CN104819178A - Pressure follow-up servo valve - Google Patents
Pressure follow-up servo valve Download PDFInfo
- Publication number
- CN104819178A CN104819178A CN201510119642.8A CN201510119642A CN104819178A CN 104819178 A CN104819178 A CN 104819178A CN 201510119642 A CN201510119642 A CN 201510119642A CN 104819178 A CN104819178 A CN 104819178A
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- CN
- China
- Prior art keywords
- entrance
- pressure
- bridge
- housing
- cock body
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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
- F15B13/00—Details of servomotor systems ; Valves for servomotor systems
- F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
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- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Servomotors (AREA)
Abstract
The invention relates to a pressure follow-up servo valve. The pressure follow-up servo valve comprises a shell and a valve core positioned in the shell, and further comprises a first pressure reducing half bridge. The pressure follow-up servo valve is smaller in volume, and can obtain an outlet oil pressure forming a certain linear relation with an inlet oil pressure through controlling the output force of a power device.
Description
Technical field
The present invention relates to servovalve field, particularly a kind of pressure follow-up type servovalve.
Background technique
Hydraulic control servovalve can after accepting electric simulation signal, corresponding flow and the oil pressure exporting modulation.It is electro-hydraulic converting element, is also power amplification element, and low power faint electrical input signal can be converted to powerful hydraulic energy (flow and oil pressure) and export by it.In electrohydraulic servo system, electric part and hydraulic part couple together by it, and the conversion and the hydraulic pressure that realize electric liquid signal amplify.Electrohydraulic control is the core that electrohydraulic servo system controls.
Shown in Figure 1, be the structural drawing of existing oil pressure follow-up type servovalve.The pressure follow-up type servovalve of this kind of structure, can control its outlet oil pressure P
sfollow its entrance oil pressure P
a, and reach outlet oil pressure when state of equilibrium equal with entrance oil pressure.
But the volume of existing pressure follow-up type servovalve is comparatively large, cause its Applicable scope by restriction to a certain extent.
Summary of the invention
Provide hereinafter about brief overview of the present invention, to provide about the basic comprehension in some of the present invention.Should be appreciated that this general introduction is not summarize about exhaustive of the present invention.It is not that intention determines key of the present invention or pith, and nor is it intended to limit the scope of the present invention.Its object is only provide some concept in simplified form, in this, as the preorder in greater detail discussed after a while.
A main purpose of the present invention is to provide a kind of pressure follow-up type servovalve, its small volume, and outlet oil pressure becomes certain linear relationship with entrance oil pressure.
According to an aspect of the present invention, a kind of pressure follow-up type servovalve, comprises housing and the spool being positioned at housing, also comprises the first decompression half-bridge;
Wherein,
Described spool is asymmetric plunger, comprise the post portion of stretching out outside described housing and be connected with described post portion and be positioned at the piston part of described housing, described piston part has peripheral groove, described piston part is divided into the first cock body and the second cock body by described peripheral groove, and described first cock body and described second cock body and described housing form Spielpassung;
Described housing is divided into the rod chamber including described post portion by described spool, the intermediate cavity between described first cock body and described second cock body, and rodless cavity;
Described housing is provided with the first entrance, the second entrance and the 3rd entrance;
Described first entrance is for receiving external hydraulic input, and described second entrance is connected with external fuel tank;
Described first entrance is also connected with the described first first end reducing pressure half-bridge, also reduce pressure with described first second end of half-bridge of described second entrance is connected, described 3rd entrance is connected with the described first middle end reducing pressure half-bridge, for inputing to described rodless cavity by after described external hydraulic input dividing potential drop;
Described housing is also provided with outlet and feedback port, described feedback port is used for described outlet hydraulic to feed back to described rod chamber.
Pressure follow-up type servovalve of the present invention, small volume, can obtain the outlet oil pressure becoming some linear with entrance oil pressure.
Accompanying drawing explanation
Below with reference to the accompanying drawings illustrate embodiments of the invention, above and other objects, features and advantages of the present invention can be understood more easily.Parts in accompanying drawing are just in order to illustrate principle of the present invention.In the accompanying drawings, same or similar technical characteristics or parts will adopt same or similar reference character to represent.
Fig. 1 is the structural drawing of a kind of mode of execution of existing pressure follow-up type servovalve;
Fig. 2 is the structural drawing of a kind of mode of execution of pressure follow-up type servovalve of the present invention;
Fig. 3 is the pressure follow-up type servovalve spool of Fig. 2 schematic diagram when being positioned at right position;
Fig. 4 is the pressure follow-up type servovalve spool of Fig. 2 schematic diagram when being positioned at left position.
Embodiment
With reference to the accompanying drawings embodiments of the invention are described.The element described in an accompanying drawing of the present invention or a kind of mode of execution and feature can combine with the element shown in one or more other accompanying drawing or mode of execution and feature.It should be noted that for purposes of clarity, accompanying drawing and eliminate expression and the description of unrelated to the invention, parts known to persons of ordinary skill in the art and process in illustrating.
Shown in Figure 2, be the structural drawing of a kind of mode of execution of pressure follow-up type servovalve of the present invention.
In the present embodiment, pressure follow-up type servovalve comprises housing 50, is positioned at the spool 5 of housing 50 and the first decompression half-bridge 30.
Wherein, spool 5 is asymmetric plunger, comprises the post portion 51 of stretching out outside housing 50 and is connected with post portion 51 and is positioned at the piston part of housing 50.
Piston part has peripheral groove, and piston part is divided into the first cock body 52 and the second cock body 53 by peripheral groove.First cock body 52 and the second cock body 53 form Spielpassung with housing 50.
Housing 50 is divided into the rod chamber comprising post portion 51 by spool 5, the intermediate cavity between the first cock body 52 and the second cock body 53, and rodless cavity.
Housing 5 is provided with the first entrance 54, second entrance 55 and the 3rd entrance 56.
First entrance 54 is for receiving external hydraulic input, and the second entrance 55 is connected with external fuel tank T.So, pressure follow-up type servovalve of the present invention by the second entrance 55 externally fuel tank T discharge unnecessary oil.
First entrance 54 is also connected with the first first end reducing pressure half-bridge 30, and also reduce pressure with first second end of half-bridge 30 of the second entrance 55 is connected, and the 3rd entrance 56 is connected with the first middle end reducing pressure half-bridge 30, after external hydraulic is inputted dividing potential drop, input to rodless cavity.
Housing 50 is also provided with outlet 57 and feedback port 58, feedback port 58 for by outlet 57 hydraulic feedback to rod chamber.
In one embodiment, the first decompression half-bridge 30 can comprise first segment discharge orifice 3 and the second section discharge orifice 4 of series connection.First entrance 54 can be connected to the first end of first segment discharge orifice 3, and the 3rd entrance 56 can be connected to the second end of first segment discharge orifice 3 and the first end of second section discharge orifice 4.Second entrance 55 is connected to the second end of second section discharge orifice 4.In other words, because the second entrance 55 is connected with external fuel tank T with second section discharge orifice 4 simultaneously, the oil pressure of the second end of the second entrance 55 and second section discharge orifice 4 is zero.
In another embodiment, pressure follow-up type servovalve can also comprise the second decompression half-bridge 70.
Second decompression half-bridge 70 can comprise the 3rd throttle orifice 7 and the 4th throttle orifice 8 of series connection.The first end of the 3rd throttle orifice 7 can be connected with outlet 57.Second end of the 3rd throttle orifice 7 is connected with feedback port 58 with the first end of the 4th throttle orifice 8.Second end of the 4th throttle orifice 8 is connected with external fuel tank T, makes the oil pressure of the second end of the 4th throttle orifice 8 be zero.
Pressure follow-up type servovalve also comprises power plant 1.Power plant 1 for apply to post portion 51 along poppet shaft to axial force, based on axial force regulate outlet output hydraulic pressure.
In one embodiment, power plant 1 can be such as proportion electro-magnet or voice coil motor etc.
As a kind of preferred version, pressure follow-up type servovalve can also comprise the first spring 2 be arranged in rod chamber and the second spring 6 be arranged in rodless cavity.First spring 2 and the elastic force direction of the second spring 6 and the dead in line of spool, and the first spring 2 and the second spring 6 work in unstretched condition.
If the thrust of power plant 1 is F
m, making a concerted effort for F of the first spring 2 and the second spring 6
k.When ignoring hydraulic power, have during homeostasis:
F
M-F
K＝P
s’S
1-P
A’S
2＝P
sS
1/K
1-P
AS
2/K
2，
Wherein, S
1and S
2be respectively P
s' and P
a' active area, namely S1 is the sectional area of the second cock body 53 in rodless cavity, S
2for the sectional area of the first cock body 52 in rod chamber and the difference of post portion 51 sectional area, K
1be the decompression ratio of the first half-bridge 30, K
2it is the decompression ratio of the second half-bridge 70.
Because spool travel is very little, therefore spring force also can be ignored, if there is S
1/ K
1=S
2/ K
2then have during homeostasis:
F
M＝P
sS
1/K
1-P
AS
2/K
2＝(P
s-P
A)S
1/K
1＝(P
s-P
A)S
2/K
2
As the thrust F of power plant 1
mafter setting, just can approximation control inlet outlet pressure differential P
s-P
a, and then control valve outlet oil pressure P
a.
As a kind of preferred version, because the active area at spool 5 two ends is asymmetric, cause inlet outlet pressure differential P
s-P
awith the thrust F of power plant 1
mdisproportionate, increase and control difficulty.For making up this asymmetric power, the difference of decompression ratio of can be reduced pressure by setting first half-bridge 30 and the second decompression half-bridge 70, makes P
sand P
atime equal, there is S
1/ K
1=S
2/ K
2, then P can be made
s-P
awith power plant thrust F
mproportional.
Because the first decompression half-bridge 30 reduces the oil pressure inputed in housing, power plant 1 can be made by a less ouput force only can to control the oil pressure P of outlet 57
ait is a predefined value.Therefore, the volume of whole pressure follow-up type servovalve can be reduced.
Fig. 3 is the pressure follow-up type servovalve spool of Fig. 2 schematic diagram when being positioned at right position, and Fig. 4 is the pressure follow-up type servovalve spool of Fig. 2 schematic diagram when being positioned at left position.
Below in conjunction with Fig. 2-4, the working state of the pressure follow-up type servovalve of present embodiment is described.
When pressure follow-up type servovalve is just started working, its spool is in meta, as the valve element position in Fig. 2.
As needs output oil pressure P
awhen being a predetermined value, the thrust output of power plant 1 should be regulated.
Suppose at thrust F
mwith the F that makes a concerted effort of the first spring 2 and the second spring 6
kunder effect, spool 5 moves to right position (as shown in Figure 3), now exports 57 and leads to external fuel tank T-phase, the oil pressure P of outlet 57
ato reduce, meanwhile, the oil pressure P of feedback port 58
a' also reduce, the power caused acting in rod chamber on the first cock body 52 to the right reduces, and spool is moved to the left.
When spool is pushed to left position as shown in Figure 3, outlet 57 communicates with the first entrance 54, exports 57 oil pressure P
ato increase, meanwhile, the oil pressure P of feedback port 58
a' also increase, the power caused acting in rod chamber on the first cock body 52 to the right increases, and spool 5 moves right.
By above-mentioned adjustment process, final spool 5 will be stabilized in and make outlet oil pressure P
aequal the position of predefined value.
Being described as can be seen from above, by setting the thrust of power plant 1, just can control the oil pressure P of import and export 57
a.If the oil pressure P of outlet 57
ahigher than setting value, spool 5 moves right, the oil pressure P of outlet 57
areduce, until keep balance.Similarly, if the oil pressure P of outlet 57
alower than setting value, spool 5 is moved to the left, the oil pressure P of outlet 57
aincrease, until keep balance.
Pressure follow-up type servovalve of the present invention, small volume, can obtain one less, become the outlet oil pressure of some linear with entrance oil pressure.
Above some embodiments of the present invention are described in detail.As one of ordinary skill in the art can be understood, whole or any step of method and apparatus of the present invention or parts, can in the network of any calculating equipment (comprising processor, storage medium etc.) or calculating equipment, realized with hardware, firmware, software or their combination, this is that those of ordinary skill in the art use their basic programming skill just can realize when understanding content of the present invention, therefore need not illustrate at this.
In addition, it is evident that, when relating to possible peripheral operation in superincumbent explanation, any display device and any input device, corresponding interface and control program that are connected to any calculating equipment will be used undoubtedly.Generally speaking, related hardware in computer, computer system or computer network, software and realize the hardware of the various operations in preceding method of the present invention, firmware, software or their combination, namely form equipment of the present invention and each constituent elements thereof.
Therefore, based on above-mentioned understanding, object of the present invention can also be realized by an operation program or batch processing on any messaging device.Described messaging device can be known standard equipment.Therefore, object of the present invention also can realize only by the program product of providing package containing the program-code realizing described method or equipment.That is, such program product also forms the present invention, and stores or the medium that transmits such program product also forms the present invention.Obviously, described storage or transmission medium can be well known by persons skilled in the art, or the storage of any type developed in the future or transmission medium, therefore also there is no need to enumerate various storage or transmission medium at this.
In equipment of the present invention and method, obviously, each parts or each step reconfigure after can decomposing, combine and/or decomposing.These decompose and/or reconfigure and should be considered as equivalents of the present invention.Also it is pointed out that the step performing above-mentioned series of processes can order naturally following the instructions perform in chronological order, but do not need necessarily to perform according to time sequencing.Some step can walk abreast or perform independently of one another.Simultaneously, above in the description of the specific embodiment of the invention, the feature described for a kind of mode of execution and/or illustrate can use in one or more other mode of execution in same or similar mode, combined with the feature in other mode of execution, or substitute the feature in other mode of execution.
Should emphasize, term " comprises/comprises " existence referring to feature, key element, step or assembly when using herein, but does not get rid of the existence or additional of one or more further feature, key element, step or assembly.
Although described the present invention and advantage thereof in detail, be to be understood that and can have carried out various change when not exceeding the spirit and scope of the present invention limited by appended claim, substituting and conversion.And the scope of the application is not limited only to the specific embodiment of process, equipment, means, method and step described by specification.One of ordinary skilled in the art will readily appreciate that from disclosure of the present invention, can use perform the function substantially identical with corresponding embodiment described herein or obtain and its substantially identical result, existing and that will be developed in the future process, equipment, means, method or step according to the present invention.Therefore, appended claim is intended to comprise such process, equipment, means, method or step in their scope.
Claims (6)
1. a pressure follow-up type servovalve, comprises housing and the spool being positioned at housing, it is characterized in that, also comprise the first decompression half-bridge;
Wherein,
Described spool is asymmetric plunger, comprise the post portion of stretching out outside described housing and be connected with described post portion and be positioned at the piston part of described housing, described piston part has peripheral groove, described piston part is divided into the first cock body and the second cock body by described peripheral groove, and described first cock body and described second cock body and described housing form Spielpassung;
Described housing is divided into the rod chamber including described post portion by described spool, the intermediate cavity between described first cock body and described second cock body, and rodless cavity;
Described housing is provided with the first entrance, the second entrance and the 3rd entrance;
Described first entrance is for receiving external hydraulic input, and described second entrance is connected with external fuel tank;
Described first entrance is also connected with the described first first end reducing pressure half-bridge, also reduce pressure with described first second end of half-bridge of described second entrance is connected, described 3rd entrance is connected with the described first middle end reducing pressure half-bridge, for inputing to described rodless cavity by after described external hydraulic input dividing potential drop;
Described housing is also provided with outlet and feedback port, described feedback port is used for described outlet hydraulic to feed back to described rod chamber.
2. pressure follow-up type servovalve according to claim 1, is characterized in that:
Described first decompression half-bridge comprises first segment discharge orifice and the second section discharge orifice of series connection;
Described first entrance is connected to the first end of described first segment discharge orifice;
Described 3rd entrance is connected to the second end of described first segment discharge orifice and the first end of described second section discharge orifice;
Described second entrance is connected to the second end of described second section discharge orifice.
3. pressure follow-up type servovalve according to claim 1, is characterized in that:
Also comprise the second decompression half-bridge;
Described second decompression half-bridge comprises the 3rd throttle orifice and the 4th throttle orifice of series connection;
The first end of described 3rd throttle orifice is connected with described outlet;
Second end of described 3rd throttle orifice is connected with described feedback port with the first end of described 4th throttle orifice;
Second end of described 4th throttle orifice is connected with described external fuel tank.
4. the pressure follow-up type servovalve according to claim 1-3 any one, is characterized in that, also comprise power plant;
Described power plant be used for applying to described post portion along described poppet shaft to axial force, regulate the output hydraulic pressure of described outlet based on described axial force.
5. pressure follow-up type servovalve according to claim 4, is characterized in that:
Described power plant are proportion electro-magnet or voice coil motor.
6. the pressure follow-up type servovalve according to claim, is characterized in that, also comprise:
The second spring being arranged at the first spring in described rod chamber and being arranged in described rodless cavity;
The elastic force direction of described first spring and described second spring and the dead in line of described spool, and described first spring and described second spring works are in unstretched condition.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510119642.8A CN104819178B (en) | 2015-03-18 | 2015-03-18 | pressure follow-up servo valve |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510119642.8A CN104819178B (en) | 2015-03-18 | 2015-03-18 | pressure follow-up servo valve |
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| Publication Number | Publication Date |
|---|---|
| CN104819178A true CN104819178A (en) | 2015-08-05 |
| CN104819178B CN104819178B (en) | 2017-04-12 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510119642.8A Active CN104819178B (en) | 2015-03-18 | 2015-03-18 | pressure follow-up servo valve |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105156737A (en) * | 2015-09-18 | 2015-12-16 | 南京工程学院 | Voice-coil-motor-driven pilot servo valve control system and control method |
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| CN101806314A (en) * | 2010-04-09 | 2010-08-18 | 北京航空航天大学 | Hydraulic spiral half-bridge pilot structure |
| CN102878139A (en) * | 2012-10-24 | 2013-01-16 | 哈尔滨工业大学 | Piezoelectric-liquid-actuated elastic-membrane-position electric feedback two-stage servo valve and control method thereof |
| CN103256401A (en) * | 2013-04-27 | 2013-08-21 | 浙江工业大学 | Prestretching-pretwisting type full-bridge 2D electro-hydraulic proportional directional valve |
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2015
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Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2157347Y (en) * | 1993-03-31 | 1994-02-23 | 付重庆 | Speed control valve set |
| CN1131289A (en) * | 1995-12-06 | 1996-09-18 | 华中理工大学 | PWM proportional control method |
| JP3673118B2 (en) * | 1999-06-22 | 2005-07-20 | 新キャタピラー三菱株式会社 | Control device for fluid pressure actuator |
| CN1337539A (en) * | 2001-09-05 | 2002-02-27 | 宁波华液机器制造有限公司 | Pressure difference feedback type precontrolled slide valve |
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| CN102878139A (en) * | 2012-10-24 | 2013-01-16 | 哈尔滨工业大学 | Piezoelectric-liquid-actuated elastic-membrane-position electric feedback two-stage servo valve and control method thereof |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105156737A (en) * | 2015-09-18 | 2015-12-16 | 南京工程学院 | Voice-coil-motor-driven pilot servo valve control system and control method |
| CN105156737B (en) * | 2015-09-18 | 2018-02-13 | 南京工程学院 | A kind of the pilot type servo valve control system and its control method of voice coil motor driving |
Also Published As
| Publication number | Publication date |
|---|---|
| CN104819178B (en) | 2017-04-12 |
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