Electric forklift energy management control system

Abstract

The utility model relates to an energy management control system of an electric fork-lift truck, the electric fork-lift truck comprises an oil tank and a multi-way valve, and the energy management control system of the electric fork-lift truck is characterized in that a switching piece for changing internal circulation or external circulation is arranged between an internal air inlet and an external air inlet of an internal and external circulation air duct; the radiator is arranged in the internal and external circulation air duct, an oil outlet of a fluid channel of the radiator is communicated with an oil return pipe of the oil tank, and an oil inlet of the radiator is communicated with an oil return port of the multi-way valve; and the detection piece is used for detecting the temperature of a cab of the electric forklift and the temperature of the hydraulic oil in the oil tank. The radiator and the internal and external circulation channel are arranged, internal circulation or external circulation is switched to be started through the switching piece according to the temperature of the cab of the electric forklift and the temperature of hydraulic oil in the oil tank, and heat of the hydraulic oil can be used for heating the cab or blowing the heat of the hydraulic oil out of the forklift. The temperature of hydraulic oil can be greatly reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of forklift energy management, in particular to an energy management control system for an electric forklift. Background Art

[0002] Due to the space limitations of electric forklifts and the particularity of their energy supply, the kinetic energy of electric forklifts comes from the battery supply. Therefore, most of the heating systems inside the cab use PTC heating, and then use fan circulation to heat. Because the battery power on the forklift is limited and the power of the electric heater is limited, when working outdoors in cold weather, coupled with the general sealing of the forklift's cab, the temperature inside the cab rises very slowly, resulting in a poor user experience.

[0003] At present, the gantry-related working devices on electric forklifts mainly transfer energy through hydraulic oil. The hydraulic oil needs to participate in the work when the gantry moves and turns. While transferring kinetic energy, the hydraulic oil will produce energy loss and cause the temperature of the hydraulic oil to rise. This part of the oil temperature is generally dissipated through the oil tank, but the heat dissipation of the oil tank is affected by factors such as the volume of the oil tank and the external ambient temperature. Therefore, when the ambient temperature is high, the continuous high temperature hydraulic oil will cause the efficiency of the transmission system to be greatly reduced. High temperature hydraulic oil will cause the life of related components such as motors, multi-way valves, oil pipes, and sealing rings to be greatly reduced. Utility Model Content

[0004] Based on this, in response to the current technical problems, the purpose of the utility model is to provide an energy management and control system for an electric forklift, which can use the heat of the hydraulic oil to heat the cab in cold weather, and can quickly increase the temperature of the cab, making the cab occupants more comfortable in winter or in low temperature areas. It can also greatly reduce the temperature of the hydraulic oil, keep the hydraulic oil temperature relatively stable, and allow the hydraulic oil in the gantry working device to work at a relatively low temperature all year round, which can greatly increase the life of the hydraulic transmission system and its components.

[0005] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0006] The utility model provides an energy management and control system for an electric forklift, the electric forklift comprising a battery module, a fuel tank and a multi-way valve, the energy management and control system for the electric forklift comprising:

[0007] An internal and external circulation air duct is provided with an internal air inlet opening toward the cab of the electric forklift for internal circulation and an external air inlet opening toward the outside for external circulation, and a switching member for changing internal circulation or external circulation is provided between the internal air inlet and the external air inlet;

[0008] A radiator, which is arranged in the internal and external circulation air duct, the oil outlet of the fluid channel of which is connected to the oil return pipe of the oil tank and the oil inlet of which is connected to the oil return port of the multi-way valve; and

[0009] The detection component is used to detect the temperature of the cab of the electric forklift and the temperature of the hydraulic oil in the oil tank.

[0010] The electric forklift energy management and control system provided by the utility model is provided with a radiator and internal and external circulation channels, and switches to open the internal circulation or the external circulation through a switching member according to the cab temperature of the electric forklift and the temperature of the hydraulic oil in the oil tank; in cold weather, when the cab temperature is low, the internal circulation is switched on through the switching member, and the hydraulic oil is introduced into the radiator. When the hydraulic oil temperature reaches a predetermined value, the radiator is started and the heat of the hydraulic oil is blown to the cab, which can assist the heater to heat the cab at the same time, and can quickly increase the temperature of the cab, making the cab occupants in winter or in low temperature areas more comfortable; when used in a high temperature environment, the cab temperature is high, and the external circulation is switched on through the switching member. When the hydraulic oil temperature reaches a predetermined value, the radiator is started and the heat of the hydraulic oil is blown out of the vehicle, which can greatly reduce the temperature of the hydraulic oil, keep the hydraulic oil temperature relatively stable, and allow the hydraulic oil in the gantry working device to work at a relatively low temperature all year round, which can greatly increase the life of the hydraulic transmission system and its components.

[0011] As a further improvement of the above-mentioned scheme of the utility model, the electric forklift also includes a battery module, and the electric forklift energy management control system also includes an energy management controller. A main contactor control circuit and a switch control circuit are arranged between the energy management controller and the battery module. The energy management controller is connected to the switching element, the radiator, the electromagnetic reversing valve and the detection element.

[0012] As a further improvement of the above scheme of the utility model, the main contactor control circuit includes a main contactor, the positive terminal of the battery module is connected to one end of the main contactor contact through a discharge relay, the other end of the main contactor contact is connected to the positive terminal of the energy management controller, the two ends of the main contactor coil are respectively connected to the 2A11 and 2A12 ports of the energy management controller, and the negative terminal of the energy management controller is connected to the negative terminal of the battery module;

[0013] The switch control circuit includes an emergency stop switch and a key switch. The positive end of the battery module is connected to one end of the emergency stop switch, the other end of the emergency stop switch is connected to one end of the key switch, and the other end of the key switch is connected to the key end of the energy management controller.

[0014] As a further improvement of the above scheme of the utility model, the electric forklift also includes a heater, and a DC-DC converter power circuit is arranged between the heater, the battery module and the energy management controller; the DC-DC converter power circuit includes a DC-DC converter, a delay relay and a heater switch, the positive end of the battery module is respectively connected to the positive input end of the DC-DC converter and one end of the delay relay contact through a discharge relay, the positive output end of the DC-DC converter is connected to one end of the heater switch and its C end is connected to the other end of the key switch, the other end of the heater switch is connected to one end of the delay relay coil, the other end of the delay relay coil is connected to the 2A3 port of the energy management controller, the other end of the delay relay contact is connected to the fan motor and PTC heater of the heater, and the fan motor and PTC heater of the heater are both connected to the negative end of the battery module.

[0015] As a further improvement of the above-mentioned scheme of the utility model, the electric forklift energy management and control system also includes an interlocking relay; the PTC heater of the heater has gear one and gear two, and the working power of gear one is greater than the working power of gear two, the two ends of the interlocking relay coil are respectively connected to the 2A2 port of the energy management controller and the negative end of the battery module, one end of the normally closed contact and the normally open contact of the interlocking relay are both connected to the other end of the delay relay contact, and the other ends of the normally closed contact and the normally open contact of the interlocking relay are respectively connected to gear one and gear two of the PTC heater.

[0016] As a further improvement of the above-mentioned scheme of the utility model, the electric forklift energy management and control system also includes a heater forced switch; one end of the heater forced switch is connected to the 2A4 port of the energy management controller and grounded, and the other end is connected to the other end of the delay relay coil.

[0017] As a further improvement of the above scheme of the utility model, the detection element includes temperature sensor 1 and temperature sensor 2, wherein temperature sensor 1 is used to detect the temperature of the cab of the electric forklift and is connected to the energy management controller, and temperature sensor 2 is used to detect the temperature of the hydraulic oil in the oil tank and is connected to the energy management controller.

[0018] As a further improvement of the above-mentioned scheme of the utility model, the switching component includes a guide flap, a flip motor and a relay 1; the guide flap is installed on the output shaft of the flip motor, and in the default state, the guide flap covers the inner air inlet for external circulation; the two ends of the coil of the relay 1 are respectively connected to the 2A10 port of the energy management controller and the negative end of the battery module, and the two ends of the contact of the relay 1 are respectively connected to the positive output end of the DC-DC converter and the positive end of the flip motor, and the negative end of the flip motor is connected to the negative end of the battery module.

[0019] As a further improvement of the above-mentioned scheme of the utility model, the electric forklift energy management control system also includes relay 2, the two ends of the coil of relay 2 are respectively connected to the 2A5 port of the energy management controller and the negative end of the battery module, the two ends of the contact of relay 2 are respectively connected to the positive output end of the DC-DC converter and the positive end of the fan motor of the radiator, and the negative end of the fan motor of the radiator is connected to the negative end of the battery module.

[0020] As a further improvement of the above scheme of the utility model, the electric forklift energy management and control system also includes a three-way valve, the three-way valve having an inlet and outlet one and outlet two connected to the inlet, the inlet is connected to the oil return port of the multi-way valve and the outlet one and outlet two are respectively connected to the oil inlet of the fluid channel of the radiator and the oil return pipe of the oil tank, and an electromagnetic reversing valve for controlling the on-off between the inlet and outlet one and outlet two is arranged in the three-way valve, and the two ends of the electromagnetic reversing valve coil are respectively connected to the 2A5 port of the energy management controller and the negative end of the battery module.

[0021] Compared with the prior art, the utility model has the following beneficial effects:

[0022] 1. The energy management and control system of an electric forklift provided by the utility model is provided with a radiator and internal and external circulation channels, and switches on the internal circulation or the external circulation through a switching member according to the temperature of the cab of the electric forklift and the temperature of the hydraulic oil in the tank; in cold weather, when the temperature of the cab is low, the internal circulation is switched on through the switching member, and the hydraulic oil is introduced into the radiator. When the temperature of the hydraulic oil reaches a predetermined value, the radiator is started and the heat of the hydraulic oil is blown to the cab, which can assist the heater to heat the cab at the same time, and can quickly increase the temperature of the cab, making the cab occupants more comfortable in winter or in low temperature areas; when used in a high temperature environment, the temperature of the cab is high, and the external circulation is switched on through the switching member. When the temperature of the hydraulic oil reaches a predetermined value, the radiator is started and the heat of the hydraulic oil is blown out of the vehicle, which can greatly reduce the temperature of the hydraulic oil, keep the hydraulic oil temperature relatively stable, and allow the hydraulic oil in the gantry working device to work at a relatively low temperature all year round, which can greatly increase the life of the hydraulic transmission system and its components.

[0023] 2. The energy management and control system of the electric forklift provided by the utility model uses the heat of the hydraulic oil to heat the cab while the heater is providing heating. When the temperature of the hydraulic oil reaches a certain threshold, the energy management system can automatically reduce the heating power of the heater of the heater of the heater of the heater and use the heat of the hydraulic oil for auxiliary heating of the cab, which can increase the heating power of the cab and allow the cab to heat up quickly, thereby reducing the energy consumption of the entire vehicle and extending the service life of the battery of the entire vehicle. When the temperature of the hydraulic oil continues to rise, the energy management system automatically disconnects the heater and uses the heat of the hydraulic oil for pure heating of the cab, which can extend the service life of the electric forklift and quickly reduce the temperature of the hydraulic oil. The heat management system can keep the temperature of the hydraulic oil relatively stable and allow the hydraulic oil in the gantry working device to work at a relatively low temperature all year round, which can greatly increase the life of the hydraulic transmission system and its components.

[0024] 3. When the utility model is used in a low-temperature environment, in order to prevent low-temperature hydraulic oil from entering the radiator, a three-way valve is arranged between the oil return port of the multi-way valve and the radiator, wherein the switching of the three-way valve is controlled by the electromagnetic reversing valve. When the electromagnetic reversing valve is not energized, the hydraulic oil directly returns to the oil tank from the oil return port. When the electromagnetic reversing valve is energized and connected, the three-way valve starts to work, and the hydraulic oil enters the radiator from the oil return port and then returns to the oil tank, thereby preventing low-temperature hydraulic oil from entering the radiator.

[0025] 4. When the utility model utilizes the heat of the hydraulic oil to purely heat the cab, if the cab temperature is still low, the driver can force the heater switch to close. At this time, the delay relay coil is powered on again, the delay relay contacts are closed again, and the heater re-participates in the cab heating, thereby greatly improving the cab comfort for users in extremely cold areas. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A circuit schematic diagram of an electric forklift energy management control system proposed in an embodiment of the utility model;

[0027] Figure 2 This is a schematic structural diagram of an internal and external circulation air duct in an electric forklift energy management and control system proposed in an embodiment of the utility model.

[0028] Figure markings: 1. internal and external circulation air duct; 2. internal air inlet; 3. external air inlet; 4. energy management controller; 5. heater; 6. heater switch; 7-1. coil of time delay relay; 7-2. contact of time delay relay; 8. interlock relay; 9. heater forced switch; 10. temperature sensor 1; 11. temperature sensor 2; 12. flip motor; 13. guide flap; 14-1. coil of relay 1; 14-2. contact of relay 1; 15. relay 2; 16. fan motor of radiator; 17. battery module; 18. discharge relay; 19-1. coil of main contactor; 19-2. contact of main contactor; 20. emergency stop switch; 21. key switch; 22. DC-DC converter; 23. coil of electromagnetic reversing valve. DETAILED DESCRIPTION

[0029] In order to facilitate the understanding of the present invention, the present invention will be described more comprehensively in conjunction with specific embodiments below. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thoroughly and comprehensively understood.

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0031] This embodiment provides an electric forklift energy management control system for energy management of the electric forklift, the electric forklift includes a battery module 17, a fuel tank, a multi-way valve and a heater 5. Figure 1 The electric forklift energy management control system of this embodiment includes an internal and external circulation air duct 1, a radiator, a three-way valve, a detection component and an energy management controller 4, and may also include a delay relay, an interlock relay 8, a heater forced switch 9 and a relay 2 15.

[0032] A main contactor control circuit and a switch control circuit are provided between the energy management controller 4 and the battery module 17. The main contactor control circuit includes a main contactor MC, the positive terminal of the battery module 17 is connected to one end of the contact 19-2 of the main contactor through the discharge relay 18, the other end of the contact 19-2 of the main contactor is connected to the positive terminal of the energy management controller 4, the two ends of the coil 19-1 of the main contactor are respectively connected to the 2A11 and 2A12 ports of the energy management controller 4, and the negative terminal of the energy management controller 4 is connected to the negative terminal of the battery module 17. The switch control circuit includes an emergency stop switch 20 and a key switch 21, the positive terminal of the battery module 17 is connected to one end of the emergency stop switch 20, the other end of the emergency stop switch 20 is connected to one end of the key switch 21, and the other end of the key switch 21 is connected to the key terminal of the energy management controller 4. When the key switch 21 is closed and the electric forklift is powered on, the energy management controller 4 completes the self-check, drives the coil 19-1 of the main contactor MC, closes the contact 19-2 of the main contactor MC, and the energy management controller 4 completes the power-on process.

[0033] The detection component is used to detect the temperature T2 of the hydraulic oil in the oil tank and the temperature T1 of the cab of the electric forklift. In this embodiment, the detection component includes a temperature sensor 19 and a temperature sensor 210. The temperature sensor 19 is used to detect the temperature T1 of the cab of the electric forklift in real time, and the temperature sensor 210 is used to detect the temperature T2 of the hydraulic oil in the oil tank in real time. The temperature sensor 19 and the temperature sensor 210 are both connected to the energy management controller 4. After the energy management controller 4 completes the power-on process, the temperature sensor 19 and the temperature sensor 210 are powered on and respectively detect the temperature T1 of the cab of the electric forklift and the temperature T2 of the hydraulic oil in the oil tank in real time. The energy management controller 4 can obtain the temperature T1 of the cab of the electric forklift and the temperature T2 of the hydraulic oil in the oil tank in real time. The temperature T1 of the cab of the electric forklift and the temperature T2 of the hydraulic oil in the oil tank can be displayed in real time on the display of the electric forklift, which is convenient for the driver to view. By prior setting, when the temperature T1 of the cab of the electric forklift is lower than the preset temperature value -T 01 (In this embodiment, T 01 =15°C), the 2A10 port of the energy management controller 4 outputs a high level; when the temperature T2 of the hydraulic oil in the oil tank is lower than the preset temperature value T2, 02 (In this embodiment, T 02 =40°C), the 2A3 port of the energy management controller 4 outputs a low level; when the temperature T2 of the hydraulic oil in the oil tank reaches the preset temperature value T2, 02 (In this embodiment, T 02 =40°C), the 2A2 port of the energy management controller 4 outputs a low level, and the 2A5 port of the energy management controller 4 outputs a high level; when the temperature T2 of the hydraulic oil in the oil tank reaches the preset temperature value T 03(In this embodiment, T 03 =60°C), the 2A3 port of the energy management controller 4 outputs a high level. Of course, in the embodiment, as long as T 01 、T 02 、T 03 As time goes by, T 01 、T 02 、T 03 Other temperature values ​​can also be set individually.

[0034] The heater 5 is a common heating tool for electric forklifts. In this embodiment, the heater 5 adopts the existing technology. The heater 5 mainly includes a PTC heater and a fan. The PTC heater of the heater 5 has a gear position 1 and a gear position 2. When the PTC heater of the heater 5 is in gear position 1, the PTC heater of the heater 5 is PTC. max (In this embodiment, P max = 1000W) work; when the PTC heater of the heater 5 is in gear two, the PTC heater of the heater 5 is xP max Work, in this embodiment, x=0.5, of course, in other embodiments, x can also take other values ​​between 0-1. A DC-DC converter power circuit is provided between the heater 5, the battery module 17, and the energy management controller 4. The DC-DC converter power circuit includes a DC-DC converter 22 and a heater switch 6. The positive terminal of the battery module 17 is connected to the positive input terminal of the DC-DC converter 22 and one end of the contact 7-2 of the delay relay through the discharge relay 18. The positive output terminal of the DC-DC converter 22 is connected to one end of the heater switch 6 and its C end is connected to the other end of the key switch 21. The other end of the heater switch 6 is connected to one end of the coil of the delay relay, and the other end of the coil 7-1 of the delay relay is connected to the 2A3 port of the energy management controller 4. The other end of the contact 7-2 of the delay relay is connected to the fan motor of the heater 5. One end of the normally closed contact of the interlock relay 8 and one end of the normally open contact of the interlock relay 8 are connected to the other end of the contact 7-2 of the time delay relay, and the other end of the normally closed contact of the interlock relay 8 and the other end of the normally open contact of the interlock relay 8 are respectively connected to the gear 1 and gear 2 of the PTC heater of the heater 5, and the fan motor and PTC heater of the heater 5 are both connected to the negative end of the battery module 17, and the two ends of the coil of the interlock relay 8 are respectively connected to the 2A2 port of the energy management controller 4 and the negative end of the battery module 17. One end of the heater forced switch 9 is connected to the 2A4 port of the energy management controller 4 and grounded, and the other end is connected to the other end of the coil 7-1 of the time delay relay.

[0035] Through the above structural setting, the working principle of the heater 5 is: when the hydraulic oil temperature T2 is lower than 40°C, the driver manually closes the heater switch 6, the 2A3 port of the energy management controller 4 outputs a low level, the coil of the delay relay works, the contacts of the delay relay are closed, the PTC heater and the fan motor of the heater 5 work, and the PTC heater works normally in gear one; when the temperature T2 of the hydraulic oil in the tank reaches 40°C, the 2A2 port of the energy management controller 4 outputs a low level, the coil of the interlock relay 8 works, and the normally open contacts of the interlock relay 8 close. And its normally closed contacts are disconnected, the PTC heater automatically reduces the heating power, the PTC heater switches from gear one to gear two, and its power is reduced from 1000W to 500W; when the temperature T2 of the hydraulic oil in the tank reaches 60°C, the 2A3 port of the energy management controller 4 outputs a high level, automatically disconnects the delay relay coil, thereby disconnecting the delay relay contacts, and shuts off the heater 5. At this time, if the heater forced switch 9 is forced to close, the coil of the delay relay is powered on again, the contacts of the delay relay are closed again, and the heater 5 resumes heating the cab.

[0036] It should be noted that there are pre-charging resistors at both ends of the discharge contactor of the battery module 17 of the electric forklift. During the power-on process, the lithium battery first pre-charges the pre-charging resistors, and the power-on can be completed only after the pre-charging is completed. During the pre-charging process, when the large-load heater 5 is directly connected to both ends of the battery module 17 for power-on, the pre-charging time will be extended, resulting in the energy management controller 4 being unable to detect the rated voltage of the battery within the preset time range, resulting in the failure of the vehicle to power on. In order to avoid starting with a large load during the vehicle power-on process, a delay relay is added in this embodiment, and the delay time of the delay relay is set to 4s. The principle of the delay relay is: if the heater switch 6 is closed in advance, and then the key switch 21 is closed, the energy management controller 4 completes the self-check at this time, drives the coil of the main contactor, and the contacts of the main contactor are closed. The energy management controller 4 completes the power-on process. It takes 4s to wait for the heater 5 to complete the power-on, but within 4s, the battery module 17 and the energy management controller 4 have already completed the power-on, so there will be no load start failure.

[0037] Reference Figure 2, the internal and external circulation air duct 1 is provided with an internal air inlet 2 opened to the cab of the electric forklift for internal circulation and an external air inlet 3 opened to the outside for external circulation, and a switching member for changing the internal circulation or the external circulation is provided between the internal air inlet 2 and the external air inlet 3. In this embodiment, the switching member includes a guide flap 13, a flip motor 12 and a relay 1. The guide flap 13 is mounted on the output shaft of the flip motor 12. The two ends of the coil 14-1 of the relay 1 are respectively connected to the 2A10 port of the energy management controller 4 and the negative end of the battery module 17, the two ends of the contact 14-2 of the relay 1 are respectively connected to the positive output end of the DC-DC converter 22 and the positive end of the flip motor 12, the negative end of the flip motor 12 is connected to the negative end of the battery module 17, and in the default state, the contact 14-2 of the relay 1 is disconnected, the guide flap 13 covers the internal air inlet 2, and the external air inlet 3 is opened for external circulation. Relay 1 receives a signal from the energy management controller 4, and decides whether to trigger according to the signal level (high or low). In this embodiment, relay 1 uses a high-level triggered relay. When the cab temperature T1 of the electric forklift is lower than 15°C, the 2A10 port of the energy management controller 4 outputs a high level, the coil 14-1 of relay 1 works, the contact 14-2 of relay 1 is closed, and the flip motor 12 starts to drive the guide flap 13 to flip and cover the outer air inlet 3. At this time, the inner air inlet 2 is opened for internal circulation. Taking into account the surge voltage that may be generated when the flip motor 12 starts and stops, the relay 1 of this embodiment can choose a relay model with surge interference resistance. The internal and external circulation air ducts 1 of this embodiment can be set with reference to the internal and external circulation air ducts of the existing reference car, which will not be elaborated here.

[0038] The radiator is arranged in the internal and external circulation air duct. In this embodiment, the radiator adopts an air-cooled radiator known in the prior art, and the oil outlet of the fluid channel of the radiator is connected to the oil return pipe of the oil tank of the electric forklift. The two ends of the coil of the relay 2 15 are respectively connected to the 2A5 port of the energy management controller 4 and the negative end of the battery module 17, and the two ends of its contact are respectively connected to the positive output end of the DC-DC converter 22 and the positive end of the fan motor 16 of the radiator, and the negative end of the fan motor 16 of the radiator is connected to the negative end of the battery module 17. Relay 2 15 receives a signal from the energy management controller 4 and determines whether to trigger according to the level of the signal (high or low). In this embodiment, relay 2 15 adopts a high-level triggered relay. When the temperature T2 of the hydraulic oil in the oil tank reaches 40°C, the 2A5 port of the energy management controller 4 outputs a high level, the coil of relay 2 15 works, the contacts of relay 2 15 are closed, and the fan motor 16 of the radiator is powered on and starts to drive the fan of the radiator to rotate.

[0039] The three-way valve has an inlet and outlets 1 and 2 connected to the inlet. The inlet is connected to the oil return port of the multi-way valve, and outlets 1 and 2 are respectively connected to the oil inlet of the fluid channel of the radiator and the oil return pipe of the oil tank of the electric forklift. The three-way valve is provided with an electromagnetic reversing valve for controlling the channel between the inlet and outlets 1 and 2. The two ends of the coil of the electromagnetic reversing valve are respectively connected to the 2A5 port of the energy management controller 4 and the negative end of the battery module 17. The electromagnetic reversing valve determines whether to change direction according to the signal of the energy management controller 4. When the temperature T2 of the hydraulic oil in the oil tank reaches 40°C, the 2A5 port of the energy management controller 4 outputs a high level, the coil 23 of the electromagnetic reversing valve is energized, the inlet of the three-way valve is connected to the outlet 1, and the hydraulic oil at the oil return port of the multi-way valve flows into the fluid channel of the radiator and then flows back to the oil tank through the oil return pipe; when the energy management controller 4 stops outputting a high level, the coil 23 of the electromagnetic reversing valve loses power, the inlet of the three-way valve is connected to the outlet 2, and the hydraulic oil at the oil return port of the multi-way valve flows directly back to the oil tank from the oil return pipe. By setting a three-way valve and an electromagnetic reversing valve, when used in a low-temperature environment, in order to prevent low-temperature hydraulic oil from entering the radiator, a three-way valve is added between the oil return port of the multi-way valve and the radiator, and the switching of the three-way valve is controlled by the electromagnetic reversing valve. When the electromagnetic reversing valve is not energized, the hydraulic oil returns directly to the oil tank from the oil return port of the multi-way valve; when the electromagnetic reversing valve is energized and connected, the three-way valve starts to work, and the hydraulic oil enters the liquid channel of the radiator from the oil return port and then returns to the oil tank.

[0040] Through the above structure setting, the energy management controller 4 controls the driving electromagnetic reversing valve, relay 2 15, interlock relay 8, delay relay and relay 1 according to the temperature T1 of the hydraulic oil in the oil tank and the cab temperature T2 of the electric forklift, thereby controlling the radiator, heater 5, and switching element to perform energy management on the electric forklift. The specific management method includes:

[0041] 1. When used in cold environment

[0042] The key switch 21 is closed, the electric forklift is powered on, the energy management controller 4 completes the self-check, drives the coil 19-1 of the main contactor MC, the contact 19-2 of the main contactor MC is closed, and the energy management controller 4 completes the power-on process; the temperature sensor 1 9 and the temperature sensor 2 10 are powered and respectively detect the cab temperature T1 of the electric forklift and the temperature T2 of the hydraulic oil in the tank in real time;

[0043] The energy management controller 4 pre-sets a preset temperature value T 01 , preset temperature value 2T 02 And the preset temperature value three T 03 , T 01 、T 02 、T 03 Increase successively. In this method, T 01 、T02 , T 03 are set to 15°C, 40°C, and 60°C respectively (it should be noted that in other embodiments, as long as the energy management requirements are met, T 01 , T 02 , T 03 The energy management controller 4 obtains the cab temperature T1 of the electric forklift according to the temperature sensor 9 and compares T1 with the preset temperature value T 01 =15℃ to control the switch between internal and external circulation, and compare the temperature T2 of the hydraulic oil in the oil tank with T 02 , T 03 Compare;

[0044] In a cold environment, when the electric forklift starts to start, the cab temperature T1 is less than 15°C. At this time, the 2A10 port of the energy management controller 4 outputs a high level to make the coil 14-1 of the relay 1 work, and the contact 14-2 of the relay 1 is closed. The flip motor 12 starts to drive the guide flap 13 to flip to a predetermined angle to cover the outer air inlet. At this time, the inner air inlet is opened for internal circulation;

[0045] When the electric forklift starts, the hydraulic oil temperature in the tank is low, that is, T2 <T 02 =40℃, at this time, if the electric forklift driver manually closes the heater switch 6, the 2A3 port of the energy management controller 4 outputs a low level, the coil of the delay relay works, the contact of the delay relay is closed, the normally closed contact of the interlock relay 8 is closed, and the PTC heater of the heater 5 is in the gear position and P max (In this embodiment, P max = 1000W) works normally and the fan of the heater 5 rotates to heat the cab; however, the heating power of the heater 5 is limited, resulting in that when working outdoors in cold weather and the cab of the forklift is generally sealed, the temperature inside the cab rises very slowly;

[0046] As the forklift is used, the temperature T1 of the hydraulic oil in the oil tank will increase. When 40℃≤T2<60℃, the 2A5 port of the energy management controller 4 drives the coil of the electromagnetic reversing valve and the coil of the relay 2 15. The electromagnetic reversing valve introduces the hydraulic oil from the return oil port into the liquid flow of the radiator for heat circulation. At the same time, the contact of the relay 2 15 is closed, and the fan motor 16 of the radiator starts to drive the fan of the radiator to rotate, blowing the heat of the hydraulic oil into the cab. The heat of the hydraulic oil is used for auxiliary heating of the cab, which can increase the heating rate of the cab and allow the cab to heat up quickly. At the same time, the 2A2 port of the energy management controller 4 drives the coil of the interlock relay 8, the normally closed contact of the interlock relay 8 is disconnected, and the normally open contact of the interlock relay 8 is closed, automatically reducing the heating power of the PTC heater. The PTC heater switches from gear one to gear two, and its power is reduced from 1000W of the original gear one to 500W of gear two.

[0047] When the temperature of the hydraulic oil in the tank is T2 ≥ T 03 =60℃, the 2A3 port of the energy management controller 4 outputs a 12V high level to automatically disconnect the coil of the delay relay, thereby disconnecting the contact of the delay relay and stopping the heater 5 from working. At this time, the heat of the hydraulic oil temperature is used to heat the cab purely, which can extend the service life of the electric forklift, and can quickly reduce the hydraulic oil temperature and improve the efficiency of the hydraulic transmission system. The heat management system can keep the hydraulic oil temperature relatively stable, so that the hydraulic oil in the gantry working device can work at a relatively comfortable temperature all year round, which can greatly improve the life of the hydraulic transmission system and its components;

[0048] In the case of pure cab heating by the heat of the hydraulic oil temperature, if the driver still feels cold, the driver can manually force the heater forced switch 9 to close, at which time the coil of the delay relay is powered on again, the contacts of the delay relay are closed again, the heater 5 is re-engaged and the PTC heater of the heater 5 is in the second gear and works at 500W to heat the cab, so that the cab comfort of users in extremely cold areas is greatly improved;

[0049] As the cab is heated, if T1 ≥ 15°C, the 2A10 port of the energy management controller 4 stops outputting a low level, the contact 14-2 of the relay 1 is disconnected, and the flip motor drives the guide flap to flip to a predetermined angle and reset to cover the inner air inlet. At this time, the outer air inlet is opened for external circulation, blowing the heat of the hydraulic oil out of the cab, thereby reducing the temperature of the hydraulic oil and improving the efficiency of the hydraulic transmission system.

[0050] 2. When used in high temperature environment

[0051] The key switch 21 is closed, the electric forklift is powered on, the energy management controller 4 completes the self-check, drives the coil of the main contactor MC, the contacts of the main contactor MC are closed, and the energy management controller 4 completes the power-on process; the temperature sensor 1 9 and the temperature sensor 2 10 are powered and respectively detect the cab temperature T1 of the electric forklift and the temperature T2 of the hydraulic oil in the tank in real time;

[0052] The energy management controller 4 pre-sets a preset temperature value T 01 , preset temperature value 2T 02 And the preset temperature value three T 03 , similarly, T 01 、T 02 、T 03 The energy management controller 4 obtains the cab temperature T1 of the electric forklift according to the temperature sensor 9 and compares T1 with the preset temperature value T1. 01 =15℃ to control the switch between internal and external circulation, and compare the temperature T2 of the hydraulic oil in the oil tank with T 02 、T 03 Compare;

[0053] In a high temperature environment, the cab temperature T1 ≥ 15°C, at which time the guide flap is in the default state to cover the inner air inlet, and at this time, the outer air inlet is opened for external circulation;

[0054] When the electric forklift starts, the temperature of the hydraulic oil in the tank is low. As the forklift is used, the temperature T1 of the hydraulic oil in the tank will increase. When 40℃≤T2<60℃, the 2A5 port of the energy management controller 4 drives the electromagnetic reversing valve and relay 2 15. The electromagnetic reversing valve introduces the hydraulic oil from the return oil port into the liquid flow of the radiator for heat circulation. At the same time, the fan motor 16 of the radiator starts to drive the radiator fan to rotate, blowing the heat of the hydraulic oil out of the cab to dissipate the heat of the hydraulic oil, thereby reducing the temperature of the hydraulic oil. The hydraulic oil temperature can be quickly reduced and the efficiency of the hydraulic transmission system can be improved. The heat management system can keep the hydraulic oil temperature relatively stable and allow the hydraulic oil in the gantry working device to work at a relatively comfortable temperature all year round, which can greatly improve the life of the hydraulic transmission system and its components.

[0055] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0056] The above-mentioned embodiments only express several implementation methods of the utility model, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the utility model patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, which all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model patent shall be based on the attached claims.

Claims

1. An energy management control system for an electric forklift, the electric forklift comprising a fuel tank and a multi-way valve, characterized in that: The electric forklift energy management control system comprises: An internal and external circulation air duct is provided with an internal air inlet opening toward the cab of the electric forklift for internal circulation and an external air inlet opening toward the outside for external circulation, and a switching member for changing internal circulation or external circulation is provided between the internal air inlet and the external air inlet; A radiator, which is arranged in the internal and external circulation air duct, the oil outlet of the fluid channel of which is connected to the oil return pipe of the oil tank and the oil inlet of which is connected to the oil return port of the multi-way valve; and The detection component is used to detect the temperature of the cab of the electric forklift and the temperature of the hydraulic oil in the oil tank.

2. The electric forklift energy management control system according to claim 1, characterized in that: The electric forklift also includes a battery module, and the electric forklift energy management control system also includes an energy management controller. A main contactor control circuit and a switch control circuit are arranged between the energy management controller and the battery module. The energy management controller is connected to the switching element, the radiator, the electromagnetic reversing valve and the detection element.

3. The electric forklift energy management control system according to claim 2, characterized in that: The main contactor control circuit includes a main contactor, the positive terminal of the battery module is connected to one end of the contact of the main contactor through a discharge relay, the other end of the contact of the main contactor is connected to the positive terminal of the energy management controller, the two ends of the coil of the main contactor are respectively connected to the 2A11 and 2A12 ports of the energy management controller, and the negative terminal of the energy management controller is connected to the negative terminal of the battery module; The switch control circuit includes an emergency stop switch and a key switch. The positive end of the battery module is connected to one end of the emergency stop switch, the other end of the emergency stop switch is connected to one end of the key switch, and the other end of the key switch is connected to the key end of the energy management controller.

4. The electric forklift energy management control system according to claim 3, characterized in that: The electric forklift also includes a heater, and a DC-DC converter power-generating circuit is arranged between the heater, the battery module, and the energy management controller; the DC-DC converter power-generating circuit includes a DC-DC converter, a delay relay, and a heater switch, the positive end of the battery module is respectively connected to the positive input end of the DC-DC converter and one end of the contact of the delay relay through a discharge relay, the positive output end of the DC-DC converter is connected to one end of the heater switch and its C end is connected to the other end of the key switch, the other end of the heater switch is connected to one end of the coil of the delay relay, the other end of the coil of the delay relay is connected to the 2A3 port of the energy management controller, the other end of the contact of the delay relay is connected to the fan motor and PTC heater of the heater, and the fan motor and PTC heater of the heater are both connected to the negative end of the battery module.

5. The electric forklift energy management control system according to claim 4, characterized in that: The electric forklift energy management and control system also includes an interlocking relay; the PTC heater of the heater has gear one and gear two, and the working power of gear one is greater than the working power of gear two, the two ends of the coil of the interlocking relay are respectively connected to the 2A2 port of the energy management controller and the negative end of the battery module, one end of the normally closed contact and the normally open contact of the interlocking relay are both connected to the other end of the contact of the delay relay, and the other ends of the normally closed contact and the normally open contact of the interlocking relay are respectively connected to gear one and gear two of the PTC heater.

6. The electric forklift energy management control system according to claim 5, characterized in that: The electric forklift energy management and control system also includes a heater forced switch; one end of the heater forced switch is connected to the 2A4 port of the energy management controller and grounded, and the other end is connected to the other end of the delay relay coil.

7. The electric forklift energy management control system according to claim 2, characterized in that: The detection component includes temperature sensor 1 and temperature sensor 2. Temperature sensor 1 is used to detect the temperature of the cab of the electric forklift and is connected to the energy management controller. Temperature sensor 2 is used to detect the temperature of the hydraulic oil in the oil tank and is connected to the energy management controller.

8. The electric forklift energy management control system according to claim 4, characterized in that: The switching component includes a guide flap, a flip motor and a relay 1; the guide flap is installed on the output shaft of the flip motor, and in a default state, the guide flap covers the inner air inlet for external circulation; the two ends of the relay 1 coil are respectively connected to the 2A10 port of the energy management controller and the negative end of the battery module, and the two ends of the relay 1 contact are respectively connected to the positive output end of the DC-DC converter and the positive end of the flip motor, and the negative end of the flip motor is connected to the negative end of the battery module.

9. The electric forklift energy management control system according to claim 4, characterized in that: The electric forklift energy management and control system also includes relay 2, the two ends of the coil of relay 2 are respectively connected to the 2A5 port of the energy management controller and the negative end of the battery module, the two ends of the contact of relay 2 are respectively connected to the positive output end of the DC-DC converter and the positive end of the fan motor of the radiator, and the negative end of the fan motor of the radiator is connected to the negative end of the battery module.

10. The electric forklift energy management control system according to claim 9, characterized in that: The electric forklift energy management and control system also includes a three-way valve, which has an inlet and outlet one and outlet two connected to the inlet, the inlet is connected to the oil return port of the multi-way valve, and the outlet one and outlet two are respectively connected to the oil inlet of the fluid channel of the radiator and the oil return pipe of the oil tank, and an electromagnetic reversing valve for controlling the on-off between the inlet and outlet one and outlet two is arranged in the three-way valve, and the two ends of the coil of the electromagnetic reversing valve are respectively connected to the 2A5 port of the energy management controller and the negative end of the battery module.

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