Support system for advanced-section roadway of fully-mechanized coal mining working face gateway

Abstract

A support system for an advanced-section roadway of a fully-mechanized coal mining working face gateway. The support system comprises a downhole working face gateway (1), wherein an advanced-section roadway of the working face gateway is sequentially divided into a severely deformed area, a seriously deformed area and a moderately deformed area from inside to outside; and the severely deformed area is internally provided with advanced frame sets (2), each advanced frame set is internally provided with a plurality of unit supports (4) connected by means of connecting oil cylinders (6), and a middle-section unit support (5) connected to side unit supports by means of connecting oil cylinders is provided between every two advanced frame sets.

Description

A comprehensive mechanized coal mining face tunnel leading section support system

[0001] This application claims priority to the Chinese patent application filed with the Patent Office of China on December 29, 2023, with application number CN202311840213.0 and application name “A comprehensive mechanized coal mining working face chute advance section tunnel support system”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of coal mine comprehensive mining advance support, and specifically to a comprehensive mechanized coal mining working face drift advance section roadway support system. Background Art

[0003] At present, the comprehensive mechanized longwall retreat mining method is developing rapidly. Its main feature is to mine the entire height at one time and use the full caving method to deal with the goaf roof. In order to prevent the working face chute roof from sinking during underground mining, it is necessary to carry out advance support in the mining working face chute. In the existing technology, advance supports are used for support. The advance support consists of two sets of ZCZ15000 / 25 / 42D advance support groups. The maximum support height of the advance support is 4200mm, the total width is 3560mm, and the support length is 21.5m. The advance support retreats as the working face moves forward.

[0004] However, when mining under the following special conditions (as shown in Figure 11):

[0005] 1. During the mining process, due to changes in geological conditions, 24106 was located in a scour zone, which was not conducive to surrounding rock control and easily led to roof subsidence and floor deformation. 2. Due to the combined effects of the leading support pressure of the 24106 working face and the lateral support pressure of the 24107 goaf, the leading influence range and stress value of the 24106 working face increased. 3. Due to the impact of mining on the 24106 working face, the roof separation area of ​​the drift roadway was activated and sank. During the overall roof subsidence, pressure was transmitted from the two sides to the floor, causing significant floor deformation.

[0006] Specifically, the mine pressure is most severe within 20m of the advance working face, with large roof subsidence (maximum 200mm) and severe tunnel floor heave (floor heave exceeding 600mm); within 20m~50m of the advance working face, the mine pressure is relatively serious, with tunnel floor heave reaching 300mm and a certain degree of roof subsidence; within 50m~80m of the advance working face, the mine pressure tends to ease, with smaller tunnel roof subsidence, but a certain degree of floor heave still occurs (maximum floor heave reaching 150mm); after 80m of the advance working face, the overall deformation of the tunnel is small and is almost unaffected by mining.

[0007] For the large-scale deformation area of ​​the above-mentioned underground working face chute advance (the advance impact range of the 24106 working face chute is about 50m), the existing advance support (advance frame group support distance is 21.6m) is not enough for support and protection, and the advance support of the working face chute adopts a step-by-step moving method from the inside to the outside and moves forward with the working face. The advance support repeatedly supports the roof during the movement, which can easily destroy the integrity and stability of the tunnel roof. In addition, the large-scale deformation area also leads to insufficient height of the working face end, resulting in the problem of artificial bottoming due to insufficient safety gap between the end frame and the conveyor. Summary of the Invention

[0008] In order to solve the above-mentioned problems, the present application provides a comprehensive mechanized coal mining face drift advance section tunnel support system.

[0009] This application is implemented through the following technical solutions:

[0010] A comprehensive mechanized coal mining face drift leading section roadway support system includes an underground working face drift, wherein the working face drift leading section roadway is divided into a severe deformation zone, a serious deformation zone and a moderate deformation zone from the inside to the outside;

[0011] Multiple advance frame groups connected by push-pull cylinders are set in the severe deformation area. Multiple unit supports connected by connecting cylinders are set in the middle empty top of each advance frame group. A middle unit support connected to the side unit support by connecting cylinders is set between the two advance frame groups. The advance frame group and the unit support, and the retreat frame of the middle unit support in the severe deformation area are always maintained with the advance section top plate support;

[0012] In the advanced section of the roadway in the severely deformed area along the mildly deformed area, a row of multiple independent unit supports facing the center of the advanced frame group are set for support.

[0013] Further optionally, the advance frame group includes multiple hinged base frames on both sides of the bottom, the upper part of the base frame is connected and supported with the corresponding top beam by multiple hydraulic columns, and the two base frames and the outer ends of the top beam are laterally connected by an adjusting cylinder.

[0014] Further optionally, the unit bracket inside the advance frame group is also provided with a stabilizing support device, which is supported on the bottom frame of the advance frame group for stable support when the unit bracket is moved.

[0015] Further optionally, the stabilizing support device includes two support arms hingedly arranged on both sides of the unit bracket base, the lower part of each support arm is hingedly fixed to the unit bracket base through a support cylinder, and the outer end of the support arm is connected to a support block supported on the inner edge of the base frame.

[0016] Further optionally, the support arm is arranged as a telescopic arm and is fixed by plugging through a pin shaft, and a plurality of rotation grooves are provided on the upper inner side of the chassis of the advance frame group, and a supporting rolling body is provided in each rotation groove.

[0017] Further optionally, an anti-collapse device is provided on the side of the independent unit bracket, which includes an anti-collapse chain connected to both sides of the upper top beam of the independent unit bracket, and the outer end of the anti-collapse chain is connected and fixed to the anchor cap at the end of the anchor rod set on the tunnel top plate.

[0018] Further optionally, an adjusting bolt for adjusting the tightness of the anti-fall chain is installed on the anti-fall chain.

[0019] Further optionally, an offset warning device for lateral displacement of the independent unit bracket is provided at the connection between the anchor cap and the anti-fall chain. The offset warning device includes a frame connected to the lower part of the anchor cap, a mounting sleeve is screwed at the bottom opening of the frame, a gas cylinder extending to the inside of the frame is provided in the mounting sleeve, a bursting disc is installed on the exhaust pipe at the bottom of the gas cylinder, and an alarm whistle connected to the exhaust pipe outlet is provided at the lower part of the bursting disc.

[0020] Further optionally, a stirrup buckle connected to the outer end of the anti-fall chain is passed through the frame, and the inner side of the stirrup buckle is fitted with the side wall of the gas cylinder.

[0021] Further optionally, the unit brackets inside the advance frame group and the cylinder columns of the middle unit brackets are connected to the hydraulic reversing valve of the advance frame group itself through hydraulic pipelines, the hydraulic reversing valve is electrically connected to the hydraulic valve driver, and the hydraulic valve driver is electrically connected to the bracket controller.

[0022] Compared with the existing technology, the beneficial effects of this application are:

[0023] 1. The implementation of this solution can significantly reduce the dynamic damage to the top plate caused by repeated lifting and lowering of the advance frame group during frame moving. The internal unit brackets remain in a supporting state during the moving, lowering and raising of the advance frame group. The advance frame group remains in a supporting state during the moving of the unit brackets. The top plate of the advance section remains in a supported state during the moving period. There is no obvious change in internal stress, and the top plate will not be damaged by the repeated support of the advance frame group during the moving.

[0024] 2. The alternating shifting of the advance frame group and the unit support realizes the support of the advance section of the working face end without weak links, reduces the sinking of the top plate when it is in a state without passive support during the shifting period, and avoids the problem of insufficient safety gap between the end frame and the conveyor due to insufficient end height, which requires manual landing.

[0025] 3. The multiple unit supports within the range of the advance frame group are transformed into step-type self-moving ones. The hydraulic system of the unit support is connected to the electro-hydraulic control of the advance frame group to realize automatic control of one frame, which reduces the workload of moving the frame and improves safety.

[0026] 4. The length and strength of the advance support are increased, which effectively controls the floor heave caused by pressure conduction in the goaf, and avoids the situation where the roof pressure exceeds the design range when the working face is pushed to a special geological structure area, resulting in insufficient strength of the advance support, causing the roof pressure at both ends of the working face to crush the advance frame or cause a roof collapse.

[0027] 5. The support of the independent unit bracket is safer and more reliable, ensuring the safety of the operating space around the independent unit bracket and greatly reducing the safety risks caused by the side tilt of the independent unit bracket. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] FIG1 is a schematic diagram of a system arrangement provided in an embodiment of the present application;

[0029] FIG2 is a schematic diagram of the three-dimensional structure of the advance frame group and the unit bracket provided in an embodiment of the present application;

[0030] FIG3 is a schematic diagram of another state of the advance rack group and the unit bracket provided in an embodiment of the present application;

[0031] FIG4 is a schematic enlarged view of the local structure of FIG3;

[0032] FIG5 is a schematic structural diagram of a support arm of a unit bracket provided in an embodiment of the present application;

[0033] FIG6 is a schematic structural diagram of an independent unit bracket in use according to an embodiment of the present application;

[0034] FIG7 is a schematic diagram of the three-dimensional structure of the alarm device in FIG6;

[0035] FIG8 is a schematic diagram of the installation structure of the bursting disc in FIG7;

[0036] FIG9 is a schematic diagram of an independent unit bracket moving frame provided in an embodiment of the present application;

[0037] FIG10 is a diagram of a hydraulic control system for an advance frame group and a unit support provided in an embodiment of the present application;

[0038] FIG11 is a schematic diagram of the prior art;

[0039] In the figure: 1. Working face chute; 2. Advance frame group; 201. Underframe; 202. Hydraulic column; 203. Top beam; 204. Adjustment cylinder; 205. Rolling element; 3. Push-pull cylinder; 4. Unit bracket; 5. Middle unit bracket; 501. Support arm; 502. Support cylinder; 503. Support block; 504. Pin; 6. Connecting cylinder; 7. Independent unit bracket; 8. Anti-fall chain; 9. Adjustment Joint bolt; 10. Anchor rod; 11. Deflection warning device; 12. Frame; 13. Mounting sleeve; 14. Gas cylinder; 15. Exhaust pipe; 16. Bursting disc; 17. Alarm whistle; 18. Inflating port; 19. Stirrup buckle; 20. Anchor rod cap; 21. Hydraulic reversing valve; 22. Hydraulic valve driver; 23. Bracket controller; 24. Pipeline; 25. Wire rope; 26. Pneumatic winch; 27. Equipment train. DETAILED DESCRIPTION

[0040] The present application is further described in detail below with reference to the accompanying drawings and specific embodiments:

[0041] As shown in Figure 1, a comprehensive mechanized coal mining face tunnel advance section roadway support system includes an underground working face tunnel 1. The leading section of the working face tunnel 1 is divided into a severe deformation zone, a serious deformation zone, and a moderate deformation zone from the inside to the outside. The severe deformation zone is characterized by large roof subsidence (maximum 200mm) and severe roadway floor heave (floor heave exceeding 600mm); the serious deformation zone is within the range of 20m to 50m from the leading working face, where the mine pressure is relatively severe, the roadway floor heave reaches 300mm, and the roof sinks to a certain extent; the moderate deformation zone is within the range of 50m to 80m from the leading working face, where the mine pressure tends to be moderate, the roadway roof subsidence is small, and a certain degree of floor heave still occurs (maximum floor heave reaches 150mm);

[0042] The division of the above areas can also be adjusted based on the actual data on site. In this way, different bracket combinations can be used to support the deformation zones divided according to different deformation amounts. Under the premise of ensuring the stability of the support, the use of advanced brackets can be minimized (advanced brackets are bulky and occupy a large space and are more difficult to move). Different areas have better adaptability to different combinations of brackets and brackets.

[0043] Example 1:

[0044] As shown in Figures 1 and 2, a plurality of advance frame groups 2 connected by push-pull cylinders 3 are provided in the severe deformation area. The two advance frame groups 2 are connected by the push-pull cylinders 3 to achieve step-by-step self-movement. The overall length of the two advance frame groups and the push-pull cylinders 3 is 21.6m, which can completely cover the entire severe deformation area. A plurality of unit brackets 4 connected by connecting cylinders 6 are provided in the middle empty top of each advance frame group 2. Two brackets can be supported in the middle of the left and right support parts of each group of advance frame groups. The bases of the two unit brackets 4 within the range of the same advance frame group are connected by a 1.2m push-pull cylinder 3 to enable them to achieve step-by-step self-movement.

[0045] A middle section unit support 5 connected to the side unit support 4 by a connecting cylinder 6 is provided between the two advance frame groups 2. The base of the middle section unit support 5 is connected to the outer unit support 4 by a 1.4m oil cylinder to realize the support of the empty top area at the junction of the advance frame group 2. When the advance frame group 2 and the unit support 4 and the middle section unit support 5 in the severe deformation area are moved backward, one of the support groups always maintains support with the advance section top plate. This can significantly reduce the dynamic damage to the top plate caused by repeated lifting and lowering when the advance frame group 2 is moved. The internal unit supports remain in a supporting state during the movement, lowering and raising of the advance frame group 2. The advance frame group 2 remains in a supporting state during the movement of the unit supports. The top plate of the advance section roadway remains in a supporting state during the movement, and the internal stress does not change significantly. The top plate will not be damaged by the repeated support of the advance frame group when moving.

[0046] In the advanced section of the roadway in the severe deformation area along the deformation relaxation area, a row of multiple independent unit supports 7 are set up facing the center of the advanced frame group for support. The independent unit supports 7 are supported between the advanced frame group 2 and the equipment train 27 in the deformation relaxation area. A total of 16 frames are supported, and the center distance of the supports is 2.5m. The overall support length is 40 meters. They are supported along the roadway direction at the center facing the advanced frame group 2, and the distance from the edge of the base to the production side is not less than 1600mm. This increases the length of the advanced support, effectively controls the bottom heave caused by pressure conduction in the goaf, reduces the workload of manual landing, and avoids the tilt of the advanced frame due to the influence of bottom heave.

[0047] The advance frame group 2 includes multiple hinged base frames 201 on both sides of the bottom. The upper part of the base frame 201 is connected and supported by multiple hydraulic columns 202 and the corresponding top beams 203. The two base frames 201 and the outer ends of the top beam 203 are connected laterally by adjusting cylinders 204. The adjusting cylinders 204 at the top and bottom of the advance frame group 2 are retracted to the shortest to ensure that the distance between the bases of the left and right support parts of the advance frame group 2 is no more than 1.2m. This can enable the five unit supports 5 and the middle unit support 5 within the advance range to form a whole, which is conducive to preventing the middle unit support 5 from skewing (the unit support 5 is arranged separately without support);

[0048] Example 2:

[0049] As shown in Figures 3 and 4, the unit bracket 4 on the inner side of the advance frame group 2 is also provided with a stabilizing support device, which supports the unit bracket 4 on the bottom frame 201 of the advance frame group 2 for firm support when the unit bracket 4 is moved, so that the unit bracket 4 is not easy to tilt when it is not supported by force on the tunnel roof (in a free state).

[0050] The stabilizing support device includes two support arms 501 hingedly arranged on both sides of the base of the unit bracket 4. The lower part of each support arm 501 is hingedly fixed to the base of the unit bracket 4 through a support cylinder 502. The outer end of the support arm 501 is connected to a support block 503 supported on the inner edge of the base frame 201. When the unit bracket 4 is used to support the top plate, the support cylinder 502 is started by operation to lift the support arm 501 and fit it to the side of the unit bracket 4 to avoid taking up space. When the unit bracket 4 is moved, the support arm 501 is expanded by the support cylinder 502 to support the side edge of the advance frame group 2, thereby achieving stable support for the unit bracket 4. This not only eliminates the need to shrink the width of the advance frame group 2, but also greatly improves the range of the advance frame group 2's support area for the top plate, and can always keep the unit bracket in the center position of the advance frame group 2, so that the overall force on the top plate support is more uniform, and there is no need for additional position adjustment of the hydraulic support.

[0051] As shown in Figures 4 and 5, the support arm 501 is set as a telescopic arm and is fixed by a pin shaft 504. The length of the support arm 501 can be adjusted by the pin shaft 504 to adapt to the advance frame group 2 of different widths. A plurality of rotating grooves are provided on the upper inner side of the base frame 201 of the advance frame group 2, and a supporting rolling body 205 is provided in each rotating groove. The rolling body 205 facilitates the rapid movement of the unit bracket 4.

[0052] Example 3:

[0053] As shown in Figure 6, an anti-fall device is provided on the side of the independent unit bracket 7, which includes an anti-fall chain 8 connected to both sides of the upper top beam of the independent unit bracket 7. The anti-fall chain 8 is made of 5t anchor chain, and the outer end of the anti-fall chain 8 is connected and fixed to the anchor cap 20 at the end of the anchor rod 10 set on the tunnel roof. An adjusting bolt 9 for adjusting its tightness is installed on the anti-fall chain 8. In this way, the anti-fall chains 8 on both sides of the independent unit bracket 7 can avoid tilting, thereby improving the stability of the independent unit bracket 7 without the advance frame group 2 in the severe deformation area.

[0054] As shown in Figures 6 and 7, an offset warning device 11 for lateral displacement of the independent unit bracket 7 is provided at the connection between the anchor cap 20 and the anti-fall chain 8. The offset warning device 11 includes a frame 12 connected to the lower part of the anchor cap 20, and a mounting sleeve 13 is screwed at the bottom opening of the frame 12. A gas cylinder 14 extending to the inside of the frame 12 is provided in the mounting sleeve 13, and a bursting disc 16 (as shown in Figure 8) is installed on the exhaust pipe 15 at the bottom of the gas cylinder 14. The lower part of the bursting disc 16 is provided with an alarm whistle 17 connected to the outlet of the exhaust pipe 15.

[0055] When the independent unit bracket 7 tilts locally while supporting, the anti-fall chain 8 on the other side of the tilt direction will be pulled by the stirrup buckle 19 to squeeze the gas cylinder 14 of the offset warning device 11. The gas cylinder 14 is deformed by the force and the internal gas pressure rises sharply to reach the bursting pressure set by the bursting piece 16. The bursting piece 16 breaks open and the exhaust pipe 15 opens. In this way, the gas in the gas cylinder 14 quickly rushes to the alarm whistle 17 at the bottom, causing the alarm whistle 17 to sound an alarm, thereby reminding the surrounding personnel to quickly move away from the area and readjust the support of the independent unit bracket 7 to ensure the safety of the surrounding operating space, greatly reducing the safety risks brought by the tilting of the independent unit bracket 7, and the gas cylinder 14 can also buffer the impact of the stirrup buckle 19 directly on the anchor cap 20, causing the end of the anchor 10 to be directly damaged by the impact.

[0056] Depending on the on-site conditions, the pressure of the bursting disc 16 can be set to 2 bar, and the gas volume in the gas cylinder 14 can be 1.5-1.8 bar, to ensure that the bursting disc 16 is blown open after the gas cylinder 14 is deformed by force. At the same time, the gas in the gas cylinder 14 uses nitrogen, which is relatively safe. The material of the gas cylinder 14 can be made of metal or polytetrafluoroethylene. The polytetrafluoroethylene gas cylinder 14 can be recycled and used after being refilled through the filling port 18.

[0057] A stirrup buckle 19 connected to the outer end of the anti-fall chain 8 is passed through the frame 12, and the inner side of the stirrup buckle 19 is fitted with the side wall of the gas cylinder 14. The adjusting bolt 9 on the anti-fall chain 8 can always maintain a tensioned state to ensure that the stirrup buckle 19 fits the side wall of the gas cylinder 14.

[0058] As shown in Figure 10, the cylinder columns of the unit bracket 4 and the middle unit bracket 5 inside the advance frame group 2 are connected to the hydraulic reversing valve 21 of the advance frame group 2 itself through the hydraulic pipeline 24, the hydraulic reversing valve 21 is electrically connected to the hydraulic valve driver 22, and the hydraulic valve driver 22 is electrically connected to the bracket controller 23. The hydraulic systems of multiple frame unit brackets within the range of the advance frame group 2 are connected to the hydraulic control system of the advance frame group to realize automatic control of one frame, reduce the workload of frame moving, and improve safety.

[0059] Working principle:

[0060] When the working face is retreating, the advance support of the drift needs to be moved and retreated along with the working face;

[0061] 1. Unit bracket 4, middle unit bracket 5 moving rack

[0062] (1) First lower the outer unit support 4 close to the working surface. When lowering the unit support 4, the support worker operates the electro-hydraulic control of the advance frame group. During the lowering process, no one is allowed to stand within 5m. Pay attention that people are not allowed to stand in the direction of the valve port to prevent the unit support from tipping over or backflowing liquid to injure people during the lowering process.

[0063] (2) The frame must be lowered to the lowest height of the bracket. After reaching the lowest height, the lowering operation is completed.

[0064] (3) After the frame is lowered, the connecting cylinder 6 connected to the base of the two unit brackets 4 is used to move the bracket to the specified step distance (0.8m).

[0065] (4) Raise the unit bracket 4 to support the top plate. After raising the bracket, the bracket should be tightly connected to the top, and the initial support force of the unit bracket should reach more than 11.5MPa.

[0066] (5) Repeat the above steps, pull the rear unit bracket to the specified step distance, and move the middle unit bracket 5 and the connected unit bracket 4 according to the above steps and principles.

[0067] 2. Move the independent unit bracket 7 in the severely deformed area (as shown in Figure 9)

[0068] After the equipment train is moved, the first independent unit support 7 close to the working surface is promptly moved to the outermost side and re-supported. The specific process flow is as follows:

[0069] (1) Before lowering the unit bracket, the anti-fall chain 8 is manually removed through the stirrup buckle 19. When lowering the bracket, the bracket worker operates the hydraulic manual valve handle to lower the bracket. Note that personnel must not stand in the direction of the valve port to prevent the unit bracket from tipping over or backflowing when lowering the bracket.

[0070] (2) The frame is lowered to the lowest height of the independent unit bracket 7. After reaching the lowest height, the frame lowering operation is completed.

[0071] (3) After the lowering is completed, the independent unit bracket 7 is pushed sideways and adjusted to the side of the pedestrian road using a single hydraulic support.

[0072] (4) A five-point rope (φ15.5) is hung above the top plate of the towing route of the independent unit bracket 7. During towing, the top beam of the independent unit bracket 7 is connected to the upper wire rope through a special towing anti-fall rope (with stirrup buckles at both ends) to prevent it from falling.

[0073] (5) Use the JQHS-50X12 pneumatic winch 26 in conjunction with the return pulley to connect the wire rope to the lifting rings on both sides of the unit support base, and drag the unit support to the vicinity of the equipment train, 2.5m away from the outermost unit support.

[0074] (6) Use the single hydraulic support to adjust the independent unit support 7 to the predetermined support position.

[0075] (7) Raise the bracket to support the top plate. After raising the bracket, the bracket should be tightly connected to the top, and the initial support force of the unit bracket should reach more than 11.5MPa.

[0076] (8) After the bracket is raised, the anti-fall chain 8 of the independent unit bracket 7 should be connected in time to prevent it from falling.

[0077] 3. Moving the advance frame group: First, withdraw the independent unit bracket 7 in the severely deformed area, and support it to the outermost side close to the equipment train, then pull the inner unit bracket, and finally move the advance frame group one by one from front to back and from outside to inside.

[0078] (1) Operate the support controller 23 to lower the column so that the top beam 203 of the advance frame group 2 close to the working surface is slightly separated from the top plate;

[0079] (2) When the advance frame group 2 is movable, immediately stop lowering the hydraulic column 202, operate the push-pull cylinder 3 to pull the advance frame group 2 close to the working surface forward along the working surface, and move the advance frame group 2 to the specified step distance;

[0080] (3) Raise the hydraulic column 202 so that the main top beam of the advanced frame group 2 that has been moved is in close contact with the top plate and continue to supply fluid for 3 to 5 seconds to ensure that the initial support force reaches 88.5 kN (11.5 MPa);

[0081] (4) Repeat the above steps to move the other leading frame group 2 in a step-by-step manner.

[0082] The above shows and describes the basic principles, main features, and advantages of the present application. Those skilled in the art should understand that the present application is not limited to the above embodiments. The above embodiments and descriptions are merely illustrative of the principles of the present application. Various changes and improvements may be made to the present application without departing from the spirit and scope of the present application. These changes and improvements are intended to fall within the scope of the present application. The scope of protection claimed in this application is defined by the appended claims and their equivalents.

Claims

1. A roadway support system for the ultra-advanced section of the gate roadway in a fully mechanized coal mining face, including the underground working face gate roadway. The ultra-advanced section roadway of the working face gate roadway is divided into a severely deformed area, a seriously deformed area, and a mildly deformed area from inside to outside; In the severely deformed area, there are multiple sets of advanced supports connected by push-pull oil cylinders. Inside each set of advanced supports, there are multiple unit supports connected by connecting oil cylinders at the empty roof in the middle. Between the two sets of advanced supports, there is a middle section unit support connected to the side unit supports by connecting oil cylinders. The backward movement of the advanced supports, unit supports, and middle section unit supports in the severely deformed area always maintains the support for the ultra-advanced section roof; In the seriously deformed area, there is a row of multiple independent unit supports arranged opposite the center of the advanced support group along the ultra-advanced section roadway of the mildly deformed area for support.

2. The gateway pre-advanced roadway support system for fully mechanized coal mining face according to claim 1, wherein, Each set of advanced supports includes multiple bottom frames hinged on both sides at the bottom. The upper part of the bottom frame is connected and supported by multiple hydraulic columns to the corresponding roof beam. The outer ends of the two bottom frames and the roof beam are horizontally connected by an adjusting oil cylinder.

3. The gob-side entry driving roadway support system for the fully mechanized coal mining face according to claim 1, wherein, The unit support inside the set of advanced supports is also provided with a stable support device, which supports on the bottom frame of the advanced support group during the movement of the unit support for stable support.

4. The gob-side entry driving roadway support system for the fully mechanized coal mining face according to claim 3, wherein, The stable support device includes two support arms hinged on both sides of the unit support base. The lower part of each support arm is hinged and fixed to the unit support base by a support oil cylinder. The outer end of the support arm is connected with a support block supported on the inner edge of the bottom frame.

5. The gob-side entry driving roadway support system for the fully mechanized coal mining face according to claim 4, wherein, The support arm is arranged as a telescopic arm and is inserted and fixed by a pin shaft. There are several rotating grooves provided on the upper part of the inner side of the bottom frame of the set of advanced supports, and each rotating groove is provided with a rolling body for support.

6. The gob-side entry driving roadway support system for the fully mechanized coal mining face according to claim 1, wherein, The side of the independent unit support is provided with an anti-tipping device, which includes anti-tipping chains connected to both sides of the upper roof beam of the independent unit support. The outer ends of the anti-tipping chains are connected and fixed to the bolt caps at the ends of the bolts set on the roadway roof.

7. The gob-side entry driving roadway support system for the fully mechanized coal mining face according to claim 6, wherein, An adjusting bolt for adjusting its tightness state is installed on the anti-tipping chain.

8. The roadway support system for the ultra-advanced section of the gateway in the fully mechanized coal mining face according to claim 6, wherein, An offset early warning device for the side shift of the independent unit support is provided at the connection between the bolt cap and the anti-tipping chain. The offset early warning device includes a frame-shaped frame connected to the lower part of the bolt cap. A mounting sleeve is screwed at the bottom opening of the frame-shaped frame. An air cylinder extending to the inside of the frame-shaped frame is arranged in the mounting sleeve. A bursting disc is installed on the exhaust pipe at the bottom of the air cylinder. An alarm whistle connected to the outlet of the exhaust pipe is arranged below the bursting disc.

9. The gob-side entry driving roadway support system for the fully mechanized coal mining face according to claim 8, wherein, A stirrup buckle connected to the outer end of the anti-tipping chain is inserted into the frame-shaped frame, and the inner side of the stirrup buckle is arranged in contact with the side wall of the air cylinder.

10. The gob-side entry driving roadway support system for the fully mechanized coal mining face according to claim 1, wherein, The oil cylinder columns of the unit supports and the middle section unit supports between the sets of advanced supports are connected to the hydraulic reversing valve of the set of advanced supports itself through hydraulic pipelines. The hydraulic reversing valve is electrically connected to a hydraulic valve driver, and the hydraulic valve driver is electrically connected to a support controller.

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