CN105508330A - Electromagnet-driven digital hydraulic servo actuator - Google Patents
Electromagnet-driven digital hydraulic servo actuator Download PDFInfo
- Publication number
- CN105508330A CN105508330A CN201610015318.6A CN201610015318A CN105508330A CN 105508330 A CN105508330 A CN 105508330A CN 201610015318 A CN201610015318 A CN 201610015318A CN 105508330 A CN105508330 A CN 105508330A
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- CN
- China
- Prior art keywords
- hydraulic
- oil
- electromagnet
- actuator
- power unit
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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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
- F15B11/17—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors using two or more pumps
-
- 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
- F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
- F15B21/08—Servomotor systems incorporating electrically operated control means
Abstract
The invention discloses an electromagnet-driven digital hydraulic servo actuator. A hydraulic power unit in the electromagnet-driven digital hydraulic servo actuator is composed of an electromagnet, a piston, a cone valve, a cylinder body and the like. The electromagnet moves to drive the piston to move, thereby pressurizing the hydraulic oil; and the extruded hydraulic oil provides power for the actuator. The oil duct of the actuator is provided with a bidirectional hydraulic lock, thereby preventing the actuator from losing control due to power cut and other reasons in the working engineering. An energy storage device on the mechanism oil duct stores energy in the extending stroke process, and releases the energy in the return process, thereby implementing the quick-return motion of the actuator. A servocontrol unit comprises a displacement sensor, which is installed on the actuator and used for feeding the speed and displacement of the actuator back to a control system; and the control system sends out a corresponding control signal, thereby implementing digital servo control. By using the integrated hydraulic power unit as a power source, the electromagnet-driven digital hydraulic servo actuator has the advantages of small size and high thrust, has flame resistance after being sealed, can easily implement digital servo control, and can control the cost on a lower level.
Description
Technical field
The present invention relates to a kind of digital hydraulic servo final controlling element (hereinafter referred to as final controlling element) based on solenoid actuated.More precisely, a kind of integrated type, high precision electro hydraulic servo actuator by forming based on the large module of the hydraulic power unit of solenoid actuated, hydraulic executing system and servo control unit three is related to.
Background technique
Final controlling element refers to and uses liquid, gas, electric power or other energy by certain mechanical device by the class mechanism of energy conversion for driving.Hydraulic actuator is a kind of with the device of high pressure liquid force feed actuate actuators motion.Relative to other final controlling element, it has the advantages such as inertia is little, reaction is fast, power is huge, operate steadily.But existing hydraulic actuator is owing to adopting independent hydraulically controlled pump as power source, the integrated operational amplifier that adopts controls more, causes that its existence and stability is poor, control accuracy is low, volume is large, anti-interference is poor, high in cost of production shortcoming.
Along with the development of industrial technology, the requirement for the control accuracy of final controlling element, intelligent level, the stability of a system also improves constantly.Now commercially for high-end final controlling element common demands, it has high reliability, permanent protective property, high explosive-proof grade, high-intelligentization, compact, the feature such as lightweight, and conventional hydraulic final controlling element is difficult to meet the demand simultaneously.
Summary of the invention
The present invention proposes a kind of digital hydraulic servo final controlling element based on solenoid actuated.Its basic principle is that the hydraulic power unit using electromagnet (comprising proportion electro-magnet and switch electromagnet) to drive provides power for a set of integrated type hydraulic servo-actuator, makes it to become a set of electro-hydraulic servo actuator possessing the advantages such as highi degree of accuracy, integration, volume are little, low cost.
In order to realize above-mentioned functions requirement, the present invention takes following technological scheme:
The present invention includes the module such as hydraulic power unit, oil circuit control, execution oil hydraulic cylinder, solenoid directional control valve, bidirectional hydraulic lock, accumulator, displacement transducer, servocontroller, power amplification unit based on solenoid actuated.
The hydraulic power unit of described solenoid actuated, as the power source of this final controlling element, comprises a micro miniature hydraulic pump based on proportion electro-magnet driving and multiple micro miniature hydraulic pump driven based on switch electromagnet.
The mechanical structure of described hydraulic power unit comprises the parts such as hydraulic pump body, electromagnet (comprising proportion electro-magnet and switch electromagnet two kinds), motion plunger, unidirectional cone valve, inlet (outlet).
The described micro miniature hydraulic pump output discharge capacity controllable precise driven based on proportion electro-magnet, may be used for volumetric speed control.And the described micro miniature hydraulic pump output discharge capacity based on switch electromagnet driving immobilizes.
Oil hydraulic cylinder, oil circuit control, solenoid directional control valve, bidirectional hydraulic lock and accumulator constitute hydraulic actuating unit.
Displacement transducer, servocontroller, power amplification unit constitute servo control unit.
Described bidirectional hydraulic lock is made up of two Pilot operated check valves, and on the oil-feed oil circuit being arranged in oil hydraulic cylinder respectively and oil return circuit, the Pilot operated check valve on each oil circuit is all controlled by the oil pressure on another oil circuit.
The described hydraulic power unit based on solenoid actuated and solenoid directional control valve are all controlled by servocontroller, to realize the servocontrol of whole actuator motions state.
Its working principle is as follows:
In hydraulic power unit, produce periodic to-and-fro motion after electromagnet energising, solenoid actuated plunger reciprocates, makes pump chamber generating period change.When electromagnet extends, pump chamber compresses, and oil pressure increases, and oil outlet unidirectional cone valve pressurized is opened, and filler opening unidirectional cone valve pressurized is closed simultaneously, and now, hydraulic oil is forced out in pump chamber.Otherwise when electromagnet shrinks, the hydraulic oil in fuel tank is inhaled in pump chamber.Circulation like this repeatedly, becomes one for system and provides the micro miniature hydraulic pump of power.
The high pressure oil that hydraulic power unit exports enters oil hydraulic cylinder along in-line, and promote piston rod movement, meanwhile, accumulator energy storage, and the Pilot operated check valve of fuel-displaced oil circuit is opened by the high pressure oil in in-line, make the low pressure oil in oil hydraulic cylinder the other end chamber flow back to fuel tank, final controlling element is to an end motion.When selector valve controlled oppositely after, hydraulic oil moving direction is exchanged, and final controlling element is to motion in the other direction, and in return stroke, accumulator releases energy, and realizes quick-return motion.When selector valve is in middle rest position time, bidirectional hydraulic lock is locked by oil circuit, and final controlling element holding position is constant.
In a control unit, sensor gathers the motion state signal (speed of piston rod in oil hydraulic cylinder, the signals such as displacement), feed back to servo-control system, control system is according to the deviation of oil hydraulic cylinder actual motion state and desired motion state, regulate the proportion electro-magnet in hydraulic power unit to make corresponding sports again, thus reach control objectives.
Beneficial effect of the present invention:
1, the present invention adopt based on the hydraulic power unit of solenoid actuated be power source, volume reduces greatly, be easy to carry, install, and have explosion prevention function after encapsulation.
2, hydraulic power unit total displacement is adjustable flexibly, and is controlled by servo-control system, makes to export discharge capacity controllable precise, thus accurately can control movement velocity and the displacement of final controlling element.
3, the output of electromagnet is through hydraulic conversion, can realize large ouput force as required.
4, the hydraulic power unit of adoption rate solenoid actuated of the present invention is as the power source of final controlling element, compares traditional power source, more easily realizes digital control.
5, while stating function in realization, the cost of this actuating device is significantly less than similar final controlling element, can realize large output and digital stream network by low cost.
Accompanying drawing explanation
Fig. 1 is this final controlling element overall schematic.
Fig. 2 is this final controlling element power source, i.e. the hydraulic power unit sectional view of solenoid actuated.
Embodiment
Below in conjunction with accompanying drawing, the present invention is further described.
As shown in Figure 1, the digital hydraulic servo final controlling element of solenoid actuated mainly contains the parts formation such as hydraulic power unit 1, solenoid directional control valve 2, bidirectional hydraulic lock 3, execution oil hydraulic cylinder 4, displacement transducer 5, power amplifier 6, control system 7, accumulator 8, automatically controlled two Twoway valvess 9 of solenoid actuated.
As shown in Figure 2, the hydraulic power unit of solenoid actuated is by plunger 11, electromagnet 12, the unit pump housing 13, filler opening 14, the passive unidirectional cone valve 15 of filler opening, oil outlet 17, and oil outlet is by unidirectional formation such as mantle valve 16 grade.
The hydraulic power unit 1 that this final controlling element is driven by integrated electromagnets provides power, and hydraulic power unit has that small-scale liquid press pump is integrated to be formed.In diagram, miniature pump B, C, D of the miniature pump A that hydraulic power unit is driven by proportion electro-magnet and switch electromagnet driving are integrated to be formed.In final controlling element drive-in step, the outside pump oil of oil hydraulic pump, electrically-controlled valve 9 is in bottom, accumulator energy storage, selector valve 2 moves right, and pumps hydraulic oil oil circuit and left side Pilot operated check valve on the left of selector valve 2, enter in figure on the left of oil hydraulic cylinder, right side Pilot operated check valve opened by hydraulic oil simultaneously.Perform hydraulic oil backflow on the right side of oil hydraulic cylinder.
Hydraulic cylinder piston drives piston rod movement, and displacement transducer 5 is measured piston rod movement speed and Displacement Feedback to numerical control system 7 and formed closed-loop feedback.After the signal of displacement transducer 5 returns numerical control system 7, system is according to the program pre-set, judge following motion state, necessary switch motion is carried out to switching mode electromagnet, its amount of exercise of comparative example Electromagnetic Control, thus the motion of control pump inner plunger, change and export discharge capacity, thus control the motion of final controlling element, according to the ratio of pump inner plunger area S1 and hydraulic implement cylinders piston area S2, the concrete numerical value of flow needing adjustment can be determined.
When numerical control system sends the reversing motion of SC sigmal control oil hydraulic cylinder, selector valve is left side motion in figure, and oil hydraulic cylinder oil-feed direction and fuel-displaced direction exchange, and piston is left side motion in figure.
When numerical control system makes selector valve be in neutral position, oil circuit is locked, and now final controlling element is subject to external force and also can not moves.
In final controlling element return stroke, when automatically controlled two Twoway valvess 9 are controlled become upper path time, accumulator 8 outwards release pressure, final controlling element accelerated motion, realizes quick-return motion, when final controlling element is in rise process, automatically controlled two Twoway valvess 9 are in bottom, accumulator 8 energy storage.
Power in this final controlling element is from integrated hydraulic power unit.This hydraulic power unit comprises a micro miniature hydraulic pump A based on proportion electro-magnet driving and multiple micro miniature hydraulic pump B driven based on switch electromagnet, C, D etc.Only adopt a micro miniature hydraulic pump driven based on proportion electro-magnet, for accurate hydraulic control oil discharge capacity.Adopt this compound mode can realize the accurate control of actuator motions state, reduce controlling cost of system simultaneously.The present invention is described for 4 micro miniature hydraulic pumps, wherein 3, switch electromagnet type (in Fig. 1 B, C, D), and its discharge capacity is
q.1, proportion electro-magnet type (in Fig. 1 A), discharge capacity is at 0-
qbetween controllable precise.Then the total displacement of this hydraulic power unit is at 0-4
qbetween controllable precise.As needed 3.25
qdischarge capacity export, then need controller that 3 switch electromagnet types are all opened, simultaneously control ratio electromagnet type exports 0.25
qdischarge capacity, then system just achieves 3.25
qflow export.
As preferably, oil circuit increasing bidirectional hydraulic lock can ensure that when final controlling element does not move actuator position keeps, even if power-off also can not slippage in lifting heavy process, strengthens the reliability of final controlling element.
As preferably, this final controlling element adopts the encapsulation of high tensile aluminium alloy shell, while ensureing that internal structure is subject to protection, has explosion-proof performance, and slimmer and more graceful relative to steel casting shell.
The single microminiature pump based on solenoid actuated comprises a filler opening 14, oil outlet 17, and is equipped with two passive unidirectional cone valves.Electromagnet 12 and plunger 11 link, and form a closed chamber between plunger 11 and the pump housing.When magnet control plunger moves upward, the volume of enclosed cavity reduces, and oil pressure raises, and now mitre velve 15 pressurized of filler opening is closed, and unidirectional cone valve 16 pressurized of oil outlet is opened, and hydraulic oil is forced out from oil outlet 17, forms power.When the take-off lever of control system control ratio electromagnet 12 moves downward, then plunger 11 is driven and moves downward, and sealed chamber's volume becomes large, forms negative pressure.Now unidirectional cone valve 16 pressurized of oil outlet is closed, and unidirectional cone valve 15 pressurized of filler opening is opened, and it is that force feed is prepared next time that hydraulic oil flows back to chamber, so moves in circles.
To sum up, the power unit that power unit and switch electromagnet that proportion electro-magnet drives drive is integrated with while the power source in the present invention, the lower cost of maintenance while achieving large output, accurately control discharge capacity.
Switch electromagnet in the present invention and proportion electro-magnet realize digital control simultaneously, thus realize the accurate servocontrol for final controlling element.
Electromagnet power source in the present invention, through hydraulic conversion, can realize very large ouput force.
Final controlling element aluminum alloy in the present invention encapsulates, and after having encapsulated, volume is little and possess explosion-proof performance.
Bidirectional hydraulic lock in the present invention can ensure that final controlling element is stablized in working procedure, can not occur reversing motion or out of control because of problems such as power-off.
Technological scheme of the present invention is not limited to the restriction of above-mentioned specific embodiment, the technology distortion that every technological scheme according to the present invention is made, and all falls within protection scope of the present invention.
Claims (1)
1. the digital hydraulic servo final controlling element of solenoid actuated, primarily of hydraulic power unit, electrically-controlled valve, execution oil hydraulic cylinder, accumulator, bidirectional hydraulic lock, displacement transducer, power amplifier, numerical control system, is characterized in that:
Described hydraulic power unit oil outlet is connected with electrically-controlled valve, filler opening is connected with fuel tank, electro hydraulic valve is connected with bidirectional hydraulic lock, and bidirectional hydraulic lock is connected with oil outlet with execution hydraulic cylinder oil inlet, and displacement transducer is fixed on and performs on oil hydraulic cylinder; Accumulator is connected by the fuel-displaced oil circuit of described electrically-controlled valve and hydraulic power unit;
Described hydraulic power unit, electrically-controlled valve all accept numerical control system and send via the control of power amplifier amplifying signal, and displacement transducer is by signal feed back to numerical control system, and whole final controlling element realizes closed loop control;
Described hydraulic power unit comprises an oil hydraulic pump based on proportion electro-magnet driving and multiple oil hydraulic pump driven based on switch electromagnet, and each oil hydraulic pump comprises electromagnet, cylinder body, piston, filler opening, oil outlet, filler opening mitre velve, oil outlet mitre velve;
Electromagnet is connected with piston, and cylinder body is divided into upper and lower two spaces by piston, and upper chamber is connected with oil outlet with filler opening respectively, and filler opening and oil outlet are respectively arranged with filler opening mitre velve, oil outlet mitre velve;
Described bidirectional hydraulic lock comprises two Pilot operated check valves, is arranged in fuel-displaced oil circuit and oil return circuit respectively, one-way passage when Pilot operated check valve oil circuit control does not have pressure, ensure final controlling element rise and fall weight time can not drop.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610015318.6A CN105508330A (en) | 2016-01-12 | 2016-01-12 | Electromagnet-driven digital hydraulic servo actuator |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610015318.6A CN105508330A (en) | 2016-01-12 | 2016-01-12 | Electromagnet-driven digital hydraulic servo actuator |
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| Publication Number | Publication Date |
|---|---|
| CN105508330A true CN105508330A (en) | 2016-04-20 |
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ID=55716552
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201610015318.6A Pending CN105508330A (en) | 2016-01-12 | 2016-01-12 | Electromagnet-driven digital hydraulic servo actuator |
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| CN (1) | CN105508330A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109555738A (en) * | 2019-01-21 | 2019-04-02 | 何旺成 | Digital Control water hydraulic canonical system circuit |
| CN111502950A (en) * | 2020-04-27 | 2020-08-07 | 山东理工大学 | Efficient high-precision bidirectional flow distribution method for linear hydraulic pump |
| CN111720389A (en) * | 2020-07-06 | 2020-09-29 | 长沙理工大学 | Combined hydraulic potential energy regeneration system |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109555738A (en) * | 2019-01-21 | 2019-04-02 | 何旺成 | Digital Control water hydraulic canonical system circuit |
| CN111502950A (en) * | 2020-04-27 | 2020-08-07 | 山东理工大学 | Efficient high-precision bidirectional flow distribution method for linear hydraulic pump |
| CN111720389A (en) * | 2020-07-06 | 2020-09-29 | 长沙理工大学 | Combined hydraulic potential energy regeneration system |
| CN111720389B (en) * | 2020-07-06 | 2022-09-06 | 长沙理工大学 | Combined hydraulic potential energy regeneration system |
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Application publication date: 20160420 |
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