Extrusion die for metal spline shaft difficult to deform

Abstract

The invention discloses a difficult-to-deform metal spline shaft extrusion die, and belongs to the technical field of metal extrusion dies. Comprising a middle-section mold and a lower-section mold, a second shaft end cavity with an opening in the bottom is formed in an upper-section mold, and the second shaft end cavity and a middle-section mold cavity are coaxially arranged; the plurality of spline dies are detachably mounted in the spline die mounting holes; the outer mold comprises an outer mold inner cavity, and an outer mold top opening and an outer mold bottom opening on the upper side and the lower side of the outer mold inner cavity; the outer mold is detachably arranged outside the middle-section mold, the lower-section mold, the upper-section mold and the lower-section mold in a sleeving manner; the inner cavity of the outer mold is attached to the outer side walls of the middle section mold and the spline mold; the outer mold bottom plate and the bottom of the outer mold side edge are integrally formed in a circle, and a plurality of mounting holes are formed in the outer mold bottom plate. According to the difficult-to-deform metal spline shaft extrusion die, the detachable spline die is machined in a hot forging mode, replacement is convenient when the spline die is abraded, meanwhile, spline dies with different groove depths are also convenient to replace, and practicability is high.

Description

Technical Field

[0001] The invention relates to the technical field of metal extrusion dies, and more specifically to an extrusion die for a hard-to-deform metal spline shaft. Background Art

[0002] Difficult-to-deform metals refer to metal materials that have high deformation resistance and severe work hardening during processing, and are usually used in aerospace and automotive fields. Due to their physical properties, difficult-to-deform metals are usually processed by cutting, milling or forging. Existing cutting and milling methods will cause material waste when processing some difficult-to-deform metal hollow shafts due to the need to drill holes; in the casting extrusion process, the forward extrusion process also causes material waste, and the reverse extrusion process is preferred.

[0003] The spline shaft is used to transmit mechanical torque. A longitudinal keyway is set in the middle of the shaft, which can rotate synchronously with the shaft. Existing spline shafts are mostly processed by milling, grinding or cold forging, but milling and grinding will cause material waste; and during cold forging extrusion processing, the friction inside the mold is large, resulting in rapid mold scrapping, especially the part of the extrusion spline in the mold. If it is worn and deformed, it is generally necessary to replace the entire set of molds, which increases costs. Summary of the invention

[0004] In order to overcome the problems in the above-mentioned background technology, the present invention provides a difficult-to-deform metal spline shaft extrusion die, which is processed by hot forging positive and negative extrusion, and is provided with a detachable spline die, which is convenient for replacement when worn, and also convenient for replacing spline dies with different groove depths, and has strong practicality.

[0005] In order to solve the above technical problems, the technical solution of the present invention is as follows: A hard-to-deform metal spline shaft extrusion die comprises a middle section die arranged in the middle of the die as a whole, a cylindrical middle section mold cavity is arranged in the middle section die, and the middle section mold cavity is opened at both ends; a plurality of spline mold installation holes are evenly arranged on the inner wall of the middle section die; The lower mold section is detachably mounted on the lower part of the middle mold section, and a cylindrical first shaft end cavity with an opening at the top is arranged inside the lower mold section; the first shaft end cavity and the middle mold cavity are arranged coaxially; The upper mold is movably mounted on the top of the middle mold, and a second axial end cavity with an opening at the bottom is arranged inside the upper mold, and the second axial end cavity and the middle mold cavity are coaxially arranged; Spline molds, a plurality of said spline molds are detachably mounted in the installation holes of the spline molds; The outer mold includes an outer mold cavity and an outer mold top opening and an outer mold bottom opening on upper and lower sides of the outer mold cavity; the outer mold is detachably mounted on the outside of the middle mold, the lower mold, the upper mold and the lower mold; the outer mold cavity is fitted with the outer side walls of the middle mold and the spline mold; The outer mold bottom plate is integrally formed with the outer mold side bottom circle, and a plurality of mounting holes are opened on the outer mold bottom plate.

[0006] Preferably, the length of the flower piece mold mounting hole is consistent with the length of the middle section mold cavity.

[0007] Preferably, the inner diameters of the first shaft end cavity and the second shaft end cavity are consistent.

[0008] Preferably, a middle mold bottom mounting groove is also provided on the top of the lower mold, the middle mold bottom mounting groove fits the bottom of the middle mold, and the horizontal groove depth of the middle mold bottom mounting groove is equal to the inner wall thickness of the middle mold.

[0009] Preferably, the outer wall diameter of the lower mold section is consistent with the outer wall diameter of the middle mold section.

[0010] Preferably, the inner diameter of the top opening of the outer mold is smaller than the outer diameter of the middle mold; the inner wall of the top opening of the outer mold fits with the outer wall of the upper mold.

[0011] Preferably, a middle mold top mounting groove is also provided at the bottom of the upper mold, the middle mold top mounting groove is fitted with the middle mold top, and the horizontal groove depth of the middle mold top mounting groove is less than the inner wall thickness of the middle mold.

[0012] Preferably, a plurality of spline mold mounting grooves with bottoms penetrating therethrough are arranged on the inner wall of the outer mold, the outer side wall of the spline mold extends out of the outer opening of the spline mold mounting hole, and the outer side wall of the spline mold fits with the inner wall of the spline mold mounting groove.

[0013] Preferably, the first axial hole press component and the second axial hole press component are respectively arranged in the middle of the bottom of the inner wall of the first axial end cavity and in the middle of the top of the inner wall of the second axial end cavity; the first axial hole press component and the second axial hole press component are coaxially arranged with the first axial end cavity and the second axial end cavity.

[0014] Preferably, a mold opening angle is reserved at the top of the inner wall of the middle section mold, and the mold opening angle is 1°.

[0015] Compared with the prior art, the technical solution of the present invention has the following beneficial effects: The present invention provides an extrusion die for a hard-to-deform metal spline shaft, which is processed by hot forging and provided with a detachable spline die, which is convenient for replacement when worn and also convenient for replacing spline dies with different groove depths, and has strong practicality, specifically: The middle model cavity of the middle mold and the spline mold constitute the spline section of the spline shaft. The upper mold is used as an extrusion part. After the mold is closed, the workpiece is placed in the middle model cavity. At this time, the workpiece is positioned beyond the spline section in the middle model cavity. The upper mold is pressed downward through the output end of the extruder. The second shaft end cavity in the upper mold cooperates with the upper mold to form a reverse extrusion to form a first shaft section; the first shaft end cavity in the lower mold cooperates with the lower mold to form a forward extrusion to form a second shaft section; the middle model cavity cooperates with the spline shaft to form a spline shaft section to complete the extrusion molding of the spline shaft. The spline mold in the mold is detachable, which can effectively extend the service life of the spline mold. At the same time, different spline molds can be selected according to the spline groove depth of the spline shaft to improve practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 It is a schematic diagram of the overall front cross-sectional structure of the present invention; Figure 2 It is a schematic diagram of the structure of the middle section mold and the spline mold of the present invention; Figure 3 It is a schematic diagram of the top view cross-sectional structure of the installation of the middle section mold and the spline mold of the present invention; Figure 4 It is a schematic diagram of the three-dimensional structure of the lower mold of the present invention; Figure 5 It is a schematic diagram of the three-dimensional structure of the upper mold of the present invention; Figure 6 It is a schematic diagram of the three-dimensional structure of the outer mold of the present invention.

[0018] Markings in the figure: 1. Middle section mold; 11. Middle section model cavity; 12. Spline mold mounting hole; 2. Lower section mold; 21. Middle section mold bottom mounting groove; 22. First shaft end cavity; 23. First shaft hole pressing piece; 3. Upper section mold; 31. Middle section mold top mounting groove; 32. Second shaft end cavity; 33. Second shaft hole pressing piece; 4. Spline mold; 5. Outer mold; 51. Outer mold top opening; 52. Outer mold inner cavity; 53. Outer mold bottom opening; 54. Spline mold mounting groove; 6. Outer mold bottom plate. DETAILED DESCRIPTION

[0019] In order to better understand the purpose, structure and function of the present invention, the technical solution of the present invention is further described in detail below in conjunction with the accompanying drawings and specific preferred embodiments.

[0020] In the description of the present invention, it should be understood that the terms "left side", "right side", "upper part", "lower part", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. "First", "second", etc. do not indicate the importance of the parts, and therefore cannot be understood as a limitation on the present invention. The specific dimensions used in the embodiments are only for illustrating the technical solution and do not limit the scope of protection of the present invention. It is understandable to those skilled in the art that some well-known structures and their descriptions in the drawings may be omitted.

[0021] Unless otherwise clearly specified and limited, the terms "install", "set", "connect", "fix" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0022] Embodiment 1: like Figure 1 As shown, the present invention provides a difficult-to-deform metal spline shaft extrusion die, including a middle section die 1, which is arranged in the middle of the entire die, and a cylindrical middle section model cavity 11 is arranged in the middle section die 1, and the middle section model cavity 11 is opened at both ends; a plurality of spline mold mounting holes 12 are evenly arranged on the inner wall of the middle section die 1, and the length of the spline mold mounting hole 12 is adapted to the length of the spline shaft section, such as Figure 1 The bottom height of the middle and upper mold 3 is the same as the top height of the spline shaft segment.

[0023] like Figure 1 and Figure 4 As shown, the lower mold 2 can be detachably installed at the lower part of the middle mold 1, and a cylindrical first axial end cavity 22 with a top opening is arranged inside the lower mold 2; the first axial end cavity 22 and the middle model cavity 11 are coaxially arranged, and the lower mold 2 cooperates with the first axial end cavity 22 to extrude the workpiece after the mold is closed, thereby constituting positive extrusion molding.

[0024] like Figure 1 and Figure 5 As shown, the upper mold 3 is movably installed on the top of the middle mold 1, and a second axial end cavity 32 with a bottom opening is arranged inside the upper mold 3. The second axial end cavity 32 and the middle model cavity 11 are coaxially arranged. The upper mold 3 cooperates with the second axial end cavity 32 to extrude the workpiece after the mold is closed, thereby constituting reverse extrusion molding.

[0025] like Figure 2 and Figure 3As shown, the plurality of spline dies 4 are detachably mounted in the spline die mounting hole 12. The spline die 4 is radially mounted into the spline die mounting hole 12 along the middle section model cavity 11 from the outside of the middle section die 1. The spline die 4 cooperates with the middle section model cavity 11 to form the spline shaft segment of the spline shaft during extrusion.

[0026] The spline die 4 is detachable, and the spline die 4 of different sizes can be replaced to change the groove depth of the spline shaft.

[0027] like Figure 6 As shown, the outer mold 5 includes an outer mold inner cavity 52 and an outer mold top opening 51 and an outer mold bottom opening 53 on the upper and lower sides of the outer mold inner cavity 52; the outer mold 5 is detachably mounted on the outside of the middle mold 1, the lower mold 2, the upper mold 3 and the lower mold 2; the outer mold inner cavity 52 and the outer side walls of the middle mold 1 and the spline mold 4 are fitted together, and the outer mold 5 is mainly used for mold closing. When the outer mold 5 is fitted along the outer side of the upper mold 3-middle mold 1-lower mold 2 through the outer mold bottom opening 53, the upper mold 3 can be directly positioned through the outer mold top opening 51; the middle mold 1 can also be positioned by extruding the spline mold 4, and the bottom of the middle mold 1 is fixed to the lower mold 2 in the radial direction through a connection, so that the outer mold 5 is fixed as a whole, and it is also convenient to disassemble the mold.

[0028] like Figure 1 and Figure 6 As shown, the outer mold bottom plate 6 is integrally formed with the outer mold bottom plate 6 and the bottom of the side of the outer mold 5. A plurality of mounting holes are provided on the outer mold bottom plate 6 for convenient fixing on the base of the extruder.

[0029] Furthermore, if Figure 1 As shown, the length of the spline mold mounting hole 12 is consistent with the length of the middle section mold cavity 11, which can extrude the spline shaft spline groove and form openings at both ends.

[0030] Furthermore, if Figure 1 As shown, the inner diameters of the first shaft end cavity 22 and the second shaft end cavity 32 are consistent, and are suitable for extrusion casting of spline shafts of conventional shapes.

[0031] Furthermore, if Figure 1 As shown, a middle section mold bottom mounting groove 21 is also provided on the top of the lower section mold 2, and the middle section mold bottom mounting groove 21 is fitted with the bottom of the middle section mold 1, and the horizontal groove depth of the middle section mold bottom mounting groove 21 is equal to the inner wall thickness of the middle section mold 1. The setting of the middle section mold bottom mounting groove 21 can perform radial positioning of the middle section mold 1.

[0032] Furthermore, if Figure 1As shown, the outer wall diameter of the lower mold 2 is consistent with the outer wall diameter of the middle mold 1. During the mold closing process of the outer mold 5, the outer wall diameter of the outer mold 5 does not exceed the outer wall diameter of the middle mold 1 to avoid affecting the installation of the outer mold 5. The size is preferably consistent with the outer wall diameter of the outer wall of the outer mold 5 and the outer wall diameter of the middle mold 1.

[0033] Furthermore, if Figure 1 As shown, the inner diameter of the outer mold top opening 51 is smaller than the outer diameter of the middle mold 1; the inner wall of the outer mold top opening 51 fits with the outer wall of the upper mold 3, which facilitates the closing of the outer mold 5. At the same time, the outer mold top opening 51 can position the upper mold 3 in the radial direction to achieve a fixing effect.

[0034] Furthermore, if Figure 1 As shown, a middle mold top mounting groove 31 is also provided at the bottom of the upper mold 3, and the middle mold top mounting groove 31 is fitted with the top of the middle mold 1, and the horizontal groove depth of the middle mold top mounting groove 31 is less than the inner wall thickness of the middle mold 1. The middle mold top mounting groove 31 can radially position the top of the upper mold 3 to achieve a fixing effect.

[0035] Furthermore, if Figure 6 As shown, the inner wall of the outer mold 5 is provided with a plurality of spline mold mounting grooves 54 with the bottom penetrating therethrough, the outer wall of the spline mold 4 extends out of the outer opening of the spline mold mounting hole 12, and the outer wall of the spline mold 4 fits with the inner wall of the spline mold mounting groove 54. In order to limit the axis of the outer mold 5 and prevent the outer mold 5 from rotating along its axis, the spline mold mounting hole 12 is provided so that the protruding part of the spline mold 4 can be installed in the spline mold mounting groove 54 for limiting the axis.

[0036] Furthermore, if Figure 4 As shown, the first shaft hole pressing part 23 and the second shaft hole pressing part 33 are respectively arranged in the middle of the bottom of the inner wall of the first shaft end cavity 22 and in the middle of the top of the inner wall of the second shaft end cavity 32; the first shaft hole pressing part 23 and the second shaft hole pressing part 33 are coaxially arranged with the first shaft end cavity 22 and the second shaft end cavity 32. The first shaft hole pressing part 23 and the second shaft hole pressing part 33 are arranged to extrude holes at the two shaft end ports, and there is no need to perform subsequent hole drilling. Only internal threads need to be turned later, thereby improving production efficiency.

[0037] Furthermore, if Figure 1 As shown, a mold opening angle is reserved at the top of the inner wall of the middle section mold 1, and the mold opening angle is 1°. Setting the mold opening angle facilitates demoulding.

[0038] The specific working principle of the present invention will be described below: The lower mold 2 is placed on the base and can be fixed through the mounting holes opened on the lower mold 2; the middle mold 1 is mounted on the middle mold 1 through the mounting groove 21 at the bottom of the middle mold, so that the two are radially positioned; the spline mold 4 of appropriate size is installed through the spline mold mounting hole 12, and then the outer mold 5 is inserted into the outer side of the middle mold 1 and the upper mold 3 through the opening 53 at the bottom of the outer mold. During this process, the outer side of the spline mold 4 slides in the spline mold mounting groove 54 to axially position the outer mold 5 until the outer mold bottom plate 6 at the bottom of the outer mold 5 fits the upper surface of the extruder, and the outer mold bottom plate 6 is fixed with bolts so that the outer mold The mold 5 positions the middle mold 1 and the lower mold 2; during extrusion, the workpiece is placed from the top of the middle mold 1, and the workpiece is extruded by pressing down the upper mold 3 connected to the extruder. When the workpiece is continuously compressed, the lower mold 2 cooperates with the first shaft end cavity 22 to extrude the workpiece after the mold is closed, forming a positive extrusion molding; the upper mold 3 cooperates with the second shaft end cavity 32 to extrude the workpiece after the mold is closed, forming a reverse extrusion molding; the spline mold 4 cooperates with the middle model cavity 11 to form the spline shaft section of the spline shaft during extrusion; finally, when the middle mold bottom mounting groove 21 of the upper mold 3 fits the upper end surface of the middle mold 1, the internal workpiece is formed.

[0039] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A hard-to-deform metal spline shaft extrusion die, characterized in that: The middle section mold (1) is provided in the middle of the whole mold, a cylindrical middle section mold cavity (11) is provided in the middle section mold (1), and the middle section mold cavity (11) is opened at both ends; a plurality of flower piece mold installation holes (12) are evenly arranged around the inner wall of the middle section mold (1); The lower mold section (2) is detachably mounted on the lower part of the middle mold section (1); a cylindrical first shaft end cavity (22) with a top opening is arranged inside the lower mold section (2); the first shaft end cavity (22) and the middle mold cavity (11) are coaxially arranged; The upper mold (3) is movably mounted on the top of the middle mold (1), and a second axial end cavity (32) with a bottom opening is arranged inside the upper mold (3), and the second axial end cavity (32) and the middle mold cavity (11) are coaxially arranged; A spline mold (4), wherein a plurality of the spline molds (4) are detachably mounted in the spline mold mounting hole (12); The outer mold (5) comprises an outer mold inner cavity (52) and an outer mold top opening (51) and an outer mold bottom opening (53) on upper and lower sides of the outer mold inner cavity (52); the outer mold (5) is detachably mounted on the outside of the middle mold (1), the lower mold (2), the upper mold (3) and the lower mold (2); the outer mold inner cavity (52) and the outer side walls of the middle mold (1) and the spline mold (4) are fitted together; The outer mold bottom plate (6) is integrally formed with the outer mold bottom plate (6) and the bottom of the side of the outer mold (5), and a plurality of mounting holes are provided on the outer mold bottom plate (6).

2. The hard-to-deform metal spline shaft extrusion die according to claim 1, characterized in that: The length of the flower piece mold mounting hole (12) is consistent with the length of the middle section mold cavity (11).

3. The hard-to-deform metal spline shaft extrusion die according to claim 1, characterized in that: The first shaft end cavity (22) and the second shaft end cavity (32) have the same inner diameter size.

4. The hard-to-deform metal spline shaft extrusion die according to claim 1, characterized in that: The top of the lower mold (2) is also provided with a middle mold bottom mounting groove (21), the middle mold bottom mounting groove (21) and the bottom of the middle mold (1) are fitted together, and the horizontal groove depth of the middle mold bottom mounting groove (21) is equal to the inner wall thickness of the middle mold (1).

5. The difficult-to-deform metal spline shaft extrusion die according to claim 4, characterized in that: The outer wall diameter of the lower mold (2) is consistent with the outer wall diameter of the middle mold (1).

6. The hard-to-deform metal spline shaft extrusion die according to claim 1, characterized in that: The inner diameter of the top opening (51) of the outer mold is smaller than the outer diameter of the middle mold (1); the inner wall of the top opening (51) of the outer mold is in close contact with the outer wall of the upper mold (3).

7. The hard-to-deform metal spline shaft extrusion die according to claim 6, characterized in that: The bottom of the upper mold (3) is also provided with a middle mold top installation groove (31), the middle mold top installation groove (31) and the top of the middle mold (1) are fitted together, and the horizontal groove depth of the middle mold top installation groove (31) is less than the inner wall thickness of the middle mold (1).

8. The hard-to-deform metal spline shaft extrusion die according to claim 1, characterized in that: The inner wall of the outer mold (5) is provided with a plurality of spline mold installation grooves (54) with the bottoms penetrating therethrough; the outer wall of the spline mold (4) extends out of the outer opening of the spline mold installation hole (12); and the outer wall of the spline mold (4) fits the inner wall of the spline mold installation groove (54).

9. The hard-to-deform metal spline shaft extrusion die according to claim 1, characterized in that: A first shaft hole pressing piece (23) and a second shaft hole pressing piece (33) are respectively arranged in the middle of the bottom of the inner wall of the first shaft end cavity (22) and in the middle of the top of the inner wall of the second shaft end cavity (32); the first shaft hole pressing piece (23) and the second shaft hole pressing piece (33) are coaxially arranged with the first shaft end cavity (22) and the second shaft end cavity (32).

10. The hard-to-deform metal spline shaft extrusion die according to claim 1, characterized in that: A mold opening angle is reserved at the top of the inner wall of the middle section mold (1), and the mold opening angle is 1°.

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