Range-extending type electric forklift chassis system

Abstract

The utility model relates to a chassis system of an extended-range electric forklift. The chassis system comprises a frame, a lifting mechanism, a driving cabin and a rear cabin are sequentially arranged on the frame from front to back; an oil tank, an electrical accessory, a power system and a thermal management system are arranged in the rear cabin; a front axle and a rear drive axle are arranged below the frame, the rear drive axle is arranged below the cab, and the front axle is arranged at the bottom end of the front portion of the lifting mechanism. The utility model has the beneficial effects that the chassis system and the lifting working area can be independently placed in space by controlling the layout of the chassis system, so that different functions can be matched on the basis of the same chassis, the development period is shortened, and the cost is reduced; and the environmental adaptability of the forklift is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of fork truck, especially to a range extended electric fork truck chassis system. BACKGROUND

[0002] With the development of economy and the improvement of environmental protection and energy saving requirements, the mainstream fork truck on the market generally adopts a pure electric scheme, but its shortcoming is that only battery power supply is used, and frequent charging is often needed after operation, which easily causes operation downtime and reduces production efficiency.

[0003] The range extended electric vehicle can effectively increase the cruising range by burning the medium to drive the generator, but the system is complex, the development cycle is long, and the cost is high.

[0004] It is found that different types of fork trucks are often needed in factories, and their chassis functions are similar, so it is time-consuming and laborious to develop different chassis for each vehicle, resulting in high vehicle cost. In the automobile industry, the concept of platform is used to assemble parts into standardized modules, and the same set of mature and stable vehicle basic framework is used to adapt to different performance requirements of vehicle models. The fork truck can be designed and developed in a similar way to reduce the cost of the chassis system.

[0005] Therefore, the range extended fork truck chassis system is proposed, which can shorten the development cycle of the fork truck, reduce the cost, and increase the environmental adaptability of the fork truck. UTILITY MODEL CONTENTS

[0006] The utility model aims at overcoming the defects of the prior art, providing a platformized range extended fork truck chassis system, which has a low chassis height, realizes the reduction of the vehicle height, and increases the environmental adaptability of the fork truck. The vehicle can run on electricity or fuel, which improves the cruising ability of the fork truck and improves the work efficiency. One chassis system is applied to different function fork trucks, which shortens the development cycle of the fork truck and reduces the cost.

[0007] The utility model aims at overcoming the defects of the prior art, providing a platformized range extended fork truck chassis system, which has a low chassis height, realizes the reduction of the vehicle height, and increases the environmental adaptability of the fork truck. The vehicle can run on electricity or fuel, which improves the cruising ability of the fork truck and improves the work efficiency. One chassis system is applied to different function fork trucks, which shortens the development cycle of the fork truck and reduces the cost.

[0008] The utility model relates to a range extended electric fork truck chassis system, which comprises a vehicle frame, a lifting mechanism, a driver cabin and a rear engine room arranged in sequence from front to rear on the vehicle frame, an oil tank, electrical accessories, a power system and a thermal management system arranged in the rear engine room, a front axle and a rear drive axle arranged below the vehicle frame, and the rear drive axle is arranged below the driver cabin and the front axle is arranged at the front bottom end of the lifting mechanism.

[0009] In the scheme, the front of the forklift is a lifting system, and the forklift chassis system adopts a rear wheel drive scheme, the drive motor output shaft is connected with the drive axle reducer, so as to completely give out the space at the front end of the forklift; and a rear cabin is arranged behind the cockpit, the counterweight of the rear cabin balances the load of the lifting mechanism, so as to prevent the forklift from being unbalanced. At the same time, the rear wheels also act as steering wheels, and an electric hydraulic power steering system is adopted, and the steering oil cylinder is installed on the rear drive axle.

[0010] In a preferred embodiment of the scheme, the front axle comprises a pair of wheels; and the two wheels are respectively rotatably installed on the two sides of the frame, so that the centers of the wheels are located on the sides of the frame.

[0011] In a preferred embodiment of the scheme, the hub of the wheel is rotatably installed on the rotating shaft, and an installation plate is arranged on the inner side of the rotating shaft, and the wheel is installed on the frame through the fixed installation plate.

[0012] The disconnected layout is adopted, the two wheels are respectively fixed on the two sides of the frame, and the elastic elements such as steel plate springs and shock absorbers are cancelled, so as to effectively reduce the overall height of the lifting area.

[0013] In a preferred embodiment of the scheme, the cockpit is provided with a steering system, the steering system is sequentially provided with a brake pedal and a throttle pedal from right to left, and a parking hand brake is arranged on the right side of the driving position of the steering system.

[0014] In a preferred embodiment of the scheme, the electrical accessories include a battery pack, a BMS (battery management system), a PCU (power control unit), a high-voltage box and a storage battery.

[0015] In a preferred embodiment of the scheme, the forklift chassis system further comprises a heat dissipation system, the heat dissipation system comprises a radiator and three condensers integrated in the radiator; the power system comprises a range extender, a generator, a range extender controller and a generator controller, the range extender controller is electrically connected with the range extender, and the generator controller is electrically connected with the generator; the three condensers correspondingly form three groups of circulating loops, the range extender is connected into a first group of water circulating loops, the generator, the drive motor and the PCU are connected into a second group of water circulating loops, and the battery pack is connected into a third group of water circulating loops.

[0016] In a preferred embodiment of the scheme, the radiator is arranged in the rear cabin, and the three condensers of the radiator are electrically connected with the PCU;

[0017] The thermal management system comprises temperature sensors arranged at the range extender, the battery pack, the drive motor and the radiator, and each temperature sensor is electrically connected with the PCU controller.

[0018] The forklift of the scheme separates the functions of controlling the chassis in the whole vehicle controller, integrates into the PCU, and enables the PCU to have functions of motor drive control, charge and discharge control, chassis control and the like.

[0019] The forklift chassis system adopts a controller area network (CAN) communication to connect all electrical accessories, so as to facilitate the communication between different elements. The battery is used to provide power for starting the range extender, and when the forklift is in a normal working process, the battery is charged by the range extender or the battery pack.

[0020] By replacing the engine on the traditional forklift with the range extender, the battery pack and the like system, different chassis operation modes are realized, that is, the range extender alone generates power (single range extender mode), the battery pack provides power (pure electric mode), and the range extender and the battery work simultaneously to provide power (hybrid mode), so that the endurance problem of the pure electric forklift can be solved.

[0021] In a preferred embodiment of the scheme, the high-voltage box comprises a main loop circuit, a fast charging circuit and a range extender DC / DC circuit. Through the different circuit contactors inside the high-voltage box, pure electric, hybrid, single range extender and the like working modes can be realized.

[0022] In a preferred embodiment of the scheme, the radiator comprises a frame, a fan installed on the back of the frame, and a condenser one, a condenser two and a condenser three installed in the frame.

[0023] The condenser two and the condenser three are arranged side by side in front of the fan, and the condenser one is arranged in front of the condenser two and the condenser three.

[0024] The rear end of the frame is sleeved with a wind deflector, the fan is provided with an outer frame, and the outer frame has an installation plate extending outward at the front end, the installation plate is embedded in the rear part of the wind deflector and is in butt joint with the rear end of the frame.

[0025] Three groups of condensers are arranged in the frame, and the fan is installed on the frame from the back, so that the radiator can use one fan to cool three condensers, saving the number of fans; at the same time, three-way water circulation is realized, reducing the pipeline arrangement and saving the arrangement space, and the setting of the wind deflector makes the wind blown by the fan pass through the three condensers, ensuring the heat dissipation efficiency.

[0026] In a preferred embodiment of the scheme, the lifting mechanism is composed of a gantry and a fork, the fork is liftable and installed on the gantry, and the gantry is detachably installed on the front part of the vehicle frame.

[0027] The forklift of the scheme separates the functions of controlling the chassis in the whole vehicle controller, integrates into the PCU, and enables the PCU to have functions of motor drive control, charge and discharge control, chassis control and the like.

[0028] (1) by arranging the components of the chassis system behind the driver's cabin, by controlling the layout of the chassis system, the chassis system and the lifting working area are independently placed in space, and various lifting systems can be installed and replaced; different functions are matched on the same chassis, the development cycle is shortened, and the cost is reduced; and the layout design of the forklift chassis system can balance the load of the lifting mechanism and prevent the forklift from being unbalanced;

[0029] (2) The front axle adopts a disconnected layout, two wheels are fixed on both sides of the frame, the elastic elements such as leaf springs and shock absorbers are cancelled, the chassis height is low, the vehicle height is reduced, and the environmental adaptability of the forklift is increased. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 is a schematic diagram of the overall structure of the chassis of the utility model;

[0031] Figure 2 is an installation schematic diagram of the front axle;

[0032] Figure 3 is a schematic diagram of the chassis wire harness connection of the utility model;

[0033] Figure 4 is a working mode selection principle diagram of the chassis of the utility model;

[0034] Figure 5 is a working mode process principle diagram;

[0035] Figure 6 is an explosion diagram of the radiator condenser of the utility model;

[0036] Figure 7 is a schematic diagram of the back structure of the radiator of the utility model;

[0037] Figure 8 is a schematic diagram of the water pipe interface of the radiator of the utility model;

[0038] In the drawing: 1-oil tank, 2-battery pack, 3-BMS, 4-PCU, 5-high-pressure tank, 6-battery, 7-range extender, 8-generator, 9-thermal management system, 10-rear drive axle, 11-drive motor, 12-wheel, 13-steering cylinder, 14-steering knuckle, 15-steering system, 16-accelerator pedal, 17-brake pedal, 18-front axle, 19-wire harness, 20-hydraulic oil pipe, 21-frame, 01-fan, 02-frame, 03-condenser one, 04-condenser two, 05-condenser three, 021-ventilated cover, 034-water inlet interface one, 044-water outlet interface two, 045-water inlet interface two, 054-water outlet interface three, 055-water inlet interface three. DETAILED DESCRIPTION

[0039] The technical scheme of the utility model will be described in further detail below in combination with the drawings, but the protection scope of the utility model is not limited to the following.

[0040] Reference Figure 1 A range-extending electric fork truck chassis system divides the upper part of the frame 21 into three areas: and sequentially installs the lifting mechanism 211, the driver cabin 212 and the rear engine compartment 213 in the three areas.

[0041] In this embodiment, the chassis system arranges the main components in the rear engine compartment 213 and directly fixes them on the frame 21, balances the load of the lifting mechanism through the counterweight of the rear engine compartment, prevents the fork truck from being unbalanced, and maximizes the avoidance of the lifting mechanism 211.

[0042] In this scheme, the steering system 15 is in the driver cabin 212 between the front and rear wheels, and the brake pedal and the accelerator pedal 16 are sequentially arranged to the right; the steering system 15 is provided with a parking hand brake 175 on the right side of the driver seat.

[0043] In this embodiment, the lifting mechanism 211 of the fork truck is installed in front of the steering system 15; the front axle 18 is arranged at a position more forward than the lifting mechanism 211; and Figure 2 , the front axle 18 adopts a disconnected layout, and the two wheels 12 are fixed on both sides of the frame 21, eliminating the elastic elements such as leaf springs and shock absorbers, effectively reducing the overall height of the lifting area 211.

[0044] Optionally, the installation position of the lifting mechanism 211 can also be used to install a cargo box, so as to adapt the fork truck to a low-chassis cargo truck.

[0045] In this embodiment, the rear drive axle 10 is located below the driver cabin 212, the housing of the drive motor 11 is connected with the shell support of the rear drive axle 10, the output shaft of the drive motor 11 is connected with the input shaft of the transmission, and the torque is transmitted. The drive motor can easily realize forward and reverse rotation, thereby driving the forward and reverse rotation of the wheels 12, and realizing the functions of forward and backward movement.

[0046] Reference Figure 3 Further, in this scheme, the systems and electrical elements are connected through the wire harness 19, the information of different elements is synchronized in real time in the form of CAN bus, different functions are realized by constructing CAN nodes and writing application programs that meet the requirements. For example, when charging, the PCU and other components will self-check whether there is a fault, the BMS judges whether the whole vehicle is allowed to charge, and then selects the corresponding contactor in the high-voltage box 5 to close, in each step, different electrical elements will output their own signals to ensure the safety of the system operation.

[0047] In this scheme, part of the functions in the vehicle controller is stripped and integrated into the PCU 4, so that it has the functions of motor drive control, charge and discharge control, chassis control, etc. The PCU 4 controls the operation of the drive motor, oil pump oil delivery, and collects signals such as accelerator pedal, brake, ignition, water temperature, etc. As a result, the chassis system will run independently, simplifying the functions of the forklift vehicle controller, reducing the thermal load, and only needing to design different vehicle controllers for different lifting mechanisms.

[0048] In this embodiment, the PCU is an LTPCU35X40S1607P manufactured by Chengdu LianTeng Power Control Technology Co., Ltd.

[0049] Further, in this scheme, the thermal management system 9 has three main circulating loops, and three condensers are integrated in one radiator assembly. The three condensers form three condensing loops, the first group of water circulating loops are used for the engine of the range extender 7, the second group of water circulating loops are used for the generator 8, the drive motor 11 and the PCU 4, and the third group of water circulating loops are used for the battery pack 2.

[0050] In this embodiment, two controllable three-way electromagnetic valves are contained in the first group of water circulating loops and the third group of water circulating loops, which can switch the hot water of the engine loop of the range extender 7 to the battery pack 2 loop for heating the battery pack 2 when the temperature is <-20℃ (discharge) and <0℃ (charge). After heating, the electromagnetic valve is switched to the original state, so that the two heat dissipation loops are independent.

[0051] Reference Figure 6 This embodiment further specifically integrates the radiator to save the number of fans, reduce the pipeline layout and save the layout space.

[0052] Specifically, in this embodiment, the radiator includes a frame 02, a fan 01 installed on the back of the frame 02, three condensers, a condenser one 03, a condenser two 04 and a condenser three 05; the condenser two 04 and the condenser three 05 are arranged side by side in front of the fan 01, and the condenser one 03 is arranged in front of the condenser two 04 and the condenser three 05; a wind deflector 021 is sleeved at the rear end of the frame 02, and the fan 01 is provided with an outer frame, and the outer frame of the fan 01 extends outward at the front end to form an installation plate 0101, which is embedded in the rear part of the wind deflector 021 and is connected to the rear end of the frame 02.

[0053] Further, reference Figure 6 , Figure 7The water inlet interface 034 and the water outlet interface 035 of the condenser 03 are arranged on both sides of the condenser 03, and the water circulation direction is from the water inlet interface 034 to the water outlet interface 035, so as to form a first group of water circulation loops. The water inlet and outlet interfaces of the condenser 04 and the condenser 05 are arranged on the rear side and pass through the mounting plate 0101 rearward to realize the connection with the condenser water pipeline.

[0054] With reference to Figure 8 In the embodiment, the water circulation in the condenser 04 is from the water inlet interface 045 to the water outlet interface 044, so as to form a second group of water circulation loops; and the water circulation in the condenser 05 is from the water inlet interface 055 to the water outlet interface 054, so as to form a third group of water circulation loops.

[0055] In the embodiment, the vehicle can be operated by electricity or by fuel oil, so as to improve the endurance of the forklift and improve the work efficiency.

[0056] With reference to Figure 4 The principle of selecting the working mode of the chassis in the scheme is as follows:

[0057] After the driver starts the vehicle, the ON gear (12V) is awakened, the PCU 4 starts initialization and self-checking, and sends a request for high voltage on the main loop and the boost loop to the BMS;

[0058] The BMS collects the battery capacity state and the temperature state, judges the execution working mode, for example, when the temperature < T0, only the single range extender mode is allowed to start;

[0059] The working mode signal is sent to the high-voltage box, the high-voltage box attracts the corresponding contactor, the BMS detects whether the corresponding instruction is completed within a time t, if not, the BMS sends a "fault alarm" signal to the whole vehicle, disconnects the high-voltage connection, and does not close the contactor during the power-on process, refuses to power on, and improves the safety of the system.

[0060] With reference to Figure 5 The above-mentioned high-voltage box 5 brings three different working modes to the system in the hardware design: pure electric mode, hybrid mode, and single range extender 7 mode.

[0061] As shown in a of Figure 5 In the single range extender 7 mode, the range extender 7 system works in the voltage following mode, the range extender 7 drives the generator 8 to generate electricity, the generated electricity directly powers the driving motor 11, and the vehicle is driven to move, and the battery is not charged at this time.

[0062] As shown in b of Figure 5 In the pure electric mode, the range extender 7 engine does not work, the battery pack 2 works independently, and outputs electric energy to the driving motor 11 to drive the vehicle to move.

[0063] As Figure 5 c in the mixed mode, the range extender 7 engine works to drive the generator 8 to operate, at this time the range extender system working mode is power mode, to drive the motor 11 power supply, while also charging the battery pack 2, the battery pack 2 can also be used to drive the motor 11 power supply.

[0064] It should be noted that the main working characteristics (concept) of electric vehicles is that most cases (high probability) work in pure electric mode, and a small number of cases (low probability) work in range extending mode; The electricity generated by the range extender 7 is directly supplied to the motor drive, and the excess electricity can charge the battery pack 2 (in simple terms, the range extender electric forklift and the range extender electric vehicle on the market have the same principle, which are prior art, and will not be described here). In addition, the BMS management system controls the charging and discharging action of the battery pack, and the PCU sends instructions to switch the working mode, which are all prior art and will not be described here.

[0065] Further preferably, in the embodiment, the lifting mechanism is composed of a gantry and a fork, the fork is installed on the gantry in a lifting manner (the gantry and the fork are common mechanical structures in the prior art, and will not be expanded in detail in the present scheme), and the gantry is detachably installed on the front part of the vehicle frame. Since the chassis system and the lifting working area are independently placed in space in the present embodiment, the fork or the gantry can be replaced or disassembled, so that different lifting systems can be replaced, and different functions can be matched on the same chassis.

[0066] The above is only the preferred embodiment of the present application, and it should be understood that the present application is not limited to the form disclosed herein, and should not be considered as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the concept described herein by the above teachings or related art or knowledge. The modification and change made by the person skilled in the art without departing from the spirit and scope of the present application shall be within the protection scope of the claims attached to the present application.

Claims

1. An extended-range electric forklift chassis system, characterized by: including a frame (21); The vehicle frame (21) is provided with a lifting mechanism (211), a cockpit (212), and a rear cabin (213) in sequence from front to back; The rear cabin (213) is provided with a fuel tank (1), electrical accessories, a power system, and a thermal management system; A front axle (18) and a rear drive axle (10) are provided below the vehicle frame (21), wherein the rear drive axle (10) is provided below the driving cabin (212), and the front axle (18) is provided at the front bottom end of the lifting mechanism (211).

2. The extended-range electric forklift chassis system according to claim 1, characterized in that: The front axle (18) includes a pair of wheels (12); The two wheels (12) are rotatably mounted on both sides of the vehicle frame (21) so that the centers of the wheels (12) are located beside the vehicle frame (21).

3. The extended-range electric forklift chassis system according to claim 2, characterized in that: The wheel hub of the wheel (12) is rotatably mounted on the rotating shaft, and a mounting plate is provided at the inner end of the rotating shaft. The wheel (12) is mounted on the vehicle frame (21) via the fixed mounting plate.

4. The extended-range electric forklift chassis system according to claim 3, characterized in that: The cockpit (212) is provided with a steering system (15), and the steering system (15) is provided with a brake pedal (1741) and an accelerator pedal (16) in sequence to the right. The steering system (15) is provided with a parking brake (175) on the right side of the driver's seat.

5. The extended-range electric forklift chassis system according to claim 4, characterized in that: The electrical accessories include a battery pack (2), a BMS (3), a PCU (4), a high-voltage box (5), and a battery (6).

6. The extended-range electric forklift chassis system according to claim 5, characterized in that: The forklift chassis system further includes a heat dissipation system, which includes a radiator and three condensers integrated in the radiator; The power system includes a range extender (7), a generator (8), a range extender controller, and a generator controller, wherein the range extender controller is electrically connected to the range extender (7), and the generator controller is electrically connected to the generator (8); The three condensers form three sets of circulation loops. The range extender (7) is connected to the first set of water circulation loops, the generator (8), the drive motor (11), and the PCU (4) are connected to the second set of water circulation loops, and the battery pack (2) is connected to the third set of water circulation loops.

7. The extended-range electric forklift chassis system according to claim 6, characterized in that: The radiator is arranged in the rear engine compartment (213), and the three condensers of the radiator are electrically connected to the PCU (4) respectively; The thermal management system includes temperature sensors arranged at various locations of the range extender (7), the battery pack (2), the drive motor (11), and the radiator, and each temperature sensor is electrically connected to the PCU controller.

8. The extended-range electric forklift chassis system according to claim 6, characterized in that: The radiator comprises a frame (02), a fan (01) installed on the back of the frame (02), and a condenser 1 (03), a condenser 2 (04), and a condenser 3 (05) installed in the frame (02); The condenser 2 (04) and the condenser 3 (05) are arranged side by side in front of the fan (01), and the condenser 1 (03) is arranged in front of the condenser 2 (04) and the condenser 3 (05); The rear end of the frame (02) is provided with an air guide cover (021), the fan (01) is provided with an outer frame, and a mounting plate (0101) extends outward from the front end of the outer frame, and the mounting plate (0101) is embedded in the rear part of the air guide cover (021) and forms a butt joint with the rear end of the frame (02).

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