A commercial vehicle drive axle housing stiffness simulation method

Abstract

The application relates to the field of drive axle housing rigidity calculation, and particularly discloses a commercial vehicle drive axle housing rigidity simulation method, which comprises the following steps: importing a drive axle housing bench original model into finite element analysis software; performing finite element configuration on the drive axle housing bench original model to construct a drive axle housing bench finite element model, including performing finite element processing on the drive axle housing bench original model, applying pre-tightening force to connecting bolts of a main reduction housing and a drive axle housing, and applying lateral friction force to a cylindrical roller at an axle head of the drive axle housing; performing finite element simulation calculation on the drive axle housing bench finite element model to output a drive axle housing rigidity value. In the finite element analysis, pre-tightening force is applied to the bolts, and lateral friction force is applied to the cylindrical roller at the axle head, so that the accuracy of the finite element analysis is improved.

Description

Technical Field

[0001] This invention relates to the field of drive axle housing stiffness calculation, and more specifically to a method for simulating the stiffness of a commercial vehicle drive axle housing. Background Technology

[0002] As the main load-bearing and force-transmitting assembly, the drive axle is subjected to complex forces and large loads during the force transmission process. The drive axle transmits the road load to the vehicle frame and is also subject to braking torque and reaction force. The stiffness of the drive axle housing is crucial to the economy and safety of the entire vehicle.

[0003] To obtain the stiffness of the drive axle housing, the traditional method involves conducting bench stiffness tests. The drive axle housing is fixed on a bench, pressure is applied to simulate loads, and test data is collected using sensors and other equipment to calculate the stiffness. This method is time-consuming, labor-intensive, and inefficient. To improve the efficiency of stiffness calculation, finite element analysis (FEM) can be used to perform FEM analysis on the drive axle housing bench model, obtaining the stiffness value based on the simulation results. However, current FEM drive axle stiffness calculations do not consider the influence of bolt preload and lateral friction of the cylindrical rollers at the shaft end on the drive axle stiffness. This results in a deviation between the calculated and actual stiffness values, leading to inaccurate stiffness simulations and affecting the safety performance of the drive axle housing. Summary of the Invention

[0004] To address the aforementioned issues, this invention provides a method for simulating the stiffness of a commercial vehicle drive axle housing. During finite element analysis, a preload is applied to the bolts, and a lateral friction force is applied to the cylindrical roller at the axle head, thereby improving the accuracy of the finite element analysis.

[0005] In a first aspect, the technical solution of the present invention provides a method for simulating the stiffness of a commercial vehicle drive axle housing, comprising the following steps: Import the original model of the drive axle housing test bench into the finite element analysis software; The original model of the drive axle housing test bench is configured using finite element method to construct a finite element model of the drive axle housing test bench. This includes performing finite element processing on the original model of the drive axle housing test bench, applying preload to the bolts connecting the main reduction housing and the drive axle housing, and applying lateral friction force to the cylindrical roller at the shaft end of the drive axle housing. Finite element simulation calculations were performed on the finite element model of the drive axle housing test bench, and the stiffness value of the drive axle housing was output.

[0006] In an optional implementation, a preload is applied to the bolts connecting the main reduction housing and the drive axle housing, specifically including: Pre-measure the actual strain value of the bolts connecting the main reduction housing and the drive axle housing; Calculate the bolt preload based on the actual strain value; Apply the calculated preload to the corresponding bolt.

[0007] In an optional implementation, the actual strain value of the bolts connecting the main reduction gear housing and the drive axle housing is measured in advance, specifically including: Strain gauges are arranged on the studs of the bolt to be tested. The arrangement methods include 0° uniaxial strain gauge arrangement, uniaxial strain gauge arrangement with 180° intervals, and full bridge arrangement. Tighten the drive axle housing and main reduction housing with standard torque using a torque wrench, and read the strain value of the strain gauge using a data acquisition device; When the arrangement includes a 0° uniaxial strain gauge arrangement, the preload of the bolt to be tested is calculated using the following formula (1). :

[0008] (1)

[0009] Where E is the elastic modulus and S is the cross-sectional area of ​​the bolt. For the first The strain value of each bolt measured at the 0° position;

[0010] When the arrangement is a uniaxial strain gauge arrangement with 180° intervals, the preload of each bolt is calculated using the following formula (2). F 预 : (2)

[0011] in, For the first The strain value of each bolt measured at a 180° position;

[0012] When the arrangement is a full bridge arrangement, the preload of each bolt is calculated using the following formula (3). F 预 : (3)

[0013] in, For the first The strain value measured at the 90° position of each bolt. For the first The strain value measured at a 270° position for each bolt. It is Poisson's ratio.

[0014] In an optional implementation, a lateral frictional force is applied to the cylindrical roller at the drive axle housing shaft head, specifically including: The lateral friction force of the cylindrical roller at the axle head of the drive bridge housing is measured in advance at each target moment under each target load; The lateral friction force at each target moment under the corresponding target load is applied to the cylindrical roller at the shaft head of the drive axle housing.

[0015] In an optional implementation, the lateral frictional force of the cylindrical roller at the axle head of the drive bridge housing is measured in advance at each target time under each target load, specifically including: In the actual drive axle housing bench stiffness test, a target load is added to the drive axle housing; Calculate the shaft head pressure based on the target load. ;

[0016] Record the contact angle between the shaft head clamp and the cylindrical roller at the target time t. ;

[0017] The lateral friction force of the cylindrical roller at the drive axle housing shaft head at the target time t under the target load is calculated according to the following formula (4). :

[0018] (4).

[0019] In an optional implementation, the output drive axle housing stiffness value specifically includes: Output the displacement of the target position of the drive axle housing under the target load; The stiffness value of the drive axle housing under the target load is obtained by using the stiffness calculation formula based on the output displacement.

[0020] In an optional implementation, the original model of the drive axle housing bench is imported into the finite element analysis software, specifically including: Prepare the original model of the drive axle housing test bench; Convert the original model of the drive axle housing bench to STP format; Import the converted model into HyperMesh software.

[0021] In an optional implementation, the original model of the drive axle housing test bench is subjected to finite element analysis, specifically including: Geometric preprocessing and mesh generation were performed on the original model of the drive axle housing test bench.

[0022] In one optional implementation, mesh generation specifically includes: The shaft head is meshed using hexahedral elements, while all other parts are meshed using tetrahedral elements.

[0023] In an optional implementation, after outputting the drive axle housing stiffness value, the following steps are also included: The stiffness value of the drive axle obtained from the drive axle housing bench stiffness test is compared with the stiffness value output by the simulation under the same load and the same target position displacement. If the two are consistent, the finite element model of the drive axle housing is deemed qualified. If the two are inconsistent, adjust them.

[0024] This invention provides a method for simulating the stiffness of a commercial vehicle drive axle housing. Compared with existing technologies, this method offers the following advantages: After importing the drive axle housing bench model into finite element analysis software for finite element processing, a preload is applied to the bolts connecting the main reduction housing and the drive axle housing, and a lateral friction force is applied to the cylindrical rollers at the axle head of the drive axle housing. Based on this, finite element simulation calculations are performed, and the stiffness value of the drive axle housing is output. This invention improves the accuracy of finite element analysis by applying a preload to the bolts and a lateral friction force to the cylindrical rollers at the axle head, thus providing guidance for the forward development and structural optimization of drive axle housings. Attached Figure Description

[0025] To more clearly illustrate the technical solutions of the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of a simulation method for the stiffness of a commercial vehicle drive axle housing provided in an embodiment of the present invention.

[0027] Figure 2 This is a schematic diagram of the strain gauge arrangement in a full-bridge arrangement for bolt preload.

[0028] Figure 3 yes Figure 2 A schematic diagram of a strain gauge Wheatstone bridge with the arrangement shown.

[0029] Figure 4 This is a simplified mechanical analysis diagram of the drive axle housing stiffness bench test.

[0030] Figure 5 This is a schematic diagram showing the force analysis of the lateral frictional forces on cylindrical rollers A1 and A2. Detailed Implementation

[0031] To enable those skilled in the art to better understand the present invention, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are merely some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0033] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0034] Figure 1 This is a schematic diagram of a simulation method for the stiffness of a commercial vehicle drive axle housing provided in an embodiment of the present invention, as shown below. Figure 1 As shown, the method includes the following steps.

[0035] S1. Import the original model of the drive axle housing platform into the finite element analysis software.

[0036] Based on the simulation requirements, prepare the original model of the drive axle housing test bench. To adapt to finite element simulation, convert the original model of the drive axle housing test bench to STP format, and then import the converted model into finite element analysis software, such as HyperMesh software.

[0037] It should be noted that after importing the finite element analysis software, in order to ensure the accuracy of the model, the model is checked against the actual vehicle's drive axle, including the axle head size, weld position, connection relationship, and whether there are any material defects. If there are any inconsistencies, the corresponding positions are modified first.

[0038] S2, construct the finite element model of the drive axle housing test bench by performing finite element configuration on the original model of the drive axle housing test bench.

[0039] The finite element configuration of this embodiment includes performing finite element processing on the original model of the drive axle housing test bench, applying preload to the connecting bolts of the main reduction housing and the drive axle housing, and applying lateral friction force to the cylindrical roller at the shaft end of the drive axle housing.

[0040] S2.1, perform finite element analysis on the original model of the drive axle housing test bench.

[0041] The finite element processing in this embodiment includes geometric preprocessing and mesh generation of the original model of the drive axle housing test bench.

[0042] When performing mesh generation, the shaft head is meshed using hexahedral elements, while other parts, such as other parts of the drive axle, leaf spring seat, flange, main reduction housing, and rear cover, are meshed using tetrahedral elements.

[0043] In practice, connections are established according to the correct connection relationships between components, and the mesh is densified at the locations of interest.

[0044] S2.2, apply preload to the bolts connecting the main reduction gear housing and the drive axle housing.

[0045] The drive axle housing and the main reduction gear housing are connected by several bolts, and the accuracy of the bolt preload affects the stiffness accuracy of the axle housing. Considering the influence of the preload of the bolts connecting the main reduction gear housing and the drive axle housing on the stiffness of the drive axle housing, a preload is applied to the bolts connecting the main reduction gear housing and the drive axle housing during finite element simulation, that is, a preload constraint is added to the bolts of the model.

[0046] In this embodiment, the actual preload of the bolts is calculated in advance and then applied to the bolts. To obtain the actual preload of the bolts, this embodiment measures the actual strain value of the bolts connecting the main reduction housing and the drive axle housing in advance, calculates the preload of the bolts based on the actual strain value, and then applies the calculated preload to the corresponding bolts in the finite element analysis software.

[0047] This embodiment measures the preload of a bolt by placing strain gauges on the bolt stud, specifically including the following steps.

[0048] Step 1: Install strain gauges on each bolt to be tested.

[0049] Different arrangement methods can eliminate the influence of bending on the preload. The arrangement methods in this embodiment include 0° uniaxial strain gauge arrangement, uniaxial strain gauge arrangement with 180° intervals, and full bridge arrangement.

[0050] Figure 2 This is a schematic diagram showing the strain gauge arrangement for a full-bridge configuration with bolt preload. Figure 3 for Figure 2 A schematic diagram of a strain gauge Wheatstone bridge with the arrangement shown.

[0051] Step 2: Tighten the drive axle housing and main reduction housing with standard torque using a torque wrench, and read the strain value of the strain gauge using a data acquisition device.

[0052] Standard bolts correspond to standard torque. The standard torque is set using a torque wrench, and the main reduction housing and drive axle housing are tightened to the standard torque. The strain gauge values ​​are then read using a data acquisition device.

[0053] When the arrangement includes a 0° uniaxial strain gauge arrangement, the preload of the bolt to be tested is calculated using the following formula (1). :

[0054] (1)

[0055] Where E is the elastic modulus and S is the cross-sectional area of ​​the bolt. For the first The strain value of each bolt measured at the 0° position;

[0056] When the arrangement is a uniaxial strain gauge arrangement with 180° intervals, the preload of each bolt is calculated using the following formula (2). F 预 : (2)

[0057] in, For the first The strain value of each bolt measured at a 180° position;

[0058] When the arrangement is a full bridge arrangement, the preload of each bolt is calculated using the following formula (3). F 预 : (3)

[0059] in, For the first The strain value measured at the 90° position of each bolt. For the first The strain value measured at a 270° position for each bolt. It is Poisson's ratio.

[0060] S2.3 applies lateral friction force to the cylindrical roller at the axle head of the drive axle housing.

[0061] Figure 4 This is a simplified mechanical analysis diagram of the drive axle housing stiffness bench test. The upper end of the drive axle housing is connected to the leaf spring seat of the drive axle housing by a clamp D through two cylindrical rollers C1 and C2. The drive axle shaft end is in contact with the bench by two clamps B1 and B2 through cylindrical rollers A1 and A2 respectively. A hydraulic cylinder applies pressure F to clamp D. 缸 .

[0062] As can be seen from the connection method of the drive axle housing test bench, the drive axle housing shaft head clamp contacts the test bench through the cylindrical rod. There is a relative rotation between the clamp and the rod. At this time, there is a lateral force between the cylindrical rod and the test bench, and the magnitude of the lateral force is related to the smoothness of the test bench and whether there is lubricant. Figure 5 This is a schematic diagram showing the force analysis of the lateral frictional forces on cylindrical rollers A1 and A2.

[0063] This embodiment pre-measures the lateral friction force of the cylindrical roller at the axle head of the drive axle housing at each target time under various target loads. Then, during simulation, the lateral friction force at each target time under the corresponding target load is applied to the cylindrical roller at the axle head of the drive axle housing. Specifically, it includes the following steps.

[0064] Step 1: In the actual drive axle housing bench stiffness test, add the target load to the drive axle housing.

[0065] Step 2: Calculate the shaft head pressure based on the target load. .

[0066] For example, if the target load is 12 tons, the axle head pressure is 2.5 times the target load. Of course, the axle head pressure is calculated according to the corresponding multiple based on the actual requirements, which will not be elaborated here.

[0067] Step 3: Record the contact angle between the shaft head clamp and the cylindrical roller at the target time t. .

[0068] Step 4: Calculate the lateral friction force of the cylindrical roller at the drive axle housing shaft head at the target time t under the target load according to the following formula (4). ：

[0069] (4).

[0070] It should be noted that the friction force during roller movement f Must meet This refers to the lateral force of the roller.

[0071] S3 performs finite element simulation calculations on the finite element model of the drive axle housing test bench and outputs the stiffness value of the drive axle housing.

[0072] Simulation calculations were performed on a virtual bench drive axle housing model that considered the measured bolt preload applied to the main reduction housing and drive axle housing, as well as the lateral friction applied between the cylindrical rod and the test bench. The displacement of the target position (such as the bottom of the center position) of the drive axle housing under each load was output, and the stiffness value under each load was obtained through the stiffness calculation formula.

[0073] S4. Compare the stiffness value of the drive axle obtained from the drive axle housing bench stiffness test with the stiffness value output by the simulation under the same load and at the same target position displacement.

[0074] S5. If the two are consistent, the finite element model of the drive axle housing is deemed qualified.

[0075] S6. If the two are inconsistent, adjust the applied bolt preload and the lateral friction force of the cylindrical roller.

[0076] In practice, to ensure simulation accuracy, stiffness tests were conducted on the drive axle housing according to the bench test loading specifications, and the stiffness values ​​of the drive axle housing under various loads were obtained. The stiffness values ​​obtained from the bench test were compared with the stiffness values ​​of the simulated axle housing under the same load and at the same location. If the results showed good consistency, a high-precision virtual bench drive axle housing stiffness model was obtained. If there were inconsistencies, the applied bolt preload and the lateral friction force of the cylindrical rollers were adjusted, and the simulation was repeated.

[0077] After obtaining the finite element model of the drive axle housing test bench that meets the simulation accuracy requirements, the stiffness simulation of the subsequent drive axle housing is performed based on its finite element configuration results, thereby improving the efficiency of stiffness calculation.

[0078] The above-disclosed embodiments are merely preferred embodiments of the present invention, but the present invention is not limited thereto. Any non-creative variations that can be conceived by those skilled in the art, as well as any improvements and modifications made without departing from the principles of the present invention, should fall within the protection scope of the present invention.

Claims

1. A method of commercial vehicle drive axle housing stiffness simulation, characterized by, Includes the following steps: Import the original model of the drive axle housing test bench into the finite element analysis software; The original model of the drive axle housing test bench is configured using finite element method to construct a finite element model of the drive axle housing test bench. This includes performing finite element processing on the original model of the drive axle housing test bench, applying preload to the bolts connecting the main reduction housing and the drive axle housing, and applying lateral friction force to the cylindrical roller at the shaft end of the drive axle housing. Finite element simulation calculations were performed on the finite element model of the drive axle housing test bench, and the stiffness value of the drive axle housing was output.

2. The method for simulating the stiffness of a commercial vehicle drive axle housing according to claim 1, characterized in that, Apply preload to the bolts connecting the main reduction gear housing and the drive axle housing, specifically including: Pre-measure the actual strain value of the bolts connecting the main reduction housing and the drive axle housing; Calculate the bolt preload based on the actual strain value; Apply the calculated preload to the corresponding bolt.

3. The method for simulating the stiffness of a commercial vehicle drive axle housing according to claim 2, characterized in that, Pre-measure the actual strain value of the connecting bolts between the main reduction gear housing and the drive axle housing, specifically including: Strain gauges are arranged on the studs of the bolt to be tested. The arrangement methods include 0° uniaxial strain gauge arrangement, uniaxial strain gauge arrangement with 180° intervals, and full bridge arrangement. Tighten the drive axle housing and main reduction housing with standard torque using a torque wrench, and read the strain value of the strain gauge using a data acquisition device; When the arrangement includes a 0° uniaxial strain gauge arrangement, the preload of the bolt to be tested is calculated using the following formula (1). : （1） Where E is the elastic modulus and S is the cross-sectional area of ​​the bolt. For the first The strain value of each bolt measured at the 0° position; When the arrangement is a uniaxial strain gauge arrangement with 180° intervals, The preload of each bolt is calculated using the following formula (2). F 预 : （2） in, For the first The strain values ​​of each bolt measured at a 180° position; When the arrangement is a full bridge arrangement, the preload of each bolt is calculated using the following formula (3). F 预 : （3） in, For the first The strain value measured at the 90° position of each bolt. For the first The strain value measured at a 270° position for each bolt. It is Poisson's ratio.

4. The method for simulating the stiffness of a commercial vehicle drive axle housing according to claim 1, 2, or 3, characterized in that, Applying lateral frictional force to the cylindrical roller at the axle head of the drive axle housing specifically includes: The lateral friction force of the cylindrical roller at the axle head of the drive bridge housing is measured in advance at each target moment under each target load; The lateral friction force at each target moment under the corresponding target load is applied to the cylindrical roller at the shaft head of the drive axle housing.

5. The method for simulating the stiffness of a commercial vehicle drive axle housing according to claim 4, characterized in that, The lateral frictional force of the cylindrical roller at the axle head of the drive bridge housing is measured in advance at each target moment under each target load, specifically including: In the actual drive axle housing bench stiffness test, a target load is added to the drive axle housing; Calculate the shaft head pressure based on the target load. ; Record the contact angle between the shaft head clamp and the cylindrical roller at the target time t. ; The lateral friction force of the cylindrical roller at the drive axle housing shaft head at the target time t under the target load is calculated according to the following formula (4). ： （4）。 6. The method for simulating the stiffness of a commercial vehicle drive axle housing according to claim 5, characterized in that, The output drive axle housing stiffness values ​​specifically include: Output the displacement of the target position of the drive axle housing under the target load; The stiffness value of the drive axle housing under the target load is obtained by using the stiffness calculation formula based on the output displacement.

7. The method for simulating the stiffness of a commercial vehicle drive axle housing according to claim 6, characterized in that, Importing the original model of the drive axle housing test bench into the finite element analysis software specifically includes: Prepare the original model of the drive axle housing test bench; Convert the original model of the drive axle housing bench to STP format; Import the converted model into HyperMesh software.

8. The method for simulating the stiffness of a commercial vehicle drive axle housing according to claim 7, characterized in that, Finite element analysis was performed on the original model of the drive axle housing test bench, specifically including: Geometric preprocessing and mesh generation were performed on the original model of the drive axle housing test bench.

9. The method for simulating the stiffness of a commercial vehicle drive axle housing according to claim 8, characterized in that, Mesh generation specifically includes: The shaft head is meshed using hexahedral elements, while all other parts are meshed using tetrahedral elements.

10. The method for simulating the stiffness of a commercial vehicle drive axle housing according to claim 9, characterized in that, After outputting the drive axle housing stiffness value, the following steps are also included: The stiffness value of the drive axle obtained from the drive axle housing bench stiffness test is compared with the stiffness value output by the simulation under the same load and the same target position displacement. If the two are consistent, the finite element model of the drive axle housing is deemed qualified. If the two are inconsistent, adjust the applied bolt preload and the lateral friction force of the cylindrical roller.

Images