A hydraulic potential energy recovery and utilization system

Abstract

The present invention discloses a hydraulic potential energy recovery and utilization system, including a driving oil cylinder, a flow regeneration unit and a balancing unit, wherein the driving oil cylinder is used to drive a lifting device; the flow regeneration unit includes a motor, a main pump, an oil tank, a relief valve, two one-way valves, two throttle valves, and an electromagnetic reversing valve; the motor is coaxially connected to the main pump; the relief valve is installed at the oil outlet of the main pump to control the working pressure of the system; two throttle valves and two one-way valves are installed between the electromagnetic reversing valve and the main pump, and flow regeneration is achieved by increasing the return oil pressure of the rodless chamber of the driving oil cylinder; the balancing unit includes a balancing oil cylinder, three electromagnetic reversing valves, a hydraulic accumulator, and a relief valve, which are used to realize the recovery, storage and utilization of the potential energy of the lifting device. In the present invention, the recovery and utilization of the potential energy of the lifting device adopt the same oil circuit, and the main pump does not need to provide oil when the lifting device descends, the operation is simple, the operation is safe and reliable, and the energy utilization rate is high.

Description

Technical Field

[0001] The invention belongs to the field of hydraulic transmission, in particular to a hydraulic potential energy recovery and utilization system. Background Art

[0002] In order to reduce the labor intensity of manual labor, hydraulic excavators, hydraulic forklifts and other machines use hydraulic cylinders to drive lifting devices to complete specific lifting operations. These lifting devices frequently move up and down under the drive of hydraulic cylinders. During the descent process, the potential energy of the lifting device is dissipated in the form of heat energy at the throttle valve port, which can easily cause system heating, vibration and reduce the service life of components. If the potential energy of the lifting device is recovered and utilized, the energy consumption of the system can be effectively reduced, achieving the purpose of energy saving.

[0003] At present, there are some solutions for the recovery and utilization of potential energy of lifting devices. According to the different energy storage elements, it can be divided into electric and hydraulic potential energy recovery and utilization systems. The electric potential energy recovery and utilization system stores the potential energy of the lifting device in the form of electrical energy in the battery or supercapacitor by adding an energy recovery unit composed of components such as a hydraulic motor, a generator, a battery or a supercapacitor to the return oil circuit of the driving cylinder, such as patents 201620537294.6 and 200820166582.0; however, the recovery and utilization of potential energy in the system uses two different oil circuits, and when the lifting device descends, the main pump still needs to provide oil, and there are many energy conversion links. The hydraulic potential energy recovery and utilization system stores the potential energy of the lifting device in the form of liquid energy in the hydraulic accumulator by adding an energy recovery unit composed of a hydraulic accumulator, a hydraulic motor, a reversing valve, a throttle valve and other components to the return oil circuit of the driving cylinder, such as patents 201310103144.5 and 201210080014.X; however, it does not solve the problem that the recovery and utilization of the potential energy of the lifting device uses two different oil circuits and the main pump still needs to provide oil when the lifting device descends. Summary of the invention

[0004] In order to solve the deficiencies of the above-mentioned technologies, the present invention provides a hydraulic potential energy recovery and utilization system.

[0005] In order to make up for the shortcomings of the prior art, the present invention is achieved in the following way: a hydraulic potential energy recovery and utilization system, including a driving cylinder, a flow regeneration unit and a balancing unit; the driving cylinder is used to drive a lifting device; the flow regeneration unit includes an electric motor, a main pump, an oil tank, an overflow valve 1, a check valve 1, a check valve 2, a throttle valve 1, a throttle valve 2, and an electromagnetic reversing valve 1; the balancing unit includes a balancing cylinder, an electromagnetic reversing valve 2, an electromagnetic reversing valve 3, an electromagnetic reversing valve 4, an overflow valve 2, and a hydraulic accumulator.

[0006] Preferably, the main pump is coaxially connected to the motor, and the main pump is driven by the motor to provide the oil required by the system.

[0007] Preferably, the oil outlet of the main pump is divided into two paths, the first path is connected to the oil inlet of the overflow valve 1, the second path is connected to the oil inlet of the one-way valve 1, and the oil outlet of the overflow valve 1 is connected to the oil tank; the oil outlet of the one-way valve 1 is divided into three paths, the first path is connected to the oil outlet of the one-way valve 2, the second path is connected to the oil inlet of the throttle valve 1, and the third path is connected to the P port of the electromagnetic reversing valve 1; the oil outlet of the throttle valve 1 is connected to the oil tank; the A port of the electromagnetic reversing valve 1 is connected to the rod chamber of the driving cylinder, the B port is connected to the rodless chamber of the driving cylinder, and the T port is divided into two paths, the first path is connected to the oil inlet of the one-way valve 2, and the second path is connected to the oil inlet of the throttle valve 2; the oil outlet of the throttle valve 2 is connected to the oil tank to form a flow regeneration unit oil circuit.

[0008] Preferably, the relief valve 1 is used to control the pressure of the main pump.

[0009] Preferably, the rodless chamber of the balancing oil cylinder is connected to the P port of the electromagnetic reversing valve 2, the A port of the electromagnetic reversing valve 2 is connected to the P port of the electromagnetic reversing valve 4, and the B port of the electromagnetic reversing valve 2 is connected to the oil tank; the A port of the electromagnetic reversing valve 4 is divided into two paths, the first path is connected to the oil inlet of the hydraulic accumulator, and the second path is connected to the oil inlet of the overflow valve 2; the oil outlet of the overflow valve 2 is connected to the oil tank; the rod chamber of the balancing oil cylinder is connected to the P port of the electromagnetic reversing valve 3, the A port of the electromagnetic reversing valve 3 is connected to the P port of the electromagnetic reversing valve 4, and the B port of the electromagnetic reversing valve 3 is connected to the oil tank, forming a balancing unit oil circuit to realize the recovery, storage and utilization of the potential energy of the lifting device.

[0010] Preferably, the relief valve 2 is used to control the maximum working pressure of the hydraulic accumulator.

[0011] In the above manner, when the lifting device descends, the throttle valve 1 opens to an opening corresponding to the descending speed of the lifting device, the valve port of the throttle valve 2 is closed, and the electromagnetic reversing valve 1 and the electromagnetic reversing valve 2 work in the right position, that is, the P port of the electromagnetic reversing valve 1 is connected to the A port, the T port is connected to the B port, and the P port of the electromagnetic reversing valve 2 is connected to the A port. The electromagnetic reversing valve 3 and the electromagnetic reversing valve 4 work in the left position, that is, the P port of the electromagnetic reversing valve 3 is connected to the B port, and the P port of the electromagnetic reversing valve 4 is connected to the A port. The oil in the rodless chamber of the balancing oil cylinder is introduced into the hydraulic accumulator through the electromagnetic reversing valve 2 and the electromagnetic reversing valve 4 to realize the recovery and storage of potential energy; at the same time, since the oil in the rodless chamber of the driving oil cylinder is introduced into the oil tank through the electromagnetic reversing valve 1, the check valve 2 and the throttle valve 1, the return oil pressure is increased, so that part of the oil flows into the rod chamber of the driving oil cylinder first, and the flow regeneration is realized; at this time, the main pump does not provide oil, and the oil in the rod chamber of the driving oil cylinder all comes from the rodless chamber of the driving oil cylinder. When the pressure of the hydraulic accumulator is higher than the maximum working pressure, in order to ensure the service life of the hydraulic accumulator, the electromagnetic reversing valve 2 works in the left position, the electromagnetic reversing valve 4 works in the right position, and the hydraulic accumulator stops storing energy.

[0012] When the lifting device rises, the throttle valve 2 opens to the opening corresponding to the lifting device's rising speed, the valve port of the throttle valve 1 is closed, and the electromagnetic reversing valve 2 works in the right position, that is, the P port of the electromagnetic reversing valve 2 is connected to the A port. The electromagnetic reversing valve 1, the electromagnetic reversing valve 3 and the electromagnetic reversing valve 4 work in the left position, that is, the P port of the electromagnetic reversing valve 1 is connected to the B port, the T port is connected to the A port, the P port of the electromagnetic reversing valve 3 is connected to the B port, and the P port of the electromagnetic reversing valve 4 is connected to the A port. The oil stored in the hydraulic accumulator is introduced into the rodless chamber of the balancing oil cylinder through the electromagnetic reversing valve 4 and the electromagnetic reversing valve 2, and the oil in the rod chamber of the balancing oil cylinder is introduced into the oil tank through the electromagnetic reversing valve 3; at the same time, the oil output by the main pump is introduced into the rodless chamber of the driving oil cylinder through the one-way valve 1 and the electromagnetic reversing valve 1. The lifting device rises under the joint action of the main pump and the hydraulic accumulator, realizing the utilization of the potential energy of the lifting device. When the pressure of the hydraulic accumulator is lower than the minimum working pressure, in order to ensure the service life of the hydraulic accumulator, the electromagnetic reversing valve 2 works in the left position, the electromagnetic reversing valve 4 works in the right position, and the hydraulic accumulator stops discharging energy. Since the liquid energy provided by the hydraulic accumulator can balance part of the gravity of the lifting device, it can also be equivalent to the liquid energy provided by the main pump to balance another part of the gravity of the lifting device, reducing the output power of the main pump and improving energy utilization. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the structural principle of the present invention.

[0014] Figure 2 It is a schematic diagram of the structural principle of the descending process of the lifting device of the present invention.

[0015] Figure 3 It is a schematic diagram of the structural principle of the lifting device of the present invention during the ascending process.

[0016] In the figure: 1, electric motor; 2, main pump; 2a, main pump oil outlet; 3, oil tank; 4, relief valve 1; 4a, relief valve 1 oil inlet; 4b, relief valve 1 oil outlet; 5, check valve 1; 5a, check valve 1 oil inlet; 5b, check valve 1 oil outlet; 6, check valve 2; 6a, check valve 2 oil inlet; 6b, check valve 2 oil outlet; 7, throttle valve 1; 7a, throttle valve 1 oil inlet; 7b, throttle valve 1 oil outlet; 8, throttle valve 2; 8a, throttle valve 2 oil inlet; 8b, Oil outlet of throttle valve 2; 9, solenoid reversing valve 1; 10, driving cylinder; 10a, driving cylinder with rod chamber; 10b, driving cylinder without rod chamber; 11, balancing cylinder; 11a, balancing cylinder with rod chamber; 11b, balancing cylinder without rod chamber; 12, solenoid reversing valve 2; 13, solenoid reversing valve 3; 14, solenoid reversing valve 4; 15, overflow valve 2; 15a, overflow valve 2 oil inlet; 15b, overflow valve 2 oil outlet; 16, hydraulic accumulator; 16a, hydraulic accumulator oil inlet. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solution and advantages of the present invention clear and detailed, the present invention is further described below through the accompanying drawings. However, the drawings described herein are only used to explain the present invention and are not used to limit the scope of the present invention.

[0018] like Figure 1 As shown, a hydraulic potential energy recovery and utilization system comprises a driving cylinder (10), a flow regeneration unit and a balancing unit; the driving cylinder is used to drive a lifting device; the flow regeneration unit comprises an electric motor (1), a main pump (2), an oil tank (3), an overflow valve 1 (4), a check valve 1 (5), a check valve 2 (6), a throttle valve 1 (7), a throttle valve 2 (8), and an electromagnetic reversing valve 1 (9); the balancing unit comprises a balancing cylinder (11), an electromagnetic reversing valve 2 (12), an electromagnetic reversing valve 3 (13), an electromagnetic reversing valve 4 (14), an overflow valve 2 (15), and a hydraulic accumulator (16).

[0019] like Figure 1 As shown, the main pump (2) is coaxially connected to the motor (1), and the main pump (2) is driven by the motor (1) to provide the oil required by the system.

[0020] like Figure 1As shown, the main pump oil outlet (2a) is divided into two paths, the first path is connected to the oil inlet (4a) of the overflow valve 1, the second path is connected to the oil inlet (5a) of the check valve 1, and the oil outlet (4b) of the overflow valve 1 is connected to the oil tank (3); the check valve 1 oil outlet (5b) is divided into three paths, the first path is connected to the oil outlet (6b) of the check valve 2, the second path is connected to the oil inlet (7a) of the throttle valve 1, and the third path is connected to the P port of the electromagnetic reversing valve 1 (9). The oil outlet (7b) of the throttle valve 1 is connected to the oil tank (3); the A port of the electromagnetic reversing valve 1 (9) is connected to the rod chamber (10a) of the driving cylinder, the B port is connected to the rodless chamber (10b) of the driving cylinder, the T port is divided into two paths, the first path is connected to the oil inlet (6a) of the check valve 2, and the second path is connected to the oil inlet (8a) of the throttle valve 2; the oil outlet (8b) of the throttle valve 2 is connected to the oil tank (3), forming a flow regeneration unit oil circuit.

[0021] like Figure 1 As shown, the relief valve 1 (4) is used to control the pressure of the system.

[0022] like Figure 1 As shown, the rodless chamber (11b) of the balancing oil cylinder is connected to the P port of the electromagnetic reversing valve 2 (12), the A port of the electromagnetic reversing valve 2 (12) is connected to the P port of the electromagnetic reversing valve 4 (14), and the B port of the electromagnetic reversing valve 2 (12) is connected to the oil tank (3); the A port of the electromagnetic reversing valve 4 (14) is divided into two paths, the first path is connected to the oil inlet (16a) of the hydraulic accumulator, and the second path is connected to the oil inlet (15a) of the overflow valve 2; the oil outlet (15b) of the overflow valve 2 is connected to the oil tank (3); the rod chamber (11a) of the balancing oil cylinder is connected to the P port of the electromagnetic reversing valve 3 (13), the A port of the electromagnetic reversing valve 3 (13) is connected to the P port of the electromagnetic reversing valve 4 (14), and the B port of the electromagnetic reversing valve 3 (13) is connected to the oil tank (3), forming a balancing unit oil circuit, thereby realizing the recovery, storage and utilization of the potential energy of the lifting device.

[0023] like Figure 1 As shown, the overflow valve 2 (15) is used to control the maximum working pressure of the hydraulic accumulator (16).

[0024] like Figure 2As shown, when the lifting device descends, the throttle valve 1 (7) opens to an opening corresponding to the descending speed of the lifting device, the valve port of the throttle valve 2 (8) is closed, and the electromagnetic reversing valve 1 (9) and the electromagnetic reversing valve 2 (12) work in the right position, that is, the P port of the electromagnetic reversing valve 1 (9) is connected to the A port, the T port is connected to the B port, and the P port of the electromagnetic reversing valve 2 (12) is connected to the A port. The electromagnetic reversing valve 3 (13) and the electromagnetic reversing valve 4 (14) work in the left position, that is, the P port of the electromagnetic reversing valve 3 (13) is connected to the B port, and the P port of the electromagnetic reversing valve 4 (14) is connected to the A port. The oil in the rodless chamber (11b) of the balancing oil cylinder is introduced into the hydraulic accumulator (16) through the electromagnetic reversing valve 2 (12) and the electromagnetic reversing valve 4 (14), thereby realizing the recovery and storage of potential energy. At the same time, since the oil in the rodless chamber (10b) of the driving oil cylinder is introduced into the oil tank (3) through the electromagnetic reversing valve 1 (9), the check valve 2 (6) and the throttle valve 1 (7), the return oil pressure is increased, so that part of the oil flows preferentially into the rod chamber (10a) of the driving oil cylinder, thereby realizing flow regeneration. At this time, the main pump does not provide oil, and the oil in the rod chamber (10a) of the driving oil cylinder all comes from the rodless chamber (10b) of the driving oil cylinder. When the pressure of the hydraulic accumulator (16) is higher than the maximum working pressure, in order to ensure the service life of the hydraulic accumulator (16), the electromagnetic reversing valve 2 (12) works in the left position, the electromagnetic reversing valve 4 (14) works in the right position, and the hydraulic accumulator (16) stops storing energy.

[0025] like Figure 3As shown, when the lifting device rises, the throttle valve 2 (8) opens to an opening corresponding to the lifting speed of the lifting device, the valve port of the throttle valve 1 (7) is closed, and the electromagnetic reversing valve 2 (12) works in the right position, that is, the P port of the electromagnetic reversing valve 2 (12) is connected to the A port. The electromagnetic reversing valve 1 (9), the electromagnetic reversing valve 3 (13) and the electromagnetic reversing valve 4 (14) work in the left position, that is, the P port of the electromagnetic reversing valve 1 (9) is connected to the B port, the T port is connected to the A port, the P port of the electromagnetic reversing valve 3 (13) is connected to the B port, and the P port of the electromagnetic reversing valve 4 (14) is connected to the A port. The oil stored in the hydraulic accumulator (16) is introduced into the rodless chamber (11b) of the balancing oil cylinder through the electromagnetic reversing valve 4 (14) and the electromagnetic reversing valve 2 (12), and the oil in the rod chamber (11a) of the balancing oil cylinder is introduced into the oil tank (3) through the electromagnetic reversing valve 3 (13); at the same time, the oil output by the main pump (2) is introduced into the rodless chamber (10b) of the driving oil cylinder through the check valve 1 (5) and the electromagnetic reversing valve 1 (9), and the lifting device rises under the joint action of the main pump (2) and the hydraulic accumulator (16), realizing the utilization of the potential energy of the lifting device. When the pressure of the hydraulic accumulator (16) is lower than the minimum working pressure, in order to ensure the service life of the hydraulic accumulator (16), the electromagnetic reversing valve 2 (12) works in the left position, the electromagnetic reversing valve 4 (14) works in the right position, and the hydraulic accumulator (16) stops discharging energy. Since the liquid energy provided by the hydraulic accumulator (16) can balance part of the gravity of the lifting device, it can also be equivalent to the liquid energy provided by the main pump (2) to balance another part of the gravity of the lifting device, thereby reducing the output power of the main pump (2) and improving energy utilization.

[0026] The beneficial effects of the present invention are: the lifting device of the present invention can effectively solve the problem of potential energy recovery and utilization using two different oil circuits and the main pump still needs to provide oil when the lifting device descends. There are fewer energy conversion links and the energy utilization rate is high. The present invention can be widely used in various lifting devices driven by hydraulic cylinders.

[0027] The above description is only a preferred specific implementation mode of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are included in the patent protection scope of the present invention.

Claims

1. A hydraulic potential energy recovery and utilization system, characterized in that: It comprises a driving cylinder (10), a flow regeneration unit and a balancing unit; the driving cylinder is used to drive a lifting device; the flow regeneration unit comprises an electric motor (1), a main pump (2), an oil tank (3), an overflow valve 1 (4), a check valve 1 (5), a check valve 2 (6), a throttle valve 1 (7), a throttle valve 2 (8), and an electromagnetic reversing valve 1 (9); the balancing unit comprises a balancing cylinder (11), an electromagnetic reversing valve 2 (12), an electromagnetic reversing valve 3 (13), an electromagnetic reversing valve 4 (14), an overflow valve 2 (15), and a hydraulic accumulator (16); The main pump (2) is coaxially connected to the motor (1), and the main pump (2) is driven by the motor (1); the main pump oil outlet (2a) is divided into two paths, the first path is connected to the oil inlet (4a) of the overflow valve 1, the second path is connected to the oil inlet (5a) of the check valve 1, and the oil outlet (4b) of the overflow valve 1 is connected to the oil tank (3); the check valve 1 oil outlet (5b) is divided into three paths, the first path is connected to the oil outlet (6b) of the check valve 2, the second path is connected to the oil inlet (7a) of the throttle valve 1 The first path is connected to the oil inlet (6a) of the one-way valve 2, and the second path is connected to the oil inlet (8a) of the throttle valve 2; the oil outlet (7b) of the throttle valve 1 is connected to the oil tank (3); the A port of the solenoid reversing valve 1 (9) is connected to the rod chamber (10a) of the driving cylinder, the B port is connected to the rodless chamber (10b) of the driving cylinder, and the T port is divided into two paths, the first path is connected to the oil inlet (6a) of the one-way valve 2, and the second path is connected to the oil inlet (8a) of the throttle valve 2; the oil outlet (8b) of the throttle valve 2 is connected to the oil tank (3), forming a flow regeneration unit oil circuit; The rodless chamber (11b) of the balancing oil cylinder is connected to the P port of the electromagnetic reversing valve 2 (12), the A port of the electromagnetic reversing valve 2 (12) is connected to the P port of the electromagnetic reversing valve 4 (14), and the B port of the electromagnetic reversing valve 2 (12) is connected to the oil tank (3); the A port of the electromagnetic reversing valve 4 (14) is divided into two paths, the first path is connected to the oil inlet (16a) of the hydraulic accumulator, and the second path is connected to the oil inlet (15a) of the overflow valve 2; the oil outlet (15b) of the overflow valve 2 is connected to the oil tank (3); the rod chamber (11a) of the balancing oil cylinder is connected to the P port of the electromagnetic reversing valve 3 (13), the A port of the electromagnetic reversing valve 3 (13) is connected to the P port of the electromagnetic reversing valve 4 (14), and the B port of the electromagnetic reversing valve 3 (13) is connected to the oil tank (3), forming a balancing unit oil circuit to realize the recovery, storage and utilization of the potential energy of the lifting device; The hydraulic accumulator (16) is used to store high-pressure oil in the rodless chamber (11b) of the balancing oil cylinder; The overflow valve 2 (15) is used to control the maximum working pressure of the hydraulic accumulator (16).

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