Intelligent docking block electro-hydraulic control system with mechanical locking function and control method of intelligent docking block electro-hydraulic control system

Abstract

The invention relates to the technical field of shipbuilding and hydraulic control, in particular to an intelligent docking block electro-hydraulic control system with a mechanical locking function and a control method of the intelligent docking block electro-hydraulic control system. The system comprises a hydraulic cylinder, an independent mechanical locking assembly in mechanical coupling locking or unlocking connection with a piston rod of the hydraulic cylinder, a distributed hydraulic oil source and an integrated control valve set, and an oil port P and an oil port T of the distributed hydraulic oil source communicate with an oil port P and an oil port T of the integrated control valve set correspondingly. The integrated control valve group comprises an oil port A1 and an oil port B1 which are respectively communicated with a rodless cavity and a rod cavity of the hydraulic cylinder, and an oil port A2 and an oil port B2 which are communicated with a driving mechanism of the independent mechanical locking assembly. Therefore, the technical problems that in the prior art, a reliable locking function cannot be provided, and when a system is shut down or loses pressure, the locking function is unreliable, safety is insufficient, and potential safety hazards exist are solved.

Description

Technical Field

[0001] This application relates to the fields of shipbuilding and hydraulic control technology, and in particular to an intelligent dock pier electro-hydraulic control system with mechanical locking function and its control method. Background Technology

[0002] Dock blocks, as dry dock infrastructure, primarily function to transfer the weight of ships when they are seated, distributing the ship's weight evenly to the dock floor. Traditional dock blocks consist of steel frames and wooden blocks, making them difficult to adjust and adapt to different ship shapes and curved surfaces. For different ship shapes and curved surfaces, traditional dock blocks require workers to assemble fixed blocks, movable blocks, wooden wedges, and pads of varying heights to the required height, then hoist and install them layer by layer. This method is not only cumbersome, labor-intensive, and time-consuming, but also fails to accurately meet the complex curved surface support requirements of different ship shapes, impacting the efficiency and precision of shipbuilding and maintenance.

[0003] Currently, existing technologies can utilize hydraulically driven, liftable docking piers to improve the automation and intelligence levels of shipbuilding. For example, invention patent application number 201310266179.0 discloses a movable hydraulic docking pier and its usage method. This hydraulic docking pier includes a fixed support bracket, four hydraulic cylinders, a vertically movable bracket, a horizontally movable bracket, a steel ball spacer, and a traveling mechanism assembly. The four hydraulic cylinders serve as the four support points of the docking pier and are located at the four corners of the fixed support bracket. The vertically movable bracket is located above the four hydraulic cylinders, and the horizontally movable bracket is fixedly mounted on the vertically movable bracket. A steel ball spacer is installed between the horizontally movable bracket and the vertically movable bracket. Through the coordinated lifting of multiple sets of hydraulic cylinders, efficient positioning of heavy-load sections can be achieved. However, this existing solution lacks high-precision position holding control and hydraulic locking protection mechanisms, resulting in compromised stability and potential safety hazards.

[0004] For example, invention patent application number 202111425860.6 discloses a novel universal dock pier based on hydraulic automatic control. It adopts a separate center and side pier structure. The side pier assembly includes adjustable side pier components, a mobile hydraulic station, and a measurement and control system. The longitudinal distance between each set of adjustable side pier components is arranged according to the actual needs of different ship types, and the lateral position relative to the center pier is adjusted according to different ship types. A sleeve-type locking lifting hydraulic cylinder and a sleeve-type locking adjusting hydraulic cylinder are used to achieve stepless adjustment of the height of the adjustable side pier components and the angle of the adjustable side pier component rotation plate. Although this prior art improves in attitude adaptability and operational convenience, its sleeve-type locking structure is essentially a hydraulic lock. Its locking function and the maintenance of the locking state completely depend on the power of the hydraulic system. When the system stops or loses pressure, the locking function is unreliable and cannot be maintained, resulting in insufficient safety and reliability and potential safety hazards. Summary of the Invention

[0005] The purpose of this application is to provide an intelligent dock pier electro-hydraulic control system and control method with mechanical locking function, so as to solve the technical problem that the existing technology cannot provide a reliable locking function, and the locking function is unreliable and the safety is insufficient when the system stops or loses pressure, thus posing a safety hazard.

[0006] In the first aspect, this application provides an intelligent dock pier electro-hydraulic control system with mechanical locking function, including: a hydraulic cylinder, an independent mechanical locking assembly, a distributed hydraulic oil source, and an integrated control valve group; The independent mechanical locking assembly is mechanically coupled to the piston rod of the hydraulic cylinder for locking or unlocking. The P port and T port of the distributed hydraulic oil source are respectively connected to the P port and T port of the integrated control valve group to provide driving power; The integrated control valve group includes ports A1 and B1, which are connected to the rodless chamber and rod chamber of the hydraulic cylinder respectively via hydraulic lines, and ports A2 and B2, which are connected to the drive mechanism of the independent mechanical locking assembly via hydraulic lines.

[0007] Furthermore, the independent mechanical locking assembly includes: an external gear locking nut that is mechanically connected to the piston rod of the hydraulic cylinder through a threaded pair; a drive gear that is meshed with the external gear locking nut through an external gear pair; and a hydraulic motor whose output shaft is connected to the drive gear through a spline. The hydraulic motor is the drive mechanism, and the oil inlet and outlet of the hydraulic motor are respectively connected to the A2 oil port and the B2 oil port of the integrated control valve group through hydraulic pipelines.

[0008] Furthermore, the distributed hydraulic oil source includes a hydraulic oil tank, a motor-hydraulic pump unit, a check valve, a proportional relief valve, a two-way solenoid valve, a high-pressure filter, a manual pump, and a first relief valve; The oil inlet of the motor-hydraulic pump unit is connected to the hydraulic oil tank; the oil outlet of the motor-hydraulic pump unit is connected to the oil inlet of the one-way valve; the oil outlet of the one-way valve is connected to the P port of the two-way solenoid valve and the oil inlet of the high-pressure filter; the A port of the two-way solenoid valve is connected to the P port of the proportional relief valve; the T port of the proportional relief valve is connected to the hydraulic oil tank; the oil outlet of the high-pressure filter is connected to the P port of the integrated control valve group; and the T port of the integrated control valve group is connected to the hydraulic oil tank. The oil outlet of the manual pump and the P port of the first relief valve are both connected to the oil outlet of the check valve, and the oil suction port of the manual pump and the T port of the first relief valve are both connected to the hydraulic oil tank.

[0009] Furthermore, the integrated control valve assembly includes a pressure reducing valve, a solenoid directional valve, and a second one-way throttle valve; Specifically, the P port and T port of the pressure reducing valve are connected to the P port and T port of the integrated control valve group, respectively; the A port of the pressure reducing valve is connected to the P port of the solenoid directional valve; the T port of the solenoid directional valve is connected to the T port of the integrated control valve group; the A port and B port of the solenoid directional valve are connected to the A1 port and B1 port of the second one-way throttle valve, respectively; and the A2 port and B2 port of the second one-way throttle valve are connected to the A2 port and B2 port of the integrated control valve group.

[0010] Furthermore, the integrated control valve group also includes a proportional servo valve, a first normally closed solenoid ball valve, a second normally closed solenoid ball valve, a third normally closed solenoid ball valve, a first safety valve, and a second safety valve. The P port of the first normally closed solenoid ball valve is connected to the P port of the integrated control valve group; the A port of the first normally closed solenoid ball valve is connected to the P port of the proportional servo valve; the T port of the proportional servo valve is connected to the T port of the integrated control valve group; the A and B ports of the proportional servo valve are respectively connected to the P ports of the second normally closed solenoid ball valve and the third normally closed solenoid ball valve; and the A ports of the second normally closed solenoid ball valve and the third normally closed solenoid ball valve are respectively connected to the A1 and B1 ports of the integrated control valve group. The A port of the second normally closed solenoid ball valve and the A port of the third normally closed solenoid ball valve are also connected to the P port of the first safety valve and the P port of the second safety valve, respectively. The T port of the first safety valve and the T port of the second safety valve are connected to the T port of the integrated control valve group.

[0011] Furthermore, the integrated control valve assembly also includes a manual directional valve, a first one-way throttle valve, a first manual ball valve, and a second manual ball valve; The P port and T port of the manual directional valve are respectively connected to the P port and T port of the integrated control valve group. The A port and B port of the manual directional valve are respectively connected to the A1 port and B1 port of the first one-way throttle valve. The A2 port and B2 port of the first one-way throttle valve are respectively connected to the inlet port of the first manual ball valve and the inlet port of the second manual ball valve. The outlet ports of the first manual ball valve and the second manual ball valve are respectively connected to the B1 port and A1 port of the integrated control valve group.

[0012] Furthermore, the intelligent dock pier electro-hydraulic control system with mechanical locking function also includes a PLC control system and a sensor group electrically connected to the PLC control system, the sensor group including: A first pressure sensor, a second pressure sensor, a third pressure sensor, and a fourth pressure sensor are respectively connected to the A1 port, the B1 port, the A2 port, and the B2 port of the integrated control valve group; A displacement sensor is installed outside the hydraulic cylinder to measure the displacement of the hydraulic cylinder; A first proximity switch, a second proximity switch, and a third proximity switch are arranged sequentially from bottom to top and located on one side of the external gear locking nut, respectively indicating the locked position, retracted position, and extended position of the external gear locking nut.

[0013] Furthermore, the PLC control system includes a CPU module, an AI module, a DI module, an AO module, and a DO module; The AI ​​module is electrically connected to the first pressure sensor, the second pressure sensor, the third pressure sensor, the fourth pressure sensor, and the displacement sensor, and is used to receive pressure analog signals and displacement analog signals; The DI module is electrically connected to the first proximity switch, the second proximity switch and the third proximity switch, and is used to receive position status switch signals; The AO module is electrically connected to the proportional relief valve and the proportional servo valve, and is used to output current signals to control the pressure and opening degree of the proportional relief valve and the proportional servo valve; The DO module is electrically connected to the two-way solenoid valve, the first normally closed solenoid ball valve, the second normally closed solenoid ball valve, the third normally closed solenoid ball valve, and the solenoid directional valve, and is used to output a switching signal to control their on / off state.

[0014] Secondly, this application provides a control method for an intelligent dock pier electro-hydraulic control system with mechanical locking function, applied to the intelligent dock pier electro-hydraulic control system with mechanical locking function described in any one of the preceding claims. The control method includes: S11, start oil supply, control the two-way solenoid valve of the distributed hydraulic oil source to be energized and start the motor hydraulic pump group, and adjust the oil supply pressure to the preset value by adjusting the current of the proportional relief valve; S12, unlock the hydraulic cylinder, control the solenoid directional valve of the integrated control valve group so that the hydraulic motor drives the external gear locking nut through the drive gear to enter the unlocking operation: the external gear locking nut first disengages from the first proximity switch, and then gradually moves between the second proximity switch and the third proximity switch, and the unlocking operation is completed; S13 enables the proportional servo valve and controls the second normally closed solenoid ball valve, the third normally closed solenoid ball valve, and the first normally closed solenoid ball valve to be energized. Thus, the movement of the hydraulic cylinder is completely controlled by the proportional servo valve. S14, closed-loop position control of hydraulic cylinder: The PLC control system calculates the current position deviation based on the target position curve information of the hydraulic cylinder sent by the upper control system through the fieldbus and the real-time position feedback of the displacement sensor. Then, based on the position control algorithm, it calculates the opening command of the proportional servo valve and controls the opening degree of the proportional servo valve according to the opening command. The high-pressure oil supplied by the distributed hydraulic oil source generates a driving flow through the proportional servo valve to drive the hydraulic cylinder, so that the hydraulic cylinder tracks the target position curve sent by the upper control system.

[0015] Furthermore, the control method for the intelligent dock pier electro-hydraulic control system with mechanical locking function further includes: External gear locking nut follow-up control method: As the hydraulic cylinder continuously moves in response to the target position curve issued by the upper control system, the external gear locking nut follows the movement of the hydraulic cylinder according to the following follow-up control strategy: S2a. During the lifting process of the hydraulic cylinder, once the external gear locking nut touches the third proximity switch, the solenoid directional valve is controlled to make the hydraulic motor drive the external gear locking nut through the drive gear to perform the locking operation. Once the external gear locking nut touches the second proximity switch, the solenoid directional valve is controlled to stop the hydraulic motor. At the same time, the opening of the second one-way throttle valve is set so that the speed at which the hydraulic motor drives the external gear locking nut to perform the locking operation is faster than the lifting speed of the hydraulic cylinder. S2b. During the retraction of the hydraulic cylinder, once the external gear locking nut touches the second proximity switch, the solenoid directional valve is controlled to make the hydraulic motor drive the external gear locking nut through the drive gear to perform the unlocking operation. Once the external gear locking nut touches the third proximity switch, the solenoid directional valve is controlled to stop the hydraulic motor. At the same time, the opening of the second one-way throttle valve is set so that the speed at which the hydraulic motor drives the external gear locking nut to perform the unlocking operation is faster than the retraction speed of the hydraulic cylinder.

[0016] and / or Shutdown control methods include: S31. Locking the hydraulic cylinder: Control the solenoid directional valve to make the hydraulic motor drive the external gear locking nut through the drive gear to perform the locking operation until the external gear locking nut touches the first proximity switch. The locking operation is completed and the hydraulic cylinder is reliably locked in the current stop position. S32, De-energize the second normally closed solenoid ball valve, the third normally closed solenoid ball valve, and the first normally closed solenoid ball valve, and cut off the enable signal of the proportional servo valve. S33. Gradually reduce the current of the proportional relief valve to zero, depressurize the distributed hydraulic oil source, stop the control motor hydraulic pump group, and de-energize the two-way solenoid valve.

[0017] Compared with the prior art, the intelligent dock pier electro-hydraulic control system and its control method with mechanical locking function provided in this application mechanically locks or unlocks the hydraulic cylinder by setting an independent mechanical locking component that is mechanically coupled to the piston rod of the hydraulic cylinder. The locking or unlocking action is driven and controlled by an integrated control valve group, and the driving action is powered by a distributed hydraulic oil source. At the same time, the integrated control valve group and the distributed hydraulic oil source also provide drive control and power support for the hydraulic cylinder.

[0018] With this configuration, this application employs an independent mechanical locking component. Utilizing its purely mechanical locking principle, although the locking and unlocking actions are controlled by an integrated control valve group, once locked, its locking state is maintained solely by the physical characteristics of mechanical locking, independent of any external power system. Compared to existing technologies, it provides relatively permanent locking protection. Even when the system stops or loses pressure, its locking state remains unaffected, continuously maintaining the lock, ensuring high safety and reliability, and eliminating the safety hazards of existing technologies. Furthermore, this independent mechanical locking component is located outside the hydraulic cylinder, rather than being an integrated part inside the hydraulic cylinder. Even if the internal seals of the hydraulic cylinder completely fail and all oil leaks out, the mechanical locking state remains effective, further ensuring its safety and reliability. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0020] Figure 1 This is a hydraulic schematic diagram of the intelligent dock electro-hydraulic control system provided in the embodiments of this application; Figure 2 This is a schematic diagram of the structure of the intelligent dock electro-hydraulic control system provided in the embodiments of this application; Figure 3 This is a schematic diagram of the PLC control system provided in an embodiment of this application; Figure 4 This is a flowchart illustrating the hydraulic cylinder closed-loop position control method of the control method for the intelligent dock electro-hydraulic control system provided in the embodiments of this application.

[0021] Figure label: 10-Hydraulic cylinder; 11-Piston rod; 20 - Independent mechanical locking assembly; 21 - External gear lock nut; 22-Drive gear; 23-Hydraulic motor; 30 - Distributed hydraulic oil source; 31-Hydraulic oil tank; 32-Electric motor hydraulic pump set; 33 - Check valve; 34 - Proportional relief valve; 35 - Two-way solenoid valve; 36 - High-pressure filter; 37 - Manual pump; 38 - First relief valve; 40 - Integrated control valve assembly; 43-Proportional servo valve; 441 - First normally closed solenoid ball valve; 442 - Second normally closed solenoid ball valve; 443 - Third normally closed solenoid ball valve; 451 - First safety valve; 452 - Second safety valve; 461 - Manual directional valve; 462 - First one-way throttle valve; 463 - First manual ball valve; 464 - Second manual ball valve; 471 - Pressure reducing valve; 472 - Electromagnetic directional valve; 473 - Second one-way throttle valve; 511 - First pressure sensor; 512 - Second pressure sensor; 513 - Third pressure sensor; 514 - Fourth pressure sensor; 52-Displacement sensor; 531 - First proximity switch; 532 - Second proximity switch; 533 - Third Proximity Switch; 60-PLC control system; 61-CPU module; 62-AI module; 63-DI module; 64-AO module; 65-DO module. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0023] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0024] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0025] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this application is in use. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. In addition, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0026] Furthermore, terms such as "horizontal," "vertical," and "sag" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0027] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "set up," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0028] The following detailed description of some embodiments of this application is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0029] like Figures 1 to 4 As shown in the figure, this application provides an intelligent dock pier electro-hydraulic control system with mechanical locking function, and a control method applied to the system.

[0030] like Figure 1 and Figure 2 As shown in the embodiment of this application, the intelligent dock pier electro-hydraulic control system with mechanical locking function includes a hydraulic cylinder 10, an independent mechanical locking assembly 20, a distributed hydraulic oil source 30, and an integrated control valve group 40.

[0031] The independent mechanical locking assembly 20 is mechanically coupled to the piston rod 11 of the hydraulic cylinder 10 for locking or unlocking; the P port and T port of the distributed hydraulic oil source 30 are respectively connected to the P port and T port of the integrated control valve group 40 to provide driving power; the A1 port and B1 port of the integrated control valve group 40 are respectively connected to the rodless chamber and the rod chamber of the hydraulic cylinder 10; the A2 port and B2 port of the integrated control valve group 40 are connected to the drive mechanism of the independent mechanical locking assembly 20.

[0032] Compared with the prior art, the intelligent dock electro-hydraulic control system and its control method with mechanical locking function provided in this application embodiment are achieved by setting an independent mechanical locking component 20 that is mechanically coupled to the piston rod 11 of the hydraulic cylinder 10 for mechanical locking or unlocking. The locking or unlocking action is driven by an integrated control valve group 40, and the driving action is powered by a distributed hydraulic oil source 30. At the same time, the integrated control valve group 40 and the distributed hydraulic oil source 30 also provide drive control and power support for the hydraulic cylinder 10.

[0033] With this configuration, this application employs an independent mechanical locking component 20. Utilizing its purely mechanical locking principle, although the locking and unlocking actions are controlled by the integrated control valve group 40, once locked, its locking state is maintained solely by the physical characteristics of mechanical locking, independent of any external power system. Compared to existing technologies, it provides relatively permanent locking protection. Even when the system stops or loses pressure, its locking state remains unaffected, continuously maintaining the lock, ensuring high safety and reliability, and eliminating the safety hazards of existing technologies. Furthermore, this independent mechanical locking component 20 is installed independently of the hydraulic cylinder 10, rather than being an integrated component within the hydraulic cylinder 10. Even if the internal seals of the hydraulic cylinder 10 completely fail and all oil leaks out, the mechanical locking state remains effective, further ensuring its safety and reliability.

[0034] like Figure 1 and Figure 2 As shown, in a further preferred embodiment, the independent mechanical locking assembly 20 may specifically include: an external gear locking nut 21 that is mechanically connected to the piston rod 11 of the hydraulic cylinder 10 through a threaded pair; a drive gear 22 that is meshed with the external gear locking nut 21 through an external gear pair; and a hydraulic motor 23 whose output shaft is connected to the drive gear 22 through a spline. The oil inlet and outlet of the hydraulic motor 23 are respectively connected to the A2 oil port and B2 oil port of the integrated control valve group 40 through hydraulic pipelines.

[0035] This purely mechanical threaded locking structure offers high locking force, reliable self-locking, and reliable gear-thread transmission. It converts the rotational motion of the hydraulic motor 23 into a reliable axial locking force, resulting in a compact structure and high mechanical efficiency. This invention uses the hydraulic motor 23 to drive the external gear locking nut 21 to mechanically lock the hydraulic cylinder 10 to its stop position. This ensures that even in the event of electrical or hydraulic failure, the hydraulic cylinder 10 can still be reliably locked in the stop position, providing sufficient support for the workpiece and ensuring equipment safety.

[0036] like Figure 1 As shown, regarding the aforementioned distributed hydraulic oil source 30, a specific embodiment is that the distributed hydraulic oil source 30 may include a hydraulic oil tank 31, a motor-hydraulic pump group 32, a one-way valve 33, a proportional relief valve 34, a two-way solenoid valve 35, and a high-pressure filter 36.

[0037] Specifically, the suction port of the motor-hydraulic pump assembly 32 is connected to the hydraulic oil tank 31, the outlet port of the motor-hydraulic pump assembly 32 is connected to the inlet port of the one-way valve 33, the outlet port of the one-way valve 33 is connected to the P port of the two-way solenoid valve 35 and the inlet port of the high-pressure filter 36, the A port of the two-way solenoid valve 35 is connected to the P port of the proportional relief valve 34, the T port of the proportional relief valve 34 is connected to the hydraulic oil tank 31, the outlet port of the high-pressure filter 36 is connected to the P port of the integrated control valve assembly 40, and the T port of the integrated control valve assembly 40 is connected to the hydraulic oil tank 31.

[0038] With this configuration, the distributed hydraulic oil source 30 supplies oil to the integrated control valve group 40 through the motor-hydraulic pump group 32. The oil supply pressure is adjusted as needed by the proportional relief valve 34, which can effectively reduce the heat generation of the distributed hydraulic oil source 30. The two-way solenoid valve 35 can serve as a switch for switching the system pressure control mode and a safety pressure relief valve. Only when the two-way solenoid valve 35 is energized can the oil supply pressure be adjusted and controlled as needed through the proportional relief valve 34. Conversely, when the two-way solenoid valve 35 is de-energized, the emergency first relief valve 38 can be used for control, entering a low-pressure, safe, pressure relief, or emergency state. The high-pressure filter 36 serves as a filter and protection for the high-pressure pipeline oil.

[0039] Furthermore, the distributed hydraulic oil source may also include a manual pump 37 and a first relief valve 38. The oil outlet of the manual pump 37 and the P port of the first relief valve 38 are both connected to the oil outlet of the aforementioned check valve 33. The oil suction port of the manual pump 37 and the T port of the first relief valve 38 are both connected to the aforementioned hydraulic oil tank 31.

[0040] With this configuration, in the event of a failure of the PLC control system 60, the distributed hydraulic oil source 30 can supply emergency oil to the integrated control valve group 40 by controlling the manual pump 37, and the oil supply pressure can be limited by the first relief valve 38.

[0041] like Figure 1 As shown, regarding the aforementioned integrated control valve group 40, in one specific embodiment, the integrated control valve group 40 may include a pressure reducing valve 471, a solenoid directional valve 472, and a second one-way throttle valve 473.

[0042] Specifically, the P port and T port of the pressure reducing valve 471 are connected to the P port and T port of the integrated control valve group 40, respectively. The A port of the pressure reducing valve 471 is connected to the P port of the solenoid directional valve 472, and the T port of the solenoid directional valve 472 is connected to the T port of the integrated control valve group 40. This reduces the high-pressure oil source in the main oil circuit of the integrated control valve group 40 to a stable, preset low-pressure oil source specifically for driving the hydraulic motor 23 of the locking mechanism. On the one hand, the stable low pressure protects the precision mechanical components, prevents overload locking, and improves control accuracy and stability. On the other hand, it effectively prevents the waste of high-pressure energy.

[0043] Specifically, the A port and B port of the electromagnetic reversing valve 472 are connected to the A1 port and B1 port of the second one-way throttle valve 473, respectively, and the A2 port and B2 port of the second one-way throttle valve 473 are connected to the A2 port and B2 port of the integrated control valve group 40.

[0044] With this configuration, the direction of rotation of the hydraulic motor 23 is controlled by controlling the solenoid directional valve 472, so that the external gear locking nut 21 is rotated to lock or unlock via the drive gear 22, and at the same time, it effectively follows the position of the hydraulic cylinder 10.

[0045] Furthermore, in an alternative embodiment, the integrated control valve assembly 40 may further include a proportional servo valve 43, a first normally closed solenoid ball valve 441, a second normally closed solenoid ball valve 442, and a third normally closed solenoid ball valve 443.

[0046] Specifically, the P port of the first normally closed solenoid ball valve 441 is connected to the P port of the integrated control valve group 40, and the A port of the first normally closed solenoid ball valve 441 is connected to the P port of the proportional servo valve 43. The T port of the proportional servo valve 43 is connected to the T return port of the integrated control valve group 40. This positions the first normally closed solenoid ball valve 441 between the inlet of the main oil circuit of the integrated control valve group 40 and the inlet of the proportional servo valve 43, acting as a master switch for pressurized oil entering the proportional servo valve circuit. In the shutdown or non-working state, the first normally closed solenoid ball valve 441 is de-energized and closed. At this time, the proportional servo valve 43 is in an unloaded state to prevent internal leakage, jamming, or zero drift caused by long-term pressure, thus extending its service life and ensuring the stability of the system's initial state. Furthermore, this application can precisely adjust the position of the hydraulic cylinder 10 through the proportional servo valve 43, with simple state adjustment, and can meet the support requirements of various ship-shaped curved surfaces.

[0047] More specifically, the A1 port of the integrated control valve assembly 40 can be connected to the rodless chamber of the hydraulic cylinder 10, the B1 port of the integrated control valve assembly 40 can be connected to the rod chamber of the hydraulic cylinder 10, and the A port of the second normally closed solenoid ball valve 442 and the A port of the third normally closed solenoid ball valve 443 can be connected to the A1 port and the B1 port of the integrated control valve assembly 40, respectively. At the same time, the A port and the B port of the proportional servo valve 43 can be connected to the P port of the second normally closed solenoid ball valve 442 and the P port of the third normally closed solenoid ball valve 443, respectively.

[0048] This enables independent control of the dual chambers of the hydraulic cylinder, allowing for both independent and coordinated control. When the system stops or needs to maintain its position, the second normally closed solenoid ball valve 442 and the third normally closed solenoid ball valve 443 can be de-energized simultaneously, achieving a dual hydraulic lock-up state. In this state, regardless of the action of the proportional servo valve 43, the hydraulic cylinder 10 cannot move and is firmly locked in its current position. This is a safety preparation state before mechanical locking.

[0049] In a further embodiment, the integrated control valve assembly 40 may also include a first safety valve 451 and a second safety valve 452 to provide further safety protection.

[0050] Specifically, the A port of the second normally closed solenoid ball valve 442 and the A port of the third normally closed solenoid ball valve 443 are respectively connected to the P port of the first safety valve 451 and the P port of the second safety valve 452, and the T port of the first safety valve 451 and the T port of the second safety valve 452 are connected to the T port of the integrated control valve group 40.

[0051] In another further embodiment, the integrated control valve assembly 40 may also include a manual directional valve 461, a first one-way throttle valve 462, a first manual ball valve 463, and a second manual ball valve 464 connected thereto.

[0052] Specifically, the P port and T port of the manual directional valve 461 are connected to the P port and T port of the integrated control valve group 40, respectively. The A port and B port of the manual directional valve 461 are connected to the A1 port and B1 port of the first one-way throttle valve 462, respectively. The A2 port and B2 port of the first one-way throttle valve 462 are connected to the inlet port of the first manual ball valve 463 and the inlet port of the second manual ball valve 464, respectively. The outlet ports of the first manual ball valve 463 and the second manual ball valve 464 are connected to the B1 port and A1 port of the integrated control valve group 40, respectively, for manual control.

[0053] With this setup, in the event of a failure of the PLC control system 60, the first manual ball valve 463 and the second manual ball valve 464 can be opened, and the emergency action of the hydraulic cylinder 10 can be achieved through the manual directional valve 461. Furthermore, the emergency action of the hydraulic motor 23 can be achieved by operating the manual control device built into the electromagnetic directional valve 472.

[0054] A preferred embodiment is, as follows: Figures 1 to 3 As shown, the intelligent dock electro-hydraulic control system provided in this application embodiment may further include a PLC control system 60 and a sensor group electrically connected to the PLC control system 60.

[0055] Specifically, such as Figure 3 As shown, the PLC control system 60 may include a CPU module 61 (i.e., a programmable logic controller), an AI module 62 (i.e., an analog input module), a DI module 63 (i.e., a digital input module), an AO module 64 (i.e., an analog output module), and a DO module 65 (i.e., a digital output module). The AO module 64 is electrically connected to the aforementioned proportional relief valve 34 and proportional servo valve 43, and is used to output current signals to control the pressure and opening degree of the proportional relief valve 34 and proportional servo valve 43. The DO module 65 is electrically connected to the aforementioned two-way solenoid valve 35, the first normally closed solenoid ball valve 441, the second normally closed solenoid ball valve 442, the third normally closed solenoid ball valve 443, and the solenoid directional valve 472, and is used to output switching signals to control their on / off states.

[0056] Specifically, such as Figure 1As shown, the sensor group may include: a first pressure sensor 511, a second pressure sensor 512, a third pressure sensor 513, and a fourth pressure sensor 514 respectively connected to the A1 port, B1 port, A2 port, and B2 port of the integrated control valve group 40; and a displacement sensor 52 disposed outside the hydraulic cylinder 10 for measuring the displacement of the hydraulic cylinder 10. The first pressure sensor 511, the second pressure sensor 512, the third pressure sensor 513, the fourth pressure sensor 514, and the displacement sensor 52 are also electrically connected to the AI ​​module 62 of the PLC control system 60 to transmit pressure analog signals and displacement analog signals to the AI ​​module 62.

[0057] Furthermore, the sensor group also includes a first proximity switch 531, a second proximity switch 532, and a third proximity switch 533, which are arranged sequentially from bottom to top and located on one side of the aforementioned external gear locking nut 21. They respectively indicate the locked position, retracted position, and extended position of the external gear locking nut 21. The first proximity switch 531, the second proximity switch 532, and the third proximity switch 533 are also electrically connected to the DI module 63 of the PLC control system 60 to transmit position status switch signals to the DI module 63.

[0058] With this configuration, the distributed hydraulic oil source 30 can be controlled by the PLC control system 60 to supply oil to the integrated control valve group 40 through the motor hydraulic pump group 32. The oil supply pressure is adjusted as needed by the proportional relief valve 34, which can effectively reduce the heat generation of the distributed hydraulic oil source 30.

[0059] Correspondingly, this application also provides a control method for an intelligent dock pier electro-hydraulic control system with mechanical locking function, applied to the aforementioned intelligent dock pier electro-hydraulic control system with mechanical locking function. This control method may include: S11, start oil supply, control the two-way solenoid valve 35 of the distributed hydraulic oil source 30 to be energized and the motor hydraulic pump group 32 to start, and adjust the oil supply pressure to the preset value by adjusting the current of the proportional relief valve 34. S12, unlock hydraulic cylinder 10, control the solenoid directional valve 472 of integrated control valve group 40 so that hydraulic motor 23 drives external gear locking nut 21 through drive gear 22 to enter the unlocking operation: external gear locking nut 21 first disengages from first proximity switch 531, and then gradually moves between second proximity switch 532 and third proximity switch 533, and the unlocking operation is completed; S13 enables the proportional servo valve 43 and controls the second normally closed solenoid ball valve 442, the third normally closed solenoid ball valve 443, and the first normally closed solenoid ball valve 441 to be energized. Thus, the movement of the hydraulic cylinder 10 is completely controlled by the proportional servo valve 43. S14, closed-loop position control of hydraulic cylinder 10, such as Figure 4As shown, the PLC control system 60 calculates the current position deviation based on the target position curve information of the hydraulic cylinder 10 sent by the upper control system through the fieldbus and the real-time position feedback of the displacement sensor 52. Then, based on the position control algorithm (usually using the PID algorithm), it calculates the opening command of the proportional servo valve 43, and controls the opening degree of the proportional servo valve 43 according to the opening command. The high-pressure oil supplied by the distributed hydraulic oil source 30 generates a driving flow through the proportional servo valve 43 to drive the hydraulic cylinder 10, so that the hydraulic cylinder 10 tracks the target position curve sent by the upper control system.

[0060] Using the above method, high-precision closed-loop position control of hydraulic cylinder 10 can be achieved intelligently and automatically, enabling precise tracking of hydraulic cylinder 10.

[0061] A further embodiment is that the control method provided in this application may also include an external gear locking nut follow-up control method, comprising: as the hydraulic cylinder 10 continuously moves in tracking the target position curve issued by the upper control system, the external gear locking nut 21 follows the movement of the hydraulic cylinder 10 according to the following follow-up control strategy: S2a. During the lifting process of the hydraulic cylinder 10, once the external gear locking nut 21 touches the third proximity switch 533, the solenoid reversing valve 472 is controlled to make the hydraulic motor 23 drive the external gear locking nut 21 through the drive gear 22 to perform locking operation. Once the external gear locking nut 21 touches the second proximity switch 532, the solenoid reversing valve 472 is controlled to make the hydraulic motor 23 stop operating. At the same time, the opening of the second one-way throttle valve 473 is set so that the speed at which the hydraulic motor 23 drives the external gear locking nut 21 to perform locking operation is faster than the lifting speed of the hydraulic cylinder 10. S2b. During the retraction of the hydraulic cylinder 10, once the external gear locking nut 21 touches the second proximity switch 532, the solenoid directional valve 472 is controlled to make the hydraulic motor 23 drive the external gear locking nut 21 through the drive gear 22 to perform the unlocking operation. Once the external gear locking nut 21 touches the third proximity switch 533, the solenoid directional valve 472 is controlled to make the hydraulic motor 23 stop operating, and at the same time, the opening of the second one-way throttle valve 473 is set so that the speed at which the hydraulic motor 23 drives the external gear locking nut 21 to perform the unlocking operation is faster than the retraction speed of the hydraulic cylinder 10.

[0062] By setting the above method, the external gear locking nut 21 can be precisely locked to the hydraulic cylinder 10 according to the changes in its movement, making the mechanical locking dynamic and further improving the active safety of the system.

[0063] Another further embodiment is that the control method provided in this application may further include: Shutdown control methods include: S31. Lock the hydraulic cylinder 10, control the solenoid reversing valve 472 to make the hydraulic motor 23 drive the external gear locking nut 21 through the drive gear 22 to perform the locking operation until the external gear locking nut 21 touches the first proximity switch 531, the locking operation is completed, and the hydraulic cylinder 10 is reliably locked in the current stop position. S32, de-energize the second normally closed solenoid ball valve 442, the third normally closed solenoid ball valve 443, and the first normally closed solenoid ball valve 441, and cut off the enable signal of the proportional servo valve 43. S33. Gradually reduce the current of the proportional relief valve 34 to zero, depressurize the distributed hydraulic oil source 30, stop the motor hydraulic pump group 32, and de-energize the two-way solenoid valve 35.

[0064] In the above-mentioned shutdown control method, the mechanical locking action (i.e., the hydraulic motor 23 driving the external gear to tighten the locking nut 21) is set as a necessary pre-step in the normal shutdown process. This ensures that even if the system stops, loses pressure, or the PLC system fails, the hydraulic cylinder 10 remains in the locked state. Once mechanically locked, the maintenance of its locked state is a purely physical characteristic of mechanical locking, which does not depend on the support of any external power system. Even if the motor-hydraulic pump group 32 stops, the system pressure is lost, or even if the pipeline ruptures and leaks oil, the mechanical locking nut will still remain locked, providing a highly reliable safety guarantee.

[0065] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. An intelligent dock pier electro-hydraulic control system with mechanical locking function, characterized in that, include: Hydraulic cylinder (10), independent mechanical locking assembly (20), distributed hydraulic oil source (30) and integrated control valve group (40); The independent mechanical locking assembly (20) is mechanically coupled to the piston rod (11) of the hydraulic cylinder (10) for locking or unlocking connection; The P port and T port of the distributed hydraulic oil source (30) are respectively connected to the P port and T port of the integrated control valve group (40) to provide driving power; The integrated control valve group (40) includes an A1 port and a B1 port that are connected to the rodless chamber and the rod chamber of the hydraulic cylinder (10) respectively via hydraulic lines, and an A2 port and a B2 port that are connected to the drive mechanism of the independent mechanical locking assembly (20) via hydraulic lines.

2. The intelligent dock pier electro-hydraulic control system with mechanical locking function according to claim 1, characterized in that, The independent mechanical locking assembly (20) includes: an external gear locking nut (21) mechanically connected to the piston rod (11) of the hydraulic cylinder (10) through a threaded pair; a drive gear (22) meshing with the external gear locking nut (21) through an external gear pair; and a hydraulic motor (23) whose output shaft is connected to the drive gear (22) through a spline. The hydraulic motor is the drive mechanism, and the oil inlet and outlet of the hydraulic motor (23) are respectively connected to the A2 oil port and the B2 oil port of the integrated control valve group (40) through hydraulic pipelines.

3. The intelligent dock pier electro-hydraulic control system with mechanical locking function according to claim 2, characterized in that, The distributed hydraulic oil source (30) includes a hydraulic oil tank (31), a motor-hydraulic pump group (32), a check valve (33), a proportional relief valve (34), a two-way solenoid valve (35), a high-pressure filter (36), a manual pump (37), and a first relief valve (38). The oil inlet of the motor-hydraulic pump assembly (32) is connected to the hydraulic oil tank (31), the oil outlet of the motor-hydraulic pump assembly (32) is connected to the oil inlet of the check valve (33), the oil outlet of the check valve (33) is connected to the P port of the two-way solenoid valve (35) and the oil inlet of the high-pressure filter (36), the A port of the two-way solenoid valve (35) is connected to the P port of the proportional relief valve (34), the T port of the proportional relief valve (34) is connected to the hydraulic oil tank (31), the oil outlet of the high-pressure filter (36) is connected to the P port of the integrated control valve assembly (40), and the T port of the integrated control valve assembly (40) is connected to the hydraulic oil tank (31). The oil outlet of the manual pump (37) and the P port of the first overflow valve (38) are both connected to the oil outlet of the check valve (33), and the oil suction port of the manual pump (37) and the T port of the first overflow valve (38) are both connected to the hydraulic oil tank (31).

4. The intelligent dock pier electro-hydraulic control system with mechanical locking function according to claim 3, characterized in that, The integrated control valve group (40) includes a pressure reducing valve (471), a solenoid directional valve (472), and a second one-way throttle valve (473). The P port and T port of the pressure reducing valve (471) are connected to the P port and T port of the integrated control valve group (40), respectively. The A port of the pressure reducing valve (471) is connected to the P port of the solenoid directional valve (472). The T port of the solenoid directional valve (472) is connected to the T port of the integrated control valve group (40). The A port and B port of the solenoid directional valve (472) are connected to the A1 port and B1 port of the second one-way throttle valve (473), respectively. The A2 port and B2 port of the second one-way throttle valve (473) are connected to the A2 port and B2 port of the integrated control valve group (40).

5. The intelligent dock pier electro-hydraulic control system with mechanical locking function according to claim 4, characterized in that, The integrated control valve group (40) also includes a proportional servo valve (43), a first normally closed solenoid ball valve (441), a second normally closed solenoid ball valve (442), a third normally closed solenoid ball valve (443), a first safety valve (451), and a second safety valve (452). The P port of the first normally closed solenoid ball valve (441) is connected to the P port of the integrated control valve group (40), the A port of the first normally closed solenoid ball valve (441) is connected to the P port of the proportional servo valve (43), the T port of the proportional servo valve (43) is connected to the T port of the integrated control valve group (40), the A port and B port of the proportional servo valve (43) are respectively connected to the P port of the second normally closed solenoid ball valve (442) and the P port of the third normally closed solenoid ball valve (443), and the A port of the second normally closed solenoid ball valve (442) and the A port of the third normally closed solenoid ball valve (443) are respectively connected to the A1 port and B1 port of the integrated control valve group (40). The A port of the second normally closed solenoid ball valve (442) and the A port of the third normally closed solenoid ball valve (443) are also connected to the P port of the first safety valve (451) and the P port of the second safety valve (452), respectively. The T port of the first safety valve (451) and the T port of the second safety valve (452) are connected to the T port of the integrated control valve group (40).

6. The intelligent dock pier electro-hydraulic control system with mechanical locking function according to claim 5, characterized in that, The integrated control valve group (40) also includes a manual directional valve (461), a first one-way throttle valve (462), a first manual ball valve (463), and a second manual ball valve (464). The P port and T port of the manual directional valve (461) are respectively connected to the P port and T port of the integrated control valve group (40). The A port and B port of the manual directional valve (461) are respectively connected to the A1 port and B1 port of the first one-way throttle valve (462). The A2 port and B2 port of the first one-way throttle valve (462) are respectively connected to the inlet port of the first manual ball valve (463) and the inlet port of the second manual ball valve (464). The outlet ports of the first manual ball valve (463) and the second manual ball valve (464) are respectively connected to the B1 port and A1 port of the integrated control valve group (40).

7. The intelligent dock pier electro-hydraulic control system with mechanical locking function according to claim 5, characterized in that, It also includes a PLC control system (60) and a sensor group electrically connected to the PLC control system (60), the sensor group comprising: A first pressure sensor (511), a second pressure sensor (512), a third pressure sensor (513), and a fourth pressure sensor (514) are respectively connected to the A1 port, the B1 port, the A2 port, and the B2 port of the integrated control valve group (40). A displacement sensor (52) is installed outside the hydraulic cylinder (10) to measure the displacement of the hydraulic cylinder (10); A first proximity switch (531), a second proximity switch (532), and a third proximity switch (533) are arranged sequentially from bottom to top and located on one side of the external gear locking nut (21), respectively indicating the locked position, retracted position, and extended position of the external gear locking nut (21).

8. The intelligent dock pier electro-hydraulic control system with mechanical locking function according to claim 7, characterized in that, The PLC control system (60) includes a CPU module (61), an AI module (62), a DI module (63), an AO module (64), and a DO module (65). The AI ​​module (62) is electrically connected to the first pressure sensor (511), the second pressure sensor (512), the third pressure sensor (513), the fourth pressure sensor (514) and the displacement sensor (52), and is used to receive pressure analog signals and displacement analog signals; The DI module (63) is electrically connected to the first proximity switch (531), the second proximity switch (532) and the third proximity switch (533), and is used to receive position status switch signals; The AO module (64) is electrically connected to the proportional relief valve (34) and the proportional servo valve (43) and is used to output current signals to control the pressure and opening degree of the proportional relief valve (34) and the proportional servo valve (43); The DO module (65) is electrically connected to the two-way solenoid valve (35), the first normally closed solenoid ball valve (441), the second normally closed solenoid ball valve (442), the third normally closed solenoid ball valve (443), and the solenoid directional valve (472), and is used to output a switching signal to control its on / off state.

9. A control method for an intelligent dock pier electro-hydraulic control system with mechanical locking function, characterized in that, The control method, applied to the intelligent dock pier electro-hydraulic control system with mechanical locking function according to any one of claims 1 to 8, comprises: S11, start oil supply, control the two-way solenoid valve (35) of the distributed hydraulic oil source (30) to be energized and start the motor hydraulic pump group (32), and adjust the oil supply pressure to the preset value by adjusting the current of the proportional relief valve (34); S12, unlock the hydraulic cylinder (10), control the solenoid directional valve (472) of the integrated control valve group (40) to make the hydraulic motor (23) drive the external gear locking nut (21) through the drive gear (22) to enter the unlocking operation: the external gear locking nut (21) first disengages from the first proximity switch (531), and then gradually moves between the second proximity switch (532) and the third proximity switch (533), and the unlocking operation is completed; S13 enables the proportional servo valve (43) and controls the second normally closed solenoid ball valve (442), the third normally closed solenoid ball valve (443), and the first normally closed solenoid ball valve (441) to be energized, so that the action of the hydraulic cylinder (10) is completely controlled by the proportional servo valve (43). S14, closed-loop position control of hydraulic cylinder (10), PLC control system (60) calculates the current position deviation based on the target position curve information of hydraulic cylinder (10) sent by upper control system through fieldbus and the real-time position feedback of displacement sensor (52), and then calculates the opening command of proportional servo valve (43) based on position control algorithm, and then controls the opening degree of proportional servo valve (43) according to the opening command. The high pressure oil supplied by distributed hydraulic oil source (30) generates driving flow through proportional servo valve (43) to drive hydraulic cylinder (10), so that hydraulic cylinder (10) tracks the target position curve sent by upper control system.

10. The control method of the intelligent dock pier electro-hydraulic control system with mechanical locking function according to claim 9, characterized in that, Also includes: External gear locking nut follow-up control method: As the hydraulic cylinder (10) moves continuously in tracking the target position curve issued by the upper control system, the external gear locking nut (21) follows the movement of the hydraulic cylinder (10) according to the following follow-up control strategy: S2a. During the lifting process of the hydraulic cylinder (10), once the external gear locking nut (21) touches the third proximity switch (533), the solenoid reversing valve (472) is controlled to make the hydraulic motor (23) drive the external gear locking nut (21) through the drive gear (22) to perform locking operation. Once the external gear locking nut (21) touches the second proximity switch (532), the solenoid reversing valve (472) is controlled to make the hydraulic motor (23) stop operating. At the same time, the opening of the second one-way throttle valve (473) is set so that the speed at which the hydraulic motor (23) drives the external gear locking nut (21) to perform locking operation is faster than the lifting speed of the hydraulic cylinder (10). S2b. During the retraction of the hydraulic cylinder (10), once the external gear locking nut (21) touches the second proximity switch (532), the solenoid directional valve (472) is controlled to make the hydraulic motor (23) drive the external gear locking nut (21) through the drive gear (22) to perform the unlocking operation. Once the external gear locking nut (21) touches the third proximity switch (533), the solenoid directional valve (472) is controlled to make the hydraulic motor (23) stop operating. At the same time, the opening of the second one-way throttle valve (473) is set so that the speed at which the hydraulic motor (23) drives the external gear locking nut (21) to perform the unlocking operation is faster than the retraction speed of the hydraulic cylinder (10). and / or Shutdown control methods include: S31, lock the hydraulic cylinder (10), control the solenoid reversing valve (472) to make the hydraulic motor (23) drive the external gear locking nut (21) through the drive gear (22) to perform the locking operation until the external gear locking nut (21) touches the first proximity switch (531), the locking operation is completed, and the hydraulic cylinder (10) is reliably locked in the current stop position; S32, de-energize the second normally closed solenoid ball valve (442), the third normally closed solenoid ball valve (443), and the first normally closed solenoid ball valve (441), and cut off the enable signal of the proportional servo valve (43); S33. Gradually reduce the current of the proportional relief valve (34) to zero, depressurize the distributed hydraulic oil source (30), stop the motor hydraulic pump group (32), and de-energize the two-way solenoid valve (35).

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