A method for determining the transmission load for reliability analysis

Abstract

The present invention discloses a method for determining the transmission load for reliability analysis, which relates to the technical field of transmissions. This method designs driving conditions and shifting rules, inputs the driving conditions, shifting rules, and vehicle data into a visual simulation tool for simulation calculation, and screens the data from the simulation calculation to combine the target gears. Finally, the transmission load distribution of the target gears is obtained through simulation again using the visual simulation tool, including the S1 simulation data design step, the S2 simulation data calculation and screening step, and the S3 simulation calculation of the transmission load step. The present invention establishes a dynamic model to perform simulation motion through the Simulink simulation tool, combines engine parameters to screen out the target gears and combines them, and then obtains the transmission load distribution result of the target gears through simulation again using the Simulink simulation tool. Through this method, the transmission load distribution of different target gear combinations under multi-condition operation can be analyzed.

Description

Technical Field

[0001] The present invention relates to the technical field of gearboxes, and specifically to a method for determining loads of a gearbox using Simulink simulation analysis. Background Art

[0002] A gearbox, also known as a transmission, is a transmission component used to change the speed and torque from the engine and can fix or shift gears to change the transmission ratio between the output shaft and the input shaft. The loads on the current gearbox have a crucial impact on the reliability of the whole vehicle. Under the shifting laws such as power performance and economy, the gears in which the whole vehicle is located can well ensure the reliability of the whole vehicle.

[0003] However, in the prior art, there are multiple different allowable gears in different speed ranges, and many gears are not under conditions such as power performance and economy. Currently, the loads of the gearboxes for the reliability of most whole vehicles are obtained under shifting laws such as power performance and economy, and the gearbox loads not obtained under conditions such as power performance and economy are not fully analyzed for the reliability of the whole vehicle, resulting in no reliable data for reference in the subsequent development of the gearbox. Summary of the Invention

[0004] The purpose of the present invention is to provide a method for determining gearbox loads for reliability analysis to solve the problems in the above background art.

[0005] To achieve the above purpose, the present invention provides the following technical solution: A method for determining gearbox loads for reliability analysis, which is based on existing visualization simulation tools. By designing driving conditions and shifting laws, the driving conditions, shifting laws, and vehicle data are input into the visualization simulation tool for simulation calculation, and the data of the simulation calculation are screened to combine the target gears. Finally, the gearbox load distribution of the target gears is obtained through simulation again by the visualization simulation tool; it includes S1 simulation data design step, S2 simulation data calculation and screening step, and S3 simulation calculation of gearbox loads step; specifically as follows:

[0006] The S1 simulation data design step includes S11 driving condition setting step, S12 gear shifting law setting step, and S13 dynamic model establishment step; specifically as follows:

[0007] The S11 driving condition setting step, according to the driving data of the vehicle, obtains the working condition diagram of the driving mode under different working conditions by programming.

[0008] The S12 gear shifting law setting step, sets the power shifting law and the economic shifting law.

[0009] Among them, the shifting speeds of the power shifting law and the economic shifting law are obtained as follows:

[0010] For the power shifting law, the vehicle speed corresponding to the intersection point of the accelerations of adjacent gears is used as the shifting point.

[0011] For the economic shifting law, the vehicle speed corresponding to the minimum fuel consumption of adjacent gears is used as the shifting point.

[0012] Step S13 of establishing the dynamic model: Input the driving mode working condition diagram obtained in S11 and the shifting law obtained in S12 into the visualization simulation tool, and incorporate the basic vehicle data to form a complete vehicle dynamic model.

[0013] The simulation data calculation and screening steps in S2 include the simulation data accuracy detection step S21, the simulation output steps of the power simulation speed and the economic simulation speed S22, the allowable gear steps at different vehicle speeds S23, and the screening target gear steps S24; specifically as follows:

[0014] In the simulation data accuracy detection step S21, set the simulation basic sampling time of the visualization simulation tool, and perform simulation calculations on the complete vehicle dynamic model established in S13 through the visualization simulation tool. If the simulation accuracy requirements are met, proceed to the next step; otherwise, return to S13 to debug the model.

[0015] In the simulation output steps of the power simulation speed and the economic simulation speed S22, after the simulation calculations in S21 meet the requirements, perform the simulations of the power simulation speed and the economic simulation speed to obtain the gear position diagrams in different speed intervals.

[0016] In the allowable gear steps at different vehicle speeds S23, calculate the allowable gears at different speeds according to the engine parameters.

[0017] In the screening target gear steps S24, screen out the target gears in different speed intervals by programming the gear position diagrams in different speed intervals obtained from the power simulation speed and the economic simulation speed in S22 and the allowable gears at different speeds calculated in S23.

[0018] Among them, for each speed interval, the left boundary of the target gear is the gear obtained from the power simulation minus 1 gear, and the right boundary of the target gear is the gear obtained from the economic simulation plus 1 gear, so as to obtain all the gears considered in each speed interval.

[0019] The simulation calculation of the transmission load in S3 includes the target gear combination step S31 and the simulation movement step of the target gear combination S32; specifically as follows:

[0020] In the target gear combination step S31, combine the target gears in different speed intervals screened out in step S24.

[0021] Among them, the way of combining target gear positions is as follows: the gear positions within a certain speed range are freely combined, and then the gear positions in all different speed ranges are combined to obtain the gear position distribution under the complete driving conditions.

[0022] S32 The simulation movement steps of the target gear position combination. The target gear position combination in S31 is subjected to simulation movement through a visualization simulation tool to obtain the transmission load distribution result of the target gear position.

[0023] Preferably, the driving conditions include one or more of a fully loaded flat road driving condition, a fully loaded climbing condition, an unloaded flat road driving condition, and / or an unloaded downhill condition.

[0024] Preferably, the driving data of the vehicle includes driving distance, slope, vehicle speed, and vehicle mass.

[0025] Preferably, the incorporated basic vehicle data includes one or more of mass, rolling resistance coefficient, air resistance coefficient, stiffness coefficients of each transmission component, damping coefficients of each transmission component, and / or moment of inertia of each transmission component.

[0026] Preferably, the simulation basic sampling time is 0.001 s.

[0027] Preferably, the returned model is debugged for one or more of the parameter values of each transmission component, checking the connection relationship of the modules, and / or checking the constraint conditions.

[0028] Preferably, the engine parameters based on which the allowable gear positions at different speeds are calculated include speed range, transmission ratio of the gearbox, transmission ratio of the final drive, and wheel radius.

[0029] Preferably, the way of combining the target gear positions is the tree classification method.

[0030] Preferably, the condition for combining the target gear positions is no gear skipping.

[0031] Preferably, the visualization simulation tool adopted is the Simulink simulation tool.

[0032] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0033] The present invention establishes a dynamic model for the driving conditions, gear shifting laws, and basic vehicle data involved, conducts simulation movements through the Simulink simulation tool, and combines engine parameters to screen out target gears. After combination, the Simulink simulation tool is used again to simulate and obtain the transmission load distribution results of the target gears. Through this method, the transmission load distribution of different target gear combinations under multi-condition operation can be analyzed, providing research ideas for the subsequent reliability analysis of the gearbox and ensuring the safe and stable operation of the whole vehicle. Brief Description of the Drawings

[0034] Figure 1 It is a flowchart of a method for determining the transmission load for reliability analysis according to the present invention;

[0035] Figure 2 It is a schematic diagram for screening target gears in different speed ranges in a method for determining the transmission load for reliability analysis according to the present invention;

[0036] Figure 3 It is a schematic diagram of target gear combinations in a method for determining the transmission load for reliability analysis according to the present invention. Detailed Embodiments

[0037] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0038] Embodiment

[0039] Please refer to Figures 1 - 3 , a method for determining the transmission load for reliability analysis. Based on the Simulink simulation tool, by designing the driving conditions and shifting laws, the driving conditions, shifting laws, and vehicle data are input into the Simulink simulation tool for simulation calculation, and the simulation calculation data is screened to combine the target gears. Finally, the Simulink simulation tool is used again to simulate and obtain the transmission load distribution of the target gears; the analysis of the load distribution is completed through step S1 of simulating data design, step S2 of calculating and screening simulating data, and step S3 of simulating the transmission load; specifically, the steps are as follows:

[0040] Step S1 of simulating data design completes the setting of the simulating data model through step S11 of setting driving conditions, step S12 of setting gear shifting laws, and step S13 of establishing a dynamic model; specifically, as follows:

[0041] S11 Driving condition setting step: Obtain the working condition diagrams of driving modes under full-load flat road driving condition, full-load climbing condition, no-load flat road driving condition, and no-load downhill condition by programming based on the driving distance, slope, vehicle speed, and vehicle mass of the vehicle's driving data;

[0042] S12 Gear shifting law setting step: Set the power shifting law and the economic shifting law;

[0043] Among them, the method for obtaining the shifting vehicle speeds of the power shifting law and the economic shifting law is as follows:

[0044] The power shifting law uses the vehicle speed corresponding to the intersection of accelerations of adjacent gears as the shifting point;

[0045] The power shifting law setting formula is as follows:

[0046]

[0047] Among them, is the acceleration of two adjacent gears; F tn 、F tn+1 are the driving forces of two adjacent gears; F f 、F w are the rolling resistance and air resistance respectively; δ n 、δ n+1 are the rotating mass conversion coefficients of two adjacent gears.

[0048] The economic shifting law uses the vehicle speed corresponding to the minimum fuel consumption of adjacent gears as the shifting point;

[0049] The economic shifting law setting formula is as follows:

[0050]

[0051] Among them, is the fuel consumption of two adjacent gears; F tn 、F tn+1 are the driving forces of two adjacent gears; F f 、F w 、F i are the rolling resistance, air resistance, and gradient resistance respectively; δ n 、δ n+1 are the rotating mass conversion coefficients of two adjacent gears.

[0052] S13 Establishing a dynamic model step: Input the driving mode working condition diagram obtained in S11 and the shifting law obtained in S12 into the Simulink simulation tool, and incorporate the basic data of vehicle mass, rolling resistance coefficient, air resistance coefficient, stiffness coefficients of each transmission component, damping coefficients of each transmission component, and moment of inertia of each transmission component to form a vehicle dynamic model;

[0053] The S2 simulation data calculation and screening steps include the S21 simulation data accuracy detection step, the S22 dynamic simulation speed and economic simulation speed simulation output step, the S23 allowable gear position at different vehicle speeds step, and the S24 screening target gear position step; specifically as follows:

[0054] In the S21 simulation data accuracy detection step, set the simulation basic sampling time of the Simulink simulation tool to 0.001 s, and perform simulation calculations on the vehicle dynamics model established in S13 through the Simulink simulation tool. If the simulation accuracy requirements are met, proceed to the next step; otherwise, return to S13 to debug the parameter values of each transmission component, check the module connection relationship, and check the constraint conditions of the model.

[0055] In the S22 dynamic simulation speed and economic simulation speed simulation output step, after the simulation calculations in S21 meet the requirements, perform simulations on the dynamic simulation speed and economic simulation speed to obtain the gear position diagrams in different speed intervals.

[0056] In the S23 allowable gear position at different vehicle speeds step, calculate the allowable gear positions at different speeds based on the engine speed range, transmission ratio, final drive ratio, and wheel radius parameters.

[0057] As Figure 2 shown, in the S24 screening target gear position step, screen out the target gear positions in different speed intervals from the gear position diagrams in different speed intervals of the dynamic simulation speed and economic simulation speed obtained in S22 and the allowable gear positions at different speeds calculated in S23 through programming;

[0058] Among them, for each speed interval, the left boundary of the target gear position is the gear position obtained from the dynamic simulation minus 1 gear, and the right boundary of the target gear position is the gear position obtained from the economic simulation plus 1 gear, to obtain all the gears considered in each speed interval;

[0059] The S3 simulation calculation of the transmission load steps includes the S31 target gear position combination step and the S32 simulation movement step of the target gear position combination; specifically as follows:

[0060] In the S31 target gear position combination step, combine the target gear positions in different speed intervals screened out in step S24 through the tree classification method, and the combination condition is no gear skipping;

[0061] As Figure 3 shown, the way of combining the target gear positions is: freely combine the gears in a certain speed interval and then combine the gears in all different speed intervals to obtain the gear position distribution under the complete driving conditions;

[0062] S32 Simulation motion steps for the target gear combination. Simulate the target gear combination in S31 using the Simulink simulation tool to obtain the gearbox load distribution results for the target gear.

[0063] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A method for determining the transmission load for reliability analysis, characterized in that, This method is based on existing visualization simulation tools. By designing driving conditions and shifting rules, the driving conditions, shifting rules, and vehicle data are input into the visualization simulation tool for simulation calculation. Then, the data from the simulation calculation is screened to combine the target gears. Finally, the visualization simulation tool is used again for simulation to obtain the transmission load distribution of the target gears. It includes step S1 for designing simulation data, step S2 for calculating and screening simulation data, and step S3 for simulating the transmission load. The specific steps are as follows: Step S1 for designing simulation data includes step S11 for setting driving conditions, step S12 for setting gear shifting rules, and step S13 for establishing a dynamic model. The details are as follows: Step S11 for setting driving conditions: Using programming, obtain the working condition diagram of the driving mode under different working conditions based on the driving data of the vehicle. Step S12 for setting gear shifting rules: Set the power-based shifting rule and the economy-based shifting rule. Among them, the method for obtaining the shifting speeds of the power-based shifting rule and the economy-based shifting rule is as follows: For the power-based shifting rule, use the vehicle speed corresponding to the intersection of accelerations of adjacent gears as the shifting point. For the economy-based shifting rule, use the vehicle speed corresponding to the minimum fuel consumption of adjacent gears as the shifting point. Step S13 for establishing a dynamic model: Input the driving mode working condition diagram obtained in S11 and the shifting rules obtained in S12 into the visualization simulation tool, and incorporate the basic vehicle data to form a vehicle dynamic model. Step S2 for calculating and screening simulation data includes step S21 for detecting the accuracy of simulation data, step S22 for simulating and outputting the power-based simulation speed and the economy-based simulation speed, step S23 for determining the allowable gears at different vehicle speeds, and step S24 for screening the target gears. The details are as follows: Step S21 for detecting the accuracy of simulation data: Set the basic sampling time of the simulation in the visualization simulation tool. Use the visualization simulation tool to perform simulation calculation on the vehicle dynamic model established in S13. If the simulation accuracy requirements are met, proceed to the next step; otherwise, return to S13 to debug the model. For the returned model, perform debugging on the parameter values of each transmission component, check the connection relationship of the modules, and / or check the constraint conditions. Step S22 for simulating and outputting the power-based simulation speed and the economy-based simulation speed: After the simulation calculation in S21 meets the requirements, perform simulations on the power-based simulation speed and the economy-based simulation speed to obtain the gear position diagrams in different speed intervals. Step S23 for determining the allowable gears at different vehicle speeds: Calculate the allowable gears at different vehicle speeds based on the engine parameters. Step S24 for screening the target gears: Use programming to screen out the target gears in different speed intervals from the gear position diagrams in different speed intervals of the power-based simulation speed and the economy-based simulation speed obtained in S22 and the allowable gears at different vehicle speeds calculated in S23. Among them, for each speed interval, the left boundary of the target gear is the gear obtained from the power-based simulation minus 1 gear, and the right boundary of the target gear is the gear obtained from the economy-based simulation plus 1 gear, to obtain all the gears considered in each speed interval. Step S3 for simulating the transmission load includes step S31 for combining the target gears and step S32 for the simulation movement of the combined target gears. The details are as follows: S31 Target gear combination step, combining the target gears in different speed ranges selected in step S24; Among them, the way of target gear combination is: freely combining the gears within a certain speed range and then combining the gears in all different speed ranges to obtain the gear distribution under the complete driving conditions; S32 Simulation motion step of target gear combination, performing simulation motion on the target gear combination in S31 through a visualization simulation tool to obtain the gearbox load distribution result of the target gear.

2. The method for determining the transmission load for reliability analysis according to claim 1, characterized in that: The driving conditions include one or more of full-load flat-road driving conditions, full-load climbing conditions, no-load flat-road driving conditions, and no-load downhill conditions.

3. The method for determining the transmission load for reliability analysis according to claim 2, characterized in that: The driving data of the vehicle include driving distance, slope, vehicle speed, and vehicle mass.

4. The method for determining the transmission load for reliability analysis according to claim 3, characterized in that: The incorporated basic vehicle data include one or more of mass, rolling resistance coefficient, air resistance coefficient, stiffness coefficients of each transmission component, damping coefficients of each transmission component, and moments of inertia of each transmission component.

5. The method for determining the transmission load for reliability analysis according to claim 1, characterized in that: The simulation basic sampling time is 0.001 s.

6. The method for determining the transmission load for reliability analysis according to claim 1, characterized in that: The engine parameters based on which the allowable gears at different speeds are calculated include the speed range, transmission ratio of the gearbox, transmission ratio of the final drive, and wheel radius.

7. The method for determining the transmission load for reliability analysis according to claim 1, characterized in that: The way of combining the target gears is the tree classification method.

8. The method for determining the transmission load for reliability analysis according to claim 7, characterized in that: The condition for combining the target gears is no gear skipping.

9. The method for determining the transmission load for reliability analysis according to any one of claims 1-8, characterized in that:The visualization simulation tool used is the Simulink simulation tool.

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