Low-pressure casting mold with air extractor

Abstract

The utility model discloses a low-pressure casting mould with an air extractor, which comprises an upper mould and a lower mould which are connected up and down, sand cores arranged in the upper mould and the lower mould, a core column, a copper pipe, a vacuum generator and an air plug, the core column is fixedly connected in the upper mould, a plurality of through holes penetrating up and down are arranged on the core column, and the air plug is arranged in the through holes. The air plug is embedded in the lower end of the through hole, a plurality of vertical through longitudinal grooves are evenly formed in the side face of the air plug, one end of the copper pipe is connected to the upper end of the through hole, the other end of the copper pipe is connected with the vacuum generator through an air pipe, and when the vacuum generator is started, air in the mold is exhausted out of the mold along the air plug, the through hole, the copper pipe, the air pipe and the vacuum generator. The air extractor is additionally arranged in the upper mold, so that gas generated due to gas generation of the sand core in the cavity can be actively and quickly exhausted, and the defects of air suffocation, insufficient casting and the like of a casting are reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of low-pressure casting, in particular to a low-pressure casting mold with an air extraction device. Background Art

[0002] Generally, low-pressure casting molds are vented during the casting process through air plugs, ejector structures, or parting surfaces. However, for more complex compression shells, such as those with water channels, or compression shells that cannot be directly parted from the upper and lower molds, sand cores or core pulling are required during the casting process to assist in forming.

[0003] In the prior art, for this type of compression shell casting that uses a large number of sand cores during the casting process, since the sand cores generate a large amount of gas during the compression shell casting process, it is difficult to completely discharge the gas generated by the sand cores by simply relying on the gas plug, push rod, and parting surface structure to exhaust gas, resulting in defects such as air holding and insufficient pouring during the aluminum liquid filling process, and the defect ratio is about 30%. Utility Model Content

[0004] The utility model aims to provide a low-pressure casting mold with an exhaust device to address the defects of the prior art.

[0005] In order to solve the above technical problems, the utility model provides the following technical solutions:

[0006] A low-pressure casting mold with an exhaust device, comprising an upper mold and a lower mold connected to each other, and sand cores arranged in the upper mold and the lower mold, characterized in that it also includes a core column, a copper tube, a vacuum generator, and an air plug, the core column is fixedly connected to the upper mold, a plurality of through holes penetrating from top to bottom are arranged on the core column, the air plug is embedded in the lower end of the through hole, a plurality of longitudinal grooves penetrating from top to bottom are evenly arranged on the side of the air plug, one end of the copper tube is connected to the upper end of the through hole, and the other end is connected to the vacuum generator through an air pipe, and when the vacuum generator is started, the gas in the mold is discharged from the mold along the air plug, the through hole, the copper tube, the air pipe, and the vacuum generator.

[0007] Furthermore, the vacuum generator is provided with a compressed air inlet, a suction port and an exhaust port, the compressed air inlet is connected to an external compressed air source, the suction port is connected to the air pipe, and the exhaust port is connected to a muffler.

[0008] Furthermore, a limiting protrusion is provided on the inner wall of the through hole, and a limiting groove is provided on the side of the air plug. The limiting protrusion is snapped into the limiting groove to limit the axial movement of the air plug.

[0009] Furthermore, there are four through holes evenly distributed in the core column, and the top of each through hole is connected to a group of copper tubes, air pipes and vacuum generators.

[0010] Furthermore, an interference fit is adopted between the gas plug and the through hole in the core column.

[0011] Compared with the prior art, the beneficial effects of the utility model are:

[0012] 1. Add an exhaust device in the upper mold to ensure that the gas generated by the sand core in the cavity can be actively and quickly discharged, reducing the occurrence of defects such as air holding and insufficient pouring of castings.

[0013] 2. Adding a muffler to the exhaust device can effectively reduce noise and protect the health of the operator.

[0014] 3. An interference fit is adopted between the gas plug and the core column through hole to prevent the gas plug from falling off when the vacuum device is working; a limit groove and a limit convex block are adopted between the gas plug and the through hole to prevent the gas plug from moving due to excessive suction during vacuuming, thereby preventing aluminum liquid from leaking and causing the risk of product scrapping. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a schematic diagram of the structure of an embodiment of the utility model;

[0016] Figure 2 A side sectional view of a mold of an embodiment;

[0017] Figure 3 A schematic diagram of the bottom surface of the core column of an embodiment;

[0018] Figure 4 A schematic diagram of the gas plug structure of an embodiment;

[0019] Among them: 1-upper die, 2-lower die, 3-sand core, 4-core column, 5-copper tube, 6-vacuum generator, 7-air plug, 8-through hole, 9-air pipe, 10-muffler, 11-limiting protrusion, 12-casting, 761-compressed air inlet, 62-intake port, 63-exhaust port, 71-longitudinal groove, 72-limiting groove. DETAILED DESCRIPTION

[0020] In order to deepen the understanding of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings. This embodiment is only used to explain the present invention and does not constitute a limitation on the protection scope of the present invention.

[0021] In the description of the present invention, it should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0022] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix", "set" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0023] Figure 1-4 A specific embodiment of a low-pressure casting mold with an exhaust device is shown, which includes an upper mold 1 and a lower mold 2 connected to each other, and an exhaust device arranged on the upper mold 1.

[0024] like Figure 1 As shown, the vacuum device includes a core column 4, a copper tube 5, an air pipe 9, a vacuum generator 6, an air plug 7, and a muffler 10. The core column 4 is fixedly connected to the upper mold 1. The vacuum generator 6 is provided with a compressed air inlet 61, a suction port 62 and an exhaust port 63. The compressed air inlet 61 is connected to an external compressed air source, the suction port 62 is connected to the core column 4 through the air pipe 9 and the copper tube 5 in sequence, and the exhaust port 63 is connected to the muffler 10.

[0025] like Figure 2 As shown, four groups of through holes 8 are provided in the core column 4, the air plug 7 is embedded in the lower end of the through hole 8, the copper tube 5 is connected to the upper end of the through hole 8, and the casting 12 and the sand core 3 are located in the cavity below the core column 4.

[0026] like Figure 3 , 4 As shown, the side of the gas plug 7 is evenly provided with a plurality of vertical grooves 71 that only allow gas to pass through and two symmetrical limit grooves 72, and a limit protrusion 11 is provided on the inner wall of the through hole 8. When the gas plug 7 is installed in place, the limit protrusion 11 is snapped into the limit groove 72.

[0027] Preferably, in order to prevent the air plug 7 from falling off when the air extraction device is working, a specially made air plug 7 is used, and an interference fit is adopted between the air plug 7 and the through hole 8 in the stem 4.

[0028] The working process and principle of the above embodiment are as follows:

[0029] After the upper mold 1 and the lower mold 2 of the mold are closed, the external compressed air source is turned on, and the vacuum generator 6 starts to work, and the gas generated by the sand core 3 in the mold cavity passes through the longitudinal groove 71 on the air plug 7, the copper tube 5, the air pipe 9, the vacuum generator 6 in sequence, and is finally discharged from the muffler 10 mixed with the compressed air.

[0030] In order to prevent the aluminum liquid in the cavity from being sucked up and blocking the air plug 7 during the operation of the vacuum generator 6, the opening time of the external compressed air is controlled in the first and second stages of aluminum liquid filling (i.e. 0-10s).

[0031] In addition, a limiting groove 72 and a limiting protrusion 11 are used between the air plug 7 and the through hole 8 to prevent the air plug 7 from moving due to excessive suction during vacuuming, thereby preventing aluminum liquid from leaking and causing the risk of product scrapping.

[0032] The above specific implementation methods are only for illustrating the technical concept and structural features of the utility model, and the purpose is to enable relevant persons familiar with this technology to implement them accordingly. However, the above content does not limit the protection scope of the utility model. Any equivalent changes or modifications made based on the spirit of the utility model should fall within the protection scope of the utility model.

Claims

1. A low-pressure casting mold with an exhaust device, comprising an upper mold (1) and a lower mold (2) connected to each other, and a sand core (3) arranged in the upper mold (1) and the lower mold (2), characterized in that: It also includes a core column (4), a copper tube (5), a vacuum generator (6), and an air plug (7). The core column (4) is fixedly connected to the upper mold (1). The core column (4) is provided with a plurality of through holes (8) extending vertically therethrough. The air plug (7) is embedded in the lower end of the through hole (8). The side surface of the air plug (7) is evenly provided with a plurality of vertical grooves (71) extending vertically therethrough. One end of the copper tube (5) is connected to the upper end of the through hole (8), and the other end is connected to the vacuum generator (6) through an air pipe (9). When the vacuum generator (6) is started, the gas in the mold is discharged from the mold along the air plug (7), the through hole (8), the copper tube (5), the air pipe (9), and the vacuum generator (6).

2. A low-pressure casting mold with an exhaust device according to claim 1, characterized in that: The vacuum generator (6) is provided with a compressed air inlet (61), a suction port (62) and an exhaust port (63); the compressed air inlet (61) is connected to an external compressed air source, the suction port (62) is connected to the air pipe (9), and the exhaust port (63) is connected to a muffler (10).

3. The low-pressure casting mold with an exhaust device according to claim 1, characterized in that: A limiting protrusion (11) is provided on the inner wall of the through hole (8), a limiting groove (72) is provided on the side of the air plug (7), and the limiting protrusion (11) is snap-fitted into the limiting groove (72) to limit the axial movement of the air plug (7).

4. The low-pressure casting mold with an exhaust device according to claim 1, characterized in that: The through holes (8) are provided in four numbers and are evenly distributed in the core column (4). The top of each through hole (8) is connected to a group of copper tubes (5), an air pipe (9) and a vacuum generator (6).

5. The low-pressure casting mold with an exhaust device according to claim 1, characterized in that: An interference fit is adopted between the air plug (7) and the through hole (8) in the core column (4).

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