High-performance steering column and performance quantification method thereof
By designing a high-performance steering column including a collapse mechanism, a column tube mechanism and a bracket mechanism in the automotive steering column, the problem of insufficient performance of the collapse mechanism in the prior art is solved, and higher frequency stiffness and collapse are achieved Performance and precisely control the collapse force through quantitative methods to reduce costs and cycles.
Patent Information
- Application Number
- CN202411282622.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-13
- Publication Date
- 2025-01-07
AI Technical Summary
The existing automobile steering column has insufficient performance in the collapse mechanism during collision, resulting in a high risk of driver injury and a lack of effective sex energy control methods.
A high-performance steering column including a collapse mechanism, a column tube mechanism, a bracket mechanism and a steering shaft mechanism is designed. The frequency of the pipe column is raised through components such as energy suction belts, rivets, handles, toothed groove brackets and clamping teeth. Stiffness and collapse performance, and provide sexual energy-based methods to calculate collapse force and bearing pull-off force.
It significantly improves the collapse, frequency and stiffness performance of the steering column, reduces R&D and production costs, shortens the R&D cycle, and achieves precise control of the collapse stroke force.
Smart Images
Figure CN119262048A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of automobile steering systems, and in particular to a high-performance steering column equipped with a collapse mechanism capable of improving the frequency stiffness characteristics of the column and a performance quantification method thereof. Background Art
[0002] Automobile safety is one of the three major themes of sustainable development of the current automobile industry. In the process of automobile production and research and development, its active and passive safety is particularly important. According to the latest traffic accident statistics and the results of automobile collision tests, when a car collides head-on, the steering mechanism is the main component that causes driver injury, and the crush mechanism on the steering column is the most critical component to prevent driver injury. Therefore, it is particularly important to develop a steering column equipped with a crush mechanism that has good safety performance and can improve column frequency stiffness and other performance. Finding a quantitative control method for various performances such as crush force is the core content of the development of high-performance steering columns. The high-performance steering column involved in this patent has been verified to have a frequency stiffness performance far exceeding that of a steering column equipped with a conventional crush mechanism. Summary of the invention
[0003] In order to solve the above technical problems, the present invention provides a high-performance steering column, including a collapse mechanism, a column tube mechanism, a bracket mechanism and a steering shaft mechanism; the top of the steering shaft mechanism is connected to the steering wheel and is connected to the column tube mechanism through a bearing; the upper part of the bracket mechanism is connected to the protective cover and is connected to the column tube mechanism through the collapse mechanism.
[0004] Preferably, the column tube mechanism includes an upper column tube and a lower column tube; the upper column tube and the lower column tube are connected to the steering shaft mechanism through bearings, wherein the upper column tube can realize axial movement in the lower column tube; the lower column tube is connected to the handle and the bracket mechanism, and the end is connected to the whole vehicle through the steering shaft mechanism.
[0005] Preferably, the bracket mechanism includes a U-shaped bracket, an upper base plate and a lower base plate; wherein the upper base plate is fixedly connected to the U-shaped bracket and is used for clamping between the upper column tube and the lower column tube, and the upper base plate and the lower base plate are respectively connected to the protective cover by bolts.
[0006] Preferably, the collapse mechanism includes an energy absorbing belt, a rivet, a handle, a long bolt, a toothed groove bracket and a latch; wherein the energy absorbing belt is fixedly connected to the latch and is riveted to the lower column tube by means of rivets; the toothed groove bracket is fixedly connected to the upper column tube; when the handle is locked, the end of the handle contacts the top of the latch and presses the latch into the toothed groove bracket to complete the connection of the collapse mechanism.
[0007] Preferably, the bearing pressing area where the upper column tube is connected to the steering shaft mechanism through the bearing adopts interference contact; the top of the upper column tube adopts a multi-anchor point pressing method to enhance the bearing pull-off force.
[0008] Preferably, a toothed groove bracket is welded on the upper column tube.
[0009] Preferably, the lower column tube is made of aluminum alloy, and the bracket mechanism is made of steel.
[0010] Preferably, the rigidity of the two sides of the U-shaped bracket is different, and a groove is performed on the side with lower rigidity.
[0011] The present invention also provides a performance quantification method for a steering column, the performance quantification method comprising quantifying the column collapse force and the column bearing pull-off force, the column collapse force comprising a collapse peak force and a collapse continuous force; the steering column is the steering column described in any one of claims 1 to 8.
[0012] Preferably, the calculation method of the collapse peak force is: 1 =0.85n×σ×A, where F 1 is the peak collapse force, n is the number of rivets, σ is the tensile strength of the rivet, and A is the shear surface area.
[0013] Preferably, the method for calculating the collapse duration is: Among them, F 3 is the collapse duration, k is the deformation coefficient of the energy absorption band, R m is the yield strength of the energy absorption band material, l is the cross-sectional width of the energy absorption band, d is the cross-sectional thickness of the energy absorption band, R is the bending radius of the energy absorption band, F 2 is the column-tube friction force.
[0014] Preferably, the column tube friction force is calculated by: Where μ is the friction coefficient between the column and the tube, K 1 is the clamping efficiency, K 0 is the tightening force coefficient, d is the nominal diameter of the thread, and T is the handle torque.
[0015] Preferably, the calculation method of the pull-off force of the pipe column bearing is: Where P is the pull-out force of the pipe column bearing, δ is the actual interference, D is the nominal value of the outer diameter of the contained part, Ra 1 , Ra 2 are the surface roughness of the two surfaces, σ is the yield strength of the material, and S is the pressing area of the upper column tube.
[0016] Compared with the prior art, the present invention can effectively reduce the research and development and production costs of the steering column, improve the collapse, frequency and stiffness performance of the column, shorten the development cycle of the steering column, and can accurately control the collapse force of the column collapse stroke. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments:
[0018] Figure 1 An exploded view of the high-performance steering column structure of Example 1 of the present invention;
[0019] Figure 2 A schematic diagram of a high-performance steering column provided in Example 1 of the present invention;
[0020] Figure 3 A top view of the high-performance steering column provided in Example 1 of the present invention.
[0021] Description of Reference Numerals
[0022] 1-upper column tube, 2-lower column tube, 3-upper steering shaft, 4-lower steering shaft, 5-lower base plate, 6-upper base plate, 7-U-shaped bracket, 8-lower bearing, 9-upper bearing, 10-handle, 11-long bolt, 12-grip, 13-energy absorption belt, 14-rivet, 15-toothed groove bracket, 16-axial soft limit. DETAILED DESCRIPTION
[0023] The following describes the implementation methods of the present invention through specific specific embodiments, and those skilled in the art can fully understand other advantages and technical effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through different specific implementation methods, and the details in this specification can also be applied based on different viewpoints, and various modifications or changes can be made without deviating from the overall design concept of the invention. It should be noted that the following embodiments and the features in the embodiments can be combined with each other in the absence of conflict. The following exemplary embodiments of the present invention can be implemented in a variety of different forms and should not be interpreted as being limited to the specific embodiments described herein. It should be understood that these embodiments are provided to make the disclosure of the present invention thorough and complete, and to fully convey the technical solutions of these exemplary specific embodiments to those skilled in the art.
[0024] Example 1
[0025] like Figures 1 to 3 As shown, this embodiment provides a high-performance steering column, including a collapse mechanism, a column tube mechanism, a bracket mechanism and a steering shaft mechanism; the top of the steering shaft mechanism is connected to the steering wheel and is connected to the column tube mechanism through a bearing; the upper part of the bracket mechanism is connected to the protective cover and is connected to the column tube mechanism through the collapse mechanism. The overall structure is relatively simple and the cost is low.
[0026] The steering shaft mechanism comprises an upper steering shaft 3 and a lower steering shaft 4 .
[0027] The column tube mechanism includes an upper column tube 1 and a lower column tube 2; the upper column tube 1 and the lower column tube 2 are connected to the steering shaft mechanism through bearings, wherein the upper column tube 1 can realize axial movement in the lower column tube 2; the lower column tube 2 is connected to the handle 10 and the bracket mechanism, and the end is connected to the whole vehicle through the steering shaft mechanism.
[0028] The bracket mechanism includes a U-shaped bracket 7, an upper base plate 6 and a lower base plate 5; wherein the upper base plate 6 is fixedly connected to the U-shaped bracket 7 and is used for clamping between the upper column tube 1 and the lower column tube 2, and the upper base plate 6 and the lower base plate 5 are respectively connected to the protective cover by bolts.
[0029] The collapse mechanism includes an energy absorbing belt 13, a rivet 14, a handle 10, a long bolt 11, a toothed groove bracket 15 and a clamping tooth 12. The energy absorbing belt 13 is connected to the clamping tooth 12 by welding, and is riveted to the lower column tube 2 by the rivet 14. The toothed groove bracket 15 is welded to the upper column tube 1 to improve the rigidity of the upper column tube, thereby improving the rigidity and frequency performance of the steering column. When the handle 10 is locked, the end of the handle will contact the top of the clamping tooth 12 and press the clamping tooth 12 into the toothed groove bracket 15 to complete the connection of the collapse mechanism. When the collapse begins, the upper column tube is subjected to pressure, and its toothed groove bracket will drive the clamping tooth to pull the energy absorbing belt to transfer the load to the rivet, and its stress accumulation will shear the rivet to provide the collapse peak force; at the same time, the upper column tube overcomes the deformation of the energy absorbing belt and the tube-to-tube friction force and begins to move axially, wherein the deformation force of the energy absorbing belt and the tube-to-tube friction force are the collapse continuous force.
[0030] The bearing (upper bearing 9) connected to the upper column tube and the steering shaft mechanism adopts interference contact in the press-fit area, and the top of the upper column tube adopts a multi-anchor press-fit method to improve the bearing pull-off force. And the toothed groove bracket is welded on the upper column tube, which can provide support for collapse on the one hand, and effectively improve the rigidity of the upper column tube on the other hand, thereby improving the overall frequency stiffness performance of the steering column.
[0031] The U-shaped bracket adopts the method of weakening one side and strengthening the other side to improve its clamping efficiency as much as possible without affecting the structural rigidity, and grooves are cut in the weakened area to improve the clamping efficiency.
[0032] Based on the resonant frequency in the mechanical system The column lower column tube provided by the present invention is made of aluminum alloy, and the bracket is made of steel, thereby improving the resonance frequency of the steering column and further improving the control comfort of the steering column.
[0033] Example 2
[0034] This embodiment provides a method for quantifying the performance of a steering column, the method comprising quantifying the column collapse force and the column bearing pull-off force, the column collapse force comprising the collapse peak force and the collapse continuous force.
[0035] The column collapse force is provided by the long bolt preload provided by the handle mechanism, which in turn generates a clamping force on the upper and lower column tubes, thereby providing column tube friction. At the same time, the end of the handle will contact the top of the clamping tooth and press the clamping tooth into the toothed groove bracket to complete the connection of the collapse mechanism. At the beginning of the collapse, the upper column tube is subjected to pressure, and its toothed groove bracket will drive the clamping tooth to pull the energy absorption belt to transfer the load to the rivet. The accumulated stress will shear the rivet and provide the collapse peak force; at the same time, the upper column tube overcomes the deformation of the energy absorption belt and the friction force of the tube and starts axial movement, and the deformation force of the energy absorption belt and the friction force of the tube are the continuous collapse force.
[0036] The peak collapse force can be controlled by the type and number of rivets: the tensile strength σ of different types of rivets is known, the shear strength τ of the rivet is 0.8×σ, and the shear force F under the rivet shear condition is q =τ×A, A is the shear surface area. Therefore, the peak collapse force F 1 =0.85n×σ×A, where n is the number of rivets.
[0037] The friction of the crush column is controlled by the torque of the handle: Where K 0 is the tightening force coefficient, generally taken as 0.25; d is the nominal diameter of the thread; F 0 is the preload force. The column tube friction force calculation formula is: Where μ is the friction coefficient between the column and the tube, which is usually taken as 0.2, K 1 is the clamping efficiency, generally 0.7. Therefore, the friction force of the column tube is the continuous force of collapse. The deformation force of the energy absorbing belt is controlled by the size of the energy absorbing belt. In summary, the collapse duration can be expressed as Among them, k is the deformation coefficient of the energy absorption band, R m is the yield strength of the energy absorption band material, l is the cross-sectional width of the energy absorption band, d is the cross-sectional thickness of the energy absorption band, and R is the bending radius of the energy absorption band.
[0038] The pull-off force of the tubular column bearing is divided into two parts: the interference friction force of the bearing tube wall and the yield plastic deformation force of the pressed-in area. Firstly, since the bearing is pressed-in with interference, its interference force generates friction during the pulling process. When the pulling force reaches the static friction limit, it begins to contact the pressed-in area of the upper column tube. If the pulling force continues to be applied, it begins to yield and produce plastic deformation, which leads to the pulling-off of the bearing. Therefore, the pull-off force of the tubular column bearing can be improved by adjusting the interference amount of the bearing and the pressed-in area of the upper column tube.
[0039] The interference friction force of the bearing tube wall is based on the thick-walled cylinder theory. The friction force is controlled by the actual interference amount, and the actual interference amount δ = the inner diameter expansion amount L1 of the containing part + the outer diameter reduction amount L2 of the contained part - the surface wiping amount L3 of the pressing method. L 3 =2*1.6*(Ra1 +Ra 2 ),in D is the nominal value of the outer diameter of the contained part. 1 D is the outer diameter of the containing part. 2 is the inner diameter of the contained part, Ra is the surface roughness, μ is the friction coefficient between the two, generally taken as 0.11, E1 is the elastic modulus of the containing part, E2 is the elastic modulus of the contained part, so the part controlled by the interference
[0040] The yield deformation force quantification method is that when the tension on the upper shaft is higher than the interference friction force of the bearing, the bearing begins to slide and contact the upper column tube pressing area until it produces yield deformation. The load P of this part is 2 =σ*S, where σ is the yield strength of the material and S is the pressing area of the upper column tube.
[0041] Column bearing pull-off force P = P 1 +P 2 .
[0042] The present invention has been described in detail above through specific implementation modes and embodiments, but these do not constitute limitations of the present invention. Without departing from the principles of the present invention, those skilled in the art may also make many variations and improvements, which should also be regarded as the protection scope of the present invention.
Claims
1. A high-performance steering column, characterized in that: It includes a collapse mechanism, a column tube mechanism, a bracket mechanism and a steering shaft mechanism; the top of the steering shaft mechanism is connected to the steering wheel and is connected to the column tube mechanism through a bearing; the upper part of the bracket mechanism is connected to the protective cover and is connected to the column tube mechanism through the collapse mechanism.
2. The high performance steering column according to claim 1, characterized in that: The column tube mechanism includes an upper column tube and a lower column tube; the upper column tube and the lower column tube are connected to the steering shaft mechanism through bearings, wherein the upper column tube can realize axial movement in the lower column tube; the lower column tube is connected to the handle and the bracket mechanism, and the end is connected to the whole vehicle through the steering shaft mechanism.
3. The high performance steering column according to claim 1, characterized in that: The bracket mechanism includes a U-shaped bracket, an upper base plate and a lower base plate; wherein the upper base plate is fixedly connected to the U-shaped bracket and is used for clamping between the upper column tube and the lower column tube, and the upper base plate and the lower base plate are respectively connected to the protective cover by bolts.
4. The high performance steering column according to claim 2, characterized in that: The collapse mechanism includes an energy absorbing belt, a rivet, a handle, a long bolt, a toothed groove bracket and a latch; the energy absorbing belt is fixedly connected to the latch and is riveted to the lower column tube through the rivet; the toothed groove bracket is fixedly connected to the upper column tube; when the handle is locked, the end of the handle contacts the top of the latch and presses the latch into the toothed groove bracket to complete the connection of the collapse mechanism.
5. The high performance steering column according to claim 2, characterized in that: The bearing pressing area where the upper column tube is connected to the steering shaft mechanism through the bearing adopts interference contact; the top of the upper column tube adopts a multi-anchor point pressing method to improve the bearing pull-off force.
6. The high performance steering column according to claim 4, characterized in that: A toothed groove bracket is welded on the upper column tube.
7. The high performance steering column according to claim 2, characterized in that: The lower column tube is made of aluminum alloy, and the bracket mechanism is made of steel.
8. The high performance steering column according to claim 3, characterized in that: The rigidity of the two sides of the U-shaped bracket is different, and a groove is performed on the side with low rigidity.
9. A method for quantifying the performance of a steering column, characterized in that: The performance quantification method includes quantification of the tubular column collapse force and tubular column bearing pull-off force, wherein the tubular column collapse force includes collapse peak force and collapse continuous force; The steering column is the steering column according to any one of claims 1 to 8.
10. The method for quantifying the performance of a steering column according to claim 9, characterized in that: The calculation method of the collapse peak force is: F1=0.85n×σ×A, wherein F1 is the collapse peak force, n is the number of rivets, σ is the tensile strength of the rivet, and A is the shear surface area.
11. The method for quantifying the performance of a steering column according to claim 9, characterized in that: The calculation method of collapse duration is: Where F3 is the collapse duration, k is the deformation coefficient of the energy absorption band, R m is the yield strength of the energy absorption band material, l is the cross-sectional width of the energy absorption band, d is the cross-sectional thickness of the energy absorption band, R is the bending radius of the energy absorption band, and F2 is the friction force of the column tube.
12. The method for quantifying the performance of a steering column according to claim 11, characterized in that: The calculation method of the column tube friction force is: Where μ is the friction coefficient between the column and the tube, K1 is the clamping efficiency, K0 is the tightening force coefficient, d is the nominal diameter of the thread, and T is the handle torque.
13. The method for quantifying the performance of a steering column according to claim 9, characterized in that: The calculation method of the pull-off force of the pipe column bearing is: Where P is the pull-out force of the column bearing, δ is the actual interference, D is the nominal value of the outer diameter of the contained part, Ra1 and Ra2 are the surface roughness of the two surfaces respectively, σ is the yield strength of the material, and S is the pressing area of the upper column tube.