Hydraulic control system for construction machinery, hydraulic control operation methods and construction machinery

Abstract

A hydraulic control system for engineering machinery includes a control valve assembly, a control handle, an actuator, a pilot control oil circuit, and a controller. The control valve assembly connects the control handle and the actuator. The pilot control oil circuit includes a pilot oil source, a switching valve, and a pilot oil control valve. The inlet of the switching valve is connected to the pilot oil source, and its two working ports are connected to the control handle via a first oil circuit and a second oil circuit, respectively. The pilot oil control valve is located on the second oil circuit. The switching valve and the pilot oil control valve are connected to the controller. The controller controls the opening of either the first or second oil circuit by controlling the switching valve. When the second oil circuit is open, the controller also receives action signals and adjusts the pressure of the hydraulic oil passing through the pilot oil control valve according to the received action signals. This hydraulic control system can solve the problem of large differences in the deceleration ratio during different actions, and it has a simple structure, low cost, and is easy to implement. This invention also relates to a hydraulic control operation method for engineering machinery and the engineering machinery itself.

Description

Technical Field

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

[0002] Construction machinery is an important component of the equipment manufacturing industry. Construction machinery refers to all the mechanical equipment necessary for comprehensive mechanized construction projects, including earthwork construction, road construction and maintenance, mobile lifting and loading operations, and various building projects.

[0003] Mobile cranes are commonly used construction machinery in mobile lifting and loading / unloading operations. Mobile cranes mainly include truck cranes, tire cranes, crawler cranes, and specialized mobile cranes. Their working mechanisms primarily consist of: a luffing mechanism for changing the boom angle, a telescopic mechanism for changing the boom length, a winching mechanism for lifting and lowering loads, and a slewing mechanism for the horizontal circular motion of the upper structure. The working mechanisms are typically controlled by levers and pedals to control the luffing, telescopic, winching, and slewing actions. Based on the type of lever, they can be categorized as electrically controlled or hydraulically controlled.

[0004] In the hydraulic control system of a mobile crane, the hoisting action is driven by a hoisting motor, the luffing action by a luffing cylinder, and the slewing action by a slewing motor. The pumps supplying hydraulic oil to the hoisting motor and luffing cylinder are typically variable displacement pumps, while those supplying hydraulic oil to the slewing motor are typically fixed displacement pumps. Existing technology usually incorporates a pressure reducing valve in the pilot oil circuit to reduce the speed of each action, ensuring the pilot control pressure is reduced before being supplied to the operating handle. However, due to differences in drive methods and hydraulic system principles, the pilot control pressure-flow output characteristics differ for each action; that is, under the same pilot control pressure, the hydraulic oil flow rate obtained by each working mechanism is not the same.

[0005] In practical applications, the actions with significant differences in pilot control pressure-flow output characteristics are hoisting, luffing, and slewing. In existing deceleration schemes, the pressure-reducing valve is set to a fixed value. When the hoisting speed is the deceleration target, the luffing and slewing speeds will be very slow, or even nonexistent. When the luffing or slewing speed is the deceleration target, the hoisting speed reduction is not significant and fails to meet the deceleration requirements. In summary, in existing hydraulic control systems, there is a problem of large differences in the deceleration ratio for each action. Summary of the Invention

[0006] In view of this, the present invention provides a hydraulic control system for engineering machinery and engineering machinery having the hydraulic control system, which can solve the problem of large differences in the deceleration ratio during different actions, and has a simple structure, low cost and is easy to implement.

[0007] This invention provides a hydraulic control operating system for engineering machinery, comprising a control valve assembly, a control handle, and an actuator. The control valve assembly is connected to the control handle and the actuator, respectively. It also includes a pilot control oil circuit and a controller. The pilot control oil circuit includes a pilot oil source, a switching valve, and a pilot oil control valve. The inlet of the switching valve is connected to the pilot oil source, and the two working ports of the switching valve are connected to the control handle via a first oil circuit and a second oil circuit, respectively. The pilot oil control valve is disposed on the second oil circuit. Both the switching valve and the pilot oil control valve are connected to the controller. The controller controls the opening of either the first or second oil circuit by controlling the switching valve. When the second oil circuit is open, the controller is also used to receive an action signal and adjust the pressure of the hydraulic oil passing through the pilot oil control valve according to the received action signal.

[0008] Furthermore, the control valve assembly includes a rotary valve and a multi-way valve, the actuators include a rotary motor and a luffing cylinder, the control handle is connected to the two inlets of the rotary valve via a left rotary pilot oil circuit and a right rotary pilot oil circuit, the two outlets of the rotary valve are connected to the rotary motor, the control handle is connected to the two inlets of the multi-way valve via a luffing drop pilot oil circuit and a luffing rise pilot oil circuit, and the two outlets of the multi-way valve are connected to the luffing cylinder; the action signals include a rotary action signal and a luffing drop action signal, when the controller receives the rotary action signal, it controls the hydraulic oil passing through the pilot oil control valve to have a first pressure, when the controller receives the luffing drop action signal, it controls the hydraulic oil passing through the pilot oil control valve to have a second pressure, wherein the first pressure is less than the second pressure.

[0009] Furthermore, when the controller simultaneously receives the slewing action signal and the luffing action signal, the controller controls the hydraulic oil through the pilot oil control valve to have a third pressure, wherein the third pressure is greater than or equal to the second pressure.

[0010] Furthermore, the hydraulic control system of the construction machinery also includes a first sensor, a second sensor, and a third sensor; the first sensor is connected to the left slewing pilot oil circuit, the second sensor is connected to the right slewing pilot oil circuit, and the third sensor is connected to the luffing drop pilot oil circuit; the first sensor, the second sensor, and the third sensor are also connected to the controller; the first sensor is used to detect the hydraulic oil pressure of the left slewing pilot oil circuit, the second sensor is used to detect the hydraulic oil pressure of the right slewing pilot oil circuit to generate the slewing action signal to be sent to the controller, and the third sensor is used to detect the hydraulic oil pressure of the luffing drop pilot oil circuit to generate the luffing drop action signal to be sent to the controller.

[0011] Furthermore, the hydraulic control system of the engineering machinery also includes a shuttle valve, a fourth sensor, and a fifth sensor; the two oil inlets of the shuttle valve are respectively connected to the left slewing pilot oil circuit and the right slewing pilot oil circuit, the oil outlet of the shuttle valve is connected to the fourth sensor, and the fifth sensor is connected to the luffing drop pilot oil circuit; the fourth sensor is used to detect the hydraulic oil pressure of the left slewing pilot oil circuit or the right slewing pilot oil circuit to generate the slewing action signal to be sent to the controller, and the fifth sensor is used to detect the hydraulic oil pressure of the luffing drop pilot oil circuit to generate the luffing drop action signal to be sent to the controller.

[0012] Furthermore, the control handle is connected to the controller, and the control handle generates the slewing action signal and / or the amplitude drop action signal and sends them to the controller.

[0013] Furthermore, the actuator also includes a winch motor, and the control handle is connected to two inlets of the multi-way valve via a winch lowering pilot oil circuit and a winch lifting pilot oil circuit, and the two outlets of the multi-way valve are connected to the winch motor; when the controller does not receive the slewing action signal and / or the luffing lowering action signal, the controller controls the hydraulic oil through the pilot oil control valve to have a fourth pressure, which is less than the first pressure.

[0014] Furthermore, the pilot oil control valve has an electrically driven terminal Y. S1 The controller controls the electric drive terminal Y. S1 Different current values ​​are input to control the pressure of the hydraulic oil passing through the pilot oil control valve. The larger the current value input to the controller, the greater the pressure of the hydraulic oil passing through the pilot oil control valve.

[0015] Furthermore, a one-way valve is also provided in the second oil circuit, the one-way valve being connected between the pilot oil control valve and the control handle.

[0016] The present invention also provides a hydraulic control operation method for engineering machinery, used to operate the above-mentioned hydraulic control system. When the hydraulic control system of the engineering machinery does not need to decelerate, the controller controls the first oil circuit to be opened. When the hydraulic control system of the engineering machinery needs to decelerate, the controller controls the second oil circuit to be opened.

[0017] The action signals include a luffing action signal and a slewing action signal, and when controlling the second oil circuit to open, they also include:

[0018] When the controller receives the slewing action signal, the controller controls the hydraulic oil through the pilot oil control valve to have a first pressure; when the controller receives the luffing action signal, the controller controls the hydraulic oil through the pilot oil control valve to have a second pressure; when the controller receives both the slewing action signal and the luffing action signal, the controller controls the hydraulic oil through the pilot oil control valve to have a third pressure; when the controller does not receive the slewing action signal and / or the luffing action signal, the controller controls the hydraulic oil through the pilot oil control valve to have a fourth pressure; wherein, the first pressure is less than the second pressure, the third pressure is greater than or equal to the second pressure, and the fourth pressure is less than the first pressure.

[0019] Furthermore, the switching valve has an electrically controlled terminal Y1, and the pilot oil control valve has an electrically driven terminal Y. S1 ;

[0020] When the electrical control terminal Y1 of the controller and the electrical drive terminal Y of the pilot oil control valve S1 When there is no power, the first oil circuit is activated;

[0021] When the controller energizes the electrical control terminal Y1 of the switching valve, it simultaneously inputs a current value I1 to the electrical drive terminal Y of the pilot oil control valve. S1 At this time, the hydraulic oil has the fourth pressure through the pilot oil control valve;

[0022] When the controller energizes the electrical control terminal Y1 of the switching valve, it simultaneously inputs a current value I2 to the electrical drive terminal Y of the pilot oil control valve. S1 At this time, the hydraulic oil through the pilot oil control valve has the first pressure;

[0023] When the controller energizes the electrical control terminal Y1 of the switching valve, it simultaneously inputs a current value I3 to the electrical drive terminal Y of the pilot oil control valve. S1 At this time, the hydraulic oil through the pilot oil control valve has the second pressure;

[0024] When the controller energizes the electrical control terminal Y1 of the switching valve, it simultaneously inputs a current value I4 to the electrical drive terminal Y of the pilot oil control valve. S1 At this time, the hydraulic oil has the third pressure through the pilot oil control valve;

[0025] Among them, the current values ​​I4≥I3>I2>I1.

[0026] The present invention also provides an engineering machine, including the above-mentioned hydraulic control system.

[0027] In summary, the hydraulic control system for engineering machinery of the present invention includes a control valve assembly, a control handle, and an actuator, with the control valve assembly connected to both the control handle and the actuator. It also includes a pilot control oil circuit and a controller. The pilot control oil circuit includes a pilot oil source, a switching valve, and a pilot oil control valve. The inlet of the switching valve is connected to the pilot oil source, and the two working ports of the switching valve are connected to the control handle via a first oil circuit and a second oil circuit, respectively. The pilot oil control valve is located on the second oil circuit. Both the switching valve and the pilot oil control valve are connected to the controller. The controller controls the opening of either the first or second oil circuit by controlling the switching valve. When the second oil circuit is open, the controller also receives action signals and adjusts the pressure of the hydraulic oil passing through the pilot oil control valve according to the received action signals. The hydraulic control system for engineering machinery of the present invention can solve the problem of large differences in the deceleration ratio during different actions, and it has a simple structure, low cost, and is easy to implement.

[0028] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described in detail below with reference to the accompanying drawings. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the hydraulic control system of the engineering machinery according to the first embodiment of the present invention.

[0030] Figure 2 This is a connection diagram of some electronic control components in the hydraulic control operating system of the engineering machinery according to the first embodiment of the present invention.

[0031] Figure 3 It is a pilot control pressure-flow curve diagram in the hydraulic control system of engineering machinery.

[0032] Figure 4 This is a schematic diagram of the hydraulic control system for engineering machinery according to the second embodiment of the present invention.

[0033] Figure 5 This is a connection diagram of some electronic control components in the hydraulic control operating system of engineering machinery according to the second embodiment of the present invention.

[0034] Figure 6 This is a schematic diagram of the hydraulic control system of the engineering machinery according to the third embodiment of the present invention.

[0035] Figure 7 This is a connection diagram of some electronic control components in the hydraulic control operating system of engineering machinery according to the third embodiment of the present invention. Detailed Implementation

[0036] To further illustrate the technical means and effects adopted by the present invention in order to achieve the intended purpose, the present invention will be described in detail below with reference to the accompanying drawings and preferred embodiments.

[0037] Figure 1 This is a schematic diagram of the hydraulic control system of the engineering machinery according to the first embodiment of the present invention. Figure 2 This is a connection diagram of some electronic control components in the hydraulic control operating system of the engineering machinery according to the first embodiment of the present invention. Please refer to it as well. Figure 1 and Figure 2 The hydraulic control system of the engineering machinery in this embodiment includes a control valve group 10, a control handle 20, an actuator 30, a pilot control oil circuit 40, and a controller 50. The control valve group 10 is connected to the control handle 20 and the actuator 30 respectively.

[0038] The pilot control oil circuit 40 includes a pilot oil source 41, a switching valve 42, and a pilot oil control valve 43. The oil inlet of the switching valve 42 is connected to the pilot oil source 41. The two working oil ports of the switching valve 42 are connected to the control handle 20 through the first oil circuit 101 and the second oil circuit 102, respectively. The pilot oil control valve 43 is set on the second oil circuit 102. Both the switching valve 42 and the pilot oil control valve 43 are connected to the controller 50. The controller 50 controls the conduction of the first oil circuit 101 or the second oil circuit 102 by controlling the switching valve 42. When the second oil circuit 102 is conducted, the controller 50 is also used to receive action signals and adjust the pressure of the hydraulic oil passing through the pilot oil control valve 43 according to the received action signals.

[0039] In this embodiment, the control handle 20 includes a first handle 21 and a second handle 22. The first handle 21 is, for example, a left handle, and the second handle 22 is, for example, a right handle. The user can perform corresponding actions by operating the first handle 21 and the second handle 22.

[0040] Furthermore, the control valve assembly 10 includes a rotary valve 11, the actuator 30 includes a rotary motor 31, and the control handle 20 is connected to the two inlets of the rotary valve 11 via a left rotary pilot oil passage 103 and a right rotary pilot oil passage 104. The two outlets of the rotary valve 11 are connected to the rotary motor 31. The rotary motor 31 can perform either a left rotary or a right rotary action when it is running. When the left rotary pilot oil passage 103 is open, the rotary motor 31 performs a left rotary action; when the right rotary pilot oil passage 104 is open, the rotary motor 31 performs a right rotary action.

[0041] The control valve assembly 10 also includes a multi-way valve 12, and the actuator 30 includes a luffing cylinder 32. The control handle 20 is connected to the two inlets of the multi-way valve 12 via a luffing lowering pilot oil circuit 105 and a luffing raising pilot oil circuit 106. The two outlets of the multi-way valve 12 are connected to the luffing cylinder 32. When the luffing cylinder 32 is in operation, it can perform luffing lowering and luffing raising actions. When the luffing lowering pilot oil circuit 105 is open, the luffing cylinder 32 performs the luffing lowering action. When the luffing raising pilot oil circuit 106 is open, the luffing cylinder 32 performs the luffing raising action.

[0042] Because the pilot control pressure-flow output characteristics differ significantly for actions such as hoisting, luffing, and slewing, etc. Figure 3 As shown in the figure, curve A is the pilot control pressure-flow rate curve for the luffing and lowering action, curve B is the pilot control pressure-flow rate curve for the slewing action, and curve C is the pilot control pressure-flow rate curve for the hoisting action (including hoisting and lowering). The figures show that, with the same pilot control pressure, the flow rate output increases sequentially for the luffing and lowering action, the slewing action, and the hoisting action, and the smaller the pilot control pressure, the greater the flow rate difference. In other words, to ensure smooth operation of each action, different pilot control pressures are required for different actions, especially for the luffing and lowering and slewing actions. Furthermore, the action signals received by the controller 50 include slewing action signals and luffing action signals. When the controller 50 receives the slewing action signal, it controls the hydraulic oil through the pilot oil control valve 43 to have a first pressure. When the controller 50 receives the luffing action signal, it controls the hydraulic oil through the pilot oil control valve 43 to have a second pressure. The first pressure is less than the second pressure, that is, the pilot control pressure when performing the luffing action is greater than the pilot control pressure when performing the slewing action.

[0043] Furthermore, when the controller 50 receives both the slewing action signal and the luffing action signal simultaneously, the controller 50 controls the hydraulic oil through the pilot oil control valve 43 to have a third pressure, wherein the third pressure is greater than or equal to the second pressure. That is to say, when the luffing action and the slewing action are executed simultaneously, the pilot control pressure is greater than or equal to the pilot control pressure when the luffing action is executed alone.

[0044] In this embodiment, the hydraulic control system of the construction machinery includes a first sensor 1031, a second sensor 1041, and a third sensor 1051. The first sensor 1031 is connected to the left slewing pilot oil circuit 103, the second sensor 1041 is connected to the right slewing pilot oil circuit 104, and the third sensor 1051 is connected to the luffing drop pilot oil circuit 105. The first sensor 1011, the second sensor 1021, and the third sensor 1031 are also all connected to the controller 50.

[0045] In this embodiment, the first sensor 1031, the second sensor 1041, and the third sensor 1051 are all pressure sensors.

[0046] The first sensor 1031 is used to detect the hydraulic oil pressure of the left slewing pilot oil circuit 103 to generate a slewing action signal and send it to the controller 50. The second sensor 1041 is used to detect the hydraulic oil pressure of the right slewing pilot oil circuit 104 to generate a slewing action signal and send it to the controller 50. That is to say, a slewing action signal will be generated when either the left or right slewing action is performed.

[0047] The third sensor 1051 is used to detect the hydraulic oil pressure of the luffing pilot oil circuit 105 to generate a luffing action signal to be sent to the controller 50.

[0048] When the controller 50 receives a slewing action signal or a luffing action signal, it controls the second oil circuit 102 to open, and simultaneously adjusts the pressure of the hydraulic oil passing through the pilot oil control valve 43 according to the different action signals. In this way, when performing the luffing action, the pressure of the hydraulic oil passing through the pilot oil control valve 43 will be greater than when performing the slewing action, thus solving the problem of large differences in the deceleration ratio between different actions during deceleration.

[0049] Furthermore, the actuator 30 also includes a winch motor 33. The control handle 20 is connected to two inlets of the multi-way valve 12 via the winch lowering pilot oil circuit 107 and the winch lifting pilot oil circuit 108. The two outlets of the multi-way valve 12 are connected to the winch motor 33. When the controller 50 does not receive a slewing action signal and / or a luffing lowering action signal, the controller 50 controls the hydraulic oil through the pilot oil control valve 43 to have a fourth pressure, which is less than the first pressure. When the controller 50 does not receive a slewing action signal and / or a luffing lowering action signal, it means that the action being performed is something other than the slewing action and / or the luffing lowering action, such as a winch lifting action or a winch lowering action. In this case, the pilot control pressure required to perform these actions is lower than that required to perform the slewing action.

[0050] In this embodiment, the pilot oil control valve 43 is, for example, an electro-proportional directional valve, but is not limited thereto. The pilot oil control valve 43 has an electrically driven terminal Y. S1 ; Controller 50 controls the electric drive terminal Y S1 Different current values ​​are input to control the pressure of the hydraulic oil passing through the pilot oil control valve 43. The larger the current value input to the controller 50, the greater the pressure of the hydraulic oil passing through the pilot oil control valve 43.

[0051] Furthermore, a check valve 44 is also provided on the second oil circuit 102, which is connected between the pilot oil control valve 43 and the control handle 20. When the first oil circuit 101 is open, the check valve 44 can prevent pilot oil from flowing back from the second oil circuit 102 into the pilot oil control valve 43.

[0052] Furthermore, a balance valve 34 is provided between the luffing cylinder 32 and the multi-way valve 12. The pilot control end of the balance valve 34 is connected to the luffing lowering pilot oil circuit 105 through the luffing balance valve opening oil circuit 109. A balance valve 35 is also provided between the hoisting motor 33 and the multi-way valve 12.

[0053] Furthermore, the hydraulic control system also includes a first pump 61 and a second pump 62. The first pump 61 is connected to a multi-way valve 12 to pump hydraulic oil to the multi-way valve 12, and the second pump 62 is connected to a rotary valve 11 to pump hydraulic oil to the rotary valve 11. The first pump 61 is a variable displacement pump, and the second pump 62 is a fixed displacement pump.

[0054] The following is the specific control principle of the hydraulic control system in this embodiment:

[0055] 1. Deceleration condition not triggered: When controller 50 controls the electrical control terminal Y1 of switching valve 42 and the electrical drive terminal Y of pilot oil control valve 43 S1 When there is no power, the first oil circuit 101 in the pilot control oil circuit 40 is turned on, the pilot control pressure is not limited, and the pilot control oil circuit 40 does not decelerate.

[0056] 2. Deceleration condition triggered:

[0057] a: When the first sensor 1031, the second sensor 1041, and the third sensor 1051 have no pressure signal, it means that the slewing action and / or the luffing action will not be operated. At this time, the controller 50 controls the electrical control terminal Y1 of the switching valve 42 to be energized, and at the same time, the current value I1 is input to the electrical drive terminal Y of the pilot oil control valve 43. S1 The hydraulic oil has a fourth pressure through the pilot oil control valve 43;

[0058] b: When the first sensor 1031 or the second sensor 1041 has a pressure signal, and the third sensor 1051 has no pressure signal, it indicates that the slewing action is being performed, and the luffing action is not being performed. At this time, the controller 50 controls the electrical control terminal Y1 of the switching valve 42 to be energized, and at the same time inputs the current value I2 to the electrical drive terminal Y of the pilot oil control valve 43. S1 The hydraulic oil has a first pressure through the pilot oil control valve 43;

[0059] c: When the first sensor 1031 or the second sensor 1041 has no pressure signal, and the third sensor 1051 has a pressure signal, it indicates that the luffing action is operated, but the slewing action is not operated. At this time, the controller 50 controls the electrical control terminal Y1 of the switching valve 42 to be energized, and at the same time inputs the current value I3 to the electrical drive terminal Y of the pilot oil control valve 43. S1 The hydraulic oil has a second pressure through the pilot oil control valve 43;

[0060] d: When the first sensor 1031 and the third sensor 1051 simultaneously receive pressure signals, or when the second sensor 1031 and the third sensor 1051 simultaneously receive pressure signals, it indicates that the slewing action and the luffing action are being operated simultaneously. At this time, the controller 50 controls the electrical control terminal Y1 of the switching valve 42 to be energized, and simultaneously inputs the current value I4 to the electrical drive terminal Y of the pilot oil control valve 43. S1 The hydraulic oil has a third pressure through the pilot oil control valve 43;

[0061] Among them, the current value I4≥I3>I2>I1, and the specific current value can be theoretically calculated based on the pilot pressure-flow curve and the characteristics of the pilot oil control valve 43, or it can be calibrated through experiments.

[0062] [Second Embodiment]

[0063] Figure 4 This is a schematic diagram of the hydraulic control system of the engineering machinery according to the second embodiment of the present invention. Figure 5 This is a connection diagram of some electronic control components in the hydraulic control operating system of the engineering machinery according to the second embodiment of the present invention. Please refer to it as well. Figure 4 and Figure 5 The hydraulic control system of the second embodiment differs from that of the first embodiment in that the hydraulic control system of this embodiment includes a shuttle valve 1032, a fourth sensor 1033, and a fifth sensor 1052. The two inlets of the shuttle valve 1032 are connected to the left slewing pilot oil circuit 103 and the right slewing pilot oil circuit 104, respectively; the outlet of the shuttle valve 1032 is connected to the fourth sensor 1033; and the fifth sensor 1052 is connected to the luffing drop pilot oil circuit 105.

[0064] Both the fourth sensor 1033 and the fifth sensor 1052 are pressure sensors. The fourth sensor 1033 is used to detect the hydraulic oil pressure in the left slewing pilot oil circuit 103 or the right slewing pilot oil circuit 104 to generate a slewing action signal to be sent to the controller 50. The fifth sensor 1052 is used to detect the hydraulic oil pressure in the luffing drop pilot oil circuit 105 to generate a luffing drop action signal to be sent to the controller 50.

[0065] The following is the specific control principle of the hydraulic control system in this embodiment:

[0066] 1. Deceleration condition not triggered: When controller 50 controls the electrical control terminal Y1 of switching valve 42 and the electrical drive terminal Y of pilot oil control valve 43 S1 When there is no power, the first oil circuit 101 in the pilot control oil circuit 40 is turned on, the pilot control pressure is not limited, and the pilot control oil circuit 40 does not decelerate.

[0067] 2. Deceleration condition triggered:

[0068] a: When the fourth sensor 1033 and the fifth sensor 1052 have no pressure signal, it means that the slewing action and / or the luffing action will not be operated. At this time, the controller 50 controls the electrical control terminal Y1 of the switching valve 42 to be energized, and at the same time, the current value I1 is input to the electrical drive terminal Y of the pilot oil control valve 43. S1 The hydraulic oil has a fourth pressure through the pilot oil control valve 43;

[0069] b: When the fourth sensor 1033 has a pressure signal and the fifth sensor 1052 has no pressure signal, it indicates that the slewing action is being performed and the luffing action is not being performed. At this time, the controller 50 controls the electrical control terminal Y1 of the switching valve 42 to be energized, and at the same time, inputs the current value I2 to the electrical drive terminal Y of the pilot oil control valve 43. S1 The hydraulic oil has a first pressure through the pilot oil control valve 43;

[0070] c: When the fourth sensor 1033 has no pressure signal and the fifth sensor 1052 has a pressure signal, it indicates that the luffing action is activated but the slewing action is not activated. At this time, the controller 50 controls the electrical control terminal Y1 of the switching valve 42 to be energized, and simultaneously inputs a current value I3 to the electrical drive terminal Y of the pilot oil control valve 43. S1 The hydraulic oil has a second pressure through the pilot oil control valve 43;

[0071] d: When the fourth sensor 1033 and the fifth sensor 1052 simultaneously receive pressure signals, it indicates that the slewing action and the luffing action are operated simultaneously. At this time, the controller 50 controls the electrical control terminal Y1 of the switching valve 42 to be energized, and simultaneously inputs the current value I4 to the electrical drive terminal Y of the pilot oil control valve 43. S1 The hydraulic oil has a third pressure through the pilot oil control valve 43;

[0072] Among them, the current values ​​I4≥I3>I2>I1.

[0073] [Third Embodiment]

[0074] Figure 6 This is a schematic diagram of the hydraulic control system of the engineering machinery according to the third embodiment of the present invention. Figure 7 This is a connection diagram of some electronic control components in the hydraulic control operating system of the engineering machinery according to the third embodiment of the present invention. Please refer to it as well. Figure 6 and Figure 7The difference between the hydraulic control operating system of the third embodiment and that of the first embodiment is that...

[0075] In this embodiment, the control handle 20 is connected to the controller 50. The control handle 20 generates a slewing motion signal and / or a luffing motion signal, which is then sent to the controller 50. The control handle 20 is a handle with direction and position detection. The control handle 20 directly identifies the current action being performed by the construction machinery and sends the action control signal to the controller 50 to adjust the pressure of the hydraulic oil passing through the pilot oil control valve 43.

[0076] The following is the specific control principle of the hydraulic control system in this embodiment:

[0077] 1. Deceleration condition not triggered: When controller 50 controls the electrical control terminal Y1 of switching valve 42 and the electrical drive terminal Y of pilot oil control valve 43 S1 When there is no power, the first oil circuit 101 in the pilot control oil circuit 40 is turned on, the pilot control pressure is not limited, and the pilot control oil circuit 40 does not decelerate.

[0078] 2. Deceleration condition triggered:

[0079] a: When the control handle 20 does not send a slewing action and / or luffing action signal, the controller 50 controls the electrical control terminal Y1 of the switching valve 42 to be energized, and simultaneously inputs a current value I1 to the electrical drive terminal Y of the pilot oil control valve 43. S1 The hydraulic oil has a fourth pressure through the pilot oil control valve 43;

[0080] b: When the control handle 20 sends a rotation signal, the controller 50 energizes the electrical control terminal Y1 of the switching valve 42, and simultaneously inputs a current value I2 to the electrical drive terminal Y of the pilot oil control valve 43. S1 The hydraulic oil has a first pressure through the pilot oil control valve 43;

[0081] c: When the control handle 20 sends the luffing action signal, the controller 50 controls the electrical control terminal Y1 of the switching valve 42 to be energized, and simultaneously inputs a current value I3 to the electrical drive terminal Y of the pilot oil control valve 43. S1 The hydraulic oil has a second pressure through the pilot oil control valve 43;

[0082] d: When the control handle 20 simultaneously sends slewing and luffing signals, the controller 50 energizes the electrical control terminal Y1 of the switching valve 42, and simultaneously inputs a current value I4 to the electrical drive terminal Y of the pilot oil control valve 43. S1 The hydraulic oil has a third pressure through the pilot oil control valve 43;

[0083] Among them, the current values ​​I4≥I3>I2>I1.

[0084] The present invention also relates to an engineering machine, including the aforementioned hydraulic control system. The engineering machine is preferably a mobile crane; other structures of the engineering machine are well known to those skilled in the art and will not be described in detail here.

[0085] The hydraulic control system of the engineering machinery of the present invention includes a control valve group 10, a control handle 20, an actuator 30, a control oil circuit 40, and a controller 50. The control valve group 10 is connected to the control handle 20 and the actuator 30 respectively. The pilot control oil circuit 40 includes a pilot oil source 41, a switching valve 42, and a pilot oil control valve 43. The oil inlet of the switching valve 42 is connected to the pilot oil source 41. The two working oil ports of the switching valve 42 are respectively connected to the control handle 20 through the first oil circuit 101 and the second oil circuit 102. The pilot oil control valve 43 is set on the second oil circuit 102. Both the switching valve 42 and the pilot oil control valve 43 are connected to the controller 50. The controller 50 controls the conduction of the first oil circuit 101 or the second oil circuit 102 by controlling the switching valve 42. When the second oil circuit 102 is conducted, the controller 50 is also used to receive action signals and adjust the pressure of the hydraulic oil passing through the pilot oil control valve 43 according to the received action signals. The hydraulic control operating system of the engineering machinery of the present invention can solve the problem of large differences in the deceleration ratio during different actions, and has a simple structure, low cost, and is easy to implement.

[0086] The above description is merely a preferred embodiment of the present invention and is 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 hydraulic control system for engineering machinery, comprising a control valve assembly (10), a control handle (20), and an actuator (30), wherein the control valve assembly (10) is respectively connected to the control handle (20) and the actuator (30), characterized in that, It also includes a pilot control oil circuit (40) and a controller (50). The pilot control oil circuit (40) includes a pilot oil source (41), a switching valve (42), and a pilot oil control valve (43). The oil inlet of the switching valve (42) is connected to the pilot oil source (41). The two working oil ports of the switching valve (42) are respectively connected to the control handle (20) through the first oil circuit (101) and the second oil circuit (102). The pilot oil control valve (43) is set on the second oil circuit (102). The switching valve (42) and the pilot oil control valve (43) are both connected to the controller (50). The controller (50) controls the opening of the first oil circuit (101) or the second oil circuit (102) by controlling the switching valve (42). When the second oil circuit (102) is open, the controller (50) is also used to receive action signals and adjust the pressure of the hydraulic oil passing through the pilot oil control valve (43) according to the received action signals. The control valve assembly (10) includes a rotary valve (11) and a multi-way valve (12). The actuator (30) includes a rotary motor (31) and a luffing cylinder (32). The control handle (20) is connected to the two inlets of the rotary valve (11) via a left rotary pilot oil passage (103) and a right rotary pilot oil passage (104). The two outlets of the rotary valve (11) are connected to the rotary motor (31). The control handle (20) is connected to the multi-way valve (32) via a luffing drop pilot oil passage (105) and a luffing start pilot oil passage (106). The two inlets of the multi-way valve (12) are connected, and the two outlets of the multi-way valve (12) are connected to the luffing cylinder (32). The action signal includes a slewing action signal and a luffing drop action signal. When the controller (50) receives the slewing action signal, it controls the hydraulic oil through the pilot oil control valve (43) to have a first pressure. When the controller (50) receives the luffing drop action signal, it controls the hydraulic oil through the pilot oil control valve (43) to have a second pressure. The first pressure is less than the second pressure.

2. The hydraulic control operating system for engineering machinery as described in claim 1, characterized in that, When the controller (50) receives both the slewing action signal and the luffing action signal, the controller (50) controls the hydraulic oil through the pilot oil control valve (43) to have a third pressure, wherein the third pressure is greater than or equal to the second pressure.

3. The hydraulic control operating system for engineering machinery as described in claim 1 or 2, characterized in that, The hydraulic control system of the engineering machinery also includes a first sensor (1031), a second sensor (1041), and a third sensor (1051); the first sensor (1031) is connected to the left slewing pilot oil circuit (103), the second sensor (1041) is connected to the right slewing pilot oil circuit (104), and the third sensor (1051) is connected to the luffing drop pilot oil circuit (105); the first sensor (1011), the second sensor (1021), and the third sensor (1031) are also connected to the controller (50); The first sensor (1031) is used to detect the hydraulic oil pressure of the left slewing pilot oil circuit (103), the second sensor (1041) is used to detect the hydraulic oil pressure of the right slewing pilot oil circuit (104) to generate the slewing action signal and send it to the controller (50), and the third sensor (1051) is used to detect the hydraulic oil pressure of the luffing drop pilot oil circuit (105) to generate the luffing drop action signal and send it to the controller (50).

4. The hydraulic control operating system for engineering machinery as described in claim 1 or 2, characterized in that, The hydraulic control system of the engineering machinery also includes a shuttle valve (1032), a fourth sensor (1033), and a fifth sensor (1052); the two oil inlets of the shuttle valve (1032) are respectively connected to the left slewing pilot oil circuit (103) and the right slewing pilot oil circuit (104), the oil outlet of the shuttle valve (1032) is connected to the fourth sensor (1033), and the fifth sensor (1052) is connected to the luffing drop pilot oil circuit (105); The fourth sensor (1033) is used to detect the hydraulic oil pressure of the left slewing pilot oil circuit (103) or the right slewing pilot oil circuit (104) to generate the slewing action signal and send it to the controller (50). The fifth sensor (1052) is used to detect the hydraulic oil pressure of the luffing drop pilot oil circuit (105) to generate the luffing drop action signal and send it to the controller (50).

5. The hydraulic control operating system for engineering machinery as described in claim 1 or 2, characterized in that, The control handle (20) is connected to the controller (50), and the control handle (20) generates the slewing action signal and / or the amplitude drop action signal and sends them to the controller (50).

6. The hydraulic control operating system for engineering machinery as described in claim 1 or 2, characterized in that, The actuator (30) further includes a winch motor (33), and the control handle (20) is connected to the two inlets of the multi-way valve (12) through the winch lowering pilot oil circuit (107) and the winch lifting pilot oil circuit (108). The two outlets of the multi-way valve (12) are connected to the winch motor (33). When the controller (50) does not receive the slewing action signal and / or the luffing lowering action signal, the controller (50) controls the hydraulic oil through the pilot oil control valve (43) to have a fourth pressure, which is less than the first pressure.

7. The hydraulic control operating system for engineering machinery as described in claim 1 or 2, characterized in that, The pilot oil control valve (43) has an electrically driven terminal Y S1 The controller (50) controls the electric drive terminal Y. S1 Different current values ​​are input to control the pressure of hydraulic oil passing through the pilot oil control valve (43). The greater the current value input to the controller (50), the greater the pressure of hydraulic oil passing through the pilot oil control valve (43).

8. The hydraulic control operating system for engineering machinery as described in claim 1, characterized in that, The second oil circuit (102) is also provided with a check valve (44), which is connected between the pilot oil control valve (43) and the control handle (20).

9. A hydraulic control operation method for engineering machinery, characterized in that, For operating the hydraulic control system as described in any one of claims 1 to 8, when the hydraulic control system of the construction machinery does not need to decelerate, the controller (50) controls the first oil circuit (101) to be turned on, and when the hydraulic control system of the construction machinery needs to decelerate, the controller (50) controls the second oil circuit (101) to be turned on; The action signals include a luffing action signal and a slewing action signal, and when controlling the second oil circuit (101) to be turned on, they also include: When the controller (50) receives the slewing action signal, the controller (50) controls the hydraulic oil through the pilot oil control valve (43) to have a first pressure; when the controller (50) receives the luffing drop action signal, the controller (50) controls the hydraulic oil through the pilot oil control valve (43) to have a second pressure; when the controller (50) simultaneously receives the slewing action signal and the luffing drop action signal, the controller (50) controls the hydraulic oil through the pilot oil control valve (43) to have a third pressure; when the controller (50) does not receive the slewing action signal and / or the luffing drop action signal, the controller (50) controls the hydraulic oil through the pilot oil control valve (43) to have a fourth pressure; wherein, the first pressure is less than the second pressure, the third pressure is greater than or equal to the second pressure, and the fourth pressure is less than the first pressure.

10. The hydraulic control operation method for engineering machinery as described in claim 9, characterized in that, The switching valve (42) has an electrically controlled terminal Y1, and the pilot oil control valve (43) has an electrically driven terminal Y. S1 ; When the controller (50) controls the electrical control terminal Y1 of the switching valve (42) and the electrical drive terminal Y of the pilot oil control valve (43) S1 When there is no power, the first oil circuit (101) is open; When the controller (50) controls the electrical control terminal Y1 of the switching valve (42) to be energized, a current value I1 is simultaneously input to the electrical drive terminal Y of the pilot oil control valve (43). S1 At this time, the hydraulic oil has the fourth pressure through the pilot oil control valve (43); When the controller (50) controls the electrical control terminal Y1 of the switching valve (42) to be energized, a current value I2 is simultaneously input to the electrical drive terminal Y of the pilot oil control valve (43). S1 At this time, the hydraulic oil has the first pressure through the pilot oil control valve (43); When the controller (50) controls the electrical control terminal Y1 of the switching valve (42) to be energized, a current value I3 is simultaneously input to the electrical drive terminal Y of the pilot oil control valve (43). S1 At this time, the hydraulic oil has the second pressure through the pilot oil control valve (43); When the controller (50) controls the electrical control terminal Y1 of the switching valve (42) to be energized, a current value I4 is simultaneously input to the electrical drive terminal Y of the pilot oil control valve (43). S1 At this time, the hydraulic oil has the third pressure through the pilot oil control valve (43); Among them, the current values ​​I4 ≥ I3 > I2 > I1.

11. An engineering machinery, characterized in that, Includes the liquid control operating system as described in any one of claims 1 to 8.

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