Steering engine gear shaft helical tooth extrusion die

Abstract

The utility model discloses a steering gear shaft helical tooth extrusion die which comprises an upper die fixedly connected with a press sliding block, a lower die fastened with a workbench and a large nut installed on the lower die and used for locking and loosening the lower die, the large nut is located on the lower die in the direction close to the upper die, and the upper die and the lower die are coaxially installed. The upper die extrudes towards a forge piece between the upper die and the lower die, the forge piece is extruded in a spiral working belt on the lower die to form a spiral tooth shape, and after the upper die moves downwards to a limited position, the spiral tooth shape on the forge piece is extruded; the upper ejector rod and the lower ejector rod of the workbench move upwards and drive the forge piece to move upwards, the spiral teeth on the forge piece drive the forming female die on the lower die body to rotate reversely, the forge piece is made to be smoothly separated from the lower die body, the die is used for one-time extrusion forming of the spiral teeth, the material utilization rate is increased, and the production efficiency is greatly improved. And the forged helical teeth are high in strength.

Description

Technical Field

[0001] The utility model relates to the field of mechanical manufacturing and processing equipment, in particular to a steering gear gear shaft spiral tooth extrusion die. Background Art

[0002] As a pillar industry, the automobile industry connects the primary, secondary and tertiary industries. It not only directly brings significant economic benefits, but its industrial system and industrial chain penetrate into a wide range of disciplines, driving the rapid development of a large number of related industries, inducing the emergence of emerging industries and high-tech, and forming a huge industrial system and a vertical and horizontal industrial chain. Cars have changed from being out of reach to being common commodities, and travel has become unfettered. People's lifestyles, life concepts and quality of life have changed because of cars. Many people's concept of time is no longer limited to the timetable of public transportation, and the concept of distance is no longer limited to "a few stops". Therefore, cars have become a symbol of freedom, and people buy cars to change their lives.

[0003] Urbanization and the formation of clustered cities are the effects of automobiles. Clustered cities are conducive to the expansion of urban space, which in turn is conducive to the improvement of the automobile use environment, leading to an increase in the speed of automobile circulation and further increase in automobile demand. The income of urban residents has steadily increased, and they have become the main consumers of the automobile market.

[0004] The steering gear is a major component in a car. The energy required for steering a car using a power steering system is, under normal circumstances, only a small part of the energy provided by the driver, and most of it is the hydraulic energy (or air pressure energy) provided by the oil pump (or air compressor) driven by the engine (or motor). For the forgings of the gear shaft of the steering gear of the car, due to the high requirements for the tooth direction accuracy of the helical teeth, machining is often used in the prior art to meet the market requirements. However, the disadvantages of machining helical teeth are: difficult processing, high-precision machining equipment is required, low processing efficiency, low material utilization, and high cost.

[0005] For example, US Pat. No. 5,996,229A discloses a method and a mold for forming a spiral bevel gear from metal powder. The method comprises the following steps: (a) providing a mold having a mold cavity, the mold cavity comprising a middle section corresponding to the profile of a spiral bevel gear, an upper section corresponding to the profile of a first spiral gear, a middle section to form a first joint, and a lower section corresponding to the profile of a second spiral gear and adjacent to the middle section to form a second joint; (b) closing the lower section by tightening the second spiral gear in the lower section; (c) filling the mold cavity with metal powder; (d) closing the cavity by screwing the first spiral gear into the upper section; (e) squeezing the metal powder by continuing the tightening action of the first and second spiral gears until the second spiral gear reaches the second joint and the first spiral gear stops outside the first joint to form a combination of a green shape bevel spiral gear and a residual part; (f) screwing the first spiral gear out of the first section; and (g) gradually tightening the second spiral gear toward the middle part so that the remaining part rotates along the upper part so as to discharge the middle part and the upper part. The technical solution discloses a manufacturing mold and method for spiral bevel gears, but the equipment has high precision requirements and low processing efficiency.

[0006] Another example is a forging die and forging die manufacturing method for extruding external or internal spline helical gears disclosed in US Pat. No. 5,052,210A, in which the front end face of each die tooth includes a compound angle so that the end face will have two end faces. One end face will protrude from the top of the driving side of the die tooth to the other end face protrudes from the protrusion of the die tooth to the coast side. Depending on the situation, each end face protrudes or is formed or defined by an angle A or B, relative to a cross section taken of the die tooth at a plane y parallel to the vertical axis of the die, which is calculated to ensure that the average directional flow of the material will produce a composite vector in a direction parallel to the die to form any angle of the spiral die tooth. The composite angle of the die tooth end face is calculated by geometrically determining the force vector acting on the driving side and sliding side end faces of any pair of adjacent die teeth, and the slopes of these end faces must be calculated by solving two equations simultaneously to ensure that the resultant force vector of the extruded gear blank is oriented substantially parallel to the helix angle of the die. This technical solution discloses a forging die and a method for manufacturing a forging die for a helical gear, but it places extremely high demands on operators, and the processing requirements and processing accuracy are very high. If a small mistake leads to a calculation error, it is very easy to cause the product to be scrapped, with high costs and low material utilization. Utility Model Content

[0007] Purpose of the utility model: The purpose of the utility model is to solve the deficiencies of the prior art and to provide a steering gear gear shaft spiral tooth extrusion die, which is used for one-time extrusion forming of the spiral teeth, which not only improves the material utilization rate, but also greatly improves the production efficiency, and the spiral teeth forged by forging have high strength.

[0008] Technical solution: In order to achieve the above purpose, the utility model discloses a steering gear gear shaft spiral gear extrusion die, which includes an upper die fixedly connected to a press slide, a lower die fastened to a workbench, and a large nut installed on the lower die for locking and loosening the lower die, wherein the large nut is located on the lower die in a direction close to the upper die, and the upper die and the lower die are coaxially installed;

[0009] The upper die is pressed toward the forging located between the upper die and the lower die, and the forging is pressed in the spiral working zone on the lower die to form a spiral tooth shape. After the upper die moves downward to a limited position, the spiral tooth shape on the forging is pressed.

[0010] The upper and lower ejector rods on the workbench move upward and drive the forging to move upward. The spiral teeth on the forging drive the forming die on the lower die to rotate in the opposite direction, allowing the forging to smoothly separate from the lower die.

[0011] As a further preferred embodiment of the present invention, the upper die comprises: a coaxially mounted upper die assembly, an inner punch, an upper die pad A, an upper ejector rod, an upper die cylinder and an upper die pad B;

[0012] One end of the upper mold pad A is fastened to the mold barrel of the lower mold frame, and the other end of the upper mold pad A is fixedly connected to the upper mold barrel through the upper mold pad B. The upper mold assembly provided in the upper mold barrel is close to the mold pad B;

[0013] One end of the upper ejector rod is connected to the press slide, and the other end vertically passes through the lower die frame die cylinder and the upper die pad A and is connected to the inner punch to drive the inner punch to move linearly in the upper die assembly.

[0014] As a further preferred embodiment of the present invention, the end of the inner punch is provided with a tapered surface.

[0015] As a further preferred embodiment of the present invention, the end of the inner punch away from the upper ejector rod has a larger taper.

[0016] As a further preferred embodiment of the present invention, the upper mold cylinder is fastened to the lower mold frame mold cylinder by means of a threaded connection.

[0017] As a further preferred embodiment of the present invention, the lower die comprises a coaxially mounted forming die, a transition ring A, a transition ring B, a cushion block D, a cylindrical roller bearing, a lower ejector rod, a cushion block C, a lower ejector rod cushion block, a thrust spherical roller bearing, a lower ejector rod and a lower die frame mold cylinder;

[0018] One end of the lower ejector rod is vertically fixed and penetrated on the workbench, and the other end of the lower ejector rod is fastened to the lower ejector rod pad installed in the pad C. The lower ejector rod pad is placed on the end surface of the workbench, and the upper part of the pad C is close to the pad D and the forming die in sequence. The radial outer side of the pad D is sleeved with a transition ring B, and the radial outer side of the forming die is sleeved with a transition ring A, and the transition ring A and the transition ring B are radially limited by the lower die frame die cylinder;

[0019] The thrust spherical roller bearing located below the radial step of the pad C is connected with the pad C by interference fit and is flush with the workbench surface. One end of the cylindrical roller bearing located above the radial step of the pad C is connected with the inner surface of the pad C by interference fit, and the other end of the cylindrical roller bearing is in close contact with the transition ring B, so that the cylindrical roller bearing drives the pad C, the pad D and the forming die to rotate in the transition ring B.

[0020] One end of the lower ejector rod is passed through the pad D, and the other end of the lower ejector rod is vertically fixed on the lower ejector rod pad. The lower ejector rod pad is pushed upward by the lower ejector rod to move linearly, and then the lower ejector rod pad drives the lower ejector rod to move linearly and push the forging upward. After the forging receives the axial thrust of the lower ejector rod, the spiral teeth on the forging drive the lower die to rotate in the opposite direction, thereby smoothly separating from the lower die to achieve demolding.

[0021] As a further preferred embodiment of the present invention, the axial top end face of the cushion block C is fixedly connected to the cushion block D by means of a threaded connection, and the axial bottom end face of the cushion block C is 2 mm to 3 mm away from the workbench.

[0022] As a further preferred embodiment of the present invention, a gap is provided between the forming die and the transition ring A, a gap is provided between the cushion block D and the transition ring B, and a gap of 0.2 mm to 0.25 mm is provided between the cylindrical roller bearing and the transition ring B.

[0023] As a further preferred embodiment of the utility model, a plurality of small holes for locking the forming die are evenly arranged on the radial outer side of the large nut, and the rod inserted in the small hole rotates the large nut in clockwise and counterclockwise directions. The large nut is rotated by inserting the rod into the small hole, so that the large nut, the forming die and the transition ring A are axially pressed to achieve the locking of the large nut to the forming die, and the large nut is inserted into the small hole to rotate the large nut in the opposite direction so that there is a gap between the large nut and the transition ring A to achieve the loosening of the forming die.

[0024] As a further preferred embodiment of the utility model, a working belt is provided in the forming die, and a single-sided 0.15 air-permeable gap is provided behind the working belt. The purpose of providing the air-permeable gap is to reduce the forming force, and the forging is extruded into spiral teeth through the working belt of the forming lower die.

[0025] How it works

[0026] When the forging is being extruded, the large nut locks the lower die, and when the forging is not being extruded, the large nut loosens the lower die. Since the forming die will drive the pad D, cylindrical roller bearing and pad C to rotate, when the forging is extruded, in order to ensure the smooth progress of the extrusion process, the circumferential direction of the forming die must not rotate. Therefore, the large nut limits the axial position of the forming die to ensure the smooth extrusion process of the forging. After the extrusion process of the forging is completed, the large nut loosens the forming die, and the forging in the forming die receives the axial thrust of the lower ejector rod. The spiral tooth shape on the forging after extrusion drives the pad D, cylindrical roller bearing and pad C to rotate in the opposite direction, so as to demold smoothly. The demolding process is transformed into the rotary motion of the forming die, pad D, cylindrical roller bearing and pad C by utilizing the linear reciprocating motion of the lower ejector rod.

[0027] Beneficial effects: Compared with the prior art, the steering gear shaft spiral tooth extrusion die of the utility model has the following advantages:

[0028] (1) By adopting a roller bearing combination, it can not only bear the axial load but also enable the forging to rotate upward in the direction of the helix angle during ejection, and the tooth direction accuracy can be controlled within 0.02, thus ensuring that the tooth direction accuracy of the helical teeth is not affected during ejection;

[0029] (2) The upper die assembly and the forming die adopt die guide to ensure the concentricity of the forging after the upper and lower dies are formed;

[0030] (3) The mold structure adopts a three-layer prestressed structure with high mold strength. In addition, the middle ring is made of cemented carbide, which ensures zero ejection after the forging is formed, ensuring the stability of the forging size and greatly improving the mold life;

[0031] (4) The products obtained by using this mold have high precision and low scrap rate, which reduces the overall cost and alleviates the pressure of investment cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a full cross-sectional view of the utility model;

[0033] Figure 2 It is a full cross-sectional view of the forming die;

[0034] Figure 3 This is a top view of the working belt. DETAILED DESCRIPTION

[0035] The utility model will be further explained below in conjunction with the accompanying drawings.

[0036] like Figure 1As shown, the utility model describes a steering gear shaft spiral tooth extrusion die, which includes: an upper die 1, a lower die 2, a press slide 3, a workbench 4, a working belt 5, an upper die assembly 11, an inner punch 12, an upper die pad A13, an upper ejector rod 14, an upper die barrel 15, an upper die pad B16, a forming die 21, a transition ring A22, a transition ring B23, a pad D24, a cylindrical roller bearing 25, a lower ejector rod 26, a pad C27, a lower ejector rod pad 28, a thrust spherical roller bearing 29, a lower ejector rod 20 and a lower die frame die barrel 200.

[0037] Example

[0038] Step 1: After the forging 100 is surface treated, it is placed in the forming die 21, and the large nut 6 is rotated by inserting a rod into the small hole 211, so that the large nut 6, the forming die 21 and the transition ring A22 are axially pressed to achieve the locking of the large nut 6 on the forming die 21;

[0039] Step 2: A working belt 5 is provided in the forming die 21, and a single-side 0.15 permeable gap 51 is provided behind the working belt 5. The press slide 3 drives the inner punch 12 to move downward, and the forging 100 enters the upper die assembly 11. The forging 100 is extruded into a spiral tooth shape in the spiral working belt 5 on the lower die 2. After the upper die 1 moves downward to a limited position, the spiral tooth shape on the forging 100 is extruded. After the PLC circuit receives the signal of the position sensor of the upper die 1 position, the press slide 3 connected to the PLC circuit drives the inner punch 12 to move upward, as shown in FIG. Figure 2 , Figure 3 As shown;

[0040] Step 3: Insert a rod into the small hole 211 and rotate the large nut 6 in reverse to create a gap between the large nut 6 and the transition circle A22 to loosen the large nut 6 from the forming die 221;

[0041] Step 4: The PLC circuit sends a signal to the machine tool ejector rod to push the lower ejector rod 20 to move upward, and the lower ejector rod 20 pushes the lower ejector rod 26 to move upward. When the lower ejector rod 26 contacts the bottom of the forging 100, the forging 100 receives an axial linear thrust, and the spiral tooth shape on the forging 100 causes the forming die 21, the pad D24, the cylindrical roller bearing 25 and the pad C27 to rotate in the opposite direction, so that the forging 100 is demolded in the forming die 21;

[0042] Step 5. After the position sensor located on the forming die 21 sends the signal of forging 100 being taken away to the PLC circuit, the PLC circuit sends a signal to the machine tool push rod, and the machine tool push rod retreats to the lower limit position. The lower ejector rod moves downward due to its own weight. Since the mold teeth are evenly distributed, the forming die does not need to be reset. It only needs to tighten the large nut to start extrusion of the next billet.

[0043] The above implementation is only to illustrate the technical concept and features of the utility model, and its purpose is to enable technicians familiar with the technical field to understand the content of the utility model and implement it accordingly, and it cannot be used to limit the protection scope of the utility model. Any equivalent changes or modifications made according to the spirit of the utility model should be included in the protection scope of the utility model.

Claims

1. A steering gear gear shaft spiral gear extrusion die, characterized in that: It comprises an upper die (1) fixedly connected to a press slide (3), a lower die (2) fastened to a workbench (4), and a large nut (6) mounted on the lower die (2) for locking and loosening the lower die (2), wherein the large nut (6) is located on the lower die (2) in a direction close to the upper die (1), and the upper die (1) and the lower die (2) are coaxially mounted; The upper die (1) is pressed toward the forging (100) located between the upper die (1) and the lower die (2), and the forging (100) is pressed in the spiral working zone (5) on the lower die (2) to form a spiral tooth shape. After the upper die (1) moves downward to a limited position, the spiral tooth shape on the forging (100) is pressed. When the forging (100) is being squeezed, the large nut (6) locks the lower die (2); when the forging (100) is not being squeezed, the large nut (6) loosens the lower die (2); The upper and lower ejector rods (20) of the workbench (4) move upward and drive the forging (100) to move upward, and the spiral teeth on the forging (100) drive the forming die (21) on the lower die (2) to rotate in the opposite direction, so that the forging (100) can be smoothly separated from the lower die (2).

2. The steering gear shaft spiral tooth extrusion die according to claim 1, characterized in that: The upper die (1) comprises: a coaxially mounted upper die assembly (11), an inner punch (12), an upper die pad A (13), an upper ejector rod (14), an upper die cylinder (15) and an upper die pad B (16); One end of the upper die pad A (13) is fastened to the lower die frame die barrel (200), and the other end of the upper die pad A (13) is fixedly connected to the upper die barrel (15) via the upper die pad B (16). The upper die assembly (11) provided in the upper die barrel (15) is in close contact with the die pad B (16). One end of the upper ejector rod (14) is connected to the press slide (3), and the other end vertically passes through the lower die frame die cylinder (200) and the upper die pad A (13) and then is connected to the inner punch (12) to drive the inner punch (12) to move linearly in the upper die assembly (11).

3. The steering gear shaft spiral tooth extrusion die according to claim 2, characterized in that: The end of the inner punch (12) is provided with a conical surface.

4. The steering gear shaft spiral tooth extrusion die according to claim 3, characterized in that: The end of the inner punch (12) away from the upper ejector rod (14) has a greater taper.

5. The steering gear shaft spiral tooth extrusion die according to claim 2, characterized in that: The upper mold cylinder (15) is fastened to the lower mold frame mold cylinder (200) by means of threaded connection.

6. The steering gear shaft spiral tooth extrusion die according to claim 1, characterized in that: The lower die (2) comprises a coaxially mounted forming die (21), a transition ring A (22), a transition ring B (23), a cushion block D (24), a cylindrical roller bearing (25), a lower ejector rod (26), a cushion block C (27), a lower ejector rod cushion block (28), a thrust spherical roller bearing (29), a lower ejector rod (20) and a lower die frame die cylinder (200); One end of the lower ejector rod (20) is vertically fixed and penetrated on the workbench (4), and the other end of the lower ejector rod (20) is fastened to a lower ejector rod pad (28) installed in a pad C (27). The lower ejector rod pad (28) is placed on the upper end surface of the workbench (4), and the upper part of the pad C (27) is close to the pad D (24) and the forming die (21) in sequence. The pad D (24) is radially sleeved with a transition ring B (23), and the radial outer side of the forming die (21) is radially sleeved with a transition ring A (22), and the transition ring A (22) and the transition ring B (23) are radially limited by the lower mold frame mold cylinder (200); A thrust spherical roller bearing (29) provided below the radial step of the pad C (27) is connected to the pad C (27) by interference fit and is flush with the surface of the workbench (4); one end of a cylindrical roller bearing (25) provided above the radial step of the pad C (27) is connected to the inner surface of the pad C (27) by interference fit, and the other end of the cylindrical roller bearing (25) is closely attached to the transition ring B (23), so that the cylindrical roller bearing (25) drives the pad C (27), the pad D (24) and the forming die (21) to rotate in the transition ring B (23). One end of the lower ejector rod (26) is inserted into the cushion block D (24), and the other end of the lower ejector rod (26) is vertically fixed on the lower ejector rod cushion block (28). The lower ejector rod (20) pushes the lower ejector rod cushion block (28) upward to move linearly, and then the lower ejector rod cushion block (28) drives the lower ejector rod (26) to move linearly upward to push the forging (100). After the forging (100) receives the axial thrust of the lower ejector rod (26), the spiral teeth on the forging (100) drive the lower die (2) to rotate in the opposite direction, thereby smoothly separating from the lower die (2) to achieve demoulding.

7. The steering gear shaft spiral tooth extrusion die according to claim 6, characterized in that: The axial top end surface of the cushion block C (27) is fixedly connected to the cushion block D (24) by means of a threaded connection, and the axial bottom end surface of the cushion block C (27) is 2 mm to 3 mm away from the workbench (4).

8. The steering gear shaft spiral tooth extrusion die according to claim 6, characterized in that: A gap is provided between the forming die (21) and the transition ring A (22), a gap is provided between the cushion block D (24) and the transition ring B (23), and a gap of 0.2 mm to 0.25 mm is provided between the cylindrical roller bearing (25) and the transition ring B (23).

9. The steering gear shaft spiral tooth extrusion die according to claim 1, characterized in that: A plurality of small holes (211) for locking the forming die (21) are evenly arranged on the radial outer side of the large nut (6); rods inserted into the small holes (211) rotate the large nut (6) in clockwise and counterclockwise directions.

10. The steering gear shaft spiral tooth extrusion die according to claim 6, characterized in that: A permeable gap (51) is provided on one side of the working belt (5).

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