Brake drum casting mold

Abstract

The utility model provides a brake drum casting die which comprises an upper die and a lower die, and after the upper die is assembled on the lower die, a casting cavity used for casting a brake drum is defined by the upper die and the lower die. The casting cavity comprises a body cavity, a flange cavity arranged at the bottom of the body cavity and a reinforcing band cavity arranged at the top of the body cavity. The upper die is provided with a riser groove and a casting runner, the riser groove is communicated with the reinforcing band cavity, the casting runner extends downwards, and the lower end of the casting runner is communicated with the bottom of the casting cavity. In the cold contraction process of a molten metal solution for casting the brake drum, the molten liquid in the riser groove automatically feeds the reinforcing band under the action of self weight, and the molten liquid in the casting runner automatically feeds the flange, so that the quality of the brake drum at the reinforcing band and the flange is ensured, the quality of the brake drum is improved, and the service life of the brake drum is prolonged. And the height of the brake drum casting mold can be reduced, so that the cost of the brake drum casting mold is reduced.

Description

Technical Field

[0001] This utility model relates to the field of casting technology, and in particular to a brake drum casting mold. Background Technology

[0002] Commercial vehicle brake drums are essential components in automobile manufacturing, with high market demand. They are also susceptible to damage and are crucial safety parts for vehicles, significantly impacting driving safety. Currently, various manufacturing methods exist for brake drums, but existing methods often result in poor internal flange quality and shrinkage, which can easily lead to the brake drum bottoming out, cracking, and ultimately, brake drum failure. Utility Model Content

[0003] The purpose of this invention is to solve the problem that the existing methods of manufacturing brake drum castings easily lead to poor internal quality of the flange.

[0004] To solve the above-mentioned technical problems, this utility model provides a brake drum casting mold, including an upper mold and a lower mold. The upper mold and the lower mold together form a casting cavity for casting a brake drum. The casting cavity includes a body cavity, a flange cavity, and a reinforcing strip cavity. The flange cavity is located at the bottom of the body cavity and communicates with the body cavity. The reinforcing strip cavity is located at the top of the body cavity and communicates with the body cavity. The upper mold is provided with a riser groove and a casting channel. The riser groove communicates with the reinforcing strip cavity. The casting channel extends downward, and its lower end communicates with the bottom of the casting cavity.

[0005] In some embodiments of this application, the circumferential outer side of the flange cavity is connected to the body cavity; the casting channel is connected to the side of the flange cavity away from the body cavity.

[0006] In some embodiments of this application, the casting runner includes a vertically arranged sprue and a horizontally arranged ingate. The sprue is located in the middle of the upper mold and extends vertically through the upper mold. The ingate is disposed on the bottom surface of the upper mold. One end of the ingate is connected to the sprue, and the other end is connected to the end of the flange cavity away from the body cavity. The cross-sectional area of ​​the ingate is smaller than that of the sprue.

[0007] In some embodiments of this application, the casting runner further includes a horizontally arranged transverse runner, which is disposed on the bottom surface of the upper mold. One end of the transverse runner is connected to the sprue, and the other end is connected to the ingate. The cross-sectional area of ​​the transverse runner is larger than the cross-sectional area of ​​the ingate and smaller than the cross-sectional area of ​​the sprue.

[0008] In some embodiments of this application, the casting runner further includes a first filter runner and a second filter runner. The first filter runner is disposed on the bottom surface of the upper mold and is located below the sprue. The second filter runner is disposed on the bottom surface of the groove of the lower mold and is located below the first filter runner. The second filter runner connects the first filter runner and the sprue.

[0009] In some embodiments of this application, the top surface of the lower mold is provided with a groove; the bottom surface of the upper mold is provided with a boss that protrudes downwards, the boss is inserted into the groove, and the outer wall surface of the boss and the inner wall surface of the groove together form the casting cavity; the riser groove is provided on the radially outer side of the boss, and the riser groove communicates with the outer side of the casting cavity; the sprue is provided on the top surface of the upper mold and passes through the boss; the ingate, the runner and the first filter runner are all provided on the bottom surface of the boss.

[0010] In some embodiments of this application, the upper mold is further provided with an exhaust hole, which connects the reinforcing strip cavity and the outer surface of the upper mold; the brake drum casting mold further includes an exhaust structure, which includes a drive member and an exhaust pin, the exhaust pin is inserted into the exhaust hole and can slide along the axial direction of the exhaust hole, the drive member is mounted on the upper mold and connected to the exhaust pin, and the drive member is used to drive the exhaust pin to be pulled out or inserted into the exhaust hole.

[0011] In some embodiments of this application, the riser groove is located on the side where the casting cavity communicates with the casting channel; the venting pin is vertically arranged; the venting pin is arranged on the side opposite to the riser groove.

[0012] In some embodiments of this application, the top of the riser groove is positioned higher than the position of the reinforcing strip cavity.

[0013] In some embodiments of this application, the lower mold is a wet sand mold; the upper mold is a wet sand mold.

[0014] As can be seen from the above technical solution, the beneficial effects of this utility model are as follows:

[0015] The brake drum casting mold of this application includes an upper mold and a lower mold. After the upper mold is assembled onto the lower mold, the upper and lower molds together form a casting cavity for casting the brake drum. The casting cavity includes a body cavity, a flange cavity located at the bottom of the body cavity, and a reinforcing strip cavity located at the top of the body cavity. The upper mold is provided with riser grooves and a casting channel. The riser grooves are connected to the reinforcing strip cavity, and the casting channel extends downwards, with its lower end connected to the bottom of the casting cavity. During the cooling and shrinking process of the molten metal solution used to cast the brake drum, the molten metal in the riser grooves automatically feeds the reinforcing strip under its own weight, and the molten metal in the casting channel automatically feeds the flange, ensuring the quality of the brake drum at the reinforcing strip and flange, thereby improving the quality of the brake drum. Furthermore, by automatically feeding the flange with the molten material in the casting channel, the volume and height required for the riser groove are reduced, which helps to reduce the volume of the brake drum casting mold. Moreover, the casting channel extends downward and connects to the bottom of the casting cavity at its lower end, thereby reducing the height of the brake drum casting mold while ensuring the length of the casting channel, thus reducing the cost of the brake drum casting mold. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the brake drum in one embodiment.

[0017] Figure 2 This is a cross-sectional structural schematic diagram of the brake drum casting mold in one embodiment.

[0018] Figure 3 This is a schematic diagram of the lower mold structure in one embodiment.

[0019] Figure 4 This is a schematic diagram of the upper mold in one embodiment.

[0020] Figure 5 This is a cross-sectional view of the upper mold in one embodiment.

[0021] Figure 6 This is a schematic diagram of the casting flow channel arrangement in one embodiment.

[0022] The reference numerals in the attached drawings are explained as follows: 1-Lower mold; 11-Groove; 12-Second filter runner; 13-Protruding ring; 2-Upper mold; 21-Boss; 22-First annular groove; 23-Second annular groove; 24-Riser groove; 25-Casting runner; 251-Sprue; 252-Grunt; 253-Instrument; 254-First filter runner; 26-Vent hole; 3-Ventilation structure; 31-Drive component; 32-Ventilation pin; 4-Casting cavity; 41-Body cavity; 42-Flange cavity; 43-Reinforcing strip cavity; 100-Brake drum; 101-Body; 102-Flange; 103-Reinforcing strip. Detailed Implementation

[0023] Typical embodiments embodying the features and advantages of this utility model will be described in detail in the following description. It should be understood that this utility model can have various variations in different embodiments, all of which do not depart from the scope of this utility model, and the descriptions and illustrations therein are for illustrative purposes only and not intended to limit this utility model.

[0024] In the description of this application, it should be understood that, in the embodiments shown in the accompanying drawings, the indications of direction or positional relationships (such as up, down, left, right, front, and back) are merely for the convenience of describing this application 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. These descriptions are appropriate when these elements are in the positions shown in the accompanying drawings. If the description of the positions of these elements changes, these directional indications also change accordingly.

[0025] Furthermore, the terms "first" and "second" 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. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this application, "a plurality of" means two or more, unless otherwise explicitly specified.

[0026] See Figure 1 The brake drum 100 includes a body 101 and flanges 102 and reinforcing strips 103 respectively disposed at both axial ends of the body 101. The radially outer side of the flanges 102 is connected to the body 101, and the reinforcing strips 103 are disposed on the outer side of the body 101 away from the flanges 102. Existing manufacturing methods for brake drums 100 typically involve molten metal entering the casting cavity from the upper end of the mold. This method easily leads to poor internal quality of the flanges 102 or reinforcing strips 103 formed at the bottom of the casting cavity, resulting in shrinkage porosity, which can easily cause the brake drum 100 to crack and fail, especially with ordinary clay sand production processes. This application addresses the problem of poor internal quality of the flanges 102 easily caused by existing methods of manufacturing brake drum 100 castings by providing a brake drum casting mold.

[0027] See Figure 2The brake drum casting mold of this application includes an upper mold 2 and a lower mold 1, which are fitted together. After the upper mold 2 is assembled onto the lower mold 1, the upper mold 2 and the lower mold 1 together form a casting cavity 4 for casting the brake drum 100. The casting cavity 4 includes a body cavity 41, a flange cavity 42 disposed at the bottom of the body cavity 41, and a reinforcing strip cavity 43 disposed at the top of the body cavity 41. The body cavity 41 is used to form the body 101 of the brake drum 100, the flange cavity 42 is used to form the flange 102 of the brake drum 100, and the reinforcing strip cavity 43 is used to form the reinforcing strip 103 of the brake drum 100. The outer circumferential side of the flange cavity 42 communicates with the body cavity 41. The casting flow channel 25 communicates with the side of the flange cavity 42 away from the body cavity 41.

[0028] See Figure 3 Specifically, the top surface of the lower mold 1 has a groove 11; the cross-section of the groove 11 is circular and matches the outer diameter of the body 101. A second filter runner 12 is provided at the bottom of the groove 11, and the top surface of the second filter runner 12 is open. A raised ring 13 is provided on the top surface of the lower mold 1 along the edge of the groove 11. The raised ring 13 extends above the lower mold 1, and the outer diameter of the raised ring 13 matches the outer diameter of the reinforcing strip 103.

[0029] See Figure 4 and Figure 5 The upper mold 2 has a boss 21 protruding downwards from its bottom surface. The cross-section of the boss 21 is circular and matches the inner diameter of the body 101. A first annular groove 22 is provided on the bottom surface of the boss 21. The bottom surface and circumferential outer surface of the first annular groove 22 are open. The inner diameter of the first annular groove 22 is equal to the inner diameter of the flange 102. A second annular groove 23 is provided on the outer circumferential side of the boss 21. The depth direction of the second annular groove 23 is the same as the axial direction of the boss 21 and opposite to the direction of its protrusion. The outer diameter of the second annular groove 23 is equal to the outer diameter of the reinforcing strip 103. A riser groove 24 is provided on one side of the second annular groove 23. The riser groove 24 communicates with the second annular groove 23, and its bottom surface is open.

[0030] See Figure 2After the upper mold 2 is assembled onto the lower mold 1, the boss 21 is inserted into the groove 11, and the outer wall of the boss 21 and the inner wall of the groove 11 enclose and form a casting cavity 4. Furthermore, a body cavity 41 is formed between the circumferential outer wall of the boss 21 and the circumferential inner wall of the groove 11, forming the body 101 for forming the brake drum 100. A flange cavity 42 is formed at the first annular groove 22, and the outer circumferential side of the flange cavity 42 communicates with the body cavity 41. The flange cavity 42 is used to form the flange 102 of the brake drum 100. The convex ring 13 blocks the opening of the second annular groove 23, and a reinforcing strip cavity 43 is formed inside the second annular groove 23, forming the reinforcing strip 103 of the brake drum 100. The opening of the riser groove 24 is blocked by the top surface of the lower mold 1, so that the riser groove 24 forms a closed cavity that only communicates with the reinforcing strip cavity 43.

[0031] The top of the riser groove 24 is higher than the position of the reinforcing strip cavity 43. This allows the molten metal in the riser groove 24 to automatically flow back into the reinforcing strip cavity 43 under its own gravity to compensate for the shrinkage when the molten metal in the reinforcing strip cavity 43 shrinks, thus improving the quality of the reinforcing strip 103. Similarly, when the molten metal in the body cavity 41 shrinks, the molten metal in the riser groove 24 can also automatically flow through the reinforcing strip cavity 43 under its own gravity to compensate for the shrinkage of the molten metal in the body cavity 41.

[0032] exist Figure 2 In the illustrated embodiment, the riser groove 24 communicates with the reinforcing strip cavity 43 at its midpoint in the height direction. That is, the top surface of the convex ring 13 is located at the midpoint of the riser groove 24, so that after the convex ring 13 blocks the opening of the second annular groove 23, a structure is formed in which the midpoint of the riser groove 24 communicates with the reinforcing strip cavity 43. During the casting of the brake drum 100, the molten metal solution sequentially enters the flange cavity 42, body cavity 41, reinforcing strip cavity 43, and riser groove 24 from the casting channel 25. The leading edge of the molten metal solution pushes impurities in the flange cavity 42, body cavity 41, and reinforcing strip cavity 43 into the riser groove 24 and settles to the bottom of the riser groove 24, while the gas, due to its smaller weight, remains at the top of the riser groove 24. The molten metal solution used for feeding that flows back from the riser groove 24 to the reinforcing zone cavity 43 is the molten metal solution in the middle of the riser groove 24. The molten metal solution in the middle of the riser groove 24 does not contain impurities and gas, thereby improving the quality of the formed reinforcing zone 103.

[0033] See Figure 5 and Figure 6The casting runner 25 extends downward from the top surface of the upper mold 2, and its lower end connects to the bottom of the casting cavity 4. This allows the molten metal in the flange cavity 42 to automatically replenish the molten metal in the flange cavity 42 under gravity when the molten metal in the casting runner 25 cools and contracts, thereby improving the quality of the flange 102. Furthermore, the molten metal in the lower end of the casting runner 25 and the molten metal in the riser groove 24 replenish different positions of the brake drum 100, shortening the flow distance of the molten metal required for replenishment and accelerating the replenishment speed. This allows the riser groove 24 to be set as a standard riser instead of a heating riser, thus reducing costs and simplifying the structure.

[0034] exist Figure 5 In the illustrated embodiment, the casting channel 25 is connected to the side of the flange cavity 42 away from the body cavity 41. This allows the molten metal solution to expel gas from the flange cavity 42 from the body cavity 41, the reinforcing strip cavity 43, to the riser groove 24, or from the vent hole 26 described below when the molten metal enters the flange cavity 42. This prevents gas from being trapped in the flange cavity 42, which could lead to porosity in the formed flange 102 and affect the quality of the brake drum 100. It should be noted that the casting channel 25 can also be connected to the lower end of the body cavity 41.

[0035] The casting runner 25 includes a vertically arranged sprue 251, a horizontally arranged runner 252, a horizontally arranged ingate 253, a first filter runner 254, and a second filter runner 12. The sprue 251 is located in the middle of the upper mold 2, that is, the sprue 251 is located at or near the axis of the boss 21, and the sprue 251 vertically penetrates the upper mold 2. The first filter runner 254 is located on the bottom surface of the upper mold 2, below the sprue 251, and communicates with the sprue 251. The runner 252 and the ingate 253 are located on the bottom surface of the boss 21 of the upper mold 2, and the runner 252 and the first filter runner 254 are spaced apart. One end of the ingate 253 is connected to the sprue 251, and the other end is connected to the end of the flange cavity 42 away from the body cavity 41. The second filter runner 12 is located below the first filter runner 254 and is connected to both the first filter runner 254 and the runner 252. This arrangement ensures that the sprue 251, the first filter runner 254, the second filter runner 12, the runner 252, and the ingate 253 are sequentially connected and communicate with the flange cavity 42 of the casting cavity 4, allowing the molten metal to enter the casting cavity 4 through the casting channel 25. The sprue 251 has a larger opening diameter at the top surface of the upper mold 2, forming a sprue opening, which facilitates the entry of the molten metal into the casting channel 25.

[0036] In this design, the second filter runner 12 is positioned on the lower mold 1. The first filter runner 254 and the horizontal runner 252 are spaced apart and connected through the second filter runner 12. This means the second filter runner 12 is not on the same plane as the first filter runner 254 and the horizontal runner 252, thus increasing the resistance of the casting flow channel 25. This causes the molten metal entering the casting cavity 4 from the sprue 251 to first impact the bottom wall of the second filter runner 12, then pass through the horizontal runner 252 and the ingate 253 before entering the casting cavity 4. When the molten metal impacts the bottom wall of the second filter runner 12, it causes slag in the molten metal to float and deposit, improving the quality of the molten metal entering the casting cavity 4, thereby improving the quality of the brake drum 100.

[0037] In one embodiment, the cross-sectional area of ​​the ingate 253 is smaller than that of the sprue 251, and the cross-sectional area of ​​the gating 252 is larger than that of the ingate 253 and smaller than that of the sprue 251. This further increases the resistance of the casting channel 25, realizes the flow rate control and structural closure of the molten metal solution, enhances the slag blocking ability, promotes the slag to float and deposit, and prevents the slag from entering the casting cavity 4. Moreover, it can reduce the intake of gas and impurities in the molten metal into the casting cavity 4, effectively reduce casting defects such as porosity and inclusions, thereby improving the quality of the casting.

[0038] In a preferred embodiment of this application, the ratio of the cross-sectional area of ​​the sprue 251, the cross-sectional area of ​​the gutter 252, and the cross-sectional area of ​​the ingate 253 is (1.4-1.8):(1.3-1.1):1.

[0039] The upper mold 2 has a first groove, a second groove, and a third groove on the bottom surface of the boss 21. The openings of the first groove, the second groove, and the third groove are located on the bottom surface of the boss 21. The first groove is located in the middle of the bottom surface of the boss 21 and communicates with the sprue 251. The second groove is spaced apart from the first groove and located outside the first groove. The third groove is located outside the second groove and communicates with the second groove and the first annular groove 22. The lower mold 1 has a fourth groove at the bottom of the groove 11. After the upper mold 2 is assembled onto the lower mold 1, the fourth groove connects the first groove and the second groove. The lower mold 1 and the upper mold 2 together form a first filter sprue 254 at the first groove, a second filter sprue 12 at the fourth groove, a transverse sprue 252 at the second groove, and an inner sprue 253 at the third groove. The depth of the third groove is less than the depth of the first, second and fourth grooves, which results in a smaller cross-sectional area of ​​the ingate 253.

[0040] exist Figure 4In the illustrated embodiment, multiple ingates 253 are provided, allowing molten metal to enter the casting cavity 4 from the multiple ingates 253 at the bottom of the casting cavity 4. This avoids the problem of gas being trapped inside the casting cavity 4 and forming porosity, thus improving the quality of the brake drum 100. In other embodiments, only one ingate 253 may be provided.

[0041] In one embodiment, the runner 252 is arc-shaped and communicates with multiple ingates 253. The center of the arc of the runner 252 coincides with the central axis of the boss 21, making the distance between the runner 252 and the casting cavity 4 equal, thereby ensuring that each ingate 253 has the same length, which facilitates control of the flow rate of the molten metal entering the casting cavity 4 from each ingate 253. In other embodiments, the runner 252 can be straight; or, multiple runners 252 can be provided, with each runner 252 corresponding to one of the multiple ingates 253.

[0042] It should be noted that the casting runner 25 may not have a horizontal sprue 252, a first filter runner 254, and a second filter runner 12, and the ingate 253 may be directly connected to the sprue 251; or, the casting runner 25 may not have a first filter runner 254 and a second filter runner 12, and the ingate 253 may be connected to the sprue 251 through the horizontal sprue 252; or, the casting runner 25 may not have a horizontal sprue 252, and the ingate 253 may be connected to the second filter runner 12.

[0043] See Figure 5 The upper mold 2 is also provided with an exhaust hole 26, which connects the reinforcing strip cavity 43 and the outer surface of the upper mold 2, so that the gas in the casting cavity 4 can be discharged from the exhaust hole 26, thus avoiding the formation of air holes on the brake drum 100.

[0044] The brake drum casting mold also includes a venting structure 3, which includes a drive member 31 and a venting pin 32. The venting pin 32 is inserted into a venting hole 26 and can slide axially along the venting hole 26. The drive member 31 is mounted on the upper mold 2 and connected to the venting pin 32. The drive member 31 is used to drive the venting pin 32 to be withdrawn or inserted into the venting hole 26. When venting is required, the drive member 31 drives the venting pin 32 to be withdrawn from the venting hole 26, thereby allowing the gas in the casting cavity 4 to be discharged from the venting hole 26. When venting is not required, the drive member 31 drives the venting pin 32 to be inserted into the venting hole 26, thereby preventing the molten metal solution from leaking from the venting hole 26. The drive member 31 is preferably a telescopic cylinder. In other embodiments, the drive member 31 can also be a lead screw structure, a gear and rack structure, etc.

[0045] exist Figure 5In the illustrated embodiment, the axis of the vent hole 26 is parallel to the axis of the boss 21, meaning the vent hole 26 extends in the direction of separation between the upper mold 2 and the lower mold 1 (i.e., the vent pin 32 is vertically positioned). This allows the sprue formed at the vent hole 26 to be removed from the upper mold 2 along with the workpiece during mold opening. In other embodiments, the axis of the vent hole 26 may also be at an angle or perpendicular to the axis of the boss 21, meaning the vent hole 26 may be obliquely or horizontally positioned. When the workpiece is removed from the upper mold 2, the sprue formed at the vent hole 26 first disconnects from the workpiece, and then the vent pin 32 is driven by the drive member 31 to push the sprue out of the vent hole 26.

[0046] The riser groove 24 is located on the side of the casting cavity 4 that connects to the casting runner 25, and the vent hole 26 is located on the side opposite to the riser groove 24. The riser groove 24 can accommodate some gas, and the vent hole 26 can also discharge gas. Positioning the vent hole 26 and the riser groove 24 on both sides of the casting cavity 4 shortens the path for gas to exit the casting cavity 4, improving the efficiency of gas discharge and preventing gas from being trapped inside the casting cavity 4, which could lead to porosity on the workpiece. Multiple vent holes 26 can be spaced out, and the number of vent pins 32 is equal to the number of vent holes 26, with each pin corresponding to a specific vent hole 32. All vent pins 32 can be driven by a single drive element 31, or each vent pin 32 can have a corresponding drive element 31, so that each vent pin 32 is driven by its corresponding drive element 31.

[0047] In one embodiment, the lower mold 1 and the upper mold 2 are uniformly moistened sand molds. These molds offer advantages such as low investment cost and high adaptability, thus enabling the brake drum casting mold to possess multiple advantages, including high production efficiency. It should be noted that the lower mold 1 and the upper mold 2 can also be molds made of other materials.

[0048] In the brake drum casting mold of this application, the upper mold 2 is provided with a riser groove 24 and a casting channel 25. The riser groove 24 is connected to the reinforcing strip cavity 43, and the top of the riser groove 24 is higher than the position of the reinforcing strip cavity 43. The casting channel 25 extends downward, and the lower end of the casting channel 25 is connected to the bottom of the casting cavity 4. When the molten metal solution of the brake drum 100 is cooling and shrinking, the melt in the riser groove 24 automatically feeds the reinforcing strip 103 under its own weight, and the melt in the casting channel 25 automatically feeds the flange 102, ensuring the quality of the brake drum 100 at the reinforcing strip 103 and the flange 102, thereby improving the quality of the brake drum 100. Furthermore, the molten material in the casting channel 25 automatically feeds the flange 102, reducing the volume and height required for the riser groove 24. This helps to reduce the volume of the brake drum casting mold. Moreover, the casting channel 25 extends downward and connects to the bottom of the casting cavity 4 at its lower end. This ensures the length of the casting channel 25 while reducing the height of the brake drum casting mold, thereby lowering the cost of the brake drum casting mold.

[0049] In one embodiment, the brake drum 100 is made of cast iron, meaning the molten metal solution used to cast the brake drum 100 is cast iron melt. The cast iron melt contains molten iron and molten graphite. In the early stage of shrinkage, the molten iron shrinks more than it expands, while in the later stage, the graphite expands more than it shrinks. Therefore, in the early stage of the cooling shrinkage process of the molten metal solution used to cast the brake drum 100, the molten metal in the riser groove 24 automatically feeds the reinforcing strip 103 under its own weight, and the molten metal in the casting channel 25 automatically feeds the flange 102. In the later stage of the cooling shrinkage process of the molten metal solution used to cast the brake drum 100, the expansion of the graphite in the molten metal ensures the dimensional accuracy of the brake drum 100, improves the quality of the brake drum 100, and enhances driving safety. This also increases the yield of the brake drum 100 and reduces production costs.

[0050] Although the present invention has been described with reference to several typical embodiments, it should be understood that the terminology used is descriptive and exemplary, and not restrictive. Since the present invention can be embodied in many forms without departing from the spirit or essence of the invention, it should be understood that the above embodiments are not limited to any of the foregoing details, but should be interpreted broadly within the spirit and scope defined by the appended claims. Therefore, all variations and modifications falling within the scope of the claims or their equivalents should be covered by the appended claims.

Claims

1. A brake drum casting mold characterized by, The device includes an upper mold and a lower mold, which together form a casting cavity for casting a brake drum. The casting cavity includes a body cavity, a flange cavity, and a reinforcing strip cavity. The flange cavity is located at the bottom of the body cavity and communicates with it. The reinforcing strip cavity is located at the top of the body cavity and communicates with it. The upper mold is provided with a riser groove and a casting channel. The riser groove communicates with the reinforcing strip cavity. The casting channel extends downward and its lower end communicates with the bottom of the casting cavity.

2. The brake drum casting mold according to claim 1, characterized in that, The outer circumferential side of the flange cavity is connected to the body cavity; The casting channel is connected to the side of the flange cavity away from the body cavity.

3. The brake drum casting mold according to claim 2, characterized in that, The casting runner includes a vertically arranged sprue and a horizontally arranged ingate. The sprue is located in the middle of the upper mold and penetrates the upper mold vertically. The ingate is located on the bottom surface of the upper mold. One end of the ingate is connected to the sprue, and the other end is connected to the end of the flange cavity away from the body cavity. The cross-sectional area of ​​the ingate is smaller than that of the sprue.

4. The brake drum casting mold according to claim 3, characterized in that, The casting runner also includes a horizontally arranged sprue, which is located on the bottom surface of the upper mold. One end of the sprue is connected to the sprue, and the other end is connected to the ingate. The cross-sectional area of ​​the horizontal runner is larger than the cross-sectional area of ​​the ingate and smaller than the cross-sectional area of ​​the vertical runner.

5. The brake drum casting mold according to claim 4, characterized in that, The casting runner also includes a first filter runner and a second filter runner. The first filter runner is disposed on the bottom surface of the upper mold and is located below the sprue. The second filter runner is disposed on the bottom surface of the groove of the lower mold and is located below the first filter runner. The second filter runner connects the first filter runner and the sprue.

6. The brake drum casting mold according to claim 5, characterized in that, The top surface of the lower mold is provided with a groove; The bottom surface of the upper mold has a protruding boss that protrudes downwards. The boss is inserted into the groove, and the outer wall of the boss and the inner wall of the groove together form the casting cavity. The riser groove is located on the radial outer side of the boss, and the riser groove communicates with the outer side of the casting cavity; The sprue is located on the top surface of the upper mold and extends through the boss; the ingate, the sprue and the first filter sprue are all located on the bottom surface of the boss.

7. The brake drum casting mold according to claim 2, characterized in that, The upper mold is also provided with an exhaust hole, which connects the reinforcing strip cavity and the outer surface of the upper mold; The brake drum casting mold further includes an exhaust structure, which includes a drive component and an exhaust pin. The exhaust pin is inserted into the exhaust hole and can slide along the axial direction of the exhaust hole. The drive component is mounted on the upper mold and connected to the exhaust pin. The drive component is used to drive the exhaust pin to be pulled out or inserted into the exhaust hole.

8. The brake drum casting mold according to claim 7, characterized in that, The riser groove is located on the side where the casting cavity communicates with the casting channel; The venting needle is arranged vertically; the venting needle is located on the side opposite to the riser groove.

9. The brake drum casting mold according to claim 1, characterized in that, The top of the riser groove is higher than the position of the reinforcing strip cavity.

10. The brake drum casting mold according to claim 1, characterized in that, The lower mold is a wet sand mold; The upper mold is a damp sand mold.

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