Hydraulic system for a jacking machine

Abstract

This invention discloses a hydraulic system for a lifting machine, specifically relating to the field of hydraulic control technology for construction machinery. It includes multiple independent drive nodes, a cluster controller, and interconnected hydraulic pipelines. Each drive node integrates a lifting cylinder, an independent hydraulic power module, and a local controller. The invention utilizes a dynamic adaptive synchronization algorithm run by the cluster controller to dynamically adjust control commands based on the load pressure of each node, achieving high-precision synchronization and active load balancing. By using interconnected hydraulic pipelines, healthy nodes can replenish pressure to the cylinders of faulty nodes and take over the load in case of a failure, realizing decentralized hot standby reconfiguration and flexible degradation of system functions. Furthermore, the system achieves predictive health management through digital twins and micro-motion self-checks, significantly improving synchronization accuracy, system reliability, and intelligent maintenance levels.

Description

Technical Field

[0001] This invention relates to the field of hydraulic control technology for engineering machinery, and more specifically, to the hydraulic system of a jacking machine. Background Technology

[0002] Multi-cylinder synchronous lifting technology is crucial in fields such as the installation of large components, bridge jacking, and maintenance of heavy equipment.

[0003] Traditional jacking systems mostly use centralized pump stations for oil supply, and synchronization is achieved through diversion and collection valves or master-slave proportional valves. This type of solution has inherent drawbacks:

[0004] Long pipelines result in large pressure loss and slow response. A single pump station failure can easily lead to the paralysis of the entire system. Synchronous control relies heavily on position closed loops, which can easily produce false synchronization when the load is uneven. This causes the lifted structure to bear large internal stress, posing a safety hazard.

[0005] In addition, the system maintenance is mostly reactive and has poor fault early warning capabilities.

[0006] Therefore, there is an urgent need for a lifting solution with high reliability, high synchronization accuracy, and intelligent fault tolerance and health management capabilities. In view of this, the present invention provides a hydraulic system for lifting machines. Summary of the Invention

[0007] In order to overcome the above-mentioned defects of the prior art, the present invention provides a hydraulic system for a lifting machine to solve the problems mentioned in the background art.

[0008] To achieve the above objectives, the present invention provides the following technical solution: a hydraulic system for a lifting machine, comprising:

[0009] Multiple independent drive nodes, each drive node including a lifting cylinder and a hydraulic power module integrated into the lifting cylinder;

[0010] The cluster controller connects to the driver nodes via a real-time communication network.

[0011] Each of the drive nodes is equipped with a local sensor for detecting the status of its lifting cylinder and can send the status data to the cluster controller via the network;

[0012] The cluster controller is configured to generate differentiated control commands based on the status data of each drive node and send them to the corresponding drive node to coordinate the synchronous action of all lifting cylinders.

[0013] Hydraulic interconnection pipelines are provided between at least some of the adjacent drive nodes.

[0014] Preferably, the hydraulic power module includes:

[0015] A pump unit, which is independent and dedicated to supplying hydraulic oil to the corresponding lifting cylinder;

[0016] An electro-hydraulic proportional valve is connected between the pump unit and the lifting cylinder to receive control commands and regulate the flow rate entering the lifting cylinder.

[0017] The local controller communicates with the electro-hydraulic proportional valve, local sensors, and cluster controller to achieve local closed-loop control of the drive node.

[0018] Preferably, the pump assembly includes a high-pressure plunger pump driven by a servo motor;

[0019] The system also includes a micro accumulator, which is connected via a one-way valve to the oil line between the outlet of the high-pressure plunger pump and the inlet of the electro-hydraulic proportional valve.

[0020] Preferably, the cluster controller pre-stores a pressure-weight mapping relationship and is configured to perform dynamic adaptive synchronization control, specifically including:

[0021] It receives displacement and load pressure signals from each drive node in real time.

[0022] Based on the load pressure signal and the pressure-weight mapping relationship, the displacement command weight of each drive node is dynamically calculated. For drive nodes whose load pressure exceeds the first threshold, the following weight of their displacement command is reduced.

[0023] Weighted displacement commands are sent to the local controllers of each drive node.

[0024] Preferably, when the load pressure of a certain drive node exceeds a second threshold higher than the first threshold, it is determined to be an abnormal load, and at least one adjacent drive node is instructed to increase the output pressure setting value of its electro-hydraulic proportional valve to share the abnormal load. At the same time, the displacement command weight of the abnormal drive node is reduced accordingly.

[0025] Preferably, it also includes a digital twin prediction module, which pre-stores a performance degradation model of key hydraulic components;

[0026] The local controller is also configured to: drive the hydraulic power module to execute a micro-motion self-test program and collect actual response data to send to the cluster controller when the system is in standby mode;

[0027] The cluster controller compares the actual response data with the predicted values ​​of the performance degradation model to assess the health status of the components and provide early warnings when performance degradation exceeds a threshold.

[0028] Preferably, the micro accumulator is configured to: provide or absorb instantaneous hydraulic oil to compensate for the flow difference when the instantaneous flow demand of a certain driving node changes abruptly during cluster synchronization;

[0029] In addition, when a single drive node fails and the load is taken over by an adjacent node, it provides initial hydraulic locking and buffering power to the lifting cylinder of the failed node.

[0030] Preferably, the cluster controller is further configured to perform decentralized hot standby reassembly, specifically including:

[0031] When a failure is detected in a driver node, that node is immediately marked as offline.

[0032] The control task is redesigned, and at least one adjacent healthy drive node is instructed to partially or completely take over the lifting load borne by the faulty node by adjusting the opening of its electro-hydraulic proportional valve and the output of its pump set.

[0033] Preferably, during the replanning of control tasks, the cluster controller first instructs the healthy drive node that takes over the load to control its electro-hydraulic proportional valve, so that the hydraulic power module of the healthy drive node provides compensating pressure or flow to the lifting cylinder of the faulty node through the oil circuit, so as to achieve a smooth transition of the load.

[0034] The present invention also provides a cluster control method for the hydraulic system of the above-mentioned jacking machine, comprising the following steps:

[0035] Synchronous control steps: The cluster controller acquires the displacement and real-time load pressure data of each drive node, generates differentiated displacement commands based on the dynamic weight algorithm, and sends them to each drive node for execution;

[0036] Health management steps: During system standby intervals, trigger the hydraulic power modules of each drive node to perform micro-motion self-checks, and conduct predictive health status assessments based on the comparison results of the digital twin model;

[0037] Fault-tolerant switching steps: When a fault is detected in a certain drive node, the cluster controller first instructs at least one adjacent healthy drive node to control its electro-hydraulic proportional valve, so that the hydraulic power module of the healthy drive node provides compensating pressure or flow to the lifting cylinder of the faulty node through the oil circuit. Then, the output of the healthy drive node is adjusted to take over the load.

[0038] The technical effects and advantages of this invention are as follows:

[0039] 1. This invention, by adopting a distributed independent drive node architecture and combining a pressure-weight mapping dynamic adaptive synchronization algorithm based on real-time load pressure feedback, achieves a fundamental transformation from traditional single-position closed-loop control to displacement-force composite collaborative control. This enables the system to actively sense the uneven load at each lifting point and dynamically adjust the motion command weights and output pressures of each node. Thus, while ensuring overall synchronization accuracy, it actively balances the forces at each point, effectively overcoming the technical problem that traditional methods easily lead to large internal stresses in the lifted structure when the load is uneven. This greatly improves the safety of lifting operations and adaptability to complex working conditions.

[0040] 2. This invention provides a decentralized hot standby reorganization mechanism. When a single drive node fails, the system can quickly replenish pressure and flow to it through the hydraulic interconnection pipeline from adjacent healthy nodes and dynamically take over its load tasks. This achieves seamless isolation of the failed node and flexible degradation of system functions, rather than overall collapse. It fundamentally solves the reliability bottleneck of traditional centralized pumping stations where a single point failure leads to the paralysis of the entire system, ensuring that critical operations can still be carried out safely and continuously when some units fail.

[0041] 3. By integrating a digital twin prediction module and a micro-motion self-test program, this invention enables the system to automatically perform online detection and evaluation of the performance of key components such as servo motors, hydraulic pumps, and proportional valves during standby intervals. By comparing real-time response data with digital model prediction values, it can identify performance degradation trends in advance and issue warnings. This transforms the maintenance mode from traditional passive repair after a fault or periodic over-maintenance to state-based accurate predictive maintenance, thereby effectively preventing sudden failures, reducing unplanned downtime, and significantly improving the overall availability of the system while reducing long-term maintenance costs. Attached Figure Description

[0042] Figure 1 This is a general system module diagram of the present invention.

[0043] Figure 2 This is a flowchart of the dynamic adaptive synchronization control algorithm of the present invention.

[0044] The attached diagram is labeled as follows: 1. Drive node; 2. Cluster controller; 3. Local sensor; 10. Lifting cylinder; 11. Hydraulic power module; 110. Pump set; 111. Electro-hydraulic proportional valve; 112. Local controller; 1101. High-pressure plunger pump; 4. Micro accumulator; 5. Digital twin prediction module. Detailed Implementation

[0045] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0046] Example 1

[0047] This embodiment provides a hydraulic system for the lifting machine, as shown in the attached diagram. Figure 1 As shown, the system mainly includes four drive nodes 1, a cluster controller 2, and hydraulic interconnection pipelines connecting adjacent drive nodes 1. It should be noted that, for the sake of simplification, four drive nodes 1 are used as an example, but the actual number can be increased, decreased, or expanded as needed.

[0048] Each driver node 1 is a fully functional independent unit, the core of which includes:

[0049] Lifting cylinder 10, an actuator that performs the lifting action;

[0050] Hydraulic power module 11: Integrated next to the lifting cylinder 10, providing it with independent oil supply and control. This module further includes:

[0051] Pump unit 110: It consists of a servo motor driving a high-pressure plunger pump 1101. The pump unit 110 is independent and dedicated to providing hydraulic oil to the corresponding lifting cylinder 10, forming a distributed power source.

[0052] Electro-hydraulic proportional valve 111: Its inlet is connected to the outlet of pump unit 110, and its working port is connected to the rodless chamber of lifting cylinder 10. It is used to receive electrical control signals and continuously and proportionally adjust the flow rate and direction of the oil entering lifting cylinder 10. It is a key component for precise control.

[0053] Miniature accumulator 4: It is connected to the main oil line between the oil outlet of the high-pressure plunger pump 1101 and the oil inlet of the electro-hydraulic proportional valve 111 through a one-way valve. Its main function is to absorb pressure pulsation and replenish when the system needs a large instantaneous flow rate, or to store energy when absorbing shock.

[0054] Local controller 112: can be an embedded PLC or motion controller. It is connected to the driver of electro-hydraulic proportional valve 111 via fieldbus, and also communicates with local sensor group 3 and cluster controller 2. It is responsible for executing instructions from cluster controller 2 and realizing high-speed closed-loop control of the displacement and pressure of lifting cylinder 10 of this node.

[0055] Local sensor 3: includes at least one magnetostrictive displacement sensor installed in the lifting cylinder 10, and a pressure sensor installed in the rodless chamber oil circuit of the lifting cylinder 10;

[0056] The cluster controller 2 can be an industrial computer with real-time control software installed. It communicates with the local controller 112 of all drive nodes 1 through a high-speed real-time industrial Ethernet, such as an EtherCAT network, to perform periodic deterministic and aperiodic data exchange. The core control and management program of the system runs within the cluster controller 2.

[0057] A key improvement is that a hydraulic interconnection pipeline is connected between the working chamber oil circuits of the lifting cylinder 10 of adjacent drive nodes 1. Specifically, the hydraulic interconnection pipeline is connected between the outlet of the electro-hydraulic proportional valve 111 of the two adjacent nodes and the pipe section of the rodless chamber of the lifting cylinder 10. A two-position two-way solenoid directional valve or a small-diameter proportional valve controlled by the electrical signal of the cluster controller 2 is provided on the pipeline to open or close the connection under command, thereby realizing the complementary pressure and flow between adjacent cylinder chambers.

[0058] The principle and working process of this system are mainly reflected in three modes: normal synchronous lifting mode, health prediction management mode, and fault-tolerant reconfiguration mode, as detailed below:

[0059] Normal synchronous lifting and dynamic adaptive coordinated mode

[0060] As attached Figure 2 As shown, when the system performs the synchronization lifting task, cluster controller 2 executes the dynamic adaptive synchronization control algorithm, and the specific process is as follows:

[0061] S1, Cluster Controller 2 sends a unified lifting target displacement command to all drive nodes 1;

[0062] S2. The local controller 112 of each drive node 1 drives the servo motor and electro-hydraulic proportional valve 111 according to the received displacement command to start lifting. At the same time, the three local sensors collect the actual displacement and load pressure data of the oil cylinder in real time.

[0063] S3, Local Controller 112 packages the displacement and pressure data and feeds it back to Cluster Controller 2 via real-time network;

[0064] S4, the core algorithm of cluster controller 2, begins to work. It has a pre-stored pressure-weight mapping relationship, which defines the dynamic adjustment rules between load pressure and displacement command following weight. The algorithm analyzes the pressure signals fed back by each node in real time.

[0065] As one specific implementation method, the mapping relationship can be as follows: Let the load pressure be... The first pressure threshold is The second pressure threshold is , > The weight is ,when ≤ hour, =1, when < ≤ hour, ,in The preset attenuation coefficient is 0 < <1, when > When this occurs, abnormal load handling is triggered;

[0066] S5, Regarding load pressure Not exceeding the preset first threshold The node, its displacement command weight Keep it at 1, meaning strictly follow the target instruction;

[0067] S6, Regarding load pressure Between the first threshold Second threshold The nodes between them indicate that they encounter relatively large resistance, and the algorithm dynamically reduces the weight of their displacement commands based on the mapping relationship. This means that in the next control cycle, the displacement command value received by the node will be slightly lower than the target value, and its ascent rate will be actively slowed down.

[0068] S7, Cluster Controller 2 will assign the target displacement command to the weights of each node. Multiply the values ​​to obtain the differentiated displacement commands and send them to each local controller 112;

[0069] S8 and the local controller 112 adjust their output according to the new instructions to realize the action of the hydraulic cylinder. At this time, the high-pressure node automatically waits, while the low-pressure node continues to lift normally, thereby dynamically balancing the load at each point and avoiding structural stress concentration. This process is repeated until the target position is reached, realizing true adaptive synchronization.

[0070] If the load pressure on a node continues to increase and exceeds a higher second threshold... The cluster controller 2 then determines that the load is abnormal at this point. In addition to continuing to reduce the displacement weight of the abnormal node, it will also instruct one or more adjacent healthy nodes through the hydraulic interconnection pipeline to temporarily increase the output pressure setting of the electro-hydraulic proportional valve 111. This allows high-pressure oil to actively flow to the cylinder of the abnormal node through the interconnection pipeline, providing it with additional support force, thereby achieving active load sharing and ensuring system safety.

[0071] Health Prediction Management:

[0072] During system standby intervals, cluster controller 2 will start a predictive health management program. Its built-in digital twin prediction module 5 stores mathematical models of performance degradation of key components, such as servo motors, piston pumps, and proportional valves.

[0073] Cluster controller 2 instructs a certain drive node 1 to enter micro-motion self-test mode. Local controller 112 will drive the servo motor to run in a specific mode for a short time and quickly open and close the electro-hydraulic proportional valve 111 at a small angle. At the same time, it will collect actual data such as the motor current response, the pump outlet pressure build-up time, and the valve step response time.

[0074] These actual data are uploaded to cluster controller 2 and compared with the ideal predicted values ​​in the digital twin model based on the new state of the components. By analyzing the deviations between real-time data and predicted data in characteristic parameters such as response time, overshoot, and steady-state error, the performance degradation of the pump or valve can be assessed. When the assessed performance degradation exceeds the preset safety threshold, the system will issue an early warning to prompt maintenance personnel to inspect the module, thereby achieving preventive maintenance.

[0075] Fault tolerance and decentralized hot standby reassembly:

[0076] When a critical failure occurs in a drive node 1, such as pump failure or controller power loss, the system initiates a decentralized hot standby reconfiguration process, which includes the following steps:

[0077] S1, Cluster Controller 2 detects a fault in Drive Node 1A through communication timeout or abnormal sensor data;

[0078] S2, Cluster Controller 2 immediately marks node A as offline in the control logic and stops sending commands to it;

[0079] S3, Cluster Controller 2 initiates the reorganization algorithm, re-plans the control tasks, and distributes the load escalating from the faulty node A to one or two adjacent healthy driving nodes 1, such as node B, to take over;

[0080] S4. In order to achieve a smooth load transition and avoid shock, the cluster controller 2 first instructs the healthy node B to adjust its electro-hydraulic proportional valve 111 so that part of the pressure oil output by its pump is slowly injected into the rodless chamber of the lifting cylinder 10 of the faulty node A through the hydraulic interconnection pipeline. During this process, the micro accumulator 4 in the cylinder of the faulty node can provide initial buffering and pressure holding to help stabilize the load.

[0081] S5. After the pressure is compensated and the load is stabilized through the interconnected pipeline, the cluster controller 2 instructs the healthy node B to gradually increase the output of its own pump group 110 and the opening of the electro-hydraulic proportional valve 111, and officially take over and lift up the part of the load shared by the faulty node A.

[0082] S6. The system enters a new stable state, and the remaining healthy nodes continue to work collaboratively under the new control law. The overall lifting force of the system achieves flexible degradation rather than collapse, which greatly ensures the continuity of operations.

[0083] Example 2

[0084] This embodiment provides a cluster control method for the hydraulic system of the jacking machine in Embodiment 1. The software program mainly runs on the cluster controller 2, and the method mainly includes:

[0085] Synchronization control steps: as in S1-S8 of Example 1, to achieve dynamic adaptive synchronization;

[0086] Health management steps: As in Example 1, perform micro-motion self-check and performance evaluation during standby;

[0087] Fault-tolerant switching steps: as shown in S1-S8 of Example 1, to achieve seamless reorganization and load takeover under fault conditions.

[0088] Since the steps of the method have been fully described in the system operation process in Example 1, they will not be repeated here.

[0089] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A hydraulic system for a lifting machine, characterized in that: include: Multiple independent drive nodes (1), each drive node (1) includes a lifting cylinder (10) and a hydraulic power module (11) integrated into the lifting cylinder (10). The cluster controller (2) is connected to the driver node (1) via a real-time communication network; Each of the drive nodes (1) is equipped with a local sensor (3) for detecting the status of its lifting cylinder (10) and can send the status data to the cluster controller (2) via the network. The cluster controller (2) is configured to generate differentiated control commands based on the status data of each drive node (1) and send them to the corresponding drive node (1) to coordinate the synchronous action of all lifting cylinders (10); Hydraulic interconnection pipelines are provided between at least some of the adjacent drive nodes (1).

2. The hydraulic system for the lifting machine according to claim 1, characterized in that: The hydraulic power module (11) includes: Pump assembly (110), which is independent and dedicated to supplying hydraulic oil to the corresponding lifting cylinder (10); An electro-hydraulic proportional valve (111) is connected between the pump unit (110) and the lifting cylinder (10) to receive control commands and regulate the flow rate entering the lifting cylinder (10); The local controller (112) is connected in communication with the electro-hydraulic proportional valve (111), the local sensor (3) and the cluster controller (2) to realize the local closed-loop control of the drive node (1).

3. The hydraulic system for the lifting machine according to claim 2, characterized in that: The pump assembly (110) includes a high-pressure plunger pump (1101) driven by a servo motor. The system also includes a micro accumulator (4), which is connected via a check valve to the oil line between the outlet of the high-pressure plunger pump (1101) and the inlet of the electro-hydraulic proportional valve (111).

4. The hydraulic system for the lifting machine according to claim 3, characterized in that: The cluster controller (2) has a pre-stored pressure-weight mapping relationship and is configured to perform dynamic adaptive synchronization control, specifically including: Real-time reception of displacement signals and load pressure signals from each drive node (1); Based on the load pressure signal and the pressure-weight mapping relationship, the displacement command weight of each drive node (1) is dynamically calculated. For drive nodes (1) whose load pressure exceeds the first threshold, the following weight of their displacement command is reduced. Weighted displacement commands are sent to the local controller (112) of each drive node (1).

5. The hydraulic system for the lifting machine according to claim 4, characterized in that: The cluster controller (2) is also configured to: when the load pressure of a certain drive node (1) exceeds a second threshold higher than the first threshold, determine that the load is abnormal, and instruct at least one adjacent drive node (1) to increase the output pressure setting value of its electro-hydraulic proportional valve (111) to share the abnormal load, and at the same time, reduce the displacement command weight of the abnormal drive node (1) accordingly.

6. The hydraulic system for the lifting machine according to claim 2, characterized in that: It also includes a digital twin prediction module (5), which contains a pre-stored performance degradation model of key hydraulic components; The local controller (112) is also configured to: drive the hydraulic power module (11) to execute a micro-motion self-test program and collect actual response data to send to the cluster controller (2) when the system is in standby mode. The cluster controller (2) compares the actual response data with the predicted values ​​of the performance degradation model to assess the health status of the components and provide early warnings when the performance degradation exceeds the threshold.

7. The hydraulic system for the lifting machine according to claim 3, characterized in that: The micro accumulator (4) is configured to provide or absorb instantaneous hydraulic oil to compensate for the flow difference when the instantaneous flow demand of a certain driving node (1) changes abruptly during cluster synchronization. In addition, when a single drive node (1) fails and the load is taken over by an adjacent node, the initial hydraulic locking and buffering power is provided to the lifting cylinder (10) of the failed node.

8. The hydraulic system for the lifting machine according to claim 2, characterized in that: The cluster controller (2) is further configured to perform decentralized hot standby reassembly, specifically including: When a fault is detected in a certain drive node (1), the node is immediately marked as offline; The control task is replanned, and at least one adjacent healthy drive node (1) is instructed to partially or completely take over the lifting load borne by the faulty node by adjusting the opening of its electro-hydraulic proportional valve (111) and the output of its pump group (110).

9. The hydraulic system for the lifting machine according to claim 8, characterized in that: During the replanning of the control task, the cluster controller (2) first instructs the healthy drive node (1) that takes over the load to control its electro-hydraulic proportional valve (111), so that the hydraulic power module (11) of the healthy drive node (1) provides compensation pressure or flow to the lifting cylinder (10) of the faulty node through the oil circuit, so as to achieve a smooth transition of the load.

10. A cluster control method for the hydraulic system of a jacking machine according to any one of claims 1-9, characterized in that: Includes the following steps: Synchronous control steps: The cluster controller (2) obtains the displacement and real-time load pressure data of each driving node (1), generates differentiated displacement instructions based on the dynamic weight algorithm, and sends them to each driving node (1) for execution; Health management steps: During system standby intervals, trigger the hydraulic power module (11) of each drive node (1) to perform micro-motion self-check, and conduct predictive health status assessment based on the comparison results of the digital twin model; Fault-tolerant switching steps: When a fault is detected in a certain drive node (1), the cluster controller (2) first instructs at least one adjacent healthy drive node (1) to control its electro-hydraulic proportional valve (111) so that the hydraulic power module (11) of the healthy drive node (1) provides compensation pressure or flow to the lifting cylinder (10) of the faulty node through the oil circuit. Then, the output of the healthy drive node (1) is adjusted to take over the load.

Images