阅读说明：本技术 一种液压插销升降系统 (Hydraulic bolt lifting system ) 是由 张磊 宫小康 刘聪 于 2019-10-10 设计创作，主要内容包括：本发明公开了一种液压插销升降系统,其包括第一升降油缸、第一插销油缸、第一液压装置、第二升降油缸、第二插销油缸和第二液压装置；所述第一液压装置通过第一油路与所述第一升降油缸连通,所述第一液压装置通过第二油路与所述第一插销油缸连通；所述第二液压装置通过第三油路与所述第二升降油缸连通,所述第二液压装置通过第四油路与所述第二插销油缸连通；所述第一油路通过第一备用油路与所述第三油路连通；所述第二油路通过第二备用油路与所述第四油路连通。本发明所述的液压插销升降系统,其能够持续为桩腿提供升降动力,保证升降作业的持续进行,有效提高工作效率。(The invention discloses a hydraulic bolt lifting system which comprises a first lifting oil cylinder, a first bolt oil cylinder, a first hydraulic device, a second lifting oil cylinder, a second bolt oil cylinder and a second hydraulic device, wherein the first lifting oil cylinder is connected with the first bolt oil cylinder; the first hydraulic device is communicated with the first lifting oil cylinder through a first oil way, and the first hydraulic device is communicated with the first bolt oil cylinder through a second oil way; the second hydraulic device is communicated with the second lifting oil cylinder through a third oil way, and the second hydraulic device is communicated with the second bolt oil cylinder through a fourth oil way; the first oil path is communicated with the third oil path through a first standby oil path; the second oil passage is communicated with the fourth oil passage through a second spare oil passage. The hydraulic bolt lifting system can continuously provide lifting power for the pile leg, ensures continuous lifting operation, and effectively improves the working efficiency.)

1. A hydraulic bolt lifting system is characterized by comprising

The hydraulic lifting device comprises a first lifting oil cylinder, a first bolt oil cylinder, a first hydraulic device, a second lifting oil cylinder, a second bolt oil cylinder and a second hydraulic device;

the first hydraulic device is communicated with the first lifting oil cylinder through a first oil way, and the first hydraulic device is communicated with the first bolt oil cylinder through a second oil way;

the second hydraulic device is communicated with the second lifting oil cylinder through a third oil way, and the second hydraulic device is communicated with the second bolt oil cylinder through a fourth oil way;

the first oil path is communicated with the third oil path through a first standby oil path;

the second oil passage is communicated with the fourth oil passage through a second spare oil passage.

2. The hydraulic latch lifting system according to claim 1, wherein a first ball valve is provided on the first oil path, a second ball valve is provided on the second oil path, a third ball valve is provided on the third oil path, and a fourth ball valve is provided on the fourth oil path; and a first standby ball valve is arranged on the first standby oil way, and a second standby ball valve is arranged on the second standby oil way.

3. The hydraulic latch lift system according to claim 1, wherein said first hydraulic means includes a first main pump mechanism and a first auxiliary pump mechanism, said first main pump mechanism communicating with said first lift cylinder through said first oil passage, said first auxiliary pump mechanism communicating with said first latch cylinder through said second oil passage.

4. The hydraulic latch lifting system according to claim 1, wherein said second hydraulic means comprises a second main pump mechanism and a second auxiliary pump mechanism, said second main pump mechanism communicating with said second lift cylinder through said third oil passage, said second auxiliary pump mechanism communicating with said second latch cylinder through said fourth oil passage.

5. The hydraulic latch lift system of claim 2 wherein said first oil passage communicates with said first backup oil passage at a first connection point; the second oil passage is communicated with the second spare oil passage at a second connecting point; the third oil passage is communicated with the first spare oil passage at a third connecting point; the fourth oil passage communicates with the second backup oil passage at a fourth connection point.

6. The hydraulic latch lift system according to claim 5, wherein a first three-way valve is provided at said first connection point; a second three-way valve is arranged at the second connecting point; a third three-way valve is arranged at the third connecting point; and a fourth three-way valve is arranged at the fourth connecting point.

7. The hydraulic latch lift system according to claim 6, wherein said first ball valve is located between said first three way valve and said first lift cylinder; the second ball valve is positioned between the second three-way valve and the first bolt oil cylinder; the third ball valve is positioned between the third three-way valve and the second lifting oil cylinder; and the fourth ball valve is positioned between the fourth three-way valve and the second bolt oil cylinder.

8. The hydraulic latch lifting system according to any of claims 1-7, wherein said first hydraulic means further comprises a first oil return tank, and said second hydraulic means further comprises a second oil return tank; the first lifting oil cylinder is communicated with the first oil return tank through a first oil return path, and the second lifting oil cylinder is communicated with the second oil return tank through a second oil return path;

the first oil return path and the second oil return path are communicated through a standby oil return path.

9. The hydraulic latch lift system according to claim 8, wherein said first oil return is in communication with said backup oil return at a fifth connection point; the second oil return path is communicated with the standby oil return path at a sixth connecting point;

and a fifth ball valve is arranged on the first oil return path, a sixth ball valve is arranged on the second oil return path, and a third standby ball valve is arranged on the standby oil return path.

10. The hydraulic latch lift system according to claim 9, wherein said fifth ball valve is positioned between said fifth junction and said first oil return tank, and said sixth ball valve is positioned between said sixth junction and said second oil return tank.

Technical Field

The invention relates to the technical field of self-elevating platforms, in particular to a hydraulic bolt lifting system.

Background

The lifting platform is a large ship machine and is divided into a rack and pinion type lifting platform and a bolt type lifting platform according to different lifting modes. At present, more than 80% of lifting systems of domestic wind power installation ships are hydraulic bolt type, common bolt type lifting platforms mainly comprise pile legs, platforms and hydraulic bolt lifting systems, and the hydraulic bolt lifting systems comprise oil cylinders for driving the platforms to lift and hydraulic devices for providing power for the oil cylinders. The platform is supported by at least two pile legs, usually, one pile leg is correspondingly provided with a set of hydraulic device, the hydraulic device provides power for the lifting of the corresponding pile leg, and when the hydraulic device corresponding to one pile leg breaks down, the corresponding pile leg loses power, so that the lifting operation is stopped.

Disclosure of Invention

In view of the above problems, an object of the present invention is to provide a hydraulic latch lifting system to solve the technical problem in the prior art that when a hydraulic device corresponding to a leg fails, the leg loses power, so that the lifting operation is stopped.

In order to achieve the above object, the present invention provides a hydraulic latch lifting system, which includes a first lifting cylinder, a first latch cylinder, a first hydraulic device, a second lifting cylinder, a second latch cylinder, and a second hydraulic device;

the first hydraulic device is communicated with the first lifting oil cylinder through a first oil way, and the first hydraulic device is communicated with the first bolt oil cylinder through a second oil way;

the second hydraulic device is communicated with the second lifting oil cylinder through a third oil way, and the second hydraulic device is communicated with the second bolt oil cylinder through a fourth oil way;

the first oil path is communicated with the third oil path through a first standby oil path;

the second oil passage is communicated with the fourth oil passage through a second spare oil passage.

Further, a first ball valve is arranged on the first oil path, a second ball valve is arranged on the second oil path, a third ball valve is arranged on the third oil path, and a fourth ball valve is arranged on the fourth oil path; and a first standby ball valve is arranged on the first standby oil way, and a second standby ball valve is arranged on the second standby oil way.

Further, the first hydraulic device comprises a first main pump mechanism and a first auxiliary pump mechanism, the first main pump mechanism is communicated with the first lifting oil cylinder through the first oil path, and the first auxiliary pump mechanism is communicated with the first bolt oil cylinder through the second oil path.

Further, the second hydraulic device comprises a second main pump mechanism and a second auxiliary pump mechanism, the second main pump mechanism is communicated with the second lifting oil cylinder through the third oil path, and the second auxiliary pump mechanism is communicated with the second bolt oil cylinder through the fourth oil path.

Further, the first oil passage communicates with the first backup oil passage at a first connection point; the second oil passage is communicated with the second spare oil passage at a second connecting point; the third oil passage is communicated with the first spare oil passage at a third connecting point; the fourth oil passage communicates with the second backup oil passage at a fourth connection point.

Further, a first three-way valve is arranged at the first connecting point; a second three-way valve is arranged at the second connecting point; a third three-way valve is arranged at the third connecting point; and a fourth three-way valve is arranged at the fourth connecting point.

Further, the first ball valve is positioned between the first three-way valve and the first lifting oil cylinder; the second ball valve is positioned between the second three-way valve and the first bolt oil cylinder; the third ball valve is positioned between the third three-way valve and the second lifting oil cylinder; and the fourth ball valve is positioned between the fourth three-way valve and the second bolt oil cylinder.

Further, the first hydraulic device further comprises a first oil return tank, and the second hydraulic device further comprises a second oil return tank; the first lifting oil cylinder is communicated with the first oil return tank through a first oil return path, and the second lifting oil cylinder is communicated with the second oil return tank through a second oil return path;

the first oil return path and the second oil return path are communicated through a standby oil return path.

Further, the first oil return path is communicated with the standby oil return path at a fifth connecting point; the second oil return path is communicated with the standby oil return path at a sixth connecting point;

and a fifth ball valve is arranged on the first oil return path, a sixth ball valve is arranged on the second oil return path, and a third standby ball valve is arranged on the standby oil return path.

Further, the fifth ball valve is located between the fifth connecting point and the first oil return tank, and the sixth ball valve is located between the sixth connecting point and the second oil return tank.

Compared with the prior art, the hydraulic bolt lifting system provided by the invention has the following technical effects:

the first hydraulic device is designed to be communicated with the first lifting oil cylinder through a first oil way, and the first hydraulic device is designed to be communicated with the first bolt oil cylinder through a second oil way; the second hydraulic device is communicated with the second lifting oil cylinder through a third oil way, and the second hydraulic device is communicated with the second bolt oil cylinder through a fourth oil way; the first oil path is communicated with the third oil path through a first standby oil path; the second oil path is communicated with the fourth oil path through a second standby oil path; therefore, when the first hydraulic device or the second hydraulic device breaks down, the second hydraulic device or the first hydraulic device can simultaneously provide power for the first lifting oil cylinder, the second lifting oil cylinder, the first bolt oil cylinder and the second bolt oil cylinder, so that the lifting power is continuously provided for the pile leg, the continuous operation of the lifting operation is ensured, and the working efficiency is effectively improved.

Drawings

FIG. 1 is a schematic structural view of a hydraulic latch lifting system of the present invention under normal operating conditions;

fig. 2 is a schematic structural view of the hydraulic latch lifting system of the present invention under an emergency condition.

10, a hydraulic bolt lifting system, 110, a first lifting oil cylinder, 120, a first bolt oil cylinder, 130, a first hydraulic device, 210, a second lifting oil cylinder, 220, a second bolt oil cylinder, 230, a second hydraulic device, 31, a first oil path, 32, a second oil path, 33, a third oil path, 34, a fourth oil path, 35, a first spare oil path, 36, a second spare oil path, 37, a first oil return path, 38, a second oil return path, 39, a spare oil return path, 41, a first ball valve, 42, a second ball valve, 43, a third ball valve, 44, a fourth ball valve, 45, a first spare ball valve, 46, a second spare ball valve, 47, a fifth ball valve, 48, a sixth ball valve, 49, a third spare ball valve, 51, a first three-way valve, 52, a second three-way valve, 53, a third three-way valve, 54, a fourth three-way valve, 61, a fifth connection point, 62, and a sixth connection point.

Detailed Description

In the description of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the referred device or element 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 technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the 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.

As shown in fig. 1 and 2, a hydraulic latch lifting system 10 according to an embodiment of the present invention includes a first lifting cylinder 110, a first latch cylinder 120, a first hydraulic device 130, a second lifting cylinder 210, a second latch cylinder 220, and a second hydraulic device 230; the first hydraulic device 130 is communicated with the first lift cylinder 110 through a first oil path 31, and the first hydraulic device 130 is communicated with the first latch oil cylinder 120 through a second oil path 32; the second hydraulic device 230 is communicated with the second lift cylinder 210 through a third oil path 33, and the second hydraulic device 230 is communicated with the second latch cylinder 220 through a fourth oil path 34; the first oil passage 31 communicates with the third oil passage 33 through a first backup oil passage 35; the second oil passage 32 communicates with the fourth oil passage 34 through a second backup oil passage 36;

by designing the first hydraulic device 130 to be communicated with the first lift cylinder 110 through a first oil path 31, the first hydraulic device 130 is communicated with the first latch oil cylinder 120 through a second oil path 32; the second hydraulic device 230 is communicated with the second lift cylinder 210 through a third oil path 33, and the second hydraulic device 230 is communicated with the second latch cylinder 220 through a fourth oil path 34; the first oil passage 31 communicates with the third oil passage 33 through a first backup oil passage 35; the second oil passage 32 communicates with the fourth oil passage 34 through a second backup oil passage 36; therefore, when the first hydraulic device 130 or the second hydraulic device 230 fails, the second hydraulic device 230 or the first hydraulic device 130 can provide power for the first lifting cylinder 110, the second lifting cylinder 210, the first bolt cylinder 120 and the second bolt cylinder 220 at the same time, so that the lifting power is continuously provided for the pile leg, the continuous lifting operation is ensured, and the working efficiency is effectively improved.

Specifically, in the embodiment of the present invention, the hydraulic pin lifting system 10 includes an upper ring beam, a lower ring beam, a lifting cylinder, an upper pin, a lower pin, and a pin cylinder, each of the legs is provided with the upper ring beam and the lower ring beam, and the platform is fixed on the leg through the upper ring beam pin and the lower ring beam pin. The upper ring beam and the lower ring beam on the pile leg are synchronously lifted and lowered by the lifting oil cylinder so as to drive the platform to lift.

Further, referring to fig. 1 and fig. 2, a first ball valve 41 is disposed on the first oil path 31, a second ball valve 42 is disposed on the second oil path 32, a third ball valve 43 is disposed on the third oil path 33, and a fourth ball valve 44 is disposed on the fourth oil path 34; the first standby oil path 35 is provided with a first standby ball valve 45, and the second standby oil path 36 is provided with a second standby ball valve 46. Thus, the first hydraulic device 130 can be communicated with the first lift cylinder 110, the first latch cylinder 120, the second lift cylinder 210 and the second latch cylinder 220 by controlling the opening or closing of the first ball valve 41, the second ball valve 42, the third ball valve 43, the fourth ball valve 44, the first standby ball valve 45 and the second standby ball valve 46; the second hydraulic device 230 is communicated with the first lift cylinder 110, the first latch cylinder 120, the second lift cylinder 210 and the second latch cylinder 220.

Specifically, in the embodiment of the present invention, the normal operating conditions are: the first ball valve 41, the second ball valve 42, the third ball valve 43 and the fourth ball valve 44 are all opened, and the first standby ball valve 45 and the second standby ball valve 46 are all closed; that is, the first hydraulic device 130 is communicated with the first lift cylinder 110 and the first latch cylinder 120 to provide power for the first lift cylinder 110 and the first latch cylinder 120, and the second hydraulic device 230 is communicated with the second lift cylinder 210 and the second latch cylinder 220 to provide power for the second lift cylinder 210 and the second latch cylinder 220.

The emergency working condition is as follows: when the first hydraulic device 130 fails and cannot work, the first ball valve 41, the second ball valve 42, the third ball valve 43, the fourth ball valve 44, the first standby ball valve 45 and the second standby ball valve 46 are all opened; that is, the second hydraulic device 230 is communicated with the first lift cylinder 110, the first latch cylinder 120, the second lift cylinder 210, and the second latch cylinder 220 to provide power for the first lift cylinder 110, the first latch cylinder 120, the second lift cylinder 210, and the second latch cylinder 220.

Further, referring to fig. 1 and 2, the first hydraulic device 130 includes a first main pump mechanism and a first auxiliary pump mechanism, the first main pump mechanism is communicated with the first lift cylinder 110 through the first oil path 31, and the first auxiliary pump mechanism is communicated with the first latch cylinder 120 through the second oil path 32.

Further, referring to fig. 1 and 2, the second hydraulic device 230 includes a second main pump mechanism and a second auxiliary pump mechanism, the second main pump mechanism is communicated with the second lift cylinder 210 through the third oil path 33, and the second auxiliary pump mechanism is communicated with the second latch cylinder 220 through the fourth oil path 34.

Optionally, in an embodiment, the first main pump system includes two first main pumps and two first vane pumps, the two first main pumps and the two first vane pumps are respectively communicated with the first lift cylinder 110 through one first oil path 31, the four first oil paths 31 are respectively communicated with the third oil path 33 through one first backup oil path 35, the first ball valve 41 is disposed on each of the four first oil paths 31, and the first backup ball valve 45 is disposed on each of the four first backup oil paths 35;

the first auxiliary pump system comprises two first auxiliary pumps, the two first auxiliary pumps are respectively communicated with the first bolt oil cylinder 120 through one second oil path 32, the two second oil paths 32 are respectively communicated with the fourth oil path 34 through one second standby oil path 36, the second ball valve 42 is arranged on each second oil path 32, and the second standby ball valve 46 is arranged on each second standby oil path 36.

The second main pump system comprises two second main pumps and two second vane pumps, the two second main pumps and the two second vane pumps are respectively communicated with the second lift cylinder 210 through one third oil path 33, and the four third oil paths 33 are respectively provided with the third ball valves 43;

the second auxiliary pump system comprises two second auxiliary pumps, the two second auxiliary pumps are respectively communicated with the second bolt oil cylinder 220 through one fourth oil path 34, and the fourth ball valves 44 are arranged on the two fourth oil paths 34.

Further, referring to fig. 1 and 2, the first oil path 31 communicates with the first backup oil path 35 at a first connection point; the second oil passage 32 communicates with the second backup oil passage 36 at a second connection point; the third oil passage 33 communicates with the first backup oil passage 35 at a third connecting point; the fourth oil passage 34 communicates with the second backup oil passage 36 at a fourth connection point.

Further, referring to fig. 1 and fig. 2, a first three-way valve 51 is disposed at the first connection point; a second three-way valve 52 is arranged at the second connecting point; a third three-way valve 53 is arranged at the third connecting point; a fourth three-way valve 54 is provided at the fourth connection point.

Further, referring to fig. 1 and 2, the first ball valve 41 is located between the first three-way valve 51 and the first lift cylinder 110; the second ball valve 42 is located between the second three-way valve 52 and the first latch cylinder 120; the third ball valve 43 is located between the third three-way valve 53 and the second lift cylinder 210; the fourth ball valve 44 is located between the fourth three-way valve 54 and the second latch cylinder 220.

Further, referring to fig. 1 and fig. 2, the first hydraulic device 130 further includes a first oil return tank, and the second hydraulic device 230 further includes a second oil return tank; the first lift cylinder 110 is communicated with the first oil return tank through a first oil return path 37, and the second lift cylinder 210 is communicated with the second oil return tank through a second oil return path 38;

the first oil return passage 37 and the second oil return passage 38 communicate through a backup oil return passage 39.

Further, referring to fig. 1 and 2, the first oil return path 37 communicates with the spare oil return path 39 at a fifth connection point 61; the second oil return 38 communicates with the backup oil return 39 at a sixth connection point 62;

a fifth ball valve 47 is arranged on the first oil return path 37, a sixth ball valve 48 is arranged on the second oil return path 38, and a third standby ball valve 49 is arranged on the standby oil return path 39.

Further, referring to fig. 1 and 2, the fifth ball valve 47 is located between the fifth connection point 61 and the first oil return tank, and the sixth ball valve 48 is located between the sixth connection point 62 and the second oil return tank.

Specifically, in one embodiment, the normal operating conditions are: the first ball valve 41, the second ball valve 42, the third ball valve 43, the fourth ball valve 44, the fifth ball valve 47 and the sixth ball valve 48 are all opened, and the first standby ball valve 45, the second standby ball valve 46 and the third standby ball valve 49 are all closed; namely, the first main pump system is communicated with the first lift cylinder 110 through the first oil path 31 to provide lifting power for the first lift cylinder 110, the first auxiliary pump system is communicated with the first latch cylinder 120 through the second oil path 32 to provide plugging power for the first latch cylinder 120, and the first lift cylinder 110 and the first latch cylinder 120 return oil to the first oil return tank; the second main pump system is communicated with the second lifting oil cylinder 210 through the third oil path 33 to provide lifting power for the second lifting oil cylinder 210, the second auxiliary pump system is communicated with the second bolt oil cylinder 220 through the fourth oil path 34 to provide plugging power for the second bolt oil cylinder 220, and the second lifting oil cylinder 210 and the second bolt oil cylinder 220 return oil to the second oil return tank.

The emergency working condition is as follows: when the first hydraulic device 130 fails and cannot work, the first ball valves 41 on two first oil paths 31 of the four first oil paths 31 are opened, the first standby ball valves 45 on two corresponding first standby oil paths 35 are also opened, meanwhile, the first ball valves 41 on the other two first oil paths 31 are closed, and the first standby ball valves 45 on two corresponding first standby oil paths 35 are also closed; the second ball valve 42 on one of the two second oil passages 32 is opened, the second spare ball valve 46 on the corresponding second spare oil passage 36 is also opened, meanwhile, the second ball valve 42 on the other second oil passage 32 is closed, and the second spare ball valve 46 on the corresponding second spare oil passage 36 is also closed; the fifth ball valve 47 is closed, and the sixth ball valve 48 and the third standby ball valve 49 are opened;

the third ball valves 43 on three of the four third oil passages 33 are opened, and the third ball valves 43 on the other third oil passage 33 are closed; the fourth ball valve 44 on one of the two fourth oil passages 34 is opened, and the fourth ball valve 44 on the other fourth oil passage 34 is closed;

that is, the second main pump system is communicated with the second lift cylinder 210 through the third oil path 33 to provide lifting power for the second lift cylinder 210, and is communicated with the first lift cylinder 110 through the third oil path 33, the first backup oil path 35 and the first oil path 31 in sequence to provide lifting power for the first lift cylinder 110;

the second auxiliary pump system is communicated with the second bolt oil cylinder 220 through the fourth oil path 34 to provide plugging power for the second bolt oil cylinder 220, and the second auxiliary pump system is communicated with the first bolt oil cylinder 120 through the fourth oil path 34, the second spare oil path 36 and the second oil path 32 in sequence to provide plugging power for the first bolt oil cylinder 120; and the first lifting oil cylinder 110, the first bolt oil cylinder 120, the second lifting oil cylinder 210 and the second bolt oil cylinder 220 all return oil to the second oil return tank.

When the second hydraulic device 230 fails and cannot work, the opening and closing of each ball valve is adjusted accordingly, which is not described herein again.

In summary, in the hydraulic latch lifting system of the present invention, the first hydraulic device 130 is designed to communicate with the first lifting cylinder 110 through a first oil path 31, and the first hydraulic device 130 communicates with the first latch cylinder 120 through a second oil path 32; the second hydraulic device 230 is communicated with the second lift cylinder 210 through a third oil path 33, and the second hydraulic device 230 is communicated with the second latch cylinder 220 through a fourth oil path 34; the first oil passage 31 communicates with the third oil passage 33 through a first backup oil passage 35; the second oil passage 32 communicates with the fourth oil passage 34 through a second backup oil passage 36; therefore, when the first hydraulic device 130 or the second hydraulic device 230 fails, the second hydraulic device 230 or the first hydraulic device 130 can provide power for the first lifting cylinder 110, the second lifting cylinder 210, the first bolt cylinder 120 and the second bolt cylinder 220 at the same time, so that the lifting power is continuously provided for the pile leg, the continuous lifting operation is ensured, and the working efficiency is effectively improved.

The above is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, several modifications and substitutions can be made without departing from the technical principle of the present invention, and these modifications and substitutions should also be regarded as the protection scope of the present invention.