Brake disc casting device

Abstract

According to the scheme, the brake disc casting device comprises an upper sand mold and a lower sand mold located below the upper sand mold, the upper sand mold and the lower sand mold are vertically combined to form an annular mold cavity, a vertically-through first flow channel is formed in the upper sand mold, a second flow channel is formed in the lower sand mold, one side of the second flow channel is communicated with the first flow channel to form a pouring gate, and the other side of the second flow channel is communicated with the pouring gate. The other side of the second runner is communicated with the cavity so that molten metal can flow into the cavity through the pouring gate, the upper sand mold is provided with at least one overflow groove with a downward opening, and the overflow groove is communicated with the top of the cavity; the shielding structure is arranged on the lower sand mold and located in the mold cavity, the shielding structure shields part of the opening of the overflow groove, the overflow groove is formed in the top of the mold cavity, bubbles and waste residues in molten metal can be naturally accumulated in the overflow groove, the bubbles and the waste residues in the mold cavity are reduced, and the production efficiency is improved. And therefore, the pore defect problem of the upper disc surface of the formed casting is reduced, and the process yield is improved.

Description

Brake disc casting device Technical Field

[0001] This application relates to the field of brake disc casting apparatus, and particularly to a brake disc casting apparatus. Background Technology

[0002] Brake discs are critical safety components in automobiles. They use friction with brake pads to stop the wheels and are widely used in commercial vehicles. During driving, the reliable and safe braking performance of the brake discs is paramount; brake failure in an emergency can lead to accidents, even fatal ones. Therefore, the requirements for brake discs are extremely stringent. With increasing emphasis on driving safety, even higher demands are being placed on the quality of brake disc bodies.

[0003] Brake discs based on the wet sand casting process use coated sand cores to form flat discs without cylinders and flanges. The diameter of the flat disc is greater than 490mm and the thickness is less than 50mm. However, the surface of the formed casting is prone to porosity, resulting in porosity defects and reducing the yield of the process. Summary of the Invention

[0004] To address the aforementioned problems, this application provides a brake disc casting apparatus.

[0005] According to an embodiment of this application, a brake disc casting device is disclosed. The brake disc casting device includes an upper sand mold and a lower sand mold located below the upper sand mold. The upper sand mold and the lower sand mold are joined together to form an annular cavity. The upper sand mold has a first flow channel that runs vertically through it. The lower sand mold has a second flow channel. One side of the second flow channel communicates with the first flow channel to form a gating. The other side of the second flow channel communicates with the cavity so that molten metal can flow into the cavity through the gating. The upper sand mold has at least one overflow groove with an opening facing downwards. The overflow groove communicates with the top of the cavity.

[0006] A shielding structure is provided in the lower sand mold and located inside the cavity, the shielding structure shielding part of the opening of the overflow groove.

[0007] In one exemplary embodiment, the overflow groove forms a closed groove structure along the circumference of the cavity;

[0008] One of the overflow channels is connected to the outer periphery of the top of the cavity; and / or one of the overflow channels is connected to the inner periphery of the top of the cavity.

[0009] In one exemplary embodiment, one of the overflow channels is an external overflow channel, which is connected to the top outer periphery of the cavity;

[0010] The shielding structure shields the outer overflow channel around the circumferential side away from the center of the cavity.

[0011] The width of the cross section connecting the unobstructed opening of the overflow channel and the cavity is 2.5mm to 4.5mm.

[0012] In one exemplary embodiment, one of the overflow channels is an inner overflow channel, which is connected to the top of the inner periphery of the cavity;

[0013] The shielding structure is formed on the top surface of the middle part of the lower sand mold and shields the inner overflow groove along the axial direction near the center of the cavity.

[0014] The width of the cross section connecting the unobstructed opening of the inner overflow groove and the cavity is 1mm to 2.5mm.

[0015] In one exemplary embodiment, the diameter of the overflow channel gradually increases from top to bottom; and / or

[0016] The inner wall of the overflow channel is an arc-shaped inner wall; and / or

[0017] The opening of the overflow channel transitions to the bottom of the upper sand mold with a rounded corner; and / or

[0018] The overflow channel extends in a ring shape; and / or

[0019] The overflow channel includes a plurality of first and second channels arranged in an alternating manner, wherein the depth of the first channel is greater than the depth of the second channel, and / or the diameter of the first channel is greater than the diameter of the second channel; and / or

[0020] The bottom of the first flow channel is covered with a filter screen.

[0021] In one exemplary embodiment, the gating system is connected to the middle of the cavity;

[0022] The second flow channel is disposed at the top of the lower sand mold; the second flow channel includes a pouring socket and at least three transverse flow channels, the opening of the pouring socket faces upward and is connected to the bottom end of the first flow channel, one end of the plurality of transverse flow channels is connected to the pouring socket at intervals, and the other end of the transverse flow channels extends horizontally in a direction away from the pouring socket and is connected to the cavity.

[0023] In one exemplary embodiment, the transverse flow channels include four channels, which are arranged in a cross shape in a circumferential array along the casting socket; and / or

[0024] The first flow channel includes a pouring cup and a straight channel connected sequentially from top to bottom. The lateral cross-sectional area of ​​the straight channel is 1.4 to 1.7 times the sum of the vertical cross-sectional areas of all the lateral flow channels; and / or

[0025] The depth of the casting cavity is greater than the depth of the transverse flow channel; the inner bottom surface of the casting cavity and the inner bottom surface of the transverse flow channel are smoothly transitioned with rounded corners; and / or

[0026] The depth of the transverse flow channel is 3mm to 5mm.

[0027] In one exemplary embodiment, the upper sand mold is provided with a plurality of vertically penetrating vent pins spaced apart, the vent pins being internally open and communicating with the mold cavity and / or the overflow groove.

[0028] In one exemplary embodiment, the position of the venting needle is offset from the liquid outlet of the gating system;

[0029] At least one exhaust needle is provided between two adjacent transverse flow channels.

[0030] In one exemplary embodiment, the top of the lower sand mold is provided with an annular placement cavity, the outer annular wall of the placement cavity forms the outer periphery of the cavity, and the inner annular wall of the placement cavity forms the inner periphery of the cavity;

[0031] The shielding structure includes a sand core disposed within the cavity, the top side of the sand core shielding a portion of the opening of the overflow groove;

[0032] The sand core includes a partition and an outer connecting block arranged around the outer periphery of the partition. The partition is annular, and the inner periphery of the partition is spaced apart from the inner annular wall of the placement cavity. The partition is spaced apart from both the upper and lower sand molds. The partition is provided with a plurality of air duct rib through holes spaced apart. The outer peripheral wall of the outer connecting block is attached to the outer annular wall of the placement cavity. The bottom surface of the outer connecting block protrudes downward relative to the bottom surface of the partition and extends to the lower sand mold. The top surface of the outer connecting block protrudes upward relative to the top surface of the partition and extends to the upper sand mold. The top of the outer connecting block covers the outer overflow groove circumferentially away from the center of the cavity.

[0033] The technical solutions provided by the embodiments of this application have at least the following beneficial effects:

[0034] The brake disc casting apparatus disclosed in this application constructs an overflow groove at the top of the mold cavity. This allows air bubbles and slag in the molten metal to naturally accumulate within the overflow groove, reducing air bubbles and molten metal slag in the mold cavity. This, in turn, reduces porosity defects on the surface of the cast disc, improving the yield rate. Simultaneously, the shielding structure reduces the cross-sectional area connecting the overflow groove and the mold cavity. After casting, the connection between the overflow block formed at the overflow groove location and the brake disc product is reduced, facilitating the removal of the overflow block by workers and minimizing damage to the brake disc surface, further improving the yield rate.

[0035] It should be understood that the above general description and the following detailed description are merely exemplary and do not limit this application. Attached Figure Description

[0036] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the specification, serve to explain the principles of this application.

[0037] Figure 1 is a schematic diagram of the composition of a brake disc casting device provided in an embodiment of this application.

[0038] Figure 2 is a schematic diagram of the structure of the upper sand mold provided in an embodiment of this application.

[0039] Figure 3 is a schematic diagram of the lower sand mold provided in an embodiment of this application.

[0040] Figure 4 is a schematic diagram of the structure of a sand core provided in an embodiment of this application.

[0041] Figure 5 is an exploded structural diagram of a brake disc casting device provided in an embodiment of this application.

[0042] Figure 6 is a structural diagram of a casting provided in an embodiment of this application.

[0043] The reference numerals in the attached drawings are explained as follows: 1-Brake disc casting device, 11-Cavity, 12-Gateway, 13-Upper sand mold, 131-First runner, 132-Overflow groove, 1321-Outer overflow groove, 1322-Inner overflow groove, 1323-First tank, 1324-Second tank, 14-Lower sand mold, 141-Second runner, 1411-Pouring socket, 1412-Transverse runner, 142-Placement cavity, 143-Slot, 15-Exhaust pin, 16-Sand core, 161-Baffle plate, 1611-Air duct rib through hole, 162-Outer connecting block, 163-Slot, 2-Casting, 21-Overflow block, 211-Outer overflow block, 212-Inner overflow block, 22-Straight sprue block, 23-Inner sprue plate, 24-Ventilation hole. Detailed Implementation

[0044] 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, they are provided so that the description of this application will be more complete and fully convey the concept of the exemplary embodiments to those skilled in the art.

[0045] In the description of this utility model, all the connection relationships mentioned do not refer to direct connection of components, but rather to the ability to form a better connection structure by adding or reducing connecting accessories according to specific implementation conditions. The various technical features in this utility model can be combined interactively without contradicting each other.

[0046] In the description of this utility model, unless otherwise explicitly defined, terms such as setting, installing, and connecting should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this utility model in conjunction with the specific content of the technical solution.

[0047] In the description of this utility model, it should be understood that the directional descriptions, such as up, down, front, back, left, right, etc., indicate the directional or positional relationship based on the directional or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0048] In the description of this utility model, "several" means one or more, "multiple" means two or more, "greater than", "less than", "exceeding" etc. are understood to exclude the number itself, and "above", "below", "within" etc. are understood to include the number itself.

[0049] This utility model provides a brake disc casting device 1 for casting brake disc products. During the brake disc manufacturing process, a cavity 11 corresponding to the shape of the product is formed inside the brake disc casting device 1. Then, high-temperature molten metal is poured into the cavity 11 from the gating system 12, so that the molten metal cools and solidifies in the cavity 11 to form the required casting 2.

[0050] Figure 1 shows a cross-sectional view of the brake disc casting device 1. Figure 6 shows the casting 2 formed by the brake disc casting device 1.

[0051] Referring to Figure 1, the brake disc casting device 1 of this application includes an upper sand mold 13, a lower sand mold 14, and a shielding structure. The lower sand mold 14 is located below the upper sand mold 13, and the upper sand mold 13 and the lower sand mold 14 are joined together to form an annular cavity 11. The upper sand mold 13 has a first flow channel 131 that runs vertically through it, and the lower sand mold 14 has a second flow channel 141. One side of the second flow channel 141 communicates with the first flow channel 131 to form a gating 12, and the other side of the second flow channel 141 communicates with the cavity 11, so that molten metal can flow from the outside into the cavity 11 through the gating 12.

[0052] The upper sand mold 13 is provided with at least one downward-facing overflow groove 132, which is connected to the top of the cavity 11. During the cooling process of the molten metal, the waste residue and air bubbles inside can enter the overflow groove 132. Referring to Figure 6, after the casting 2 is formed, an overflow block 21 is formed on the casting 2 at the position corresponding to the overflow groove 132. The waste residue and air bubbles after the metal cooling are located on the overflow block 21, which reduces the air bubble defects on the surface of the casting 2. After shot blasting the casting 2, the workers can remove the overflow block 21, as well as the gating block and gating plate, etc., thereby obtaining the brake disc product and improving the process yield.

[0053] A shielding structure is installed in the lower sand mold 14 and located inside the cavity 11, shielding a portion of the opening of the overflow groove 132. The overflow groove 132 communicates with the cavity 11 through its opening. The shielding structure is installed in the lower sand mold 14 and protrudes towards the overflow groove 132, thereby shielding a portion of the opening of the overflow groove 132. This reduces the cross-sectional area of ​​communication between the overflow groove 132 and the cavity 11. After the casting 2 is formed, the connection position between the overflow block 21 formed at the overflow groove 132 and the brake disc product is reduced, making it easier for workers to remove the overflow block 21 and reducing damage to the surface of the brake disc product.

[0054] This application constructs an overflow groove 132 at the top of the cavity 11, allowing air bubbles and slag in the molten metal to naturally accumulate within the overflow groove 132. This reduces air bubbles and molten metal slag in the cavity 11, thereby reducing porosity defects on the surface of the cast part 2 after molding and improving the process yield. Simultaneously, the shielding structure reduces the cross-sectional area connecting the overflow groove 132 and the cavity 11. After the casting 2 is formed, the connection point between the overflow block 21 formed at the overflow groove 132 and the brake disc product is reduced, facilitating the removal of the overflow block 21 by workers, reducing damage to the surface of the brake disc product, and further improving the process yield.

[0055] The casting process of this application adopts the flat-pan mold sand casting process. Mold sand is filled into the upper mold and the lower mold to prepare the upper sand mold 13 and the lower sand mold 14. The upper sand mold 13 is provided with a first flow channel 131, and the lower sand mold 14 is provided with a second flow channel 141. The upper sand mold 13 and the lower sand mold 14 are joined together to form a cavity 11. The molten metal can enter the cavity 11 through the first flow channel 131 and the second flow channel 141 in sequence.

[0056] Figure 2 shows a schematic diagram of the upper sand mold 13, with the bottom surface of the upper sand mold 13 shown in the view direction.

[0057] Referring to Figures 1 and 2, the upper sand mold 13 has a first flow channel 131 that runs vertically through it. Specifically, as shown in Figure 1, the first flow channel 131 includes a pouring cup and a straight channel connected sequentially from top to bottom. The opening of the pouring cup is formed on the top surface of the upper sand mold 13, and the diameter of the pouring cup gradually decreases from top to bottom. The straight channel extends vertically, with its top end connected to the bottom of the pouring cup and its bottom end penetrating downwards through the bottom surface of the upper sand mold 13. Molten metal can enter the first flow channel 131 through the pouring cup and naturally flow downwards through the straight channel under the action of gravity. Furthermore, the bottom end of the first flow channel is covered with a filter screen. Specifically, the bottom end of the straight channel in this application is covered with a filter screen made of cast iron. The cast iron filter screen can effectively remove harmful impurities such as bubbles, ash oxides, and various inclusions from the molten metal, thereby eliminating air holes, slag holes, and sand holes in the casting 2, and significantly improving the yield of the casting 2.

[0058] The upper sand mold 13 is provided with at least one overflow groove 132 with its opening facing downwards. Specifically, as shown in Figure 1, the bottom plane of the upper sand mold 13 forms the top surface of the cavity 11. Referring to Figures 1 and 2, the bottom surface of the upper sand mold 13 is provided with at least one overflow groove 132, and the overflow groove 132 is connected to the top of the cavity 11. The molten metal can fill the cavity 11 and the overflow groove 132. The waste residue, impurities, and bubbles in the part of the molten metal located in the cavity 11 will float upwards and flow into the overflow groove 132.

[0059] Furthermore, as shown in Figure 2, the overflow groove 132 forms a closed groove structure along the circumference of the cavity 11. The overflow groove 132 can extend around the circumference of the cavity 11, which facilitates the discharge of air bubbles and waste into the overflow groove 132 along the circumference of the cavity 11 by the molten metal filling the cavity 11, further reducing the bubble defects on the surface of the casting 2 and improving the process yield.

[0060] In this embodiment, the overflow groove 132 has an annular shape. The annular overflow groove 132 fits snugly against the annular cavity 11, not only balancing the flow of molten metal within the cavity 11, but also uniformly collecting impurities, gases, and paint fragments from the molten metal, preventing these substances from entering the casting 2 body and thus improving the surface quality of the casting 2. Furthermore, the overflow groove 132 can also be rectangular, elliptical, or other closed shapes.

[0061] Furthermore, the diameter of the overflow channel 132 gradually increases from top to bottom. The diameter of the overflow channel 132 is the distance between the two opposite sides of the overflow channel 132 extending along its length. The distance between the two opposite sides of the overflow channel 132 gradually increases from top to bottom, making the opening of the overflow channel 132 wider, which facilitates the inflow of molten metal.

[0062] Furthermore, the inner wall of the overflow channel 132 is an arc-shaped inner wall. The arc-shaped inner wall forms the inner side and bottom surface of the overflow channel 132, preventing the formation of sharp angles within the overflow channel 132, facilitating the smooth flow of molten metal, and thereby promoting the floating of bubbles and slag in the molten metal into the overflow channel 132.

[0063] Furthermore, the opening of the overflow channel 132 transitions to the bottom of the upper sand mold 13 with a rounded corner. Specifically, the bottom surface of the upper sand mold 13 and the inner surface of the overflow channel 132 are connected by a rounded corner, the center of which faces away from the cavity 11, making the transition between the bottom surface of the upper sand mold 13 and the inner surface of the overflow channel 132 smoother, facilitating smooth flow of molten metal, and further promoting the floating of bubbles and slag in the molten metal into the overflow channel 132. In fact, the two ends of the rounded corner along the arc-shaped extension direction can also be tangent to the bottom surface of the upper sand mold 13 and the inner surface of the overflow channel 132, respectively.

[0064] In order to facilitate the collection of air bubbles and metal slag in the molten metal, in this embodiment, an overflow channel 132 is connected to the outer periphery of the top of the cavity 11; and / or an overflow channel 132 is connected to the inner periphery of the top of the cavity 11.

[0065] The overflow groove 132 located on the outer periphery of the top of the cavity 11 is called the outer overflow groove 1321. During the process of molten metal filling the cavity 11, it is convenient for air and other gases to escape from the location of the outer overflow groove 1321, reducing the formation of air bubbles in the product.

[0066] The overflow groove 132 located on the inner periphery of the top of the cavity 11 is called the inner overflow groove 1322. The inner overflow groove 1322 can not only collect air bubbles and metal slag near the inner periphery of the cavity 11, but also collect excess material flow, thereby reducing defects such as shrinkage cavities and voids inside the product.

[0067] Specifically, the overflow groove 132 of this application may be provided only once. It may be that only one outer overflow groove 1321 is provided on the upper sand mold 13, or only one inner overflow groove 1322 is provided on the upper sand mold 13. In this embodiment, the overflow groove 132 on the upper sand mold 13 includes an outer overflow groove 1321 and an inner overflow groove 1322. The outer overflow groove 1321 is connected to the top outer periphery of the cavity 11, and the inner overflow groove 1322 is connected to the top inner periphery of the cavity 11. That is, the outer overflow groove 1321 is arranged at an inner and outer interval around the outer periphery of the inner overflow groove 1322. Here, "outer" refers to the direction away from the central axis of the cavity 11, and "inner" refers to the direction close to the central axis of the cavity 11.

[0068] Furthermore, the overflow channel 132 includes a plurality of first channels 1323 and second channels 1324 arranged in a staggered manner, wherein the depth of the first channel 1323 is greater than the depth of the second channel 1324, and / or the diameter of the first channel 1323 is greater than the diameter of the second channel 1324.

[0069] The overflow tank 132 is structured with a first tank 1323 that is deeper and a second tank 1324 that is shallower, arranged alternately in sequence. This allows the molten metal to form an overflow block 21 of uneven thickness after the overflow tank 132 is formed, which facilitates the removal of the overflow block 21 in the future.

[0070] Furthermore, the diameter of the first tank 1323 is the distance between the two opposite side walls extending along the length of the first tank 1323, hereinafter referred to as the width of the first tank 1323. The diameter of the second tank 1324 is the distance between the two opposite side walls extending along the length of the overflow channel 132 of the second tank 1324, hereinafter referred to as the width of the second tank 1324. In this embodiment, the structure of the overflow channel 132 can be configured such that the wider first tank 1323 and the narrower second tank 1324 are alternately arranged, so that the molten metal can form overflow blocks 21 of varying widths after the overflow channel 132 is formed. In fact, the bottom surface of the upper sand mold 13 corresponding to the narrower second tank 1324 can facilitate the positioning and pressing of the sand core 16, preventing the sand core 16 from floating.

[0071] In this embodiment, at least a portion of the depth and width of the first groove 1323 are greater than the depth and width of the second groove 1324. Alternatively, only the depth of the first groove 1323 may be greater than the depth of the second groove 1324, or only the diameter width of the first groove 1323 may be greater than the diameter width of the second groove 1324.

[0072] Specifically, the external overflow channel 1321 includes a first channel 1323 and a second channel 1324 that are arranged in an alternating manner, and similarly, the internal overflow channel 1322 also includes a first channel 1323 and a second channel 1324 that are arranged in an alternating manner.

[0073] Furthermore, the upper sand mold 13 is provided with a plurality of vertically penetrating venting pins 15 spaced apart. Each venting pin 15 is internally open and communicates with the mold cavity 11 and / or the overflow groove 132. The connection of the venting pin 15 to the overflow groove 132 facilitates gas discharge. In this embodiment, the venting pin 15 is connected to the outer overflow groove 1321 and located at the outer edge of the mold cavity 11, effectively preventing sand hole defects. Alternatively, the venting pin 15 can also be connected to the inner overflow groove 1322.

[0074] In some other embodiments, the venting needle 15 may be connected to the top of the cavity 11 alone, or the venting needle 15 may be connected to the overflow groove 132 alone, or multiple venting needles 15 may be connected to the cavity 11 and the overflow groove 132 respectively.

[0075] Furthermore, the position of the venting pin 15 is offset from the liquid outlet of the gating 12. The temperature of the cavity 11 corresponding to the liquid outlet of the gating 12 is relatively high. The position of the venting pin 15, which is offset from the liquid outlet of the gating 12, is located in the cavity 11 where the cooling rate is relatively fast, which can collect the rising gas in time and reduce the porosity defects of the casting 2.

[0076] Figure 3 shows a schematic diagram of the lower sand mold 14, with the top surface of the lower sand mold 14 shown in the view direction.

[0077] Referring to Figures 1 and 3, the upper sand mold 13 and the lower sand mold 14 are joined together to form an annular cavity 11. The lower sand mold 14 has a second runner 141, which connects the first runner 131 and the cavity 11. The first runner 131 and the second runner 141 are connected to form a gating system 12. Molten metal enters the cavity 11 sequentially through the first runner 131 and the second runner 141.

[0078] In this embodiment, the gating system 12 is connected to the center of the cavity 11. Molten metal can be poured into the annular cavity 11 from the center and diffuse towards the periphery of the cavity 11, shortening the flow path of the molten metal, reducing the temperature difference within the cavity 11, and slowing down the temperature drop of the molten metal within the cavity 11. This facilitates gas rise, reduces the generation of porosity on the casting 2, reduces porosity defects, and improves product quality. Simultaneously, the shortened molten metal flow path reduces the weight of the gating system. Furthermore, the reduced bubble generation allows for a lower requirement for the venting pin 15, further reducing the weight of the brake disc casting device 1.

[0079] In some other embodiments, the gating system 12 may be connected to the outside of the cavity 11. Molten metal can enter the cavity 11 from one side and diffuse towards the opposite side of the cavity 11, simplifying the gating system structure.

[0080] Furthermore, the second flow channel 141 is located at the top of the lower sand mold 14.

[0081] The second flow channel 141 includes a casting cavity 1411, the casting cavity 1411 having an upward opening that faces and connects to the bottom end of the first flow channel 131.

[0082] The second runner 141 also includes at least three transverse runners 1412, one end of which is connected to the casting cavity 1411 at intervals, and the other end of which extends horizontally in a direction away from the casting cavity 1411 and is connected to the cavity 11.

[0083] The pouring cup, straight channel, pouring socket 1411, and transverse flow channel 1412 are connected in sequence. The molten metal flowing out from the straight channel flows downward into the pouring socket 1411. The pouring socket 1411 can control the speed and flow rate of the molten metal entering the second flow channel 141, thereby controlling the speed and flow rate of the molten metal flowing into the mold cavity 11 through the transverse flow channel 1412. This prevents the molten metal from flowing too fast, reduces gas entrainment and eddy formation, and reduces the impact on the mold cavity 11, thereby reducing casting defects.

[0084] The portion of the molten metal that is formed in the first runner 131 is the sprue block 22 of the casting 2, and the portion of the molten metal that is formed in the second runner 141 is the ingate strip 23 of the casting 2.

[0085] In this embodiment, the depth of the casting cavity 1411 is greater than the depth of the transverse flow channel 1412. The deeper casting cavity 1411 can buffer the incoming molten metal, preventing the molten metal from directly rushing into the mold cavity 11.

[0086] The inner bottom surface of the casting socket 1411 and the inner bottom surface of the transverse flow channel 1412 are smoothly transitioned with rounded corners. Specifically, the inner bottom surface of the casting socket 1411 and the inner bottom surface of the transverse flow channel 1412 can be smoothly transitioned with an arc surface, that is, the inner bottom surface of the casting socket 1411 and the inner sidewall of the casting socket 1411 are transitioned with an arc surface with the arc center facing towards the casting socket 1411, and the inner sidewall of the casting socket 1411 and the inner bottom surface of the transverse flow channel 1412 are transitioned with an arc surface with the arc center facing away from the second flow channel 141, which facilitates the smooth entry of molten metal from the casting socket 1411 into the transverse flow channel 1412.

[0087] At least three transverse flow channels 1412 are provided to increase the path for molten metal to enter the cavity 11 and improve the efficiency of molten metal pouring.

[0088] Furthermore, multiple transverse flow channels 1412 are arranged sequentially and at intervals along the circumference of the casting cavity 1411. The multiple transverse flow channels 1412 are arranged radially relative to the casting cavity 1411, allowing the molten metal to enter the cavity 11 more evenly from the multiple transverse flow channels 1412, further reducing the rate of temperature drop of the molten metal in the cavity 11, which is conducive to gas floating, reducing porosity defects, and improving product quality.

[0089] In this embodiment, four transverse runners 1412 are arranged in a cross shape along the circumferential array of the casting cavity 1411. The four transverse runners 1412 improve the efficiency of molten metal casting and are convenient to design; after the casting 2 is formed, having four transverse runners 1412 also makes them easy to remove. In other embodiments, three, five, or six transverse runners 1412 may be provided. In fact, the array distribution of the transverse runners 12, i.e., the consistent spacing between any two adjacent transverse runners 1412, further improves the uniformity of molten metal entering the mold cavity 11. The casting cavity 1411 of this application is cross-shaped, which facilitates guiding the molten metal to flow to the four transverse runners 1412 respectively.

[0090] In this embodiment, the depth of the transverse runner 1412 is 3mm to 5mm, which ensures that the molten metal passes through the transverse runner 1412 and enters the cavity 11. At the same time, the relatively thin transverse runner 1412 facilitates the removal of the subsequent ingate 12.

[0091] Furthermore, the transverse cross-sectional area of ​​the straight channel is 1.4 to 1.7 times the sum of the vertical cross-sectional areas of all transverse flow channels 1412. The larger transverse cross-sectional area of ​​the straight channel reduces pressure loss in the molten metal, ensuring that the molten metal maintains a certain pressure and flows smoothly, evenly, and effectively into the mold cavity 11 during the casting process. Simultaneously, the molten metal can enter the mold cavity 11 from the gating system at a higher flow rate and a stable flow rate. This reduces temperature drop and oxidation of the molten metal, avoiding casting defects caused by excessively slow or uneven flow rates, thereby improving the quality and consistency of the casting 2.

[0092] Furthermore, at least one venting pin 15 is provided between two adjacent transverse flow channels 1412 to uniformly collect the gas formed in the cooling zone within the cavity 11, further reducing porosity defects in the casting 2. In this embodiment, four venting pins 15 are provided, connected to the overflow groove 1321, and located between two adjacent transverse flow channels 1412. In addition, the upper sand mold 13 can also be provided with two or three venting pins 15 at positions corresponding to two adjacent transverse flow channels 1412. In some other embodiments, if the gating system 12 is connected to one side of the cavity 11, then multiple venting pins 15 can be connected at intervals to the top of the other side of the cavity 11.

[0093] As shown in Figure 3, the top of the lower sand mold 14 is provided with an annular placement cavity 142. After the upper sand mold 13 and the lower sand mold 14 are aligned to form the cavity 11, the outer annular wall of the placement cavity 142 forms the outer periphery of the cavity 11, and the inner annular wall of the placement cavity 142 forms the inner periphery of the cavity 11. Part of the bottom surface of the upper sand mold 13 forms the top surface of the cavity 11. The second flow channel 141 is located in the middle of the lower sand mold 14. Specifically, the middle part of the lower sand mold 14 protrudes upward relative to the placement cavity 142. The casting socket 1411 is located at the center of the placement cavity 142. One end of the four transverse flow channels 1412 is connected to the casting socket 1411, and the other end extends away from the casting socket 1411 and is connected to the placement cavity 142.

[0094] The brake disc casting device 1 of this application also includes a shielding structure, which is disposed on the lower sand mold 14 and located within the cavity 11. It is understood that the shielding structure may be integrally disposed with the lower sand mold 14, or the shielding structure may be separately disposed from the lower sand mold 14.

[0095] In some embodiments, a shielding structure is formed on the top surface of the lower sand mold 14 and shields the inner overflow groove 1322 axially upwards near the center of the cavity 11. Specifically, the inner overflow groove 1322 communicates with the top of the inner periphery of the cavity 11. In this embodiment, the shielding structure is integrally formed with the lower sand mold 14, and the shielding structure protrudes from the middle of the lower sand mold 14 toward the upper sand mold 13. In fact, the shielding structure is outside the cavity 11 and fits against the inner periphery of the cavity 11, so that the shielding structure can approach the inner overflow groove 1322 of the upper sand mold 13. In this embodiment, the transverse flow channel 1412 and the casting cavity 1411 are formed at the central protrusion of the lower sand mold 14. The outer edge of the central protrusion of the lower sand mold 14 extends in accordance with the circumferential shape of the inner overflow groove 1322, and the outer edge of the central protrusion of the lower sand mold 14 can block the inner circumferential side of the inner overflow groove 1322 near the center of the cavity 11 along the circumferential direction. That is, the central protrusion of the lower sand mold 14 blocks the inner circumferential side of the opening of the inner overflow groove 1322, so that the molten metal can enter the inner overflow groove 1322 from the outer circumferential side of the opening of the inner overflow groove 1322.

[0096] Furthermore, the width of the cross-section connecting the unobstructed opening of the inner overflow groove 1322 and the cavity 11 is 1mm to 2.5mm. That is, molten metal can enter the inner overflow groove 1322 through the cross-section connecting the unobstructed opening of the inner overflow groove 1322 and the cavity 11. At the same time, the cross-section connecting the cavity 11 and the inner overflow groove 1322 is set to a smaller value. After the casting 2 is formed, an inner overflow block 212 is formed on the casting 2 at the position corresponding to the inner overflow groove 1322, reducing the connection thickness between the inner overflow block 212 and the casting 2, making it easier to remove the inner overflow block 212 from the casting 2 later.

[0097] Figure 4 shows a schematic diagram of the sand core 16. Figure 5 shows an exploded view of the brake disc casting device 1.

[0098] Furthermore, referring to Figures 1, 4 and 5, the shielding structure includes a sand core 16, which is disposed within the cavity 11, and the top side of the sand core 16 shields a portion of the opening of an overflow groove 132.

[0099] Specifically, the sand core 16 and the lower sand mold 14 are separately configured, with the sand core 16 located within the placement cavity 142 of the lower sand mold 14. A locking block 163 is provided on the outer surface of the sand core 16, and a corresponding locking groove 143 is provided on the outer circumferential wall of the placement cavity 142 of the lower sand mold 14. When the sand core 16 is placed on the lower sand mold 14, the locking block 163 and the locking groove 143 can be fitted together to achieve circumferential positioning of the sand core 16 and the lower sand mold 14, preventing the sand core 16 from floating and rotating relative to the lower sand mold 14.

[0100] Furthermore, the overflow channel 1321 is connected to the top outer periphery of the cavity 11, and the shielding structure shields the overflow channel 1321 circumferentially away from the center of the cavity 11. In fact, the shielding structure here is a sand core 16, the top of which shields the overflow channel 1321 circumferentially away from the center of the cavity 11. That is, molten metal can enter the overflow channel 1321 from the inner periphery of its opening.

[0101] Specifically, the sand core 16 includes a partition 161 and an outer connecting block 162 surrounding the outer periphery of the partition 161. The partition 161 is annular, with its inner annular periphery spaced apart from the inner annular wall of the placement cavity 142. The partition 161 is also spaced apart from both the upper sand mold 13 and the lower sand mold 14. Multiple air duct through holes 1611 are spaced apart on the partition 161. The partition 161 is suspended between the upper sand mold 13 and the lower sand mold 14, dividing the cavity 11 into upper and lower chambers. The air duct through holes 1611 connect the upper and lower chambers, and the spaced annular periphery of the partition 161 with the inner annular wall of the placement cavity 142 allows the molten metal to flow and fill the entire cavity 11. After casting 2 is formed, air ducts are formed at the positions corresponding to the air duct through holes 1611, and the internal cavity of the brake disc is formed at the positions corresponding to the partition 161. The inner circumference of the partition 161 is provided with multiple air duct strips at intervals along the circumference. The upward-curving air duct strips and the downward-curving air duct strips are arranged alternately, and the air duct strips can form 24 ventilation holes.

[0102] The outer peripheral wall of the outer connecting block 162 fits against the outer ring wall of the placement cavity 142. The bottom surface of the outer connecting block 162 convexes downward relative to the bottom surface of the partition plate 161 and extends to the lower sand mold 14. The top surface of the outer connecting block 162 convexes upward relative to the top surface of the partition plate 161 and extends to the upper sand mold 13. After casting, the inner peripheral wall of the outer connecting block 162 can correspondingly form the outer peripheral wall of the casting 2.

[0103] Furthermore, the top side of the sand core 16 obstructs a portion of the opening of an overflow channel 132.

[0104] Specifically, the top side of the sand mold, i.e., the top of the outer connecting block 162, blocks the outer overflow channel 1321 circumferentially away from the center of the cavity 11. That is, the outer connecting block 162 is annular, and the outer connecting block 162 and the outer overflow channel 1321 are concentrically arranged. The outer diameter of the inner peripheral wall of the outer connecting block 162 is slightly larger than the outer diameter of the inner peripheral wall of the outer overflow channel 1321, so that the outer connecting block 162 can block the outer peripheral side of the opening of the outer overflow channel 1321 circumferentially, and the molten metal can enter the outer overflow channel 1321 from the inner peripheral side of the opening of the outer overflow channel 1321.

[0105] Furthermore, the width of the unobstructed opening of the overflow channel 1321 communicating with the cavity 11 is 2.5mm to 4.5mm. This allows molten metal to enter the overflow channel 1321 from the communicating section between the overflow channel 1321 and the cavity 11. Simultaneously, the small communicating section between the overflow channel 1321 and the cavity 11 results in an overflow block 211 forming on the casting 2 at the position corresponding to the overflow channel 1321 after casting 2 is formed. The thickness of the overflow block 211 on the casting 2 is also relatively thin, facilitating its removal after casting 2 is formed.

[0106] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the utility models disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this application are indicated by the appended claims.

Claims

1. A brake disc casting device, characterized in that, include: An upper sand mold and a lower sand mold located below the upper sand mold are arranged vertically to form an annular cavity. The upper sand mold has a first flow channel that runs vertically through it, and the lower sand mold has a second flow channel. One side of the second flow channel communicates with the first flow channel to form a gating system, and the other side of the second flow channel communicates with the cavity so that molten metal can flow into the cavity through the gating system. The upper sand mold has at least one overflow groove with its opening facing downwards, and the overflow groove communicates with the top of the cavity. A shielding structure is provided in the lower sand mold and located inside the cavity, and the shielding structure shields part of the opening of the overflow groove.

2. The brake disc casting device according to claim 1, characterized in that, The overflow channels form a closed channel structure along the circumference of the cavity; one of the overflow channels is connected to the outer periphery of the top of the cavity; and / or one of the overflow channels is connected to the inner periphery of the top of the cavity.

3. The brake disc casting device according to claim 2, characterized in that, The overflow channel is an external overflow channel, which is connected to the top outer periphery of the cavity; the shielding structure shields the external overflow channel circumferentially away from the center of the cavity; the width of the unshielded opening of the external overflow channel and the cross-section connecting the cavity is 2.5mm to 4.5mm.

4. The brake disc casting device according to claim 2, characterized in that, The overflow groove is an inner overflow groove, which is connected to the top of the inner periphery of the cavity; the shielding structure is formed on the top surface of the middle part of the lower sand mold, and shields the inner overflow groove along the axial direction near the center of the cavity; the width of the unshielded opening of the inner overflow groove and the cross section connecting the cavity is 1mm~2.5mm.

5. The brake disc casting device according to claim 1, characterized in that, The overflow channel diameter gradually increases from top to bottom; and / or the inner wall of the overflow channel is an arc-shaped inner wall; and / or the opening of the overflow channel transitions to the bottom of the upper sand mold with a rounded corner; and / or the extension shape of the overflow channel is annular; and / or the overflow channel includes a plurality of first and second channels arranged in a staggered manner, the depth of the first channel is greater than the depth of the second channel, and / or the diameter of the first channel is greater than the diameter of the second channel; and / or the bottom end of the first flow channel is covered with a filter screen.

6. The brake disc casting device according to claim 1, characterized in that, The gating system is connected to the middle of the cavity; the second flow channel is disposed at the top of the lower sand mold; the second flow channel includes a pouring socket and at least three transverse flow channels, the pouring socket opening faces upward and is connected to the bottom end of the first flow channel, one end of the plurality of transverse flow channels is connected to the pouring socket at intervals, and the other end of the transverse flow channels extends horizontally in a direction away from the pouring socket and is connected to the cavity.

7. The brake disc casting device according to claim 6, characterized in that, The transverse flow channels include four, which are arranged in a cross shape along the circumferential array of the casting cavity; and / or the first flow channel includes a pouring cup and a straight channel connected sequentially from top to bottom, the transverse cross-sectional area of ​​the straight channel being 1.4 to 1.7 times the sum of the vertical cross-sectional areas of all the transverse flow channels; and / or the depth of the casting cavity is greater than the depth of the transverse flow channels; the inner bottom surface of the casting cavity and the inner bottom surface of the transverse flow channels are smoothly transitioned with rounded corners; and / or the depth of the transverse flow channels is 3 mm to 5 mm.

8. The brake disc casting device according to claim 6, characterized in that, The upper sand mold is provided with a plurality of vertically penetrating vent pins at intervals. The vent pins are internally open and communicate with the cavity and / or the overflow groove.

9. The brake disc casting device according to claim 8, characterized in that, The venting needle is positioned offset from the liquid outlet of the gating system; at least one venting needle is provided between two adjacent transverse flow channels.

10. The brake disc casting device according to claim 1 or 3, characterized in that, The lower sand mold has an annular placement cavity at its top. The outer annular wall of the placement cavity forms the outer periphery of the mold cavity, and the inner annular wall of the placement cavity forms the inner periphery of the mold cavity. The shielding structure includes a sand core disposed within the mold cavity, with its top side shielding a portion of the opening of an overflow groove. The sand core includes a partition and an outer connecting block surrounding the outer periphery of the partition. The partition is annular, and its inner annular periphery is spaced apart from the inner annular wall of the placement cavity. The partition is positioned relative to the upper sand mold and the lower sand mold. The molds are spaced apart, and the partition plate is provided with a plurality of air duct through holes at intervals. The outer peripheral wall of the outer connecting block is attached to the outer ring wall of the placement cavity. The bottom surface of the outer connecting block protrudes downward relative to the bottom surface of the partition plate and extends to the lower sand mold. The top surface of the outer connecting block protrudes upward relative to the top surface of the partition plate and extends to the upper sand mold. The overflow groove is an external overflow groove, which is connected to the top outer periphery of the cavity. The top of the outer connecting block covers the external overflow groove on a circumferential side away from the center of the cavity.

Images