CN203627917U - Pretensioning-pretwisting type full bridge 2D electric-hydraulic proportional reversing valve - Google Patents
Pretensioning-pretwisting type full bridge 2D electric-hydraulic proportional reversing valve Download PDFInfo
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- CN203627917U CN203627917U CN201320229517.9U CN201320229517U CN203627917U CN 203627917 U CN203627917 U CN 203627917U CN 201320229517 U CN201320229517 U CN 201320229517U CN 203627917 U CN203627917 U CN 203627917U
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Abstract
Disclosed is a pretensioning-pretwisting type full bridge 2D electric-hydraulic proportional reversing valve. The two ends of the 2D valve are connected to an electric-mechanical converter through a pressure-torsion coupler and a spring. The spring (4) is disposed between a valve body and a sliding wedge. The pre-compression amount of the spring is slightly greater than the valve core stroke. End circular beads, the sliding wedge and the valve body form a left sensitive chamber and a right sensitive chamber. The end circular beads are provided with a pair of high pressure holes (a and b) and a pair of low pressure holes (e and d) that are respectively communicated with a P port and a T port through a valve core inner hole. Two ends of the inner hole wall of the valve body are respectively provided with feeling channels (c and f) that are respectively communicated with the left and the right sensitive chambers (g and h). The high pressure holes and the low pressure holes of the end circular beads are intersected with the feeling channels to each form two minisize opening areas that are in series connection to form hydraulic resistance semi-bridges. The pressure of the sensitive chambers at the two ends is respectively controlled by the hydraulic resistance semi-bridges at two ends.
Description
Technical field
The utility model belongs to the electro-hydraulic proportional valve in Fluid-transmission and control field, relates in particular to a kind of electro-hydraulic proportion reversing valve.
Background technique
Electro-hydraulic servo control technology has organically combined the advantage of Fluid-transmission control technique and information electronic technology, is applied, and rakes in successfully at important national strategy army industrial fields such as Aero-Space, sophisticated weapons, iron and steel, power generations.But it is poor that electrohydraulic control also exists contamination resistance simultaneously, valve internal pressure loss large (7MPa), manufacture cost and maintenance cost are high, and system energy consumption loses the defects such as large.Because many defects that electrohydraulic control exists can cannot be widely used its fast-response having in general industry equipment.Simultaneously traditional electrohydraulic valve control can not meet modern industry again produces the requirement of needed high quality control system.Therefore, people wish a kind of production and maintenance cost is low, safe and reliable, control accuracy and response characteristic all can meet industrial control system actual demand electrohydraulic control technology.
For these reasons, people have proposed electrohydraulic proportion technology.As the representative of electrohydraulic proportion technology, electro-hydraulic proportional valve is to use on the basis of hydrovalve in traditional industry, adopts reliable inexpensive electromechanical converter (proportion electro-magnet etc.) and valve correspondingly to design.Thereby obtain, oil is required to proportional control element identical with general industry valve, that valve internal pressure loss is few, performance can meet again most of industrial control requirement.
Because electro-hydraulic proportional valve can be combined with electric control device, can carry out computing and processing to various inputs, output signal very easily, realize complicated control function.It has again antipollution, low cost and responds advantage faster simultaneously.In industrial production, obtain a wide range of applications, as ceramic floor brick pressure machine, the permanent tension force control of band steel, pressurized container fatigue life test machine, hudraulic lift motion and control system, the control of metal-cutting machine tool working table movement, rolling mill pressure and the control system of rolling with steel, Presseshydraulic, tube bender, plastic injection machine etc.
In ratio control system, electro-hydraulic proportional valve is electro-hydraulic conversion element, is also power amplification element simultaneously.It plays an important role to the performance of system, is the core parts of ratio control system.
The most significant feature of electro-hydraulic proportional valve and the most successful part are that adoption rate electromagnet is as electromechanical converter.Compare with moving-iron type torque motor with moving coil, that proportion electro-magnet has is simple and reliable for structure, good manufacturability, can export the advantages such as larger power and displacement and working service is convenient.Proportion electro-magnet, except as driving pilot valve, also can be used as directly driving low power output stage.Such as, balance each other and control the direct action type proportional valve of valve element position principle according to electromagnet thrust and spring force, be only applicable to small flow occasion, the maximum functional flow of practical application is generally 21MPa at 15L/min(maximum service pressure) below.In addition, press equilibrium of forces in order to realize axial static, direct action type proportional selector valve or Flow valve all adopt sliding valve structure, and " clamping stagnation " phenomenon appears in the impact that is easily subject to frictional force and oil contamination.
Adopt Linear displacement transducer (LVDT) to measure and closed loop control valve element position, form directly moving proportional reversing valve of electric feedback-type, can improve to a great extent locating stiffness and the control accuracy of spool, simultaneously, people are also at its model, a large amount of theoretical research work has been carried out in non-linear and system applies aspect, finally make the straight moving Proportional valve of electricity feedback can as servovalve, be applied to the closed loop control of hydraulic system, but eventually because being subject to limitation of magnetic saturation, proportion electro-magnet ouput force is limited, cannot fundamentally solve high pressure, the problem that affects of hydraulic power under large flow, under the working state of high pressure (pressure reduction is large) and large flow, still there will be flow saturated phenomenon.
The conveyance capacity of eliminating hydraulic power impact, raising hydrovalve, the most basic way is to adopt control (pilot control) technology of leading.As far back as American engineer Harry Vickers in 1936 for solve because of the straight moving relief valve of hydraulic power impact cannot realize high pressure, Mass flow system pressure control problem model utility lead control relief valve, its basic thought is to adopt the less pilot valve control static pressure of a latus rectum, the motion of driving main valve plug, when valve port flow through because of this hydraulic thrust than fluid, institute's hydraulic power that produces is much bigger, is enough to eliminate it to main valve plug motion and the adverse effect of controlling generation.The thought of leading control was also widely used in the design of other hydrovalve afterwards, made hydraulic system high pressure, large flow control become reality.Various electro-hydraulic servo control elements are afterwards also the design philosophys of having continued to use pilot control, and electro-hydraulic proportional valve is no exception, and have used the many structural principles of servovalve.
Summary of the invention:
There is " clamping stagnation " phenomenon in order to overcome being subject to frictional force, hydraulic power and oil contamination impact of existing electro-hydraulic proportional valve and lead control level oil circuit decompression or pressure is too low makes whole valve cannot normally work and lead the larger deficiency of control level leakage flow, the utility model provides a kind of and not only has that the common control type of leading electro-hydraulic proportional valve flow is large, working pressure high, and under zero-pressure (decompression), also can as direct action type proportional valve, realize prestretching-pretwist type full-bridge type 2D electro-hydraulic proportion reversing valve of proportional control function.
Prestretching-pretwist type full-bridge type 2D electro-hydraulic proportion reversing valve described in the utility model, by the linear electromechanical converter at 2D valve, two ends, turn round coupling etc. in the pressure between them and form.2D valve is mainly made up of spool 9 and valve body 8, and spool has rotation and two freedom of movement (so gain the name " 2D valve ") that slide in valve body.(b, d and c, e), communicate with P mouth and T mouth respectively on the shoulder of spool two ends, respectively to offer a pair of high and low pressure hole; On valve body inner bore wall, two ends respectively offer one and experience passage (f
1, f
2and g
1, g
2), respectively with left and right sensitive cavity (h and j) communicate.When spool is installed in spool bore, the high and low pressure hole on the shoulder of spool two ends, with to experience passage crossing, forms two small opening areas, flowed friction half-bridge in series.The pressure of two ends sensitive cavity is controlled by respectively the flowed friction half-bridge at two ends.
It is the structure that the straight line motion of realizing linear electromechanical converter transfers the twist motion of spool to that described pressure is turned round coupling.In this process, can make full use of the feature of 2D valve hydraulic pressure Dao Kongqiao road Pressure gain large (small corner can make the pressure of sensitive cavity that larger variation occurs), by pressure being turned round to the appropriate design of coupling, to drive the torsional moment of valve core rotation to amplify, and make the adverse effect of the non-linear factor comparative example characteristics such as frictional force between spool and spool bore be reduced to minimum degree.
The electromagnetic push of linear electromechanical converter output is turned round coupling by pressure makes valve core rotation, and then the pressure that the makes valve sensitive cavity actuating valve core that changes moves axially, in mobile process, spool rotates backward, the pressure of its sensitive cavity reverts to again original value gradually, spool arrives a new equilibrium position, the displacement that spool moves and the proportional relation of the thrust of proportion electro-magnet.
The beneficial effects of the utility model are mainly manifested in: 1, for proportion electro-magnet because of magnetic saturation thrust output limited, propose to press and turned round amplification actuation techniques, proportion electro-magnet is amplified the driving force of spool, effectively eliminated the adverse effect that the non-linear factor comparative example characteristics such as frictional force between spool and spool bore cause; 2, realize and lead control type electric-hydraulic proportion commutation (throttling) valve function with the rotation of spool and two freedom of movement of slip, by valve core rotation, flowed friction bridge road delivery pressure is changed, and then generation static pressure actuating valve core axial motion, under high pressure, large flow, can effectively overcome the adverse effect that hydraulic power (Bernouilli force) causes, effectively improve axially locating (main valve opening) precision of spool; 3,2D commutation (throttling) valve, pressure are turned round to coupling and the coaxial connection of proportion electro-magnet three, form 2D electric-hydraulic proportion commutation (throttling) valve simple in structure, principle is advanced, not only have that the common control type of leading electro-hydraulic proportional valve flow is large, the high feature of working pressure, and under zero-pressure (decompression), also can as direct action type proportional valve, realize proportional control function.
Accompanying drawing explanation
Fig. 1 is the structural representation of prestretching-pretwist type full-bridge type 2D electro-hydraulic proportion reversing valve.
Fig. 2 is the spool valve body assembling schematic diagram of prestretching-pretwist type full-bridge type 2D electro-hydraulic proportion reversing valve.
Fig. 3 is the structural representation of spool.
Fig. 4 is valve core inside structure sectional view.
Fig. 5 is the sectional view of valve body.
Fig. 6 is the side schematic view of valve body.
Fig. 7 is spool and rolling bearing assembling schematic diagram.
Fig. 8 is the structural representation of top cover.
Fig. 9 is the outer side surface structural representation of sliding wedge.
Figure 10 is the inner side surface structural representation of sliding wedge.
Figure 11 a hydraulic pressure is led control full-bridge side view.
Figure 11 b is that hydraulic pressure is led control full-bridge overall structure schematic diagram.
Figure 12-14 are prestretching-pretwist type full-bridge type 2D electro-hydraulic proportion reversing valve force analysis and movement process figure.
Embodiment
Below in conjunction with accompanying drawing, the utility model is further described.
With reference to Fig. 1～Figure 10, a kind of prestretching-pretwist type full-bridge type 2D electro-hydraulic proportion reversing valve comprises screw 1,3,12,30,33, linear electromechanical converter 2,16, end cap 4,19, linear bearing 5,13,31,32, cylindrical compression spring 21,23, O RunddichtringO 6,11,15,29, pin 7,10,22,24, valve body 8, spool 9, rolling bearing 14,27,36,38, top cover 17,28, bearing pin 18,26, sliding wedge 20,25, marks closely screw 34, steel ball 35, sleeve 37,39.
Prestretching-pretwist type full-bridge type 2D electro-hydraulic proportion reversing valve is turned round coupling three parts by 2D valve, linear electromechanical converter and pressure and is formed.
Described 2D valve portion comprises a spool 9 and a valve body 8, spool 9 is rotatable also can be arranged in valve body 8 endoporus axially slidably, spool 9 two ends, left and right are respectively provided with end shoulders, in valve body inner bore between described end shoulders, have successively T mouth, A mouth, P mouth, B mouth, T mouth, wherein P mouth is liquid entering hole, and this place's pressure is system pressure; Between described end shoulders spool 9 be provided with two middle part shoulders, two middle part shoulders lay respectively at A mouth and B mouth; Each shoulder and valve body inner bore are sealed and matched slidably; It is characterized in that:
The two ends of 2D valve are all turned round coupling by pressure and are connected linear electromechanical converter with spring;
Between spool end shoulders, end cap 4,19 and valve body 8, form left and right sensitive cavity h, j;
As shown in Figure 3, Figure 4, on spool end shoulders, respectively offer a pair of high and low pressure hole (b, d and c, e), pressure hole b, c are through hole, communicate respectively by hole a and spool endoporus h with P mouth; Low pressure hole d, e do not run through spool, are arranged on shoulder axisymmetrically, and communicate with T mouth by the groove of spool end shoulders inner side respectively;
As shown in Figure 5, Figure 6, the two ends on valve body inner bore wall respectively offer a pair of axisymmetric passage (f that experiences
1, f
2and g
1, g
2), respectively with left and right sensitive cavity (h and j) communicate;
As shown in Figure 11 a and 11b, the high and low pressure hole on spool end shoulders, with to experience passage crossing, forms two small opening areas, flowed friction half-bridge in series, and the pressure of two ends sensitive cavity is controlled by respectively the flowed friction half-bridge at two ends.
Described pressure turn round coupling by sliding wedge 20, be fixed on one through two rolling bearings 14 on bearing pin 18 ends of spool end, 38, be installed on the pin 10,22 that linear bearing in sliding wedge hole p, q 13,32, restriction sliding wedge rotate and form; Cylindrical compression spring 21 is arranged between valve body and sliding wedge, and its pre compressed magnitude is slightly larger than spool stroke;
It is the structure that the straight line motion of realizing linear electromechanical converter transfers the twist motion of spool to that pressure is turned round coupling.In this process, can make full use of the feature of 2D valve hydraulic pressure Dao Kongqiao road Pressure gain large (small corner can make the pressure of sensitive cavity that larger variation occurs), by pressure being turned round to the appropriate design of coupling, to drive the torsional moment of valve core rotation to amplify, and make the adverse effect of the non-linear factor comparative example characteristics such as frictional force between spool and spool bore be reduced to minimum degree.
Described O RunddichtringO 6,11 is used for to sealing between end cap and valve body; Described O RunddichtringO 15,29 is used for to sealing between end cap and linear electromechanical converter; The great circle styletable n of described top cover 17,28 is connected with the central inner hole interference fit of sliding wedge 20,25, and the masterpiece of the push rod output of linear electromechanical converter is used on the roundlet styletable m of top cover, and transfers is to sliding wedge.Described linear bearing 5,31 and 13,32 is arranged on respectively in sliding wedge upper and lower two hole p, q symmetrically, the frictional force while slip on pin in order to reduce sliding wedge; The described screw 34 of marking closely withstands on steel ball 35 on an end face of spool endoporus k, is used for one end of spool endoporus k to seal; One end of described sleeve 37,39 withstands on spool, and the other end withstands on the inner ring of rolling bearing 36,38, plays the effect of spring bearing.
Described high and low pressure hole shape is circular, if require the axial motion of spool to have capability of fast response to rotatablely moving, can adopt the rectangular window of large size gradient.
Described linear electromechanical converter is wet type high pressure-resistant proportion electro-magnet, also can select the linear electromechanical converter of other wet type high pressure-resistant.
The working principle of the present embodiment: as shown in figure 12, in the time of the proportion electro-magnet no electric circuit at 2D electro-hydraulic proportional valve two ends, spring produces outside thrust F to sliding wedge
s(left end and right-hand member are represented by subscript " l " and " r " respectively) is passed to spool by two axisymmetric inclined-planes of sliding wedge with the position that two rolling bearings contact.Due to the effect on inclined-plane, spool is except bearing axial tension F
salso bear tangential force F outward,
teffect, with tangential force equal and opposite in direction, the opposite direction of two contact positions in one end, form couple.Axial force and the couple opposite direction of the sliding wedge at two ends to spool, thereby in the time of equilibrium position, the state of spool in prestretching and pretwist.In the time that the proportion electro-magnet of 2D electro-hydraulic proportional valve end is switched on, the thrust F of its generation
mwhile acting on sliding wedge, not only make the axial force disequilibrium of spool, and make the suffered moment of torsion disequilibrium of spool, valve core rotation.For example, in the time that the proportion electro-magnet of left end is switched on, produce electromagnetic push F to the right
ml, the sliding wedge of left end is reduced the active force of spool, all disequilibriums of the axial force that spool two ends are suffered and moment of torsion, spool is subject to axial driving force and anticlockwise torque (seeing from left to right) to the right.Axial driving force is equivalent to the driving force of direct action type proportional valve, under the operating mode of the large flow of high pressure, owing to there being the directly actuating valve core axial motion of hydraulic power and frictional force.But, by reasonably selecting less sliding wedge bevel angle β and larger rolling bearing distribution circular diameter, can obtain larger tangential force, its frictional force drives spool that is enough to overcome spool is rotated counterclockwise.Meanwhile, the sliding wedge at two ends is owing to being subject to the circumferential constraint of pin, take pin as the axis of guide, take linear bearing as supporting slip to the right, the decrement of right-hand member spring reduces, left end amount of spring compression increases, the thrust (seeing Figure 13) of the extra spring force balanced proportions electromagnet that produces.In this process, because spool rotates counterclockwise, the pressure of the left sensitive cavity of valve raises, the pressure decreased of right sensitive cavity, spool moves right, and is subject to the constraint on sliding wedge inclined-plane, two ends in movement process due to the rolling bearing at its two ends, spool in moving right also toward back rotation (clockwise rotating), the pressure of spool two ends sensitive cavity reverts to the equilibrium value of stable state again, and spool arrives a new equilibrium position (see Figure 14) corresponding with proportion electro-magnet thrust size.It needs to be noted, when the pressure of the P of valve mouth was zero (equating with T mouth pressure), now, cannot move axially by the variation actuating valve core of two ends sensitive cavity pressure, but owing to flowing without fluid in valve pocket, spool is not subject to the effect of hydraulic power and clamping force, thereby, the end thrust producing after proportion electro-magnet energising can directly drive valve core movement, and at this moment the working principle of 2D electro-hydraulic proportional valve is consistent with direct action type proportional valve.
Above-mentioned embodiment is used for explaining the utility model; rather than the utility model is limited; in the protection domain of spirit of the present utility model and claim, any modification and change that the utility model is made, all fall into protection domain of the present utility model.
Claims (3)
1. prestretching-pretwist type full-bridge type 2D electro-hydraulic proportion reversing valve, comprise a 2D valve being formed by spool, valve body, spool is rotatable also can be arranged in valve body inner bore axially slidably, two ends, spool left and right are respectively provided with end shoulders, in valve body inner bore between described end shoulders, have successively T mouth, A mouth, P mouth, B mouth, T mouth, wherein P mouth is liquid entering hole, and this place's pressure is system pressure; Between described end shoulders spool be provided with two middle part shoulders, two middle part shoulders lay respectively at A mouth and B mouth; Each shoulder and valve body inner bore are sealed and matched slidably; It is characterized in that:
The two ends of 2D valve are all turned round coupling by pressure and are connected linear electromechanical converter with spring;
Pressure turn round coupling by sliding wedge (10), be fixed on one through two rolling bearings (9) on bearing pin (13) end of spool end, be installed on the linear bearing (3) on sliding wedge, the pin (8) that restriction sliding wedge rotates forms; Spring (4) is arranged between valve body and sliding wedge, and its pre compressed magnitude is slightly larger than valve core stroke;
Between end shoulders, sliding wedge (10) and valve body, form left and right sensitive cavity;
On end shoulders, respectively offer a pair of high and low pressure hole, a, b and e, d, communicate with P mouth and T mouth by spool endoporus respectively; On valve body inner bore wall, two ends respectively offer one and experience passage, c and f, and with left and right sensitive cavity, g and h, communicate respectively; High and low pressure hole on end shoulders, with to experience passage crossing, forms two small opening areas, flowed friction half-bridge in series, and the pressure of two ends sensitive cavity is controlled by respectively the flowed friction half-bridge at two ends.
2. 2D electro-hydraulic proportion reversing valve as claimed in claim 1, is characterized in that: described linear electromechanical converter is proportion electro-magnet.
3. 2D electro-hydraulic proportion reversing valve as claimed in claim 2, is characterized in that: it is 0.5～1.0mm semi-circular cross-section that described damping slot is diameter.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320229517.9U CN203627917U (en) | 2013-04-27 | 2013-04-27 | Pretensioning-pretwisting type full bridge 2D electric-hydraulic proportional reversing valve |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320229517.9U CN203627917U (en) | 2013-04-27 | 2013-04-27 | Pretensioning-pretwisting type full bridge 2D electric-hydraulic proportional reversing valve |
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| Publication Number | Publication Date |
|---|---|
| CN203627917U true CN203627917U (en) | 2014-06-04 |
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ID=50814398
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|---|---|---|---|
| CN201320229517.9U Expired - Fee Related CN203627917U (en) | 2013-04-27 | 2013-04-27 | Pretensioning-pretwisting type full bridge 2D electric-hydraulic proportional reversing valve |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110219846A (en) * | 2019-05-23 | 2019-09-10 | 浙江大学城市学院 | A kind of high-speed driving device towards two-dimensional valve |
| CN111457130A (en) * | 2019-01-22 | 2020-07-28 | 浙江工业大学 | Miniature integrated two-dimensional electromagnetic switch valve |
| CN113339347A (en) * | 2021-06-24 | 2021-09-03 | 河南航天液压气动技术有限公司 | High-pressure high-response plug-in type electro-hydraulic proportional reversing valve |
| CN111457130B (en) * | 2019-01-22 | 2024-06-11 | 浙江工业大学 | Miniature integrated two-dimensional electromagnetic switch valve |
-
2013
- 2013-04-27 CN CN201320229517.9U patent/CN203627917U/en not_active Expired - Fee Related
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111457130A (en) * | 2019-01-22 | 2020-07-28 | 浙江工业大学 | Miniature integrated two-dimensional electromagnetic switch valve |
| CN111457130B (en) * | 2019-01-22 | 2024-06-11 | 浙江工业大学 | Miniature integrated two-dimensional electromagnetic switch valve |
| CN110219846A (en) * | 2019-05-23 | 2019-09-10 | 浙江大学城市学院 | A kind of high-speed driving device towards two-dimensional valve |
| CN110219846B (en) * | 2019-05-23 | 2020-06-02 | 浙江大学城市学院 | High-speed driving device for two-dimensional valve |
| CN113339347A (en) * | 2021-06-24 | 2021-09-03 | 河南航天液压气动技术有限公司 | High-pressure high-response plug-in type electro-hydraulic proportional reversing valve |
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| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20140604 Termination date: 20200427 |