CN109854557A - A kind of double pump with energy-saving pressure preload unit directly drives electric hydrostatic actuator - Google Patents
A kind of double pump with energy-saving pressure preload unit directly drives electric hydrostatic actuator Download PDFInfo
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- CN109854557A CN109854557A CN201910217348.9A CN201910217348A CN109854557A CN 109854557 A CN109854557 A CN 109854557A CN 201910217348 A CN201910217348 A CN 201910217348A CN 109854557 A CN109854557 A CN 109854557A
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- valve
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Abstract
The invention discloses a kind of double pumps with energy-saving pressure preload unit directly to drive electric hydrostatic actuator, it is provided with pressure preload unit, the pressure for providing low-pressure side for the straight Driving force system of the double pump pre-tightens, pass through the pressure preload unit, no matter hydraulic cylinder is stretched out or retracted (motor rotates forward or reversion), it can realize that the pressure of low pressure oil side pre-tightens；It is pre-tightened by the pressure of a small amount of flow, substantially increases the dynamic property of system；Meanwhile can control clutch disconnection when hydraulic accumulator pressure is higher, it allows third hydraulic pump to stop working to realize energy conservation, clutch engagement is controlled when energy storage pressure deficiency, be hydraulic accumulator filling liquid；Both response time needed for the manufacturing, the performance requirements such as speed are able to satisfy, and are able to achieve the accurate control of actuator position, while increasing substantially system energy efficiency compared with valve control system, high reliablity, maintenance are small and energy saving.
Description
Technical field
The present invention relates to electric hydrostatics to act device technical field, and in particular to a kind of double pump with energy-saving pressure preload unit
It is straight to drive electric hydrostatic actuator.
Background technique
The straight electricity hydrostatic actuator system that drives is that hydraulic pump is driven to realize the control of position, speed etc. by servo motor.
Its working principle is that controller issues control signal according to control instruction and sensor feedback, the revolving speed of motor is controlled, thus band
Dynamic constant displacement pump controls output displacement, the speed of hydraulic cylinder to change revolving speed, direction of rotation, or the output flow by changing pump
Degree, acceleration and power etc..
Currently, the hydraulic system of three categories maturation: common control system is primarily present by control form classification, ratio control
System, servo-control system.Ratio control system and servo-control system are that a kind of stability is good, and dynamic response is fast, accuracy
High automatic liquid pressure control system is mainly used in all kinds of medium-to-high grade hydraulic machineries and device, but its efficiency is lower, cost
Height, and it is difficult in maintenance, use environment is required stringent.In production, the hydraulic system of many production equipments is less being pursued
The performances such as its response time, speed, but need to carry out the running position of hydraulic system the automation control of closed loop；And common
Hydraulic control system is difficult to meet such control characteristic requirement again, and existing hydraulic control system can not be taken into account well
The hydraulic system characteristic requirements of such production equipment.
Summary of the invention
Make to solve the above problems, directly driving electric hydrostatic the present invention provides a kind of double pump with energy-saving pressure preload unit
Dynamic device, is not only able to satisfy the performance requirements such as response time, speed needed for the manufacturing, but also be able to achieve the accurate of actuator position
Control.
Technical proposal that the invention solves the above-mentioned problems is: it is quiet that a kind of double pump with energy-saving pressure preload unit directly drives electricity
Liquid actuator, including it is hydraulic actuator, the first solenoid directional control valve, the second solenoid directional control valve, the first hydraulic pump, second hydraulic
Pump, the first check valve, second one-way valve, displacement sensor, motor, motor driver, power supply, controller, hydraulic accumulator with
And pressure preload unit, the oil inlet of first check valve are connected with the oil inlet of the second one-way valve, described first is single
It is connected to the oil outlet of valve on the pipeline that first hydraulic pump is connect with first solenoid directional control valve, described second is unidirectional
The oil outlet of valve is connected on the pipeline that second hydraulic pump is connect with second solenoid directional control valve；The pressure pre-tightens single
Member includes a rectification valve group, third hydraulic pump, hydraulic accumulator, pressure sensor and overflow valve；The third hydraulic pump
Two hydraulic fluid ports are connect with the rectification valve group；The oil inlet of the rectification valve group is also respectively connected in the hydraulic accumulator, overflows
On the pipeline that stream valve and first hydraulic pump are connect with the second hydraulic pump；The oil outlet of the rectification valve group is also respectively connected with
In on the pipeline that the hydraulic accumulator, overflow valve and first check valve are connect with the second one-way valve；The pressure
Force snesor is connected on the pipeline that the rectification valve group is connect with the hydraulic accumulator；It is additionally provided on the motor to control
Make the clutch of the third hydraulic pump；The clutch, the first solenoid directional control valve, the second solenoid directional control valve, displacement sensor,
Pressure sensor, motor driver, overflow valve are electrically connected the controller.
Preferably, the rectification valve group include sequentially connected third check valve, the 4th check valve, the 5th check valve and
6th check valve, one hydraulic fluid port of the third hydraulic pump are connected to the oil inlet of the third check valve and going out for the 4th check valve
On the pipeline of hydraulic fluid port connection, the oil outlet of oil inlet and the 6th check valve that another hydraulic fluid port is connected to the 5th check valve connects
On the pipeline connect.
Preferably, a hydraulic fluid port of the overflow valve is connected to the oil inlet and the 6th check valve of the 4th check valve
On the pipeline of oil inlet connection, another hydraulic fluid port is connected to the oil outlet of the third check valve and the oil outlet of the 5th check valve
On the pipeline of connection.
Preferably, the solenoid valve is two-position two-way solenoid valve.
Preferably, the motor driver is servo-driver or frequency converter.
Beneficial effects of the present invention: a kind of double pump with energy-saving pressure preload unit directly drives electric hydrostatic actuator setting
There is pressure preload unit, the pressure for providing low-pressure side for the straight Driving force system of the double pump pre-tightens, by the pressure preload unit, no
It stretches out or retracts (motor is rotated forward or inverted) by hydraulic cylinder, can realize that the pressure of low pressure oil side pre-tightens；By flowing on a small quantity
The pressure of amount pre-tightens, and substantially increases the dynamic property of system；Meanwhile it can control clutch when hydraulic accumulator pressure is higher
Device disconnects, and third hydraulic pump is allowed to stop working to realize energy conservation, and clutch engagement is controlled when energy storage pressure deficiency, is hydraulic
Accumulator filling liquid；Not only the performance requirements such as response time, speed needed for the manufacturing are able to satisfy, but also are able to achieve actuator position
Accurate control, while increasing substantially system energy efficiency compared with valve control system, high reliablity, maintenance are small and energy saving.
Detailed description of the invention
Fig. 1 is the structural representation that a kind of double pump with energy-saving pressure preload unit of the present invention directly drives electric hydrostatic actuator
Figure.
In figure: 1- displacement sensor；2- hydraulic accumulator；3- pressure sensor；The first solenoid directional control valve of 4-；5- second
Solenoid directional control valve；The first check valve of 6-；7- second one-way valve；8- overflow valve；9- third check valve；The 5th check valve of 10-；11-
4th check valve；The 6th check valve of 12-；13- third hydraulic pump；The first hydraulic pump of 14-；15- motor；The second hydraulic pump of 16-；
17- motor driver；18- controller；19- power supply；20- clutch；21- hydraulic actuator.
Specific embodiment
In order to illustrate the embodiments of the present invention more clearly with technical solution in the prior art, Detailed description of the invention will be compareed below
A specific embodiment of the invention.It should be evident that drawings in the following description are only some embodiments of the invention, for
For those of ordinary skill in the art, without creative efforts, it can also be obtained according to these attached drawings other
Attached drawing, and obtain other embodiments, the present invention is not restricted to the embodiment.
Please refer to Fig. 1.A kind of double pump with energy-saving pressure preload unit of the embodiment of the present invention directly drives electric hydrostatic actuation
Device, including hydraulic actuator 21, the first solenoid directional control valve 4, the second solenoid directional control valve 5, the first hydraulic pump 14, the second hydraulic pump
16, the first check valve 6, second one-way valve 7, displacement sensor 1, motor 15, motor driver 17, power supply 19, controller 18, liquid
Press accumulator 2 and pressure preload unit, the oil inlet string of the oil inlet of first check valve 6 and the second one-way valve 7
Connection, the oil outlet of first check valve 6 are connected to the pipe that first hydraulic pump 14 is connect with first solenoid directional control valve 4
On the road, the oil outlet of the second one-way valve 7 is connected to what second hydraulic pump 16 was connect with second solenoid directional control valve 5
On pipeline；The pressure preload unit include one rectification valve group, third hydraulic pump 13, hydraulic accumulator 2, pressure sensor 3 with
And overflow valve 8；Two hydraulic fluid ports of the third hydraulic pump 13 are connect with the rectification valve group；The oil inlet of the rectification valve group is also
It is connected to the pipeline that the hydraulic accumulator 2, overflow valve 8 and first hydraulic pump 14 are connect with the second hydraulic pump 16
On；The oil outlet of the rectification valve group is also respectively connected in the hydraulic accumulator 2, overflow valve 8 and first check valve 6
On the pipeline being connect with the second one-way valve 7；The pressure sensor 3 is connected to the rectification valve group and the hydraulic energy-accumulating
On the pipeline that device 2 connects；The clutch 20 to control the third hydraulic pump 13 is additionally provided on the motor 15；The clutch
Device 20, the second solenoid directional control valve 5, displacement sensor 1, pressure sensor 3, motor driver 17, overflows at first solenoid directional control valve 4
Stream valve 8 is electrically connected the controller 18.
Supplementary explanation, the hydraulic actuator 21 can be hydraulic cylinder, at work, open the first electromagnetism by controller
Reversal valve 4, the second solenoid directional control valve 5 control the first hydraulic pump 14 and the second hydraulic pump 16 by controlling the revolving speed of motor 15
Flow, and then the flow for controlling two chamber of hydraulic cylinder realizes the control of its displacement, speed, acceleration etc., passes through displacement sensor 1
It compares with the input of controller 18 instruction, outputs signal to motor driver 17, realize closed-loop control to control motor speed.
Referring to Fig. 1.Rectification valve group described in this example, a kind of embodiment can be include sequentially connected
Three check valves 9, the 4th check valve 11, the 5th check valve 10 and the 6th check valve 12,13 1 hydraulic fluid ports of the third hydraulic pump
It is connected on the pipeline that the oil inlet of the third check valve 9 is connect with the oil outlet of the 4th check valve 11, another hydraulic fluid port connects
It is connected on the pipeline of the oil outlet connection of the oil inlet, the 6th check valve 12 of the 5th check valve 10, the purpose for the arrangement is that:
Third hydraulic pump 13 is arrived after the rectified valve group of oil liquid in hydraulic accumulator 2, and it is whole to be sent to this after being pressurized by third hydraulic pump 13
Valve group is flowed, finally arrives the tie point between hydraulic accumulator 2 and the first check valve 6 and second one-way valve 7, and then be sent to first
Pipeline between hydraulic pump 14 and the first solenoid directional control valve 4 is sent between the second hydraulic pump 16 and the second solenoid directional control valve 5
Pipeline, improve the minimum pressure of low-pressure side.
Referring to Fig. 1.In this example, a hydraulic fluid port of the overflow valve 8 be can connect in the 4th check valve 11
The pipeline that is connect with the oil inlet of the 6th check valve 12 of oil inlet on, another hydraulic fluid port is connected to the third check valve 9
On the pipeline that oil outlet is connect with the oil outlet of the 5th check valve 10, the purpose for the arrangement is that: the overflow valve 8 of setting can play
The effects of level pressure overflow, pressure stabilizing, system unloaded and safeguard protection, dynamically adjusts the minimum pressure of the pressure preload unit, to mention
The dynamic property of high system.
In this example, first solenoid directional control valve 4, the second solenoid directional control valve 5 can be two-position two-way solenoid valve, do so
Benefit be: the first solenoid directional control valve 4 of setting, the second solenoid directional control valve 5 to cooperate the positive and negative rotation of motor 15 to commutate,
Realize hydraulic actuator 21(hydraulic cylinder) stretching or retraction movement.It is, of course, also possible to there is other modes identical to realize
Function and effect.
In this example, the motor driver 17 can be servo-driver or frequency converter, the purpose for the arrangement is that: setting
Motor driver 17 can be to control revolving speed and the positive and negative rotation of motor 15, when motor 15 is servo motor, motor driver
17 correspond to servo-driver；When motor 15 is variable-frequency motor, motor driver 17 corresponds to frequency converter.
Supplementary explanation, the system are made of three constant displacement pumps, when piston stretches out, instead of in the hydraulic accumulator 2 of fuel tank
Oil liquid by the second hydraulic pump 16 be pressurized, through the second solenoid directional control valve 5 arrive the big chamber of hydraulic actuator 21.Small chamber oil liquid is through
It is discharged after one solenoid directional control valve 4 by the first hydraulic pump 14, finally flows back to hydraulic accumulator 2.Meanwhile the oil in hydraulic accumulator 2
To third hydraulic pump 13 after the rectification valve group that liquid is constituted via check valve 9~12, and this is sent to after being pressurized by third hydraulic pump 13
Rectification valve group finally arrives the tie point between hydraulic accumulator 2 and the first check valve 6 and second one-way valve 7, and then is sent to the
Pipeline between one hydraulic pump 14 and the first solenoid directional control valve 4 or be sent to the second hydraulic pump 16 and the second solenoid directional control valve 5 it
Between pipeline, improve the minimum pressure of low-pressure side.And this is adjusted come dynamic by the detection of pressure sensor 3 and proportional pressure control valve 8
The minimum pressure of pressure preload unit, to improve the dynamic property of system.Simultaneously disconnected when 2 pressure of hydraulic accumulator is higher from
Clutch 20 is to realize energy conservation, and when 2 insufficient pressure of hydraulic accumulator, clutch 20 is engaged, and the starting of third hydraulic pump 13 is hydraulic storage
It can 2 filling liquid of device.Piston retracts process, substantially similar to the above process.
Specific embodiments of the present invention are described in detail above.It should be appreciated that those skilled in the art are without wound
The property made labour, which according to the present invention can conceive, makes many modifications and variations.Therefore, all those skilled in the art
Present inventive concept passes through the available technical solution of logical analysis, reasoning, or a limited experiment in the prior art, all
It should be in protection scope determined by the claims.
Claims (5)
1. a kind of double pump with energy-saving pressure preload unit directly drives electric hydrostatic actuator, it is characterised in that: including hydraulic execution
Element (21), the first solenoid directional control valve (4), the second solenoid directional control valve (5), the first hydraulic pump (14), the second hydraulic pump (16),
One check valve (6), second one-way valve (7), displacement sensor (1), motor (15), motor driver (17), power supply (19), control
Device (18), hydraulic accumulator (2) and pressure preload unit, the oil inlet of first check valve (6) are unidirectional with described second
The oil inlet of valve (7) is connected, and the oil outlet of first check valve (6) is connected to first hydraulic pump (14) and described first
Solenoid directional control valve (4) connection pipeline on, the oil outlet of the second one-way valve (7) be connected to second hydraulic pump (16) with
On the pipeline of second solenoid directional control valve (5) connection；The pressure preload unit includes rectification a valve group, third hydraulic pump
(13), hydraulic accumulator (2), pressure sensor (3) and overflow valve (8)；Two hydraulic fluid ports of the third hydraulic pump (13) with
The rectification valve group connection；The oil inlet of the rectification valve group is also respectively connected in the hydraulic accumulator (2), overflow valve (8)
And on the pipeline that is connect with the second hydraulic pump (16) of first hydraulic pump (14)；The oil outlet of the rectification valve group is also distinguished
The hydraulic accumulator (2), overflow valve (8) and first check valve (6) is connected to connect with the second one-way valve (7)
Pipeline on；The pressure sensor (3) is connected on the pipeline that the rectification valve group is connect with the hydraulic accumulator (2)；
The clutch (20) to control the third hydraulic pump (13) is additionally provided on the motor (15)；The clutch (20),
One solenoid directional control valve (4), the second solenoid directional control valve (5), displacement sensor (1), pressure sensor (3), motor driver (17),
Overflow valve (8) is electrically connected the controller (18).
2. a kind of double pump with energy-saving pressure preload unit according to claim 1 directly drives electric hydrostatic actuator, special
Sign is: the rectification valve group includes sequentially connected third check valve (9), the 4th check valve (11), the 5th check valve (10)
And the 6th check valve (12), (13) hydraulic fluid ports of the third hydraulic pump are connected to the oil inlet of the third check valve (9)
On the pipeline connecting with the oil outlet of the 4th check valve (11), another hydraulic fluid port is connected to the oil inlet of the 5th check valve (10)
On the pipeline that mouth is connect with the oil outlet of the 6th check valve (12).
3. a kind of double pump with energy-saving pressure preload unit according to claim 2 directly drives electric hydrostatic actuator, special
Sign is: a hydraulic fluid port of the overflow valve (8) is connected to the oil inlet and the 6th check valve of the 4th check valve (11)
(12) on the pipeline of oil inlet connection, another hydraulic fluid port is connected to the oil outlet and the 5th of the third check valve (9) unidirectionally
On the pipeline of the oil outlet connection of valve (10).
4. a kind of double pump with energy-saving pressure preload unit according to claim 1 directly drives electric hydrostatic actuator, special
Sign is: first solenoid directional control valve 4, the second solenoid directional control valve 5 are two-position two-way solenoid valve.
5. a kind of double pump with energy-saving pressure preload unit according to claim 1 directly drives electric hydrostatic actuator, special
Sign is: the motor driver (17) is servo-driver or frequency converter.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910217348.9A CN109854557B (en) | 2019-03-21 | 2019-03-21 | Double-pump direct-drive electro-hydrostatic actuator with energy-saving pressure pre-tightening unit |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910217348.9A CN109854557B (en) | 2019-03-21 | 2019-03-21 | Double-pump direct-drive electro-hydrostatic actuator with energy-saving pressure pre-tightening unit |
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| CN109854557A true CN109854557A (en) | 2019-06-07 |
| CN109854557B CN109854557B (en) | 2020-03-27 |
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| CN201910217348.9A Active CN109854557B (en) | 2019-03-21 | 2019-03-21 | Double-pump direct-drive electro-hydrostatic actuator with energy-saving pressure pre-tightening unit |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110886728A (en) * | 2019-11-07 | 2020-03-17 | 南京航空航天大学 | Intelligent material driven double-pump integrated electro-hydrostatic actuator and working method thereof |
| CN111219369A (en) * | 2020-01-23 | 2020-06-02 | 福建工程学院 | Closed hydraulic circuit double-hydraulic-cylinder actuator system |
| CN112160948A (en) * | 2020-09-09 | 2021-01-01 | 南京晨光集团有限责任公司 | Linear hydraulic driving system based on quick response of intelligent pump |
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| CN109026864A (en) * | 2018-09-20 | 2018-12-18 | 中冶焦耐(大连)工程技术有限公司 | Hydraulic device is used in a kind of control of novel catch wheel |
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| US20110030364A1 (en) * | 2008-02-12 | 2011-02-10 | Parker-Hannifin Corporation | Flow management system for hydraulic work machine |
| CN104314924A (en) * | 2014-08-27 | 2015-01-28 | 南京创贝高速传动机械有限公司 | Hydraulic cylinder testing bed system |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110886728A (en) * | 2019-11-07 | 2020-03-17 | 南京航空航天大学 | Intelligent material driven double-pump integrated electro-hydrostatic actuator and working method thereof |
| CN111219369A (en) * | 2020-01-23 | 2020-06-02 | 福建工程学院 | Closed hydraulic circuit double-hydraulic-cylinder actuator system |
| CN112160948A (en) * | 2020-09-09 | 2021-01-01 | 南京晨光集团有限责任公司 | Linear hydraulic driving system based on quick response of intelligent pump |
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| CN109854557B (en) | 2020-03-27 |
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