Double-material brake drum casting centrifugal machine and manufacturing method

Abstract

The invention discloses a double-material brake drum casting centrifugal machine and a manufacturing method, the double-material brake drum casting centrifugal machine comprises an upper die base, a lower die base, a first hydraulic column, an upper die connecting plate, a driving device and an end cover, a guide column is fixed between the upper die base and the lower die base, and the first hydraulic column is installed on the upper die base; the upper die connecting plate is arranged on the guide column in a sliding and sleeving mode and connected with the telescopic end of the first hydraulic column, the upper die connecting plate is provided with an upper die iron core, a pouring gate and a pouring gate communicated with the pouring gate, a lower die is rotationally installed on the lower die base, a brake drum outer sand core is arranged in the lower die, and the lower die is driven by a driving device to rotate; when the shell is cast, the upper mold iron core and the brake drum outer sand core are used for forming a shell cavity; and when the brake part is cast, the end cover is detachably fixed on the lower die. The shell pouring and the brake part centrifugal pouring are completed on the same equipment, the middle step of separate casting of the double-material brake drum is omitted, the time interval of two times of pouring is very short, the connecting position of the two materials is firmer, and the safety of the brake drum is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of brake drum production, and in particular relates to a dual-material brake drum casting centrifuge and a manufacturing method. Background Art

[0002] At present, commercial vehicle brake drums mostly use bimetallic brake drums and ordinary gray iron brake drums, most of which fail due to cracking, followed by cracking and bottoming. Gray iron brake drums have insufficient strength and rigidity. Most bimetallic brake drums are manufactured by punching and spot welding of steel plates and centrifugal casting of brake parts. The steel plate punching and spot welding and centrifugal casting are carried out on different equipment, and the process is cumbersome. The steel plate shell is still prone to cracks, and the mechanical properties are not strong. In addition, due to the different thermal expansion coefficients of steel and iron, it is easy to cause brake drum tearing defects. Summary of the invention

[0003] In view of the above shortcomings, the technical problem to be solved by the present invention is to provide a dual-material brake drum casting centrifuge and a manufacturing method in which the outer shell and the brake part are cast on the same centrifugal equipment, which has simple process, high efficiency and low cost.

[0004] To solve the above-mentioned first technical problem, the technical solution of the present invention is:

[0005] A dual-material brake drum casting centrifuge, comprising: an upper die seat, a lower die seat, a first hydraulic column, an upper die connecting plate, a driving device and an end cover, a guide column is fixed between the upper die seat and the lower die seat, the first hydraulic column is installed on the upper die seat, the upper die connecting plate is slidably sleeved on the guide column and connected to the telescopic end of the first hydraulic column, the upper die connecting plate is provided with an upper die core, a casting port and a runner connected to the casting port, the lower die seat is rotatably provided with a lower die, a brake drum outer sand core is provided in the lower die, and the lower die is driven to rotate by the driving device;

[0006] When casting the shell, the upper mold iron core and the brake drum outer sand core are used to form the shell cavity;

[0007] When casting the brake part, the end cover can be detachably fixed on the lower mold.

[0008] Preferably, the upper die seat is equipped with a second hydraulic column, which passes through the upper die connecting plate and the upper die core. When casting the outer shell, the upper die core, the brake drum outer sand core and the end face of the second hydraulic column jointly form the outer shell cavity.

[0009] Preferably, the upper ends of all the second hydraulic columns are fixedly connected with a second hydraulic column connecting plate.

[0010] Preferably, the upper ends of all the first hydraulic columns are fixedly connected to a second hydraulic column connecting plate.

[0011] Preferably, the upper mold core is hollow inside.

[0012] Preferably, the driving device comprises a motor, a driving pulley and a driven pulley, the driving pulley is mounted on the motor shaft of the motor, the driven pulley is mounted on the lower mold, and the driving pulley and the driven pulley are connected by a belt drive.

[0013] Preferably, the end cover is provided with a through hole for the passage of molten grey iron.

[0014] Preferably, the shell is provided with a shell wavy structure, and the brake part is provided with a brake wavy structure adapted to the shell wavy structure.

[0015] Preferably, the shell is made of gray iron, and the brake part is made of spherical material.

[0016] To solve the above second technical problem, the technical solution of the present invention is:

[0017] A method for manufacturing a dual-material brake drum, based on the dual-material brake drum casting centrifuge, comprises the following steps:

[0018] (1) The first hydraulic column drives the upper mold connecting plate to move upward, and sprays a release agent onto the upper mold iron core, the brake drum outer sand core, and the end surface of the second hydraulic column;

[0019] (2) The first hydraulic column drives the upper mold connecting plate to move downward, and the upper mold iron core, the brake drum outer sand core and the end surface of the second hydraulic column jointly form the shell cavity;

[0020] (3) pouring molten ductile iron at 1400-1450° C. into the shell cavity through the casting port and maintaining the temperature for 3-4 minutes to form a shell blank;

[0021] (4) The first hydraulic column drives the upper die connecting plate to move upward, and the upper die core moves upward. At the same time, the second hydraulic column is extended to keep against the shell blank, and the shell blank remains in the outer sand core of the brake drum;

[0022] (5) The second hydraulic column retracts upward, the end cover is fixedly mounted on the lower die, the motor is started, the motor drives the lower die to rotate at a speed of 750-850 r / min, and molten iron at 1450°-1500° C. is poured into the inner cavity of the outer sand core of the brake drum for a centrifugal time of 5-6 seconds to perform centrifugal casting;

[0023] (6) Let it stand for 2 to 3 minutes to obtain a dual-material brake drum blank.

[0024] After adopting the above technical solution, the beneficial effects of the present invention are:

[0025] (1) On the equipment, the outer shell casting and the brake part centrifugal casting are completed on the same equipment, which reduces the steps of separate casting of the dual-material brake drum, reduces both the transportation cost and the process cost. In addition, the time interval between the two castings is very short, the connection between the two materials is more solid, the brake drum is not easy to tear, and the safety of the brake drum is increased;

[0026] (2) In terms of technology, the shell is directly cast, which is simple and fast, with high work efficiency. The brake part is centrifugal casting, with good casting quality and very few internal defects such as shrinkage cavities, shrinkage, pores, and slag inclusions;

[0027] (3) Structurally, the connection surface between the housing and the brake part is designed with a wave structure, which makes the connection between the housing and the brake part tighter, safer, and the heat dissipation area of ​​the brake drum brake surface is large;

[0028] (4) In terms of material, the brake drum is made of gray iron inside and ductile iron outside, which increases the strength of the brake drum shell;

[0029] (5) The casting uses a brake drum outer sand core and an upper mold iron core. The brake drum outer sand core allows the casting to be removed from the equipment smoothly, and the upper mold iron core can be reused to ensure economy. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a structural schematic diagram of a dual-material brake drum casting centrifuge of the present invention;

[0031] Figure 2 yes Figure 1 Schematic diagram of the cross-sectional structure along the AA direction;

[0032] Figure 3 It is a structural schematic diagram of the centrifugal casting of the brake part of the dual-material brake drum casting centrifuge of the present invention;

[0033] Figure 4 It is a schematic cross-sectional view of a brake drum produced by using the dual-material brake drum casting centrifuge and manufacturing method of the present invention;

[0034] In the figure: 1. upper die base; 2. lower die base; 3. first hydraulic column; 4. upper die connecting plate; 5. end cover; 51. through hole; 6. guide column; 7. upper die core; 8. casting port; 9. runner; 10. lower die; 11. brake drum outer sand core; 12. shell cavity; 13. second hydraulic column; 14. second hydraulic column connecting plate; 15. first hydraulic column connecting plate; 16. motor; 17. driving pulley; 18. driven pulley; 19. shell; 191. shell wavy structure; 20. brake part; 201. brake wavy structure; 21. shell blank. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0036] Embodiment 1

[0037] like Figure 1-Figure 4 As shown together, a fixture for drilling a differential housing comprises: an upper die seat 1, a lower die seat 2, a first hydraulic column 3, an upper die connecting plate 4, a driving device and an end cover 5, a guide column 6 is fixed between the upper die seat 1 and the lower die seat 2, the first hydraulic column 3 is installed on the upper die seat 1, the upper die connecting plate 4 is slidably sleeved on the guide column 6 and connected to the telescopic end of the first hydraulic column 3, the upper die connecting plate 4 is provided with an upper die core 7, a casting port 8 and a runner 9 connected to the casting port 8, the lower die seat 2 is rotatably provided with a lower die 10, a brake drum outer sand core 11 is provided in the lower die 10, and the lower die 10 is driven to rotate by the driving device;

[0038] When casting the housing 19, the upper mold core 7 and the brake drum outer sand core 11 are used to form the housing cavity 12;

[0039] When casting the brake part 20 , the end cover 5 can be detachably fixed on the lower mold 10 .

[0040] The upper die seat 1 is equipped with a second hydraulic column 13, which passes through the upper die connecting plate 4 and the upper die core 7. When casting the outer shell 19, the upper die core 7, the brake drum outer sand core 11 and the end surface of the second hydraulic column 13 together form the outer shell cavity 12.

[0041] The upper ends of all the second hydraulic columns 13 are fixedly connected with second hydraulic column connecting plates 14 , so that all the second hydraulic columns 13 are connected to form a whole, and all the second hydraulic columns 13 move synchronously.

[0042] The upper ends of all the first hydraulic columns 3 are fixedly connected with the first hydraulic column connecting plates 15 , so that all the first hydraulic columns 3 are connected to form a whole, and all the first hydraulic columns 3 move synchronously.

[0043] The upper mold core 7 is hollow inside to reduce weight and cost.

[0044] The driving device includes a motor 16, a driving pulley 17 and a driven pulley 18. The driving pulley 17 is installed on the motor shaft of the motor 16, and the driven pulley 18 is installed on the lower mold 10. The driving pulley 17 and the driven pulley 18 are connected by belt transmission.

[0045] The end cover 5 is provided with a through hole 51 for the grey iron liquid to pass through.

[0046] The outer shell 19 is provided with an outer shell wavy structure 191, and the brake part 20 is provided with a brake wavy structure 201 adapted to the outer shell wavy structure 191, so that the outer shell 19 and the brake part 20 are more tightly connected and safer.

[0047] The outer shell 19 is made of gray iron, and the brake part 20 is made of a spherical material.

[0048] Embodiment 2

[0049] A method for manufacturing a dual-material brake drum, based on the dual-material brake drum casting centrifuge involved in embodiment 1, comprises the following methods:

[0050] (1) The first hydraulic column 3 drives the upper mold connecting plate 4 to move upward, and sprays a mold release agent onto the upper mold core 7, the brake drum outer sand core 11, and the end surface of the second hydraulic column 13;

[0051] (2) The first hydraulic column 3 drives the upper mold connecting plate 4 to move downward, and the upper mold core 7, the brake drum outer sand core 11 and the end surface of the second hydraulic column 13 together form the shell cavity 12;

[0052] (3) molten ductile iron at 1400-1450° C. is poured through the pouring port 8 and then flows into the shell cavity 12 through the runner 9 and maintained for 3-4 minutes to form a shell blank 21;

[0053] (4) The first hydraulic column 3 drives the upper die connecting plate 4 to move upward, and the upper die core 7 moves upward to separate from the shell blank 21. At the same time, the second hydraulic column 13 is extended to keep against the shell 19, and the shell blank 21 remains in the outer sand core 11 of the brake drum;

[0054] (5) The second hydraulic column 13 is retracted, and the end cover 5 is fixedly installed on the lower mold 10 by bolts, the inner cavity of the outer sand core 11 of the brake drum is closed, and the motor 16 is started. The motor 16 drives the lower mold 10 to rotate, and the outer shell blank 21 rotates with it. The speed is 750-850 r / min, and gray iron water at 1450°-1500°C is poured into the inner cavity of the outer sand core 11 of the brake drum. Under the action of centrifugal force, the gray iron water adheres to the outer shell blank 21. The centrifugal time is 5-6 seconds, and centrifugal casting is performed;

[0055] (6) Let it stand for 2 to 3 minutes to form the brake part blank and obtain a dual-material brake drum blank.

[0056] The dual-material brake drum casting centrifuge and manufacturing method of the present invention have the following advantages:

[0057] (1) On the equipment, the outer shell casting and the brake part centrifugal casting are completed on the same equipment, which reduces the steps of separate casting of the dual-material brake drum, reduces both the transportation cost and the process cost. In addition, the time interval between the two castings is very short, the connection between the two materials is more solid, the brake drum is not easy to tear, and the safety of the brake drum is increased;

[0058] (2) In terms of technology, the shell is directly cast, which is simple and fast, with high work efficiency. The brake part is centrifugal casting, with good casting quality and very few internal defects such as shrinkage cavities, shrinkage, pores, and slag inclusions;

[0059] (3) Structurally, the connection surface between the housing and the brake part is designed with a wave structure, which makes the connection between the housing and the brake part tighter, safer, and increases the heat dissipation area of ​​the brake drum brake surface;

[0060] (4) In terms of material, this design uses gray iron inside and ductile iron outside, which increases the strength of the brake drum shell;

[0061] (5) The casting uses a brake drum outer sand core and an upper mold iron core. The brake drum outer sand core allows the casting to be removed from the equipment smoothly, and the upper mold iron core can be reused to ensure economy.

[0062] The above is an example of the best implementation of the present invention, and the parts not described in detail are common knowledge of ordinary technicians in the field. The protection scope of the present invention shall be based on the content of the claims, and any equivalent transformation based on the technical enlightenment of the present invention is also within the protection scope of the present invention.

Claims

1. A dual-material brake drum casting centrifuge, characterized in that: include: An upper die seat, a lower die seat, a first hydraulic column, an upper die connecting plate, a driving device and an end cover, a guide column is fixed between the upper die seat and the lower die seat, the first hydraulic column is installed on the upper die seat, the upper die connecting plate is slidably sleeved on the guide column and connected to the telescopic end of the first hydraulic column, the upper die connecting plate is provided with an upper die core, a casting port and a runner connected to the casting port, the lower die seat is rotatably provided with a lower die, a brake drum outer sand core is provided in the lower die, and the lower die is driven to rotate by the driving device; When casting the shell, the upper mold iron core and the brake drum outer sand core are used to form the shell cavity; When casting the brake part, the end cover can be detachably fixed on the lower mold.

2. The dual-material brake drum casting centrifuge according to claim 1, characterized in that: The upper die seat is equipped with a second hydraulic column, which passes through the upper die connecting plate and the upper die core. When casting the outer shell, the upper die core, the brake drum outer sand core and the end face of the second hydraulic column jointly form the outer shell cavity.

3. The dual-material brake drum casting centrifuge according to claim 2, characterized in that: The upper ends of all the second hydraulic columns are fixedly connected with a second hydraulic column connecting plate.

4. The dual-material brake drum casting centrifuge according to claim 3, characterized in that: The upper ends of all the first hydraulic columns are fixedly connected with a second hydraulic column connecting plate.

5. The dual-material brake drum casting centrifuge according to claim 4, characterized in that: The upper mold core is hollow inside.

6. The dual-material brake drum casting centrifuge according to claim 5, characterized in that: The driving device comprises a motor, a driving pulley and a driven pulley, wherein the driving pulley is mounted on the motor shaft of the motor, and the driven pulley is mounted on the lower mold, and the driving pulley and the driven pulley are connected via a belt transmission.

7. The dual-material brake drum casting centrifuge according to claim 6, characterized in that: The end cover is provided with a through hole for the grey iron liquid to pass through.

8. The dual-material brake drum casting centrifuge according to claim 7, characterized in that: The shell is provided with a shell wavy structure, and the brake part is provided with a brake wavy structure adapted to the shell wavy structure.

9. The dual-material brake drum casting centrifuge according to claim 8, characterized in that: The shell is made of gray iron, and the brake part is made of spherical material.

10. A method for manufacturing a dual-material brake drum, characterized in that: The method is based on the dual-material brake drum casting centrifuge according to claim 9, and includes the following methods: (1) The first hydraulic column drives the upper mold connecting plate to move upward, and sprays a release agent onto the upper mold iron core, the brake drum outer sand core, and the end surface of the second hydraulic column; (2) The first hydraulic column drives the upper mold connecting plate to move downward, and the upper mold iron core, the brake drum outer sand core and the end surface of the second hydraulic column jointly form the shell cavity; (3) pouring molten ductile iron at 1400-1450° C. into the shell cavity through the casting port and maintaining the temperature for 3-4 minutes to form a shell blank; (4) The first hydraulic column drives the upper die connecting plate to move upward, and the upper die core moves upward. At the same time, the second hydraulic column is extended to keep against the shell blank, and the shell blank remains in the outer sand core of the brake drum; (5) The second hydraulic column retracts upward, the end cover is fixedly mounted on the lower die, the motor is started, the motor drives the lower die to rotate at a speed of 750-850 r / min, and molten iron at 1450°-1500° C. is poured into the inner cavity of the outer sand core of the brake drum for a centrifugal time of 5-6 seconds to perform centrifugal casting; (6) Let it stand for 2 to 3 minutes to obtain a dual-material brake drum blank.

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