CN101135326A - Giant-scale hydraulic press synchronous balancing hydraulic circuit - Google Patents
Giant-scale hydraulic press synchronous balancing hydraulic circuit Download PDFInfo
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- CN101135326A CN101135326A CNA2007100358149A CN200710035814A CN101135326A CN 101135326 A CN101135326 A CN 101135326A CN A2007100358149 A CNA2007100358149 A CN A2007100358149A CN 200710035814 A CN200710035814 A CN 200710035814A CN 101135326 A CN101135326 A CN 101135326A
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Abstract
The synchronous balancing hydraulic circuit comprises cartridge valve group, hydraulic-control check valve, ratio speed-regulation valve, ratio over-flow valve and high speed switch electromagnetic valve which can control the open and close of the cartridge valve group and is driven by a working controller to realize digital control. The oil supply pressure of the hydraulic-control check valve is provided from the main circuit, which can also be provided by other pressure sources. Advantages: reduced valve number of synchronous balancing hydraulic circuit of ten-thousand-ton grade hydraulic machine, high reliability, low cost, convenient maintenance, compact structure, reduced leakage and impaction to hydraulic system and raised precision.
Description
Technical field the present invention relates to a kind of ton hydraulic press that is used for material pressure processing, particularly relates to the ton hydraulic press synchronous balancing hydraulic circuit.
The existing ton hydraulic press synchronous balancing hydraulic circuit of background technique, the hydraulic element number of employing is many, cost height, maintenance inconvenience, reliability is low; When hydraulic press finished to carry out the off-load return in loading, moved cross beam simultaneous equation system was because the hydraulic control circuit response lag can produce bigger anti-drift angle, and existing oil hydraulic circuit can not in time be corrected, and has seriously restricted the raising of synchronization accuracy; Existing simultaneous equation oil hydraulic circuit speed of response still need improve.
Summary of the invention is in order to solve the above problem, a kind ofly can eliminate the simultaneous equation oil hydraulic circuit that synchronous hydraulic cylinder upper and lower cavity pressure reduction improves speed of response and synchronization accuracy can realize hydraulic differential and off-load return the time thereby the invention provides.The design loop has significantly reduced hydraulic element quantity, improves the response frequency and the reliability of system, has reduced cost, has also improved the automatization level and the synchronous control accuracy of ton hydraulic press synchronous balancing hydraulic system simultaneously.
The technical solution adopted for the present invention to solve the technical problems is:
Giant-scale hydraulic press synchronous balancing hydraulic circuit, thereby comprise the flow direction of controlling fluid and break-make decision correction direction, when needed can be with cartridge valve group (logical valve), the Pilot operated check valve of the locked formation locking system of synchronized cylinder, realize synchronized cylinder differential, accelerate correction speed of response proportional velocity regulating valve, system pressure is set up and proportional pressure control valve, the two-position three way high-speed switch electromagnetic valve of whether off-load;
Comprise concrete the composition: to the oil hydraulic pump 4 of synchronous hydraulic cylinder 13,14 supply pressure oil; Set up the system pressure and the proportional pressure control valve 5 of off-load whether with oil hydraulic pump 4 being used to of being connected in parallel; The proportional velocity regulating valve 8 that links to each other with oil hydraulic pump 4; Connect with proportional velocity regulating valve 8 by the cartridge valve valve group that cartridge valve 10,17 and solenoid valve 11,15 are formed; Interconnection is adopted in connection between the synchronous hydraulic cylinder 13,14, and promptly the epicoele of a certain synchronous hydraulic cylinder links to each other with the cavity of resorption of another synchronous hydraulic cylinder; Pilot operated check valve 12,16 upper ends link to each other with synchronous hydraulic cylinder 14 cavity of resorptions, and the lower end links to each other with solenoid valve 18 by oil pipe, and Pilot operated check valve 12,16 external control pressure oil-sources draw on automatic synchronization oil hydraulic cylinder 13 epicoeles and the oil circuit that synchronous hydraulic cylinder 14 cavity of resorptions link to each other; Pilot operated check valve 16 upper ends link to each other with synchronous hydraulic cylinder 14 cavity of resorptions, and the lower end links to each other with solenoid valve 19 by oil pipe, and Pilot operated check valve 16 external control pressure oil-sources draw on automatic synchronization oil hydraulic cylinder 13 cavity of resorptions and the oil circuit that synchronous hydraulic cylinder 14 epicoeles link to each other; Proportional velocity regulating valve 20 is connected in the neutral position of solenoid valve 18,19; Form secondary system draining backpressure regulation system by pilot operated compound relief valve 22, two-position two-way solenoid valve 23, relief valve 24, this system top is connected with proportional velocity regulating valve 20, and the bottom flows directly into fuel tank 25.
Oil hydraulic pump 4 is a variable displacement pump; The charge oil pressure of Pilot operated check valve 12,16 draws from major loop, also can provide by other pressure sources.
The opening and closing of the switch control cartridge valve 10,17 by control high-speed switch electromagnetic valve 11,15 adopt process control machine that high-speed switch electromagnetic valve is driven, and realize digital control.Valve 11,15 also can adopt general solenoid valve.
Electromagnet 1YA, 2YA by control electromagnetic valve 18,19 get electric or dead electricity, realize the synchronous off-load of synchronous hydraulic cylinder 13,14 and hydraulic press master clutch release slave cylinder.Electromagnet 1YA, 2YA by control electromagnetic valve 18,19 get electric or dead electricity, and in addition the cooperation of proportional flow control valve 20 can realize hydraulic differential, reach the purpose that improves speed of response.
Utilize the present invention can significantly reduce the quantity of ton hydraulic press synchronous balancing hydraulic circuit valve, reliability height, cost are low, easy to maintenance; Realize hydraulic differential, improved the speed of response of correction; The hydraulic system key component adopts cartridge valve, and compact and reasonable arrangement has reduced and leaked and loss, the impact that has alleviated hydraulic system simultaneously; Realize the synchronous off-load of synchronous hydraulic cylinder and main clutch release slave cylinder, thereby suppressed the generation of reverse deflection, improved synchronization accuracy greatly.
Description of drawings
Fig. 1: simultaneous equation oil hydraulic cylinder connection diagram;
Fig. 2: simultaneous equation oil hydraulic circuit fundamental diagram.
The present invention is further illustrated below in conjunction with accompanying drawing.
Embodiment
In four corners of hydraulic press a piston-type hydraulic cylinder (simultaneous equation cylinder) is set respectively, its cylinder body is fixed on the bottom end rail of hydraulic press, and piston rod is connected with the moved cross beam hinge property of hydraulic press.Four oil hydraulic cylinders are that a component is two groups by two of diagonal, the epicoele of a cylinder in every group is communicated with oil transport pipeline with the cavity of resorption of another cylinder, be four the chamber interconnections of two cylinders in every group of cylinder, a cornerwise levelness on every group of oil hydraulic cylinder control moved cross beam reference level.Specifically referring to Fig. 1.
Be the working principle that example illustrates giant-scale hydraulic press synchronous balancing hydraulic circuit with one group of simultaneous equation cylinder on the moved cross beam diagonal below, as shown in Figure 2, concrete working procedure is:
1, if the counterclockwise deflection of moved cross beam
Obviously, this moment, the simultaneous equation oil hydraulic circuit need be rectified a deviation to it.Left side oil hydraulic cylinder cavity of resorption among Fig. 2 and the right oil hydraulic cylinder epicoele oil-feed, left side oil hydraulic cylinder epicoele and the right oil hydraulic cylinder cavity of resorption oil return.
Control 3YA gets electric, the 4YA dead electricity, and cartridge valve 10 conductings this moment, cartridge valve 17 ends.Hydraulic oil enters left synchronous hydraulic cylinder lower end and right synchronous hydraulic cylinder upper end through proportional flow control valve 8 by cartridge valve 7, and oil is opened Pilot operated check valve 16 simultaneously; Synchronous hydraulic cylinder upper end, a left side and the lower end oil return of right synchronous hydraulic cylinder, 1YA, 2YA dead electricity, proportional flow control valve 20 is closed fully, and hydraulic oil backs down Pilot operated check valve 12 and mends the A point, realizes differentially, makes moved cross beam get back to horizontal position as early as possible.If do not needing under the differential situation, control 1YA gets electric, the 2YA dead electricity, and hydraulic oil then passes through Pilot operated check valve 16 through proportional flow control valve 20 oil sump tanks such as grade.Valve 22,23,24 is set up system's draining back pressure.
By changing the electric current of input proportional pressure control valve 5 proportion electro-magnets, the pressure of initialization system arbitrarily in rating value; When being zero, input current can make system unloaded.But, select for use to carry safety valve for preventing excessive fault current input to cause that too high pressure damages system.
2, if the clockwise deflection of moved cross beam
The right oil hydraulic cylinder cavity of resorption among Fig. 2 and left side oil hydraulic cylinder epicoele oil-feed, the right oil hydraulic cylinder epicoele and left side oil hydraulic cylinder cavity of resorption oil return.
Control 3YA dead electricity, 4YA gets electric, and this moment, cartridge valve 10 ended cartridge valve 17 conductings.Hydraulic oil enters right synchronous hydraulic cylinder lower end and left synchronous hydraulic cylinder upper end through proportional flow control valve 8 by cartridge valve 17, and oil is opened Pilot operated check valve 12 simultaneously; Right synchronous hydraulic cylinder upper end and the lower end oil return of left synchronous hydraulic cylinder, 1YA, 2YA dead electricity, proportional flow control valve 20 is closed fully, and hydraulic oil backs down Pilot operated check valve 16 and mends the B point, realizes differentially, makes moved cross beam get back to horizontal position as early as possible.If do not needing under the differential situation, control 1YA dead electricity, 2YA gets electric, and hydraulic oil then passes through Pilot operated check valve 12 through proportional flow control valve 20 oil sump tanks such as grade.
3, hydraulic press loads and finishes main clutch release slave cylinder off-load return
When hydraulic press finishes to carry out the off-load return in loading, the equal dead electricity of control 1YA, 2YA, this moment, the upper and lower chamber of two synchronous hydraulic cylinders was connected, pressure reduction, synchronous hydraulic cylinder and the synchronous off-load of hydraulic press master clutch release slave cylinder of elimination upper and lower cavity.
When 4, the moved cross beam angle of declination is in the margin of error that allows, control 3YA, 4YA dead electricity, cartridge valve 10,17 is all closed (ending), hydraulically-controlled one- way valve 12,16 is closed naturally simultaneously, make each chamber sealing of synchronous hydraulic cylinder, form locking system, making the electric current of input proportional pressure control valve 2 proportion electro-magnets simultaneously is zero, the oil hydraulic pump off-load.
Claims (3)
1. a hydraulic press synchronous balancing hydraulic circuit is characterized in that: comprise the oil hydraulic pump (4) to synchronous hydraulic cylinder (13,14) supply pressure oil; Set up the system pressure and the proportional pressure control valve (5) of off-load whether with oil hydraulic pump (4) being used to of being connected in parallel; The proportional velocity regulating valve 8 that links to each other with oil hydraulic pump (4); Connect with proportional velocity regulating valve 8 by the cartridge valve valve group that cartridge valve (10,17) and solenoid valve (11,15) are formed; Interconnection is adopted in connection between the synchronous hydraulic cylinder synchronous hydraulic cylinder (13,14), and promptly the epicoele of a certain synchronous hydraulic cylinder links to each other with the cavity of resorption of another synchronous hydraulic cylinder; Pilot operated check valve (12,16) upper end links to each other with synchronous hydraulic cylinder (14) cavity of resorption, the lower end links to each other with solenoid valve (18) by oil pipe, and Pilot operated check valve (12,16) external control pressure oil-source draws on automatic synchronization oil hydraulic cylinder (13) epicoele and the oil circuit that synchronous hydraulic cylinder (14) cavity of resorption links to each other; Pilot operated check valve (16) upper end links to each other with synchronous hydraulic cylinder (14) cavity of resorption, the lower end links to each other with solenoid valve (19) by oil pipe, and Pilot operated check valve (16) external control pressure oil-source draws on automatic synchronization oil hydraulic cylinder (13) cavity of resorption and the oil circuit that synchronous hydraulic cylinder (14) epicoele links to each other; Proportional velocity regulating valve (20) is connected in the neutral position of solenoid valve (18,19); Form secondary system draining backpressure regulation system by pilot operated compound relief valve (22), two-position two-way solenoid valve (23), relief valve (24), this system top is connected with proportional velocity regulating valve (20), and the bottom flows directly into fuel tank (25).
2. oil hydraulic circuit according to claim 1 is characterized in that: oil hydraulic pump (4) is a variable displacement pump.
3. oil hydraulic circuit according to claim 1 is characterized in that: adopt process control machine that high-speed switch electromagnetic valve is driven.
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CNB2007100358149A CN100482953C (en) | 2007-09-26 | 2007-09-26 | Giant-scale hydraulic press synchronous balancing hydraulic circuit |
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CNB2007100358149A CN100482953C (en) | 2007-09-26 | 2007-09-26 | Giant-scale hydraulic press synchronous balancing hydraulic circuit |
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CN101135326A true CN101135326A (en) | 2008-03-05 |
CN100482953C CN100482953C (en) | 2009-04-29 |
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Cited By (21)
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CN101982399A (en) * | 2010-09-01 | 2011-03-02 | 安徽天康(集团)股份有限公司 | Hydraulic lift independent iron tower rod differential superposition back-pressure hydraulic system |
CN101402263B (en) * | 2008-10-20 | 2011-05-04 | 江苏国力锻压机床有限公司 | Oil supply system for slide block and hydraulic pad of hydraulic press |
CN102336030A (en) * | 2011-10-13 | 2012-02-01 | 湖州机床厂有限公司 | Sliding block deviation correction mechanism of hydraulic press |
CN102430680A (en) * | 2011-10-25 | 2012-05-02 | 中南大学 | Super-slow hydraulic system for synchro-driven die-forging hydraulic press |
CN101644283B (en) * | 2009-08-31 | 2012-05-23 | 杭州电子科技大学 | Device used for studying synchronous driving performance |
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CN102836942A (en) * | 2012-09-24 | 2012-12-26 | 中南大学 | High-response hydraulic synchronizing circuit for compensating dead zone of hydraulic valve |
CN102886918A (en) * | 2012-10-24 | 2013-01-23 | 扬州捷迈锻压机械有限公司 | Wide-table-top hydraulic press closed-loop electrohydraulic control system with anti-eccentric load function |
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CN104912856A (en) * | 2015-06-16 | 2015-09-16 | 南通市腾达锻压机床厂 | Double oil cylinder synchronous servo control system device |
CN108533542A (en) * | 2018-04-09 | 2018-09-14 | 武汉科技大学 | A kind of deburring machine double-cylinder hydraulic synchronous control system |
CN109175188A (en) * | 2018-10-22 | 2019-01-11 | 中冶重工(唐山)有限公司 | Crankshaft forging press is bent mould oil cylinder synchronous unloading system and unloading method above and below |
CN110666851A (en) * | 2019-10-12 | 2020-01-10 | 盐城市智成机械制造有限公司 | Oil cylinder and guide post integrated soft material cutting machine |
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Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
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PT68274A (en) * | 1978-07-11 | 1978-08-01 | A A Ribeiro De Almeida | Device applicable to presses and metal bending presses to syncronize the movements of the hydraulic cylinders and control slider cross member |
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2007
- 2007-09-26 CN CNB2007100358149A patent/CN100482953C/en not_active Expired - Fee Related
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CN101644283B (en) * | 2009-08-31 | 2012-05-23 | 杭州电子科技大学 | Device used for studying synchronous driving performance |
CN101982399A (en) * | 2010-09-01 | 2011-03-02 | 安徽天康(集团)股份有限公司 | Hydraulic lift independent iron tower rod differential superposition back-pressure hydraulic system |
CN101982399B (en) * | 2010-09-01 | 2013-02-20 | 安徽天康(集团)股份有限公司 | Hydraulic lift independent iron tower rod differential superposition back-pressure hydraulic system |
CN101968067A (en) * | 2010-10-24 | 2011-02-09 | 绍兴市肯特机械电子有限公司 | High precision pump control system |
CN103597218A (en) * | 2011-06-09 | 2014-02-19 | 沃尔沃建造设备有限公司 | Hydraulic system for construction machinery |
CN102336030A (en) * | 2011-10-13 | 2012-02-01 | 湖州机床厂有限公司 | Sliding block deviation correction mechanism of hydraulic press |
CN102430680A (en) * | 2011-10-25 | 2012-05-02 | 中南大学 | Super-slow hydraulic system for synchro-driven die-forging hydraulic press |
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CN102705283A (en) * | 2012-05-29 | 2012-10-03 | 中南大学 | Hydraulic synchronous system for realizing load balance based on proportional relief valve |
CN102836942A (en) * | 2012-09-24 | 2012-12-26 | 中南大学 | High-response hydraulic synchronizing circuit for compensating dead zone of hydraulic valve |
CN102886918A (en) * | 2012-10-24 | 2013-01-23 | 扬州捷迈锻压机械有限公司 | Wide-table-top hydraulic press closed-loop electrohydraulic control system with anti-eccentric load function |
CN103671294A (en) * | 2013-12-12 | 2014-03-26 | 中联重科股份有限公司 | System and method for controlling synchronous rising and falling of suspension oil cylinders and engineering vehicle |
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CN104912856A (en) * | 2015-06-16 | 2015-09-16 | 南通市腾达锻压机床厂 | Double oil cylinder synchronous servo control system device |
CN108533542A (en) * | 2018-04-09 | 2018-09-14 | 武汉科技大学 | A kind of deburring machine double-cylinder hydraulic synchronous control system |
CN109175188A (en) * | 2018-10-22 | 2019-01-11 | 中冶重工(唐山)有限公司 | Crankshaft forging press is bent mould oil cylinder synchronous unloading system and unloading method above and below |
CN110666851A (en) * | 2019-10-12 | 2020-01-10 | 盐城市智成机械制造有限公司 | Oil cylinder and guide post integrated soft material cutting machine |
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