CN217873854U

CN217873854U - Tooth structure of eighteen-tooth automobile steering intermediate shaft

Info

Publication number: CN217873854U
Application number: CN202222431077.7U
Authority: CN
Inventors: 刘璋; 张斐; 杨龙; 杜轩; 姜殿鑫; 艾涛
Original assignee: Wuhan Jielong Electric Power Steering Co Ltd
Current assignee: Wuhan Jielong Electric Power Steering Co Ltd
Priority date: 2022-09-14
Filing date: 2022-09-14
Publication date: 2022-11-22
Anticipated expiration: 2032-09-14

Abstract

The utility model relates to an eighteen tooth auto steering jackshafts's profile of tooth structure belongs to auto steering part technical field. Including integral key shaft and spline pipe, integral key shaft one end is provided with the external splines tooth, and spline pipe one end is provided with the internal spline groove, and the external splines tooth is the sectional type setting, is provided with between the external splines tooth of each section and cuts apart concavely, and the coating of moulding plastics on the external splines tooth surface has the nylon layer, and external splines tooth top chamfer radius is 0.15 mm, and external splines tooth root chamfer radius is 0.45 mm. The tooth-shaped structure passes through a tooth groove angle of 53.5 degrees, a tooth top chamfer radius of 0.15 mm and a tooth root chamfer radius of an external spline of 0.45 mm; the contact point between the outer spline tooth and the inner spline groove is moved downwards compared with the traditional contact point, so that the transmission stress is more dispersed, and the stress of a single tooth is more uniform; the problem that the nylon layer cannot meet the requirement of 70-90 Nm large torque transmission due to uneven stress caused by the tooth form in the prior art is solved, and the method has positive significance for enterprise development.

Description

Tooth-shaped structure of eighteen-tooth automobile steering intermediate shaft

Technical Field

The utility model relates to an eighteen tooth auto steering jackshafts's profile of tooth structure belongs to auto steering part technical field.

Background

The automobile steering intermediate shaft is an important part of an automobile steering system, and comprises a spline shaft, a spline pipe and a universal joint welded on the spline shaft and the spline pipe. The intermediate shaft is used for connecting the output end of the steering column with the input end of the steering gear to realize torque transmission. Simultaneously, require between integral key shaft and the spline pipe to have the characteristics of mutual slip to satisfy the error that whole car was equipped and steering column angle regulation's demand, and can take place to slide relatively (routed to contract) between integral key shaft and the spline pipe when the automobile body bumps, absorb with the impact conversion, thereby protect the driver to avoid receiving the injury. Because the intermediate shaft is a nested structure of the spline shaft and the spline tube, abrasion inevitably occurs between the tooth grooves of the spline shaft and the teeth of the spline tube along with long-time torque transmission, and once abrasion occurs, the steering performance is directly reduced, and meanwhile, noise is generated. At present, the solution to this problem is to add balls (steel balls) between the spline shaft and the spline tube of the 10-tooth intermediate shaft or 12-tooth intermediate shaft, and to set a nylon layer (sleeve) between the teeth and grooves of the spline shaft and the spline tube, so as to reduce friction force and further reduce abrasion between the spline shaft and the spline tube on the premise of not affecting torsional rigidity. However, the intermediate shaft with the structure has the defects of high manufacturing cost and high assembly precision requirement, and meanwhile, the stress is uneven due to the tooth shapes of the spline shaft and the spline pipe, and a nylon layer cannot meet the large torque transmission requirement of 70-90 Nm; the nylon layer is easy to be squashed, so that the service life is reduced; therefore, on the premise that the nylon layer can meet the requirements of large torque transmission of 70-90 Nm and reduce friction force and abrasion on the basis of the existing intermediate shaft, the improvement on the nylon layer is needed.

Disclosure of Invention

The utility model aims to provide a: the tooth-shaped structure of the eighteen-tooth automobile steering intermediate shaft has the advantages of small torsional gap, high rigidity, small sliding friction, good fatigue durability, uniform stress between the spline shaft and the spline pipe and capability of meeting 70-90 Nm large torque transmission of a nylon layer.

The technical scheme of the utility model is that:

a tooth-shaped structure of an eighteen-tooth automobile steering intermediate shaft comprises a spline shaft and a spline pipe; universal joints are respectively welded at the end heads of one ends of the spline shaft and the spline pipe; the circumference of the end head at the other end of the spline shaft is provided with external spline teeth, the circumference of the inner wall of the end head at the other end of the spline tube is provided with an internal spline groove, and the spline shaft and the spline tube are in sliding connection through the matching of the external spline teeth and the internal spline groove; the end of the spline pipe is provided with a sealing mechanism; the method is characterized in that: the external spline tooth be the sectional type setting, be provided with between the external spline tooth of each section and cut apart concavely, the coating of moulding plastics on external spline tooth surface has the nylon layer, external spline tooth crest chamfer radius be 0.15 mm, external spline tooth root chamfer radius is 0.45 mm.

The outer major diameter of the spline shaft is 22.2mm, the outer minor diameter of the spline shaft is 20.1mm, the inner major diameter of the spline tube is 22.8mm, the inner minor diameter of the spline tube is 20.7mm, and the tooth groove angle of the spline tube is 53.5 degrees.

The groove bottom width of the inner spline groove of the spline pipe is 1.379mm, and the groove top is 1.153mm.

And two ends of each section of external spline tooth of the spline shaft are respectively arranged in a chamfer angle of 60 degrees.

The nylon layer is made of polyformaldehyde resin or PA11; the thickness of the nylon layer was 0.4mm.

The beneficial effects of the utility model reside in that:

the tooth-shaped structure of the eighteen-tooth automobile steering intermediate shaft has the characteristics of small torsional gap, high rigidity, small sliding friction and good fatigue durability, and passes through a tooth groove angle of 53.5 degrees, a tooth crest chamfer radius of 0.15 mm and an external spline tooth root chamfer radius of 0.45 mm; the contact point between the outer spline tooth and the inner spline groove is moved downwards compared with the traditional contact point and is diffused by the contact point, so that the transmission stress (shearing force) is more dispersed, and the stress of a single tooth is more uniform; the nylon layer can meet 70-90 Nm large torque transmission; solves the problems that the existing nylon layer cannot meet the large torque transmission requirement of 70-90 Nm due to uneven stress caused by the tooth shape; and the nylon layer is easily crushed, so that the service life is shortened, and meanwhile, the arrangement of balls (steel balls) is reduced on the basis of the traditional 10-tooth intermediate shaft or 12-tooth intermediate shaft by the tooth-shaped structure, so that the production cost and the assembly precision are reduced, and the tooth-shaped structure has positive significance for enterprise development.

Drawings

Figure 1 is a schematic structural diagram of the present invention,

figure 2 is a schematic sectional structure view of the present invention,

FIG. 3 isbase:Sub>A schematic sectional view taken along line A-A in FIG. 2,

FIG. 4 is a schematic structural view of the spline shaft of the present invention,

figure 5 isbase:Sub>A schematic cross-sectional view taken along linebase:Sub>A-base:Sub>A of figure 4,

fig. 6 is a schematic view of the external spline tooth contact of the present invention.

In the figure: 1. spline shaft, 2, spline pipe, 3, universal joint, 4, external spline tooth, 5, internal spline groove, 6, sealing mechanism, 7, cut apart concave, 8, nylon layer, 9, contact point.

Detailed Description

The tooth-shaped structure of the eighteen-tooth automobile steering intermediate shaft comprises a spline shaft 1 and a spline pipe 2; and universal joints 3 are respectively welded at the end heads of one ends of the spline shaft 1 and the spline pipe 2. The circumference of the end head at the other end of the spline shaft 1 is provided with external spline teeth 4, the circumference of the inner wall of the end head at the other end of the spline tube 2 is provided with an internal spline groove 5, and the spline shaft 1 and the spline tube 2 are in sliding connection through the matching of the external spline teeth 4 and the internal spline groove 5; the end of the spline pipe 2 is provided with a sealing mechanism 6 to form a seal, so that dust is prevented from entering and affecting the sliding performance. The external spline tooth 4 of integral key shaft 1 is the multistage formula setting, is provided with between the external spline tooth 4 of each section and cuts apart concave 7, and the coating of moulding plastics on the external spline tooth 4 surface has nylon layer 8. The nylon layer 8 is made of polyformaldehyde resin or PA11 material; the nylon layer 8 has a thickness of 0.4mm. The effect of cutting apart concave 7 is to divide into the multistage with external spline tooth 4 to guarantee the adnexed fastness on nylon layer 8, avoid appearing axial displacement under the exogenic action between nylon layer 8 and the external spline tooth 4.

The external major diameter of the spline shaft 1 is 22.2mm, the external minor diameter is 20.1mm, the tooth top chamfer radius of the external spline tooth 1 is 0.15 mm, and the tooth root chamfer radius of the external spline tooth 1 is 0.45 mm.

The inner major diameter of the spline tube 2 is 22.8mm, the inner minor diameter is 20.7mm, the tooth space angle of the spline tube 2 is 53.5 degrees, the width of the groove bottom of the inner spline groove 5 of the spline tube 2 is 1.379mm, and the groove top is 1.153mm.

In the tooth profile structure, the radius of the chamfer of the tooth top of the external spline tooth 1 is 0.15 mm, and the radius of the chamfer of the tooth root of the external spline tooth 1 is 0.45 mm; the tooth groove angle of the spline tube 2 is 53.5 degrees; in the torque transmission process of the spline shaft 1 and the spline pipe 2, compared with the situation that the contact point 9 between the external spline tooth 1 and the internal spline groove 5 of the existing intermediate shaft moves downwards (the radius of the tooth top chamfer angle) below the contact point 9 between the external spline tooth 1 and the internal spline groove 5, the transmission stress is diffused outwards through the contact point 9 and is excessive through the radius of the tooth top chamfer angle of 0.15 mm, so that the stress of a single tooth is more uniform; the crushing condition caused by stress concentration of the existing nylon layer 8 is effectively avoided, so that the nylon layer 8 can meet the large torque transmission requirement of 70-90 Nm; solves the problem that the nylon layer 8 can not meet the large torque transmission requirement of 70-90 Nm due to uneven stress caused by the tooth form in the prior art; and the nylon layer is easily crushed, so that the service life is reduced, and meanwhile, the arrangement of balls (steel balls) is reduced on the basis of the traditional 10-tooth intermediate shaft or 12-tooth intermediate shaft by the tooth-shaped structure, so that the production cost and the assembly precision are reduced.

In order to verify the properties of the tooth-shaped structure, the applicant carried out finite element analysis on the strength of a single tooth of the spline shaft 1 coated with different nylon materials, and the results are as follows:

。

Claims

1. a tooth-shaped structure of an eighteen-tooth automobile steering intermediate shaft comprises a spline shaft (1) and a spline pipe (2); universal joints (3) are respectively welded at the end heads of one ends of the spline shaft (1) and the spline pipe (2); the circumference of the end head at the other end of the spline shaft (1) is provided with external spline teeth (4), the circumference of the inner wall of the end head at the other end of the spline pipe (2) is provided with an internal spline groove (5), and the spline shaft (1) and the spline pipe (2) are in sliding connection through the matching of the external spline teeth (4) and the internal spline groove (5); the end of the spline tube (2) is provided with a sealing mechanism (6); the method is characterized in that: the outer spline tooth (4) be the sectional type setting, be provided with between the outer spline tooth (4) of each section and cut apart concave (7), the coating of moulding plastics on outer spline tooth (4) surface has nylon layer (8), outer spline tooth (4) tooth top chamfer radius be 0.15 mm, outer spline tooth (4) tooth root chamfer radius is 0.45 mm.

2. The tooth profile structure of an eighteen-tooth automobile steering intermediate shaft according to claim 1, characterized in that: the outer major diameter of the spline shaft (1) is 22.2mm, the outer minor diameter of the spline shaft is 20.1mm, the inner major diameter of the spline tube (2) is 22.8mm, the inner minor diameter of the spline tube is 20.7mm, and the tooth groove angle of the spline tube (2) is 53.5 degrees.

3. The tooth profile structure of an eighteen-tooth automobile steering intermediate shaft according to claim 1, characterized in that: the width of the groove bottom of the inner spline groove (5) of the spline pipe (2) is 1.379mm, and the width of the groove top is 1.153mm.

4. The tooth profile structure of an eighteen-tooth automobile steering intermediate shaft according to claim 1, characterized in that: the two ends of each section of external spline teeth (4) of the spline shaft (1) are respectively arranged in a chamfer angle of 60 degrees.

5. The tooth profile structure of an eighteen-tooth automobile steering intermediate shaft according to claim 1, characterized in that: the nylon layer (8) is made of polyformaldehyde resin or PA11; the thickness of the nylon layer (8) is 0.4mm.