CN109915427A - A kind of three pumps with back pressure control are straight to drive electric hydrostatic actuator - Google Patents
A kind of three pumps with back pressure control are straight to drive electric hydrostatic actuator Download PDFInfo
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- CN109915427A CN109915427A CN201910217349.3A CN201910217349A CN109915427A CN 109915427 A CN109915427 A CN 109915427A CN 201910217349 A CN201910217349 A CN 201910217349A CN 109915427 A CN109915427 A CN 109915427A
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Abstract
The electric hydrostatic actuator of the straight drive of three pumps with back pressure control that the invention discloses a kind of, is related to Actuator technique field.Including hydraulic actuator, the first constant displacement pump, the second constant displacement pump, third constant displacement pump, and the control motor operated to control first constant displacement pump, the second constant displacement pump, third constant displacement pump；It further include the hydraulic accumulator being connected to simultaneously with the second hydraulic fluid port of the first constant displacement pump, the second constant displacement pump, third constant displacement pump；It further include to the frequency converter being connect with the control motor and the external power supply being connect with frequency converter；And it is connect with first solenoid valve and second solenoid valve, and be connected to the central controller of the control motor.The flow of the pump housing is controlled by controlling the revolving speed of motor, and then hydraulic cylinder back pressure is controlled to realize the control of its displacement, speed etc., the information such as the pressure detected by central controller according to sensor control driver or frequency converter, it realizes motor speed closed-loop control, increases substantially dynamic performance.
Description
Technical field
The present invention relates to Actuator technique field more particularly to a kind of electric hydrostatic actuations of the straight drive of three pumps with back pressure control
Device.
Background technique
Currently, hydraulic system is primarily present three categories by control form classification: common control system, 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, and accuracy is 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, and cost is high,
And it is difficult in maintenance, use environment is required stringent.In production, the hydraulic system of many production equipments is less pursuing its sound
Between seasonable, the performances such as speed, but need to carry out the running position of hydraulic system the automation control of closed loop；And commonly hydraulic
Control system is difficult to meet its such control characteristic requirement again, and existing hydraulic control system can not take into account this well
The hydraulic system characteristic requirements of class production equipment.
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 the output of hydraulic actuator to change revolving speed, direction of rotation, or the output flow by changing pump
Displacement, speed, acceleration and power etc., but the shortcomings that there are bad dynamic performances.
Summary of the invention
The straight drive electricity hydrostatic actuator with back pressure control that the present invention provides a kind of, according to the control principle of servo-system,
The flow of pump is controlled by control motor speed, and then realization is to the displacement of hydraulic actuator, the control of speed, acceleration
System, to solve the above problems.
Technical proposal that the invention solves the above-mentioned problems is: providing a kind of electric hydrostatic actuation of the straight drive of three pumps with back pressure control
Device, including hydraulic actuator, the first constant displacement pump, the second constant displacement pump, third constant displacement pump, and it is quantitative to control described first
The control motor that pump, the second constant displacement pump, third constant displacement pump operate；First constant displacement pump, the second constant displacement pump, on third constant displacement pump
The first hydraulic fluid port and the second hydraulic fluid port are offered, the first hydraulic pipeline and the second hydraulic tube are connected on the hydraulic actuator
Road, wherein the first hydraulic pipeline is equipped with two first points be connected to respectively with the first hydraulic fluid port of the first constant displacement pump and the second constant displacement pump
Branch hydraulic pipeline and the second branch hydraulic pipeline, second hydraulic pipeline are then connected to the first hydraulic fluid port of the third constant displacement pump,
And the first solenoid valve is equipped on the first hydraulic pipeline, second hydraulic hydraulic pipeline is equipped with second solenoid valve；Further include
The hydraulic accumulator being connected to simultaneously with the second hydraulic fluid port of the first constant displacement pump, the second constant displacement pump, third constant displacement pump；Further include to
The frequency converter of the control motor connection and the external power supply being connect with frequency converter；And it is electric with first solenoid valve and second
Magnet valve electrical connection, and it is connected to the central controller of the control motor.
It preferably, further include make hydraulic oil from the hydraulic accumulator one-way flow to first hydraulic pipeline first
Safety valve, and make hydraulic oil from the hydraulic accumulator one-way flow to the second safety valve of second hydraulic pipeline.
Preferably, being additionally provided on the first branch hydraulic pipeline that the first hydraulic fluid port end with first constant displacement pump is connect makes
Hydraulic oil flows to the first check valve of hydraulic actuator from the first constant displacement pump.
Preferably, further include the first hydraulic fluid port to be connected to the first constant displacement pump and the second hydraulic fluid port end and controlled with the center
The first pressure regulator valve that device processed is electrically connected and is controlled, first pressure regulator valve are bi-bit bi-pass proportioning valve.
Preferably, the first hydraulic fluid port of the first constant displacement pump and the second hydraulic fluid port both ends also set up one with first pressure regulator valve simultaneously
The pressure stabilizing check valve of connection, the oil outlet of the pressure stabilizing check valve are connected to the second hydraulic fluid port end of first constant displacement pump.
Preferably, further include be connected to the second constant displacement pump the first hydraulic fluid port and the second hydraulic fluid port end and with the central controller
The second pressure regulator valve for being electrically connected and being controlled, second pressure regulator valve are bi-bit bi-pass proportioning valve.
Preferably, it is also communicated in the first hydraulic fluid port of the third constant displacement pump and the second hydraulic fluid port both ends and is controlled with the center
The third pressure regulator valve that device is electrically connected and is controlled, the third pressure regulator valve are bi-bit bi-pass proportioning valve.
It preferably, further include the displacement sensing for being arranged on the hydraulic actuator and being connect with the central controller
Device, and the first pressure sensor connecting at first hydraulic pipeline and with the central controller is set and is arranged and is existed
The second pressure sensor connecting at second hydraulic pipeline and with the central controller.
Beneficial effects of the present invention: the present invention drives the running of three constant displacement pumps using control motor simultaneously, due to each
The discharge capacity of constant displacement pump is not identical, to achieve the purpose that control back pressure in hydraulic actuator.Also, in corresponding hydraulic oil
Valve is set at pipeline, is additionally provided with the sensor of multiple detection back pressures, displacement, and is connect with central controller, is controlled by center
Device processed come according to the detection information of the unlatching of valve and sensor come the revolving speed of real-time control servo motor.Moreover, also setting up
There are while having the hydraulic accumulator of fuel tank function and the first safety valve of the air cavity in purging line and the second safety valve.
In addition, pressure regulator valve is also communicated at corresponding constant displacement pump, at first safety valve, the second safety valve and corresponding constant displacement pump
Pressure regulator valve connect with central controller, so as to the accurate regulation of entire actuator.
Detailed description of the invention
Fig. 1 is a kind of straight system structure for driving electric hydrostatic actuator of three pumps with back pressure control of the specific embodiment of the invention
Schematic illustration.
1- hydraulic actuator, the first constant displacement pump of 21-, the second constant displacement pump of 22-, 23- third constant displacement pump, 3- control motor,
31- frequency converter, 32- external power supply, the first solenoid valve of 41-, 42- second solenoid valve, 5- hydraulic accumulator, the first safety valve of 51-,
The second safety valve of 52-, 6- central controller, the first check valve of 71-, 72- pressure stabilizing check valve, the first pressure regulator valve of 81-, 82- second
Pressure regulator valve, 83- third pressure regulator valve, 91- displacement sensor, 92- first pressure sensor, 93- second pressure sensor.
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.
Referring to Fig. 1, a kind of electric hydrostatic actuator of the straight drive of three pumps with back pressure control of the specific embodiment of the invention, including
Hydraulic actuator 1, the first constant displacement pump 21, the second constant displacement pump 22, third constant displacement pump 23, and it is quantitative to control described first
Pump the 21, second constant displacement pump 22, the control motor 3 that third constant displacement pump 23 operates；Hydraulic actuator 1 is specific in the embodiment of the present invention
For horizontal bar hydraulic cylinder, or dual-rod hydraulic cylinder or hydraulic motor etc., control motor 3 can also using variable-frequency motor or
Servo motor, therefore corresponding frequency converter 31 can also be changed to driver according to actual service condition, to be suitable for not
Same accuracy requirement.First constant displacement pump 21, the second constant displacement pump 22 offer the first hydraulic fluid port and on third constant displacement pump 23
Two hydraulic fluid ports, the first hydraulic pipeline and the second hydraulic pipeline are connected on the hydraulic actuator 1, and the connection of the first hydraulic pipeline is single
The rodless cavity of bar hydraulic cylinder, the second hydraulic pipeline are connected to the rod chamber of single-rod cylinder.Wherein the first hydraulic pipeline is equipped with two
The the first branch hydraulic pipeline and second branch's liquid being connected to respectively with the first hydraulic fluid port of the first constant displacement pump 21 and the second constant displacement pump 22
Pressure pipeline, second hydraulic pipeline are then connected to the first hydraulic fluid port of the third constant displacement pump 23, and on the first hydraulic pipeline
Equipped with the first solenoid valve 41, second hydraulic hydraulic pipeline is equipped with second solenoid valve 42；Further include simultaneously with the first constant displacement pump
21, the hydraulic accumulator 5 of the second hydraulic fluid port connection of the second constant displacement pump 22, third constant displacement pump 23；Further include to the control
The frequency converter 31 that motor 3 connects and the external power supply 32 being connect with frequency converter 31；And with first solenoid valve 41 and second
Solenoid valve 42 is electrically connected and is connected to the central controller 6 of the control motor 3.At work, pass through the first solenoid valve of switch
41 and second solenoid valve 42 to indirectly control open central controller 6, it is fixed to control first by the revolving speed of control control motor 3
The flow of the 21, second constant displacement pump 22 of amount pump, third constant displacement pump 23, the control of the position Lai Shixian, speed.
It further include the first safety valve for making hydraulic oil from 5 one-way flow of hydraulic accumulator to first hydraulic pipeline
51, and make second safety valve 52 of the hydraulic oil from 5 one-way flow of hydraulic accumulator to second hydraulic pipeline, it is hydraulic
The oil liquid of accumulator 5 carries out preliminary preload to two sides oil circuit via single first safety valve 51, the second safety valve 52 to avoid gas
The generation in cave.
Be additionally provided on the first branch hydraulic pipeline that the first hydraulic fluid port end with first constant displacement pump 21 is connect make it is hydraulic
Oil flows to the first check valve 71 of hydraulic actuator 1 from the first constant displacement pump 21, to maintain at first constant displacement pump 21
Pressure is stablized.
Further include the first hydraulic fluid port to be connected to the first constant displacement pump 21 and the second hydraulic fluid port end and with the central controller 6
The first pressure regulator valve 81 for being electrically connected and being controlled, first pressure regulator valve 81 are bi-bit bi-pass proportioning valve.In the first constant displacement pump 21
The first hydraulic fluid port and the second hydraulic fluid port both ends also set up a pressure stabilizing check valve 72 in parallel with first pressure regulator valve 81, the pressure stabilizing
The oil outlet of check valve 72 is connected to the second hydraulic fluid port end of first constant displacement pump 21.It further include be connected to the second constant displacement pump 22 the
One hydraulic fluid port and the second hydraulic fluid port end and the second pressure regulator valve 82 for being electrically connected and being controlled with the central controller 6, described second
Pressure regulator valve 82 is bi-bit bi-pass proportioning valve.The first hydraulic fluid port of the third constant displacement pump 23 and the second hydraulic fluid port both ends be also communicated with
The third pressure regulator valve 83 that the central controller 6 is electrically connected and is controlled, the third pressure regulator valve 83 are bi-bit bi-pass proportioning valve.
When hydraulic cylinder piston stretches out, pass through the first constant displacement pump 21, the second constant displacement pump 22 instead of the oil liquid in the hydraulic accumulator 5 of fuel tank
Pressurization arrives hydraulic cylinder rodless cavity through the first solenoid valve 41, and rod chamber oil liquid is after second solenoid valve 42 by 23 row of third constant displacement pump
Out, while the second pressure regulator valve 82 is closed, and according to the opening of the first pressure regulator valve 81 of back pressure demand dynamic adjustment, third pressure regulator valve 83
Size.Can by the adjustment oil inlet quantity of 81 active of the first pressure regulator valve, or pass through third pressure regulator valve active accommodation rod chamber return
Oil mass, to control dynamic backpressure size.
It further include the displacement sensor 91 for being arranged on the hydraulic actuator 1 and being connect with the central controller 6,
And it is arranged at first hydraulic pipeline and the first pressure sensor 92 that connect with the central controller 6 and setting exist
The second pressure sensor 93 being connect at second hydraulic pipeline and with the central controller 6.
By giving 6 input reference signal of central controller, according to the feedback of displacement sensor 91, central controller 6
The revolving speed of control motor 3 and the state of each valve are controlled by calculating output signal.
When the piston of hydraulic cylinder retracts, third quantifies pump output flow to hydraulic cylinder rod chamber, and piston is pushed to retract, this
When by 21 off-load of the first constant displacement pump, therefore the second constant displacement pump 22 is using the constant displacement pump of small displacement, if only passing through the second constant displacement pump 22
Oil extraction, return flow are less than speed caused by 23 flow control hydraulic cylinder of third constant displacement pump, then make hydraulic cylinder rodless cavity pressure
It increases, that is, generates raised back pressure.By first pressure sensor 92 and the detection information of second pressure sensor 93 come dynamic
The magnitude of back pressure is adjusted, to improve the dynamic property of system.
The system sacrifices some efficiencies, but can increase substantially the dynamic property of system.Compared with valve control system, no
Only efficiency amplitude significantly improves, and dynamic property is substantially suitable.
It does not refer to place above, is suitable for the prior art.
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 (8)
1. a kind of three pumps with back pressure control are straight to drive electric hydrostatic actuator, it is characterised in that: including hydraulic actuator (1), the
A certain amount of pump (21), the second constant displacement pump (22), third constant displacement pump (23), and to control first constant displacement pump (21),
The control motor (3) that two constant displacement pumps (22), third constant displacement pump (23) operate；First constant displacement pump (21), the second constant displacement pump
(22), the first hydraulic fluid port and the second hydraulic fluid port are offered on third constant displacement pump (23), and is connected on the hydraulic actuator (1)
One hydraulic pipeline and the second hydraulic pipeline are determined with the first constant displacement pump (21) and second respectively wherein the first hydraulic pipeline is equipped with two
Amount pump (22) the first hydraulic fluid port connection the first branch hydraulic pipeline and the second branch hydraulic pipeline, second hydraulic pipeline then with
First hydraulic fluid port of the third constant displacement pump (23) is connected to, and is equipped with the first solenoid valve (41) on the first hydraulic pipeline, and second
Hydraulic hydraulic pipeline is equipped with second solenoid valve (42)；Further include simultaneously with the first constant displacement pump (21), the second constant displacement pump (22),
The hydraulic accumulator (5) of the second hydraulic fluid port connection of third constant displacement pump (23)；It further include to be connect with the control motor (3)
Frequency converter (31) and the external power supply (32) being connect with frequency converter (31)；And with first solenoid valve (41) and the second electromagnetism
Valve (42) is electrically connected and is connected to the central controller (6) of control motor (3).
2. a kind of three pumps with back pressure control according to claim 1 are straight to drive electric hydrostatic actuator, it is characterised in that: also wrap
The first safety valve (51) for making hydraulic oil from the hydraulic accumulator (5) one-way flow to first hydraulic pipeline is included, and is made
Second safety valve (52) of the hydraulic oil from the hydraulic accumulator (5) one-way flow to second hydraulic pipeline.
3. a kind of three pumps with back pressure control according to claim 1 are straight to drive electric hydrostatic actuator, it is characterised in that: with
Being additionally provided on first branch hydraulic pipeline of the first hydraulic fluid port end connection of first constant displacement pump (21) keeps hydraulic oil fixed from first
Amount pump (21) flows to the first check valve (71) of hydraulic actuator (1).
4. a kind of three pumps with back pressure control according to claim 1 are straight to drive electric hydrostatic actuator it is characterized by: also wrapping
It includes the first hydraulic fluid port to be connected to the first constant displacement pump (21) and the second hydraulic fluid port end and is electrically connected simultaneously with the central controller (6)
The first pressure regulator valve (81) controlled, first pressure regulator valve (81) are bi-bit bi-pass proportioning valve.
5. a kind of three pumps with back pressure control according to claim 4 are straight to drive electric hydrostatic actuator, it is characterised in that: the
First hydraulic fluid port of a certain amount of pump (21) and the second hydraulic fluid port both ends also set up a pressure stabilizing list in parallel with the first pressure regulator valve (81)
To valve (72), the oil outlet of the pressure stabilizing check valve (72) is connected to the second hydraulic fluid port end of first constant displacement pump (21).
6. a kind of three pumps with back pressure control according to claim 1 are straight to drive electric hydrostatic actuator, it is characterised in that: also wrap
It includes the first hydraulic fluid port for being connected to the second constant displacement pump (22) and the second hydraulic fluid port end and is electrically connected and is controlled with the central controller (6)
The second pressure regulator valve (82) of system, second pressure regulator valve (82) are bi-bit bi-pass proportioning valve.
7. a kind of three pumps with back pressure control according to claim 1 are straight to drive electric hydrostatic actuator, it is characterised in that: in institute
The first hydraulic fluid port and the second hydraulic fluid port both ends for stating third constant displacement pump (23), which are also communicated with, is electrically connected simultaneously quilt with the central controller (6)
The third pressure regulator valve (83) of control, the third pressure regulator valve (23) are bi-bit bi-pass proportioning valve.
8. a kind of three pumps with back pressure control according to claim 1 are straight to drive electric hydrostatic actuator, it is characterised in that: also wrap
Include the displacement sensor (91) for being arranged on the hydraulic actuator (1) and connecting with the central controller (6), Yi Jishe
It sets at first hydraulic pipeline and the first pressure sensor (92) connecting with the central controller (6) and setting is in institute
The second pressure sensor (93) stated at the second hydraulic pipeline and connect with the central controller (6).
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910217349.3A CN109915427B (en) | 2019-03-21 | 2019-03-21 | Three-pump direct-drive electro-hydrostatic actuator with back pressure control |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910217349.3A CN109915427B (en) | 2019-03-21 | 2019-03-21 | Three-pump direct-drive electro-hydrostatic actuator with back pressure control |
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| CN109915427A true CN109915427A (en) | 2019-06-21 |
| CN109915427B CN109915427B (en) | 2021-04-02 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201910217349.3A Active CN109915427B (en) | 2019-03-21 | 2019-03-21 | Three-pump direct-drive electro-hydrostatic actuator with back pressure control |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111271327A (en) * | 2020-01-23 | 2020-06-12 | 福建工程学院 | Independent composite control hydraulic system |
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| CN108425893A (en) * | 2018-04-17 | 2018-08-21 | 福建工程学院 | A kind of distributed direct drive excavator hydraulic system of servo motor driving bivariate pump |
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| CN1817611A (en) * | 2006-03-07 | 2006-08-16 | 太原理工大学 | Injection machine system with electromechanical liquid composite control |
| CN203031283U (en) * | 2013-01-15 | 2013-07-03 | 广州大学 | Three-dimensional linkage power sliding table hydraulic control system |
| CN104675773A (en) * | 2015-03-06 | 2015-06-03 | 浙江大学 | Pure water hydraulic system of roller press for precisely controlling rolling speed and method of pure water hydraulic system for precisely controlling rolling speed |
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