to claim 7, characterized in that: A third elongated edge pressing portion (27) is provided on one side of the exhaust pipe (24), and two ends of the baffle (14) are clamped between the third edge pressing portions (27) of the two exhaust pipes (24) on the main shell (2).

9. The casting mold according to claim 1, characterized in that: The runner shell (1) is composed of two oppositely arranged first half shells (6) and second half shells (7) connected together; the first half shell (6) is provided with a first half runner groove (61); the second half shell (7) is provided with a second half runner groove (71); the side wall of the first half runner groove (61) is provided with a fourth edge holding portion (62) arranged along the edge of the first half runner groove (61); the side wall of the second half runner groove (71) is inserted into the fourth edge holding portion (62) and connected to the side wall of the first half runner groove (61).

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