Action priority control system and action priority control method

Abstract

The application relates to a priority control system, and discloses an action priority control system and an action priority control method. The action priority control system comprises a plurality of sequentially arranged action links, an oil inlet oil path, a pilot oil inlet oil path, a pilot oil return oil path and a controller which are connected with each other, the action link comprises a main valve connected with an actuator, a control port of the main valve is connected with the pilot oil inlet oil path and the pilot oil return oil path through a pilot valve, a priority control valve is arranged on the oil inlet oil path between adjacent action links, and under a composite action working condition, a valve port opening degree of the priority control valve is controlled by the controller according to pressure signals before and after the priority control valve, so as to control the flow distribution to the action link in the front rank. The application can adapt to the frequent change of the load in actual work, accurately distribute the flow, has good controllability, high work efficiency, small energy consumption and simple structure.

Description

TECHNICAL FIELD

[0001] The present application relates to a priority control system, in particular, to an action priority control system. Furthermore, the present application also relates to an action priority control method. BACKGROUND

[0002] Small excavators are widely used in construction, engineering and other industries, and are often faced with the situation that multiple actuators act simultaneously and the load frequently changes. The coordination of multiple actuators composite action has a significant impact on the working efficiency of the whole machine and even the safety of the driver. The walking, slewing, boom lifting, stick extending, bucket folding and their composite actions of the whole vehicle are realized by the hydraulic control system which reasonably distributes the flow of hydraulic pump oil to each actuator.

[0003] The hydraulic control system of a small excavator usually adopts a load-sensitive system. Theoretically, the flow distribution of the system is independent of the load, but in actual work, the hydraulic oil of the same hydraulic pump is necessarily preferentially supplied to the actuator with smaller load, thereby causing slow or no action of other actuators. In order to improve the composite action performance, a method of increasing a fixed throttle is usually adopted. The fixed throttle is arranged in the oil inlet circuit of the load link with lower load. The throttle does not work in single action to ensure the energy saving of the system circuit. In composite action, the throttle works to improve the action speed of the actuator with larger load, so that the two actuators can coordinate action when the loads are uneven.

[0004] However, the method of improving the composite action performance by arranging a pressure compensation valve and increasing a fixed throttle in the existing load-sensitive system cannot adapt to the frequent changes of the load in actual working conditions, and the fixed throttle causes additional energy loss, and the system energy loss is large. SUMMARY

[0005] The technical problem to be solved by the present application is to provide an action priority control system which can adapt to the frequent changes of the load in actual work to accurately distribute the flow, has good maneuverability, high working efficiency, small energy consumption and simple structure.

[0006] The technical problem to be solved by the present application is to provide an action priority control method which can adapt to the frequent changes of the load in actual work to accurately distribute the flow, has good maneuverability and high working efficiency.

[0007] To address the aforementioned technical problems, this invention provides an action priority control system, comprising multiple sequentially arranged action links, an inlet oil path connecting each action link, a pilot inlet oil path, a pilot return oil path, and a controller. Each action link includes a main valve connected to an actuator. The control port of the main valve is connected to the pilot inlet oil path and the pilot return oil path via a pilot valve. A priority control valve is provided on the inlet oil path between adjacent action links. Under combined action conditions, the controller controls the valve opening of the priority control valve based on the pressure signals before and after the priority control valve, thereby controlling the flow rate distribution to the action link that is ranked first.

[0008] Optionally, the priority control valve includes a priority valve and a proportional valve. The proportional valve includes a first oil port connected to the control port of the priority valve, a second oil port connected to the pilot inlet oil circuit, and a third oil port connected to the pilot return oil circuit.

[0009] Furthermore, the priority control valve also includes a first pressure detection device for detecting the pressure at the inlet of the priority valve and a second pressure detection device for detecting the pressure at the outlet of the priority valve, wherein the first pressure detection device and the second pressure detection device are installed on the inlet oil line.

[0010] Specifically, the proportional valve is a proportional solenoid valve.

[0011] Optionally, each of the aforementioned action sequences includes a first action sequence and a second action sequence. The first action sequence includes a first main valve, a first pilot valve, and a second pilot valve. One control port of the first main valve is connected to the pilot inlet oil circuit and the pilot return oil circuit through the first pilot valve, and the other control port of the first main valve is connected to the pilot inlet oil circuit and the pilot return oil circuit through the second pilot valve. The second action sequence includes a second main valve, a third pilot valve, and a fourth pilot valve. One control port of the second main valve is connected to the pilot inlet oil circuit and the pilot return oil circuit through the third pilot valve, and the other control port of the second main valve is connected to the pilot inlet oil circuit and the pilot return oil circuit through the fourth pilot valve.

[0012] Specifically, the first pilot valve, the second pilot valve, the third pilot valve, and the fourth pilot valve are all proportional solenoid valves.

[0013] Another aspect of the present invention provides an action priority control method, based on any one of the above-described action priority control systems, wherein the action priority control method includes:

[0014] Determine the target flow required for the action sequence that comes first in the sequence;

[0015] When each of the aforementioned action links is in a combined action condition, the pressure signals before and after the priority control valve are acquired to determine the flow rate supplied to the action link that is ranked first. If the flow rate is not equal to the target flow rate, the controller controls the valve opening of the priority control valve to provide the target flow rate to the action link that is ranked first.

[0016] Optionally, before acquiring the pressure signals before and after the priority control valve, the load status of each actuator is acquired. If each of the actions is in a compound action condition and the load of each actuator is equal, the controller does not output a control signal to the priority control valve.

[0017] Furthermore, the pressure difference across each actuator is obtained, and if the pressure difference across each actuator is equal, it is determined that the load of each actuator is equal.

[0018] Optionally, the pressure signals before and after the priority control valve are acquired in real time to determine the flow rate supplied to the action sequence that is prioritized. If the flow rate is equal to the target flow rate, the controller maintains the control signal output to the priority control valve unchanged.

[0019] The beneficial effects of the present invention through the above technical solution are as follows:

[0020] This invention incorporates a priority control valve in the oil inlet line between adjacent action sequences. Based on the detected pressure signals before and after the priority control valve, the flow rate to the action sequence preceding it is determined. If the flow rate to the preceding action sequence does not match its target flow rate, the valve opening of the priority control valve is controlled to provide the target flow rate to the preceding action sequence. Furthermore, the controller can adjust the valve opening of the priority control valve in real time based on the detected pressure signals before and after it to adapt to frequent load changes in actual operating conditions, improve the performance of combined actions, and increase work efficiency and energy utilization. Overall, it is easy to operate and has a simple structure.

[0021] Other features and advantages of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0022] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the following detailed description to explain the invention, but do not constitute a limitation thereof. In the drawings:

[0023] Figure 1 This is a hydraulic schematic diagram of the action priority control system in a specific embodiment of the present invention;

[0024] Figure 2This is a control flowchart of the action priority control method in a specific embodiment of the present invention;

[0025] Figure 3 This is a control block diagram of the action priority control method in a specific embodiment of the present invention.

[0026] Explanation of reference numerals in the attached figures

[0027] 1. Controller 2. Priority control valve

[0028] 21 Priority valve 22 Proportional valve

[0029] 23 First pressure detection device 24 Second pressure detection device

[0030] 3 First Action Link 31 First Main Valve

[0031] 32 First pilot valve 33 Second pilot valve

[0032] 4. Second Action Link 41. Second Main Valve

[0033] 42 Third pilot valve 43 Fourth pilot valve

[0034] 101 Oil Inlet Circuit 102 Pilot Oil Inlet Circuit

[0035] 103 Pilot return oil circuit Detailed Implementation

[0036] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0037] Furthermore, the terms “first,” “second,” and “third” are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as “first,” “second,” or “third” may explicitly or implicitly include one or more of the stated features.

[0038] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "set," "connect," and "install" 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 direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0039] First, it should be noted that those skilled in the art, after understanding the technical concept of the hydraulic connection relationship of this invention, can also make simple substitutions to the oil circuits or valves to achieve the function of the action priority control system of this invention, which also falls within the protection scope of this invention. Related hydraulic components, such as directional valves, hydraulic cylinders, motors, and hydraulic pumps, are well known to those skilled in the art and are commonly used components in existing hydraulic systems. Therefore, these hydraulic components will only be briefly described below, while the focus will be on the original hydraulic connection relationship of the action priority control system of this invention.

[0040] like Figure 1 As shown, the present invention provides an action priority control system, including multiple action links, an oil inlet circuit 101, a pilot oil inlet circuit 102, a pilot return oil circuit 103, and a controller 1. The action links are arranged sequentially. Generally, the positions of the action links are arranged according to their priority. The oil inlet circuit 101 connects to each action link. Each action link includes a main valve, which is connected to the corresponding actuator. The oil inlet circuit 101 connects to each main valve to provide hydraulic oil to the corresponding actuator. The control port of the main valve is connected to the pilot oil inlet circuit 102 and the pilot return oil circuit 103 through a pilot valve. A priority control valve 2 is provided on the oil inlet circuit between adjacent action links. Under compound action conditions, the controller 1 controls the valve opening of the priority control valve 2 according to the pressure signals before and after the priority control valve 2 to control the flow distribution to the action link that is ranked first.

[0041] By installing a priority control valve 2 in the oil inlet line between adjacent action links, when each action link performs a combined action, the flow rate to the action link that is ranked first is determined based on the pressure signals before and after the priority control valve 2. If the flow rate to the action link that is ranked first is not equal to the target flow rate required by the action link that is ranked first, the controller 1 adjusts the valve opening of the priority control valve 2 so that the flow rate allocated to the action link that is ranked first can reach the target flow rate, thus achieving precise flow distribution. The target flow rate can be a specific flow rate value or a flow rate range, thereby improving the performance of combined actions and increasing work efficiency and energy utilization. Moreover, the controller 1 adjusts the valve opening of the priority control valve 2 in real time, which can, to a certain extent, keep the flow rate of the action link that is ranked first at the target flow rate in real time, thereby adapting to frequent load changes in actual working conditions, with good operability and simple structure.

[0042] It should be noted that "a priority control valve 2 is installed on the oil inlet line between adjacent action lines" means that, according to actual needs, the priority control valve 2 can be set before or after a certain action line, or it can be set separately in two adjacent action lines. With reference to the direction of oil flow in the oil inlet line 101, the action line located before the priority control valve 2 has a higher priority than the action line located after it.

[0043] As a specific embodiment of the priority control valve 2, such as Figure 1 As shown, the priority control valve 2 includes a priority valve 21 and a proportional valve 22. The proportional valve 22 includes a first port, a second port, and a third port. The first port of the proportional valve 22 is connected to the control port of the priority valve 21, the second port of the proportional valve 22 is connected to the pilot inlet oil passage 102, and the third port of the proportional valve 22 is connected to the pilot return oil passage 103. Preferably, the proportional valve 22 is a proportional solenoid valve, which can be a three-position two-way valve with three ports, corresponding to the control port of the priority valve 21, the pilot inlet oil passage 102, and the pilot return oil passage 103, respectively. The pilot inlet oil passage 102 is connected to an external oil source through the pilot inlet port Pp, and the pilot return oil passage 103 is connected to an external oil source through the pilot return oil port Dr. The proportional valve 22 connects the pilot inlet oil passage 102 or the pilot return oil passage 103 to the control port of the priority valve 21, controlling the switching of the priority valve 21.

[0044] Furthermore, the priority control valve 2 is also equipped with a first pressure detection device 23 and a second pressure detection device 24. The first pressure detection device 23 and the second pressure detection device 24 are installed on the oil inlet circuit 101. The first pressure detection device 23 is used to detect the pressure at the inlet of the priority valve 21, and the second pressure detection device 24 is used to detect the pressure at the outlet of the priority valve 21. The detected pressures at the inlet and outlet of the priority valve 21 are then fed back to the controller 1, which controls the opening degree of the priority valve 21 based on this pressure information. Preferably, the first pressure detection device 23 and the second pressure detection device 24 are instruments used for pressure detection, such as pressure sensors.

[0045] To facilitate the description of the technical solution of the present invention, the following description uses two sets of action linkages as an example.

[0046] like Figure 1As shown, the action priority control system includes a first action link 3 and a second action link 4. The first action link 3 has a first oil port A1 and a second oil port B1, and is connected to the first actuator through the first oil port A1 and the second oil port B1. The second action link 4 has a third oil port A2 and a fourth oil port B2, and is connected to the second actuator through the third oil port A2 and the fourth oil port B2. Specifically, the first actuation link 3 includes a first main valve 31, a first pilot valve 32, and a second pilot valve 33. One end of the control port of the first main valve 31 is connected to the pilot inlet oil passage 102 and the pilot return oil passage 103 through the first pilot valve 32, and the other end of the control port of the first main valve 31 is connected to the pilot inlet oil passage 102 and the pilot return oil passage 103 through the second pilot valve 33. The second actuation link 4 includes a second main valve 41, a third pilot valve 42, and a fourth pilot valve 43. One end of the control port of the second main valve 41 is connected to the pilot inlet oil passage 102 and the pilot return oil passage 103 through the third pilot valve 42, and the other end of the control port of the second main valve 41 is connected to the pilot inlet oil passage 102 and the pilot return oil passage 103 through the fourth pilot valve 43. The first main valve 31 and the second main valve 41 can be six-position three-way valves. The oil inlet circuit 101 connects the first main valve 31 and the second main valve 41. The oil inlet port P of the oil inlet circuit 101 is connected to the hydraulic pump. The first main valve 31 is connected to the first actuator through the first port A1 and the second port B1. The second main valve 41 is connected to the second actuator through the third port A2 and the fourth port B2. Thus, the oil inlet circuit 101 can supply oil to the first actuator through the first main valve 31 and to the second actuator through the second main valve 41. The first main valve 31 and the second main valve 41 are also connected to the return oil circuit, and return oil is achieved through the return port T of the return oil circuit. Preferably, the first pilot valve 32, the second pilot valve 33, the third pilot valve 42, and the fourth pilot valve 43 are proportional solenoid valves.

[0047] In a specific embodiment of the present invention, taking the typical working condition of a mini excavator—the combined action of full-vehicle rotation and boom lifting—as an example, this working condition accounts for approximately 20% to 25% of the excavator's loading cycle time. Its operational coordination significantly impacts the overall machine efficiency. Especially when the turntable rotates to the loading position, if the boom fails to lift to the unloading height, it poses a risk of collision between the bucket and the transport truck. Under traditional control methods, the phenomenon of the boom failing to lift to the unloading height frequently occurs. By introducing the action priority control system of the present invention, operational coordination can be significantly improved and the probability of collisions reduced. Specifically, when the mini excavator performs a full-bucket lifting operation, this is a combined action consisting of boom lifting and turntable rotation. The first actuator is a hydraulic cylinder for boom lifting, and the second actuator is a hydraulic motor for turntable rotation. The load on the first action linkage 3 is much greater than the load on the second action linkage 4. To avoid collision hazards, the flow demand of the boom must be prioritized during operation. In this case, the first action linkage 3 is the prioritized action linkage. The pressure at the inlet of the priority valve 21 is detected by the first pressure detection device 23, and the pressure at the outlet of the priority valve 21 is detected by the second pressure detection device 24. The target flow rate required by the boom is known. The controller 1 calculates the opening area of ​​the throttling orifice of the priority valve 21 and converts it into a corresponding electrical signal output to the control port of the proportional valve 22, so that the opening area of ​​the throttling orifice of the priority valve 21 continuously decreases. Here, the opening area of ​​the priority valve 21 and the electrical signal are designed to be inversely proportional, that is, the larger the electrical signal output by the controller 1, the smaller the opening area of ​​the priority valve 21. This results in the flow rate allocated to the action link before the priority valve 21 (the priority action link) increasing as needed, and the flow rate allocated to the action link after it decreasing. That is, the flow rate entering the first action link 3 increases, and the flow rate entering the second action link 4 decreases, until the boom is raised to the unloading height at the target speed. Since the pressure values ​​before and after the priority valve 21 change in real time during this process, the control process is dynamic. After unloading is completed, the load on the boom is greatly reduced. At this time, the proportional valve 22 is de-energized and the priority valve 21 returns to its initial position, so that the damping in the oil inlet circuit 101 disappears, realizing the boom descending rapidly and the turntable rotating rapidly to the loading position.

[0048] Specifically, the first action link 3 and the second action link 4 are structurally identical, with the main difference being that the first main valve 31 uses an O-type hydraulic directional valve, while the second main valve 41 uses a Y-type hydraulic directional valve. This addresses the existing hydraulic control systems for small excavators where different action links have different functions of their corresponding directional valves, leading to differences in structural design and assembled parts, and requiring separate compensation valves in each action link, further complicating the structure. In this invention, the actions of each actuator are primarily achieved through programs set in the controller 1. The design of each action link can be unified into two types represented by the first action link 3 and the second action link 4, with essentially identical structural designs and higher parts commonality. By embedding different working programs in the controller 1, different working modes can be achieved without changing the system principle or structural design, resulting in greater flexibility.

[0049] like Figure 1As shown, in a preferred embodiment of the present invention, the action priority control system includes a first action link 3, a second action link 4, an oil inlet circuit 101, a pilot oil inlet circuit 102, a pilot oil return circuit 103, and a controller 1. The oil inlet circuit 101 connects the first action link 3 and the second action link 4. In the hydraulic flow direction in the oil inlet circuit 101, the first action link 3 is arranged in the second action link 4. The first action link 3 includes a first main valve 31, a first pilot valve 32, and a second pilot valve 33. One end of the control port of the first main valve 31 is connected to the pilot oil inlet circuit 103 through the first pilot valve 32. 02 and pilot return oil circuit 103 are respectively connected. The other end control port of the first main valve 31 is connected to the pilot inlet oil circuit 102 and pilot return oil circuit 103 respectively through the second pilot valve 33. The second action link 4 includes a second main valve 41, a third pilot valve 42 and a fourth pilot valve 43. One end control port of the second main valve 41 is connected to the pilot inlet oil circuit 102 and pilot return oil circuit 103 respectively through the third pilot valve 42. The other end control port of the second main valve 41 is connected to the pilot inlet oil circuit 102 and pilot return oil circuit 103 respectively through the fourth pilot valve 43. The first main valve 31 and the second main valve 41 can be six-position three-way valves. The first main valve 31 is connected to the first actuator through the first oil port A1 and the second oil port B1, and the second main valve 41 is connected to the second actuator through the third oil port A2 and the fourth oil port B2. The priority control valve 2 is installed in the oil inlet passage 101 between the first main valve 31 and the second main valve 41. The priority control valve 2 includes a priority valve 21, a proportional valve 22, a first pressure detection device 23, and a second pressure detection device 24. The proportional valve 22 has a first oil port, a second oil port A2, a third oil port B2, and a fourth oil port B2. The first port of the proportional valve 22 is connected to the control port of the priority valve 21, the second port of the proportional valve 22 is connected to the pilot inlet oil passage 102, and the third port of the proportional valve 22 is connected to the pilot return oil passage 103. The priority valve 21, the first pressure detection device 23, and the second pressure detection device 24 are all installed on the inlet oil passage 101. The first pressure detection device 23 is used to detect the pressure at the inlet of the priority valve 21, and the second pressure detection device 24 is used to detect the pressure at the outlet of the priority valve 21.

[0050] The excavator operator sends corresponding control signals via the control handle, which are then processed and converted into electrical signals by the controller 1, acting on the corresponding electromagnetic proportional valves in the action linkage. For example, when the operator sends a signal to raise the hydraulic cylinder via the control handle, the controller 1 outputs an electrical signal acting on the control port of the first pilot valve 32. High-pressure signal oil flows from the pilot inlet Pp through the pilot inlet oil passage 102 to the left control port of the first main valve 31, while low-pressure signal oil flows from the pilot return oil port Dr through the pilot return oil passage 103 to the right control port of the first main valve 31. The left end of the valve core of the first main valve 31 experiences greater force, while the right end experiences less force, causing the valve core to reverse, and the first main valve 31 switches to the left position. Oil enters the rod chamber of the hydraulic cylinder from the inlet P through the working oil port B1, and the oil in the rodless chamber of the hydraulic cylinder flows back to the oil tank through the working oil port A1 and the return oil port T, realizing the hydraulic... The hydraulic cylinder rises, and its speed is related to the magnitude of the electrical signal received by the proportional solenoid valve. This signal magnitude is controlled by the operator via a control handle according to the actual working conditions. Similarly, reversing the operation of the first main valve 31 can achieve the hydraulic cylinder's descent in the first action sequence 3. Likewise, when the fourth pilot valve 43, connected to the right control port of the second main valve 41, is energized, the second main valve 41 switches to the right position, enabling the hydraulic motor to descend or rotate counter-clockwise (reverse rotation). Similarly, reversing the operation of the second main valve 41 can achieve the hydraulic motor's clockwise rotation (forward rotation) in the second action sequence 4. Furthermore, by simultaneously providing electrical signals to the main valves of different action sequences, four different composite actions can be achieved: hydraulic cylinder rising and hydraulic motor forward rotation, hydraulic cylinder rising and hydraulic motor reverse rotation, hydraulic cylinder descending and hydraulic motor forward rotation, and hydraulic cylinder descending and hydraulic motor reverse rotation.

[0051] When the loads of the various actuators are not equal, the priority control valve 2 operates. The priority control valve 2 is essentially a variable area throttling orifice. The flow rate entering the first actuator corresponding to the first action link 3 is equal to the total flow rate entering the oil inlet P minus the flow rate entering the second actuator corresponding to the second action link 4. The flow rate entering the second actuator corresponding to the second action link 4 is equal to the flow rate through the priority control valve 2. The flow rate through the priority control valve 2 is proportional to the pressure difference across the throttling orifice and the opening area. Therefore, to make the flow rate entering the first actuator corresponding to the first action link 3 reach the preset target flow rate, the area opening size of the priority valve 21 throttling orifice can be obtained by detecting the pressure difference across the throttling orifice of the priority valve 21. The specific control process is as follows: The first pressure detection device 23 and the second pressure detection device 24 transmit the pressure signal feedback signal to the controller 1. The controller 1 adjusts the magnitude of the electrical signal acting on the proportional valve 22 through the feedback pressure signal, thereby adjusting the flow rate acting on the left control port of the priority valve 21 through the pilot oil inlet circuit 102. This ultimately changes the size of the throttling port opening of the priority valve 21. The opening area of ​​the priority valve 21 is inversely proportional to the electrical signal, that is, the larger the electrical signal output by the controller 1, the smaller the opening area of ​​the priority valve 21. This causes the flow rate allocated to the action link before the priority valve 21 (the priority action link) to increase as needed, and the flow rate allocated to the action link after it to decrease, until the flow rate value of the priority action link reaches the preset target flow rate.

[0052] based on Figure 1 The action priority control system shown refers to Figure 2 and Figure 3 The action priority control method provided by the present invention will be described below.

[0053] The action priority control method includes the following steps:

[0054] Determine the target flow rate required for the preceding action sequence. Generally, the operating handle signal can be used as the command signal. The command signal determines the target flow rate required for the preceding action sequence. If there is no command signal, it indicates that the actuators are not performing actions, and the control program can be terminated.

[0055] When all actuators are in a combined operating condition, the pressure signals before and after the priority control valve 2 are acquired to determine the flow rate supplied to the actuator that is first in the sequence. If the flow rate of the first actuator is not equal to the target flow rate, the controller 1 controls the opening of the priority control valve 2 to provide the target flow rate to the first actuator. Figure 1Taking the action priority control system shown as an example, the flow rate entering the first actuator corresponding to the first action link 3 is equal to the total flow rate entering the oil inlet P minus the flow rate entering the second actuator corresponding to the second action link 4. The flow rate entering the second actuator corresponding to the second action link 4 is equal to the flow rate through the priority valve 21. The flow rate through the priority valve 21 is proportional to the pressure difference and opening area of ​​its throttling orifice. Therefore, to ensure that the flow rate entering the first actuator corresponding to the first action link 3 reaches the preset target value or target range, the flow rate through the priority valve 21 can be directly determined by detecting the pressure difference before and after the throttling orifice of the priority valve 21, thereby indirectly determining the flow rate supplied to the action link that is ranked first. Based on the target flow rate required by the action link that is ranked first as determined by the operating handle signal, the opening area of ​​the throttling orifice of the priority valve 21 is obtained. The controller 1 controls the throttling orifice of the priority valve 21 to open to the corresponding opening area, so that the flow rate entering the first actuator corresponding to the first action link 3 reaches the preset target value or target range.

[0056] Before activating the priority control valve 2, the load condition needs to be assessed. When the loads of all actuators are equal, it indicates that the flow can be evenly distributed among the action links. Therefore, the controller 1 does not need to output a control signal to the priority control valve 2, rendering it inactive. Generally, the load of each actuator can be determined by detecting the pressure difference across the actuators. Specifically, if the pressure difference across each actuator is equal, the load of each actuator is considered equal. If the pressure difference across each actuator is unequal, the load of each actuator is considered unequal. In this case, the priority control valve 2 needs to activate to prioritize oil supply to the action link that is prioritized, ensuring that the flow supplied to the first-order action link reaches the preset target flow rate.

[0057] Due to the frequent changes in load during actual operation, it is necessary to ensure that the flow rate supplied to the first sequence of actions reaches the corresponding target flow rate in real time. Specifically, this can be achieved by detecting the pressure signals before and after the priority control valve 2 in real time to determine the flow rate supplied to the first sequence of actions. When the flow rate of the first sequence of actions is equal to the target flow rate, the controller 1 maintains the control signal output to the priority control valve 2 unchanged. When the flow rate of the first sequence of actions is not equal to the target flow rate, the controller 1 re-controls the valve opening of the priority control valve 2 to make the flow rate of the first sequence of actions reach the target flow rate again.

[0058] This invention avoids the consequences of excessively large openings in fixed throttling orifices in traditional control systems, resulting in poor maneuverability and significant overflow losses. It also avoids the consequences of excessively small openings in fixed throttling orifices, resulting in low efficiency and significant throttling losses. Compared to traditional control systems that use different designed working links to implement various actuators, in this invention, the actions of each actuator are mainly realized through programs set in controller 1. The design of each action link can be unified into two types represented by the first action link 3 and the second action link 4, with essentially consistent structural designs and higher component commonality. Moreover, by embedding different working programs in controller 1, different operating modes can be achieved without changing the system principle or structural design, resulting in greater flexibility. Using electrical signals to distribute system flow leads to faster signal transmission and more precise control. It should be noted that the controller is a conventional component of a control system. Those skilled in the art, after learning of the technical solution of this invention, can program different working programs in controller 1 to drive the action priority control system and execute the action priority control method of this invention. Therefore, specific examples will not be elaborated here.

[0059] The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the specific details of the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.

[0060] It should also be noted that the various specific technical features described in the above embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the present invention will not describe the various possible combinations separately.

[0061] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed by the present invention.

Claims

1. An action priority control system, characterized in that, The system includes multiple sequentially arranged action links, an oil inlet circuit (101) connecting each action link, a pilot oil inlet circuit (102), a pilot oil return circuit (103), and a controller (1). Each action link includes a main valve connected to an actuator. The control port of the main valve is connected to the pilot oil inlet circuit (102) and the pilot oil return circuit (103) through a pilot valve. A priority control valve (2) is provided on the oil inlet circuit between adjacent action links. Under combined action conditions, the controller (1) controls the valve opening of the priority control valve (2) according to the pressure signals before and after the priority control valve (2) to control the flow rate distribution to the action link that is ranked first.

2. The action priority control system according to claim 1, characterized in that, The priority control valve (2) includes a priority valve (21) and a proportional valve (22). The proportional valve (22) includes a first oil port connected to the control port of the priority valve (21), a second oil port connected to the pilot inlet oil passage (102), and a third oil port connected to the pilot return oil passage (103).

3. The action priority control system according to claim 2, characterized in that, The priority control valve (2) further includes a first pressure detection device (23) for detecting the pressure at the inlet of the priority valve (21) and a second pressure detection device (24) for detecting the pressure at the outlet of the priority valve (21). The first pressure detection device (23) and the second pressure detection device (24) are installed on the oil inlet circuit (101).

4. The action priority control system according to claim 2, characterized in that, The proportional valve (22) is a proportional solenoid valve.

5. The action priority control system according to any one of claims 1 to 4, characterized in that, Each of the aforementioned action sequences includes a first action sequence (3) and a second action sequence (4). The first action sequence (3) includes a first main valve (31), a first pilot valve (32), and a second pilot valve (33). One end of the control port of the first main valve (31) is connected to the pilot inlet oil passage (102) and the pilot return oil passage (103) through the first pilot valve (32). The other end of the control port of the first main valve (31) is connected to the pilot inlet oil passage (102) and the pilot return oil passage (103) through the second pilot valve (33). The return oil circuit (103) is connected; the second action link (4) includes a second main valve (41), a third pilot valve (42) and a fourth pilot valve (43). One end of the control port of the second main valve (41) is connected to the pilot inlet oil circuit (102) and the pilot return oil circuit (103) through the third pilot valve (42), and the other end of the control port of the second main valve (41) is connected to the pilot inlet oil circuit (102) and the pilot return oil circuit (103) through the fourth pilot valve (43).

6. The action priority control system according to claim 5, characterized in that, The first pilot valve (32), the second pilot valve (33), the third pilot valve (42) and the fourth pilot valve (43) are all proportional solenoid valves.

7. A method for prioritizing actions, characterized in that, Based on the action priority control system according to any one of claims 1 to 6, the action priority control method includes: Determine the target flow required for the action sequence that comes first in the sequence; When each of the aforementioned action links is in a combined action condition, the pressure signals before and after the priority control valve (2) are acquired to determine the flow rate supplied to the action link that is ranked first. If the flow rate is not equal to the target flow rate, the controller (1) controls the valve opening of the priority control valve (2) to provide the target flow rate to the action link that is ranked first.

8. The action priority control method according to claim 7, characterized in that, Before acquiring the pressure signals before and after the priority control valve (2), the load status of each actuator is acquired. When each action is in a compound action condition and the load of each actuator is equal, the controller (1) does not output a control signal to the priority control valve (2).

9. The action priority control method according to claim 8, characterized in that, The pressure difference across each actuator is obtained, and if the pressure difference across each actuator is equal, the load of each actuator is determined to be equal.

10. The action priority control method according to claim 7, characterized in that, The pressure signals before and after the priority control valve (2) are acquired in real time to determine the flow rate of the action sequence that is supplied first. When the flow rate is equal to the target flow rate, the controller (1) keeps the control signal output to the priority control valve (2) unchanged.

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