A die-casting mold for automobile gearbox housing

Abstract

The utility model relates to the field of automobile parts manufacturing and discloses a die-casting mold for an automobile gearbox housing. When aluminum liquid in a mold cavity cools to form a semi-solid casting, an extrusion drive mechanism drives a pressing head to extend toward the surface of the casting through a push rod. The pressing head gradually squeezes the surface of the casting, not only gradually squeezing to form a threaded hole position, but also guiding the gas near the squeezing point to the threaded hole position, thereby reducing the generation of pores on the casting surface and improving the surface smoothness of the automobile gearbox housing.

Description

Technical Field

[0001] This utility model relates to the field of automotive parts manufacturing, and in particular to a die-casting mold for automotive transmission housings. Background Technology

[0002] The automotive transmission housing is a crucial component of the transmission. Most automotive parts have irregular shapes and are typically formed using die-casting molds. However, the complex structure and large size of the transmission housing result in long runners within the mold cavity. The high-temperature molten aluminum cools and solidifies rapidly; by the time it flows through the runner, its temperature has already dropped significantly. This means the pressure transmitted from the pressure chamber cannot be maintained until the casting has fully solidified. Furthermore, because the molten aluminum is in contact with the mold surface, the external cooling rate is faster than the internal cooling rate. The final solidification point, or hot spot, is often located internally. Porosity frequently occurs at these hot spots, often leading to shrinkage cavities and affecting product quality. See [link / reference] Figure 7 As shown, area A of the automotive gearbox housing suffers from severe porosity due to the large number of openings. Currently, to reduce porosity, an extrusion mechanism is typically used to pressurize the molten aluminum while it is in a semi-solid state, i.e., by extruding the molten aluminum through an extrusion rod. Although this reduces porosity, it also leaves extrusion marks (such as pits) on the casting. To further improve the quality of the casting, improvements are necessary. In fact, during the die casting of the automotive gearbox housing, a core-pulling shaft is needed to form the core-pulling hole. If the extrusion position can correspond to the core-pulling hole position, it will not cause new defects in the casting and can also form the corresponding hole position. Utility Model Content

[0003] In view of the shortcomings of the prior art, the purpose of this utility model is to provide a die-casting mold for automotive gearbox housing, which aims to not only reduce the generation of porosity on the casting, but also avoid the formation of new defects.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A die-casting mold for an automotive transmission housing includes a moving mold base, a fixed mold base, a moving mold core disposed on the moving mold base, a fixed mold core disposed on the fixed mold base, a first core-pulling mechanism, a second core-pulling mechanism, a third core-pulling mechanism, and a fourth core-pulling mechanism for core-pulling forming of the side portion of the automotive transmission housing. The first core-pulling mechanism includes a first core-pulling slide, a first guide slide fixed to the back of the first core-pulling slide, and a first drive mechanism for driving the first core-pulling slide and the first guide slide to move synchronously. The second core-pulling mechanism includes a second core-pulling slide, a second guide slide fixed to the back of the second core-pulling slide, and a second drive mechanism for driving the second core-pulling slide and the second guide slide to move synchronously. The third core-pulling mechanism includes a third core-pulling slide, a third guide slide fixed to the back of the third core-pulling slide, and a third drive mechanism for driving the third core-pulling slide and the third guide slide to move synchronously. The fourth core-pulling mechanism... The core-pulling mechanism includes a fourth core-pulling slide, a fourth guide slide fixed to the back of the fourth core-pulling slide, and a fourth drive mechanism for driving the fourth core-pulling slide and the fourth guide slide to move synchronously. The fixed mold core, the moving mold core, the first core-pulling slide, the second core-pulling slide, the third core-pulling slide, and the fourth core-pulling slide are combined to form a mold cavity. The casting port is set on the fixed mold core. The first core-pulling slide and the first guide slide are provided with a sleeve extending along the moving direction of the first core-pulling slide and a push rod set in the sleeve and slidable relative to the sleeve. One end of the push rod is connected to the pressure head, and the other end is connected to the extrusion drive mechanism through a transmission component. The extrusion drive mechanism drives the pressure head to extend out of the sleeve through the push rod. The pressure head is used to extrude the semi-cured casting to form a threaded hole and guide the air bubbles around the threaded hole to converge into the threaded hole. When the pressure head retracts into the sleeve, the pressure head is flush with the inner wall of the mold cavity.

[0006] As a further improvement to the above technical solution, the end of the sleeve near the pressure head is beveled, and the end of the sleeve away from the pressure head is provided with a stop positioning head.

[0007] As a further improvement to the above technical solution, the pressure head is cone-shaped.

[0008] As a further improvement to the above technical solution, the extrusion drive mechanism is a hydraulic cylinder, and the transmission component is a coupling.

[0009] As a further improvement to the above technical solution, a core-pulling track is provided through the interior of the second core-pulling slide and the second guide slide. A fifth core-pulling slide and a fifth guide slide are provided in the core-pulling track. The moving direction of the fifth core-pulling slide intersects with the moving direction of the second core-pulling slide to form an angle.

[0010] As a further improvement to the above technical solution, a vertical plate is provided on the back of the second guide slide, a guide rail is provided on the vertical plate to guide the fifth guide slide, and a fifth drive mechanism is provided on the vertical plate to drive the fifth guide slide.

[0011] Beneficial effects:

[0012] Compared with the prior art, the die-casting mold provided by this utility model is used to process and form an automotive gearbox housing. When the molten aluminum in the mold cavity cools and forms a semi-solid casting, the extrusion drive mechanism drives the pressure head to extend towards the surface of the casting through the push rod. The pressure head gradually extrudes the surface of the casting, not only gradually extruding and forming threaded holes, but also guiding the gas near the extrusion point to the threaded holes, thereby reducing the generation of air holes on the surface of the casting and improving the surface smoothness of the automotive gearbox housing. Attached Figure Description

[0013] Figure 1 A perspective view of the die-casting mold provided by this utility model.

[0014] Figure 2 This is a schematic diagram of the internal structure of the die-casting mold provided by this utility model.

[0015] Figure 3 This is a schematic diagram of the pressure head extending into the mold cavity.

[0016] Figure 4 for Figure 3 A magnified view of a portion of region L in the middle.

[0017] Figure 5 This is an assembly drawing of the pressure head, sleeve, push rod, and transmission components.

[0018] Figure 6 This is a perspective view of the second core-pulling mechanism, the fifth core-pulling slide, the fifth guide slide, and the fifth drive mechanism.

[0019] Figure 7 This is a 3D view of the car transmission housing.

[0020] Key component symbols: 61-Moving mold frame, 62-Fixed mold frame, 63-Moving mold core, 64-Fixed mold core, 65-Mold cavity, 1-First core-pulling mechanism, 11-First core-pulling slide, 12-First guide slide, 2-Second core-pulling mechanism, 21-Second core-pulling slide, 22-Second guide slide, 23-Second drive mechanism, 3-Third core-pulling mechanism, 31-Third core-pulling slide, 32-Third guide slide, 4-Fourth core-pulling mechanism, 41-Fourth core-pulling slide, 42-Fourth guide slide, 51-Vertical plate, 52-Fifth core-pulling slide, 53-Fifth guide slide, 54-Guide rail, 55-Fifth drive mechanism, 71-Sleeve, 711-Angled opening, 712-Stop positioning head, 72-Push rod, 73-Pressure head, 74-Transmission component, 8-Automotive gearbox housing, 81-Threaded hole. Detailed Implementation

[0021] This utility model provides a die-casting mold for an automotive gearbox housing 8. To make the purpose, technical solution, and effects of this utility model clearer and more explicit, the following describes this utility model in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this utility model and are not intended to limit the scope of protection of this utility model.

[0022] Please see Figures 1-7This utility model provides a die-casting mold for an automotive transmission housing 8, including a moving mold frame 61, a fixed mold frame 62, a moving mold core 63 disposed on the moving mold frame 61, a fixed mold core 64 disposed on the fixed mold frame 62, and a first core-pulling mechanism 1, a second core-pulling mechanism 2, a third core-pulling mechanism 3, and a fourth core-pulling mechanism 4 for core-pulling forming of the side of the automotive transmission housing 8. The first core-pulling mechanism 1 includes a first core-pulling slide 11 and a first guide slide 12 fixedly disposed on the back of the first core-pulling slide 11 for driving the first core-pulling slide 11 and the first guide slide 12. The first drive mechanism for synchronous movement of the guide slide 12; the second core-pulling mechanism 2 includes a second core-pulling slide 21, a second guide slide 22 fixed to the back of the second core-pulling slide 21, and a second drive mechanism 23 for driving the second core-pulling slide 21 and the second guide slide 22 to move synchronously; the third core-pulling mechanism 3 includes a third core-pulling slide 31, a third guide slide 32 fixed to the back of the third core-pulling slide 31, and a third drive mechanism for driving the third core-pulling slide 31 and the third guide slide 32 to move synchronously; the fourth core-pulling mechanism... 4 includes a fourth core-pulling slide 41, a fourth guide slide 42 fixed to the back of the fourth core-pulling slide 41, and a fourth drive mechanism for driving the fourth core-pulling slide 41 and the fourth guide slide 42 to move synchronously; the fixed mold core 64, the moving mold core 63, the first core-pulling slide 11, the second core-pulling slide 21, the third core-pulling slide 31, and the fourth core-pulling slide 41 are combined to form a mold cavity 65, the casting gate is provided on the fixed mold core 64, and the interior of the first core-pulling slide 11 and the first guide slide 12 is provided with a movable part along the first core-pulling slide 11. A sleeve 71 extending in a certain direction, and a push rod 72 disposed inside the sleeve 71 and slidable relative to the sleeve 71. One end of the push rod 72 is connected to a pressure head 73, and the other end is connected to an extrusion drive mechanism through a transmission component 74. The extrusion drive mechanism drives the pressure head 73 to extend out of the sleeve 71 through the push rod 72. The pressure head 73 is used to extrude the semi-cured casting to form a threaded hole 81 and guide the air bubbles around the threaded hole 81 to converge into the threaded hole 81. When the pressure head 73 retracts into the sleeve 71, the pressure head 73 is flush with the inner wall of the mold cavity 65.

[0023] During die casting, the fixed mold core 64 and the moving mold core 63 merge. The first drive mechanism drives the first core-pulling slide 11 and the second guide slide 22 to move towards the mold center. The second drive mechanism 23 drives the second core-pulling slide 21 and the second guide slide 22 to move towards the mold center. The third drive mechanism drives the third core-pulling slide 31 and the third guide slide 32 to move towards the mold center. The fourth drive mechanism drives the fourth core-pulling slide 41 and the fourth guide slide 42 to move towards the mold center. The fixed mold core 64, the moving mold core 63, the first core-pulling slide 11, the second core-pulling slide 21, the third core-pulling slide 31, and the fourth core-pulling slide 41 combine to form a closed mold cavity 65. At this time, when the pressure head 73 retracts the sleeve 71, the pressure head 73 is flush with the inner wall of the mold cavity 65. Then, molten aluminum is injected into the mold cavity 65 through the casting gate and gradually fills the entire cavity under pressure. It then cools to form a semi-solid casting. At this time, the extrusion drive mechanism drives the pressure head 73 to extend towards the surface of the casting through the push rod 72. The pressure head 73 gradually extrudes the surface of the casting, not only gradually forming the threaded hole 81, but also guiding the gas near the extrusion point to the threaded hole 81, thereby reducing the generation of air holes on the surface of the casting and improving the surface smoothness of the automotive gearbox housing 8. After the casting has completely cooled, the extrusion drive mechanism drives the pressure head 73 to reset and withdraw through the push rod 72. Finally, the moving mold core 63, the first core-pulling slide 11, the second core-pulling slide 21, the third core-pulling slide 31, and the fourth core-pulling slide 41 are reset, and the casting is unloaded by the robot arm.

[0024] It is important to understand that the first core-pulling slide 11, the second core-pulling slide 21, the third core-pulling slide 31, and the fourth core-pulling slide 41 are all equipped with multiple core-pulling shafts. These core-pulling shafts are used to perform core-pulling and hole-making on the automotive transmission housing 8, thereby forming holes in the automotive transmission housing 8. It is also important to understand that the threaded hole 81 does not refer to a threaded hole directly formed by the pressure head 73. The pressure head 73 only forms a blind hole, which is then tapped to form a threaded hole.

[0025] Specifically, the end of the sleeve 71 near the pressure head 73 has a bevel 711 to ensure that the sleeve 71 fits snugly against the inner wall of the mold cavity 65, thus preventing countersunk head formation in the threaded hole 81. The end of the sleeve 71 away from the pressure head 73 is provided with a stop positioning head 712. The stop positioning head 712 is used to circumferentially position the sleeve 71 and prevent it from rotating.

[0026] In this embodiment, the pressure head 73 is cone-shaped, which facilitates the application of force to penetrate the surface of the semi-solid casting, and then gradually expands the hole to form a threaded hole 81.

[0027] Preferably, the extrusion drive mechanism is a hydraulic cylinder, the transmission component 74 is a coupling, and the push rod 72 is connected to the output end of the hydraulic cylinder via the coupling. The first drive mechanism, the second drive mechanism, the third drive mechanism, and the fourth drive mechanism are all hydraulic cylinders.

[0028] Preferably, a core-pulling track is provided through the interior of the second core-pulling slide 21 and the second guide slide 22. A fifth core-pulling slide 52 and a fifth guide slide 53 are provided in the core-pulling track. The moving direction of the fifth core-pulling slide 52 intersects the moving direction of the second core-pulling slide 21 to form an angle. A vertical plate 51 is provided on the back of the second guide slide 22. A guide rail 54 is provided on the vertical plate 51 to guide the sliding of the fifth guide slide 53. A fifth driving mechanism 55 for driving the fifth guide slide 53 to slide is provided on the vertical plate 51. After the second core-pulling slide 21 moves into position, the fifth drive mechanism 55 drives the fifth core-pulling slide 52 and the fifth guide slide 53 to move towards the mold cavity 65, causing the fifth core-pulling slide 52 to extend from the inside of the second core-pulling slide 21 into the mold cavity 65. Then, molten aluminum is injected into the mold cavity 65, and the molten aluminum gradually cools and solidifies into a casting. At this time, the fifth drive mechanism 55 first drives the fifth core-pulling slide 52 to be pulled out of the mold, releasing the connection between the fifth core-pulling slide 52 and the casting. Subsequently, the second drive mechanism 23 can smoothly drive the second core-pulling slide 21 and the second guide slide 22 to move and reset, separating the second core-pulling slide 21 from the casting. The fifth core-pulling slide 52 can be used to process holes that are not in the same direction as the second core-pulling slide 21.

[0029] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0030] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection, an electrical connection, or a connection that allows for communication; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0031] It is understood that those skilled in the art can make equivalent substitutions or changes based on the technical solution and inventive concept of this utility model, and all such substitutions or changes should fall within the protection scope of this utility model.

Claims

1. A die-casting mold for an automotive transmission housing, comprising a moving mold base, a fixed mold base, a moving mold core disposed on the moving mold base, a fixed mold core disposed on the fixed mold base, a first core-pulling mechanism, a second core-pulling mechanism, a third core-pulling mechanism, and a fourth core-pulling mechanism for core-pulling forming of the side portion of the automotive transmission housing, wherein the first core-pulling mechanism includes a first core-pulling slide, a first guide slide fixedly disposed on the back of the first core-pulling slide, and a first drive mechanism for driving the first core-pulling slide and the first guide slide to move synchronously; the second core-pulling mechanism includes a second core-pulling slide, a second guide slide fixedly disposed on the back of the second core-pulling slide, and a first drive mechanism for driving the second core-pulling slide and the second guide slide to move synchronously. A second drive mechanism for synchronous movement of the guide slide; the third core-pulling mechanism includes a third core-pulling slide and a third guide slide fixed to the back of the third core-pulling slide, and a third drive mechanism for driving the third core-pulling slide and the third guide slide to move synchronously; the fourth core-pulling mechanism includes a fourth core-pulling slide and a fourth guide slide fixed to the back of the fourth core-pulling slide, and a fourth drive mechanism for driving the fourth core-pulling slide and the fourth guide slide to move synchronously; the fixed mold core, the moving mold core, the first core-pulling slide, the second core-pulling slide, the third core-pulling slide, and the fourth core-pulling slide are combined to form a mold cavity, and the fixed mold core is provided with a casting gate, characterized in that... The first core-pulling slide and the first guide slide are provided with a sleeve extending along the moving direction of the first core-pulling slide and a push rod disposed in the sleeve and slidable relative to the sleeve. One end of the push rod is connected to the pressure head, and the other end is connected to the extrusion drive mechanism through a transmission component. The extrusion drive mechanism drives the pressure head to extend out of the sleeve through the push rod. The pressure head is used to extrude the semi-cured casting to form a threaded hole and guide the air bubbles around the threaded hole to converge into the threaded hole. When the pressure head retracts into the sleeve, the pressure head is flush with the inner wall of the mold cavity.

2. The die-casting mold for an automotive gearbox housing according to claim 1, characterized in that, The end of the sleeve near the pressure head is beveled, and the end of the sleeve away from the pressure head is provided with a stop positioning head.

3. The die-casting mold for an automotive transmission housing according to claim 1, characterized in that, The pressure head is cone-shaped.

4. A die-casting mold for an automotive transmission housing according to claim 1, characterized in that, The extrusion drive mechanism is a hydraulic cylinder, and the transmission component is a coupling.

5. A die-casting mold for an automotive transmission housing according to claim 1, characterized in that, The second core-pulling slide and the second guide slide are internally connected by a core-pulling track. The core-pulling track contains a fifth core-pulling slide and a fifth guide slide. The moving direction of the fifth core-pulling slide intersects with the moving direction of the second core-pulling slide to form an angle.

6. A die-casting mold for an automotive transmission housing according to claim 5, characterized in that, The second guide slide has a vertical plate on its back, a guide rail on the vertical plate to guide the fifth guide slide, and a fifth drive mechanism on the vertical plate to drive the fifth guide slide.

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