CN85202888U - 3-way plug-in electric controlled liquid ratio direction valve - Google Patents
3-way plug-in electric controlled liquid ratio direction valve Download PDFInfo
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- CN85202888U CN85202888U CN 85202888 CN85202888U CN85202888U CN 85202888 U CN85202888 U CN 85202888U CN 85202888 CN85202888 CN 85202888 CN 85202888 U CN85202888 U CN 85202888U CN 85202888 U CN85202888 U CN 85202888U
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Abstract
The utility model discloses a three-way plug-in mounting type electrohydraulic proportional directional valve, comprising a two-direction electric current control regulating device, a two-direction high-pressure tolerance proportional electromagnet, a valve cover, a pre-guide level, a two-direction three-way plug-in mounting type main level and a plug-in hole body. Double arms drive a differential controlled unit. The utility model has the advantages of a four-edge sliding valve to four-arm involve controlled unit and a two-way plug-in mounting valve single arm controlled unit. Furthermore, the valve adopts the principle of displacement-force feedback and speed-dynamic pressure feedback, so that the static and dynamic performances are improved. Through proper change, the utility model can derive a three-way plug-in mounting type manual adjustment and electrical feedback proportional direction valve.
Description
The present invention is the direction that belongs to convection cell in the liquid control system, the device that flow is realized proportional control.
Traditional four-side---four arms involve controlled flowed friction basic control unit, as servovalve or the direction Proportional valve of employing with four control limits, see Fig. 1, then can realize motion or power proportional control to two-way performer.But because the resistance of four arm liquid of hydraulic pressure full-bridge places on the same spool, rigidity involves mutually, has lost each arm independence controllability.When engineering is used, lost the possibility that pressure or flow parameter to each controlled cavity volume carry out independently controlling and realizing compound control function.Since the quality of guiding valve and size restrictions the dynamic response characteristic of this class valve, and be difficult to make the plug-in type structure.
The two-way plug-in valve that grows up at early seventies is the minimum independent component that constitutes any flowed friction control system as a kind of technological scheme of single armed control flowed friction basic control unit.But adopt a two-way plug-in valve unit block, can not satisfy in the hydraulic system complete control requirements of parameter such as the direction of a controlled cavity volume and flows, for improving the flow control gain of hydraulic pressure half-bridge, the control of two brachium pontis intends adopting the synchronization discrepancy flowing mode, adopt a pair of two-way plug-in valve to be combined into the hydraulic pressure half-bridge, this has not only increased the technical difficulty of two arm synchronization control, and also not compact on the structure, referring to Fig. 2.
Technological scheme of the present invention is that employing threeway cartridge valve---both arms involve differential controlled hydraulic pressure half-bridge basic control unit, see Fig. 3.Its compatibility the advantage of above two kinds of technological schemes, compact structure not only, and ride gain increases.If control the direction and the flow of single-acting or double-action differential cylinder, only need such plug-in unit with it.It has more on the principle with respect to four-side and two-way plug-in valve and structural rationality, novelty.The spy has proposed the present invention for this reason.
The present invention is: the threeway type plug-in electro-hydraulic ratio directional control valve (see figure 4) that can in high-pressure fluid medium, work, and it is made up of six parts, i.e. bidirectional current controlled adjuster (1); Two-way high pressure resistant proportionality electromagnet (2); Valve gap (3); The sliding valve style pilot stage; Two-way threeway plug-in type main; Receptacle body (4).
Threeway type plug-in electro-hydraulic ratio directional control valve involves differential controlled hydraulic pressure half-bridge control unit as both arms, its main is a threeway plug-in type guiding valve that has two control valve ports (29), (30), and main valve plug epicoele (31) is as the controlled cavity volume of pilot valve control.Main valve plug (22) is two-way controlled with respect to the no signal meta, and pilot stage also is that to disturb the no signal meta relatively be two-way controlled hydraulic pressure half-bridge, and valve gap (3) is the adpting flange that pilot stage and proportion electro-magnet (2) and main join together.
As further description: main valve plug (22) and guide's spool (11) coaxial arrangement, connect by feedback spring (15) therebetween, the displacement of main valve plug (22) is converted into the spring force of feedback spring (15), acts on guide's spool (11), balances each other with the electromagnetic force of importing.Realize the closed loop control of " displacement-force feedback " of valve inside.Make this valve have steady state controling precision preferably.This device also is provided with damper (32) between main and pilot stage simultaneously, has realized inter-stage " speed---dynamic pressure feedback ", has improved the dynamic characteristic of valve.
Mechanical centering when the main valve plug of threeway type plug-in electro-hydraulic ratio directional control valve (22) adopts single spring (20) to realize no signal has in addition replaced the structure of two spring mechanical centerings of conventional direction valve, thereby has made this device more compact.
This installs an available corresponding hand adjustment mechanism (40) and replaces proportion electro-magnet (2), can derive threeway plug-in type hand adjustment proportion directional valve.(see figure 5), and the static and dynamic performance and the electrohydraulic proportional directional valve of hand adjustment proportion directional valve are similar.
The also available high pressure resistant displacement transducer of this device detects the displacement signal of main valve plug, then this displacement signal is converted to voltage signal, feed back on the bidirectional current controlled adjuster (1), compare, realize the closed loop control of " displacement---electricity feedback " in the valve with the voltage signal of transfer valve.Its static properties is better than electrohydraulic proportional directional valve.
Be three kinds of embodiments of the present invention below, description and accompanying drawing by embodiment have provided details of the present invention.
Accompanying drawing 4 is organigrams of first embodiment of the present invention.Appellation threeway type plug-in electro-hydraulic ratio directional control valve is called for short electrohydraulic proportional directional valve below.Parts among the figure (1) are the bidirectional current controlled adjusters, and it offers proportion electro-magnet (2) with two-way control electrical signal.Parts (2) are two-way high pressure resistant proportionality electromagnets, and it gives guide's spool (11) input bi-directional electromagnetic power, and parts (2) have following two characteristics: output electromagnetic force and input electrical signal are proportional; When signal was constant, its output electromagnetic force and armature (7) displacement were irrelevant.Valve gap (3) is made hollow, and sliding valve style pilot stage parts are equipped with on its top.Have radial and axial guide in it and control runner (10), (14), (35).The upper-end surface of valve gap (3) is connected by screw (6) with proportion electro-magnet (2).Valve gap (3) is connected by screw (8) with receptacle body (4).It comprises sliding valve style pilot stage parts: be contained in cushion block (9) and guide's spool (11) in guide's valve pocket (12), guide's spool (11) upper end is connected with cushion block (9), the lower end is connected with feedback spring (15), the damper (32) that is provided with between main and pilot stage and links up with runner (10), valve port (33) on guide's valve pocket (12), (34) can make rectangle or circle according to different requirements.Guide's spool (11) is two controls limit guiding valve.Cushion block (9) can resize ratio electromagnet (2) armature (7) and the no signal meta of guide's spool (11).It comprises two-way threeway plug-in type main parts: be contained in the main valve plug (22) in the main valve housing (23), by the pull bar (24) that is connected with main valve plug, be inserted in the lower spring cup (21) that is contained in the main valve housing (23) successively, main spring (20), upper spring seat (19), with adjust nut (18) and be connected, and with locking nut (16), (17) are fixed.Main valve plug (22) is the two-way control guiding valve of secondary concentric column.Primary valve (30) on the main valve housing (23), (29) can be rectangle or circle according to different requirements.Pack into the lower end of valve gap (3), the upper end of main valve housing (23).Adjust nut (18) and can adjust the pre compressed magnitude of main spring.Wait other part combination by locking nut (16), (17), adjustment nut (18), upper spring seat (19), main spring (20), lower spring (21), pull bar (24), carry out the mechanical centering function of main valve plug (22), primary valve (29), (30) can be controlled the direction and the flow of system fluid.Receptacle body (4) is made hollow, and interior dress threeway plug-in type main parts also have control runner (28) and externally are connected oilhole P mouth (27), A mouth (26), and O mouth (25), the pressure of P mouth is made as P
1, the pressure of cavity volume (31) is made as P
3P mouth (27) is axial arranged, and A mouth (26) and O mouth (25) are radial arrangement, and P mouth (27) also can be exchanged setting with O mouth (25), will make corresponding changes but the guide controls runner.
Its working principle is: when the no input electrical signal of proportion electro-magnet (2), guide's spool (11) mediates under the effect of zeroing spring (5) and feedback spring (15), guide's fluid from P mouth (27) through runner (28), (35) by valve port (34), flow through valve port (33), runner (14) of cavity volume (13) flow to O mouth (25).During stable state, the pressure of controlled chamber (31) equates with the pressure of cavity volume (13).(31) pressure with (36) two chambeies equates.Because main valve plug (22) is the hydraulic coupling of two ends and the pre-compression force of main spring (20) up and down, and main valve plug (22) is mediated, and does not have flow to pass through primary valve (29) and (30), inlet pressure P no matter
1How high, valve is in reliable closed condition, has protected load.
When input during one positive current, at first to+Y direction motion, valve port (34) turns down guide's spool (11), and valve port (33) increases, the pressure P of controlled cavity volume (31)
3Reduce, main valve plug (22) is at P
1-P
3The pressure difference effect under, overcome friction, spring force, the power of surging move, have obtained and the proportional displacement Z of input electrical signal to+Z direction.Main flow flows to A mouth (26) from P mouth (27).In like manner, when the input negative current, the controlled chamber pressure P
3Raise, obtained and the proportional main valve plug displacement-Z of input electrical signal.Main flow flows to O mouth (25) from A mouth (26).When system is subjected to external interference, system pressure P for example
1Reduce suddenly, and input positive current signal is a certain setting, main valve plug displacement Z has the trend of minimizing, feedback spring (15) amount of deformation reduces, because electromagnetic force is constant, then guide's spool (11) will move a distance to+Y direction, and valve port (34) turns down, valve port (33) increases, so the pressure P of controlled chamber (31)
3Reduce, main valve plug (22) returns to or approaches original equilibrium position to the displacement of+Z direction.The principle of " displacement---force feedback " in Here it is the valve.The existence of this internal feedback has limited the pressure and the temperature drift of valve characteristic.Electrohydraulic proportional directional valve has output main valve plug bidirectional displacement ± Z and the proportional characteristic of input electrical signal.The bidirectional traffics of its output are not only relevant with the area of passage of primary valve (30) or (29), but also relevant with the operating pressure differential of primary valve.
Replace proportion electro-magnet (2) among first embodiment with hand adjustment mechanism (40), and remove bidirectional current controlled adjuster (1), promptly constitute present embodiment.Accompanying drawing 5 is organigrams of second embodiment of the present invention.Appellation threeway plug-in type hand adjustment proportion directional valve, except that hand adjustment mechanism, all the other are all same Fig. 4 of code name of part in addition.Hand adjustment mechanism (40) comprising: regulating handle (42), adjusting screw rod (43), hand adjustment mechanism body part (47), it is the hollow steel part of a circular upper part and square lower part, between it and the valve gap (3) by screw (46) mechanical coupling.Regulation spring (49), its end is connected with steel ball (50), the other end is connected with cushion block (9) on guide's spool, graduated ring (51), lock screw (52), stop screw (41) plays seal action between high pressure cavity volume (53) and zero-pressure chamber (44) at the O RunddichtringO (45) on the adjusting screw rod.
Its working procedure is: adjust regulating handle (42), make the zero line of its edge, lower end aligning graduated ring (51), tighten lock screw (52), adjusting screw rod this moment (43) is by steel ball (50) pressure spring (49), this spring force makes guide's spool (11) under feedback spring (15) and Regulation spring (49) act on, and is in no signal meta position.If handle with sleeve (42), handle (42) rotates with screw rod (43), promoting steel ball (50) in axial direction moves, compression or loosen Regulation spring (49), changed the active force that imposes on guide's spool, so the aperture of the valve port of pilot valve (34), (33) changes, and then the pressure P of main valve cavity volume (31)
3Change.So main valve plug (22) moves under the pressure difference effect of two ends up and down.Regulating handle for hand adjustment mechanism rotates an angle along clockwise direction, and the displacement+Z output of the main valve plug of a correspondence is just arranged.In like manner, rotate an angle in the counterclockwise direction, the main valve plug displacement-Z output of a correspondence is just arranged for handle.The angle that is output displacement and the handle rotation of valve is directly proportional, and its inside also contains the principle of what is called " displacement---force feedback " and " speed---dynamic pressure is fed back ", so its static and dynamic performance and electrohydraulic proportional directional valve are similar.
The 3rd embodiment of the present invention, as shown in Figure 6, appellation threeway plugged electric feedback proportional direction valve.(in the present embodiment except that with first embodiment in the different newly organized code names of parts in addition, all same Fig. 4 of all the other code names) it is made of eight parts, has increased by two parts than embodiment's scheme shown in Figure 4; The high pressure resistant displacement transducer parts of the first (61), parts (61) comprise displacement transducer body (62), induction rod (63) and nut (64).Displacement transducer (61) and main valve plug (22) coaxial arrangement.It two is measuring amplifier parts (60).(15) be feedback spring, but do not play feedback effect, guide's spool (11) is resetted at this.(66) be spring seat.Valve gap (3) has two through holes, and sliding valve style pilot stage and spring seat (66) are installed in one hole, the left side.The upper end in one hole, the right is a screw, in order to fixing high pressure resistant displacement transducer body (62), and pack into the lower end of valve gap (3) of the big end of main valve housing (23).Induction rod (63) one ends insert displacement transducer body (62), and the other end has screw thread, is connected with nut (64).The other end of nut (64) is connected with the pull bar (24) of main valve plug.Main valve plug (22) can drive induction rod and move together, displacement transducer detects the signal of the displacement Z of main valve plug (22), and be converted into voltage signal linearly, this signal amplifies through measuring amplifier (60), feeding back to bidirectional current controlled adjuster (1) upward compares with the input electrical signal of setting, its difference is input to proportion electro-magnet (2), revise the value of main valve plug output displacement, output main valve plug displacement is reached or near setting value, the loop control theory that Here it is so-called " displacement---electricity feedback ".Damper (32) still plays a part " speed---dynamic pressure feedback ".Its static properties is better than electrohydraulic proportional directional valve.
More than three kinds of embodiment direction that is convection cell, the device that flow is realized control, its main feature is as follows:
(1) output main valve plug displacement Z can two-way, continuous, proportion control. No zero-bit dead band. When no input electrical signal, no matter how high system pressure is, do not have main flow to pass through this valve. Can protect load like this.
(2) static characteristic good linearity, the ring that stagnates is little; The dynamic characteristic frequency f－3dbSimilar products height than four-side and two-way plug-in valve.
(3) work bandwidth 20HZ with the little engineering hydraulic system of interior load variations in, only use a threeway type plug-in electro-hydraulic ratio direction valve, can ratio direction and the speed of ground control single-acting or double acting differential cylinder. Simplified widely system. It can also constitute the Electro-hydraulic Proportional Displacement pump with variable pump.
(4) this product can be electric-hydraulic proportion control, can be hand adjustment control, can be that " force feedback type " also can be " electric reaction type ".
(5) to connect form can be board-like, tubular type and card format for this product.
(6) because having, it compares beautiful control characteristic of steady state and higher worker with servo valve Make frequency range. And cheap, operting differential pressure is low, working media is not had the characteristics of specific (special) requirements, makes it might replace the general industry servo valve, will be widely used in the engineering hydraulic control system.
Claims (9)
1, a kind of threeway type plug-in electro-hydraulic ratio directional control valve, it comprises bidirectional current controlled adjuster [1], two-way high pressure resistant proportionality electromagnet [2], feature of the present utility model is, it also comprises valve gap [3], sliding valve style pilot stage parts, two-way threeway plug-in type main parts by feedback spring [15] connection, receptacle body [4], above-mentioned sliding valve style pilot stage parts, it comprises cushion block [9] and the guide's spool [11] that is contained in guide's valve pocket [12], guide's spool [11] upper end is connected with cushion block [9], the lower end is connected with feedback spring [15], the damper [32] that is provided with between main and pilot stage and links up with runner [10], above-mentioned two-way threeway plug-in type main parts, it comprises the main valve plug [22] that is contained in the main valve housing [23], by the pull bar [24] that is connected with main valve plug [22], be inserted in the lower spring cup [21] that is contained in the main valve housing [23] successively, main spring [20], upper spring seat [19], with adjust nut [18] and be connected, and with locking nut [16], [17] are fixed.
2, electrohydraulic proportional directional valve according to claim 1, it is characterized in that, above-mentioned valve gap (3), receptacle body (4) is all made hollow, have the guide and control runner (10), (14), (35) and control runner (28), top setting slide valve formula pilot stage parts in the middle of it, two-way threeway plug-in type main parts are settled in the bottom.Valve gap (3) upper-end surface is connected by screw (6) with two-way high pressure resistant proportionality electromagnet (2).Pack into the lower end of valve gap (3), main valve housing (23) upper end, valve gap (3) is connected by screw (8) with receptacle body (4).
3, electrohydraulic proportional directional valve according to claim 1 is characterized in that, above-mentioned guide's spool (11) is bilateral control guiding valve, and main valve plug (22) is the concentric sleeve valve of secondary, and main valve is a threeway plug-in type structure.
4, threeway type plug-in electro-hydraulic ratio directional control valve according to claim 1, it is characterized in that, three oil throughs of above-mentioned receptacle body, P mouth (27) is axial arranged, O mouth (25), A mouth (26) are radial arrangement, P mouth (27), O mouth (25) also can be exchanged setting, will do corresponding change but the guide controls runner.
5, electrohydraulic proportional directional valve according to claim 1 is characterized in that, above-mentioned two-way high pressure resistant proportionality electromagnet (2) replaces with hand adjustment mechanism (40), removes bidirectional current controlled adjuster (1), is threeway plug-in type hand adjustment proportion directional valve.
6, according to claim 1 to 5 described threeway type plug-in electro-hydraulic ratio directional control valve or threeway plug-in type hand adjustment proportion directional valve, it is characterized in that, main valve plug (22) and guide's spool (11) are coaxial arrangement, connect by feedback spring (15) therebetween, realize the closed loop control of " displacement---force feedback " in the valve, damper (32) is set between pilot stage and main, realizes inter-stage " speed---dynamic pressure feedback ".
7, electrohydraulic proportional directional valve according to claim 1, it is characterized in that, increase measuring amplifier parts (60) and high pressure resistant displacement transducer parts (61), promptly constitute threeway plugged electric feedback proportional direction valve, displacement transducer (61) is a coaxial arrangement with main valve plug (22), displacement transducer (61) detects the displacement of main valve plug (22), realize " displacement---electricity feedback " closed loop control in the valve, damper (32) is realized inter-stage " speed---dynamic pressure feedback " control.
8, according to claim 1 or 5 or 7 described three kinds of proportion directional valves, it is characterized in that the valve port (33) on the primary valve (29) on the main valve housing (23) and (30) and the guide's valve pocket (12) and (34) can have the shape of rectangle or circle by different requirement.
According to claim 1 or 5 or 7 described three kinds of proportion directional valves, it is characterized in that 9, that their product form has is board-like, tubular type and card format.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 85202888 CN85202888U (en) | 1985-07-11 | 1985-07-11 | 3-way plug-in electric controlled liquid ratio direction valve |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 85202888 CN85202888U (en) | 1985-07-11 | 1985-07-11 | 3-way plug-in electric controlled liquid ratio direction valve |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN85202888U true CN85202888U (en) | 1987-03-25 |
Family
ID=4798593
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 85202888 Expired - Lifetime CN85202888U (en) | 1985-07-11 | 1985-07-11 | 3-way plug-in electric controlled liquid ratio direction valve |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN85202888U (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102588372A (en) * | 2012-03-09 | 2012-07-18 | 太原理工大学 | Electro-hydraulic proportional relief valve |
| CN102619815A (en) * | 2011-01-27 | 2012-08-01 | 天津市友达机电液成套设备有限公司 | Hydraulic system flow collector with bypass function |
| CN102840189A (en) * | 2012-09-25 | 2012-12-26 | 北京机械设备研究所 | Combined hydraulic oil bridge |
| CN108561357A (en) * | 2018-01-20 | 2018-09-21 | 邵立坤 | A kind of plug-in proportional pressure control valve |
| CN112682377A (en) * | 2020-12-22 | 2021-04-20 | 西安航天远征流体控制股份有限公司 | Valve core, axial flow type regulating valve and axial flow type regulating valve system |
-
1985
- 1985-07-11 CN CN 85202888 patent/CN85202888U/en not_active Expired - Lifetime
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102619815A (en) * | 2011-01-27 | 2012-08-01 | 天津市友达机电液成套设备有限公司 | Hydraulic system flow collector with bypass function |
| CN102619815B (en) * | 2011-01-27 | 2015-01-21 | 天津程普工程机械有限公司 | Hydraulic system flow collector with bypass function |
| CN102588372A (en) * | 2012-03-09 | 2012-07-18 | 太原理工大学 | Electro-hydraulic proportional relief valve |
| CN102588372B (en) * | 2012-03-09 | 2014-12-03 | 太原理工大学 | Electro-hydraulic proportional relief valve |
| CN102840189A (en) * | 2012-09-25 | 2012-12-26 | 北京机械设备研究所 | Combined hydraulic oil bridge |
| CN108561357A (en) * | 2018-01-20 | 2018-09-21 | 邵立坤 | A kind of plug-in proportional pressure control valve |
| CN112682377A (en) * | 2020-12-22 | 2021-04-20 | 西安航天远征流体控制股份有限公司 | Valve core, axial flow type regulating valve and axial flow type regulating valve system |
| CN112682377B (en) * | 2020-12-22 | 2023-01-03 | 西安航天远征流体控制股份有限公司 | Valve core, axial flow type regulating valve and axial flow type regulating valve system |
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