Steering engine rack deflection measuring tool

Abstract

The utility model relates to the technical field of steering systems, in particular to a deflection measuring tool for a rack of a steering engine. A steering engine rack deflection measuring tool comprises a bottom plate, a fixed end assembly and a load end assembly, and is characterized in that the fixed end assembly, an input end assembly, a servo end assembly and the load end assembly are sequentially connected to the bottom plate from left to right; bases of the fixed end assembly, the input end assembly, the servo end assembly and the load end assembly are connected with the bottom plate through bolts. The input end assembly is a pressing block fixing tool, and the servo end assembly is a pressing block fixing tool or a parallel shaft type steering engine servo tool. Compared with the prior art, the tool for measuring the deflection of the rack of the steering engine is convenient for carrying out research on the deflection of the rack, provides data support for arrangement of the steering engine and type selection of gears and racks, and can measure the deflection of the racks of various types of steering engines including a double-gear type electronic steering engine and a parallel shaft type electric steering engine.

Description

Technical Field

[0001] This utility model relates to the field of steering system technology, specifically a tooling for measuring the deflection of a steering gear rack. Background Technology

[0002] With the development of vehicle technology, the subframe space layout, tire distance, and front axle load of vehicles are becoming increasingly larger, leading to higher market demands for steering gear design. One of the most critical performance parameters is rack deflection. Spatial layout forces the input and servo positions of the steering gear closer to the center of the vehicle, tire distance requires longer rack lengths, and front axle loads demand higher steering gear loads; all these parameters contribute to increasing rack deflection. Furthermore, there is currently a lack of design experience with long racks and input servo layouts in steering gears, and preliminary CAE calculations cannot accurately reflect the overall vehicle performance of such designs. This lack of testing experience poses a significant challenge to the early design of steering gears. Summary of the Invention

[0003] To overcome the shortcomings of the prior art, this utility model provides a tooling for measuring the deflection of a steering gear rack, which facilitates the study of rack deflection and provides data support for the layout of the steering gear and the selection of gears and racks.

[0004] To achieve the above objectives, a steering gear rack deflection measuring fixture is designed, comprising a base plate, a fixed end assembly, and a load end assembly. The fixture is characterized in that: from left to right, the fixed end assembly, input end assembly, servo end assembly, and load end assembly are sequentially connected to the base plate; the bases of the fixed end assembly, input end assembly, servo end assembly, and load end assembly are respectively connected to the base plate by bolts; the input end assembly is a pressure block fixing fixture, and the servo end assembly is a pressure block fixing fixture or a parallel shaft steering gear servo fixture.

[0005] The connection ports of the fixed-end component, the input component, and the servo component are on the same horizontal line.

[0006] The aforementioned pressure block fixing fixture includes a fixing fixture connecting base plate, a support fixing plate, a pressure block hole fixture, a rack support block, and a first fixing bolt. The bottom of the fixing fixture connecting base plate is connected to the base plate by bolts, and the top of the fixing fixture connecting base plate is connected to the support fixing plate. The pressure block hole fixture is connected to the support fixing plate. A through hole for penetrating the rack is provided in the middle of the pressure block hole fixture. A pressure block through hole for installing the pressure block assembly is provided on one side of the through hole, and a rack support block is provided on one side of the through hole.

[0007] The pressure block assembly is provided in the through hole of the pressure block. The pressure block assembly includes a pressure block assembly, a helical spring, and an adjusting nut. The front end of the pressure block assembly faces the through hole of the rack, and the tail end of the pressure block assembly is connected to the adjusting nut. A helical spring is provided between the tail end of the pressure block assembly and the adjusting nut.

[0008] The rack support block is connected to the pressure block hole tooling by the first fixing bolt.

[0009] The parallel-axis steering gear servo fixture includes a servo fixture connecting base plate, a left clamp of the ball nut assembly, a right clamp of the ball nut assembly, and a second fixing bolt. The bottom of the servo fixture connecting base plate is connected to the base plate by bolts, the top of the servo fixture connecting base plate is connected to the left clamp of the ball nut assembly, and the right side of the left clamp of the ball nut assembly is connected to the right clamp of the ball nut assembly by the second fixing bolt.

[0010] The upper part of the left clamp of the ball nut assembly is a cylindrical structure, and the right clamp of the ball nut assembly is an annular structure. The outer edge of the right clamp of the ball nut assembly is evenly distributed with several second fixing bolts to connect to the upper outer edge of the left clamp of the ball nut assembly.

[0011] Compared with the prior art, this utility model provides a tooling for measuring the deflection of a steering gear rack, which facilitates the study of rack deflection and provides data support for the layout of steering gears and the selection of gears and racks. It can realize the measurement of rack deflection of various types of steering gears, including dual-gear electronic steering gears and parallel-axis electric steering gears. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the rack deflection measurement method for a dual-gear power steering system according to this utility model.

[0013] Figure 2 This is a schematic diagram of the rack deflection measurement method for parallel shaft power steering systems according to this utility model.

[0014] Figure 3 This is a three-dimensional view of the fixing fixture structure for the pressure block in this utility model.

[0015] Figure 4 This is a top cross-sectional view of the installation of the pressure block fixing fixture of this utility model.

[0016] Figure 5 This is a side cross-sectional view of the installation of the pressure block fixing tool of this utility model.

[0017] Figure 6 This is a perspective view of the parallel shaft steering gear servo tooling structure in this utility model.

[0018] Figure 7 This is a top cross-sectional view of the parallel shaft steering gear servo fixture installation in this utility model. Detailed Implementation

[0019] The present invention will be further described below with reference to the accompanying drawings.

[0020] like Figure 1 , Figure 2 As shown, from left to right, the base plate 1 is connected to the fixed end assembly 2, the input end assembly 4, the servo end assembly 6, and the load end assembly 9. The bases of the fixed end assembly 2, the input end assembly 4, the servo end assembly 6, and the load end assembly 9 are respectively connected to the base plate 1 by bolts 7. The input end assembly 4 is a pressure block fixing fixture, and the servo end assembly 6 is a pressure block fixing fixture or a parallel shaft steering gear servo fixture.

[0021] The connection ports of the fixed-end component 2, the input-end component 4, and the servo-end component 6 are on the same horizontal line.

[0022] like Figures 3 to 5 As shown, the clamping block fixing fixture includes a fixing fixture connecting base plate, a support fixing plate, a clamping block hole fixture, a rack support block, and a first fixing bolt. The bottom of the fixing fixture connecting base plate 4.1 is connected to the base plate 1 by bolts 7, and the top of the fixing fixture connecting base plate 4.1 is connected to the support fixing plate 4.2. The clamping block hole fixture 4.3 is connected to the support fixing plate 4.2. A through hole 4.6 for penetrating the rack is provided in the middle of the clamping block hole fixture 4.3. A clamping block through hole 4.7 for installing the clamping block assembly is provided on one side of the through hole 4.6. A rack support block 4.4 is provided on one side of the through hole 4.6.

[0023] A pressure block assembly is provided inside the pressure block through hole 4.7. The pressure block assembly includes a pressure block assembly, a helical spring, and an adjusting nut. The front end of the pressure block assembly 4.8 faces the through hole 4.6 of the rack. The tail end of the pressure block assembly 4.8 is connected to the adjusting nut 4.9. A helical spring 4.10 is provided between the tail end of the pressure block assembly 4.8 and the adjusting nut 4.9.

[0024] The rack support block 4.4 is connected to the pressure block hole tooling 4.3 by the first fixing bolt 4.5.

[0025] The pressure block fixing fixture is used on the input and servo ends of the dual-gear electronic steering gear and the input end of the parallel-axis electric steering gear. The fixing fixture connecting base plate 4.1 is used to fix the pressure block fixing fixture on the base plate 1. The supporting fixing plate 4.2 is used to install the pressure block hole fixture 4.3. The pressure block hole fixture 4.3 is concentric with the supporting fixing plate 4.2 and can rotate on the supporting fixing plate 4.2 to adjust the rack support position, closely approximating the actual steering gear layout. The pressure block hole fixture 4.3 is used to install the steering gear gear clearance adjustment device to simulate the steering gear's performance under different pressure block preload and clearance conditions. The rack support block 4.4 is a structure used to top the rack, simulating the gear and rack meshing structure.

[0026] like Figure 6 , Figure 7As shown, the parallel shaft steering gear servo fixture includes a servo fixture connecting base plate, a left clamp of the ball nut assembly, a right clamp of the ball nut assembly, and a second fixing bolt. The bottom of the servo fixture connecting base plate 6.1 is connected to the base plate 1 by bolt 7, and the top of the servo fixture connecting base plate 6.1 is connected to the left clamp of the ball nut assembly 6.2. The right side of the left clamp of the ball nut assembly 6.2 is connected to the right clamp of the ball nut assembly 6.3 by the second fixing bolt 6.4.

[0027] The upper part of the left clamp 6.2 of the ball nut assembly is a cylindrical structure, and the right clamp 6.3 of the ball nut assembly is a circular structure. The outer edge of the right clamp 6.3 of the ball nut assembly is evenly distributed with several second fixing bolts 6.4 to connect with the upper outer edge of the left clamp 6.2 of the ball nut assembly.

[0028] The servo tooling connecting base plate 6.1 of the parallel shaft steering gear servo tooling is used to fix the tooling on the base plate 1. The left clamp 6.2 of the ball nut assembly is machined with a fixing mounting hole that mates with the ball nut assembly of the parallel shaft steering gear. The right clamp 6.3 of the ball nut assembly is machined with a fixing mounting hole that mates with the ball nut assembly of the parallel shaft steering gear. The left clamp 6.2 and the right clamp 6.3 of the ball nut assembly are assembled by the second fixing bolt 6.4 to fix the ball nut assembly.

[0029] like Figures 2 to 5As shown, when this utility model is used for measuring the rack deflection of a dual-gear power steering system, both the input end component 4 and the servo end component 6 of the measuring fixture are pressure block fixing fixtures. The distance L1 from the input end component 4 to the fixed end component 2 and the distance L2 from the servo end component 6 to the fixed end component 2 can be adjusted according to the research needs by moving the position of the fixing fixture connecting base plate 4.1 on the base plate 1. After confirming the position of the support fixing plate 4.2 of the input end component 4 and the servo end component 6, the rack assembly 5 is placed after passing through the center hole of the support fixing plate 4.2 and the pressure block hole fixture 4.3. The left end of the rack assembly 5 is connected and fixed to the fixed end assembly 2 via the fixed end connecting fixture 3. The rack support block 4.4 is fixed to the pressure block hole fixture 4.3 by the first fixing bolt 4.5. The pressure block hole fixture 4.3 can be selected and adapted according to the diameter of the rack assembly 5. The angle of the pressure block hole in the pressure block fixture 4.3 can be adjusted according to research needs. After the angle is adjusted, the pressure block hole fixture 4.3 is fixed to the support fixing plate 4.2 by bolts. After confirming the position and angle of the pressure block hole, the pressure block assembly 4.8 and the helical spring 4.10 are installed. The performance parameters of the elastic damping element can be selected according to research needs. The pressure block is locked with the adjusting nut 4.9 to complete the assembly of the input end assembly 4 and the servo end assembly 6. Finally, the end of the rack assembly 5 and the load end assembly 9 are connected and fixed via the servo end connecting fixture 8. The load end assembly 9 can adjust the load F applied to the end of the rack assembly 5 as needed, and is equipped with a displacement sensor that can measure and record the displacement x of the end of the rack assembly 5 under the load applied by the load end assembly 9.

[0030] like Figure 1 , Figures 2 to 7 As shown, when this utility model is used for measuring the rack deflection of a parallel-axis power steering system, the input end component 4 of the measuring fixture is a pressure block fixing fixture, and the servo end component 6 is a parallel-axis power steering system servo fixture. The servo end of the parallel-axis power steering system is a ball nut assembly, which needs to be fixed using a ball nut fixing fixture. The installation method is as follows: the left clamp 6.2 of the ball nut assembly determines the position L2 of the parallel-axis power steering system servo fixture according to the steering system parameters or research needs, and the servo fixture is fixed to the base plate 6.1 on the base plate 1 by bolts. The rack assembly 5 consists of a rack and a ball nut assembly 10, wherein the ball nut assembly 10 can be moved in the raceway area of ​​the rack assembly 5 to be adjusted to the L2 position required for the research. The ball nut assembly 10 is placed in the left clamp 6.2 of the ball nut assembly, installed and fitted with the right clamp 6.3 of the ball nut assembly, and finally fixed with the second fixing bolt 6.4.

[0031] Example 1: Preliminary verification of rack deflection based on the surrounding layout of the customer in the early design phase of a dual-gear power steering system:

[0032] In the early design phase, based on the customer's surroundings and needs, the distance from the input end of the dual-gear power steering digital model to the left end face of the rack is L1, and the pressure block angle at the input end is θ1. The distance from the servo end to the left end face of the rack is L2, and the pressure block angle at the servo end is θ2. Calculations show that the maximum load on the rack end is F. In the early stages of the project, it is impossible to create a rapid prototype of this design to understand the rack deflection performance. Therefore, the rack deflection research and measurement fixture for the dual-gear power steering proposed in this invention can be used to assess the performance of this design in a real-world scenario. First, the rack deflection study and measurement fixture for the dual-gear power steering system is installed according to the specific implementation method and design parameters. Then, the output force of the loading end of the fixture is set according to the calculated maximum load F at the rack end. Simultaneously, the displacement sensor at the loading end measures the displacement x at the rack end. The data obtained from the experiment represents the rack deflection performance of the initial steering system layout design. This parameter can be used to determine whether there will be interference between the rack and the housing during vehicle operation. It can also be compared with the experimental and market data of existing projects to infer the reliability of the current design. If the experimental results do not meet the requirements, the positions of the input and servo ends can be modified. After multiple experiments, a suitable rack deflection can be found, and the steering system design can be improved based on the experimental parameters.

[0033] Example 2 examines the influence of the deflection of the rack and pinion system in a parallel-axis power steering system on the distance and direction of the input end support point, the distance of the servo end support point, the preload of the two support points, and the load on the rack. This provides experimental data for establishing a parameterized numerical model of the rack and pinion system deflection in a gear-type power steering system.

[0034] When developing a new ball nut assembly, to fully understand its performance and impact on rack deflection, benchmarking through experiments and CAE calculations is necessary. The rack deflection research and measurement fixture for the parallel-axis power steering system proposed in this invention can be used to collect experimental data and benchmark it against CAE calculation data. This data can then be used to correct and optimize the CAE calculation model, improving its accuracy and increasing the development efficiency of subsequent projects. First, following the specific implementation method, complete the installation of the new rack assembly and the rack deflection research and measurement fixture for the parallel shaft power steering system. The distance from the input end to the left end face of the rack, which significantly affects rack deflection, is L1; the pressure block angle at the input end is θ1; the distance from the servo end to the left end face of the rack is L2; ​​and the applied load F at the loading end is designed with a gradient table. Experiments can be designed according to the DOE experimental method. Adjustments to the rack deflection research and measurement fixture for the parallel shaft power steering system are made based on different parameters to obtain the rack end displacement x under different parameters. Based on the data, the rack deflection variation curve G(L, θ, F) under different parameters can be plotted. Based on these experimental data and curves, CAE calculation data can be benchmarked, and the CAE model can be optimized. Alternatively, parametric modeling of the rack deflection under the new ball nut assembly can be completed according to the experimental curves, laying the foundation for positive development of subsequent application projects.

Claims

1. A fixture for measuring the deflection of a steering gear rack, comprising a base plate, a fixed end assembly, and a load end assembly, characterized in that: The base plate (1) is connected from left to right to the fixed end assembly (2), the input end assembly (4), the servo end assembly (6), and the load end assembly (9). The bases of the fixed end assembly (2), the input end assembly (4), the servo end assembly (6), and the load end assembly (9) are respectively connected to the base plate (1) with bolts (7). The input end assembly (4) is a pressure block fixing fixture, and the servo end assembly (6) is a pressure block fixing fixture or a parallel shaft steering gear servo fixture.

2. The steering gear rack deflection measuring fixture according to claim 1, characterized in that: The connection ports of the fixed end component (2), the input end component (4), and the servo end component (6) are on the same horizontal line.

3. The steering gear rack deflection measuring fixture according to claim 1, characterized in that: The fixing fixture for the pressure block includes a fixing fixture connecting base plate, a support fixing plate, a pressure block hole fixture, a rack support block, and a first fixing bolt. The bottom of the fixing fixture connecting base plate (4.1) is connected to the base plate (1) by bolts (7). The top of the fixing fixture connecting base plate (4.1) is connected to the support fixing plate (4.2). The support fixing plate (4.2) is connected to the pressure block hole fixture (4.3). A through hole (4.6) for penetrating the rack is provided in the middle of the pressure block hole fixture (4.3). A pressure block through hole (4.7) for installing the pressure block assembly is provided on one side of the through hole (4.6). A rack support block (4.4) is provided on one side of the through hole (4.6).

4. The steering gear rack deflection measuring fixture according to claim 3, characterized in that: The pressure block through hole (4.7) is provided with a pressure block assembly, which includes a pressure block assembly, a helical spring, and an adjusting nut. The front end of the pressure block assembly (4.8) faces the through hole (4.6) of the rack, and the tail end of the pressure block assembly (4.8) is connected to the adjusting nut (4.9). A helical spring (4.10) is provided between the tail end of the pressure block assembly (4.8) and the adjusting nut (4.9).

5. The steering gear rack deflection measuring fixture according to claim 3, characterized in that: The rack support block (4.4) is connected to the pressure block hole tool (4.3) by the first fixing bolt (4.5).

6. The steering gear rack deflection measuring fixture according to claim 1, characterized in that: The parallel shaft steering gear servo fixture includes a servo fixture connecting base plate, a left clamp of the ball nut assembly, a right clamp of the ball nut assembly, and a second fixing bolt. The bottom of the servo fixture connecting base plate (6.1) is connected to the base plate (1) by bolts (7). The top of the servo fixture connecting base plate (6.1) is connected to the left clamp of the ball nut assembly (6.2). The right side of the left clamp of the ball nut assembly (6.2) is connected to the right clamp of the ball nut assembly (6.3) by the second fixing bolt (6.4).

7. The steering gear rack deflection measuring fixture according to claim 6, characterized in that: The upper part of the left clamp (6.2) of the ball nut assembly is a cylindrical structure, and the right clamp (6.3) of the ball nut assembly is an annular structure. The outer edge of the right clamp (6.3) of the ball nut assembly is evenly distributed with several second fixing bolts (6.4) to connect with the upper outer edge of the left clamp (6.2) of the ball nut assembly.

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