Differential shell forming mold assembly

Abstract

The utility model relates to the technical field of differential shell casting production, in particular to a differential shell forming mold assembly which comprises a differential shell mold, an insertion core, a differential compensation structure and a pouring channel. The insertion core is embedded in the middle of the differential shell cavity; the insertion core is internally provided with an installation space and a communication space which take steps as boundaries and are communicated up and down, and the communication space is communicated with the differential shell cavity. The bottom of the difference compensation structure is embedded in the installation space, the peripheral surface of the difference compensation structure is attached to the inner side wall of the insertion core, and the difference compensation structure protrudes out of the insertion core upwards. The interior of the difference compensation structure is hollow to form a containing space, the top of the difference compensation structure is closed, the bottom of the difference compensation structure is open, the containing space upwards exceeds the insertion core, and the pouring channel is arranged on the difference shell mold and communicated with the difference shell cavity. The difference compensation structure is embedded in the insertion core in the middle of the difference shell cavity, so that the feeding distance of the metal liquid flowing back into the difference shell cavity in the difference compensation space is reduced, the moving range of the metal liquid in the horizontal direction is widened, and then the feeding effect is enhanced.

Description

Technical Field

[0001] This disclosure belongs to the field of differential shell casting production technology, specifically relating to a differential shell forming mold assembly. Background Technology

[0002] The differential housing is one of the key components of the differential gear, and there are strict requirements for its internal shrinkage cavities and casting defects; otherwise, it will affect the overall quality and service life of the gearbox. Minor issues may lead to abnormal vehicle noises, while major issues may render the vehicle immobile or even directly affect driving safety. Therefore, research on casting processes to improve the internal density of the differential housing is essential and of great significance.

[0003] In the current differential shell casting production process, the riser is usually set at a position far from the center of the differential shell mold. The distance between the riser neck and the center of the differential shell cavity is relatively far, resulting in a long feeding distance for the molten metal in the riser. As a result, the casting formed in the differential shell cavity is prone to producing holes at the end far from the riser and riser neck. Utility Model Content

[0004] The purpose of this application is to provide a differential shell forming mold assembly, which reduces the feeding distance of the molten metal in the feeding space flowing back into the differential shell cavity by embedding the feeding structure on the insert in the middle of the differential shell cavity, thereby enhancing the feeding effect.

[0005] This disclosure provides a differential shell forming mold assembly, including:

[0006] Differential shell mold, with a differential shell cavity inside;

[0007] A ferrule is embedded in the middle of the housing cavity; the ferrule is hollow inside and has steps inside to form an installation space and a communication space that are connected vertically and bounded by the steps, and the communication space is connected to the housing cavity.

[0008] The supplementary structure has its bottom embedded in the installation space, and its outer peripheral surface is in contact with the inner sidewall of the insert. The supplementary structure protrudes upward from the insert. The interior of the supplementary structure is hollow to form a receiving space. The top of the supplementary structure is closed and the bottom is open. The receiving space extends upward beyond the insert. The receiving space communicates with the installation space and together form the supplementary space.

[0009] A pouring channel is provided on the differential shell mold and communicates with the differential shell cavity. The pouring channel is used to transport molten metal.

[0010] The molten metal in the casting channel can flow into the differential shell cavity, the connecting space and the compensation space, and the molten metal in the compensation space can flow back into the differential shell cavity.

[0011] In one exemplary embodiment of this disclosure, the connecting space includes a connecting port, and the two opposite ends of the connecting port are respectively connected to the compensation space and the differential shell cavity; the diameter of the connecting port decreases from top to bottom.

[0012] In one exemplary embodiment of this disclosure, a notch is formed on the side wall of the insert near the communication port to form a patch port. The patch port is located below the inner side of the communication port and communicates with the communication port. The patch port is connected to the housing cavity.

[0013] In one exemplary embodiment of this disclosure, the insert includes an upper mounting portion and a lower insertion portion connected to each other, wherein the orthographic projection of the lower insertion portion on the housing mold is located within the orthographic projection of the upper mounting portion on the housing mold;

[0014] The upper mounting portion is provided with the mounting space and the connecting port. The mounting space is located on the side of the connecting port away from the lower plug portion. The auxiliary port is opened on the side wall of the lower plug portion, and the auxiliary port is located on the side of the connecting port near the center of the lower plug portion. The side of the auxiliary port near the connecting port is connected to the side of the connecting port near the auxiliary port.

[0015] In one exemplary embodiment of this disclosure, the installation space includes an expansion space located between the accommodating space and the communicating space, and communicating with both the accommodating space and the communicating space.

[0016] In one exemplary embodiment of this disclosure, the differential shell mold includes:

[0017] The upper mold has an upper cavity at its bottom.

[0018] The lower mold is opposite to the upper mold, and its top has a lower cavity that corresponds one-to-one with the upper cavity. The lower cavity is connected to the upper cavity and forms the differential shell cavity.

[0019] The compensation space and the connecting space are located in the upper cavity, and the connecting space is located on the side of the compensation space closer to the lower mold, so as to communicate with the upper cavity and the lower cavity.

[0020] In one exemplary embodiment of this disclosure, the ferrule includes:

[0021] The first insert is placed in the lower cavity, and its top surface is flush with the cavity opening of the lower cavity; the outer peripheral surface of the top of the first insert is spaced apart from the surface of the lower mold.

[0022] The second insert is partially placed in the upper cavity, and the part of it protruding from the upper cavity is embedded downward in the first insert and engaged with the first insert.

[0023] Wherein, the bottom surface of the connecting space away from the compensation space is flush with the top surface of the first insert.

[0024] In one exemplary embodiment of this disclosure, the differential shell mold has a plurality of differential shell cavities arranged at intervals; each differential shell cavity is respectively embedded with a core and a compensation structure; each differential shell cavity is connected to the casting channel;

[0025] The pouring channel includes:

[0026] A vertical runner extends vertically, and its top is used to allow molten metal to enter; the vertical runner is located between the plurality of said differential shell cavities;

[0027] A horizontal runner includes a main runner and an auxiliary runner. The main runner is connected to the bottom of the vertical runner and extends between two adjacent differential shell cavities. The two ends of the auxiliary runner are respectively connected to the differential shell cavity and the main runner. At least one auxiliary runner is connected to one of the differential shell cavities.

[0028] In an exemplary embodiment of this disclosure, an exhaust channel is provided between at least two adjacent differential shell cavities, and the exhaust channel communicates with the two adjacent differential shell cavities; an exhaust pipe is provided on the top surface of the exhaust channel, the exhaust pipe communicates with the exhaust channel and protrudes upward from the exhaust pipe, and an exhaust port is provided at the top of the exhaust pipe for discharging air from inside the differential shell cavity.

[0029] In one exemplary embodiment of this disclosure, the ratio between the modulus of the connected space and the modulus of the differential cavity is greater than 1.

[0030] The technical solutions provided in this disclosure have at least the following advantages:

[0031] This embodiment of the invention embeds the insert in the middle of the cavity of the differential shell and embeds the bottom of the compensation structure in the installation space. This allows the compensation space, formed by the installation space and the accommodating space, to be located in the middle of the cavity of the differential shell. This reduces the compensation distance of the molten metal in the compensation space, increases the range of movement of the molten metal in the horizontal direction, enhances the compensation effect on the holes in the differential shell, and thus effectively improves the shrinkage and porosity defects of the differential shell and increases the internal density of the differential shell.

[0032] Moreover, compared to related technical solutions that set a sand core at a position far from the center of the differential shell cavity in the differential shell mold to facilitate the placement of the differential structure, the embodiments of this disclosure form an installation space for placing the differential structure on the original insert core in the differential shell forming mold assembly. This facilitates the placement of the differential structure and avoids setting a sand core for placing the differential structure outside the differential shell cavity. As a result, the manufacturing cost of the differential shell forming mold assembly can be reduced, and the overall space occupied by the differential shell forming mold assembly can be reduced.

[0033] This embodiment of the invention increases the pressure of the molten metal inside the compensation space by extending the accommodating space upward beyond the insert, thereby increasing the compensation pressure of the molten metal inside the compensation space. This facilitates the continuous downward flow of the molten metal inside the compensation space, thereby increasing the horizontal movement range of the molten metal inside the compensation space, improving the compensation effect of the compensation structure, and improving the problem of shrinkage and porosity in the differential shell formed by solidification in the differential shell cavity, thus improving the quality of the differential shell.

[0034] Furthermore, in this embodiment, by forming an installation space and a connecting space bounded by a step and connected vertically inside the insert, the cross-section of the connecting position between the installation space and the differential shell cavity is reduced. Thus, when the molten metal in the differential shell forming mold assembly is completely solidified and forms a casting, a stress concentration part can be formed at the connecting position between the connecting space and the differential shell cavity, so that the casting can be broken at the stress concentration part and the differential shell can be separated from the compensation structure.

[0035] Other features and advantages of this application will become apparent from the following detailed description, or may be learned in part from practice of this application.

[0036] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0037] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure. It is obvious that the drawings described below are merely some embodiments of this disclosure, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0038] Figure 1 A cross-sectional structural schematic diagram of a differential shell forming mold assembly is shown in an embodiment of this disclosure.

[0039] Figure 2 for Figure 1 A partially enlarged structural diagram.

[0040] Figure 3 It shows Figure 2 A schematic diagram of the structure of the casting formed in the process.

[0041] Figure 4 for Figure 3 A schematic diagram of the cross-sectional structure.

[0042] Figure 5 A schematic diagram of the structure of the shell in one direction is shown in an embodiment of this disclosure.

[0043] Figure 6 A schematic diagram of the differential shell in another direction is shown in an embodiment of this disclosure.

[0044] Figure 7 This illustration shows another cross-sectional structural diagram of the shell forming mold assembly in an embodiment of the present disclosure.

[0045] Figure 8 for Figure 7 A partially enlarged structural diagram.

[0046] Figure 9 It shows Figure 8 A schematic diagram of the structure of the casting formed in the process.

[0047] Figure 10 It shows Figure 8 A schematic diagram of the structure of the casting formed in the process after the first casting is removed.

[0048] Figure 11 A schematic diagram of a product structure in an embodiment of this disclosure, showing the simultaneous casting to form multiple differential shells, is shown.

[0049] Explanation of reference numerals in the attached figures:

[0050] 1. Differential shell forming mold assembly; 21. Upper mold; 22. Lower mold; 23. Differential shell cavity; 231. Upper cavity; 232. Lower cavity; 31. First insert; 32. Second insert; 321. Upper mounting part; 322. Lower insertion part; 33. Expansion space; 34. Connecting port; 35. Auxiliary port; 4. Differential structure; 41. Accommodation space; 51. Vertical runner; 521. Main runner; 522. Auxiliary runner; 53. Venting channel; 54. Venting pipe; 61. Differential shell; 62. First casting; 63. Second casting; Y, vertical. Detailed Implementation

[0051] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided to make this application more comprehensive and complete, and to fully convey the concept of the exemplary embodiments to those skilled in the art.

[0052] Furthermore, the described features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. Numerous specific details are provided in the following description to give a thorough understanding of embodiments of this application. However, those skilled in the art will recognize that the technical solutions of this application can be practiced without one or more of the specific details, or other methods, components, apparatuses, steps, etc., can be employed. In other instances, well-known methods, apparatuses, implementations, or operations are not shown or described in detail to avoid obscuring various aspects of this application.

[0053] The present application will now be described in further detail with reference to the accompanying drawings and specific embodiments. It should be noted that the technical features involved in the various embodiments described below can be combined with each other as long as they do not conflict with each other. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present application, and should not be construed as limiting the present application.

[0054] This disclosure provides a differential shell forming mold assembly 1, which may specifically include: a differential shell mold, a core insert, a differential compensation structure 4, and a gating channel.

[0055] Specifically, such as Figure 1 As shown, the differential shell mold in this embodiment of the present disclosure has a differential shell cavity 23 inside.

[0056] The internal spatial contour of the cavity 23 can be adapted to the outer contour of the product cavity 61.

[0057] The insert is embedded in the middle of the housing cavity 23. For example... Figure 2 As shown, the ferrule is hollow inside, and the ferrule has steps inside to form an installation space and a connecting space that are connected vertically by the steps. The connecting space is connected to the shell cavity 23.

[0058] The bottom of the supplementary structure 4 is embedded in the installation space, and the outer peripheral surface of the supplementary structure 4 is in contact with the inner sidewall of the insert to achieve a seal on the top of the installation space. The supplementary structure 4 protrudes upward from the insert, that is, the top surface of the supplementary structure 4 is higher than the top surface of the insert.

[0059] The internal cavity of the compensation structure 4 is hollow, forming a receiving space 41. The top of the compensation structure 4 is closed and the bottom is open, with the receiving space 41 extending upward beyond the insert. When the compensation structure 4 is installed on the insert, the receiving space 41 communicates with the installation space and together form the compensation space.

[0060] The pouring channel is located on the differential shell mold and is connected to the differential shell cavity 23. The pouring channel is used to transport molten metal.

[0061] The molten metal in the pouring channel can flow into the differential shell cavity 23, the connecting space, and the compensation space to solidify and form a casting. Before solidification, the molten metal in the compensation space can flow back into the differential shell cavity 23 through the connecting space to fill the holes on the differential shell 61 formed in the differential shell cavity 23, improve the problems of shrinkage porosity and shrinkage cavities in the differential shell 61, improve the quality of the differential shell 61, thereby improving the overall quality of the vehicle using the differential shell 61, extending the service life of the vehicle, and improving driving safety.

[0062] It should be noted that during the casting process of the differential shell, the solidification time of the molten metal in the compensation space and the connecting space is later than the solidification time of the molten metal in the differential shell cavity 23. Therefore, when the molten metal in the differential shell cavity 23 solidifies to form the differential shell 61, the molten metal in the compensation space and the connecting space that has not yet solidified can flow back down into the differential shell cavity 23 to fill the holes on the differential shell 61.

[0063] This embodiment of the present disclosure, by embedding the insert in the middle of the differential shell cavity 23 and embedding the bottom of the compensation structure 4 in the installation space, can make the compensation space formed by the installation space and the receiving space 41 located in the middle of the differential shell cavity 23. This can reduce the distance that the molten metal in the compensation space flows to the holes formed at various positions of the differential shell 61 when it flows back to the differential shell cavity 23. That is, it reduces the compensation distance of the molten metal in the compensation space, thereby increasing the range of movement of the molten metal in the horizontal direction, enhancing the compensation effect on the holes on the differential shell 61, effectively improving the shrinkage defects of the differential shell 61, and improving the internal density of the differential shell 61.

[0064] Furthermore, compared to the technical solution of setting a sand core at a position far from the center of the shell cavity 23 in the shell forming mold to facilitate the placement of the compensation structure 4, the present embodiment facilitates the placement of the compensation structure 4 by forming an installation space on the original insert in the shell forming mold assembly 1. For example, when the outer contour of the shell 61 is a non-machined surface (e.g., a petal-shaped machined surface), by installing the compensation structure 4 on the insert in the middle of the shell cavity 23, it is possible to avoid setting the compensation structure 4 or the sand core used to place the compensation structure 4 to a shape that matches the non-machined surface of the shell 61, thereby reducing the processing difficulty of the shell forming mold assembly 1. At the same time, the present disclosure also avoids setting a sand core for placing the compensation structure 4 on the outside of the shell cavity 23, thereby reducing the manufacturing cost of the shell forming mold assembly 1 and reducing the overall space occupied by the shell forming mold assembly 1.

[0065] This embodiment of the invention increases the pressure of the liquid metal inside the compensation space by extending the accommodating space 41 upward beyond the insert, thereby increasing the compensation pressure of the liquid metal inside the compensation space. This facilitates the continuous downward flow of the liquid metal inside the compensation space, thereby increasing the horizontal movement range of the liquid metal inside the compensation space, improving the compensation effect of the compensation structure 4, and improving the problem of shrinkage and porosity in the differential shell 61 formed by solidification in the differential shell cavity 23, thereby improving the quality of the differential shell 61.

[0066] Furthermore, in this embodiment, by forming an installation space and a connecting space bounded by a step and connected vertically inside the insert, the cross-section of the connecting position between the installation space and the differential shell cavity 23 is reduced. This reduces the cross-section of the connecting position between the connecting space and the differential shell cavity 23. As a result, when the molten metal in the differential shell forming mold assembly 1 is completely solidified and forms a casting, a stress concentration part can be formed at the connecting position between the connecting space and the differential shell cavity 23. This allows the casting to be broken at the stress concentration part, and the differential shell 61 to be separated from the compensation structure 4.

[0067] Specifically, such as Figures 3 to 4 As shown, the casting formed after the molten metal solidifies may include, in addition to the differential shell 61 located in the differential shell cavity 23, a first casting 62 located in the differential space and a second casting 63 located in the connecting space.

[0068] In this design, a stress concentration area is formed at the connection point between the second casting 63 and the differential shell 61, which facilitates the fracture of the casting at this connection point, thereby enabling the separation of the compensation structure 4 from the differential shell 61. Figures 5 to 6 As shown, Figure 5 and Figure 6 This is a schematic diagram of the structure of the difference shell 61 obtained after the difference structure 4 is separated from the difference shell 61 in the embodiments of this disclosure.

[0069] It should be noted that the differential shell 61 obtained after separating from the compensation structure 4 is the initial structure. The differential shell 61 needs to be further processed to obtain the differential shell product.

[0070] In some embodiments, the compensation structure 4 may be a heating riser for heating the molten metal inside, slowing down the solidification rate of the molten metal inside, and improving the feeding efficiency of the differential shell 61.

[0071] In some embodiments, the shell mold may include an upper mold 21 and a lower mold 22. For example... Figure 1 and Figure 2 As shown, the bottom of the upper mold 21 has an upper cavity 231, and the top of the lower mold 22 has a lower cavity 232.

[0072] In this mold, the lower cavity 232 in the lower mold 22 corresponds one-to-one with the upper cavity 231 in the upper mold 21. When the upper mold 21 and the lower mold 22 are positioned opposite each other, each upper cavity 231 in the upper mold 21 is connected to the corresponding lower cavity 232 in the lower mold 22, forming a shell cavity 23.

[0073] In this embodiment of the present disclosure, the compensation space and the connecting space may be located in the upper cavity 231, and the connecting space is located on the side of the compensation space near the lower cavity 232, so as to communicate with the upper cavity 231 and the lower cavity 232 respectively.

[0074] In some embodiments, the material of the shell mold may be coated sand.

[0075] In some embodiments, the insert can be disposed within the upper cavity 231 and the lower cavity 232. The top and bottom of the insert can fit against the surface of the housing mold at the position of the housing cavity 23, the middle part of the insert can be spaced apart from the surface of the housing mold, and the outer contour of the insert can be adapted to the contour of the housing 61, thereby facilitating the molding of the housing 61.

[0076] like Figure 2 As shown, in some embodiments, the insert may include: a first insert 31 and a second insert 32.

[0077] The first insert 31 can be placed inside the lower cavity 232, and its top surface can be flush with the opening of the lower cavity 232. The outer peripheral surface of the first insert 31 away from the bottom of the upper mold 21 can fit against the surface of the lower mold 22, so as to fix the first insert 31 inside the lower cavity 232. The outer peripheral surface of the first insert 31 near the top of the upper mold 21 is spaced apart from the surface of the lower mold 22, so that the lower cavity 232 can communicate with the upper cavity 231, and facilitates the formation of the differential shell cavity 23 for accommodating the differential shell 61.

[0078] The second insert 32 can be partially placed inside the upper cavity 231, and the part protruding from the upper cavity 231 is embedded downward into the first insert 31 and engaged with the first insert 31.

[0079] The outer peripheral surface of the second insert 32 away from the top of the first insert 31 can fit with the surface of the upper mold 21, and the outer peripheral surface of the second insert 32 near the bottom of the first insert 31 can be spaced apart from the surface of the upper mold 21 so that the upper cavity 231 can communicate with the lower cavity 232 and facilitate the formation of a differential shell cavity 23 that accommodates the differential shell 61.

[0080] In this embodiment, the first insert 31 and the second insert 32 can be coated sand cores. The first insert 31 and the second insert 32 can be manufactured by mounting a hot core box mold on a core-making machine.

[0081] The manufacturing process of the casting may include: first, preparing the insert, upper mold 21, and lower mold 22 respectively. Then, the insert is installed in the lower cavity 232, and the compensation structure 4 is installed in the upper cavity 231. The upper mold 21 and lower mold 22 are aligned so that the bottom of the compensation structure 4 is embedded in the installation space of the insert. Next, molten metal is injected through the pouring channel. During the solidification process, the molten metal in the differential shell cavity 23 gradually shrinks, and the molten metal in the compensation space and the connecting space flows back into the differential shell cavity 23 to compensate for the shrinkage of the casting within the differential shell cavity 23. After the molten metal has completely solidified, a casting is formed. The differential shell 61 can be separated from the compensation structure 4 by breaking the casting at the connection point between the connecting space and the differential shell cavity 23, thus obtaining the initial structure of the differential shell 61, i.e., the differential shell blank.

[0082] In some embodiments, the connecting space may be located on the side of the supplementary space near the lower mold 22, and the bottom surface of the connecting space away from the supplementary space may be flush with the top surface of the first insert 31 near the upper mold 21. However, this is not a limitation; the bottom surface of the connecting space may also be higher or lower than the top surface of the first insert 31, depending on the actual situation.

[0083] like Figure 2 As shown, in some embodiments, the connecting space may include a connecting port 34, and the two opposite ends of the connecting port 34 may be connected to the compensation space and the differential shell cavity 23 respectively, so that the molten metal in the differential shell cavity 23 can enter the compensation space through the connecting port 34.

[0084] In some embodiments, the diameter of the connecting port 34 can decrease from top to bottom, thereby reducing the cross-section at the connection position between the connecting port 34 and the differential shell cavity 23. When the molten metal is completely solidified, a stress concentration part can be formed at the connection position between the connecting port 34 and the differential shell cavity 23, so that the differential shell 61 and the compensation structure 4 can be separated at the stress concentration part.

[0085] However, this is not the only option. In addition to making the diameter of the connecting port 34 decrease from top to bottom, other technical solutions that can reduce the cross-section at the connection position between the connecting port 34 and the cavity 23 can also be included in the embodiments of this disclosure.

[0086] like Figure 7 and Figure 8 As shown, in some embodiments, a notch can be formed on the side wall of the insert near the communication port 34 to form a subsidy port 35. The subsidy port 35 is located below the inner side of the communication port 34 and communicates with the communication port 34. At the same time, the subsidy port 35 is also connected to the housing cavity 23.

[0087] Specifically, such as Figure 8As shown, the insert may include an upper mounting portion 321 and a lower insertion portion 322 connected to each other. The orthographic projection of the lower insertion portion 322 on the housing mold may be located within the orthographic projection of the upper mounting portion 321 on the housing mold. The upper mounting portion 321 may be provided with a mounting space and a communication port 34. The mounting space is located on the side of the communication port 34 away from the lower insertion portion 322. A patch port 35 is formed on the side wall of the lower insertion portion 322, and the patch port 35 is located on the side of the communication port 34 closer to the center of the lower insertion portion 322.

[0088] It should be noted that the upper mounting portion 321 and the lower insertion portion 322 in the embodiments of this disclosure may belong to the second insert 32.

[0089] In this embodiment of the present disclosure, the side of the auxiliary port 35 near the connecting port 34 is connected to the side of the connecting port 34 near the auxiliary port 35, thereby increasing the minimum cross-section of the connecting space to facilitate the flow of molten metal.

[0090] Meanwhile, since the supplement port 35 is located below the connecting port 34, and the side of the supplement port 35 away from the center of the lower insertion part 322 is connected to the differential shell cavity 23, the overall modulus of the molten metal in the connecting space can be increased, thereby increasing the ratio between the modulus of the molten metal in the connecting space and the modulus of the molten metal in the differential shell cavity 23. This effectively ensures that the solidification time of the molten metal in the connecting space is later than that of the molten metal in the differential shell cavity 23. Thus, after the differential shell 61 is formed in the differential shell cavity 23, the molten metal in the supplement space can be guaranteed to flow smoothly back to the differential shell cavity 23 through the connecting space to achieve the compensation of the differential shell 61.

[0091] It should be understood that the modulus refers to the ratio of the volume of a casting structure to its heat transfer surface area. The larger the modulus, the longer the solidification time required for the casting structure; conversely, the smaller the modulus, the shorter the solidification time.

[0092] In this embodiment of the disclosure, the ratio between the modulus of the connected space and the modulus of the differential cavity 23 is greater than 1.

[0093] For example, the ratio between the modulus of the connected space and the modulus of the differential cavity 23 can be in the range of 1.1, 1.2, 1.3, 1.4, 1.5, etc., depending on the actual situation.

[0094] In this embodiment of the disclosure, after the casting is formed, the casting can be disconnected at the connection position between the supplementary port 35 and the connecting port 34, thereby separating the differential shell 61 from the supplementary structure 4.

[0095] Specifically, in this embodiment, a first casting 62 is formed within the gap space, and a second casting 63 is formed within the connecting space. See also... Figure 9 and Figure 10 As shown, Figure 9 for Figure 8 The casting formed in the cavity 23 of the shell, Figure 10 To remove Figure 8 The structure following the first casting 62 in the formed casting. Specifically, when separating the differential shell 61 from the compensation structure 4, the second casting 63 can be disconnected at the connection point between the compensation port 35 and the connecting port 34 to obtain a differential shell blank. Subsequently, the differential shell 61 can be precision machined to obtain the differential shell product.

[0096] like Figure 2 and Figure 8 As shown, in some embodiments, the installation space may include an expansion space 33, which is located between the accommodating space 41 and the connecting space, and is connected to both the accommodating space 41 and the connecting space.

[0097] Among them, the orthographic projection of the side of the expansion space 33 near the compensation structure 4 on the differential shell mold is located within the orthographic projection of the side of the compensation structure 4 near the expansion space 33 on the differential shell mold, thereby forming a step inside the installation space, and limiting the compensation structure 4 to be located above the expansion space 33 by the step.

[0098] That is, in this embodiment, the installation space is used to accommodate the compensation structure 4, and the top of the installation space is sealed through the compensation structure 4 and the insert. The installation space forms an expansion space 33 between the accommodating space 41 and the communicating space to increase the volume of the compensation space and the volume of the molten metal contained in the compensation space. This can improve the problem that the compensation effect of the differential shell 61 is poor due to insufficient volume of molten metal contained in the compensation space.

[0099] In some embodiments, the shell mold may have a plurality of spaced-apart shell cavities 23.

[0100] Each differential shell cavity 23 is equipped with an insert and a compensation structure 4. The pouring channel can be connected to each differential shell cavity 23, which facilitates the simultaneous manufacture of multiple differential shells 61 and improves the manufacturing efficiency of the differential shells 61.

[0101] like Figure 11 As shown, in some embodiments, the pouring channel may include a vertical gating 51 and a horizontal gating. The vertical gating 51 extends vertically in the Y direction, and its top can be used to pass molten metal. The horizontal gating may include a main gating 521 and an auxiliary gating 522. The main gating 521 communicates with the bottom of the vertical gating 51 to obtain the molten metal on the vertical gating 51. The opposite ends of the auxiliary gating 522 communicate with the differential shell cavity 23 and the main gating 521, respectively, to transport the molten metal on the main gating 521 into the differential shell cavity 23 and form a differential shell 61.

[0102] In some embodiments, at least one auxiliary gating channel 522 is connected to a cavity 23.

[0103] For example, in embodiments of this disclosure, two or more auxiliary runners 522 can be connected to a differential shell cavity 23 to increase the rate of obtaining molten metal within the differential shell cavity 23, thereby improving the manufacturing efficiency of the differential shell 61.

[0104] In some embodiments, when the shell forming mold has multiple spaced-apart shell cavities 23, the vertical runner 51 can be located between the multiple shell cavities 23 to shorten the distance between the vertical runner 51 and the multiple shell cavities 23, thereby reducing the overall length of the gating channel and lowering the overall manufacturing cost of the shell forming mold assembly 1. Simultaneously, embodiments of this disclosure can also extend the main runner 521 between adjacent shell cavities 23 to shorten the distance between the main runner 521 and each shell cavity 23, reducing the length of the auxiliary runner 522, thereby lowering the overall manufacturing cost of the shell forming mold assembly 1.

[0105] In some embodiments, an exhaust channel 53 may be provided between at least two adjacent differential shell cavities 23, and the exhaust channel 53 is connected to the two adjacent differential shell cavities 23.

[0106] The top surface of the exhaust channel 53 is provided with an exhaust pipe 54, which is connected to the exhaust channel 53 and protrudes upward from the exhaust pipe 54. The top of the exhaust pipe 54 is provided with an exhaust port to discharge the air inside the shell cavity 23, thereby improving the problems of shrinkage porosity and shrinkage holes in the casting 6 and improving the quality of the casting 6.

[0107] Among them, the exhaust pipe 54 can be located in the middle of the exhaust passage 53.

[0108] It should be noted that the top surface of the exhaust channel 53 refers to the uppermost side of the exhaust channel 53 in the vertical Y direction, and the top surface and bottom surface of the exhaust channel 53 are the two opposite sides of the exhaust channel 53 in the vertical Y direction. In this embodiment of the present disclosure, the top surface of the exhaust channel 53 is located on the side of its bottom surface that is close to the compensation structure 4 in the vertical Y direction.

[0109] In the description of this specification, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "a plurality of" means two or more, unless otherwise explicitly specified.

[0110] Furthermore, it should be noted that terms such as "upper," "lower," "left," and "right" are used only for distinction and convenience of description, and do not impose any positional limitations on the embodiments of the present invention. For example, "upper" in practice can refer to "lower," "left," or "right." In this disclosure, unless otherwise explicitly specified and limited, terms such as "assembly" and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; 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. For those skilled in the art, the specific meaning of the above terms in this disclosure can be understood according to the specific circumstances.

[0111] In the description of this specification, references to terms such as "some embodiments," "exemplarily," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. The illustrative expressions of the above terms in this specification do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0112] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application. Therefore, any changes or modifications made in accordance with the claims and description of this application should fall within the scope of this patent application.

Claims

1. A differential case forming die assembly comprising: include: Differential shell mold, with an internal differential shell cavity; A ferrule is embedded in the middle of the housing cavity; the ferrule is hollow inside and has steps inside to form an installation space and a communication space that are connected vertically and bounded by the steps, and the communication space is connected to the housing cavity. The supplementary structure has its bottom embedded in the installation space, and its outer peripheral surface is in contact with the inner sidewall of the insert. The supplementary structure protrudes upward from the insert. The internal structure of the compensation structure is hollow to form a receiving space. The top of the compensation structure is closed and the bottom is open. The receiving space extends upward beyond the insert. The receiving space communicates with the installation space and together form the compensation space. A pouring channel is provided on the differential shell mold and communicates with the differential shell cavity. The pouring channel is used to transport molten metal. The molten metal in the casting channel can flow into the differential shell cavity, the connecting space and the compensation space, and the molten metal in the compensation space can flow back into the differential shell cavity.

2. The difference case forming die assembly of claim 1, wherein, The connecting space includes a connecting port, and the two opposite ends of the connecting port are respectively connected to the compensation space and the differential shell cavity; the diameter of the connecting port decreases from top to bottom.

3. The difference case forming die assembly of claim 2, wherein, A notch is formed on the side wall of the insert near the communication port to form a patch port. The patch port is located below the inside of the communication port and communicates with the communication port. The patch port is connected to the housing cavity.

4. The difference case forming die assembly of claim 3, wherein, The insert includes an upper mounting part and a lower insertion part that are connected to each other. The orthographic projection of the lower insertion part on the differential housing mold is located within the orthographic projection of the upper mounting part on the differential housing mold. The upper mounting portion is provided with the mounting space and the connecting port. The mounting space is located on the side of the connecting port away from the lower plug portion. The auxiliary port is opened on the side wall of the lower plug portion, and the auxiliary port is located on the side of the connecting port near the center of the lower plug portion. The side of the auxiliary port near the connecting port is connected to the side of the connecting port near the auxiliary port.

5. The difference case forming mold assembly of claim 1, wherein, The installation space includes an expansion space, which is located between the accommodating space and the connecting space, and is connected to both the accommodating space and the connecting space.

6. The difference case forming die assembly of claim 1 wherein, The differential shell mold includes: The upper mold has an upper cavity at its bottom. The lower mold is opposite to the upper mold, and its top has a lower cavity that corresponds one-to-one with the upper cavity. The lower cavity is connected to the upper cavity and forms the differential shell cavity. The compensation space and the connecting space are located in the upper cavity, and the connecting space is located on the side of the compensation space closer to the lower mold, so as to communicate with the upper cavity and the lower cavity.

7. The difference case forming die assembly of claim 6 wherein, The ferrule includes: The first insert is placed in the lower cavity, and its top surface is flush with the cavity opening of the lower cavity; the outer peripheral surface of the top of the first insert is spaced apart from the surface of the lower mold. The second insert is partially placed in the upper cavity, and the part of it protruding from the upper cavity is embedded downward in the first insert and engaged with the first insert. Wherein, the bottom surface of the connecting space away from the compensation space is flush with the top surface of the first insert.

8. The difference case forming die assembly of claim 1 wherein, The differential shell mold has multiple differential shell cavities arranged at intervals; each differential shell cavity is respectively embedded with a core and a compensation structure; each differential shell cavity is connected to the pouring channel; The pouring channel includes: A vertical runner extends vertically, and its top is used to allow molten metal to enter; the vertical runner is located between the plurality of said differential shell cavities; A horizontal runner includes a main runner and an auxiliary runner. The main runner is connected to the bottom of the vertical runner and extends between two adjacent differential shell cavities. The two ends of the auxiliary runner are respectively connected to the differential shell cavity and the main runner. At least one auxiliary runner is connected to one of the differential shell cavities.

9. The difference case forming die assembly of claim 1 wherein, An exhaust channel is provided between at least two adjacent differential shell cavities, and the exhaust channel is connected to the two adjacent differential shell cavities; an exhaust pipe is provided on the top surface of the exhaust channel, the exhaust pipe is connected to the exhaust channel and protrudes upward from the exhaust pipe, and an exhaust port is provided at the top of the exhaust pipe for discharging air from the differential shell cavity.

10. The differential case forming die assembly of claim 1, wherein, The ratio between the modulus of the connected space and the modulus of the differential shell cavity is greater than 1.

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