A casting mold for improving shrinkage cavities and porosity in castings

Abstract

This utility model relates to the field of mold processing, and more particularly to a casting mold for improving shrinkage cavities and porosity in castings. It includes a lower mold, an upper mold, a heating groove, and an arc-shaped groove. The lower mold has a cavity at its upper end, and the upper mold is located above the cavity. The heating groove is fixed in the middle of the upper end of the upper mold, and a heating section with a through hole is located inside the upper mold. The bottom of the upper mold has an arc-shaped groove, the upper part of which communicates with the through hole. An air hole is located on one side of the through hole. The arc-shaped groove has a conical design. This device utilizes the heating groove with a heating effect in conjunction with the conical arc-shaped groove to achieve a material distribution effect after mold closing, solving the problem of shrinkage and depression of the molded material that easily occurs after mold closing in existing molds, which affects the overall mold processing effect.

Description

Technical Field

[0001] This utility model relates to the field of mold processing, and in particular to a casting mold for improving shrinkage cavities and porosity in castings. Background Technology

[0002] Shrinkage cavities and porosity in castings are essentially caused by insufficient compensation for liquid shrinkage and solidification shrinkage. Several key factors come to mind: feeding system design (risers and chills), alloy properties (shrinkage rate), temperature control (pouring temperature and mold temperature), pressure conditions (pressure feeding), and melting quality (gas content). Improving the problem of shrinkage cavities and porosity in castings is a systematic project that requires addressing multiple aspects, including alloy properties, process design, and process control. These defects are essentially caused by insufficient compensation for liquid shrinkage and solidification shrinkage during the metal's solidification process.

[0003] A search revealed patent publication number CN212528834U, which discloses a mold that is easy to fix, belonging to the field of mold equipment technology. The key technical points include a mold with a concave groove on its upper surface, a storage box installed on one side of the mold, a sealing door installed on one side of the storage box, a handle groove on one side of the sealing door, two C-shaped limiting rods on the front face of the mold, strip-shaped limiting posts installed on the inner side of the C-shaped limiting rods, a limiting pad installed on the upper surface of the strip-shaped limiting post, a handle installed on the lower surface of the strip-shaped limiting post, movable frames installed on both sides of the strip-shaped limiting post, a first spring installed on the lower surface of the movable frame, a movable groove provided on the outer side of the first spring, and limiting slots provided on both sides of the C-shaped limiting rods. This device has a simple structure, is easy to operate and use, has extremely high stability, and has a storage function.

[0004] While existing technologies can achieve certain mold processing effects, they also have drawbacks: the molded material is prone to shrinkage and depression after mold closing, which affects the overall mold processing effect. In view of this, we propose a casting mold that improves shrinkage cavities and porosity in castings, thus solving the above problems. Utility Model Content

[0005] The purpose of this invention is to address the problems existing in the background technology by proposing a casting mold that improves the shrinkage cavity and porosity of castings.

[0006] The technical solution of this utility model is as follows: A casting mold for improving shrinkage cavities and porosity in castings includes a lower mold, an upper mold, a heating groove, and an arc-shaped groove. The upper end of the lower mold is provided with a cavity, and the upper mold is provided above the cavity. The heating groove is fixed in the middle of the upper end of the upper mold. The upper mold is provided with a heating section inside, and a through hole is provided inside the heating section. The bottom of the upper mold is provided with an arc-shaped groove, and the upper part of the arc-shaped groove communicates with the through hole. A vent is provided on one side of the through hole. The arc-shaped groove is designed in a conical shape.

[0007] When using this device, after the upper and lower molds are closed, hot material is filled through the corresponding upper or lower feed port. After being filled into the mold, it begins to cool. Due to the effect of thermal expansion and contraction, the volume of the initially quantitatively filled material will shrink, resulting in gaps at the top of the cavity. To ensure that the mold is filled, material can be filled into the cavity through the feeding port. The filled material will be kept at a certain temperature under the action of the heating section. Excess gas in the space will be discharged through the air hole. Then, the material is repeatedly added until no gas is discharged from the air valve. After standing for a period of time, the mold is opened. After the mold is opened, there will be a protruding position at the top of the molded object, which is caused by the arc groove. It can be directly ground off. This device can use the arc groove to improve the shrinkage and porosity of the mold during molding, reduce the shrinkage problem after the mold is formed, and has high practicality.

[0008] Preferably, the upper mold is provided with limit keys at the four corners of its lower end, and the lower mold is provided with limit holes at the four corners of its upper end. The limit keys are aligned with the limit holes to prevent misalignment between the upper and lower molds through mechanical limiting.

[0009] Preferably, an air valve is provided on one side of the heating tank, the air valve is connected to an air hole, and a feeding port is provided in the middle of the upper end of the heating tank. The air valve actively regulates the gas discharge to avoid excessive air pressure from hindering the feeding process.

[0010] Preferably, a heater is fixed to the upper end of the upper mold, and the heater is electrically connected to the heating section. A temperature sensor is embedded in one side of the heating tank, and the temperature sensor is in close contact with the heating section. The heater and the temperature sensor are linked to ensure that the temperature of the heating section is stable, avoid overheating or premature solidification, and heat as needed to reduce energy waste. Both the heating section and the heating tank are provided with heat by the heater. The area where the material is located inside the heating tank can be heated and kept warm, waiting to provide material for the heating section.

[0011] Preferably, the upper mold has an upper feed port on one side of its outer wall, and an upper discharge port on one side of the upper feed port, to accommodate the filling requirements of materials with different viscosities.

[0012] Preferably, the lower mold has a lower feed port on one side of its outer wall, and a lower discharge port on one side of the lower feed port, which is suitable for bottom feeding or segmented filling of complex structures.

[0013] Preferably, the lower end of the lower mold is fixed with a base, and the bottom of the base is provided with multiple positioning holes. The base enhances the overall rigidity of the mold and prevents vibration or deformation. The positioning holes enable precise alignment with the equipment and improve production efficiency.

[0014] Compared with existing technologies, the advantages of this utility model are:

[0015] I. This utility model and device utilize the upper and lower molds to provide a precise molding space, ensuring uniform material filling and reducing molding defects. The heating tank and heating section work together to maintain the material temperature, delay local solidification, promote shrinkage flow, and reduce shrinkage cavities and porosity. In addition, the conical design of the arc groove concentrates the shrinkage allowance to easily handle the protruding parts (which can be polished later), avoiding shrinkage cavities from being scattered in key areas.

[0016] II. Based on the first beneficial effect, this solution systematically solves the shrinkage and porosity problems during the molding process through multi-stage shrinkage compensation design (heating section + arc groove + dynamic feeding), precise temperature control (heater + sensor), and modular structure (limiting key, bidirectional feeding port, etc.). Its core advantages are: active shrinkage compensation (using the arc groove to concentrate the shrinkage allowance, combined with dynamic filling through the feeding port, to ensure complete cavity compaction); wide process adaptability (the bidirectional feeding port and controllable heating meet the molding requirements of different materials (such as plastics and metal alloys); high precision and stability (the limiting structure and temperature monitoring reduce human error and improve yield); and significantly reduce subsequent processing costs, making it suitable for high-precision castings or injection molding applications.

[0017] Of course, any product implementing this utility model does not necessarily need to achieve all of the advantages described above at the same time. Attached Figure Description

[0018] Figure 1 This is a three-dimensional schematic diagram of the present invention;

[0019] Figure 2 This is an exploded view of the present invention;

[0020] Figure 3 This is a bottom view of the upper mold of this utility model;

[0021] Figure 4 This is a schematic diagram of the upper mold of this utility model.

[0022] Figure label:

[0023] 1. Base; 2. Lower mold; 3. Upper feed port; 4. Heater; 5. Feed port; 6. Heating tank; 7. Upper mold; 8. Upper discharge port; 9. Lower feed port; 10. Lower discharge port; 11. Limiting hole; 12. Cavity; 13. Limiting key; 14. Air valve; 15. Temperature sensor; 16. Arc groove; 17. Through hole; 18. Air hole; 19. Heating section. Detailed Implementation

[0024] To make the above-mentioned objectives, features and advantages of this utility model more readily understood, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings.

[0025] Many specific details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0026] Secondly, this utility model is described in detail with reference to the schematic diagrams. When describing the embodiments of this utility model, for ease of explanation, the cross-sectional views illustrating the device structure may be partially enlarged, not adhering to the usual scale. Furthermore, the schematic diagrams are merely examples and should not limit the scope of protection of this utility model. In addition, actual manufacturing should include the three-dimensional spatial dimensions of length, width, and depth.

[0027] To make the objectives, technical solutions, and advantages of this utility model clearer, the embodiments of this utility model will be described in further detail below with reference to the accompanying drawings.

[0028] Example 1

[0029] Please see Figures 1-4 As shown, this embodiment is a casting mold for improving shrinkage cavities and porosity in castings, including a lower mold 2, an upper mold 7, a heating groove 6, and an arc-shaped groove 16. The lower mold 2 has a cavity 12 at its upper end, and the upper mold 7 is located above the cavity 12. The heating groove 6 is fixed in the middle of the upper end of the upper mold 7. The upper mold 7 has a heating section 19 inside, and a through hole 17 inside the heating section 19. The bottom of the upper mold 7 has an arc-shaped groove 16. The upper part of the arc-shaped groove 16 communicates with the through hole 17. A vent 18 is provided on one side of the through hole 17. The arc-shaped groove 16 has a conical design.

[0030] When using this device, after the upper mold 7 and lower mold 2 are closed, hot material is filled from the corresponding upper feed port 3 or lower feed port 9. After filling into the mold, it begins to cool. Due to the effect of thermal expansion and contraction, the volume of the initially quantitatively filled material will shrink, resulting in a gap at the upper end of the cavity 12. In order to ensure that the mold is filled, the material can be filled into the cavity 12 through the material feeding port. The filled material will be filled at a certain temperature under the action of the heating section 19. The gas in the excess space is discharged from the air hole 18. Then, the material is repeatedly added until no gas is discharged from the air valve 14. After standing for a period of time, the mold is opened. After the mold is opened, there is a protruding position at the upper end of the molded object, which is generated by the arc groove 16. It can be directly ground off. This device can use the arc groove 16 to improve the shrinkage and porosity of the mold during molding, reduce the shrinkage problem after the mold is formed, and has high practicality.

[0031] Limiting keys 13 are provided at the four corners of the lower end of the upper mold 7, and limiting holes 11 are provided at the four corners of the upper end of the lower mold 2. The limiting keys 13 and the limiting holes 11 are aligned. The mechanical limiting prevents the upper mold 7 and the lower mold 2 from being misaligned, ensuring the accuracy of the forming dimensions and reducing problems such as flash or uneven wall thickness.

[0032] Example 2

[0033] Please see Figures 1-4 As shown, this embodiment further includes, based on embodiment 1, a gas valve 14 on one side of the heating tank 6, the gas valve 14 being connected to the gas hole 18, a feeding port 5 in the middle of the upper end of the heating tank 6, the gas valve 14 actively regulating the gas discharge to avoid excessive gas pressure hindering the shrinkage, and the feeding port 5 can inject high-temperature materials multiple times during the cooling stage to continuously compensate for the shrinkage volume.

[0034] A heater 4 is fixed to the upper end of the upper mold 7. The heater 4 is electrically connected to the heating section 19. A temperature sensor 15 is embedded in one side of the heating tank 6. The temperature sensor 15 is in close contact with the heating section 19. The heater 4 and the temperature sensor 15 are linked to ensure that the temperature of the heating section 19 is stable, avoiding overheating or premature solidification, and heating on demand to reduce energy waste. Both the heating section 19 and the heating tank 6 are provided with heat by the heater 4. The area where the material is located inside the heating tank 6 can be heated and kept warm, waiting to provide material for the heating section 19. The volume of the heating section 19 is relatively small. Under the condition of relatively equal heating effect, the temperature can be slightly increased to replenish the material.

[0035] The upper mold 7 has an upper feed port 3 on one side of its outer wall, and an upper discharge port 8 on one side of the upper feed port 3. This adapts to the filling requirements of materials with different viscosities, and is especially suitable for top shrinkage processes. The discharge port can discharge excess material and reduce waste.

[0036] The lower mold 2 has a lower feed port 9 on one side of its outer wall, and a lower discharge port 10 on one side of the lower feed port 9. This is suitable for bottom feeding or segmented filling of complex structures, improving adaptability and supporting various processes such as gravity casting and pressure-assisted casting.

[0037] The lower mold 2 is fixed with a base 1 at its lower end. The base 1 has multiple positioning holes at its bottom. The base 1 enhances the overall rigidity of the mold and prevents vibration or deformation. The positioning holes enable precise alignment with the equipment and improve production efficiency.

[0038] Finally, it should be noted that the above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A casting mold for improving shrinkage cavities and porosity in castings, comprising a lower mold (2), an upper mold (7), a heating groove (6), and an arc-shaped groove (16), characterized in that: The lower mold (2) has a cavity (12) at its upper end, and an upper mold (7) is provided above the cavity (12). A heating groove (6) is fixed in the middle of the upper end of the upper mold (7). A heating section (19) is provided inside the upper mold (7). A through hole (17) is provided inside the heating section (19). An arc groove (16) is provided at the bottom of the upper mold (7). The upper part of the arc groove (16) is connected to the through hole (17). An air hole (18) is provided on one side of the through hole (17). The arc groove (16) is tapered.

2. The casting mold for improving shrinkage cavities and porosity in castings according to claim 1, characterized in that: The upper mold (7) is provided with limit keys (13) at the four corners of its lower end, and the lower mold (2) is provided with limit holes (11) at the four corners of its upper end. The limit keys (13) are aligned with the limit holes (11).

3. A casting mold for improving shrinkage cavities and porosity in castings according to claim 1, characterized in that: A gas valve (14) is provided on one side of the heating tank (6), and the gas valve (14) is connected to the air hole (18). A feeding port (5) is provided in the middle of the upper end of the heating tank (6).

4. A casting mold for improving shrinkage cavities and porosity in castings according to claim 1, characterized in that: A heater (4) is fixed at the upper end of the upper mold (7). The heater (4) is electrically connected to the heating section (19). A temperature sensor (15) is embedded in one side of the heating groove (6). The temperature sensor (15) is in contact with the heating section (19).

5. A casting mold for improving shrinkage cavities and porosity in castings according to claim 1, characterized in that: The upper mold (7) has an upper feed port (3) on one side of its outer wall, and an upper discharge port (8) is provided on one side of the upper feed port (3).

6. A casting mold for improving shrinkage cavities and porosity in castings according to claim 1, characterized in that: The lower mold (2) has a lower feed port (9) on one side of its outer wall, and a lower discharge port (10) is provided on one side of the lower feed port (9).

7. A casting mold for improving shrinkage cavities and porosity in castings according to claim 1, characterized in that: The lower mold (2) is fixed with a base (1) at its lower end, and the base (1) has multiple positioning holes at its bottom.

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