Energy recovery system of loading machine and control method

Abstract

The energy recovery system of the loader comprises a transmission shaft, the transmission shaft is connected with a first transmission module used for collecting energy and a second transmission module used for braking, and a braking system is further arranged on one side of the transmission shaft; the system further comprises a control system, the control system comprises a whole vehicle controller, the input end of the whole vehicle controller is connected with a Hall pedal and a pressure sensor, and the output end of the whole vehicle controller is connected with an electromagnetic reversing valve in the system. According to different working conditions of the loader, different energy recovery and use modes are achieved, under the non-braking condition, mechanical movement of the loader in the advancing process is utilized, mechanical energy is converted into hydraulic energy and electric energy to be stored in the air bag type energy accumulator and the storage battery, energy recovery is conducted, and under the braking condition, energy is saved. The energy of the energy accumulator is released and the energy accumulator participates in braking by combining the actual braking condition and the pressure of the energy accumulator, so that the energy is recycled, the use efficiency of fuel is greatly improved, and the use cost is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of engineering machinery, and in particular to an energy recovery system and a control method for a loader. Background Art

[0002] At present, the brake system of the loader is to use high-pressure oil to push the brake piston, the brake piston pushes the friction plate, the friction plate presses the brake disc, and the brake disc is held by friction, so as to slow down or stop the vehicle. Although it is simple and easy to implement, the disadvantage is that the braking process will convert the vehicle's kinetic energy into heat energy of the friction plate. The compact structure of the friction plate will lead to poor heat dissipation. When braking frequently or over a long distance, it may cause the brake temperature to rise sharply. When the temperature exceeds the boiling point of the hydraulic oil or brake fluid, the brake will fail. In severe cases, major losses such as vehicle destruction and death may occur. At the same time, if the brake does not fail, as the brake disc temperature rises, the friction coefficient will decrease, the braking distance will increase, and other safety accidents will be caused. Summary of the invention

[0003] The technical problem to be solved by the present invention is to overcome the deficiencies of the above-mentioned prior art and provide an energy recovery system and control method for a loader with a simple structure and good effect.

[0004] The present invention is implemented by the following technical scheme: an energy recovery system for a loader, comprising a transmission shaft, the transmission shaft being connected with a first transmission module for collecting energy and a second transmission module for braking, and a braking system is also provided on one side of the transmission shaft; A first transmission module, comprising a transmission hydraulic pump and a first transmission device, wherein the first transmission device is mechanically connected to the transmission shaft and provides power for the transmission hydraulic pump, one side of the transmission hydraulic pump is connected to the hydraulic oil tank via an electromagnetic reversing valve I, and the other side of the transmission hydraulic pump is sequentially connected to an electromagnetic reversing valve II and an electromagnetic reversing valve IV, wherein the electromagnetic reversing valve II is connected to a hydraulic energy storage device, and the electromagnetic reversing valve IV is connected to an electric energy storage device; A second transmission module includes a transmission hydraulic motor and a second transmission device, wherein the second transmission device is mechanically connected to the transmission shaft, the transmission hydraulic motor is connected to the hydraulic energy storage device through the electromagnetic reversing valve IV and the electromagnetic reversing valve II, and the transmission hydraulic motor provides braking power for the second transmission device; The brake system is connected to the hydraulic oil tank via an electromagnetic reversing valve III; It also includes a control system, which includes a vehicle controller. The input end of the vehicle controller is connected to a Hall pedal and a pressure sensor, the Hall pedal is connected to a brake pedal, the pressure sensor is connected to a hydraulic energy storage device, and the output end of the vehicle controller is connected to an electromagnetic reversing valve I, an electromagnetic reversing valve II, an electromagnetic reversing valve III and an electromagnetic reversing valve IV.

[0005] It is further provided that: the brake system comprises a brake hydraulic pump, a hydraulic cylinder, a brake caliper and a drive axle chuck.

[0006] The hydraulic energy storage device includes a bladder accumulator.

[0007] The electric energy storage device includes a power generation hydraulic motor, a generator and a battery.

[0008] The electromagnetic reversing valve II is provided with four oil ports, namely oil port A, oil port B, oil port C and oil port D. The oil port A is connected to the first transmission module, the oil port D is connected to the electromagnetic reversing valve IV, and the oil ports B and C are connected to the hydraulic energy storage device.

[0009] The electromagnetic reversing valve IV is provided with four oil ports, namely oil port H, oil port I, oil port J and oil port K. The oil port H is connected to the electromagnetic reversing valve II, the oil port K is connected to the second transmission module, and the oil port I and oil port J are connected to the electric energy storage device.

[0010] A method for controlling an energy recovery system of a loader, including two working conditions of the loader, braking and non-braking; When the accelerator pedal is depressed, it is a non-braking condition and the system is in an energy recovery state. At this time, the transmission shaft is connected to the first transmission module to prepare for energy recovery. The vehicle controller collects the pressure sensor signal and the battery power state. If the pressure of the airbag accumulator is less than the pressure when the accumulator is fully loaded, or the battery is not fully charged, the airbag accumulator and the battery are stored, and the priority of the airbag accumulator storage is higher than the priority of the battery storage. When the accelerator pedal is not pressed and the brake pedal is pressed, it is the braking condition. The system releases the stored energy and participates in the braking state. The vehicle controller collects the Hall pedal information. If the output angle value of the Hall element is less than the braking threshold, the system uses the second transmission module for braking or the braking system for braking according to the accumulator pressure. If the output angle value of the Hall element is greater than the braking threshold, the system uses the braking system for braking or the second transmission module and the braking system for braking at the same time according to the accumulator pressure.

[0011] In non-braking conditions, if the pressure of the bladder accumulator is lower than the pressure when the accumulator is fully loaded, the bladder accumulator stores energy, and the electromagnetic reversing valve II changes its working position to open the connection with the bladder accumulator and closes the connection with the electromagnetic reversing valve IV; if the pressure of the bladder accumulator is higher than the pressure when the accumulator is fully loaded, the bladder accumulator does not need to store energy, and the electromagnetic reversing valve II changes its working position to close the connection with the bladder accumulator and opens the connection with the electromagnetic reversing valve IV.

[0012] In non-braking conditions, if the battery is not fully charged, the electromagnetic reversing valve IV changes its working position to open the connection with the generator hydraulic motor, and the generator hydraulic motor rotates to drive the generator to charge the battery; if the battery is fully charged, the electromagnetic reversing valve IV changes its working position to disconnect the generator hydraulic motor.

[0013] During braking conditions, if the accumulator pressure is greater than the no-load pressure, the transmission shaft is connected to the second transmission device, and the electromagnetic reversing valve II and the electromagnetic reversing valve IV change their working positions, so that the airbag accumulator is connected to the second transmission device through the electromagnetic reversing valve II and the electromagnetic reversing valve IV, and the hydraulic oil in the airbag accumulator enters the transmission hydraulic motor to drive the transmission hydraulic motor to rotate, and the hydraulic motor outputs reverse torque to brake the transmission shaft.

[0014] The present invention has the following advantages: an energy recovery system and control method for a loader of the present invention has different energy recovery and use modes according to different working conditions of the loader. In a non-braking situation, the mechanical movement of the loader during movement is utilized to convert mechanical energy into hydraulic energy and electrical energy and store them in an airbag accumulator and a battery to perform energy recovery. In a braking situation, the energy of the accumulator is released in combination with the actual braking situation and the pressure of the accumulator to participate in braking, thereby realizing energy recovery and reuse, greatly improving the use efficiency of fuel, effectively saving fuel, and reducing the use cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The accompanying drawings are part of the present invention and are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention, but do not constitute an improper limitation of the present invention. Obviously, the accompanying drawings described below are only some embodiments. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without creative work.

[0016] In the attached picture: Figure 1 It is a structural principle diagram of the present invention; Figure 2 It is the control principle diagram of the present invention.

[0017] It should be noted that these drawings and textual descriptions are not intended to limit the conceptual scope of the present invention in any way, but are intended to illustrate the concept of the present invention for those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. The following embodiments are used to illustrate the present invention but are not used to limit the scope of the present invention.

[0019] In the description of the present invention, it should be noted that the directions or positional relationships indicated by terms such as “upper”, “lower”, “front”, “back”, “left”, “right”, “vertical”, “inside” and “outside” are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0020] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0021] like Figure 1 The energy recovery system of a loader shown in the figure includes a transmission shaft, the transmission shaft is connected with a first transmission module for collecting energy and a second transmission module for braking, and a braking system is also provided on one side of the transmission shaft; the first transmission module includes a transmission hydraulic pump and a first transmission device, the first transmission device is mechanically connected to the transmission shaft and provides power for the transmission hydraulic pump, one side of the transmission hydraulic pump is connected to the hydraulic oil tank through an electromagnetic reversing valve I, and the other side of the transmission hydraulic pump is connected to an electromagnetic reversing valve II and an electromagnetic reversing valve IV in sequence, the electromagnetic reversing valve II is connected to a hydraulic energy storage device, and the electromagnetic reversing valve IV is connected to an electric energy storage device; the second transmission module includes a transmission hydraulic motor and a second transmission device, the second transmission device is mechanically connected to the transmission shaft, the transmission hydraulic motor is connected to the hydraulic energy storage device through an electromagnetic reversing valve IV and an electromagnetic reversing valve II, and the transmission hydraulic motor provides braking power for the second transmission device. The transmission shaft of the present invention connects the first transmission module and the second transmission module, and is connected or disconnected according to working conditions. The transmission shaft is connected to the first transmission module, and the mechanical energy of the loader during operation is converted into hydraulic energy and electrical energy through a hydraulic energy storage device and an electrical energy storage device and stored. When the second transmission module is needed to participate in braking, the second transmission module is connected to the transmission shaft, and the hydraulic energy in the hydraulic energy storage device is released to the second transmission module, driving the second transmission module to brake, thereby achieving the effect of energy recovery and utilization. Specifically, a driving wheel is provided on the transmission shaft, and the first transmission device and the second transmission device of the first transmission module and the second transmission module are two transmission wheels respectively. The connection and disconnection of the driving wheel and the two transmission wheels are controlled by the vehicle controller to achieve the connection and disconnection of the transmission shaft and the first transmission module and the second transmission module.

[0022] like Figure 1The energy recovery system of a loader shown in the figure, the braking system is connected to the hydraulic oil tank through the electromagnetic reversing valve III. The present invention retains the original braking system of the loader, which participates in the braking of the whole machine, and at the same time, under the action of the vehicle controller, cooperates with the second transmission module to brake the loader together, realizing the reasonable planning and utilization of energy.

[0023] like Figure 1 The energy recovery system of a loader shown in the figure also includes a control system, which includes a vehicle controller, the input end of the vehicle controller is connected to a Hall pedal and a pressure sensor, the Hall pedal is connected to a brake pedal, the pressure sensor is connected to a hydraulic energy storage device, and the output end of the vehicle controller is connected to an electromagnetic reversing valve I, an electromagnetic reversing valve II, an electromagnetic reversing valve III and an electromagnetic reversing valve IV. The control system of the present invention includes a vehicle controller, a Hall pedal, a pressure sensor, an electromagnetic reversing valve I, an electromagnetic reversing valve II, an electromagnetic reversing valve III and an electromagnetic reversing valve IV. The Hall pedal and the pressure sensor are used to collect signals from the brake pedal and the airbag accumulator, and transmit them to the vehicle controller. The vehicle controller outputs signals to the electromagnetic reversing valve I, the electromagnetic reversing valve II, the electromagnetic reversing valve III and the electromagnetic reversing valve IV according to the judgment, controls the action of each electromagnetic valve, realizes the control of the entire system, and completes the energy recovery and utilization.

[0024] like Figure 1 The energy recovery system of a loader shown in the figure comprises a brake hydraulic pump, a hydraulic cylinder, a brake caliper and a drive axle chuck. When the brake system of the present invention is used for braking, the hydraulic oil in the hydraulic oil tank enters the hydraulic cylinder under the action of the brake hydraulic pump, and the hydraulic cylinder drives the brake caliper to drive the drive chuck to operate, thereby achieving braking.

[0025] like Figure 1 The energy recovery system of a loader shown in the figure, the hydraulic energy storage device includes an airbag accumulator. The hydraulic energy storage device of the present invention mainly stores hydraulic energy through the airbag accumulator, and releases the stored hydraulic energy through the airbag accumulator. In addition, a pressure sensor is arranged on the airbag accumulator to detect the pressure of the airbag accumulator, so that the controller can judge whether to add the airbag accumulator to the work flow.

[0026] like Figure 1 The energy recovery system of a loader shown in the figure, the electric energy storage device includes a power generation hydraulic motor, a generator and a battery. The electric energy storage device of the present invention mainly drives the generator to operate through the power generation hydraulic motor, stores the electric energy in the battery, realizes the conversion of hydraulic energy into electric energy, and achieves the effect of recycling the system capacity.

[0027] like Figure 1In the energy recovery system of a loader shown in the figure, the solenoid reversing valve II is provided with four oil ports, namely, oil port A, oil port B, oil port C and oil port D. The oil port A is connected to the first transmission module, the oil port D is connected to the solenoid reversing valve IV, and the oil ports B and C are connected to the hydraulic energy storage device. The electromagnetic reversing valve II of the present invention is used to connect the first transmission module, the hydraulic energy storage device and the electromagnetic reversing valve IV. By locating the electromagnetic reversing valve II in different working positions, the conduction and closing between the three components are realized, so as to achieve the functions of storing energy for the hydraulic energy storage device, storing energy for the electric energy storage device and releasing the hydraulic energy of the hydraulic energy storage device; specifically, when the oil port A and the oil port B are opened and the oil port D is closed, the hydraulic oil enters the airbag accumulator through the electromagnetic reversing valve II under the action of the transmission hydraulic pump to store energy; when the oil port A and the oil port D are opened and the oil port B and the oil port C are closed, the passage for the hydraulic oil to enter the airbag accumulator is closed, so that the hydraulic oil enters the electromagnetic reversing valve IV through the electromagnetic reversing valve II; when the oil port C and the oil port D are opened and the oil port A and the oil port B are closed, the hydraulic oil in the airbag accumulator flows out and enters the second transmission module to participate in braking.

[0028] like Figure 1 The energy recovery system of a loader shown in the figure, the electromagnetic reversing valve IV is provided with four oil ports, namely oil port H, oil port I, oil port J and oil port K, the oil port H is connected to the electromagnetic reversing valve II, the oil port K is connected to the second transmission module, and the oil port I and oil port J are connected to the electric energy storage device. The electromagnetic reversing valve IV of the present invention connects the electromagnetic reversing valve II and the second transmission module, and the electromagnetic reversing valve IV is located in different working positions to realize the functions of storing energy for the electric energy storage device, closing the energy storage for the electric energy storage device, and conducting the electromagnetic reversing valve II and the second transmission module; specifically, when all the oil ports are opened, the energy storage operation of the electric energy storage device is performed, and when the oil ports H and oil port K are opened, and the oil ports I and oil port J are closed, the energy storage operation of the electric energy storage device is stopped.

[0029] like Figure 1 and Figure 2 The control method of the energy recovery system of a loader shown in the figure includes two working conditions of the loader, braking and non-braking. In the non-braking working condition, energy recovery is realized, and the recovered energy is hydraulic energy and electrical energy. In the braking working condition, the hydraulic energy is released to participate in braking, and energy recovery and reuse are completed. The specific operations are as follows: When the accelerator pedal is pressed, it is a non-braking condition and the system is in an energy recovery state. At this time, the drive shaft is connected to the first transmission module to prepare for energy recovery. The vehicle controller collects the pressure sensor signal and the battery power status. If the pressure of the airbag accumulator is less than the pressure when the accumulator is fully loaded, or the battery is not fully charged, the airbag accumulator and the battery are stored, and the priority of the airbag accumulator energy storage is higher than the priority of the battery energy storage.

[0030] In non-braking conditions, if the pressure of the bladder accumulator is less than the pressure when the accumulator is fully loaded, the bladder accumulator stores energy, and the electromagnetic reversing valve II changes its working position to open the connection with the bladder accumulator and closes the connection with the electromagnetic reversing valve IV; if the pressure of the bladder accumulator is greater than the pressure when the accumulator is fully loaded, the bladder accumulator does not need to store energy, and the electromagnetic reversing valve II changes its working position to close the connection with the bladder accumulator and conducts the connection with the electromagnetic reversing valve IV; In non-braking conditions, if the battery is not fully charged, the electromagnetic reversing valve IV changes its working position to open the connection with the generator hydraulic motor, and the generator hydraulic motor rotates to drive the generator to charge the battery; if the battery is fully charged, the electromagnetic reversing valve IV changes its working position to disconnect the generator hydraulic motor.

[0031] When the accelerator pedal is not pressed and the brake pedal is pressed, it is the braking condition. The system releases the stored energy and participates in the braking state. The vehicle controller collects the Hall pedal information. If the output angle value of the Hall element is less than the braking threshold, the system uses the second transmission module for braking or the braking system for braking according to the accumulator pressure. If the output angle value of the Hall element is greater than the braking threshold, the system uses the braking system for braking or the second transmission module and the braking system for braking at the same time according to the accumulator pressure.

[0032] During braking conditions, if the accumulator pressure is greater than the no-load pressure, the transmission shaft is connected to the second transmission device, and the electromagnetic reversing valve II and the electromagnetic reversing valve IV change their working positions, so that the airbag accumulator is connected to the second transmission device through the electromagnetic reversing valve II and the electromagnetic reversing valve IV, and the hydraulic oil in the airbag accumulator enters the transmission hydraulic motor to drive the transmission hydraulic motor to rotate, and the hydraulic motor outputs reverse torque to brake the transmission shaft.

[0033] like Figure 2 The control method of the energy recovery system of the loader shown in the figure specifically comprises the following steps: S1, check whether the accelerator pedal is pressed, if the accelerator pedal is pressed, go to S2, if the accelerator pedal is not pressed, go to S8; S2, the transmission shaft is connected to the first transmission device, and it is determined whether the pressure of the accumulator at this time is greater than the pressure when the accumulator is fully loaded. If so, go to S3; if not, go to S7; S3, the electromagnetic reversing valve I and the electromagnetic reversing valve II exchange working positions, the electromagnetic reversing valve I is turned on, the oil ports A and D of the electromagnetic reversing valve II are turned on, the oil ports B and C are closed, and the transmission hydraulic pump runs idle at this time; S4, judging whether the battery is fully charged at this time, if the battery is fully charged, go to S5, if the battery is not fully charged, go to S6; S5, the solenoid reversing valve IV changes its working position, the oil ports H and K are opened, the oil ports I and J are closed, and the hydraulic oil flows back to the hydraulic oil tank, ending this process; S6, the electromagnetic reversing valve IV changes its working position, the oil port H and the oil port I are opened, the hydraulic oil flows through the generator hydraulic motor and then flows back to the hydraulic oil tank. At this time, the generator hydraulic motor rotates under the action of the hydraulic oil, driving the generator to generate electricity and then charge the battery, ending this process; S7, the electromagnetic reversing valve I and the electromagnetic reversing valve II exchange working positions, the electromagnetic reversing valve I is turned on, the oil ports A and B are opened, the oil port D is closed, and the hydraulic oil flows into the bladder accumulator under the action of the transmission hydraulic pump, and this process ends; S8, the brake pedal is stepped on, and the angle of the brake pedal is determined. If the output angle of the Hall element in the Hall pedal is less than the brake threshold, go to S9; if the output angle of the Hall element is greater than the brake threshold, go to S12; S9, judging whether the pressure of the accumulator is greater than the no-load pressure at this time, if so, go to S10, if not, go to S11; S10, the transmission shaft is connected to the second transmission device, the electromagnetic reversing valve III becomes closed, the electromagnetic reversing valve II changes its working position, the oil port A is closed, and the oil ports C and D are opened; the electromagnetic reversing valve IV changes its working position, the oil ports H and K are opened, and the oil ports I and J are closed. At this time, the hydraulic oil in the bladder accumulator enters the transmission hydraulic motor under the action of the transmission hydraulic pump, driving the transmission hydraulic motor to rotate, and the transmission hydraulic motor outputs a reverse torque to brake the transmission shaft. At this time, only the transmission hydraulic motor brakes the loader, and this process ends; S11, at this time, the electromagnetic reversing valve III becomes the conducting state, and only the braking system brakes the loader, and this process ends; S12, judging whether the pressure of the accumulator is greater than the no-load pressure at this time, if so, go to S13, if not, go to S11; S13, solenoid reversing valve III becomes conductive, solenoid reversing valve II changes working position, oil port A is closed, and oil ports C and D are opened. At this time, the transmission hydraulic motor and the brake system jointly brake the loader.

[0034] The energy recovery system and control method of the loader of the present invention convert mechanical energy into hydraulic energy and electrical energy through a first transmission module and store them in an airbag accumulator and a battery, and convert the hydraulic energy in the accumulator into mechanical energy for braking the loader through a second transmission module, thereby effectively saving fuel. The energy stored in the accumulator and the braking system implement different braking strategies according to the different states of the loader's brake pedal, thereby being able to cope with various braking scenarios and saving energy while completing braking. The mechanical energy of the transmission shaft is rationally used to brake the loader, thereby improving the fuel efficiency of the entire machine and reducing the cost of use.

[0035] In the description provided herein, a large number of specific details are described. However, it is understood that embodiments of the present invention can be practiced without these specific details. In some instances, well-known methods, structures and techniques are not shown in detail so as not to obscure the understanding of this description.

[0036] In addition, those skilled in the art will understand that, although some embodiments described herein include certain features included in other embodiments but not other features, the combination of features of different embodiments also means being within the scope of protection of the present invention and forming different embodiments. For example, in the above embodiments, those skilled in the art can use them in combination according to the known technical solutions and the technical problems to be solved by this application.

[0037] The above is only a preferred embodiment of the present invention, and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technician familiar with this patent can make some changes or modify the technical contents suggested above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the solution of the present invention.

Claims

1. An energy recovery system for a loader, characterized in that: It includes a transmission shaft, the transmission shaft is connected with a first transmission module for collecting energy and a second transmission module for braking, and a braking system is also provided on one side of the transmission shaft; A first transmission module, comprising a transmission hydraulic pump and a first transmission device, wherein the first transmission device is mechanically connected to the transmission shaft and provides power for the transmission hydraulic pump, one side of the transmission hydraulic pump is connected to the hydraulic oil tank via an electromagnetic reversing valve I, and the other side of the transmission hydraulic pump is sequentially connected to an electromagnetic reversing valve II and an electromagnetic reversing valve IV, wherein the electromagnetic reversing valve II is connected to a hydraulic energy storage device, and the electromagnetic reversing valve IV is connected to an electric energy storage device; A second transmission module includes a transmission hydraulic motor and a second transmission device, wherein the second transmission device is mechanically connected to the transmission shaft, the transmission hydraulic motor is connected to the hydraulic energy storage device through the electromagnetic reversing valve IV and the electromagnetic reversing valve II, and the transmission hydraulic motor provides braking power for the second transmission device; The brake system is connected to the hydraulic oil tank via an electromagnetic reversing valve III; It also includes a control system, which includes a vehicle controller. The input end of the vehicle controller is connected to a Hall pedal and a pressure sensor, the Hall pedal is connected to a brake pedal, the pressure sensor is connected to a hydraulic energy storage device, and the output end of the vehicle controller is connected to an electromagnetic reversing valve I, an electromagnetic reversing valve II, an electromagnetic reversing valve III and an electromagnetic reversing valve IV.

2. The energy recovery system for a loader according to claim 1, characterized in that: The brake system comprises a brake hydraulic pump, a hydraulic oil cylinder, a brake caliper and a drive axle chuck.

3. The energy recovery system for a loader according to claim 1, characterized in that: The hydraulic energy storage device includes a bladder accumulator.

4. The energy recovery system for a loader according to claim 1, characterized in that: The electric energy storage device includes a power generation hydraulic motor, a generator and a battery.

5. The energy recovery system for a loader according to claim 1, characterized in that: The electromagnetic reversing valve II is provided with four oil ports, namely oil port A, oil port B, oil port C and oil port D. The oil port A is connected to the first transmission module, the oil port D is connected to the electromagnetic reversing valve IV, and the oil ports B and C are connected to the hydraulic energy storage device.

6. The energy recovery system for a loader according to claim 1, characterized in that: The electromagnetic reversing valve IV is provided with four oil ports, namely oil port H, oil port I, oil port J and oil port K. The oil port H is connected to the electromagnetic reversing valve II, the oil port K is connected to the second transmission module, and the oil port I and oil port J are connected to the electric energy storage device.

7. A control method for the energy recovery system of a loader using the method of claim 1, characterized in that: Includes two working conditions of the loader: braking and non-braking; When the accelerator pedal is depressed, it is a non-braking condition and the system is in an energy recovery state. At this time, the transmission shaft is connected to the first transmission module to prepare for energy recovery. The vehicle controller collects the pressure sensor signal and the battery power state. If the pressure of the airbag accumulator is less than the pressure when the accumulator is fully loaded, or the battery is not fully charged, the airbag accumulator and the battery are stored, and the priority of the airbag accumulator storage is higher than the priority of the battery storage. When the accelerator pedal is not pressed and the brake pedal is pressed, it is the braking condition. The system releases the stored energy and participates in the braking state. The vehicle controller collects the Hall pedal information. If the output angle value of the Hall element is less than the braking threshold, the system uses the second transmission module for braking or the braking system for braking according to the accumulator pressure. If the output angle value of the Hall element is greater than the braking threshold, the system uses the braking system for braking or the second transmission module and the braking system for braking at the same time according to the accumulator pressure.

8. The control method of the energy recovery system of a loader according to claim 7, characterized in that: In non-braking conditions, if the pressure of the bladder accumulator is lower than the pressure when the accumulator is fully loaded, the bladder accumulator stores energy, and the electromagnetic reversing valve II changes its working position to open the connection with the bladder accumulator and closes the connection with the electromagnetic reversing valve IV; if the pressure of the bladder accumulator is higher than the pressure when the accumulator is fully loaded, the bladder accumulator does not need to store energy, and the electromagnetic reversing valve II changes its working position to close the connection with the bladder accumulator and opens the connection with the electromagnetic reversing valve IV.

9. The control method of the energy recovery system of a loader according to claim 7, characterized in that: In non-braking conditions, if the battery is not fully charged, the electromagnetic reversing valve IV changes its working position to open the connection with the generator hydraulic motor, and the generator hydraulic motor rotates to drive the generator to charge the battery; if the battery is fully charged, the electromagnetic reversing valve IV changes its working position to disconnect the generator hydraulic motor.

10. The control method of the energy recovery system of a loader according to claim 7, characterized in that: During braking conditions, if the accumulator pressure is greater than the no-load pressure, the transmission shaft is connected to the second transmission device, and the electromagnetic reversing valve II and the electromagnetic reversing valve IV change their working positions, so that the airbag accumulator is connected to the second transmission device through the electromagnetic reversing valve II and the electromagnetic reversing valve IV, and the hydraulic oil in the airbag accumulator enters the transmission hydraulic motor to drive the transmission hydraulic motor to rotate, and the hydraulic motor outputs reverse torque to brake the transmission shaft.

Images