A forging die assembly with a marked balance axis

Abstract

The utility model discloses a kind of forging die assembly with marking balance shaft, comprising: lower die holder, top surface is equipped with preforming lower cavity and finish forging lower cavity;Upper die holder, bottom surface is equipped with preforming upper cavity and finish forging upper cavity;Driving assembly, driving upper die holder and lower die holder clamping and parting, when clamping, preforming lower cavity and preforming upper cavity combination form preforming cavity and finish forging lower cavity and finish forging upper cavity combination form finish forging cavity, pre-positioning concave-convex piece is arranged on the cavity wall of preforming cavity, and finish-positioning concave-convex piece is arranged on the cavity wall of finish forging cavity.The forging die assembly with marking balance shaft is respectively set corresponding pre-positioning concave-convex piece and finish-positioning concave-convex piece on the cavity wall of preforming cavity and the cavity wall of finish forging cavity, it is favorable to that blank can be accurately placed into finish forging lower cavity after once preforming forming, improve finish forging precision to blank when finish forging, so as to accurately form corresponding mark in the predetermined position of product, improve the quality of final product.

Description

Technical Field

[0001] This utility model relates to the field of balance shaft forging technology, and in particular to a forging die assembly for a marked balance shaft. Background Technology

[0002] The engine balance shaft is a core component used to counteract the reciprocating inertial force of the engine and reduce operating vibration. It is mostly used in engines with four or more cylinders or high speeds. Its core function is to improve the smoothness of operation and reduce noise and mechanical wear.

[0003] Engine balance shafts are typically formed by integrally connecting the shaft body and balance weights. To ensure the eccentricity of the balance weights, they are usually manufactured using hot die forging molds. To improve forging accuracy and efficiency, the upper die base of the mold usually has a pre-forging upper cavity and a final forging upper cavity, while the lower die base has a pre-forging lower cavity and a final forging lower cavity. When the mold is closed, the pre-forging upper cavity and the pre-forging lower cavity combine to form the pre-forging cavity, and the blank is pre-forged once. The final forging upper cavity and the final forging lower cavity combine to form the final forging cavity, and the blank after the first pre-forging is subjected to a second final forging to improve forging accuracy. For example, Chinese utility model patents disclosed in CN212945210U, CN217647413U, and CN212944968U all adopt a two-stage pressure forming method to improve the forming accuracy of the final forging.

[0004] To facilitate differentiation between different types of balance shafts, marking protrusions and recesses are typically placed on the walls of the lower or upper cavity of the final forging die. During the second forming process, the blank is marked with corresponding forming marks to distinguish different engine balance shafts. However, during forging, after the blank is placed into the lower cavity of the final forging die following the first pre-forging, deviations, especially in radial angle, can occur. This leads to misalignment of the forming marks on the final product, affecting the final product's forming quality. Furthermore, while integrating the upper pre-forging and upper final forging cavities into the upper die holder and the upper and lower final forging cavities into the lower die holder improves forging accuracy and efficiency, when one cavity wears out, the entire die holder (either the upper or lower die holder) needs to be replaced, increasing maintenance and replacement costs.

[0005] Therefore, it is necessary to improve the forging dies with marked balance shafts in the existing technology. Utility Model Content

[0006] The purpose of this invention is to overcome the defects in the existing technology and provide a forging die assembly with a marked balance shaft that ensures forging accuracy and quality and reduces maintenance and replacement costs.

[0007] To achieve the above-mentioned technical effects, the technical solution of this utility model is: a forging die assembly with a marked balance shaft, comprising: The lower die base is horizontally positioned and has a pre-forging lower cavity and a final forging lower cavity on its top surface. The upper die base is horizontally positioned above the lower die base and has a pre-forging upper cavity and a final forging upper cavity on its bottom surface; The driving component drives the upper mold base and the lower mold base to close and separate the mold. When the mold is closed, the pre-forging lower cavity and the pre-forging upper cavity combine to form a pre-forging cavity, and the final forging lower cavity and the final forging upper cavity combine to form a final forging cavity. The cavity wall of the final forging cavity is provided with marking protrusions and recesses. In the mold separation state, the upper mold base and the lower mold base are separated. The pre-forging cavity has a pre-positioning protrusion and a convex part on its cavity wall, and the final forging cavity has a final positioning protrusion and a convex part on its cavity wall that corresponds to the pre-positioning protrusion and a convex part.

[0008] Preferably, in order to reduce mold wear and extend mold service life, the marking protrusion is a marking recess, the pre-positioning protrusion is a pre-positioning recess, and the final positioning protrusion is a final positioning recess.

[0009] Preferably, in order to improve positioning accuracy, at least two of the pre-positioning recesses and the final positioning recesses are provided.

[0010] Preferably, in order to further improve the positioning accuracy, two pre-positioning recesses are provided, which are respectively provided on the cavity wall of the pre-forging upper cavity and the cavity wall of the pre-forging lower cavity; two final positioning recesses are provided, which are respectively provided on the cavity wall of the final forging upper cavity and the cavity wall of the final forging lower cavity.

[0011] Preferably, in order to facilitate the forging and forming of the billet, the marking recess is provided on the cavity wall of the final forging lower cavity.

[0012] Preferably, in order to reduce replacement and maintenance costs, the upper die holder includes a pre-forging upper die and a final forging upper die that are detachably connected, with the pre-forging upper cavity and the final forging upper cavity respectively disposed on the pre-forging upper die and the final forging upper die; the lower die holder includes a pre-forging lower die and a final forging lower die that are detachably connected, with the pre-forging lower cavity and the final forging lower cavity respectively disposed on the pre-forging lower die and the final forging lower die.

[0013] Preferably, in order to facilitate the formation of marks of different shapes and sizes on the product, the final forging die includes a die body and an insert detachably connected to the die body. The marking protrusions and recesses are disposed on the insert. The die body is provided with an inlay through hole extending in the vertical direction. The circumferential outer edge of the insert is sealed and fitted to the circumferential inner wall of the insert.

[0014] Preferably, in order to achieve a convenient detachable connection between the insert and the lower mold body, the marking protrusion is provided at the top of the insert, and the bottom end of the insert is connected to the bottom end of the lower mold body by a first bolt.

[0015] Preferably, in order to improve positioning accuracy, a guide boss and a guide recess are provided between the lower mold base and the upper mold base, which are interlocked in the vertical direction. In the mold-closed state, the guide boss and the guide recess are adjacent to the pre-forging cavity and / or the final forging cavity.

[0016] Preferably, in order to improve the pre-forging quality, the pre-forging cavity includes a balance block pre-forging cavity and a balance shaft pre-forging cavity connected to both ends of the balance block pre-forging cavity, wherein the guide boss and the guide recess cooperate with the balance shaft pre-forging cavity and surround the balance block pre-forging cavity.

[0017] In summary, compared with the prior art, the forging die assembly with marking balance shaft of this utility model, by setting corresponding pre-positioning and final positioning protrusions on the cavity walls of the pre-forging cavity and the final forging cavity respectively, facilitates the accurate placement of the billet into the lower cavity of the final forging after one pre-forging, improves the forging accuracy of the billet during final forging, and enables the precise forming of corresponding marks at the predetermined positions of the product, thereby improving the quality of the final product. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of the first embodiment; Figure 2 yes Figure 1 A schematic diagram of the cross-sectional structure; Figure 3 This is a structural schematic diagram of another usage state of the first embodiment; Figure 4 yes Figure 3 An explosion diagram; Figure 5 This is a schematic diagram of the frame structure of the first embodiment; Figure 6 This is a schematic diagram of the translation unit in the first embodiment; Figure 7 This is a schematic diagram of the upper mold base in the first embodiment; Figure 8 yes Figure 7 An explosion diagram; Figure 9 This is a schematic diagram of the lower mold base in the first embodiment; Figure 10 yes Figure 9 An explosion diagram; Figure 11 This is a schematic diagram of the final forging die in the second embodiment; Figure 12 yes Figure 11 An explosion diagram; Figure 13 yes Figure 11 A schematic diagram of the cross-sectional structure; Figure 14 This is a schematic diagram of the structure of the product forged using this utility model; In the diagram: 1. Lower die holder; 11. Pre-forging lower die; 111. Pre-forging lower cavity; 112. Lower pre-positioning recess; 113. Guide recess; 12. Final forging lower die; 121. Final forging lower cavity; 122. Lower final positioning recess; 123. Marking recess; 13. First bolt; 14. Slide groove; 15. Lifting through hole; 16. Lower die body; 161. Inlay through hole; 17. Insert; 2. Upper die holder; 21. Pre-forging upper die; 211. Pre-forging upper cavity; 212. Upper pre-positioning recess; 213. Guide boss; 22. Final forging upper die; 221. Final forging upper cavity; 222. Upper final positioning recess; 3. Lifting unit; 31. Lifting cylinder; 32. Lifting frame; 33. Guide rod; 4. Translation unit; 41. Translation cylinder; 42. Translation plate; 421. Limiting boss; 43. Connecting pipe; 44. Spring; 45. Sliding plate; 46. Sliding rod; 47. Connecting strip; 5. Frame; 51. Base; 52. Support column; 53. Support block; 54. Pressure plate; 541. Guide through hole; 55. Bracket; 551. Guide sleeve; 56. Slide rail; 57. 58. Fourth bolt; 6. Ejector assembly; 61. Lifting cylinder; 62. Lifting plate; 63. Lower ejector rod; 631. Inserting protrusion; 64. Upper ejector rod; 641. Inserting sleeve; 642. Lifting boss; 7. Splicing assembly; 71. Splicing strip; 72. Second bolt; 73. Third bolt; 74. Third nut; 8. Product; 81. Shaft; 82. Balance block; 83. Connecting shaft; 84. Positioning protrusion; 85. Marking protrusion. Detailed Implementation

[0019] The specific embodiments of this utility model will be further described below with reference to the accompanying drawings and examples. The following examples are only used to more clearly illustrate the technical solution of this utility model and should not be construed as limiting the scope of protection of this utility model.

[0020] First Embodiment

[0021] like Figures 1-10 As shown, a forging die assembly with a marked balance shaft according to the first embodiment of this utility model includes: The lower die base 1 is horizontally arranged and has a pre-forging lower cavity 111 and a final forging lower cavity 121 on its top surface; The upper die base 2 is horizontally positioned above the lower die base 1 and has a pre-forging upper cavity 211 and a final forging upper cavity 221 on its bottom surface; The drive assembly drives the upper mold base 2 and the lower mold base 1 to close and separate the mold. When the mold is closed, the pre-forging lower cavity 111 and the pre-forging upper cavity 211 combine to form the pre-forging cavity, and the final forging lower cavity 121 and the final forging upper cavity 221 combine to form the final forging cavity. The cavity wall of the final forging cavity is provided with marking protrusions and recesses. In the mold separation state, the upper mold base 2 and the lower mold base 1 are separated. The pre-forging cavity has a pre-positioning protrusion and a convex protrusion on its cavity wall, and the final forging cavity has a final positioning protrusion and a convex protrusion corresponding to the pre-positioning protrusion and a convex protrusion on its cavity wall.

[0022] In this embodiment, when the mold is used, the upper mold base 2 and the lower mold base 1 are first separated by the drive assembly. Then, the batch to be forged is placed in the pre-forging lower cavity 111 of the lower mold base 1. Then, the upper mold base 2 and the lower mold base 1 are closed, so that the pre-forging upper cavity 211 on the upper mold base 2 and the pre-forging lower cavity 111 are combined to form a pre-forging cavity. Since the cavity wall of the pre-forging cavity is provided with pre-positioning concave and convex parts, when the blank is subjected to the first pre-forging, a concave and convex positioning part is formed at the position corresponding to the pre-positioning concave and convex parts.

[0023] Subsequently, the drive assembly controls the upper die holder 2 and lower die holder 1 to separate, removing the pre-forged billet and placing it in the final forging cavity 121 of the lower die holder 1. The billet is positioned by the convex and concave positioning parts on the billet and the final positioning convex and concave parts on the cavity wall of the final forging cavity 121, ensuring precise placement within the cavity and preventing positional shift or angular rotation. Then, the drive assembly controls the upper die holder 2 and lower die holder 1 to close. With the billet in a fixed position, forging processing is performed, resulting in convex and concave markings at the corresponding positions of the marking convex and concave parts under pressure. Finally, the drive assembly controls the upper die holder 2 and lower die holder 1 to separate, removing the billet after the second final forging. Trimming and shaping are then performed to obtain the desired final forging result. Figure 14 Products.

[0024] Compared with the prior art, in this embodiment, the pre-positioning protrusions and concave parts on the pre-forging cavity enable the billet to form a positioning part with protrusions and concave shapes after the first pre-forging. This facilitates the matching of the formed positioning part with the final positioning protrusions and concave parts on the final forging cavity during the subsequent second final forging, thereby achieving precise positioning of the billet and preventing the billet from shifting or rotating during the final forging process. This ensures the final marking on the billet after final forging, improves forging accuracy, and helps to improve the quality of the final product.

[0025] A further improvement is that the marking protrusion is the marking recess 123, the pre-positioning protrusion is the pre-positioning recess, and the final positioning protrusion is the final positioning recess.

[0026] The marking, pre-positioning, and final positioning parts are all designed with recessed shapes. On the one hand, this increases the capacity of the pre-forging and final forging cavities, making it easier to accommodate more blanks and facilitate the forming of the blanks in the recesses. On the other hand, it reduces wear between the blanks and the mold, thereby extending the service life of the mold.

[0027] A further improvement is that the marking recess 123 is provided on the cavity wall of the final forging lower cavity 121, such as... Figure 9 and Figure 10 As shown, compared to setting the marking recess 123 on the cavity wall of the upper cavity 221 of the final forging, setting the marking recess 123 on the cavity wall of the lower cavity 121 of the final forging is beneficial because during the forging process, in addition to being subjected to the die pressure, the billet can also be affected by its own gravity, and enter downward into the marking recess 123, eventually filling the marking recess 123 and forming as shown. Figure 14 The markings on the product are raised at 85.

[0028] A further improvement is that two pre-positioning recesses are provided, one on the cavity wall of the upper pre-forging cavity 211 and the other on the cavity wall of the lower pre-forging cavity 111; two final positioning recesses are provided, one on the cavity wall of the upper final forging cavity 221 and the other on the cavity wall of the lower final forging cavity 121, as shown below. Figures 7-10 As shown, the pre-positioning recess on the pre-forging upper cavity 211 is the upper pre-positioning recess 212, the pre-positioning recess on the pre-forging lower cavity 111 is the lower pre-positioning recess 112, the final positioning recess on the final forging upper cavity 221 is the upper final positioning recess 222, and the final positioning recess on the final forging lower cavity 121 is the lower final positioning recess 122. In this way, the number of pre-positioning recesses and final positioning recesses is increased, ensuring the forming accuracy of the billet in the pre-forging cavity and the final forging cavity, and improving the forming quality of the final product 8. Two positioning protrusions 84 are formed on the final billet. The two positioning protrusions 84 correspond to the lower pre-positioning recess 112 and the upper pre-positioning recess 212 during pre-forging, and the lower final positioning recess 122 and the upper final positioning recess 222 during final forging, respectively.

[0029] A further improvement is that the upper die holder 2 includes a pre-forging upper die 21 and a final forging upper die 22 that are detachably connected, with the pre-forging upper cavity 211 and the final forging upper cavity 221 respectively disposed on the pre-forging upper die 21 and the final forging upper die 22; the lower die holder 1 includes a pre-forging lower die 11 and a final forging lower die 12 that are detachably connected, with the pre-forging lower cavity 111 and the final forging lower cavity 121 respectively disposed on the pre-forging lower die 11 and the final forging lower die 12.

[0030] With the above structure, both the upper die holder 2 and the lower die holder 1 are detachable and separate structures. Thus, when the cavity wall of one of the pre-forging upper cavity 211, the final forging upper cavity 221, the pre-forging lower cavity 111, and the final forging lower cavity 121 experiences severe wear, only the part corresponding to the severely worn location needs to be replaced, without replacing the entire upper die holder 2 or the lower die holder 1, thereby reducing replacement costs.

[0031] The pre-forging upper die 21 and the final forging upper die 22, as well as the pre-forging lower die 11 and the final forging lower die 12, are connected by splicing components 7.

[0032] Specifically, the pre-forging upper die 21, the final forging upper die 22, the pre-forging lower die 11, and the final forging lower die 12 are all rectangular parallelepiped structures with basically the same length, width, and height dimensions and orientation. Both ends of the four dies are provided with splicing grooves extending along their respective width directions, and the cross-sectional shape and size of each splicing groove are the same.

[0033] More specifically, the two ends of the pre-forging upper die 21 and the final forging upper die 22 are flush and connected along their width direction, and the two ends of the pre-forging lower die 11 and the final forging lower die 12 are flush and connected along their width direction, so that the splicing grooves at both ends of the pre-forging upper die 21 and the final forging upper die 22, and the splicing grooves at both ends of the pre-forging lower die 11 and the final forging lower die 12 are combined to form an assembly through groove.

[0034] The drive assembly includes a lifting unit 3 and a translation unit 4. The splicing assembly 7 includes a splicing strip 71, a second bolt 72, a third bolt 73, and a third nut 74. The splicing strip 71 is adapted to the assembly through slot. For the upper die base 2, the ends of the pre-forging upper die 21 and the final forging upper die 22 are connected to the splicing strip 71 by the second bolt 72. The third bolt 73 and the third nut 74 are threaded and connected to the output end of the lifting unit 3, so as to control the upper die base 2 to move in the vertical direction through the lifting unit 3. For the lower die base 3, the ends of the pre-forging lower die 11 and the final forging lower die 12 are connected to the splicing strip 71 by the second bolt 72. One end of the lower die base 11 is connected to the output end of the translation unit 4 by the threaded third bolt 73 and the third nut 74. The translation unit 4 drives the lower die base 1 to move in the length direction parallel to the pre-forging lower die 11.

[0035] More specifically, such as Figure 5 As shown, the forging die assembly of this utility model also includes a frame 5, which includes a horizontal base 51. The top surface of the base 51 is fixedly connected to a horizontal pressure plate 54 through a column 52 and a support block 53. An inverted U-shaped bracket 55 is fixed above the pressure plate 54.

[0036] To achieve smooth lifting and lowering movement of the upper mold base 2, such as Figure 4As shown, the lifting unit 3 includes a lifting cylinder 31 disposed on the top of the bracket 55. The cylinder of the lifting cylinder 31 is vertically downward and fixed above the bracket 55. The bottom end of the piston rod is fixedly connected to a lifting frame 32. The lifting frame 32 is fixedly connected to the upper mold base 2 by a threaded third bolt 73 and a third nut 74. The top of the lifting frame 32 is fixed with a guide rod 33 extending in the vertical direction. The bracket 55 is fixed with a guide sleeve 551 extending in the vertical direction. The guide rod 33 and the guide sleeve 551 are slidably engaged.

[0037] To facilitate the smooth horizontal movement of the lower mold base 1, such as Figure 9 and Figure 10 As shown, both the pre-forging lower die 11 and the final forging lower die 12 are provided with grooves 14 extending along their own length at their bottoms, such as... Figure 5 As shown, the top surface of the pressure platform 54 is provided with two slide rails 56 that are arranged side by side along the width direction of the pre-forging lower die 11 and extend along the length direction of the pre-forging lower die 11. Both ends of the two slide rails 56 are fixedly connected to the pressure platform 54 by threaded fourth bolts 57 and fourth nuts 58. The two slide rails 56 are slidably engaged with the grooves 14 of the pre-forging lower die 11 and the final forging lower die 12, respectively.

[0038] like Figure 5 As shown, the translation unit 4 includes a translation cylinder 41. The cylinder cylinder axial direction is parallel to the length direction of the slide rail 56. The cylinder cylinder is fixed above the base 51. The piston rod is fixedly connected to a translation plate 42. One end of the translation plate 42 facing away from the translation cylinder 41 is integrally formed with a limiting boss 421. The limiting boss 421 is connected to a limiting plate 45 through a spring 44. One end of the limiting plate 45 facing away from the translation cylinder 41 is fixedly connected to a connecting strip 47 through a sliding rod 46. Both ends of the connecting strip 47 are fixedly connected to the lower mold base 1 through a threaded third bolt 73 and a third nut 74. The translation unit 4 includes a connecting pipe 43. One end of the connecting pipe 43 near the translation cylinder 41 is threadedly connected to the translation plate 42, and the other end is sealed and sleeved outside the sliding rod 46.

[0039] With the above design, the piston rod of the translation cylinder 41 extends outward, pushing the translation plate 42 and compressing the spring 44. This causes the limiting protrusion 421 to abut against the sliding plate 45. The piston rod then continues to extend outward, pushing the lower mold base 1, causing it to move to the side and below the upper mold base 2. Figure 1 As shown, this facilitates the removal or placement of the blank; when the piston rod continues to retract, it first pulls the translation plate 42, causing the end of the connecting pipe 43 away from the translation cylinder 41 to abut against the sliding plate 45, thereby pulling the sliding plate 45 to move. Through the sliding rod 46 and the connecting strip 47, it drives the lower mold base 1 to move, so that the lower mold base 1 moves directly below the upper mold base 2, facilitating the lifting unit 3 to drive the upper mold base 2 to descend and close with the lower mold base 1. Figure 3 As shown.

[0040] A further improvement is that a guide boss 213 and a guide recess 113 are provided between the lower mold base 1 and the upper mold base 2, which are interlocked in the vertical direction. In the mold-closed state, the guide boss 213 and the guide recess 113 are adjacent to the pre-forging cavity and / or the final forging cavity. Specifically, the pre-forging cavity includes a balance block pre-forging cavity and a balance shaft pre-forging cavity connected to both ends of the balance block pre-forging cavity. The guide boss 213 and the guide recess 113 cooperate with the balance shaft pre-forging cavity to surround the balance block pre-forging cavity.

[0041] More specifically, the guide boss 213 is integrally formed on the bottom surface of the pre-forging upper die 21 and is located on both sides of the pre-forging upper cavity 212. The guide recess 113 is integrally formed on the top surface of the pre-forging lower die 11 and is located on both sides of the pre-forging lower cavity 111. With this design, by using the interlocking guide boss 213 and guide recess 113, not only can the lower die holder 1 and the upper die holder 2 be precisely connected, but also during the pre-forging process, the guide boss 213 can form a baffle wall, which surrounds both sides of the balance block forming cavity, so that the billet is concentrated in the balance block forming cavity in the middle position, ensuring the forming quality of the balance block 82.

[0042] A further improvement is that the mold assembly of this utility model also includes an ejector assembly 6, which is used to eject the pre-forged billet and the final-forged billet from the pre-forging lower cavity 111 and the final-forging lower cavity 121.

[0043] Specifically, both the pre-forging lower die 11 and the final forging lower die 12 are provided with lifting through holes 15 extending vertically. The lifting through holes 15 on the pre-forging lower die 11 are adjacent to the opening of the pre-forging lower cavity 111, and the lifting through holes 15 on the final forging lower die 12 are adjacent to the opening of the final forging lower cavity 121. The pressure plate 54 is provided with guide through holes 541 corresponding to the lifting through holes 15. The inner diameter of the lifting through holes 15 is larger than the inner diameter of the guide through holes 541. In the mold parting state, the lifting through holes 15 and the guide through holes 541 are coaxial. The ejector assembly 6 includes a lifting cylinder 61, a lifting plate 62, and a lower... The upper push rod 64 and the lower push rod 63 are equal in number and correspond to each other. The cylinder of the lifting cylinder 61 is fixed on the base 51. The top of the piston rod is fixedly connected to a horizontal lifting plate 62. The lower push rod 63 is fixed above the lifting plate 62 and its outer circumferential edge is sealed to the inner circumferential wall of the guide through hole 541. The upper push rod 64 is located inside the lifting through hole 15 and its outer circumferential edge is sealed to the inner circumferential wall of the lifting through hole 15. The length of the lifting through hole 15 is less than the height of the pre-forging lower die 11 and the final forging lower die 12.

[0044] Using the above structure, the position of the lower mold base 1 is adjusted by the translation unit 4, so that the lifting through hole 15 moves to the top of the guide through hole 541. At this time, due to the influence of gravity, the bottom end of the upper ejector rod 64 is in contact with the top surface of the pressure plate 54, and the bottom end is located below the top surface of the lower mold base 1. Since the inner diameter of the lifting through hole 15 is larger than the inner diameter of the guide through hole 541, the upper ejector rod 64 is prevented from falling down from the guide through hole 541.

[0045] Then, the lifting cylinder 61 drives the lifting plate 62 to move upward, so that the top of the lower ejector rod 63 acts on the bottom of the upper ejector rod 64, and the upper ejector rod 64 moves upward, so that the upper ejector rod 64 acts on the flange around the billet, thereby driving the billet to move upward and separate from the pre-forging lower cavity 111 and the final forging lower cavity 121. At the same time, the billet is located on one side of the upper mold base 2, which is convenient for the robot to grasp.

[0046] A further improvement is that the top end of the lower push rod 63 is integrally formed with a plug-in protrusion 631, and the bottom end of the upper push rod 641 is integrally formed with a plug-in sleeve 641. The plug-in protrusion 631 and the plug-in sleeve 641 are plugged into each other. In this way, the contact area between the lower push rod 63 and the upper push rod 64 is increased, ensuring a firm connection between the upper push rod 64 and the lower push rod 63 when the piston rod of the lifting cylinder 61 moves upward.

[0047] A further improvement is that the top of the upper push rod 64 is integrally formed with a lifting boss 642. With this design, after pre-forging and final forging, the flange around the billet is no longer a flat thin sheet. The flange is formed with a lifting recess that matches the lifting boss 642, ensuring a good connection between the upper push rod 64 and the flange. This avoids the billet falling downwards due to poor contact when it is lifted upwards, which would cause deformation and damage to the billet and affect the forming quality.

[0048] Finally, using the forging die of this embodiment, and after edge trimming and shaping, the desired result is obtained as shown below. Figure 14 The product 8 shown includes two balance blocks 82. The two opposite sides of the two balance blocks 82 are fixedly connected by a connecting shaft 83. The two opposite sides are integrally connected with shafts 81 with the same center line. The center line of the shaft 81 is separated from the center line of the connecting shaft 83. The upper and lower sides of one balance block 82 are integrally formed with positioning protrusions 84, and the other balance block 82 is integrally formed with marking protrusions 85.

[0049] Second Embodiment

[0050] like Figures 11-13As shown, the second embodiment of the present invention provides a forging die assembly with a marked balance shaft, which is based on the first embodiment. The difference is that the final forging die 12 includes a lower die body 16 and an insert 17 detachably connected to the lower die body 16. The marked protrusions and concave parts are provided on the insert 17. The lower die body 16 is provided with an inlay through hole 161 extending in the vertical direction. The circumferential outer edge of the insert 17 is sealed and fitted with the circumferential inner wall of the insert 17.

[0051] With this design, the final forging lower die 12 is formed by detachably connecting the insert 17 and the lower die body 16. On the one hand, it is convenient to replace and maintain the final forging lower die 12, reducing replacement and maintenance costs. On the other hand, it is convenient to form marking protrusions 85 of different shapes or sizes on the product 8.

[0052] Specifically, the marking protrusions and concave parts are set at the top of the insert 17, and the bottom end of the insert 17 is connected to the bottom end of the lower mold body 16 by the first bolt 13. This design facilitates the convenient detachable connection between the insert 17 and the lower mold body 16.

[0053] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. A forging die assembly with a marked balance shaft, comprising: The lower die base is horizontally positioned and has a pre-forging lower cavity and a final forging lower cavity on its top surface. The upper die base is horizontally positioned above the lower die base and has a pre-forging upper cavity and a final forging upper cavity on its bottom surface; The driving component drives the upper mold base and the lower mold base to close and separate the mold. When the mold is closed, the pre-forging lower cavity and the pre-forging upper cavity combine to form a pre-forging cavity, and the final forging lower cavity and the final forging upper cavity combine to form a final forging cavity. The cavity wall of the final forging cavity is provided with marking protrusions and recesses. In the mold separation state, the upper mold base and the lower mold base are separated. Its features are: The pre-forging cavity has a pre-positioning protrusion and a convex part on its cavity wall, and the final forging cavity has a final positioning protrusion and a convex part on its cavity wall that corresponds to the pre-positioning protrusion and a convex part.

2. The forging die assembly with marked balance shaft according to claim 1, characterized in that: The marking protrusion is a marking recess, the pre-positioning protrusion is a pre-positioning recess, and the final positioning protrusion is a final positioning recess.

3. The forging die assembly with marked balance shaft according to claim 2, characterized in that: Both the pre-positioning recess and the final positioning recess are provided in at least two forms.

4. The forging die assembly with marked balance shaft according to claim 3, characterized in that: Two pre-positioning recesses are provided, respectively located on the cavity wall of the upper pre-forging cavity and the cavity wall of the lower pre-forging cavity; two final positioning recesses are provided, respectively located on the cavity wall of the upper final forging cavity and the cavity wall of the lower final forging cavity.

5. The forging die assembly with a marked balance shaft according to claim 2, characterized in that: The marking recess is provided on the cavity wall of the final forging lower cavity.

6. The forging die assembly with a marked balance shaft according to any one of claims 1-5, characterized in that: The upper die base includes a pre-forging upper die and a final forging upper die that are detachably connected, with the pre-forging upper cavity and the final forging upper cavity respectively disposed on the pre-forging upper die and the final forging upper die; the lower die base includes a pre-forging lower die and a final forging lower die that are detachably connected, with the pre-forging lower cavity and the final forging lower cavity respectively disposed on the pre-forging lower die and the final forging lower die.

7. The forging die assembly with marked balance shaft according to claim 6, characterized in that: The final forging die includes a die body and an insert detachably connected to the die body. The marking protrusions and recesses are disposed on the insert. The die body has an inlay through hole extending in the vertical direction. The outer circumferential edge of the insert is sealed and fitted to the inner circumferential wall of the insert.

8. The forging die assembly with marked balance shaft according to claim 7, characterized in that: The marking protrusions and recesses are disposed at the top of the insert, and the bottom end of the insert is connected to the bottom end of the lower mold body by a first bolt.

9. The forging die assembly with a marked balance shaft according to any one of claims 1-5, characterized in that: A guide boss and a guide recess are provided between the lower die base and the upper die base, which are interlocked in the vertical direction. In the closed state, the guide boss and the guide recess are adjacent to the pre-forging cavity and / or the final forging cavity.

10. The forging die assembly with marked balance shaft according to claim 9, characterized in that: The pre-forging cavity includes a balance block pre-forging cavity and a balance shaft pre-forging cavity connected to both ends of the balance block pre-forging cavity. The guide boss and the guide recess cooperate with the balance shaft pre-forging cavity and surround the outside of the balance block pre-forging cavity.

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