阅读说明：本技术 一次性孔内充装二氧化碳致裂器及向钻孔中安装其的方法 (Disposable in-hole carbon dioxide fracturing device and method for installing same into drilled hole ) 是由 杨仁树 倪昊 于 2021-08-10 设计创作，主要内容包括：本发明实施例提供一种一次性孔内充装二氧化碳致裂器及向钻孔中安装其的方法,涉及爆破器材技术领域。二氧化碳致裂器包括：管体、发热棒、充装头、单向进气阀及外接气管,所述管体上设有泄能口,所述充装头连接在所述管体的开口端；所述充装头上设有用于向主管内部充装二氧化碳的充装通道,在所述充装通道中设有开启和关闭充装通道的单向进气阀,所述单向进气阀具有进气口与出气口,所述外接气管连接于所述单向进气阀的进气口上,所述出气口与所述管体的内部联通。在致裂器安装进钻孔内时,可以通过所述外接气管向致裂器的管体内部充装液态二氧化碳,相比现有技术中需要预先在孔外充装二氧化碳,便于提高二氧化碳致裂器使用时的安全性。(The embodiment of the invention provides a method for filling a carbon dioxide cracking device into a disposable hole and installing the carbon dioxide cracking device into the hole, and relates to the technical field of blasting equipment. The carbon dioxide fracturing device comprises: the heating device comprises a pipe body, a heating rod, a filling head, a one-way air inlet valve and an external air pipe, wherein an energy discharge port is formed in the pipe body, and the filling head is connected to the opening end of the pipe body; the filling head is provided with a filling channel for filling carbon dioxide into the main pipe, the filling channel is internally provided with a one-way air inlet valve for opening and closing the filling channel, the one-way air inlet valve is provided with an air inlet and an air outlet, the external air pipe is connected to the air inlet of the one-way air inlet valve, and the air outlet is communicated with the inside of the pipe body. When sending and splitting the ware installation and advancing in the drilling, can through external trachea fills liquid carbon dioxide to sending the body inside of splitting the ware, compare and need fill carbon dioxide in advance outside the hole among the prior art, be convenient for improve the security when carbon dioxide sends and splits the ware and uses.)

1. A disposable downthehole carbon dioxide that fills sends and splits ware which characterized in that includes:

the heating device comprises a tube body, a heating rod, a filling head, a one-way air inlet valve and an external air pipe, wherein one end of the tube body is a closed end, the other end of the tube body is an open end, an energy discharge port is formed in the tube body, and the filling head is connected to the open end of the tube body and seals the open end of the tube body;

fill and be equipped with the excellent installation department that generates heat on the head, the stick that generates heat includes: the base is installed in a heating rod installation part on the filling head, the paper tube is arranged in the tube body, the outer end of the paper tube is connected to the inner end of the base, the wiring terminal axially penetrates through the base, the first end of the wiring terminal extends out of the outer end of the base, the second end of the wiring terminal extends out of the inner end of the base and is arranged in the paper tube, the electric ignition head is connected to the second end of the wiring terminal, and heating agents are filled in the paper tube;

the filling head is also provided with a filling channel for filling carbon dioxide into the main pipe, the filling channel is internally provided with a one-way air inlet valve for opening and closing the filling channel, the one-way air inlet valve is provided with an air inlet and an air outlet, the external air pipe is connected to the air inlet of the one-way air inlet valve, and the air outlet is communicated with the inside of the pipe body.

2. The fracker of claim 1, wherein the filling passage comprises a first stage bore and a second stage bore, the first stage bore having a diameter greater than the second stage bore, an inner contour of the first stage bore corresponding to an outer contour of a valve body of the one-way intake valve, the one-way intake valve being mounted in the first stage bore, a first end of the second stage bore abutting an air outlet of the one-way intake valve, a second end of the second stage bore communicating with an interior of the tubular body.

3. The fracker of claim 1, wherein the vent is a slit axially disposed along an outer wall of the pipe body.

4. The cracker of claim 3 wherein the slits are linear elongate slits.

5. The splitter of claim 3 or 4, wherein the axial midpoint of the slit coincides with the midpoint of the tube.

6. The fracturing unit of claim 3 or 4, wherein the length of the slit is 1/3 mm, the width of the slit is 3-5 mm, and the depth of the slit is 1/5 mm of the wall thickness of the pipe body.

7. The fracker of claim 1, wherein the filling head is welded to the open end of the pipe body.

8. The fracker of claim 1, wherein the terminals comprise two terminals extending through the charging head in parallel, the second ends of the two terminals are connected to wires, and the ends of the two wires are connected to the electric ignition head.

9. The fracturing unit of claim 1, wherein the outer gas pipe is made of seamless steel pipe.

10. A method of installing a carbon dioxide cracker in a borehole, the method being carried out using the disposable borehole filled with a carbon dioxide cracker of any one of claims 1 to 9, the method comprising the steps of:

feeding the carbon dioxide fracker into a borehole; wherein the pipe body of the carbon dioxide cracking device is not filled with liquid carbon dioxide;

after the carbon dioxide cracking device is fed into the drill hole, connecting an external air pipe to an air outlet of carbon dioxide filling equipment, starting the carbon dioxide filling equipment, and filling liquid carbon dioxide into the external air pipe;

when the amount of liquid carbon dioxide flowing from the external air pipe to the air inlet of the one-way air inlet valve is increased to a preset amount, the channel of the one-way air inlet valve is automatically opened, and the liquid carbon dioxide enters the pipe body of the carbon dioxide cracking device until the inside of the carbon dioxide cracking device is filled to a preset pressure value.

Technical Field

The invention relates to the technical field of blasting equipment, in particular to a disposable hole carbon dioxide cracking device and a method for installing the same in a drilled hole.

Background

The carbon dioxide cracking device is a novel blasting device which utilizes the instantaneous rise of the phase-change gasification pressure of liquid carbon dioxide in a limited space to break a constant-pressure shear slice to form high-pressure high-energy gas so as to achieve the directional blasting effect. The blasting is a physical conversion process, and open fire and electric arc are not generated in the blasting process; and the blasting power is high, the blasting inspection is not needed, the operation is simple, and the like, and the method is widely applied to various domestic industries.

However, due to structural limitations, the conventional carbon dioxide fracturing device needs to be filled with liquid carbon dioxide outside the hole and then sent into the drill hole; during the period from the completion of filling to the feeding of the fracturing device into the drill hole, the fracturing device is always in a pressurized state, sometimes, due to the change of the external environment temperature, the internal pressure of the fracturing device is increased, air leakage and other phenomena occur, meanwhile, the self-explosion phenomenon of the fracturing device also occurs, the injury accident is caused, and the potential safety hazard exists.

Disclosure of Invention

In view of the above, embodiments of the present invention provide a disposable hole filled with a carbon dioxide cracking device and a method for installing the carbon dioxide cracking device in a drill hole, which can at least solve the above technical problems and facilitate improvement of safety of the carbon dioxide cracking device during use.

In a first aspect, an embodiment of the present invention provides a disposable downhole carbon dioxide cracking device, including: the heating device comprises a tube body, a heating rod, a filling head, a one-way air inlet valve and an external air pipe, wherein one end of the tube body is a closed end, the other end of the tube body is an open end, an energy discharge port is formed in the tube body, and the filling head is connected to the open end of the tube body and seals the open end of the tube body;

fill and be equipped with the excellent installation department that generates heat on the head, the stick that generates heat includes: the base is installed in a heating rod installation part on the filling head, the paper tube is arranged in the tube body, the outer end of the paper tube is connected to the inner end of the base, the wiring terminal axially penetrates through the base, the first end of the wiring terminal extends out of the outer end of the base, the second end of the wiring terminal extends out of the inner end of the base and is arranged in the paper tube, the electric ignition head is connected to the second end of the wiring terminal, and heating agents are filled in the paper tube;

the filling head is also provided with a filling channel for filling carbon dioxide into the main pipe, the filling channel is internally provided with a one-way air inlet valve for opening and closing the filling channel, the one-way air inlet valve is provided with an air inlet and an air outlet, the external air pipe is connected to the air inlet of the one-way air inlet valve, and the air outlet is communicated with the inside of the pipe body.

Optionally, the filling channel includes a first-stage duct and a second-stage duct, a diameter of the first-stage duct is larger than that of the second-stage duct, an inner contour of the first-stage duct is identical to an outer contour of a valve body of the one-way air intake valve, the one-way air intake valve is installed in the first-stage duct, a first end of the second-stage duct is in butt joint with an air outlet of the one-way air intake valve, and a second end of the second-stage duct is communicated with the inside of the pipe body.

Optionally, the energy release port is a slit axially arranged along the outer wall of the pipe body.

Optionally, the slit is a linear elongated slit groove.

Optionally, the axial midpoint position of the slit coincides with the midpoint position of the pipe body.

Optionally, the length of the slit is 1/3 of the length of the pipe body, the width of the slit is 3-5 mm, and the depth of the slit is 1/5 of the wall thickness of the pipe body.

Optionally, the filling head is welded to the open end of the tube body.

Optionally, the terminal comprises two terminals which are parallelly arranged on the charging head in a penetrating manner, the second ends of the two terminals are respectively connected with a conducting wire, and the tail ends of the two conducting wires are respectively connected with the electric ignition head.

In a second aspect, the present invention provides a method for installing a carbon dioxide cracker in a borehole, the method being implemented based on filling a disposable hole with the carbon dioxide cracker according to any one of the first aspect, the method comprising the steps of:

feeding the carbon dioxide fracker into a borehole; wherein the pipe body of the carbon dioxide cracking device is not filled with liquid carbon dioxide;

after the carbon dioxide cracking device is fed into the drill hole, connecting an external air pipe to an air outlet of carbon dioxide filling equipment, starting the carbon dioxide filling equipment, and filling liquid carbon dioxide into the external air pipe;

when the amount of liquid carbon dioxide flowing from the external air pipe to the air inlet of the one-way air inlet valve is increased to a preset amount, the channel of the one-way air inlet valve is automatically opened, and the liquid carbon dioxide enters the pipe body of the carbon dioxide cracking device until the inside of the carbon dioxide cracking device is filled to a preset pressure value.

According to the disposable hole-filling carbon dioxide cracking device and the method for installing the same into the drill hole, provided by the embodiment of the invention, the one-way air inlet valve is installed in the filling channel of the filling head, the external air pipe is arranged on the air inlet of the one-way air inlet valve, and when the cracking device is installed into the drill hole, liquid carbon dioxide can be filled into the pipe body of the cracking device through the external air pipe when the cracking device is installed into the drill hole, so that the potential safety hazard of the traditional carbon dioxide cracking device caused by the fact that the liquid carbon dioxide is filled outside the hole due to the structural limitation is solved, and the safety of the carbon dioxide cracking device in use is improved conveniently.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a cross-sectional view of a disposable downhole carbon dioxide fracturing device in accordance with an embodiment of the present invention;

fig. 2 is a schematic structural diagram of a disposable hole filled with a carbon dioxide cracking device according to another embodiment of the invention.

Detailed Description

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

It should be apparent that numerous technical details are set forth in the following specific examples in order to provide a more thorough description of the present invention, and it should be apparent to one skilled in the art that the present invention may be practiced without some of these details. In addition, some methods, means, components and applications thereof known to those skilled in the art are not described in detail in order to highlight the gist of the present invention, but the implementation of the present invention is not affected thereby. The embodiments described herein are only a few embodiments of the present invention, and not all embodiments. 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.

The disposable downhole carbon dioxide filling fracturing device provided by the embodiment of the invention is simple in structure, is suitable for rock blasting in mine engineering, is especially suitable for directional presplitting blasting occasions with the requirement of controlling rock blasting forming, and is high in safety and good in blasting effect.

Referring to fig. 1 and 2, the disposable downhole carbon dioxide filled fracturing device comprises: the heating tube comprises a tube body 1, a heating rod, a filling head 2, a one-way air inlet valve 3 and an external air tube 4, wherein one end of the tube body 1 is a closed end, the other end of the tube body 1 is an open end, an energy release port 5 is arranged on the tube body 1, and the filling head 2 is connected to the open end of the tube body 1 and seals the open end of the tube body 1;

be equipped with the excellent installation department that generates heat on filling head 2, the stick that generates heat includes: the electric heating tube comprises a base 6, a wiring terminal 7, a paper tube 8 and an electric ignition head 9, wherein the base 6 is installed in a heating rod installation part on the filling head 2, the paper tube 8 is arranged in the tube body 1, the outer end of the paper tube 8 is connected to the inner end of the base 6, the wiring terminal 7 axially penetrates through the base 6, the first end of the wiring terminal 7 extends out of the outer end of the base 6, the second end of the wiring terminal 7 extends out of the inner end of the base 6 and is arranged in the paper tube 8, the electric ignition head 9 is connected to the second end of the wiring terminal 7, and heating agents are filled in the paper tube 8;

still be equipped with on the filling head 2 and be used for filling the dress passageway of filling carbon dioxide to being responsible for inside being equipped with the one-way admission valve 3 that opens and close the dress passageway in filling the dress passageway, one-way admission valve 3 has air inlet and gas outlet, external trachea 4 connect in on the air inlet of one-way valve, the gas outlet with the inside UNICOM of body 1.

Wherein, the pipe body 1 is processed by adopting an one-step forming plate rolling process so as to ensure the strength. The material of the pipe body 1 is Q235 steel. In addition, in the implementation, the pipe body 1 is manufactured by adopting the one-step forming plate rolling processing technology, so that the processing technology of the cracking device is changed, the processing efficiency is improved, and the manufacturing cost is reduced.

The one-way air inlet valve 3 comprises a valve body, the valve body is an annular shell with an inner cavity and two open ends, the inner cavity of the valve body is divided into a first cavity section, a second cavity section and a third cavity section from outside to inside in sequence, a connecting part is arranged on the inner wall of the first cavity section and can be used for connecting an external pipeline, and the second cavity section is of a stepped structure and comprises two stepped sections; the diameter of the step section adjacent to the first cavity section is larger than that of the first cavity section, the diameter of the step section far away from the first cavity section is smaller than that of the first cavity section, a valve core and a spring abutted to one side of the valve core are arranged in the step section far away from the first cavity section, the other end of the spring is fixed in the step section far away from the first cavity section, when liquid carbon dioxide entering from a gas inlet on the left side of the one-way gas inlet valve 3 reaches the opening pressure of the valve core, the valve core is automatically opened, and the liquid carbon dioxide flows out from a gas outlet of the one-way gas inlet valve 3.

According to the disposable hole-filled carbon dioxide cracking device provided by the embodiment of the invention, the one-way air inlet valve 3 is arranged in the filling channel of the filling head 2, the external air pipe 4 is arranged on the air inlet of the one-way air inlet valve 3, and when the cracking device is arranged in a drill hole, liquid carbon dioxide can be filled into the pipe body 1 of the cracking device through the external air pipe 4 when the cracking device is arranged in the drill hole, so that the potential safety hazard of the traditional carbon dioxide cracking device caused by the fact that the liquid carbon dioxide is filled outside the hole due to the structural limitation is solved, and the safety of the carbon dioxide cracking device in use is improved conveniently.

In some embodiments, the filling head 2 is welded to the open end of the tubular body 1. Specifically, the filling head 2 and the pipe body 1 can be welded by a full-automatic welding machine, so that the welding uniformity is ensured, and the quality of a welding seam is ensured.

The external air pipe 4 is made of a seamless steel pipe. The seamless steel pipe has a hollow cross section, and is lighter in weight when the bending strength and the torsional strength are the same as those of a solid steel material.

The filling channel comprises a first-stage pore channel and a second-stage pore channel, the diameter of the first-stage pore channel is larger than that of the second-stage pore channel, the inner contour of the first-stage pore channel is consistent with the outer contour of a valve body of the one-way air inlet valve 3, the one-way air inlet valve 3 is installed in the first-stage pore channel, the first end of the second-stage pore channel is in butt joint with an air outlet of the one-way air inlet valve 3, and the second end of the second-stage pore channel is communicated with the inside of the pipe body 1.

In the embodiment, the first-stage pore passage is larger than the second-stage pore passage, so that the requirement of installing the one-way air valve is met; set up like this for fill the air inlet end of passageway be greater than with the air outlet end of the inside UNICOM of body 1, can guarantee to fill the stability of liquid carbon dioxide.

With reference to fig. 1, the paper tube 8 is disposed in the tube body 1, and a cavity is formed between the outer wall of the paper tube 8 and the inner wall of the tube body 1, and the liquid carbon dioxide enters the tube body 1 and then fills the cavity.

The excellent installation department that generates heat for with fill the mounting hole that the passageway parallel set up, the base 6 of the stick that generates heat closes soon fill in the mounting hole of dress head 2, just the outer end of base 6 press against on the outer terminal surface of dress head 2.

With continued reference to fig. 1, in some embodiments, the terminals 7 include two terminals passing through the charging head 2 in parallel, and serving as positive and negative electrodes, respectively, and the second ends of the two terminals 7 are connected with conducting wires, respectively, and the ends of the two conducting wires are connected with the electric ignition head 9, respectively.

Referring to fig. 2, the heating rod is a component for providing heat energy for gasifying the liquid carbon dioxide, and by connecting the first end of the binding post 7 to the exploder 10, under the excitation of the electric ignition head 9, the heating agent is ignited and burns in the paper tube 8, so as to gasify the liquid carbon dioxide, and when the air pressure in the tube body 1 reaches a certain value, the liquid carbon dioxide is directionally sprayed from the energy discharge port 5, so as to realize directional fracture explosion.

Specifically, a hole is reserved on the base 6, and the wiring terminal 7 is arranged in the hole in a penetrating manner. In some embodiments, a gasket is further disposed between the inner side surface of the first end of the base 6 and the outer end surface of the filling head 2.

It can be understood that, generally, the carbon dioxide fracturing device releases high-energy high-pressure gas from the energy release end, and the long-diameter ratio of the carbon dioxide fracturing device is large, so that the carbon dioxide fracturing device can be approximately regarded as point blasting, and the energy release end of the fracturing device is generally provided with a plurality of air vents, so that the carbon dioxide fracturing device installed in a drill hole cannot control the direction of the air vents, and cannot form the directional blasting effect; therefore, most blasting has the phenomena of overbreak, underexcavation, uneven periphery and serious slope damage due to the limitation of the self structure.

Therefore, in order to solve the above technical problem, with continued reference to fig. 1, in some embodiments, the energy discharge opening 5 is a slit axially disposed along the outer wall of the pipe body 1. The joint cutting position should be kept away from the joint position of the pipe body 1 when being arranged so as to ensure the integral strength of the pipe body 1. Specifically, the midpoint position of the slit along the axial direction coincides with the midpoint position of the pipe body 1.

Preferably, the slits are linear elongated slits. Therefore, the long-strip-shaped slit cutting groove is reserved on the outer side of the pipe body 1, the guide cracking device is led to break preferentially from the direction of the slit cutting groove, high-energy high-pressure airflow is promoted to cut directionally, and the directional blasting effect is achieved.

In some embodiments, the length of the slit is 1/3 of the length of the pipe body 1, the width of the slit is 3-5 mm, and the depth of the slit is 1/5 of the wall thickness of the pipe body 1.

In one embodiment, for example, blasting is performed with the carbon dioxide cracker; when the carbon dioxide cracking device is installed in the drill hole, a cutting seam of the carbon dioxide cracking device faces to one side of the directional blasting; when a plurality of drill holes are blasted simultaneously, one side of the fracturing device with the slit grooves faces the same direction, high-energy high-pressure gas flows are released in the same direction, and under the combined action of stress waves formed by blasting and a blasting gas static wedge, rocks between the drill holes are directionally fractured along the preset direction, so that a precisely controlled blasting fracture surface is obtained, the number of cracks in other directions such as surrounding rocks and side slopes is reduced, the crack expansion length in the direction needing to be protected is limited, and the blasting effect is improved; meanwhile, the later-stage treatment cost of the surrounding rock and the side slope is reduced. The technical scheme of the invention is particularly suitable for directional fracture control blasting of rock tunnels, tunnels and side slopes.

According to the disposable hole-filled carbon dioxide fracturing device provided by the embodiment of the invention, the structure of the fracturing device is improved, so that the current filling process of the carbon dioxide fracturing device is changed, and the filling in a drill hole is safer; furthermore, the carbon dioxide cracking device is disposable, so that the recovery link is avoided, and the construction efficiency is improved to a certain extent; furthermore, by arranging the unilateral slotted groove, the current energy leakage end point-shaped energy leakage mode is changed, the directional fracture blasting control effect can be formed, and further the unnecessary damage to the surrounding rock is reduced, so that the blasting effect is improved.

Based on the disposable hole filled with the carbon dioxide cracking device provided by the embodiment, the method for installing the carbon dioxide cracking device into the drill hole is also provided, and comprises the following steps:

s1, conveying the carbon dioxide fracturing device into a drill hole; wherein, the pipe body 1 of the carbon dioxide cracking device is not filled with liquid carbon dioxide.

In the embodiment, in the process of pushing the carbon dioxide fracturing device into the drill hole, the supporting rod is connected to the fracturing device at the drill hole opening, and the carbon dioxide fracturing device is propped against the supporting rod so as to ensure that the carbon dioxide fracturing device does not slip out of the drill hole.

And S2, after the carbon dioxide cracking device is conveyed into the drill hole, connecting the external air pipe 4 to an air outlet of carbon dioxide filling equipment, starting the carbon dioxide filling equipment, and filling liquid carbon dioxide into the external air pipe 4.

S3, when the amount of the liquid carbon dioxide flowing from the external air pipe 4 to the air inlet of the one-way air inlet valve 3 increases to a preset amount, the channel of the one-way air inlet valve 3 is automatically opened, and the liquid carbon dioxide enters the inside of the pipe body 1 of the carbon dioxide cracking device until the inside of the carbon dioxide cracking device is filled to a preset pressure value.

The one-way air inlet valve 3 is a part for controlling liquid carbon dioxide to enter the fracturing device, when the liquid carbon dioxide is filled into the fracturing device from the outside, the one-way air inlet valve 3 is automatically opened, and liquid enters the fracturing device; in some embodiments, when the filling pressure inside the fracturing device reaches 10MPa, the one-way air inlet valve 3 automatically closes to stop filling.

The embodiment of the invention changes the current filling process of the carbon dioxide cracking device, and the carbon dioxide cracking device is safer to fill after being arranged in the drill hole; furthermore, the carbon dioxide cracking device is disposable, so that the recovery process is avoided, and the construction efficiency can be improved to a certain extent.

In order to facilitate the subsequent blasting process, the first end of the binding post 7 can be connected to the mining explosion-proof type exploder 10, so that the carbon dioxide exploder is detonated through the exploder 10.

After the carbon dioxide cracker is installed in the drilled hole, the method further comprises a step S4 of detonating the electric igniter 9 in the paper tube 8 by the exploder 10, and instantly gasifying the liquid carbon dioxide in the tube body 1 by the heat energy released by the electric igniter 9, and increasing the pressure in the tube.

And S5, when the pressure reaches the shear strength limit of the slit groove arranged on the side wall of the pipe body 1, the slit groove is sheared and damaged, the high-energy and high-pressure carbon dioxide gas is released along the slit groove to form linear cutting airflow, and the coal rock mass is cut in the preset direction to realize directional fracture blasting.

It can be understood that the shear strength of the slit is lower than that of the rest positions of the side wall of the main pipe, when the pressure in the pipe body 1 reaches the shear strength limit of the slit, the slit is destroyed, and the airflow impacts outwards along the slit from the destroyed slit to form linear cutting airflow acting on the rock mass.

In the embodiment of the invention, the linear energy leakage of the single-side cutting kerve is adopted, and the current energy leakage end point-shaped energy leakage mode is changed, so that the effect of controlling blasting by directional fracture can be formed, further the unnecessary damage to surrounding rocks is reduced, and the blasting effect is improved.

It should be noted that, in this document, the emphasis points of the solutions described in the embodiments are different, but there is a certain correlation between the embodiments, and in understanding the solution of the present invention, the embodiments may be referred to each other; moreover, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.