Design method of hydraulic system of engineering machinery and hydraulic system of engineering machinery

Abstract

The application discloses an engineering machinery hydraulic system design method and an engineering machinery hydraulic system. The engineering machinery hydraulic system design method comprises the following steps: determining the number of actuators according to the functions of engineering machinery; classifying the actuators according to different functions realized by the actuators; determining main modes and main actuators according to the function characteristics of the actuators; determining power mechanisms according to the working characteristics of the main actuators; determining a preliminary hydraulic system comprising the main actuators; integrating and simplifying the preliminary hydraulic system according to the working characteristics of the main actuators to form a simplified hydraulic system; adding secondary actuators to the simplified hydraulic system; and adding auxiliary elements to the simplified hydraulic system. The engineering machinery hydraulic system design method can design an engineering machinery hydraulic system capable of realizing various complex works.

Description

Technical Field

[0001] This invention relates to the field of hydraulic technology, and in particular to a design method for a hydraulic system of engineering machinery and a hydraulic system for engineering machinery. Background Technology

[0002] Tracked heavy-duty screening stations are mobile screening stations with a wide range of applications and strong screening capacity. They can meet the screening needs of large-particle raw materials and are widely used in primary and secondary screening. These devices can operate independently in remote locations and require a diesel engine to drive the hydraulic system for all operations.

[0003] Tracked heavy-duty screening plants need to perform various tasks such as feeding, screening, and conveying materials. The movement is relatively complex, and the design of its hydraulic system is also relatively complex. Summary of the Invention

[0004] The purpose of this invention is to provide a design method for hydraulic systems of engineering machinery that can perform a variety of complex tasks, as well as a hydraulic system for engineering machinery.

[0005] This invention provides a design method for a hydraulic system of engineering machinery, comprising:

[0006] The number of actuators is determined based on the function of the construction machinery;

[0007] The actuators are classified according to the different functions they perform;

[0008] The main mode and main actuator are determined based on the functional characteristics of the actuator.

[0009] The power mechanism is determined based on the working characteristics of the main actuator;

[0010] A preliminary hydraulic system including the aforementioned main actuator was determined;

[0011] Based on the working characteristics of the main actuators, the initial hydraulic system is integrated and simplified to form a simplified hydraulic system;

[0012] A secondary actuator is added to the simplified hydraulic system; and

[0013] Auxiliary components are added to the simplified hydraulic system.

[0014] In one embodiment, in the step of forming a simplified hydraulic system, actuators with the same load and speed are connected in series, and actuators with inversely proportional loads are connected in parallel; a flow divider valve is installed in the oil circuit of the corresponding actuator depending on whether speed regulation is required; and a check valve is installed in the oil circuit of the corresponding actuator depending on whether reverse rotation is required.

[0015] In one embodiment, in the step of adding auxiliary components to the simplified hydraulic system, safety shut-off valves are respectively installed on the oil lines of the main actuators; the safety shut-off valves include a variable damper, a first valve, a second valve, a pressure port, a working port, and a return port. The variable damper includes an inlet port and an outlet port. The inlet port is connected to the pressure port. The second valve is connected between the outlet port and the working port of the variable damper. The second valve is used to connect the outlet port of the variable damper to the working port or to the return port. The first valve is used to connect the control terminal of the second valve to the pressure port or to the return port. The two control terminals of the first valve are respectively connected to the inlet port and the outlet port of the variable damper to switch states according to the pressure of the inlet port and the outlet port of the variable damper.

[0016] In one embodiment, the second valve includes a fourth port, a fifth port, and a sixth port. The fourth port is connected to the outlet of the variable damping valve, the fifth port is connected to the return port, and the sixth port is connected to the working port. The second valve also includes a third position and a fourth position. In the third position, the fourth port and the sixth port are connected, and in the fourth position, the fifth port and the sixth port are connected.

[0017] In one embodiment, the actuator includes a feeding motor, a first-layer motor, a second-layer motor, a screening motor, a transfer motor, a third-layer motor, a left-travel motor, a right-travel motor, and multiple hydraulic cylinders. In the step of classifying the actuators according to their different functions, the feeding motor, the first-layer motor, the second-layer motor, the screening motor, the transfer motor, and the third-layer motor are classified as working mode actuators, the left-travel motor and the right-travel motor are classified as traveling actuators, and the hydraulic cylinders are classified as auxiliary action actuators. In the step of determining the main mode and the main actuators according to their functional characteristics, the main mode is determined to be the working mode, and the feeding motor, the first-layer motor, the second-layer motor, the screening motor, the transfer motor, and the third-layer motor are the main actuators.

[0018] In one embodiment, in the step of determining the initial hydraulic system, multiple oil supply pumps are set up to supply oil to the feeding motor, the first-layer motor, the second-layer motor, the screening motor, the intermediate motor, and the third-layer motor respectively. Each of the oil supply pumps is connected to an oil tank, and a connection is set between the oil tank and the feeding motor, the first-layer motor, the second-layer motor, the screening motor, the intermediate motor, and the third-layer motor, thus forming the initial hydraulic system.

[0019] In one embodiment, in the step of forming the simplified hydraulic system, the intermediate motor and the three-layer motor are connected in series, and the first-layer motor and the second-layer motor are connected in parallel. A flow divider valve is provided in the oil lines corresponding to the feeding motor, the first-layer motor, the second-layer motor, and the screening motor. A check valve is provided in the oil lines corresponding to the first-layer motor, the second-layer motor, and the third-layer motor. A first main valve is provided in the oil line of the feeding motor. A second main valve is provided in the oil lines of the first-layer motor and the second-layer motor. A third main valve is provided in the oil line of the screening motor. A fourth main valve is provided in the oil lines of the intermediate motor and the third-layer motor.

[0020] In one embodiment, in the step of adding secondary actuators to the simplified hydraulic system, the left travel motor, the right travel motor, and the cylinder are added to the simplified hydraulic system; when adding auxiliary components to the simplified hydraulic system, a hydraulic lock is installed on the oil line where the cylinder is located; a radiator and a filter are installed on the return oil line; travel control valves are installed on the oil lines of the left travel motor and the right travel motor; and remote shut-off valves are respectively installed on the oil lines of the feed motor, the first-layer motor, and the second-layer motor.

[0021] This invention also provides a hydraulic system for engineering machinery designed using the above-described hydraulic system design method, comprising a feed motor, a first-layer motor, a second-layer motor, a screening motor, a transfer motor, a third-layer motor, a first main oil circuit, a second main oil circuit, a third main oil circuit, a fourth main oil circuit, a left travel motor, a right travel motor, and a cylinder. The first main oil circuit is sequentially provided with a first main valve, a remote shut-off valve, a flow divider valve, and the feed motor. The first main oil circuit also includes the left travel motor and the right travel motor connected to the first main valve. The second main oil circuit is sequentially provided with a second main valve, a remote shut-off valve, a flow divider valve, a check valve, and the first-layer motor and the second-layer motor connected in parallel. The left travel motor and the right travel motor are also connected to the second main valve. The third main oil circuit is sequentially provided with a third main valve, a flow divider valve, and the screening motor. The fourth main oil circuit is sequentially provided with a fourth main valve, a check valve, the transfer motor, a flow divider valve, a check valve, and the third-layer motor. The first main oil circuit also includes a cylinder connected in parallel with the feed motor.

[0022] In one embodiment, a first safety shut-off valve is further provided between the first main valve and the feed motor; a second safety shut-off valve is further provided between the second main valve and the first-layer motor; a third safety shut-off valve is further provided between the second main valve and the second-layer motor; a fourth safety shut-off valve is further provided between the third main valve and the screening motor; and a fifth safety shut-off valve is further provided between the fourth main valve and the transfer motor. Each of the first, second, third, fourth, and fifth safety shut-off valves includes a variable damping element, a first valve, a second valve, a pressure port, a working port, and a return oil port. The variable damper includes an oil inlet and an oil outlet. The oil inlet is connected to the pressure oil port. The second valve is connected between the oil outlet and the working oil port of the variable damper. The second valve is used to connect the oil outlet and the working oil port or the working oil port and the return oil port of the variable damper. The first valve is used to connect the control terminal of the second valve to the pressure oil port or the control terminal of the second valve to the return oil port. The two control terminals of the first valve are respectively connected to the oil inlet and the oil outlet of the variable damper to switch states according to the pressure of the oil inlet and the oil outlet of the variable damper.

[0023] In the embodiments of the present invention, the hydraulic system design method for engineering machinery of the present invention can be used to design hydraulic systems for engineering machinery that can perform a variety of complex tasks. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of a heavy-duty screening station.

[0025] Figure 2 This is a flowchart illustrating a design method for a hydraulic system of engineering machinery according to an embodiment of the present invention.

[0026] Figure 3 for Figure 2 The diagram shows the initial hydraulic system structure as determined in the hydraulic system design method for engineering machinery.

[0027] Figure 4 for Figure 2 The diagram shows a simplified hydraulic system structure determined in the hydraulic system design method for engineering machinery.

[0028] Figure 5 This is a simplified schematic diagram of the hydraulic system after adding secondary actuators and auxiliary components in the hydraulic system design method for engineering machinery shown.

[0029] Figure 6 for Figure 5 A simplified schematic diagram of the safety control valve structure in a hydraulic system.

[0030] Figure 7 for Figure 5 Detailed structural diagrams of some components of the simplified hydraulic system.

[0031] Figure 8 for Figure 7 The diagram shows the oil flow when the transfer motor or three-layer motor of a simplified hydraulic system fails.

[0032] Figure 9 for Figure 7 The diagram shows a simplified hydraulic system with a single-layer motor failure, illustrating the oil flow.

[0033] Figure 10 for Figure 7 The diagram shows the oil flow in a simplified hydraulic system when the two-stage motor fails.

[0034] Figure 11 for Figure 7 The diagram shows a simplified schematic of the oil flow when the screening motor of a hydraulic system fails.

[0035] Figure 12 for Figure 7 The diagram shows a simplified schematic of the oil flow when the feed motor of a hydraulic system fails. Detailed Implementation

[0036] To further illustrate the technical methods and effects of the present invention in order to achieve the intended purpose, the specific implementation methods, structure, features and effects of the present invention will be described in detail below with reference to the accompanying drawings and embodiments.

[0037] Please refer to Figure 1 A heavy-duty screening station includes a feeding conveyor A, a vibrating screen B, a single-layer conveyor C, a double-layer conveyor D, a transfer conveyor E, and a triple-layer conveyor F. The feeding conveyor A transports material to the vibrating screen B, which has two built-in screens to classify the material, which then flows into the single-layer conveyor C, the double-layer conveyor D, and the transfer conveyor E. The rotating conveyor E then transports the material to the triple-layer conveyor F, resulting in three different material specifications. The heavy-duty screening station also includes a shaped track G to enable it to move. Furthermore, the station includes belt folding and belt angle adjustment functions.

[0038] Please refer to Figure 2 An embodiment of the present invention provides a design method for a hydraulic system of engineering machinery, comprising the following steps:

[0039] S11, Determine the number of actuators based on the function of the construction machinery.

[0040] S13. Classify the actuators according to the different functions they perform.

[0041] S15. Determine the main mode and main implementing agency based on the functional characteristics of the implementing agency.

[0042] S17, Determine the power mechanism based on the working characteristics of the main actuator.

[0043] S19 defines the initial version of the hydraulic system, including the main actuators.

[0044] S21, based on the working characteristics of the main actuators, integrates and simplifies the initial hydraulic system to form a simplified hydraulic system.

[0045] S23, adding a secondary actuator to a simplified hydraulic system.

[0046] S25, which incorporates auxiliary components into a simplified hydraulic system.

[0047] The hydraulic system design method for engineering machinery using the embodiments of the present invention can design hydraulic systems for engineering machinery that can perform a variety of complex tasks.

[0048] The following explanation uses the hydraulic system design method of engineering machinery to design a hydraulic system for heavy-duty screening stations as an example.

[0049] In this embodiment, in step S11, the actuators include a feeding motor 71, a first-layer motor 73, a second-layer motor 75, a screening motor 77, a transfer motor 79, a third-layer motor 80, a left-walking motor 61, a right-walking motor 62, and multiple hydraulic cylinders 63, to respectively realize the functions of feeding, material conveying, material vibrating screening, walking, belt folding, and belt angle adjustment. It can be understood that the number of actuators can be adjusted according to the number of functions required by the heavy-duty screening station. For example, when only two specifications of material need to be separated, one conveying motor can be reduced.

[0050] In this embodiment, in step S13, the feeding motor 71, the first-layer motor 73, the second-layer motor 75, the screening motor 77, the transfer motor 79, and the third-layer motor 80 are classified as working mode actuators, the left travel motor 61 and the right travel motor 62 are classified as travel actuators, and the hydraulic cylinder 63 is classified as an auxiliary action actuator.

[0051] In this embodiment, in step S15, the heavy-duty screening station includes a material screening working mode, a walking mode for movement, and a hydraulic cylinder actuation mode, with the working mode being the primary mode. Movement, belt folding, and angle adjustment are short-term and intermittent, only performed when needed. The material screening working mode is performed by the heavy-duty screening station for extended periods, therefore it is the primary mode. In step S15, the feeding motor 71, the first-layer motor 73, the second-layer motor 75, the screening motor 77, the intermediate motor 79, and the third-layer motor 80 are also identified as the main actuators.

[0052] In this embodiment, in step S17, since the speed and pressure of the actuator in the working mode tend to be stable, the power element is determined to be a gear pump, and the system pressure is determined to be less than 25MPa.

[0053] In this embodiment, in step S19, please refer to... Figure 3 Multiple oil supply pumps 65 are set up to supply oil to the feed motor 71, the first-layer motor 73, the second-layer motor 75, the screening motor 77, the intermediate motor 79, and the third-layer motor 80 respectively. Each oil supply pump 65 is connected to an oil tank, and a connection is set between the oil tank and the feed motor 71, the first-layer motor 73, the second-layer motor 75, the screening motor 77, the intermediate motor 79, and the third-layer motor 80, thus forming a preliminary hydraulic system. The actuators of the preliminary hydraulic system only include the actuators that realize the main mode.

[0054] In this embodiment, in step S21, please refer to... Figure 4 Actuators with the same load and speed are connected in series, while actuators with inversely proportional loads are connected in parallel. In step S21, it is also determined whether to install a flow divider valve 66 in the oil circuit of the corresponding actuator based on whether speed regulation is required, and whether to install a check valve 67 in the oil circuit of the corresponding actuator based on whether reverse rotation needs to be prevented.

[0055] Specifically, in this embodiment, since the transfer belt and the third-layer conveyor belt convey the same material, they have the same load and speed; therefore, the transfer motor 79 and the third-layer motor 80 are connected in series. Since the material load capacity of the first-layer conveyor belt and the second-layer conveyor belt is inversely proportional, the first-layer motor 73 and the second-layer motor 75 are connected in parallel. Because each conveyor belt requires adjustable speed, a flow divider valve 66 is installed in the hydraulic circuits of the corresponding feed motor 71, first-layer motor 73, second-layer motor 75, and screening motor 77. Considering that material may remain on the first-layer, second-layer, and third-layer conveyor belts during shutdown, and that reverse belt rotation could lead to material accumulation, a check valve 67 is installed in the hydraulic circuits corresponding to the first-layer motor 73, second-layer motor 75, and third-layer motor 80. A first main valve 101 is installed in the oil circuit of the feeding motor 71, a second main valve 102 is installed in the oil circuit of the first-layer motor 73 and the second-layer motor 75, a third main valve 103 is installed in the oil circuit of the screening motor 77, and a fourth main valve 104 is installed in the oil circuit of the intermediate motor 79 and the third-layer motor 80.

[0056] In this embodiment, in step S23, please refer to... Figure 5 The left travel motor 61, the right travel motor 62, and the hydraulic cylinder 63 are added to the simplified hydraulic system. Specifically, the left travel motor 61 and the right travel motor 62 are connected to the hydraulic circuits of the feed motor 71, the first-layer motor 73, and the second-layer motor 75, and the hydraulic cylinder 63 is connected to the hydraulic circuit of the feed motor 71.

[0057] In this embodiment, in step S25, a hydraulic lock 68 is installed on the oil line of the hydraulic cylinder 63; a radiator and a filter are installed on the return oil line; a travel control valve 69 is installed on the oil lines of the left travel motor 61 and the right travel motor 62; and a remote shut-off valve 70 is installed on the oil lines of the feed motor 71, the first-layer motor 73, and the second-layer motor 75, respectively.

[0058] Specifically, cylinder 63 needs to extend continuously and maintain pressure inside. Therefore, a hydraulic lock is installed in the oil circuit where cylinder 63 is located to prevent the cylinder from failing to maintain pressure due to internal leakage of the front cylinder valve. Cylinder 63 is mostly used to support or pull an actuator. When this type of cylinder retracts or extends, it is subjected to gravity throughout the entire process. Using a silencer plug at the oil inlet corresponding to this action can reduce piping and joints, thus optimizing costs. The first main valve 101, through the movement of its valve core, supplies oil to the travel control valve 69 and the feeding motor 71, respectively, and the feeding motor drives the feeder to work; the second main valve 102, through the movement of its valve core, supplies oil to the travel control valve 69, the first-layer motor 73, and the second-layer motor 75, respectively, the first-layer motor 73 drives the first-layer conveyor belt to work, and the second-layer motor 75 drives the second-layer conveyor belt to work; the third main valve 103, through the movement of its valve core, controls the screening motor 77, and the screening motor 77 drives the vibrating screen to work; the fourth main valve 104, through the movement of its valve core, controls the intermediate transfer motor 79, the third-layer motor 80, and the hydraulic cylinder control valve 105 to work, the intermediate transfer motor 79 drives the intermediate transfer conveyor belt to work, the third-layer motor 80 drives the third-layer conveyor belt to work, and the hydraulic cylinder control valve 105 controls the extension and retraction of the hydraulic cylinder; the travel control valve 69 controls the forward, backward, and turning movements of the equipment in the travel mode. In the operating mode, the diverter valve 66 determines the speed of the subsequent mechanism; the check valve 67 ensures that the oil flowing through it can only flow in one direction, thus affecting the unidirectional operation of the subsequent mechanism. When the equipment stops (e.g., emergency stop), there may be material in some mechanisms. Under the influence of gravity, the material generates friction on the mechanism, which ultimately acts on the motor, causing it to reverse, potentially leading to material accumulation or jamming; the remote shut-off valve 70, in the operating mode, moves its internal valve core when an external electrical signal is input, stopping the feeder and the first and second belts. When only the remote shut-off valve of the feed motor oil circuit receives an electrical signal, it can be stopped remotely or locally. The equipment feeding system (mostly used for remote operation) can be stopped after the remaining material inside the equipment has been processed. Alternatively, feeding can be stopped remotely when the vibrating screen approaches or exceeds its overload capacity. When the remote shut-off valve of the feeding motor's oil circuit receives an energizing signal, and the equipment has processed the remaining material inside, another remote shut-off valve receives an energizing signal, allowing for remote screen box cleaning. The radiator operates to maintain the hydraulic system at its permissible temperature. The filter filters all hydraulic oil after operation, ensuring the cleanliness of the entire hydraulic system. It is equipped with a check valve and a signal transmitter to prevent blockages and provide alarm functions. Hydraulic cylinders 63 are mostly outrigger cylinders. These cylinders need to be continuously extended by the equipment and require pressure to be maintained inside the cylinder. Therefore, they are equipped with hydraulic locks to prevent the cylinder from failing to maintain pressure due to internal leakage of the front cylinder valve. Cylinders such as 13 are mostly used to support or pull a certain actuator. When these cylinders retract or extend, they are subjected to gravity throughout the entire process. A silencer plug is used at the oil inlet corresponding to this action to reduce pipelines and joints and optimize costs.When the equipment is stopped, the valve cores of the first main valve 101, the second main valve 102, the third main valve 103, and the fourth main valve 104 are in the neutral position; the valve cores of the first main valve 101, the second main valve 102, the third main valve 103, and the fourth main valve 104 are in the lower position, in the working mode; the valve cores of the first main valve 101 and the second main valve 102 are in the upper position, and the valve cores of the third main valve 103 and the fourth main valve 104 are in the neutral position, in the walking mode; the valve cores of the first main valve 101, the second main valve 102, and the third main valve 103 are in the neutral position, and the valve core of the fourth main valve 104 is in the upper position, in the hydraulic cylinder actuation mode. An auxiliary oil tank can be installed inside the main oil tank, dividing the hydraulic oil in the main tank into two areas. The hydraulic oil in the main area can only enter the auxiliary oil tank area through the filter. The reason for setting up an auxiliary oil tank is that heavy-duty screening stations and other equipment have many oil suction points. If each point is equipped with a separate oil suction filter, it will take up a lot of space. If only one oil suction filter is installed, the internal space of the oil tank will be limited. This solution can concentrate the oil suction points, reduce space occupation, and increase the utilization rate of the oil suction filter. The hydraulic cylinder control valves can be freely matched and changed according to the selection and actual layout of the equipment.

[0059] Specifically, in step S25, safety shut-off valves may be installed on the oil lines of the feeding motor 71, the first-layer motor 73, the second-layer motor 75, the screening motor 77, and the transfer motor 79.

[0060] Please refer to Figure 6 The safety shut-off valve includes a variable damper 11, a first valve 13, a second valve 15, a pressure port 17, a working port 19, and a return port 21. The variable damper 11 includes an inlet and an outlet. The inlet is connected to the pressure port 17. The second valve 15 is connected between the outlet and the working port 19 of the variable damper 11, and is used to connect the outlet of the variable damper 11 to the working port 19 or the working port 19 to the return port 21. The first valve 13 is used to connect the control terminal of the second valve 15 to the pressure port 17 or the control terminal of the second valve 15 to the return port 21. The two control terminals of the first valve 13 are respectively connected to the inlet and outlet of the variable damper 11 to switch states according to the pressure at the inlet and outlet of the variable damper 11. In this way, the state of the second valve can be switched under the action of the variable damping and the first valve, thereby cutting off the circuit and relieving pressure on the motor and other actuators when abnormal situations occur, such as system malfunctions or the motor and other actuators no longer working, ensuring system safety. Moreover, it does not require a complete electrical system, has low cost, fast response speed, only takes effect when the actuator is overloaded, has high accuracy, and avoids misjudgment.

[0061] In this embodiment, the variable damper 11 can be a variable throttle valve. The set pressure difference between the inlet and outlet of the variable damper 11 can be ΔP, and the magnitude of the set pressure difference ΔP is related to the opening area A of the throttle valve. Specifically, Where ρ is the fluid (hydraulic oil) density, Q is the flow rate through the variable damper when connected in the hydraulic circuit, and C... d The flow coefficient can be taken as 0.60-0.61 based on experience. The smaller the opening area A, the larger the set pressure difference ΔP of the variable damper 11.

[0062] In this embodiment, the first valve 13 includes a first oil port 131, a second oil port 132, and a third oil port 133. The first oil port 131 is connected to the pressure oil port 17, the second oil port 132 is connected to the return oil port 21, and the third oil port 133 is connected to the control terminal of the second valve 15. The first valve 13 includes a first position and a second position. In the first position, the first oil port 131 and the third oil port 133 are connected. In the second position, the second oil port 132 and the third oil port 133 are connected.

[0063] Specifically, the first valve 13 includes a spring cavity, which is located at the control end of the first valve 13 connected to the oil outlet of the variable damper 11. The setting parameter F of the spring in the spring cavity of the first valve 13 is... x1 Should meet Where S1 is the area of ​​the fluid acting on the valve core of the first valve 13, and ΔP is the set pressure difference of the variable damper 11. The valve core displacement X1 of the first valve 13 is: Among them, P x When connected in the hydraulic circuit, the working pressure of the actuator is k1, the spring coefficient of the spring chamber of the first valve 13, and X1 is the valve core displacement of the first valve 13 (taking the direction of overcoming the spring force as the positive direction).

[0064] In this embodiment, the second valve 15 includes a fourth oil port 151, a fifth oil port 152, and a sixth oil port 153. The fourth oil port 151 is connected to the oil outlet of the variable damper 11, the fifth oil port 152 is connected to the oil return port 21, and the sixth oil port 153 is connected to the working oil port 19. The second valve 15 includes a third position and a fourth position. In the third position, the fourth oil port 151 and the sixth oil port 153 are connected, and in the fourth position, the fifth oil port 152 and the sixth oil port 153 are connected.

[0065] Specifically, the second valve 15 includes a spring cavity located at the end opposite to the control terminal of the second valve 15. The setting parameter F of the spring in the spring cavity of the second valve 15 is... x2 Should meet Where S2 is the area of ​​the fluid acting on the valve core of the second valve 15, and P is the set pressure of the relief valve in the hydraulic circuit when connected to the hydraulic circuit in the engineering machinery hydraulic system design method, that is, the safety set pressure of the pressure port 17. The valve core displacement X2 of the second valve 15 is: Wherein, k2 is the spring constant of the spring cavity of the second valve 15, and X2 is the valve core displacement of the second valve 15 (taking the direction of overcoming the spring force as the positive direction).

[0066] When the actuator malfunctions, the response time t of the entire hydraulic system design method for engineering machinery satisfies the following formula:

[0067] Where K is the elastic bulk modulus of the fluid, which is almost customizable, and ΔP t Let V be the pressure difference between the inlet and outlet of the variable damper 11 at time t, starting from the time of the fault. Let V be the volume of oil between the pressure port 17 and the actuator. Therefore, when the hydraulic system design method for engineering machinery is applied to the system, the smaller A is, the smaller ΔP is, and the shorter the time; when A is constant, ΔP... t =ΔP-F X1 The design method for the hydraulic system of engineering machinery comes into play at time S1, and at this time F X1 The closer S1 is to ΔP, the shorter the time.

[0068] It is understood that when using the above-mentioned hydraulic system design method for engineering machinery, the number and type of actuators for engineering machinery other than heavy-duty screening stations can be set as needed, and the number and type of other auxiliary components can also be set as needed, and are not limited to... Figure 5 The actuators and auxiliary components shown are illustrated.

[0069] This invention also provides a hydraulic system for engineering machinery designed using the above-described hydraulic system design method. Please refer to... Figure 5 and Figure 7One embodiment of the hydraulic system for engineering machinery includes a feeding motor 71, a first-layer motor 73, a second-layer motor 75, a screening motor 77, a transfer motor 79, a third-layer motor 80, a first safety shut-off valve 81, a second safety shut-off valve 82, a third safety shut-off valve 83, a fourth safety shut-off valve 84, a fifth safety shut-off valve 85, a first hydraulic control directional valve 87, a second hydraulic control directional valve 89, a first main oil circuit 91, a second main oil circuit 92, a third main oil circuit 93, and a fourth main oil circuit 94. The first safety shut-off valve 81, the second safety shut-off valve 82, the third safety shut-off valve 83, the fourth safety shut-off valve 84, and the fifth safety shut-off valve 85 all adopt the aforementioned safety shut-off valves. The first hydraulic directional valve 87, the first safety shut-off valve 81, and the feed motor 71 are sequentially arranged on the first main oil circuit 91. The inlet of the first hydraulic directional valve 87 is connected to the pressure oil circuit, and the outlet of the first hydraulic directional valve 87 is connected to the pressure oil port 17 of the first safety shut-off valve 81. The working oil port 19 of the first safety shut-off valve 81 is connected to the feed motor 71. The first-layer motor 73 and the second-layer motor 75 are connected in parallel on the second main oil circuit 92. The pressure oil ports 17 of the second safety shut-off valve 82 and the third safety shut-off valve 83 are respectively connected to the pressure oil circuit. The working oil port 19 of the second safety shut-off valve 82 is connected to the first-layer motor 73, and the working oil port 19 of the third safety shut-off valve 83 is connected to the second-layer motor 75. The second hydraulic directional valve 89, the fourth safety shut-off valve 84, and the screening motor 77 are sequentially arranged on the third main oil circuit 93. The inlet of the second hydraulic directional valve 89 is connected to the pressure oil circuit, and the outlet of the second hydraulic directional valve 89 is connected to the pressure oil port 17 of the fourth safety shut-off valve 84. The working oil port 19 of the fourth safety shut-off valve 84 is connected to the screening motor 77. The fifth safety shut-off valve 85, the intermediate motor 79, and the three-layer motor 80 are sequentially arranged on the fourth main oil circuit 94. The pressure oil port 17 of the fifth safety shut-off valve 85 is connected to the pressure oil circuit, and the working oil port 19 of the fifth safety shut-off valve 85 is connected to the intermediate motor 79. The first hydraulic directional valve 87 has two states: connecting or disconnecting the first main oil circuit 91. The control terminal of the first hydraulic directional valve 87 is connected to the control terminal of the second valve 15 of the second safety shut-off valve 82, the third safety shut-off valve 83, the fourth safety shut-off valve 84, and the fifth safety shut-off valve 85, so as to switch the state according to the pressure of the control terminal of the second valve 15 of at least one of the second safety shut-off valves 82, 83, 84, and 85. The second hydraulic directional valve 89 has two states: connecting or disconnecting the third main oil circuit 93. The control terminal of the second hydraulic directional valve 89 is connected to the control terminal of the second valve 15 of the first safety shut-off valve 82, 83, 84, and 85, so as to switch the state according to the pressure of the control terminal of the second valve 15 of at least one of the second safety shut-off valves 82, 83, 84, and 85.

[0070] In this embodiment, the hydraulic system of the engineering machinery further includes a first shuttle valve 97, a second shuttle valve 98, and a third shuttle valve 99. The two input ports of the first shuttle valve 97 are respectively connected to the control terminal of the second valve 15 of the fifth safety shut-off valve 85 and the output port of the third shuttle valve 99. The two input ports of the second shuttle valve 98 are respectively connected to the control terminal of the second valve 15 of the fourth safety shut-off valve 84 and the output port of the first shuttle valve 97. The output port of the second shuttle valve 98 is connected to the control terminal of the first hydraulically controlled directional valve 87. The two input ports of the third shuttle valve 99 are respectively connected to the control terminals of the second valve 15 of the second safety shut-off valve 82 and the second valve 15 of the third safety shut-off valve 83. Thus, if any one of the control terminals of the second valve 15 of the second safety shut-off valve 82, the third safety shut-off valve 83, and the fifth safety shut-off valve 85 has a higher pressure, the second hydraulic directional valve 89 will be switched, thus disconnecting the third main oil circuit 93; if any one of the control terminals of the second valve 15 of the second safety shut-off valve 82, the third safety shut-off valve 83, the fourth safety shut-off valve 84, and the fifth safety shut-off valve 85 has a higher pressure, the first hydraulic directional valve 87 will be switched, thus disconnecting the first main oil circuit 91.

[0071] In this embodiment, the hydraulic system of the construction machinery also includes a first main valve 101, a second main valve 102, a third main valve 103, and a fourth main valve 104 respectively connected to the first main oil circuit 91, the second main oil circuit 92, the third main oil circuit 93, and the fourth main oil circuit 94. The first main valve 101, the second main valve 102, the third main valve 103, and the fourth main valve 104 are respectively used to control whether to supply high-pressure oil to the first main oil circuit 91, the second main oil circuit 92, the third main oil circuit 93, and the fourth main oil circuit 94.

[0072] Specifically, in this embodiment, the feeding motor 71, the first-layer motor 73, the second-layer motor 75, the screening motor 77, the transfer motor 79, and the third-layer motor 80 can be the feeding motor, the first-layer conveyor motor, the second-layer conveyor motor, the screening motor, the transfer motor, and the third-layer conveyor motor of the tracked heavy-duty screening station, respectively.

[0073] Please refer to Figure 8 When the intermediate motor 79 (i.e., the intermediate motor) or the three-layer motor 80 (i.e., the three-layer conveyor motor) fails, the fifth safety shut-off valve 85 operates, the intermediate motor 79 or the three-layer motor 80 stops and depressurizes, some high-pressure oil reaches the second hydraulic control directional valve 89 through the first shuttle valve 97, causing the second hydraulic control directional valve 89 to switch, and the screening motor 77 (i.e., the screening motor) stops. Some high-pressure oil reaches the first hydraulic control directional valve 87 through the first shuttle valve 97 and the second shuttle valve 98, causing the first hydraulic control directional valve 87 to switch, and the feeding motor 71 (i.e., the feeding motor) stops. The first-layer motor 73 (i.e., the first-layer conveyor motor) and the second-layer motor 75 (i.e., the second-layer conveyor motor) continue to work without being affected.

[0074] Please refer to Figure 9 When the first-layer motor 73 fails, the second safety shut-off valve 82 operates, the first-layer motor 73 stops and depressurizes, and some high-pressure oil reaches the second hydraulic control directional valve 89 through the third shuttle valve 99 and the first shuttle valve 97, causing the second hydraulic control directional valve 89 to switch, and the screening motor 77 (i.e., the screening motor) stops. Some high-pressure oil reaches the first hydraulic control directional valve 87 through the third shuttle valve 99 and the second shuttle valve 98, causing the first hydraulic control directional valve 87 to switch, and the feeding motor 71 (i.e., the feeding motor) stops. The second-layer motor 75, the intermediate motor 79 and the third-layer motor 80 continue to work without being affected.

[0075] Please refer to Figure 10 When the second-layer motor 75 malfunctions, the third safety shut-off valve 83 operates, the second-layer motor 75 stops and depressurizes, and some high-pressure oil passes through the third shuttle valve 99 and the first shuttle valve 97 to the second hydraulic control directional valve 89, causing the second hydraulic control directional valve 89 to switch, and the screening motor 77 (i.e., the screening motor) stops. Some high-pressure oil passes through the third shuttle valve 99 and the second shuttle valve 98 to the first hydraulic control directional valve 87, causing the first hydraulic control directional valve 87 to switch, and the feeding motor 71 (i.e., the feeding motor) stops. The first-layer motor 73, the intermediate motor 79 and the third-layer motor 80 continue to work without being affected.

[0076] Please refer to Figure 11 When the screening motor 77 malfunctions, the fourth safety shut-off valve 84 operates, the screening motor 77 stops and depressurizes, and the high-pressure oil reaches the first hydraulic control directional valve 87 through the second shuttle valve 98, causing the first hydraulic control directional valve 87 to switch, the feeding motor 71 (i.e., the feeding motor) stops, and the first-layer motor 73, the second-layer motor 75, the intermediate motor 79 and the third-layer motor 80 continue to work without being affected.

[0077] Please refer to Figure 12 When the feed motor 71 fails, the first safety shut-off valve 81 operates, the feed motor 71 stops and depressurizes, and the first-layer motor 73, the second-layer motor 75, the screening motor 77, the intermediate motor 79 and the third-layer motor 80 continue to work without being affected.

[0078] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A design method for a hydraulic system of engineering machinery, characterized in that, include: The number of actuators is determined based on the function of the construction machinery; The actuators are classified according to the different functions they perform; The main mode and main actuator are determined based on the functional characteristics of the actuator. The power mechanism is determined based on the working characteristics of the main actuator; A preliminary hydraulic system including the aforementioned main actuator was determined; Based on the working characteristics of the main actuators, the initial hydraulic system is integrated and simplified to form a simplified hydraulic system; A secondary actuator is added to the simplified hydraulic system; and Add auxiliary components to the simplified hydraulic system; wherein, in the step of adding auxiliary components to the simplified hydraulic system, safety shut-off valves are respectively installed on the oil lines of the main actuator; the safety shut-off valves include a variable damper (11), a first valve (13), a second valve (15), a pressure port, a working port, and a return port (21), the variable damper (11) includes an inlet port and an outlet port, the inlet port is connected to the pressure port, and the second valve (15) is connected between the outlet port and the working port of the variable damper (11). The second valve (15) is used to connect the oil outlet of the variable damper (11) to the working oil port or to connect the working oil port to the return oil port (21). The first valve (13) is used to connect the control end of the second valve (15) to the pressure oil port or to connect the control end of the second valve (15) to the return oil port (21). The two control ends of the first valve (13) are respectively connected to the oil inlet and the oil outlet of the variable damper (11) to switch the state according to the pressure of the oil inlet and the oil outlet of the variable damper (11). The first valve (13) includes a spring cavity, which is located at the control end of the first valve (13) connected to the oil outlet of the variable damper (11); the setting parameters of the spring in the spring cavity of the first valve (13) are... Should meet ,in S1 is the setting parameter of the spring in the spring chamber of the first valve (13), and S1 is the area of ​​the fluid acting on the valve core of the first valve (13). The set pressure difference for the variable damping (11); The second valve (15) includes a spring cavity, which is located at the end opposite to the control end of the second valve (15); the setting parameter of the spring in the spring cavity of the second valve (15) should be... satisfy , among which, The spring setting parameters of the spring chamber of the second valve (15) are: S2 is the area of ​​the valve core of the second valve (15) where the fluid acts, and P is the safety setting pressure of the pressure port (17).

2. The design method for a hydraulic system of engineering machinery as described in claim 1, characterized in that, In the step of forming a simplified hydraulic system, actuators with the same load and the same speed are connected in series, and actuators with inverse loads are connected in parallel; whether to install a flow divider valve (66) in the oil circuit of the corresponding actuator is determined according to whether the actuator needs speed regulation; and whether to install a check valve (67) in the oil circuit of the corresponding actuator is determined according to whether the actuator needs to avoid reverse rotation.

3. The design method for hydraulic systems of engineering machinery as described in claim 1, characterized in that, The second valve (15) includes a fourth oil port (151), a fifth oil port (152), and a sixth oil port (153). The fourth oil port (151) is connected to the oil outlet of the variable damper (11), the fifth oil port (152) is connected to the oil return port (21), and the sixth oil port (153) is connected to the working oil port (19). The second valve (15) includes a third position and a fourth position. In the third position, the fourth oil port (151) and the sixth oil port (153) are connected. In the fourth position, the fifth oil port (152) and the sixth oil port (153) are connected.

4. The design method for a hydraulic system of engineering machinery as described in claim 1, characterized in that, The actuator includes a feeding motor (71), a first-layer motor (73), a second-layer motor (75), a screening motor (77), a transfer motor (79), a third-layer motor (80), a left-travel motor (61), a right-travel motor (62), and multiple hydraulic cylinders (63); in the step of classifying the actuators according to their different functions, the feeding motor (71), the first-layer motor (73), the second-layer motor (75), the screening motor (77), the transfer motor (79), and the third-layer motor (80) are classified as follows: The left travel motor (61) and the right travel motor (62) are classified as travel actuators, and the hydraulic cylinder (63) is classified as an auxiliary action actuator. In the step of determining the main mode and the main actuator based on the functional characteristics of the actuator, the main mode is determined to be the working mode, and the feeding motor (71), the first-layer motor (73), the second-layer motor (75), the screening motor (77), the transfer motor (79), and the third-layer motor (80) are the main actuators.

5. The design method for a hydraulic system of engineering machinery as described in claim 4, characterized in that, In the step of determining the initial hydraulic system including the main actuator, multiple oil supply pumps (65) are set to supply oil to the feed motor (71), the first-layer motor (73), the second-layer motor (75), the screening motor (77), the intermediate motor (79), and the third-layer motor (80), respectively. Each of the oil supply pumps (65) is connected to an oil tank, and a connection is set between the oil tank and the feed motor (71), the first-layer motor (73), the second-layer motor (75), the screening motor (77), the intermediate motor (79), and the third-layer motor (80), thus forming the initial hydraulic system.

6. The design method for a hydraulic system of engineering machinery as described in claim 4, characterized in that, In the step of forming the simplified hydraulic system, the intermediate motor (79) and the three-layer motor (80) are connected in series, and the first-layer motor (73) and the second-layer motor (75) are connected in parallel. A flow divider valve (66) is installed on the oil lines corresponding to the feed motor (71), the first-layer motor (73), the second-layer motor (75) and the screening motor (77). A check valve (67) is installed on the oil lines corresponding to the first-layer motor (73), the second-layer motor (75) and the third-layer motor (80). A first main valve (101) is installed on the oil line of the feed motor (71). A second main valve (102) is installed on the oil lines of the first-layer motor (73) and the second-layer motor (75). A third main valve (103) is installed on the oil line of the screening motor (77). A fourth main valve (104) is installed on the oil lines of the intermediate motor (79) and the three-layer motor (80).

7. The design method for a hydraulic system of engineering machinery as described in claim 4, characterized in that, In the step of adding secondary actuators to the simplified hydraulic system, the left travel motor (61), the right travel motor (62), and the cylinder (63) are added to the simplified hydraulic system; when adding auxiliary components to the simplified hydraulic system, a hydraulic lock (68) is installed on the oil line where the cylinder (63) is installed; a radiator and a filter are installed on the return oil line; a travel control valve (69) is installed on the oil lines of the left travel motor (61) and the right travel motor (62); and a remote shut-off valve (70) is installed on the oil lines of the feed motor (71), the first-layer motor (73), and the second-layer motor (75).

8. A hydraulic system for engineering machinery designed using a method for designing hydraulic systems for engineering machinery, characterized in that, It includes a feed motor (71), a first-layer motor (73), a second-layer motor (75), a screening motor (77), a transfer motor (79), a third-layer motor (80), a first main oil circuit (91), a second main oil circuit (92), a third main oil circuit (93), a fourth main oil circuit (94), a left travel motor (61), a right travel motor (62), and an oil cylinder (63). The first main oil circuit (91) is sequentially equipped with a first main valve (101), a remote shut-off valve, a diverter valve, and the feed motor (71). The first main oil circuit (91) is also equipped with the left travel motor (61) and the right travel motor (62) connected to the first main valve (101); the second main oil circuit ( The first main oil circuit (92) is provided with a second main valve (102), a remote shut-off valve, a diversion valve, a check valve, and the first-layer motor (73) and the second-layer motor (75) connected in parallel. The left travel motor (61) and the right travel motor (62) are also connected to the second main valve (102). The third main oil circuit (93) is provided with a third main valve (103), a diversion valve, and the screening motor (77) connected in sequence. The fourth main oil circuit (94) is provided with a fourth main valve (104), a check valve, the transfer motor (79), a diversion valve, a check valve, and the third-layer motor (80) connected in sequence. The first main oil circuit (91) is also provided with an oil cylinder (63) connected in parallel with the feeding motor (71). A first safety shut-off valve (81) is provided between the first main valve (101) and the feed motor (71); a second safety shut-off valve (82) is provided between the second main valve (102) and the first-layer motor (73); a third safety shut-off valve (83) is provided between the second main valve (102) and the second-layer motor (75); a fourth safety shut-off valve (84) is provided between the third main valve (103) and the screening motor (77); and a fifth safety shut-off valve (85) is provided between the fourth main valve (104) and the transfer motor (79). The first safety shut-off valve (81), the second safety shut-off valve (82), the third safety shut-off valve (83), the fourth safety shut-off valve (84), and the fifth safety shut-off valve (85) all include a variable damping (11), a first valve (13), and a second valve (14). 15) Pressure port, working port and return port (21), the variable damper (11) includes an inlet port and an outlet port, the inlet port is connected to the pressure port, the second valve (15) is connected between the outlet port and the working port of the variable damper (11), the second valve (15) is used to connect the outlet port of the variable damper (11) with the working port or connect the working port with the return port (21), the first valve (13) is used to connect the control end of the second valve (15) with the pressure port or connect the control end of the second valve (15) with the return port (21), the two control ends of the first valve (13) are respectively connected to the inlet port and the outlet port of the variable damper (11) to switch the state according to the pressure of the inlet port and the outlet port of the variable damper (11); The first valve (13) includes a spring cavity, which is located at the control end of the first valve (13) connected to the oil outlet of the variable damper (11); the setting parameters of the spring in the spring cavity of the first valve (13) are... Should meet ,in S1 is the setting parameter of the spring in the spring chamber of the first valve (13), and S1 is the area of ​​the fluid acting on the valve core of the first valve (13). The set pressure difference for the variable damping (11); The second valve (15) includes a spring cavity, which is located at the end opposite to the control end of the second valve (15); the setting parameter of the spring in the spring cavity of the second valve (15) should be... satisfy , among which, The spring setting parameters of the spring chamber of the second valve (15) are: S2 is the area of ​​the valve core of the second valve (15) where the fluid acts, and P is the safety setting pressure of the pressure port (17).

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