Aluminum alloy knuckle forging die and forging method

Abstract

This invention discloses a forging die and forging method for aluminum alloy steering knuckles. The forging die includes a pre-forging die and a final forging die. The pre-forging die consists of an upper pre-forging die and a lower pre-forging die. The cavity of the upper pre-forging die and the corresponding cavity of the lower pre-forging die constitute a first forging cavity. The two first forging cavities are symmetrically arranged, and a first connecting area exists between them. The final forging die includes an upper final forging die and a lower final forging die. The cavity of the upper final forging die and the corresponding cavity of the lower final forging die constitute a second forging cavity. The two second forging cavities are symmetrically arranged, and a second connecting area exists between them. A stepped hole is provided on the upper final forging die above the ear portion of each upper final forging cavity, and a venting groove communicating with the stepped hole is provided on the upper end face of the upper final forging die. An auxiliary mechanism is provided within the stepped hole. This invention can effectively solve the problems of inaccurate billet positioning, incomplete forging, and die jamming, thereby improving the production efficiency and product qualification rate of aluminum alloy steering knuckles.

Description

Technical Field

[0001] This invention belongs to the technical field of aluminum alloy steering knuckle forging, specifically relating to an aluminum alloy steering knuckle forging die and forging method. Background Technology

[0002] Aluminum alloy steering knuckles are lightweight and corrosion-resistant, giving them a significant advantage in applications in new energy vehicles. Currently, aluminum alloy steering knuckles are typically manufactured using die extrusion forging to improve their strength and overall integrity.

[0003] However, steering knuckles are characterized by multi-branched, variable cross-section, three-dimensional, and asymmetrical structures, with a shape complexity coefficient generally ≤0.32, placing them in the S3-S4 level, making them typical complex or relatively complex forgings. Aluminum alloys have low plasticity and a high coefficient of friction; currently, aluminum alloy blanks shaped like hand grenades are commonly used for forging aluminum alloy steering knuckles. During pre-forging, the blank is prone to inaccurate positioning, and during final forging, incomplete molding and die jamming are common at the lugs, resulting in low production efficiency and low product qualification rates for aluminum alloy steering knuckles. Summary of the Invention

[0004] In view of the above-mentioned shortcomings of the existing technology, the purpose of this invention is to provide an aluminum alloy steering knuckle forging die and forging method, which can effectively solve the problems of inaccurate billet positioning, incomplete forging and die jamming, and improve the production efficiency and product qualification rate of aluminum alloy steering knuckles.

[0005] The technical solution of this invention is implemented as follows:

[0006] An aluminum alloy steering knuckle forging die includes a pre-forging die and a final forging die.

[0007] The pre-forging die consists of an upper pre-forging die and a lower pre-forging die arranged vertically. The lower end face of the upper pre-forging die has two upper pre-forging die cavities, and the upper end face of the lower pre-forging die has two lower pre-forging die cavities. The upper pre-forging die cavities and the corresponding lower pre-forging die cavities constitute the first forging cavity. The two first forging cavities are symmetrically arranged and there is a first connecting area between the two first forging cavities.

[0008] The final forging die includes an upper final forging die and a lower final forging die arranged vertically. The lower end face of the upper final forging die has two upper final forging die cavities, and the upper end face of the lower final forging die has two lower final forging die cavities. The upper final forging die cavities and the corresponding lower final forging die cavities constitute a second forging cavity. The two second forging cavities are symmetrically arranged and there is a second connecting area between the two second forging cavities.

[0009] Each final forging die has a stepped hole above the ear of the die cavity, and a venting groove communicating with the stepped hole is provided on the upper end face of the final forging die; an auxiliary mechanism is provided in the stepped hole to realize venting, lubrication and assisted demolding during the final forging process.

[0010] Furthermore, the central axis of the stepped hole is vertically arranged and is composed of a first through hole located at the bottom, a second through hole located at the middle, and a third through hole for connecting the first through hole and the second through hole. The third through hole is a trumpet hole with a smaller bottom and a larger top, and the diameter of the lower end of the third through hole corresponds to that of the first through hole, while the diameter of the upper end is smaller than that of the second through hole.

[0011] Furthermore, the auxiliary mechanism includes a support plate, an exhaust pipe, and a compression spring. The support plate is horizontally disposed within the second through hole and its size is larger than the diameter of the third through hole but smaller than the diameter of the second through hole. The exhaust pipe is smaller than the diameter of the first through hole and is vertically disposed at the center of the support plate, with its lower end passing through the support plate and inserted into the first through hole. The compression spring is sleeved on the exhaust pipe above the support plate.

[0012] This invention also provides a method for forging an aluminum alloy steering knuckle, which uses the aforementioned aluminum alloy steering knuckle forging die to forge the aluminum alloy steering knuckle, specifically including the following steps:

[0013] S1: Place the preheated dumbbell-shaped billet on the lower pre-forging die, so that the billet is symmetrically positioned above the two lower pre-forging die cavities; then place the upper pre-forging die on the billet, and make the upper pre-forging die cavity correspond to the lower pre-forging die cavity, and then perform pre-forging to obtain the pre-forged part;

[0014] S2: Turn the pre-forged part over and place it in the lower die cavity of the final forging die. Place the upper die of the final forging die above the pre-forged part and make the upper die cavity of the final forging die correspond to the lower die cavity of the final forging die. Then place the auxiliary mechanism in the stepped hole, and place the die holder plate on the upper end face of the upper die of the final forging die. Then perform the final forging to obtain the aluminum alloy steering knuckle.

[0015] Furthermore, the billet is obtained from bar stock by roll forging or wedge cross rolling.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] 1. The forging die described in this invention is used to forge aluminum alloy steering knuckles, allowing for the forging of two pieces at a time, which can effectively improve production efficiency. At the same time, this invention uses dumbbell-shaped billets for forging, which can utilize the original structure of the pre-forging die to effectively position the billets, ensuring positioning accuracy, improving the forging quality of aluminum alloy steering knuckles, and increasing the product qualification rate.

[0018] 2. This invention incorporates an auxiliary mechanism within the final forging die. This effectively removes air from the lugs of the final forging die cavity during the final forging process, preventing air trapping in the die, facilitating metal flow, and ensuring complete filling of the final forging die cavity. This improves the forging quality of the aluminum alloy steering knuckle and increases the product qualification rate. Furthermore, it facilitates the flow of aluminum alloy forging lubricating oil from the gaps to the lugs of the final forging die cavity, reducing metal flow resistance and promoting forging formation. After forging is completed, the final forging die moves upward, compressing the spring to release its elastic force and compressing the exhaust pipe to move downward, applying a downward pushing force to the forging and promoting demolding. Simultaneously, aluminum alloy forging lubricating oil flows from the gap between the exhaust pipe and the first through hole to the contact surface of the forging in the final forging die cavity, reducing demolding friction resistance and further promoting demolding. Attached Figure Description

[0019] Figure 1 - A cross-sectional schematic diagram of the forging die of the present invention.

[0020] Figure 2 - Schematic diagram of pre-forging die positioning.

[0021] Figure 3 - A schematic diagram of the auxiliary mechanism.

[0022] Figure 4 - A schematic diagram of airflow and aluminum alloy forging lubricating oil flow during the final forging process.

[0023] Figure 5 - A schematic diagram of the completed molding process.

[0024] Wherein: 1-Pre-forging upper die; 2-Pre-forging lower die; 31-Pre-forging part I; 32-Pre-forging part II; 33-First connecting skin; 4-Final forging upper die; 41-Stepped hole; 42-Ear; 43-Exhaust groove; 5-Final forging lower die; 61-Final forging part I; 62-Final forging part II; 63-Second connecting skin; 7-Auxiliary mechanism; 71-Compression spring; 72-Support plate; 721-Exhaust pipe; 73-Aluminum alloy forging lubricating oil; 8-Bill. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, 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 a part of the embodiments of the present invention, not all of them. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to represent selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0026] It should be noted that similar reference numerals and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the figures, or the orientation or positional relationship commonly used when the product is in use. They are only for the convenience of describing the invention 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. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance. In addition, the terms "horizontal," "vertical," etc., do not indicate that the component is required to be absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted. In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" 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; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0027] Due to the multi-branched, variable cross-section, three-dimensional, and asymmetrical structural characteristics of steering knuckles, their shape complexity coefficient is generally ≤0.32, falling into the S3-S4 level, making them typical complex or relatively complex forgings. Aluminum alloys have low plasticity and a high coefficient of friction. Currently, aluminum alloy steering knuckles are mostly produced by forging grenade-shaped aluminum alloy billets, allowing only one steering knuckle to be forged at a time, resulting in low production efficiency. Furthermore, the grenade-shaped billets are prone to inaccurate positioning during pre-forging, affecting forging quality and leading to a low product qualification rate. Additionally, incomplete molding is easily observed at the lugs during final forging, and mold jamming is a common problem during demolding, further contributing to low production efficiency and a low product qualification rate for aluminum alloy steering knuckles.

[0028] Based on this, the present invention provides an aluminum alloy steering knuckle forging die, see details below. Figures 1-5 This includes pre-forging dies and final forging dies. Figure 1 In the middle, (a) is the pre-forging die and (b) is the final forging die, which are used for the pre-forging and final forging of aluminum alloy steering knuckles, respectively.

[0029] The pre-forging mold consists of an upper pre-forging mold 1 and a lower pre-forging mold 2 arranged vertically. The lower end face of the upper pre-forging mold 1 has two upper pre-forging mold cavities, and the upper end face of the lower pre-forging mold 2 has two lower pre-forging mold cavities. The upper pre-forging mold cavities and the corresponding lower pre-forging mold cavities constitute the first forging cavity. The two first forging cavities are symmetrically arranged and there is a first connecting area between the two first forging cavities.

[0030] Here, two upper pre-forging die cavities and two lower pre-forging die cavities are symmetrically arranged. The two upper pre-forging die cavities and their corresponding lower pre-forging die cavities respectively form two first forging cavities. After the upper and lower pre-forging dies are closed for pre-forging, a pre-forging part (pre-forging part I 31 and pre-forging part II 32) is obtained in each of the two first forging cavities. The two pre-forging parts are connected by a first connecting skin 33. In this way, two pre-forging parts can be pre-forged in one operation, which can effectively improve production efficiency.

[0031] The final forging die includes an upper final forging die 4 and a lower final forging die 5 arranged vertically. The lower end face of the upper final forging die 4 has two upper final forging die cavities, and the upper end face of the lower final forging die 5 has two lower final forging die cavities. The upper final forging die cavities and the corresponding lower final forging die cavities constitute a second forging cavity. The two second forging cavities are symmetrically arranged and there is a second connecting area between the two second forging cavities.

[0032] Each final forging die 4 has a stepped hole 41 above the ear of the final forging die cavity, and a venting groove 43 communicating with the stepped hole 41 is provided on the upper end face of the final forging die 5. An auxiliary mechanism is provided in the stepped hole 41 to realize venting, lubrication and assisted demolding during the final forging process. Specifically, the central axis of the stepped hole 41 is vertically arranged and is composed of a first through hole at the bottom, a second through hole at the middle, and a third through hole for connecting the first through hole and the second through hole. The third through hole is a flared hole with a smaller bottom and a larger top, and the diameter of the lower end of the third through hole corresponds to the diameter of the first through hole, while the diameter of the upper end is smaller than the diameter of the second through hole. Meanwhile, the auxiliary mechanism includes a support plate 72, an exhaust pipe 721, and a compression spring 71. The support plate 72 is horizontally arranged in the second through hole and its size is larger than the diameter of the third through hole but smaller than the diameter of the second through hole. The exhaust pipe 721 is smaller than the diameter of the first through hole. The exhaust pipe 721 is vertically arranged in the center of the support plate 72 and its lower end passes through the support plate 72 and is inserted into the first through hole. The compression spring 71 is sleeved on the exhaust pipe 721 above the support plate 72.

[0033] Here, the support plate is larger than the diameter of the third through hole but smaller than the diameter of the second through hole, allowing the support plate to move only within the second through hole, while maintaining a certain gap between the support plate and the inner wall corresponding to the second through hole. The exhaust pipe is smaller than the diameter of the first through hole, also creating a gap between the exhaust pipe and the inner wall corresponding to the first through hole. After pre-forging, the pre-forged part needs to be rotated 180°, with its upper end facing down and placed into the lower die cavity of the final forging, while its lower end faces up. After final forging by the upper and lower dies, two final forging cavities yield one final forging (final forging I 61 and final forging II 62), connected by a second connecting piece 63. In practical applications, the inner diameter of the exhaust pipe is 3-5 mm.

[0034] Before final forging, the support plate is located at the bottom of the second through hole, and the lower end of the exhaust pipe passes through the first through hole and is inserted into the cavity of the final forging upper die. Aluminum alloy forging lubricating oil is filled into the second through hole above the support plate, and a die holder pad is placed on the upper end face of the final forging upper die. The lower end face of the compression spring contacts the support plate, and the upper end face contacts the die holder pad.

[0035] During the final forging process, the upper die moves downwards, creating a closed space at the lug of the upper die cavity. Air at the lug is then discharged through the exhaust pipe and exhaust groove, preventing air from accumulating in the die (see...). Figure 4 (See the left figure). This facilitates metal flow and ensures complete filling of the final forging die cavity, improving the forging quality of the aluminum alloy steering knuckle and increasing the product qualification rate. Furthermore, it allows for the flow of aluminum alloy forging lubricating oil from the gaps to the lugs of the final forging die cavity, reducing metal flow resistance and promoting forging formation (see...). Figure 4 (The image on the right).

[0036] After the forging is formed, the final forging die moves upward, the compression spring releases its elastic force, and the compression exhaust pipe moves downward, applying a downward pushing force to the forging and causing it to demold. At the same time, aluminum alloy forging lubricating oil flows from the gap between the exhaust pipe and the first through hole to the contact surface of the forging in the final forging die cavity, reducing the demolding friction resistance and further promoting the demolding of the forging.

[0037] Thus, using the forging die described in this invention to forge two aluminum alloy steering knuckles in one operation can effectively improve production efficiency, while also ensuring that the high lugs of the forging are fully filled, guaranteeing forging quality, and improving product qualification rate; in addition, it can also effectively solve the problem of die jamming and improve production efficiency.

[0038] This invention provides a method for forging an aluminum alloy steering knuckle, which uses the aforementioned aluminum alloy steering knuckle forging die to forge the aluminum alloy steering knuckle, specifically including the following steps:

[0039] S1: Place the preheated dumbbell-shaped billet on the lower pre-forging die, so that the billet is symmetrically positioned above the two lower pre-forging die cavities; then place the upper pre-forging die on the billet, and make the upper pre-forging die cavity correspond to the lower pre-forging die cavity, and then perform pre-forging to obtain the pre-forged part.

[0040] The billet here is obtained from bar stock through roll forging or wedge cross rolling. Compared with the existing technology that uses grenade-shaped billets, the dumbbell-shaped billet can make full use of the original structure of the pre-forging die to support and position the billet. The positioning structure here is a conformal positioning structure 21, which can achieve precise positioning of the billet, avoid the final billet from moving during the forging process, effectively improve the forming quality of the pre-forged parts, and thus improve the product qualification rate of aluminum alloy steering knuckles.

[0041] S2: Flip the pre-forged part over and place it in the lower cavity of the final forging die. Place the upper final forging die above the pre-forged part, ensuring the upper cavity aligns with the lower cavity. Place an auxiliary mechanism in the stepped hole, and then place a die holder plate on the upper surface of the upper final forging die. Perform final forging to obtain the aluminum alloy steering knuckle. Specifically, after placing the upper final forging die above the pre-forged part, first place a support plate and an exhaust pipe (the support plate and exhaust pipe are a combination, with the exhaust pipe and support plate sealed and fixedly connected) in the stepped hole. Then, place a compression spring on the support plate and fill the stepped hole with aluminum alloy forging lubricating oil. Place the die holder plate, and finally perform final forging.

[0042] The final forging process is as follows: the upper die moves downward, forming a closed space at the lug of the die cavity until the forging is filled. Air at the lug is discharged through the vent pipe and vent groove, preventing air from accumulating in the die and promoting forging formation. Simultaneously, as the upper die moves downward, metal flows to the vent pipe until the forging is filled. The vent pipe then moves upward, compressing the compression spring. During this process, aluminum alloy forging lubricating oil flows from the gap to the lug of the die cavity, further promoting forging formation.

[0043] After the forging is formed, the final forging die moves upward, the compression spring releases its elastic force, and the compression exhaust pipe moves downward, causing the forging to be demolded. At the same time, aluminum alloy forging lubricating oil flows from the gap between the exhaust pipe and the first through hole to the contact surface of the forging in the final forging die cavity, reducing the demolding force and further promoting the demolding of the forging.

[0044] Finally, it should be noted that the above embodiments of the present invention are merely illustrative examples and not intended to limit the implementation of the invention. Those skilled in the art can make other variations and modifications based on the above description. It is impossible to exhaustively list all possible implementations here. All obvious variations or modifications derived from the technical solutions of this invention are still within the scope of protection of this invention.

Claims

1. A forging die for an aluminum alloy steering knuckle, characterized in that, Including pre-forging dies and final forging dies; The pre-forging die is composed of an upper pre-forging die and a lower pre-forging die arranged vertically. The lower end face of the upper pre-forging die has two upper pre-forging die cavities, and the upper end face of the lower pre-forging die has two lower pre-forging die cavities. The upper pre-forging die cavities and the corresponding lower pre-forging die cavities constitute the first forging cavity. The two first forging cavities are symmetrically arranged and there is a first connecting area between the two first forging cavities. The final forging die includes an upper final forging die and a lower final forging die arranged vertically. The lower end face of the upper final forging die has two upper final forging die cavities, and the upper end face of the lower final forging die has two lower final forging die cavities. The upper final forging die cavities and the corresponding lower final forging die cavities constitute a second forging cavity. The two second forging cavities are symmetrically arranged and there is a second connecting skin area between the two second forging cavities. Each final forging die has a stepped hole above the ear of the die cavity, and a venting groove communicating with the stepped hole is provided on the upper end face of the final forging die; an auxiliary mechanism is provided in the stepped hole to realize venting, lubrication and assisted demolding during the final forging process.

2. The aluminum alloy steering knuckle forging die according to claim 1, characterized in that, The stepped hole has a vertically oriented central axis and is composed of a first through hole at the bottom, a second through hole at the top, and a third through hole for connecting the first and second through holes. The third through hole is a funnel-shaped hole with a smaller bottom and a larger top, and the diameter of the lower end of the third through hole corresponds to that of the first through hole, while the diameter of the upper end is smaller than that of the second through hole.

3. The aluminum alloy steering knuckle forging die according to claim 2, characterized in that, The auxiliary mechanism includes a support plate, an exhaust pipe, and a compression spring. The support plate is horizontally arranged in the second through hole and its size is larger than the diameter of the third through hole but smaller than the diameter of the second through hole. The exhaust pipe is smaller than the diameter of the first through hole. The exhaust pipe is vertically arranged in the center of the support plate and its lower end passes through the support plate and is inserted into the first through hole. The compression spring is sleeved on the exhaust pipe above the support plate.

4. A method for forging an aluminum alloy steering knuckle, characterized in that, The forging of aluminum alloy steering knuckles using an aluminum alloy steering knuckle forging die according to any one of claims 1-3 specifically includes the following steps: S1: Place the preheated dumbbell-shaped billet on the lower pre-forging die, so that the billet is symmetrically positioned above the two lower pre-forging die cavities; then place the upper pre-forging die on the billet, and make the upper pre-forging die cavity correspond to the lower pre-forging die cavity, and then perform pre-forging to obtain the pre-forged part; S2: Turn the pre-forged part over and place it in the lower die cavity of the final forging die. Place the upper die of the final forging die above the pre-forged part and make the upper die cavity of the final forging die correspond to the lower die cavity of the final forging die. Then place the auxiliary mechanism in the stepped hole, and place the die holder plate on the upper end face of the upper die of the final forging die. Then perform the final forging to obtain the aluminum alloy steering knuckle.

5. The forging method for an aluminum alloy steering knuckle according to claim 4, characterized in that, The billet is obtained from bar stock by roll forging or wedge rolling.

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