CN113482676A - Solid-liquid coupling energy-absorbing scour protection stand - Google Patents
Solid-liquid coupling energy-absorbing scour protection stand Download PDFInfo
- Publication number
- CN113482676A CN113482676A CN202110877754.5A CN202110877754A CN113482676A CN 113482676 A CN113482676 A CN 113482676A CN 202110877754 A CN202110877754 A CN 202110877754A CN 113482676 A CN113482676 A CN 113482676A
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- China
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- cylinder body
- outer cylinder
- piston
- inner cavity
- upright post
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- E—FIXED CONSTRUCTIONS
- E21—EARTH 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
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH 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
- E21D15/51—Component parts or details of props specially adapted to hydraulic, pneumatic, or hydraulic-pneumatic props, e.g. arrangements of relief valves
Abstract
The invention discloses a solid-liquid coupling energy-absorbing impact-proof upright post, wherein one end of an outer cylinder body is opened, the other end of the outer cylinder body is connected with a cylinder bottom, a sealing structure is arranged between the outer cylinder body and the cylinder bottom, a movable cylinder body extends into an inner cavity of the outer cylinder body from the open end of the outer cylinder body, a liquid inlet communicated with the inner cavity of the outer cylinder body is also arranged on the side wall of the outer cylinder body, a hydraulic lock is arranged outside the outer cylinder body, a bottom piston is also arranged in the inner cavity of the outer cylinder body, an energy absorber is also arranged on one side, facing the cylinder bottom, of the bottom piston, the energy absorber is contacted with the bottom surface of the inner cavity of the cylinder bottom, a moving area for the bottom piston to slide towards the direction of the cylinder bottom along the axial direction of the inner side wall of the outer cylinder body and/or the cylinder bottom is also arranged on the inner side wall of the outer cylinder body and/or the cylinder bottom, and the bottom piston is in sealing fit with the moving area; the liquid inlet is arranged close to the bottom piston and is positioned between the bottom piston and the movable column body. The invention fixes the energy absorber and the bottom piston together, the energy absorber is positioned in the cylinder bottom, the occupied space is small, the stroke of the upright post is large, the quick abdication of the instantaneous high-pressure load acting on the live post is realized, and the maximum relay which can be borne by the anti-impact upright post is improved.
Description
Technical Field
The invention belongs to the technical field of hydraulic supports, and particularly relates to a solid-liquid coupling energy-absorbing impact-resistant upright post.
Background
The occurrence of the ground pressure impact is generally free of obvious precursor, the impact process is short, the duration is from several seconds to dozens of seconds, the coal explosion is generally shown, and the phenomenon of ground pressure impact is mostly shown as coal body throwing, and is accompanied by huge sound, rock mass vibration, shock waves and the like; the rock burst is very destructive, and often causes coal wall caving, roof sinking, bottom heaving, support damage, roadway blockage and casualties; the rock burst is frequently generated in a roadway, and the support strength and the density of a working face support are generally higher than those of two roadways, so that the rock burst is more easily generated in the two roadways of the working face and a driving roadway.
In order to prevent rock burst from endangering the safety production of coal mines, the roadway support by adopting the hydraulic support becomes an important means. The upright column is used as a main bearing part of the hydraulic support, and under the action of a huge load of instantaneous rock burst, the hydraulic lock is difficult to open and relieve pressure in time, so that the upright column is often expanded, exploded and damaged, and at the moment, the hydraulic support also loses the supporting capacity for the top plate, and further roadway deformation is caused. Therefore, the Liaoning engineering technology university and Beijing Chengtian constant industry coal mine equipment Limited company apply for a hydraulic prop patent (publication number CN102606177A) for a hydraulic support system in 2012, and invent an anti-impact prop with an energy-absorbing abdicating function. However, in this patent document, the energy-absorbing and impact-preventing portion is located at the lower portion of the impact-preventing pillar, the bottom of the plunger body and the energy-absorbing transition section are in a sleeved connection, the connection strength is weak, and the bottom of the plunger body and the energy-absorbing transition section are easily separated when the pillar is subjected to a certain load. Furthermore, in the patent document, an installation space of the energy-absorbing impact-preventing abdicating member and an abdicating space of the energy-absorbing transition section need to be reserved in the axial direction of the upright column, so that a larger axial dimension of the upright column is occupied, and the stroke of the impact-preventing upright column is influenced.
Disclosure of Invention
Therefore, in order to improve the stroke of the upright column and the bearing capacity of the hydraulic anti-impact upright column, the invention provides the solid-liquid coupling energy-absorbing anti-impact upright column.
In order to achieve the purpose, the invention adopts the following technical scheme:
a solid-liquid coupling energy-absorbing impact-proof upright column comprises an outer cylinder body and a movable cylinder body, wherein one end of the outer cylinder body is open, the other end of the outer cylinder body is fixedly connected with a cylinder bottom in a sealing mode, the movable cylinder body extends into an inner cavity of the outer cylinder body from the open end of the outer cylinder body, a liquid inlet communicated with the inner cavity of the outer cylinder body is further formed in the side wall of the outer cylinder body, a bottom piston is further arranged in the inner cavity of the outer cylinder body, an energy absorber is further arranged on one side, facing the cylinder bottom, of the bottom piston and is in contact with the bottom surface of the inner cavity of the cylinder bottom, a moving area for enabling the bottom piston to slide towards the direction of the cylinder bottom along the axial direction of the bottom piston is further arranged on the inner side wall of the outer cylinder body and/or the cylinder bottom, and the bottom piston and the outer cylinder body and/or the cylinder bottom form sliding fit with sealing in the moving area range; the liquid inlet is arranged close to the bottom piston and is positioned between the bottom piston and the movable column body.
The stand is single stand or two flexible stands, when being two flexible stands, is located in the outer cylinder body inner chamber the end of the post that lives installs the bottom valve, install on the bottom piston with the ejector pin that the bottom valve corresponds is used for the back-open the bottom valve.
Furthermore, the ejector rod penetrates through two round surfaces of the bottom piston and is fixedly connected with the cylinder bottom, and sliding fit with sealing is formed between the ejector rod and the bottom piston.
Furthermore, a communication hole communicated with the inner cavity of the cylinder bottom is also formed in the cylinder bottom.
Furthermore, the inner side surface of the outer cylinder body or the inner side surface of the cylinder bottom is also provided with a limiting structure for preventing the bottom piston from moving towards the direction far away from the cylinder bottom.
And a sealing ring is arranged between the cylinder bottom and the outer cylinder body.
The energy absorber is a metal anti-impact energy absorber, a gas energy absorber or a liquid energy absorber.
The technical scheme of the invention has the following beneficial effects:
A. in the upright column structure provided by the invention, only one bottom piston is arranged between the liquid working part of the inner cavity of the outer cylinder body and the energy absorber, the energy absorber is in close contact with the bottom piston, the energy absorber is positioned in the inner cavity of the cylinder bottom, the occupied space is small, the effective stroke of the upright column is increased, the bottom piston forms a moving area on the inner side surface of the outer cylinder body or the cylinder bottom, instantaneous high-pressure load acts on the bottom piston to enable the bottom piston to move along the moving area, the energy absorber absorbs load energy, the impact load acting on the live cylinder body is quickly absorbed and abducted instantaneously, the impact resistance of the impact-resistant upright column is improved, meanwhile, the upright column structure is compact, and the stroke of the impact-resistant upright column is increased.
B. The cylinder bottom and the outer cylinder body are connected in a detachable, fixed and sealed mode, when the anti-impact vertical column is used, relative movement does not exist between the cylinder bottom and the outer cylinder body, the connection strength is high, and the axial load bearing capacity of the anti-impact vertical column can be improved.
C. According to the invention, the energy absorber is arranged in the closed cylinder bottom inner cavity, so that sparks generated in the deformation process of the energy absorber can be effectively isolated from combustible gas outside the anti-impact upright post, and the overall explosion-proof performance is improved.
Drawings
In order to more clearly illustrate the embodiments of the present invention, the drawings which are needed to be used in the embodiments will be briefly described below, and it is apparent that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained from the drawings without inventive labor to those skilled in the art.
FIG. 1 is a schematic view of a single-upright anti-impact upright structure provided by the present invention;
fig. 2 is a schematic structural view of a double-telescopic anti-impact upright column provided by the invention.
Description of reference numerals:
1-external cylinder body, 11-liquid inlet, 12-hydraulic lock; 2-a living cylinder; 3-cylinder bottom, 31-communicating hole; 4-bottom piston; 5-an energy absorber; 6-bottom valve; 7-a mandril; a-the moving area.
Detailed Description
The technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings, and it should be understood that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the system or element being referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.
The invention provides a solid-liquid coupling energy-absorbing impact-proof upright post which is of a single upright post structure as shown in figure 1, the impact-proof upright post mainly comprises an outer cylinder body 1 and a movable column body 2, one end of the outer cylinder body 1 is opened, the other end of the outer cylinder body is sealed by connecting a cylinder bottom 3, namely, the extending side of the non-movable cylinder body is sealed, the cylinder bottom 3 and the outer cylinder body 1 preferably adopt a detachable sealing fixed connection mode, the energy absorber 5 in the cylinder bottom 3 is convenient to replace, the movable cylinder body 2 extends into the inner cavity of the outer cylinder body 1 from the opening end of the outer cylinder body 1, a movable sealing element is arranged between the movable cylinder body 2 and the outer cylinder body 1, the liquid pressure in the outer cylinder body 1 can be ensured to act on the piston of the movable cylinder body 2, the side wall of the external cylinder body 1 is also provided with a liquid inlet 11 communicated with the inner cavity of the external cylinder body, the liquid inlet 11 is connected with an external hydraulic lock 12, and the liquid in the inner cavity of the external cylinder body 1 can be sealed through a safety valve on the hydraulic lock 12. A bottom piston 4 is further arranged in an inner cavity at the other end of the outer cylinder body 1, in the figure, the bottom piston 4 is arranged close to the lower end of the outer cylinder body 1, an energy absorber 5 is further fixed at the lower end face of the bottom piston 4, the energy absorber 5 is in contact with the bottom surface of the inner cavity of the cylinder bottom 3, a moving area a for the bottom piston 4 to slide towards the direction of the cylinder bottom 3 along the axial direction of the inner side wall of the outer cylinder body 1 and/or the cylinder bottom 3 is further arranged on the inner side wall of the outer cylinder body 1 and/or the cylinder bottom 3, the bottom piston 4 and the outer cylinder body 1 form sliding fit with sealing in the moving area a, and the moving area a can also be arranged on the inner cylindrical surface of the cylinder bottom 3; the liquid inlet 11 is disposed near the bottom piston 4 and between the bottom piston 4 and the plunger 2, i.e. the liquid inlet 11 is located near the upper end surface of the bottom piston 4 and above the sealing band of the outer cylindrical surface of the bottom piston 4 in fig. 1. The edge of the bottom piston 4 forms a sealing fit with the inner cylindrical surface of the outer cylinder body 1 or the cylinder bottom 3, and the bottom piston 4 can slide along the axis of the outer cylinder body 1 relative to the outer cylinder body 1.
After the anti-impact upright post forms a support, the liquid pressure in the outer cylinder body 1 acts on the bottom piston 4, the bottom piston 4 presses on the energy absorber 5, and a structure that the upper part of the bottom piston 4 is supported by high-pressure liquid, the lower part of the bottom piston is supported by the energy absorber 5, and the upper and lower supporting parts are connected in series is formed. When the anti-impact upright post is loaded at a low speed, if the load is greater than the working resistance of the anti-impact upright post, the internal liquid pressure of the anti-impact upright post is higher than the set pressure of a safety valve 12 of a hydraulic lock matched with the anti-impact upright post, the safety valve 12 of the hydraulic lock is opened to release pressure, and high-pressure liquid in the inner cavity of the outer cylinder body 1 is discharged from a liquid inlet 11 and is discharged from the safety valve 12 of the hydraulic lock, so that the internal working resistance of the anti-impact upright post is ensured to be recovered to the working pressure state before overload; when scour protection stand caused scour protection stand inner chamber liquid pressure to exceed 12 relief valves of hydraulic pressure lock and set for opening pressure by the effect of high-speed impact load, because scour protection stand hydraulic pressure lock 12 relief valves can't in time open in the twinkling of an eye, cause liquid pressure further increase, the axial force of effect on end piston 4 and energy absorber 5 will be greater than the working resistance of scour protection stand, when the axial force is greater than 5 start-up holding power of energy absorber, energy absorber 5 begins quick energy-absorbing and steps down, end piston 4 is along removing regional a lapse, the protection scour protection stand can not further overload and damage, and then hydraulic support's effective holding power has been kept.
The scour protection stand that fig. 2 shows is two flexible stand structures, and 2 tip of the cylinder body that lives that are located in the outer cylinder body 1 inner chamber install bottom valve 6, and the lower extreme department that has the cylinder body structure that lives of two flexible functions in the picture promptly is provided with bottom valve 6, installs the ejector pin 7 corresponding with bottom valve 6 on the bottom piston 4 for back-open bottom valve 6. In the invention, the push rod 7 preferably penetrates through two circular surfaces of the bottom piston 4, namely the upper end surface and the lower end surface of the bottom piston 4, the lower end of the push rod 7 is contacted with the bottom surface of the inner cavity of the cylinder bottom 3, preferably, the push rod 7 is fixedly connected with the cylinder bottom 3, and the push rod 7 is in slidable sealing fit with a through hole penetrating through the bottom piston 4.
When the upright post needs to be contracted, the bottom valve 6 moves downwards to the upper end face of the bottom piston 4, and the valve core of the bottom valve 6 is pushed open by the upper end of the ejector rod 7 due to the relative fixation of the position of the ejector rod 7, so that the bottom valve 6 is opened, and the liquid in the secondary inner cavity of the double-telescopic upright post is communicated with the inner cavity of the outer cylinder body, thereby realizing the contraction of the primary cylinder body, the secondary cylinder body and the movable post. Since the double telescopic shock-proof upright posts are the prior art, the working principle thereof will not be further described in detail here.
When scour protection stand caused scour protection stand inner chamber liquid pressure to exceed 12 safety valve opening pressure of hydraulic pressure lock when receiving the high-speed impact load effect, because scour protection stand hydraulic pressure lock 12 safety valve can't in time open in the twinkling of an eye, cause liquid pressure further increase, the axial force of effect on end piston 4 and energy absorber 5 will be greater than the working resistance of scour protection stand, when the axial force is greater than 5 start-up holding power of energy absorber, energy absorber 5 begins quick energy-absorbing and steps down, end piston 4 is along removing regional a lapse, the protection scour protection stand can not further overload and damage, and then hydraulic support's effective holding power has been kept.
As shown in figure 2, the invention also has a communicating hole 31 communicated with the inner cavity of the cylinder bottom 3 on the cylinder bottom 3, the communicating hole 3 can keep the air pressure in the inner cavity of the cylinder bottom 3 communicated with the outside atmosphere, when instantaneous high-pressure impact is generated, the effect of discharging the air in the cylinder bottom 3 to balance the internal pressure and the external pressure is achieved, of course, the impact detection can also be carried out through the communicating hole 3.
In order to prevent the bottom piston 4 from moving in a direction away from the cylinder bottom 3, a limiting structure (not shown in the figure) is further arranged on the inner side surface of the outer cylinder body 1 or the inner side surface of the cylinder bottom 3, the limiting structure can be a stop, a check ring, a limiting protrusion or the like, and the limiting structure is arranged above the bottom piston.
The energy absorber 5 used in fig. 1 and 2 of the present invention is a metal impact-resistant energy absorber, a gas energy absorber or a liquid energy absorber.
The cylinder bottom and the outer cylinder body are fixedly connected in a detachable mode, the sealing ring is arranged between the cylinder bottom and the outer cylinder body, no relative movement exists between the cylinder bottom and the outer cylinder body when the cylinder bottom and the outer cylinder body are used, the connecting strength is high, and the capability of the upright column for bearing axial tensile load can be improved.
According to the invention, the energy absorber 5 is arranged in the inner cavity of the closed cylinder bottom 3, so that sparks generated in the deformation process of the energy absorber can be effectively isolated from combustible gas outside the anti-impact upright post, and the overall explosion-proof performance is improved.
It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications therefrom are intended to be within the scope of the invention.
Claims (7)
1. The solid-liquid coupling energy-absorbing impact-proof upright column comprises an outer cylinder body (1) and a movable cylinder body (2), wherein one end of the outer cylinder body (1) is opened, a sealed fixed connection is formed between the other end of the outer cylinder body and a cylinder bottom (3), the movable cylinder body (2) is extended into an inner cavity of the outer cylinder body (1) through an opening end of the outer cylinder body (1), a liquid inlet (11) communicated with the inner cavity of the outer cylinder body is further formed in the side wall of the outer cylinder body (1), a bottom piston (4) is further arranged in the inner cavity of the outer cylinder body (1), an energy absorber (5) is further arranged on one side, facing the cylinder bottom (3), of the bottom piston (4), and the energy absorber (5) is in contact with the bottom surface of the inner cavity of the cylinder bottom (3), the outer cylinder body (1) and/or the inner side wall of the cylinder bottom (3) is further provided with a moving area (a) for enabling the bottom piston (4) to slide towards the direction of the cylinder bottom (3) along the axis direction, the bottom piston (4) forms a sliding fit with a seal with the outer cylinder body (1) and/or the cylinder bottom (3) within the range of the moving area (a); the liquid inlet (11) is arranged close to the bottom piston (4) and is positioned between the bottom piston (4) and the movable column body (2).
2. The solid-liquid coupling energy-absorbing impact-proof upright post according to claim 1, wherein the upright post is a double-telescopic upright post, a bottom valve (6) is installed at the end part of the movable post body (2) in the inner cavity of the outer cylinder body (1), and a top rod (7) corresponding to the bottom valve (6) is installed on the bottom piston (4) and used for jacking the bottom valve (6).
3. The solid-liquid coupling energy-absorbing impact-preventing upright post according to claim 2, wherein the ejector rod (7) penetrates through two circular surfaces of the bottom piston (4) and is fixedly connected with the cylinder bottom (3), and a sliding fit with a seal is formed between the ejector rod (7) and the bottom piston (4).
4. The solid-liquid coupling energy-absorbing impact-preventing upright post according to claim 3, characterized in that the cylinder bottom (3) is further provided with a communication hole (31) communicated with the inner cavity of the cylinder bottom (3).
5. The solid-liquid coupling energy-absorbing impact-preventing upright post according to any one of claims 1 to 4, wherein a limiting structure for preventing the bottom piston (4) from moving towards the direction away from the cylinder bottom (3) is further arranged on the inner side surface of the outer cylinder body (1) or the inner side surface of the cylinder bottom (3).
6. The solid-liquid coupling energy-absorbing impact-preventing upright post according to claim 5, characterized in that a sealing ring is arranged between the cylinder bottom (3) and the outer cylinder body (1).
7. The solid-liquid coupling energy-absorbing impact-proof upright post according to claim 1, characterized in that the energy absorber (5) is a metal impact-proof energy absorber, a gas energy absorber or a liquid energy absorber.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110877754.5A CN113482676A (en) | 2021-08-01 | 2021-08-01 | Solid-liquid coupling energy-absorbing scour protection stand |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110877754.5A CN113482676A (en) | 2021-08-01 | 2021-08-01 | Solid-liquid coupling energy-absorbing scour protection stand |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113482676A true CN113482676A (en) | 2021-10-08 |
Family
ID=77943928
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110877754.5A Pending CN113482676A (en) | 2021-08-01 | 2021-08-01 | Solid-liquid coupling energy-absorbing scour protection stand |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113482676A (en) |
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2021
- 2021-08-01 CN CN202110877754.5A patent/CN113482676A/en active Pending
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