Novel automobile suspension internal and external buffer block gap and rigidity design method

Abstract

The invention provides a novel automobile suspension internal and external buffer block gap and rigidity design method. The method comprises the following steps: establishing a suspension dynamical model; parallel wheel jump simulation analysis is carried out on the suspension dynamical model, so that the wheel jump stroke during initial contact of a built-in buffer block meets a set contact gap stroke target value; the post-processing module is used for extracting a relation curve of wheel jump and wheel load, calculating suspension rigidity and full-load offset frequency, determining wheel center loads of an operation stability limit stroke and a wheel jump limit stroke, adjusting the rigidity of a built-in buffer block, enabling the suspension offset frequency to meet a set full-load offset frequency target value, and recording the compression amount L1 of the built-in buffer block during full load; the rigidity of the built-in buffer block above the compression amount L1 is adjusted based on the operation stability limit stroke wheel center load FL2g, so that the operation 2G wheel jump stroke meets the set operation stability limit stroke target value; the gap of the external buffer block is subjected to secondary calibration, so that the wheel jump stroke during contact of the external buffer block is consistent with an operation stability limit stroke target value; based on the wheel center load FL5g of the wheel jump limit stroke, the rigidity of the internal buffer block and the rigidity of the external buffer block are adjusted, so that the 5G operation wheel jump stroke meets the set wheel jump limit stroke target value; and outputting parameters of the gap and rigidity of the internal buffer block and the gap and rigidity of the external buffer block which meet the target.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle engineering, and particularly to a method for designing the gap and stiffness of internal and external buffer blocks of a new type of automobile suspension. Background Art

[0002] With the rapid development of the domestic self-owned brand automobile industry in recent years, customers have higher and higher requirements for the performance of pickup trucks. Designing a pickup truck with strong load-carrying capacity, good handling stability and ride comfort has become a challenge for each main engine factory.

[0003] The difference in axle loads between the empty and full loads of pickup truck models is relatively large, and the spring stiffness cannot meet the requirements of the natural frequencies of the empty and full loads. Currently, a small-stiffness internal buffer block is used to provide stiffness. However, the natural frequency of the full load is too small, which will have a greater impact on the handling stability of the vehicle. The requirements for the length and stiffness of the buffer block for pickup truck models are also correspondingly higher and higher. The mechanical properties of the buffer block directly determine the total upward travel of the suspension, the handling stability of the whole vehicle, the ride comfort, and the peak load of the vehicle body. If the upward travel is too large, it will affect the layout space of the parts. If the upward travel is too small, it may lead to insufficient energy absorption of the suspension when the whole vehicle bounces, affecting the ride comfort. At the same time, the energy storage capacity of the buffer block itself also affects the peak load of the vehicle body. The greater the energy storage, the smaller the peak load of the vehicle body, and the easier it is to meet the strength requirements of the parts. In the full-load state, the buffer block will be compressed. The softer the buffer block, the greater the full-load compression amount, and the smaller the ground clearance. In addition, the buffer block can also increase the vertical stiffness and roll stiffness of the whole vehicle, provide a certain lateral support for the whole vehicle during steering, and reduce the roll gradient. Summary of the Invention

[0004] The present invention provides a method for designing the gap and stiffness of internal and external buffer blocks of a new type of automobile suspension, which is to design two internal and external buffer blocks to facilitate meeting the natural frequency of the suspension under full load, and reasonably design the stiffness and gap matching of the internal and external buffer blocks to enable the vehicle to have better ride comfort and load-carrying and cargo-pulling capabilities.

[0005] The present invention provides a method for designing the gap and stiffness of internal and external buffer blocks of a new type of automobile suspension. The internal buffer block is placed inside the spring, and the external buffer block is used to limit the extreme travel of the suspension, including the following steps: Establish a suspension dynamics model; Conduct a parallel wheel-hop simulation analysis on the suspension dynamics model to make the wheel-hop travel at the initial contact of the internal buffer block meet the set contact gap travel target value; Extract the relationship curve between wheel-hop and wheel load in the post-processing module, calculate the suspension stiffness and the natural frequency of the full load, determine the wheel center load of the handling stability extreme travel and the wheel-hop extreme travel, adjust the stiffness of the internal buffer block to make the natural frequency of the suspension meet the set full-load natural frequency target value, and record the compression amount L1 of the internal buffer block at full load; Based on the wheel center load F of the handling stability extreme travelL2g Adjust the stiffness of the built-in buffer block above the compression amount L1 to make the wheel hop stroke of operation 2G meet the set handling and stability limit stroke target value; Perform secondary calibration on the external buffer block clearance to make the wheel hop stroke when the external buffer block contacts consistent with the handling and stability limit stroke target value; Wheel center load F based on the wheel hop limit stroke L5g Adjust the stiffness of the internal and external buffer blocks to make the wheel hop stroke of operation 5G meet the set wheel hop limit stroke target value; Output the internal buffer block clearance and stiffness, external buffer block clearance and stiffness parameters that meet the target.

[0006] According to the new method for designing the internal and external buffer block clearance and stiffness of a new type of automotive suspension provided by the present invention, the establishment of the suspension dynamics model includes: Obtain the suspension type of the vehicle model and interpret the structures of the suspension system and the steering system; Extract the hard points in the digital model; Establish the suspension system, steering system, and anti-roll bar templates in the Template of Adams / car; In the standard mode of Adams / car, use the templates established in the Template to establish the subsystems of the suspension, steering, and anti-roll bar; Assemble each subsystem into an assembly; Input the extracted hard points into the assembly, write the attribute files of each component, and assign them to the assembly to generate a complete suspension dynamics model.

[0007] Before the steps of establishing the suspension dynamics model according to the new method for designing the internal and external buffer block clearance and stiffness of a new type of automotive suspension provided by the present invention, it includes: Set the contact clearance stroke target value, full-load natural frequency target value, handling and stability limit stroke target value, and wheel hop limit stroke target value according to the vehicle performance.

[0008] According to the new method for designing the internal and external buffer block clearance and stiffness of a new type of automotive suspension provided by the present invention, the parallel wheel hop simulation analysis of the suspension dynamics model to make the wheel hop stroke meet the contact clearance stroke target value includes: Adjust the external buffer block clearance value; Input the initial clearance value to perform parallel wheel hop simulation analysis on the established suspension dynamics model, and extract the relationship curve between the wheel hop and the buffer block force in the post-processing module; Read the wheel hop stroke when the buffer block just bears force, that is, the wheel hop stroke when contacting the buffer block; Compare the wheel hop stroke when contacting the buffer block with the set contact clearance stroke target value; If the wheel hop travel when contacting the buffer block is greater than the set target value of the contact clearance travel, the clearance value in the suspension dynamics model is decreased; If the wheel hop travel when contacting the buffer block is less than the set target value of the contact clearance travel, the clearance value in the suspension dynamics model is increased; When the wheel hop travel when contacting the buffer block meets the set target value of the contact clearance travel, confirm that the clearance value in the suspension dynamics model is the buffer block clearance.

[0009] According to the new method for designing the internal and external buffer block clearances and stiffness of a vehicle suspension provided by the present invention, the suspension stiffness is determined by the slope of the wheel load relationship curve within the range of ±5 mm of the wheel hop amount at full load, where Wheel load at full load: F_full = M_full * g / 2; Suspension natural frequency: ; K is the suspension stiffness, and M 满簧上 is the sprung mass at full load.

[0010] According to the new method for designing the internal and external buffer block clearances and stiffness of a vehicle suspension provided by the present invention, adjusting the stiffness of the internal buffer block to make the suspension natural frequency meet the set target value of the full load natural frequency, and recording the compression amount L1 of the buffer block at full load, includes: If the suspension natural frequency is less than the set target value of the full load natural frequency, increase the stiffness value of the internal buffer block; If the suspension natural frequency is greater than the set target value of the full load natural frequency, decrease the stiffness value of the internal buffer block; When the suspension natural frequency meets the set target value of the full load natural frequency, extract the relationship curve between the wheel hop and the force on the internal buffer block in the post-processing module, read the force value of the internal buffer block when the wheel hop is at full load, and read the compression amount L1 of the buffer block at this force value.

[0011] According to the new method for designing the internal and external buffer block clearances and stiffness of a vehicle suspension provided by the present invention, based on the wheel center load F at the handling and stability limit travel L2g Adjust the stiffness of the internal buffer block above the compression amount L1 to make the handling and stability 2G wheel hop travel meet the set target value of the handling and stability limit travel; before that includes: Calculate the wheel center load at the handling and stability limit travel and the wheel center load at the wheel hop limit travel; Among them, the wheel center load at the handling and stability limit travel: F L2g = M * g; The wheel center load at the wheel hop limit travel: F L5g = 5 * (M_full - m) * g / 2; F L2g : The wheel center load at the handling and stability limit travel; F L5g : The wheel center load at the wheel hop limit travel; M: Half-loaded front axle or rear axle mass; M full: Full-loaded front axle or rear axle mass; m: Unsprung mass of the front axle or rear axle; g: Acceleration due to gravity.

[0012] According to the novel design method for the gaps and stiffness of internal and external buffer blocks of an automotive suspension provided by the present invention, for the wheel center load F based on the handling and stability limit stroke L2g Adjust the stiffness of the internal buffer block above the compression amount L1 so that the handling and stability 2G wheel hop stroke meets the set handling and stability limit stroke target value, including: Under the condition of meeting the buffer block gap, conduct a parallel wheel hop condition simulation analysis on the suspension dynamic model, and establish a relationship curve between the wheel hop stroke and the wheel center load; Based on the calculated wheel center load of the handling and stability limit stroke, read the wheel hop stroke under the wheel center load of the handling and stability limit stroke on the relationship curve between the wheel hop stroke and the wheel center load, that is, the 2G wheel hop stroke; Compare the 2G wheel hop stroke with the set handling and stability limit stroke target value; If the 2G wheel hop stroke is greater than the set handling and stability limit stroke target value, modify the buffer block property file to increase the stiffness of the buffer block above the compression amount L1; If the 2G wheel hop stroke is less than the set handling and stability limit stroke target value, modify the buffer block property file to decrease the stiffness of the buffer block above the compression amount L1; When the 2G wheel hop stroke meets the handling and stability limit stroke target value, confirm the buffer block stiffness.

[0013] According to the novel design method for the gaps and stiffness of internal and external buffer blocks of an automotive suspension provided by the present invention, for the secondary calibration of the external buffer block gap to make the wheel hop stroke when the external buffer block contacts consistent with the handling and stability limit stroke target value; including: Under the condition of meeting the buffer block stiffness, adjust the external buffer block gap, and then conduct a parallel wheel hop condition simulation analysis on the suspension dynamic model, and establish a relationship curve between the wheel hop stroke and the force on the external buffer block; Read the wheel hop stroke when the external buffer block is stressed. If the wheel hop amount at this time is greater than the set handling and stability limit stroke target value, decrease the external buffer block gap value; If the wheel hop amount at this time is less than the set handling and stability limit stroke target value, increase the external buffer block gap value; When the wheel hop stroke of the external buffer block meets the handling and stability limit stroke target value, confirm the gap of the external buffer block.

[0014] According to the novel design method for the gaps and stiffness of internal and external buffer blocks of an automotive suspension provided by the present invention, for the wheel center load F based on the wheel hop limit stroke L5gAdjust the stiffness of the internal and external buffer blocks to make the 5G wheel jump stroke meet the set wheel jump limit stroke target value, including: Under the condition that the buffer block gap and the confirmed buffer block stiffness are satisfied, the suspension dynamics model is again subjected to parallel wheel hop condition simulation analysis to establish a relationship curve between wheel hop stroke and wheel center load; By calculating the wheel center load of the wheel jump limit stroke, the wheel jump stroke under the wheel center load of the wheel jump limit stroke is read from the relationship curve between the wheel jump stroke and the wheel center load, that is, the 5G wheel jump stroke; Compare the 5G wheel jump stroke with the set wheel jump limit stroke target value; If the 5G wheel jump stroke is greater than the set wheel jump limit stroke target value, modifying the buffer block attribute file only increases the stiffness of the buffer block; If the 5G wheel jump stroke is less than the set wheel jump limit stroke target value, modifying the buffer block attribute file only reduces the stiffness of the buffer block; When the 5G wheel jump stroke meets the wheel jump limit stroke target value, confirm the buffer block stiffness after adjustment of the buffer block.

[0015] The present invention provides a novel method for designing the clearance and stiffness of internal and external buffer blocks of automobile suspension. The internal buffer block is placed in the spring, and the external buffer block is used to limit the extreme travel of the suspension. The internal and external buffer blocks are used to achieve relatively consistent suspension deviation frequencies when empty and fully loaded. The dams / car software is used to establish a dynamic model, analyze and design the stiffness of the internal and external buffer blocks, and reduce the development cycle; it is convenient to meet the suspension deviation frequency when fully loaded, and the clearance of the internal buffer block is reasonably designed to ensure the smoothness of the vehicle when it is empty, and when the vehicle passes over a bump or There is no abrupt feeling when passing a pothole; it can also provide reasonable lateral support to ensure the vehicle's handling stability; the full-load bias frequency is reasonably designed to ensure the vehicle's handling stability and carrying capacity; the 2g stroke is reasonably designed, and the wheel jump is reduced when the wheel leaves the ground, maximizing comfort; the gap of the external buffer block is reasonably designed, and in order to improve the comfort of the vehicle, the external buffer block should be as close to the external buffer block as possible during the 2g stroke; the 5G stroke is reasonably designed to prevent excessive wheel jump and tire wear, and too little wheel jump and poor performance. Reasonable design of the stiffness and clearance of the internal and external buffer blocks gives the vehicle better riding comfort and load-carrying capacity. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 It is a schematic flow chart of a method for designing the gap and stiffness of internal and external buffer blocks of a new type of automotive suspension provided by an embodiment of the present invention.

[0018] Figure 2 It is a schematic diagram of a suspension dynamics model provided by an embodiment of the present invention.

[0019] Figure 3 It is a schematic structural diagram of internal and external buffer blocks provided by an embodiment of the present invention.

[0020] Figure 4 It is a schematic diagram of a buffer block property file in the suspension dynamics model provided by an embodiment of the present invention.

[0021] Figure 5 It is a schematic diagram of the relationship between the 2G and 5G wheel center loads and the wheel hop stroke in the suspension dynamics model provided by an embodiment of the present invention.

[0022] Figure 6 It is a schematic diagram of the relationship between the force on the buffer block and the wheel hop provided by an embodiment of the present invention.

[0023] Reference numerals: 1. Internal buffer block; 2. External buffer block. Detailed implementation manners

[0024] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions in the present invention will be clearly and completely described below with reference to the accompanying drawings in the present invention. Obviously, the described embodiments are some but not all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art without creative efforts based on the embodiments in the present invention belong to the scope of protection of the present invention.

[0025] The following combines Figures 1-6 to describe a method for designing the gap and stiffness of internal and external buffer blocks of a new type of automotive suspension of the present invention.

[0026] An embodiment of the present invention provides a method for designing the gap and stiffness of internal and external buffer blocks of a new type of automotive suspension. As Figure 1 shown, it includes the following steps: S100: Establish a suspension dynamics model; S200: Conduct a parallel wheel hop simulation analysis on the suspension dynamics model to make the wheel hop stroke at the initial contact of the internal buffer block 1 meet the set contact gap stroke target value; S300: The post-processing module extracts the relationship curve between wheel hop and wheel load, calculates the suspension stiffness and the full-load natural frequency, determines the wheel center loads at the handling and stability limit travel and the wheel hop limit travel, adjusts the stiffness of the built-in buffer block 1 so that the suspension natural frequency meets the set full-load natural frequency target value, and records the compression amount L1 of the built-in buffer block 1 at full load; S400: Based on the wheel center load F at the handling and stability limit travel L2g Adjust the stiffness of the built-in buffer block 1 above the compression amount L1 so that the 2G wheel hop travel meets the set handling and stability limit travel target value; S500: Second calibration of the clearance of the external buffer block 2 so that the wheel hop travel at the contact of the external buffer block 2 is consistent with the handling and stability limit travel target value; S600: Based on the wheel center load F at the wheel hop limit travel L5g Adjust the stiffness of the internal and external buffer blocks so that the 5G wheel hop travel meets the set wheel hop limit travel target value; S700: Output the parameters of the clearance and stiffness of the built-in buffer block 1 and the clearance and stiffness of the external buffer block 2 that meet the targets.

[0027] In a specific embodiment, establishing the suspension dynamics model in step S100 includes: S101: Obtain the suspension type of the vehicle model and interpret the structures of the suspension system and the steering system; S102: Extract the hard points in the digital model; S103: Establish the templates of the suspension system, the steering system, and the stabilizer bar in the Template of Adams / car; S104: In the standard mode of Adams / car, use the templates established in the Template to establish the subsystems of the suspension, the steering, and the stabilizer bar; S105: Assemble each subsystem into an assembly; S106: Input the extracted hard points into the assembly, write the property files of the bushings, springs, shock absorbers, etc., and assign them to the assembly to generate a complete suspension dynamics model.

[0028] In this embodiment, before step S100, it includes: setting the contact clearance travel target value, the full-load natural frequency target value, the handling and stability limit travel target value, and the wheel hop limit travel target value according to the vehicle performance.

[0029] Specifically, the system objectives are decomposed from the vehicle performance objectives. For example, the vehicle performance requires strong body control, and a certain support rod is needed during turning. Through the subjective evaluation of the benchmark model, it is found that the vehicle's buffer block intervenes late, the body movement is smoother during the vehicle roll control process, but the support rod is relatively weak, and the contact clearance stroke, such as the contact clearance stroke of the vehicle is 30 mm. To meet the vehicle performance requirements, the system objective contact buffer block stroke can be set to 15 - 20 mm, and it is not allowed to contact the buffer block too early. Similarly, the full-load natural frequency, handling and stability limit stroke, and wheel hop limit stroke are set.

[0030] In this embodiment, step S200 includes: S201: Adjust the clearance value of the external buffer block 2; S202: Input the initial clearance value to perform a parallel wheel hop simulation analysis on the established suspension dynamics model, and extract the relationship curve between wheel hop and buffer block force in the post-processing module; S203: Read the wheel hop stroke when the internal buffer block 1 just starts to be stressed, that is, the wheel hop stroke when contacting the internal buffer block 1; S204: Compare the wheel hop stroke when contacting the internal buffer block 1 with the set contact clearance stroke target value; S205: If the wheel hop stroke when contacting the internal buffer block 1 is greater than the set contact clearance stroke target value, reduce the clearance value in the suspension dynamics model; S206: If the wheel hop stroke when contacting the internal buffer block 1 is less than the set contact clearance stroke target value, increase the clearance value in the suspension dynamics model; S207: When the wheel hop stroke when contacting the internal buffer block 1 meets the set contact clearance stroke target value, confirm the clearance value in the suspension dynamics model as the buffer block clearance.

[0031] Among them, in step S300, the suspension stiffness is determined by the slope of the wheel load relationship curve within the range of ±5 mm of the wheel hop amount at full load, where Wheel load at full load: F_full = M_full * g / 2; Suspension natural frequency: ; K is the suspension stiffness, and M 满簧上 is the unsprung mass at full load.

[0032] In step S300, adjust the stiffness of the internal buffer block 1 so that the suspension natural frequency meets the set full-load natural frequency target value, and record the buffer block compression amount L1 at full load, including: If the suspension natural frequency is less than the set full-load natural frequency target value, increase the stiffness value of the internal buffer block 1; If the suspension natural frequency is greater than the set full-load natural frequency target value, reduce the stiffness value of the internal buffer block 1; When the suspension partial frequency meets the set full-load partial frequency target value, the post-processing module extracts the relationship curve between the wheel hop and the force on the built-in buffer block 1, reads the force value of the built-in buffer block 1 when the full-load wheel hop occurs, and reads the buffer block compression amount L1 at this force value.

[0033] Before step S400, it includes: calculating the wheel center load of the handling and stability limit stroke and the wheel center load of the wheel hop limit stroke; Among them, the wheel center load of the handling and stability limit stroke: F L2g = M * g; The wheel center load of the wheel hop limit stroke: F L5g = 5 * (M_full - m) * g / 2; F L2g : The wheel center load of the handling and stability limit stroke; F L5g : The wheel center load of the wheel hop limit stroke; M: The mass of the front axle or rear axle at half load; M_full: The mass of the front axle or rear axle at full load; m: The unsprung mass of the front axle or rear axle; g: The acceleration due to gravity.

[0034] Step S400 includes: S401: Conduct a parallel wheel hop condition simulation analysis on the suspension dynamic model under the condition of meeting the buffer block clearance, and establish a relationship curve between the wheel hop stroke and the wheel center load; S402: Through the calculated wheel center load of the handling and stability limit stroke, read the wheel hop stroke at the wheel center load of the handling and stability limit stroke on the relationship curve between the wheel hop stroke and the wheel center load, that is, the 2G wheel hop stroke; S403: Compare the 2G wheel hop stroke with the set handling and stability limit stroke target value; S404: If the 2G wheel hop stroke is greater than the set handling and stability limit stroke target value, modify the attribute file of the built-in buffer block 1 to increase the stiffness above the buffer block compression amount L1; S405: If the 2G wheel hop stroke is less than the set handling and stability limit stroke target value, modify the attribute file of the built-in buffer block 1 to decrease the stiffness above the buffer block compression amount L1; S406: When the 2G wheel hop stroke meets the handling and stability limit stroke target value, confirm the stiffness of the built-in buffer block 1; The schematic diagram of the buffer block attribute file is as Figure 4 shown.

[0035] Step S500 includes: S501: Under the condition of meeting the buffer block stiffness, adjust the clearance of the external buffer block 2, and then conduct a parallel wheel hop condition simulation analysis on the suspension dynamic model to establish a relationship curve between the wheel hop stroke and the force on the external buffer block 2; S502: Read the wheel hop travel when the external buffer block 2 is stressed. If the wheel hop amount at this time is greater than the set handling and ride limit travel target value, then decrease the clearance value of the external buffer block 2; S503: If the wheel hop amount at this time is less than the set handling and ride limit travel target value, then increase the clearance value of the external buffer block 2; S504: When the wheel hop travel of the external buffer block 2 meets the handling and ride limit travel target value, confirm the clearance of the external buffer block 2.

[0036] Further, step S600 includes: S601: Under the condition of meeting the clearance of the external buffer block 2 and the confirmed stiffness of the external buffer block 2, perform a parallel wheel hop condition simulation analysis on the suspension dynamic model again, and establish a relationship curve between the wheel hop travel and the wheel center load as Figure 5 shown; S602: Through the wheel center load of the calculated wheel hop limit travel, read the wheel hop travel under the wheel center load of the wheel hop limit travel on the relationship curve between the wheel hop travel and the wheel center load, that is, the 5G wheel hop travel; S603: Compare the 5G wheel hop travel with the set wheel hop limit travel target value; S604: If the 5G wheel hop travel is greater than the set wheel hop limit travel target value, then modify the property file of the external buffer block 2 to only increase the stiffness of the buffer block; S605: If the 5G wheel hop travel is less than the set wheel hop limit travel target value, then modify the property file of the external buffer block 2 to only decrease the stiffness of the buffer block; S606: When the 5G wheel hop travel meets the wheel hop limit travel target value, confirm the adjusted buffer block stiffness of the external buffer block 2, and the relationship between the wheel hop travel and the wheel center load is as Figure 6 shown.

[0037] The embodiment of the present invention provides a method for designing the clearance and stiffness of the internal and external buffer blocks of a new type of automobile suspension, including the following steps: S1: Set the contact clearance travel target value, full load natural frequency target value, handling and ride limit travel target value, and wheel hop limit travel target value according to the vehicle performance; S2: Establish a suspension dynamic model; the generated suspension dynamic model is as Figure 2 shown.

[0038] S3: First, increase the clearance value of the external buffer block 2 to ensure that it does not contact the external buffer block 2 during the 2G travel; S4: Input the initial clearance value to perform a parallel wheel hop simulation analysis on the established suspension dynamic model, and extract the relationship curve between the wheel hop and the force on the internal buffer block 1 in the post-processing module; read the wheel hop travel when the internal buffer block 1 is just stressed, that is, the wheel hop travel when contacting the internal buffer block 1; S5: Compare the wheel hop travel when contacting the built-in buffer block 1 with the set target value of the contact clearance travel; S5: Whether the wheel hop travel when contacting the built-in buffer block 1 meets the set target value of the contact clearance travel; If so, execute step S8; If not, when the wheel hop travel when contacting the built-in buffer block 1 is greater than the set target value of the contact clearance travel, execute step S6; when the wheel hop travel when contacting the built-in buffer block 1 is less than the set target value of the contact clearance travel, execute step S7; S6: Reduce the clearance value in the suspension dynamics model; conduct a parallel wheel hop simulation analysis on the established suspension dynamics model again; execute step S4; S7: Increase the clearance value in the suspension dynamics model; conduct a parallel wheel hop simulation analysis on the established suspension dynamics model again; execute step S4; S8: Confirm the clearance of the built-in buffer block 1; S9: Extract the relationship curve between wheel hop and wheel load in the post-processing module, read the wheel hop amount at full load, calculate the suspension stiffness and suspension natural frequency, and the suspension stiffness is the slope value K within ±5 mm of this wheel hop amount; Wheel load at full load: F_full = M_full * g / 2; Suspension natural frequency: ; S10: Adjust the stiffness of the built-in buffer block 1 to make the suspension natural frequency meet the set target value of the full-load natural frequency. If the suspension natural frequency is less than the set target value of the full-load natural frequency, increase the stiffness value of the built-in buffer block 1; if the suspension natural frequency is greater than the set target value of the full-load natural frequency, reduce the stiffness value of the built-in buffer block 1; when the suspension natural frequency meets the set target value of the full-load natural frequency, extract the relationship curve between wheel hop and the force on the built-in buffer block 1 in the post-processing module, and read the force value of the built-in buffer block 1 when the full-load wheel hop occurs, and read the buffer block compression amount L1 at this force value.

[0039] S11: Calculate the wheel center load at the handling and stability limit travel and the wheel center load at the wheel hop limit travel; Among them, the wheel center load at the handling and stability limit travel: FL2g = M * g; The wheel center load at the wheel hop limit travel: FL5g = 5 * (M_full - m) * g / 2; S12: Conduct a parallel wheel hop condition simulation analysis on the suspension dynamics model under the condition of the clearance of the built-in buffer block 1 confirmed in step S9, and establish the relationship curve between wheel hop travel and wheel center load; S13: Through the calculated wheel center load at the handling and stability limit travel, read the wheel hop travel at the wheel center load at the handling and stability limit travel on the relationship curve between wheel hop travel and wheel center load, that is, the 2G wheel hop travel; S14: Compare the 2G wheel hop stroke with the set handling and ride limit stroke target value; S15: Does the 2G wheel hop stroke meet the set handling and ride limit stroke target value? If yes, execute step S18; If no, when the 2G wheel hop stroke is greater than the set handling and ride limit stroke target value, execute step S16; when the 2G wheel hop stroke is less than the set handling and ride limit stroke target value, execute step S17; S16: Modify the property file of the external buffer block 2 to increase the buffer block stiffness; perform a parallel wheel hop condition simulation analysis on the suspension dynamic model again, and execute step S13; S17: Modify the property file of the external buffer block 2 to decrease the buffer block stiffness; perform a parallel wheel hop condition simulation analysis on the suspension dynamic model again, and execute step S13; S18: Confirm the stiffness of the external buffer block 2; execute step S19; S19: Read the relationship curve between the wheel hop stroke and the buffer block force, and confirm the force value of the external buffer block 2 when passing through the 2G wheel hop stroke; S20: In the property file of the external buffer block 2, determine the compression amount L1 of the buffer block based on the force value of the external buffer block 2 when passing through the 2G wheel hop stroke; among them, the stiffness of the external buffer block 2 confirmed in step S18 is the buffer block stiffness above the compression amount L1 of the external buffer block 2; S21: Perform a parallel wheel hop condition simulation analysis on the suspension dynamic model again under the condition of meeting the clearance of the internal buffer block 1 confirmed in step S9 and the stiffness of the external buffer block 2 confirmed in step S18, and establish a relationship curve between the wheel hop stroke and the wheel center load; S22: Through the wheel center load of the calculated wheel hop limit stroke, read the wheel hop stroke under the wheel center load of the wheel hop limit stroke on the relationship curve between the wheel hop stroke and the wheel center load, that is, the 5G wheel hop stroke; S23: Compare the 5G wheel hop stroke with the set wheel hop limit stroke target value; S24: Does the 5G wheel hop stroke meet the set wheel hop limit stroke target value? If yes, execute step S27; If no, when the 5G wheel hop stroke is greater than the set wheel hop limit stroke target value, execute step S25; when the 5G wheel hop stroke is less than the set wheel hop limit stroke target value, execute step S26; S25: Modify the property file of the external buffer block 2 to only increase the stiffness of the external buffer block 2; perform a parallel wheel hop condition simulation analysis on the suspension dynamic model again, and execute step S22; S26: Modify the property file of the external buffer block 2 to only reduce the stiffness of the external buffer block 2; conduct a parallel wheel hop condition simulation analysis on the suspension dynamic model again, and execute step S22; S27: Confirm the buffer block stiffness after the adjustment of the external buffer block 2; S28: Output the clearance calculated in step S10 and the buffer block stiffness confirmed in S18 and S27.

[0040] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A design method for the gap and stiffness of internal and external buffer blocks of a new type of automotive suspension, characterized in that, The built-in buffer block is placed inside the spring, and the external buffer block is used to limit the extreme stroke of the suspension. The steps include: Establish a suspension dynamics model; Conduct a parallel wheel hop simulation analysis on the suspension dynamics model to make the wheel hop stroke at the initial contact of the built-in buffer block meet the set contact clearance stroke target value; Extract the relationship curve between wheel hop and wheel load in the post-processing module, calculate the suspension stiffness and full-load natural frequency, determine the wheel center loads of the handling and stability extreme stroke and the wheel hop extreme stroke, adjust the stiffness of the built-in buffer block to make the suspension natural frequency meet the set full-load natural frequency target value, and record the compression amount L1 of the built-in buffer block at full load; Based on the wheel center load F at the handling and stability limit travel L2g Adjust the stiffness of the built-in buffer block above the compression amount L1 so that the wheel jump travel of operation 2G meets the set handling and stability limit travel target value; Perform secondary calibration on the external buffer block clearance to make the wheel hop stroke at the contact of the external buffer block consistent with the handling and stability extreme stroke target value; Axle center load F based on the limit stroke of wheel hop L5g Adjust the stiffness of the internal and external buffer blocks so that the wheel hop stroke of the operation 5G meets the set target value of the limit stroke of wheel hop; Output the built-in buffer block clearance and stiffness, and the external buffer block clearance and stiffness parameters that meet the targets.

2. The method for designing the clearance and stiffness of the internal and external buffer blocks of the new car suspension according to claim 1, characterized in that, The establishment of the suspension dynamics model includes: Obtain the suspension type of the vehicle model and interpret the structures of the suspension system and the steering system; Extract the hard points in the digital model; Establish the suspension system, steering system, and anti-roll bar templates in the Template of Adams / car; In the standard mode of Adams / car, use the templates established in the Template to establish the subsystems of the suspension, steering, and anti-roll bar; Assemble each subsystem into an assembly; Input the extracted hard points into the assembly, write the property files of each component, and assign them to the assembly to generate a complete suspension dynamics model.

3. The novel design method for the gap and stiffness of the internal and external buffer blocks of an automotive suspension according to claim 1, characterized in that, Before the steps of establishing the suspension dynamics model include: Set the contact clearance stroke target value, full-load natural frequency target value, handling and stability extreme stroke target value, and wheel hop extreme stroke target value according to the vehicle performance.

4. The novel design method for the gap and stiffness of the internal and external buffer blocks of an automotive suspension according to claim 1, characterized in that, The conduct of the parallel wheel hop simulation analysis on the suspension dynamics model to make the wheel hop stroke meet the contact clearance stroke target value includes: Adjust the external buffer block clearance value; Input the initial clearance value to conduct a parallel wheel hop simulation analysis on the established suspension dynamics model, and extract the relationship curve between wheel hop and buffer block force in the post-processing module; Read the wheel hop stroke when the buffer block just receives force, that is, the wheel hop stroke when contacting the buffer block; Compare the wheel hop stroke when contacting the buffer block with the set contact clearance stroke target value; If the wheel hop stroke when contacting the buffer block is greater than the set contact clearance stroke target value, reduce the clearance value in the suspension dynamics model; If the wheel hop stroke when contacting the buffer block is less than the set contact clearance stroke target value, increase the clearance value in the suspension dynamics model; When the wheel hop stroke when contacting the buffer block meets the set contact clearance stroke target value, confirm the clearance value in the suspension dynamics model as the buffer block clearance.

5. The novel design method for the clearance and stiffness of the internal and external buffer blocks of an automotive suspension according to claim 1, characterized in that, The suspension stiffness is determined by the slope of the wheel load relationship curve within the range of ±5 mm of the wheel hop amount at full load, where Wheel load at full load: F_full = M_fullg / 2; Suspension natural frequency: ; K is the suspension stiffness, and M 满簧上 is the unsprung mass when fully loaded.

6. The method for designing the gap and stiffness of the internal and external buffer blocks of the new automobile suspension according to claim 1, characterized in that, The adjustment of the built-in buffer block stiffness to make the suspension natural frequency meet the set full-load natural frequency target value and record the compression amount L1 of the buffer block at full load includes: If the suspension natural frequency is less than the set full-load natural frequency target value, increase the built-in buffer block stiffness value; If the suspension natural frequency is greater than the set full-load natural frequency target value, reduce the built-in buffer block stiffness value; When the suspension partial frequency meets the set full-load partial frequency target value, the post-processing module extracts the relationship curve between the wheel hop and the force on the built-in buffer block, reads the force value of the built-in buffer block when the full-load wheel hop occurs, and reads the buffer block compression amount L1 at this force value.

7. The novel design method for the gap and stiffness of the internal and external buffer blocks of an automotive suspension according to claim 1, characterized in that, The wheel center load F based on the handling and stability limit stroke L2g Adjust the stiffness of the built-in buffer block above the compression amount L1 so that the wheel hop stroke of the handling and stability 2G meets the set handling and stability limit stroke target value; previously included: Calculate the wheel center load of the handling and stability limit stroke and the wheel center load of the wheel hop limit stroke; Among them, the wheel center load at the handling and stability limit stroke: F L2g = M * g; Axle load at the extreme travel of the wheel jump: F L5g = 5 * (M full - m) * g / 2; F L2g : Wheel center load at the extreme stroke of handling and stability F L5g : Wheel center load at the limit travel of the wheel jump M: The mass of the front axle or rear axle at half load; M full: The mass of the front axle or rear axle at full load; m: The unsprung mass of the front axle or rear axle; g: The acceleration due to gravity.

8. The novel design method for the gap and stiffness of the internal and external buffer blocks of an automotive suspension according to claim 1, characterized in that, The wheel center load F based on the handling and stability limit stroke L2g Adjust the stiffness of the built-in buffer block above the compression amount L1 so that the wheel hop stroke of the handling 2G meets the set handling and stability limit stroke target value, including: Perform a parallel wheel hop condition simulation analysis on the suspension dynamic model under the condition of satisfying the buffer block clearance, and establish a relationship curve between the wheel hop stroke and the wheel center load; Based on the calculated wheel center load of the handling and stability limit stroke, read the wheel hop stroke at the wheel center load of the handling and stability limit stroke on the relationship curve between the wheel hop stroke and the wheel center load, that is, the 2G wheel hop stroke; Compare the 2G wheel hop stroke with the set handling and stability limit stroke target value; If the 2G wheel hop stroke is greater than the set handling and stability limit stroke target value, modify the buffer block property file to increase the stiffness above the buffer block compression amount L1; If the 2G wheel hop stroke is less than the set handling and stability limit stroke target value, modify the buffer block property file to decrease the stiffness above the buffer block compression amount L1; When the 2G wheel hop stroke meets the handling and stability limit stroke target value, confirm the buffer block stiffness.

9. The novel design method for the gap and stiffness of the internal and external buffer blocks of an automotive suspension according to claim 1, characterized in that, The secondary calibration of the external buffer block clearance makes the wheel hop stroke when the external buffer block contacts consistent with the handling and stability limit stroke target value; including: Under the condition of satisfying the buffer block stiffness, adjust the external buffer block clearance, and then perform a parallel wheel hop condition simulation analysis on the suspension dynamic model to establish a relationship curve between the wheel hop stroke and the force on the external buffer block; Read the wheel hop stroke when the external buffer block is stressed. If the wheel hop amount at this time is greater than the set handling and stability limit stroke target value, decrease the external buffer block clearance value; If the wheel hop amount at this time is less than the set handling and stability limit stroke target value, increase the external buffer block clearance value; When the wheel hop stroke of the external buffer block meets the handling and stability limit stroke target value, confirm the clearance of the external buffer block.

10. The novel design method for the gap and stiffness of the internal and external buffer blocks of an automotive suspension according to claim 1, characterized in that, The wheel center load F based on the limit stroke of the wheel hop L5g Adjust the stiffness of the internal and external buffer blocks to make the wheel hop stroke of the operation 5G meet the set target value of the limit stroke of the wheel hop, including: Perform a parallel wheel hop condition simulation analysis on the suspension dynamic model again under the condition of satisfying the buffer block clearance and the confirmed buffer block stiffness, and establish a relationship curve between the wheel hop stroke and the wheel center load; Based on the calculated wheel center load of the wheel hop limit stroke, read the wheel hop stroke at the wheel center load of the wheel hop limit stroke on the relationship curve between the wheel hop stroke and the wheel center load, that is, the 5G wheel hop stroke; Compare the 5G wheel hop stroke with the set wheel hop limit stroke target value; If the 5G wheel hop stroke is greater than the set wheel hop limit stroke target value, modify the buffer block property file to only increase the stiffness of the buffer block; If the 5G wheel hop stroke is less than the set wheel hop limit stroke target value, modify the buffer block property file to only decrease the stiffness of the buffer block; When the 5G wheel hop stroke meets the wheel hop limit stroke target value, confirm the buffer block stiffness after adjustment of the buffer block.

Images