CN105642696B - A kind of wedge shape with Surface Texture becomes the porous lubrication splined shaft extrusion die of modulus - Google Patents

Abstract

A wedge-shaped variable modulus porous lubricated spline shaft extrusion die with surface texture, including the extrusion die and its externally connected prestressing die fixing sleeve, the prestressing die fixing sleeve and the extrusion die are interference fit, pre-stressed There is a sealing ring at the joint between the stress die fixing sleeve and the extrusion die. The extrusion die is divided into an upper bevel section, a middle forming section, and a wedge-shaped transition section. The tooth modulus of the wedge-shaped transition section gradually increases from bottom to top, and the tooth thickness Decrease gradually from bottom to top, and the tooth height gradually decreases from bottom to top. Laser scoring is performed on the slopes of the middle forming section and the wedge-shaped transition section to form surface texture to reduce friction. The present invention changes the shape of the mold tooth The modulus is used to control the metal flow during the forming process, which improves the yield of the extruded spline shaft.

Description

A wedge-shaped variable modulus porous lubricated spline shaft extrusion die with surface texture

technical field

The invention belongs to the technical field of extrusion molding dies, in particular to a wedge-shaped variable modulus porous lubricating spline shaft extrusion die with surface texture.

Background technique

Splines have been widely used in aerospace, automobile industry, petrochemical and other industrial sectors, so splines are required to have high precision and mechanical properties. Forming spline shafts by cold extrusion can significantly improve processing efficiency, and forming The spline hardness is relatively high. Cold extrusion forming is a precision plastic volume forming technology. It refers to putting the metal blank into the mold or clamping mechanism in a cold state. The workpiece blank is formed in the mold cavity to obtain extrusions with required dimensions and mechanical properties. Cold extrusion processing is to control the flow of metal through the mold, so as to realize the large transfer of metal volume to form parts, but the commonly used extrusion dies generally have the disadvantages of simple structure, large stress and high friction, especially the extrusion flower. For tooth-shaped parts such as keys, the dimensional accuracy is not high. Due to the high extrusion force, it is difficult to control the metal flow. Most of the metal is not used to form the tooth shape but moves with the mold, resulting in metal accumulation and the bottom of the spline shaft. Folding is easy to occur, which seriously affects the yield of the extruded spline shaft.

Contents of the invention

In order to overcome the above-mentioned shortcomings of the prior art, the purpose of the present invention is to provide a wedge-shaped variable modulus porous lubricated spline shaft extrusion die with surface texture, which can control the deformation during the forming process by changing the modulus of the die tooth profile. Metal flow improves the yield of extruded spline shafts.

In order to achieve the above object, the technical scheme adopted in the present invention is:

A wedge-shaped variable modulus porous lubricated spline shaft extrusion die with surface texture, including an extrusion die 2 and a prestressing die fixing sleeve 1 connected externally, the prestressing die fixing sleeve 1 and the extrusion die 2 are connected Overfit fit, a sealing ring 3 is installed at the joint between the prestressing die fixing sleeve 1 and the extrusion die 2. The extrusion die 2 is divided into an upper bevel section I, a middle forming section II, and a wedge-shaped transition section III. The sealing ring 3 is a metal seal Gasket, the material is pure copper.

The inclination angle α of the upper bevel section I of the extrusion die 2 is 45 degrees to buffer the stress on the extrusion die 2 .

The wedge-shaped transition section III tooth modulus of the extrusion die 2 gradually increases from bottom to top, the tooth thickness gradually increases from bottom to top, and the tooth height gradually increases from bottom to top, so that the extrusion die 2 teeth Both the axial and radial directions of the high part and tooth bottom part are wedge-shaped.

The tooth bottoms of the middle forming section II of the extrusion die 2 and the wedge-shaped transition section III are enlarged in size relative to the formed workpiece, and a gap is reserved with the formed workpiece, and 3-5 small oil holes arranged longitudinally are processed on each tooth bottom position Ⅳ. Prestressing die fixing sleeve 1 processes the oil cavity relative to the oil hole. During the processing, lubricating oil is filled into the small oil hole from the prestressing die fixing sleeve 1 oil cavity IV. The oil pressure is less than 5MPa, making the extrusion die 2 more lubricated full.

Laser scoring is performed on the slopes of the middle forming section II and the wedge-shaped transition section III of the extrusion die 2 to form a surface texture to reduce friction.

The entrance chamfer β at the bottom of the extrusion die 2 is consistent with the front chamfer of the processed shaft and rod parts, and is at least 30 degrees.

The present invention has the following advantages:

1. The wedge-shaped transition section III of the extrusion die 2 adopts the method of variable modulus to form the spline, which can significantly reduce the forming force. Under the condition that the number of teeth remains unchanged, the increase of the modulus means that the tooth shape of the die is increased. The diameter of the indexing circle, the diameter increases and the tooth height increases, so that the forming part of the workpiece increases from small to large during processing, and the axial force it receives also increases from small to large, thereby reducing the spline shaft during processing. The phenomenon of material accumulation in the machine reduces the resistance of forming.

2. The tooth shape of extrusion die 2 adopts the method of tooth thickness increasing from bottom to top, which can control the metal flow, so that more metal gradually flows to the top of the tooth to fill the tooth shape during processing, and the phenomenon of metal accumulation is reduced, reducing the Forming resistance, less metal accumulation avoids the folding phenomenon of the forming end, and improves the yield of the spline shaft.

3. Small oil holes IV are processed at the tooth bottom of the extrusion die 2, which improves the lubrication conditions. During the forming process, the metal does not completely fill into the tooth-shaped cavity of the extrusion die 2, but leaves a certain gap through which the lubricating oil can pass. The small oil hole IV enters the cavity of the extrusion die 2, so that the extrusion die 2 is fully lubricated during the forming process, and the frictional resistance is reduced.

4. The surface of the extrusion die 2 is scored by laser to form a surface texture, and a reasonable surface texture can reduce friction. The dent can be filled with lubricating oil to form a lubricating oil film, combined with the lubricating oil hole, the lubricating oil film can be kept on the surface of the extrusion die 2 during the forming process, significantly reducing friction.

5. The entrance chamfer at the bottom of the extrusion die 2 is consistent with the front chamfer of the processed shaft and rod parts. Processing the front chamfer of the workpiece can reduce the material redundancy at the top of the workpiece and avoid excessive axial forming force at the initial stage of forming.

Description of drawings

Fig. 1 is an overall view of the present invention.

FIG. 2 is a top view of FIG. 1 .

Fig. 3 is a bottom view of Fig. 1 .

Fig. 4 is a sectional view of A-A section in Fig. 2 .

Fig. 5 is a sectional view of the B-B section in Fig. 2 .

Figure 6 is a partial view of the tooth shape.

detailed description

The present invention will be described in detail below in conjunction with the accompanying drawings.

Referring to Figure 1, Figure 2, Figure 3, Figure 4 and Figure 5, a wedge-shaped variable modulus porous lubricated spline shaft extrusion die with surface texture, including extrusion die 2 and its externally connected prestressing die Set 1, the prestressing die fixing sleeve 1 and the extrusion die 2 are interference fit, the interference is 0.25mm, the sealing ring 3 is installed at the joint between the prestressing die fixing sleeve 1 and the extrusion die 2, and the sealing ring 3 is metal Gasket, the material is pure copper.

Referring to Figures 4 and 5, the extrusion die 2 is provided with an upper bevel section I, a middle forming section II, and a wedge-shaped transition section III.

Referring to Fig. 2 and Fig. 3, the tooth modulus of the wedge-shaped transition section III of the extrusion die 2 gradually increases from bottom to top, the tooth thickness gradually increases from bottom to top, and the tooth height gradually increases from bottom to top , so that both the axial and radial directions of the tooth height and tooth bottom of the extrusion die 2 are wedge-shaped.

Referring to Fig. 4 and Fig. 5, the inclination angle α of the upper bevel section I of the extrusion die 2 is 45 degrees to buffer the stress on the die.

Referring to Fig. 4, Fig. 5 and Fig. 6, the tooth bottom position of the middle forming section II of the extrusion die 2 and the wedge-shaped transition section III are enlarged in size relative to the formed workpiece, and there is a gap with the formed workpiece, and each tooth bottom position is processed There are 3-5 small oil holes IV arranged longitudinally, and the position of the relatively small oil hole IV on the prestressing mold fixing sleeve 1 is used to process the oil cavity, and the lubricating oil is filled into the tiny oil holes from the oil cavity of the prestressing mold fixing sleeve 1 Ⅳ, the oil pressure is less than 5MPa, so that the extrusion die 2 is more fully lubricated.

The slopes of the forming section II in the middle of the extrusion die 2 and the wedge-shaped transition section III are laser scored to form a surface texture to reduce friction, and a reasonable surface texture can reduce friction. The dent can be filled with lubricating oil to form a lubricating oil film, combined with the lubricating oil hole, the lubricating oil film can be kept on the surface of the mold during the forming process, significantly reducing friction.

Referring to Fig. 4 and Fig. 5, the entrance chamfer β at the bottom of the extrusion die 2 is consistent with the front chamfer of the processed shaft and rod parts, and is at least 30 degrees.

Working principle of the present invention is:

During processing, the workpiece blank is placed at the bottom of the extrusion die 2, and the extrusion die 2 moves toward the workpiece blank so that the workpiece blank enters from the bottom. The prestressing die fixing sleeve 1 ensures the strength of the extrusion die 2, and the upper bevel section of the extrusion die 2 Ⅰ buffer the stress on the mold.

Under the condition that the wedge-shaped transition section III of the extrusion die 2 keeps the number of teeth constant, the increase of the modulus means that the diameter of the pitch circle of the tooth shape of the extrusion die 2 is increased. The diameter increases and the tooth height increases, so that the workpiece The forming part changes from small to large during the processing process, and the axial force it receives also changes from small to large, thereby reducing the material accumulation phenomenon of the spline shaft during the processing process and reducing the forming resistance. The tooth bottoms of the forming section II in the middle of the extrusion die 2 and the wedge-shaped transition section III are appropriately enlarged in size, and a certain gap is reserved with the formed workpiece.

The small oil holes IV arranged in the longitudinal direction are processed on the bottom of each tooth. During the processing, the oil holes are filled with lubricating oil to make the mold more fully lubricated. The wedge-shaped transition section III adopts the method of tooth thickness increasing from bottom to top, which can control the metal Flow, so that more metal gradually flows to the top of the tooth to fill the tooth shape during processing, the phenomenon of metal accumulation is reduced, and the resistance of forming is reduced. Less metal accumulation avoids the folding phenomenon of the forming end and improves the spline shaft. Yield.

The surface of the extrusion die 2 is scored by laser to form a surface texture. A reasonable surface texture can reduce friction, and the dent can be filled with lubricating oil to form a lubricating oil film. Combined with lubricating oil holes, the lubricating oil film can Can be kept on the surface of the extrusion die 2, significantly reducing friction.

Claims (2)

1. it is a kind of with Surface Texture wedge shape become modulus it is porous lubrication splined shaft extrusion die, including extrusion die (2) and its The pre-stress die fixed cover (1) of external connection, it is characterised in that：Pre-stress die fixed cover (1) and extrusion die (2) were It is full of cooperation, with being equipped with sealing ring (3) at extrusion die (2) cooperation, extrusion die (2) is divided into pre-stress die fixed cover (1) Portion oblique angle section (I), middle part shaped segment (II), wedge-shaped changeover portion (III), sealing ring (3) are metallic packing, and material is fine copper；

Upper bevel section (I) inclination alpha of described extrusion die (2) is 45 degree, to buffer stress suffered by extrusion die (2)；

Wedge-shaped changeover portion (III) the tooth form modulus of described extrusion die (2) gradually increases from bottom to top, transverse tooth thickness from bottom to top by Cumulative big, tooth height gradually increases from bottom to top, makes axially and radially presenting for extrusion die (2) tooth high-order bit and bottom of the tooth position Wedge shape；

The middle part shaped segment (II) of described extrusion die (2) is with the bottom of the tooth position of wedge-shaped changeover portion (III) relative to Forming Workpiece Up-sizing, retain gap with Forming Workpiece, 3-5 tiny oilholes (IV) of longitudinal arrangement are processed to each bottom of the tooth position, in advance Stress mould fixed cover (1) processes oil pocket with respect to oil-hole location, and lubricating oil is by pre-stress die fixed cover (1) oil in process Intracavitary is filled with tiny oilhole (IV), and oil pressure is less than 5MPa, makes extrusion die (2) lubrication more abundant；

Shaped segment (II) is with carrying out laser scored, formation in the middle part of described extrusion die (2) on wedge-shaped changeover portion (III) each inclined-plane Surface Texture is to reduce frictional force.

2. a kind of wedge shape with Surface Texture according to claim 1 becomes the porous lubrication splined shaft extrusion die of modulus, It is characterized in that：Described extrusion die (2) bottom inlet undercut ss keeps one with the Leading end chamfer for processing axis and shaft partses Cause, and at least 30 degree.