Hydraulic control system for coal mine equipment and hydraulic supports for coal mines

Abstract

The present application relates to the technical field of coal mine hydraulic equipment, and particularly relates to a coal mine equipment hydraulic control system and a coal mine hydraulic support, the coal mine equipment hydraulic control system comprising: a hydraulic actuator and a hydraulic control assembly, the hydraulic control assembly being connected between the hydraulic actuator and a pump station, the flow direction and flow rate of fluid medium on both sides of the hydraulic actuator being adjusted to control the operation of the hydraulic actuator; a detection module configured to detect the state parameters of the hydraulic actuator in real time during system operation; a control module configured to generate a control signal according to the state parameters; and an adjustment module configured to receive the control signal and adjust the flow direction and flow rate of the fluid medium in the hydraulic control assembly according to the control signal. The present application is used to solve the defects of single control mode of hydraulic equipment and difficulty in fine adjustment of dynamic parameters such as hydraulic stroke and speed in the prior art, and realizes stepless and continuous proportional hydraulic equipment adjustment function.

Description

Technical Field

[0001] This invention relates to the field of hydraulic equipment technology in coal mines, and in particular to a hydraulic control system for coal mine equipment and a hydraulic support for coal mines. Background Technology

[0002] Coal mining is a unique and harsh work environment, demanding extremely high reliability and safety from equipment. Hydraulic equipment, due to its high engagement efficiency, powerful output, and precise control, is widely used in coal mining operations; examples include hydraulic supports and hydraulic tunneling machines.

[0003] Traditional hydraulic directional control systems primarily use solenoid valves or directional valve assemblies as core control elements. Their control methods are limited, making it difficult to achieve precise adjustments to dynamic parameters such as hydraulic stroke, speed, and pressure. For example, traditional hydraulic supports can only achieve two states: open and closed. They cannot dynamically adjust the height and speed of the support according to actual conditions, thus limiting their application range and control accuracy.

[0004] With the continuous upgrading of coal mining technology and the increasing requirements for automation, traditional hydraulic reversing control systems can no longer meet the needs of complex applications. Summary of the Invention

[0005] This invention provides a hydraulic control system for coal mine equipment and a hydraulic support for coal mines, which solves the defects of existing hydraulic equipment control methods that are singular and difficult to finely adjust dynamic parameters such as hydraulic stroke and speed, and realizes stepless, continuous and proportional hydraulic equipment adjustment function.

[0006] This invention provides a hydraulic control system for coal mine equipment, comprising: a hydraulic actuator and a hydraulic control component, wherein the hydraulic control component is connected between the hydraulic actuator and a pump station, and controls the operation of the hydraulic actuator by adjusting the flow direction and flow rate of the fluid medium on both sides of the hydraulic actuator; a detection module configured to detect the status parameters of the hydraulic actuator in real time during system operation; a control module configured to generate a control signal based on the status parameters; and an adjustment module configured to receive the control signal and adjust the flow direction and flow rate of the fluid medium in the hydraulic control component according to the control signal.

[0007] According to one embodiment of the present invention, the state parameter includes the actual displacement value of the piston of the hydraulic actuator; the control module includes: a calculation unit configured to perform deviation calculation by means of the actual displacement value and the command displacement value input to the system, so as to calculate the absolute value of the difference between the actual displacement value and the command displacement value as the deviation amount; and a control signal generation unit configured to generate a control signal for adjusting the flow rate of the fluid medium in the hydraulic control component based on the deviation amount.

[0008] According to one embodiment of the present invention, the control module includes a judgment unit; the judgment unit is configured to compare the magnitude of the actual displacement value and the commanded displacement value; when the actual displacement value is less than the commanded displacement value, the control signal includes maintaining the flow direction of the fluid medium in the hydraulic control component unchanged; when the actual displacement value is greater than the commanded displacement value, the control signal includes switching the flow direction of the fluid medium in the hydraulic control component.

[0009] According to one embodiment of the present invention, the regulating module includes a directional valve group and an electro-hydraulic proportional valve disposed in the hydraulic control component; when the hydraulic actuator is started, the directional valve group is opened first, and then the flow rate of the electro-hydraulic proportional valve is gradually increased; when the hydraulic actuator is stopped, the flow rate of the electro-hydraulic proportional valve is gradually decreased first, and then the directional valve group is closed.

[0010] According to one embodiment of the present invention, the pump station is connected to a high-pressure pipeline for outputting a fluid medium and a low-pressure pipeline for recovering the fluid medium. The number of electro-hydraulic proportional valves is one or more, and the electro-hydraulic proportional valves are disposed in any of the following positions: the electro-hydraulic proportional valve is disposed between the reversing valve group and the high-pressure pipeline; the electro-hydraulic proportional valve is disposed between the reversing valve group and the low-pressure pipeline; the electro-hydraulic proportional valve is disposed between the reversing valve group and any inlet / outlet port of the hydraulic actuator.

[0011] The present invention also provides a hydraulic support for a coal mine, comprising: a pushing jack for performing a pushing action of the hydraulic support, the pushing jack being equipped with a displacement sensor for detecting the piston's movement position; a fluid supply mechanism including a pump station, the pump station being connected to a high-pressure pipeline for outputting fluid medium and a low-pressure pipeline for recovering fluid medium; a hydraulic control component disposed between the pushing jack and the fluid supply mechanism, the hydraulic control component including a reversing valve group and an electro-hydraulic proportional valve; and a support controller integrating the hydraulic control system of the coal mine equipment described above, the support controller being respectively connected to the displacement sensor, the reversing valve group, and the electro-hydraulic proportional valve.

[0012] According to one embodiment of the present invention, the reversing valve assembly includes: a shifting main valve disposed between the rodless chamber of the push jack and the high-pressure pipeline; a push-slide main valve disposed between the rod chamber of the push jack and the high-pressure pipeline; a shifting pilot valve electrically connected to the support controller and disposed between the high-pressure pipeline and the shifting main valve, for controlling the movement of the valve core of the shifting main valve; and a push-slide pilot valve electrically connected to the support controller and disposed between the high-pressure pipeline and the push-slide main valve, for controlling the movement of the valve core of the push-slide main valve.

[0013] According to one embodiment of the present invention, the electro-hydraulic proportional valve is disposed between the reversing valve group and the high-pressure pipeline, and the shifting main valve and the push-pull main valve are connected in parallel and connected to the electro-hydraulic proportional valve.

[0014] According to one embodiment of the present invention, a hydraulically controlled check valve is provided between the pipeline connected to the rodless chamber of the push jack and the pipeline connected to the rod chamber of the push jack; when the main valve of the shifting frame is open, the hydraulically controlled check valve is opened by hydraulic pressure, allowing bidirectional flow of fluid medium in the pipeline connected to the rod chamber of the push jack; when the main valve of the shifting frame is closed, the hydraulically controlled check valve is closed, allowing only the fluid medium to enter the rod chamber of the push jack along the pipeline, preventing the fluid medium in the rod chamber from flowing out.

[0015] According to one embodiment of the present invention, the system includes: a first column and a second column, the first column and the second column being connected in parallel to the liquid supply mechanism; a rising column main valve, one side of which is connected to the high-pressure pipeline, and the other side of which is connected to the rodless chamber of the first column and the second column respectively; a falling column main valve, one side of which is connected to the high-pressure pipeline, and the other side of which is connected to the rod chamber of the first column and the second column respectively; a rising column pilot valve, electrically connected to the support controller and disposed between the high-pressure pipeline and the rising column main valve, for controlling the movement of the valve core of the rising column main valve; and a falling column pilot valve, electrically connected to the support controller and disposed between the high-pressure pipeline and the falling column main valve, for controlling the movement of the valve core of the falling column main valve.

[0016] The hydraulic control system and hydraulic support for coal mine equipment provided by this invention introduce an integrated control system comprising a hydraulic actuator, a hydraulic control component, a detection module, a control module, and an adjustment module. The hydraulic control component connects the hydraulic actuator to the pump station, controlling its operation by adjusting the flow direction and flow rate of the fluid medium on both sides of the hydraulic actuator. The detection module monitors the piston movement position in the hydraulic actuator in real time during system operation to obtain the actual displacement value. The control module generates corresponding control signals based on the actual displacement value. The adjustment module receives the control signals and adjusts the flow direction and flow rate of the fluid medium in the hydraulic control component according to the instructions, thereby achieving stepless, continuous, and proportional fine adjustment of the hydraulic equipment. Applying this system to the hydraulic support for coal mines enables dynamic adjustment of its working state through stepless, continuous, and proportional adjustment, thereby enhancing the safety and efficiency of coal mining. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the hydraulic control system for coal mine equipment provided by the present invention.

[0019] Figure 2 This is a schematic diagram illustrating the connection principle of the electro-hydraulic proportional valve in the hydraulic control system for coal mine equipment provided by the present invention.

[0020] Figure 3 This is a schematic diagram of the pipeline connection principle of the hydraulic support for coal mines provided by the present invention.

[0021] Figure label:

[0022] 1. Shifting main valve; 2. Push-slide main valve; 3. Lifting main valve; 4. Lowering main valve; 5. Support controller; 6. Electro-hydraulic proportional valve; 7. Pushing jack; 8. Displacement sensor; 9. First column; 10. Shifting pilot valve; 11. Push-slide pilot valve; 12. Lifting pilot valve; 13. Lowering pilot valve; 14. Pump station; 15. Hydraulic check valve; 16. Second column. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0024] In the description of the embodiments of the present invention, it should be noted that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of the present invention 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. Therefore, they should not be construed as limitations on the embodiments of the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. It should also be noted that in the description of the present invention, unless otherwise explicitly specified and limited, the terms "set," "install," and "connect" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection. Those skilled in the art can understand the specific meaning of the above terms in the present invention according to the specific circumstances.

[0025] The following is combined with Figures 1-3 This invention describes specific embodiments of the hydraulic control system for coal mine equipment and the hydraulic support for coal mines.

[0026] like Figure 1 As shown, this invention provides a hydraulic control system for coal mine equipment, including: a hydraulic actuator and a hydraulic control component. The hydraulic control component is connected between the hydraulic actuator and a pump station 14, and controls the operation of the hydraulic actuator by adjusting the flow direction and flow rate of the fluid medium on both sides of the hydraulic actuator; a detection module configured to detect the status parameters of the hydraulic actuator in real time during system operation; a control module configured to generate control signals based on the status parameters; and an adjustment module configured to receive the control signals and adjust the flow direction and flow rate of the fluid medium in the hydraulic control component according to the control signals. This system can not only realize the position control of the hydraulic actuator, but also calculate the required flow rate in real time through real-time acquisition and analysis of status parameters, and perform precise speed and pressure control accordingly. This allows for specific adjustment of the piston displacement, moving speed, and output torque of the hydraulic actuator, ensuring the efficient operation and safety of the hydraulic equipment in coal mining operations.

[0027] Specifically, the hydraulic actuator, as the core component of the system, directly acts on the object to be controlled (such as a hydraulic support), responsible for executing commands such as adjusting the support height, pushing the slide, and moving the support. The hydraulic control component connects the hydraulic actuator to the pump station 14, flexibly adjusting the actuator's state by regulating the flow direction and volume of hydraulic oil. The detection module monitors the system's operating status in real time, continuously monitoring the position changes of the piston inside the hydraulic actuator and recording actual displacement data. The control module analyzes the status parameters provided by the detection module, calculates the required control signals, and guides the next action of the hydraulic system. The adjustment module receives these signals and adjusts the oil flow in the hydraulic control component accordingly, achieving more precise stepless, continuous, and proportional adjustment of the hydraulic actuator.

[0028] Furthermore, in practical applications, the hydraulic control system for coal mine equipment is suitable for fully mechanized coal mining (longwall mining) equipment systems. For example, precise position control is required during the movement of supports and the pushing of conveyors, which is crucial for maintaining the straightness of the entire longwall face. In addition, the system is also applicable to the attitude control of hydraulic supports, including but not limited to the position control of the balancing hydraulic cylinders, the pressure and position control of the side-support hydraulic cylinders, and the pressure control of the hydraulic support columns. The same principle applies to the control of the advance supports. Moreover, the system can be used for the precise control of the tensioning device of the scraper conveyor, the rotation mechanism of the motor, and even, in the future, when the transmission medium of the coal mining machine is changed from oil to emulsion, the system can be applied to the control of the rocker arm of the coal mining machine. Through these applications, the hydraulic control system for coal mine equipment can significantly improve the efficiency and safety of longwall mining operations.

[0029] According to a hydraulic control system for coal mine equipment based on the present invention, the state parameters preferably include the actual displacement value of the piston of the hydraulic actuator. The control module includes: a calculation unit configured to calculate the deviation between the actual displacement value and the commanded displacement value input to the system, using the absolute value of the difference between the actual displacement value and the commanded displacement value as the deviation; and a control signal generation unit that generates a control signal to adjust the flow rate of the fluid medium in the hydraulic control component based on the deviation. Specifically, the calculation unit first obtains the actual displacement value provided by the detection module and compares it with the preset commanded displacement value of the system, calculating the absolute value of the difference between the two, i.e., the deviation. Subsequently, the control signal generation unit generates a corresponding control signal based on the calculated deviation to adjust the flow rate of the fluid medium in the hydraulic control component, thereby precisely controlling the action of the hydraulic actuator to ensure that it achieves the expected position, speed, or pressure control target. This closed-loop control mechanism ensures the response speed and control accuracy of the hydraulic system, thereby improving the overall performance and reliability of the coal mine equipment.

[0030] It is understood that in other embodiments, the state parameters may include any one or more physical parameters such as the actual displacement value of the piston, hydraulic pressure, and piston movement speed, and the hydraulic control system of the coal mine equipment is operated on this basis.

[0031] Specifically, in schemes based on hydraulic pressure as a state parameter for hydraulic actuators, the hydraulic system's detection module not only monitors the actual displacement of the piston but also measures the internal hydraulic pressure of the actuator in real time. In this case, the control module must handle the deviation between the actual and commanded displacement values, as well as consider changes in hydraulic pressure. If the detected hydraulic pressure is below or above the set safety range, the control module will immediately generate corresponding control commands. The regulating module will adjust the flow direction and flow rate of the hydraulic medium in the hydraulic control components of the hydraulic control circuit to stabilize the hydraulic pressure. This helps prevent equipment damage or operational errors caused by abnormal hydraulic pressure, further ensuring the operational safety and reliability of coal mine equipment.

[0032] In schemes using the piston movement speed of hydraulic actuators as a state parameter, the detection module focuses on real-time monitoring of the piston's movement speed. High-speed data acquisition technology accurately captures changes in piston movement speed under different operating conditions. The control module uses this speed data, combined with the system's preset speed target value, to calculate the speed deviation. Based on the calculation results, the control module issues corresponding control commands to the adjustment module, which then adjusts the flow rate of the hydraulic medium to ensure the piston's movement speed meets the expected requirements. This approach is particularly suitable for scenarios requiring precise control of movement speed, such as when precisely adjusting the height of hydraulic supports or controlling the tension of scraper conveyors, effectively improving work efficiency and operational accuracy while reducing unnecessary energy consumption and wear.

[0033] To ensure the comprehensiveness and flexibility of the hydraulic control system for coal mine equipment, the above implementation plan not only covers control strategies based on hydraulic pressure and piston movement speed as state parameters, but also emphasizes the versatility and adaptability of the system design. Considering the high requirements for positional accuracy in practical applications, we will focus on discussing technical solutions that use the actual displacement value of the piston as the main state parameter. However, this does not preclude the importance and necessity of other state parameters (such as hydraulic pressure and piston movement speed) in specific application scenarios. In fact, multi-parameter integrated control is the key to improving the overall performance of the system. By flexibly utilizing different state parameters, control strategies can be optimized according to specific working environments and task requirements, achieving more precise and efficient hydraulic control effects.

[0034] Furthermore, according to a hydraulic control system for coal mine equipment of the present invention, the control module further includes a judgment unit; the judgment unit is configured to compare the actual displacement value with the commanded displacement value; when the actual displacement value is less than the commanded displacement value, the control signal includes maintaining the flow direction of the fluid medium in the hydraulic control component unchanged; when the actual displacement value is greater than the commanded displacement value, the control signal includes switching the flow direction of the fluid medium in the hydraulic control component. When the system detects a difference between the actual displacement value and the commanded displacement value, the judgment unit automatically performs a comparison. If the actual displacement value is lower than the commanded displacement value, it indicates that the actuator has not yet reached the expected position. At this time, the system will maintain the flow direction of the fluid medium unchanged and continue to push the actuator to move in the target direction; conversely, if the actual displacement value exceeds the commanded displacement value, it indicates that the actuator has exceeded the set position. At this time, the system will change the flow direction of the fluid medium, causing it to move in the opposite direction and return to the correct set position. This design ensures that the hydraulic actuator can move accurately according to the commanded displacement value, improving control accuracy and response speed.

[0035] According to a hydraulic control system for coal mine equipment of the present invention, the regulating module includes a directional valve group and an electro-hydraulic proportional valve 6 disposed in the hydraulic control component. When the hydraulic actuator starts, the directional valve group is opened first, and then the flow rate of the electro-hydraulic proportional valve 6 is gradually increased. When the hydraulic actuator stops, the flow rate of the electro-hydraulic proportional valve 6 is gradually decreased first, and then the directional valve group is closed. When the hydraulic actuator starts to operate, the flow direction of the fluid medium is first determined by opening the directional valve group, and then the flow rate of the electro-hydraulic proportional valve 6 is gradually increased to smoothly accelerate to the required operating speed. When the hydraulic actuator needs to stop, the flow rate of the electro-hydraulic proportional valve 6 is gradually reduced first to decelerate the actuator until it stops completely, and then the directional valve group is closed to cut off the supply of fluid medium. This gradual start-up and stop strategy can not only effectively prevent shocks and wear caused by sudden start-up or stop, but also improve the smoothness of system response, thereby extending the service life of the equipment and improving the overall operational stability.

[0036] like Figure 2As shown, according to a hydraulic control system for coal mine equipment based on the present invention, the pump station 14 is connected to a high-pressure pipeline for outputting fluid medium and a low-pressure pipeline for recovering fluid medium. The number of electro-hydraulic proportional valves 6 is one or more, and the electro-hydraulic proportional valves 6 are positioned in any of the following locations: between the directional valve group and the high-pressure pipeline; between the directional valve group and the low-pressure pipeline; or between the directional valve group and any inlet / outlet port of the hydraulic actuator. This layout allows the system to flexibly configure the position of the electro-hydraulic proportional valves 6 according to actual needs, thereby achieving precise control of the fluid medium flow rate. Whether supplying oil from the high-pressure pipeline to the actuator, returning oil from the actuator to the low-pressure pipeline, or directly controlling the oil flow rate entering the actuator, all can be achieved through the adjustment of the electro-hydraulic proportional valves 6. This not only optimizes the operating efficiency of the hydraulic system but also allows adjustment of the working state of the hydraulic actuator according to the needs of different application scenarios, further improving the system's adaptability and controllability.

[0037] For example, adding an electro-hydraulic proportional valve 6 can be done in four possible locations: on the high-pressure inlet line of the main inlet, between the control chamber of the electro-hydraulic directional valve and the hydraulic actuator, or on the main return line of the electro-hydraulic directional valve. Specifically, these four locations are: the high-pressure inlet line, the inlet between the electro-hydraulic directional valve and the hydraulic actuator, the return line between the electro-hydraulic directional valve and the hydraulic actuator, and the low-pressure return line. Adding the electro-hydraulic proportional valve 6 to any one or more of these four locations is feasible. By installing the electro-hydraulic proportional valve 6 at these critical locations, bidirectional speed regulation and bidirectional precise position or pressure control of the hydraulic actuator can be achieved, thereby improving the flexibility and control accuracy of the entire hydraulic control system. This design provides multiple configuration possibilities, allowing the selection of the most suitable installation scheme based on actual needs.

[0038] The hydraulic support for coal mines provided by the present invention is described below. The hydraulic support for coal mines described below can be referred to in correspondence with the hydraulic control system for coal mine equipment described above.

[0039] like Figure 2 and Figure 3As shown, the present invention also provides a coal mine hydraulic support, comprising: a push jack 7 for performing the pushing action of the hydraulic support, the push jack 7 being provided with a displacement sensor 8 for detecting the piston movement position; a fluid supply mechanism, including a pump station 14, the pump station 14 being connected to a high-pressure pipeline for outputting fluid medium and a low-pressure pipeline for recovering fluid medium; a hydraulic control component, disposed between the push jack 7 and the fluid supply mechanism, the hydraulic control component including a reversing valve group and an electro-hydraulic proportional valve 6; and a support controller 5, integrating the coal mine equipment hydraulic control system of the above embodiment, the support controller 5 being respectively connected to the displacement sensor 8, the reversing valve group and the electro-hydraulic proportional valve 6.

[0040] Specifically, the push jack 7 monitors the position changes of its piston in real time via the displacement sensor 8. This data is transmitted to the support controller 5, which then generates corresponding control signals based on the actual displacement values. The pump station 14 in the fluid supply mechanism provides the necessary fluid medium to the hydraulic actuator through a high-pressure pipeline and recovers the used medium through a low-pressure pipeline. The directional valve group and electro-hydraulic proportional valve 6 in the hydraulic control assembly work together to adjust the flow direction and flow rate of the fluid medium according to the instructions issued by the support controller 5, thereby achieving precise control of the push jack 7. By integrating the hydraulic control system of the coal mining equipment, the support controller 5 can achieve dynamic adjustment of the hydraulic support, ensuring its efficiency and safety in coal mining operations.

[0041] According to a coal mine hydraulic support of the present invention, the reversing valve assembly includes: a shifting main valve 1, disposed between the rodless chamber of the pushing jack 7 and the high-pressure pipeline; a push-slide main valve 2, disposed between the rod chamber of the pushing jack 7 and the high-pressure pipeline; a shifting pilot valve 10, electrically connected to the support controller 5 and disposed between the high-pressure pipeline and the shifting main valve 1, for controlling the movement of the valve core of the shifting main valve 1; and a push-slide pilot valve 11, electrically connected to the support controller 5 and disposed between the high-pressure pipeline and the push-slide main valve 2, for controlling the movement of the valve core of the push-slide main valve 2. Specifically, the shifting main valve 1 and the push-slide main valve 2 respectively control the fluid medium supply to the rodless chamber and the rod chamber of the pushing jack 7, ensuring that the pushing jack 7 can perform push-slide or shifting actions as needed. The shifting pilot valve 10 and the push-flow pilot valve 11 are controlled by the support controller 5 via electronic signals to determine when and how to move the valve core of the corresponding main valve, thereby precisely controlling the flow direction of the fluid medium. This structure not only achieves precise control of the hydraulic support's movements but also improves the system's response speed and control accuracy, enabling the hydraulic support to better adapt to the complex and ever-changing coal mining environment.

[0042] According to a coal mine hydraulic support of the present invention, an electro-hydraulic proportional valve 6 is preferably disposed between the directional valve group and the high-pressure pipeline, and the shifting main valve 1 and the push-pull main valve 2 are connected in parallel to the electro-hydraulic proportional valve 6. In this case, the electro-hydraulic proportional valve 6 is mainly used to regulate the flow rate of the fluid medium entering the hydraulic actuator. Specifically, when the shifting action is required, the electro-hydraulic proportional valve 6 regulates the flow rate of the fluid medium entering the shifting main valve 1 from the high-pressure pipeline, while the push-pull main valve 2 is responsible for returning the fluid medium in the hydraulic actuator to the low-pressure pipeline. Conversely, when the push-pull action is required, the electro-hydraulic proportional valve 6 regulates the flow rate of the fluid medium entering the push-pull main valve 2, while the shifting main valve 1 is responsible for the fluid return.

[0043] According to a preferred embodiment of the coal mine hydraulic support of the present invention, during the support relocation operation, the electromagnet of the relocation pilot valve 10 is energized, and high-pressure liquid enters the pilot control chamber of the relocation main valve 1 through the relocation pilot valve 10, thereby causing the relocation main valve 1 to switch. At this time, the high-pressure liquid output from the pump station 14 passes through the electro-hydraulic proportional valve 6 and then enters the rodless chamber of the push jack 7 through the relocation main valve 1, while the liquid in the rod chamber of the push jack 7 returns to the low-pressure pipeline through the push-pull main valve 2, thus forming a relocation liquid inlet proportional throttling speed regulation system.

[0044] To control the moving speed, the opening of the electro-hydraulic proportional valve 6 is adjusted by the support controller 5, thereby controlling the flow rate into the main moving valve 1. The larger the opening of the electro-hydraulic proportional valve 6, the greater the flow rate into the main moving valve 1, and the faster the moving speed. When approaching the designated position, the opening of the electro-hydraulic proportional valve 6 is gradually reduced, decreasing the flow rate into the main moving valve 1 and thus reducing the moving speed. Once the moving position reaches the commanded position, the opening of the electro-hydraulic proportional valve 6 is closed, and the electromagnet of the moving pilot valve 10 is de-energized, closing the main moving valve 1 and completing the moving action. Because the opening of the electro-hydraulic proportional valve 6 is related to the real-time piston position detected by the pushing jack 7, closed-loop feedback control of displacement is achieved, which greatly improves the accuracy of the moving position and helps to align multiple sets of coal mine hydraulic supports in a near-straight line.

[0045] After the coal mine hydraulic support completes its shifting and column raising, the push-conveyor operation can be performed. Similarly, the electromagnet of the push-conveyor pilot valve 11 is energized, and high-pressure liquid enters the pilot control chamber of the push-conveyor main valve 2 through the push-conveyor pilot valve 11, causing the push-conveyor main valve 2 to switch. At this time, the high-pressure liquid output from the pump station 14 passes through the electro-hydraulic proportional valve 6, and then enters the rod chamber of the push-conveyor jack 7 through the push-conveyor main valve 2. Meanwhile, the liquid in the rodless chamber of the push-conveyor jack 7 returns to the low-pressure pipeline through the shifting main valve 1, forming a push-conveyor liquid inlet proportional throttling speed control system.

[0046] The electro-hydraulic proportional valve 6 can also be positioned on the pipeline after the main valve 1 of the moving frame and before the rodless chamber of the pushing jack 7, thus enabling proportional speed control for both frame movement and conveyor pushing. For example, it forms a proportional speed control system for the inlet liquid during frame movement and a throttling speed control system for the return liquid during conveyor pushing. Alternatively, the electro-hydraulic proportional valve 6 can be positioned on the pipeline between the main valve 2 of the conveyor pushing and the hydraulically controlled check valve 15 of the pushing jack 7, forming a proportional speed control system for the return liquid during frame movement and a proportional speed control system for the inlet liquid during conveyor pushing.

[0047] Regardless of its position, the electro-hydraulic proportional valve 6 can be in either normally open or normally closed state initially. A normally open state means that the electro-hydraulic proportional valve 6 is at its maximum opening by default, allowing high-pressure fluid to immediately enter one chamber of the push-jack 7 when the shifting main valve 1 or the push-slide main valve 2 opens. If the electro-hydraulic proportional valve 6 is normally closed, its main valve port is closed by default, and whether high-pressure fluid can enter one chamber of the push-jack 7 depends on the timing of its opening. Preferably, opening the push-slide main valve 2 or the shifting main valve 1 first, followed by the electro-hydraulic proportional valve 6, effectively reduces hydraulic shock. When the push-jack 7 reaches the designated position, closing the electro-hydraulic proportional valve 6 first, followed by the push-slide main valve 2 or the shifting main valve 1, also reduces hydraulic shock, providing soft-start and soft-close characteristics for a low-impact, stable control strategy.

[0048] According to a coal mine hydraulic support of the present invention, a hydraulically controlled check valve 15 is provided between the pipeline connecting the rodless chamber of the moving jack 7 and the pipeline connecting the rod chamber of the moving jack 7. When the main valve 1 of the support is open, the hydraulically controlled check valve 15 is opened by hydraulic pressure, allowing bidirectional flow of fluid medium in the pipeline connected to the rod chamber of the moving jack 7. When the main valve 1 of the support is closed, the hydraulically controlled check valve 15 is closed, allowing fluid medium to enter the rod chamber of the moving jack 7 along the pipeline, preventing fluid medium in the rod chamber from flowing out. When the main valve 1 of the support is open, the hydraulically controlled check valve 15 allows bidirectional flow of fluid medium in the pipeline connected to the rod chamber of the moving jack 7, ensuring that the hydraulic actuator can operate smoothly. When the main valve 1 of the moving support is closed, the hydraulic check valve 15 becomes closed, allowing fluid to enter the rod chamber of the moving jack 7 only in a specific direction, while preventing backflow of fluid within that chamber. This ensures the stability of the hydraulic system and the normal operation of the actuator. This design guarantees the flexibility of the hydraulic support during moving operations and provides a reliable locking mechanism when a fixed position is required, enhancing the system's safety and control precision.

[0049] According to the present invention, a coal mine hydraulic support includes: a first column 9 and a second column 16, the first column 9 and the second column 16 being connected in parallel to a fluid supply mechanism; a lifting main valve 3, one side of which is connected to a high-pressure pipeline, and the other side of which is connected to the rodless chambers of the first column 9 and the second column 16 respectively; a lowering main valve 4, one side of which is connected to a high-pressure pipeline, and the other side of which is connected to the rod chambers of the first column 9 and the second column 16 respectively; a lifting pilot valve 12, electrically connected to a support controller 5 and disposed between the high-pressure pipeline and the lifting main valve 3, for controlling the movement of the valve core of the lifting main valve 3; and a lowering pilot valve 13, electrically connected to the support controller 5 and disposed between the high-pressure pipeline and the lowering main valve 4, for controlling the movement of the valve core of the lowering main valve 4.

[0050] Specifically, the first column 9 and the second column 16 are connected in parallel to the liquid supply mechanism, allowing for simultaneous column raising or lowering operations. One side of the column raising main valve 3 is connected to a high-pressure pipeline, and the other side is connected to the rodless chambers of the first column 9 and the second column 16, respectively. When column raising is required, the electromagnet of the column raising pilot valve 12 is energized, and high-pressure liquid enters the pilot control chamber of the column raising main valve 3 through the column raising pilot valve 12, causing the column raising main valve 3 to switch direction. The high-pressure liquid then flows into the rodless chambers of the first column 9 and the second column 16, pushing the columns to rise synchronously.

[0051] One side of the main lowering valve 4 is also connected to a high-pressure pipeline, while the other side is connected to the rod chambers of the first column 9 and the second column 16, respectively. When the column needs to be lowered, the electromagnet of the lowering pilot valve 13 is energized, and the high-pressure liquid enters the pilot control chamber of the lowering main valve 4 through the lowering pilot valve 13, causing the lowering main valve 4 to switch. The high-pressure liquid flows into the rod chambers of the first column 9 and the second column 16, causing the columns to descend synchronously.

[0052] By controlling the column raising pilot valve 12 and the column lowering pilot valve 13, the support controller 5 can realize the synchronous raising and lowering control of the columns, ensuring that the first column 9 and the second column 16 move in unison. This not only improves the coordination of the hydraulic support during the column raising and lowering process, but also enhances the overall stability and reliability of the system.

[0053] In order to achieve the required interlocking between the actions of the support, in a preferred embodiment, a hydraulic control check valve 15 is respectively installed between the lower chamber of the lifting column of the first column 9 and the second column 16, the piston rod chamber of the pushing jack 7 and the outlet of the corresponding main valve. The control port of the hydraulic control check valve 15 is connected to another chamber of the corresponding hydraulic actuator.

[0054] like Figure 3As shown, in the case of a single rising main valve 3 and a falling main valve 4, when the main valve rises, the electromagnet of the rising pilot valve 12 is energized, and the high-pressure liquid enters the pilot control chamber of the rising main valve 3 through the rising pilot valve 12, thereby causing the rising main valve 3 to switch. At this time, the high-pressure liquid enters the lower rising chamber of the first column 9 and the second column 16 through the hydraulic control check valve 15 of the first column 9 and the hydraulic control check valve 15 of the second column 16, respectively, while the liquid in the upper falling chamber of the first column 9 and the second column 16 returns to the low-pressure pipeline through the falling main valve 4.

[0055] Similarly, during column lowering, the electromagnet of the column lowering pilot valve 13 is energized, and high-pressure liquid enters the pilot control chamber of the column lowering main valve 4 through the column lowering pilot valve 13, thereby causing the column lowering main valve 4 to switch. At this time, high-pressure liquid enters the upper chamber of the column lowering of the first column 9 and the second column 16. Under the pressure of the high-pressure liquid, the hydraulic control check valve 15 of the first column 9 and the hydraulic control check valve 15 of the second column 16 open under the action of the high-pressure liquid at their control ports. The liquid in the lower chamber of the column rising of the first column 9 and the lower chamber of the column rising of the second column 16 returns to the low-pressure pipeline through the hydraulic control check valve 15 and the column rising main valve 3.

[0056] Understandably, in order to increase the speed of column raising and lowering, multiple column raising main valves 3 and column lowering main valves 4 can be set to increase the liquid supply flow rate, thereby achieving rapid column raising and lowering.

[0057] According to a preferred embodiment of the coal mine equipment hydraulic control system and the coal mine hydraulic support of the present invention, taking the system configuration where the electro-hydraulic proportional valve 6 is located before the shifting main valve 1 and the push-flow main valve 2 as an example, the input is the displacement command of the push-moving jack 7. The displacement sensor 8 uploads the position information of the push-moving jack 7 detected in real time to the support controller 5 and performs deviation calculation. The calculated deviation information has two main functions: first, it is used to determine the sign and absolute value of the position deviation, i.e., the threshold judgment function; second, it serves as the input signal for the closed-loop control of the electro-hydraulic proportional valve 6. Based on the deviation signal, the control signal magnitude of the electro-hydraulic proportional valve 6 is calculated, thereby controlling the flow rate entering the push-moving jack 7.

[0058] Taking the frame-shifting action as an example, initially, because the actual displacement of the pushing jack 7 is much smaller than the commanded displacement, the deviation displacement signal is positive. At this time, the support controller 5 outputs a 1 (digital quantity) to the frame-shifting pilot valve 10, indicating that the frame-shifting pilot valve 10 is open, and simultaneously outputs a 0 (digital quantity) to the push-slide pilot valve 11, indicating that the push-slide pilot valve 11 is closed. In addition, the position deviation is calculated by the support controller 5 (such as a PID controller) and then outputs an analog control quantity to the electro-hydraulic proportional valve 6 to adjust the opening of the electro-hydraulic proportional valve 6 in real time. That is to say, the larger the position deviation, the larger the opening of the electro-hydraulic proportional valve 6. As the pushing jack 7 gradually approaches the commanded position, the deviation signal calculated by the support controller 5 gradually decreases, and the analog control quantity output to the electro-hydraulic proportional valve 6 also gradually decreases. The valve opening of the proportional valve gradually closes until the error is zero, at which point the valve opening is completely closed.

[0059] If the push jack 7 overshoots during the frame movement due to load inertia, it means that the position deviation signal is negative. At this time, the support controller 5 outputs 0 (digital quantity) to the frame movement pilot valve 10, closing the frame movement pilot valve 10, and simultaneously outputs 1 (digital quantity) to the push slide pilot valve 11, opening the push slide pilot valve 11. Meanwhile, the electro-hydraulic proportional valve 6 remains open, thus realizing the reversal of the push jack 7, causing the push jack 7 to move back towards the target command.

[0060] In summary, the deviation is used to control the flow rate; the larger the absolute value of the deviation, the larger the valve opening and the larger the output flow rate. It does not concern itself with the direction of movement of the push jack 7. The threshold judgment, on the other hand, controls the direction of movement of the push jack 7, i.e., the opening and closing status of the main valve 1 and the main valve 2, without concerning itself with the speed of movement of the push jack 7.

[0061] It's also important to note that, theoretically, the direction can be determined simply by the sign of the position deviation signal. However, in practice, if the absolute value of the calculated position deviation signal is very small, i.e., within a certain threshold range, it can be assumed that the actual position of the jack 7 is equal to the commanded position, meaning the deviation is considered zero, and control of the shifting main valve 1 and the pushing main valve 2 is no longer required. Therefore, by setting the aforementioned threshold range, unnecessary control actions can be reduced.

[0062] Furthermore, when starting the push jack 7 (including during extension and retraction), the main inlet valve can be opened first, followed by controlling the electro-hydraulic proportional valve 6 to open. Since the valve opening of the electro-hydraulic proportional valve 6 is gradual, pressure surges are less likely to occur, resulting in a smoother start-up. When the push jack 7 is about to stop (including during extension and retraction), the electro-hydraulic directional valve can be closed first, and the corresponding main inlet valve can be closed after it has come to a stable stop. This effectively avoids pressure surges caused by the on / off valve directly controlling the push jack 7 at the moment of opening and closing, as well as overshoot during stopping. It is understandable that the main valve and the electro-hydraulic proportional valve 6 can also be controlled simultaneously; due to the short response time of the pilot valve, this combination also provides a certain degree of low-impact effect.

[0063] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "method," "specific method," or "some methods," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or method is included in at least one embodiment or method of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or method. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or methods. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or methods described in this specification, as well as the features of different embodiments or methods.

[0064] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention 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 of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A hydraulic control system for coal mining equipment, characterized in that, The hydraulic actuator and the hydraulic control assembly are connected between the hydraulic actuator and the pump station (14), and the flow direction and flow rate of the fluid medium on both sides of the hydraulic actuator are adjusted to control the operation of the hydraulic actuator. The detection module is configured to detect the state parameters of the hydraulic actuator in real time during system operation. The control module is configured to generate a control signal according to the state parameters. The adjustment module is configured to receive the control signal and adjust the flow direction and flow rate of the fluid medium in the hydraulic control assembly according to the control signal. The state parameters include the actual displacement value of the piston of the hydraulic actuator. The control module includes a calculation unit configured to calculate the absolute value of the difference between the actual displacement value and the command displacement value of the input system as a deviation amount by performing deviation calculation on the actual displacement value and the command displacement value; and a control signal generation unit configured to generate a control signal for adjusting the flow rate of the fluid medium in the hydraulic control assembly according to the deviation amount. The control module includes a judgment unit configured to compare the actual displacement value and the command displacement value. In the case where the actual displacement value is less than the command displacement value, the control signal includes maintaining the flow direction of the fluid medium in the hydraulic control assembly unchanged; and in the case where the actual displacement value is greater than the command displacement value, the control signal includes switching the flow direction of the fluid medium in the hydraulic control assembly. The adjustment module includes a reversing valve group and an electro-hydraulic proportional valve (6) arranged in the hydraulic control assembly.

2. The hydraulic control system for coal mining equipment according to claim 1, characterized in that, When the hydraulic actuator is started, the reversing valve group is first opened, and then the flow rate of the electro-hydraulic proportional valve (6) is adjusted to gradually increase. When the hydraulic actuator is stopped, the flow rate of the electro-hydraulic proportional valve (6) is first adjusted to gradually decrease, and then the reversing valve group is closed. The pump station (14) is connected with a high-pressure pipeline for outputting the fluid medium and a low-pressure pipeline for recovering the fluid medium, and the number of the electro-hydraulic proportional valve (6) is one or more.

3. The hydraulic control system for coal mining equipment according to claim 2, characterized in that, The electro-hydraulic proportional valve (6) is arranged between the reversing valve group and the high-pressure pipeline. The electro-hydraulic proportional valve (6) is arranged between the reversing valve group and the low-pressure pipeline. The electro-hydraulic proportional valve (6) is arranged between the reversing valve group and any inlet or outlet of the hydraulic actuator. The push-jack (7) is arranged with a displacement sensor (8) for detecting the moving position of the piston.

4. A hydraulic support for coal mines, characterised in that, The liquid supply mechanism includes a pump station (14) connected with a high-pressure pipeline for outputting the fluid medium and a low-pressure pipeline for recovering the fluid medium. The hydraulic control assembly is arranged between the push-jack (7) and the liquid supply mechanism, and includes a reversing valve group and an electro-hydraulic proportional valve (6). ​ ​ The support controller (5) is integrated with the hydraulic control system of the coal mine equipment in any one of claims 1-3, and is connected to the displacement sensor (8), the reversing valve group and the electro-hydraulic proportional valve (6) respectively.

5. The hydraulic coal mine support of claim 4, wherein, The reversing valve group comprises: The support controller (5) is integrated with the hydraulic control system of the coal mine equipment in any one of claims 1-3, and is connected to the displacement sensor (8), the reversing valve group and the electro-hydraulic proportional valve (6) respectively. The support controller (5) is integrated with the hydraulic control system of the coal mine equipment in any one of claims 1-3, and is connected to the displacement sensor (8), the reversing valve group and the electro-hydraulic proportional valve (6) respectively. The support controller (5) is integrated with the hydraulic control system of the coal mine equipment in any one of claims 1-3, and is connected to the displacement sensor (8), the reversing valve group and the electro-hydraulic proportional valve (6) respectively. The electro-hydraulic proportional valve (6) is arranged between the reversing valve group and the high-pressure pipeline, and the support controller (5) is electrically connected to the displacement sensor (8), the reversing valve group and the electro-hydraulic proportional valve (6).

6. The hydraulic coal mine support of claim 5, wherein, The pipeline connected to the rodless cavity of the push-moving jack (7) and the pipeline connected to the rod cavity of the push-moving jack (7) are provided with a hydraulic control check valve (15).

7. The hydraulic coal mine support of claim 6, wherein, When the support controller (5) is in the first state, the hydraulic control check valve (15) is opened under the influence of the hydraulic pressure, and the fluid medium on the pipeline connected to the rod cavity of the push-moving jack (7) is allowed to flow bidirectionally. When the support controller (5) is in the second state, the hydraulic control check valve (15) is closed, and the fluid medium is only allowed to flow into the rod cavity of the push-moving jack (7) along the pipeline, and the fluid medium in the rod cavity is prevented from flowing out. The support controller (5) is integrated with the hydraulic control system of the coal mine equipment in any one of claims 1-3, and is connected to the displacement sensor (8), the reversing valve group and the electro-hydraulic proportional valve (6) respectively.

8. The hydraulic coal mine support of any one of claims 4-7, wherein, The reversing valve group comprises: The support controller (5) is integrated with the hydraulic control system of the coal mine equipment in any one of claims 1-3, and is connected to the displacement sensor (8), the reversing valve group and the electro-hydraulic proportional valve (6) respectively. The support controller (5) is integrated with the hydraulic control system of the coal mine equipment in any one of claims 1-3, and is connected to the displacement sensor (8), the reversing valve group and the electro-hydraulic proportional valve (6) respectively. The support controller (5) is integrated with the hydraulic control system of the coal mine equipment in any one of claims 1-3, and is connected to the displacement sensor (8), the reversing valve group and the electro-hydraulic proportional valve (6) respectively. The support controller (5) is integrated with the hydraulic control system of the coal mine equipment in any one of claims 1-3, and is connected to the displacement sensor (8), the reversing valve group and the electro-hydraulic proportional valve (6) respectively. ​

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