A conductive rod cold extrusion forming die and a cold extrusion forming process

Abstract

The application discloses a kind of electrically conductive rod cold extrusion forming die and cold extrusion forming process, including fixed die assembly and movable die assembly, movable die assembly includes movable die fixed plate, movable die seat, first punch, second punch, first spring and second spring, movable die seat is fixed on movable die fixed plate, first punch is slidably installed in movable die seat, one end of the second punch has hexagonal boss that passes through first punch, and second punch is slidably arranged in first punch, the two ends of first spring are respectively resisted between movable die fixed plate and first punch, second spring is sleeved on the outside of hexagonal boss, the electrically conductive rod is processed by two times of cold extrusion successively using a set of mould in the application, and hexagonal groove is formed on the electrically conductive rod, compared with traditional two sets of cold extrusion die processing mode, processing efficiency is obviously improved, and meanwhile processing quality can be guaranteed, and production cost is reduced.

Description

Technical Field

[0001] This invention discloses a cold extrusion molding die and a cold extrusion molding process for conductive rods, belonging to the field of metal forming technology. Background Technology

[0002] The development of cold extrusion technology was very slow in its early stages, and for a long time it could only be used to extrude a few soft metals (lead and tin). It wasn't until the late 19th and early 20th centuries that it began to extrude harder non-ferrous metals (zinc, aluminum, copper, brass, etc.) and even steel. The metal cold extrusion forming process involves placing a metal blank in a cold extrusion die, applying pressure to the blank at room temperature through a fixed punch on a press, causing the metal blank to undergo plastic deformation to produce a part. Figure 1 The copper conductive rods commonly used in the circuit field are also processed by two cold extrusion molding processes. The first cold extrusion shapes the outer diameter, and the second cold extrusion processes the hexagonal groove at one end of the conductive rod. Finally, threads are processed on the conductive rod. In the cold extrusion process, the traditional processing method requires two sets of cold extrusion dies. This requires manual insertion of the copper rod into the two sets of cold extrusion dies twice, which limits the cold extrusion processing efficiency of the conductive rod and cannot reduce the production cost. Summary of the Invention

[0003] The purpose of this invention is to solve the problems in the prior art by providing a cold extrusion molding die and a cold extrusion molding process for conductive rods.

[0004] This invention achieves the above-mentioned objective through the following technical solution: a cold extrusion forming die for a conductive rod, comprising a fixed die assembly and a moving die assembly. The moving die assembly includes a moving die fixing plate, a moving die base, a first punch, a second punch, and a first spring. The moving die base is fixed on the moving die fixing plate. The first punch is slidably mounted within the moving die base. One end of the second punch has a hexagonal protrusion penetrating the first punch, and the second punch is slidably disposed within the first punch. The first spring is sleeved on the outside of the hexagonal protrusion, and its two ends respectively abut against the first and second punches. The first and second punches are held at one end by the action of the first spring. In a flush state, the outer side of the first punch is provided with an annular groove, and multiple sliders are slidably arranged on the moving mold base. One end of each slider has an arc-shaped notch that mates with the annular groove. The moving mold base is also provided with a drive assembly for driving the multiple sliders to slide horizontally. The extension line of the slider sliding direction passes through the axis of the first punch. The fixed mold assembly includes a fixed mold fixing plate, a fixed mold base, a mold core, and a bushing. The fixed mold base is fixed on the fixed mold fixing plate, and the mold core and bushing are installed on the fixed mold base. The mold core has a first forming hole, one end of the bushing is located in the first forming hole, and the bushing has a second forming hole.

[0005] Preferably, the moving mold base is provided with a plurality of guide bosses distributed at equal angles around the axis of the first punch, and the slider is slidably disposed between two adjacent guide bosses.

[0006] Preferably, the drive assembly includes a gear ring, a gear, a motor, and a mounting plate. The guide boss has an arc surface on the side away from the first punch. The inner diameter of the gear ring is equal to the diameter of the arc surface. The mounting plate has a sleeve structure in the middle and is fixedly connected to the moving mold base by bolts. The first punch is slidably disposed with the mounting plate. The gear meshes with the gear ring and is fixed on the output shaft of the motor. The motor is fixed on the moving mold base. The gear ring has a number of through slots equal to the number of sliders. The difference in distance between the two ends of the through slots and the axis of the first punch is greater than the depth of the annular groove. One end of the slider is provided with a pin located in the through slot.

[0007] Preferably, the inner side of the gear ring has an annular protrusion, and the slider has a concave protrusion on the side away from the annular groove. The annular protrusion is located in the recess of the protrusion, and the pin is mounted on the protrusion.

[0008] Preferably, the slider is provided with eight, and the eight arc-shaped notches form a complete circle when they abut against the annular groove.

[0009] Preferably, the moving mold fixing plate is provided with a guide sleeve, and the fixed mold fixing plate is provided with a guide post that cooperates with the guide sleeve.

[0010] Preferably, a mold sleeve is fixedly installed on the moving mold base, and the upper end of the mold core has a conical surface that mates with the mold sleeve, wherein the lower end diameter of the conical surface is larger than its upper end diameter.

[0011] Preferably, the moving mold base is provided with an ejection assembly, which includes an ejector rod and a second spring. The ejector rod has a stepped shaft structure, and its middle diameter is larger than its two end diameters. The second spring is sleeved on the outside of the ejector rod and applies a force away from the mold core to the ejector rod. One end of the ejector rod passes through the moving mold fixing plate, and the other end extends into the second forming hole.

[0012] A cold extrusion molding process for a conductive rod includes the following steps:

[0013] S1: Prepare the blank material of copper and cut it into copper rods according to fixed dimensions;

[0014] S2: Adjust the relative positions of the first punch and the second punch so that the ends of the two punches protruding from the moving mold base are flush. Then, rely on the drive assembly to drive the slider to slide so that one end of the slider slides into the annular groove.

[0015] S3: The copper rod is placed in the first forming hole. The external power mechanism drives the moving mold assembly to descend to a height LI towards the fixed mold assembly for the first mold closing. The moving mold base and the mold core do not contact each other. The copper rod undergoes plastic deformation due to the extrusion force, thereby filling the second forming hole.

[0016] S4: The moving mold assembly and the fixed mold assembly open the mold for the first time. Then the drive assembly drives the slider to disengage from the annular groove. The external power mechanism drives the moving mold assembly to descend again towards the fixed mold assembly by a height of L2, where L2>L1, until the moving mold base and the mold core come into contact. After the first punch comes into contact with the copper rod, it remains stationary. The second punch moves relative to the first punch and forms a hexagonal groove at one end of the copper rod.

[0017] S5: The moving mold assembly and the fixed mold assembly are opened for the second time, and the formed copper rod is unloaded. Then, a thread is processed at one end of the copper rod to obtain the finished conductive rod.

[0018] Compared with the prior art, the beneficial effects of the present invention are:

[0019] By setting up a moving mold assembly, a fixed mold assembly, a slider, and a drive assembly, the first punch and the second punch are nested and installed in the moving mold base. The first punch has an annular groove. The drive assembly can drive the slider to slide horizontally a certain distance. When one end of the slider is in the annular groove, the first punch and the second punch will not move relative to each other. In this way, the first cold extrusion forming of the outer diameter of the conductive rod can be achieved. When the slider leaves the annular groove, during the second cold extrusion, the first punch is subjected to a force that compresses the first spring and moves relative to the second punch. This allows the second punch to form a hexagonal groove on the conductive rod. This processing method effectively improves the forming efficiency of the conductive rod and reduces the production cost. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the conductive rod.

[0021] Figure 2 This is a schematic diagram of the structure of a cold extrusion molding die for a conductive rod according to the present invention;

[0022] Figure 3 This is a cross-sectional view of a cold extrusion molding die for a conductive rod according to the present invention;

[0023] Figure 4 This is a schematic diagram of the installation structure of the moving mold base and the drive assembly in this invention;

[0024] Figure 5 This is a schematic diagram of the structure of the moving mold base, gear ring, and slider in this invention;

[0025] Figure 6 This is a schematic diagram of the drive assembly, the first punch, and the second punch in this invention;

[0026] Figure 7 This is a schematic diagram of the structure of the first punch and the second punch in this invention;

[0027] Reference numerals: 1. Hexagonal groove; 2. Moving mold base; 3. Moving mold fixing plate; 4. Guide sleeve; 5. Mold sleeve; 6. Fixed mold base; 7. Fixed mold fixing plate; 8. Guide post; 9. First forming hole; 10. First punch; 11. Drive assembly; 12. Second punch; 13. Slider; 14. First spring; 15. Hexagonal protrusion; 16. Mold core; 17. Insert; 18. Ejector pin; 19. Second spring; 20. Conical surface; 21. Mounting plate; 22. Motor; 23. Guide boss; 24. Gear ring; 25. Through groove; 26. Pin; 27. Protrusion; 28. Annular protrusion; 29. ​​Annular groove; 30. Second forming hole; 31. Gear. Detailed Implementation

[0028] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] like Figures 1-7 As shown, a cold extrusion molding die for a conductive rod includes a fixed die assembly and a moving die assembly. The moving die assembly includes a moving die fixing plate 3, a moving die base 2, a first punch 10, a second punch 12, and a first spring 14. The moving die base 2 is fixed on the moving die fixing plate 3. The first punch 10 is slidably installed inside the moving die base 2. One end of the second punch 12 has a hexagonal protrusion 15 that penetrates the first punch 10, and the second punch 12 is slidably disposed inside the first punch 10. The first spring 14 is sleeved on the outside of the hexagonal protrusion 15, and its two ends abut against the first punch 10 and the second punch 12 respectively. Under the action of the first spring 14, the first punch 10 and the second punch 12 are kept at one end flush. The outer side of the first punch 10 is provided with an annular groove 29. Multiple sliders 13 are slidably arranged on the moving mold base 2. One end of the multiple sliders 13 has an arc-shaped notch that cooperates with the annular groove 29. The moving mold base 2 is also provided with a drive assembly 11 for driving the multiple sliders 13 to slide horizontally. The extension line of the sliding direction of the sliders 13 passes through the axis of the first punch 10. The fixed mold assembly includes a fixed mold fixing plate 7, a fixed mold base 6, a mold core 16 and a bushing 17. The fixed mold base 6 is fixed on the fixed mold fixing plate 7. The mold core 16 and the bushing 17 are installed on the fixed mold base 6. The mold core 16 has a first forming hole 9. One end of the bushing 17 is located in the first forming hole 9, and the bushing 17 has a second forming hole 30.

[0030] The moving mold base 2 is provided with multiple guide bosses 23 distributed at equal angles around the axis of the first punch 10. The slider 13 is slidably disposed between two adjacent guide bosses 23. The slider 13 is restricted to slide between the two guide bosses 23, while the upper and lower sides of the slider 13 are restricted by the moving mold base 2 and the mounting plate 21, thereby ensuring that the sliding direction of the slider 13 passes through the axis of the first punch 10.

[0031] The drive assembly 11 includes a gear ring 24, a gear 31, a motor 22, and a mounting plate 21. The guide boss 23 has an arc surface on the side away from the first punch 10. The inner diameter of the gear ring 24 is equal to the diameter of the arc surface. The middle part of the mounting plate 21 is a sleeve structure, and the mounting plate 21 is fixedly connected to the moving mold base 2 by bolts. The first punch 10 is slidably disposed with the mounting plate 21. The gear 31 meshes with the gear ring 24, and the gear 31 is fixed on the output shaft of the motor 22. The motor 22 is fixed on the moving mold base 2. The gear ring 24 is provided with a number of through slots equal to the number of sliders 13. 25. The distance difference between the two ends of the through groove 25 and the axis of the first punch 10 is greater than the depth of the annular groove 29. One end of the slider 13 is provided with a pin 26 located in the through groove 25. After the moving mold assembly, the drive assembly 11 and the slider 13 are assembled, the first punch 10 is kept in contact with the moving mold base 2 under the action of the first spring 14. At this time, the slider 13 is facing the annular groove 29. When the motor 22 drives the gear 31 to rotate in the forward direction, the gear ring 24 meshes with the gear 31, and the relative position of the pin 26 and the through groove 25 changes, so that the pin 26 drives the slider. Slide 13 towards the annular groove 29 until one end of the slider 13 is located inside the annular groove 29. At this time, the first punch 10 is restricted by the slider 13 and cannot move upward. The length of the first spring 14 remains unchanged. Since one end of the second punch 12 is in contact with the moving mold fixing plate 3, the second punch 12 also cannot move upward. Thus, during the first cold extrusion, the ends of the first punch 10 and the second punch 12 remain flush, which allows for the cold extrusion of the outer diameter of the copper rod. When the motor 22 drives the gear 31 to rotate in the opposite direction, the gear ring 24 meshes with the gear 31. When the slider 13 is disengaged from the annular groove 29 by the pin 26, the restriction on the upward movement of the first punch 10 is lifted. During the second cold extrusion, when the first punch 10 touches the copper rod, it cannot continue to move downward and begins to compress the first spring 14. Meanwhile, the second punch 12 can continue to move downward with the moving mold fixing plate 3, so that the second punch 12 and the first punch 10 move relative to each other. Thus, the hexagonal protrusion 15 begins to extend out of the surface of the first punch 10 and performs a second cold extrusion on one end of the copper rod, thereby forming the hexagonal groove 1.

[0032] The inner side of the gear ring 24 has an annular protrusion 28. The slider 13 has a concave protrusion 27 on the side away from the annular groove 29. The annular protrusion 28 is located in the recess of the protrusion 27. The pin 26 is installed on the protrusion 27. The protrusion 27 and the pin 26 can connect one end of the slider 13 to the gear ring 24. When the gear 31 drives the gear ring 24 to rotate, the contact position between the pin 26 and the through groove 25 changes. In this way, the gear ring 24 can drive the slider 13 to slide horizontally, so that one end of the slider 13 is embedded in the annular groove 29, so that the first punch 10 cannot move upward, or one end of the slider 13 is disengaged from the annular groove 29, so that the first punch 10 moves relative to the second punch 12 when it is subjected to an upward force, thus preparing for the second cold extrusion of the copper rod.

[0033] Eight sliders 13 are provided. The eight arc-shaped notches form a complete circle when they contact the annular groove 29. One end of each slider 13 is embedded in the annular groove 29, which can provide a stable support for the annular groove 29. This prevents the first punch 10 from moving during the first cold extrusion forming of the copper rod. A guide sleeve 4 is provided on the moving die fixing plate 3, and a guide post 8 that cooperates with the guide sleeve 4 is provided on the fixed die fixing plate 7. The cooperation between the guide post 8 and the guide sleeve 4 allows the first punch 10 and the second punch 12 to be smoothly aligned with the first forming hole 9, thereby ensuring the smooth progress of the cold extrusion process. A die sleeve 5 is fixedly installed on the moving die base 2. The upper end of the die core 16 has a conical surface 20 that cooperates with the die sleeve 5. The lower diameter of the conical surface 20 is larger than its upper diameter. The die sleeve 5 can restrict the die core 16 from moving upward and disengaging from the fixed die base 6, so that all three are firmly installed on the fixed die fixing plate 7.

[0034] The moving mold base 2 is equipped with an ejection assembly, which includes an ejector rod 18 and a second spring 19. The ejector rod 18 has a stepped shaft structure, and its middle diameter is larger than the diameters at both ends. The second spring 19 is sleeved on the outside of the ejector rod 18 and applies a force to the ejector rod 18 away from the mold core 16. One end of the ejector rod 18 passes through the moving mold fixing plate 3, and the other end extends into the second forming hole 30. When the copper rod undergoes two cold extrusion processes, the copper rod undergoes plastic deformation and fills the second forming hole 30, eventually contacting the ejector rod 18. The ejector rod 18 cannot move downward, making the density of the copper rod more uniform in various positions after cold extrusion. Subsequently, an external pushing mechanism applies a pushing force to the ejector rod 18, causing the ejector rod 18 to eject the copper rod from the second forming hole 30 and the first forming hole 9 to complete the unloading action.

[0035] A cold extrusion molding process for a conductive rod includes the following steps:

[0036] S1: Prepare the blank material of copper and cut it into copper rods according to fixed dimensions;

[0037] S2: Adjust the relative positions of the first punch 10 and the second punch 12 so that the ends of the two protruding from the moving mold base 2 are flush. Then, rely on the drive assembly 11 to drive the slider 13 to slide, so that one end of the slider 13 slides into the annular groove 29.

[0038] S3: The copper rod is placed in the first forming hole 9. The external power mechanism drives the moving mold assembly to descend to a height LI towards the fixed mold assembly for the first mold closing. The moving mold base 2 and the mold core 16 are not in contact. The copper rod undergoes plastic deformation due to the extrusion pressure, thereby filling the second forming hole 30.

[0039] S4: The moving mold assembly and the fixed mold assembly open the mold for the first time. Then, the drive assembly 11 drives the slider 13 to disengage from the annular groove 29. The external power mechanism drives the moving mold assembly to descend towards the fixed mold assembly again by a height of L2, where L2>L1, until the moving mold base 2 and the mold core 16 come into contact. After the first punch 10 comes into contact with the copper rod, it remains stationary. The second punch 12 moves relative to the first punch 10 and forms a hexagonal groove 1 at one end of the copper rod.

[0040] S5: The moving mold assembly and the fixed mold assembly are opened for the second time, and the formed copper rod is unloaded. Then, a thread is processed at one end of the copper rod to obtain the finished conductive rod.

[0041] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0042] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. An electrically conductive rod cold extrusion forming die comprising a fixed die assembly and a movable die assembly, characterised in that, The movable die assembly comprises a movable die fixing plate (3), a movable die seat (2), a first punch (10), a second punch (12) and a first spring (14), the movable die seat (2) is fixed on the movable die fixing plate (3), the first punch (10) is slidingly installed in the movable die seat (2), one end of the second punch (12) has a hexagonal protruding column (15) penetrating through the first punch (10), and the second punch (12) is slidingly arranged in the first punch (10), the first spring (14) is sleeved on the outer side of the hexagonal protruding column (15), and the two ends thereof are in abutment with the first punch (10) and the second punch (12) respectively, the first punch (10) and the second punch (12) are kept in a flush state at one end under the action of the first spring (14), the outer side of the first punch (10) is provided with an annular groove (29), a plurality of sliding blocks (13) are slidingly arranged on the movable die seat (2), one end of the plurality of sliding blocks (13) has an arc-shaped notch matched with the annular groove (29), the movable die seat (2) is further provided with a driving assembly (11) for driving the plurality of sliding blocks (13) to slide horizontally, the extension line of the sliding direction of the sliding blocks (13) passes through the axis of the first punch (10), the fixed die assembly comprises a fixed die fixing plate (7), a fixed die seat (6), a mold core (16) and a sleeve (17), the fixed die seat (6) is fixed on the fixed die fixing plate (7), the mold core (16) and the sleeve (17) are installed on the fixed die seat (6), the mold core (16) has a first forming hole (9) therein, one end of the sleeve (17) is located in the first forming hole (9), and the sleeve (17) has a second forming hole (30) therein, the movable die seat (2) is provided with a plurality of guide bosses (23) distributed at equal angles with the axis of the first punch (10) as the center, the sliding blocks (13) are slidingly arranged between two adjacent guide bosses (23), the driving assembly (11) comprises a gear ring (24), a gear (31), a motor (22) and a mounting plate (21), the side of the guide boss (23) away from the first punch (10) is a circular arc surface, the inner diameter of the gear ring (24) is equal to the diameter of the circular arc surface, the middle part of the mounting plate (21) is a sleeve structure, and the mounting plate (21) is fixedly connected with the movable die seat (2) through bolts, the first punch (10) and the mounting plate (21) are slidingly arranged, the gear (31) is engaged with the gear ring (24), and the gear (31) is fixed on the output shaft of the motor (22), the motor (22) is fixed on the movable die seat (2), the gear ring (24) is provided with a plurality of through grooves (25) equal in number to the sliding blocks (13), the distance between the two ends of the through groove (25) to the axis of the first punch (10) is greater than the depth of the annular groove (29), and one end of the sliding block (13) is provided with a latch (26) located in the through groove (25).

2. The cold extrusion forming die for a conductive rod according to claim 1, characterized by The inner side of the gear ring (24) has a ring protrusion (28), the slider (13) is provided with a concave-shaped protrusion (27) away from one side of the ring-shaped groove (29), the ring protrusion (28) is located in the notch of the protrusion (27), and the plug (26) is installed on the protrusion (27).

3. The cold extrusion forming die for a conductive rod according to claim 1, characterized by The slider (13) is provided with eight, and the eight arc-shaped notches form a complete circle when they are in contact with the ring-shaped groove (29).

4. The cold extrusion forming die for a conductive rod according to claim 1, characterized by The movable mold fixing plate (3) is provided with a guide sleeve (4), and the fixed mold fixing plate (7) is provided with a guide column (8) matched with the guide sleeve (4).

5. The cold extrusion forming die for an electrically conductive rod according to claim 1, characterized in that, The movable mold base (2) is fixedly provided with a mold sleeve (5), the upper end of the mold core (16) has a conical surface (20) matched with the mold sleeve (5), and the lower end diameter of the conical surface (20) is greater than the upper end diameter.

6. The cold extrusion forming die for an electrically conductive rod according to claim 1, characterized by The movable mold base (2) is provided with an ejection assembly, the ejection assembly comprises a top rod (18) and a second spring (19), the top rod (18) is a stepped shaft structure, and the middle part has a larger diameter than the two ends, the second spring (19) is sleeved outside the top rod (18) and applies a force away from the mold core (16) to the top rod (18), one end of the top rod (18) penetrates through the movable mold fixing plate (3), and the other end extends into the second forming hole (30).

7. A process for cold extrusion forming of an electrically conductive rod using a cold extrusion forming die according to any one of claims 1 to 6, characterized in that, The method comprises the following steps: S1: Prepare the blank of copper material, and cut it into a copper bar according to the fixed size; S2: Adjust the relative position of the first punch (10) and the second punch (12) so that the two ends of the movable mold base (2) are flush, then drive the slider (13) to slide by relying on the driving assembly (11), and slide one end of the slider (13) into the ring-shaped groove (29); S3: Place the copper bar in the first forming hole (9), drive the movable mold assembly to descend by LI height towards the fixed mold assembly by an external power mechanism for the first time, the movable mold base (2) is not in contact with the mold core (16), the copper bar is plastically deformed due to the extrusion force, and thus fills the second forming hole (30); S4: The movable mold assembly and the fixed mold assembly are opened for the first time, then the driving assembly (11) drives the slider (13) to separate from the ring-shaped groove (29), and the movable mold assembly is driven by the external power mechanism to descend again towards the fixed mold assembly by L2 height, wherein L2>L1, until the movable mold base (2) is in contact with the mold core (16), the first punch (10) is kept stationary after being in contact with the copper bar, and the second punch (12) is in relative motion with the first punch (10) to form a hexagonal groove (1) at one end of the copper bar; S5: The movable mold assembly and the fixed mold assembly are opened for the second time, and the formed copper bar is unloaded, then threads are machined at one end of the copper bar to obtain a finished product conductive rod.

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