Lost foam casting of gearbox shell

Abstract

The utility model relates to the technical field of casting molds, and discloses an evanescent mode casting of a gearbox shell, which comprises a bottom basket, a plurality of stacking baskets are sequentially stacked on the top side of the bottom basket, and a top sealing basket is arranged on the top side of the stacking basket on the topmost side. Connecting frames are fixedly connected to the side, close to the stacking basket on the topmost side, of the top sealing basket, the sides, close to the two adjacent stacking baskets, of the bottom basket and the side, close to the stacking basket on the bottommost side, of the bottom basket, and connectors are connected to the sides, close to each other, of the two adjacent connecting frames through erecting assemblies. And the bottom side of the connector is fixedly connected with an evanescent mode. According to the utility model, the evanescent mode is fixed between the connecting frames by utilizing the erecting assembly and the hourglass-shaped connector, so that the mounting stability of the evanescent mode is effectively improved, and the evanescent mode is prevented from deviating in the quartz sand filling, vibrating and air exhausting processes, thereby improving the casting precision of the gearbox shell.

Description

Technical Field

[0001] This utility model relates to the field of casting mold technology, and in particular to a lost foam casting of a gearbox housing. Background Technology

[0002] The automotive gearbox is a commonly used structure, and the automotive gearbox housing is a relatively complex casting. It is generally manufactured by lost foam casting. Lost foam mainly uses paraffin or foam models to bond and combine them into model clusters, which are then coated with refractory paint, dried, and embedded in dry quartz sand for vibration molding.

[0003] A search revealed that the lost foam casting of a light truck gearbox housing disclosed in announcement number CN206392802U includes a mold body, an ingate on the side wall of the mold body, a liquid guiding channel connected to the ingate within the side wall of the mold body, high-temperature resistant ribs adhered to the outer surface of the mold body, a coolant guiding channel within the high-temperature resistant ribs, a liquid inlet connector fixed to the top of the high-temperature resistant ribs, venting holes connected to the liquid guiding channel on the top surface of the side wall of the mold body, and a hollow slag collecting column at the top of the side wall of the mold body. This utility model has a reasonable structural design. The high-temperature resistant ribs adhered to the surface of the mold body not only prevent the mold body from tilting or deforming during vibration molding in dry quartz sand, but also effectively improve the quality of the casting. It solves the technical shortcomings of traditional lost foam casting techniques where deformation easily affects processing quality, and offers good stability and wide applicability.

[0004] The background technology mentions that after applying refractory coating and drying, the lost foam is embedded in dry quartz sand and vibrated for molding. However, the hardness of the lost foam is relatively limited, so deformation or tilting of the lost foam is prone to occur when it is embedded in dry quartz sand, which affects the casting quality, causes high waste, increases production costs, and limits its applicability and practicality. In response to this technical problem, this application proposes a lost foam casting for a gearbox housing. Utility Model Content

[0005] The purpose of this utility model is to address the shortcomings of existing technologies by proposing a lost foam casting for a gearbox housing. This invention aims to solve the problem that in existing technologies, the lost foam is prone to deformation or tilting when embedded in dry quartz sand, which affects the casting quality, causes high waste, increases production costs, and limits applicability and practicality.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A lost foam casting of a gearbox housing, comprising:

[0008] The bottom basket has multiple stacked baskets stacked sequentially on its top side. The topmost stacked basket has a top capping basket on its top side. The top capping basket and the topmost stacked basket, the adjacent sides of two adjacent stacked baskets, and the bottom basket and the bottommost stacked basket are all fixedly connected by connecting frames. The adjacent sides of two adjacent connecting frames are connected by a connecting head through a support assembly. The bottom side of the connecting head is fixedly connected to a lost foam. The bottom basket and the stacked baskets are connected internally to form a casting cavity for embedding lost foam and filling with quartz sand to cast the gearbox housing.

[0009] The exhaust pipe has two output ends, which are fixedly connected to a connecting pipe. The outer walls of two adjacent connecting frames are fitted with sealing sleeves. The connecting pipe is connected to the sealing sleeves to improve the sealing of the gaps at the joints. Combined with the exhaust step after filling with quartz sand, this ensures that a vacuum environment is generated inside the casting cavity.

[0010] Furthermore, the mounting assembly includes a connecting frame, the bottom side of which is fixedly connected to the connecting head, and fixed frames are fixedly connected to both the left and right sides of the connecting frame. Fitting grooves are opened on the adjacent sides of two adjacent connecting frames, and the front and rear ends of the fixed frames are fitted into the fitting grooves.

[0011] Furthermore, the connector is hourglass-shaped with a broken section at the middle. There are multiple connectors, which are arranged around the top side of the lost foam casting.

[0012] Furthermore, both the connector and the lost foam casting are made of paraffin wax.

[0013] Furthermore, the sealing sleeve includes a sealing frame one that is slidably connected to the outer walls of two adjacent connecting frames. One end of the sealing frame one is connected to a sealing frame two via an installation component. The sealing frame two is sleeved on the outer walls of two adjacent connecting frames. Two connecting pipes are respectively fixedly connected to the front and rear ends of the sealing frame two. An air extraction groove is provided on the inner circumference of the sealing frame one, and the connecting pipe is inserted into the opening of the air extraction groove.

[0014] Furthermore, the mounting assembly includes a connecting lug plate and a fixing bolt fixedly connected to the top side of the second sealing frame. The bottom end of the fixing bolt is threaded to the top side of the first sealing frame, the middle end of the fixing bolt is threaded to the inside of the connecting lug plate, and the top end of the fixing bolt is fixedly connected to a force-applying part.

[0015] Furthermore, an air pump for air extraction is externally connected to the input end of the air extraction pipe.

[0016] Furthermore, a sand discharge port is fixedly connected to the bottom side of the bottom basket, and a flange for connecting a valve is fixedly connected to the bottom end of the sand discharge port to discharge quartz sand.

[0017] This utility model has the following beneficial effects:

[0018] 1. In this utility model, the lost foam is fixed between the connecting frame using the mounting components and the hourglass-shaped connector, which effectively improves the installation stability of the lost foam and prevents it from shifting during the quartz sand filling, vibration and air extraction process, thereby improving the casting accuracy of the gearbox housing.

[0019] 2. This utility model significantly improves the sealing performance of the sand box joints, ensuring a stable vacuum environment is formed inside the sand box during evacuation, which is beneficial for the vaporization of lost foam casting and the flow of molten metal, thereby improving the quality and precision of the castings.

[0020] 3. In this utility model, both the connector and the lost foam are made of paraffin wax. After casting, the casting can be easily separated from the connecting frame by tapping the broken part on the connector, which simplifies the operation, avoids damage to the surface of the casting, and is beneficial to subsequent fine finishing. Attached Figure Description

[0021] Figure 1 This is a perspective view of a lost foam casting of a gearbox housing according to the present invention.

[0022] Figure 2 This is a schematic diagram of the bottom side structure of a lost foam casting of a gearbox housing according to the present invention;

[0023] Figure 3 This is a schematic diagram showing the disassembled structure of a lost foam casting of a gearbox housing according to the present invention.

[0024] Figure 4 This is a schematic diagram showing the position of the connecting bracket for a lost foam casting of a gearbox housing according to the present invention.

[0025] Figure 5 This is a schematic diagram of the connection structure of the lost foam casting of a gearbox housing according to the present invention.

[0026] Figure 6 This is a schematic diagram of the structure of the connector of the lost foam casting of the gearbox housing proposed in this utility model;

[0027] Figure 7 This is a schematic diagram of the structure of sealing frame one and sealing frame two of a lost foam casting of a gearbox housing according to the present invention.

[0028] Figure 8 This is a schematic diagram of the connecting pipe structure of a lost foam casting of a gearbox housing proposed in this utility model.

[0029] Legend:

[0030] 1. Base basket; 2. Stacking basket; 3. Top basket; 4. Connecting frame; 5. Fixing frame; 6. Connecting frame; 7. Lost foam casting; 8. Connecting head; 9. Broken part; 10. Sealing frame one; 11. Sealing frame two; 12. Connecting pipe; 13. Air extraction pipe; 14. Connecting ear plate; 15. Fixing bolt; 16. Sand discharge port. Detailed Implementation

[0031] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0032] One embodiment provided by this utility model:

[0033] A lost foam casting of a gearbox housing, comprising:

[0034] Reference Figure 1 , Figure 3 and Figure 5 The bottom basket 1 has multiple stacked baskets 2 stacked on its top side. The topmost stacked basket 2 has a top basket 3. The top basket 3 is fixedly connected to the topmost stacked basket 2 on the side closest to it, to the side closest to two adjacent stacked baskets 2, and to the bottom basket 1 on the side closest to the bottommost stacked basket 2. The side closest to two adjacent connecting frames 4 are connected to a connector 8 through a support assembly. The bottom of the connector 8 is fixedly connected to a lost foam 7. The bottom basket 1 and the stacked baskets 2 are connected internally to form a casting cavity, into which the lost foam 7 is embedded and filled with quartz sand for casting the gearbox housing.

[0035] Specifically, the shape of the lost foam 7 corresponds to the shape of the gearbox housing. This lost foam casting follows the standard lost foam casting process for casting the gearbox housing. The casting channels and gates during the casting process are designed according to the actual casting process to ensure that the cast gearbox housing meets production standards. Before casting the gearbox housing, the lost foam 7 must be prepared. The lost foam 7 is fixed to the connecting frame 6 via the connector 8. The fixing frame 5 is lifted by the machine, and the lost foam 7 and connector 8 connected to the fixing frame 5 are immersed in the paint bath. After being coated with fire-retardant paint, the lost foam 7 is dried.

[0036] Reference Figure 3 and Figure 7 and Figure 8The exhaust pipe 13 has two output ends, which are fixedly connected to connecting pipes 12. Sealing sleeves are fitted onto the outer walls of two adjacent connecting frame frames 4. The connecting pipes 12 are connected to the sealing sleeves to improve the sealing of the joints. Combined with the exhaust process after filling with quartz sand, this ensures the generation of a vacuum environment inside the casting cavity. The sealing sleeve includes a sealing frame 10 that is slidably connected to the outer walls of two adjacent connecting frame frames 4. One end of the sealing frame 10 is connected to a sealing frame 11 via an installation component. The sealing frame 11 is fitted onto the outer walls of the two adjacent connecting frames. On the outer wall of frame 4, two connecting pipes 12 are fixedly connected to the front and rear ends of sealing frame 2 11 respectively. A suction groove is opened on the inner circumference of sealing frame 10. The connecting pipe 12 is inserted into the opening of the suction groove. The installation assembly includes a connecting ear plate 14 and a fixing bolt 15 fixedly connected to the top side of sealing frame 2 11. The bottom end of the fixing bolt 15 is threaded to the top side of sealing frame 10, the middle end of the fixing bolt 15 is threaded to the inside of the connecting ear plate 14, and the top end of the fixing bolt 15 is fixedly connected to a force-applying part. The input end of the suction pipe 13 is externally connected to a suction pump for suction.

[0037] Specifically, the sealing frame 10 is slidably fitted onto two adjacent connecting frame 4, and the sealing frame 2 11 is inserted into the opening of the sealing frame 10. The connecting pipe 12 is inserted into the venting groove. The fixing bolt 15 is aligned with the screw grooves opened on the top side of the connecting ear plate 14 and the sealing frame 10, and the fixing bolt 15 is tightened in the overlapping slots. The installation of the sealing frame 10 and the sealing frame 2 11 is then completed. The casting channel and casting port are arranged in the casting cavity, and quartz sand is laid on top. After compaction by vibration, A thin film is laid on the top side of the capping basket 3, leaving a casting port, covering the quartz sand on the top side, and a vacuum pipe is connected. The vacuum pump is started, and the vacuum pump is used to simultaneously evacuate the pipe and the vacuum pipe 13, so that the air inside the quartz sand is extracted. The air in the gap at the connection of the two adjacent connecting frames 4 enters the connecting pipe 12 through the vacuum groove, and then enters the vacuum pipe 13 through the connecting pipe 12 and is extracted by the vacuum pump, so that the air in the quartz sand is fully extracted. Then the molten metal is poured through the casting port.

[0038] Reference Figures 4-6The mounting components include a connecting frame 6, with its bottom side fixedly connected to a connecting head 8. Fixing frames 5 are fixedly connected to both sides of the connecting frame 6. Both the connecting frame 6 and the fixing frames 5 are made of metal unaffected by high-temperature molten metal. Adjacent sides of two adjacent connecting frame frames 4 have fitting grooves, with both ends of the fixing frames 5 fitting into these grooves. The fitting of adjacent grooves with the fixing frames 5 serves a positioning and installation function. The connecting head 8 is hourglass-shaped with a broken section 9 in the middle. Multiple connecting heads 8 are arranged around the top side of the lost foam 7, using this surrounding structure to stabilize the connection between the lost foam 7 and the connecting frame 6. Both the connecting head 8 and the lost foam 7 are made of paraffin wax. After casting, the lost foam 7 is cast together with the connecting head 8, ensuring that the gearbox housing remains adhered to the connecting frame 6 when the finished gearbox housing is removed. Please refer to [reference needed]. Figure 4 The number of connecting frames 6 in the figure is multiple, and there are multiple lost foam 7 fixed to them. This allows multiple gearbox housings to be removed at the same time after casting is completed by removing the fixing frame 5. Before casting, multiple lost foam 7 can be immersed in the coating pool by moving the fixing frame 5 to add refractory coating, which greatly increases the work efficiency. Furthermore, through this fixing structure, the movement of quartz sand will not cause the lost foam 7 to shift when filling quartz sand, vibrating quartz sand, and evacuating air from the quartz sand, thereby improving the casting accuracy.

[0039] Specifically, the fixing bracket 5 is installed by aligning it with the fitting groove on the connecting frame 4. After one layer is installed, a stacking basket 2 is placed on top, and the above installation process is repeated until the top stacking basket 2 fills the fixing bracket 5. Finally, the top sealing basket 3 is placed on top to complete the placement of the lost foam 7. After removing the multiple gearbox housings that are adhered to the connecting bracket 6, the broken part 9 on the connector 8 is tapped. The structure of the broken part 9 and the hourglass-shaped connector 8 have a certain force angle, allowing the connector 8 to be stressed at the broken part 9 and break, thereby removing the gearbox housing and sending it to the surface finishing step of the gearbox housing to repair the surface of the gearbox housing and the remaining connector 8.

[0040] Reference Figure 2 The bottom side of the bottom basket 1 is fixedly connected to a sand discharge port 16, and the bottom end of the sand discharge port 16 is fixedly connected to a flange for connecting a valve to discharge quartz sand.

[0041] Working principle: When casting the gearbox housing, the lost foam 7 is first prepared and fixed to the connecting frame 6 via the connector 8. The fixing frame 5 is lifted by the machine, and the lost foam 7 and connector 8 connected to the fixing frame 5 are immersed in the paint bath and coated with fire-retardant paint. The lost foam 7 is then dried. After drying, the fixing frame 5 is aligned with the fitting groove on the connecting frame 4 and installed. After one layer is installed, a stacking basket 2 is placed on top, and the above installation process is repeated until the top stacking basket 2 is completed. After placing the fixing frame 5, finally cover it with the top cover basket 3 to complete the placement of the lost foam 7. At this time, slide the sealing frame 10 onto the two adjacent connecting frame 4, and insert the sealing frame 2 11 into the opening of the sealing frame 10. Insert the connecting pipe 12 into the venting groove, align the fixing bolt 15 with the threaded groove opened on the top side of the connecting ear plate 14 and the sealing frame 10, and tighten the fixing bolt 15 in the overlapping hole groove. Then the installation of the sealing frame 10 and the sealing frame 2 11 is completed. Arrange the casting channel and casting port into the casting cavity. The quartz sand is then spread and compacted by vibration. A thin film is laid on the top side of the capping basket 3, leaving a pouring opening. The quartz sand on the top side is covered, and an air extraction pipe is connected. The air extraction machine is started, and it simultaneously extracts air from the pipe and the extraction pipe 13, causing the air inside the quartz sand to be extracted. Air from the gaps at the joints of two adjacent connecting frames 4 enters the connecting pipe 12 through the air extraction groove, and then enters the extraction pipe 13 through the connecting pipe 12, where it is extracted by the air extraction machine. This ensures that the air in the quartz sand is fully extracted. Then, the molten metal is poured along the pouring... The casting is carried out through the casting channel and poured into the lost foam 7. After casting is completed, the quartz sand is discharged through the sand discharge port 16. The sealing frame 10, sealing frame 21, top basket 3 and stacking basket 2 are removed. The multiple gearbox housings that are stuck to the connecting frame 6 are taken out. The broken part 9 on the connector 8 is knocked to break the connector 8 at the broken part 9, so that the gearbox housing can be removed and sent to the surface finishing step of the gearbox housing to repair the surface of the gearbox housing and the remaining connector 8.

[0042] Finally, it should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present 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 the present utility model should be included within the protection scope of the present utility model.

Claims

1. A lost foam casting for a gearbox housing, characterized in that, include: The bottom basket (1) has multiple stacked baskets (2) stacked sequentially on its top side. The topmost stacked basket (2) has a top basket (3) fixedly connected to the topmost stacked basket (2) on its side, the adjacent stacked baskets (2) on their side, and the bottom basket (1) and the bottommost stacked basket (2) on their side. The adjacent connecting frames (4) are connected to the adjacent connecting frames (4) by a support assembly. The bottom of the connecting frame (8) is fixedly connected to a lost foam (7). The bottom basket (1) and the stacked baskets (2) are connected internally to form a casting cavity, into which the lost foam (7) is embedded and quartz sand is filled for casting the gearbox housing. The exhaust pipe (13) has two output ends and is fixedly connected to a connecting pipe (12). The outer walls of the two adjacent connecting frames (4) are fitted with sealing sleeves. The connecting pipe (12) is connected to the sealing sleeves to improve the sealing of the gap at the joint. In conjunction with the exhaust step after filling with quartz sand, the vacuum environment inside the casting cavity is guaranteed to be generated.

2. The lost foam casting of a gearbox housing according to claim 1, characterized in that: The mounting assembly includes a connecting frame (6), the bottom side of which is fixedly connected to the connecting head (8), and a fixing frame (5) is fixedly connected to both the left and right sides of the connecting frame (6). A fitting groove is provided on the adjacent side of two adjacent connecting frames (4), and the front and rear ends of the fixing frame (5) are fitted into the fitting groove.

3. The lost foam casting of a gearbox housing according to claim 1, characterized in that: The connector (8) is hourglass-shaped and has a broken part (9) in the middle. There are multiple connectors (8) and they are arranged around the top side of the lost foam (7).

4. The lost foam casting of a gearbox housing according to claim 1, characterized in that: Both the connector (8) and the lost foam (7) are made of paraffin wax.

5. The lost foam casting of a gearbox housing according to claim 1, characterized in that: The sealing sleeve includes a sealing frame one (10) that is slidably connected to the outer walls of two adjacent connecting frames (4). One end of the sealing frame one (10) is connected to a sealing frame two (11) through an installation component. The sealing frame two (11) is fitted onto the outer walls of two adjacent connecting frames (4). Two connecting pipes (12) are fixedly connected to the front and rear ends of the sealing frame two (11). An air extraction groove is provided on the inner circumference of the sealing frame one (10). The connecting pipe (12) is inserted into the opening of the air extraction groove.

6. The lost foam casting of a gearbox housing according to claim 5, characterized in that: The installation assembly includes a connecting ear plate (14) and a fixing bolt (15) fixedly connected to the top side of the second sealing frame (11). The bottom end of the fixing bolt (15) is threaded to the top side of the first sealing frame (10), the middle end of the fixing bolt (15) is threaded to the inside of the connecting ear plate (14), and the top end of the fixing bolt (15) is fixedly connected to a force-applying part.

7. The lost foam casting of a gearbox housing according to claim 1, characterized in that: The input end of the extraction pipe (13) is connected to an external air pump for extraction.

8. The lost foam casting of a gearbox housing according to claim 1, characterized in that: The bottom side of the bottom basket (1) is fixedly connected to a sand discharge port (16), and the bottom end of the sand discharge port (16) is fixedly connected to a flange for connecting a valve to discharge quartz sand.

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