A steering column having a high natural frequency

Abstract

The utility model discloses a steering column with high inherent frequency, including the inner pipe column cylinder of the outer pipe column cylinder sleeve set, and the outside end of inner pipe column cylinder is penetrated to the outside of outer pipe column cylinder and is equipped with the shell, is rotated and is equipped with the input shaft through the bearing no.1 in the outer pipe column cylinder, and the input shaft extends to the inner pipe column cylinder, and the inner pipe column cylinder is equipped with the coupling shaft, and one end of coupling shaft is penetrated to the input shaft, and the input shaft is connected with the coupling shaft through the spline drive, and the flexible bearing support unit is equipped with between the spline cooperation place and the inner pipe column cylinder on the circumference outer wall of input shaft, the other end fixedly equipped with the torsion bar of coupling shaft, the output shaft is rotatably connected with through the bearing no.2 in the shell, and the torsion bar is penetrated to the output shaft, and the torsion bar and output shaft are connected through the spline drive, the coaxial arrangement of input shaft, coupling shaft, torsion bar and output shaft, the utility model has the advantages of high stiffness of mandrel and steering column, the inherent frequency of steering column is high, does not influence the collapse performance of steering column, improves the whole car NVH performance etc.

Description

Technical Field

[0001] This utility model relates to the field of steering column technology, specifically a steering column with a high natural frequency. Background Technology

[0002] In steering systems, customers have increasingly higher requirements for NVH, and the natural frequency of the column body will directly or indirectly affect the NVH performance of the whole vehicle. Traditional structural design, whether it is the thickness of the bracket plate or the design of other reinforcing ribs, cannot effectively improve the natural frequency of the column, and also increases the weight of the column body. From an economic point of view, it has not achieved a balance. Existing automotive electric steering columns, such as the steering column assembly and vehicle disclosed in patent publication number CN106184353B, include an outer column cylinder and an inner column cylinder containing an input shaft, an intermediate shaft, a torsion bar, and an output shaft. The input shaft, intermediate shaft, torsion bar, and output shaft form a spindle. However, the input shaft is only rotatably connected to the outer opening of the outer column cylinder via a single bearing. This results in problems such as low stiffness and low natural frequency of the steering column, which affect the NVH performance of the entire vehicle. Utility Model Content

[0003] The technical problem to be solved by this utility model is to overcome the existing defects and provide a steering column with a high natural frequency. The spindle and steering column have high rigidity, and the steering column has a high natural frequency, which can meet the adjustment of crumple zone requirements without affecting the crumple zone performance of the steering column. This reduces manufacturing costs and installation accuracy, improves assembly efficiency, and improves the NVH performance of the whole vehicle, effectively solving the problems in the background art.

[0004] To achieve the above objectives, this utility model provides the following technical solution: a steering column with a high natural frequency, comprising an outer column, an inner column, and a housing. The inner column is fitted inside the outer column, and one end of the inner column extends through the outer column and is fixedly connected to the housing for mounting transmission components. A tubular input shaft is rotatably mounted inside the outer column via a bearing, extending into the inner column. A connecting shaft is mounted inside the inner column, with one end extending into the input shaft. An internal spline is formed on the inner circumferential wall of the input shaft, and the connecting shaft and the input shaft are connected via spline transmission. A flexible bearing support unit is provided on the outer circumferential wall of the input shaft between the internal spline and the inner column. A torsion bar is fixedly mounted on the other end of the connecting shaft. A tubular output shaft is rotatably connected inside the housing via a bearing, with the torsion bar extending into the output shaft. The torsion bar and the output shaft are connected via spline transmission. The input shaft, connecting shaft, torsion bar, and output shaft are coaxially arranged.

[0005] Furthermore, the flexible bearing support unit is located at the middle position of the inner spline of the input shaft.

[0006] Furthermore, the flexible bearing support unit includes an auxiliary support bearing fixedly mounted on the input shaft. A copper sleeve is fitted on the outer ring of the auxiliary support bearing. Elastic rings are fixed on the outer circumferential walls at both ends of the copper sleeve in the axial direction. The elastic rings are interference-fitted with the inner tube column.

[0007] Furthermore, annular grooves are provided on the outer circumference of the copper sleeve at the positions corresponding to the elastic rings, and the elastic rings are engaged in the annular grooves; elastic feet are uniformly provided on the outer circumference of the outer end face of the elastic rings, and a limiting ring groove is provided on the inner circumference of the inner tube column at the position corresponding to the copper sleeve. The length of the limiting ring groove is adapted to the length between the two elastic rings, and the elastic feet of the elastic rings abut against the axial end of the limiting ring groove.

[0008] Furthermore, a bearing three is provided between the output shaft and the housing, with bearing two and bearing three distributed on both sides of the output shaft.

[0009] Compared with the prior art, the beneficial effects of this utility model are as follows: This steering column with a high natural frequency effectively supports the input shaft through a flexible bearing support unit between the input shaft and the inner column cylinder, preventing the input shaft from having a cantilever beam structure, improving the rigidity of the spindle and steering column. The high natural frequency of the steering column improves the NVH performance of the entire vehicle. Moreover, the flexible bearing support unit is located at the middle position of the inner spline of the input shaft, which can meet the adjustment of the collapsibility requirement. The flexible connection between the copper sleeve and the inner column cylinder is achieved through the elastic ring, reducing manufacturing costs and installation accuracy, improving assembly efficiency, and when the steering column collapses, the auxiliary support bearing slides axially relative to the copper sleeve, quickly disengaging from the copper sleeve without affecting the collapsibility performance of the steering column. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 This is a schematic diagram of the flexible bearing support unit structure of this utility model; Figure 3 This is a schematic diagram of the elastic ring structure of this utility model.

[0011] In the diagram: 1. Outer tube column; 2. Inner tube column; 21. Limiting ring groove; 3. Outer shell; 4. Input shaft; 41. Internal spline; 5. Connecting shaft; 6. Torsion bar; 7. Output shaft; 8. Flexible bearing support unit; 81. Auxiliary support bearing; 82. Copper sleeve; 83. Elastic ring; 831. Elastic foot; 9. Bearing 1; 10. Bearing 2; 11. Bearing 3. Detailed Implementation

[0012] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model. Example

[0013] Please see Figure 1 This utility model provides a technical solution: a steering column with a high natural frequency, comprising an outer column cylinder 1, an inner column cylinder 2, and a housing 3. The inner column cylinder 2 is sleeved inside the outer column cylinder 1, and one end of the inner column cylinder 2 extends through the outer column cylinder 1 and is fixedly connected to the housing 3 for mounting a transmission component. In this embodiment, the transmission component is a worm gear transmission mechanism in an automotive electric power steering column. A tubular input shaft 4 is rotatably mounted inside the outer column cylinder 1 via a bearing 9. In this embodiment, the bearing 9 is located at the outer opening of the outer column cylinder 1, and one end of the input shaft 4... The input shaft 4 extends into the inner tube column 2, and the other end of the input shaft 4 passes through the outer tube column 1. The inner tube column 2 is provided with a connecting shaft 5, one end of which passes through the input shaft 4. An inner spline 41 is provided on the inner circumferential inner wall of the inner end of the input shaft 4. An outer spline 41 that mates with the inner spline 41 is provided on the connecting shaft 5. The connecting shaft 5 and the input shaft 4 are connected by a spline drive. A flexible bearing support unit 8 is provided on the outer circumferential outer wall of the input shaft 4 between the inner spline 41 and the inner tube column 2. The flexible bearing support unit 8 is located at the middle position of the inner spline 41 of the input shaft 4. A torsion bar 6 is fixedly provided at the other end of the connecting shaft 5; a tubular output shaft 7 is rotatably connected inside the housing 3 via bearings 10 and 11. Bearings 10 and 11 are distributed on both sides of the output shaft 7. The torsion bar 6 passes through the output shaft 7. An external spline 2 is provided on the outer wall of the torsion bar 6. An internal spline 2 that mates with the external spline 2 is provided on the inner circumference of the output shaft 7. The torsion bar 6 and the output shaft 7 are connected by spline transmission. The input shaft 4, connecting shaft 5, torsion bar 6 and output shaft 7 are coaxially arranged to form the spindle of the steering column. The flexible bearing support unit 8 provided between the input shaft 4 and the inner column cylinder 2 effectively supports the input shaft 4, prevents the input shaft 4 from having a cantilever beam structure, improves the rigidity of the spindle and the steering column, thereby improving the natural frequency of the steering column and improving the NVH performance of the whole vehicle. The flexible bearing support unit 8 is located at the middle position of the internal spline 41 of the input shaft 4, which can meet the adjustment of the crumple zone.

[0014] Please refer to the following: Figure 2-3The flexible bearing support unit 8 includes an auxiliary support bearing 81 fixedly mounted on the input shaft 4. A copper sleeve 82 is fitted on the outer ring of the auxiliary support bearing 81. Elastic rings 83 are fixed on the outer circumferential walls at both ends of the copper sleeve 82. The elastic rings 83 are interference-fitted with the inner tube column 2. In this embodiment, the axial length of the copper sleeve 82 is greater than the axial length of the auxiliary support bearing 81. The flexible connection between the copper sleeve 82 and the inner tube column 2 is achieved through the elastic rings 83, that is, the flexible connection between the auxiliary support bearing 81 and the inner tube column 2 is achieved, avoiding the rigid connection between the auxiliary support bearing 81 and the inner tube column 2, reducing manufacturing costs and installation accuracy, improving assembly efficiency, and when the steering column collapses, the auxiliary support bearing 81 slides axially relative to the copper sleeve 82, quickly disengaging from the copper sleeve 82 without affecting the collapse performance of the steering column.

[0015] Annular grooves are formed on the outer circumference of the copper sleeve 82 at the positions corresponding to the elastic rings 83, and the elastic rings 83 are engaged in the annular grooves. Elastic feet 831 are evenly provided on the outer circumference of the outer end face of the elastic rings 83. A limiting ring groove 21 is formed on the inner circumference of the inner tube column 2 at the positions corresponding to the copper sleeve 82. The length of the limiting ring groove 21 is adapted to the length between the two elastic rings 83, and the elastic feet 831 of the elastic rings 83 abut against the axial end of the limiting ring groove 21. The elastic support effect of the elastic rings 83 is good, and the copper sleeve 82 and the elastic rings 83 are positioned by the limiting ring groove 21.

[0016] The steering column disclosed in this embodiment has a high natural frequency. The flexible bearing support unit 8 between the input shaft 4 and the inner column cylinder 2 effectively supports the input shaft 4, prevents the input shaft 4 from forming a cantilever beam structure, and improves the rigidity of the spindle and steering column. The steering column has a high natural frequency, and the flexible bearing support unit 8 is located at the middle position of the inner spline 41 of the input shaft 4, which can meet the adjustment of the collapse requirement. The flexible connection between the copper sleeve 82 and the inner column cylinder 2 is achieved by the elastic ring 83, which reduces manufacturing costs and installation accuracy, improves assembly efficiency, and when the steering column collapses, the auxiliary support bearing 81 slides axially relative to the copper sleeve 82, quickly disengaging from the copper sleeve 82 without affecting the collapse performance of the steering column.

[0017] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A steering column with a high natural frequency, comprising an outer column tube, an inner column tube, and a housing, characterized in that: An inner tube is fitted inside the outer tube. One end of the inner tube extends through the outer tube and is fixedly connected to a housing for mounting transmission components. A tubular input shaft is rotatably mounted inside the outer tube via a bearing. The input shaft extends into the inner tube. A connecting shaft is located inside the inner tube. One end of the connecting shaft extends into the input shaft. An internal spline is formed on the inner circumferential wall of the input shaft. The connecting shaft and the input shaft are connected via a spline drive. A flexible bearing support unit is located on the outer circumferential wall of the input shaft between the internal spline and the inner tube. A torsion bar is fixedly mounted on the other end of the connecting shaft. A tubular output shaft is rotatably connected inside the housing via a bearing. A torsion bar extends into the output shaft. The torsion bar and the output shaft are connected via a spline drive. The input shaft, connecting shaft, torsion bar, and output shaft are coaxially arranged.

2. A steering column with a high natural frequency according to claim 1, characterized in that: The flexible bearing support unit is located at the middle position of the inner spline of the input shaft.

3. A steering column with a high natural frequency according to claim 1, characterized in that: The flexible bearing support unit includes an auxiliary support bearing fixedly mounted on the input shaft. A copper sleeve is fitted on the outer ring of the auxiliary support bearing. Elastic rings are fixed on the outer circumferential walls at both ends of the copper sleeve in the axial direction. The elastic rings are interference-fitted with the inner tube column.

4. A steering column with a high natural frequency according to claim 3, characterized in that: Annular grooves are provided on the outer circumference of the copper sleeve at the positions corresponding to the elastic rings, and the elastic rings are engaged in the annular grooves. Elastic feet are uniformly provided on the outer circumference of the outer end face of the elastic rings. Limiting ring grooves are provided on the inner circumference of the inner tube column at the positions corresponding to the copper sleeves. The length of the limiting ring groove is adapted to the length between the two elastic rings, and the elastic feet of the elastic rings abut against the axial end of the limiting ring groove.

5. A steering column with a high natural frequency according to claim 1, characterized in that: A bearing three is also provided between the output shaft and the housing, with bearing two and bearing three distributed on both sides of the output shaft.

Images