CN114215797B - Method for controlling flow of variable pump by hydraulic system - Google Patents
Method for controlling flow of variable pump by hydraulic system Download PDFInfo
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- CN114215797B CN114215797B CN202111349790.0A CN202111349790A CN114215797B CN 114215797 B CN114215797 B CN 114215797B CN 202111349790 A CN202111349790 A CN 202111349790A CN 114215797 B CN114215797 B CN 114215797B
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- hydraulic
- oil
- variable
- flow
- oil port
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- 238000000034 method Methods 0.000 title claims abstract description 18
- 239000003921 oil Substances 0.000 claims description 137
- 239000010720 hydraulic oil Substances 0.000 claims description 44
- 238000006073 displacement reaction Methods 0.000 claims description 26
- 230000008602 contraction Effects 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 1
Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
- F15B11/02—Systems essentially incorporating special features for controlling the speed or actuating force of an output member
- F15B11/04—Systems essentially incorporating special features for controlling the speed or actuating force of an output member for controlling the speed
- F15B11/042—Systems essentially incorporating special features for controlling the speed or actuating force of an output member for controlling the speed by means in the feed line, i.e. "meter in"
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
- F15B2211/205—Systems with pumps
- F15B2211/2053—Type of pump
- F15B2211/20546—Type of pump variable capacity
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
- F15B2211/255—Flow control functions
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Fluid-Pressure Circuits (AREA)
Abstract
The method for controlling the flow of the variable pump by the hydraulic system comprises a main oil way and a flow control system, wherein the main oil way comprises a small-flow signal oil port and a large-flow signal oil port, and the pressure of the large-flow signal oil port is larger than that of the small-flow signal oil port; the flow control system comprises a shuttle valve, a pressure reducing valve, a hydraulic reversing valve, a variable hydraulic pump and an oil tank; one input end of the shuttle valve is connected with a small-flow signal oil port, the other input end of the shuttle valve is connected with a large-flow signal oil port, the output end of the shuttle valve is connected with the input end of the pressure reducing valve, the output end of the pressure reducing valve is connected with a signal oil port of the hydraulic reversing valve, the input end of the hydraulic reversing valve is connected with an oil tank, the output end of the hydraulic reversing valve is connected with a signal oil port of the variable reversing pump, the input end of the variable reversing pump is connected with the oil tank, and the output end of the variable reversing pump is connected with an input oil port of a main oil way; the invention meets the use requirement of larger flow difference required between different actions, and the situation that the flow overflows and heats is avoided; the cost is lower.
Description
Technical Field
The invention relates to the technical field of hydraulic pressure, in particular to a method for controlling the flow of a variable pump by a hydraulic system.
Background
With the improvement of the operation efficiency requirement of the crane by the user, the oil pump is required to provide enough flow to meet the system requirement; however, when the flow required by one action of the crane is much larger than the flow required by other actions, the small flow action can overflow to generate great heat due to the surplus flow when the quantitative pump system is used, so that the design and use requirements can not be met; although the oil pump output is only related to the opening of the multi-way valve of the flow required by the action when the load sensitive variable system is used, and no excessive flow overflows and heats, the problems can be solved, but the system control is complex and the element cost is high when the load sensitive variable system is used.
For the telescopic actions of some telescopic cranes, the hydraulic flow difference required before and after the telescopic actions of the cranes is larger, so that a hydraulic system with low cost and meeting the use requirement of larger flow difference required between different actions is required to be designed.
Disclosure of Invention
The invention provides a method for controlling the flow of a variable pump by a hydraulic system, which meets the use requirement of larger flow difference required by different actions and does not generate heat due to overflow of more flow; the cost is lower.
In order to achieve the above purpose, the technical scheme of the invention is as follows: the method for controlling the flow of the variable pump by the hydraulic system comprises a main oil way and a flow control system, wherein the main oil way comprises a small-flow signal oil port, a large-flow signal oil port and a main oil way input oil port, and the pressure of the large-flow signal oil port is larger than that of the small-flow signal oil port.
The flow control system comprises a shuttle valve, a pressure reducing valve, a hydraulic reversing valve, a variable hydraulic pump and an oil tank; one input end of the shuttle valve is connected with a small-flow signal oil port, the other input end of the shuttle valve is connected with a large-flow signal oil port, the output end of the shuttle valve is connected with the input end of the pressure reducing valve, the output end of the pressure reducing valve is connected with a signal oil port of the hydraulic reversing valve, the input end of the hydraulic reversing valve is connected with an oil tank, the output end of the hydraulic reversing valve is connected with a signal oil port of the variable hydraulic pump, the input end of the variable hydraulic pump is connected with the oil tank, and the output end of the variable hydraulic pump is connected with an input oil port of a main oil way.
When the small-flow signal oil port outputs hydraulic oil, the oil pressure of the small-flow signal oil port is insufficient to change the direction of the hydraulic reversing valve; when the hydraulic oil is output by the large-flow signal oil port, the hydraulic oil of the large-flow signal oil port is processed by the pressure reducing valve, so that the hydraulic reversing valve reverses.
The method for controlling the flow of the variable pump by the hydraulic system comprises the following steps:
(1) When the small-flow signal oil port outputs hydraulic oil, the oil pressure of the small-flow signal oil port is insufficient to enable the hydraulic reversing valve to change direction, and the variable hydraulic pump discharges the variable-displacement hydraulic oil.
(2) When the hydraulic oil is output by the large-flow signal oil port, the hydraulic oil of the large-flow signal oil port is processed by the pressure reducing valve, so that the hydraulic reversing valve reverses.
(3) The hydraulic oil of the hydraulic reversing valve is used as signal oil to be transmitted to the variable hydraulic pump, and the variable hydraulic pump outputs the hydraulic oil in a variable displacement mode.
According to the method, when the small-flow signal oil port outputs hydraulic oil, the oil pressure of the small-flow signal oil port is insufficient to change the direction of the hydraulic reversing valve, and the variable hydraulic pump discharges the variable-displacement hydraulic oil at the moment; when the large-flow signal oil port outputs hydraulic oil, the hydraulic oil of the large-flow signal oil port is processed by the pressure reducing valve, so that the hydraulic oil of the hydraulic reversing valve is used as signal oil to be conveyed to the variable hydraulic pump, and the variable hydraulic pump carries out variable displacement output of the hydraulic oil at the moment, so that the variable hydraulic pump automatically switches the flow of the hydraulic variable pump according to the required hydraulic flow of a main oil path loaded by a hydraulic system to be conveyed to an input oil port of the main oil path, the requirement of the main oil path on large-flow action is met, and the system generates overflow heating when the main oil path does not carry out small-flow action.
Further, the hydraulic reversing valve is a two-position two-way hydraulic reversing valve.
Further, when the large-flow signal oil port is output, the pressure of the output end of the pressure reducing valve is larger than the pressure required by reversing of the hydraulic reversing valve; after receiving the signal oil output by the pressure reducing valve, the hydraulic reversing valve reverses according to the pressure of the signal oil and then outputs hydraulic oil to the variable hydraulic pump so as to change the hydraulic oil to large displacement; when the expansion and contraction do not act, the hydraulic reversing valve is not subjected to reversing pressure, the hydraulic reversing valve is reset under the action of the spring, the variable hydraulic pump is controlled to discharge variable-displacement oil, and the oil pump is controlled to be low-displacement.
Further, the variable hydraulic pump is a one-way variable hydraulic pump.
Further, the power source of the variable hydraulic pump is an electric motor.
Further, an oil drain port of the hydraulic reversing valve is connected with an oil tank.
Drawings
FIG. 1 is a block diagram of a main oil circuit and flow control system connection of the present invention.
Description of the drawings: 1. a main oil path; 11. a large-flow signal oil port; 12. a small flow signal oil port; 13. an oil inlet of the main oil way; 2. a shuttle valve; 3. a pressure reducing valve; 4. a hydraulic reversing valve; 5. a variable displacement hydraulic pump.
Detailed Description
The invention is described in further detail below with reference to the drawings and the detailed description.
As shown in fig. 1, a method for controlling the flow of a variable pump by a hydraulic system comprises a main oil path 1 and a flow control system, wherein the main oil path 1 is used for controlling a telescopic hydraulic cylinder, the main oil path 1 comprises a small flow signal oil port 12, a large flow signal oil port 11 and a main oil path 1 input oil port, and the pressure of the large flow signal oil port 11 is larger than that of the small flow signal oil port 12.
The flow control system comprises a shuttle valve 2, a pressure reducing valve 3, a hydraulic reversing valve 4, a variable hydraulic pump 5 and an oil tank; one input end of the shuttle valve 2 is connected with a small-flow signal oil port 12, the other input end of the shuttle valve 2 is connected with a large-flow signal oil port 11, the output end of the shuttle valve 2 is connected with the input end of the pressure reducing valve 3, the output end of the pressure reducing valve 3 is connected with a signal oil port of the hydraulic reversing valve 4, the input end of the hydraulic reversing valve 4 is connected with an oil tank, the output end of the hydraulic reversing valve 4 is connected with a signal oil port of the variable hydraulic pump, the input end of the variable hydraulic pump is connected with the oil tank, and the output end of the variable hydraulic pump is connected with a main oil path input oil port 13.
When the telescopic hydraulic cylinder performs telescopic action, the large-flow signal oil port 11 outputs signal oil to enter the shuttle valve 2; when the telescopic hydraulic cylinder does not perform telescopic action, the small-flow signal oil port 12 outputs signal oil to enter the shuttle valve 2; when the small-flow signal oil port 12 outputs hydraulic oil, the oil pressure of the small-flow signal oil port 12 is insufficient to change the direction of the hydraulic reversing valve 4; when the large-flow signal oil port 11 outputs hydraulic oil, the hydraulic oil of the large-flow signal oil port 11 is processed by the pressure reducing valve 3, so that the hydraulic reversing valve 4 reverses; the hydraulic flow rate at the time of the telescopic operation of the crane is about 3 times the hydraulic flow rate of the other operations, and it is determined whether the telescopic operation is performed by the shuttle valve 2, so that the signal oil is outputted by the shuttle valve 2.
The method for controlling the flow of the variable pump by the hydraulic system comprises the following steps:
(1) When the small-flow signal oil port outputs hydraulic oil, the oil pressure of the small-flow signal oil port is insufficient to change the direction of the hydraulic reversing valve, and the variable hydraulic pump discharges the variable-displacement hydraulic oil at the moment;
(2) When the hydraulic oil is output from the large-flow signal oil port, the hydraulic oil of the large-flow signal oil port is processed by the pressure reducing valve, so that the hydraulic reversing valve is reversed;
(3) The hydraulic oil of the hydraulic reversing valve is used as signal oil to be transmitted to the variable hydraulic pump, and the variable hydraulic pump outputs the hydraulic oil in a variable displacement mode.
According to the method, when the small-flow signal oil port 12 outputs hydraulic oil, the oil pressure of the small-flow signal oil port 12 is insufficient to change the direction of the hydraulic reversing valve 4, and the variable hydraulic pump 5 discharges the variable-displacement hydraulic oil; when the large-flow signal oil port 11 outputs hydraulic oil, the hydraulic oil of the large-flow signal oil port 11 is processed by the pressure reducing valve 3, so that the hydraulic oil of the hydraulic reversing valve 4 is reversed, the hydraulic oil passing through the hydraulic reversing valve 4 is further used as signal oil to be conveyed to the variable hydraulic pump 5, and the variable hydraulic pump 5 carries out variable displacement output hydraulic oil at the moment, so that the variable hydraulic pump 5 automatically switches the flow of the hydraulic variable pump according to the required hydraulic flow of the main oil path 1 loaded by a hydraulic system and conveys the flow to the main oil path input oil port 13, the requirement of the main oil path 1 for large-flow action is met, and the overflow heating of a system is not caused when the main oil path 1 carries out small-flow action.
The hydraulic reversing valve 4 is a two-position two-way hydraulic reversing valve 4.
When the large-flow signal oil port 11 is output, the pressure of the output end of the pressure reducing valve 3 is larger than the pressure required by reversing of the hydraulic reversing valve 4; the pressure set by the pressure reducing valve 3 is 35bar, and the reversing pressure of the hydraulic reversing valve 4 is 14bar; the hydraulic reversing valve 4 reverses according to the pressure of the signal oil after receiving the signal oil output by the pressure reducing valve 3, and then outputs hydraulic oil to the variable displacement hydraulic pump 5 to change the hydraulic oil to large displacement; when the expansion and contraction do not act, the hydraulic reversing valve 4 is not subjected to pressure for reversing the hydraulic reversing valve, the hydraulic reversing valve 4 is reset under the action of a spring, the variable hydraulic pump 5 is controlled to discharge variable-displacement oil, and the oil pump is controlled to be low-displacement; this valve corresponds to an on-off valve that controls whether or not the variable displacement hydraulic pump 5 is variable.
The variable displacement hydraulic pump 5 is a unidirectional variable displacement hydraulic pump 5.
The power source of the variable hydraulic pump 5 is an electric motor.
The oil drain port of the hydraulic reversing valve 4 is connected with an oil tank.
Claims (6)
1. A method for controlling the flow of a variable pump by a hydraulic system is characterized by comprising the following steps of: the system comprises a main oil way and a flow control system, wherein the main oil way comprises a small-flow signal oil port, a large-flow signal oil port and a main oil way input oil port, and the pressure of the large-flow signal oil port is larger than that of the small-flow signal oil port;
The flow control system comprises a shuttle valve, a pressure reducing valve, a hydraulic reversing valve, a variable hydraulic pump and an oil tank; one input end of the shuttle valve is connected with a small-flow signal oil port, the other input end of the shuttle valve is connected with a large-flow signal oil port, the output end of the shuttle valve is connected with the input end of the pressure reducing valve, the output end of the pressure reducing valve is connected with a signal oil port of the hydraulic reversing valve, the input end of the hydraulic reversing valve is connected with an oil tank, the output end of the hydraulic reversing valve is connected with a signal oil port of the variable hydraulic pump, the input end of the variable hydraulic pump is connected with the oil tank, and the output end of the variable hydraulic pump is connected with an input oil port of a main oil way;
When the small-flow signal oil port outputs hydraulic oil, the oil pressure of the small-flow signal oil port is insufficient to change the direction of the hydraulic reversing valve; when the hydraulic oil is output from the large-flow signal oil port, the hydraulic oil of the large-flow signal oil port is processed by the pressure reducing valve, so that the hydraulic reversing valve is reversed;
the method for controlling the flow of the variable pump by the hydraulic system comprises the following steps:
(1) When the small-flow signal oil port outputs hydraulic oil, the oil pressure of the small-flow signal oil port is insufficient to change the direction of the hydraulic reversing valve, and the variable hydraulic pump discharges the variable-displacement hydraulic oil at the moment;
(2) When the hydraulic oil is output from the large-flow signal oil port, the hydraulic oil of the large-flow signal oil port is processed by the pressure reducing valve, so that the hydraulic reversing valve is reversed;
(3) The hydraulic oil of the hydraulic reversing valve is used as signal oil to be transmitted to the variable hydraulic pump, and the variable hydraulic pump outputs the hydraulic oil in a variable displacement mode.
2. A method of controlling variable displacement pump flow in a hydraulic system according to claim 1, wherein: the hydraulic reversing valve is a two-position two-way hydraulic reversing valve.
3. A method of controlling variable displacement pump flow in a hydraulic system according to claim 1, wherein: when the large-flow signal oil port is output, the pressure of the output end of the pressure reducing valve is larger than the pressure required by reversing of the hydraulic reversing valve.
4. A method of controlling variable displacement pump flow in a hydraulic system according to claim 1, wherein: the variable hydraulic pump is a one-way variable hydraulic pump.
5. A method of controlling variable displacement pump flow in a hydraulic system according to claim 1, wherein: the power source of the variable hydraulic pump is an electric motor.
6. A method of controlling variable displacement pump flow in a hydraulic system according to claim 1, wherein: the oil drain port of the hydraulic reversing valve is connected with an oil tank.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111349790.0A CN114215797B (en) | 2021-11-15 | 2021-11-15 | Method for controlling flow of variable pump by hydraulic system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111349790.0A CN114215797B (en) | 2021-11-15 | 2021-11-15 | Method for controlling flow of variable pump by hydraulic system |
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| CN114215797A CN114215797A (en) | 2022-03-22 |
| CN114215797B true CN114215797B (en) | 2024-04-19 |
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| CN202111349790.0A Active CN114215797B (en) | 2021-11-15 | 2021-11-15 | Method for controlling flow of variable pump by hydraulic system |
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Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5907951A (en) * | 1997-03-07 | 1999-06-01 | Hitachi Construction Machinery Co., Ltd. | Hydraulic control system for construction machine |
| JP2005060970A (en) * | 2003-08-08 | 2005-03-10 | Sumitomo (Shi) Construction Machinery Manufacturing Co Ltd | Hydraulic circuit for hydraulic excavator |
| JP2005299931A (en) * | 2005-04-21 | 2005-10-27 | Hitachi Constr Mach Co Ltd | Hydraulic control device for construction machinery |
| CN103526796A (en) * | 2013-09-25 | 2014-01-22 | 中外合资沃得重工（中国）有限公司 | Excavator breaking hammer hydraulic motor flow control device |
| CN105952700A (en) * | 2016-06-29 | 2016-09-21 | 徐工集团工程机械股份有限公司科技分公司 | Loader variable multi-stage power control module and hydraulic system |
| CN106593982A (en) * | 2017-01-04 | 2017-04-26 | 浙江高宇液压机电有限公司 | Logical control valve capable of realizing variable displacement of variable pump in combining and separating |
| CN106759621A (en) * | 2017-01-04 | 2017-05-31 | 浙江高宇液压机电有限公司 | Load-sensitive formula loading machine determines variable delivery hydraulic system |
| CN107061392A (en) * | 2017-06-06 | 2017-08-18 | 山东建筑大学 | Mechanical arm hydraulic control circuit and method of operating |
| CN108105179A (en) * | 2017-11-09 | 2018-06-01 | 武汉船用机械有限责任公司 | A kind of hydraulic control system of Hawser winch |
| CN114151418A (en) * | 2021-11-15 | 2022-03-08 | 中船华南船舶机械有限公司 | Variable pump flow control hydraulic system |
| CN216922714U (en) * | 2021-11-15 | 2022-07-08 | 中船华南船舶机械有限公司 | Hydraulic system for controlling flow |
-
2021
- 2021-11-15 CN CN202111349790.0A patent/CN114215797B/en active Active
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5907951A (en) * | 1997-03-07 | 1999-06-01 | Hitachi Construction Machinery Co., Ltd. | Hydraulic control system for construction machine |
| JP2005060970A (en) * | 2003-08-08 | 2005-03-10 | Sumitomo (Shi) Construction Machinery Manufacturing Co Ltd | Hydraulic circuit for hydraulic excavator |
| JP2005299931A (en) * | 2005-04-21 | 2005-10-27 | Hitachi Constr Mach Co Ltd | Hydraulic control device for construction machinery |
| CN103526796A (en) * | 2013-09-25 | 2014-01-22 | 中外合资沃得重工（中国）有限公司 | Excavator breaking hammer hydraulic motor flow control device |
| CN105952700A (en) * | 2016-06-29 | 2016-09-21 | 徐工集团工程机械股份有限公司科技分公司 | Loader variable multi-stage power control module and hydraulic system |
| CN106593982A (en) * | 2017-01-04 | 2017-04-26 | 浙江高宇液压机电有限公司 | Logical control valve capable of realizing variable displacement of variable pump in combining and separating |
| CN106759621A (en) * | 2017-01-04 | 2017-05-31 | 浙江高宇液压机电有限公司 | Load-sensitive formula loading machine determines variable delivery hydraulic system |
| CN107061392A (en) * | 2017-06-06 | 2017-08-18 | 山东建筑大学 | Mechanical arm hydraulic control circuit and method of operating |
| CN108105179A (en) * | 2017-11-09 | 2018-06-01 | 武汉船用机械有限责任公司 | A kind of hydraulic control system of Hawser winch |
| CN114151418A (en) * | 2021-11-15 | 2022-03-08 | 中船华南船舶机械有限公司 | Variable pump flow control hydraulic system |
| CN216922714U (en) * | 2021-11-15 | 2022-07-08 | 中船华南船舶机械有限公司 | Hydraulic system for controlling flow |
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| CN114215797A (en) | 2022-03-22 |
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