CN104047665A - Control system for controlling single-action-cavity feedback variable-displacement vane pump by electromagnetic valve - Google Patents
Control system for controlling single-action-cavity feedback variable-displacement vane pump by electromagnetic valve Download PDFInfo
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- CN104047665A CN104047665A CN201410248741.1A CN201410248741A CN104047665A CN 104047665 A CN104047665 A CN 104047665A CN 201410248741 A CN201410248741 A CN 201410248741A CN 104047665 A CN104047665 A CN 104047665A
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Abstract
The invention provides a control system for controlling a single-action-cavity feedback variable-displacement vane pump by an electromagnetic valve. The control system comprises the single-action-cavity feedback variable-displacement vane pump, a pump outlet, a main oil duct, an oil pan, a safety valve, a main control valve and the switch type electromagnetic valve, wherein the single-action-cavity feedback variable-displacement vane pump comprises a pump body, vanes, a rotor, a feedback pressure oil chamber, a slider rotation locating pin, a variable slider and a variable spring. The main control valve is added on the structure of the single-action-cavity feedback variable-displacement vane pump, so two-stage variable displacement is realized, differential pressure control is realized by using the cross section difference between an upper end piston cavity and a lower end piston cavity of the main control valve, the structure is simpler than a double-action-cavity feedback variable-displacement vane pump, the design and arrangement of the control valve are more feasible, pressure control is more stable, and the two-stage displacement varying can be actively controlled by the switch type electromagnetic valve.
Description
Technical field
The present invention relates to lubricating system of IC engine technical field, particularly the control structure of single-acting chamber feedback variable displacement vane pump for a kind of internal combustion engine lubrication.
Background technique
Along with engine lubrication system oil pump becomes the growing and universal of discharge capacity technology, blade type oil pump is applied widely, existing vane pump comprises single-acting chamber feedback and two kinds of variable formats of double-action chamber feedback, wherein single action variable chamber can be designed to one-level variable displacement pattern, by electrohydraulic proportional control valve, can realize MAP and control, double-action chamber feedback can be designed to two-stage variable discharge capacity pattern.
Summary of the invention
The technical problem to be solved in the present invention is to provide the control system of a kind of solenoid valve control single-acting chamber feedback variable displacement vane pump, allows single-acting chamber feed back the practicable secondary variable displacement of variable displacement vane pump.
For solving the problems of the technologies described above, technological scheme of the present invention is: the control system of a kind of solenoid valve control single-acting chamber feedback variable displacement vane pump, comprise single-acting chamber feedback variable displacement vane pump, pump discharge, main oil gallery, oil sump, safety valve, main control valve and switch type solenoid valve, described single-acting chamber feedback variable displacement vane pump comprises the pump housing, blade, rotor, feedback pressure oil pocket, slide block rotation locating stud, variable slide block and variable spring, the valve pocket of described safety valve is provided with pump discharge oil duct interface, feedback oil duct interface, spring chamber drain tap, the valve sleeving inner wall bottom of described main control valve is provided with a loop boss, on annular boss, be placed with spring, the spool lower end of main control valve is passed and can be moved downward from spring, between described spool and valve pocket top, it is upper end piston cavity, between described spool and valve pocket bottom, be lower end piston cavity, valve pocket is provided with main oil gallery interface, feedback oil duct interface, spring chamber drain tap, gateway, lower piston chamber, in the one-level variable displacement stage, the lower end piston cavity of main control valve is all the time successively by gateway, lower piston chamber, switch type solenoid valve communicates with oil sump, before the engine oil pressure of main oil gallery does not reach the variable engine oil pressure of one-level of setting, feedback pressure oil pocket is successively by the feedback oil duct interface of main control valve, spring chamber drain tap communicates with oil sump, oil pump is in maximum pump discharge working position, when the engine oil pressure of main oil gallery reaches the variable engine oil pressure of one-level of setting, main control valve spool moves to lower end piston cavity under the engine oil pressure effect of main oil gallery, feedback oil duct interface is closed, when the engine oil pressure of main oil gallery continues to increase, main control valve spool continues descending, feedback pressure oil pocket is successively by the feedback oil duct interface of main control valve, spool oil groove, main oil gallery interface communicates with main oil gallery, the engine oil pressure of main oil gallery enters feedback pressure oil pocket and directly acts on variable slide block, the offset of variable slide block and rotor is reduced, thereby reduce output discharge capacity, when switch type solenoid valve is switched to another working state under control signal effect, switch type solenoid valve is by the lower end piston cavity of main control valve and the pathway closure of oil sump, from then on just enter the secondary variable displacement stage, in the secondary variable displacement stage, the lower end piston cavity of main control valve is all the time successively by gateway, lower piston chamber, switch type solenoid valve communicates with main oil gallery, the engine oil pressure of main oil gallery acts on upper end piston cavity and the lower end piston cavity of main control valve simultaneously, main control valve spool is upper, under the differential pressure effect of lower end piston cavity, enter high voltage control state, before the engine oil pressure of main oil gallery does not reach the variable engine oil pressure of secondary of setting, feedback pressure oil pocket is successively by the feedback oil duct interface of main control valve, spring chamber drain tap communicates with oil sump, oil pump is in maximum pump discharge working position, when the engine oil pressure of main oil gallery reaches the variable engine oil pressure of secondary of setting, main control valve spool moves to lower end piston cavity under the engine oil pressure effect of main oil gallery, feedback oil duct interface is closed, when the engine oil pressure of main oil gallery continues to increase, main control valve spool continues descending, feedback pressure oil pocket is successively by the feedback oil duct interface of main control valve, spool oil groove, main oil gallery interface communicates with main oil gallery, the engine oil pressure of main oil gallery enters feedback pressure oil pocket and directly acts on variable slide block, the offset of variable slide block and rotor is reduced, thereby reduce output discharge capacity, when the engine oil pressure of main oil gallery is increased to minimum setting pressure of relief valve, the spool of safety valve continues to move down under the effect of pump discharge engine oil pressure, the engine oil pressure of pump discharge enters feedback pressure oil pocket by safety valve pump discharge oil duct interface, feedback oil duct interface, and oil pump enters security operating mode.
In technique scheme, in the structure of single-acting chamber feedback variable displacement vane pump, by increasing main control valve, realized two-stage variable discharge capacity, utilize the poor differential pressure that forms in cross section between main control valve upper end piston cavity and lower end piston cavity to control, than double-action chamber feedback variable displacement vane pump designs simplification, the design of control valve and layout are more flexible, and pressure is controlled more steady; Simultaneously can ACTIVE CONTROL secondary discharge capacity by switch type solenoid valve variable.
Accompanying drawing explanation
Fig. 1 is structural representation of the present invention.
Embodiment
The control system of a kind of solenoid valve control single-acting chamber feedback variable displacement vane pump as shown in Figure 1, comprise single-acting chamber feedback variable displacement vane pump 1, pump discharge 2, main oil gallery 3, machine oil cooler 4, oil strainer 5, oil sump 6, safety valve 7, main control valve 8 and switch type solenoid valve 9, described single-acting chamber feedback variable displacement vane pump 1 comprises the pump housing 11, blade 15, rotor 16, feedback pressure oil pocket 14, slide block rotation locating stud 12, variable slide block 13 and variable spring 17, the valve pocket of described safety valve 7 is provided with pump discharge oil duct interface 71, feedback oil duct interface 72, spring chamber drain tap 73, the valve sleeving inner wall bottom of described main control valve 8 is provided with a loop boss, on annular boss, be placed with spring, the spool lower end of main control valve 8 is passed and can be moved downward from spring, between described spool and valve pocket top, it is upper end piston cavity 81, between described spool and valve pocket bottom, be lower end piston cavity 82, valve pocket is provided with main oil gallery interface 83, feedback oil duct interface 84, spring chamber drain tap 85, gateway, lower piston chamber 86, in the one-level variable displacement stage, the lower end piston cavity 82 of main control valve 8 is all the time successively by gateway, lower piston chamber 86, switch type solenoid valve 9 communicates with oil sump 6, before the engine oil pressure of main oil gallery 3 does not reach the variable engine oil pressure of one-level of setting, feedback pressure oil pocket 14 is successively by the feedback oil duct interface 84 of main control valve 8, spring chamber drain tap 85 communicates with oil sump 6, oil pump is in maximum pump discharge working position, when the engine oil pressure of main oil gallery 3 reaches the variable engine oil pressure of one-level of setting, the spool of main control valve 8 moves to lower end piston cavity 82 under the engine oil pressure effect of main oil gallery 3, feedback oil duct interface 84 is closed, when the engine oil pressure of main oil gallery 3 continues to increase, the spool of main control valve 8 continues descending, feedback pressure oil pocket 14 is successively by the feedback oil duct interface 84 of main control valve 8, spool oil groove 87, main oil gallery interface 83 communicates with main oil gallery 3, the engine oil pressure of main oil gallery 3 enters feedback pressure oil pocket 14 and directly acts on variable slide block 13, variable slide block 13 and the offset of rotor 16 are reduced, thereby reduce output discharge capacity, when switch type solenoid valve 9 is switched to another working state under control signal effect, switch type solenoid valve 9 is the pathway closure with oil sump 6 by the lower end piston cavity of main control valve 8 82, from then on just enter the secondary variable displacement stage, in the secondary variable displacement stage, the lower end piston cavity 82 of main control valve 8 is all the time successively by gateway, lower piston chamber 86, switch type solenoid valve 9 communicates with main oil gallery 3, the engine oil pressure of main oil gallery 3 acts on upper end piston cavity 81 and the lower end piston cavity 82 of main control valve 8 simultaneously, the spool of main control valve 8 is upper, lower end piston cavity 81, under 82 differential pressure effect, enter high voltage control state, before the engine oil pressure of main oil gallery 3 does not reach the variable engine oil pressure of secondary of setting, feedback pressure oil pocket 14 is successively by the feedback oil duct interface 84 of main control valve 8, spring chamber drain tap 85 communicates with oil sump 6, oil pump is in maximum pump discharge working position, when the engine oil pressure of main oil gallery 3 reaches the variable engine oil pressure of secondary of setting, the spool of main control valve 8 moves to lower end piston cavity 82 under the engine oil pressure effect of main oil gallery 3, feedback oil duct interface 84 is closed, when the engine oil pressure of main oil gallery 3 continues to increase, the spool of main control valve 8 continues descending, feedback pressure oil pocket 14 is successively by the feedback oil duct interface 84 of main control valve 8, spool oil groove 87, main oil gallery interface 83 communicates with main oil gallery 3, the engine oil pressure of main oil gallery 3 enters feedback pressure oil pocket 14 and directly acts on variable slide block 13, variable slide block 13 and the offset of rotor 16 are reduced, thereby reduce output discharge capacity, when the engine oil pressure of main oil gallery 3 is increased to the set pressure of safety valve 7, the spool of safety valve 7 continues to move down under pump discharge 2 engine oil pressure effects, the engine oil pressure of pump discharge 2 enters feedback pressure oil pocket 14 by pump discharge oil duct interface 71, the feedback oil duct interface 72 of safety valve 7, and oil pump enters security operating mode.
Claims (1)
1. the control system of solenoid valve control single-acting chamber feedback variable displacement vane pump, comprise single-acting chamber feedback variable displacement vane pump, pump discharge, main oil gallery, oil sump, described single-acting chamber feedback variable displacement vane pump comprises the pump housing, blade, rotor, feedback pressure oil pocket, slide block rotation locating stud, variable slide block and variable spring, it is characterized in that:
Described combination control structure also comprises safety valve, main control valve and switch type solenoid valve, and the valve pocket of described safety valve is provided with pump discharge oil duct interface, feedback oil duct interface, spring chamber drain tap; The valve sleeving inner wall bottom of described main control valve is provided with a loop boss, on annular boss, be placed with spring, the spool lower end of main control valve is passed and can be moved downward from spring, between described spool and valve pocket top, it is upper end piston cavity, between described spool and valve pocket bottom, be lower end piston cavity, valve pocket is provided with main oil gallery interface, feedback oil duct interface, spring chamber drain tap, gateway, lower piston chamber;
In the one-level variable displacement stage, the lower end piston cavity of main control valve is all the time successively by gateway, lower piston chamber, switch type solenoid valve communicates with oil sump, before the engine oil pressure of main oil gallery does not reach the variable engine oil pressure of one-level of setting, feedback pressure oil pocket is successively by the feedback oil duct interface of main control valve, spring chamber drain tap communicates with oil sump, oil pump is in maximum pump discharge working position, when the engine oil pressure of main oil gallery reaches the variable engine oil pressure of one-level of setting, main control valve spool moves to lower end piston cavity under the engine oil pressure effect of main oil gallery, feedback oil duct interface is closed, when the engine oil pressure of main oil gallery continues to increase, main control valve spool continues descending, feedback pressure oil pocket is successively by the feedback oil duct interface of main control valve, spool oil groove, main oil gallery interface communicates with main oil gallery, the engine oil pressure of main oil gallery enters feedback pressure oil pocket and directly acts on variable slide block, the offset of variable slide block and rotor is reduced, thereby reduce output discharge capacity,
When switch type solenoid valve is switched to another working state under control signal effect, switch type solenoid valve is by the lower end piston cavity of main control valve and the pathway closure of oil sump, from then on just enter the secondary variable displacement stage, in the secondary variable displacement stage, the lower end piston cavity of main control valve is all the time successively by gateway, lower piston chamber, switch type solenoid valve communicates with main oil gallery, the engine oil pressure of main oil gallery acts on upper end piston cavity and the lower end piston cavity of main control valve simultaneously, main control valve spool is upper, under the differential pressure effect of lower end piston cavity, enter high voltage control state, before the engine oil pressure of main oil gallery does not reach the variable engine oil pressure of secondary of setting, feedback pressure oil pocket is successively by the feedback oil duct interface of main control valve, spring chamber drain tap communicates with oil sump, oil pump is in maximum pump discharge working position, when the engine oil pressure of main oil gallery reaches the variable engine oil pressure of secondary of setting, main control valve spool moves to lower end piston cavity under the engine oil pressure effect of main oil gallery, feedback oil duct interface is closed, when the engine oil pressure of main oil gallery continues to increase, main control valve spool continues descending, feedback pressure oil pocket is successively by the feedback oil duct interface of main control valve, spool oil groove, main oil gallery interface communicates with main oil gallery, the engine oil pressure of main oil gallery enters feedback pressure oil pocket and directly acts on variable slide block, the offset of variable slide block and rotor is reduced, thereby reduce output discharge capacity,
When the engine oil pressure of main oil gallery is increased to minimum setting pressure of relief valve, the spool of safety valve continues to move down under the effect of pump discharge engine oil pressure, the engine oil pressure of pump discharge enters feedback pressure oil pocket by safety valve pump discharge oil duct interface, feedback oil duct interface, and oil pump enters security operating mode.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201410248741.1A CN104047665B (en) | 2014-06-06 | 2014-06-06 | A kind of control system of magnetic valve control single-acting chamber feedback variable displacement vane pump |
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| CN201410248741.1A CN104047665B (en) | 2014-06-06 | 2014-06-06 | A kind of control system of magnetic valve control single-acting chamber feedback variable displacement vane pump |
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| CN104047665A true CN104047665A (en) | 2014-09-17 |
| CN104047665B CN104047665B (en) | 2016-08-24 |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105114146A (en) * | 2015-09-28 | 2015-12-02 | 湖南机油泵股份有限公司 | Control system of main oil duct feedback single-cavity two-stage variable-displacement vane pump |
| CN105351188A (en) * | 2015-11-04 | 2016-02-24 | 湖南机油泵股份有限公司 | Combination valve type control system of secondary variable displacement vane pump |
| CN106870059A (en) * | 2015-09-10 | 2017-06-20 | 明和工业株式会社 | Double pump system |
| CN108397256A (en) * | 2018-03-26 | 2018-08-14 | 重庆长安汽车股份有限公司 | The pressure release control system of lubricating oil pump |
| CN108894982A (en) * | 2018-08-21 | 2018-11-27 | 湖南机油泵股份有限公司 | A kind of variable displacement vane pump with sealing compensation function |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1873363A2 (en) * | 2002-04-03 | 2008-01-02 | BorgWarner Inc. | Variable displacement pump and control therefor |
| CN102506287A (en) * | 2011-11-17 | 2012-06-20 | 宁波圣龙汽车动力系统股份有限公司 | Oil pump with variable displacement and control method of oil pump |
| CN102844570A (en) * | 2010-03-05 | 2012-12-26 | 皮尔伯格泵技术有限责任公司 | Variable displacement lubricant pump |
| US20130164163A1 (en) * | 2011-12-21 | 2013-06-27 | Hitachi Automotive Systems, Ltd. | Variable displacement pump |
| DE102013216485A1 (en) * | 2012-09-07 | 2014-03-13 | Hitachi Automotive Systems, Ltd. | Adjustable oil pump |
| DE102013224057A1 (en) * | 2012-11-27 | 2014-05-28 | Hitachi Automotive Systems, Ltd. | Variable displacement oil pump for internal combustion engine in vehicle, has output channel outputting fluid in control hydraulic chamber along direction to vary variation of opening area of introduction channel against opposite direction |
| CN204024754U (en) * | 2014-06-06 | 2014-12-17 | 湖南机油泵股份有限公司 | The control system of a kind of solenoid valve control single-acting chamber feedback variable displacement vane pump |
-
2014
- 2014-06-06 CN CN201410248741.1A patent/CN104047665B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1873363A2 (en) * | 2002-04-03 | 2008-01-02 | BorgWarner Inc. | Variable displacement pump and control therefor |
| CN102844570A (en) * | 2010-03-05 | 2012-12-26 | 皮尔伯格泵技术有限责任公司 | Variable displacement lubricant pump |
| CN102506287A (en) * | 2011-11-17 | 2012-06-20 | 宁波圣龙汽车动力系统股份有限公司 | Oil pump with variable displacement and control method of oil pump |
| US20130164163A1 (en) * | 2011-12-21 | 2013-06-27 | Hitachi Automotive Systems, Ltd. | Variable displacement pump |
| DE102013216485A1 (en) * | 2012-09-07 | 2014-03-13 | Hitachi Automotive Systems, Ltd. | Adjustable oil pump |
| DE102013224057A1 (en) * | 2012-11-27 | 2014-05-28 | Hitachi Automotive Systems, Ltd. | Variable displacement oil pump for internal combustion engine in vehicle, has output channel outputting fluid in control hydraulic chamber along direction to vary variation of opening area of introduction channel against opposite direction |
| CN204024754U (en) * | 2014-06-06 | 2014-12-17 | 湖南机油泵股份有限公司 | The control system of a kind of solenoid valve control single-acting chamber feedback variable displacement vane pump |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106870059A (en) * | 2015-09-10 | 2017-06-20 | 明和工业株式会社 | Double pump system |
| CN106870059B (en) * | 2015-09-10 | 2019-04-16 | 明和工业株式会社 | Double pump system |
| CN105114146A (en) * | 2015-09-28 | 2015-12-02 | 湖南机油泵股份有限公司 | Control system of main oil duct feedback single-cavity two-stage variable-displacement vane pump |
| CN105351188A (en) * | 2015-11-04 | 2016-02-24 | 湖南机油泵股份有限公司 | Combination valve type control system of secondary variable displacement vane pump |
| CN108397256A (en) * | 2018-03-26 | 2018-08-14 | 重庆长安汽车股份有限公司 | The pressure release control system of lubricating oil pump |
| CN108894982A (en) * | 2018-08-21 | 2018-11-27 | 湖南机油泵股份有限公司 | A kind of variable displacement vane pump with sealing compensation function |
| CN108894982B (en) * | 2018-08-21 | 2023-12-05 | 湖南机油泵股份有限公司 | Variable displacement vane pump with seal compensation function |
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| CN104047665B (en) | 2016-08-24 |
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| PE01 | Entry into force of the registration of the contract for pledge of patent right | ||
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Denomination of invention: A control system of solenoid valve controlled single acting cavity feedback variable displacement vane pump Effective date of registration: 20211224 Granted publication date: 20160824 Pledgee: Bank of Beijing Limited by Share Ltd. Changsha branch Pledgor: Hunan Oil Pump Co.,Ltd. Registration number: Y2021430000097 |
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Date of cancellation: 20230105 Granted publication date: 20160824 Pledgee: Bank of Beijing Limited by Share Ltd. Changsha branch Pledgor: Hunan Oil Pump Co.,Ltd. Registration number: Y2021430000097 |
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| PE01 | Entry into force of the registration of the contract for pledge of patent right |
Denomination of invention: A control system of variable displacement vane pump with single-acting cavity feedback controlled by solenoid valve Effective date of registration: 20230130 Granted publication date: 20160824 Pledgee: Bank of Beijing Limited by Share Ltd. Changsha branch Pledgor: Hunan Oil Pump Co.,Ltd. Registration number: Y2023430000008 |