CN109869377A - A kind of controllable uninstalling system - Google Patents
A kind of controllable uninstalling system Download PDFInfo
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- CN109869377A CN109869377A CN201711258048.2A CN201711258048A CN109869377A CN 109869377 A CN109869377 A CN 109869377A CN 201711258048 A CN201711258048 A CN 201711258048A CN 109869377 A CN109869377 A CN 109869377A
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- controllable
- unloading
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- pressurized strut
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Abstract
A kind of controllable uninstalling system is related to a kind of controllable uninstalling system for structural test hydraulic loaded pressurized strut.For avoided in load physical simulation experiment testpieces accidental injury or, secondary destruction, reduce the threat problem to personal safety, the present invention provides a kind of controllable uninstalling system: using independent controllable unloading control system, controllable unloading hydraulic system, dual bridge sensor constitutes closed-loop system, load(ing) point uninstall process is controlled, test controllable unloading control system adapter tube test when abnormal condition unloading, control unloading proportional direction valve, using dual bridge sensor force feedback value as feedback signal, the power output of pressurized strut is controlled by controlling the hydraulic oil of pressurized strut high pressure chest, realize controllable unloading.Present invention can ensure that each load(ing) point unloads harmony in the case of testing improper unloading, testpieces accidental injury is avoided, improves structural test safety；Unloading curve, discharge time can set according to actual conditions and change, applied widely, easy to adjust.
Description
Technical field
The present invention relates to a kind of controllable uninstalling systems of hydraulic loaded pressurized strut, are used for structural test more particularly to one kind
The controllable uninstalling system of hydraulic loaded pressurized strut.
Background technique
Structural test refers to by applying simulation load to structural body, and it is (stress, displacement, tired to observe and measure performance parameter
Labor service life, amplitude, vibration frequency etc.), so that the working performance and bearing capacity to structural body make correctly evaluation and estimation, and be
Verifying and development structure design provide reliable foundation.Structural testing system is inherently the coordinated loading control system of multichannel
System, i.e., the physical load for carrying out multiple spot to testpieces are simulated.Structural test generally uses electro-hydraulic loading mode, single to load
Channel is made of pressurized strut, servo valve, force snesor, uninstall protection device etc..
The unloading safety in load channel is a major issue in structural test during test, needs to lose in testpieces
Surely, it destroys and the moment of the single load channel failure rapid steady controllable load applied to each load(ing) point is unloaded
It carries.Harmony is unloaded to ensure to test each load(ing) point in the case of improper unloading, avoids testpieces accidental injury or to examination
It tests part and causes secondary destruction, as far as possible extent of the destruction of the reaction structure under normal load state, while reducing to personal safety
Threat, need to carry out controllable uninstalling system research.Therefore, controllable to coordinate when unloading is structural test to testpieces safety and people
The important leverage of body safety has great research significance.
The controllable uninstalling system that the present invention designs is using independent controllable unloading control system and controllably unloads hydraulic system,
And controllable unloading control system is established into corresponding communication mechanism with coordinated loading control system (MTS or MOOG), it can make to tie
Structure is tested improper unloading moment, and it is controllable unloading control system, control that experiment control system is system converting by coordinated loading control
It makes each load channel controllably to coordinate to unload by unloading curve, maximum protection test part safety and personal safety.
Summary of the invention
The technical problem to be solved in the present invention is to provide a kind of controllably unloading for force servo loading procedure electro-hydraulic in structural test
Loading system, it can be ensured that the load for testing each load(ing) point in the case of improper unloading is unloaded by certain curve, guarantees unloading harmony,
Avoid testpieces accidental injury.
In order to solve the above technical problems, the technical solution of the present invention is as follows: the invention mainly passes through following technologies
What scheme was realized: controllable uninstalling system uses independent controllable unloading control system, controllably unloads hydraulic system, dual bridge sensor
Closed-loop system is constituted, load(ing) point uninstall process is controlled.When test load when, coordinated loading control system, servo valve and
Dual bridge sensor constitutes power closed-loop system and is loaded, and controllable unloading control system is constantly in armed state, and test is non-just
Coordinated loading control system switches to controllable unloading control system while testing load hydraulic system release when reason condition unloads, this
When independent controllable unloading control system adapter tube test, controllable unloading hydraulic system unloading proportional direction valve is controlled, with doube bridge
Sensor force value of feedback controls the power output of pressurized strut by controlling the hydraulic oil of pressurized strut high pressure chest as feedback signal,
Realize controllable unloading.
Wherein controllable unloading control system scheme are as follows: when receiving the unloading trigger signal of coordinated loading control system transmission,
Controllable unloading control system sampling sensor current feedback value is as unloading initial order and generates corresponding unloading curve, unloads
Curve ordinate unit is power, and abscissa unit is the time, and the entire uninstall process deadline sets before on-test, zero
Moment ordinate value is sensor feedback value of the force snesor in test protection moment, and last moment ordinate value is zero, and unloading is bent
Line is traditionally arranged to be the junction curve of zero moment point and last moment point, which can be set.Unloading curve is once
The command signal control uninstall process i.e. as controllable unloading control system is generated, uninstall process force snesor is detected and fed back
Feedback signal of the load force as controllable unloading control system, compared with command signal relatively after error signal be input to unloading
It is unloaded with output voltage (electric current) signal of the control amplifier of proportional direction valve, amplifier according to the proportional control of error signal
Load realizes controllable unloading with proportional direction valve.
Controllable uninstalling system realizes the controllable offloading functions of pressurized strut using independent controllable unloading hydraulic system, tests non-
To unload immediately be zero to pressurized strut input pressure when normal condition unloads, during P mouthfuls of discharge degrees of servo valve are zero and servo valve is in
Position state, servo valve and pressurized strut are drawn, the oil circuit between pressure chamber is disconnected by being loaded back into path switch valve, while pressurized strut is drawn, pressure
Hydraulic oil is connected to the unloading that controllable uninstalling system controls with AB mouthfuls of proportional direction valve (or PT mouthfuls) by depressurized circuit in chamber, is
System oil return is connected to unloading with PT mouthfuls of proportional direction valve (or AB mouthfuls)；
Meanwhile controllable unloading design of Hydraulic System has power outage security protective loop, controllable unloading control system breaks down
When automatically cut off unloading proportional direction valve power supply, unloading proportional direction valve power off back valve core built-in acting force of the spring next time
To power-off protection position, two chamber hydraulic oil of pressurized strut is unloaded by the access connected system oil return of proportional direction valve power-off protection position.
The advantages of this invention is each load(ing) point unloading harmony in the case of can ensure that the improper unloading of test, avoids testing
Part accidental injury improves structural test safety；Unloading curve, the discharge time of controllable uninstalling system can be practical according to test
Situation is set and is changed, applied widely, easy to adjust.
Detailed description of the invention
Fig. 1 is coordinated loading control system and controllable unloading control system relational graph；
Fig. 2 is controllable unloading control system control logic figure；
Fig. 3 controllably unloads hydraulic system A schematic diagram；
Fig. 4 controllably unloads hydraulic system B schematic diagram；
The controllable uninstalling system A schematic diagram of Fig. 5；
The controllable uninstalling system B schematic diagram of Fig. 6.
Wherein, 1- high pressure oil is considered, and 2- pilot solenoid valve, 3- one-way throttle valve A, 4- one-way throttle valve B, 5- relief circuit is opened
Valve A is closed, 6- relief circuit switch valve B, 7- are loaded back into path switch valve A, and 8- is loaded back into path switch valve B, 9- servo valve, 10- direct acting
Formula proportional direction valve, 11- throttle valve, 12- check valve A, 13- check valve B, 14- check valve C, 15- check valve D.
Specific embodiment
The invention is mainly to be realized by following technical solutions: controllable uninstalling system is controllably unloaded using independent
Borne control system controllably unloads hydraulic system, dual bridge sensor composition closed-loop system, controls load(ing) point uninstall process.
When testing load, coordinated loading control system, servo valve and dual bridge sensor constitute power closed-loop system and are loaded, and controllable
Unloading control system is constantly in armed state, and coordinated loading control system, which switches to, when test abnormal condition unloads controllably unloads
Borne control system tests load hydraulic system release simultaneously, and controllable unloading control system adapter tube test independent at this time, control can
Control unloading hydraulic system unloading proportional direction valve, using dual bridge sensor force feedback value as feedback signal, by controlling actuation
The hydraulic oil of cylinder high pressure chest controls the power output of pressurized strut, realizes controllable unloading.
Wherein controllable unloading control system scheme are as follows: when receiving the unloading trigger signal of coordinated loading control system transmission,
Controllable unloading control system sampling sensor current feedback value is as unloading initial order and generates corresponding unloading curve, unloads
Curve ordinate unit is power, and abscissa unit is the time, and the entire uninstall process deadline sets before on-test, zero
Moment ordinate value is sensor feedback value of the force snesor in test protection moment, and last moment ordinate value is zero, and unloading is bent
Line is traditionally arranged to be the junction curve of zero moment point and last moment point, which can be set.Unloading curve is once
The command signal control uninstall process i.e. as controllable unloading control system is generated, uninstall process force snesor is detected and fed back
Feedback signal of the load force as controllable unloading control system, compared with command signal relatively after error signal be input to unloading
It is unloaded with output voltage (electric current) signal of the control amplifier of proportional direction valve, amplifier according to the proportional control of error signal
Load realizes controllable unloading with proportional direction valve.
Controllable uninstalling system realizes the controllable offloading functions of pressurized strut using independent controllable unloading hydraulic system, tests non-
To unload immediately be zero to pressurized strut input pressure when normal condition unloads, during P mouthfuls of discharge degrees of servo valve are zero and servo valve is in
Position state, servo valve and pressurized strut are drawn, the oil circuit between pressure chamber is disconnected by being loaded back into path switch valve, while pressurized strut is drawn, pressure
Hydraulic oil is connected to the unloading that controllable uninstalling system controls with AB mouthfuls of proportional direction valve (or PT mouthfuls) by depressurized circuit in chamber, is
System oil return is connected to unloading with PT mouthfuls of proportional direction valve (or AB mouthfuls)；
Meanwhile controllable unloading design of Hydraulic System has power outage security protective loop, controllable unloading control system breaks down
When automatically cut off unloading proportional direction valve power supply, unloading proportional direction valve power off back valve core built-in acting force of the spring next time
To power-off protection position, two chamber hydraulic oil of pressurized strut is unloaded by the access connected system oil return of proportional direction valve power-off protection position.
Controllable uninstalling system A and B are two embodiments of the invention.
Controllable uninstalling system A:
As shown in figure 5, when test loads, pilot solenoid valve 2 is powered the controllable uninstalling system A principle of structural test, and oil circuit connects
Mouthful P to A connection, pilot pressure oil be connected to relief circuit switch valve A5, relief circuit switch valve B6 and be loaded back into path switch valve A7,
It is loaded back into path switch valve B8, relief circuit switch valve A, B is in an off state under the action of pilot pressure oil, and load circuit is opened
Close valve A, B under the action of pilot pressure oil be in connected state, hydraulic oil by servo valve 9, be loaded back into path switch valve A, B into
Two chamber of pressurized strut forms oil circuit closed loop out, and coordinated loading control system forms power closed-loop control by servo valve 9, dual bridge sensor
System carries out test load, and controllable unloading control system is constantly in armed state.
Once testing improper unloading, coordinated loading control system is immediately sent to controllable unloading control system unloading triggering
Signal, controllable unloading control system are started to work, while being sampled current sensor value of feedback as unloading initial order and being generated
Corresponding unloading curve.Unloading curve controls uninstall process as the command signal of controllable unloading control system once generating,
Uninstall process sensor detects and the feedback signal of the load force fed back as controllable unloading control system, with command signal phase
Error signal after comparing is input to the control amplifier of direct action type proportional direction valve 10, output voltage (electric current) letter of amplifier
Number control proportional direction valve 10 proportional according to error signal.When controllable unloading control system receives unloading trigger signal,
Entire test load hydraulic system release immediately, pilot solenoid valve 2 power off, and pilot pressure oil is connected to release with system oil return T, unloads
It carries circuit switching valve A, B spool and is in connected state under spring force, be loaded back into path switch valve A, B spool in spring force
Under the action of be in an off state, servo valve 9 controls blackout and spool and is in middle position；Two cavity pressure oil of pressurized strut is by unloading
Circuit switching valve A, B and one-way throttle valve A, B are carried, is connected to respectively with the AB of direct action type proportional direction valve 10 mouth.Pressurized strut drawing/pressure
Chamber mesohigh chamber hydraulic oil enters system oil return by the controlled restriction of direct action type proportional direction valve 10；Pressurized strut draws/press chamber
The mesolow chamber hydraulic oil restriction system connectivity system oil return controlled by direct action type proportional direction valve 10；Controllable unloading at this time
Control system and direct action type proportional direction valve 10, dual bridge sensor form power closed-loop system, and controllable unloading control system is according to life
At unloading curve control direct action type proportional direction valve 10 controllably unloaded.
When abnormal condition occurs in controllable uninstalling system, 10 power loss of direct action type proportional direction valve, spool is in spring force
Under the action of be located at power outage security protective position, two cavity pressure oil of pressurized strut passes through the power outage security of direct action type proportional direction valve 10
Guard bit connected system oil return, pressurized strut release.
Controllable uninstalling system B:
As shown in fig. 6, when test loads, pilot solenoid valve 2 is powered the controllable uninstalling system B principle of structural test, and oil circuit connects
Mouthful P to A connection, pilot pressure oil be connected to relief circuit switch valve A5, relief circuit switch valve B6 and be loaded back into path switch valve A7,
It is loaded back into path switch valve B8, relief circuit switch valve A, B is in an off state under the action of pilot pressure oil, and load circuit is opened
Close valve 7,8 under the action of pilot pressure oil be in connected state, hydraulic oil by servo valve 9, be loaded back into path switch valve A, B into
Two chamber of pressurized strut forms oil circuit closed loop out, and coordinated loading control system forms power closed-loop control by servo valve 9, dual bridge sensor
System carries out test load, and controllable unloading control system is constantly in armed state.
Once testing improper unloading, coordinated loading control system is immediately sent to controllable unloading control system unloading triggering
Signal, controllable unloading control system are started to work, while being sampled current sensor value of feedback as unloading initial order and being generated
Corresponding unloading curve.Unloading curve controls uninstall process as the command signal of controllable unloading control system once generating,
Uninstall process sensor detects and the feedback signal of the load force fed back as controllable unloading control system, with command signal phase
Error signal after comparing is input to the control amplifier of direct action type proportional direction valve 10, output voltage (electric current) letter of amplifier
Number control direct action type proportional direction valve 10 proportional according to error signal.Controllable unloading control system receives unloading triggering letter
Number when, entire test load hydraulic system release immediately, pilot solenoid valve 2 powers off, and pilot pressure oil is connected to system oil return T and unloads
Pressure, relief circuit switch valve A, B spool are in connected state under spring force, are loaded back into path switch valve A, B spool and exist
It is in an off state under the action of spring force, servo valve 9 controls blackout and spool is in middle position；Pressurized strut two cavity pressures oil
Enter the rectification being made of check valve A12, check valve B13, check valve C14, check valve D15 by relief circuit switch valve A, B
Circuit, pressurized strut are drawn/are pressed chamber mesohigh chamber hydraulic oil to enter system by the controlled restriction of direct action type proportional direction valve 10 and return
Oil；Pressurized strut draws/presses chamber mesolow chamber hydraulic oil to be directly connected to system oil return via commutating circuit；Controllable Unloading Control at this time
System and direct action type proportional direction valve 10, dual bridge sensor form power closed-loop system, and controllable unloading control system is according to generation
Unloading curve control direct action type proportional direction valve 10 is controllably unloaded.
When abnormal condition occurs in controllable uninstalling system, 10 power loss of direct action type proportional direction valve, spool is in spring force
Under the action of be located at power outage security protective position, pressurized strut high pressure chest hydraulic oil is pacified by the power-off of direct action type proportional direction valve 10
The connected system oil return of full guard position, pressurized strut release.
Claims (4)
1. a kind of controllable uninstalling system, including independent controllable unloading control system, controllably unload hydraulic system, doube bridge sensing
Device, it is characterised in that: controllable unloading control system Control experiment when test abnormal condition unloading controls controllable unloading hydraulic pressure system
Direct action type proportional direction valve (10) in system, using dual bridge sensor force feedback value as feedback signal, control pressurized strut high pressure chest
Hydraulic oil controls the power output of pressurized strut；Controllable unloading hydraulic system includes that high pressure oil considers (1), pilot solenoid valve (2), load
Circuit, relief circuit；Load circuit is formed between pressurized strut and servo valve (9), is loaded back into path switch valve A (7), load circuit
Switch valve B (8) participates in control；Relief circuit is formed between pressurized strut and direct action type proportional direction valve (10), has relief circuit to open
Close valve A (5), relief circuit switch valve B (6) participates in control.
2. a kind of controllable uninstalling system described in accordance with the claim 1, it is characterised in that: controllable unloading design of Hydraulic System has disconnected
Electricity security protection circuit, controllable unloading control system automatically cut off direct action type proportional direction valve (10) power supply when breaking down, directly
Dynamic formula proportional direction valve (10) power-off back valve core returns to power-off protection position under built-in acting force of the spring, and pressurized strut draws, presses chamber
Two chamber hydraulic oil are unloaded by the access connected system oil return of direct action type proportional direction valve (10) power-off protection position.
3. according to a kind of controllable uninstalling system described in claims 1 or 2, it is characterised in that: relief circuit has one-way throttle
Valve A (3) and one-way throttle valve B (4) participate in controlling.
4. according to a kind of controllable uninstalling system described in claims 1 or 2, it is characterised in that: relief circuit has throttle valve
(11), check valve A (12), check valve B (13), check valve C (14), check valve D (15) participate in control.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711258048.2A CN109869377A (en) | 2017-12-01 | 2017-12-01 | A kind of controllable uninstalling system |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201711258048.2A CN109869377A (en) | 2017-12-01 | 2017-12-01 | A kind of controllable uninstalling system |
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| CN109869377A true CN109869377A (en) | 2019-06-11 |
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| CN201711258048.2A Pending CN109869377A (en) | 2017-12-01 | 2017-12-01 | A kind of controllable uninstalling system |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113686567A (en) * | 2021-10-26 | 2021-11-23 | 三一重型装备有限公司 | Static loading test system |
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| CN101831860A (en) * | 2009-03-09 | 2010-09-15 | 宝马格有限公司 | The hydraulic control device that is used for the scraper plate of road finisher |
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Application publication date: 20190611 |
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