CN118346672A - Hydraulic control system, method and engineering machinery - Google Patents
Hydraulic control system, method and engineering machinery Download PDFInfo
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- CN118346672A CN118346672A CN202410624157.5A CN202410624157A CN118346672A CN 118346672 A CN118346672 A CN 118346672A CN 202410624157 A CN202410624157 A CN 202410624157A CN 118346672 A CN118346672 A CN 118346672A
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- 238000000034 method Methods 0.000 title claims abstract description 13
- 238000010276 construction Methods 0.000 claims description 4
- 238000006073 displacement reaction Methods 0.000 claims 1
- 230000001105 regulatory effect Effects 0.000 abstract description 5
- 239000003921 oil Substances 0.000 description 42
- 230000001276 controlling effect Effects 0.000 description 7
- 239000010720 hydraulic oil Substances 0.000 description 7
- 230000001502 supplementing effect Effects 0.000 description 7
- 230000000007 visual effect Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
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Abstract
The invention relates to a hydraulic system, in order to solve the problem that the existing hydraulic system of the accessory needs to be provided with a flow regulating valve to regulate the flow of the accessory, the invention constructs a hydraulic control system, a method and engineering machinery, wherein the system comprises an accessory hydraulic executive component, a load sensitive accessory main valve, an electromagnetic reversing driving mechanism, a controller, an electric control handle, a hydraulic pump and an instrument; the instrument is used for inputting a flow limit value required by the work of the hydraulic executive component of the accessory, the controller determines a reversing current limit value according to the flow limit value input by the instrument, and outputs a reversing control current which is not more than the reversing current limit value to the electromagnetic reversing driving mechanism according to an operation electric signal of the electric control handle. According to the invention, the adjustment of the flow of the accessory can be satisfied on the engineering machinery without arranging a flow adjusting valve specially adjusting the flow at the oil inlet end of the main valve of the accessory.
Description
Technical Field
The present disclosure relates to hydraulic systems, and more particularly, to hydraulic control systems, methods, and work machines.
Background
The hydraulic actuators in the working device of the engineering machinery are usually driven by the hydraulic actuators, the engineering machinery needs to replace corresponding actuators to complete different works, each of the actuators has respective maximum working flow, the maximum output flow provided by the hydraulic pump arranged on the engineering machinery can be matched with each of the actuators, and for part of the actuators, the maximum output flow of the hydraulic pump is greatly larger than the maximum flow of the work of the actuators, and at the moment, the hydraulic flow supplied to the actuators needs to be adjusted to enable the hydraulic flow to be matched with the hydraulic pump.
In a conventional flow control system for an attachment of a construction machine, a flow control valve group is usually disposed in front of a valve of the attachment control valve, and a maximum flow rate to the attachment is regulated by the flow control valve group. The flow control system of the accessory has low flow adjustment precision, is difficult to realize ideal output flow, and can not automatically judge whether the current engine gear meets the manually set flow.
Disclosure of Invention
The invention aims to solve the technical problem that the existing hydraulic system of an accessory needs to be provided with a flow regulating valve to regulate the flow of the accessory, and provides a hydraulic control system, a hydraulic control method and engineering machinery.
The technical scheme for achieving the purpose of the invention is as follows: the hydraulic control system comprises an accessory hydraulic actuator, a load sensitive accessory main valve for controlling the accessory hydraulic actuator, an electromagnetic reversing driving mechanism for controlling the reversing of the accessory main valve, a controller for outputting reversing control current to the electromagnetic reversing driving mechanism, an electric control handle electrically connected with the controller, a hydraulic pump connected with an oil inlet of the accessory main valve, and a meter in communication electrical connection with the controller; the instrument is used for inputting a flow limit value required by the operation of the hydraulic executive component of the accessory, the controller determines a reversing current limit value according to the flow limit value input by the instrument, and outputs a reversing control current which is not more than the reversing current limit value to the electromagnetic reversing driving mechanism according to an operation electric signal of the electric control handle. The flow limit is the maximum flow allowed by the hydraulic actuator of the accessory when it is operating normally.
In the hydraulic control system of the present invention, the controller determines the output commutation control current I 0 according to equation (1),
Wherein I 1 is a commutation current limit determined by the controller from the flow limit input by the meter;
I 2 is a reversing control current value determined by the controller only according to an operation signal of the electric control handle when the electric control handle swings to the maximum amplitude;
I 3 is the reversing control current value determined by the controller only according to the operation signal of the electric control handle when the electric control handle swings to the current amplitude.
In the hydraulic control system, the instrument comprises an input module for inputting the flow limit value of the hydraulic actuating part of the accessory and a display module for displaying the flow limit value input by the input module.
In the hydraulic control system, the hydraulic pump is a gear pump, a gear control device of an engine for driving the hydraulic pump is electrically connected with the controller, and the controller displays the output flow range of the hydraulic pump corresponding to the current working gear of the engine according to the setting on the display module.
In the hydraulic control system, the instrument further comprises an alarm module, and the alarm module sends alarm information when the flow limit value input by the input module is out of the range of the outputtable flow of the hydraulic pump.
In the hydraulic control system, the control system further comprises a bypass valve, wherein an oil inlet and an oil outlet of the bypass valve are respectively communicated with the hydraulic pump and the hydraulic oil tank, the main valve of the accessory comprises a main valve core and a pressure compensation valve, and a spring cavity of the bypass valve is communicated with an oil outlet end of the pressure compensation valve.
In the hydraulic control system, the electromagnetic reversing driving mechanism is an electromagnet which is arranged on the main valve of the accessory and directly drives the valve core of the main valve of the accessory to move and reverse; or the electromagnetic reversing driving mechanism is an electric proportional valve pilot valve with a pilot oil port connected with the hydraulic control end of the main valve of the accessory, and an oil inlet of the electric proportional valve pilot valve is communicated with a pilot pressure oil source.
The technical scheme for achieving the purpose of the invention is as follows: the hydraulic control method is applied to an electrically controlled accessory hydraulic system in engineering machinery, and comprises the following steps:
the instrument inputs the flow limit value required by the work of the hydraulic executive component of the accessory;
The controller determines a reversing current limit value according to the flow limit value input by the instrument and outputs reversing control current which is not more than the reversing current limit value to an electromagnetic reversing driving mechanism for reversing the main valve of the control accessory according to an operation electric signal of the electric control handle.
In the hydraulic control method of the present invention, the controller determines the output commutation control current I 0 according to the formula (1),
Wherein I 1 is the commutation current limit value determined by the controller according to the flow limit value input by the instrument;
I 2 is a reversing control current value determined by the controller only according to an operation signal of the electric control handle when the electric control handle swings to the maximum amplitude;
I 3 is the reversing control current value determined by the controller only according to the operation signal of the electric control handle when the electric control handle swings to the current amplitude.
In the hydraulic control method, a controller acquires gear information of an engine driving a hydraulic pump, determines and displays an outputtable flow range of the hydraulic pump on an instrument according to the gear information of the engine, and sends out alarm information when a flow limit value input by the instrument is out of the outputtable flow range of the hydraulic pump.
The technical scheme for achieving the purpose of the invention is as follows: a construction machine is provided having the hydraulic control system described above.
Compared with the prior art, the controller controls the electromagnetic reversing driving mechanism for controlling the reversing of the main valve of the accessory to control the flow of the hydraulic actuating part of the accessory, a flow regulating valve special for regulating the flow is not required to be arranged at the oil inlet end of the main valve of the accessory, and the regulation of the flow of the accessory is satisfied on the existing configuration of engineering machinery.
Drawings
Fig. 1 is a schematic diagram of a hydraulic control system of the present invention.
Part names and serial numbers in the figure:
The hydraulic pump 1, the instrument 2, the controller 3, the electric control handle 4, the bypass valve 5, the electromagnetic reversing driving mechanism 6, the main valve 7 of the accessory, the main valve core 8, the pressure compensation valve 9, the first oil supplementing overflow valve 10, the second oil supplementing overflow valve 11, the hydraulic actuating part 12 of the accessory, the main overflow valve 13, the hydraulic oil tank 14 and the gear control device 15.
Detailed Description
The following describes specific embodiments with reference to the drawings.
As shown in fig. 1, in the present embodiment, the hydraulic control system includes an attachment hydraulic actuator 12, a load-sensitive attachment main valve 7 for controlling the attachment hydraulic actuator 12, an electromagnetic directional drive mechanism 6 for controlling the directional of the attachment main valve 7, a controller 3 for outputting a directional control current to the electromagnetic directional drive mechanism 6, an electric control handle 4 electrically connected to the controller 3, a hydraulic pump 1 connected to an oil inlet of the attachment main valve 7, and an instrument communicatively and electrically connected to the controller 3; the instrument 2 is used for inputting a flow limit value required by the operation of the hydraulic executive component 12 of the set accessory, the controller 3 determines a reversing current limit value according to the flow limit value input by the instrument, and outputs a reversing control current which is not more than the reversing current limit value to the electromagnetic reversing driving mechanism 6 according to an operation electric signal of the electric control handle 4.
In this embodiment, the attachment main valve 7 is a load-sensitive control valve, and the flow through the attachment main valve 7 to the attachment hydraulic actuator 12 is related to the opening of the attachment main valve 7. In this embodiment, the maximum opening of the main valve 7 of the attachment is defined by setting a flow limit value via the input of the meter 2 and determining a commutation current limit value in this way, so that the flow to the attachment hydraulic actuator 12 does not exceed the maximum flow required for the operation of the attachment hydraulic actuator 12.
The two connecting oil ports of the main valve 7 of the accessory and the two connecting oil paths between the hydraulic actuating part 12 of the accessory are correspondingly provided with a first oil supplementing overflow valve 10 and a second oil supplementing overflow valve 11, and the oil outlet ends of the first oil supplementing overflow valve 10 and the second oil supplementing overflow valve 11 are communicated with a hydraulic oil tank 14. The oil-supplementing overflow valve is composed of a one-way valve and an overflow valve which are connected in parallel, and has the functions of overload protection and oil supplementing.
The main valve 7 of the accessory comprises a main valve core 8 and a pressure compensation valve 9, wherein the pressure compensation valve 9 is used for compensating the pressure change generated by the load change, so that the pressure difference of an oil inlet and an oil outlet of the main valve core 8 is constant, and the pressure compensation valve 9 is used for adjusting the flow passing through the main valve core 8, so that the flow passing through the main valve core 8 is only related to the opening of the main valve core 8.
The oil inlet and outlet of the bypass valve 5 are respectively communicated with the hydraulic pump 1 and the hydraulic oil tank 14, and the spring cavity of the bypass valve 5 is communicated with the oil outlet end of the pressure compensation valve 9. When the main valve core 8 is in a neutral state, the oil outlet end of the pressure compensating valve 9 does not have pressure oil output, and the bypass valve 5 is opened under the action of the pressure oil of the oil inlet, so that the pressure relief of the pressure oil of the hydraulic pump 1 is realized. When the main valve core 8 is reversed, the oil outlet end of the pressure compensating valve 9 has pressure oil output, the pressure of the pressure oil acts on the spring cavity of the bypass valve 5, the hydraulic oil pressure of the spring cavity of the bypass valve 5 plus the spring force is larger than the pressure output by the hydraulic pump 1, the bypass valve 5 is in a closed state, and the redundant flow overflows from the main overflow valve 13.
The oil inlet end of the main overflow valve 13 is communicated with the oil outlet end of the pressure compensation valve 9, and the oil outlet end of the main overflow valve 13 is communicated with the hydraulic oil tank 14. The main relief valve 13 opens to relieve pressure when the main spool is in the reversing position and the pressure is higher than the set pressure, defining the highest pressure of the system.
Optionally, the controller 3 determines the output commutation control current I 0 according to equation (1). The formula (1) is as follows:
Wherein I 1 is the commutation current limit determined by the controller 3 from the flow value input by the meter 2; when the current I 1 is input to the electromagnetic reversing driving mechanism 6, the opening of the main valve core 8 reaches the corresponding opening degree, and under the condition that the flow output by the hydraulic pump 1 is enough, the flow output by the main valve core 8 under the opening can reach the maximum flow required by the operation of the hydraulic executive component of the accessory.
I 2 is a reversing control current value determined by the controller 3 only according to an operation signal of the electric control handle 4 when the electric control handle 4 swings to the maximum amplitude; the electric control handle 4 swings from the middle position to the initial position, and as the swing amplitude of the electric control handle 4 increases, the larger the value corresponding to the operation signal (usually current or voltage) output by the electric control handle 4 to the controller 3, the controller 3 determines the reversing control current to be output according to the operation signal of the electric control handle 4. I 2 is a commutation control current value determined by the controller 3 only according to the operation signal of the electric control handle 4 when the electric control handle 4 swings to the maximum amplitude without considering the limitation of the magnitude of the commutation control current, that is, the maximum commutation control current that the controller 3 can output according to the operation signal.
I 3 is a commutation control current value determined by the controller 3 only according to an operation signal of the electric control handle when the electric control handle 4 swings to a current amplitude.
The controller 3 determines the output commutation control current I 0 according to the formula (1), when the electric control handle 4 swings to the maximum amplitude, the commutation control current output by the controller 3 is equal to the commutation current limit value, so that the electric control handle 4 is controlled to still be in full-stroke operation under the condition that the magnitude of the commutation control current is limited by the commutation current limit value.
Optionally, the meter 2 comprises an input module for inputting a flow value of the hydraulic actuator of the accessory, and a display module for displaying the flow value input by the input module. The input module and the display module may be constituted by a touch display or by a display and an adjustment knob. The flow value is input through a touch display or an adjusting knob, and is intuitively displayed on the display, so that the flow adjusting operation is convenient.
Optionally, the hydraulic pump 1 is a gear pump, and the gear control device 15 of the engine driving the hydraulic pump 1 is electrically connected to the controller 3, and the controller 3 displays the output flow range of the hydraulic pump corresponding to the current working gear of the engine according to the setting on the display module. Further, the meter 2 further comprises an alarm module, and the alarm module sends out alarm information when the flow value input by the input module is out of the range of the output flow of the hydraulic pump.
The output flow of the gear pump is related to its rotational speed, i.e. to the engine gear in which the hydraulic pump 1 is driven to operate. The controller 3 is electrically connected with a gear control device 15 of the engine, obtains the gear of the engine, and displays the flow range (the maximum flow and the minimum flow which can be provided by the hydraulic pump in the current gear) on the display module according to the gear of the engine, so that an operator can intuitively judge whether the flow output by the hydraulic pump 1 can meet the flow requirement of the hydraulic executive component of the accessory. If the flow value input by the operator is larger than the upper limit value of the flow range displayed on the display module, the current output flow of the hydraulic pump 1 is indicated to be incapable of meeting the flow requirement of the hydraulic executive component 12 of the accessory, and the alarm module prompts the operator to adjust the gear of the engine or confirms whether the input flow value is correct by sending out audible and visual alarm information; an operator can increase the output flow of the hydraulic pump 1 by increasing the engine gear to meet the flow demand of some high-flow accessory hydraulic actuators 12. If the flow value input by the operator is smaller than the lower limit value of the flow range displayed on the display module, the flow value input by the operator indicates that the current output flow of the hydraulic pump 1 is too surplus for the flow required by the normal operation of the accessory hydraulic executing piece 12, and the operator can reduce the output flow of the hydraulic pump by reducing the gear of the engine, so that the energy saving of the engineering machinery is realized.
The gear control device 15 may be constituted by an engine control unit or by an engine gear knob. The controller 3 may directly acquire the engine speed from the engine control unit to determine its gear and thus determine the output flow rate of the hydraulic pump, or the controller 3 may acquire gear information from the engine gear knob to determine the output flow rate of the hydraulic pump 1.
Alternatively, the electromagnetic reversing driving mechanism 6 may be an electromagnet arranged on the main valve 7 of the accessory to directly drive the valve rod of the main valve core to move and reverse; or the electromagnetic reversing driving mechanism 6 is an electric proportional valve pilot valve with a pilot oil port connected with the hydraulic control end of the main valve of the accessory, and an oil inlet of the electric proportional valve pilot valve is communicated with a pilot pressure oil source. The pilot pressure oil source may be a pilot pump or a pilot oil supply valve that reduces the pressure of the high-pressure hydraulic oil in the hydraulic system to obtain low-pressure pilot pressure oil for pilot control.
The embodiment provides a hydraulic control method, which is applied to an electrically controlled accessory hydraulic system in engineering machinery, wherein the accessory hydraulic system comprises an accessory hydraulic executing part 12, a load sensitive accessory main valve 7 for controlling the accessory hydraulic executing part 12, an electromagnetic reversing driving mechanism 6 for controlling reversing of the accessory main valve 7, a controller 3 for outputting reversing control current to the electromagnetic reversing driving mechanism 6, an electric control handle 4 electrically connected with the controller 3, a hydraulic pump 1 connected with an oil inlet of the accessory main valve 7, and an instrument 2 in communication electrical connection with the controller 3.
The hydraulic control method comprises the following steps:
the instrument 2 inputs the maximum flow value required by the work of the hydraulic executive component of the accessory;
The controller 3 determines a commutation current limit value according to the flow value input by the meter 2 and outputs a commutation control current not greater than the commutation current limit value to the electromagnetic commutation driving mechanism 6 which commutates the control attachment main valve 7 according to the operation electric signal of the electric control handle 4.
Further, the controller 3 determines the output commutation control current I 0 according to equation (1). Alternatively, the controller 3 acquires gear information of an engine driving the hydraulic pump 1, determines and displays an outputtable flow range of the hydraulic pump 1 on the meter 2 according to the gear information of the engine, and issues an alarm message when a flow value inputted by the meter 2 is out of the outputtable flow range of the hydraulic pump.
If the flow value input by the instrument 2 is larger than the upper limit value of the flow range displayed on the display module, prompting an operator to adjust the gear of the engine or confirming whether the input flow value is correct by sending out audible and visual alarm information; the operator may re-input the flow value or increase the output flow of the hydraulic pump by increasing the engine gear. If the flow value input by the instrument 2 is smaller than the lower limit value of the flow range displayed by the display module, an operator can reduce the output flow of the hydraulic pump by reducing the gear of the engine, so that the energy saving of the engineering machinery is realized.
The embodiment provides a construction machine, which is provided with the hydraulic control system. The work machine may be a loader or an excavator.
In this embodiment, the flow adjustment can be performed according to the input flow value without setting a flow adjusting valve for adjusting the flow specially at the oil inlet end of the main valve of the accessory, so that the flow output by the main valve of the accessory meets the flow requirement of the accessory, and the hydraulic control system is prevented from increasing hydraulic devices due to the need of adjusting the flow.
Claims (10)
1. The hydraulic control system comprises an accessory hydraulic execution part, a load sensitive accessory main valve for controlling the accessory hydraulic execution part, an electromagnetic reversing driving mechanism for controlling the reversing of the accessory main valve, a controller for outputting reversing control current to the electromagnetic reversing driving mechanism, an electric control handle electrically connected with the controller, and a hydraulic pump connected with an oil inlet of the accessory main valve, and is characterized by further comprising an instrument electrically connected with the controller in a communication way; the instrument is used for inputting a flow limit value required by the operation of the hydraulic executive component of the accessory, the controller determines a reversing current limit value according to the flow limit value input by the instrument, and outputs a reversing control current which is not more than the reversing current limit value to the electromagnetic reversing driving mechanism according to an operation electric signal of the electric control handle.
2. The hydraulic control system of claim 1, wherein the controller determines the output commutation control current I 0 according to equation (1),
Wherein I 1 is a commutation current limit determined by the controller from the flow limit input by the meter;
I 2 is a reversing control current value determined by the controller only according to an operation signal of the electric control handle when the electric control handle swings to the maximum amplitude;
I 3 is the reversing control current value determined by the controller only according to the operation signal of the electric control handle when the electric control handle swings to the current amplitude.
3. The hydraulic control system of claim 1 or 2, wherein the meter comprises an input module for inputting a flow limit value of the hydraulic implement of the accessory, and a display module for displaying the flow limit value input by the input module.
4. The hydraulic control system according to claim 3, wherein the hydraulic pump is a gear pump, and a gear control device of an engine driving the hydraulic pump is electrically connected to the controller, and the controller displays an outputtable flow range of the hydraulic pump corresponding to a current operating gear of the engine according to a setting on the display module.
5. The hydraulic control system of claim 4, wherein the meter further comprises an alarm module that issues an alarm message when the flow limit entered by the input module is outside of the range of the outputtable flow of the hydraulic pump.
6. The hydraulic control system of claim 1, further comprising a bypass valve having an oil inlet and an oil outlet in communication with the hydraulic pump and the hydraulic tank, respectively, the attachment main valve comprising a main spool and a pressure compensating valve, a spring chamber of the bypass valve in communication with an oil outlet of the pressure compensating valve.
7. The hydraulic control method is applied to an electrically controlled accessory hydraulic system in engineering machinery and is characterized by comprising the following steps:
the instrument inputs the flow limit value required by the work of the hydraulic executive component of the accessory;
the controller determines a reversing current limit value according to the flow limit value input by the instrument and outputs reversing control current which is not more than the reversing current limit value to the electromagnetic reversing driving mechanism for controlling the main valve of the accessory to reverse according to the operation electric signal of the electric control handle.
8. The hydraulic control method according to claim 7, wherein the controller determines the output commutation control current I 0 according to equation (1),
Wherein I 1 is the commutation current limit value determined by the controller according to the flow limit value input by the instrument;
I 2 is a reversing control current value determined by the controller only according to an operation signal of the electric control handle when the electric control handle swings to the maximum amplitude;
I 3 is the reversing control current value determined by the controller only according to the operation signal of the electric control handle when the electric control handle swings to the current amplitude.
9. The hydraulic control method according to claim 7 or 8, wherein the hydraulic pump is a fixed displacement pump, the controller obtains gear information of an engine that drives the hydraulic pump, determines and displays an outputtable flow range of the hydraulic pump on the meter according to the gear information of the engine, and the meter issues an alarm message when a flow limit value input by the meter is outside the outputtable flow range of the hydraulic pump.
10. A construction machine characterized by having the hydraulic control system according to any one of claims 1 to 6.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410624157.5A CN118346672A (en) | 2024-05-20 | 2024-05-20 | Hydraulic control system, method and engineering machinery |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410624157.5A CN118346672A (en) | 2024-05-20 | 2024-05-20 | Hydraulic control system, method and engineering machinery |
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| Publication Number | Publication Date |
|---|---|
| CN118346672A true CN118346672A (en) | 2024-07-16 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202410624157.5A Pending CN118346672A (en) | 2024-05-20 | 2024-05-20 | Hydraulic control system, method and engineering machinery |
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| Country | Link |
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| CN (1) | CN118346672A (en) |
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2024
- 2024-05-20 CN CN202410624157.5A patent/CN118346672A/en active Pending
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