CN113107554B - Buffering support device that steps down with negative stiffness energy-absorbing characteristic - Google Patents
Buffering support device that steps down with negative stiffness energy-absorbing characteristic Download PDFInfo
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- CN113107554B CN113107554B CN202110551465.6A CN202110551465A CN113107554B CN 113107554 B CN113107554 B CN 113107554B CN 202110551465 A CN202110551465 A CN 202110551465A CN 113107554 B CN113107554 B CN 113107554B
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- 230000003139 buffering effect Effects 0.000 title claims abstract description 21
- 238000003825 pressing Methods 0.000 claims abstract description 30
- 238000010521 absorption reaction Methods 0.000 claims abstract description 24
- 230000000149 penetrating effect Effects 0.000 claims description 6
- 239000011435 rock Substances 0.000 abstract description 5
- 230000008602 contraction Effects 0.000 abstract description 2
- 230000002093 peripheral effect Effects 0.000 abstract description 2
- 239000003245 coal Substances 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 230000004888 barrier function Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000004880 explosion Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000005065 mining Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000003014 reinforcing effect Effects 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
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Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
- E21D15/00—Props; Chocks, e.g. made of flexible containers filled with backfilling material
- E21D15/14—Telescopic props
- E21D15/44—Hydraulic, pneumatic, or hydraulic-pneumatic props
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
- E21D15/00—Props; Chocks, e.g. made of flexible containers filled with backfilling material
- E21D15/50—Component parts or details of props
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- Engineering & Computer Science (AREA)
- Mining & Mineral Resources (AREA)
- Mechanical Engineering (AREA)
- Structural Engineering (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Geology (AREA)
- Vibration Dampers (AREA)
Abstract
A buffering and abdicating support device with negative rigidity and energy absorption characteristics is characterized in that two energy absorption member placing holes are formed in a support cylinder, an upper baffle and a lower baffle are arranged in the upper energy absorption member placing hole, a negative rigidity honeycomb energy absorption member is arranged between the upper baffle and the lower baffle, an upper pressing plate and a lower pressing plate are arranged in the lower energy absorption member placing hole, and the upper pressing plate and the upper baffle as well as the upper pressing plate and the lower pressing plate are fixedly connected through support columns; four evenly distributed telescopic limiting plates are arranged between the upper pressing plate and the lower pressing plate, adjacent telescopic limiting plates are connected through a high-strength spring, a semicircular groove is formed in the surface of the outer peripheral side of each telescopic limiting plate, a semicircular boss is arranged on the inner hole wall of the lower end energy-absorbing member placing hole, the semicircular boss is matched with the semicircular groove in a clamping mode, and a negative-stiffness honeycomb energy-absorbing member is arranged below the lower pressing plate. When the roadway is impacted suddenly, the impact energy of the roadway top plate can be effectively absorbed through the invention, the surrounding rock abdication is realized through the whole or local contraction of the support, the impact on the support is relieved, and the impact resistance of the hydraulic prop is improved.
Description
Technical Field
The invention belongs to the technical field of coal mine safety support, and particularly relates to a buffering abdicating support device with negative rigidity and energy absorption characteristics.
Background
Rock burst is one of the major dynamic disasters in coal mine production, and support is the barrier which most directly faces the impact risk and prevents the instability and the damage of surrounding rocks. The hydraulic prop is a contractible prop which generates working resistance by utilizing the hydraulic pressure and realizes prop lifting and unloading, when the external load exceeds the set threshold value of the hydraulic prop, the safety valve is immediately opened to discharge liquid and release pressure, and when the load is reduced to be within the threshold value, the safety valve is automatically closed. Therefore, a measure of reinforcing the support is usually taken to resist the occurrence of the impact.
However, in a complex and severe mining process, although a common hydraulic prop has strong adaptability, a relatively serious defect exists, namely, the common hydraulic prop does not have the capabilities of absorbing energy and buffering and yielding. When the impact is small, the common hydraulic prop can be resisted, once the impact is large, the flow discharged due to the pressure relief of the safety valve in unit time is certain, and if the pressure cannot be relieved in time in the face of the impact of sudden large load, the hazards of cylinder explosion, sealing ring crushing, pillar buckling and the like can be caused, so that the support failure of the whole support system is caused, and the damage to the coal mine production safety system is caused.
Disclosure of Invention
Aiming at the problems in the prior art, the invention provides a buffering abdicating support device with negative rigidity and energy absorption characteristics, when a roadway is impacted suddenly, the impact energy of a roadway top plate can be effectively absorbed, a top beam is ensured not to be damaged, surrounding rock abdicating is realized through integral or local contraction of a support, so that the impact acting force applied to the support is relieved, the impact resistance of a hydraulic support is further improved, and the safety coefficient of a mine is improved through multi-stage buffering action.
In order to achieve the purpose, the invention adopts the following technical scheme: a buffering abdicating support device with negative stiffness energy absorption characteristics comprises a support cylinder, an upper baffle, a lower baffle, an upper pressure plate, a lower pressure plate, a first support column, a second support column, a third support column, a fourth support column, a telescopic limiting plate, a high-strength spring, a first negative stiffness honeycomb energy absorption member and a second negative stiffness honeycomb energy absorption member; the supporting cylinder is of a cylindrical structure, an inner hole of the supporting cylinder is of a two-stage stepped hole structure, and an inner hole at the upper end of the supporting cylinder is a cylindrical hole and serves as a first energy absorbing component placing hole; an inner hole at the lower end of the supporting cylinder is an inverted cone-shaped hole and serves as a second energy-absorbing member placing hole; the upper baffle is positioned at the orifice of the first energy absorbing component placing hole, and the first support column is vertically and fixedly connected to the center of the lower surface of the upper baffle; the lower baffle is positioned at the hole bottom of the first energy absorbing component placing hole, the lower baffle is fixedly connected with the hole bottom of the first energy absorbing component placing hole through a high-strength bolt, and a support column penetrating and abdicating hole is formed in the center of the lower baffle; the upper end of the second support column is fixedly connected with the lower end of the first support column in a threaded manner, and the lower end of the second support column penetrates through a support column penetrating abdicating hole in the center of the lower baffle and extends into a second energy-absorbing component mounting hole; the upper pressure plate is positioned in the second energy-absorbing member mounting hole, and the lower end of the second supporting column is fixedly connected with the center of the upper surface of the upper pressure plate; the third supporting column is vertically and fixedly connected with the center of the lower surface of the upper pressure plate; the lower pressing plate is positioned below the upper pressing plate, the fourth supporting column is vertically and fixedly connected to the center of the upper surface of the lower pressing plate, and the fourth supporting column is fixedly connected with the third supporting column in a threaded manner; the four telescopic limiting plates are uniformly distributed in the gap between the upper pressing plate and the lower pressing plate along the circumferential direction, and all adjacent telescopic limiting plates are connected through high-strength springs; semicircular bosses are uniformly distributed on the inner hole wall of the second energy-absorbing member containing hole along the circumferential direction, semicircular grooves are formed in the surface of the outer circumferential side of the telescopic limiting plate, and the semicircular grooves are matched with the semicircular bosses in a clamping manner; the first negative-stiffness honeycomb energy absorbing member is positioned in a first energy absorbing member placing hole between the upper baffle and the lower baffle; and the second negative-stiffness honeycomb energy-absorbing member is positioned in a second energy-absorbing member placing hole below the lower pressing plate.
At least two groups of semicircular bosses on the wall of the inner hole of the second energy-absorbing member are arranged along the axial direction.
The high-strength spring is connected with the telescopic limiting plate through a blind hole formed in the side surface of the inner periphery of the telescopic limiting plate.
The upper baffle and the first supporting column are of an integrated structure.
The second supporting column, the upper pressure plate and the third supporting column are of an integrated structure.
The fourth supporting column and the lower pressing plate are of an integrated structure.
The first negative-stiffness honeycomb energy-absorbing member and the second negative-stiffness honeycomb energy-absorbing member are formed by combining a plurality of single-cell negative-stiffness honeycomb structural members in a set proportional array.
The invention has the beneficial effects that:
the buffering abdicating support device with negative rigidity and energy absorption characteristics can effectively absorb the impact energy of the top plate of the roadway when the roadway is suddenly impacted, ensure that the top beam is not damaged, realize the abdicating of surrounding rocks by wholly or locally shrinking the support so as to relieve the impact acting force applied to the support, further improve the impact resistance of a hydraulic prop, and improve the safety coefficient of a mine through the multi-stage buffering action.
Drawings
FIG. 1 is a schematic structural diagram of a buffering abdicating support device with negative stiffness and energy absorption characteristics according to the invention;
FIG. 2 is a schematic structural view of a cushioning abduction support device with negative stiffness energy absorption characteristics (first/second negative stiffness honeycomb energy absorption members are not shown) of the present invention;
FIG. 3 is an assembly diagram of a second support column, an upper press plate, a third support column, a fourth support column, a lower press plate, a telescopic limit plate and a high-strength spring according to the present invention;
fig. 4 is a spatial position relationship diagram of four retractable limiting plates according to the present invention;
FIG. 5 is a schematic view of an integrated structure of the upper baffle plate and the first support column of the present invention;
FIG. 6 is a schematic view of an integrated structure of the second supporting pillar, the upper platen and the third supporting pillar according to the present invention;
FIG. 7 is a schematic view of an integrated structure of a fourth supporting pillar and a lower pressing plate according to the present invention;
FIG. 8 is a schematic structural view of a first negative stiffness honeycomb energy absorbing member of the present invention;
FIG. 9 is a schematic structural view of a second negative stiffness honeycomb energy absorbing member of the present invention;
in the figure, 1-supporting cylinder, 2-upper baffle, 3-lower baffle, 4-upper press plate, 5-lower press plate, 6-first supporting column, 7-second supporting column, 8-third supporting column, 9-fourth supporting column, 10-telescopic limiting plate, 11-high-strength spring, 12-first negative-stiffness honeycomb energy-absorbing component, 13-second negative-stiffness honeycomb energy-absorbing component, 14-first energy-absorbing component placing hole, 15-second energy-absorbing component placing hole, 16-semicircular boss, 17-semicircular groove, 18-blind hole and 19-high-strength bolt.
Detailed Description
The invention is described in further detail below with reference to the figures and the specific embodiments.
As shown in fig. 1 to 9, a buffering abdicating support device with negative stiffness energy absorption characteristics includes a support cylinder 1, an upper baffle 2, a lower baffle 3, an upper pressure plate 4, a lower pressure plate 5, a first support column 6, a second support column 7, a third support column 8, a fourth support column 9, a telescopic limit plate 10, a high-strength spring 11, a first negative stiffness honeycomb energy absorption member 12 and a second negative stiffness honeycomb energy absorption member 13; the supporting cylinder 1 is of a cylindrical structure, the inner hole of the supporting cylinder 1 is of a two-stage stepped hole structure, and the inner hole at the upper end of the supporting cylinder 1 is a cylindrical hole and serves as a first energy absorbing component placing hole 14; an inner hole at the lower end of the support cylinder 1 is an inverted cone-shaped hole and serves as a second energy-absorbing member placing hole 15; the upper baffle 2 is positioned at the orifice of the first energy absorbing component placing hole 14, and the first support column 6 is vertically and fixedly connected to the center of the lower surface of the upper baffle 2; the lower baffle 3 is positioned at the hole bottom of the first energy absorbing component placing hole 14, the lower baffle 3 is fixedly connected with the hole bottom of the first energy absorbing component placing hole 14 through a high-strength bolt 19, and a support column penetrating abdicating hole is formed in the center of the lower baffle 3; the upper end of the second support column 7 is fixedly connected with the lower end of the first support column 6 in a threaded manner, and the lower end of the second support column 7 penetrates through a support column penetrating abdicating hole in the center of the lower baffle 3 and extends into a second energy-absorbing member placing hole 15; the upper pressure plate 4 is positioned in the second energy-absorbing member placing hole 15, and the lower end of the second supporting column 7 is fixedly connected with the center of the upper surface of the upper pressure plate 4; the third supporting column 8 is vertically and fixedly connected to the center of the lower surface of the upper pressure plate 4; the lower pressing plate 5 is positioned below the upper pressing plate 4, the fourth supporting column 9 is vertically and fixedly connected to the center of the upper surface of the lower pressing plate 5, and the fourth supporting column 9 and the third supporting column 8 are fixedly connected together in a threaded manner; the four telescopic limiting plates 10 are uniformly distributed in the gap between the upper pressing plate 4 and the lower pressing plate 5 along the circumferential direction, and all the adjacent telescopic limiting plates 10 are connected through high-strength springs 11; semicircular bosses 16 are uniformly distributed on the inner hole wall of the second energy-absorbing member accommodating hole 15 along the circumferential direction, a semicircular groove 17 is formed in the surface of the outer circumferential side of the telescopic limiting plate 10, and the semicircular groove 17 is matched with the semicircular bosses 16 in a clamping manner; the first negative-stiffness honeycomb energy-absorbing member 12 is positioned in a first energy-absorbing member placing hole 14 between the upper baffle 2 and the lower baffle 3; the second negative-stiffness honeycomb energy-absorbing member 13 is positioned in a second energy-absorbing member placing hole 15 below the lower pressing plate 5.
At least two groups of semicircular bosses 16 on the inner hole wall of the second energy-absorbing member containing hole 15 are arranged along the axial direction.
The high-strength spring 11 is connected with the telescopic limit plate 10 through a blind hole 18 formed in the inner peripheral side surface of the telescopic limit plate 10.
The upper baffle plate 2 and the first supporting column 6 adopt an integrated structure.
The second supporting column 7, the upper pressure plate 4 and the third supporting column 8 adopt an integrated structure.
The fourth supporting column 9 and the lower pressing plate 5 adopt an integrated structure.
The first negative stiffness honeycomb energy absorbing member 12 and the second negative stiffness honeycomb energy absorbing member 13 are formed by combining a plurality of single-cell negative stiffness honeycomb structural members in a set proportional array.
The one-time use process of the present invention is described below with reference to the accompanying drawings:
the buffering abdicating support device with negative rigidity and energy absorption characteristics is installed at the top end of a hydraulic prop, when the hydraulic prop is impacted, a load force firstly acts on an upper baffle 2 and is transmitted to a telescopic limit plate 10 through a first support column 6, a second support column 7 and an upper pressure plate 4 in sequence, if the load force is small, a semicircular groove 17 on the telescopic limit plate 10 cannot be forced to be separated from the limitation of a semicircular boss 16 under the action of an initial support force provided by a high-strength spring 11, and at the moment, rigid support can be enough to resist the load.
If the load force is large, even if the load force is acted by the initial supporting force provided by the high-strength spring 11, the semicircular groove 17 on the telescopic limiting plate 10 is forced to be separated from the limitation of the semicircular lug boss 16, at the moment, the upper baffle 2, the first supporting column 6, the second supporting column 7 and the upper pressure plate 4 synchronously move downwards, the high-strength spring 11 is forced to contract, meanwhile, the telescopic limiting plate 10 and the inclined inner hole wall of the second energy-absorbing member containing hole 15 rub, further, a part of vertically downward load is decomposed into horizontal load, meanwhile, the first negative-rigidity honeycomb energy-absorbing member 12 and the second negative-rigidity honeycomb energy-absorbing member 13 are compressed until the semicircular groove 17 on the telescopic limiting plate 10 and the semicircular lug boss 16 below continue to buffer, finally, the rapid energy-absorbing buffering yielding is realized, the safety valve of the hydraulic prop is ensured to have enough opening time, the impact resistance of the hydraulic prop is improved, and the safety of the whole supporting system is protected.
The embodiments are not intended to limit the scope of the present invention, and all equivalent implementations or modifications without departing from the scope of the present invention are intended to be included in the scope of the present invention.
Claims (7)
1. The utility model provides a buffering support device that lets with negative stiffness energy-absorbing characteristic which characterized in that: the device comprises a support cylinder, an upper baffle, a lower baffle, an upper pressure plate, a lower pressure plate, a first support column, a second support column, a third support column, a fourth support column, a telescopic limiting plate, a high-strength spring, a first negative-stiffness honeycomb energy-absorbing component and a second negative-stiffness honeycomb energy-absorbing component; the supporting cylinder is of a cylindrical structure, an inner hole of the supporting cylinder is of a two-stage stepped hole structure, and an inner hole at the upper end of the supporting cylinder is a cylindrical hole and serves as a first energy absorbing component placing hole; an inner hole at the lower end of the support cylinder is an inverted conical hole and serves as a second energy-absorbing member placement hole; the upper baffle is positioned at the orifice of the first energy absorbing component placing hole, and the first support column is vertically and fixedly connected to the center of the lower surface of the upper baffle; the lower baffle is positioned at the hole bottom of the first energy absorbing component placing hole, the lower baffle is fixedly connected with the hole bottom of the first energy absorbing component placing hole through a high-strength bolt, and a support column penetrating and abdicating hole is formed in the center of the lower baffle; the upper end of the second support column is fixedly connected with the lower end of the first support column in a threaded manner, and the lower end of the second support column penetrates through a support column penetrating abdicating hole in the center of the lower baffle and extends into a second energy-absorbing component mounting hole; the upper pressure plate is positioned in the second energy-absorbing member mounting hole, and the lower end of the second supporting column is fixedly connected with the center of the upper surface of the upper pressure plate; the third supporting column is vertically and fixedly connected to the center of the lower surface of the upper pressure plate; the lower pressing plate is positioned below the upper pressing plate, the fourth supporting column is vertically and fixedly connected to the center of the upper surface of the lower pressing plate, and the fourth supporting column is fixedly connected with the third supporting column in a threaded manner; the four telescopic limiting plates are uniformly distributed in the gap between the upper pressing plate and the lower pressing plate along the circumferential direction, and all adjacent telescopic limiting plates are connected through high-strength springs; semicircular bosses are uniformly distributed on the inner hole wall of the second energy-absorbing member containing hole along the circumferential direction, semicircular grooves are formed in the surface of the outer circumferential side of the telescopic limiting plate, and the semicircular grooves are matched with the semicircular bosses in a clamping manner; the first negative-stiffness honeycomb energy absorbing member is positioned in a first energy absorbing member placing hole between the upper baffle and the lower baffle; and the second negative-stiffness honeycomb energy-absorbing member is positioned in a second energy-absorbing member placing hole below the lower pressing plate.
2. The buffering and abdicating support device with negative rigidity and energy absorption characteristics as claimed in claim 1, wherein: and at least two groups of semicircular bosses on the wall of the second energy-absorbing member containing hole are arranged along the axial direction.
3. The buffering and abdicating support device with negative rigidity and energy absorption characteristics as claimed in claim 1, wherein: the high-strength spring is connected with the telescopic limiting plate through a blind hole formed in the side surface of the inner periphery of the telescopic limiting plate.
4. The buffering and abdicating support device with negative rigidity and energy absorption characteristics as claimed in claim 1, wherein: the upper baffle and the first supporting column are of an integrated structure.
5. The buffering and abdicating support device with negative rigidity and energy absorption characteristics as claimed in claim 1, wherein: the second supporting column, the upper pressure plate and the third supporting column are of an integrated structure.
6. The buffering and abdicating support device with negative rigidity and energy absorption characteristics as claimed in claim 1, wherein: the fourth supporting column and the lower pressing plate are of an integrated structure.
7. The buffering and abdicating support device with negative rigidity and energy absorption characteristics as claimed in claim 1, wherein: the first negative-stiffness honeycomb energy-absorbing component and the second negative-stiffness honeycomb energy-absorbing component are formed by combining a plurality of single-cell negative-stiffness honeycomb structural components in a set proportional array.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110551465.6A CN113107554B (en) | 2021-05-20 | 2021-05-20 | Buffering support device that steps down with negative stiffness energy-absorbing characteristic |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110551465.6A CN113107554B (en) | 2021-05-20 | 2021-05-20 | Buffering support device that steps down with negative stiffness energy-absorbing characteristic |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113107554A CN113107554A (en) | 2021-07-13 |
| CN113107554B true CN113107554B (en) | 2023-03-14 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202110551465.6A Active CN113107554B (en) | 2021-05-20 | 2021-05-20 | Buffering support device that steps down with negative stiffness energy-absorbing characteristic |
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Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102418538B (en) * | 2011-11-16 | 2013-12-04 | 辽宁工程技术大学 | High-speed energy absorption anti-impact retreat hydraulic support for coal mine |
| CN105041350B (en) * | 2015-06-02 | 2017-05-17 | 辽宁工程技术大学 | Hydraulic prop having anchoring force energy-absorbing buffering function |
| CN104989436B (en) * | 2015-06-02 | 2017-03-29 | 辽宁工程技术大学 | A kind of shock proof drift section hydraulic support of energy-absorption type |
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