A method and device for designing a stiffness curve of a powertrain suspension system

Abstract

This invention discloses a method and apparatus for designing the stiffness curve of a powertrain mounting system. The design method includes: acquiring vehicle state parameters and stiffness curve data for each mounting; establishing a dynamic model of the powertrain mounting system based on the vehicle state parameters and stiffness curve data, and determining the vibration data for each mounting; comparing the nonlinear stiffness curve data and vibration data of each mounting with preset data conditions, and correcting the stiffness curve data based on the comparison results to obtain a corrected dynamic model; wherein the stiffness curve data includes nonlinear stiffness curve data; and determining the first limit dimension of the mounting based on the comparison results, according to the vehicle state parameters and preset limit rules. The technical solution of this invention, combined with the design of stiffness curve data under actual vehicle conditions, improves the reliability of noise and vibration transmission reduction in mountings, and effectively improves vehicle ride comfort.

Description

Technical Field

[0001] The present invention relates to the field of vehicle vibration and noise control technology, and in particular to a method and apparatus for designing the stiffness curve of a powertrain mounting system. Background Technology

[0002] In vehicle NVH (Noise, Vibration, and Harshness) performance, the powertrain mounting system plays an increasingly important role. The powertrain mounting system supports the weight of the powertrain and reduces the bidirectional transmission of vibration between the engine assembly and the chassis, achieving vibration isolation and noise reduction.

[0003] To optimize the design and selection of powertrain mounting systems, the impact of various loads on the powertrain mounting system should be fully considered. However, traditional powertrain mounting system matching analysis methods only consider the impact of dynamic loads caused by random engine vibrations on the powertrain mounting system. This results in significant errors in the existing powertrain mounting system analysis and matching, affecting vehicle ride comfort. Summary of the Invention

[0004] This invention provides a method and apparatus for designing the stiffness curve of a powertrain mounting system, thereby improving the accuracy of analyzing and matching the stiffness curve of the powertrain mounting system and effectively improving the ride comfort of the vehicle.

[0005] According to one aspect of the present invention, a method for designing the stiffness curve of a powertrain mounting system is provided. The method is applied to a powertrain mounting system comprising multiple mounts, each mount including a housing and a limiting component. The housing includes a cavity, and the limiting component is retractably disposed within the cavity. The design method includes:

[0006] Obtain vehicle status parameters and stiffness curve data for each suspension mount;

[0007] Based on the vehicle state parameters and the stiffness curve data, a dynamic model of the powertrain mounting system is established, and the vibration data of each mounting is determined.

[0008] The nonlinear stiffness curve data and vibration data of each suspension are compared with preset data conditions, and the stiffness curve data are corrected according to the comparison results to obtain a dynamic correction model; wherein, the stiffness curve data includes nonlinear stiffness curve data.

[0009] Based on the comparison results, the first limiting dimension of the suspension is determined according to the vehicle state parameters and the preset limiting rules; wherein, the first limiting dimension includes the distance between the limiting component and the housing when no deformation occurs.

[0010] Optionally, the vehicle status parameters include vehicle operating data and powertrain parameters;

[0011] Before establishing the dynamic model of the powertrain mounting system based on the vehicle state parameters and the stiffness curve data, and determining the vibration data of each mounting, the method further includes:

[0012] Based on the vehicle state parameters, calculate the gearbox gear used within the preset test duration and the corresponding gearbox output torque;

[0013] Based on the actual usage time of each gear, determine the utilization rate of each gear and the utilization rate of the output torque of each gear.

[0014] Optionally, determining the first limiting dimension of the suspension based on the comparison result, according to the vehicle state parameters and preset limiting rules, includes:

[0015] When the nonlinear stiffness curve data of the suspension meets the preset data conditions, according to the vehicle operation data and the preset limit rules, the gearbox gear position when the second limit dimension reaches the limit dimension threshold and the probability of the second limit dimension reaching the limit dimension threshold are statistically analyzed; wherein, the second limit dimension includes the distance between the limit component and the housing when deformation occurs;

[0016] The first limit size of the suspension is determined based on the gearbox gear position when the second limit size reaches the limit size threshold and the probability that the second limit size reaches the limit size threshold.

[0017] Optionally, the vehicle state parameters include powertrain parameters;

[0018] The step of establishing a dynamic model of the powertrain mounting system based on the vehicle state parameters and the stiffness curve data, and determining the vibration data of each mounting, includes:

[0019] Based on the powertrain parameters and the stiffness curve data of each suspension, the triaxial force data of each suspension are determined, and the dynamic model is established.

[0020] Based on the aforementioned dynamic model, a preset torque is applied to the output shaft of the gearbox to determine the vibration data of each of the aforementioned suspensions.

[0021] Optionally, the vibration data includes attribute parameters and data on the functional relationship between force and compression.

[0022] The step of applying a preset torque to the output shaft of the gearbox based on the dynamic model and determining the vibration data of each of the aforementioned mounts includes:

[0023] When the applied preset torque is 0, determine the attribute parameters of each of the suspensions;

[0024] When the applied preset torque is within a preset range, the functional relationship data between the force and the compression amount is determined.

[0025] Optionally, the vehicle status parameters include powertrain parameters, which include engine idle speed and number of cylinders;

[0026] The step of comparing the nonlinear stiffness curve data of each of the suspensions with preset data conditions, and correcting the stiffness curve data according to the comparison results, includes:

[0027] The vibration isolation rate of each mount is determined based on the idle speed and the number of cylinders of the engine.

[0028] The vibration isolation rate is compared with the vibration isolation rate threshold to generate a first comparison result;

[0029] Based on the first comparison result, the nonlinear stiffness curve data is adjusted to meet the preset data conditions; wherein, the preset data conditions include the vibration isolation rate being greater than or equal to the vibration isolation rate threshold.

[0030] Optionally, the vibration data includes data on the functional relationship between force and compression.

[0031] The step of comparing the nonlinear stiffness curve data of each of the suspensions with preset data conditions and correcting the stiffness curve data based on the comparison results further includes:

[0032] Based on the functional relationship data between the force and the compression of each suspension, the static compression of each suspension is determined;

[0033] The static compression amount is compared with the compression amount threshold to generate a second comparison result;

[0034] Based on the second comparison result, the nonlinear stiffness curve data is adjusted to meet the preset data conditions; wherein, the preset data conditions include the static compression amount being less than or equal to the compression amount threshold.

[0035] Optionally, the stiffness curve data may further include linear stiffness curve data;

[0036] The step of comparing the nonlinear stiffness curve data of each of the suspensions with preset data conditions and correcting the stiffness curve data based on the comparison results further includes:

[0037] Based on the functional relationship data of the force and compression of each of the aforementioned suspensions, the stiffness curve data corresponding to the gearbox gear is compared with the preset stiffness curve data to generate a third comparison result;

[0038] Based on the third comparison result, the inflection point position between the linear stiffness curve data and the nonlinear stiffness curve data is adjusted to meet the preset data conditions; wherein, the inflection point position includes at least a first inflection point position and a second inflection point position.

[0039] Optionally, adjusting the inflection point position between the linear stiffness curve data and the nonlinear stiffness curve data based on the third comparison result to satisfy the preset data conditions includes:

[0040] When the high gear of the transmission corresponds to the nonlinear stiffness curve data, the position of the first inflection point is determined to satisfy the preset data conditions; wherein, the preset data conditions include that the high gear of the transmission and the linear stiffness curve data have a target mapping relationship;

[0041] When the low gear of the transmission corresponds to the linear stiffness curve data, the position of the second inflection point is determined to satisfy the preset data conditions; wherein, the preset data conditions include that the low gear of the transmission and the nonlinear stiffness curve data have a target mapping relationship.

[0042] According to another aspect of the present invention, a stiffness curve design apparatus for a powertrain mounting system is provided, the apparatus comprising:

[0043] The data acquisition module is used to acquire vehicle state parameters and stiffness curves of each suspension mount;

[0044] The model building module is used to build a dynamic model of the powertrain mounting system based on the vehicle state parameters and the stiffness curve data, and to determine the vibration data of each mounting.

[0045] The result comparison and correction module is used to compare the nonlinear stiffness curve data of each suspension with preset data conditions, and correct the stiffness curve data according to the comparison results to obtain a dynamic correction model; wherein, the stiffness curve data includes nonlinear stiffness curve data.

[0046] The limit size design module is used to determine the first limit size of the suspension based on the comparison results, the vehicle state parameters, and the preset limit rules; wherein, the first limit size includes the distance between the limit component and the housing when no deformation occurs.

[0047] The technical solution of this invention obtains vehicle state parameters and stiffness curve data of each mount in the powertrain mounting system, establishes a dynamic model of the powertrain mounting system, and determines the vibration data of the mounts. The nonlinear stiffness curve data and vibration data of the mounts are compared with preset data conditions, the stiffness curve data are corrected, and a dynamic correction model is established until the nonlinear stiffness curve data and vibration data of the mounts meet the preset data conditions. Then, based on the vehicle state parameters and preset limit rules, the first limit dimension of the mount is determined. By adopting the stiffness curve design method provided by this invention, and combining the analysis and design of the nonlinear stiffness curve data of the mounts with the actual vehicle operating conditions, the determined mount stiffness curve data is more closely aligned with the actual vehicle driving conditions, improving the reliability of the mounts in reducing noise and vibration transmission, and effectively improving the vehicle's ride comfort.

[0048] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0049] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying 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.

[0050] Figure 1 This is a flowchart illustrating a method for designing the stiffness curve of a powertrain mounting system according to an embodiment of the present invention.

[0051] Figure 2 This is a schematic diagram of a suspension structure provided according to an embodiment of the present invention;

[0052] Figure 3 This is a flowchart illustrating another method for designing the stiffness curve of a powertrain mounting system according to an embodiment of the present invention.

[0053] Figure 4 This is a flowchart illustrating another method for designing the stiffness curve of a powertrain mounting system according to an embodiment of the present invention.

[0054] Figure 5 This is a flowchart illustrating another method for designing the stiffness curve of a powertrain mounting system according to an embodiment of the present invention.

[0055] Figure 6This is a schematic diagram of the stiffness curve data of a mount in a powertrain mounting system according to an embodiment of the present invention;

[0056] Figure 7 This is a schematic diagram of a dynamic model of a powertrain mounting system according to an embodiment of the present invention;

[0057] Figure 8 This is a schematic diagram of the force-compression function relationship of a powertrain mounting system according to an embodiment of the present invention;

[0058] Figure 9 This is a flowchart illustrating another method for designing the stiffness curve of a powertrain mounting system according to an embodiment of the present invention.

[0059] Figure 10 This is a flowchart illustrating another method for designing the stiffness curve of a powertrain mounting system according to an embodiment of the present invention.

[0060] Figure 11 This is a flowchart illustrating another method for designing the stiffness curve of a powertrain mounting system according to an embodiment of the present invention.

[0061] Figure 12 This is a flowchart illustrating another method for designing the stiffness curve of a powertrain mounting system according to an embodiment of the present invention.

[0062] Figure 13 This is a schematic diagram of the structure of a stiffness curve design device for a powertrain mounting system according to an embodiment of the present invention. Detailed Implementation

[0063] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only 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 should fall within the scope of protection of the present invention.

[0064] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0065] This invention provides a method for designing the stiffness curve of a powertrain mounting system. Figure 1 This is a flowchart illustrating a method for designing the stiffness curve of a powertrain mounting system according to an embodiment of the present invention. This embodiment is applicable to the analysis and design of the stiffness curve of a vehicle powertrain mounting system, and the method can be executed by software and / or hardware. Figure 2 This is a schematic diagram of a suspension structure provided in an embodiment of the present invention. The stiffness curve design method for the powertrain suspension system is applied to the powertrain suspension system, which includes multiple suspensions. Each suspension includes a housing 01 and a limiting component 02. The housing includes a cavity 03, and the limiting component 02 is retractably disposed within the cavity 03. See also... Figure 1 The stiffness curve design method for this powertrain mounting system specifically includes:

[0066] S110. Obtain vehicle state parameters and stiffness curve data for each suspension mount.

[0067] Specifically, vehicle state parameters refer to the state parameters of the vehicle during actual operation and the relevant parameters of the vehicle powertrain. For example, the state parameters of the vehicle during actual operation may include parameters such as vehicle speed, engine speed and output torque, while the relevant parameters of the vehicle powertrain may include parameters such as powertrain mass and moment of inertia, powertrain center of gravity, transmission ratio and powertrain mount dynamic-to-static ratio, etc., without limitation.

[0068] A powertrain mounting system typically includes multiple mounts, for example, three or four. Each mount is positioned at a different location on the engine to reduce noise and vibration transmitted from the engine to the vehicle body or frame. Each mount has independent stiffness curve data, which, based on coordinate directions, includes stiffness curve data in three directions—a three-dimensional stiffness curve. Using this three-dimensional stiffness curve data facilitates a comprehensive analysis of the mount's stiffness characteristics from three coordinate directions.

[0069] S120. Based on the vehicle state parameters and stiffness curve data, establish a dynamic model of the powertrain mounting system and determine the vibration data of each mounting.

[0070] Specifically, the vibration data of the suspension mounts consists of relevant state data showing varying degrees of vibration caused by the engine. When analyzing the three-dimensional stiffness curve data of each mount in the powertrain suspension system, the actual operating state of the vehicle is considered, and dynamic analysis software is used to establish a dynamic model of the powertrain suspension system. For example, the dynamic analysis software can be Automatic Dynamic Analysis of Mechanical Systems (Adams) software. By establishing the system dynamic equations using Adams software, static, kinematic, and dynamic analyses of the virtual mechanical system can be performed. In this embodiment, a dynamic model is established for the powertrain suspension system to facilitate the calculation of relevant vibration data of the mounts.

[0071] S130. Compare the nonlinear stiffness curve data and vibration data of each suspension with the preset data conditions, and correct the stiffness curve data according to the comparison results to obtain the dynamic correction model; wherein, the stiffness curve data includes nonlinear stiffness curve data.

[0072] Specifically, the suspension stiffness curve data includes linear stiffness curve data and nonlinear stiffness curve data, with a transition segment between the linear and nonlinear stiffness curve data. Inflection points are set on the transition segment curves, and these inflection points are used to adjust the functional relationship between the linear and nonlinear stiffness curve data within the suspension stiffness curve data.

[0073] This embodiment primarily improves vehicle ride comfort by analyzing and designing nonlinear stiffness curve data. The preset data conditions are the design requirements that the suspension stiffness curve data must meet. The dynamic correction model is a modified model obtained by correcting the initially acquired dynamic model of the powertrain suspension system when the nonlinear stiffness curve data and vibration data of the suspension do not meet the preset data conditions.

[0074] The system generates a comparison result by comparing the nonlinear stiffness curve data from the suspension stiffness curve data and the vibration data calculated based on the dynamic model with preset data conditions. If the comparison result indicates that the nonlinear stiffness curve data or the suspension vibration data does not meet the preset data conditions, the suspension stiffness curve data is corrected based on the preset data conditions, and a dynamic correction model is established. Using the dynamic correction model, the suspension vibration data is recalculated, and the nonlinear stiffness curve data and vibration data are compared with the preset data conditions again. This process continues until the nonlinear stiffness curve data of the suspension meets the requirements of the preset data conditions, resulting in the final optimized suspension stiffness curve data. This allows the suspension stiffness curve data, when applied to the vehicle, to effectively improve the vehicle's ride comfort.

[0075] S140. Based on the comparison results, determine the first limit dimension of the suspension according to the vehicle state parameters and the preset limit rules; wherein, the first limit dimension includes the distance between the limit component and the housing when no deformation occurs.

[0076] Specifically, the preset limit rules are based on vehicle state parameters representing the actual operating state of the vehicle and the vehicle's NVH performance requirements, determining the requirements for the powertrain mounting system to reach a limit during actual vehicle operation. For example, the preset limit rules may include requirements such as the gear position of the vehicle's transmission when the mount reaches the limit, which are not limited here. The first limit dimension is the limit dimension of the mount designed according to the actual operating state of the vehicle and the preset limit rules. This limit dimension is the reserved deformation dimension of the limit component between the mount's initial deformation state and reaching the limit state. The state where the mount reaches the limit can be represented by a certain deformation of the limit component. For example, see... Figure 2 , Figure 2 The distance between the middle limiting component 02 and the housing 01 is represented as the first limiting dimension L.

[0077] When the nonlinear stiffness curve data and vibration data of the suspension meet the requirements of the preset data conditions, the first limit size of the suspension is reasonably determined according to the preset limit rules and in combination with the actual operation of the vehicle. This ensures that the suspension is not in a state of excessive deformation for a long time while meeting the user's requirements for vehicle ride comfort, and provides a certain degree of protection for each suspension in the powertrain suspension system.

[0078] The technical solution of this embodiment obtains vehicle state parameters and stiffness curve data of each mount in the powertrain mounting system, establishes a dynamic model of the powertrain mounting system, and determines the vibration data of the mounts. The nonlinear stiffness curve data and vibration data of the mounts are compared with preset data conditions, the stiffness curve data are corrected, and a dynamic correction model is established until the nonlinear stiffness curve data and vibration data of the mounts meet the preset data conditions. Then, based on the vehicle state parameters and preset limit rules, the first limit dimension of the mount is determined. By adopting the stiffness curve design method provided in this embodiment, and combining the analysis and design of the nonlinear stiffness curve data of the mounts with the actual operating conditions of the vehicle, the determined mount stiffness curve data is more closely aligned with the actual driving conditions of the vehicle, improving the reliability of the mounts in reducing noise and vibration transmission, and effectively improving the vehicle's ride comfort.

[0079] Optionally, Figure 3 This is a flowchart illustrating another method for designing the stiffness curve of a powertrain mounting system according to an embodiment of the present invention. Based on the above embodiments, as... Figure 3 As shown, the vehicle state parameters include vehicle operating data and powertrain parameters. The stiffness curve design method for this powertrain mounting system includes:

[0080] S210. Obtain vehicle state parameters and stiffness curve data for each suspension mount.

[0081] S220. Based on the vehicle status parameters, calculate the gearbox gear used within the preset test time and the corresponding gearbox output torque.

[0082] Specifically, vehicle status parameters may include vehicle speed, engine speed, final drive ratio, and tire radius. Before designing the suspension stiffness curve data, the vehicle is controlled to run for a preset test duration, and vehicle status data is collected in real time. For example, the preset test duration can be set by the user according to actual needs and is not limited here. Generally, the preset test duration can be set to 3 days. After the vehicle has been driven for the preset test duration, the vehicle status parameters within the preset test duration are obtained through the vehicle network. Based on the vehicle status parameters within the preset test duration, the gearbox gears used within the preset test duration and the corresponding gearbox output torque can be calculated according to the corresponding formula.

[0083] The formula for calculating the gearbox gears used within the preset test duration can be expressed as:

[0084]

[0085] Among them, u aThe vehicle's speed is expressed in km / h; r represents the tire radius in meters; n represents the engine speed in rpm / min; i0 represents the final drive ratio; i g This indicates the gear ratio of the transmission, i.e., the gear position of the transmission.

[0086] The formula for calculating the output torque of the transmission, based on each gear, can be expressed as:

[0087] t trans =t para ti g (2)

[0088] Among them, t trans This indicates the output torque of the gearbox, measured in N·m; t para The reference torque of the engine is expressed in N·m; t represents the percentage of the engine's output torque.

[0089] S230. Based on the actual usage time of each gear, determine the utilization rate of each gear and the utilization rate of the output torque of each gear corresponding to each gear.

[0090] Specifically, within a preset test duration, the actual usage time of each transmission gear is determined via the vehicle-to-everything (V2X) network. This actual usage time can include the cumulative duration of use of each gear across multiple discontinuous periods. The gear usage rate is the ratio of the actual usage time of that gear to the preset test duration. Different transmission gears correspond to different transmission output torques, so the transmission output torque usage rate is the ratio of the actual usage time of that output torque to the preset test duration. Therefore, based on the actual usage time of each transmission gear, the usage rate of each transmission gear and the usage rate of each transmission output torque can be determined.

[0091] S240. Based on the vehicle state parameters and stiffness curve data, establish a dynamic model of the powertrain mounting system and determine the vibration data of each mounting.

[0092] S250. Compare the nonlinear stiffness curve data and vibration data of each suspension with the preset data conditions, and correct the stiffness curve data according to the comparison results to obtain the dynamic correction model; wherein, the stiffness curve data includes nonlinear stiffness curve data.

[0093] S260. Based on the comparison results, determine the first limit dimension of the suspension according to the vehicle state parameters and the preset limit rules.

[0094] Optionally, Figure 4 This is a flowchart illustrating another method for designing the stiffness curve of a powertrain mounting system according to an embodiment of the present invention. Based on the above embodiments, as... Figure 4As shown, the stiffness curve design method for this powertrain mounting system includes:

[0095] S310. Obtain vehicle state parameters and stiffness curve data for each suspension mount.

[0096] S320. Based on the vehicle status parameters, calculate the gearbox gear used within the preset test time and the corresponding gearbox output torque.

[0097] S330. Based on the actual usage time of each gear, determine the utilization rate of each gear and the utilization rate of the output torque of each gear.

[0098] S340. Based on the vehicle state parameters and stiffness curve data, establish a dynamic model of the powertrain mounting system and determine the vibration data of each mounting.

[0099] S350. Compare the nonlinear stiffness curve data and vibration data of each suspension with the preset data conditions, and correct the stiffness curve data according to the comparison results to obtain the dynamic correction model; wherein, the stiffness curve data includes nonlinear stiffness curve data.

[0100] S360. When the nonlinear stiffness curve data of the suspension meets the preset data conditions, based on the vehicle operation data and the preset limit rules, the gearbox gear when the second limit dimension reaches the limit dimension threshold and the probability of the second limit dimension reaching the limit dimension threshold are statistically analyzed; wherein, the second limit dimension includes the distance between the limit component and the housing when deformation occurs.

[0101] Specifically, the change in dimension between the limiting component and the housing when the suspension deforms is the second limiting dimension. For example, when the suspension deforms, the rubber pad portion inside the suspension undergoes compression deformation, causing the limiting component to move closer to the housing, thus reducing the second limiting dimension. When the second limiting dimension reaches a certain limiting dimension threshold, it indicates that the suspension is in a limited position.

[0102] When the nonlinear stiffness curve data of the suspension, determined through at least one correction, meets the preset data conditions, the different transmission gears corresponding to when the second limit dimension reaches the limit dimension threshold within the preset test duration can be statistically analyzed based on actual vehicle operating data. For example, statistical analysis shows that the suspension is in a limit state when the transmission gear reaches 6th gear. Therefore, the transmission gears that cause the suspension to reach the limit state include 6th, 7th, 8th, 9th, 10th, 11th, and 12th gears. The probability of the second limit dimension reaching the limit dimension threshold is the ratio of the duration of the suspension in the limit state to the preset test duration. The duration of the suspension in the limit state can include multiple discontinuous time segments during which the suspension reaches the limit state.

[0103] S370. Determine the first limit size of the suspension based on the probability that the gearbox gear and the second limit size reach the limit size threshold when the second limit size reaches the limit size threshold.

[0104] Specifically, based on the actual operating conditions of the vehicle, the calculated transmission gear corresponding to the suspension being in the limit state, and the probability of the suspension being in the limit state, combined with the vehicle's NVH performance requirements, the first limit size of the suspension is reasonably determined. Under the protection of the first limit size, the suspension can effectively reduce the noise and vibration transmitted from the engine to the vehicle body, improving the vehicle's ride comfort, while also protecting the suspension from excessive deformation and reducing the suspension failure rate.

[0105] Optionally, Figure 5 This is a flowchart illustrating another method for designing the stiffness curve of a powertrain mounting system according to an embodiment of the present invention. Based on the above embodiments, as... Figure 5 As shown, the vehicle state parameters include powertrain parameters. The stiffness curve design method for this powertrain mounting system includes:

[0106] S410: Obtain vehicle state parameters and stiffness curve data for each suspension mount.

[0107] S420. Based on the powertrain parameters and stiffness curve data of each mount, determine the triaxial force data of each mount and establish a dynamic model.

[0108] Specifically, Figure 6 This is a schematic diagram of the stiffness curve data of a mount in a powertrain mounting system provided by an embodiment of the present invention. Figure 7 This is a schematic diagram of a dynamic model of a powertrain mounting system provided in an embodiment of the present invention. Figure 6 It is the stiffness curve data of one mount in one direction in the powertrain mounting system. Figure 6 It is a force-displacement function curve converted from the obtained stiffness curve data. Figure 6 This example only illustrates the functional relationship of compression caused by pressure on the suspension; the functional relationship of tension caused by tensile force is not shown. Based on the suspension stiffness curve data, the numerical values ​​of the forces acting on the suspension in the three coordinate directions, i.e., the triaxial forces, are determined, and a system is established. Figure 7 The dynamic model shown is as follows. Wherein, Figure 7 In the diagram, the cuboid represents the engine, the cylinder represents the gearbox, and the axis of the cylinder represents the output shaft of the gearbox, used to apply output torque. Furthermore, the engine has four mounts: mount 1, mount 2, mount 3, and mount 4. Figure 7 The example shown illustrates the use of triaxial force symbols to represent suspension 1, suspension 2, suspension 3, and suspension 4, without any limitation.

[0109] S430: Based on the dynamic model, a preset torque is applied to the output shaft of the gearbox to determine the vibration data of each mount.

[0110] Specifically, by applying a preset torque to the output shaft of the gearbox in the dynamic model to simulate different output torques of the gearbox, each suspension is subjected to different vibration states, thereby determining the vibration data of each suspension under different vibration states.

[0111] S440. Compare the nonlinear stiffness curve data and vibration data of each suspension with the preset data conditions, and correct the stiffness curve data according to the comparison results to obtain the dynamic correction model; wherein, the stiffness curve data includes nonlinear stiffness curve data.

[0112] S450. Based on the comparison results, the first limit dimension of the suspension is determined according to the vehicle state parameters and the preset limit rules.

[0113] Optionally, based on the above embodiments, the vibration data includes attribute parameters and data on the functional relationship between force and compression.

[0114] Based on the dynamic model, a preset torque is applied to the output shaft of the gearbox to determine the vibration data of each mount, including:

[0115] S4301. When the applied preset torque is 0, determine the attribute parameters of each suspension.

[0116] Specifically, the attribute parameters are the basic physical properties of the suspension. For example, the attribute parameters of the suspension may include parameters such as the sixth natural frequency, mode shape, and modal energy distribution. When the preset torque applied to the transmission is 0, the engine is in a vibrating state, but the speed is 0. Multiplying the suspension stiffness curve data by the suspension dynamic-to-static ratio in the powertrain parameters determines the dynamic stiffness of the suspension. Using the dynamic stiffness of the suspension to calculate the attribute parameters improves the accuracy of the attribute parameters and better reflects the actual state of the vehicle.

[0117] S4302. When the applied preset torque is within the preset range, determine the functional relationship data between the force and the compression.

[0118] Specifically, when the torque applied to the transmission output shaft is within a preset range, it indicates that the transmission is in different gears and the engine is at a certain speed. At this time, the mounting brackets will be subjected to different pressures for different gears, resulting in corresponding compression, in order to reduce the transmission of engine vibration and noise to the vehicle body and improve the vehicle's ride comfort. Figure 8 This is a schematic diagram illustrating the force-compression function relationship of a powertrain mounting system according to an embodiment of the present invention. Taking the right front mount as an example, Figure 8The relationship between the force and compression of the right front mount under different gearbox gears is shown, and the mapping relationship between the gearbox gear and the range of force and compression is clearly shown.

[0119] Optionally, Figure 9 This is a flowchart illustrating another method for designing the stiffness curve of a powertrain mounting system according to an embodiment of the present invention. Based on the above embodiments, as... Figure 9 As shown, the vehicle state parameters include powertrain parameters, which include engine idle speed and number of cylinders. The stiffness curve design method for this powertrain mounting system includes:

[0120] S510, Obtain vehicle state parameters and stiffness curve data for each suspension mount;

[0121] S520. Based on the vehicle state parameters and stiffness curve data, establish a dynamic model of the powertrain mounting system and determine the vibration data of each mounting.

[0122] S530. Determine the vibration isolation rate of each mount based on the engine's idle speed and number of cylinders.

[0123] Specifically, the engine's main vibration frequency can be calculated based on the engine's idle speed and number of cylinders. Then, the ratio between the engine's main vibration frequency and the maximum natural frequency of the powertrain mount system is calculated. The maximum natural frequency of the powertrain mount system is the highest of the six natural frequencies calculated from the powertrain mount system's dynamic model. Based on this calculated ratio, the vibration isolation rate of the mount can be calculated using the following formula:

[0124]

[0125] Where μ represents the ratio of the engine’s main vibration frequency to the maximum natural frequency of the powertrain mounting system, and λ represents the damping ratio of the powertrain mounting system, which is a known quantity obtained from the powertrain parameters.

[0126] S540. Compare the vibration isolation rate with the vibration isolation rate threshold to generate the first comparison result.

[0127] Specifically, after calculating the vibration isolation rate of the suspension, the vibration isolation rate is compared with a vibration isolation rate threshold to obtain the first comparison result. For example, the vibration isolation rate threshold can be set by the user according to actual needs, and there is no restriction here.

[0128] S550. Based on the first comparison result, adjust the nonlinear stiffness curve data to meet the preset data conditions; wherein, the preset data conditions include the vibration isolation rate being greater than or equal to the vibration isolation rate threshold.

[0129] Specifically, it is determined whether the obtained first comparison result meets the preset data conditions, that is, the vibration isolation rate of the suspension is greater than or equal to the vibration isolation rate threshold. If the first comparison result meets the preset data conditions, it indicates that the nonlinear stiffness curve data of the suspension meets the requirements for the vibration isolation rate of the suspension, and no adjustment is required. If the first comparison result does not meet the preset data conditions, the stiffness curve data of the suspension is adjusted and corrected according to the first comparison result. Combined with the static compression of the suspension before and after, the linear stiffness curve data of the suspension is reduced, thereby establishing a dynamic correction model and recalculating the relevant vibration data until the vibration isolation rate of the suspension meets the requirements of the preset data conditions.

[0130] S560. Based on the comparison results, determine the first limit dimension of the suspension according to the vehicle state parameters and the preset limit rules.

[0131] Optionally, Figure 10 This is a flowchart illustrating another method for designing the stiffness curve of a powertrain mounting system according to an embodiment of the present invention. Based on the above embodiments, as... Figure 10 As shown, the vibration data includes data on the functional relationship between force and compression. The stiffness curve design method for this powertrain mounting system includes:

[0132] S610: Obtain vehicle state parameters and stiffness curve data for each suspension mount.

[0133] S620. Based on the vehicle state parameters and stiffness curve data, establish a dynamic model of the powertrain mounting system and determine the vibration data of each mounting.

[0134] S630. Determine the static compression of each suspension based on the functional relationship data between the force and compression of each suspension.

[0135] Specifically, the static compression of the mount is the compression corresponding to when the engine output torque is 0. For example, see... Figure 8 The curve within the dashed box represents the functional relationship between force and compression when the transmission is in 12th gear. The functional relationship within the dashed box shows that the static compression of the mount is approximately 4 millimeters when the engine output torque is 0.

[0136] S640. Compare the static compression amount with the compression amount threshold to generate a second comparison result.

[0137] Specifically, the determined static compression amount is compared with a compression amount threshold to obtain a second comparison result. For example, the compression amount threshold can be set by the user according to actual needs, and is not restricted here.

[0138] S650. Based on the second comparison result, adjust the nonlinear stiffness curve data to meet the preset data conditions; wherein, the preset data conditions include that the static compression amount is less than or equal to the compression amount threshold.

[0139] Specifically, it is determined whether the obtained second comparison result meets the preset data condition, that is, the static compression is less than or equal to the compression threshold. If the second comparison result meets the preset data condition, it indicates that the nonlinear stiffness curve data of the suspension meets the requirements for the static compression of the suspension, and no adjustment is required. If the second comparison result does not meet the preset data condition, the linear stiffness curve data of the suspension is added according to the second comparison result. Based on the corrected stiffness curve data, a dynamic correction model is established, and the relevant vibration data are recalculated until the static compression of the suspension meets the requirements of the preset data condition.

[0140] S660. Based on the comparison results, determine the first limit dimension of the suspension according to the vehicle state parameters and the preset limit rules.

[0141] Optionally, Figure 11 This is a flowchart illustrating another method for designing the stiffness curve of a powertrain mounting system according to an embodiment of the present invention. Based on the above embodiments, as... Figure 11 As shown, the stiffness curve data also includes linear stiffness curve data. The stiffness curve design method for this powertrain mounting system includes:

[0142] S710: Obtain vehicle state parameters and stiffness curve data for each suspension mount.

[0143] S720. Based on the vehicle state parameters and stiffness curve data, establish a dynamic model of the powertrain mounting system and determine the vibration data of each mounting.

[0144] S730. Based on the functional relationship data of the force and compression of each suspension, compare the stiffness curve data corresponding to the gearbox gear with the preset stiffness curve data to generate a third comparison result.

[0145] Specifically, in combination Figure 8 The data showing the relationship between the force and compression function of the suspension are used to determine the correspondence between the gears and stiffness curves of the transmission. That is, it is determined that the higher gears of the transmission correspond to linear stiffness curves, and the lower gears correspond to nonlinear stiffness curves; or that the higher gears correspond to nonlinear stiffness curves, and the lower gears correspond to linear stiffness curves, thus obtaining a third comparison result.

[0146] S740. Based on the third comparison result, adjust the inflection point position between the linear stiffness curve data and the nonlinear stiffness curve data to meet the preset data conditions; wherein, the inflection point position includes at least the first inflection point position and the second inflection point position.

[0147] Specifically, see Figure 8 In the functional relationship between the force and compression of the suspension, the linear stiffness curve data corresponds to the linear stiffness segment, and the nonlinear stiffness curve data corresponds to the nonlinear stiffness segment. There is a transition segment between the linear and nonlinear stiffness segments, and this transition segment contains the inflection point between the linear and nonlinear stiffness segments. For example, Figure 8 The area between dashed lines A and B represents the transition segment in the force-compression function relationship. The inflection point positions include at least a first inflection point and a second inflection point, respectively positioned in the transition segment under compression and tension conditions of the suspension. It should be noted that... Figure 8 Only the functional relationship between force and compression under the condition of suspension under pressure is shown.

[0148] S750. Based on the comparison results, the first limit dimension of the suspension is determined according to the vehicle state parameters and the preset limit rules.

[0149] Optionally, Figure 12 This is a flowchart illustrating another method for designing the stiffness curve of a powertrain mounting system according to an embodiment of the present invention. Based on the above embodiments, as... Figure 12 As shown, the stiffness curve design method for this powertrain mounting system includes:

[0150] S810: Obtain vehicle state parameters and stiffness curve data for each suspension mount.

[0151] S820. Based on the vehicle state parameters and stiffness curve data, establish a dynamic model of the powertrain mounting system and determine the vibration data of each mounting.

[0152] S830. Based on the functional relationship data of the force and compression of each suspension, compare the stiffness curve data corresponding to the gearbox gear with the preset stiffness curve data to generate a third comparison result.

[0153] S840. When the high gear of the transmission corresponds to the nonlinear stiffness curve data, determine the position of the first inflection point to satisfy the preset data conditions; wherein, the preset data conditions include that the high gear of the transmission and the linear stiffness curve data have a target mapping relationship.

[0154] Specifically, see [link to relevant documentation] Figure 8 , Figure 8The example illustrates the distribution of gearbox gears in the functional relationship between force and compression, showing that as the suspension compression gradually decreases, the gearbox gear gradually increases. If the third comparison result indicates that the high gear of the gearbox corresponds to nonlinear stiffness curve data, the position of the first inflection point is adjusted so that the mapping relationship between the high gear of the gearbox and the stiffness curve data meets the preset data conditions, i.e., the high gear of the gearbox corresponds to the linear stiffness segment. Establishing a target mapping relationship between the high gear of the gearbox and the linear stiffness curve data ensures that when the vehicle's gearbox is in a high gear, the suspension has a smaller compression, which to some extent improves the vehicle's ride comfort and protects the suspension from damage.

[0155] S850. When the low gear of the transmission corresponds to the linear stiffness curve data, determine the position of the second inflection point to satisfy the preset data conditions; wherein, the preset data conditions include that the low gear of the transmission and the nonlinear stiffness curve data have a target mapping relationship.

[0156] Specifically, see [link to relevant documentation] Figure 8 If the third comparison result indicates that the low gear of the transmission corresponds to the linear stiffness curve data, then the position of the second inflection point is adjusted so that the mapping relationship between the low gear of the transmission and the stiffness curve data meets the preset data conditions, that is, the low gear of the transmission corresponds to the nonlinear stiffness segment. By establishing a target mapping relationship between the low gear of the transmission and the nonlinear stiffness curve data, when the vehicle's transmission is in a low gear, the suspension can generate corresponding compression based on the actual operating state of the vehicle, thereby improving the vehicle's ride comfort.

[0157] S860. Based on the comparison results, the first limit dimension of the suspension is determined according to the vehicle state parameters and the preset limit rules.

[0158] This invention also provides a device for designing the stiffness curve of a powertrain mounting system. Figure 13 This is a schematic diagram of the structure of a stiffness curve design device for a powertrain mounting system provided in an embodiment of the present invention. Figure 13 As shown, the stiffness curve design device 100 for the powertrain mounting system includes:

[0159] The data acquisition module 10 is used to acquire vehicle state parameters and stiffness curves of each suspension.

[0160] The model building module 20 is used to build a dynamic model of the powertrain mounting system based on vehicle state parameters and stiffness curve data, and to determine the vibration data of each mounting.

[0161] The result comparison and correction module 30 is used to compare the nonlinear stiffness curve data of each suspension with preset data conditions, correct the stiffness curve data according to the comparison results, and obtain a dynamic correction model; wherein, the stiffness curve data includes nonlinear stiffness curve data.

[0162] The limit size design module 40 is used to determine the first limit size of the suspension based on the comparison results, vehicle state parameters and preset limit rules; wherein, the first limit size includes the distance between the limit component and the housing when no deformation occurs.

[0163] The stiffness curve design device for the powertrain mounting system provided in this embodiment of the invention can execute the stiffness curve design method for the powertrain mounting system provided in any embodiment of the invention, and has the corresponding functional modules and beneficial effects of the method.

[0164] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A method for designing the stiffness curve of a powertrain mounting system, characterized in that, The stiffness curve design method for the powertrain mounting system is applied to the powertrain mounting system, which includes multiple mounts. Each mount includes a housing and a limiting component. The housing includes a cavity, and the limiting component is retractably disposed within the cavity. The design method includes: Obtain vehicle status parameters and stiffness curve data for each suspension mount; Based on the vehicle state parameters and the stiffness curve data, a dynamic model of the powertrain mounting system is established, and the vibration data of each mounting is determined. The nonlinear stiffness curve data and vibration data of each suspension are compared with preset data conditions, and the stiffness curve data are corrected according to the comparison results to obtain a dynamic correction model; wherein, the stiffness curve data includes nonlinear stiffness curve data; Based on the comparison results, the first limiting dimension of the suspension is determined according to the vehicle state parameters and the preset limiting rules; wherein, the first limiting dimension includes the distance between the limiting component and the housing when no deformation occurs; the preset limiting rules include the gear requirement of the vehicle transmission when the suspension reaches the limit. The vehicle status parameters include vehicle operating data and powertrain parameters; Before establishing the dynamic model of the powertrain mounting system based on the vehicle state parameters and the stiffness curve data, and determining the vibration data of each mounting, the method further includes: Based on the vehicle state parameters, calculate the gearbox gear used within the preset test duration and the corresponding gearbox output torque; Based on the actual usage time of each gear, determine the utilization rate of each gear and the utilization rate of the output torque of each gear corresponding to each gear. The step of determining the first limiting dimension of the suspension based on the comparison result, according to the vehicle state parameters and preset limiting rules, includes: When the nonlinear stiffness curve data of the suspension meets the preset data conditions, according to the vehicle operation data and the preset limit rules, the gearbox gear position when the second limit dimension reaches the limit dimension threshold and the probability of the second limit dimension reaching the limit dimension threshold are statistically analyzed; wherein, the second limit dimension includes the distance between the limit component and the housing when deformation occurs; The first limit size of the suspension is determined based on the gearbox gear position when the second limit size reaches the limit size threshold and the probability that the second limit size reaches the limit size threshold.

2. The method for designing the stiffness curve of the powertrain mounting system according to claim 1, characterized in that, The vehicle status parameters include powertrain parameters; The step of establishing a dynamic model of the powertrain mounting system based on the vehicle state parameters and the stiffness curve data, and determining the vibration data of each mounting, includes: Based on the powertrain parameters and the stiffness curve data of each suspension, the triaxial force data of each suspension are determined, and the dynamic model is established. Based on the aforementioned dynamic model, a preset torque is applied to the output shaft of the gearbox to determine the vibration data of each of the aforementioned suspensions.

3. The method for designing the stiffness curve of the powertrain mounting system according to claim 2, characterized in that, The vibration data includes attribute parameters and data on the functional relationship between force and compression. The step of applying a preset torque to the output shaft of the gearbox based on the dynamic model and determining the vibration data of each of the aforementioned mounts includes: When the applied preset torque is 0, determine the attribute parameters of each of the suspensions; When the applied preset torque is within a preset range, the functional relationship data between the force and the compression amount is determined.

4. The method for designing the stiffness curve of the powertrain mounting system according to claim 1, characterized in that, The vehicle status parameters include powertrain parameters, which include engine idle speed and number of cylinders; The step of comparing the nonlinear stiffness curve data of each of the suspensions with preset data conditions, and correcting the stiffness curve data according to the comparison results, includes: The vibration isolation rate of each mount is determined based on the idle speed and the number of cylinders of the engine. The vibration isolation rate is compared with the vibration isolation rate threshold to generate a first comparison result; Based on the first comparison result, the nonlinear stiffness curve data is adjusted to meet the preset data conditions; wherein, the preset data conditions include the vibration isolation rate being greater than or equal to the vibration isolation rate threshold.

5. The method for designing the stiffness curve of the powertrain mounting system according to claim 4, characterized in that, The vibration data includes data on the functional relationship between force and compression. The step of comparing the nonlinear stiffness curve data of each of the suspensions with preset data conditions and correcting the stiffness curve data based on the comparison results further includes: Based on the functional relationship data between the force and the compression of each suspension, the static compression of each suspension is determined; The static compression amount is compared with the compression amount threshold to generate a second comparison result; Based on the second comparison result, the nonlinear stiffness curve data is adjusted to meet the preset data conditions; wherein, the preset data conditions include the static compression amount being less than or equal to the compression amount threshold.

6. The method for designing the stiffness curve of the powertrain mounting system according to claim 5, characterized in that, The stiffness curve data also includes linear stiffness curve data; The step of comparing the nonlinear stiffness curve data of each of the suspensions with preset data conditions and correcting the stiffness curve data based on the comparison results further includes: Based on the functional relationship data of the force and compression of each of the aforementioned suspensions, the stiffness curve data corresponding to the gearbox gear is compared with the preset stiffness curve data to generate a third comparison result; Based on the third comparison result, the inflection point position between the linear stiffness curve data and the nonlinear stiffness curve data is adjusted to meet the preset data conditions; wherein, the inflection point position includes at least a first inflection point position and a second inflection point position.

7. The method for designing the stiffness curve of the powertrain mounting system according to claim 6, characterized in that, The step of adjusting the inflection point position between the linear stiffness curve data and the nonlinear stiffness curve data according to the third comparison result to meet the preset data conditions includes: When the high gear of the transmission corresponds to the nonlinear stiffness curve data, the position of the first inflection point is determined to satisfy the preset data conditions; wherein, the preset data conditions include that the high gear of the transmission and the linear stiffness curve data have a target mapping relationship; When the low gear of the transmission corresponds to the linear stiffness curve data, the position of the second inflection point is determined to satisfy the preset data conditions; wherein, the preset data conditions include that the low gear of the transmission and the nonlinear stiffness curve data have a target mapping relationship.

8. A stiffness curve design apparatus for a powertrain mounting system, used to execute the stiffness curve design method for a powertrain mounting system as described in any one of claims 1-7, characterized in that, The stiffness curve design device for the powertrain mounting system is applied to the powertrain mounting system, which includes multiple mounts. Each mount includes a housing and a limiting component. The housing includes a cavity, and the limiting component is telescopically disposed within the cavity. The stiffness curve design device for the powertrain mounting system includes: The data acquisition module is used to acquire vehicle state parameters and stiffness curve data of each suspension mount; The model building module is used to build a dynamic model of the powertrain mounting system based on the vehicle state parameters and the stiffness curve data, and to determine the vibration data of each mounting. The result comparison and correction module is used to compare the nonlinear stiffness curve data of each suspension with preset data conditions, and correct the stiffness curve data according to the comparison results to obtain a dynamic correction model; wherein, the stiffness curve data includes nonlinear stiffness curve data. The limit size design module is used to determine the first limit size of the suspension based on the comparison result, the vehicle state parameters, and the preset limit rules; wherein, the first limit size includes the distance between the limit component and the housing when no deformation occurs.

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