CN106438520A - Cooling bed lifting hydraulic synchronous control device - Google Patents
Cooling bed lifting hydraulic synchronous control device Download PDFInfo
- Publication number
- CN106438520A CN106438520A CN201611171340.6A CN201611171340A CN106438520A CN 106438520 A CN106438520 A CN 106438520A CN 201611171340 A CN201611171340 A CN 201611171340A CN 106438520 A CN106438520 A CN 106438520A
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- China
- Prior art keywords
- valve
- proportional direction
- cold bed
- hydraulic
- direction valve
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
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Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B9/00—Servomotors with follow-up action, e.g. obtained by feed-back control, i.e. in which the position of the actuated member conforms with that of the controlling member
- F15B9/02—Servomotors with follow-up action, e.g. obtained by feed-back control, i.e. in which the position of the actuated member conforms with that of the controlling member with servomotors of the reciprocatable or oscillatable type
- F15B9/08—Servomotors with follow-up action, e.g. obtained by feed-back control, i.e. in which the position of the actuated member conforms with that of the controlling member with servomotors of the reciprocatable or oscillatable type controlled by valves affecting the fluid feed or the fluid outlet of the servomotor
- F15B9/09—Servomotors with follow-up action, e.g. obtained by feed-back control, i.e. in which the position of the actuated member conforms with that of the controlling member with servomotors of the reciprocatable or oscillatable type controlled by valves affecting the fluid feed or the fluid outlet of the servomotor with electrical control means
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B43/00—Cooling beds, whether stationary or moving; Means specially associated with cooling beds, e.g. for braking work or for transferring it to or from the bed
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B13/00—Details of servomotor systems ; Valves for servomotor systems
- F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
- F15B13/06—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with two or more servomotors
- F15B13/08—Assemblies of units, each for the control of a single servomotor only
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B13/00—Details of servomotor systems ; Valves for servomotor systems
- F15B13/16—Special measures for feedback, e.g. by a follow-up device
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- General Engineering & Computer Science (AREA)
- Fluid-Pressure Circuits (AREA)
Abstract
The invention discloses a cooling bed lifting hydraulic synchronous control device. The device comprises a plurality of proportional direction valves arranged on hydraulic valve stand beside a cooling bed in parallel, an electromagnetic reversing valve and a hydraulic control check valve are arranged on a communication pipeline of the proportional direction valves and hydraulic oil, an oil outlet pipeline of each proportional direction valve is further connected with a servo hydraulic cylinder, displacement sensors serving as external displacement sensors are arranged on the servo hydraulic cylinders, the displacement sensors are also connected with the proportional direction valves, and the proportional direction valves and the displacement sensors form position closed loops. Closed-loop control precision of cooling bed lifting hydraulic synchronous control can reach +/-1 mm; compared with existing cooling bed lifting control schemes, synchronous control precision is very high, and synchronous control precision can also be guaranteed especially when unbalance loading of the cooling bed is large; by setting a curve of proportional direction valve control signals, stable start and shutdown are easy to achieve, and quick lifting operation is achieved.
Description
Technical field
The invention belongs to technical field of metallurgical equipment, is related to a kind of cold bed raise-lower hydraulic sync control device.
Background technology
One of visual plant on the cold bed side of being (circle) billet continuous casting machine production line, in order to ensure the cooling quality of strand, typically
Walking beam cooler is all adopted;By lifting and the reciprocating motion of bed surface itself, strand is made to be gradually cooled as it passes through the cooler during traversing.By
It is cut into, in strand, the length that 6m~12m is not waited as needed, which increases the unbalance loading degree in cold bed lifting running;
Just start production in casting machine, the strand on cold bed is gradually increased, and the load of cold bed is gradually increased cold bed side from strand, or terminate
The gradually decreasing of cold bed strand during production, the load of cold bed is gradually reduced cold bed side from strand, both increases the unbalance loading of cold bed
Degree, increased the difficulty of cold bed synchronous operation control.
Conventional cold bed lifting generally adopts following 3 kinds of modes:Mechanical synchronization, solenoid directional control valve add one-way throttle valve, ratio
Proportional direction valve adds syncmotor, all exist that equipment quality is big, synchronization accuracy is poor, bumpy motion a series of problems, such as.Such as cold
Bed lifting adopts mechanical synchronization, and 4 lifting hydraulic cylinders realize cold bed lifting action by driving crank connecting link reciprocally swinging, due to
Cold bed load is big, unbalance loading big, and crank connecting link is connected on same axis, so connecting shaft and bearing must sufficiently large, Cai Nengbao
The enough rigidity of card, it is ensured that the synchronization of cold bed lifting, so equipment quality is big, investment is big.As cold bed lifting adopts electromagnetic switch
Valve adds one-way throttle valve, and 4 lifting hydraulic cylinders are synchronous by 4 solenoid directional control valves and 4 one-way throttle valve controls respectively, cold
When bed unbalance loading is larger, one-way throttle valve control net synchronization capability is excessively poor, and operational shock is big, easily causes cold bed motion uneven
The deformation of steady and cold bed bed body.As cold bed lifting adoption rate direction valve adds syncmotor, 4 lifting hydraulic cylinders are compared by 1
Proportional direction valve and 1 syncmotor control are synchronous, and when cold bed unbalance loading is larger, synchronization accuracy declines, and cold bed is with casting machine pulling rate
Raising, running frequency progressively accelerates, and the frequency of the positive and negative operating switching of syncmotor is also accelerated, and reduces the use longevity of motor
Life, and syncmotor itself pressure drop is larger, easily causes Hydraulic System Fever.
Content of the invention
Object of the present invention is to provide a kind of device of cold bed raise-lower hydraulic Synchronization Control, the device can passing ratio
Displacement transducer composition position closed loop on direction valve and cold bed lift servo hydraulic cylinder, realizes the flat of cold bed by electrical control
Surely, quick lifting action.
The present invention is to be achieved through the following technical solutions:
A kind of cold bed raise-lower hydraulic sync control device, including some ratios being arranged in parallel on the other hydraulic valve platform of cold bed
Direction valve, is additionally provided with solenoid directional control valve and hydraulic control one-way valve on connecting pipeline of the proportional direction valve with hydraulic oil, each ratio
Servo hydraulic cylinder is also associated with the outlet line of direction valve, and displacement transducer is arranged on servo as external displacement transducer
On hydraulic cylinder, displacement transducer is also connected with proportional direction valve, and proportional direction valve constitutes position closed loop with displacement transducer.
Described solenoid directional control valve controls the fuel feeding of each proportional direction valve by hydraulic control one-way valve;Proportional direction valve is pressed
Control the raising and lowering action of coupled servo hydraulic cylinder respectively according to the signal for setting.
In servo hydraulic cylinder running, displacement transducer carries out real-time detection to which, and to being input into proportional direction valve
Signal fed back, realize the synchronous operation of lift servo hydraulic cylinder.
When the displacement that displacement transducer detects servo hydraulic cylinder reality exceedes threshold value with the displacement deviation for setting,
The fuel feeding of solenoid directional control valve cut-out proportional direction valve, stops the operation of cold bed.
By the control signal of setting ratio direction valve or the curve of current signal, servo hydraulic cylinder is driven according to smooth
Rate curve runs.
Described proportional direction valve is four and is arranged in parallel, and controls a servo hydraulic cylinder respectively per platform proportional direction valve
Raising and lowering.
Compared with prior art, the present invention has following beneficial technique effect:
The cold bed raise-lower hydraulic sync control device that the present invention is provided, passing ratio direction valve constitutes position with displacement transducer
Closed loop is put, the synchronization lifting of multiple stage servo hydraulic cylinder can be realized so that the closed-loop control precision of cold bed lifting Synchronization Control can
Reach ± 1mm, more conventional cold bed elevating control scheme, synchronous control accuracy is very high, especially cold bed in unbalance loading larger when,
Synchronous control accuracy also can guarantee that;Curve by setting ratio direction valve control signal (current signal), it is easy to realize flat
Steady start and stop, fast lifting runs.
The cold bed raise-lower hydraulic sync control device that the present invention is provided, adoption rate direction valve constitutes position with displacement transducer
Put closed loop, lifting synchronous control accuracy height;It is particularly suitable for cold bed synchronization lifting operation under the larger operating mode of unbalance loading;In cold bed synchronization
When liter or decline operation are overproof, can stop immediately, to equipment, there is safety protection function.
The cold bed raise-lower hydraulic sync control device that the present invention is provided, proportional direction valve valve port pressuring drop is little, and system heat generation is little;
Cold bed lifting can be run according to set rising or falling speed, not only steadily but also quick, the lifting circulating of suitable cold bed bed surface high frequency
OK;Proportional direction valve contamination resistance is strong, less demanding to Hydraulic system cleanliness;Displacement transducer adopts digital signal, resists
Interference;Whole cold bed lift control system is simple, reliable.
Description of the drawings
Fig. 1 is schematic structural view of the invention.
In figure:1 is solenoid directional control valve;2 is hydraulic control one-way valve;3 is proportional direction valve;4 is servo hydraulic cylinder;5 is displacement
Sensor.P is pressure oil pipeline, and T is return line, L for revealing oil pipe line.
Specific embodiment
With reference to specific embodiment, the present invention is described in further detail, described be explanation of the invention and
It is not to limit.
Referring to Fig. 1, a kind of cold bed raise-lower hydraulic sync control device, including being arranged in parallel on the other hydraulic valve platform of cold bed
Some proportional direction valves 3, are additionally provided with solenoid directional control valve 1 and fluid-control one-way on connecting pipeline of the proportional direction valve 3 with hydraulic oil
Valve 2, is also associated with servo hydraulic cylinder 4 in the outlet line of each proportional direction valve 3, displacement transducer 5 is used as external displacement
Sensor is arranged on servo hydraulic cylinder 4, and displacement transducer 5 is also connected with proportional direction valve 3, proportional direction valve 3 and displacement
Sensor 5 constitutes position closed loop.
Wherein, described solenoid directional control valve 1 controls the fuel feeding of each proportional direction valve 3 by hydraulic control one-way valve 2;Ratio
Direction valve 3 controls the raising and lowering action of coupled servo hydraulic cylinder 4 respectively according to the signal for setting.
In 4 running of servo hydraulic cylinder, displacement transducer 5 carries out real-time detection to which, and to being input into proportion directional
The signal of valve 3 is fed back, and realizes the synchronous operation of lift servo hydraulic cylinder 4.
When the displacement deviation that displacement transducer detects the displacement of 4 reality of servo hydraulic cylinder and setting exceedes threshold value
When, solenoid directional control valve 1 cuts off the fuel feeding of proportional direction valve 3, stops the operation of cold bed.
By the control signal of setting ratio direction valve 3 or the curve of current signal, servo hydraulic cylinder 4 is driven according to smooth
Rate curve operation.
Specific embodiment is given below.
Referring to Fig. 1, a kind of cold bed raise-lower hydraulic sync control device, including:1, hydraulic control one-way valve of solenoid directional control valve
2nd, 4 displacement transducers 5 of servo hydraulic cylinder 4,4 of proportional direction valve 3,4.Solenoid directional control valve 1, hydraulic control one-way valve 2, ratio side
To valve 3 on the other hydraulic valve platform of cold bed;4 displacement transducers 5 are separately mounted on 4 servo hydraulic cylinders 4, and formation is watched
Take external hydraulic cylinder displacement transducer.
Solenoid directional control valve 1 controls the fuel feeding of each proportional direction valve 3 by hydraulic control one-way valve 2;Proportional direction valve 3 is respectively
The raising and lowering action of control servo hydraulic cylinder 4;Proportional direction valve 3 constitutes position closed loop with displacement transducer 5, realizes cold bed
Not only steady but also quick lifting action.
Automatically controlled 3 control signal of setting ratio direction valve, realizes cold bed lift servo hydraulic cylinder according to smooth rate curve
Operation, it is steady during starting or stoping that cold bed lifting is easily achieved cold bed, no impacts, fast in middle running
Quick-action is made.In cold bed lifting hydraulic cylinder running, displacement transducer carries out real-time detection, and to being input into proportional direction valve
Signal is fed back, and realizes the synchronous operation of 4 lift servo hydraulic cylinders.
The position of servo hydraulic cylinder reality when proportional direction valve is out of control or closed loop is unstable, is detected by displacement transducer
The fuel feeding of proportional direction valve when shifting amount exceedes setting value with the displacement deviation for setting, can be cut off by solenoid directional control valve, stopped
The only operation of cold bed, will not cause to damage to cooling bed device.
In cold bed running, proportional direction valve itself valve port pressuring drop is little, and system heat generation is little;Cold bed lifting can be according to
Set rising or falling speed operation, both steadily by quick, the lifting circular flow of suitable cold bed bed surface high frequency;Proportional direction valve anti-soil
Dye ability is strong, less demanding to Hydraulic system cleanliness;Displacement transducer adopts digital signal, anti-interference;Whole cold bed lifting
Control system is simple, reliable.
Example given above is to realize the present invention preferably example, the invention is not restricted to above-described embodiment.This area
Technical staff made according to the technical characteristic of technical solution of the present invention any nonessential interpolation, replacement, belong to this
The protection domain of invention.
Claims (6)
1. a kind of cold bed raise-lower hydraulic sync control device, it is characterised in that including being arranged in parallel on the other hydraulic valve platform of cold bed
Some proportional direction valves (3), be additionally provided with the connecting pipeline of proportional direction valve (3) and hydraulic oil solenoid directional control valve (1) and
Hydraulic control one-way valve (2), is also associated with servo hydraulic cylinder (4), displacement transducer in the outlet line of each proportional direction valve (3)
(5) be arranged on servo hydraulic cylinder (4) as external displacement transducer, displacement transducer (5) also with proportional direction valve (3) phase
Connection, proportional direction valve (3) constitutes position closed loop with displacement transducer (5).
2. cold bed raise-lower hydraulic sync control device as claimed in claim 1, it is characterised in that described solenoid directional control valve
(1) fuel feeding of each proportional direction valve (3) is controlled by hydraulic control one-way valve (2);Proportional direction valve (3) is according to the signal for setting
Control the raising and lowering action of coupled servo hydraulic cylinder (4) respectively.
3. cold bed raise-lower hydraulic sync control device as claimed in claim 1, it is characterised in that transport in servo hydraulic cylinder (4)
During row, displacement transducer (5) carries out real-time detection to which, and the signal for being input into proportional direction valve (3) is fed back, real
The synchronous operation of existing lift servo hydraulic cylinder (4).
4. the cold bed raise-lower hydraulic sync control device as described in claim 1 or 3, it is characterised in that when displacement transducer is examined
When the displacement deviation of the displacement and setting that measure servo hydraulic cylinder (4) reality exceedes threshold value, solenoid directional control valve (1) cut-out ratio
The fuel feeding of proportional direction valve (3), stops the operation of cold bed.
5. the cold bed raise-lower hydraulic sync control device as described in claim 1 or 3, it is characterised in that by setting ratio side
To the control signal of valve (3) or the curve of current signal, servo hydraulic cylinder (4) is driven to run according to smooth rate curve.
6. cold bed raise-lower hydraulic sync control device as claimed in claim 1, it is characterised in that described proportional direction valve
(3) it is four to be arranged in parallel, controls the raising and lowering of a servo hydraulic cylinder (4) per platform proportional direction valve (3) respectively.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
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CN201611171340.6A CN106438520A (en) | 2016-12-17 | 2016-12-17 | Cooling bed lifting hydraulic synchronous control device |
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CN201611171340.6A CN106438520A (en) | 2016-12-17 | 2016-12-17 | Cooling bed lifting hydraulic synchronous control device |
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CN106438520A true CN106438520A (en) | 2017-02-22 |
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ID=58216615
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CN201611171340.6A Pending CN106438520A (en) | 2016-12-17 | 2016-12-17 | Cooling bed lifting hydraulic synchronous control device |
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Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN109915628A (en) * | 2019-03-07 | 2019-06-21 | 深圳市华腾精密机械有限公司 | The integrated inserting valve group in water route and vulcanization mechanomotive force water system |
CN109973471A (en) * | 2019-04-11 | 2019-07-05 | 南通大学 | A kind of more fulcrum synchronisation control means of large size hoistable platform and control system |
CN110886732A (en) * | 2019-12-10 | 2020-03-17 | 北京北特圣迪科技发展有限公司 | PLC-based multi-stage multi-cylinder hydraulic synchronous control method and system |
CN115178863A (en) * | 2022-07-12 | 2022-10-14 | 江苏亚威机床股份有限公司 | Proportional servo hydraulic lifting workbench device of laser cutting machine |
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CN103671313A (en) * | 2012-08-30 | 2014-03-26 | 北京索普液压机电有限公司 | Hydraulic pressing machine capable of machining transformer coil |
CN204140527U (en) * | 2014-09-12 | 2015-02-04 | 鞍钢集团工程技术有限公司 | A kind of hydraulic system of walking-beam furnace |
CN206368860U (en) * | 2016-12-17 | 2017-08-01 | 中国重型机械研究院股份公司 | A kind of cold bed raise-lower hydraulic sync control device |
-
2016
- 2016-12-17 CN CN201611171340.6A patent/CN106438520A/en active Pending
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
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CN86108883A (en) * | 1985-12-30 | 1987-08-12 | 霍尔比戈液压有限公司 | The synchronizing controls of multi-hydraulic-cylinder transmission |
CN201304418Y (en) * | 2008-12-11 | 2009-09-09 | 中冶东方工程技术有限公司 | A reversal stepping cold bed hydraulic synchronization control device |
CN101758088A (en) * | 2010-01-18 | 2010-06-30 | 北京京诚之星科技开发有限公司 | Cooling-bed hydraulic stepping and tread control device and control method thereof |
CN103671313A (en) * | 2012-08-30 | 2014-03-26 | 北京索普液压机电有限公司 | Hydraulic pressing machine capable of machining transformer coil |
CN204140527U (en) * | 2014-09-12 | 2015-02-04 | 鞍钢集团工程技术有限公司 | A kind of hydraulic system of walking-beam furnace |
CN206368860U (en) * | 2016-12-17 | 2017-08-01 | 中国重型机械研究院股份公司 | A kind of cold bed raise-lower hydraulic sync control device |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN109915628A (en) * | 2019-03-07 | 2019-06-21 | 深圳市华腾精密机械有限公司 | The integrated inserting valve group in water route and vulcanization mechanomotive force water system |
CN109973471A (en) * | 2019-04-11 | 2019-07-05 | 南通大学 | A kind of more fulcrum synchronisation control means of large size hoistable platform and control system |
CN109973471B (en) * | 2019-04-11 | 2020-06-30 | 南通大学 | Multi-fulcrum synchronous control method and system for large lifting platform |
CN110886732A (en) * | 2019-12-10 | 2020-03-17 | 北京北特圣迪科技发展有限公司 | PLC-based multi-stage multi-cylinder hydraulic synchronous control method and system |
CN110886732B (en) * | 2019-12-10 | 2021-10-22 | 北京北特圣迪科技发展有限公司 | PLC-based multi-stage multi-cylinder hydraulic synchronous control method and system |
CN115178863A (en) * | 2022-07-12 | 2022-10-14 | 江苏亚威机床股份有限公司 | Proportional servo hydraulic lifting workbench device of laser cutting machine |
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Application publication date: 20170222 |
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