Excavator movable arm potential energy recycling and reusing system
By designing a boom potential energy recovery and reuse system in the excavator, and using servo motors to drive the quantitative pump/motor and mechanical structure to store the potential energy when the boom falls, the problem of low energy efficiency of the excavator hydraulic transmission system is solved, and efficient energy utilization and sustainable environmental development are achieved.
Patent Information
- Application Number
- CN202510351985.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-24
- Publication Date
- 2025-06-13
AI Technical Summary
The existing excavator hydraulic transmission system is inefficient, resulting in energy waste and environmental pollution. The potential energy released when the boom descends cannot be effectively recycled and reused.
A new potential energy recovery and reuse system for excavator booms is designed, and the metering pump/motor is driven by a servo motor to realize the power supply of the hydraulic system, and the potential energy of the boom when it descends through mechanical structure and electronic control system is stored, and it is converted into electrical energy for storage.
It significantly improves the energy efficiency of the excavator hydraulic transmission system, extends the working time of the entire machine, reduces the system installation power, and achieves efficient energy utilization and sustainable environmental development.
Smart Images
Figure CN120140320A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of construction machinery, and specifically relates to a boom potential energy recovery and reuse system for an excavator. Background Art
[0002] At present, an excavator usually uses an internal combustion engine to drive a hydraulic pump as a fluid power source, and a multi-way valve as a control element to distribute and transfer power to each hydraulic actuator. Since the engine is difficult to work in the high-efficiency fuel area for a long time, it results in a large fuel consumption, causing a large amount of energy waste and environmental pollution. In addition, when an excavator operates, it generally completes composite actions by multiple actuators. Due to the load differences acting on each actuator, the pressures in each oil chamber are different. In order to balance the pressures on different actuators, huge throttling losses are generated in the multi-way valve, resulting in low energy efficiency of the hydraulic system. Moreover, when the actuator of the excavator falls and rotates for braking, a large amount of kinetic and potential energy will be lost in the valve orifice throttling, not only causing a decrease in the overall machine efficiency but also making the system generate serious heat. During the working process of a traditional excavator, a large amount of potential energy is released when the boom descends. The gravitational potential energy wasted during the descent of the excavator boom is about 15% of the energy output by the hydraulic pump, and this energy usually dissipates in the form of heat or other forms of losses. Summary of the Invention
[0003] In order to improve the energy efficiency of the hydraulic transmission system of the excavator and extend the working duration of the whole machine, combined with the existing pump control energy-saving technology, a new type of boom potential energy recovery and reuse system for the excavator is proposed. A servo motor is used to drive a fixed-displacement pump / motor to supply energy to the hydraulic system, directly control the operation of the actuator, achieve high energy efficiency and greenness, and at the same time reduce the installed power of the system. Therefore, fully recovering and utilizing the gravitational potential energy plays an important role in improving the energy efficiency of the excavator hydraulic system. The boom potential energy recovery system can store the potential energy released when the boom descends through a series of mechanical structures and electronic control systems, convert it into electrical energy for storage, and thus realize the reuse of energy.
[0004] The electrification of construction machinery provides convenient conditions for the application of the electrical energy recovery and utilization method. The electrical recovery method converts the gravitational potential energy of the working device into electrical energy for storage through a hydraulic motor or a hydraulic pump / motor - generator. Aiming at the deficiencies of the existing electric excavators using a multi-way valve control system, such as low energy efficiency, large battery installed capacity but short battery life, the present invention proposes a boom potential energy recovery and reuse system for an excavator. The present invention adopts the following technical solutions: A new boom potential energy recovery and reuse system for an excavator, including a control circuit connected to an oil cylinder. In the control circuit, there are two pump control circuits corresponding to the rodless cavity and the rod cavity of the oil cylinder, namely the hydraulic pump / motor one pump control circuit I and the hydraulic pump / motor two pump control circuit II. The components of the pump control circuit include: hydraulic pump / motor one, hydraulic pump / motor two, non-spring check valve, spring check valve, proportional control valve, driver, bidirectional DC-DC, super capacitor, and controller. The hydraulic pump / motor one pump control circuit I is as follows: A non-spring check valve and a spring check valve are arranged in parallel in the circuit from the inlet of the hydraulic pump / motor one to the fuel tank. A non-spring check valve is connected between the inlet and outlet of the hydraulic pump / motor one. The outlet of the hydraulic pump / motor one is connected to the rodless cavity of the oil cylinder and is also respectively connected to the inlets of two proportional control valves. The outlets of the two proportional control valves are respectively connected to the inlets of the hydraulic pump / motor one and the hydraulic pump / motor two. The hydraulic pump / motor two pump control circuit II has the same configuration and connection as the hydraulic pump / motor one pump control circuit I. The outlet of the hydraulic pump / motor two is connected to the rod cavity of the oil cylinder and is also respectively connected to the inlets of two proportional control valves. The outlets of the two proportional control valves are respectively connected to the inlets of the hydraulic pump / motor one and the hydraulic pump / motor two. The motor 1 coaxially drives the hydraulic pump / motor one and the hydraulic pump / motor two. The motor is connected to a driver. The driver is connected to a bidirectional DC-DC. The bidirectional DC-DC is connected to a super capacitor and a controller. The controller is respectively connected to the proportional control valves.
[0005] Further, it also includes pressure sensors. Pressure sensors are respectively arranged at the outlets of the hydraulic pump / motor one and the hydraulic pump / motor two. The controller is respectively connected to the pressure sensors.
[0006] Further, it also includes a unidirectional fixed-differential pressure reducing valve. The rodless cavity of the oil cylinder is sequentially connected to a proportional control valve and a unidirectional fixed-differential pressure reducing valve. The outlet of the unidirectional fixed-differential pressure reducing valve is connected to the rod cavity of the oil cylinder.
[0007] Further, the proportional control valve is a proportional flow control valve and / or a proportional direction control valve.
[0008] Further, the proportional flow control valve includes proportional flow control valve one, proportional flow control valve two, proportional flow control valve three, proportional flow control valve four, and proportional flow control valve five. The outlet of the hydraulic pump / motor one is respectively connected to proportional flow control valve one, proportional flow control valve two, and proportional flow control valve five. The outlet of the hydraulic pump / motor two is connected to proportional flow control valve three and proportional flow control valve four. The outlets of proportional flow control valve one and proportional flow control valve two are respectively connected to the inlets of the hydraulic pump / motor one and the hydraulic pump / motor two. The outlets of proportional flow control valve three and proportional flow control valve four are respectively connected to the inlets of the hydraulic pump / motor one and the hydraulic pump / motor two. The outlet of proportional flow control valve five is connected to the unidirectional fixed-differential pressure reducing valve.
[0009] Further, it also includes an overflow valve, and the outlets of the hydraulic pump / motor 1 and the hydraulic pump / motor 2 are respectively connected to the installed overflow valve.
[0010] The opening pressure of the non-spring one-way valve is zero, and the opening pressure of the spring-loaded one-way valve exists.
[0011] Compared with the prior art, the present invention can achieve the following technical effects: The present invention provides a boom potential energy recovery and reuse system for an excavator. During the boom lowering process, the oil in the rodless cavity of the oil cylinder drives the hydraulic pump / motor to rotate, drives the coaxial motor to generate electricity, and can store the electricity. This system has a significant energy-saving effect.
[0012] In the present invention, a non-spring one-way valve is installed in the inlet and outlet oil ports of the hydraulic pump / motor to prevent the phenomenon of cavitation caused by the flow rate of the pump / motor not being able to keep up during the movement of the oil cylinder. When the boom of the excavator descends, the proportional flow control valve opens, and a part of the oil flows into the inlet oil port of the oil pump / motor 2. At this time, the oil opens the non-spring one-way valve and enters the rod chamber of the oil cylinder for flow regeneration and utilization; another part of the oil drives the motor to rotate and generate electricity through the pump / motor 1 for energy recovery.
[0013] When the piston of the oil cylinder extends, by controlling the proportional flow control valve, the operating load of the oil cylinder is reduced, and the installed power of the motor is lowered; when the piston retracts, by controlling the proportional flow control valve at the inlet and outlet of the hydraulic pump / motor 2, the power of the boom potential energy is increased. Description of the Drawings
[0014] Figure 1 is the hydraulic schematic diagram of the present invention.
[0015] Among them, 1 - motor, 2 - hydraulic pump / motor 1, 3 - hydraulic pump / motor 2, 4 - non-spring one-way valve, 5 - spring-loaded one-way valve, 601 - proportional flow control valve 1, 602 - proportional flow control valve 2, 603 - proportional flow control valve 3, 604 - proportional flow control valve 4, 605 - proportional flow control valve 5, 7 - overflow valve, 8 - oil cylinder, 9 - driver, 10 - bidirectional DC-DC, 11 - super capacitor, 12 - controller, 13 - fuel tank, 14 - pressure sensor, 15 - one-way fixed-differential pressure reducing valve. Detailed Embodiments
[0016] Such as Figure 1, shown is a new type of boom potential energy recovery and reuse system for an excavator, including an electric motor 1, a hydraulic pump / motor 1 2, a hydraulic pump / motor 2 3, a non-spring check valve 4, a spring-loaded check valve 5, a proportional control valve, a relief valve 7, an oil cylinder 8, a driver 9, a bidirectional DC-DC 10, a super capacitor 11, a controller 12, a fuel tank 13, a pressure sensor 14, a unidirectional fixed-differential pressure reducing valve 15. The proportional control valve includes a proportional flow control valve 1 601, a proportional flow control valve 2 602, a proportional flow control valve 3 603, a proportional flow control valve 4 604, and a proportional flow control valve 5 605. There are two pump control circuits corresponding to the rod chamber and the non-rod chamber of the oil cylinder 8, namely the pump control circuit I of the hydraulic pump / motor 1 2 and the pump control circuit II of the hydraulic pump / motor 2 3. Among them, the pump control circuit I of the hydraulic pump / motor 1 2 includes: a non-spring check valve 4 and a spring-loaded check valve 5 are connected in parallel in the circuit from the inlet of the hydraulic pump / motor 1 2 to the fuel tank 13. A non-spring check valve 4 is connected between the inlet and the outlet of the hydraulic pump / motor 1 2. The outlet of the hydraulic pump / motor 1 2 is connected to the non-rod chamber of the oil cylinder 8 and is also respectively connected with a proportional flow control valve 1 601, a proportional flow control valve 2 602, and a proportional flow control valve 5 605. When the proportional flow control valve 1 601 and the proportional flow control valve 2 602 work, a closed system is formed and is also used for oil replenishment to prevent air suction in the system and achieve the purpose of reducing the volume of the fuel tank. The outlet of the hydraulic pump / motor 1 2 is connected with a relief valve 7 and a pressure sensor 14, and the outlet of the relief valve 7 is connected to the fuel tank 13. The pump control circuit II of the hydraulic pump / motor 2 3 has the same configuration and connection as the pump control circuit I of the hydraulic pump / motor 1 2. In the pump control circuit II of the hydraulic pump / motor 2 3: the proportional flow control valve 3 603 and the proportional flow control valve 4 604 are equivalent to the proportional flow control valve 1 601 and the proportional flow control valve 2 602, and the hydraulic pump / motor 2 3 is equivalent to the hydraulic pump / motor 1 2; The electric motor 1 coaxially drives the hydraulic pump / motor 1 2 and the hydraulic pump / motor 2 3. The outlet of the hydraulic pump / motor 2 3 is connected to the rod chamber of the oil cylinder 8 and is also respectively connected with a proportional flow control valve 3 603 and a proportional flow control valve 4 604. The other port of the proportional flow control valve 1 601 is connected to the inlet of the hydraulic pump / motor 1 2 and the proportional flow control valve 3 603. The other port of the proportional flow control valve 2 602 is connected to the inlet of the hydraulic pump / motor 2 3 and the proportional flow control valve 4 604. The other port of the proportional flow control valve 5 605 is connected to the unidirectional fixed-differential pressure reducing valve 15, and the outlet of the unidirectional fixed-differential pressure reducing valve 15 is connected to the rod chamber of the oil cylinder 8; The overflow valve 7 prevents the system from overloading; the non-spring one-way valve 4 has an opening pressure of zero, and the spring-loaded one-way valve 5 has an opening pressure. A driver 9 is set for connection to the motor 1. The driver 9 is set to connect to a bidirectional DC-DC 10, the bidirectional DC-DC 10 is connected to a super capacitor 11, and a controller 12. The controller 12 is respectively connected to a proportional flow control valve 601, a proportional flow control valve 602, a proportional flow control valve 603, a proportional flow control valve 604, a proportional flow control valve 605, a pressure sensor 14, and the driver 9.
[0017] By configuring the displacements of two hydraulic pumps / motors, the flow rate matching of the boom hydraulic cylinder, i.e., the oil cylinder 8, and the drive without throttling loss are achieved. When the excavator boom descends, the oil in the rodless chamber of the oil cylinder 8 is discharged to the hydraulic pump / motor 1, and the hydraulic pump / motor 2 discharges oil to the rod chamber of the oil cylinder 8, pushing the piston of the oil cylinder 8 to retract. The oil in the rodless chamber of the oil cylinder 8 drives the hydraulic pump / motor 1 to rotate, and then drives the motor 1 to rotate. At this time, the motor 1 becomes a generator, generating electrical energy and storing it in the super capacitor 11. The super capacitor 11 electrically recovers the remaining gravitational potential energy of the working device. At this time, it is the hydraulic pump / motor 1 that drives the motor 1 and the hydraulic pump / motor 2 to do work, and not all of the boom potential energy can be recovered because a part of the potential energy is used to drive the hydraulic pump / motor 2. When the proportional flow control valve 604 is fully opened, the pressure difference between the inlet and outlet ports of the hydraulic pump / motor 2 becomes zero, that is, the hydraulic pump / motor 2 idles, enabling the boom gravitational potential energy to be completely converted into electrical energy through the hydraulic pump / motor 1. The new boom potential energy recovery system and its process are as follows.
[0018] 1. Working principle (process of energy recovery) The motor 1 coaxially drives the hydraulic pump / motor 1 and the hydraulic pump / motor 2. The proportional flow control valve 603 and the proportional flow control valve 604 are respectively connected to the inlet port of the hydraulic pump / motor 2 and the inlet port of the hydraulic pump / motor 1. When the proportional flow control valve 603 and the proportional flow control valve 604 are working, the system forms a closed system and is also used for oil replenishment to prevent the system from sucking air and achieve the purpose of reducing the volume of the fuel tank. An overflow valve 7 is installed in each chamber of the oil cylinder 8 to prevent the system from overloading; a one-way fixed-differential pressure reducing valve 15 and a proportional flow control valve 605, and the rod chamber of the oil cylinder 8 can conduct unidirectionally to the rodless chamber and is cut off in the reverse direction.
[0019] The ratio of the sum of the displacements of the hydraulic pump / motor 1 and the hydraulic pump / motor 2 to the displacement of the hydraulic pump / motor 2 is equal to the ratio of the area of the rodless chamber to the rod chamber of the oil cylinder 8. By matching the displacements of the hydraulic pump / motor 1 and the hydraulic pump / motor 2 and adjusting the speed of the motor 1, the flow rate matching and speed control of the oil cylinder 8 are achieved. The relationship between the displacement ratio of the hydraulic pump / motor 1 and the hydraulic pump / motor 2 and the area of the oil cylinder 8 is q 1 =A P q 2 B P Where: AP is the area of the rodless chamber of the hydraulic cylinder; BP is the area of the rod chamber of the hydraulic cylinder; q1 is the displacement of hydraulic pump / motor one; q2 is the displacement of hydraulic pump / motor two.
[0020] The working modes of an excavator are generally divided into light load and heavy load. In order to better and reasonably save energy and reduce emissions, the present invention designs a boom potential energy recovery and reuse system based on a differential circuit. The specific working process is as follows: Heavy load energy-saving working mode 1.1 Boom lowering During the boom lowering process, when the proportional flow control valve one 601, the proportional flow control valve two 602, the proportional flow control valve three 603, the proportional flow control valve four 604, and the proportional flow control valve five 605 are not opened, due to the gravitational potential energy of the load, the oil cylinder 8 functions as a single plunger pump. Part of the oil in the rod chamber of the oil cylinder 8 flows from the hydraulic pump / motor two 3, and the other part is supplemented with oil through the non-spring check valve 4. When the resistance of the oil passing through the hydraulic pump / motor two 3 is greater than that of the non-spring check valve 4, the oil mainly supplements the system through the non-spring check valve 4. The oil enters the rod chamber of the oil cylinder 8 through the two non-spring check valves 4, reducing the resistance of the hydraulic pump / motor two 3 to rotate and work, and improving the efficiency of boom potential energy recovery; when the proportional flow control valve three 603 and the proportional flow control valve four 604 are energized and opened, the oil discharged from the hydraulic pump / motor one 2 will also flow into the rod chamber of the oil cylinder 8 through this valve for oil supplement; at the same time, the pressure difference between the inlet and outlet of the hydraulic pump / motor two 3 is zero, causing the hydraulic pump / motor two 3 to idle and not do work. The oil in the rodless chamber of the oil cylinder 8 is discharged through the hydraulic pump / motor one 2 and drives the motor 1 to rotate and generate electricity. At this time, all the gravitational potential energy of the boom is converted into electrical energy for storage.
[0021] 1.2 Boom rising During the boom raising process, in the case of heavy load, the speed of the oil cylinder will be greatly reduced. When the proportional flow control valve 1 - 601, proportional flow control valve 2 - 602, proportional flow control valve 3 - 603, proportional flow control valve 4 - 604, and proportional flow control valve 5 - 605 are not opened, the relief valve 7 will generate some overflow losses, converting hydraulic energy into heat energy. The controller 12 controls and adjusts the driver 9 to match the rotational speed of the motor 1 with the required operating speed of the load, reducing the system flow rate and minimizing overflow losses. At this time, the controller 12 sends a signal to energize and open the proportional flow control valve 4 - 604. A part of the oil in the rod chamber of the oil cylinder 8 will flow into the oil port of the hydraulic pump / motor 2 - 3, reducing the pressure difference between its inlet and outlet ports to zero and causing it to idle, achieving the purpose of reducing the driving power of the motor 1, that is, reducing the electrical energy required for the motor 1 to drive the hydraulic pump / motor. At the same time, if, on the basis of the controller 12 controlling the proportional flow control valve 4 - 604 to be energized and opened, the proportional flow control valve 3 - 603 is also energized and opened, the oil in the rod chamber of the oil cylinder 8 flows into the suction port of the hydraulic pump / motor 1 - 2 through the proportional flow control valve 3 - 603. At this time, the pressure at the suction port of the hydraulic pump / motor 1 - 2 is stabilized by the spring check valve 5. The pressure difference between the inlet and outlet ports of the hydraulic pump / motor 1 - 2 is reduced, and the power for the motor 1 to drive the hydraulic pump / motor is decreased, achieving the purpose of the installed power of the hydraulic system.
[0022] Light load energy-saving working mode When the excavator is working under light load conditions, the oil cylinder 1 will have frequent commutation, which leads to commutation shock and energy loss. When the oil cylinder 8 extends, the motor 1 drives the hydraulic pump / motor 1 - 2 and the hydraulic pump / motor 2 - 3 to rotate. The oil flows into the rodless chamber of the oil cylinder 8 through the hydraulic pump / motor 1 - 2. The oil in the rod chamber of the boom cylinder 8 is discharged back to the fuel tank through the hydraulic pump / motor 2 - 3. At this time, there is no energy recovery. During the boom raising process, in the case of light load, the speed of the oil cylinder is relatively fast. The present invention uses a variable-speed motor 1 to adjust the rotational speed of the motor 1 to match the flow rate under light load conditions to meet the power required for the oil cylinder 1 to drive the load. The controller 12 opens the proportional flow control valve 5 - 605, and the other proportional flow control valves 1 - 601, 2 - 602, 3 - 603, and 4 - 604 are not energized. At this time, a part of the oil in the rod chamber of the oil cylinder 8 flows back to the fuel tank through the hydraulic pump / motor 2 - 3; another part of the oil flows into the rodless chamber of the oil cylinder 8 through the check valve of the one-way fixed differential pressure reducing valve 15, increasing the speed of the oil cylinder and reducing the driving power of the motor, achieving the purpose of reducing the installed power of the motor and saving energy.
[0023] When the boom retracts rapidly, there is a large amount of oil in the rodless cavity of the oil cylinder 8 and it cannot be discharged through the hydraulic pump / motor-2 in time, which will cause a large impact. If the proportional flow control valve-601 is not opened, the relief valve 7 will cause overflow loss and result in waste of energy. At this time, the oil in the rod cavity of the oil cylinder 8 cannot be discharged into the hydraulic pump / motor-3 in time, but is filled with oil through two zero-opening-pressure springless one-way valves 4. When the proportional flow control valve-601 and the proportional flow control valve-602 are energized and opened, the oil with impact energy in the rodless cavity of the oil cylinder 8 is released and flows into the inlet of the hydraulic pump / motor-3. It flows into the rod cavity of the oil cylinder 8 through the springless one-way valve 4. At this time, the pressure difference between the inlet and outlet of the hydraulic pump / motor-3 decreases, that is, the load driving the hydraulic pump / motor-2 is reduced, the energy conversion efficiency is improved, the regenerative utilization of the flow is realized, the driving power of the hydraulic pump / motor-3 is reduced, that is, the purpose of energy conservation and emission reduction is achieved.
[0024] The power source and energy recovery part of the present invention are integrated, that is, the motor coaxially drives the double hydraulic pump / motors. During the lowering process of the boom, the oil in the rodless cavity of the oil cylinder 8 drives the hydraulic pump / motor-2 to rotate, and the hydraulic pump / motor-2 drives the coaxial motor 1 to generate electricity. Since the proportional flow control valve-604 is energized and opened, the pressure difference between the inlet and outlet of the hydraulic pump / motor-3 is zero. Therefore, the potential energy of the boom is basically only used to drive the hydraulic pump / motor-2 to do work. This work makes the motor 1 generate electricity and store it in the super capacitor 11. This system has a significant energy-saving effect.
[0025] In the present invention, springless one-way valves are installed in the inlet and outlet ports of the hydraulic pump / motor to prevent cavitation caused by the inability of the flow of the hydraulic pump / motor to keep up with the movement of the oil cylinder. At the same time, the regenerative utilization of the flow can also be realized. For example, when the boom of the excavator descends, the oil at this time opens the springless one-way valve 4 and enters the rod cavity of the oil cylinder to prevent cavitation and achieve the purpose of oil filling; when the proportional flow control valve-602 is not opened and the proportional flow control valves-603 and -604 are opened, the hydraulic pump / motor-2 discharges oil with a certain pressure into the rod cavity of the oil cylinder 8, realizing the regenerative utilization of the flow, reducing the driving power of the hydraulic pump / motor-3, that is, achieving the purpose of energy conservation and emission reduction.
[0026] In the present invention, a one-way fixed-differential pressure reducing valve 15 is added. In light-load working conditions, when the oil cylinder 8 needs to act quickly, springless one-way valves 4 are installed in the inlet and outlet ports of the hydraulic pump / motor-2 and the hydraulic pump / motor-3 to prevent cavitation caused by the inability of the flow of the hydraulic pump / motor to keep up with the movement of the oil cylinder 8. At the same time, when the piston of the oil cylinder 8 extends out quickly, the one-way circuit in the one-way fixed-differential pressure reducing valve 15 is opened, making the circuit of the oil cylinder 8 a differential circuit, increasing the speed of the piston of the oil cylinder 8, improving the working efficiency of the excavator and saving costs.
[0027] An excavator equipped with a new boom potential energy recovery system based on a differential circuit can achieve efficient energy utilization, reduce dependence on traditional energy sources, and also lower carbon emissions and environmental pollution, in line with the concept of sustainable development. The research and development and application of this technology will have a positive impact on the excavator industry and promote the development of the construction machinery field towards a more environmentally friendly and intelligent direction.
Claims
1. A novel excavator boom potential energy recovery and reuse system, comprising a control circuit connected to an oil cylinder (8), characterized in that: Two pump control circuits are provided in the control circuit corresponding to the rod chamber and the rodless chamber of the oil cylinder (8), namely, hydraulic pump / motor one (2) pump control circuit I and hydraulic pump / motor two (3) pump control circuit II. The pump control circuit components include: A hydraulic pump / motor 1 (2), a hydraulic pump / motor 2 (3), a non-spring check valve (4), a spring check valve (5), a proportional control valve, a driver (9), a bidirectional DC-DC (10), a super capacitor (11), and a controller (12). A pump control circuit I of the hydraulic pump / motor 1 (2) is as follows: a non-spring check valve (4) and a spring check valve (5) are arranged in parallel in a circuit from the oil inlet of the hydraulic pump / motor 1 (2) to the oil tank (13). A non-spring check valve (4) is arranged between the oil inlet and the oil outlet of the hydraulic pump / motor 1 (2). The oil outlet of the hydraulic pump / motor 1 (2) is connected to the rodless chamber of the oil cylinder (8). Two proportional control valve inlets are also connected thereto. The two proportional control valve outlets are respectively connected to the hydraulic pump / motor 1 (2). , the inlet of hydraulic pump / motor 2 (3), the configuration and connection composition of the pump control circuit II of hydraulic pump / motor 2 (3) are the same as those of the pump control circuit I of hydraulic pump / motor 1 (2), the oil outlet of hydraulic pump / motor 2 (3) is connected to the rod chamber of the oil cylinder (8), and is also respectively connected to two proportional control valve inlets, the two proportional control valve outlets are respectively connected to the inlets of hydraulic pump / motor 1 (2) and hydraulic pump / motor 2 (3), the motor (1) coaxially drives the hydraulic pump / motor 1 (2) and the hydraulic pump / motor 2 (3), the motor (1) is connected to a driver (9), the driver (9) is connected to a bidirectional DC-DC (10), the bidirectional DC-DC (10) is connected to a super capacitor (11), a controller (12), and the controller (12) is respectively connected to the proportional control valve.
2. According to claim 1, a novel excavator boom potential energy recovery and reuse system is characterized in that: It also includes a pressure sensor (14), the outlets of the hydraulic pump / motor 1 (2) and the hydraulic pump / motor 2 (3) are respectively connected to the pressure sensor (14), and the controller (12) is respectively connected to the pressure sensor (14).
3. A novel excavator boom potential energy recovery and reuse system according to claim 2, characterized in that: It also includes a one-way differential pressure reducing valve (15), the rodless chamber of the oil cylinder (8) is connected in sequence to a proportional control valve and the one-way differential pressure reducing valve (15), and the outlet of the one-way differential pressure reducing valve (15) is connected to the rod chamber of the oil cylinder (8).
4. A novel excavator boom potential energy recovery and reuse system according to claim 3, characterized in that: The proportional control valve is a proportional flow control valve and / or a proportional reversing valve.
5. The novel excavator boom potential energy recovery and reuse system according to claim 4 is characterized in that: The proportional flow control valve comprises a proportional flow control valve 1 (601), a proportional flow control valve 2 (602), a proportional flow control valve 3 (603), a proportional flow control valve 4 (604), and a proportional flow control valve 5 (605). The oil outlet of the hydraulic pump / motor 1 (2) is respectively connected to the proportional flow control valve 1 (601), the proportional flow control valve 2 (602), and the proportional flow control valve 5 (605). The outlet of the hydraulic pump / motor 2 (3) is connected to the proportional flow control valve 3 (603) and the proportional flow control valve 4 (604). The outlets of the proportional flow control valve 1 (601) and the proportional flow control valve 2 (602) are respectively connected to the inlets of the hydraulic pump / motor 1 (2) and the hydraulic pump / motor 2 (3). The outlets of the proportional flow control valve 3 (603) and the proportional flow control valve 4 (604) are respectively connected to the inlets of the hydraulic pump / motor 1 (2) and the hydraulic pump / motor 2 (3). The outlet of the proportional flow control valve 5 (605) is connected to a one-way differential pressure reducing valve (15).
6. The novel excavator boom potential energy recovery and reuse system according to claim 1 is characterized in that: It also includes an overflow valve (7), and the outlets of the hydraulic pump / motor 1 (2) and the hydraulic pump / motor 2 (3) are respectively connected to the overflow valve (7).
7. The novel excavator boom potential energy recovery and reuse system according to claim 1 is characterized in that: The opening pressure of the non-spring check valve (4) is zero, while the opening pressure of the spring check valve (5) is present.