1. The utility model provides a three leaf round pin hinge formula bridge column mound creeping formwork devices which characterized in that: the template of the bridge cylindrical pier (5) is formed by hinging a three-leaf circular arc template (1), a through long pin shaft pin section (9) and a pin shaft section (10) through a pin (7) and a shaft combination into a template structure, a special clamp device (26) for pulling/pressing through a long pin shaft is arranged at the upper end of the through long combined pin shaft template, a 0-layer platform (23) is arranged at the upper end of the template, a-1-layer platform (13) is arranged at the lower end of the template, the 0-layer platform (23) is connected with the-1-layer platform (13) through an upright post (14), a cylindrical wedge-shaped upper support (22) is arranged at the inner side of the lower end of the 1-layer platform (13), a three-leaf pin hinged hoop lower support (29) is arranged at the lower end of the cylindrical wedge-shaped upper support (22), a hydraulic jacking jack (17) is arranged at the lower end of the 1-layer platform (13), and the upper end of the hydraulic jack (17) is hinged with the-1-layer platform (13), the lower end is fixed on a-2-layer platform (19), the-2-layer platform (19) is connected with a three-blade pin hinge type lifting hoop (30) in a rigid and flexible combined mode through a lifting hoop-2-layer platform consolidation device (21) and a suspension rope (20), one side of the-2-layer platform (19) is connected with a ladder climbing channel system (4), and the upper end of the ladder climbing channel system is connected with an upright steel pipe (14) through a sliding guide device.

2. The three-leaf pin hinge type bridge column pier creeping formwork device according to claim 1, characterized in that: the three-blade circular arc template (1) consists of a three-blade circular arc template block, two shaft pins (7) and a through long combined pin shaft (10); the pin (7) is connected with two hinge interfaces, one shaft combined through long pin shaft (10) is connected with the other hinge interface, and the lowest end of the template through long combined pin shaft (10) is provided with 2 protective bolts (11) for connection.

3. The three-leaf pin hinge type bridge column pier creeping formwork device according to claim 1, characterized in that: the cylindrical wedge-shaped middle fulcrum conversion upper support (22) is fixedly connected to the bottom end of the-1-layer platform (13), the wedge-shaped angle is larger than 60 degrees and is consistent with the wedge-shaped angle of the three-leaf hinge type hoop wedge-shaped middle fulcrum conversion lower support (29); the three-leaf pin hinge type anchor ear wedge-shaped middle fulcrum conversion lower support (29) is composed of 2 pins (7), a lower support arc wedge-shaped module (32) and 1 locking bolt (25).

4. The three-leaf pin hinge type bridge column pier creeping formwork device according to claim 1, characterized in that: the three-blade pin hinge type embracing lifting hoop (30) is composed of 3 blade circular arc-shaped modules, 2 shaft group pins (7) and 3 hoop bolts (18); the 1-blade circular arc module is fixedly connected with the-2 layers of platforms, and the other 2-blade circular arc module blocks are movably connected with the-2 layers of platforms.

5. The three-leaf pin hinge type bridge column pier creeping formwork device according to claim 1, characterized in that: the ladder stand channel system (4) is fixed on one side of a-2-layer platform (19) through hinging, the ladder stand channel system (4) and the-2-layer platform (19) are lifted synchronously, and the sliding bidirectional guide device (16) is fixedly connected to the ladder stand channel system (4) and vertically slides along the upright post steel pipe (14) to realize the bidirectional guide function.

6. The three-leaf pin hinge type bridge column pier creeping formwork device according to claim 1, characterized in that: the through long pin shaft (10) is composed of pin sections (9) and pin rod sections (31), and the middle of each pin section is provided with a hole.

7. The three-leaf pin hinge type bridge column pier creeping formwork device according to claim 1, characterized in that: the upper end of the through long pin shaft is provided with a special clamp device (26) for pulling/pressing the through long pin shaft and a hydraulic pulling and pressing jack (33).

8. The three-leaf pin hinge type bridge column pier creeping formwork device according to claim 1, characterized in that: the connection of the-2 layers of platforms (19) and the three-blade hooping hoop (30) adopts a rigid connection of one-blade hooping hoop block and the-2 layers of platforms (19) through a hooping hoop-2 layers of platform consolidation device, and the other two-blade hooping hoop and the-2 layers of platforms (19) adopt a suspension rope (20) to carry out a flexible connection, namely a rigid-flexible combined structural system.

Background

The design of highway bridges and municipal overhead bridges in China is generally that cylindrical piers are adopted when the height of pier columns of the bridges is about 30 meters (unless special landscape requirements), and the construction of the cylindrical piers with the height of 30 meters and below is very common. The construction method has been used for decades, and the connection mode of the buckling bolts of the two-leaf semicircular template blocks is not changed although the template structure and the construction platform are slightly improved.

The two-blade template block buckling bolt connecting system has the following defects during construction: 1. the device does not have self-climbing and self-descending functions, and lifting equipment is required to be lifted for installing and removing templates of different sections of the same pier; 2. the quantity of the two-blade template block buckling bolts is large, and after repeated use, the bolts have potential safety hazards such as fatigue, thread damage and the like; 3. when each section of pier template is installed/dismantled, all the buckled bolts need to be connected/dismantled, which wastes time and labor; 4. when the fastening bolts on the two sides of the template are removed, because no platform or channel is provided, an overhead hanging belt is needed for climbing and removing by operation workers, the operation environment is severe, the potential safety hazard is large, and the efficiency is low; 5. because the operation workers do not have ladder climbing channels, the operation workers are generally hoisted by a crane and are hoisted, the cost is high, and the potential safety hazard is large; 6. because the work amount of the column type pier is less, the building of the surrounding safety enclosure and the ladder climbing channel needs larger measure cost and longer construction period, and the construction unit is difficult to bear.

The technology for constructing the cylindrical pier is technically innovative, and essentially achieves progress benefit, safety, controllability and improvement of the operation environment.

Disclosure of Invention

The technical problem to be solved by the invention is to overcome the defects of the existing cylindrical pier construction method and device, and provide a novel cylindrical pier construction template device, which is a three-blade pin hinge type bridge cylindrical pier creeping formwork device for realizing high construction efficiency, fast progress, safe and reliable process, improving construction operation environment, reducing labor intensity and saving construction cost.

The technical scheme for solving the problems is as follows: the three-blade pin hinge type climbing formwork device for the bridge column pier is divided into a formwork system, a platform system, a hydraulic jacking and fulcrum conversion system and a climbing ladder channel system. The template system consists of three-leaf circular arc-shaped template blocks, two pins and one through long pin shaft; the platform system provides a 3-layer safe and reliable working platform, and the template system is arranged in a-1 layer and a 0 layer and can move in the platform; the hydraulic jacking and fulcrum conversion system can quickly and safely realize the ascending and descending of the whole structural system and fulcrum conversion without the cooperation of other hoisting equipment; the ladder climbing passage system realizes synchronous lifting through the connecting platform, and the lengthened ladder climbing section can be hung below the ladder climbing passage system after the ladder climbing passage system is lifted to reach the height of a standard section.

As a preferred technical scheme, the template system is compared with a current universal two-leaf bolt knot type structure by a three-leaf pin hinge type structure, three-leaf template blocks of the three-leaf pin hinge type structure can rotate and translate around two shafts respectively, the degree of freedom is increased, and the template demoulding function can be realized after the constraint of one pin is removed.

As a preferred technical scheme, the three-blade pin hinge type structure system is provided with a through long combined pin shaft, and the combined pin is divided into a pin section and a pin rod section.

As a preferred technical scheme, the hydraulic jacking and fulcrum conversion system realizes the self-climbing and descending functions of the whole structural system without the cooperation of other hoisting equipment.

As a preferable technical scheme, the middle fulcrum conversion device is divided into an upper support and a lower support. The upper support is in a circular structure and is fixed at the bottom end of the-1-layer platform; the lower support is a three-leaf pin hinged vertical wedge-shaped inclined plane circular hoop structure, is movably hung below the-1 layer platform and is locked at the corresponding pier stud part through bolts when needed.

As a preferable technical scheme, the ladder climbing channel system is fixedly connected with a-2-layer platform, is lifted and lowered synchronously with the-2-layer platform, and is lengthened (dismantled) at the bottom when the ladder climbing channel system is lifted (lowered) to reach the height of a standard section. Compared with the existing common ladder stand channel erection which needs to be erected at the upper part in high altitude, the ladder stand channel erection device does not need the cooperation of other hoisting equipment and high altitude operation, and is more efficient and safer.

As a preferable technical scheme, the sliding guide device provides a guide function when the 0-floor and-1-floor platforms are lifted, and conversely provides a guide function for the ladder climbing passage system when the-2-floor platforms are lifted.

As a preferred technical scheme, the rigid and flexible combined connection mode of the-2-layer platform and the holding and lifting hoop can facilitate quick and convenient demoulding of the holding and lifting hoop and meet the structural stress requirement of the-2-layer platform and the holding and lifting hoop.

The invention also provides a construction method of the three-blade pin hinge type bridge cylindrical pier creeping formwork device, which comprises the following steps:

s1 creeping formwork device for mounting first section pier stud

a. Integrally hoisting the assembled-2 layers of platforms and the holding and lifting hoops into the bridge position of the pier column with the pier column reinforcing steel bars;

b. connecting and fixing the channel section of the reinforced channel section with the-2 layers, and building the rest upper ladder climbing channel on the reinforced channel section;

c. the assembled-1-layer platform is placed above the-2-layer platform, the upper part of a jacking jack is connected with the-1-layer platform, and the jack is retracted to the lowest position;

d. placing the assembled template system above the holding hoop, and connecting a horizontal flange at the bottom of the template and a flange at the upper end of the holding hoop into a whole by using bolts;

e. mounting a 0-layer platform, an upright post and a sliding guide device;

s2 casting first section pier stud concrete

After the first section pier stud creeping formwork device is installed, straightening a formwork, checking a steel bar project, pulling three positioning cables with intervals of 120 degrees above the formwork, and pouring first section pier stud concrete;

s3 reinforcing cage for installing standard section pier stud

Installing pier column reinforcement cages of standard sections at proper time when the concrete is finally set and has equal strength, and pulling three positioning cables with intervals of 120 degrees above the reinforcements;

s4 climbing of climbing formwork device

a. The strength of newly poured concrete is more than 7.5Mpa, the time is not less than 12 hours, and the bolts connected with the horizontal flanges of the lifting hoops at the bottom of the template are removed;

b. pulling a pin segment on the through long pin shaft by using special clamp equipment for pulling/pressing the through long pin shaft at the top of the template, and removing 2 protection bolts below the through long pin shaft to realize template demoulding;

c. jacking a-1-layer platform (with a 0-layer platform and a template system) for one stroke by using a hydraulic jacking jack;

d. mounting the middle fulcrum conversion lower support at the bottom of the-1-layer platform, and screwing a pre-tightening bolt;

e. jacking jacks return oil, slowly dropping a platform at the layer-1 and the like, and converting an upper support to a lower support by using a middle fulcrum to finish the first conversion of a stressed fulcrum;

f. 3 locking bolts of the bottom holding hoop are removed, the plastic base plate is taken out, and the holding hoop is demoulded;

g. the jacking jack continues to return oil, the-2-layer platform, the holding lifting hoop and the ladder climbing channel are lifted for a stroke, 3 pre-tightening bolts of the holding lifting hoop are tightened, the tightening bolts of the middle fulcrum conversion lower support are loosened, and a standard climbing process is completed;

h. c, repeating the step c-g, climbing the whole system to a corresponding preset elevation, aligning the template, screwing 2 protection bolts below the through long pin shaft of the template, pressing the through long pin shaft back to a pin segment (in situ) by using special fixture equipment for pulling/pressing the through long pin shaft, completing template installation, and waiting for pouring pier upright column concrete;

s5, lengthening and erecting the channel

a. After the whole set of system is lifted to reach the height of a standard channel segment, a standard channel segment is additionally connected below the channel;

b. after the top of the 2-layer platform is lifted to 10 meters above the ground, an auxiliary column is arranged at the 10-meter pier column to connect the ladder climbing channel with the pier column;

s6 dismantling of the whole system

a. Repeating the steps S2-S5 to complete the construction of one bridge pier stud;

b. reversely operating S4-S5, lowering the whole system to the ground, and decomposing and dismantling the system on the ground;

c. if the channel system needs to be used for remaining a construction bent cap, the 0-layer platform, the-1-layer platform and the template system can be detached in situ, and the-2-layer platform and the hoop are reserved.

The invention has the following beneficial effects:

1. the invention applies the creeping formwork concept to the column template system of the column pier by combining the anchor ear fulcrum principle, solves the self-climbing (descending) function of the template system, and saves a large amount of hoisting equipment matched with the platform class cost;

2. the revolutionary innovation of the three-leaf pin hinge type structure solves the problem that workers need to climb on the two side faces of the template to dismount the connecting bolt when the two-leaf hinge bolt connecting type template system is dismounted, the constraint (demoulding) of the template and the template system (resetting) can be easily released and fastened again only by pulling/pressing the top of the template by using a patent clamp, and the human-oriented concept of safety is embodied;

3. the channel ladder stand is connected with a-2-layer platform, and the synchronous lifting concept solves the problems that the traditional ladder stand channel needs to be heightened at the top when being erected, a large amount of overhead work exists, hoisting machinery is needed to be matched, the difficulty is high when pier columns are higher, and the assembled standard ladder stand channel section is only required to be lengthened at the lower part when the height of each standard section is lifted, so that the operation is fast and safe;

4. after the sleeve is tied on the pier stud, the sleeve can fall to the ground and then be disassembled, so that the potential safety hazard of in-situ high-altitude disassembly is reduced, and the safety guarantee is improved from the technical essence;

5. in a word, the application of the system greatly improves the construction efficiency of the pier stud, greatly reduces the construction measure cost, is safer and more controllable, and greatly improves the operation environment of constructors.

Drawings

FIG. 1 is a schematic diagram of the system of the present invention.

Fig. 2 is a schematic diagram of the front side of the template system structure.

Fig. 3 is a schematic cross-sectional view of the construction of the formwork system.

FIG. 4 is a cross-sectional view of the structure at the-1-tier plateau.

Fig. 5 is a schematic structural view of the hydraulic jacking and fulcrum conversion system of the present invention.

FIG. 6 is a schematic view of a combination structure of a 0-layer stage and a-1-layer stage.

Fig. 7 is a schematic structural view of the intermediate fulcrum conversion upper support.

Fig. 8 is a schematic structural view of the intermediate fulcrum conversion lower support.

Fig. 9 is a schematic view of a ladder passage section structure.

Fig. 10 is a schematic view of a combined structure of the combined full-length pin shaft of the invention.

Fig. 11 is a schematic structural view of a template leaf block spigot device.

In the figure: 1. a template system; 2. a platform system; 3. a hydraulic jacking and fulcrum conversion system; 4. a ladder climbing passageway system; 5. a pile foundation; 6. a template block; 7. a pin; 8. a pin hinged support; 9. a combination pin segment; 10. combining a through long pin shaft; 11. protecting the bolt; 12. a template blade spigot device; 13. -1 layer of platforms; 14. a column steel pipe; 15. a concrete pump pipe; 16. a bidirectional guide device; 17. a hydraulic jack; 18. a hoop bolt; 19. -a 2-layer platform; 20. hanging a pull rope; 21. a hoop-2-layer platform consolidation device is lifted; 22. an upper support of the middle conversion fulcrum; 23.0 layers of platforms; 24.0 layers and-1 layer of platform drawknot ropes; 25. the middle conversion lower support pre-tightening bolt; 26. special fixture equipment for the full-length pin shaft; 27. male rabbets of the template blade blocks; 28. female rabbets of the template blade blocks; 29. a middle conversion fulcrum lower support; 30. a three-leaf hoop for holding; 31. a combination pin segment; 32. the circular arc wedge-shaped module of the lower support; 33. and (5) hydraulically pulling and pressing the jack.

Detailed Description

The present invention will be described in further detail below with reference to the drawings and examples, but the present invention is not limited to the embodiments described below.

As shown in fig. 1, the three-leaf pin hinge type cylindrical high pier climbing formwork system consists of a formwork system, a platform system, a hydraulic jacking and fulcrum conversion system and a ladder climbing channel system.

As shown in figure 2, each section of template consists of a three-leaf circular arc template block (6), two shaft pins (7) and a shaft combined through long pin shaft (10).

As shown in fig. 2-4, the three-leaf pin hinge type template structure is compared with the current general two-leaf bolt knot type template structure, the three-leaf template blocks of the three-leaf pin hinge type structure can rotate and translate around two shafts respectively, the degree of freedom is increased, and even if the provided movable gap is very small after a pin section is removed or elevated by a full-length pin shaft, the three-leaf template blocks can translate and rotate respectively, so that the demoulding function can be realized quickly.

As shown in fig. 10, the three-leaf pin hinge type template structure system of the present invention is provided with a through long combined pin shaft (10) which is divided into a pin segment (9) and a pin rod segment (31). The pin segment (9) is thick, the pin rod segment (31) is thin, the pin segment (9) is used for effectively and tightly buckling the three-blade template into a whole, and the pin rod segment (31) provides a movable gap for demoulding of the template. The combined through long pin shaft (10) extends to the top of the template, and a special hydraulic pulling/pressing through long pin shaft clamp device (26) arranged at the top end of the template can simply, conveniently and quickly pull up or press down the length of a pin section to relieve the overall constraint of the template, while the two-blade bolt type template structure can relieve the overall constraint of the template only by dismantling all bolt bolts along the two vertically opposite sides of the template by an operation worker. In the same way, when the templates are assembled again, the whole constraint of the templates can be formed again only by pressing the through long pin back to the original position, so that a stable structure is formed.

As shown in fig. 5, the hydraulic jacking and fulcrum conversion system is composed of a jacking jack (17), a middle fulcrum conversion lower support (29), a middle fulcrum conversion upper support (22) and a hoop (30). The hydraulic jacking and fulcrum conversion system realizes the self-climbing and descending functions of the whole structure system without the cooperation of other hoisting equipment. The upper end of a hydraulic jacking jack (17) is hinged at a-1 layer platform (13), the bottom of the hydraulic jacking jack is fixedly connected at a-2 layer platform (19), the-2 layer platform (19) is connected with a bottom holding lifting hoop (30), the holding lifting hoop (30) is attached to a bridge pier column through pretightening force of a bolt (18) to provide a bottom end acting point for jacking operation, the 1 layer platform (13) supports a template system (1) to drive the template system to synchronously lift and lower, and the whole structure system is lifted (lowered) to a preset high position through a fulcrum conversion device in multiple jacking (lowering) strokes.

As shown in fig. 7-8, the middle fulcrum conversion device is divided into an upper support (22) and a lower support (29), the upper support (22) is a circular structure and is fixed at the bottom end of the-1-layer platform (), the inner side of the upper support (22) is a circular wedge-shaped inclined plane, and the upper part is small and the lower part is large; the lower support (29) is a three-blade pin hinged vertical wedge-shaped inclined plane circular hoop structure which is small at the top and large at the bottom, and the angle of the vertical wedge-shaped inclined plane is consistent with that of the upper support. Three leaf round pin articulated vertical wedge inclined plane circular staple bolt structure undersetting (29), three leaf hoop blocks can rotate around the hinge respectively equally, possess more degrees of freedom, more can laminate the surface of bridge mound than two leaf formula staple bolts, and the conjugation rate is higher. The upper and lower support structures of the vertical wedge-shaped inclined plane circle play a role in preventing falling, and the fulcrum conversion process is safer and more reliable.

As shown in fig. 9, the ladder passage system is composed of a plurality of standard ladder stages, a fixed ladder stage and a transition ladder stage. The fixed section ladder stand of the ladder stand channel system is fixedly connected with a-2-layer platform (19), and is lifted and lowered synchronously with the-2-layer platform (19), and when the lifting (lowering) reaches the height of a standard section, the bottom of the fixed section ladder stand is lengthened (dismantled) to the standard section. If the height of the ladder is less than the height of one standard section, the transition ladder stand section is adopted to match with the lifting hoop to lift the ladder stand to ensure that the bottom of the ladder stand is contacted with the ground, so that the stress safety of the ladder stand is ensured. Compared with a common ladder stand top lengthening and heightening mode, the bottom lengthening standard knot mode is more convenient and faster, does not need the cooperation of hoisting equipment, reduces a large amount of potential hazards of high-altitude operation and saves construction cost.

As shown in fig. 1 to 11, the construction method of the three-leaf pin-hinged bridge cylindrical pier creeping formwork device comprises the following implementation steps:

s1 creeping formwork device for mounting first section pier stud

a. Integrally hoisting the assembled-2-layer platform (19) and the clasping and lifting hoop (30) into the bridge position of the pier column with the pier column reinforcing steel bars;

b. connecting and fixing the ladder stand fixing section with a-2-layer platform (19), and building the rest ladder stand channel on the ladder stand fixing section by using a ladder stand standard section;

c. the assembled-1-layer platform (13) is placed above the-2-layer platform (19), the upper part of a jacking jack (17) is connected with the-1-layer platform (13), and the jack (17) is retracted to the lowest position;

d. the assembled template system (1) is arranged above the lifting hoop (30), and a horizontal flange at the bottom of the template is connected with a flange at the upper end of the lifting hoop (30) into a whole by bolts;

e. and a 0-layer platform (23), a vertical column steel pipe (14) and a sliding guide device (16) are installed.

S2 casting first section pier stud concrete

After the first section pier stud creeping formwork device is installed, straightening the formwork, checking the steel bar project, pulling three positioning cables with intervals of 120 degrees above the formwork, and pouring the first section pier stud concrete.

S3 reinforcing cage for installing standard section pier stud

And (3) installing a pier column reinforcement cage of a standard section at the right time when the concrete is finally set and has the same strength, and pulling three positioning cables at intervals of 120 degrees above the reinforcement cage.

S4 climbing of the whole climbing formwork system

a. The strength of newly poured concrete is more than 7.5Mpa, the time is not less than 12 hours, and the bolts connected with the horizontal flanges of the hooping and lifting hoops at the bottom of the template (1) are removed;

b. pulling a pin segment on the through long pin shaft (10) by using special pulling/pressing clamp equipment (26) for the through long pin shaft at the top of the template, and removing 2 protection bolts (11) below the through long pin shaft to realize template demoulding;

c. a hydraulic jack (17) is used for jacking a layer-1 platform (13) (with a layer-0 platform and a template system) for a stroke;

d. mounting a middle fulcrum conversion lower support (29) at the bottom of the-1-layer platform (13), and screwing a pre-tightening bolt (25);

e. jacking jacks (17) return oil, slowly dropping a-1-layer platform (13) and the like, and converting an upper support (22) to a lower support (29) through a middle fulcrum to complete the first conversion of a stressed fulcrum;

f. 3 locking bolts (18) of the bottom holding lifting hoop (30) are removed, the plastic base plate (34) is taken out, and the holding lifting hoop (30) is demoulded;

g. the jacking jack (17) continues to return oil, the-2-layer platform (19), the embracing lifting hoop (30) and the ladder climbing channel system (4) are lifted for a stroke, 3 pre-tightening bolts (18) of the embracing lifting hoop (30) are tightened, the tightening bolts (25) of the middle fulcrum lower support are loosened, and a standard climbing process is completed;

h. and repeating the step c-g, climbing the whole system to a corresponding preset elevation, aligning the template, screwing 2 protection bolts (11) below the through long pin shaft of the template, pressing the through long pin shaft (10) back to a pin segment (in situ) by using special fixture equipment for pulling/pressing the through long pin shaft, completing template installation, and waiting for pouring pier column concrete.

S5 ladder passage lengthening erection

a. After the whole set of system is jacked to reach the height of a section of a standard ladder climbing channel, a standard ladder climbing section (4) is additionally connected below the ladder climbing channel;

b. after the 2-layer platform (19) is lifted to be 10 meters higher than the ground, an auxiliary column is arranged at the 10-meter pier column to connect the ladder climbing channel with the pier column.

S6 dismantling of the whole system

a. Repeating the steps S2-S5 to complete the construction of one bridge pier stud;

b. reversely operating S4-S5, lowering the whole system to the ground, and decomposing and dismantling the system on the ground;

c. if the channel system needs to be used for remaining a construction capping beam, the 0-layer platform (23), -1-layer platform (13) and the template system (1) can be dismantled in situ, and the ladder climbing channel system (4), -2-layer platform (19) and the holding lifting hoop (30) are reserved.

Through simulation comparison with the currently universal two-leaf bolt knot type circular pier stud template use example (pier stud diameter is 1.8m, pier stud height is 32 m, construction is divided into four sections), the two-leaf bolt knot type template structure approximately needs to be measured with cost of 3.6 ten thousand yuan for 10 days of construction period, the three-leaf pin hinge type template structure approximately needs to be measured with cost of 1.4 ten thousand yuan for 5 days of construction period, meanwhile, the labor intensity of construction workers of the three-leaf pin hinge type template structure is greatly reduced, and the potential safety hazard of process high-altitude operation is also greatly reduced.

The foregoing shows and describes the general principles and features of the present invention, together with the advantages thereof. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are intended to illustrate the principles of the invention, but rather that various changes and modifications, such as four-leaf pin hinge, etc., may be made without departing from the spirit and scope of the invention as defined by the appended claims. The scope of the invention is defined by the appended claims and equivalents thereof.