A mold for a chassis for installing an electric power device of a new energy vehicle
By designing a mold with multi-point collaborative feeding, the problems of uneven performance of aluminum alloy profiles and melt flow rate control were solved, thereby improving the stability and safety of battery trays and chassis for new energy vehicles.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- GUANGDONG XINHE ALUMINIUM XINXING CO LTD
- Filing Date
- 2026-01-27
- Publication Date
- 2026-05-29
AI Technical Summary
In the production process of battery trays and chassis for new energy vehicles, the uneven performance of aluminum alloy profiles and the difficulty in controlling the melt flow rate during extrusion result in insufficient stability and safety of the power battery pack.
The mold design employs multi-point collaborative feeding, and precisely controls the melt flow rate through hole structure and flow restriction structure. Combined with sink bridge and slow flow channel structure, it achieves uniform distribution of melt in the mold and control of extrusion rate.
It improves the performance uniformity of wide, thin-walled, and complex cross-section profiles, and enhances the stability and safety of the chassis in supporting the power battery pack.
Smart Images
Figure CN122099094A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the technical field of installation accessories for electric power units in new energy vehicles, and specifically relates to a mold for a chassis for installing electric power units in new energy vehicles. Background Technology
[0002] New energy vehicle components such as the body, subframe, engine, front suspension, front bumper, trunk, and door panels can all be made of aluminum alloy. In the installation process, represented by the power battery pack, aluminum alloy profiles can be used to make the chassis or achieve a lightweight structure and high support strength for the entire power compartment. In addition, aluminum alloy has good thermal conductivity, thus keeping the efficiency of heat dissipation from the power battery pack within a controllable range.
[0003] Components such as battery trays and chassis for new energy vehicles have stringent requirements for the uniformity and stability of performance of wide, thin-walled, and complex-section extruded materials. However, in actual production, aluminum alloy profiles are affected by factors such as uneven composition of alloy castings, uneven temperature and extrusion rate during extrusion, and uneven cooling rate, all of which can lead to significant differences and fluctuations in the longitudinal and cross-sectional properties of wide, thin-walled, and complex-section extruded materials.
[0004] When battery trays and chassis are installed in the battery compartment of new energy vehicles, the performance of the wide, thin-walled, and complex cross-section extruded material determines the stability and safety of the power battery pack. Traditional molds only guide the aluminum alloy melt into holes at different positions. On the one hand, each hole is relatively independent, which makes it difficult for the melt to disperse smoothly in the welding chamber and merge with each other. On the other hand, after the material is fed into the hole, there is a lack of limiting measures near the extrusion hole, which makes it difficult to control the melt flow rate in the narrow area from the outlet, affecting the uniformity of forming and making it difficult to enhance the stability and safety of the chassis in supporting the power battery pack. Summary of the Invention
[0005] The purpose of this invention is to provide a mold for a chassis for installing electric power units in new energy vehicles. This mold can fully diffuse the melt through multi-point coordinated feeding and precisely control its flow rate using a flow-limiting structure. This improves the uniformity of the extrusion performance of wide, thin-walled, and complex cross-section profiles, and ultimately enhances the stability and safety of the chassis made from this profile for supporting the power battery pack.
[0006] The specific technical solution adopted by this invention is as follows: A mold for mounting a chassis of an electric power unit for a new energy vehicle includes a first mold base and a second mold base, and further includes: A hole structure is formed in the first mold base; A working belt is formed on the second mold base. The working belt is integrally provided with a first groove and a second groove. The inner wall of the second mold base is provided with a first rear empty groove, a second rear empty groove and a third rear empty groove that surround the working belt in sequence. During operation, the melt is dispersed into the first mold base and the second mold base through the hole structure. The inner side of the hole structure, the first rear empty groove, the second rear empty groove and the third rear empty groove guide the melt and limit the flow rate of the melt through the working zone, the first groove and the second groove.
[0007] As an optional solution, the hole structure includes a first feed hole, a second feed hole, a third feed hole, a fourth feed hole and a fifth feed hole spaced apart on the first mold base; The first feed hole, the second feed hole, the third feed hole, the fourth feed hole and the fifth feed hole are arranged sequentially along the center line of the working zone to guide the melt across the first rear empty slot, the second rear empty slot and the third rear empty slot.
[0008] As an alternative, a first underbridge is provided between the first feed hole and the second feed hole, and the first underbridge portion is projected onto the area of the first groove near one end of the working belt; The first pressure relief bridge is provided on both sides of the first submerged bridge, and the first flow trough is provided in the middle of the first submerged bridge.
[0009] As an alternative, the first flow-retarding channel is in the shape of a "V" with its opening facing the second feed hole. The end of the "V" shape of the first flow-retarding channel is used to restrict part of the melt from flowing from the first feed hole to the second feed hole, so that the melt diffuses toward one end of the working zone. The inclination angles of the two first pressure-reducing bridges are 15° and 18°, respectively.
[0010] As an alternative, a second submerged bridge is provided between the second feed hole and the third feed hole, and the second submerged bridge portion is projected at two-thirds of the first groove; The second pressure relief bridge is provided on both sides of the second bridge, and a second flow trough is provided in the middle of the second pressure relief bridge.
[0011] As an alternative, the second slow-flow channel is a straight line with flared ends, and the flared area of the second slow-flow channel is used for melt exchange between the second feed port and the third feed port; The inclination angles of the two second pressure-reducing bridges are 13° and 20°, respectively.
[0012] As an alternative, a third underbridge is provided between the third feed hole and the fourth feed hole, and the third underbridge portion is projected onto the area in the middle of the working belt near the first groove; The third sink bridge has a third pressure relief bridge on both sides, and a third flow trough is provided in the middle of the third sink bridge.
[0013] As an alternative, the third flow channel is in the shape of a "V" with its opening facing the third feed hole. The end of the "V" shape of the third flow channel is used to restrict part of the melt from flowing into the third feed hole, so that the melt diffuses toward the area of the working zone located between the first groove and the second groove. The inclination angles of the two third pressure-reducing bridges are 13° and 20°, respectively.
[0014] As an alternative, a fourth underbridge is provided between the fourth feed hole and the fifth feed hole, and the fourth underbridge portion is projected onto the area in the middle of the working belt near the second groove; The fourth sink bridge has a fourth pressure relief bridge on both sides, and a fourth flow trough is provided in the middle of the fourth sink bridge.
[0015] As an alternative, the fourth flow channel is U-shaped with its opening facing the fourth feed hole. The bottom of the U-shape of the fourth flow channel is used to restrict part of the melt from flowing into the fourth feed hole from the fifth feed hole, so that the melt diffuses toward the end of the working zone away from the first groove. The inclination angles of the two fourth pressure-reducing bridges are 16° and 17°, respectively.
[0016] The technical effects achieved by this invention are as follows: This invention provides coordinated feeding from different points, using a bridge structure in conjunction with a rear hollow groove structure to guide the melt flow, thereby limiting the flow rate of the melt through the working zone. At the same time, the slow-flow groove structure provides some obstruction to the melt flowing out of the perforated structure, spreading and limiting the melt to control the melt extrusion rate. This achieves performance improvement for wide-width, thin-walled, and complex cross-section extruded materials, thereby enhancing the stability and safety of the chassis mounted on the power battery pack. Attached Figure Description
[0017] Figure 1 This is a perspective view of the mating surfaces of the first mold base and the second mold base of the present invention; Figure 2 This is a partial cross-sectional view of the hole structure of the present invention; Figure 3 This is a schematic diagram of the working belt structure of the present invention; Figure 4 This is a schematic diagram of the structure of the extruded material of the present invention; Figure 5 This is a cross-sectional view of the screw hole of the present invention; Figure 6 This is a schematic diagram of the inner side of the hole structure of the present invention; Figure 7 This is a partial structural schematic diagram of the first submerged bridge of the present invention; Figure 8 This is a partial structural schematic diagram of the second sunken bridge of the present invention; Figure 9 This is a partial structural schematic diagram of the third submerged bridge of the present invention; Figure 10 This is a partial structural schematic diagram of the fourth submerged bridge of the present invention; Figure 11 This is a cross-sectional view of the mold of the present invention.
[0018] The attached diagram lists the components represented by each number as follows: 1. First mold base; 2. Second mold base; 3. Screw hole; 4. Keyway; 5. Countersunk threaded hole; 6. Pin hole; 7. First feed hole; 8. Second feed hole; 9. Third feed hole; 10. Fourth feed hole; 11. Fifth feed hole; 12. First countersunk bridge; 13. First pressure relief bridge; 14. First slow flow groove; 15. Second countersunk bridge; 16. Second pressure relief bridge; 17. Second slow flow groove; 18. Third countersunk bridge; 19. Third pressure relief bridge; 20. Third slow flow groove; 21. Fourth countersunk bridge; 22. Fourth pressure relief bridge; 23. Fourth slow flow groove; 24. Working zone; 25. First groove; 26. Second groove; 27. First back empty groove; 28. Second back empty groove; 29. Third back empty groove; 30. Heat treatment process hole. Detailed Implementation
[0019] To make the objectives and advantages of this invention clearer, the invention will be specifically described below with reference to embodiments. It should be understood that the following text is merely used to describe one or more specific embodiments of the invention and does not strictly limit the scope of protection specifically claimed by the invention.
[0020] like Figures 1-11 As shown, a mold for mounting a chassis of an electric power unit for a new energy vehicle includes a first mold base 1 and a second mold base 2. During operation, the holes on the first mold base 1 can be aligned with the discharge port of the extruder. The first mold base 1 is then fixed to the extruder by screws passing through countersunk threaded holes 5. Then, as shown... Figure 11 As shown, the second mold base 2 and the first mold base 1 are closed together. The two are aligned by inserting a pin into the pin hole 6 and locked by screwing a bolt into the screw hole 3. The keyway 4 is used to leave a clearance for the bolt to move. After the extruder is started, the melt enters the welding chamber of the mold along the hole structure. Under the limiting action of the flow blocking table and the cylinder, the melt flows to the discharge port of the second mold base 2 to form an extruded material of the preset shape.
[0021] Among them, the flow-blocking platform and the cylinder are used for forming the extruded material. These are technologies well known to those skilled in the art and can be implemented independently by technicians, so they will not be described in detail here.
[0022] See attached document Figure 1 , Figure 3 and Figure 6 In this embodiment, a first feed hole 7, a second feed hole 8, a third feed hole 9, a fourth feed hole 10 and a fifth feed hole 11 are provided on the first mold base 1 as a hole structure for feeding the melt; Meanwhile, the two sets of first feed holes 7, second feed holes 8, third feed holes 9, fourth feed holes 10 and fifth feed holes 11 are arranged alternately on both sides of the center line of the working belt 24 to guide the melt across the welding chamber, while the heat treatment process hole 30 is connected to an external heat transfer medium source to pre-introduce heat transfer medium into the mold for heat preservation of the melt. Since the heat preservation of the mold is a technology well known to those skilled in the art, it will not be described in detail in this embodiment. The heat treatment process holes 30 of the second mold base 2 and the first mold base 1 can be used to allow heat conduction medium to flow separately or in a connected manner.
[0023] like Figure 4 The extruded material shown has circular and triangular holes distributed on it. The melt can be formed by limiting the mold in the first mold base 1. It is finally extruded in the shape of a plate. The thickness of each region of its cross section is different. It needs to be spread out and limited to control the melt extrusion rate, so as to improve the performance of wide, thin-walled, and complex cross-section extruded materials.
[0024] See attached document Figure 1 , Figure 6 and Figure 7 In this embodiment, a first underbridge 12 is provided at the die core between the first feed hole 7 and the second feed hole 8 to slow down the flow of melt in the first feed hole 7 toward the area of the second feed hole 8, so that the first feed hole 7 flows toward the narrower end of the corresponding extruded material as much as possible, and fills the narrow space first. First pressure relief bridges 13 are provided on both sides of the first sink bridge 12, and a first slow flow groove 14 is provided in the middle of the first sink bridge 12. The first pressure relief bridge 13 and the first slow flow groove 14 serve as channels for communication between the first feed hole 7 and the second feed hole 8 after feeding, thereby promoting the welding of the two parts of the molten material.
[0025] See attached document Figure 1 , Figure 6 and Figure 7In order to cause the melt in the second feed hole 8 to flow towards the area of the first feed hole 7, the first slow flow channel 14 in this embodiment is a "V" shape with its opening facing the second feed hole 8. Since the feed area at the opening of the "V" shape is larger than the feed area at its end, the end of the "V" shape of the first slow flow channel 14 is used to restrict part of the melt from flowing from the first feed hole 7 to the second feed hole 8, so that the melt diffuses towards one end of the working zone 24. The two first pressure-reducing bridges 13 have inclination angles of 15° and 18°, respectively. The first pressure-reducing bridge 13 with an inclination angle of 15° is located at the edge of the second feed hole 8, while the first pressure-reducing bridge 13 with an inclination angle of 18° is located at the edge of the first feed hole 7. This makes the pressure-reducing space at the edge of the first feed hole 7 greater than the pressure-reducing space at the edge of the second feed hole 8. As a result, the melt in the second feed hole 8 overflows before the melt in the first feed hole 7, thereby achieving control of the melt extrusion rate at a specified point.
[0026] See attached document Figure 1 , Figure 6 and Figure 8 In this embodiment, the cross-sectional area of the second feed hole 8 is larger than that of the third feed hole 9, so that the second feed hole 8 has enough melt to fill the thicker area of the extruded material. A second bridge 15 is provided between the second feed hole 8 and the third feed hole 9. The second bridge 15 is used to slow down the melt flowing from the third feed hole 9 to the second feed hole 8, so that the melt in the third feed hole 9 preferentially flows to the narrower area in the middle of the corresponding extruded material. Meanwhile, a second pressure-reducing bridge 16 is provided on both sides of the second sinking bridge 15, and a second slow-flow groove 17 is provided in the middle of the second pressure-reducing bridge 16. The second pressure-reducing bridge 16 and the second slow-flow groove 17 serve as channels for communication after the second feed hole 8 and the third feed hole 9 are fed, thereby promoting the welding of the two parts of the molten material.
[0027] See attached document Figure 1 , Figure 6 and Figure 8 The second slow flow channel 17 is a straight line with flared ends. The flared area of the second slow flow channel 17 is used for melt exchange between the second feed hole 8 and the third feed hole 9, so as to realize the mutual convergence of the two melts in the welding chamber. The two second pressure-reducing bridges 16 have inclination angles of 13° and 20°, respectively. The second pressure-reducing bridge 16 with an inclination angle of 13° is located at the edge of the second feed hole 8, while the second pressure-reducing bridge 16 with an inclination angle of 20° is located at the edge of the third feed hole 9. This makes the pressure-reducing space at the edge of the third feed hole 9 greater than the pressure-reducing space at the edge of the second feed hole 8. As a result, the melt in the second feed hole 8 overflows before the melt in the third feed hole 9, thereby achieving control of the melt extrusion rate at a specified point.
[0028] See attached document Figure 1 , Figure 6 and Figure 9 A third bridge 18 is provided between the third feed hole 9 and the fourth feed hole 10. The third bridge 18 is used to slow down the flow of melt from the fourth feed hole 10 to the third feed hole 9, so that the melt in the fourth feed hole 10 preferentially flows to the narrower area in the middle of the corresponding extruded material. The third pressure relief bridge 19 is provided on both sides of the third sink bridge 18, and the third slow flow groove 20 is provided in the middle of the third sink bridge 18. The third pressure relief bridge 19 and the third slow flow groove 20 serve as channels for communication after the third feed hole 9 and the fourth feed hole 10 are fed, which promotes the welding of the two parts of the melt in the welding chamber.
[0029] See attached document Figure 1 , Figure 6 and Figure 9 The third slow flow channel 20 is in the shape of a "V" with its opening facing the third feed hole 9. The end of the "V" shape of the third slow flow channel 20 is used to restrict part of the melt from flowing into the third feed hole 9 from the fourth feed hole 10, so that the melt diffuses toward the area of the working zone 24 located between the first groove 25 and the second groove 26. The two third pressure-reducing bridges 19 have inclination angles of 13° and 20°, respectively. The third pressure-reducing bridge 19 with an inclination angle of 13° is located at the edge of the fourth feed hole 10, while the third pressure-reducing bridge 19 with an inclination angle of 20° is located at the edge of the third feed hole 9. This makes the pressure-reducing space at the edge of the fourth feed hole 10 larger than that at the edge of the third feed hole 9. As a result, the melt in the third feed hole 9 overflows before the melt in the fourth feed hole 10, thereby controlling the melt extrusion rate at a specified point. The melt at this point is preferentially distributed to the connection between the narrower and wider areas in the middle of the extruded material, which can fill the complex connection.
[0030] See attached document Figure 1 , Figure 6 and Figure 10 A fourth bridge 21 is provided between the fourth feed hole 10 and the fifth feed hole 11. The fourth bridge 21 is used to slow down the flow of melt from the fifth feed hole 11 to the fourth feed hole 10, so that the melt in the fifth feed hole 11 preferably flows to the narrower area at the other end of the corresponding extruded material. Meanwhile, a fourth pressure-reducing bridge 22 is provided on both sides of the fourth sinking bridge 21, and a fourth slow-flow groove 23 is provided in the middle of the fourth sinking bridge 21. The fourth pressure-reducing bridge 22 and the fourth slow-flow groove 23 serve as channels for communication after the fourth feed hole 10 and the fifth feed hole 11 are fed, promoting the welding of the two parts of the melt in the welding chamber.
[0031] See attached document Figure 1 , Figure 6 and Figure 10The fourth slow flow channel 23 is U-shaped with its opening facing the fourth feed hole 10. The bottom of the U-shape of the fourth slow flow channel 23 is used to restrict part of the melt from flowing into the fourth feed hole 10, so that the melt diffuses toward the end of the working zone 24 away from the first groove 25. The two fourth pressure-reducing bridges 22 have inclination angles of 16° and 17°, respectively. The fourth pressure-reducing bridge 22 with an inclination angle of 16° is located at the edge of the fourth feed hole 10, while the fourth pressure-reducing bridge 22 with an inclination angle of 17° is located at the edge of the fifth feed hole 11. This makes the pressure-reducing space at the edge of the fifth feed hole 11 larger than that at the edge of the fourth feed hole 10. As a result, the melt in the fourth feed hole 10 overflows before the melt in the fifth feed hole 11, thereby controlling the extrusion rate of the melt at a specified point. The melt at this point is preferentially distributed to the narrower area at the other end of the extruded material, which can fill the complex end.
[0032] See attached document Figure 1 , Figure 3 and Figure 4 As the melt is further extruded, the melt needs to leave the welding chamber and be extruded from the working belt 24 of the second die holder 2 until it is formed. The working belt 24 is integrally provided with a first groove 25 and a second groove 26. The first groove 25 and the second groove 26 are used for forming the thicker area of the extruded material. The first undercut 12 is partially projected onto the area of the first groove 25 near one end of the working belt 24, the second undercut 15 is partially projected onto two-thirds of the area of the first groove 25, the third undercut 18 is partially projected onto the area of the middle of the working belt 24 near the first groove 25, and the fourth undercut 21 is partially projected onto the area of the middle of the working belt 24 near the second groove 26, in order to limit the extrusion rate of the melt in the welding chamber. The inner wall of the second die holder 2 is provided with a first rear empty groove 27, a second rear empty groove 28 and a third rear empty groove 29 that surround the working belt 24 in sequence. During operation, the melt is dispersed through the perforated structure into the welding chambers inside the first mold base 1 and the second mold base 2, and spans the first rear cavity 27, the second rear cavity 28, and the third rear cavity 29. The melt is guided by the first sinker bridge 12, the second sinker bridge 15, the third sinker bridge 18, and the fourth sinker bridge 21 in conjunction with the first rear cavity 27, the second rear cavity 28, and the third rear cavity 29. This is used to limit the flow rate of the melt through the working zone 24, the first groove 25, and the second groove 26, thereby spreading and limiting the melt to control the extrusion rate. This improves the performance of wide-width, thin-walled, and complex cross-section extruded materials, thereby enhancing the stability and safety of the chassis mounted on the power battery pack.
[0033] The working principle of this invention is as follows: When the mold is installed in the extruder, the first feed hole 7, the second feed hole 8, the third feed hole 9, the fourth feed hole 10 and the fifth feed hole 11 serve as feed holes. The melt is guided by the first sinker 12, the second sinker 15, the third sinker 18 and the fourth sinker 21 and diffuses along the length of the working belt 24.
[0034] Meanwhile, the first pressure-reducing bridge 13, the second pressure-reducing bridge 16, the third pressure-reducing bridge 19, and the fourth pressure-reducing bridge 22 with inclination angles respectively limit the melt flowing out of the first feed hole 7, the second feed hole 8, the third feed hole 9, the fourth feed hole 10, and the fifth feed hole 11, while the first slow flow channel 14, the second slow flow channel 17, the third slow flow channel 20, and the fourth slow flow channel 23 play a role in obstructing the flow of melt across the holes, so as to control the melt extrusion rate.
[0035] Finally, the melt leaves the welding chamber and is extruded from the working belt 24.
[0036] The above description is merely an optional embodiment of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention. Structures, devices, and operating methods not specifically described or explained in this invention, unless otherwise specified or limited, shall be implemented according to conventional means in the art.
Claims
1. A mold for mounting a chassis of an electric power unit for a new energy vehicle, comprising a first mold base (1) and a second mold base (2), characterized in that, Also includes: A hole structure is formed in the first mold base (1); The working belt (24) is opened on the second mold base (2). The working belt (24) is integrally provided with a first groove (25) and a second groove (26). The inner wall of the second mold base (2) is provided with a first rear empty groove (27), a second rear empty groove (28) and a third rear empty groove (29) that surround the working belt (24) in sequence. During operation, the melt is dispersed into the first mold base (1) and the second mold base (2) through the hole structure. The inner side of the hole structure, the first rear empty groove (27), the second rear empty groove (28) and the third rear empty groove (29) guide the melt and limit the flow rate of the melt through the working zone (24), the first groove (25) and the second groove (26).
2. The mold for the chassis according to claim 1, characterized in that: The hole structure includes a first feed hole (7), a second feed hole (8), a third feed hole (9), a fourth feed hole (10) and a fifth feed hole (11) spaced apart on the first mold base (1). The first feed hole (7), the second feed hole (8), the third feed hole (9), the fourth feed hole (10) and the fifth feed hole (11) are arranged sequentially along the center line of the working zone (24) to guide the melt across the first back empty slot (27), the second back empty slot (28) and the third back empty slot (29).
3. The mold for the chassis according to claim 2, characterized in that: A first sinker (12) is provided between the first feed hole (7) and the second feed hole (8), and the first sinker (12) is partially projected onto the area of the first groove (25) near one end of the working belt (24); The first sinking bridge (12) has a first pressure relief bridge (13) on both sides, and a first slow flow channel (14) is provided in the middle of the first sinking bridge (12).
4. The mold for the chassis according to claim 3, characterized in that: The first slow flow channel (14) is in the shape of a "V" with its opening facing the second feed hole (8). The end of the "V" shape of the first slow flow channel (14) is used to restrict part of the melt from flowing from the first feed hole (7) to the second feed hole (8), so that the melt diffuses toward one end of the working belt (24). The inclination angles of the two first pressure-reducing bridges (13) are 15° and 18°, respectively.
5. The mold for the chassis according to claim 2, characterized in that: A second sinker (15) is provided between the second feed hole (8) and the third feed hole (9), and the second sinker (15) is partially projected onto two-thirds of the first groove (25); The second sinking bridge (15) has a second pressure relief bridge (16) on both sides, and a second slow flow channel (17) is provided in the middle of the second pressure relief bridge (16).
6. The mold for the chassis according to claim 5, characterized in that: The second slow-flow channel (17) is a straight line with two flared ends. The flared area of the second slow-flow channel (17) is used for melt exchange between the second feed hole (8) and the third feed hole (9). The inclination angles of the two second pressure-reducing bridges (16) are 13° and 20°, respectively.
7. The mold for the chassis according to claim 2, characterized in that: A third sinker (18) is provided between the third feed hole (9) and the fourth feed hole (10), and the third sinker (18) is partially projected into the area of the middle of the working belt (24) near the first groove (25); The third sink bridge (18) has a third pressure relief bridge (19) on both sides, and a third slow flow channel (20) is provided in the middle of the third sink bridge (18).
8. The mold for the chassis according to claim 7, characterized in that: The third slow-flow groove (20) is in the shape of a "V" with its opening facing the third feed hole (9). The end of the "V" shape of the third slow-flow groove (20) is used to restrict part of the melt from flowing into the third feed hole (9) through the fourth feed hole (10), so that the melt diffuses toward the area of the working zone (24) between the first groove (25) and the second groove (26). The inclination angles of the two third pressure-reducing bridges (19) are 13° and 20°, respectively.
9. The mold for the chassis according to claim 2, characterized in that: A fourth sinker (21) is provided between the fourth feed hole (10) and the fifth feed hole (11), and the fourth sinker (21) is partially projected into the area of the middle of the working belt (24) near the second groove (26); The fourth sink bridge (21) has a fourth pressure relief bridge (22) on both sides, and a fourth slow flow channel (23) is provided in the middle of the fourth sink bridge (21).
10. The mold for the chassis according to claim 9, characterized in that: The fourth slow flow groove (23) is U-shaped with its opening facing the fourth feed hole (10). The bottom of the U-shape of the fourth slow flow groove (23) is used to restrict part of the melt from flowing into the fourth feed hole (10) through the fifth feed hole (11), so that the melt diffuses toward the working belt (24) away from the first groove (25). The inclination angles of the two fourth pressure-reducing bridges (22) are 16° and 17°, respectively.