CN103821787B - Pressure is adopted to turn round the hydraulic pilot individual loads multi-way valve of two-dimentional spring - Google Patents
Pressure is adopted to turn round the hydraulic pilot individual loads multi-way valve of two-dimentional spring Download PDFInfo
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- CN103821787B CN103821787B CN201410088238.4A CN201410088238A CN103821787B CN 103821787 B CN103821787 B CN 103821787B CN 201410088238 A CN201410088238 A CN 201410088238A CN 103821787 B CN103821787 B CN 103821787B
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Abstract
The invention provides a kind of hydraulic pilot individual loads multi-way valve adopting pressure to turn round two-dimentional spring, comprise multiple individual loads valve, described individual loads valve comprises valve body, two valve pockets are provided with in described valve body, described valve body is provided with oil-feed port and return opening, described oil-feed port is communicated with described valve pocket respectively with described return opening, each described valve pocket is all communicated with control port, spool is provided with in each described valve pocket, one end of described spool connects hydraulic pressure guide structure, the other end connects pressure and turns round two-dimentional spring, the described oil-feed port of each described individual loads valve is connected respectively with described return opening.Such scheme provided by the invention, adopts hydraulic pilot structure as pilot stage, reduces cost, improve performance.By pressure turn round two-dimentional spring have spool axial displacement and rotate between conversion function, achieve to pilot stage rotate mechanical reverse feedback.
Description
Technical field
The present invention relates to hydraulic and pneumatic field, particularly relate to a kind of hydraulic pilot individual loads multi-way valve adopting pressure to turn round two-dimentional spring.
Background technique
In engineering machinery hydraulic and pneumatic field, multi-way valve is the critical component of Hydraulics and pneumatics control technique, due to the reason such as complexity and increase system efficiency of load behavior, individual loads multi-way valve becomes the study hotspot of engineering machinery field, it by traditional three position four-way directional control valve two load ports separately independently controls flow and pressure separately, relieves coupling between the two, current individual loads multi-way valve is still at an early stage of development, and correlation technique is still immature.
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.
The invention provides a kind of hydraulic pilot individual loads multi-way valve adopting pressure to turn round two-dimentional spring, in order to solve the deficiency of existing individual loads multi-way valve, accelerate individual loads multi-way valve industrialization paces.
The invention provides a kind of hydraulic pilot individual loads multi-way valve adopting pressure to turn round two-dimentional spring, comprise multiple individual loads valve, described individual loads valve comprises valve body, two valve pockets are provided with in described valve body, described valve body is provided with oil-feed port and return opening, described oil-feed port is communicated with described valve pocket respectively with described return opening, each described valve pocket is all communicated with control port, spool is provided with in each described valve pocket, one end of described spool connects hydraulic pressure guide structure, the other end connects pressure and turns round two-dimentional spring, the described oil-feed port of each described individual loads valve is connected respectively with described return opening.
Such scheme provided by the invention, adopts hydraulic pilot structure as pilot stage, reduces cost, improve performance.By pressure turn round two-dimentional spring achieve spool axial displacement and rotate between conversion, achieve to pilot stage rotate mechanical reverse feedback.And it has broken the necessary consistent coupling of import and export orifice size by double spool control technique, make system have two degrees of freedom, independent control flow and pressure, can adapt to different loads and operating mode well separately, allow motion become quick and stable more, improve system effectiveness.
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 turns round the stereogram of the hydraulic pilot individual loads multi-way valve of two-dimentional spring for employing pressure that the embodiment of the present invention provides;
Fig. 2 turns round the sectional view of the hydraulic pilot individual loads multi-way valve of two-dimentional spring for employing pressure that the embodiment of the present invention provides;
The schematic diagram of the hydraulic pilot structure that Fig. 3 provides for the embodiment of the present invention;
The schematic diagram of another hydraulic pilot structure that Fig. 4 provides for the embodiment of the present invention;
Fig. 5 turns round the stereogram at two-dimentional spring position for pressure that inventive embodiments provides.
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.
Fig. 1 turns round the stereogram of the hydraulic pilot individual loads multi-way valve of two-dimentional spring for employing pressure that the embodiment of the present invention provides; Fig. 2 turns round the sectional view of the hydraulic pilot individual loads multi-way valve of two-dimentional spring for employing pressure that the embodiment of the present invention provides.As Fig. 1, shown in Fig. 2, the employing pressure that the embodiment of the present invention provides turns round the hydraulic pilot individual loads multi-way valve of two-dimentional spring, comprise multiple individual loads valve, individual loads valve comprises valve body 11, two valve pockets are provided with in valve body 11, valve body 11 is provided with oil-feed port 10 and return opening 8, oil-feed port 10 is communicated with valve pocket respectively with return opening 8, the valve pocket on top is communicated with control port 6, the valve pocket of bottom is communicated with control port 9, spool 4 is provided with in each valve pocket, one end of spool 4 connects hydraulic pressure guide structure 3, the other end connects pressure and turns round two-dimentional spring 7, the oil-feed port 10 of each individual loads valve is connected respectively with return opening 8.
Such scheme provided by the invention, adopt hydraulic pilot structure as pilot stage, hydraulic pilot magnification factor is large, and structure is simple, reduces cost, improves performance, accelerate individual loads multi-way valve industrialization paces.By pressure turn round two-dimentional spring 7 achieve spool axial displacement and rotate between conversion, achieve to pilot stage rotate mechanical reverse feedback.
In actual use, the valve body of multiple individual loads valve can be separate, also can be integral structure.In the embodiment of the present invention, the hydraulic pilot individual loads multi-way valve adopting pressure to turn round two-dimentional spring illustrated in fig. 1 is three-way valve, and be also namely made up of three individual loads valves, its valve body is integral type structure.Certainly, according to concrete service condition, also can be not limited to adopt three-way valve, the quantity of individual loads valve can be selected arbitrarily to form corresponding multi-way valve, only need ensure that the oil-feed port 10 of each individual loads valve is interconnected, each return opening 8 is interconnected, and also namely the oil-feed port 10 of each individual loads valve is connected respectively with return opening 8.
As shown in Figure 3, hydraulic pilot structure comprises the guide's valve pocket 302 be fixedly connected with spool, pilot valve 301 is provided with in guide's valve pocket 302, the axis of pilot valve 301 is consistent with the axial direction of spool, the sidewall of pilot valve 301 is provided with two straight-line grooves 304, guide's valve pocket 302 is provided with two groups of oil throughs that can be communicated with straight-line groove 304.The sidewall of pilot valve arranges straight-line groove 304 and is convenient to processing, and the conformity that in different pilot valve 301, straight-line groove 304 is processed can be improved.The hydraulic pilot mechanism of said structure, control pilot valve 301 by rotation driving parts such as electric rotating machines to rotate, straight-line groove 304 in pilot valve 301 is crossing with group oil through of two on guide's valve pocket 302 respectively little bow-shaped area, form two groups of variable orifices 303 [1], 303 [2], two variable orifices of each group and the charge oil pressure end of spool form hydraulic damping half-bridge structure, the rotation of pilot valve 301 causes hydraulic damping half-bridge disequilibrium, just on the visual angle of Fig. 3, when the angle of swing of pilot valve 301 is clockwise, the area being positioned at the variable orifice 303 [1] of upside becomes large, the area being positioned at the variable orifice 303 [1] of downside diminishes, the oil liquid pressure of the responsive oil circuit 305 of guide is diminished, the oil liquid pressure keeping system charge oil pressure of the spool the other end is constant, this just promotes whole spool and moves to the left.Owing to adopting above-mentioned hydraulic pilot structure to form hydraulic damping half-bridge structure, make this employing pressure turn round the hydraulic pilot individual loads multi-way valve structure of two-dimentional spring simply, contamination resistance is strong, and hydraulic pilot magnification factor is large, and dynamic response is fast.Guide's valve pocket and spool one are processed herein, can think that guide's valve pocket is a part for spool.
As shown in Figure 4, hydraulic pilot structure can also be following structure, the guide's valve pocket 302 comprising sleeve 306 and be fixedly connected with spool, guide's valve pocket 302 is arranged in sleeve 306, pilot valve 301 is provided with in guide's valve pocket 302, the axis of pilot valve 301 is consistent with the axial direction of spool, the sidewall of pilot valve 301 is provided with two straight-line grooves 304, guide's valve pocket 302 is provided with two groups of oil throughs that can be communicated with straight-line groove 304, sleeve 306 is provided with two fixing damping orifices 307, two fixing damping orifices 307 are communicated with oil through described in two groups respectively.The hydraulic pilot mechanism of this structure, rotate by controlling pilot valve 301, straight-line groove 304 in pilot valve 301 is crossing with group oil through of two on guide's valve pocket 302 respectively little bow-shaped area, form variable orifice 303 [1], 303 [2], two variable orifice and two the fixing damping orifices 307 be positioned on sleeve 306 of each group form hydraulic damping full bridge structure, the rotation of pilot valve 301 causes hydraulic damping full-bridge disequilibrium, just under the visual angle of Fig. 4, when the angle of swing of pilot valve is clockwise, the area being positioned at the variable orifice 303 [1] in left side becomes large, the area being positioned at the variable orifice 303 [1] on right side diminishes, the pressure on the right side of spool is made to be greater than the pressure in left side, promotion spool moves by the left.Owing to adopting above-mentioned hydraulic pilot structure to form hydraulic damping full bridge structure, make this employing pressure turn round the hydraulic pilot individual loads multi-way valve structure of two-dimentional spring simply, contamination resistance is strong, and hydraulic pilot magnification factor is large, and dynamic response is fast.
In actual use, see also Fig. 3 or Fig. 4, pilot valve 301 is circumferentially provided with two straight-line grooves 304 and two groups of oil throughs, often organize oil through and there are two circumferentially angled holes, in order to increase control ratio coefficient and improve Security, can also circumferentially multiple straight-line groove and organize oil through more, pilot stage has redundancy, can ensure that this hydraulic pilot structure can continue normal work when some pilot stage breaks down.
Valve body generally installs an electric rotating machine 1(see Fig. 2 by Motor connecting device 2), electric rotating machine 1 is for example and without limitation to voice coil motor, stepper motor etc.Namely electric rotating machine 1 is connected with pilot valve 3, controls pilot valve 3 and rotates, and also electric rotating machine 1 drives with pilot valve 3 and is connected.In order to improve speed of response and system effectiveness, strengthen control performance, control port is provided with pressure transducer 5.Send control signal by controller to control corresponding electric rotating machine 1 and rotate, electric rotating machine 1 output shaft drives pilot valve 3 to rotate, break the balance of hydraulic damping half-bridge or full bridge structure, thus promote the motion of spool 4, in addition, controller is by realizing the control to spool travel to the Angle ambiguity of electric rotating machine, simultaneously by the pressure signal of pressure transducer 5 Real-time Collection oil circuit control, the uninterrupted of two oil circuit controls in each road is obtained again by throttling formula, so then can carry out independently flow according to the load behavior of engineering machinery, pressure closed loop controls, therefore the speed of response has been speeded, improve system effectiveness.This scheme has broken the necessary consistent coupling of import and export orifice size, makes system have two degrees of freedom, and independent control flow and pressure, can well adapt to different loads and operating mode, allow motion become quick and stable more, improve the efficiency of system separately.
As shown in Figure 5, turn round two-dimentional spring 7 to prevent pressure to rotate, end cap 12 is fixedly connected with in one end of valve pocket, pressure is turned round two-dimentional spring 7 and is press-fited between spool 4 and end cap 12, pressure is turned round on two-dimentional spring 7 and is provided with fixed block 701, end cap 12 is provided with draw-in groove 1201, fixed block 701 and draw-in groove 1201 fix snap-fit engagement.
Wherein, pressure turns round the spirality spring sheet that two-dimentional spring 7 comprises fixed block and is connected with fixed block.As shown in Figure 5, as a kind of optimal way, pressure is turned round two-dimentional spring 7 and is comprised two fixed blocks coaxially arranged, symmetrical spirality spring sheet is installed with between two fixed blocks, certainly, the structure that pressure turns round two-dimentional spring 7 can be not limited only to said structure, as long as it has corresponding windup-degree when axially loaded moves.
Pressure is turned round two-dimentional spring 7 and is had certain axial precompression when mounted, effectively can prevent spool 4 from rotating like this and bring adverse influence to hydraulic pilot structure.In addition, pressure is turned round two-dimentional spring 7 and is had displacement mechanical negative feedback, when pilot valve rotary actuation spool towards compression pressure turn round two-dimentional spring 7 move time, pressure turns round two-dimentional spring 7 can be subject to axial pressure generation compression, simultaneously because component radially can produce a little windup-degree, wherein, the ratio of this windup-degree and axial displacement is determined by design parameter, this just makes the area of two of hydraulic pilot structure variable orifices move towards identical direction, hydraulic damping half-bridge or full bridge structure tend to balance, spool 4 two ends pressure reduction reduces, spool 4 moves towards equilibrium position, play the degenerative effect of displacement mechanical.
See also Fig. 1, the employing pressure of this programme turns round the hydraulic pilot individual loads multi-way valve of two-dimentional spring in use, and the pilot valve of two hydraulic pilot structures of each road individual loads valve, rotates respectively under the drive of electric rotating machine.Thus two control ports are carried out to the independence control of flow and pressure, realize commutation function.When upside spool 3 moves towards motion downside, left side spool 3 towards right side, oil-feed port 10 is connected with the high voltage control hydraulic fluid port 6 of upside, return opening 8 is connected with the low voltage control hydraulic fluid port 9 of downside, fluid flows into the control port 6 of upside from oil-feed port 10, after over power, fluid flows to return opening 8 from the control port 9 of downside, when upside spool 3 moves towards motion downside, right side spool 3 towards left side, oil-feed port 10 is connected with the high voltage control hydraulic fluid port 9 of downside, return opening 8 is connected with the low voltage control hydraulic fluid port 6 of upside, fluid flows into the control port 9 of downside from oil-feed port 10, after over power, fluid flows to return opening 8 from the control port 6 of upside, form complete circulating oil path.
Last it is noted that above embodiment is only in order to illustrate technological scheme of the present invention, be not intended to limit; Although with reference to previous embodiment to invention has been detailed description, those of ordinary skill in the art is to be understood that: it still can be modified to the technological scheme described in foregoing embodiments, or carries out equivalent replacement to wherein portion of techniques feature; And these amendments or replacement, do not make the essence of appropriate technical solution depart from the spirit and scope of various embodiments of the present invention technological scheme.
Claims (9)
1. the hydraulic pilot individual loads multi-way valve adopting pressure to turn round two-dimentional spring, comprise multiple individual loads valve, it is characterized in that, described individual loads valve comprises valve body, two valve pockets are provided with in described valve body, described valve body is provided with oil-feed port and return opening, described oil-feed port is communicated with described valve pocket respectively with described return opening, each described valve pocket is all communicated with control port, main valve plug is provided with in each described valve pocket, one end of described main valve plug connects hydraulic pressure guide structure, the other end connects pressure and turns round two-dimentional spring, the described oil-feed port of each described individual loads valve is connected respectively with described return opening,
Described hydraulic pilot structure comprises the guide's valve pocket be fixedly connected with described main valve plug, pilot valve is provided with in described guide's valve pocket, the axis of described pilot valve is consistent with the axial direction of described main valve plug, the sidewall of described pilot valve is provided with straight-line groove, and described pilot valve puts the oil through being provided with and can being communicated with described straight-line groove.
2. the hydraulic pilot individual loads multi-way valve adopting pressure to turn round two-dimentional spring according to claim 1, it is characterized in that, guide's valve pocket that described hydraulic pilot structure comprises sleeve and is fixedly connected with described main valve plug, described pilot valve cover is arranged in described sleeve, pilot valve is provided with in described guide's valve pocket, the axis of described pilot valve is consistent with the axial direction of described main valve plug, the sidewall of described pilot valve is provided with straight-line groove, described pilot valve puts the oil through being provided with and can being communicated with described straight-line groove, described sleeve is provided with two fixing damping orifices, two described fixing damping orifices are communicated with described oil through respectively.
3. the hydraulic pilot individual loads multi-way valve adopting pressure to turn round two-dimentional spring according to claim 1 and 2, it is characterized in that, described pilot valve is provided with described straight-line groove, multiple described straight-line grooves circumferentially setting gradually in described pilot valve, described pilot valve puts the oil through that Xiang Yingyou many groups sets gradually.
4. the hydraulic pilot individual loads multi-way valve adopting pressure to turn round two-dimentional spring according to claim 1 and 2, it is characterized in that, described control port is provided with pressure transducer.
5. the hydraulic pilot individual loads multi-way valve adopting pressure to turn round two-dimentional spring according to claim 1 and 2, it is characterized in that, the displacement of described main valve plug and the corner of described pilot valve proportional, adopt electric rotating machine to carry out Angle ambiguity to described pilot valve and reach control to main valve plug displacement.
6. the hydraulic pilot individual loads multi-way valve adopting pressure to turn round two-dimentional spring according to claim 1 and 2, it is characterized in that, one end of described valve pocket is fixedly connected with end cap, described pressure turns round two-dimentional pressure mounting of the spring between described main valve plug and described end cap, described pressure is turned round on two-dimentional spring and is provided with fixed block, described end cap is provided with draw-in groove, and described fixed block and described draw-in groove fix snap-fit engagement, described pressure turn round two-dimentional spring achieve main valve plug straight line motion and rotate between conversion.
7. the hydraulic pilot individual loads multi-way valve adopting pressure to turn round two-dimentional spring according to claim 1 and 2, it is characterized in that, described main valve plug and described guide's valve pocket are structure as a whole.
8. the hydraulic pilot individual loads multi-way valve adopting pressure to turn round two-dimentional spring according to claim 1 and 2, is characterized in that, described pressure is turned round two-dimentional spring and comprised two fixed blocks coaxially arranged, and is fixedly installed spirality spring sheet between two fixed blocks.
9. the hydraulic pilot individual loads multi-way valve adopting pressure to turn round two-dimentional spring according to claim 1 and 2, it is characterized in that, described valve body is fixedly connected with electric rotating machine by Motor connecting device, described electric rotating machine drives with described pilot valve and is connected.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201410088238.4A CN103821787B (en) | 2014-03-11 | 2014-03-11 | Pressure is adopted to turn round the hydraulic pilot individual loads multi-way valve of two-dimentional spring |
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| CN201410088238.4A CN103821787B (en) | 2014-03-11 | 2014-03-11 | Pressure is adopted to turn round the hydraulic pilot individual loads multi-way valve of two-dimentional spring |
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| CN103821787B true CN103821787B (en) | 2016-04-06 |
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| CN105090149B (en) * | 2015-06-12 | 2017-04-12 | 北京航空航天大学 | Positive-feedback electro-hydraulic high-speed two-way switching valve |
| CN112728166A (en) * | 2021-01-04 | 2021-04-30 | 江苏恒立液压科技有限公司 | Hydraulic multi-way valve with independently controlled oil ports and control method thereof |
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| US6554014B2 (en) * | 2000-10-13 | 2003-04-29 | Hydraforce, Inc. | Proportional pilot operated directional valve |
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| CN101457633A (en) * | 2008-12-25 | 2009-06-17 | 浙江大学 | Independence control hydraulic impactor for piston displacement electric feedback load port |
| CN102459921A (en) * | 2009-06-02 | 2012-05-16 | 伊顿公司 | Two position three way valve |
| CN102913496A (en) * | 2012-10-24 | 2013-02-06 | 浙江工业大学 | Bi-directional full-bridge 2D electro-hydraulic proportional directional valve |
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