Steering gear housing structure

Abstract

The utility model discloses a steering machine shell body structure, include: rack pipe wall, drive gear pipe wall, first bushing mounting hole, second bushing mounting hole and sensor end mounting hole, steering machine shell body structure is respectively between drive gear pipe wall with sensor end mounting hole and between drive gear pipe wall with second bushing mounting hole rack pipe wall outer periphery is provided with first stiffener assembly and second stiffener assembly. The utility model discloses compared with traditional increase circular pipe wall thickness can better satisfy the strength requirement and life requirement of impact working condition and fatigue working condition.

Description

Technical Field

[0001] This utility model relates to automotive steering systems, and in particular to a steering gear housing structure. Background Technology

[0002] With the widespread adoption of intelligent driving, the diverse travel scenarios for family sedans and SUVs have made the operating conditions of steering systems more complex and varied. While considering the comfort and practicality of steering operations, it is even more crucial to prioritize the safety of the steering gear housing under high torque and rapid steering reversal conditions. Therefore, the design of the steering gear housing needs to be lengthened and thickened to meet the strength requirements under various complex operating conditions. However, an excessively long housing increases the lever arm, thereby increasing bending moment and torque, thus increasing the risk of housing cracking. An excessively thick housing, on the other hand, increases product cost and may even increase fuel consumption in gasoline vehicles and affect the efficiency of electric vehicles. Therefore, to avoid severe yielding or cracking of the housing under harsh conditions such as high rack force or high torque, a steering gear housing structure that simultaneously meets the requirements of structural strength and lightweight design has been designed. Summary of the Invention

[0003] This invention designs a steering gear housing structure that meets structural strength requirements without increasing costs, thereby avoiding the problem of housing cracking.

[0004] To solve the above-mentioned technical problems, this utility model provides a steering gear housing structure, including: rack tube wall, drive gear tube wall, first bushing mounting hole, second bushing mounting hole and sensor end mounting hole. The steering gear housing structure has a first reinforcing rib assembly and a second reinforcing rib assembly respectively provided on the outer periphery of the rack tube wall between the drive gear tube wall and the sensor end mounting hole and between the drive gear tube wall and the second bushing mounting hole.

[0005] Preferably, the first reinforcing rib assembly consists of an I-beam rib, a flat rib, and a first reinforcing rib.

[0006] Preferably, the flange of the I-shaped rib is parallel to the first reinforcing rib, the flange of the I-shaped rib is symmetrical on both sides, the web of the I-shaped rib is disposed on the outer periphery of the rack tube wall, and the web of the I-shaped rib is in the same plane as the first reinforcing rib. The first reinforcing rib is parallel to the rack axis, the flat rib structure is parallel to the first reinforcing rib, and the flat rib structure is symmetrical on both sides.

[0007] Preferably, the flat rib structure is a double-layer flat rib structure.

[0008] Preferably, the second reinforcing rib assembly consists of a T-shaped cross-section rib and a second reinforcing rib.

[0009] Preferably, the flange of the T-shaped cross-section rib is parallel to the second reinforcing rib, and the flange of the T-shaped cross-section rib transitions in a transverse S-shape in the direction of the rack axis. The web of the T-shaped cross-section rib is disposed on the outer periphery of the rack tube wall, and the web of the T-shaped cross-section rib is perpendicular to the second reinforcing rib, while the second reinforcing rib is parallel to the direction of the rack axis.

[0010] Preferably, the second reinforcing rib assembly further includes auxiliary reinforcing ribs.

[0011] Preferably, the T-shaped cross-section stiffener web is located outside the pipe wall and perpendicular to the auxiliary stiffener, and the auxiliary stiffener is parallel to the direction of the rack axis.

[0012] This invention, while maintaining a relatively thin wall thickness and not significantly increasing weight, can withstand at least four times the load. During vibration, more effective mass participates in the vibration, reducing the vibration frequency. Simultaneously, it avoids excessively thick local areas, better preventing casting defects caused by uneven cooling during the casting process. Compared to traditional methods of increasing the wall thickness of circular tubes, it better meets the strength and lifespan requirements under impact and fatigue conditions. Attached Figure Description

[0013] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments: Figures 1-2 This is a schematic diagram of the overall structure of Example 1.

[0014] Figure 3 This is a cross-sectional view of the I-shaped reinforcement in Example 1.

[0015] Figure 4 This is a partial enlarged view of Example 1.

[0016] Figure 5 This is a cross-sectional view of the T-shaped reinforcement in Example 2.

[0017] Figure 6-7 This is a partial enlarged view of Example 2.

[0018] Explanation of reference numerals in the attached figures 1-Bushing mounting hole; 2-Sensor end; 3-Servo end; 4-T-section rib; 5-Second reinforcing rib; 6-Flat plate rib structure; 7-First reinforcing rib; 8-I-shaped rib; 9-Rack tube wall; 10-Auxiliary reinforcing rib; 11-Drive gear tube wall; 12-Avoidance position. Detailed Implementation

[0019] The following specific embodiments illustrate the implementation of this utility model. Those skilled in the art can fully understand other advantages and technical effects of this utility model from the content disclosed in this specification. This utility model can also be implemented or applied through different specific embodiments, and the details in this specification can also be applied based on different viewpoints, with various modifications or changes made without departing from the overall design concept of the invention. It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments can be combined with each other. The following exemplary embodiments of this utility model can be implemented in many different forms and should not be construed as being limited to the specific embodiments set forth herein. It should be understood that these embodiments are provided to make the disclosure of this utility model thorough and complete, and to fully convey the technical solutions of these exemplary embodiments to those skilled in the art.

[0020] To meet the above requirements, this utility model adopts a completely new structural design. Figure 1 As shown), it includes: bushing mounting hole 1, sensor unit end 2, motor end 3, T-shaped cross-section rib 4, second reinforcing rib structure 5, flat rib structure 6, first reinforcing rib structure 7, I-shaped rib structure 8, rack tube wall 9, and auxiliary reinforcing rib 10. Example 1

[0021] Combination Figures 1 to 3 The I-shaped rib flange is parallel to the second reinforcing rib 5, and the flanges are symmetrical on both sides. The web of the I-shaped rib is located outside the pipe wall 9, and the web is on the same plane as the first reinforcing rib 7. The first reinforcing rib 7 is parallel to the axis of the rack. The flat rib structure 6 is parallel to the second reinforcing rib 5, and the flat rib structure 6 is symmetrical on both sides.

[0022] like Figure 4As shown, the I-beam ribs are mainly arranged between the drive gear tube wall and the sensor mounting hole. Under various working conditions, due to the particularly large load along the axis of the drive gear tube wall, a particularly large stress concentration will occur between the drive gear tube wall and the bushing mounting hole. In particular, the overall elastic strength calculation result at the location of rack tube wall 9 exceeds the evaluation standard by up to 3.7 times, and the area of ​​stress concentration is huge. According to CAE calculation, increasing the wall thickness of rack tube to 7mm still cannot meet the shell strength evaluation standard. If it is further thickened, it will greatly increase the cost and the risk of casting defects. In addition, the clearance position 12 cannot be thickened because it needs to maintain the regulatory clearance with surrounding parts. Therefore, a combination of I-beam cross-section, thin-walled circular cross-section and flat plate cross-section was designed to increase the strength and bending stiffness of the shell. Based on simple theoretical calculations, the combined section of I-beams, thin-walled hollow circular ribs, and flat ribs increases the bending coefficient and torsional section coefficient by 6.2 times compared to a 7mm thick hollow circular section, and by 9.4 times compared to a 3.5mm thick hollow circular section. Calculations show that, without significantly increasing weight while maintaining structural strength, the combined section needs to be 220mm long along the pipe wall axis. Therefore, compared to typical projects, this structure can withstand a 4-fold increase in load. Furthermore, modal analysis reveals that, compared to structures that only increase shell wall thickness, the structure designed in this patent has a greater effective mass involved in vibration, effectively reducing the vibration frequency.

[0023] This embodiment takes a steering gear housing as an example, and strength impact tests were conducted using both a traditional structure and a novel structure. CAE strength calculations showed that using the novel structure designed in this patent, the stress value at stress-risk location 9 of the housing wall was reduced by approximately four times. Simultaneously, compared to similar housings, the weight increase was only about 85g, achieving the high strength and lightweight requirements of the housing.

[0024] Compared to traditional structures that increase wall thickness, the combined structure of I-beam ribs, hollow circles, and flat ribs in this embodiment can withstand at least four times more load while maintaining a relatively thin wall thickness and without significantly increasing weight. During vibration, more effective mass participates in the vibration, reducing the vibration frequency. Simultaneously, it avoids excessively thick local areas, better preventing casting defects caused by uneven cooling during the casting process. Compared to traditional methods of increasing the wall thickness of circular tubes, this embodiment better meets the strength and lifespan requirements under impact and fatigue conditions. Example 2

[0025] Combination Figure 1 , Figure 2 and Figure 5As shown, the flange of the T-section reinforcement 4 is parallel to 5, and the flange transitions in a transverse S-shape along the rack axis. The web of the T-section reinforcement 4 is located outside the pipe wall 9, and the web is perpendicular to the auxiliary reinforcing rib 10, which is parallel to the rack axis. Combined with... Figure 1 and Figure 2 The flange of the I-beam rib 8 is parallel to the second reinforcing rib 5, and the flanges of the I-beam rib 8 are symmetrical on both sides. The web of the I-beam rib is located outside the pipe wall 9, and the web is on the same plane as the first reinforcing rib 7. The first reinforcing rib is parallel to the axis of the rack. The flat rib is parallel to the second reinforcing rib 5, and the flat rib is symmetrical on both sides.

[0026] like Figure 6-7 The T-shaped ribs shown are mainly arranged between the drive gear tube wall and the second bushing mounting holes. Under various working conditions, due to the particularly large load along the axis of the drive gear tube wall, a particularly large stress concentration will occur between the drive gear tube wall and the first and second bushing mounting holes. In particular, the calculated elastic strength at the locations of T-shaped rib 4, rack tube wall 9, and second reinforcing rib 5 exceeds the evaluation standard by 1.7 times, and the area of ​​stress concentration is huge. CAE calculations show that the wall thickness of the rack tube needs to be increased to 7mm to meet the shell strength evaluation standard. Excessive wall thickness will increase costs and the risk of casting defects. Simple theoretical calculations show that the combined section of the T-shaped section and the thin-walled hollow circular section increases the bending coefficient by 30% and the torsional section coefficient by 30% compared to the 7mm thick hollow circular section. By setting the T-shaped section ribs with an S-shaped transition and combining them with reinforcing ribs, the load-bearing capacity can be increased by 70% compared to general projects. At the same time, modal analysis shows that compared to structures that only increase the shell wall thickness, the structure designed in this embodiment has more effective mass participating in vibration, which can effectively reduce the vibration frequency.

[0027] This embodiment takes a steering gear housing as an example. Strength impact tests were conducted using both the traditional and novel structures. CAE strength calculations showed that, after using the novel structure designed in this patent, the stress value at the risk location of the housing (T-shaped rib 4) was reduced by approximately 85%; the stress value at the risk location of the housing (rack tube wall 9) was reduced by approximately 70%; and the stress value at the risk location of the housing (second reinforcing rib 5) was reduced by approximately 75%. Simultaneously, the housing weight increased by less than 1%, achieving the lightweight requirement for the housing.

[0028] Compared to traditional structures that increase wall thickness, the T-shaped rib structure designed in this embodiment can withstand at least four times more load while maintaining a relatively thin wall thickness and without significantly increasing weight. During vibration, more effective mass participates in the vibration, reducing the vibration frequency. Simultaneously, it avoids excessively thick local areas, better preventing casting defects caused by uneven cooling during the casting process. Compared to traditional methods of increasing the wall thickness of circular tubes, this embodiment better meets the strength and lifespan requirements under impact and fatigue conditions.

[0029] The present invention has been described in detail above through specific embodiments and examples, but these are not intended to limit the present invention. Many modifications and improvements can be made by those skilled in the art without departing from the principles of the present invention, and these should also be considered within the scope of protection of the present invention.

Claims

1. A steering gear housing structure, characterized in that, include: The steering gear housing structure includes a rack tube wall, a drive gear tube wall, a first bushing mounting hole, a second bushing mounting hole, and a sensor end mounting hole. A first reinforcing rib assembly and a second reinforcing rib assembly are respectively provided on the outer periphery of the rack tube wall between the drive gear tube wall and the sensor end mounting hole, and between the drive gear tube wall and the second bushing mounting hole.

2. The steering gear housing structure according to claim 1, characterized in that, The first reinforcing rib assembly includes an I-beam, a flat rib, and a first reinforcing rib.

3. The steering gear housing structure according to claim 2, characterized in that, The flange of the I-shaped rib is parallel to the first reinforcing rib, the flange of the I-shaped rib is symmetrical on the left and right sides, the web of the I-shaped rib is set on the outer periphery of the rack tube wall, and the web of the I-shaped rib is on the same plane as the first reinforcing rib. The first reinforcing rib is parallel to the rack axis, the flat plate rib structure is parallel to the first reinforcing rib, and the flat plate rib structure is symmetrical on the left and right sides.

4. The steering gear housing structure according to claim 3, characterized in that, The flat rib structure is a double-layer flat rib structure.

5. The steering gear housing structure according to claim 1, characterized in that, The second reinforcing rib assembly includes a T-shaped cross-section rib and a second reinforcing rib.

6. The steering gear housing structure according to claim 5, characterized in that, The flange of the T-shaped cross-section reinforcement is parallel to the second reinforcing rib, and the flange of the T-shaped cross-section reinforcement transitions in a transverse S-shape in the direction of the rack axis. The web of the T-shaped cross-section reinforcement is located on the outer periphery of the rack tube wall, and the web of the T-shaped cross-section reinforcement is perpendicular to the second reinforcing rib, while the second reinforcing rib is parallel to the direction of the rack axis.

7. The steering gear housing structure according to claim 5, characterized in that, The second reinforcing rib assembly also includes auxiliary reinforcing ribs.

8. The steering gear housing structure according to claim 7, characterized in that, The T-shaped cross-section reinforcement web is located outside the pipe wall and is perpendicular to the auxiliary reinforcement, which is parallel to the direction of the rack axis.

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