CN111400818B - Method for determining connection point of non-bearing type electric automobile frame, non-bearing type electric automobile frame and electric automobile - Google Patents

Method for determining connection point of non-bearing type electric automobile frame, non-bearing type electric automobile frame and electric automobile Download PDF

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Publication number
CN111400818B
CN111400818B CN201811645878.5A CN201811645878A CN111400818B CN 111400818 B CN111400818 B CN 111400818B CN 201811645878 A CN201811645878 A CN 201811645878A CN 111400818 B CN111400818 B CN 111400818B
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frame
vehicle
connection point
modal
determining
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CN111400818A (en
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穆峰
孙喜冬
张葆华
甄林涛
孙志伟
许占高
李子新
邢俊涛
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Great Wall Motor Co Ltd
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Great Wall Motor Co Ltd
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60KARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES
    • B60K1/00Arrangement or mounting of electrical propulsion units
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60KARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES
    • B60K1/00Arrangement or mounting of electrical propulsion units
    • B60K1/04Arrangement or mounting of electrical propulsion units of the electric storage means for propulsion
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B62LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62DMOTOR VEHICLES; TRAILERS
    • B62D24/00Connections between vehicle body and vehicle frame
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B62LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62DMOTOR VEHICLES; TRAILERS
    • B62D24/00Connections between vehicle body and vehicle frame
    • B62D24/02Vehicle body, not intended to move relatively to the vehicle frame, and mounted on vibration absorbing mountings, e.g. rubber pads

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Transportation (AREA)
  • Mechanical Engineering (AREA)
  • Body Structure For Vehicles (AREA)

Abstract

The invention provides a method for determining a frame connection point of a non-bearing electric automobile, which is used for determining the position of a frame body connection point on a frame and comprises the steps of establishing a three-dimensional model of a frame structure; importing the established three-dimensional model into finite element processing software to carry out finite element gridding processing and output a grid file; importing the grid file into simulation software, defining a simulation frequency interval, and simulating a frame modal graph under each order of frequency; and counting the vehicle frame modal values in each order of vehicle frame modal graphs, and taking the position with the maximum low modal contact ratio in each region in different order modal graphs as the position of the connecting point. The invention also provides a non-bearing type automobile frame and an automobile, wherein the connection point is determined by the determination method. The connection point position determined by the determination method of the invention can realize the large rigid connection between the frame and the vehicle body, realize the strength complementation of the frame and the vehicle body, and the frame and the vehicle body can bear the stress as a whole, thereby being beneficial to realizing the weight reduction design of the whole vehicle.

Description

Method for determining connection point of non-bearing type electric automobile frame, non-bearing type electric automobile frame and electric automobile
Technical Field
The invention relates to the technical field of vehicle design and development, in particular to a method for determining a frame connection point of a non-bearing electric vehicle. The invention also relates to a non-bearing type automobile frame for determining the position of the connecting point by the determination method and a non-bearing type automobile with the frame.
Background
In the prior art, the structure of the automobile body is mainly divided into a bearing type body and a non-bearing type body. The load-bearing type vehicle body does not have a chassis structure which can bear external force independently, and only supports all parts by the vehicle body, namely the whole vehicle body is used as a whole without an independent girder design, the vehicle body is mounted on the vehicle body through an auxiliary frame in a hanging mode, and the load of the vehicle body is transmitted to wheels through a hanging device. The load-bearing type vehicle body structure has the advantages of small weight, high vehicle stability, low cost, light weight, low oil consumption, good comfort and the like, but the non-load-bearing type vehicle body structure also has the defects of poor vehicle body rigidity, particularly poor diagonal distortion resistance rigidity and the like.
The non-bearing body is also called as a chassis girder frame, which has an independent girder, namely a frame, and has a special chassis stress structure, and core components such as an engine, a transmission and the like are arranged on the frame. The frame as a whole is a foundation for supporting the whole vehicle, and the body part for the whole person to sit on is another whole on the whole structure. The frame and the upper vehicle body are mainly connected by suspension, the chassis is lower, the vehicle body part is upper, and the vehicle body only bears the weight of drivers and passengers without considering the auxiliary effect of the vehicle body on the frame bearing.
The non-bearing type vehicle body has the advantages of independent vehicle frame, high chassis strength, good anti-bumping performance, non-uniform stress of the four wheels, and no transmission to the vehicle body, so the deformation of the carriage is small, the stability and the safety are good, and the noise in the carriage is low. However, the non-load-bearing type vehicle body structure also has the defects of being heavy, high in mass center of the vehicle and poor in high-speed running stability, particularly the heavy weight of the vehicle body structure causes higher cost of the whole vehicle, and the fuel consumption of the vehicle is always high when the vehicle is used.
With the continuous development of the electrification technology and the gradual shortage of petroleum resources, electric vehicles gradually move to the lives of people and are accepted by more and more people, and with the improvement of the living standard of people in China, vehicle types with good space, stability and safety, such as SUV (sports utility vehicle) vehicle types, are enjoyed by more and more people, so that the electric SUV vehicle types are quietly popular products in the domestic automobile market.
For an electric vehicle, an important standard for measuring the quality of the electric vehicle is the duration of the endurance mileage, and if the electric vehicle wants to obtain a higher endurance mileage, a very important means for pursuing light weight by weight reduction design is not negligible. At this time, for a non-load-bearing electric vehicle model with a frame structure, if a relatively high rigid connection between the frame and the vehicle body can be performed, so that the connection rigidity between the frame and the vehicle body is improved, the strength complementation between the frame and the vehicle body is realized, and the characteristic similar to the load-bearing vehicle body structure is achieved, so that a relatively good whole vehicle weight reduction effect can be obtained.
However, at present, aiming at the connection with great rigidity between the frame and the vehicle body, how to determine the position of the connecting point of the connection between the frame and the vehicle body becomes a difficult problem, and no report related to the connection is found in the published documents.
Disclosure of Invention
In view of the above, the present invention is directed to a method for determining a connection point of a frame of a non-load-bearing electric vehicle, so as to determine a connection point position on the frame, where a connection with a vehicle body with high rigidity is performed.
In order to achieve the purpose, the technical scheme of the invention is realized as follows:
a method for determining the connection points of a non-bearing electric vehicle frame is used for determining the positions of the connection points for connecting the frame and a vehicle body on the frame, motors are arranged at the front end and the rear end of the frame to less than the rear end of the frame, a battery pack is fixedly arranged in the middle of the frame, the connection points on the frame are distributed in different areas of the frame in a scattered manner, and the method for determining the positions of the connection points comprises the following steps:
s1, establishing a three-dimensional model of a frame structure according to a development design target of a whole vehicle;
s2, importing the established three-dimensional model of the frame structure into finite element processing software, carrying out finite element meshing processing on a three-dimensional model file of the frame structure by using the finite element processing software, and outputting a meshed grid file;
s3, importing the grid file output in the step S2 into modal simulation software, defining a simulation frequency interval, simulating the frame mode of the frame model under each order frequency in the frequency interval by using the modal simulation software, and outputting a frame mode graph under each order frequency;
and S4, counting modal values of all positions on the frame in the frame modal graph corresponding to each order frequency, and taking the position with the maximum low modal contact ratio in each region in the frame modal graph under different order frequencies as the position of a connecting point between the frame and the vehicle body in the region.
Further, the frame structure three-dimensional model can be established through CATIA, UG or Pro/E, the finite element processing software is ANSA or HypermeSh, and the simulation software is NASTRAN or ABAQUS.
Further, the frequency interval is from 1HZ to the natural frequency of the motor carried by the frame.
Further, the positions of the body connecting points of each frame on the frame are symmetrically arranged relative to the width center line of the frame.
Further, in step S4, the position of the vehicle body connection point is the position where the mode nodes in the area overlap most.
Further, the finite element meshing processing in step S2 includes the steps of:
s21, removing redundant geometric figures including points, lines and round corners;
s22, performing a median plane drawing operation, and performing grid division on the median plane;
s23, creating a gridding partition file and a quality inspection file to generate a gridding, inspecting gridding quality, correcting errors and correcting a gridding with poor quality;
s24, separating the grid from the geometric model, deleting the originally imported frame structure model file, creating a welding unit and a rigid node, defining the material thickness and the material properties including the elastic modulus E, the NU Poisson' S ratio and the RHO density, and exporting the grid file.
Further, the simulation in step S3 includes the following steps:
s31, establishing a frame model generated by selecting and importing the attributes of the frame model, and defining the thickness of a material;
s32, giving the material attribute and the material thickness to the frame model;
s33, creating a simulation environment, and defining a simulation frequency interval;
and S34, the ND calculates the order in the frequency interval, a control guidance calculation link solver is established to carry out corresponding calculation commands, and a simulated vehicle frame modal diagram is derived.
Furthermore, the area of the frame, which can be used as the connecting point between the frame and the vehicle body, at least meets the following conditions: easily the frame shaping does not influence the automobile body molding does benefit to the frame with assemble between the automobile body to and accord with the motorcycle type function definition.
Further, the vehicle type function definition comprises that the vehicle type function is a passenger vehicle or a goods vehicle.
Compared with the prior art, the invention has the following advantages:
the frame connection point determining method is based on the characteristic of small motor vibration, the frame model is simulated, and the position with the largest low-modal contact ratio in each region is used as the connection point position, so that the weakest point of vibration superposition in each region of the frame can be used as the connection point between the frame and the vehicle body, and the large-rigidity connection between the frame and the vehicle body can be performed due to the weak vibration of the connection point, so that the strength complementation between the frame and the vehicle body is realized, the integral bearing stress of the frame and the vehicle body is realized, and the effect of the weight reduction design of the whole vehicle is favorably realized.
Another objective of the present invention is to provide a non-load-bearing type vehicle frame, wherein at least the rear end of the front end and the rear end of the frame is provided with a motor, the middle of the frame is fixedly provided with a battery pack, and the frame is provided with a plurality of connectors for connecting with a vehicle body, the connectors are located at the positions of the connection points between the frame and the vehicle body determined by the above determination method, and the connectors are elastic connectors or rigid connectors.
Further, the elastic connecting piece is suspended.
According to the non-bearing type electric automobile frame, the connecting piece is arranged at the connecting point position determined by the determination method, so that high-rigidity connection between the frame and the automobile body can be realized, the strength between the frame and the automobile body is complementary, the frame and the automobile body can bear stress as a whole, and the whole automobile is lightened.
In addition, the invention also provides a non-bearing type automobile which is provided with the non-bearing type automobile frame.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention, illustrate embodiments of the invention and together with the description serve to explain the invention and do not constitute a limitation of the invention. In the drawings:
FIG. 1 is a schematic structural view of a vehicle frame according to an embodiment of the present invention;
FIG. 2 is a schematic structural view of the front end of the frame according to the embodiment of the present invention;
FIG. 3 is a schematic structural view of the front end of the frame according to the embodiment of the present invention;
FIG. 4 is a schematic structural view of a center portion of the vehicle frame according to an embodiment of the present invention;
FIG. 5 is a schematic structural view of the rear end of the frame in accordance with an embodiment of the present invention;
in the figure:
1-front end structure, 2-middle structure, 3-back end structure;
101-longitudinal beam, 102-front shock absorber tower, 103-collapse beam, 104-anti-collision beam assembly, 105-water tank mounting frame, 106-supporting beam, 107-shock absorber tower reinforcing bracket, 108-front cross beam, 109-front bottom guard plate, 1010-supporting side beam, 1011-reinforcing beam, 1012-suspension mounting seat and 1013-front motor mounting bracket;
201-battery pack;
301-rear shock absorber tower, 302-rear cross beam, 303-tower top support frame, 304-rear motor mounting bracket, 305-rear anti-collision beam, 306-reinforcing rod, 307-rear bottom guard plate.
Detailed Description
It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict.
Example one
The embodiment relates to a method for determining a frame connection point of a non-bearing electric vehicle, which is used for determining the position of a connection point for connecting a frame and a vehicle body on the frame in the non-bearing electric vehicle. The vehicle body structure comprises a vehicle frame, a battery pack, a plurality of connection points, a plurality of connecting points and a plurality of connecting pieces, wherein the vehicle frame is provided with a front end and a rear end, the front end and the rear end of the vehicle frame are respectively provided with a motor, the middle of the vehicle frame is fixedly provided with the battery pack, the connection points are arranged on the vehicle frame and are used for connecting the vehicle frame with a vehicle body in a distributed mode in different areas of the vehicle frame, stable and reliable connection between the vehicle frame and the vehicle body can be achieved through connection in a plurality of different positions, and then a complete vehicle body structure is formed.
As for the frame structure of the electric vehicle of the present embodiment, an exemplary structure is shown in fig. 1, and the frame structure integrally includes three parts, namely a front end structure 1, a middle structure 2 and a rear end structure 3, the motors 4 respectively disposed at two ends are respectively located in the front end structure 1 and the rear end structure 3, and the battery pack belongs to a part of the middle structure 2. It should be noted that, except for the front end structure 1 and the rear end structure 3, it is needless to say that the motors may be provided only at the rear end, and the following method for determining the positions of the frame connection points is the same.
Specifically, as shown in fig. 2 and 3 in combination, the front end structure 1 of the vehicle frame of the present embodiment includes side members 101 on both sides, a front shock absorber mounting tower 102 fixedly connected to each side member 101, and a crash beam assembly 104 connected between front ends of the side members 101 on both sides, a water tank mounting bracket 105 for mounting and fixing a water tank of a vehicle located on a rear side of the crash beam assembly 104, and a front cross member 108 disposed below the water tank mounting bracket 105 and connected between the side members 101 on both sides.
Wherein, the crashproof roof beam assembly 104 can be connected with the end of longeron 101 through water tank mounting bracket 105, and crashproof roof beam assembly 104 also preferably adopts two crashproof roof beam bodies that arrange from top to bottom to obtain corresponding to the good protection under the high low-speed collision. A crush beam 103 is further provided between the tank mounting bracket 105 and the front absorber tower 102 corresponding to the upper impact beam body, a suspension mount 1012 is provided on the other side of the front absorber tower 102 with respect to the crush beam 103, and the force transmission of the crush beam 103 to the side member 101 is realized by the front absorber tower 102 and the suspension mount 1012.
In the front end structure 1 of this embodiment, a supporting edge beam 1010 is further connected between the two ends of the top of the tank mounting bracket 105 and the front absorber towers 102 on the two sides, and a reinforcing beam 1011 is also provided on the inner side of the supporting edge beam 1010 on the two sides and connected between the tank mounting bracket 105 and the front absorber towers 102 on the two sides, and the stability of the tank mounting bracket 105 can be improved by the reinforcing beam 1011. In this embodiment, in order to improve the stability of the arrangement of the two side front absorber towers 102 and improve the structural rigidity of the two side front absorber towers, a absorber tower reinforcing bracket 107 is connected between the tops of the two front absorber towers 102, and a supporting beam 106 is also connected near the bottoms of the two side front absorber towers 102.
In this embodiment, the front motor mounting brackets 1013 are also fixedly connected to the suspension mounting seats 1012 on the two sides, and the motor 4 at the front end structure 1 is fixedly connected between the front motor mounting brackets 1013 on the two sides, so as to directly and fixedly connect with the side stringers 101 on the two sides. Further, a front floor panel 109 fixed to the front cross member 108 is provided between the side members 101 on both sides at the bottom of the front end structure 1. Suspension connecting brackets for connecting swing arms and the like in the front suspension are also arranged on the longitudinal beam 101, and the structure and the arrangement of the suspension connecting brackets can be found in the existing Macpherson suspension arrangement mode, so that the detailed description is omitted.
The middle structure 2 in the frame of the present embodiment specifically includes the longitudinal beams 101 on both sides, and further includes a battery pack 201 directly fixed between the longitudinal beams 101 on both sides, as shown in fig. 4. The battery pack 201 is integrally composed of a bottom case and a cover plate covering the bottom case, the longitudinal beams 101 which are specifically connected with the upper and lower sides of the bottom case can be connected with the bottom case through bolts, and a battery module, a battery management module and a cooling module are arranged in the bottom case, and the battery module, the electric field management module and the cooling module can be realized by referring to related structures in a power battery in the existing electric automobile.
In order to improve the structural strength of the middle structure 2 and to have better longitudinal force transmission performance and side impact performance, in this embodiment, the longitudinal beam 101 at the middle structure 2 has a straight beam body, and a partition arranged along the transverse direction of the vehicle frame is constructed in the bottom case in the battery pack 201, and two ends of the partition extend to two ends of the width direction of the bottom case so as to be connected with the longitudinal beam 101 through the edge portion of the bottom case, so that a reinforcing rib structure between the longitudinal beams 101 at two sides can be formed. In addition, in terms of arrangement, in this embodiment, the bolts for connecting the bottom case and the longitudinal beam 101 may be arranged corresponding to the end portions of the partitions, that is, the bolts are located on the extension lines of the partitions, so that the purpose of connecting strength between the battery pack 201 and the longitudinal beam 101 can also be achieved.
The rear end structure 3 of the present embodiment is specifically shown in fig. 5, and specifically includes longitudinal beams 101 on both sides, a rear absorber tower 301 connected to the longitudinal beams 101 on both sides, respectively, and a rear cross member 302 and a rear impact beam 305 connected between the longitudinal beams 101 on both sides. In order to improve the structural strength of the rear shock absorber tower 301, a tower top support frame 303 is also arranged on one side of the rear shock absorber tower 301, the tower top support frame 303 is connected between the rear shock absorber tower 301 and the longitudinal beams 101, rear motor mounting brackets 304 are fixedly connected to the tower top support frames 303 on the two sides respectively, and the motor 4 in the rear end structure 3 is connected between the rear motor mounting brackets 304 on the two sides so as to be directly and fixedly connected with the longitudinal beams 101 on the two sides.
In the rear end structure 3, a reinforcing bar 306 is provided behind the rear cross member 302 in a cross arrangement, and a rear floor panel 307 is also fixed to the rear cross member 302. In this embodiment, rear suspension mounting brackets are also disposed on the longitudinal beams 101 on both sides of the rear end structure 3, the rear shock absorber tower 301 and the tower top support frame 304, and the arrangement and structure of these rear suspension mounting brackets can refer to the existing five-link independent suspension structure, which is not described herein again.
Based on the above description of the frame structure, the method for determining the location of the connection point in the present embodiment includes the following steps as a whole. Before the following connection point position determining steps are introduced, it should be noted that the establishment of the three-dimensional model of the frame structure can be performed through CATIA, UG or Pro/E, the operation of finite element meshing can be performed through ANSA or HyperMeSh, and the modal simulation can be performed through NASTRAN or ABAQUS. In the embodiment, the whole determination method is described by specifically adopting CATIA modeling, ANSA for finite element meshing and NASTRAN for frame modal simulation as an example.
The method for determining the position of the connection point in the embodiment specifically comprises the following steps:
s1, modeling: according to the development and design target of the whole vehicle, a vehicle frame structure model is established through CATIA software, namely a three-dimensional model diagram of a vehicle frame is drawn, and the established vehicle frame structure model is output as a vehicle frame structure model file in Stp format;
step S2, gridding treatment step: importing the frame structure model file in Stp format exported in the step S1 into ANSA software, carrying out finite element gridding processing on the imported frame model file by using the ANSA software, and outputting a gridding processed grid file;
s3, simulation: importing the grid file output in the step S2 into NASTRAN software, defining a simulation frequency interval, simulating the frame mode of the frame model at each order frequency in the frequency interval by using the NASTRAN software, and outputting a frame mode graph at each order frequency;
s4, analyzing and determining: and counting modal values of each position on the frame in the frame modal diagram corresponding to each order frequency output by NASTRAN software, and taking the position with the maximum low-modal contact ratio in each area in the frame modal diagram under different order frequencies as the position of the connection point between the frame and the body in the area, thereby obtaining the positions of the connection point between the frame and the body in different areas on the whole frame.
For the above determining steps, in detail, the basic architecture of the vehicle model determined after the vehicle model pre-research is completed, the design objectives of each part and assembly, and the structural parameters based on the objectives, the architecture and each parameter can realize the establishment of the three-dimensional digifax of the vehicle frame.
The finite element meshing process in step S2 specifically includes the following steps.
Step S21: removing redundant geometric figures containing points, lines and round corners;
step S22: performing a drawing operation on the middle surface, and performing mesh division on the middle surface;
step S23: creating a gridding division file and a quality inspection file to generate a gridding, and inspecting the quality of the gridding, correcting errors and poor-quality gridding;
step S24: separating the grid from the geometric model, deleting the originally imported frame structure model file, creating a welding unit and a rigid node, defining the material thickness and the material properties including the elastic modulus E, the NU Poisson ratio and the RHO density, and then exporting the processed grid file.
The frame model file after finite element gridding processing is obtained through the step-by-step execution of the steps, and then the frame model file can be introduced into NASTRAN software for modal simulation. In this case, for the simulation process in step S3, it should be noted that the frequency range defined in the simulation is specifically 1HZ to the natural frequency of the motor carried on the vehicle frame. The starting frequency 1HZ here is the frequency of the occupants of the automobile, i.e. the frequency of the human body is generally 1-1.6HZ, so the simulation of the frame mode is performed starting from 1 HZ.
In addition, the simulation process of step S3 in this embodiment also includes the following steps.
Step S31: creating a frame model generated by a grid file with imported attribute selection, and defining the thickness of a material;
step S32: giving the material attribute and the material thickness to the frame model;
step S33: creating a simulation environment and defining a simulation frequency interval;
step S34: and the ND calculates the orders in the frequency interval, creates a control guidance calculation link solver to carry out corresponding calculation commands, and derives simulated vehicle frame modal diagrams corresponding to the frequencies of each order, namely first order, second order to N order.
After the vehicle frame modal diagrams under each order of frequency are simulated and output through NASTRAN software, statistical analysis of each order of modal diagrams can be executed so as to determine the positions of the connection points in each area. Specifically, taking a certain region as an example, the modal values at various positions in the region may be different at different step frequencies, or at least different modal quantities may be present at some step frequencies, so the modal values at all positions in the region are collected and counted, and the modal images of the steps are compared with each other, so that the position with the highest low modal coincidence degree in the same region in all step modal images can be obtained, and the position is also the connecting point position used as the connection between the frame and the vehicle body in the region.
In this embodiment, as a further supplementary explanation to step S4, for the above-mentioned limitation that the position with the highest degree of overlap of the low mode is taken as the position of the connecting point of the frame and the vehicle body, as an optimal mode contained therein, the mode node in the region, that is, the position where the points with the mode shape coefficient of zero overlap most, can be set and selected as the position of the connecting point, and at this time, the connecting point is determined to be the position where the nodes overlap most, so that a better frame and vehicle body connecting effect can be obtained.
In addition to the above-mentioned specific steps of modeling, gridding, simulation, and statistical analysis to determine the positions of the connection points, it should be considered that the positions of the connection points between the vehicle frame and the vehicle body, which are determined on the vehicle frame, should preferably be symmetrically arranged with respect to the center line of the width of the vehicle frame. Furthermore, the selection of the aforementioned region of the frame where the connection point can be arranged should also satisfy at least the following conditions: easily the frame shaping does not influence the automobile body molding does benefit to the frame with assemble between the automobile body to and accord with the motorcycle type function definition.
The vehicle type function definition includes a passenger vehicle or a cargo vehicle, and the vehicle type function definition is considered because the connection point positions corresponding to different vehicle types and the number of the connection points are different. For example, in the case of passenger cars, since the passenger cars are more comfortable, less vibration and noise of the lower car body are transmitted to the engine room, and the connection points on the frame should be of a resilient structure such as suspension, and the number of connection points is as large as possible. For cargo vehicles, such as pick-up trucks, the rear cargo box requires stability due to the major consideration of load-carrying factors, and the comfort requirement is low, so the attachment points for the rear cargo box portion of the pick-up truck can be directly rigidly attached, such as by bolts, and the attachment points can be selected according to the load-carrying capacity design.
In addition, it should be noted that, in the embodiment, the selection of the areas for arranging the connection points on the frame based on the conditions of easy forming of the frame, no influence on the shape of the vehicle body, convenient assembly between the frame and the vehicle body, and conformity with the vehicle type function definition is not necessary for determining the positions of the connection points between the frame and the vehicle body, that is, when determining the positions of the connection points, the areas can be arbitrarily specified without considering the above conditions, and the connection point positions of different areas can be finally found by the determination step.
However, it is necessary to preliminarily select an area suitable for arranging the connection point on the vehicle frame through the above conditions, and finally determine a suitable connection point in the determination step combined with the present embodiment, in view of not affecting the vehicle frame structure, not affecting the vehicle body shape, contributing to the improvement of the convenience of the vehicle body and the vehicle frame connection, and effectively reducing the influence of the excitation source on the engine room.
In this embodiment, the positions of the connection points determined on the frame through the above determining steps may be as shown by D1-D8 in fig. 1. After determining the positions of the connection points through the determining step of the embodiment, the connection between the vehicle frame and the vehicle body can be performed through an elastic connection structure such as a suspension or a rigid connection structure such as a bolt according to different vehicle types. The connecting points of all the areas are low-modal or node positions of the frame, so that the weakest point of vibration superposition in all the areas of the frame can be used as the connecting point between the frame and the body, the weak vibration of the connecting point can realize high-rigidity connection between the frame and the body, the strength complementation of the frame and the body is realized, the integral bearing stress of the frame and the body can be realized, and the effect of weight reduction design of the whole vehicle is favorably realized.
Example two
The present embodiment relates to a non-load-bearing type vehicle frame, wherein a plurality of connecting members for connecting with a vehicle body are installed on the vehicle frame, each connecting member is located at a connecting point between the vehicle frame and the vehicle body determined by the determining method of the first embodiment, and the connecting members are elastic connecting members or rigid connecting members, and when the elastic connecting members are selected, the elastic connecting members are preferably suspended.
The embodiment also relates to a non-bearing type automobile, and the non-bearing type automobile frame is arranged on the non-bearing type automobile.
The non-load-bearing electric vehicle frame and the electric vehicle of the embodiment can realize high-rigidity connection between the frame and the vehicle body by arranging the connecting piece at the connecting point position determined by the determination method in the first embodiment, so that the strength between the frame and the vehicle body is complementary, the frame and the vehicle body can bear stress as a whole, the weight of the whole vehicle is reduced, and the non-load-bearing electric vehicle frame and the electric vehicle have good practicability.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Claims (12)

1. A method for determining a connection point of a frame of a non-bearing electric vehicle is used for determining the position of a connection point for connecting the frame and a vehicle body on the frame, and is characterized in that: the motor is arranged at least at the rear end of the front end and the rear end of the frame, the battery pack is fixedly arranged in the middle of the frame, the connection points on the frame are a plurality of connection points which are dispersedly arranged in different areas of the frame, and the determination method of the positions of the connection points comprises the following steps:
s1, establishing a three-dimensional model of a frame structure according to a development design target of a whole vehicle;
s2, importing the established three-dimensional model of the frame structure into finite element processing software, carrying out finite element gridding processing on the three-dimensional model file of the frame structure by using the finite element processing software, and outputting a gridding processed gridding file;
s3, importing the grid file output in the step S2 into modal simulation software, defining a simulation frequency interval, simulating the frame mode of the frame model under each order frequency in the frequency interval by using the modal simulation software, and outputting a frame mode graph under each order frequency;
and S4, counting modal values of all positions on the frame in the frame modal graph corresponding to all the order frequencies, and taking the position with the maximum low modal coincidence degree in all the regions in the frame modal graph under different order frequencies as the position of a connecting point between the frame and the vehicle body in the region.
2. The method for determining the frame connection point of the non-load bearing electric vehicle according to claim 1, wherein: the frame structure three-dimensional model can be established through CATIA, UG or Pro/E, the finite element processing software is ANSA or HypermeSh, and the simulation software is NASTRAN or ABAQUS.
3. The method for determining the frame connection point of the non-self-supporting electric vehicle according to claim 1, wherein: the frequency interval is from 1HZ to the natural frequency of the motor carried by the frame.
4. The method for determining the frame connection point of the non-load bearing electric vehicle according to claim 1, wherein: the positions of the connection points of the vehicle bodies of the frames are symmetrically arranged relative to the width center line of the frames.
5. The method for determining the frame connection point of the non-load bearing electric vehicle according to claim 1, wherein: in step S4, the position of the frame body connection point is the position where the mode nodes in the area overlap most.
6. The method for determining the frame connection point of the non-load bearing electric vehicle according to claim 1, wherein: the finite element gridding processing in the step S2 comprises the following steps:
s21, removing redundant geometric figures including points, lines and round corners;
s22, performing a median plane drawing operation, and performing grid division on the median plane;
s23, creating a gridding division file and a quality inspection file to generate a grid, and inspecting the grid quality, correcting errors and poor-quality grids;
s24, separating the grid from the geometric model, deleting the originally imported frame structure model file, creating a welding unit and a rigid node, defining the material thickness and the material properties including the elastic modulus E, the NU Poisson' S ratio and the RHO density, and exporting the grid file.
7. The method for determining the frame connection point of the non-load bearing electric vehicle according to claim 1, wherein: the simulation in step S3 includes the following steps:
s31, creating a frame model generated by the grid file with the selected and imported attributes, and defining the thickness of the material;
s32, giving the material attribute and the material thickness to the frame model;
s33, creating a simulation environment, and defining a simulation frequency interval;
and S34, the ND calculates the order in the frequency interval, a control guidance calculation link solver is created to carry out corresponding calculation commands, and a simulated vehicle frame modal diagram is derived.
8. The method for determining a frame connection point of a non-self-supporting electric vehicle according to any one of claims 1 to 7, wherein: the area on the frame, which can be used as a connecting point between the frame and the vehicle body, at least meets the following conditions: easily the frame shaping does not influence the automobile body molding does benefit to the frame with assemble between the automobile body to and accord with the motorcycle type function definition.
9. The method for determining the frame connection point of the non-load bearing electric vehicle according to claim 8, wherein: the vehicle type function definition comprises that the vehicle is a passenger vehicle or a freight vehicle.
10. The utility model provides a non-formula electric automobile frame that bears which characterized in that: the front end and the rear end of the frame are provided with motors at least at the rear end, the middle part of the frame is fixedly provided with a battery pack, the frame is provided with a plurality of connecting pieces for connecting with a vehicle body, the connecting pieces are positioned at the connecting points between the frame and the vehicle body determined by the determination method of any one of claims 1 to 9, and the connecting pieces are elastic connecting pieces or rigid connecting pieces.
11. The non-load bearing electric vehicle frame of claim 10, wherein: the elastic connecting piece is suspended.
12. The utility model provides a non-formula electric automobile that bears which characterized in that: the non-self-supporting electric vehicle has the non-self-supporting electric vehicle frame of claim 10 or 11.
CN201811645878.5A 2018-12-30 2018-12-30 Method for determining connection point of non-bearing type electric automobile frame, non-bearing type electric automobile frame and electric automobile Active CN111400818B (en)

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Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102590340A (en) * 2012-02-29 2012-07-18 湖南湖大艾盛汽车技术开发有限公司 Detection equipment for welding spot failure of whole set of white vehicle body
CN102945307A (en) * 2012-11-27 2013-02-27 北京汽车股份有限公司 Automobile chassis key structural member structure optimization design method
CN104112050A (en) * 2014-07-23 2014-10-22 中国人民解放军装甲兵工程学院 Optimum design method of non-bearing frame structure of light vehicle
CN106294939A (en) * 2016-07-29 2017-01-04 重庆理工大学 Finite element occupant restraint system model based on Modularization modeling and modeling method thereof
CN108920740A (en) * 2018-04-28 2018-11-30 江铃控股有限公司 Suspend inner frame modal Optimization method and system
CN108959748A (en) * 2018-06-22 2018-12-07 上海思致汽车工程技术有限公司 A kind of stiffness analysis method of subframe and the attachment point of vehicle body flexible connection

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9348953B2 (en) * 2012-04-06 2016-05-24 Bridgestone Corporation Swing simulation system, swing simulation apparatus, and swing simulation method
CN104325733B (en) * 2014-09-26 2016-06-15 南车青岛四方机车车辆股份有限公司 Car body composite coating and method for designing thereof

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102590340A (en) * 2012-02-29 2012-07-18 湖南湖大艾盛汽车技术开发有限公司 Detection equipment for welding spot failure of whole set of white vehicle body
CN102945307A (en) * 2012-11-27 2013-02-27 北京汽车股份有限公司 Automobile chassis key structural member structure optimization design method
CN104112050A (en) * 2014-07-23 2014-10-22 中国人民解放军装甲兵工程学院 Optimum design method of non-bearing frame structure of light vehicle
CN106294939A (en) * 2016-07-29 2017-01-04 重庆理工大学 Finite element occupant restraint system model based on Modularization modeling and modeling method thereof
CN108920740A (en) * 2018-04-28 2018-11-30 江铃控股有限公司 Suspend inner frame modal Optimization method and system
CN108959748A (en) * 2018-06-22 2018-12-07 上海思致汽车工程技术有限公司 A kind of stiffness analysis method of subframe and the attachment point of vehicle body flexible connection

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
任杰锶,董小瑞.基于ANSYS Workbench的某越野车车架有限元分析.《中北大学学报(自然科学版)》.2015,第36卷(第4期),428-434、457. *
唐兆,等.基于试验与仿真相结合的动应力混合模拟.《内燃机车》.2012,(第2期),14-17. *

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