CN102788056A - Hydraulic control system of electro-hydraulic feedback proportion throttle cartridge valve - Google Patents
Hydraulic control system of electro-hydraulic feedback proportion throttle cartridge valve Download PDFInfo
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- CN102788056A CN102788056A CN2012102981277A CN201210298127A CN102788056A CN 102788056 A CN102788056 A CN 102788056A CN 2012102981277 A CN2012102981277 A CN 2012102981277A CN 201210298127 A CN201210298127 A CN 201210298127A CN 102788056 A CN102788056 A CN 102788056A
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Abstract
The invention relates to a hydraulic control system of an electro-hydraulic feedback proportion throttle cartridge valve, in particular to a hydraulic control system device of heavy-flow pilot valve proportion control flow in engineering machinery. A main valve oil inlet and a main valve oil outlet are respectively arranged at the sides of a main valve bush; one end of a main valve throttling groove is communicated with a second one-way valve; the other end of the main valve throttling groove is communicated with a main valve containing cavity; a control cover board is axially provided with a displace feedback rod and a displacement sensor; a pilot valve core is arranged inside an axial hole of the pilot valve body; a pilot spring is arranged between the pilot valve core and a blind nut; a control oil port is communicated with a first one-way valve; the first one-way valve is communicated with the main valve containing cavity; the control oil port is communicated with a work oil outlet of the pilot valve; an oil inlet of the pilot valve is communicated with the main valve containing cavity; and a pilot oil return port is communicated with one end of the pilot valve core. The hydraulic control system has the beneficial effects that the structure is simple; the operation is convenient; the hydraulic control system can be instantaneously opened and controlled by proportion; the electro-hydraulic closed loop is in feedback control; the linearity is high; the hysteresis is small; the position of the main valve core is detected on line; and the hydraulic control system is widely applied to the hydraulic control system of construction machinery industry.
Description
Technical field
The present invention relates to the hydraulic control system equipment of large-flow-rate pilot valve proportional control flow in a kind of electric throttling of liquid the feedback proportional cartridge valve hydraulic control system, particularly engineering machinery.
Background technique
At present, used throttle valve adopts mostly in the hydraulic machinery is manual structure, can not adopt computer control, and the computer-controlled proportional throttle valve of employing is also arranged; But complex structure, control mode are to adopt two ACTIVE CONTROL, and the guide who controls this valve is partly for servovalve, though control accuracy is high; But cost is also higher, can not adapt to most of occasions, and can not reliably close during the fluid reverse flow, influences the hydraulic system trouble free service; And complex structure, external form is bulky, and it is bigger to take up room, the control section complex structure; Turbidity test to fluid require height, cause rate of fault high, and maintenance is inconvenient.
Summary of the invention
The object of the invention provides a kind of electric liquid feedback proportional throttling cartridge valve hydraulic control system, and it is that pilot stage adopts the control of hydraulic pilot valve, and main adopts the cartridge valve mode of structure; Be provided with the dynamic hydraulic damping between pilot stage and the main, main valve plug is provided with displacement transducer, and the position feedback of displacement transducer feedback main valve is given amplifier; Carry out closed loop control, reach the spool ratio and open, response rapidly; Reverse closed safe is reliable; The linearity is high, and the ring that stagnates is little, and realization spool ratio open response is oppositely closed the purpose of hydraulic control rapidly.
The present invention electricity liquid feedback proportional throttling cartridge valve hydraulic control system takes following technological scheme to realize: it is to be made up of main valve filler opening, main valve housing, main valve oil outlet, main valve plug, main valve throttling groove, main valve cavity volume, guide's return opening, blind nut, guide's spring, guide's spool, guide's valve body, amplifier, proportion electro-magnet, displacement transducer, Displacement Feedback bar, pilot valve filler opening, control cover plate, number one one-way valve, pilot valve actuator port, control port, No. second one-way valve and cross throttling groove, and the side of main valve housing is provided with main valve filler opening and main valve oil outlet respectively, installs main valve plug in the axial bore of main valve housing; One-way valve is set in the main valve plug axial bore No. second; Main valve plug one end is provided with cross throttling groove, and the main valve plug the other end is provided with the main valve throttling groove, and main valve throttling groove one end is communicated with No. second one-way valve; The main valve throttling groove the other end is communicated with the main valve cavity volume; The control cover plate device is in main valve housing upper end, control cover plate axial device Displacement Feedback bar and displacement transducer, and Displacement Feedback bar one end connects main valve plug; The Displacement Feedback bar the other end is nested with in the displacement transducer axial bore; The control cover plate side is provided with guide's valve body, device guide spool in the pilot valve body axial bore, guide's spool one end device blind nut; Device guide spring between guide's spool and the blind nut; Guide's spool the other end device proportion electro-magnet, the proportion electro-magnet side is provided with amplifier, and the control cover plate both sides are provided with control port and guide's return opening respectively; Control port is communicated with the number one one-way valve; The number one one-way valve is communicated with the main valve cavity volume, and control port is communicated with the pilot valve actuator port, and the pilot valve filler opening is communicated with the main valve cavity volume; Guide's return opening is communicated with guide's spool one end, realizes the effect of the hydraulic control of electric liquid feedback proportional throttling cartridge valve in the large-flow-rate pilot valve proportional control flow.
Working procedure of the present invention is following: when amplifier does not have signal, and the proportion electro-magnet attonity, guide's spool is in closed condition; Pressure oil gets into the main valve throttling groove through No. second one-way valve, and pressure oil gets into the main valve cavity volume through the main valve throttling groove, and pressure oil gets into the number one one-way valve; This moment, the number one one-way valve was a closed condition; Pressure oil gets into guide's spool simultaneously, because guide's spool is a closed condition, is pressed so produce behind the pressure oil entering main valve cavity volume; Because the area of guide's cavity volume is greater than the area of main valve filler opening, so main valve plug is in closed condition.When amplifier had certain signal, proportion electro-magnet produced certain thrust promotion guide spool and moves, and overcomes the power of guide's spring; Guide's spool moves certain distance, and the pilot valve filler opening is opened certain opening to the path of pilot valve actuator port, and the pressure oil in the main valve cavity volume gets into control port through this opening; Release a part of pressure of main valve cavity volume, when the pressure in the main valve cavity volume is little to a certain degree the time, main valve plug is just opened certain distance; This moment, the opening of main valve throttling groove also and then became big, and when the flow that the flow that passes through up to the main valve throttling groove and guide's spool pass through was suitable, main valve plug just was in state of equilibrium; The displacement amount of main valve plug can pass through displacement transducer and feed back to amplifier; Amplifier can carry out infinitesimal calculus relatively to this signal and instruction signal, carries out closed loop control, realizes ratio throttling control flow rate.When electrical signal reduces to zero suddenly, and the pressure of main valve oil outlet is when high, and the pressure oil of main valve oil outlet gets into the main valve cavity volume through the number one one-way valve; The pressure of main valve cavity volume raises, and makes main valve plug close rapidly, guarantees the safe operation of equipment like this; Reach the spool ratio and open, response is rapid, and closed safe is reliable; The linearity is high, and the ring that stagnates is little, realizes the effect of hydraulic control in the large-flow-rate pilot valve proportional control flow.
The effect of the present invention's electricity liquid feedback proportional throttling cartridge valve hydraulic control system is simple in structure, and is easy to operate, instantaneous unlatching; Proportional control, the spool realization is safe and reliable closes and opens, and adopts electric liquid close-loop feedback control; The linearity is high, and the ring that stagnates is little, and control degree and reliability are high; The position of online detection main valve plug is widely used on the hydraulic control system of construction machinery industry.
Description of drawings
The present invention's electricity liquid feedback proportional throttling cartridge valve hydraulic control system will combine accompanying drawing to describe in further detail.
Fig. 1 is the structural representation of the present invention's electricity liquid feedback proportional throttling cartridge valve hydraulic control system.
Fig. 2 is the hydraulic control system structural representation of the present invention's electricity liquid feedback proportional throttling cartridge valve hydraulic control system.
1-main valve oil-in, 2-main valve housing, 3-main valve oil-out, 4-main valve plug, 5-main valve throttling channel, 6-main valve cavity volume, 7-guide oil return opening, 8-blind nut, 9-guide spring, 10-guide spool, 11-guide valve body, 12-amplifier, 13-proportion electro-magnet, 14-displacement transducer, 15-Displacement Feedback bar, 16-pilot valve oil-in 17-21-No. the second check valve of control cover plate 18-number one check valve 19-pilot valve actuator port 20-control port, 22-cross throttling channel.
Embodiment
With reference to Fig. 1,2; The present invention electricity liquid feedback proportional throttling cartridge valve hydraulic control system: it is to be made up of main valve filler opening 1, main valve housing 2, main valve oil outlet 3, main valve plug 4, main valve throttling groove 5, main valve cavity volume 6, guide's return opening 7, blind nut 8, guide's spring 9, guide's spool 10, guide's valve body 11, amplifier 12, proportion electro-magnet 13, displacement transducer 14, Displacement Feedback bar 15, pilot valve filler opening 16, control cover plate 17, number one one-way valve 18, pilot valve actuator port 19, control port 20, No. second one-way valve 21 and cross throttling groove 22, and the side of main valve housing 2 is provided with main valve filler opening 1 and main valve oil outlet 3 respectively, device main valve plug 4 in the axial bore of main valve housing 2; One-way valve 21 is set No. second in main valve plug 4 axial bores; Main valve plug 4 one ends are provided with cross throttling groove 22, and main valve plug 4 the other ends are provided with main valve throttling groove 5, and main valve throttling groove 5 one ends are communicated with No. second one-way valve 21; Main valve throttling groove 5 the other ends are communicated with main valve cavity volume 6; Control cover plate 17 is installed in main valve housing 2 upper ends, control cover plate 17 axial device Displacement Feedback bars 15 and displacement transducers 14, and Displacement Feedback bar 15 1 ends connect main valve plug 4; Displacement Feedback bar 15 the other ends are nested with in displacement transducer 14 axial bores; Control cover plate 17 sides are provided with guide's valve body 11, device guide spool 10 in guide's valve body 11 axial bores, guide's spool 10 1 end device blind nuts 8; Device guide spring 9 between guide's spool 10 and the blind nut 8; Guide's spool 10 the other end device proportion electro-magnets 13, proportion electro-magnet 13 sides are provided with amplifier 12, and control cover plate 17 both sides are provided with control port 20 and guide's return opening 7 respectively; Control port 20 is communicated with number one one-way valve 18; Number one one-way valve 18 is communicated with main valve cavity volume 6, and control port 20 is communicated with pilot valve actuator port 19, and pilot valve filler opening 16 is communicated with main valve cavity volume 6; Guide's return opening 7 is communicated with guide's spool 10 1 ends, realizes the effect of the hydraulic control of electric liquid feedback proportional throttling cartridge valve in the large-flow-rate pilot valve proportional control flow.
The embodiment of the present invention's electricity liquid feedback proportional throttling cartridge valve hydraulic control system, working procedure of the present invention is following: when amplifier 12 does not have signal, proportion electro-magnet 13 attonitys; Guide's spool 10 is in closed condition; Pressure oil gets into main valve throttling groove 5 through No. second one-way valve 21, and pressure oil gets into main valve cavity volume 6 through main valve throttling groove 5, and pressure oil gets into number one one-way valve 18; Number one one-way valve 18 is closed conditions at this moment; Pressure oil gets into guide's spool 10 simultaneously, because guide's spool 10 is closed conditions, is pressed so pressure oil gets into the 6 back generations of main valve cavity volume; Because the area of guide's cavity volume 6 is greater than the area of main valve filler opening 1, so main valve plug 4 is in closed condition.When amplifier 12 had certain signal, proportion electro-magnet 13 produced certain thrust promotion guide spool 10 and moves, and overcomes the power of guide's spring 9; Guide's spool 10 moves certain distance, and pilot valve filler opening 16 is opened certain opening to the path of pilot valve actuator port 19, and the pressure oil in the main valve cavity volume 6 gets into control port 20 through this opening; Release a part of pressure of main valve cavity volume 6; When the pressure in the main valve cavity volume 6 is little to a certain degree the time, main valve plug 4 is just opened certain distance, and this moment, main valve throttling groove 5 opening also and then became big; When the flow that the flow that passes through up to main valve throttling groove 5 and guide's spool 10 pass through is suitable; Main valve plug 4 just is in state of equilibrium, and the displacement amount of main valve plug 4 can pass through displacement transducer 14 and feed back to amplifier 13, and amplifier 13 can carry out infinitesimal calculus relatively to this signal and instruction signal; Carry out closed loop control, realize ratio throttling control flow rate.When electrical signal reduces to zero suddenly, and the pressure of main valve oil outlet 3 is when high, and the pressure oil of main valve oil outlet 3 gets into main valve cavity volumes 6 through number one one-way valve 18; The pressure of main valve cavity volume 6 raises, and makes main valve plug 4 close rapidly, guarantees the safe operation of equipment like this; Reach the spool ratio and open, response is rapid, and closed safe is reliable; The linearity is high, and the ring that stagnates is little, realizes the effect of hydraulic control in the large-flow-rate pilot valve proportional control flow.
Claims (1)
1. electric liquid feedback proportional throttling cartridge valve hydraulic control system; It is to be made up of main valve filler opening (1), main valve housing (2), main valve oil outlet (3), main valve plug (4), main valve throttling groove (5), main valve cavity volume (6), guide's return opening (7), blind nut (8), guide's spring (9), guide's spool (10), guide's valve body (11), amplifier (12), proportion electro-magnet (13), displacement transducer (14), Displacement Feedback bar (15), pilot valve filler opening (16), control cover plate (17), number one one-way valve (18), pilot valve actuator port (19), control port (20), No. second one-way valve (21) and cross throttling groove (22); The side that it is characterized in that main valve housing (2) is provided with main valve filler opening (1) and main valve oil outlet (3) respectively; Device main valve plug (4) in the axial bore of main valve housing (2); In main valve plug (4) axial bore No. second one-way valve (21) is set; Main valve plug (4) one ends are provided with cross throttling groove (22); Main valve plug (4) the other end is provided with main valve throttling groove (5); Main valve throttling groove (5) one ends are communicated with No. second one-way valve (21), and main valve throttling groove (5) the other end is communicated with main valve cavity volume (6), and control cover plate (17) device is in main valve housing (2) upper end; Control cover plate (17) axial device Displacement Feedback bar (15) and displacement transducer (14); Displacement Feedback bar (15) one ends connect main valve plug (4), and Displacement Feedback bar (15) the other end is nested with in displacement transducer (14) axial bore, and control cover plate (17) side is provided with guide's valve body (11); Device guide's spool (10) in guide's valve body (11) axial bore; Guide's spool (10) one end device blind nuts (8), device guide's spring (9) between guide's spool (10) and the blind nut (8), guide's spool (10) the other end device proportion electro-magnet (13); Proportion electro-magnet (13) side is provided with amplifier (12); Control cover plate (17) both sides are provided with control port (20) and guide's return opening (7) respectively, and control port (20) is communicated with number one one-way valve (18), and number one one-way valve (18) is communicated with main valve cavity volume (6); Control port (20) is communicated with pilot valve actuator port (19); Pilot valve filler opening (16) is communicated with main valve cavity volume (6), and guide's return opening (7) is communicated with guide's spool (10) one ends, realizes the hydraulic control of electric liquid feedback proportional throttling cartridge valve in the large-flow-rate pilot valve proportional control flow.
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| Application Number | Priority Date | Filing Date | Title |
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| CN2012102981277A CN102788056A (en) | 2012-08-21 | 2012-08-21 | Hydraulic control system of electro-hydraulic feedback proportion throttle cartridge valve |
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| CN2012102981277A CN102788056A (en) | 2012-08-21 | 2012-08-21 | Hydraulic control system of electro-hydraulic feedback proportion throttle cartridge valve |
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| CN2012102981277A Pending CN102788056A (en) | 2012-08-21 | 2012-08-21 | Hydraulic control system of electro-hydraulic feedback proportion throttle cartridge valve |
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Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102927074A (en) * | 2012-11-22 | 2013-02-13 | 兰州理工大学 | Anti-cavitation high frequency response and high flow proportional cartridge valve |
| CN107654430A (en) * | 2017-09-29 | 2018-02-02 | 上海立新液压有限公司 | A kind of high frequency sound twin-stage proportional direction valve and its proportion directional control method |
| CN107725842A (en) * | 2017-11-08 | 2018-02-23 | 宁波文泽机电技术开发有限公司 | The ratio one-way flow valves of double-direction control |
| CN108757621A (en) * | 2018-08-14 | 2018-11-06 | 三河沃达液压控制***有限公司 | Indirect control formula digital servo valve |
| CN109372813A (en) * | 2018-11-30 | 2019-02-22 | 武汉船用机械有限责任公司 | A kind of electro-hydraulic proportional throttle valve and its control method |
| CN109854550A (en) * | 2017-11-30 | 2019-06-07 | 徐工集团工程机械股份有限公司科技分公司 | Hydraulic control system and engineering machinery |
| CN112576566A (en) * | 2020-12-07 | 2021-03-30 | 重庆红江机械有限责任公司 | Displacement feedback proportional flow control valve |
| CN113236623A (en) * | 2021-06-16 | 2021-08-10 | 太原理工大学 | Electro-hydraulic proportional direction valve with independently controlled valve port |
| CN114215924A (en) * | 2021-12-17 | 2022-03-22 | 油威力液压科技股份有限公司 | Pilot valve spool flat-turn combined special-shaped through-flow port large-flow cartridge valve |
| CN115095572A (en) * | 2022-07-21 | 2022-09-23 | 湖南十开科技有限公司 | Double-acting electro-hydraulic proportional push rod and electro-hydraulic proportional multi-way valve |
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| CN202789805U (en) * | 2012-08-21 | 2013-03-13 | 山东泰丰液压股份有限公司 | Hydraulic control device of electro-hydraulic feedback proportional throttling cartridge valve |
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| US20020092573A1 (en) * | 1991-08-19 | 2002-07-18 | Harms Louis C. | Proportional pressure control valve |
| CN201209679Y (en) * | 2008-04-18 | 2009-03-18 | 山东泰丰液压设备有限公司 | Proportional guide servo control fully-active throttle cartridge valve |
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Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN102927074A (en) * | 2012-11-22 | 2013-02-13 | 兰州理工大学 | Anti-cavitation high frequency response and high flow proportional cartridge valve |
| CN102927074B (en) * | 2012-11-22 | 2016-12-21 | 兰州理工大学 | Anti-cavitation high frequency sound big flow proportional inserted valve |
| CN107654430A (en) * | 2017-09-29 | 2018-02-02 | 上海立新液压有限公司 | A kind of high frequency sound twin-stage proportional direction valve and its proportion directional control method |
| CN107725842A (en) * | 2017-11-08 | 2018-02-23 | 宁波文泽机电技术开发有限公司 | The ratio one-way flow valves of double-direction control |
| CN109854550A (en) * | 2017-11-30 | 2019-06-07 | 徐工集团工程机械股份有限公司科技分公司 | Hydraulic control system and engineering machinery |
| CN109854550B (en) * | 2017-11-30 | 2024-03-12 | 徐工集团工程机械股份有限公司科技分公司 | Hydraulic control system and engineering machinery |
| CN108757621A (en) * | 2018-08-14 | 2018-11-06 | 三河沃达液压控制***有限公司 | Indirect control formula digital servo valve |
| CN109372813A (en) * | 2018-11-30 | 2019-02-22 | 武汉船用机械有限责任公司 | A kind of electro-hydraulic proportional throttle valve and its control method |
| CN112576566A (en) * | 2020-12-07 | 2021-03-30 | 重庆红江机械有限责任公司 | Displacement feedback proportional flow control valve |
| CN113236623A (en) * | 2021-06-16 | 2021-08-10 | 太原理工大学 | Electro-hydraulic proportional direction valve with independently controlled valve port |
| CN114215924A (en) * | 2021-12-17 | 2022-03-22 | 油威力液压科技股份有限公司 | Pilot valve spool flat-turn combined special-shaped through-flow port large-flow cartridge valve |
| CN114215924B (en) * | 2021-12-17 | 2023-06-23 | 油威力液压科技股份有限公司 | Special-shaped through-flow port high-flow cartridge valve with pilot valve core combined in horizontal rotation mode |
| CN115095572A (en) * | 2022-07-21 | 2022-09-23 | 湖南十开科技有限公司 | Double-acting electro-hydraulic proportional push rod and electro-hydraulic proportional multi-way valve |
| CN115095572B (en) * | 2022-07-21 | 2024-05-28 | 湖南十开科技有限公司 | Double-acting electro-hydraulic proportional push rod and electro-hydraulic proportional multi-way valve |
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Application publication date: 20121121 |