CN108374809A - It is a kind of to utilize servo-controlled hydraulic synchronization circuit correction rule method for building up - Google Patents
It is a kind of to utilize servo-controlled hydraulic synchronization circuit correction rule method for building up Download PDFInfo
- Publication number
- CN108374809A CN108374809A CN201810432359.4A CN201810432359A CN108374809A CN 108374809 A CN108374809 A CN 108374809A CN 201810432359 A CN201810432359 A CN 201810432359A CN 108374809 A CN108374809 A CN 108374809A
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- Prior art keywords
- servo
- hydraulic
- hydraulic cylinder
- valve
- rack
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Classifications
-
- 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
- F15B11/16—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors
- F15B11/22—Synchronisation of the movement of two or more servomotors
-
- 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
- F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
- F15B2211/71—Multiple output members, e.g. multiple hydraulic motors or cylinders
Abstract
The invention discloses a kind of using servo-controlled hydraulic synchronization circuit correction rule method for building up, is transmission deviation delta x using the hydraulic synchronization circuit correction rule method for building up of servo valve controlpWith servo valve spool displacement xvAccurate transmission function, the present invention feeds back hydraulic cylinder using rack and pinion assembly and servo-actuated valve module, and the synchronous journey error for offsetting hydraulic cylinder, realizes the reverse sync effect of hydraulic cylinder, synchronous precision is higher, is applicable to step reverse sync hydraulic circuit with high accuracy of seeking common ground.
Description
Technical field
It is specifically a kind of same using servo-controlled hydraulic pressure the present invention relates to hydraulic system synchronous control technique field
Walk circuit correction rule method for building up.
Background technology
In hydraulic system, can usually encounter two hydraulic actuators with the displacement of identical (or opposite) or it is identical (or
Opposite) speed carries out operation, it is necessary to synchronization loop is used, currently, realizing the same of two hydraulic cylinders in hydraulic system
The measure in step circuit mainly has two kinds of mechanical forced synchronism and hydraulic synchronization：It is that synchronization can that mechanical forced, which synchronizes biggest advantage,
Lean on, but the hydraulic cylinders that its disadvantage is exactly two synchronous operations can be influenced by another hydraulic cylinder, when work will produce compared with
Big mechanicals efforts bring the failure pulled etc to hydraulic cylinder；
Hydraulic synchronization mainly realizes the speed sync between two hydraulic cylinders using hydraulic control, same to reach position
The purpose of step, but hydraulic cylinder leakage, foozle will appear using hydraulic control synchronization loop and block the problems such as uneven so that
Synchronization accuracy is not high, and synchronous effect is undesirable.
Invention content
According to the above-mentioned deficiencies of the prior art, the technical problem to be solved by the present invention is to propose it is a kind of utilize SERVO CONTROL
Hydraulic synchronization circuit rectify a deviation rule method for building up.
The present invention solves its technical problem using following technical scheme to realize：
A kind of to utilize servo-controlled hydraulic synchronization circuit correction rule method for building up, the hydraulic synchronization circuit includes liquid
Pressure power component, No.1 hydraulic cylinder, No. two hydraulic cylinders, rack and pinion assembly and servo-actuated valve module, hydraulic power pack is No.1
The work of hydraulic cylinder, No. two hydraulic cylinders, servo-actuated valve module provides power, and rack and pinion assembly includes No.1 rack and No. two teeth
Item, No.1 rack and No. two racks are reversely setting up and down, and No.1 rack is connected with the load end of No.1 hydraulic cylinder, No. two racks
It is connected with the load end of No. two hydraulic cylinders, gear is equipped between No.1 rack and No. two racks, servo-actuated valve module includes two-way
Servo valve and connecting rod are shunted, bidirectional shunt servo valve includes valve block and servo-actuated spool, and servo-actuated spool is slidably connected in valve block, even
The middle part of bar is mounted on by hinged mode on bearing, and one end and the gear of connecting rod are rotatablely connected, and the other end of connecting rod passes through
Hinged mode is connected with servo-actuated spool, and valve block is equipped with oil inlet, No.1 oil outlet and No. two oil outlets, No.1 oil outlet
It is connected with No.1 hydraulic cylinder, No. two oil outlets are connected with No. two hydraulic cylinders, and oil inlet is connected with hydraulic power pack, entangles
The specific method that inclined rule is established is：
(1) flow equation that follow move pilot valve is established according to the flow of No.1 hydraulic cylinder and No. two hydraulic cylinders obtains load stream
A kind of expression-form of amount；
(2) expression formula of load flow is linearized；
(3) the Flow continuity equation for establishing No.1 hydraulic cylinder and No. two hydraulic cylinders obtains another table of load flow
Up to formula；
(4) hydraulic cylinder and the equilibrium equation of load are established；
(5) two kinds of expression-forms of load flow and hydraulic cylinder and the equilibrium equation of load are subjected to pull-type transformation, obtained
Go out to be driven the input quantity expression formula of deviation；
(6) the input quantity expression formula for being driven deviation is simplified, obtains transmission deviation to being servo-actuated the accurate of spool displacement
Transmission function.
Controlled quentity controlled variable is servo-actuated spool displacement, and controlled variable is transmission deviation, when the position of No.1 hydraulic cylinder and No. two hydraulic cylinders
When moving of different sizes, displacement deviation is generated to servo-actuated spool by rack and pinion assembly, is changed by being servo-actuated the displacement of spool
The valve port orifice size of No.1 oil outlet and No. two oil outlets, and then change the stream into No.1 hydraulic cylinder and No. two hydraulic cylinders
Amount, finally so that the displacement of two hydraulic cylinders is identical.
Hydraulic power pack includes fuel tank, filter, constant displacement pump, motor, overflow valve and hand-operated direction valve, motor
Output end is connected with constant displacement pump, provides power for the work of constant displacement pump, fuel tank, constant displacement pump, overflow valve, changes filter manually
Oil pipe is passed sequentially through to valve to be connected.
The beneficial effects of the invention are as follows：
The present invention feeds back hydraulic cylinder using rack and pinion assembly, and the synchronous journey error for offsetting hydraulic cylinder, real
Show the reverse sync effect of hydraulic cylinder, synchronous precision is higher, is applicable to step reverse sync hydraulic pressure time with high accuracy of seeking common ground
Road.
Description of the drawings
The content expressed by this specification attached drawing and the label in figure are briefly described below：
Fig. 1 is the principle of the present invention schematic diagram；
Fig. 2 is the control system block diagram of the present invention.
Specific implementation mode
Below by the description to embodiment, the shape of for example involved each component of specific implementation mode of the invention, structure
It makes, the mutual alignment between each section and connection relation, the effect of each section and operation principle, manufacturing process and the side of operating with
Method etc., is described in further detail, completeer to help those skilled in the art to have the inventive concept of the present invention, technical solution
Whole, accurate and deep understanding.
It is a kind of to utilize servo-controlled hydraulic synchronization circuit correction rule method for building up, the specific steps are：
(1) flow equation of follow move pilot valve is established
qL=q1+q2 (1)
In formula (1) (2) (3) (4), qL：Load flow；q1：Into the flow of hydraulic cylinder 1；q2：Into the stream of hydraulic cylinder 2
Amount；Cd：Discharge coefficient；A1：The flow area of restriction 1；A2：The flow area of restriction 2；ρ：The density of hydraulic oil；ps：For
Oil pressure；p1：The pressure of No.1 hydraulic cylinder；p2The pressure of No. two hydraulic cylinders.
(2) formula (4) are linearized
qL=Kqxv-KcpL (5)
In formula (5), Kq：DefinitionReferred to as flow gain
Coefficient, Kc：DefinitionReferred to as flow-pressure coefficient；
xv：Servo valve spool displacement；pL：Load pressure.
(3) hydraulic cylinder Flow continuity equation is established
qL=q1+q2；Δ xp=xp1-xp2；Vt=V1+V2 (8)
After arrangement
In formula (6) (7) (8) (9) (10), Ap：Hydraulic cylinder piston rod rodless cavity effective area；xp1：No.1 hydraulic cylinder piston
The displacement of bar；V1：The volume of No.1 hydraulic cylinder oil suction chamber；Cip：The hydraulic cylinder interior leakage coefficient of leakage；V1：No.1 hydraulic cylinder oil suction chamber
Volume (including valve, connecting pipe and oil suction chamber)；βe：Effective volume elasticity modulus (includes the machine of fluid, connecting pipe and cylinder body
Tool flexibility)；xp2：The displacement of No. two hydraulic cylinder piston rods；V2：The volume of No. two hydraulic cylinder oil suction chambers；Δxp：It is driven deviation；Vt：
Total compression volume.
(4) hydraulic cylinder and the equilibrium equation of load are established
The dynamic characteristic of Hydraulic power units is influenced by load characteristic.Load force generally comprises inertia force, viscous damping
Power, elastic force and arbitrary outer load force.
The power output of hydraulic cylinder and the equilibrium equation of load force are
M in formula (7)t：Piston and load are converted to the gross mass on piston；Bp：Piston and the viscous damping coefficient of load；
K：Spring loaded rigidity；FL：Act on the arbitrary outer load force on piston.
(5) Laplace transformation is carried out to equation (5) (10) (11)
QL=KqXv-KcPL (12)
ApPL=mts2ΔXp+BpsΔXp+KΔXp+FL (14)
(6) simultaneous equations (12) (13) (14) eliminate intermediate variable QLAnd PLObtain formula (15)
(7) transmission function simplifies
The load of servo-drive system is based on inertia load, very without elastic load or elastic load in many cases
It is small to ignore.In addition, by hydraulic cylinder interior leakage coefficient of leakage CipAnd viscous damping coefficient BpGenerated speedThan the movement velocity s Δs X of pistonpSmall is more, therefore above formula can be ignored.
In the case where K=0 above formulas are ignored, formula (15) can be reduced to
Or
ω in formulah- hydraulic natural frequency
ζh- hydraulic damping ratio
To input instruction Xv transmission function be
To exogenous disturbances FLTransmission function be
Operation principle is：
Fuel feeding branch drives hydraulic pump 3 that the hydraulic oil in fuel tank 1 is supplied hand-operated direction valve 6 by motor 4, presses hand
The handle of dynamic reversal valve 6, makes the left end station of hand-operated direction valve 6 access circuit, and hydraulic oil is entered two-way by hand-operated direction valve 6
In the cavity for shunting servo valve 13, the spool 16 of bidirectional shunt servo valve 13 is in the centre position of cavity at this time, i.e. No.1 goes out
Hydraulic fluid port 14 and No. two 15 valve port areas of section of oil outlet are equal, and No.1 liquid is flowed by No.1 oil outlet 14 and No. two oil outlets 15
The flow of cylinder pressure 8 and No. two hydraulic cylinders 7 is equal, since the specification of two hydraulic cylinders is identical, so when two hydraulic cylinders movement
Velocity magnitude is equal, and direction is on the contrary, movement velocity size with two hydraulic cylinders joining No.1 rack 9 and No. two racks 11
Equal, direction is reversed on the contrary, therefore tooth since the movement velocity of two racks at this time is equal in magnitude on the contrary, moved with moving gear 10
The axle center of wheel 10 is not subjected to displacement.
When the speed of No.1 hydraulic cylinder 8 is more than the speed of No. two hydraulic cylinders 7, the axle center of No.1 rack drives gear 10 to
A left side is subjected to displacement, and by the effect of connecting rod 12, so that servo-actuated spool 16 is moved right, is reduced the valve port section of No.1 oil outlet 14
Area increases the valve port area of section of No. two oil outlets 15 so that the flow for entering No.1 hydraulic cylinder 8 reduces, No.1 hydraulic pressure
The speed of cylinder 8 reduces, and the flow into No. two hydraulic cylinders 7 increases, and the speed of No. two hydraulic cylinders 7 increases, until two hydraulic cylinders
Velocity magnitude it is equal until.
Similarly, when the speed of No.1 hydraulic cylinder 8 is less than the speed of No. two hydraulic cylinders 7, No. two racks 11 are with moving gear 10
Axle center be subjected to displacement to the right, by the effect of connecting rod 12, so that servo-actuated spool 16 is moved to the left, increase No.1 oil outlet 14
Valve port area of section reduces the valve port area of section of No. two oil outlets 15 so that and the flow for entering No.1 hydraulic cylinder 8 increases,
The speed of No.1 hydraulic cylinder 8 increases, and the flow into No. two hydraulic cylinders 7 reduces, and the speed of No. two hydraulic cylinders 7 reduces, until two
Until the velocity magnitude of a hydraulic cylinder is equal.
As shown in Figure 1, the displacement of No.1 hydraulic cylinder 8 is xp1, to the left, the displacement of No. two hydraulic cylinders 7 is x in directionp2, direction
To the right, work as xp1>xp2When, the axle center of gear 10 will be subjected to displacement to the left, and transmission deviation delta x can be acquired according to theory of mechanicsp：
Δxp=xp1-xp2 (23)
Further according to the flow equation of follow move pilot valve, hydraulic cylinder Flow continuity equation, the dynamic balance side of hydraulic cylinder and load
Servo valve flow equation after journey and Laplace transformation, hydraulic cylinder Flow continuity equation and hydraulic cylinder and the power of load are flat
Weigh equation, to obtain transmission deviation delta xpWith with servo-actuated spool displacement xvThe accurate transmission function.
The present invention is exemplarily described above, it is clear that present invention specific implementation is not subject to the restrictions described above,
As long as using the improvement of the various unsubstantialities of inventive concept and technical scheme of the present invention progress, or not improved this is sent out
Bright design and technical solution directly applies to other occasions, within protection scope of the present invention.The protection of the present invention
Range should be determined by the scope of protection defined in the claims.
Claims (3)
1. a kind of utilizing servo-controlled hydraulic synchronization circuit correction rule method for building up, it is characterised in that：The hydraulic synchronization
Circuit includes hydraulic power pack, No.1 hydraulic cylinder, No. two hydraulic cylinders, rack and pinion assembly and servo-actuated valve module, hydraulic power
Component is No.1 hydraulic cylinder, the work of No. two hydraulic cylinders, servo-actuated valve module provides power, and rack and pinion assembly includes No.1 rack
With No. two racks, No.1 rack and No. two racks are reversely setting up and down, and No.1 rack is connected with the load end of No.1 hydraulic cylinder,
No. two racks are connected with the load end of No. two hydraulic cylinders, and gear is equipped between No.1 rack and No. two racks, are servo-actuated valve module
Including bidirectional shunt servo valve and connecting rod, bidirectional shunt servo valve includes valve block and servo-actuated spool, and it is sliding in valve block to be servo-actuated spool
The middle part of dynamic connection, connecting rod is mounted on by hinged mode on bearing, and one end and the gear of connecting rod are rotatablely connected, connecting rod it is another
One end is connected by hinged mode with servo-actuated spool, valve block be equipped with oil inlet, No.1 oil outlet and No. two oil outlets, one
Number oil outlet is connected with No.1 hydraulic cylinder, and No. two oil outlets are connected with No. two hydraulic cylinders, oil inlet and hydraulic power pack
It is connected, the specific method that correction rule is established is：
(1) flow equation that follow move pilot valve is established according to the flow of No.1 hydraulic cylinder and No. two hydraulic cylinders, obtains load flow
A kind of expression-form；
(2) expression formula of load flow is linearized；
(3) the Flow continuity equation for establishing No.1 hydraulic cylinder and No. two hydraulic cylinders obtains another expression formula of load flow；
(4) hydraulic cylinder and the equilibrium equation of load are established；
(5) two kinds of expression-forms of load flow and hydraulic cylinder and the equilibrium equation of load are subjected to pull-type transformation, obtain biography
The input quantity expression formula of dynamic deviation；
(6) the input quantity expression formula for being driven deviation is simplified, obtains the accurate transmission of the transmission deviation to servo-actuated spool displacement
Function.
2. according to claim 1 using servo-controlled hydraulic synchronization circuit correction rule method for building up, feature exists
In：The controlled quentity controlled variable of the method is servo-actuated spool displacement Xv, and controlled variable is transmission deviation delta Xp, when No.1 hydraulic cylinder and No. two
When the displacement difference of hydraulic cylinder, displacement deviation is generated to servo-actuated spool by rack and pinion assembly, by being servo-actuated spool
Displacement changes the valve port orifice size of No.1 oil outlet and No. two oil outlets, and then changes and enter No.1 hydraulic cylinder and No. two liquid
The flow of cylinder pressure, finally so that the displacement of two hydraulic cylinders is identical.
3. according to claim 1 using servo-controlled hydraulic synchronization circuit correction rule method for building up, feature exists
In：The hydraulic power pack includes fuel tank, filter, constant displacement pump, motor, overflow valve and hand-operated direction valve, motor
Output end is connected with constant displacement pump, and power is provided for the work of constant displacement pump, fuel tank, filter, constant displacement pump, overflow valve and changes manually
Oil pipe is passed sequentially through to valve to be connected.
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| CN201810432359.4A CN108374809B (en) | 2018-05-08 | 2018-05-08 | A kind of method for building up of servo-controlled hydraulic synchronization circuit correction rule |
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| CN201810432359.4A CN108374809B (en) | 2018-05-08 | 2018-05-08 | A kind of method for building up of servo-controlled hydraulic synchronization circuit correction rule |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2020170883A1 (en) * | 2019-02-19 | 2020-08-27 | 株式会社豊田自動織機 | Ship steering device |
| CN113431814A (en) * | 2021-06-17 | 2021-09-24 | 江苏科技大学 | Synchronous control method based on parallel motion of multiple hydraulic cylinders of heave compensation platform |
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| CN113431814B (en) * | 2021-06-17 | 2022-12-30 | 江苏科技大学 | Synchronous control method based on parallel motion of multiple hydraulic cylinders of heave compensation platform |
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| CN108374809B (en) | 2019-07-30 |
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