CN208669329U - A buffer system and hydraulic support for hydraulic support to resist impact ground pressure - Google Patents
A buffer system and hydraulic support for hydraulic support to resist impact ground pressure Download PDFInfo
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- CN208669329U CN208669329U CN201821112186.XU CN201821112186U CN208669329U CN 208669329 U CN208669329 U CN 208669329U CN 201821112186 U CN201821112186 U CN 201821112186U CN 208669329 U CN208669329 U CN 208669329U
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Abstract
本实用新型涉及一种用于液压支架抗冲击地压的缓冲系统及液压支架，包括立柱，立柱包括依次连接的活柱、中部油缸、底部油缸和抗冲击缓冲器，抗冲击缓冲器上设置有相连接的压力传感器和控制器，控制器还与抗冲击缓冲器内的磁流变线圈电连接；通过压力传感器采集压力信息，由控制器实时调节及通断磁流变线圈的电流，使抗冲击缓冲器辅助缓冲立柱受到的冲击地压。本实用新型抗冲击地压的缓冲系统可以方便地集成到现有液压支架结构上，方便安装与现有液压支架配套使用。改变了传统依靠大流量安全阀泄压的单一方式，采用该缓冲系统后能够有效保护立柱的缓冲泄压过程，同时提升液压支架抗冲击地压时的可靠性，保障液压支架安全有效地工作。
The utility model relates to a buffer system and a hydraulic support for a hydraulic support to resist impact ground pressure, comprising a vertical column, wherein the vertical column comprises a movable column, a middle oil cylinder, a bottom oil cylinder and an anti-shock buffer which are connected in sequence. The connected pressure sensor and controller, the controller is also electrically connected with the magnetorheological coil in the anti-shock buffer; the pressure information is collected by the pressure sensor, and the current of the magnetorheological coil is adjusted and turned on and off by the controller in real time, so that the anti-shock The shock absorber assists in buffering the shock ground pressure received by the column. The impact-resistant ground pressure buffer system of the utility model can be easily integrated into the existing hydraulic support structure, and is convenient to be installed and used together with the existing hydraulic support. It has changed the traditional single method of relying on high-flow safety valve to relieve pressure. After adopting this buffer system, it can effectively protect the buffer pressure relief process of the column, and at the same time improve the reliability of the hydraulic support against impact ground pressure, and ensure the safe and effective operation of the hydraulic support.
Description
Technical field
The utility model relates to a kind of buffer system pressed for hydraulic support shock resistance and hydraulic supports, belong to mine
Support technology field.
Background technique
With the increase of exploitation of coal resources depth and mining rate, the dynamic disasters such as Rock Burst increasingly sharpen,
Seriously threaten the safety of coal mining.Bump refers to roadway or working face surrounding rock body, due to elastic deformation energy
Instantaneous relase and generate the dynamic phenomenon that acutely destroys suddenly, be often accompanied by coal and rock dish out, loud noise and phenomena such as blast.
Statistical analysis shows the report that various types of mines have bump to occur, and all kinds of coal seams all overshoot
Hit phenomenon, geological structure from simple to complexity, coal seam from thin to special thick, inclination angle from level to high-dipping, conglomerate, sandstone, limestone,
Oil shale top plate is pressed overbump all occurs.Not only the extent of injury is big for coal mine rock burst, influence it is wide, and be induce its
The root of its coal mine major accident.Bump may induce the particularly serious disaster such as outburst coal mass, gas explosion.
The problem of seriously affecting Safety of Coal Mine Production for reply bump, many schemes that technical staff proposes substantially may be used
It is active and two kinds of passive type to be divided into:
Active scheme, which is used, carries out pretreated measure to top plate, brings it about controllable spontaneous caving, prevents coal
The mine impact that top plate is caving generation suddenly during normal production damages equipment and operating personnel.It is broken for face roof
There is the region for being caving danger often to use active scheme.
Due to the uncertainty that bump occurs, proactive cannot fully control the generation of bump.Therefore
It is good for roof condition, it is not easy to find the working face of bump tendency, often uses passive type scheme.Passive type method master
If reducing bump damage using the pressure release buffering of the support apparatus such as hydraulic support.For hydraulic in passive type method
For bracket support, current main solution:
(1) mine hydraulic bracket generallys use and installs high-flow safety valve additional inside column and solve shock problem at present,
By high-flow safety valve, the mode of off-load prevents bump from causing brokenly to bracket and pillar construction after being more than to set pressure
It is bad；(2) patent (CN105134260B) proposition solves shock problem using the thinking for cylinder increase-volume of rising, and increase-volume buffers strength anti-impact
It hits double-telescopic upright post and is divided into air chamber increase-volume strength shock resistance double-telescopic upright post and the increase-volume strength shock resistance double-telescopic upright post that rises,
Its hollow gas chamber increase-volume double-telescopic upright post is setting empty room gas-liquid strut device, middle cylinder after being hit using column inside movable post
Air chamber inside pressure increase compression movable post buffers to realize；The increase-volume double-telescopic upright post that rises is that the cylinder that rises is arranged inside movable post
Structure realizes buffering by the flexible deformation for the cylinder that rises.(3) high-speed energy absorption anti-impact retreat hydraulic support for coal mine (patent No.
CN201110363855.7 energy-absorbing impact-proof structure (more sky foamed aluminiums, polyurethane mainly) are additionally arranged at the bottom in hydraulic support column
Class material, rubber material etc.) it is buffered to absorb impact energy realization.
There are still following problems not yet to solve for above method:
1, bracket can not press earthquake intensity and intensity according to bump to carry out active adjusting and reply.
2, buffer structure is installed additional in column ontology and influence is caused on original bracket and pillar construction, increase manufacture work
Skill complexity and production cost；
3, huge surge is often generated when bump occurs, for installing high-flow safety valve additional inside column
Mode for, high-flow safety valve needs to discharge a large amount of oil liquid to uninstall this part surge.Since bump is made
Very short with the time, bump process duration only continued several milliseconds when shock loading maximum and arrives at several seconds to tens seconds
A few tens of milliseconds, high-flow safety valve can not timely respond to during often leading to bump from occurring end, therefore make
The appearance of the problems such as at column bending, fracture, detonation, has seriously affected production safety.
Therefore the utility model proposes a kind of buffer system pressed for hydraulic support shock resistance it is (hereinafter referred to as hydraulic
Bracket shock resistance system) just focus on solving when bump occurs surge pressure excessively high timely buffering off-load and according to pressing master
Dynamic the problem of adjusting buffer damping.This method can effectively solve the problems, such as such shock resistance, improve the speed and reality of column response
Effect property, while facilitating application and replacement.
Utility model content
In view of the deficiencies of the prior art, the utility model provides a kind of buffer system pressed for hydraulic support shock resistance
System.
The technical solution of the utility model is as follows:
A kind of buffer system pressed for hydraulic support shock resistance, including column, column include sequentially connected movable post,
Middle part oil cylinder, bottom oil cylinder and shock resistance buffer are provided with the pressure sensor being connected and control on shock resistance buffer
Device, controller are also electrically connected with the magnetic current type transformer coil in shock resistance buffer；Pressure information is acquired by pressure sensor, by controlling
Device processed adjusts in real time and the electric current of on-off magnetic current type transformer coil, the bump for being subject to shock resistance buffer auxiliary buffering upright.
Preferably, the shock resistance buffer includes sequentially connected portable pillar, top oil cylinder, flameproof enclosure and lower part oil
Cylinder；Connector is provided in flameproof enclosure, connector is wound with described for connecting top oil cylinder and lower part oil cylinder on connector
Magnetic current type transformer coil and connector axial direction on be through with multiple damping holes.
Preferably, the movable top end is equipped with concave support base, and concave support base and the cylinder barrel of bottom oil cylinder rigidly connect
It connects.
Preferably, the top oil cylinder includes epicoele cylinder body, epicoele piston and upper cavity end cap, the bottom of epicoele cylinder body and company
The connection of junctor upper end, epicoele piston are located in epicoele cylinder body and by upper cavity end cap encapsulation, portable pillar run through upper cavity end cap with it is upper
The connection of chamber piston, pressure sensor are installed on the bottom of epicoele cylinder body, are also provided with liquid injection port on epicoele cylinder body.
Preferably, the lower part oil cylinder includes cavity of resorption cylinder body, cavity of resorption piston, spring and pedestal, the top of cavity of resorption cylinder body with
The connection of connector lower end, cavity of resorption piston, spring are sequentially loaded into cavity of resorption cylinder body and are encapsulated by pedestal.
Preferably, the bottom of the epicoele cylinder body and connector upper end junction, cavity of resorption cylinder body top and connector under
End junction is separately installed with sealing ring.
Preferably, the shape of the pedestal is hemispherical.This design is advantageous in that, pedestal is designed to and traditional column
Similar spherical structure, it is convenient to be connect with the needling of hydraulic support foundation.
Preferably, helicla flute is offered on the connector, the magnetic current type transformer coil is wrapped in connector along helicla flute
On.
A kind of hydraulic support, including top beam, pedestal and above-mentioned buffer system, the column be located at top beam and pedestal it
Between, movable post is connect with top beam, and the pedestal of shock resistance buffer and the pedestal of hydraulic support connect.
The utility model has the beneficial effects that:
1. in the utility model buffer system magnetic current type transformer coil be arranged in outside damp channel by flameproof enclosure and it is extraneous every
From magnetic current type transformer coil can be operated by opening flameproof enclosure, be convenient for changing and repaired.Controller uses dynamic regulation strategy, buffering
It adjusts hydraulic support shock resistance system damping power in real time in the process, actively increases the pressure amount that allows when buffer cavity pressure is excessively high, mention
High cushion performance.
2. improved hydraulic support uses series buffer thinking, can basis for the hydraulic support used under different operating conditions
Its working environment sets the surge pressure and maximum output current parameter of system controller, and control coil electric current is thus to hydraulic branch
Frame shock resistance system provides corresponding damping force, applies buffer system more flexible, and buffering course is more steady, reliable.
Surge pressure parameter is added in the controller simultaneously, when surge is greater than hydraulic support shock resistance system peak pressure
When power, the power-off of controller control coil makes buffer quick pressure releasing protective cradle column, and response speed is better than big flow safety again
Valve.
3. the buffer system pressed to the utility model shock resistance is integrated on existing hydraulic rack structure in which can be convenient, side
Just installation is matched with existing hydraulic support.The single mode that tradition relies on high-flow safety valve pressure release is changed, using this
It is reliable when capableing of the buffering pressure leak process of effective protection column after buffer system, while pressing with promoting hydraulic support shock resistance
Property, ensure that hydraulic support safely and effectively works.
Detailed description of the invention
Fig. 1 is the overall structure diagram of the utility model buffer system；
Fig. 2 is the structural schematic diagram of shock resistance buffer in the utility model；
Fig. 3 is the sectional view of shock resistance buffer in the utility model；
Fig. 4 is the utility model buffer system top cylinder structure schematic diagram；
Fig. 5 is damp channel structure chart in the utility model；
Fig. 6 is the utility model buffer system lower part cylinder structure schematic diagram；
Wherein: 1, movable post；2, middle part oil cylinder；3, bottom oil cylinder；4, shock resistance buffer；401, portable pillar；402, top
Oil cylinder；403, flameproof enclosure；404, lower part oil cylinder；405, sealing ring；406, spring；407, upper cavity end cap；408, liquid injection port；
409, sealing ring；4010, magnetic current type transformer coil；4011, damping hole；4012, cavity of resorption cylinder body；4013, cavity of resorption piston；4014, pedestal；
4015, connector；4016, epicoele cylinder body；4017, cavity of resorption end cap；5, pressure sensor；6, controller；7, damp channel.
Specific embodiment
The utility model is described further by way of example and in conjunction with the accompanying drawings, but not limited to this.
Embodiment 1:
As shown in Figures 1 to 6, the present embodiment provides a kind of buffer systems pressed for hydraulic support shock resistance, this is slow
Flushing system mainly includes modified column, and column includes from top to bottom sequentially connected movable post 1, middle part oil cylinder 2, bottom oil cylinder 3
With shock resistance buffer 4, be provided with the pressure sensor 5 and controller 6 being connected on shock resistance buffer 4, controller 6 also with
Magnetic current type transformer coil electrical connection in shock resistance buffer 4；Pressure information is acquired by pressure sensor 5, is adjusted in real time by controller 6
The electric current of section and on-off magnetic current type transformer coil, the bump for making shock resistance buffer 4 that buffering upright be assisted to be subject to.
Technical solution provided in this embodiment, in the single side pressed by high-flow safety valve shock absorbing of column tradition
Under formula, by adding intelligentized control method shock resistance buffer in column bottom end, combines, can ensure vertical with high-flow safety valve
Column fast and effeciently pressure release when by bump avoids column buffering pressure release from causing damage situations not in time.
Wherein, the primary structure of shock resistance buffer includes from top to bottom sequentially connected portable pillar 401, top oil cylinder
402, flameproof enclosure 403 and lower part oil cylinder 404；Connector 4015 is provided in flameproof enclosure 403, connector 4015 is for connecting
Top oil cylinder 402 and lower part oil cylinder 404 are wound on connector 4015 in the magnetic current type transformer coil 4010 and connector axial direction
There are four damping hole 4011, four damping holes 4011 constitute connection top oil cylinder (oil pocket) and lower part oil cylinder (oil for perforation
Chamber) damp channel 7.
401 top of portable pillar is designed specifically to concave support base, and concave support base and the cylinder barrel of bottom oil cylinder 3 rigidly connect
It connects.Hydraulic support column is that the spherical of column lower part and the spherical at bracket needling fit when assembling with pedestal, from
And bracket base is made to achieve the purpose that carry column.When setting prop or drop column, column and bracket base occur relatively bracket
Dry friction occurs for movement, bracket needling and column bottom spherical.So being installed additional designed by utility model to reduce as far as possible
To the influence of bracket overall structure and pillar construction after buffer, buffer movable post column cap is designed to and bracket needling structure one
It causes, that is, is that spherical (such as Fig. 2, shown in 401 structures) is also assembled with column and bracket base when column and buffer assemble
Unanimously, i.e., column bottom spherical is combined with buffer movable post column cap spherical, and dry friction occurs for when relative motion.Guarantee branch
Support force and impact force prolong the transmitting of shock resistance system axis, prevent that situations such as askew, pressure is inclined is pressed to influence hydraulic support normal work.
Top oil cylinder 402 includes epicoele cylinder body 4016, epicoele piston and upper cavity end cap 407, the bottom of epicoele cylinder body 4016
It is connect with 4015 upper end of connector, epicoele piston is located in epicoele cylinder body 4016 and is encapsulated by upper cavity end cap 407, portable pillar
401 connect through upper cavity end cap 407 with epicoele piston, and pressure sensor 5 is installed in the pilot hole of the bottom of epicoele cylinder body 4016
And be connected with controller 6 and external power supply, liquid injection port 408 is also provided on epicoele cylinder body 4016.
Lower part oil cylinder 404 includes cavity of resorption cylinder body 4012, cavity of resorption piston 4013, spring 406 and pedestal 4014, cavity of resorption cylinder body
4012 top is connect with 4015 lower end of connector, and cavity of resorption piston 4013, spring 406 are sequentially loaded into cavity of resorption cylinder body and pass through bottom
Seat 4014 encapsulates.The shape of pedestal 4014 is hemispherical, and pedestal is designed to spherical structure similar with traditional column, it is convenient and
The needling of hydraulic support foundation connects.
In addition, the bottom of epicoele cylinder body 4016 and 4015 upper end junction of connector, the top of cavity of resorption cylinder body 4012 and company
4015 lower end junction of junctor is separately installed with sealing ring 409,405.
Helicla flute is offered on connector 4015, magnetic current type transformer coil 4010 is wrapped on connector 4015 along helicla flute.Control
Device 6 processed is electrically connected with magnetic current type transformer coil 4010, realizes shock resistance by the electric current of real-time regulation and control magnetic current type transformer coil 4010
The operation of buffer.
The working principle of the present embodiment buffer system:
1, system parameter settings (including the setting of controller current parameters and pressure sensor surge pressure parameter setting)
(1) controller current parameters are set
Controller is fixed on buffer cylinder barrel outer wall, to magnetic after the pressure signal that pressure sensor acquires is compared
Rheology coil inputs electric current of corresponding size.
The determination basis of this size of current is:
On the one hand, the damping force that buffer provides under the operation of this electric current must be more than or equal to hydraulic support column and work normally
When working resistance, with this ensure hydraulic support work normally when shock resistance system do not act.
On the other hand, when pressure sensor detects that pressure increases, signal is passed to controller by pressure sensor, control
Device processed adjusts current value in real time makes buffer rigidity be less than column rigidity, prevents column to be crushed bad.
(2) controller surge pressure parameter setting
When setting pressure sensor surge pressure, it is adjusted according to hydraulic support column maximum operation resistance, it is ensured that
When bump occurs, hydraulic support shock resistance system is corresponding rapidly, acts prior to hydraulic support column high-flow safety valve.
2, hydraulic support shock resistance system control strategy (program setting in controller)
Controller is passed using adjusting plus on-off control strategy in real time, pressure in hydraulic support shock resistance system work process
The buffer upper cavity pressure measured is transferred to controller by sensor, controller by it with setting without bump when buffer on
Cavity pressure maximum value is compared.
If buffer upper cavity pressure maximum value is P1 when no bump, the buffer upper cavity pressure value measured in real time is
P2, the surge pressure that controller is set is Pm.
As P1=P2 < Pm, controller controls power supply and exports normal current to magnetic current type transformer coil；
As P1 < P2 < Pm, the electric current that controller control power supply is exported to magnetic current type transformer coil accordingly reduces；
As P1 < Pm < P2, controller controls magnetorheological coil blackout, so that magnetorheological fluid is restored to Newtonian fluid state fast
Speed reduces upper cavity pressure by damp channel, to make buffer acquisition is larger pressure amount is allowed to reduce impact peak value pressure, makes to buffer
Process is more steady.
3, hydraulic support shock resistance system work process (action process when pressing to entire column shock resistance)
(1) when column is not affected by shock loading, shock resistance buffer activity column is under the action of cavity of resorption spring in top
The state of liter.Power on and power to coil electrifying system, upper cavity pressure is less than the surge pressure of setting, controller control electricity at this time
Source provides corresponding damping force to coil power supply, buffer for buffer system, makes buffer that there is certain rigidity to guarantee hydraulic support
It works normally unaffected.
(2) when column is by shock loading, according to load condition, reduced by controller or disconnect power supply and give coil electricity
Stream, impact energy are transmitted on shock resistance buffer via hydraulic support column, and epicoele magnetorheological fluid is made by portable pillar pushing
Chamber becomes high pressure chest, and the effect of magnetorheological fluid compression power flows into cavity of resorption through damp channel by epicoele, buffer function realized, so that hydraulic
The high-flow safety valve of bracket upright post installation has enough time to open pressure release, discharges remaining impact energy.Entire buffered
Since buffer rigidity is less than hydraulic support column rigidity in journey, so buffer can pacify prior to column big flow when impact occurs
Full valve movement.Pressure amount is allowed also to be not enough to dissipate impact energy so that hydraulic support column cavity pressure increases when buffer
When, the high-flow safety valve of column opens pressure release.
(3) top plate has certain amount of moving down after bump process, and will not restore.
Embodiment 2:
A kind of hydraulic support, including top beam, pedestal and buffer system described in embodiment 1, by the modified of embodiment 1
Column is installed between top beam and pedestal, and movable post 1 is connect with top beam, the pedestal 4014 of shock resistance buffer and the bottom of hydraulic support
Seat connection.
Embodiment 3:
The working method for the buffer system pressed as described in Example 1 for hydraulic support shock resistance, specific works mistake
Journey the following steps are included:
(1) column in 1 buffer system of embodiment traditional column is substituted to be mounted on hydraulic support, wherein movable post 1 with
Top beam connection, the pedestal 4014 of shock resistance buffer are connect with the pedestal of hydraulic support, and pressure sensor 5 and controller 6 also divide
It Lian Jie not external power supply；
(2) when the top plate of hydraulic support bump, column occurs by shock loading, set cap is moved down, pressure
Sensor 5 collects pressure signal and is transferred to controller 6, and controller 6 adjusts in real time and the electric current of on-off magnetic current type transformer coil, makes to resist
Shock eliminator generates damping force, prior to high-flow safety valve operation, realizes buffer function；
(3) when shock resistance buffer depletion impact energy, so that the high-flow safety valve of hydraulic support column has enough
Time opens pressure release, subsequent to discharge remaining impact energy (when what is fallen more than shock resistance buffer depletion by shock resistance buffer
After maximum impact energy, remaining impact energy is then fallen by high-flow safety valve pressure release, and shock resistance buffer is big flow safety
Time enough has been striven in the response of valve).
After bump process, top beam has certain amount of moving down and will not reply, therefore bump process knot
Shu Houxu reduces hydraulic support shock resistance system altitude, disconnects shock resistance buffer power supply, magnetorheological fluid is restored to newton at this time
Fluid state, in shock resistance buffer lower part under the action of oil cylinder inner spring, the magnetorheological fluid of cavity of resorption, which will be pushed through epicoele, to be delayed
Compressed movable post ejects completely during punching, completes the reset of shock resistance buffer.
Claims (9)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201821112186.XU CN208669329U (en) | 2018-07-13 | 2018-07-13 | A buffer system and hydraulic support for hydraulic support to resist impact ground pressure |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201821112186.XU CN208669329U (en) | 2018-07-13 | 2018-07-13 | A buffer system and hydraulic support for hydraulic support to resist impact ground pressure |
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| CN208669329U true CN208669329U (en) | 2019-03-29 |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111677535A (en) * | 2019-09-11 | 2020-09-18 | 重庆交通大学 | Adaptive yielding support device |
| DE112021002750T5 (en) | 2021-02-23 | 2023-03-02 | Shandong University Of Science And Technology | A composite shock absorbing device and its application |
-
2018
- 2018-07-13 CN CN201821112186.XU patent/CN208669329U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111677535A (en) * | 2019-09-11 | 2020-09-18 | 重庆交通大学 | Adaptive yielding support device |
| DE112021002750T5 (en) | 2021-02-23 | 2023-03-02 | Shandong University Of Science And Technology | A composite shock absorbing device and its application |
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