CN103438039A - Control method of self-reversing driving loop of synchronous cylinders - Google Patents
Control method of self-reversing driving loop of synchronous cylinders Download PDFInfo
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- CN103438039A CN103438039A CN2013104058717A CN201310405871A CN103438039A CN 103438039 A CN103438039 A CN 103438039A CN 2013104058717 A CN2013104058717 A CN 2013104058717A CN 201310405871 A CN201310405871 A CN 201310405871A CN 103438039 A CN103438039 A CN 103438039A
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Abstract
The invention discloses a control method of a self-reversing driving loop of synchronous cylinders in the field of hydraulic pressure industry. All chambers of a plurality of synchronous cylinders have the same symmetrical structures, and thus the oil cylinders are controlled to be synchronized by virtue of the same flow rate of left and right chambers of the synchronous cylinders and incompressible oil. A main loop of the self-reversing driving loop adopts a threaded cartridge valve with a conical sealing structure, and is assembled on one integration block to form a modular structure; a plurality of uniflow reversing modules can be stacked according to the synchronized flow number; each uniflow reversing module is provided with a pressure tap and a cartridge overflow valve is additionally arranged on each uniflow reversing module to make up the synchronization error of the synchronous cylinders and eliminate different inner leakages of an actuating oil cylinder; a system control loop is additionally provided with an energy accumulator, and a pilot control loop module of the self-reversing driving loop is provided with a mechanical limit module or an electro-hydraulic limit module. The control method can achieve self-reversing control on the synchronous cylinders, save the cost and reduce the energy consumption, and enables the synchronous cylinders with small specifications to drive the large actuating oil cylinder to move.
Description
Technical field
The present invention relates to a kind of application process for Hydraulic Industry, more particularly, the synchronized cylinder self-commutation that the present invention relates to a kind of multi-cylinder synchronous, precision Du Keda ± 0.1% working condition requirement drives the controlling method in loop.
Background technique
Last century end, multi-cylinder synchronous starts progressively to be applied to metallurgical grade for industry-by-industry.At present, synchronous kind mainly contains: mechanical synchronization, electric synchronization, hydraulic synchronization; Hydraulic synchronization can be realized the demand that power-weight ratio is high comparatively speaking.
Hydraulic synchronization comprises following several:
One, synchronous valve is synchronous.Its advantage has sexual valence higher, can realize that two cylinders are synchronous, is applicable to two cylinders and all carries synchronous requirement; Shortcoming has and generally is not used in the synchronous applications that is greater than two cylinders, and during unbalance loading, synchronization accuracy is minimum, generally in ± 10% left and right;
Two, Proportional valve electrichydraulic control loop is synchronous.Its advantage has automatically controlled program control oil cylinder synchronous, can realize closed loop control, and synchronization accuracy is higher, and can be with motion tracking; Shortcoming has the debugging more complicated, system fluid had relatively high expectations, and the automatical control system poor anti-interference, system throttling heating is higher, and cylinder movement speed is unsuitable too high, and synchronous fuel tank quantity is unsuitable too many, and cost performance is not high.
Three, flow control valve is synchronous.Its advantage has sexual valence higher, can realize multi-cylinder synchronous, is applicable to all carry the constant temperature occasion; Shortcoming has debug difficulties, needs band to carry debugging, and Security is not high, and the throttling heating is higher, influenced by ambient temperature, regularly finely tune, and now progressively eliminates.
Four, diffluence motor is synchronous.Its advantage has cost performance good, and product category is abundanter, can realize that the multi-cylinder unbalance loading is synchronous, and synchronization accuracy is higher generally in the scope (unbalance loading pressure is in the situation of 30bar left and right) of ± 0.5-± 2.5%; Shortcoming is subject to structural limitations, and synchronization accuracy is difficult to further improve, and for the highi degree of accuracy diffluence motor, its impact resistance is general, and in addition, its noise is higher.
Five, synchronized cylinder is synchronous.The tradition application, its advantage has synchronization accuracy high, can reach ± 0.07%, noise is low, is applied to multi-cylinder synchronous; Shortcoming has debug difficulties, and cost performance is general, and volume weight is huge, difficult in maintenance, and the pocketed oil chamber is arranged in the synchronized cylinder loop, needs regular topping up to change oil, and carries out in oil cylinder and lets out and have potential safety hazard.
In view of this, the invention provides the new application method of synchronized cylinder, promote cost performance, be easy to debugging, safeguard, solve the synchronized cylinder entrap phenomenon, stop potential safety hazard, obtain higher synchronization accuracy, generally in ± 0.2% left and right.The new selection of hydraulic synchronization is provided simultaneously, meets the hydraulic synchronization requirements for high precision.
Summary of the invention
The objective of the invention is to overcome the shortcoming of synchronized cylinder tradition application, main cause is that synchronized cylinder directly links together with the execution oil cylinder, form the pocketed oil chamber of a sealing, carry out transmitted power by fluid, synchronized cylinder is when carrying out the oil cylinder unidirectional movement, can only be in unidirectional direction motion, therefore, the volume of effective cavity volume of synchronized cylinder must be larger than the volume of effective cavity volume of carrying out oil cylinder.For this reason, the invention provides the controlling method that a kind of synchronized cylinder self-commutation that can overcome above-mentioned prior art deficiency drives loop.
The objective of the invention is to be achieved through the following technical solutions:
A kind of synchronized cylinder self-commutation drives the controlling method in loop, and the concrete steps of this method are as follows:
A. each cavity volume of many synchronized cylinders adopts identical symplex structure, according to synchronized cylinder left and right two chamber flows are identical, with incompressibility principle fluid, control and carries out the oil cylinder synchronization motion;
B. self-commutation drives the synchronization error that the major loop in loop adopts the screw-in cartridge valve of cone-shaped seal structure to bring to reduce commutation, can reduce the energy consumption of system simultaneously.
C. according to the traffic demand of carrying out oil cylinder, the pressure loss of screw-in cartridge valve is no more than 2bar, and in order to obtain rapid response speed, the turn around time of screw-in cartridge valve must be lower than 25ms,
D. the single current inverting module adopts 5 screw-in cartridge valves, comprising 4 2/2-way selector valves and 1 relief valve collection, is contained on an integrated package, forms modular organization;
E. according to synchronous fluxion, stackable a plurality of single current inverting modules;
F. the single current inverting module is provided with pressure tap, for debugging, malfunction alarm and maintenance;
G. set up plug-in overflow valve on the single current inverting module, the adjusting pressure of relief valve, higher than carrying out the actual working pressure 10bar of oil cylinder, is carried out the impact of letting out in the oil cylinder difference for the synchronization error and the elimination that make up synchronized cylinder;
H. drive flow and the pressure surge of loop switch in order to reduce self-commutation, the system control loop is set up accumulator, and the volume that the size of accumulator is controlled cavity volume according to screw-in cartridge valve is determined, and the upper limit is no more than 1L;
Purpose of the present invention can also be achieved through the following technical solutions:
Described self-commutation drives the pilot control return circuit module in loop to be provided with mechanical position limitation module or electric liquid limit position module.Described mechanical position limitation module is provided with the elements such as 3-position 4-way servomotor driven change valve, hydraulic lock, plug-in type zero-leakage valve and mechanical collision block and forms.Described electric liquid limit position module is provided with limit switch, two elements such as four-way electromagnetic reversing valve, plug-in type zero-leakage valve and PLC form.The commutation entrance of described plug-in type zero-leakage valve is connected with A, the B mouth of system control loop respectively, and the size of plug-in type zero-leakage valve drives the control flow of loop major loop to determine according to self-commutation, and the single current instantaneous flow is no more than 20L/min.
Compared with prior art, the present invention has following beneficial effect:
The present invention is by change synchronized cylinder using method, reaching the synchronized cylinder self-commutation controls, can realize driving the large purpose of carrying out cylinder movement with the small dimension synchronized cylinder, cost-saving, reduce energy consumption, be easy to debugging, safeguard, can solve the applications such as the metallurgy industry cold bed is synchronous, hydropower industry cylinder valve is synchronous highi degree of accuracy, high capacity disequilibrium problem, improve the durability requirements of synchro system.
The accompanying drawing explanation
Fig. 1 is that the synchronized cylinder self-commutation drives the controlling method in loop (to contain: mechanical position limitation module pilot control loop) schematic diagram;
Fig. 2 is that the synchronized cylinder self-commutation drives the controlling method in loop (to contain: module pilot control loop, electric liquid limit position) schematic diagram.
In figure: synchronized cylinder 1, screw-in cartridge valve (2/2-way selector valve) 2, single current inverting module 3, plug-in overflow valve 4, execution oil cylinder 5, system control loop 6, accumulator 7, mechanical position limitation module (pilot control loop) 8, plug-in type zero-leakage valve 9,3-position 4-way servomotor driven change valve 10, hydraulic lock 11, mechanical collision block 12,13, two four-way electromagnetic reversing valves 14 of electric liquid limit position module (pilot control loop), limit switch 15.
Embodiment
Below in conjunction with drawings and Examples, the essence of an invention content is described in further detail:
As depicted in figs. 1 and 2: each cavity volume of a plurality of synchronized cylinders 1 is all identical symplex structure, control loop can be controlled for the Huo You chamber, left chamber of synchronized cylinder 1, the synchronization error that self-commutation drives the major loop in loop to adopt screw-in cartridge valve 2 forms of 4 cone-shaped seal structures to bring to reduce commutation, simultaneously in order to reduce the energy consumption of system, screw-in cartridge valve 2 is according to the traffic demand of carrying out oil cylinder 5, its pressure loss is no more than 2bar, in order to obtain rapid response speed, screw-in cartridge valve 2 turn around time General Requirements lower than 25ms; In order to obtain modular organization, adopt 4 screw-in cartridge valves 2 and 1 plug-in overflow valve 4 collection to be contained on an integrated package and form 1 single current inverting module; According to synchronous fluxion, stackable a plurality of single current inverting modules 3; In order to meet debugging, malfunction alarm, maintenance requirement, each single current inverting module 3 is with a pressure tap.
In order to make up the synchronization error of synchronized cylinder 1, or let out in order to eliminate in the difference of carrying out oil cylinder 5, set up plug-in overflow valve 4 on single current inverting module 3, when 5 motions of execution oil cylinder put in place, unnecessary fluid flows to fuel tank from plug-in overflow valve 4, the journey error of carrying out 5 of oil cylinders to eliminate each, the adjusting pressure of plug-in overflow valve 4 is higher than carrying out the actual working pressure 10bar of oil cylinder 5 left and right.
Self-commutation drives the pilot control loop in loop can adopt the method for mechanical position limitation module 8 or electric liquid limit position module 13, and mechanical position limitation module 8 consists of elements such as 3-position 4-way servomotor driven change valve 10, hydraulic lock 11, plug-in type zero-leakage valve 9, mechanical collision blocks 12; Electricity liquid limit position module 13 adopts the elements such as limit switch 15, two four-way electromagnetic reversing valves 14, plug-in type zero-leakage valve 9, PLC to form.For fear of synchronized cylinder 1 condition of commutation caused due to 5 commutations of execution oil cylinder, self-commutation drives the plug-in type zero-leakage valve 9 commutation entrances in the pilot control loop in loop to be connected with A, the B mouth of system control loop 6 respectively.The size of plug-in type zero-leakage valve drives the control flow of loop major loop to determine according to self-commutation, and generally, the single current instantaneous flow is no more than 20L/min, annotates: the fluid volume of its actual use is also little.
Drive flow and the pressure surge of loop switch in order to reduce self-commutation, the system control loop set up accumulator 7, the volume that the size of accumulator 7 is controlled cavity volumes according to screw-in cartridge valve 2 is determined, and generally is no more than 1L.The pressure surge explanation of synchronized cylinder 1 handoff procedure: due to the pressure difference between two chambeies, synchronized cylinder 1 left and right, there is the pressure surge of about 5bar in the system switching, can be sponged by the accumulator 7 of system control loop.
Embodiment one (four streams of take are synchronously example, as shown in Figure 1): by mechanical position limitation module 8, four single current inverting modules 3, system control loop 6(, contained: accumulator 7), four carry out oil cylinders 5 etc. and form.Synchronized cylinder 1 adopts Φ 80/ Φ 40-100(piston diameter 80mm, diameter of piston rod 40mm, stroke 100mm), hydraulic fluid port employing G3/4 "; maximum movement speed 0.3m/s, single current flow: 0～70L/min, total tetra-the left chambeies of A1～A4 of synchronized cylinder 1 and tetra-right chambeies of B1～B4; pipeline adopts DN15, total discharge scope: 0～280L/min;
Single current inverting module 3, screw-in cartridge valve 2 is selected the LOHC series cartridge valve of SUN, during flow 70L/min, pressure reduction is in about 1bar, and the valve group is less than 25ms switching time, when imperial palace is let out 1.2cc/min(oil viscosity 24cSt, measures), single current inverting module 3 is controlled fluid instantaneous flow: 20L/min, the required oil mass 8.2ml of single current, four stream required master control flow: 80L/min, the required control oil mass 32.8mL of four stream, can determine that according to this flow self-commutation drives the parameter of plug-in type zero-leakage valve 9 in the pilot control loop in loop, consider the impact of crushing on single current inverting module 3, select the LOFC plug-in type zero-leakage valve of crushing in the 3bar left and right, consider the characteristics of 3-position 4-way servomotor driven change valve 10, working stroke is at 2.8mm, switch speed is determined by synchronized cylinder 1, according to geometrical property while spending (track slope of collision block be 20), be 25.7ms the switching time of known 3-position 4-way servomotor driven change valve 10, it is 5.1L/min that self-commutation drives the control flow in the pilot control loop in loop, select the latus rectum DN6 of 3-position 4-way servomotor driven change valve 10.The total measurement (volume) of the mechanical position limitation module 8 required fluid in four single current inverting modules 3 and a pilot control loop is 35ml, and the accumulator 7 actual volume 0.4L of selective system control loop get final product, and inflation pressure 0.9P1(P1 is the required pressure minimum of system).
The control loop of the mechanical position limitation module 8 in pilot control loop is controlled by 3-position 4-way servomotor driven change valve 10 and hydraulic lock 11, controls fluid and derives from the pressure oil circuit of system or the pilot pressure oil circuit of system.When the limit position of mechanical collision block 12,3-position 4-way servomotor driven change valve 10 is in the two ends commutation states, control fluid and control plug-in type zero-leakage valve 9 switchings of this module through 3-position 4-way servomotor driven change valve 10, the commutation entrance of plug-in type zero-leakage valve 9, outlet are connected in the oil circuit control of A, B mouth and the single current inverting module 3 of system control loop 6.3-position 4-way servomotor driven change valve 10 is when two ultimate states, the fluid of system enters the plug-in type zero-leakage valve 9 of mechanical position limitation module 8 and the screw-in cartridge valve 2 pilot cavity volumes of single current inverting module 3 through A, B mouth, to control synchronized cylinder 1 commutation, but when synchronized cylinder 1 leaves limit position, 3-position 4-way servomotor driven change valve 10 switches to meta, plug-in type zero-leakage valve 9 states of hydraulic lock locking mechanical position limitation module 8, thus guarantee that synchronized cylinder 1 continues motion in set moving direction; When system is carried out oil cylinder 5 commutation, because the plug-in type zero-leakage valve 9 of mechanical position limitation module 8 is connected with A, the B mouth of system control loop 6, so the moving direction of synchronized cylinder 1 can not change.
In order to guarantee normal commutation, the Area Ratio of screw-in cartridge valve 2 and plug-in type zero-leakage valve 9 should not have big difference, generally between 1:2 or 1:1.8.
(four streams of take are synchronously example to embodiment two, as shown in Figure 2): electric liquid limit position module 13, single current inverting module 3, system control loop 6, accumulator 7, execution oil cylinder 5 etc., consist of.The method and embodiment one are basic identical, change place: mechanical position limitation module 8 is changed to electric liquid limit position module 13.
Electricity liquid limit position module 13, mainly by electrical signal as feedback sources, two four-way electromagnetic reversing valves, as hydraulic control component, realize controlling purpose by PLC or analog circut.It is faster that the advantage of electricity liquid limit position module 13 is to control turn around time, can reach the 15ms left and right, can regulate the commutation stroke of synchronized cylinder 1 by the position of regulating limit switch 15, shortcoming: needing increases electronic control module, and anti-electromagnetic interference is slightly poor.
When synchronized cylinder 1 triggers limit switch 15, two four-way electromagnetic reversing valves 14 are switched to another limit position, carry out oil cylinder 5 and move while putting in place, and two four-way electromagnetic reversing valves 14 keep these states.When execution oil cylinder 5 commutates again, synchronized cylinder 1 is according to original direction motion.
Claims (5)
1. a synchronized cylinder self-commutation drives the controlling method in loop, it is characterized in that: the concrete steps of this method are as follows: by a plurality of synchronized cylinders, combined, the cavity volume of each synchronized cylinder adopts identical symplex structure, synchronized cylinder left and right two chamber flows are identical, fluid is incompressible, in order to control, carries out the oil cylinder synchronization motion; Self-commutation drives the major loop in loop to adopt the screw-in cartridge valve of cone-shaped seal structure; According to the traffic demand of carrying out oil cylinder, the pressure loss of screw-in cartridge valve is no more than 2bar, and the turn around time of screw-in cartridge valve must be lower than 25ms; The single current inverting module adopts 5 screw-in cartridge valves, comprising 4 2/2-way selector valves and 1 relief valve collection, is contained on an integrated package, forms modular organization; According to the fluxion of synchronized cylinder, stackable a plurality of single current inverting modules; The single current inverting module is provided with pressure tap, for debugging, malfunction alarm and maintenance; Set up plug-in overflow valve on the single current inverting module, the adjusting pressure of relief valve, higher than carrying out the actual working pressure 10bar of oil cylinder, is carried out the impact of letting out in the oil cylinder difference in order to the synchronization error and the elimination that make up synchronized cylinder; Drive flow and the pressure surge of loop switch in order to reduce self-commutation, the system control loop is set up accumulator, and the volume that the size of accumulator is controlled cavity volume according to screw-in cartridge valve is determined, and the upper limit is no more than 1L.
2. a kind of synchronized cylinder self-commutation according to claim 1 drives the controlling method in loop, it is characterized in that: described self-commutation drives the pilot control return circuit module in loop to be provided with mechanical position limitation module or electric liquid limit position module.
3. a kind of synchronized cylinder self-commutation according to claim 2 drives the controlling method in loop, it is characterized in that: described mechanical position limitation module is provided with the elements such as 3-position 4-way servomotor driven change valve, hydraulic lock, plug-in type zero-leakage valve and mechanical collision block and forms.
4. a kind of synchronized cylinder self-commutation according to claim 2 drives the controlling method in loop, it is characterized in that: described electric liquid limit position module is provided with limit switch, two elements such as four-way electromagnetic reversing valve, plug-in type zero-leakage valve and PLC form.
5. a kind of synchronized cylinder self-commutation according to claim 1 drives the controlling method in loop, it is characterized in that: the commutation entrance of described plug-in type zero-leakage valve is connected with A, the B mouth of system control loop respectively, the size of plug-in type zero-leakage valve drives the control flow of loop major loop to determine according to self-commutation, and the single current instantaneous flow is no more than 20L/min.
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| CN201310405871.7A CN103438039B (en) | 2013-09-09 | 2013-09-09 | Control method of self-reversing driving loop of synchronous cylinders |
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
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| JP2005214368A (en) * | 2004-02-02 | 2005-08-11 | Takenaka Komuten Co Ltd | Hydraulic circuit |
| US7603942B1 (en) * | 2006-09-29 | 2009-10-20 | Hwh Corporation | Synchronization cylinder having chambers with different volumes |
| WO2009141697A1 (en) * | 2008-05-20 | 2009-11-26 | Valtra Oy Ab | Hydraulic actuation system with multi piston actuator |
| CN102116326A (en) * | 2011-02-23 | 2011-07-06 | 周建新 | Hydraulic push-pull synchronization method and device thereof |
| CN201925253U (en) * | 2011-02-23 | 2011-08-10 | 周建新 | Device used for realizing hydraulic push-pull synchronization |
| CN102434511A (en) * | 2011-11-22 | 2012-05-02 | 江苏龙城洪力液压设备有限公司 | Multiple-cylinder synchronous hydraulic system |
| CN103089725A (en) * | 2011-10-27 | 2013-05-08 | 泊姆克(天津)液压有限公司 | Two-way plug-in mounting vibrating valve and electric hydraulic control unit |
-
2013
- 2013-09-09 CN CN201310405871.7A patent/CN103438039B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005214368A (en) * | 2004-02-02 | 2005-08-11 | Takenaka Komuten Co Ltd | Hydraulic circuit |
| US7603942B1 (en) * | 2006-09-29 | 2009-10-20 | Hwh Corporation | Synchronization cylinder having chambers with different volumes |
| WO2009141697A1 (en) * | 2008-05-20 | 2009-11-26 | Valtra Oy Ab | Hydraulic actuation system with multi piston actuator |
| CN102116326A (en) * | 2011-02-23 | 2011-07-06 | 周建新 | Hydraulic push-pull synchronization method and device thereof |
| CN201925253U (en) * | 2011-02-23 | 2011-08-10 | 周建新 | Device used for realizing hydraulic push-pull synchronization |
| CN103089725A (en) * | 2011-10-27 | 2013-05-08 | 泊姆克(天津)液压有限公司 | Two-way plug-in mounting vibrating valve and electric hydraulic control unit |
| CN102434511A (en) * | 2011-11-22 | 2012-05-02 | 江苏龙城洪力液压设备有限公司 | Multiple-cylinder synchronous hydraulic system |
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