Vehicle body chassis structure of electric vehicle

Abstract

The utility model discloses a vehicle body chassis structure of an electric vehicle, which comprises two longitudinal beams arranged at an interval, a front cross beam and a rear cross beam are respectively arranged at two ends of the two longitudinal beams in a bridging manner, a battery pack mounting cavity is defined by the front cross beam, the two longitudinal beams and the rear cross beam, and a battery pack mounting plate is arranged at the bottom of the battery pack mounting cavity. A battery pack cover plate is arranged at the top of the battery cavity mounting cavity, a liquid cooling pipeline is arranged in the longitudinal beam, a heat dissipation fin plate corresponding to the liquid cooling pipeline is arranged on the side, facing the battery plate mounting cavity, of the longitudinal beam, and the liquid cooling pipeline is communicated with a refrigerating system of the electric logistics vehicle. The battery pack has the advantages that reliable heat dissipation of the battery pack is realized, and a special cooling source does not need to be arranged for the battery; the front cross beam, the two longitudinal beams and the rear cross beam serve as supports and are matched with the battery pack cover plate and the battery pack mounting plate to form a mounting cavity wrapping the battery pack, the battery pack can be protected, the longitudinal beams, the front cross beam and the rear cross beam can provide a reliable supporting effect and an anti-collision effect, and the safety of the battery pack is protected.

Description

Technical Field

[0001] The present application relates to the field of automobile technology, and in particular to a body chassis structure of an electric vehicle. Background Art

[0002] In order to facilitate operation and save energy and reduce emissions, pure electric vehicles are widely used. On-board batteries are used as the power source of electric vehicles. Most of the high-power and long-endurance batteries use battery packs connected in series or in parallel. Electric vehicles are divided into rail vehicles and trackless vehicles according to different usage methods. Trackless vehicles require circuits to plan the transportation path of the vehicle, avoid obstacles, and conduct unified dispatch. The speed is generally slower, and unlike the brush conduction form of trams, the power of trackless vehicles is generally battery packs. In the prior art, there is a setting form in which the batteries are arranged on both sides of the chassis to achieve air cooling, such as a new pure electric vehicle chassis with patent number CN201721550791.0 authorized and announced on June 5, 2018; it includes a high-voltage distribution box, a three-in-one controller, a frame assembly, an electric air compressor, an air-conditioning compressor, a motor controller, a powertrain, a PTC water heater, a cooling water pump, an electric steering oil pump and a battery frame system; the electric air compressor, the air-conditioning compressor, the electric steering oil pump, the PTC water heater and the cooling water pump are arranged under the cab and on the inside of the frame assembly, and integrated on the front end bracket; the high-voltage distribution box, the three-in-one controller and the motor controller are arranged in three layers on the rear end combination bracket; the powertrain is fixed to the inside of the frame assembly; the battery frame system is connected to the ventral surface of the frame assembly; and an attempt is made to achieve battery air cooling by externalizing the battery pack. However, the greater the battery power, the greater the heat it generates. During long-term operation, there is a problem of over-high temperature and easy burns. Obviously, a special cooling system needs to be equipped for the battery pack. However, the cooling method of the battery pack in the prior art is usually an independently set air cooling system, such as a pure electric vehicle cooling device with patent number CN201820428145.5 authorized and announced on November 20, 2018, which involves the field of electric vehicle battery cooling. It includes a square ventilation duct, a battery box body and a group of heat dissipation tubes. A fan is provided at one end of the exhaust port of the square ventilation duct, and a battery box body is installed at the bottom of the square ventilation duct. Hole, a cover body is movably provided at the bottom of the battery box body, a plurality of battery pack mounting slots and a plurality of heat dissipation channels are respectively provided in the battery box body, the plurality of battery pack mounting slots and the plurality of heat dissipation channels are arranged alternately, an air guide elbow is provided at the top opening of the heat dissipation tube, and an arc-shaped guide plate is provided at the bottom opening of the heat dissipation tube. The shortcomings of the prior art are that a special heat dissipation system is required to correspond to the battery pack, which consumes a lot of energy; the air cooling form of the battery pack requires a special shell to protect the battery pack, and the structure occupies a large area; the battery pack is easily damaged by collision, and the impact resistance reliability of the battery pack must be considered, resulting in great technical difficulty in setting the battery pack. Utility Model Content

[0003] Based on the above-mentioned deficiencies in the prior art, the utility model provides a body chassis structure of an electric vehicle, which can improve the cooling efficiency of the battery of the electric vehicle, and does not require a special cooling source to be provided for the battery. It can also protect the battery pack so that the battery pack can be directly used without external packaging, thereby realizing the integration of the battery pack outer shell and the heat dissipation structure on the vehicle body.

[0004] In order to achieve the above-mentioned utility model purpose, the utility model adopts the following technical solutions.

[0005] A body chassis structure of an electric vehicle comprises two longitudinal beams arranged at intervals, a front cross beam and a rear cross beam are respectively spanned at both ends of the two longitudinal beams, a battery pack installation cavity is formed by the front cross beam, the two longitudinal beams and the rear cross beam, a battery pack installation plate is provided at the bottom of the battery pack installation cavity, a battery pack cover plate is provided at the top of the battery cavity installation cavity, a liquid cooling pipe is provided inside the longitudinal beam, a heat absorbing fin plate corresponding to the liquid cooling pipe is provided on the side of the longitudinal beam facing the battery plate installation cavity, and the liquid cooling pipe is connected to the refrigeration system of the electric vehicle.

[0006] The refrigeration system is bypassed through a liquid cooling pipe, and the low-temperature medium of the refrigeration system is used to cool the inside of the longitudinal beam. As a heat-absorbing fin is provided inside the longitudinal beam corresponding to the battery pack installation cavity, the heat of the battery pack installation cavity can be convected to the liquid cooling pipe through the heat-absorbing fin, thereby realizing reliable heat dissipation of the battery pack, without the need to equip the battery with a special cooling source; the front crossbeam, two longitudinal beams and the rear crossbeam serve as supports, and cooperate with the battery pack cover and the battery pack mounting plate to form an installation cavity covering the battery pack, which can protect the battery pack; the longitudinal beam, front crossbeam and rear crossbeam provide reliable support and anti-collision effects to protect the safety of the battery pack.

[0007] Preferably, the longitudinal beam is provided with a heat-insulating coating on the outer side except the side corresponding to the battery pack installation cavity. The heat-insulating setting on the outside of the longitudinal beam is realized so that the longitudinal beam only completes the heat dissipation of the battery pack installation cavity instead of the overall temperature reduction, thereby achieving the purpose of energy saving.

[0008] Preferably, a connecting beam is provided between the front cross beam and the rear cross beam, and the connecting beam is located in the middle between the two longitudinal beams. The battery pack mounting plate includes a plurality of mounting plate units, and the two ends of the mounting plate units are respectively connected across the connecting beam and the longitudinal beam, and the adjacent mounting plate units are riveted. The mounting plate units are connected in sequence to form a riveted seal to ensure the protection of the battery pack; the connecting beam improves the overall structural strength of the chassis structure.

[0009] Preferably, a heat-insulating waterproof pad is fixedly provided on the outer side of the battery pack mounting plate toward the bottom. The heat-insulating waterproof pad can ensure the heat insulation performance of the bottom of the chassis structure, prevent the high temperature of the external road surface from affecting the battery pack, and prevent the ground water from penetrating into the battery pack, thereby improving the safety of the battery pack installation.

[0010] Preferably, a chassis is provided on the upper side of the battery pack installation cavity, and the longitudinal beam, front cross beam and rear cross beam are fixedly arranged on the lower side of the chassis. A refrigeration system is arranged on the chassis, and a cooling gap is arranged between the chassis and the battery pack installation cavity, and a cooling circuit connected to the refrigeration system is arranged in the cooling gap. The refrigeration system is a water cooling system, including a condenser, a compressor, an expansion valve and a heat exchanger, which can exchange heat to cool hot water to form cooling water. Through the cooling water and the cooling circuit, the heat dissipation in the battery pack installation cavity is realized in the lateral direction, thereby improving the heat dissipation efficiency of the battery pack; the chassis structure is arranged as an extension structure of the chassis, and can be disassembled, repaired and replaced as a whole. When the logistics task is heavy, the chassis structure can be disassembled and replaced as a whole, eliminating the waiting time for charging and improving the logistics transportation efficiency of the vehicle.

[0011] Preferably, the battery pack cover includes a horizontally arranged cover unit and a U-shaped groove between adjacent cover units, and the cooling pipe is arranged in the U-shaped groove. The U-shaped groove plays a role in restraining and limiting the cooling pipe, which can not only ensure the heat dissipation of the battery pack, but also ensure the shockproofness of the cooling circuit setting.

[0012] Preferably, the cross-section of the longitudinal beam is a rectangular shape with a notch, a closed wall is arranged at the position of the longitudinal beam corresponding to the notch, and the liquid cooling pipe is arranged at the center of the longitudinal beam. The notch extends to the wall of the liquid cooling pipe, which can facilitate the observation of the setting shape of the liquid cooling pipe, and is more convenient for the installation of the liquid cooling pipe than the closed longitudinal beam cross-section.

[0013] Preferably, the edge of the battery pack cover is provided with a convex shoulder portion that matches the closed wall of the longitudinal beam. The convex shoulder portion realizes the constraint of the battery pack cover plate corresponding to the longitudinal beam, and at the same time can realize the transfer of the refrigerant environment of the battery pack cover plate to the upper side of the battery pack installation cavity, thereby improving the heat dissipation efficiency of the battery pack installation cavity.

[0014] The utility model has the following beneficial effects: it can improve the battery cooling efficiency of the electric vehicle, and there is no need to equip the battery with a special cooling source. It can also protect the battery pack so that the battery pack can be directly used without external packaging, thereby realizing the integration of the battery pack outer shell and the heat dissipation structure on the vehicle body. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a structural schematic diagram of the utility model.

[0016] Figure 2 It is an internal sectional view after the utility model is assembled with the chassis.

[0017] Figure 3 It is a transverse sectional view of the longitudinal beam in the utility model.

[0018] In the figure: longitudinal beam 1 front cross beam 2 rear cross beam 3 connecting beam 4 battery pack installation cavity 5 heat insulation and waterproof pad 6 battery pack cover 7 shoulder 8 liquid cooling pipe 9 closed wall 10 heat absorbing fin plate 11 heat insulation coating 12 chassis 13 refrigeration system 14 cooling gap 15 cooling pipe 16 U-shaped groove 17 battery pack installation plate 18. DETAILED DESCRIPTION

[0019] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0020] Embodiment 1,

[0021] like Figures 1 to 3 As shown, a body chassis structure of an electric vehicle includes two longitudinal beams 1 that are spaced apart. The two longitudinal beams 1 are parallel, and the two ends of the two longitudinal beams 1 are respectively spanned by a front crossbeam 2 and a rear crossbeam 3. A connecting beam 4 is provided between the front crossbeam 2 and the rear crossbeam 3. The connecting beam 4 is located in the middle between the two longitudinal beams 1, and the connecting beam 4 is parallel to the longitudinal beams 1. A battery pack mounting cavity 5 is formed by the front crossbeam 2, the two longitudinal beams 1 and the rear crossbeam 3. A battery pack mounting plate 18 is provided at the bottom of the battery pack mounting cavity 5. The battery pack mounting plate 18 includes a plurality of mounting plate units. The two ends of the mounting plate units are respectively spanned by the connecting beam 4 and the longitudinal beam 1, and the adjacent mounting plate units are riveted. Vertical plates are provided between adjacent mounting plate units to divide the battery pack mounting cavity 5 into unit intervals corresponding to individual battery packs, so that the battery packs will not be arranged close to each other, and can play an independent protection and restraint role for the battery packs. A heat-insulating and waterproof pad 6 is fixedly provided on the outside of the bottom of the battery pack mounting plate 18. As shown Figure 2 As shown, the heat-insulating and waterproof pad 6 is located on the bottom outer end surface of the battery pack mounting plate 18. The top of the battery pack mounting cavity is provided with a battery pack cover plate 7, and a liquid cooling pipe 9 is provided inside the longitudinal beam 1. The cross-sectional shape of the longitudinal beam 1 is a rectangular with a notch. The longitudinal beam 1 is provided with a closed wall surface 10 at the position corresponding to the notch, and the liquid cooling pipe 9 is provided at the center of the longitudinal beam 1. The edge of the battery pack cover plate 7 is provided with a convex shoulder portion 8 that matches the closed wall surface 10 of the longitudinal beam 1.

[0022] The side of the longitudinal beam 1 facing the battery panel installation cavity is provided with a heat-absorbing fin plate 11 corresponding to the liquid cooling pipe 9. The heat-absorbing fin plate 11 is provided with a plurality of pieces, and the plurality of heat-absorbing fin plates 11 are arranged in a radial shape. The liquid cooling pipe 9 is connected to the refrigeration system 14 of the electric vehicle. The refrigeration system 14 is a water cooling system, including a condenser, a compressor, an expansion valve and a heat exchanger, which can exchange heat to cool hot water to form cooling water. The refrigeration system 14 used in this application is the same as the refrigeration system 14 of a conventional electric vehicle, so the specific pipeline structure will not be elaborated. The longitudinal beam 1 is provided with a thermal insulation coating 12 on the outer side surfaces except the side surface corresponding to the battery pack installation cavity 5. The triangle formed by the outer side wall and the lower side wall of the longitudinal beam 1 is a solid structure to ensure the supporting capacity of the longitudinal beam 1. Half of the wall surface of the liquid cooling water pipe is welded to the solid structure, and the thermal insulation coating 12 is provided on the outer side wall and the lower side wall of the longitudinal beam 1.

[0023] A chassis 13 is arranged on the upper side of the battery pack mounting cavity, and the longitudinal beam 1, the front cross beam 2 and the rear cross beam 3 are fixedly arranged on the lower side of the chassis 13. A refrigeration system 14 is arranged on the chassis 13. A cooling gap 15 is arranged between the chassis 13 and the battery pack mounting cavity 5. A cooling circuit composed of a cooling pipe 16 connected to the refrigeration system 14 is arranged in the cooling gap 15. The battery pack cover plate 7 includes a horizontally arranged cover plate unit and a U-shaped groove 17 located between adjacent cover plate units, and the cooling pipe 16 is arranged in the U-shaped groove 17. The U-shaped groove 17 protrudes downward into the battery pack mounting cavity 5. The chassis 13 is the body chassis 13 of the electric vehicle. In addition to the refrigeration system 14, the chassis 13 is also provided with drive wheels, drive motors, motor controllers, etc. The chassis 13 and the corresponding vehicle components thereon are prior art, and therefore will not be expanded.

[0024] The present application bypasses the refrigeration system 14 through the liquid cooling pipe 9, and uses the low-temperature medium of the refrigeration system 14 to cool the inside of the longitudinal beam 1. Since the heat-absorbing fin plate 11 is set inside the longitudinal beam 1 corresponding to the battery pack installation cavity 5, the heat of the battery pack installation cavity 5 can be transferred to the liquid cooling pipe 9 through the heat-absorbing fin plate 11 to achieve reliable heat dissipation of the battery pack, and there is no need to equip the battery with a special cooling source; the front crossbeam 2, the two longitudinal beams 1 and the rear crossbeam 3 are used as supports, and the battery pack cover plate 7 and the battery pack installation plate 18 are used to form an installation cavity covering the battery pack, which can protect the battery pack. The longitudinal beam 1, the front crossbeam 2 and the rear crossbeam 3 provide reliable support and anti-collision effects to protect the safety of the battery pack, so that the battery pack can be directly used without external packaging, and the battery pack outer shell and the heat dissipation structure are integrated on the vehicle body. The chassis structure is set as an extension structure of the chassis 13, which can be disassembled, repaired and replaced as a whole. When the logistics task is heavy, the chassis structure can be disassembled and replaced as a whole, eliminating the waiting time for charging and improving the logistics transportation efficiency of the vehicle.

Claims

1. A body chassis structure of an electric vehicle, characterized in that: It includes two longitudinal beams arranged at intervals, a front cross beam and a rear cross beam are respectively spanned at both ends of the two longitudinal beams, a battery pack installation cavity is formed by the front cross beam, the two longitudinal beams and the rear cross beam, a battery pack installation plate is provided at the bottom of the battery pack installation cavity, a battery pack cover plate is provided at the top of the battery cavity installation cavity, a liquid cooling pipe is provided inside the longitudinal beam, a heat-absorbing fin plate corresponding to the liquid cooling pipe is provided on the side of the longitudinal beam facing the battery panel installation cavity, and the liquid cooling pipe is connected to a refrigeration system of an electric vehicle.

2. The vehicle chassis structure of an electric vehicle according to claim 1, characterized in that: The outer side surfaces of the longitudinal beam except the side surfaces corresponding to the battery pack installation cavity are provided with a heat insulation coating.

3. The vehicle chassis structure of an electric vehicle according to claim 1, characterized in that: A connecting beam is provided between the front cross beam and the rear cross beam, and the connecting beam is located in the middle position between the two longitudinal beams. The battery pack mounting plate includes a plurality of mounting plate units, and the two ends of the mounting plate units are respectively bridged over the connecting beam and the longitudinal beam, and adjacent mounting plate units are riveted.

4. The vehicle chassis structure of an electric vehicle according to claim 1, characterized in that: The battery pack mounting plate is fixedly provided with a heat-insulating and waterproof pad on the outer side facing the bottom.

5. The vehicle chassis structure of an electric vehicle according to claim 1, characterized in that: A chassis is provided on the upper side of the battery pack mounting cavity, and a longitudinal beam, a front cross beam and a rear cross beam are fixedly arranged on the lower side of the chassis. A refrigeration system is arranged on the chassis, and a cooling gap is provided between the chassis and the battery pack mounting cavity. A cooling circuit composed of cooling pipes connected to the refrigeration system is provided in the cooling gap.

6. The vehicle chassis structure of an electric vehicle according to claim 5, characterized in that: The battery pack cover plate includes a horizontally arranged cover plate unit and a U-shaped groove located between adjacent cover plate units, and the cooling pipe is arranged in the U-shaped groove.

7. The vehicle chassis structure of an electric vehicle according to claim 1, characterized in that: The cross-section of the longitudinal beam is a rectangular shape with a notch, a closed wall surface is arranged at a position of the longitudinal beam corresponding to the notch, and a liquid cooling pipe is arranged at a center position of the longitudinal beam.

8. The vehicle chassis structure of an electric vehicle according to claim 7, characterized in that: The edge of the battery pack cover is provided with a convex shoulder portion that matches the closed wall surface of the longitudinal beam.

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