WO2021093300A1 - Energy-saving control system and control method for excavator boom - Google Patents

Abstract

Disclosed are an energy-saving control system and control method for an excavator boom. Said system comprises a boom hydraulic system and a boom potential energy recycling device; the boom potential energy recycling device comprises a potential energy recycling reversing valve, a dual fluid source coupler and an energy accumulator; the boom hydraulic system comprises two boom operating assemblies and two main pumps corresponding to the two boom operating assemblies; a first pressure sensor and a second pressure sensor are respectively provided on pilot hydraulic lines for controlling the boom operating assemblies to switch between boom lowering and boom raising, and a shut-off valve is provided on the hydraulic line of one of the boom operating assemblies, the first pressure sensor is in feedback connection with a displacement control mechanism of the main pump and an energy recovery position switching module of the potential energy recycling reversing valve, and the second pressure sensor is in feedback connection with the shut-off valve and an energy release position switching module of the potential energy recycling reversing valve. The present invention has high reliability and good operation coordination, and recovers the boom potential energy efficiently, achieving the engineering implementation of boom energy recycle technology.

Description

Energy-saving control system and control method for excavating mobile arm Technical field

The invention belongs to the energy-saving technology of excavators, and specifically relates to an energy-saving control system and a control method of an excavating mobile arm.

Background technique

In the context of global environmental pollution and energy shortages, governments, industries and markets have put forward higher requirements for the energy consumption and emissions of large-scale machinery and equipment, and energy-saving and emission-reduction technologies have become a research hotspot in the field of construction machinery and equipment. Excavator is a kind of commonly used construction machinery. The excavating arm often uses hydraulic oil to act on the cylinder to achieve its lifting. Because the mass of the arm and the stick and bucket acting on it are large, it is mainly used as an excavator. The external potential device (the “potential device” referred to here refers to the change of potential energy during the operation of the device). In order to prevent the boom device from being prone to weightlessness during the descent process, the previous solution was to There is a throttling device on the return pipeline of the large cavity of the oil cylinder to generate adjustable back pressure for speed control, so most of the energy of the boom device is converted into heat energy, which is wasted in vain, and in order to prevent the temperature of the hydraulic oil from being drastically The damage to the system caused by the increase requires a heat dissipation device, which further increases the cost of the equipment.

In order to improve the energy utilization rate of excavators and make full use of the mature reliability of the excavator platform, most manufacturers develop energy recovery and utilization devices based on the original excavator platform, but how to improve the efficiency of energy recovery and utilization devices, and Ensuring that the new system reliability of the energy recovery and utilization device is compatible with the operation of the existing operating system of the excavator is the difficulty in the engineering implementation of the excavator to improve the energy-saving technology through energy recovery and utilization.

technical problem

The technical problem solved by the present invention is to provide an energy-saving control system and a control method for an excavating maneuverable arm in view of the technical problems of the existing energy recovery and utilization device and the hydraulic system of the excavator to realize the engineering implementation of energy-saving technology.

Technical solutions

The present invention adopts the following technical solutions to achieve.

An energy-saving control system for an excavating boom includes a boom hydraulic system and a boom potential energy recovery and utilization device.

The boom potential energy recovery and utilization device includes a potential energy recovery and utilization reversing valve, a dual oil source coupler and an accumulator.

The potential energy recovery and utilization reversing valve includes a neutral position, an energy release position and an energy recovery position.

The potential energy recovery and utilization reversing valve is located in the middle position, and the inlet and outlet oil passages of the boom hydraulic system and the two oil chambers of the boom cylinder are directly connected into a loop through the neutral function of the potential energy recovery and utilization reversing valve.

The potential energy recovery and utilization reversing valve is located in the energy recovery position, and the two oil chambers of the boom cylinder are in differential communication through the potential energy recovery and utilization reversing valve, and are connected to the accumulator and the boom hydraulic system at the same time. Oil way.

The potential energy recovery and utilization reversing valve is located at the energy release position, one of the oil chambers of the boom cylinder is connected to the return path of the boom hydraulic system through the potential energy recovery and utilization reversing valve, and the other oil cavity of the boom cylinder passes through the double The oil source coupler is respectively connected to the oil inlet and the accumulator of the boom hydraulic system.

The boom hydraulic system includes two sets of boom operation linkages in the excavator multi-way reversing valve and two sets of main pumps corresponding to the two sets of boom operation linkages. The boom operation linkage is controlled to switch boom lowering and moving. A first pressure sensor and a second pressure sensor are respectively provided on the pilot oil path of the boom lift, and a shut-off valve is provided on the pilot oil path of a group of boom operation linkages, wherein the first pressure sensor is connected to the discharge of the main pump. The quantity control mechanism and the energy recovery position switching module of the potential energy recovery and utilization reversing valve are feedback connected, and the second pressure sensor is feedback connected with the cut-off valve and the energy release position switching module of the potential energy recovery and utilization reversing valve.

Further, the potential energy recovery and utilization reversing valve is a three-position seven-way electro-hydraulic reversing valve. The electromagnet corresponding to the energy recovery position and the electromagnet corresponding to the energy release position respectively feed back to the first pressure sensor and the second pressure sensor. Connected, the potential energy recovery and utilization reversing valve has an oil inlet, an oil return port, two groups of working oil ports, and three groups of energy-saving oil ports. The oil inlet, the oil return port and the two groups of working oil ports are respectively connected to the boom The two oil ports of the oil cylinder and the inlet and outlet oil circuits of the hydraulic system, one group of energy-saving oil ports is connected to the accumulator, and the other two groups of energy-saving oil ports are connected to the dual oil source coupler, which are connected in parallel To one of the oil chambers of the boom cylinder, and an energy release check valve is arranged on the parallel oil path of the dual oil source coupler and the boom cylinder.

The potential energy recovery and utilization reversing valve is in the middle position, and the two oil chambers of the boom cylinder and the inlet and outlet oil passages of the hydraulic system pass through the potential energy recovery and utilization reversing valve's oil inlet, oil return port and two sets of work The oil ports are connected to form a circuit, and the three groups of energy-saving oil ports are separately blocked.

The potential energy recovery and utilization reversing valve is located at the energy recovery position, and the two oil chambers of the boom cylinder are in differential communication through the two sets of working oil ports of the potential energy recovery and utilization reversing valve. They are respectively connected to the energy-saving oil port connected to the accumulator and the oil inlet connected to the oil inlet of the hydraulic system, and the oil return port and the two groups of energy-saving oil ports connected to the dual oil source coupler are respectively blocked.

The potential energy recovery and utilization reversing valve is located at the energy release position. One of the oil chambers of the boom cylinder is connected to the oil return path of the hydraulic system through one of the group of working oil ports and the oil inlet, and the other group of working oil ports is cut off and returns to The oil ports are connected to one group of energy-saving oil ports connected to the dual oil source coupler, and the other oil cavity of the boom cylinder is respectively connected to the oil inlet path and the accumulator of the hydraulic system through the dual oil source coupler.

Further, in the energy recovery position of the potential energy recovery and utilization reversing valve, a differential one-way valve is provided to connect the working oil ports of the two oil chambers of the boom cylinder to realize one-way differential communication.

In a preferred solution of the present invention, the dual oil source coupler is a dual-cylinder coupler, including a first cylinder and a second cylinder arranged in parallel, and the first cylinder and the piston inside the second cylinder are synchronously connected, so The internal oil chambers of the first cylinder and the second cylinder are respectively connected to the two sets of energy-saving oil ports of the potential energy recovery and utilization reversing valve, which serve as the oil inlet end of the dual oil source coupler, and the other of the first cylinder or the second cylinder The oil chamber is connected in parallel to one of the oil chambers of the boom cylinder through the output end, and the output end of the dual oil source coupler is connected to the oil tank through a one-way oil inlet.

Further, a return spring for returning the piston is provided inside the double-cylinder coupler.

In another preferred solution, the dual oil source coupler is a dual motor coupler, including two sets of coupled motors arranged in parallel, and the input ends of the two sets of coupled motors are respectively connected to the two sets of energy-saving reversing valves of potential energy recovery and utilization. Oil port, the output ends of the two groups of coupling motors are connected in parallel and then connected in parallel to one of the oil chambers of the boom cylinder.

Further, the displacement control mechanism of the main pump includes a signal or valve arranged between the displacement negative control port, the pilot oil path of the multi-way reversing valve, and the pilot oil source of the boom operating link, and the signal Or a proportional pressure reducing valve between the pilot oil source connected to the valve and the boom operation, and the electromagnet of the proportional pressure reducing valve is feedback-connected to the first pressure sensor.

Further, the cut-off valve is a two-position cut-off reversing valve arranged on the pilot oil circuit of the boom operating link, and the electromagnet of the two-position cut-off reversing valve is feedback connected to the second pressure sensor.

In the energy-saving control system of an excavating arm of the present invention, it further includes a controller and a working mode switching signal transmitter that are connected in communication, and the controller is connected to the first pressure sensor, the second pressure sensor, and the main pump. The energy recovery position switching module of the quantity control mechanism, the shut-off valve, and the potential energy recovery and utilization reversing valve is in communication connection with the energy release module.

The invention also discloses a control method adopting the energy-saving control system of the excavating arm, which includes a conventional control mode and an energy-saving control mode.

In the normal control mode, the signal of the normal control mode is given to the controller through the working mode switching signal transmitter. The controller does not monitor the first pressure sensor and the second pressure sensor, and the potential energy recovery and utilization reversing valve is in the middle In the normal position, the displacement control mechanism of the main pump and the shut-off valve are in the normal position, and the boom cylinder is conventionally controlled by the boom hydraulic system.

In the energy-saving control mode, the signal of the energy-saving operating mode is sent to the controller through the signal transmitter of operating mode switching, and the controller continuously detects the signals of the first pressure sensor and the second pressure sensor.

among them.

When the controller detects the pressure signal sent by the first pressure sensor, the boom of the excavator is in a descending action at this time, and the controller controls the displacement control mechanism of the main pump to reduce the main pump to the boom cylinder pump The displacement of the hydraulic oil is sent, and the controller controls the potential energy recovery and utilization reversing valve to be in the energy recovery position, and the pressure oil converted by the potential energy of the boom descending is recovered by the boom potential energy recovery and utilization device.

When the controller detects the pressure signal sent by the second pressure sensor, the boom of the excavator is in a lifting action at this time, and the controller controls the shut-off valve to be energized, so that the boom operation corresponding to the shut-off valve is linked Stop supplying oil to the boom cylinder, a set of main pumps of the boom hydraulic system and the boom operation are combined to supply oil to the boom cylinder, and the controller controls the potential energy recovery and utilization reversing valve to be in the energy release position. The oil supply of the hydraulic system, together with the pressure oil recovered by the boom potential energy recovery and utilization device, supplies oil to the boom cylinder.

Beneficial effect

The present invention has the following beneficial effects.

The invention adopts a newly designed boom potential energy recovery and utilization device and is combined with a boom hydraulic system. The boom potential energy recovery and utilization device changes the in and out of the boom cylinder of the external potential device through a three-position seven-way electro-hydraulic directional valve. Through the differentially interconnected regenerative energy recovery method of the two oil chambers of the boom cylinder, the potential energy changed during the boom descent process is efficiently recovered, avoiding the use of pumps and motors with lower energy-saving efficiency, and reducing the main pump Output flow or omit a main pump in the dual main pump system to participate in the work, which reduces the energy output of the engine, reduces fuel consumption and exhaust emissions; through dual oil source couplers and accumulators, the recovered hydraulic energy and hydraulic pressure The hydraulic energy provided by the main pump once again drives the boom cylinder to overcome the gravitational potential energy to perform a lifting action, the recovered energy is released more smoothly, and the reliability of the boom is improved.

The combination of the boom potential energy recovery and utilization device of the present invention and the boom hydraulic system makes it possible to implement the energy-saving control engineering implementation of the excavator, without the need to redesign the existing excavating boom hydraulic system, which corresponds to the control adopted by the control system The method proposes two working modes, namely the conventional control mode and the energy-saving control mode. In the energy-saving control mode, when the boom is lowered, the associated main pump is controlled to reduce the displacement to prevent the main pump from outputting excessively when the potential energy of the boom is recovered. Too much energy is wasted. In the energy-saving control mode, when the boom is lifted, the dual-pump combined fuel supply mode in the conventional mode is released, and one of the pumps is involved in the work, and the recovered potential energy is used for combined fuel supply, thereby reducing engine energy output and saving energy. When there is a problem with the energy-saving component of the boom potential energy recycling device in the energy-saving control mode, it can be switched to work in the normal mode to ensure the working reliability of the equipment.

In summary, the energy-saving control system for excavating boom provided by the present invention has higher reliability and operation coordination, and the boom potential energy recovery and utilization device adopted by it is highly efficient, and combined with the boom hydraulic system to realize the operation Engineering implementation of arm energy recovery and utilization technology.

The present invention will be further described below in conjunction with the drawings and specific embodiments.

Description of the drawings

Fig. 1 is a hydraulic schematic diagram of the energy-saving control system of the excavating arm in the embodiment.

Fig. 2 is a hydraulic schematic diagram of the boom potential energy recovery and utilization device in Fig. 1.

Fig. 3 is a schematic diagram of a structure of the dual oil source coupler in the embodiment.

Figure 4 is a schematic diagram of another structure of the dual oil source coupler in the embodiment.

Fig. 5 is another hydraulic schematic diagram of the energy-saving control system of the excavating boom in the embodiment.

Numbers in the figure: 1-boom, 2-boom cylinder, 31-first main pump, 32-second main pump, 4-multi-way reversing valve, 41-first boom operating link, 42-second Boom operation linkage, 5-pilot oil source, 51-boom lift pilot operation valve, 52-boom down pilot operation valve, 6-boom potential energy recovery and utilization device, 61-potential energy recovery and utilization reversing valve, 62- Dual oil source coupler, 621-first cylinder, 622-second cylinder, 623-piston, 624-oil inlet, 625-return spring, 626-first coupling pump, 627-second coupling pump, 63- Energy release check valve, 64-accumulator, 71-first pressure sensor, 72-second pressure sensor, 73-controller, 74-operating mode switching signal transmitter, 81-signal or valve, 82-proportional Pressure reducing valve, 83-stop reversing valve.

The best mode of the present invention

Type here a paragraph describing the best embodiment of the present invention.

Embodiments of the present invention

Examples.

Referring to Figure 1, the figure shows a hydraulic principle diagram of an energy-saving control system for an excavating boom. The control system is a specific embodiment of the present invention, and specifically includes a boom hydraulic system and a boom potential energy recovery and utilization device. The boom hydraulic system is a conventional system for hydraulic control of the existing excavating boom. The boom hydraulic system in the figure includes the excavator multi-way reversing valve 4, which includes two links corresponding to the control boom Action boom operating link: the first boom operating link 41 and the second boom operating link 42 (the operating link referred to here refers to one of the multi-way reversing valves stacked in the multi-way valve, including The reversing valve and its corresponding pilot control oil circuit part), the first boom operating link 41 and the second boom operating link 42 respectively correspond to the first main pump 31 and the second main pump 32, and are jointly supplied by the dual main pumps. The boom cylinder 2 that drives the boom 1 is supplied with oil.

In the boom hydraulic system, the first boom operating link 41 and the second boom operating link 42 are correspondingly provided with the same set of pilot control oil circuits, including the pilot oil source 5 and the pilot oil source 5 connecting and controlling two sets of boom operations The pilot oil circuit that switches to the boom raising position or the boom lowering position is connected. The two sets of pilot oil circuits are respectively equipped with a boom raising pilot operation valve 51 that controls the boom raising and a boom lowering control that controls the boom. Pilot operated valve 52. The specific pilot oil circuit arrangement of the boom operating link is a conventional technology in the existing excavator, and the internal oil circuit of the boom operating link is not described in detail in this embodiment.

The following first describes in detail the conventional control process of boom raising and boom lowering of the excavator.

When the boom lift pilot operation valve 51 is operated, the boom lift pilot operation valve 51 outputs pilot pressure oil while pushing the first boom operation link 41 and the second boom operation link 42 of the multi-way directional control valve 4 to reverse direction Enter the boom lift position. At this time, the first main pump 31 and the second main pump 32 are combined through the first boom operating link 41 and the second boom operating link 24 to supply oil to the rodless cavity of the boom cylinder 2 When the boom is lifted, the speed of boom lift is determined by the operation opening degree of the displacement control mechanism of the first main pump 31 and the second main pump 32. If the operation opening degree is large, the first main pump 31 and the second main pump 31 The output flow of the main pump 32 is large, and the boom lifts quickly; when the boom down pilot operating valve 52 is operated, the boom down pilot operating valve 52 outputs pilot pressure oil to push the second boom operating link of the multi-way directional valve 4 42 reversing into the boom lowering position. At this time, the second main pump 32 supplies oil to the rod cavity of the boom cylinder 2 through the second boom operating link 42 to lower the boom, and the back pressure of the boom is lowered by the second The lowering position orifice of the boom operating link 42 is generated. Similarly, the speed of boom lowering is determined by the operating opening of the boom lowering pilot operating valve. If the operating opening is large, the output flow of the second main pump 32 will be large. The arm descends quickly.

In this embodiment, a boom potential energy recovery and utilization device 6 is added to the existing conventional excavating boom hydraulic system. The boom potential energy recovery and utilization device 6 includes a potential energy recovery and utilization reversing valve 61, a dual oil source coupler 62 and an accumulator.能器64..

Among them, the potential energy recovery and utilization reversing valve 61 is a three-position reversing valve, including a neutral position, an energy release position and an energy recovery position. When the potential energy recovery and utilization reversing valve 61 is in the neutral position, the multi-way switching valve of the slave arm hydraulic system The inlet and outlet oil passages leading to the valve and the rod and rodless chambers of the boom cylinder 2 are directly connected into a loop through the potential energy recovery and utilization of the neutral function of the reversing valve 61. At this time, the normal operation of the boom cylinder 2 is ensured, and the energy is not correct. Recycling.

When the potential energy recovery and utilization reversing valve 61 is located in the energy recovery position, the rod cavity and the rodless cavity of the boom cylinder 2 are in differential communication through the potential energy recovery and utilization reversing valve 61, and are connected to the accumulator 64 and the boom hydraulic pressure at the same time. The oil inlet of the system.

When the potential energy recovery and utilization reversing valve 61 is in the energy release position, the rod cavity of the boom cylinder 2 is connected to the return path of the boom hydraulic system through the potential energy recovery reversing valve 61, and the rodless cavity of the boom cylinder 2 passes through the double oil The source coupler 62 is respectively connected to the oil inlet of the boom hydraulic system and the accumulator 64.

In order to realize automatic control between the potential energy recovery and utilization device 6 and the original excavating boom hydraulic system, this embodiment is provided with a pilot oil path on the boom hydraulic system that controls the boom operation linkage to switch boom down and boom up. A pressure sensor 71 and a second pressure sensor 72, and a cut-off reversing valve 83 is provided on the pilot oil path of the first boom operating link 41, wherein the first pressure sensor 71 and the displacement control mechanism of the second main pump and The energy recovery position switching module of the potential energy recovery and utilization reversing valve 61 is feedback connected, and the second pressure sensor 72 is feedback connected to the cut-off reversing valve 83 and the energy release position switching module of the potential energy recovery and utilization reversing valve.

Specifically, the displacement control mechanism of the main pump includes a signal or valve 81 provided between the negative displacement control port, the pilot oil path PS2 port of the multi-way reversing valve, and the pilot oil source 5 of the boom operating link, and A proportional pressure reducing valve 82 is provided between the signal or valve 81 and the pilot oil source 5 connected to the boom operation. The signal or valve 81 adopts a shuttle valve, and the proportional pressure reducing valve 82 adopts an electric proportional pressure reducing valve. The electromagnet is feedback connected to the first pressure sensor 71.

The cut-off reversing valve 83 is a two-position cut-off reversing valve set on the pilot oil path of the first boom operating link 41, and the cut-off reversing valve 83 can be set on the boom lowering pilot oil path of the first boom operating link 41 , The cut-off reversing valve 83 is energized to connect the pilot oil circuit of the boom down position, and the pressure at both ends of the first boom operating link 41 is balanced without reversing, as shown in Figure 1, it can also be set in the first boom operating link 41's boom lift pilot operation link boom lift pilot oil circuit, the cut-off reversing valve 83 is energized to cut off the boom lift pilot oil circuit, the first boom operation link 41 does not change direction, as shown in Figure 5 As shown, the electromagnet of the shut-off reversing valve 83 is feedback connected to the second pressure sensor 72.

With reference to Figure 2, the potential energy recovery and utilization reversing valve 61 in this embodiment is specifically a three-position seven-port electro-hydraulic reversing valve, wherein the three-position seven-port electro-hydraulic reversing valve is provided in the boom cylinder 2 and the boom hydraulic system. Between the inlet and outlet oil paths of the reversing valve 4, it is used to realize the normal operation, energy recovery and energy release of the boom cylinder 2. The dual oil source coupler 62 uses the reversing valve 61 and the potential energy recovery through the oil path. The inlet and outlet oil circuits of the boom cylinder 2 are arranged in parallel for coupling and summarizing the active hydraulic energy of the boom hydraulic system 3 and the recovered hydraulic energy during the energy release process. The accumulator 64 and the potential energy recovery and utilization reversing valve 61 pass through The oil circuit is used to recover, store and release hydraulic energy.

Among them, the potential energy recovery and utilization reversing valve 61 of this embodiment includes a neutral position, an energy release position, and an energy recovery position. Each position is provided with an oil inlet C, an oil return port D, a working oil port E, and a working oil port. F. Energy-saving oil port G, energy-saving oil port H and energy-saving oil port I, among which, oil inlet C and oil return port D are connected to oil inlet A and oil outlet B of multi-way directional valve 4, and working oil port E And working oil port F are respectively connected to the boom cylinder 2 corresponding to the two oil ports with rod cavity and rodless cavity, energy-saving oil port I is connected to accumulator 64, energy-saving oil port G and energy-saving oil port H are respectively connected to the double The two input ends of the oil source coupler 62, the output end of the dual oil source coupler 62 are connected in parallel with the working oil port connected to the inlet and outlet oil circuits of the rodless cavity of the boom cylinder 2, and the dual oil source coupler 62 is connected to the drive An energy release check valve 63 is arranged on the parallel oil circuit of the oil cylinder to prevent the oil in the oil circuit of the boom oil cylinder in the normal mode from flowing back into the dual oil source coupler.

The specific functions inside the reversing valve 61 for this potential energy recovery and utilization are as follows.

When the potential energy recovery and utilization reversing valve 61 is in the neutral position, the two oil ports of the boom cylinder 2 with a rod cavity and a rodless cavity and the in and out oil passages A and B of the boom hydraulic system 3 are switched by potential energy recovery and utilization. The oil inlet C, the oil return port D and the two groups of working oil ports E and F of the valve 61 are directly connected to form a circuit. The other three groups of energy-saving oil ports G, H, I are cut off respectively, and the boom cylinder 2 passes through the boom hydraulic system In the normal mode driving of lifting and lowering actions, the boom cylinder 2 does not have an energy recovery function at this time.

When the switching potential energy recovery and utilization reversing valve 61 is switched to the energy recovery position, the boom cylinder 2 drives the boom 1 down to collect the gravitational potential energy. The two oil ports of the boom cylinder 2 with a rod cavity and a rodless cavity are differentially connected through the two sets of working oil ports E and F of the directional valve 61 through the potential energy recovery and utilization, and the working oil ports E and F are also connected to and connected respectively The energy-saving oil port I of the accumulator 64 is connected to the oil inlet C connected to the oil inlet of the hydraulic system, and the oil return port D and the energy-saving oil ports G and H connected to the dual oil source coupler 62 are respectively cut off. The boom hydraulic The system 3 provides hydraulic oil with a smaller displacement into the rod cavity of the boom cylinder 2. The boom cylinder 2 returns most of the oil in the rodless cavity to the accumulator 64 under the action of the gravity potential energy of the boom. Internal storage pressure, a small part of the oil differentially returns to the inside of the rod cavity of the boom cylinder 2. In the energy recovery position of the potential energy recovery and utilization reversing valve 61, setting a differential one-way valve will make the energy recovery process The hydraulic oil can only circulate in one direction from the working port F connected to the rod-less cavity to the working port E connected to the rod cavity to achieve one-way differential communication and maintain the stability and reliability of the boom descent process. At this time, the dual oil sources are coupled The device 62 has no effect.

When the switching potential energy recovery and utilization reversing valve 61 is switched to the energy release position, the pressure collected by the accumulator 64 enters the boom cylinder 2 to drive the boom 1 upward, and the rod cavity oil port of the boom cylinder 2 passes through the work The oil port E and the oil inlet C on the potential energy recovery and utilization reversing valve 61 are connected to the oil return path of the boom hydraulic system 3, and the boom cylinder is realized through the rodless cavity of the boom cylinder 2 and the oil return with the rod cavity. 2 action, the working oil port F connected to the rodless cavity oil port of the boom cylinder 2 is cut off, the potential energy recovery uses the oil return port D of the reversing valve 61 to switch to the oil inlet of the boom hydraulic system 3, and at the same time the potential energy The inside of the reversing valve 61 is recycled and the oil return port D is connected to a group of energy-saving oil ports G connected to the dual oil source coupler 62. The oil inlet of the multi-way reversing valve of the boom hydraulic system passes through the dual oil source coupler 62 Into the rodless cavity, at the same time, the other energy-saving oil port H connected to the dual oil source coupler 62 is connected to the other energy-saving oil port I connected to the accumulator 64, and the pressure oil stored in the accumulator 64 passes through the dual oil source The coupler is coupled with the oil inlet of the multi-way reversing valve of the boom hydraulic system and enters the rodless cavity of the boom cylinder 2 to drive the boom to lift, and the boom is driven to lift again by the previously recovered boom down potential energy. The addition of the recovered energy in the accumulator 64 can reduce the displacement of the boom hydraulic system 3 during the boom lifting process, and ultimately achieve the effect of energy saving.

The potential energy recovery and utilization reversing valve 61 adopts electronic control. When the DT3 and DT4 solenoid valves of the potential energy recovery and utilization reversing valve 61 are not energized, they are in the neutral position, between the oil return port D and the working oil port F, and the oil inlet C Connect with working oil port E. The middle position is used to connect the conventional oil circuit of boom cylinder 2 and boom hydraulic system 3 in non-energy-saving mode. The boom hydraulic system 3 drives the boom cylinder 2 to operate normally; potential energy recovery When the DT3 solenoid valve of the reversing valve 61 is energized, it enters the energy release position. The energy-saving oil port I and the energy-saving oil port H, the oil return port D and the energy-saving oil port G, and the oil inlet C and the working oil port E are respectively connected. The rod cavity of the boom cylinder 2 returns oil through the oil inlet C and the working oil port E and the boom hydraulic system 3. The oil output from the accumulator 64 and the hydraulic main pump passes through the energy-saving oil port I and energy-saving oil respectively The connecting passage of port H, the connecting passage of oil return port D and energy-saving oil port G enter the dual oil source coupler 62 to merge, and then through the energy release check valve 63 into the rodless cavity of the boom cylinder 2 to lift together The boom does work; the potential energy recovery and utilization of the DT4 solenoid valve of the reversing valve 61 enters the energy recovery position when it is energized. The energy-saving oil port I and the working oil port F, and the oil inlet C and the working oil port E are respectively connected, hydraulic The main pump supplies oil from the oil inlet C and working oil port E to the rod cavity of the boom cylinder 2 through the boom hydraulic system 3. The oil between the energy-saving oil port I and the working oil port F can pass through the internal check valve Enter the oil inlet C and the working oil port E, and vice versa. Therefore, the differential connection of the boom cylinder is realized. The effective area of balancing the boom load is changed from the internal piston area of the boom cylinder 2 to the end area of the piston rod. The area is reduced by about half, and the back pressure of the balanced boom is nearly doubled. Except for part of the oil in the rodless cavity of the boom cylinder returns to the rod cavity, the rest of the oil enters the accumulator 64 through the energy-saving oil port I. Boost energy recovery. The use of the regenerative energy pressurization recovery method in which the rod cavity and the rodless cavity of the boom cylinder 2 are interconnected avoids the energy recovery of pumps and motors with low energy saving efficiency. The dual oil source coupler is used to match the hydraulic main pump in parallel, and the pump is used With the energy recovery of the energy storage device, the energy utilization rate can reach more than 85%.

As shown in FIGS. 3 and 4, the dual oil source coupler 62 of this embodiment can adopt a dual hydraulic cylinder structure and a dual motor structure.

As shown in FIG. 3, the dual oil source coupler 62 of the dual-cylinder structure includes a first cylinder 621 and a second cylinder 622 arranged in parallel. The first cylinder 621 and the second cylinder 622 are respectively provided with input terminals IN1 and IN2, and the first cylinder 621 is synchronously connected with the piston 623 inside the second cylinder 622. The piston inside the first cylinder 621 separates the inside into a rod cavity and a rodless cavity. The rod with the rod cavity extends to be integrated with the piston inside the second cylinder 622 Connected, the piston inside the second cylinder 622 is smaller than the inner diameter of the cylinder barrel, connecting the rod cavity and the rodless cavity inside the second cylinder 622. The rod cavity of the first cylinder 621 and the rodless cavity of the second cylinder 622 pass through IN1 and IN2 is connected to the two groups of energy-saving oil ports of the potential energy recovery and utilization reversing valve 61 as the oil inlet end of the dual oil source coupler. The other oil chamber of the first cylinder 621 is connected in parallel to one of the boom cylinders through the output end OUT At the same time, the oil cavity is connected to the oil tank through a one-way oil inlet 624. The pressure oil inside the accumulator 64 enters the rodless cavity of the second cylinder 622 through IN2, and the main hydraulic pump 4 is provided by the boom hydraulic system 3. The hydraulic oil enters the rod cavity of the first cylinder 621 through IN1, and the two together push the piston 623 to squeeze the hydraulic oil inside the rodless cavity of the first cylinder 621, and pressurize the oil through the output port OUT of the first cylinder 621 Output to the boom cylinder 2 to realize the coupling effect of the accumulator 64 and the dual oil source provided by the boom hydraulic system. The first cylinder 621 is provided with a return spring for the piston 623 to return to the rodless cavity where the output end is located. 625. After the boom is lifted, the return spring 625 pushes the piston 623 back, and the hydraulic oil sucked into the oil tank through the one-way oil inlet 624 is filled into the rodless cavity in the first cylinder 621.

As shown in FIG. 3b, the dual oil source coupler 62 of the dual motor structure includes a first coupled motor 626 and a second coupled motor 627 arranged in parallel, wherein the input terminal IN1 of the first coupled motor 626 and the input of the second coupled motor 627 are The terminals IN2 are respectively connected to the two groups of energy-saving oil ports G and H of the potential energy recovery and utilization reversing valve 61. The output ends of the first coupling motor 626 and the second coupling motor 627 are connected to the output end OUT of the coupler through the oil circuit. Connected to the rodless cavity oil port of the boom cylinder 2 in parallel, the accumulator 64 and the dual oil source provided by the hydraulic main pump 4 are respectively coupled through two sets of coupling motors.

1 again, the energy-saving control system of the excavating arm in this embodiment also includes a controller 73 and a working mode switching signal transmitter 74 that are connected to each other in communication, and the working mode switching signal 74 is the working mode of the excavator. Switch button, the controller 73 exchanges with the first pressure sensor 71, the second pressure sensor 72, the electromagnet DT1 of the proportional pressure reducing valve 82 of the main pump displacement control mechanism, the electromagnet DT4 of the shut-off reversing valve 83, and the potential energy recovery and utilization. The energy recovery position switching module DT2 of the direction valve 61 and the energy release module DT3 are communicatively connected. Regarding the feedback control of the controller, the pressure sensing element, and the electromagnet, which is a common automatic control technology in the hydraulic system of the excavator, the circuit or the communication mode connected to the controller 73 will not be described in detail in this embodiment.

When the excavator is powered on, the controller 73 constantly detects the signal of the working mode switching signal transmitter 74. If it is a normal mode signal, the controller 73 never outputs an electric signal to control the electromagnet DT1 of the proportional pressure reducing valve 82 during the working process. Potential energy recovery uses the reversing valve electromagnets DT2 and DT3 in the reversing valve 61, and the electromagnet DT4 of the stop reversing valve 83. All these solenoid valves are in the normal position. At this time, the excavating arm works like a conventional excavator; otherwise, If the controller 73 detects that the signal from the working mode switching signal transmitter 74 is an energy-saving mode signal, it works in the energy-saving mode, and the controller 73 then continuously detects the electrical signals of the first pressure sensor 71 and the second pressure sensor 72 to determine The working state of the boom.

When the controller 73 detects that the first pressure sensor 71 has a signal, it means that the boom down pilot operating valve 52 is outputting pilot pressure oil. At this time, the boom down operation is in progress, and the controller 73 gives the proportional pressure reducing valve 82 The electromagnet DT1 has a certain amount of current to limit the flow of the second main pump 32 into the rod cavity of the boom cylinder. At the same time, the controller 73 also allows the potential energy to be recycled and used in the reversing valve 61. The reversing valve electromagnet DT2 is energized into energy. The recovery position, the energy recovery position has the function of lowering and regenerating the boom cylinder, which makes the rod cavity and rodless cavity of the boom cylinder differentially communicate, so as to realize the boost recovery of the potential energy of the boom, and make the potential energy of the entire boom lowering process equal to the first The energy inputted into the rod cavity by the second main pump 32 just meets the energy of the accumulator designed for boom lifting requirements.

When the controller 73 detects that the pressure transmitter 7 has a signal, it means that the boom lift pilot operating valve 51 is outputting pilot pressure oil. At this time, the boom lift operation is being performed, and the controller 73 turns the shut-off reversing valve 83 is energized to prevent the first boom operating link 41 in the multi-way reversing valve from reversing. The first main pump 31 does not supply oil for boom lifting. At the same time, the controller 73 allows the potential energy to be recycled and used in the reversing valve 61. The reversing valve solenoid DT3 is energized and enters the energy release position. At this time, the pressure oil raised by the boom is supplied by the second main pump 32 and the accumulator 64 respectively, and the dual oil sources in the boom potential energy recovery and utilization device 6 are coupled The device 62 makes the main pump oil source and the accumulator oil source of different characteristics match each other to meet the load demand pressure. Of course, if it is found that the components of the boom potential energy recovery and utilization device 6 are malfunctioning, the signal of the working mode switching signal transmitter 74 can be changed to return to the normal control mode.

The above embodiments only describe the preferred embodiments of the present invention, and do not limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and changes made by those of ordinary skill in the art to the technical solutions of the present invention All improvements should fall within the protection scope determined by the claims of the present invention.

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Claims (10)

1. An energy-saving control system for an excavating boom, which is characterized in that it includes a boom hydraulic system and a boom potential energy recovery and utilization device;

   The boom potential energy recovery and utilization device includes a potential energy recovery and utilization reversing valve, a dual oil source coupler and an accumulator, and the potential energy recovery and utilization reversing valve includes a neutral position, an energy release position and an energy recovery position, wherein,

   The potential energy recovery and utilization reversing valve is located in the middle position, and the two oil chambers of the boom hydraulic system and the two oil chambers of the boom cylinder are directly connected into a loop through the neutral function of the potential energy recovery and utilization reversing valve;

   The potential energy recovery and utilization reversing valve is located in the energy recovery position, and the two oil chambers of the boom cylinder are in differential communication through the potential energy recovery and utilization reversing valve, and are connected to the accumulator and the boom hydraulic system at the same time. Oil circuit

   The potential energy recovery and utilization reversing valve is located at the energy release position, one of the oil chambers of the boom cylinder is connected to the return path of the boom hydraulic system through the potential energy recovery and utilization reversing valve, and the other oil cavity of the boom cylinder passes through the double The oil source coupler is respectively connected to the oil inlet and accumulator of the boom hydraulic system;

   The boom hydraulic system includes two sets of boom operation linkages in the excavator multi-way reversing valve and two sets of main pumps corresponding to the two sets of boom operation linkages. The boom operation linkage is controlled to switch boom lowering and moving. A first pressure sensor and a second pressure sensor are respectively provided on the pilot oil path of the boom lift, and a shut-off valve is provided on the pilot oil path of a group of boom operation linkages, wherein the first pressure sensor is connected to the discharge of the main pump. The quantity control mechanism and the energy recovery position switching module of the potential energy recovery and utilization reversing valve are feedback connected, and the second pressure sensor is feedback connected with the cut-off valve and the energy release position switching module of the potential energy recovery and utilization reversing valve.
2. The energy-saving control system for an excavating arm according to claim 1, wherein the potential energy recovery and utilization reversing valve is a three-position seven-way electro-hydraulic reversing valve, which respectively correspond to the electromagnet at the energy recovery position and the corresponding energy release position The electromagnet is respectively feedback connected with the first pressure sensor and the second pressure sensor. The potential energy recovery and utilization reversing valve has an oil inlet, an oil return, two groups of working oil ports, and three groups of energy-saving oil ports. , Oil return port and two groups of working oil ports are connected to the two oil ports of the boom cylinder and the inlet and outlet oil circuits of the hydraulic system. One group of energy-saving oil ports is connected to the accumulator, and the other two groups of energy-saving oil ports are connected to the double An oil source coupler, the dual oil source coupler is connected in parallel to one of the oil chambers of the boom cylinder, and an energy release check valve is provided on the parallel oil path of the dual oil source coupler and the boom cylinder;

   The potential energy recovery and utilization reversing valve is in the middle position, and the two oil chambers of the boom cylinder and the inlet and outlet oil passages of the hydraulic system pass through the potential energy recovery and utilization reversing valve's oil inlet, oil return port and two sets of work The oil ports are connected to form a loop, and the three groups of energy-saving oil ports are separately blocked;

   The potential energy recovery and utilization reversing valve is located at the energy recovery position, and the two oil chambers of the boom cylinder are in differential communication through the two sets of working oil ports of the potential energy recovery and utilization reversing valve. Are respectively connected to the energy-saving oil port connected to the accumulator and the oil inlet connected to the oil inlet of the hydraulic system, the oil return port and the two groups of energy-saving oil ports connected to the dual oil source coupler are respectively blocked;

   The potential energy recovery and utilization reversing valve is located at the energy release position. One of the oil chambers of the boom cylinder is connected to the oil return path of the hydraulic system through one of the group of working oil ports and the oil inlet, and the other group of working oil ports is cut off and returns to The oil ports are connected to one group of energy-saving oil ports connected to the dual oil source coupler, and the other oil cavity of the boom cylinder is respectively connected to the oil inlet path and the accumulator of the hydraulic system through the dual oil source coupler.
3. The energy-saving control system for an excavating boom according to claim 2, in the energy recovery position of the potential energy recovery and utilization reversing valve, a differential one-way valve is provided to connect the two oil chambers of the boom cylinder The working oil port realizes one-way differential communication.
4. The energy-saving control system for an excavating boom according to claim 3, wherein the dual oil source coupler is a dual-cylinder coupler, comprising a first cylinder and a second cylinder arranged in parallel, the first cylinder and the second cylinder The pistons inside the cylinders are synchronously connected. The internal oil chambers of the first cylinder and the second cylinder are respectively connected to the two sets of energy-saving oil ports of the potential energy recovery and utilization reversing valve, which serve as the oil inlet end of the dual oil source coupler. The other oil chamber of the cylinder or the second cylinder is connected in parallel to one of the oil chambers of the boom oil cylinder through the output end, and the output end of the dual oil source coupler is connected to the oil tank through a one-way oil inlet.
5. According to an energy-saving control system for an excavating arm of claim 4, a return spring for returning the piston is provided inside the double-cylinder coupler.
6. The energy-saving control system for an excavating arm according to claim 2, wherein the dual oil source coupler is a dual motor coupler, comprising two sets of coupled motors arranged in parallel, and the input ends of the two sets of coupled motors are respectively connected To the two groups of energy-saving oil ports of the potential energy recovery and utilization reversing valve, the output ends of the two groups of coupling motors are connected in parallel and then connected in parallel to one of the oil chambers of the boom cylinder.
7. The energy-saving control system for an excavating boom according to claim 1, wherein the displacement control mechanism of the main pump includes a pilot oil circuit at the displacement negative control port, a multi-way reversing valve, and a pilot operated by the boom operation. A signal or valve arranged between the oil sources and a proportional pressure reducing valve between the signal or valve and the pilot oil source connected to the operating arm of the boom. The electromagnet of the proportional pressure reducing valve is feedback connected to the first pressure sensor.
8. The energy-saving control system of an excavating boom according to claim 1, wherein the cut-off valve is a two-position cut-off reversing valve arranged on the pilot oil circuit of the boom operating link, and the electromagnet of the two-position cut-off reversing valve is Feedback connection with the second pressure sensor.
9. An energy-saving control system for an excavating arm according to any one of claims 1-8, further comprising a controller and a working mode switching signal transmitter that are connected in communication, and the controller is connected to the first pressure sensor and the first pressure sensor. 2. The pressure sensor, the displacement control mechanism of the main pump, the shut-off valve, and the energy recovery position switching module of the potential energy recovery and utilization reversing valve are in communication connection with the energy release module.
10. An energy-saving control method for excavating mobile arms, characterized in that: the control system in claims 1-9 is adopted, which includes a conventional control mode and an energy-saving control mode;

    In the normal control mode, the signal of the normal control mode is given to the controller through the working mode switching signal transmitter. The controller does not monitor the first pressure sensor and the second pressure sensor, and the potential energy recovery and utilization reversing valve is in the middle Position, the displacement control mechanism of the main pump and the shut-off valve are in the normal position, and the boom oil cylinder is conventionally controlled by the boom hydraulic system;

    In the energy-saving control mode, the signal of the energy-saving working mode is sent to the controller through the working mode switching signal transmitter, and the controller continuously detects the signals of the first pressure sensor and the second pressure sensor,

    among them,

    When the controller detects the pressure signal sent by the first pressure sensor, the boom of the excavator is in a descending action at this time, and the controller controls the displacement control mechanism of the main pump to reduce the main pump to the boom cylinder pump At the same time, the controller controls the potential energy recovery and utilization reversing valve to be in the energy recovery position, and the potential energy recovery and utilization device of the boom is used to recover the pressure oil transformed by the potential energy of the boom.

    When the controller detects the pressure signal sent by the second pressure sensor, the boom of the excavator is in a lifting action at this time, and the controller controls the shut-off valve to be energized, so that the boom operation corresponding to the shut-off valve is linked Stop supplying oil to the boom cylinder, a set of main pumps of the boom hydraulic system and the boom operation are combined to supply oil to the boom cylinder, and the controller controls the potential energy recovery and utilization reversing valve to be in the energy release position. The oil supply of the hydraulic system, together with the pressure oil recovered by the boom potential energy recovery and utilization device, supplies oil to the boom cylinder.