CCB-based connecting structure of sliding plate chassis and semi-bearing type vehicle body and sealing method thereof

Abstract

The invention discloses a sliding plate chassis and semi-bearing type vehicle body connecting structure based on a CCB technology and a sealing method. The sliding plate chassis module is formed by connecting a front module, a middle module and a rear module through a V-shaped structure, magnesium alloy die-casting forming is conducted through a 3000-4000 ton die-casting machine, the modules are connected through laser-double-arc three-beam composite welding, the middle module is integrated with a fishbone-shaped power battery frame, and a detachable bumper is arranged on the side to achieve battery replacement. A cabin and a front cabin module of the semi-bearing type vehicle body are detachably connected with a middle module and a front module of a chassis respectively, and a connecting interface is sealed through a plurality of layers of sealing gaskets, waterproof rubber strips and the like. According to the structure, the problems of large equipment investment, high maintenance cost, low production flexibility and the like in the prior art are solved, the manufacturing cost is reduced, the modular customization and maintenance economy is improved, and rapid battery replacement and efficient sealing are achieved.

Description

Technical Field

[0001] The present invention provides a connection structure and a sealing method thereof, and particularly relates to a connection structure between a skateboard chassis and a semi-load-bearing vehicle body based on a CCB and a sealing method thereof. Background Art

[0002] As the core load-bearing platform for new energy vehicles, the skateboard chassis integrates the battery, drive, and suspension systems, and realizes the overall vehicle functionality through connection with the vehicle body. Existing technologies primarily utilize an integrated die-cast structure (such as Tesla's solution) or CTC / CTB technology (such as BYD's solution), with the load carried by the monolithic body or chassis. While these devices can ensure structural rigidity, they have two major limitations:

[0003] Manufacturing: Integrated die-casting requires a die-casting machine of more than 9,000 tons, which requires huge equipment investment and is difficult to adapt to customized iterations;

[0004] Maintenance: When a vehicle is damaged by a collision, the chassis or body needs to be replaced as a whole, which is not economical.

[0005] In the existing connection structure between the skateboard chassis and the body, the chassis and the body are both inseparable, resulting in low production flexibility and high maintenance costs; the connection interface relies on simple bolt fixation and lacks a sealing solution for modular separation design, which can easily cause water leakage or insufficient rigidity. Summary of the Invention

[0006] In order to solve the above problems, this application provides a CCB-based skateboard chassis and semi-load-bearing body connection structure and a sealing method thereof, which solves the problems of modular production and maintenance, realizes the connection between the three-section chassis die-casting and the detachable body, improves the waterproofness and rigidity through multi-layer sealing components and composite welding technology, reduces equipment costs and supports customized iteration.

[0007] In order to solve the above technical problems, the present invention provides the following technical solutions: a skateboard chassis and semi-load-bearing vehicle body connection structure based on CCB technology, comprising:

[0008] Skateboard chassis module: It is composed of a front module, a middle module, and a rear module connected by a V-shaped structure. Horizontal positioning pins are used to achieve 2D horizontal assembly positioning between the front module and the middle module, and between the middle module and the rear module.

[0009] Semi-load-bearing vehicle body: comprising a separate cockpit module and a front cabin module, wherein the cockpit module is detachably connected to the middle module of the skateboard chassis via a first connecting mechanism, and the front cabin module is detachably connected to the front module of the skateboard chassis via a second connecting mechanism;

[0010] Sealing component: It is installed at the connection interface between the cockpit module and the middle module, and between the front cabin module and the front module, and uses multi-layer sealing gaskets and waterproof strips to achieve sealing.

[0011] Preferably, the V-shaped structure is connected in the following manner: the joint surface between the front module and the middle module is at a V-shaped bevel, and is fixed by laser-arc hybrid welding; the joint surface between the middle module and the rear module is at a V-shaped bevel, and is fixed by laser-arc hybrid welding; the horizontal positioning pins are arranged at the four corners of the V-shaped joint surface to constrain the forces in the X and Y directions.

[0012] Preferably: the sealing method of the sealing assembly includes: laying an annular sealing gasket at the connection interface between the cockpit module and the middle module, and injecting waterproof sealant around the bolt hole; setting a U-shaped waterproof rubber strip at the connection interface between the front cabin module and the front module, and filling the inside of the rubber strip with foam sealing material; all wiring harness through-holes are double-sealed with rubber sheath + heat shrink tube.

[0013] Preferably: the middle module integrates a fishbone-shaped power battery frame, its high-voltage wiring harness is arranged in the middle cavity of the fishbone, and the low-voltage wiring harness is arranged along both sides of the fishbone; the front module and the rear module respectively accommodate the drive unit and the suspension system.

[0014] Preferably, the skateboard chassis adopts a three-section magnesium alloy die-cast frame: the front module, the middle module, and the rear module are all die-cast separately by a 3000-4000 ton die-casting machine; the modules are connected by laser-double arc three-beam hybrid welding, and the welding parameters are: laser power 4kW, MIG current 150A (Al-Si welding wire), TIG current 100A (AC mode).

[0015] Preferably: it also includes a side replacement structure: a detachable anti-collision bar is set on the side wall of the module in the skateboard chassis;

[0016] The battery replacement interface is integrated on the inside of the bumper, and the battery replacement path is exposed after the bumper is removed.

[0017] Furthermore, a method for sealing a skateboard chassis and a semi-load-bearing vehicle body based on CCB technology includes the following steps:

[0018] Apply thermally conductive sealant to the connecting flange surfaces between the skateboard chassis and the front cabin module and cockpit module;

[0019] Install multi-layer composite sealing gaskets with a thickness of 2–3 mm;

[0020] The connection interface is locked by high-strength bolts with a bolt preload of 80–100 N·m;

[0021] Cover the bolt heads with sealing caps and spray polyurethane waterproof coating on the joints.

[0022] One or more technical solutions provided in the embodiments of this application have at least the following technical effects or advantages:

[0023] This device adopts a three-section magnesium alloy die-casting frame and replaces equipment of more than 9,000 tons with a 3,000-4,000-ton die-casting machine, reducing the equipment investment and cost on the manufacturing side. The modular design can realize 2D horizontal assembly positioning through the V-shaped structure connection of the front, middle and rear modules and the horizontal positioning pins, and supports skateboard chassis combinations with different power forms such as front-wheel drive, rear-wheel drive and four-wheel drive to meet customized iteration needs. The maintenance side uses modular design, and only the damaged module (such as the front cabin module) needs to be replaced in the event of a collision, avoiding the overall replacement of the chassis or body. At the same time, the middle module integrates a fishbone-shaped power The battery frame is equipped with a side-swap battery structure and a detachable bumper to improve maintenance economy. In terms of connection structure, the cockpit module and the front cabin module of the semi-load-bearing body are detachably connected to the middle module and the front module of the skateboard chassis respectively, and multi-layer sealing gaskets, waterproof strips and laser-arc composite welding technology are used to solve the problems of insufficient sealing and rigidity of the existing connection interface. In addition, the distributed manufacturing model, the module assembly with a pure electric and hybrid commonality rate of over 90%, and the cockpit and front cabin separation technology further reduce manufacturing costs, shorten the development cycle, and improve production flexibility and safety performance.

[0024] Other advantages, objects and features of the present invention will be described in part in the following description and, in part, will be apparent to those skilled in the art based on an examination of the following or may be learned from the practice of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic diagram of a connection structure between a skateboard chassis and a semi-load-bearing vehicle body based on CCB technology of the present invention;

[0026] Figure 2 A schematic diagram of the positioning pin arrangement for controlling 2D horizontal assembly of the front and middle sections of a skateboard chassis and a semi-load-bearing vehicle body connection structure based on CCB technology according to the present invention;

[0027] Figure 3 A schematic diagram of the positioning pin arrangement for controlling 2D horizontal assembly in the middle and rear sections of a connection structure between a skateboard chassis and a semi-load-bearing vehicle body based on CCB technology of the present invention;

[0028] Figure 4 This is a timing diagram of the assembly of a three-section magnesium alloy chassis module for a method of connecting and sealing a skateboard chassis and a semi-load-bearing vehicle body based on CCB technology of the present invention;

[0029] Figure 5 This is a timing diagram of the semi-load-bearing vehicle body connection of a method for connecting and sealing a skateboard chassis and a semi-load-bearing vehicle body based on CCB technology of the present invention. DETAILED DESCRIPTION

[0030] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0031] It should be noted that the terms “vertical”, “horizontal”, “up”, “down”, “left”, “right” and similar expressions used in this document are for illustrative purposes only and do not represent the only implementation method.

[0032] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this invention pertains; the terms used herein in the specification of the present invention are for the purpose of describing specific embodiments only and are not intended to limit the present invention; the term "and / or" used herein includes any and all combinations of one or more of the associated listed items.

[0033] like Figure 1 、 2 As shown in Figure 3, a skateboard chassis and semi-monocoque body connection structure based on CCB technology consists of a skateboard chassis module, a semi-monocoque body, and a sealing assembly. The skateboard chassis module is composed of front, middle, and rear modules connected in a V-shaped structure, with horizontal locating pins used to achieve 2D horizontal assembly positioning. It uses a three-section magnesium alloy die-cast frame, which is die-cast in separate sections using a 3000-4000 ton die-casting machine. The modules are connected using laser-double arc three-beam hybrid welding. The cabin module and front cabin module of the semi-monocoque body are detachably connected to the middle and front modules of the skateboard chassis, respectively. The skateboard chassis middle module integrates a fishbone-shaped power battery frame, while the front and rear modules house the drive unit and suspension system, and also feature a side-mounted battery replacement structure.

[0034] In this implementation scheme, the three-section magnesium alloy die-casting frame is connected by a V-shaped structure and the horizontal positioning pins to constrain the X / Y force, so that the tonnage of the die-casting machine is reduced from 9,000 tons to 3,000-4,000 tons, which greatly reduces the equipment investment and manufacturing costs. The modular design supports 9 types of skateboard chassis combinations such as front-wheel drive / rear-wheel drive / four-wheel drive (such as 5 types of front-wheel drive pure electric combinations and 4 types of rear-wheel drive pure electric combinations), and achieves maximum commonality through the minimum number of modules to meet customized iteration requirements; the detachable connection structure of the semi-load-bearing body only requires replacing the front cabin module or the cockpit module in the event of collision damage, avoiding the overall replacement of the chassis, and improving maintenance economy. Improvement; The fishbone-shaped power battery frame adopts a nine-square structure with a magnesium alloy die-cast fish head and tail and an aluminum alloy profile fish body. The wheelbase can be flexibly adjusted through laser composite welding, and the crossbeams and longitudinal beams form a secondary collision protection. Combined with the side battery replacement structure (the anti-collision bar is removed to expose the battery replacement path), it not only improves battery safety but also supports fast battery replacement; the combination of multi-layer sealing components and composite welding technology solves the problems of water leakage and insufficient rigidity of traditional bolt connections, and the distributed manufacturing model and the 90% commonality rate of pure electric / hybrid further shorten the vehicle development cycle by 50% and reduce R&D costs by 70%, achieving a double breakthrough in production flexibility and safety performance.

[0035] like Figure 4 and Figure 5 As shown in the figure, the connection sealing method is to first apply thermal conductive sealant to the connection flange surfaces between the skateboard chassis and the front cabin module and the cockpit module, install a 2-3mm thick multi-layer composite sealing gasket, and then lock the connection interface with a pre-tightening force of 80-100N·m using high-strength bolts. After that, the bolt head is covered with a sealing cap, and a polyurethane waterproof coating is sprayed on the joint. In addition, the sealing component also uses multi-layer sealing gaskets, waterproof strips, rubber sheaths + heat shrink tubing, etc. to achieve effective sealing at different connection interfaces.

[0036] In this embodiment, based on the above technical solution, the implementation and implementation steps of the present invention are systematically described below:

[0037] Chassis module combination

[0038] Pure electric drive: front-wheel drive (5 combinations), rear-wheel drive (4 combinations), four-wheel drive (4 combinations)

[0039] Hybrid drive:

[0040] PHEV hydrogen-electric hybrid: front-wheel drive (5 combinations), four-wheel drive (4 combinations)

[0041] REEV hydrogen range extender: front-wheel drive (5 combinations), four-wheel drive (4 combinations)

[0042] Car body connection solution

[0043] Solution Type Skateboard chassis structure Body type Split body solution Modular skateboard chassis Front cabin + cockpit are separated independently Semi-loaded solution Modular / integrated chassis Semi-load-bearing integrated body Non-load-bearing solution Integrated skateboard chassis Semi- and non-load-bearing hybrid bodies

[0044] Special scenario implementation

[0045] Side battery replacement: remove the side wall anti-collision bar in the middle section of the skateboard chassis → expose the fishbone battery frame battery replacement interface → horizontally replace the battery pack;

[0046] Collision repair: When the front cabin is damaged, only the V-connected front module is removed → replaced with a new one → the mid-rear chassis is reused;

[0047] 2. Implementation Steps

[0048] Phase 1: Chassis Manufacturing

[0049] Split die casting:

[0050] The magnesium alloy chassis modules (front / center / rear) are die-cast in sections using a 3000-4000 ton die-casting machine;

[0051] The middle section integrates the fishbone frame: the fish head / fish tail are made of magnesium alloy die-casting + the fish body is made of nine-square aluminum profile;

[0052] V-type connection:

[0053] Front-center / center-rear modules dock at a 45° angle, with locating pins locking the 2D plane position;

[0054] Laser-arc hybrid welding: laser 4kW + MIG 150A (Al-Si welding wire) welding seam;

[0055] Phase 2: Body Assembly

[0056] Body connection:

[0057] Front compartment module → Bolt fixed to the front chassis connection flange

[0058] Cockpit module → bolted to the top flange of the mid-chassis

[0059] Sealing treatment:

[0060] The connection interface is laid with 2mm multi-layer sealing gasket + U-shaped foam strip

[0061] The wiring harness holes are sealed with a double layer of rubber sheath + heat shrink tube;

[0062] Phase 3: Functional expansion

[0063] Battery standardization:

[0064] The fishbone frame unifies battery specifications (e.g. 145 types → ≤ 58 types), and the horizontal arrangement improves column collision safety.

[0065] Distributed Manufacturing:

[0066] The chassis module, cockpit, and front cabin are produced at separate locations → 2D horizontal assembly is completed at the final site.

[0067] Based on the above content, this embodiment needs to be combined with high-strength bolts in the existing technology (such as 10.9 grade high-strength alloy structural steel bolts) to achieve detachable connection between the cockpit module and the middle module, and between the front cabin module and the front module. The bolt preload force needs to be precisely controlled within the range of 80-100N·m by a torque wrench in the existing technology. The laser-dual arc three-beam hybrid welding process needs to use the Trumpf TruConnect series laser welding equipment in the existing technology (laser power 4kW) in combination with a MIG / TIG welding unit (MIG current 150A, TIG current 100A), and use Al-Si welding wire (such as ER4047) and AC mode film breaking technology. The magnesium alloy die-casting frame uses the AZ91D magnesium alloy material in the existing technology (tensile strength ≥240MPa) and is formed by a 3000-4000 ton Bühler die-casting machine. The fish body part of the aluminum alloy fishbone-shaped power battery frame uses 6061-T6 aluminum alloy profile (yield strength ≥276MPa) and is aging-treated by the existing technology. The treatment process is strengthened; the waterproof strip in the sealing component adopts the EPDM ethylene propylene diene monomer rubber (Shore hardness 60±5A) in the existing technology, and is filled with PU foam sealing material inside. The bolt hole is injected with the single-component silicone sealant (such as Dow Corning 730) in the existing technology. The rubber sheath at the wiring harness through-hole adopts the silicone rubber material in the existing technology (temperature resistant -60℃~200℃) and is combined with polyolefin heat shrink tube (shrinkage ratio 2:1) to achieve double sealing; the anti-collision bar in the side battery replacement structure needs to be connected to the module in the chassis through the hydraulic quick-disassembly mechanism in the existing technology, and the battery replacement interface adopts the GB / T 20234.3-2015 standard charging socket in the existing technology to ensure compatibility with the battery replacement equipment.

[0068] Although the present invention has been disclosed above in terms of preferred embodiments, it is not intended to limit the present invention. Anyone familiar with this technology can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be based on the definition of the claims.

Claims

1. A skateboard chassis and semi-load-bearing vehicle body connection structure based on CCB technology, characterized in that: include: Skateboard chassis module: It is composed of a front module, a middle module, and a rear module connected by a V-shaped structure. Horizontal positioning pins are used between the front module and the middle module, and between the middle module and the rear module to achieve 2D horizontal assembly positioning. Semi-load-bearing vehicle body: comprising a separate cockpit module and a front cabin module, wherein the cockpit module is detachably connected to the middle module of the skateboard chassis via a first connecting mechanism, and the front cabin module is detachably connected to the front module of the skateboard chassis via a second connecting mechanism; Sealing component: It is installed at the connection interface between the cockpit module and the middle module, and between the front cabin module and the front module, and uses multi-layer sealing gaskets and waterproof strips to achieve sealing.

2. The skateboard chassis and semi-load-bearing vehicle body connection structure based on CCB technology according to claim 1, characterized in that: The connection mode of the V-shaped structure is: The joint surface between the front module and the middle module is V-shaped and is fixed by laser-arc hybrid welding; The joint surface between the middle module and the rear module is V-shaped and is fixed by laser-arc hybrid welding; The horizontal positioning pins are arranged at the four corners of the V-shaped joint surface to constrain the forces in the X and Y directions.

3. The skateboard chassis and semi-load-bearing vehicle body connection structure based on CCB technology according to claim 1, characterized in that: The sealing method of the sealing assembly includes: Lay an annular sealing gasket at the connection interface between the cockpit module and the middle module, and inject waterproof sealant around the bolt holes; A U-shaped waterproof strip is provided at the connection interface between the front cabin module and the front module, and the interior of the strip is filled with foam sealing material; All wiring harness holes are double sealed with rubber sheath + heat shrink tube.

4. The skateboard chassis and semi-load-bearing vehicle body connection structure based on CCB technology according to claim 1, characterized in that: The middle module integrates a fishbone-shaped power battery frame, with its high-voltage wiring harness arranged in the middle cavity of the fishbone and the low-voltage wiring harness arranged along both sides of the fishbone; The front module and the rear module respectively accommodate the drive unit and the suspension system.

5. The skateboard chassis and semi-load-bearing vehicle body connection structure based on CCB technology according to claim 1, characterized in that: The skateboard chassis adopts a three-section magnesium alloy die-cast frame: The front module, middle module and rear module are all die-cast separately using a 3000-4000 ton die-casting machine; The modules are connected by laser-double arc three-beam hybrid welding, and the welding parameters are: laser power 4kW, MIG current 150A (Al-Si welding wire), and TIG current 100A (AC mode).

6. The skateboard chassis and semi-load-bearing vehicle body connection structure based on CCB technology according to claim 1, characterized in that: Also includes side-swap structure: The side walls of the modules in the skateboard chassis are provided with detachable anti-collision bars; The battery replacement interface is integrated on the inside of the bumper, and the battery replacement path is exposed after the bumper is removed.

7. A method for connecting and sealing a skateboard chassis and a semi-load-bearing vehicle body based on CCB technology, characterized in that: The following steps are involved: A. Apply thermally conductive sealant to the connecting flange surfaces between the skateboard chassis, the front cabin module, and the cockpit module; B. Install a multi-layer composite sealing gasket with a thickness of 2-3 mm; C. The connection interface is locked by high-strength bolts with a bolt preload of 80–100 N·m; D. Cover the bolt head with a sealing cap and spray a polyurethane waterproof coating on the joints.

Images