CN110861699A

CN110861699A - Steering gear and machining method thereof

Info

Publication number: CN110861699A
Application number: CN201911332346.0A
Authority: CN
Inventors: 张敏
Original assignee: Shanghai Car Technology Development Co Ltd
Current assignee: Shanghai Car Technology Development Co Ltd
Priority date: 2019-12-22
Filing date: 2019-12-22
Publication date: 2020-03-06

Abstract

The invention relates to a steering gear, which comprises a steering gear body, wherein the steering gear body is of an integrally formed stepped cylindrical structure and comprises a first section, a second section, a third section and a fourth section which are coaxially connected in sequence, a hollow groove is formed in the axial end face of the first section of the steering gear body, a spline is processed on the surface of the first section through gear rolling, the tail end of the first section is an excircle part, a first annular groove is formed at one end of the spline far away from the excircle part, and a second annular groove is formed in one end, close to the excircle part, of the spline, the bottom diameters of the first annular groove and the second annular groove are 1.2-2mm smaller than the major diameter of the spline, the width of the first annular groove is 1/5-1/4 of the length of the spline, and the width of the second annular groove is 1/3-2/3 of the length of the spline. In the gear rolling processing process, the chamfer width is designed, the chamfer bottom diameter is reduced, the hollow gear rolling deformation is reduced, the metal flowing space is increased, and the axial and radial sizes of the gear rolling processing are ensured.

Description

Steering gear and machining method thereof

Technical Field

The invention relates to the technical field of automobile steering gears, in particular to a steering gear and a machining method thereof.

Background

The steering gear is an important component in an automobile steering system, the gear rack steering gear is a mechanical steering gear which is commonly applied in the automobile steering system, the structural design form of the mechanical steering gear has direct influence on the friction feeling, the center feeling and the aligning performance of the whole automobile steering system, and further has direct influence on the quality feeling and the driving pleasure of the whole automobile.

The gear of the steering gear is one of the components of the steering gear, in the production of the gear of the steering gear, the gear rolling is needed to process the spline, the relative motion of the upper and lower gear rolling plates is involved, the workpiece is driven to rotate and is gradually extruded and formed, the metal material has certain fluidity, the size of the gear of the steering gear is easy to change in the gear rolling processing process, and particularly when the spline is formed, the axial size is influenced, and the product size is easy to be unqualified.

Disclosure of Invention

The invention aims to solve the problems and provide a steering gear and a processing method thereof.

The purpose of the invention is realized by the following technical scheme:

a steering gear comprises a steering gear body which is of an integrally formed stepped cylindrical structure and comprises a first section, a second section, a third section and a fourth section which are coaxially connected in sequence, the steering gear body is provided with a hollow groove on the axial end surface of the first section, the surface of the first section is processed into a spline by gear rolling, the tail end of the first section is an excircle part, one end of the spline far away from the excircle part is provided with a first annular groove, a second annular groove is formed in one end, close to the excircle part, of the spline, the bottom diameters of the first annular groove and the second annular groove are 1.2-2mm smaller than the major diameter of the spline, the width of the first annular groove is 1/5-1/4 of the spline length, the width of the second annular groove is 1/3-2/3 of the spline length. The size is defined according to the deformation of the hollow gear and the space for the metal to flow; the oversize causes the axial dimension to be out of tolerance, thus affecting the assembly, or the integral axial dimension of the spline does not meet the initial axial length; and when the size is too small, no flowing space exists in metal flowing caused by the gear rolling, deformation is caused, the size of the spline is unqualified, and the like.

According to the invention, the first annular groove and the second annular groove with preset sizes are arranged on the two sides of the spline, so that the metal flowing space can be increased in the previous process of the gear rolling, the deformation of the gear rolling is greatly reduced, the influence of the processing on the adjacent excircle is avoided, and the forming and size accuracy of the spline is fully ensured.

Further, the first annular groove with the junction of spline sets up the chamfer, keeps away from the one end of spline sets up the radius.

Further, the chamfer that first annular groove with the junction setting of spline is 30, and the radius that keeps away from the one end setting of spline is 0.5 mm. The arc angles at the two ends of the spline are the same as the bottom diameter, so that the gear rolling processing is facilitated; the chamfer is set differently according to the different external diameters of connected excircles, thereby achieving the purposes of being convenient for processing and reducing deformation.

Further, the second annular groove with the junction of spline sets up the chamfer, keeps away from the one end of spline sets up the radius.

Further, the chamfer that the second annular groove set up with the junction of spline is 15, and the radius that keeps away from the one end setting of spline is 0.5 mm. The arc angles at the two ends of the spline are the same as the bottom diameter, so that the gear rolling processing is facilitated; the chamfer is set differently according to the different external diameters of connected excircles, thereby achieving the purposes of being convenient for processing and reducing deformation.

Furthermore, the diameters of the gear body of the steering gear are reduced along the first section, the second section, the third section and the fourth section in sequence.

Further, the total length of the steering gear is 120-130mm, and the diameter of the hollow groove is 15-17 mm.

Furthermore, the length of the spline is 8-9mm, the modulus is 0.3, the pressure angle is 30 degrees, the number of teeth is 115-120, the major diameter is 35.1-35.2mm, and the minor diameter is 34.3-34.4 mm.

Furthermore, the steering gear body is provided with a flange at the outer side of the first section, two ends of the second section are provided with grooves, and the joint of the fourth section and the third section is provided with a groove.

A method for processing a steering gear comprises the steps of processing a first annular groove and a second annular groove with preset sizes on a first section of the steering gear, and then processing a spline through gear rolling.

The gear rolling processing is to process a shaft gear, a hollow hole on the end surface and gear rolling on the excircle. The gear rolling processing is that two gear rolling plates which are arranged on a sliding table in an up-down opposite mode are driven to move relatively linearly by oil pressure or a servo motor after being synchronized by a synchronous gear, the gear rolling plates are ground into a tooth shape which is gradually cut in, a workpiece is supported by front and rear centers and can conveniently adjust the processing position of the workpiece through the movement of the front and rear centers, the workpiece is driven to rotate by the relative movement of the upper and lower gear rolling plates and is gradually extruded and formed, and the workpiece finally exits after being shaped.

The spline cold forming is actually a chipless processing process in which tooth root materials are gradually extruded and replaced to tooth tops once, chipless forming is completed within a few seconds, and the spline cold forming method is a high-relative-precision and economical processing method for the excircle spline.

Compared with the prior art, the invention has the following advantages:

the invention reasonably determines the size of the annular grooves at two sides of the spline so as to meet the processing requirement of the spline and fully ensure the forming size of the spline, and in the gear rolling processing process, the chamfer width is designed, so that the chamfer bottom diameter is reduced, the hollow gear rolling deformation is reduced, the metal flowing space is increased, and the axial and radial sizes of the gear rolling processing are ensured.

Drawings

FIG. 1 is a schematic view of the construction of a steering gear according to the present invention;

FIG. 2 and FIG. 3 are schematic structural diagrams of an embodiment of the present invention;

FIG. 4 is an enlarged view of a portion at X in FIGS. 2 and 3;

in the figure: first section 100, second section 200, third section 300, fourth section 400, flange 500, hollow groove 600, spline 101, second annular groove 102, first annular groove 103, outer cylindrical portion 104.

Detailed Description

The invention is described in detail below with reference to the figures and specific embodiments.

Examples

As shown in fig. 1, a steering gear comprises a steering gear body, wherein the steering gear body is of an integrally formed stepped cylindrical structure and comprises a first section 100, a second section 200, a third section 300 and a fourth section 400 which are coaxially connected in sequence, the diameters of the steering gear body along the first section 100, the second section 200, the third section 300 and the fourth section 400 are sequentially reduced, a flange 500 is arranged on the outer side of the first section 100 of the steering gear body, grooves are arranged at two ends of the second section 200, a groove is arranged at the joint of the fourth section 400 and the third section 300, and a hollow groove 600 is formed in the axial end face of the first section 100 of the steering gear body.

A spline 101 is machined on the surface of the first section 100 through gear rolling, an excircle part 104 is arranged at the tail end of the first section 100, a first annular groove 103 is formed in one end, far away from the excircle part 104, of the spline 101, a second annular groove 102 is formed in one end, close to the excircle part 104, of the spline 101, the bottom diameters of the first annular groove 103 and the second annular groove are 1.2-2mm smaller than the major diameter of the spline 101, the width of the first annular groove 103 is 1/5-1/4 of the length of the spline 101, and the width of the second annular groove 102 is 1/3-2/3 of the length of the spline 101.

In this embodiment, the total length of the steering gear is 122mm and the diameter of the hollow groove 600 is 16mm, as shown in fig. 2, 3 and 4. The spline 101 has a length of 8.7mm, a modulus of 0.3, a pressure angle of 30 °, a number of teeth of 116, a major diameter of 35.16mm, and a minor diameter of 34.32 mm. The junction of the first annular groove 103 and the spline 101 is chamfered, and one end away from the spline 101 is rounded. The chamfer angle at the junction of the first annular groove 103 and the spline 101 is 30 ° and the radius at the end remote from the spline 101 is 0.5 mm. The junction of the second annular groove 102 and the spline 101 is chamfered and the end remote from the spline 101 is rounded. The junction of the second annular groove 102 and the spline 101 is chamfered at 15 ° and the end remote from the spline 101 is rounded with a radius of 0.5 mm.

During specific machining, a first annular groove 103 and a second annular groove 102 with preset sizes are machined in a first section 100 of the steering gear, and then the spline 101 is machined through gear rolling. The gear rolling processing is to process a shaft gear, a hollow hole on the end surface and gear rolling on the excircle. The gear rolling processing is that two gear rolling plates which are arranged on a sliding table in an up-down opposite mode are driven to move relatively linearly by oil pressure or a servo motor after being synchronized by a synchronous gear, the gear rolling plates are ground into a tooth shape which is gradually cut in, a workpiece is supported by front and rear centers and can conveniently adjust the processing position of the workpiece through the movement of the front and rear centers, the workpiece is driven to rotate by the relative movement of the upper and lower gear rolling plates and is gradually extruded and formed, and the workpiece finally exits after being shaped.

The embodiments described above are described to facilitate an understanding and use of the invention by those skilled in the art. It will be readily apparent to those skilled in the art that various modifications to these embodiments may be made, and the generic principles described herein may be applied to other embodiments without the use of the inventive faculty. Therefore, the present invention is not limited to the above embodiments, and those skilled in the art should make improvements and modifications within the scope of the present invention based on the disclosure of the present invention.

Claims

1. A steering gear comprises a steering gear body which is of an integrally formed stepped cylindrical structure and comprises a first section (100), a second section (200), a third section (300) and a fourth section (400) which are coaxially connected in sequence, wherein a hollow groove (600) is formed in the axial end face of the first section (100) of the steering gear body, a spline (101) is machined on the surface of the first section (100) through gear rolling, an outer circle part (104) is arranged at the tail end of the first section (100),

the spline is characterized in that one end of the spline (101) far away from the excircle part (104) is provided with a first annular groove (103), one end of the spline (101) near the excircle part (104) is provided with a second annular groove (102), the bottom diameters of the first annular groove (103) and the second annular groove are 1.2-2mm smaller than the major diameter of the spline (101), the width of the first annular groove (103) is 1/5-1/4 of the length of the spline (101), and the width of the second annular groove (102) is 1/3-2/3 of the length of the spline (101).

2. A diverter gear according to claim 1, characterized in that the junction of the first annular groove (103) with the spline (101) is chamfered and the end remote from the spline (101) is rounded.

3. A diverter gear according to claim 2, characterized in that the junction of the first annular groove (103) with the spline (101) is chamfered by 30 ° and the end remote from the spline (101) is rounded by 0.5 mm.

4. A diverter gear according to claim 1, characterized in that the junction of the second annular groove (102) with the spline (101) is chamfered and that the end remote from the spline (101) is rounded.

5. A diverter gear according to claim 4, characterized in that the junction of the second annular groove (102) with the spline (101) is chamfered with 15 ° and the end remote from the spline (101) is rounded with a radius of 0.5 mm.

6. A diverter gear according to claim 1, wherein the diverter gear body decreases in diameter along the first (100), second (200), third (300) and fourth (400) sections in sequence.

7. A diverter gear according to claim 6, characterized in that the total length of the diverter gear is 120-130mm and the diameter of the hollow groove (600) is 15-17 mm.

8. A diverter gear according to claim 7, characterized in that the splines (101) have a length of 8-9mm, a module of 0.3, a pressure angle of 30 °, a number of teeth of 115 and 120, a major diameter of 35.1-35.2mm and a minor diameter of 34.3-34.4 mm.

9. The steering gear according to claim 1, characterized in that the steering gear body is provided with a flange (500) at the outer side of the first section (100), grooves are provided at both ends of the second section (200), and a groove is provided at the junction of the fourth section (400) and the third section (300).

10. A method of machining a steering gear according to claim 1, wherein the first annular groove (103) and the second annular groove (102) are machined to a predetermined size on the first section (100) of the steering gear, and then the splines (101) are machined by gear rolling.