Knuckle forging die

Abstract

The application relates to a knuckle forging die and belongs to the field of automobile part forging technology. The knuckle forging die comprises a matched upper die and lower die, an upsetting split cavity and a pre-forging cavity are arranged between the upper die and the lower die; the upsetting split cavity is symmetrically provided with first inclined surfaces extending downward from the middle to the two sides at one end of a long fork ear, and the pre-forging cavity is symmetrically provided with second inclined surfaces upwardly inclined away from the pre-forging cavity at one end of the long fork ear. After high-temperature blank is split and shaped through the upsetting split cavity, two symmetrically distributed first inclined surfaces can be formed at the top end. In the pre-forging process, the two formed first inclined surfaces respectively preliminarily contact the upper and lower two second inclined surfaces, the two first inclined surfaces are symmetrically extruded by the upper and lower two second inclined surfaces, a metal flow path can be formed along the second inclined surface, the scrap edge can be smoothly flowed outward along the second inclined surface and flowed out from the gap between the upper and lower dies, the scrap edge can be smoothly discharged, and the scrap edge is prevented from being extruded into the formed long fork ear end.

Description

Technical Field

[0001] This application relates to the field of automotive parts forging technology, and in particular to a steering knuckle forging die. Background Technology

[0002] With the automotive industry's increasing demands for lightweight and structural strength in parts, forging, as a core manufacturing technology for critical structural components such as steering knuckles, directly impacts product performance and production costs due to its forming quality. During forging, folding defects, common surface or near-surface defects, involve abnormal extrusion and embedding of surface material during metal plastic flow, and have become a significant technical challenge restricting process stability.

[0003] In related technologies, the flat forging process typically employs a step-by-step forming method of pre-forging and final forging after splitting the fork. During the pre-forging stage, the blank is initially shaped using a die, and waste edges are removed. However, in existing die structures, the waste edges generated during the pre-forging stage are easily squeezed into the cavity during metal flow due to limitations in die cavity design and forming force control. This results in abnormal extrusion and embedding of waste edges at the end of the steering knuckle's long fork. Ultimately, during subsequent finishing, the cutting stress and residual stress within the workpiece combine, causing the waste edges to detach and form groove defects on the workpiece.

[0004] The aforementioned defects not only lead to material waste and increased processing costs, but also may cause fatigue cracks in the steering knuckle during service due to localized stress concentration, posing a serious safety hazard. Therefore, it is necessary to study and improve the above structure, and provide a steering knuckle forging die to establish an effective waste removal channel, preventing waste generated during metal flow from being forcibly pressed into the steering knuckle long fork lug, thus avoiding fatal defects. Summary of the Invention

[0005] This application provides a steering knuckle forging die to solve the folding defect problem caused by waste edges being squeezed into the cavity during the forging process of the steering knuckle long fork lug in the related art.

[0006] This application provides a steering knuckle forging die, including: An upper mold and a lower mold that cooperate with each other, wherein an upsetting cavity and a pre-forging cavity are provided between the upper mold and the lower mold; One end of the upset cavity-formed long fork ear is symmetrically provided with a first slope extending downward from the middle to both sides, and one end of the pre-forged cavity-formed long fork ear is symmetrically provided with a second slope that slopes away from the pre-forged cavity.

[0007] In some embodiments, the upsetting cavity includes an upper upsetting cavity disposed on the upper mold and a lower upsetting cavity disposed on the lower mold, wherein the first slope is located on the top surface of the upper upsetting cavity, and the symmetry plane between the two sides of the first slope coincides with the symmetry plane of the upper upsetting cavity.

[0008] In some embodiments, the pre-forging cavity includes an upper pre-forging cavity disposed on the upper mold and a lower pre-forging cavity disposed on the lower mold, wherein the upper pre-forging cavity and the lower pre-forging cavity are respectively provided with the second slope surface; The second slope of the upper pre-forging cavity is inclined away from the upper pre-forging cavity, and the second slope of the lower pre-forging cavity is inclined away from the lower pre-forging cavity.

[0009] In some embodiments, the accommodating space of the upsetting cavity is larger than the accommodating space of the pre-forging cavity.

[0010] In some embodiments, the first slope has a first angle with the horizontal plane, and the second slope has a second angle with the vertical direction, wherein the first angle and the second angle are of the same size.

[0011] In some embodiments, the first slope has a first angle with the horizontal plane, the angle being 5° to 12°.

[0012] In some embodiments, the second slope has a second included angle with the vertical direction, the size of which is 5° to 12°.

[0013] In some embodiments, the size of the first included angle and the size of the second included angle are both 7°.

[0014] In some embodiments, the edges of both the upper and lower upsetting cavities are provided with arc-shaped chamfers.

[0015] In some embodiments, the edges of the upper and lower pre-forging cavities are provided with arc-shaped chamfers, and the surface roughness values ​​of the upper and lower pre-forging cavities are less than or equal to 0.8 μm.

[0016] The beneficial effects of the technical solution provided in this application include: This application provides a steering knuckle forging die. Due to the cooperation of the upper and lower dies, an upsetting cavity and a pre-forging cavity are provided between the upper and lower dies. One end of the long fork lug formed by the upsetting cavity is symmetrically provided with a first slope extending downward from the middle to both sides, and one end of the long fork lug formed by the pre-forging cavity is symmetrically provided with a second slope that is inclined away from the pre-forging cavity.

[0017] Therefore, after the high-temperature billet is split and shaped in the upsetting cavity, the top of the long fork ear formed by the high-temperature billet can be formed with two symmetrically distributed first slopes. In the pre-forging process, the two first slopes formed on the high-temperature billet can initially contact the upper and lower second slopes respectively. By using the upper and lower second slopes to symmetrically squeeze the two first slopes, a metal flow path can be formed along the second slope, so that the waste edge can flow outward along the second slope and flow out from the gap between the upper and lower dies, thus realizing the smooth discharge of the waste edge and avoiding the waste edge being squeezed into the formed long fork ear end. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the upset cavity structure according to an embodiment of this application; Figure 2 for Figure 1 Schematic diagram of the cross section at point AA; Figure 3 This is a schematic diagram of the structure of the pre-forging cavity according to an embodiment of this application; Figure 4 This is a schematic diagram of the upper mold in an embodiment of this application; Figure 5 This is a schematic diagram of the lower mold in an embodiment of this application.

[0020] The attached diagram lists the components represented by each number as follows: 1. Upper mold; 2. Lower mold; 3. Upsetting cavity; 31. Upper upsetting cavity; 32. Lower upsetting cavity; 4. Pre-forging cavity; 41. Upper pre-forging cavity; 42. Lower pre-forging cavity; 5. First slope; 6. Second slope; 7. Curved chamfer. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0022] This application provides a steering knuckle forging die to solve the folding defect problem caused by waste edges being squeezed into the cavity during the forging process of the steering knuckle long fork lug in the related art.

[0023] See Figures 1 to 5 As shown, this application embodiment provides a steering knuckle forging die, including: The upper mold 1 and the lower mold 2 cooperate with each other, and the upsetting cavity 3 and the pre-forging cavity 4 are provided between the upper mold 1 and the lower mold 2; The long fork ear formed by the upsetting cavity 3 is symmetrically provided with a first slope 5 extending downward from the middle to both sides, and the long fork ear formed by the pre-forging cavity 4 is symmetrically provided with a second slope 6 in the direction away from the pre-forging cavity 4.

[0024] The steering knuckle forging die of this application provides a first slope 5 and a second slope 6 in the upsetting cavity 3 and the pre-forging cavity 4 of the die, respectively. After the high-temperature billet is split and shaped by the upsetting cavity 3, the top of the long fork lug of the high-temperature billet can be formed with two symmetrically distributed first slopes 5. In the pre-forging process, the high-temperature billet is placed in the pre-forging cavity 4. The two first slopes 5 formed on the high-temperature billet can initially contact the upper and lower second slopes 6 respectively. By symmetrically pressing the two first slopes 5 with the upper and lower second slopes 6, a metal flow path can be formed along the second slopes 6, so that the waste edge can flow outward along the second slopes 6 and flow out from the gap between the upper and lower dies, thus realizing the smooth discharge of the waste edge and preventing the waste edge from being squeezed into the formed long fork ear end.

[0025] Specifically, the upsetting cavity 3 is formed by the upper upsetting cavity 31 on the upper mold 1 and the lower upsetting cavity 32 on the lower mold 2; the pre-forging cavity 4 is formed by the upper pre-forging cavity 41 on the upper mold 1 and the lower pre-forging cavity 42 on the lower mold 2. After the high-temperature billet is pressed into the upsetting cavity 3, the top of its long fork lug undergoes directional plastic deformation along the two inclined surfaces on both sides under the action of the two first slopes 5 symmetrical to the top surface of the upper upsetting cavity 31, forming an inclined structure that matches the first slope 5.

[0026] When the high-temperature billet is placed between the upper and lower pre-forging cavities, the two first slopes 5 formed at the top of its long fork lugs contact the second slopes 6 of the upper and lower pre-forging cavities, respectively. Since the second slopes 6 are inclined away from the cavity, the pressure exerted on the billet by the upper and lower dies is decomposed along the inclined direction of the second slopes 6, forming an axial thrust on the metal. This thrust causes the scrap material to preferentially flow along the gap between the second slopes 6 and the die wall, and ultimately be discharged through the gap between the upper and lower dies, rather than being squeezed to the end of the long fork lugs to form folding defects.

[0027] It should be noted that the larger space of the upsetting cavity 3 allows the billet to flow fully and form a preliminary shape during the splitting stage after the upper and lower dies are closed, avoiding local accumulation of metal due to limited space; the smaller space of the pre-forging cavity 4 controls the further forming of metal through precise cavity contours, and a gap is left after the upper and lower dies are closed during pre-forging to facilitate the discharge of waste edges.

[0028] The space of the pre-forging cavity 4 is smaller than that of the upsetting cavity 3, which allows the amount of waste generated during the pre-forging stage to be controlled within a reasonable range. During the pre-forging stage, the waste is squeezed out of the cavity, and the second slope 6 can squeeze the inclined surface formed by the long fork end of the billet, effectively reducing the metal flow resistance and smoothly discharging the waste.

[0029] In some alternative embodiments: see Figures 1 to 5 As shown, this application embodiment provides a steering knuckle forging die. The upsetting cavity 3 of the steering knuckle forging die includes an upper upsetting cavity 31 disposed on the upper die 1 and a lower upsetting cavity 32 disposed on the lower die 2. The first slope 5 is located on the top surface of the upper upsetting cavity 31, and the symmetry plane between the two first slopes 5 coincides with the symmetry plane of the upper upsetting cavity 31.

[0030] In this embodiment, the upper upsetting cavity 31 and the lower upsetting cavity 32 together form the upsetting cavity 3. In the fork splitting process, after the high-temperature billet is pressed into the upsetting cavity 3, the top of its long fork ear undergoes directional plastic deformation along the two inclined surfaces on both sides under the action of the two first slope surfaces 5 symmetrical to the top surface of the upper upsetting cavity 31, forming an inclined structure that matches the first slope surface 5.

[0031] In the subsequent pre-forging process, the inclined structure can serve as the initial guiding surface for metal flow, facilitating the closure of the upper and lower second slope surfaces 6 of the pre-forging cavity 4 and gradually compressing the inclined structure, forcing the metal to begin lateral flow in advance, and avoiding the risk of backflow caused by sudden extrusion of the waste edge under high pressure at the end.

[0032] In some alternative embodiments: see Figures 1 to 5 As shown, this application embodiment provides a steering knuckle forging die. The pre-forging cavity 4 of the steering knuckle forging die includes an upper pre-forging cavity 41 disposed on the upper die 1 and a lower pre-forging cavity 42 disposed on the lower die 2. The upper pre-forging cavity 41 and the lower pre-forging cavity 42 are respectively provided with a second slope surface 6. The second slope 6 of the upper pre-forging cavity 41 is inclined away from the upper pre-forging cavity 41, and the second slope 6 of the lower pre-forging cavity 42 is inclined away from the lower pre-forging cavity 42.

[0033] In this embodiment, the upper pre-forging cavity 41 and the lower pre-forging cavity 42 together form the pre-forging cavity 4. When the high-temperature billet enters the pre-forging cavity 4, the two first slopes 5 formed at the top of its long fork lugs contact the second slopes 6 of the upper and lower pre-forging cavities, respectively. Since the two second slopes 6 are inclined away from the pre-forging cavity 4, the pressure applied to the billet by the upper and lower dies is decomposed along the inclined direction of the second slopes 6, forming an axial thrust on the metal. This thrust causes the scrap material to preferentially flow along the gap between the second slopes 6 and the die wall, and is eventually discharged through the gap between the upper and lower dies, rather than being squeezed to the end of the long fork lugs to form folding defects.

[0034] In some alternative embodiments: see Figures 1 to 5 As shown, this application embodiment provides a steering knuckle forging die, wherein the upsetting cavity 3 of the steering knuckle forging die has a larger accommodating space than the pre-forging cavity 4.

[0035] The upsetting cavity 3 of the steering knuckle forging die in this embodiment has a larger capacity than the pre-forging cavity 4. The two spaces form a gradient design, which controls the amount of waste generated in the pre-forging stage within a reasonable range. At the same time, the waste can be efficiently discharged in the pre-forging stage by the guidance of the inclined slope, thereby reducing the possibility of waste backflow in the final forging process.

[0036] In some alternative embodiments: see Figures 1 to 5 As shown in the embodiment of this application, a steering knuckle forging die is provided. The first slope 5 of the steering knuckle forging die has a first angle with the horizontal plane, and the second slope 6 has a second angle with the vertical direction. The size of the first angle and the size of the second angle are the same.

[0037] The steering knuckle forging die of this application sets the inclination angle of the first slope 5 and the second slope 6 to the same value, so that the first slope 5 formed on the blank after splitting can fit with the second slope 6 on the pre-forging cavity 4, reducing metal flow resistance, ensuring that the blank does not shift horizontally during pre-forging, and making the scrap edge uniformly stressed during outward flow, avoiding flow resistance differences or stress concentration caused by angle differences, thereby reducing the risk of scrap edge embedding into the blank.

[0038] In some alternative embodiments: see Figures 1 to 5 As shown in the embodiment of this application, a steering knuckle forging die is provided. The first slope 5 of the steering knuckle forging die has a first included angle with the horizontal plane, and the size of the first included angle is 5° to 12°.

[0039] The first included angle range in this embodiment takes into account both the flow characteristics of the metal material and the strength requirements of the mold. A 5° tilt angle ensures smooth flow of waste material, preventing blockage due to a narrow flow path caused by an excessively small angle; the upper limit of 12° prevents uneven stress distribution in the mold cavity caused by an excessively large angle, which would affect the mold life. Within this range, the metal flow direction and the discharge direction of the mold gap form an optimal match, achieving efficient discharge of waste material.

[0040] In some alternative embodiments: see Figures 1 to 5 As shown, this application embodiment provides a steering knuckle forging die, wherein the second slope 6 of the steering knuckle forging die has a second included angle with the vertical direction, the size of the second included angle being 5° to 12°.

[0041] The inclination angle of the second slope 6 in this embodiment corresponds to that of the first slope 5, ensuring the continuity of waste edge flow during the pre-forging stage. This angle range allows the waste edge to maintain low shear stress during flow, while avoiding metal backflow or increased die wear due to excessively steep slopes, thereby achieving a balance between forming quality and die durability.

[0042] In some alternative embodiments: see Figures 1 to 5 As shown in the figure, this application provides a steering knuckle forging die, wherein the size of the first included angle and the size of the second included angle of the steering knuckle forging die are both 7°.

[0043] In this embodiment, the first and second included angles are designed with a uniform angle of 7°. 7° serves as a compromise and optimization value, ensuring stable and controllable metal flow velocity. Simultaneously, the radius of curvature of the flow path is sufficiently large, reducing eddies and stagnation during the flow process. Furthermore, this angle ensures that when the billet is placed on the lower die 2, the contact area between the first slope 5 formed on the billet and the second slope 6 on the lower die 2 is moderate, resulting in a suitable billet extrusion stroke. This allows the upper and lower pre-forging cavities to be filled and waste edges to be discharged outwards, reducing die wear rate and avoiding localized stress concentration caused by excessively small contact areas, thereby improving the overall stability of the die and the efficiency of waste edge discharge.

[0044] In some alternative embodiments: see Figures 1 to 5 As shown in the figure, this application provides a steering knuckle forging die, wherein the edges of the upper upsetting cavity 31 and the lower upsetting cavity 32 of the steering knuckle forging die are provided with arc-shaped chamfers 7.

[0045] The arc-shaped chamfers 7 at the edges of the upper upsetting cavity 31 and the lower upsetting cavity 32 of the steering knuckle forging die in this embodiment of the application can eliminate the sharp angle effect during metal flow, reducing the frictional resistance and crack initiation risk of material in the transition area of ​​the die. By designing a smooth chamfered surface to guide the direction of metal flow, the waste material is preferentially overflowed along the tangent direction of the arc-shaped chamfer 7, rather than accumulating in the right-angle transition area.

[0046] In some alternative embodiments: see Figures 1 to 5 As shown in the embodiment of this application, a steering knuckle forging die is provided. The edges of the upper pre-forging cavity 41 and the lower pre-forging cavity 42 of the steering knuckle forging die are provided with arc-shaped chamfers 7, and the surface roughness values ​​of the upper pre-forging cavity 41 and the lower pre-forging cavity 42 are less than or equal to 0.8 μm.

[0047] In this embodiment of the application, the surface roughness values ​​of the upper pre-forging cavity 41 and the lower pre-forging cavity 42 of the steering knuckle forging die are less than or equal to 0.8 μm. By designing the pre-forging cavity wall with ultra-low surface roughness, the coefficient of friction between the metal and the die can be significantly reduced, minimizing the driving force required for the waste material during flow. At the same time, the smooth surface reduces the adhesion between the metal oxide layer and the die, preventing the waste material from being retained in the cavity due to excessive adhesion during flow, thereby further improving the reliability of waste material discharge.

[0048] In the description of this application, it should be noted that the terms "upper," "lower," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0049] It should be noted that in this application, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0050] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A steering knuckle forging die, characterized in that, include: The upper mold (1) and the lower mold (2) cooperate with each other, and the upper mold (1) and the lower mold (2) are provided with an upsetting cavity (3) and a pre-forging cavity (4). The upsetting cavity (3) has a first slope (5) that extends downward from the middle to both sides at one end of the long fork ear, and the pre-forging cavity (4) has a second slope (6) that is symmetrically arranged at one end of the long fork ear in the upper and lower parts, which is inclined away from the pre-forging cavity (4).

2. The steering knuckle forging die as described in claim 1, characterized in that: The upsetting cavity (3) includes an upper upsetting cavity (31) disposed on the upper mold (1) and a lower upsetting cavity (32) disposed on the lower mold (2). The first slope (5) is located on the top surface of the upper upsetting cavity (31), and the symmetrical plane between the two sides of the first slope (5) coincides with the symmetrical plane of the upper upsetting cavity (31).

3. The steering knuckle forging die as described in claim 1, characterized in that: The pre-forging cavity (4) includes an upper pre-forging cavity (41) disposed on the upper mold (1) and a lower pre-forging cavity (42) disposed on the lower mold (2). The upper pre-forging cavity (41) and the lower pre-forging cavity (42) are respectively provided with the second slope (6). The second slope (6) of the upper pre-forging cavity (41) is inclined away from the upper pre-forging cavity (41), and the second slope (6) of the lower pre-forging cavity (42) is inclined away from the lower pre-forging cavity (42).

4. The steering knuckle forging die as described in claim 1, characterized in that: The upsetting cavity (3) has a larger capacity than the pre-forging cavity (4).

5. The steering knuckle forging die as described in any one of claims 1 to 4, characterized in that: The first slope (5) has a first angle with the horizontal plane, and the second slope (6) has a second angle with the vertical direction. The first angle and the second angle are the same.

6. The steering knuckle forging die as described in any one of claims 1 to 4, characterized in that: The first slope (5) has a first angle with the horizontal plane, the size of which is 5° to 12°.

7. The steering knuckle forging die as described in any one of claims 1 to 4, characterized in that: The second slope (6) has a second included angle with the vertical direction, the size of which is 5° to 12°.

8. The steering knuckle forging die as described in claim 5, characterized in that: The size of the first included angle and the size of the second included angle are both 7°.

9. The steering knuckle forging die as described in claim 2, characterized in that: The edges of the upper upsetting cavity (31) and the lower upsetting cavity (32) are both provided with arc-shaped chamfers (7).

10. The steering knuckle forging die as described in claim 3, characterized in that: The edges of the upper pre-forging cavity (41) and the lower pre-forging cavity (42) are provided with arc-shaped chamfers (7), and the surface roughness values ​​of the upper pre-forging cavity (41) and the lower pre-forging cavity (42) are less than or equal to 0.8 μm.

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