Patent Description:
With the increasingly stringent vehicle emission regulations in various countries and the rapid development of electric vehicle technologies, new energy vehicle models with power batteries as a sole or part of energy sources have already been paid more and more attention. Taking battery electric vehicles with the power batteries as the energy sources as an example, requirements on the mounting performance of powertrains are higher due to large start-up torques of the vehicles using electrically driven modes, which also results in higher strength performance target of front sub-frames of the vehicles; and meanwhile, as motors and battery packs of the whole vehicles are electrical elements, it is very important to know how to protect them reasonably during collisions.

<CIT> discloses shear plates for structurally connecting vehicle chassis front cradles to battery pack support trays, methods for making and methods for using such shear plates, and electric vehicles with a chassis frame having a front cradle coupled to a battery pack support tray by a shear plate.

<CIT> discloses a deformation device for a motor vehicle comprising at least one subframe element, at least one traction battery and at least one deformation element.

<CIT> discloses a floor undercover that can inhibit an increase in the drag coefficient in a case where the floor undercover is mounted to a bottom portion of a cabin located at a lower position than a front suspension member.

<CIT> discloses a kind of battery backplate which is arranged in the front of a vehicle-mounted battery pack of an electric car, wherein the battery backplate includes a first backplate and a second backplate being fixed to each other.

At present, most new energy vehicles are equipped with full-frame sub-frames, and in order to ensure the performance, their dimensions and weights are larger, which will affect the collision performance of sub-frames arising from the adverse deformation of sub-frames during collisions. In addition, the existing new energy vehicle models, in most cases, only have force-transfer passages on bodies, which may not meet requirements in MPDB, and other collision conditions; and as the new energy vehicle models, it is especially important for the protection on the battery packs and relevant connectors. However, the battery packs, in most cases, are protected by plastic guard boards, and sometimes, are even exposed without protection, in the existing new energy vehicles, resulting in large security risks during collisions or dragging bottom.

In view of the above, the present disclosure aims to provide a chassis collision structure of a new energy vehicle to improve a collision performance of a chassis of the new energy vehicle.

In order to achieve the above objectives, the technical solution of the present disclosure is achieved by providing a chassis collision structure according to the independent claim. Further embodiments are specified in the dependent claims.

The chassis collision structure of the new energy vehicle wherein the chassis collision structure of a new energy vehicle includes a front lower collision beam assembly, a front sub-frame assembly, a front battery pack bottom fender, a rear battery pack bottom fender, and a rear sub-frame assembly which are arranged sequentially along a direction from a head to a tail of the vehicle, wherein the front lower collision beam assembly is connected to a front end of the front sub-frame assembly; the front battery pack bottom fender is connected to a bottom of the front sub-frame assembly; the rear battery pack bottom fender is connected to a bottom of the rear sub-frame assembly; and connecting parts which are connected with a battery pack are arranged at one end of the front battery pack bottom fender and one end of the rear battery pack bottom fender, which are close to each other, respectively.

Further, the front lower collision beam assembly includes energy-absorbing boxes which are arranged on two sides, and a front lower collision beam which is connected with the energy-absorbing boxes on the two sides; and a length of the front lower collision beam, which is located between centers of the energy-absorbing boxes on the two sides, is larger than <NUM>% of an overall width of the vehicle.

Further, the front sub-frame assembly includes longitudinal beams of sub-frame, which are arranged on the two sides, a front cross member of sub-frame, which is connected between the longitudinal beams of sub-frame on the two sides and is close to a front end of each of the longitudinal beams of sub-frame, and a rear cross member of sub-frame, which is close to a rear end of each of the longitudinal beams of sub-frame with respect to the front cross beam of sub-frame; body connecting parts are arranged on each longitudinal beam of sub-frame; and the front sub-frame assembly further includes two powertrain front mounting installation parts which are arranged relatively on the two sides, and a powertrain rear mounting installation part which is arranged on the rear cross beam of sub-frame.

Further, body connecting parts on the longitudinal beams of sub-frame includes a front connecting part of body, a middle connecting part of body, and a rear connecting part of body which are arranged on each of the longitudinal beams of sub-frame along a length direction of each of the longitudinal beams of sub-frame; and the powertrain front mounting installation part on each side is arranged close to a junction of the front cross beam of sub-frame and the longitudinal beam of sub-frame on the side, and is provided with a front cross beam installation position arranged at the front cross beam of sub-frame, and a longitudinal beam installation position arranged at each of the longitudinal beams of sub-frame; and the powertrain rear mounting installation part is located in the middle of the rear cross beam of sub-frame in a length direction.

Further, a front installation position support is fixedly connected to a front end of each of the longitudinal beams of sub-frame; each front connecting part of body is a front installation drive pipe arranged on the front installation position support; the front installation drive pipe is located right above the corresponding longitudinal beams of sub-frame, and a tool pass-through part, which is over against the front installation drive pipe, for an external installation tool to pass through is arranged on the corresponding front longitudinal beam of sub-frame.

Further, a front mounting support which extends towards an inside of the longitudinal beam of sub-frame is fixedly connected to the longitudinal beam of sub-frame on one side; the longitudinal beam installation position at a position of the longitudinal beam of sub-frame on the side is arranged on the front mounting support; and the powertrain rear mounting installation part is provided with a plurality of rear cross beam installation positions which are distributed on the rear cross beam of sub-frame regularly.

Further, stabilization bar installation positions, large bushing installation positions of swing arms, and small bushing installation positions of swing arms which are opposite to each other are arranged on the longitudinal beams of sub-frame on the two sides; steering gear installation positions are arranged on the rear cross beam of sub-frame; and installation positions of front battery pack bottom fender are arranged on one side of the rear cross beam of sub-frame, which is back on to the front cross beam of sub-frame.

Further, the large bushing installation positions of swing arms are colinear with the stabilization bar installation positions along a length direction of each of the longitudinal beams of sub-frame, and the stabilization bar installation positions are located on a top of the longitudinal beams of sub-frame; the large bushing installation positions of swing arms are provided with first large bushing installation points and second large bushing installation points which are arranged at intervals along the length direction of the longitudinal beams of sub-frame; the first large bushing installation points are close to the stabilization bar installation positions and run through a bottom of the longitudinal beams of sub-frame; and the second large bushing installation points run through the longitudinal beams of sub-frame from top to bottom.

Further, a plurality of collapsing deformation intervals which are arranged along a length direction of the longitudinal beams of sub-frame are arranged on the longitudinal beams of sub-frame; each collapsing deformation interval is provided with a front interval located on a front end of each of the longitudinal beams of sub-frame, a middle interval close to a middle of each of the longitudinal beams of sub-frame, and a rear interval located on a rear end of each of the longitudinal beams of sub-frame, and a collapsing rib is arranged on the longitudinal beam of sub-frame at the middle interval; and a strip deformation guide port is formed in the longitudinal beam of sub-frame at the rear interval.

Further, a front cross beam inclined plane which inclines towards an outside of the cross beam of sub-frame is formed on an upper part of one side of the front cross beam of sub-frame, which is over against the rear cross beam of sub-frame; a curb stone entry part which extends outwards is arranged on one side of the rear cross beam of sub-frame, which is over against the front cross beam of sub-frame, and an up-dip upper inclined plane of the rear cross beam and a down-dip lower inclined plane of the rear cross beam are constructed at a top and a bottom of the rear cross beam of sub-frame and the curb stone entry part which are connected, respectively; a planar lifting contact part is arranged at a bottom of the rear cross beam of sub-frame; and a front battery pack fender connecting part which extends outwards is arranged on one side, which is back on to the front cross beam of sub-frame, of the rear cross beam of sub-frame.

Further, the front battery pack bottom fender is in a triangular shape; and a front sub-frame connecting part is arranged at a position of a vertex angle close to the front battery pack bottom fender; and the connecting parts which are connected with the battery pack are arranged along an edge of the front battery pack bottom fender, which is over against the front sub-frame connecting part.

Further, the rear battery pack bottom fender includes a bottom fender body which consists of a top fender and a bottom fender which are buckled fixedly from top to bottom; a plurality of rear battery pack connecting parts are arranged on one side of the bottom fender body, and a plurality of rear sub-frame connecting parts which are connected with the rear sub-frame assembly are constructed on the other side of the bottom fender body with respect to the rear battery pack connecting parts; and the rear battery pack connecting parts and the rear sub-frame connecting part are connecting holes which are formed in the bottom fender body.

Further, the top fender includes a straight middle connecting panel, and an upper left panel and an upper right panel which are fixedly connected to two ends of the middle connecting panel; the connecting holes are distributed in the upper left panel and the upper right panel, and one end of the upper left panel and one end of the upper right panel are in bifurcated forms; and a planar lifting contact part is formed on the bottom fender, with respect to the middle connecting panel.

Further, the bottom fender body is provided with a first edge which is linear and is located on one side of the rear battery pack connecting parts, and a second edge which is located on one side of the rear sub-frame connecting parts and extends to be connected with two ends of the first edge; the second edge is in an arc shape; the bottom fender at the second edge extends outwards with respect to the top fender; a flange is constructed on an overhang edge of the bottom fender; a plurality of drain holes are formed in the bottom fender; the flange (<NUM>) located in the middle of the second edge (<NUM>) is provided with an up-dip bulged part; and a bulged dimension of the bulged part is reduced gradually from the middle to the two sides.

Further, the rear sub-frame assembly includes a rear sub-frame main body, and two positioning supports which are arranged close to left ends and right of the rear sub-frame main body respectively; body connecting parts and rear battery pack bottom fender connecting parts are constructed on the rear sub-frame main body; stabilization bar installation parts, upper control arm installation parts, and lower control arm installation parts are arranged on the rear sub-frame main body; and positioning parts which are matched with an external positioning element to locate the rear sub-frame main body are constructed on the two positioning supports.

Further, the rear sub-frame main body has a bilaterally symmetrical structure, and includes a rear sub-frame body located in the middle, and rear sub-frame cross beams and stabilization bar installation supports which are arranged on two opposite sides of the rear sub-frame body respectively; the rear sub-frame main body further includes lower supports which are connected between the rear sub-frame cross beams on two sides and the rear sub-frame body respectively; and the positioning supports at two ends are fixedly connected to the stabilization bar installation support on the corresponding end.

Furthermore, the rear subframe body is provided with a rear subframe front plate and a rear subframe rear plate which are fixedly connected together in a lapped way, the rear subframe cross beams on the two sides are both fixedly connected with the rear subframe front plate in a lapped way, and the lower supports on the two sides are fixedly connected between the rear subframe front plate and the rear subframe cross beams on the corresponding sides.

Further, an internal reinforcement panel is fixedly connected between the rear sub-frame front panel and the rear sub-frame rear panel, and a rear installation position support panel is fixedly connected to the rear sub-frame rear panel; the plurality of body connecting parts and the plurality of rear battery pack bottom fender connecting parts are bilaterally symmetrical on the rear sub-frame main body; and the stabilization bar installation parts, the upper control arm installation parts, and the lower control arm installation parts are bilaterally symmetrical on the rear sub-frame main body, which have two groups.

Further, a bottom surface of the front sub-frame assembly and the front battery pack bottom fender which are connected shows a gradually-lowered stair-step shape along the direction from the head to the tail of the vehicle; and a bottom surface of the rear battery pack bottom fender shows a down-dip shape form along the direction from the head to the tail of the vehicle.

Compared with the prior art, the present disclosure has the following advantages:
According to the chassis collision structure of the new energy vehicle of the present disclosure, the front lower collision beam assembly, the front sub-frame assembly, the front battery pack bottom fender, the rear battery pack bottom fender, and the rear sub-frame assembly are arranged sequentially along the length direction of the vehicle, the front lower collision beam assembly, the front sub-frame assembly, and the front battery pack bottom fender are connected together, the rear battery pack bottom fender is connected with the rear sub-frame assembly together, and the connecting parts which are connected with the battery pack are arranged on the front battery pack bottom fender and the rear battery pack bottom fender respectively; and an collision system which is located at the vehicle chassis may be formed based on the above structures in combination with the battery pack connected therewith, and thus, the deformation of the chassis structure may be guided to caused or increased in specific areas through the structural design of each part, thereby improving the collision performance of the chassis of the new energy vehicle.

The above description is only the overview of the technical solutions of the present disclosure, implementation may be performed according to the content of the specification in order to more clearly understand the technical means of the present disclosure, and specific embodiments of the present disclosure are listed below in order to make the above and other objectives, features and advantages of the present disclosure more obvious and understandable.

Accompanying drawings constituting a part of the present disclosure are used for further understanding the present disclosure, and schematic embodiments of the present disclosure and their description are used for explaining the present disclosure instead of improperly limiting it. In the drawings:.

Brief description of references of the drawings:.

To make the objectives, technical solutions, and advantages of the embodiments of the present disclosure clearer, the following clearly and completely describes the technical solutions in the embodiments of the present disclosure with reference to the accompany drawings in the embodiments of the present disclosure. Obviously, the descried embodiments are part, not all of the embodiments of the present disclosure. Based on the embodiments in the present disclosure, all other embodiments obtained by those ordinarily skilled in the art without involving creative labor belong to the protection scope of the present disclosure.

The present disclosure may be illustrated in details below with reference to the drawings and the embodiments.

The embodiment relates to a chassis collision structure of a new energy vehicle, as shown in the <FIG>, which includes a front lower collision beam assembly <NUM>, a front sub-frame assembly <NUM>, a front battery pack bottom fender <NUM>, a rear battery pack bottom fender <NUM>, and a rear sub-frame assembly <NUM> which are arranged sequentially along a direction from a head to a tail of a vehicle.

The front lower collision beam assembly <NUM> is connected to a front end of the front sub-frame assembly <NUM>; the front battery pack bottom fender <NUM> is connected to a bottom of the front sub-frame assembly <NUM>; the rear battery pack bottom fender <NUM> is connected to a bottom of the rear sub-frame assembly <NUM>; connecting parts which are connected with a battery pack <NUM> are arranged at one end of the front battery pack bottom fender <NUM> and one end of the rear battery pack bottom fender <NUM>, which are close to each other, respectively; and the connecting parts are front battery pack connecting parts <NUM> and rear battery pack connecting parts <NUM>, respectively.

As a preferred embodiment, connections between the front lower collision beam assembly <NUM> and the front sub-frame assembly <NUM>, between the front sub-frame assembly <NUM> and the front battery pack bottom fender <NUM>, between the rear battery pack bottom fender <NUM> and the rear sub-frame assembly <NUM>, between the front battery pack bottom fender <NUM> and a battery pack <NUM>, and between the rear battery pack bottom fender <NUM> and the battery pack <NUM> may be achieved by a bolt structure.

With reference to <FIG>, the front lower collision beam assembly <NUM> specifically includes energy-absorbing boxes <NUM> which are arranged on two sides, and a front lower collision beam <NUM> which is connected with the energy-absorbing boxes <NUM> on the two sides. The energy-absorbing boxes <NUM> on the two sides are connected with the front sub-frame assembly <NUM> by a sub-frame connecting panel <NUM> located at one end of each energy-absorbing box, and are particularly connected with energy-absorbing box connecting panels <NUM> by the bolt structure. The front lower collision beam <NUM> is connected with the energy-absorbing boxes <NUM> on the two sides in a welded mode; and in addition to the welding mode, the front lower collision beam may also be connected with the energy-absorbing boxes by bolted connection, and other means.

In the embodiment, as shown in the <FIG>, a plurality of collapsing parts k1, k2, and k3 are arranged at intervals on each energy-absorbing box <NUM> along a length direction of each energy-absorbing box; and each collapsing part may, for example, consist of bulges formed at an upper end face and a lower end face of each energy-absorbing box <NUM>, and pits formed at a left end face and a right end face of each energy-absorbing box <NUM> corresponding to the position of the bulges. Of course, in addition to a mode of bulging at the upper end and the lower end and recessing on both sides, collapsing holes, and other existing collapsing forms may also be used for the collapsing parts on the energy-absorbing boxes <NUM>.

In the embodiment, in order to improve the collision performance of the front lower collision beam assembly <NUM>, and particularly, meet the performance of <NUM>% frontal collision of the vehicle, a length L of the front lower collision beam <NUM>, which is located between centers of the energy-absorbing boxes <NUM> on the two sides, is larger than <NUM>% of an overall width of the vehicle. As an preferred exemplary form, as shown in <FIG>, the front lower collision beam <NUM> includes a linear segment located in the middle, and arc segments which are located at two ends of the linear segment; the arc segments at two ends bend towards one side of each energy-absorbing box <NUM>, that is, one side of the tail of the vehicle, with a bending radian matched with a bumper on the head of the vehicle; and meanwhile, widths outside bending parts of the front lower collision beam <NUM> should also fall within the range of action of a "pendulum test" during design.

In order to ensure the structural strength of the front lower collision beam <NUM>, in the embodiments, preferably, a section of the front lower collision beam <NUM> is designed as a square shape or a rectangle shape, for example, the front lower collision beam <NUM> may be formed by directly bending square steel. In addition, in order to the improve the stiffness of the front lower collision beam <NUM> during the frontal collision of the vehicle, in the embodiments, a reinforcement panel <NUM> which is fixedly connected to one side of the front lower collision beam <NUM> may also be arranged in the middle of the front lower collision beam <NUM> in the length direction. The reinforcement panel <NUM> has an extension length along the length direction of the front lower collision beam <NUM>, which may, for example, be arranged on an inner side, which faces towards the front sub-frame assembly <NUM>, of the front lower collision beam <NUM>.

As shown in the <FIG> and <FIG>, in the embodiments, the front sub-frame assembly <NUM> includes two longitudinal beams <NUM> of sub-frame, which are arranged on two sides, a front cross beam <NUM> of sub-frame, which is connected between the longitudinal beams <NUM> of sub-frame and is close to a front end of the longitudinal beams <NUM> of sub-frame, and a rear cross beam <NUM> of sub-frame, which is close to a rear end of the longitudinal beams <NUM> of sub-frame with respect to the front cross beam <NUM> of sub-frame; and front connecting parts <NUM> of body, middle connecting parts <NUM> of body, and rear connecting parts <NUM> of body which are opposite to each other are arranged on the longitudinal beams <NUM> of sub-frame on the two sides along the length direction of the longitudinal beams <NUM> of sub-frame.

Meanwhile, the front sub-frame assembly <NUM> further includes two powertrain front mounting installation parts <NUM> which are arranged on the two sides oppositely, and a powertrain rear mounting installation part <NUM> which is arranged on the rear cross beam <NUM> of sub-frame. Wherein the powertrain front mounting installation part <NUM> on each side is arranged close to a junction of the front cross beam <NUM> of sub-frame and the longitudinal beam <NUM> of sub-frame on the side, and is provided with a front cross beam installation position <NUM> arranged at the front cross beam <NUM> of sub-frame, and a longitudinal beam installation position <NUM> arranged at the longitudinal beams <NUM> of sub-frame. The powertrain rear mounting installation part <NUM> is located in the middle of the rear cross beam <NUM> of sub-frame in the length direction.

In the embodiment, in terms of a motor in a cabin of the new energy vehicle, which is arranged on a left side, during design, a front mounting support <NUM> which extends towards an inner side of the longitudinal beam <NUM> of sub-frame is fixedly connected to the longitudinal beam <NUM> of sub-frame on one side, that is, a right side, shown in <FIG>, in order to improve the utilization rate of longitudinal beam materials, and the longitudinal beam installation position <NUM> of the longitudinal beam <NUM> of sub-frame on the side is arranged on the front mounting support <NUM>. In addition, with reference to <FIG>, in the embodiments, the front cross beam installation positions <NUM> and the longitudinal beam installation positions <NUM> may be arranged fixedly by threaded pipes. Of course, in addition to the threaded pipes, other installation structures, such as connecting holes, are also available.

In the embodiment, the powertrain rear mounting installation part <NUM> on the rear cross beam <NUM> of sub-frame is provided with a plurality of rear cross beam installation positions z which are distributed on the rear cross beam <NUM> of sub-frame regularly, wherein the four rear cross beam installation positions z are distributed in a square shape, as shown in the <FIG>; and during design, the connecting holes which run through the rear cross beam <NUM> of sub-frame may be used as the rear cross beam installation positions z. Meanwhile, in order to ensure the structural strength of rear cross beam installation positions z, a support pipe may be arranged in the rear cross beam <NUM> of sub-frame with respect to each connecting hole, which is fixedly welded in the rear cross beam <NUM> of sub-frame.

As shown in the <FIG>, from the assembled state of powertrain front mountings <NUM> and powertrain rear mountings <NUM> on the front sub-frame assembly <NUM>, it can be seen that two powertrain front mountings <NUM> are assembled on the front sub-frame assembly <NUM> along a height direction of the front sub-frame assembly <NUM>, that is, a Z direction of the vehicle, by the front cross beam installation positions <NUM> and the longitudinal beam installation positions <NUM> in the two powertrain front mounting installation parts <NUM>. Therefore, it is conducive to reduction in the occupation of cabin space along the overall length direction of the vehicle, thereby facilitating the assembly of components.

In the embodiment, energy-absorbing box connecting panels <NUM> are fixedly connected to front ends of the longitudinal beams <NUM> of sub-frame on the two sides respectively, by which the energy-absorbing boxes <NUM> in the front lower collision beam assembly <NUM> are in bolted connection with the longitudinal beams <NUM> of sub-frame. In the embodiments, a front installation position support <NUM> is fixedly connected to the front end of the longitudinal beams <NUM> of sub-frame, and a middle installation position support <NUM> is also fixedly connected to the middle of the longitudinal beams <NUM> of sub-frame.

At this moment, the front connecting parts <NUM> of body are arranged on the front installation position supports <NUM>, the middle connecting parts <NUM> of body are arranged on the middle installation position supports <NUM>, and the rear connecting parts <NUM> of body are directly arranged at rear ends of the longitudinal beams <NUM> of sub-frame.

With reference to <FIG>, each front installation position support <NUM> may consist of inner and outer panels which are buckled fixedly, and each front connecting part <NUM> of body, which is located thereon, may have a support pipe structure which is fixedly connected to the top of each front installation position support <NUM>. Meanwhile, it should be noted that preferably, the front installation position supports <NUM> and the powertrain front mounting installation part <NUM> on the same side keep as close as possible during arrangement on the basis of ensuring the structural performance of the powertrain front mounting installation parts <NUM> and the front connecting parts <NUM> of body, so that the dynamic stiffness of the front mountings is strengthened by increasing local dimensions to a maximum extent in case that the space is available.

Preferably, in terms of construction, each middle installation position support <NUM> may also consist of the inner and the outer panels which are buckled fixedly, which is the same as the front installation position supports <NUM>, and the middle connecting parts <NUM> of body, which are located thereon, may also have support pipe structures which are fixedly welded on tops of the middle installation position supports <NUM>. The rear connecting parts <NUM> of body, which are directly arranged on ends of the longitudinal beams <NUM> of sub-frame, also have the support pipe structures which are fixedly welded in the longitudinal beams <NUM> of sub-frame.

In the embodiment, stabilization bar installation positions <NUM>, large bushing installation positions <NUM> of swing arms, and small bushing installation positions <NUM> of swing arms which are opposite to each other are arranged on the longitudinal beams <NUM> of sub-frame on the two sides. Meanwhile, steering gear installation positions <NUM> are also arranged on the rear cross beam <NUM> of sub-frame, installation positions <NUM> of front battery pack bottom fender, at which the battery pack fenders are connected, are arranged on one side of the rear cross beam <NUM> of sub-frame, which is back on to the front cross beam <NUM> of sub-frame.

Wherein, the stabilization bar installation positions <NUM>, the large bushing installation positions <NUM> of swing arms, and the small bushing installation positions <NUM> of swing arms may be installation holes which are formed in the longitudinal beams <NUM> of sub-frame; and installation supports may be arranged additionally inside the longitudinal beams <NUM> of sub-frame with respect to swing arm bushing installation points to ensure the stability of swing arm bushings in installation.

In addition, in the embodiment the large bushing installation positions <NUM> of swing arms are colinear with the stabilization bar installation positions <NUM> along the length direction of the longitudinal beams <NUM> of sub-frame, and the stabilization bar installation positions <NUM> are located on a top of the longitudinal beams <NUM> of sub-frame; and the large bushing installation positions <NUM> of swing arms are provided with first large bushing installation points <NUM> and second large bushing installation points <NUM> which are arranged at intervals along the length direction of the longitudinal beams <NUM> of the sub-frame. With reference to <FIG>, the first large bushing installation points <NUM> are close to the stabilization bar installation positions <NUM> and only run through bottoms of the longitudinal beams <NUM> of sub-frame, that is, longitudinal beam lower panels <NUM> of the longitudinal beams <NUM> of sub-frame; and the second large bushing installation positions <NUM> run through the longitudinal beams <NUM> of sub-frame from top to bottom, that is, they run through longitudinal beam upper panels <NUM> and the longitudinal beam lower panels <NUM>.

The stabilization bar installation positions <NUM> and the large bushing installation positions <NUM> of swing arms are arranged at relative positions, which may facilitate the assembly of stabilization bars and large bushings of swing arms on the sub-frame assembly. In addition, for the purpose of improving the collision energy absorption performance of the longitudinal beams <NUM> of sub-frame in the sub-frame assembly, as shown in the <FIG> of the embodiments, a plurality of collapsing deformation intervals arranged along the length direction of the longitudinal beams <NUM> of sub-frame are arranged on the longitudinal beams <NUM> of sub-frame respectively.

Wherein, in the specific design, the collapsing deformation intervals have front intervals b located on front ends of the longitudinal beams <NUM> of sub-frame, middle intervals c close to the middle of the longitudinal beams <NUM> of sub-frame, and rear intervals d located on rear ends of the longitudinal beams <NUM> of sub-frame. The length of each interval may be selected based on the overall structural design of the longitudinal beams, the stiffness of the position of the powertrain front mounting installation parts <NUM>, and the collision performance design of the vehicle, and generally, collapsing ribs <NUM> are arranged on the longitudinal beams <NUM> of sub-frame at the middle intervals c, and strip deformation guide ports <NUM> are formed in the longitudinal beams <NUM> of sub-frame at the rear intervals d to ensure the collapsing energy absorption effect of the longitudinal beams <NUM> of sub-frame.

As mentioned above, the longitudinal beams <NUM> of sub-frame consist of the longitudinal beam upper panels <NUM> and the longitudinal beam lower panels <NUM> which are buckled fixedly. In the embodiments, the front cross beam <NUM> of sub-frame and the rear cross beam <NUM> of sub-frame consist of two sheet metals which are buckled, respectively, which are the same as most of the cross beams and the longitudinal beams in the existing vehicle. With reference to <FIG>, the front cross beam <NUM> of sub-frame consists of an upper panel <NUM> of front cross beam and a lower panel <NUM> of front cross beam; and the rear cross beam <NUM> of sub-frame consists of an upper panel <NUM> of rear cross beam and a lower panel <NUM> of rear cross beam.

Combined with the constitute of the above cross beam structure, in the embodiment, in order to reduce an influence on the collapsing deformation of the longitudinal beams <NUM> of sub-frame by sliding a powertrain upwards during the collision, an inclined plane <NUM> of front cross beam, which inclines towards an outside of the front cross beam <NUM> of sub-frame, is formed on an upper part of one side of the front cross beam <NUM> of sub-frame, which is over against the rear cross beam <NUM> of sub-frame, and an upper inclined plane <NUM> of rear cross beam, which inclines towards an outside of the rear cross beam <NUM> of sub-frame, is also arranged on an upper part of one side of the rear cross beam <NUM> of sub-frame, which is over against the front cross beam <NUM> of sub-frame. The inclined plane <NUM> of front cross beam and the upper inclined plane <NUM> of rear cross beam constitute a guide surface, where the powertrain may slide upwards.

Further, in the embodiment, a curb stone entry part <NUM> which extends outwards is also arranged on one side of the rear cross beam <NUM> of sub-frame, which is over against the front cross beam <NUM> of sub-frame; the upper inclined plane <NUM> of rear cross beam is located at a top of the rear cross beam <NUM> of sub-frame, which is connected with the curb stone entry part <NUM>, and a lower inclined plane <NUM> of rear cross beam, which inclines backwards, is a bottom of the rear cross beam <NUM> of sub-frame, which is connected with the curb stone entry part <NUM>. In addition, a planar lifting contact part <NUM> is arranged at the bottom of the rear cross beam <NUM> of sub-frame, and a front battery pack fender connecting part <NUM> which extends outwards is also arranged on one side of the rear cross beam <NUM> of sub-frame, which is back on to the front cross beam <NUM> of sub-frame.

The front battery pack fender connecting part <NUM> and the curb stone entry part <NUM> are in plate shapes, both of which are specifically formed by extending the lower panel <NUM> of rear cross beam outwards on the corresponding side; the front battery pack bottom fender installation positions <NUM> are arranged on the front battery pack fender connecting part <NUM>; and generally, the front battery pack bottom fender installation positions <NUM> are installation holes formed in the front battery pack fender connecting part <NUM>. In addition, an included angle between the lower inclined plane <NUM> of rear cross beam and a horizontal plane is, generally, designed as <NUM>° to <NUM>°, and an included angle between the inclined plane <NUM> of front cross beam and the horizontal plane and an included angle between the upper inclined plane <NUM> of rear cross beam and the horizontal plane are selected based on specific cases.

In the embodiment, the vehicle may pass through a curb stone by means of a ground clearance of the curb stone entry part <NUM> by the design of the curb stone entry part <NUM>, and may drive across the curb stone under special conditions in combination with the arrangement of the lower inclined plane <NUM> of rear cross beam at a rear of the curb stone entry part, thereby reducing damages arising from bumping against the curb stone, and other structures. The lifting contact part <NUM> is specifically a plane which is formed on the bottom of the rear cross beam <NUM> of sub-frame, where the sub-frame assembly may be lifted during maintenance; and an area of the lifting contact part <NUM> may depend on an overall structure of the rear cross beam <NUM> of sub-frame and a fit between components to perform specific selection.

In the embodiments, the sub-frame assembly <NUM> may be combined with the installed powertrain to improve the overall structural stability by the three-point arrangement of the powertrain front mounting installation parts and the powertrain rear mounting installation part; and the mounting stiffness is improved by the higher stiffness of the front cross beam <NUM> of sub-frame and the longitudinal beams <NUM> of sub-frame based on the arrangement that the powertrain front mounting installation parts <NUM> are close to the junction of the front cross beam <NUM> of sub-frame and the longitudinal beams <NUM> of sub-frame, and are provided with installation positions which are located on the front cross beam and the longitudinal beams respectively, thereby ensuring the mounting stiffness on the front sub-frame.

Meanwhile, the front sub-frame assembly <NUM> may meet requirements of different safety collision conditions, such as 56FF, MODB, ODB, FP, and RCAR etc., in combination with designs of the collapsing deformation intervals on the longitudinal beams <NUM> of sub-frame, the inclined plane <NUM> of front cross beam, and the upper inclined plane <NUM> of rear cross beam.

In addition, particularly, in the embodiment, for the front connecting parts <NUM> of body, for ease of operation during the connection of the front sub-frame and the body, also as shown in <FIG>, the front installation drive pipes <NUM> arranged on the front installation position supports <NUM> are used as the front connecting parts <NUM> of body, which have installation drive pipe structures; and the front installation drive pipes <NUM> are located right above of the corresponding front longitudinal beams <NUM> of sub-frame, which are over against the front installation drive pipes <NUM>; and tool pass-through parts for external installation tools to pass through are arranged on the corresponding front longitudinal beams <NUM> of sub-frame.

The external installation tools through which the tool pass-through parts pass are tools for connecting the front connecting parts <NUM> of body with the body; and as the connection is completed with a bolt structure, the external installation tools, for example, may be sleeve tools with extension rods. Meanwhile, the tool pass-through parts located on the longitudinal beams <NUM> of sub-frame may, generally, be via-through drive pipes <NUM> which are arranged on the longitudinal beams <NUM> of sub-frame; and the via-through drive pipes <NUM> run through two ends of upper end and lower end of the longitudinal beams <NUM> of sub-frame, and are fixed on the longitudinal beams <NUM> of sub-frame by welding.

In the embodiments, the front battery pack bottom fender <NUM> may protect a front end of the battery pack <NUM>; at this moment, with reference to <FIG>, the front battery pack bottom fender <NUM>, as an exemplary structural form, in the embodiment shows a triangular shape; a front sub-frame connecting part which is connected with the front sub-frame assembly <NUM> is arranged close to a vertex angle of the front battery pack bottom fender <NUM>; and the front battery pack connecting parts <NUM> which are connected with the battery pack <NUM> are arranged on an edge of the front battery pack bottom fender <NUM>, which is over against the front sub-frame connecting part.

Wherein, the front sub-frame connecting part arranged close to a front end of the front battery pack bottom fender <NUM> has, generally, a connecting hole structure which is formed on the front battery pack bottom fender <NUM>, and may be matched with the front battery pack bottom fender installation positions <NUM> for connections by the bolt structure. The front battery pack connecting parts <NUM> which are distributed along a rear end edge of the front battery pack bottom fender <NUM> have also the connecting hole structures, which are similar with the front sub-frame connecting part; and generally, the connection of a shell of the battery pack <NUM> with the front battery pack connecting parts <NUM> is achieved by the bolt structure.

In addition, as a preferred embodiment, as shown in <FIG>, a bottom surface of the front sub-frame assembly <NUM> and the front battery pack bottom fender <NUM> which are connected, shows a gradually-lowered stair-step shape from the head to the tail of the vehicle, and the lowest position is at least flush with, and even, slightly lower than the bottom of the battery pack <NUM>, so that the vehicle may overcome bellying conditions of curb stones or big stones to put over smoothly, thereby avoiding the frontal collision during traveling.

In the embodiments, the rear sub-frame assembly <NUM> is in fit with the rear battery pack bottom fender <NUM>, which is shown in <FIG>; the rear battery pack bottom fender <NUM> is not only connected to a bottom of the rear sub-frame assembly <NUM>, but is also connected to the bottom of the rear end of the battery pack <NUM>; and the rear sub-frame assembly <NUM> is in bolted connection with a lower floor assembly <NUM> in the body by a drive pipe structure arranged on the rear sub-frame assembly.

In the embodiment, the rear sub-frame assembly <NUM> is shown in <FIG>, which includes a rear sub-frame main body and positioning supports in a structure. As a preferred exemplary form, the rear sub-frame main body has a bilaterally symmetrical structure, on which body connecting parts, rear battery pack bottom fender connecting parts, stabilization bar installation parts, and upper control arm installation parts, and lower control arm installation parts are constructed. Meanwhile, in the embodiment, each body connecting part is arranged on an upper part of the rear sub-frame main body and is connected with the rear sub-frame main body; and each rear battery pack bottom fender connecting part is constructed on a lower part of the rear sub-frame main body and is connected with the rear sub-frame main body.

The two positioning supports are arranged close to two ends of the left end and the right end of the rear sub-frame main body, and positioning parts are constructed on the two positioning supports respectively and may be matched with external positioning parts for positioning the rear sub-frame main body.

In the embodiments, the rear sub-frame assembly <NUM> has a symmetrical structure, which is easy to form, and compact in the structure, and thus, the dimension and the weight of the rear sub-frame assembly <NUM> may be reduced. Based on this, in detail, the rear sub-frame main body specifically includes a rear sub-frame body, rear sub-frame cross beams <NUM>, stabilization bar installation supports <NUM>, and lower supports <NUM>; the rear sub-frame body is located in the middle of the rear sub-frame main body; the rear sub-frame cross beams <NUM> and the stabilization bar installation supports <NUM> are arranged on two opposite sides of the rear sub-frame body respectively; and the positioning supports are fixedly connected to the stabilization bar installation supports <NUM> on the corresponding ends respectively. The lower supports <NUM> are arranged and connected between the rear sub-frame cross beams <NUM> on two sides and the rear sub-frame body respectively.

Still combined with <FIG> and <FIG>, in the embodiments, the rear sub-frame body is provided with a rear sub-frame front panel <NUM> and a rear sub-frame rear panel <NUM> which are overlapped fixedly, wherein the rear sub-frame front panel <NUM> is approximately in an "L" shape, and includes a vertical panel extending along the height direction of the vehicle, and a transverse panel extending to the tail along the length direction of the vehicle. In addition, two convex parts which are convex outwards and mutually symmetric are also formed on the cross plate, and first through holes allowing vehicle body rear mounting position supporting pipes <NUM> to penetrate are formed in the convex parts.

In the embodiment, the rear sub-frame rear panel <NUM> has a plate structure which bends towards the head approximately, and a top is in overlap joint with the transverse panel of the rear sub-frame front panel <NUM>. Preferably, an amount of overlap between the rear sub-frame rear panel <NUM> and the rear sub-frame front panel <NUM> is set as <NUM> that they have good anti-rust performance, while achieving reduction in the overall weight. Of course, the specific number value of the amount of overlap may be correspondingly adjusted according to specific conditions besides <NUM>.

It should be noted that in order to improve the using effect, as shown in the <FIG>, inner reinforcement panels <NUM> are fixedly connected to a bottom of the rear sub-frame front panel <NUM> and a bottom of the rear sub-frame rear panel <NUM>. With respect to the bulged parts, rear installation position support panels <NUM> are fixedly connected to the bottom of the rear sub-frame rear panel <NUM>, and second through holes <NUM> which are aligned with the first through holes are formed in the rear installation position support panels <NUM>.

In the embodiments, the rear sub-frame cross beams <NUM> on the two sides are in fixed overlap joint with the rear sub-frame front panel <NUM>; and the lower supports <NUM> on the two sides are fixedly connected between the rear sub-frame front panel <NUM> and the bottom of the rear sub-frame cross beam on the corresponding side. Preferably, the amount of overlap between the rear sub-frame cross beams <NUM> and the rear sub-frame is <NUM> to improve the anti-rust performance. Of course, the specific number value of the amount of overlap may be correspondingly adjusted according to specific conditions besides <NUM>.

In the embodiments, the rear sub-frame cross beams <NUM> are approximately in "L" shapes, and includes cross beam main bodies arranged along the width direction of the vehicle and bending parts which bend and extend towards the head direction of the vehicle. In addition, flanges which fold over towards one side of the rear sub-frame front panel <NUM> are formed on the two ends of the upper end and the lower end of the rear sub-frame cross beams <NUM>; and the rear sub-frame cross beams <NUM> are in fixed overlap joint with the rear sub-frame front panel <NUM> by the flanges, and the amount of overlap between the rear sub-frame cross beams <NUM> and the rear sub-frame front panel <NUM> is also <NUM> preferably. In addition, the first installation grooves at which the front installation position support pipes <NUM> of body are arranged are formed at the ends of the flanges at the lower ends of the rear sub-frame cross beams.

In the embodiments, each of stabilization bar installation supports <NUM> shows an "L" shape integrally, and is fixedly connected with the cross beam main bodies and the bending parts of the rear sub-frame cross beams <NUM> respectively, thereby improving the stability of the stabilization bar installation supports <NUM> in arrangement. In addition, two run-through holes <NUM> which are distributed at intervals are formed in the stabilization bar installation supports <NUM>, through which bolts, and other external connecting parts may pass. In addition, second installation grooves at which the front installation position support pipes <NUM> of body are arranged are formed at the ends of the stabilization bar installation supports <NUM>.

It should be noted that in order to improve the present disclosure effect of the rear sub-frame assembly, both a plurality of body connecting parts and a plurality of rear battery pack bottom fender connecting parts on the rear sub-frame assembly <NUM> are bilaterally symmetrical on the rear sub-frame main body, and that as a preferred embodiment, the quantity of body connecting parts and the rear battery pack bottom fender connecting parts are both four. In the embodiments, based on structures and operational performance of the existing stabilization bars and control arms, the stabilization bar installation parts, the upper control arm installation parts, and the lower control arm installation parts are two groups, which are bilaterally symmetrical on the rear sub-frame main body.

Wherein, the body connecting parts on the rear sub-frame assembly <NUM> includes the front installation position support pipes <NUM> of body and rear installation position support pipes <NUM> of body specifically; and the front installation position support pipes <NUM> of body are embedded into the first installation grooves and the second installation grooves, and are fixedly connected with the rear sub-frame cross beams <NUM> and the stabilization bar installation supports <NUM> respectively. The vehicle body rear mounting position supporting pipes <NUM> transversely penetrate through the rear subframe front plate <NUM>, specifically penetrate into the above first through holes and the above second through holes <NUM>, and are also fixedly connected with the rear subframe front plate <NUM> and rear mounting position supporting pipes. It should be noted that in addition to the front installation position support pipes <NUM> of body and the rear installation position support pipes <NUM> of body, the body connecting parts on the rear sub-frame assembly <NUM> further include other structures by which the rear sub-frame assembly <NUM> is connected with the body.

As shown in <FIG> and <FIG>, the rear battery pack bottom fender connecting parts of the embodiment include extra-fender installation position threaded pipes <NUM> and intra-fender installation position welded nuts <NUM>. Wherein the guard plate outer mounting position threaded pipes <NUM> are arranged on the lower supports <NUM> and the rear subframe cross beams <NUM> in a penetrating manner and fixedly connected with the lower supports and the rear subframe cross beams, thus, the guard plate outer mounting position threaded pipes, the lower supports and the rear subframe cross beams may be connected to be one body, so as to effectively improve the overall rigidity of the rear subframe main body. The intra-fender installation position welded nuts <NUM> are fixedly arranged on one side of each of the inner reinforcement panels <NUM>, which faces towards the rear sub-frame front panel <NUM>, and via holes are formed in the inner reinforcement panels <NUM> with respect to the intra-fender installation position welded nuts <NUM>, so that the bolts, and other external connecting pieces pass through the via holes and are in threaded connection with the intra-fender installation position welded nuts <NUM>.

It should be noted that in addition to the extra-fender installation position threaded pipes <NUM> and the intra-fender installation position threaded pipes, the rear battery pack bottom fender connecting parts further includes other structures by which the rear sub-frame assembly <NUM> is connected with the rear battery pack bottom fender <NUM>.

In the embodiment, the stabilization bar installation parts on the rear sub-frame assembly <NUM> specifically include stabilization bar installation position welded nuts <NUM> and stabilization bar installation position threaded pipes <NUM>; and the stabilization bar installation position welded nuts <NUM> are arranged corresponding to the run-through hole <NUM> close to ends of the stabilization bar installation supports <NUM>, and are fixedly connected to lower surfaces of the stabilization bar supports. The stabilization bar installation position threaded pipes <NUM> are arranged corresponding to the other run-through hole <NUM>, are arranged across the flanges on the lower ends of the rear sub-frame cross beams <NUM>, and are fixedly connected with the flanges and the stabilization bar installation supports <NUM>.

With reference to <FIG> and <FIG> based on <FIG>, the upper control arm installation parts on the rear sub-frame assembly <NUM> consist of the upper control arm installation positions <NUM> of front panel and the upper control arm installation positions <NUM> of rear panel which are arranged on the rear sub-frame front panel <NUM> and the front sub-frame rear panel <NUM>; and the two upper control arm installation positions are located on the same height of the rear sub-frame main body, which are through holes. Similarly, the lower control arm installation parts on the rear sub-frame assembly <NUM> of the embodiments consist of lower control arm installation positions <NUM> of front panel and lower control arm installation positions <NUM> of rear panel which are correspondingly arranged on the rear sub-frame front panel <NUM> and the front sub-frame rear panel <NUM>; and the two lower control arm installation positions are located on the same height of the rear sub-frame main body, which are through holes.

It should be illustrated that in addition to the through holes, other installation structures which are used commonly by a person skilled in the art may also be used as each control arm installation position on the rear sub-frame assembly <NUM>.

In addition, the two positioning supports in the rear sub-frame assembly <NUM> specifically include a main positioning support <NUM> on a left side and an auxiliary positioning support <NUM> on a right side, wherein both of which have the same in overall structures, and are fixedly connected to lower parts of the rear sub-frame cross beams <NUM> on the corresponding side; and positioning parts formed in the two positioning supports are positioning holes, and positioning pins may be used as the positioning parts. It should be illustrated that in order to facilitate the installation of the rear sub-frame assembly <NUM> of the embodiment, the positioning hole in the main positioning support <NUM> is a circular hole, and the positioning hole in the auxiliary positioning support <NUM> is a strip hole.

In the embodiment, the rear sub-frame assembly <NUM> is connected with the body by four installation positions on an upper end, and is connected with the rear battery pack bottom fender <NUM> by four installation positions on a lower end, so that the overall stiffness of the rear sub-frame assembly <NUM> may be improved effectively, thereby achieving better lateral stiffness and operation stability of a chassis structure with the rear sub-frame assembly <NUM>; and meanwhile, the arrangement of a plurality of fixed structures in the rear sub-frame assembly <NUM> may also facilitate the installation of rear axle stabilization bars and control arms.

In the embodiment, a structure of the rear battery pack bottom fender <NUM> is shown in <FIG>, the rear battery pack bottom fender <NUM> may protect the rear end of the battery pack <NUM>, and includes a bottom fender body which consists of a top fender <NUM> and a bottom fender <NUM> which are buckled fixedly from top to bottom; a plurality of rear battery pack connecting parts <NUM> which are connected with the battery pack <NUM> are constructed on one side of the bottom fender body, and meanwhile, a plurality of rear sub-frame connecting parts which are connected with the rear sub-frame assembly <NUM> are constructed on the other side of the bottom fender body with respect to the rear battery pack connecting parts <NUM>.

As a preferred embodiment, each rear battery pack connecting part <NUM> and each rear sub-frame connecting part are connecting holes formed in the bottom fender body, at this moment, each connecting hole runs through the top fender <NUM> and the bottom fender <NUM>; and for convenience for description, each connecting hole in the rear battery pack connecting parts <NUM> is a battery pack connecting hole <NUM>, while each connecting hole in the rear sub-frame connecting parts is called a rear sub-frame connecting hole <NUM>. Particularly, the bottom fender body is connected with the battery pack <NUM> and the rear sub-frame assembly <NUM> by a bolt pair structure which runs through the connecting holes.

In order to improve the structural strength of positions where the connecting holes are formed, bulges are constructed on the top fender <NUM> and the bottom fender <NUM> with respect to each connecting hole, which are in one-to-one correspondence; and each connecting hole runs through each bulge corresponding to the connecting hole. At this moment, in combined with <FIG>, each bulge on the top fender <NUM> is a top fender bulge <NUM>, and each bulge on the bottom fender <NUM> is a bottom fender bulge <NUM>. Each top fender bulge <NUM> and each bottom fender bulge <NUM> may have a boss-like bulged structure, which may be formed by stamping at corresponding positions on the top fender <NUM> and the bottom fender <NUM>.

As shown in the <FIG>, a section of the top fender <NUM> shows an inverted U shape, and in order to further improve the structural strength at each connecting hole, a support pipe <NUM> is also clamped between the top fender <NUM> and the bottom fender <NUM> corresponding to each connecting hole. The support pipe <NUM> uses an ordinary steel pipe, which may be welded at each bottom fender bulge <NUM> of the bottom fender <NUM> and then, is fixed between the top fender and the bottom fender along, while being welded between the top fender <NUM> and the bottom fender <NUM>.

In the embodiment, the top fender <NUM> may be formed by a mono-block sheet metal, which is the same as the bottom fender <NUM>. However, as a preferred embodiment, the specific design of the embodiment makes that the top fender <NUM> includes a straight middle connecting panel <NUM>, and an upper left panel <NUM> and an upper right panel <NUM> which are fixedly connected to two ends of the middle connecting panel <NUM>. Wherein, the middle connecting plate <NUM> is in welded connection with the upper left panel and the upper right panel, and the rear sub-frame connecting holes <NUM> are distributed in the upper left panel <NUM> and the upper right panel <NUM> on two ends. The top fender <NUM> uses the structure form consisting of the middle connecting panel <NUM>, the upper left panel <NUM> and the upper right panel <NUM>, so that the whole top fender <NUM> is easier to form on the basis of obtaining the straight middle connecting panel <NUM>. And the convenience of the forming is more significant in bifurcated structures on one end of the upper left panel and one end of the upper right panel as described below.

As the bottom fender <NUM> is used as a structural basis in the whole bottom fender body, in order to further improve the structural strength of the bottom fender <NUM>, a bulged reinforcing rib <NUM> is also formed on the bottom fender <NUM> in the embodiment; and as shown in <FIG>, the reinforcing rib <NUM> may extend on the bottom fender <NUM>, so that at least part of bottom fender bulges <NUM> on the bottom fender <NUM> are connected together. Meanwhile, the upper left panel <NUM> and the upper right panel <NUM> in the top fender <NUM> are also consistent with the extension structure of the reinforcing rib <NUM> on the bottom fender <NUM>, so that one end of the upper left panel and one end of the upper right panel are in bifurcated forms.

In the embodiment, as a preferred embodiment of an overall protective structure, the bottom fender body is provided with a linear first edge <NUM> which is located on one side of each rear battery pack connecting part, and a second edge <NUM> which is located on one side of each rear sub-frame connecting part and extends to be connected with two ends of the first edge <NUM> in the overall design; and the second edge <NUM> is in an arc shape. Meanwhile, the top fender <NUM> is flushed with the bottom fender <NUM> at the first edge <NUM>, the bottom fender <NUM> extends outwards against the top fender <NUM> at the second edge <NUM>, so that an edge of the top fender <NUM>, corresponding to the second edge <NUM>, locates inside of the bottom fender <NUM>.

In terms of the overhanging of the bottom fender <NUM> corresponding to one side of the second edge <NUM>, a flange <NUM> is constructed on an overhang edge of the bottom fender <NUM>; the flange <NUM>, for example, may be divided into segments at intervals along an arc edge of the bottom fender <NUM>; and the flange <NUM> is constructed in the middle of the second edge <NUM>. It should be noted that an up-dip bulged part <NUM> is also arranged at the flange <NUM> located in the middle of the second edge <NUM>. Due to the arrangement of the bulged part <NUM>, the probability of the damage of the curb stones to the battery pack <NUM> may be reduced during reversing, which will be described in details as follows.

In the embodiment, as a preferred structural form, a bulged dimension of the bulged part <NUM> may be reduced gradually from the middle to the both sides, as shown in <FIG>. In addition, a plurality of drain holes <NUM> are constructed on the bottom fender <NUM> in the embodiment, and a planar lifting contact part <NUM> is also formed on the bottom fender <NUM> corresponding to the middle connecting panel <NUM>. The lifting contact part <NUM> is a plane which is formed in the middle of the bottom fender <NUM>; and the plane is aligned with the straight middle connecting panel <NUM> from top to bottom, so that the structural stiffness of the lifting contact part <NUM> may be improved to ensure safety during lifting.

In addition, it should be illustrated that as a preferred arrangement form, a bottom surface of the rear battery pack bottom fender <NUM> is a down-dip form along the direction from the tail to the head of the vehicle, that is, the direction from the rear sub-frame assembly <NUM> to the battery pack <NUM>, as shown in the <FIG>. By the inclined arrangement, the vehicle may overcome bellying conditions of curb stones or big stones to put over smoothly, thereby avoiding the frontal collision during reversing.

In the embodiment, with the better structural strength, the rear battery pack bottom fender <NUM> may provide a comprehensive protection on the rear end of the battery pack <NUM> using the expansion protection between the rear sub-frame assembly <NUM> and the battery pack <NUM>. Stagnant water flowing into the rear battery pack bottom fender <NUM> may be drained in time in combination with the inclined arrangement of the rear battery pack bottom fender <NUM> on the basis of the arrangement of the drain holes <NUM> in the bottom fender <NUM>, which may reduce the risks of the rusting of a protective structure.

In addition, as shown in the <FIG>, taking the fall-off and reversing conditions of the vehicle as instances, in case of the fall-off condition of the vehicle, the rear battery pack bottom fender <NUM> may effectively protect the rear end of the battery pack <NUM> against damage when coming into contact with obstacles, such as posts and piles after rear wheels of the vehicle fall to the ground across an abrupt slope. During the curb stones condition of reversing of the vehicle, in case of with a design mode of the rear battery pack bottom fender <NUM> which is arranged lower at first and higher in the end, and especially the design of an outer bulge <NUM> at a middle flange <NUM>, a structural body <NUM> and the tail of the vehicle may be lifted up to achieve guiding the curb stones to go forward , thereby protecting the vehicle against the collision of the curb stones.

In the embodiment, the chassis collision structure utilizes the front lower collision beam assembly <NUM>, the front sub-frame assembly <NUM>, the front battery pack bottom fender <NUM>, the rear battery pack bottom fender <NUM>, and the rear sub-frame assembly <NUM> arranged sequentially along the length direction of the vehicle, so that the front lower collision beam assembly <NUM>, the front sub-frame assembly <NUM>, and the front battery pack bottom fender <NUM> are connected together, the rear battery pack bottom fender <NUM> is connected with the rear sub-frame assembly <NUM>, meanwhile the battery pack <NUM> may also be connected to the front battery pack bottom fender and the rear battery pack bottom fender, so that an collision system which is located at the vehicle chassis may be formed utilizing the above structures in combination with the battery pack <NUM> connected therewith.

Claim 1:
A chassis collision structure of a new energy vehicle, wherein the chassis collision structure of a new energy vehicle comprises a front lower collision beam assembly (<NUM>), a front sub-frame assembly (<NUM>), a front battery pack bottom protective plate (<NUM>), a rear battery pack bottom protective plate (<NUM>), and a rear sub-frame assembly (<NUM>) which are arranged sequentially along a direction from a head to a tail of the vehicle, wherein the front lower collision beam assembly (<NUM>) is connected to a front end of the front sub-frame assembly (<NUM>); the front battery pack bottom protective plate (<NUM>) is connected to a bottom of the front sub-frame assembly (<NUM>); the rear battery pack bottom protective plate (<NUM>) is connected to a bottom of the rear sub-frame assembly (<NUM>); and connecting parts which are connected with a battery pack (<NUM>) are arranged at one end of the front battery pack bottom protective plate (<NUM>) and one end of the rear battery pack bottom protective plate (<NUM>), which are close to each other, respectively,
characterized in that the rear battery pack bottom protective plate (<NUM>) comprises a bottom protective plate body which consists of a top protective plate (<NUM>) and a bottom protective plate (<NUM>) which are buckled fixedly from top to bottom; a plurality of rear battery pack connecting parts (<NUM>) are arranged on one side of the bottom protective plate body, and a plurality of rear sub-frame connecting parts which are connected with the rear sub-frame assembly (<NUM>) are constructed on the other side of the bottom protective plate body with respect to the rear battery pack connecting parts (<NUM>); and the rear battery pack connecting parts (<NUM>) and the rear sub-frame connecting parts are connecting holes which are formed in the bottom protective plate body.