CN221500546U - Bridge maintenance hanging ladder equipment - Google Patents

Abstract

The utility model relates to the technical field of bridge maintenance, in particular to bridge maintenance hanging ladder equipment which comprises two-sided cantilever mechanisms, wherein two sides of the bottom of each of the two-sided cantilever mechanisms are respectively provided with a bridge deck supporting and traveling mechanism, the bottoms of the two bridge deck supporting and traveling mechanisms are respectively supported at the top of a current bridge deck, the left end and the right end of each of the two-sided cantilever mechanisms extend to the outer side above the current bridge deck, the bottoms of the two ends of each of the two-sided cantilever mechanisms are respectively and fixedly connected with a lifting position control unit, and the bottoms of each lifting position control unit are respectively and fixedly provided with a manned ladder unit. The bridge maintenance hanging ladder equipment adopts the movable portal frame and the bridge deck supporting travelling mechanism to realize the support of the whole structure, ensures that the middle part of the whole equipment is supported on the bridge deck for use, and simultaneously adopts a mode that both ends outwards extend to realize that maintenance personnel can be arranged at both ends to enter for maintenance or only one end of the maintenance personnel is required to be maintained when the bridge deck is maintained, so that the selectivity is stronger.

Description

Bridge maintenance hanging ladder equipment

Technical Field

The utility model relates to the technical field of bridge maintenance, in particular to bridge maintenance hanging ladder equipment.

Background

Over time, bridges may be affected by various factors, such as natural disasters, vehicle impacts, and the like. These factors may cause the bridge to be damaged to different degrees, for example, if maintenance is not performed in time, normal use of the bridge may be affected, and even safety accidents may be caused. Therefore, bridge maintenance is of great importance in ensuring the safety and normal use of bridges.

The traditional bridge maintenance is to ensure that the bridge is always in a normal working state, and the work of checking, detecting, evaluating and maintaining and reinforcing is carried out, and the maintenance work is generally completed by adopting a bridge maintenance ladder structure to assist a maintenance worker when the bridge maintenance is carried out at present.

For example, in patent document CN218203869U, a bridge maintenance hanging ladder is disclosed, and the main structure of the bridge maintenance hanging ladder includes a supporting frame, and further includes a first hanging ladder body, a second hanging ladder body, a workbench, a fixing plate, a weight box, a pulley, and a rope arranging adjusting mechanism, where the surface of the supporting frame is fixedly connected with the first hanging ladder body, the surface of the first hanging ladder body is slidably connected with the second hanging ladder body, the surface of the second hanging ladder body is fixedly connected with the workbench, the surface of the supporting frame is fixedly connected with the fixing plate, the upper surface of the fixing plate is fixedly connected with the weight box, the surface of the supporting frame is fixedly connected with the pulleys, the two pulleys are fixedly connected with the rope arranging adjusting mechanism, the rope arranging adjusting mechanism is fixedly connected with the second hanging ladder body, and both pulleys are mounted in cooperation with the rope arranging adjusting mechanism.

It can be seen that the mode that it mainly adopts unilateral to hang is that the staff hangs the ladder body through support frame, first string ladder body, second, enters into the workstation, through the double-end motor, the drum rotates, tightens up or loosen the cable wire, makes the second hang ladder body rise or descend, in a certain limit, can maintain the bridge of different co-altitude, through arranging the cable work, stability when further having improved the workstation and rising or descend is convenient for maintain the different horizontal position of bridge through universal wheel and handrail, has improved bridge maintenance and has hung the adaptability of ladder.

However, the single-side suspension mode is relatively poor in stability after the whole suspension is supported by simply depending on the overhanging of the fixing plate in the maintenance process, and the risk of lifting the lower part at the upper horizontal section easily exists after shaking occurs at the lower part; in addition, the hanging ladder structure can only carry out maintenance on the side part of the bridge within one side range when carrying out maintenance, the maintenance range is effective, the bridge of the same section needs to be carried out in two times repeatedly to complete the maintenance of the bridge sections on two sides, and the maintenance efficiency is relatively low.

Therefore, the utility model optimizes and improves the problems of maintenance support stability and maintenance efficiency in the existing bridge maintenance technology, and provides bridge maintenance hanging ladder equipment for better solving the problems in the prior art.

Disclosure of utility model

The utility model aims to solve one of the technical problems, and adopts the following technical scheme: the utility model provides a bridge maintenance hangs terraced equipment, includes two side cantilever mechanisms install a bridge floor respectively in two sides of the bottom of two side cantilever mechanisms and support running gear's bottom is all supported at current bridge floor top, two sides all stretch to the top outside of current bridge floor about two side cantilever mechanisms the both ends bottom of two side cantilever mechanisms respectively fixedly connected with lift accuse position unit, each lift accuse position unit's bottom is all fixed mounting has manned ladder unit two side cantilever mechanism's mid-mounting has the counter weight unit that shifts.

In any of the above schemes, preferably, the double-sided cantilever mechanism includes a horizontally disposed movable gantry, the bottoms of the vertical sections on both sides of the movable gantry are respectively and fixedly provided with a supporting seat, the bottoms of the supporting seats are respectively provided with a bridge deck supporting and traveling mechanism, the inner cavities at both ends of the movable gantry are respectively and fixedly provided with a horizontally extending cylinder group, the inner ends of the horizontally extending cylinder groups are fixedly disposed, and the outer ends of the horizontally extending cylinder groups are respectively and fixedly connected with the tops of the lifting position control units at corresponding positions.

In any of the above schemes, preferably, the bridge deck support travelling mechanism comprises a connection chassis fixedly mounted at the bottom of the support seat, two sides of the bottom of the connection chassis are respectively provided with a driving travelling wheel, the outer ends of wheel shafts of the two driving travelling wheels are connected with the output end of a driving travelling unit, the driving travelling unit is fixedly mounted on the outer side wall of the connection chassis, and the bottom of each driving travelling wheel is supported at the top of the bridge deck.

In any of the above schemes, preferably, the driving walking unit includes a driving motor fixedly mounted on an outer side wall of the connection chassis, a bevel gear reducer is fixedly mounted at a bottom of a motor casing of the driving motor, and an output end of the bevel gear reducer is connected to an outer end of an axle of the driving walking wheel at a corresponding position and is used for driving the driving walking wheel to operate.

In any of the above schemes, preferably, the horizontal stretching cylinder group is formed by two synchronous stretching cylinders which are relatively spaced and fixedly installed in corresponding inner cavities of the movable portal frame, the two synchronous stretching cylinders are in synchronous stretching states in the working state, the outer ends of piston rods of the synchronous stretching cylinders are respectively and fixedly connected to corresponding end faces of the side support shifting frame, and the lifting position control unit is fixedly installed at the bottom of the side support shifting frame.

In any of the above solutions, preferably, the lifting position control unit includes two vertically disposed multi-stage lifting cylinders, the top of each of the cylinder barrels of the multi-stage lifting cylinders movably extends into the mounting cavity of the side support displacement frame at the corresponding position and is fixedly connected with the bottom of a rotary position adjusting assembly, the bottom of the piston rod of each of the multi-stage lifting cylinders is fixedly mounted at one side of the outer end of the manned ladder unit at the corresponding position, and the two multi-stage lifting cylinders are in synchronous lifting states under the working state.

In any of the above schemes, preferably, the rotary positioning assembly includes a rotary disc horizontally disposed in a mounting cavity of the side support displacement frame, a rotating motor with large torque is fixedly mounted in the mounting cavity above the rotary disc, the top of a motor casing of the rotating motor is fixedly mounted on the side support displacement frame, a motor shaft of the rotating motor is fixedly connected with the top center of the rotary disc, a plurality of rigid support balls are movably clamped and mounted at uniform intervals along the circumference of the bottom of the rotary disc, the bottom of each rigid support ball is supported and abutted to the bottom of the mounting cavity, the top of a cylinder barrel of each multistage lifting cylinder movably passes through a central opening of the bottom of the side support displacement frame and extends into the mounting cavity, and the top of a cylinder barrel of each multistage lifting cylinder is integrally and fixedly mounted at the central top of the rotary disc.

In any of the above schemes, preferably, the manned ladder unit includes a manned frame horizontally disposed, a working space for supporting a maintenance person to stand is disposed inside the manned frame, a rigid hanging ladder is fixedly mounted at an outer end of the manned frame, and a lower portion of a vertical section of the rigid hanging ladder is fixedly connected with the manned frame.

In any of the above schemes, preferably, the shifting counterweight unit comprises a rigid sliding sleeve slidably connected with the periphery of the horizontal section of the movable portal frame in a clamped manner, a hanging steel wire rope is fixedly installed at the bottom of the rigid sliding sleeve, a hanging hook is fixedly installed at the bottom of the hanging steel wire rope, and the hanging hook is used for hooking the counterweight block.

Compared with the prior art, the utility model has the following beneficial effects:

1. The bridge maintenance hanging ladder equipment adopts the movable portal frame and the bridge deck supporting travelling mechanism to realize the support of the whole structure, ensures that the middle part of the whole equipment is supported on the bridge deck for use, and simultaneously adopts a mode that both ends outwards extend to realize that maintenance personnel can be arranged at both ends to enter for maintenance or only one end of the maintenance personnel is required to be maintained when the bridge deck is maintained, so that the selectivity is stronger.

2. Bridge maintenance hangs terraced equipment relies on two bridge decks to support running gear in the in-process of carrying out the maintenance and can realize driving whole equipment to shift along the advancing direction of bridge floor to reach the maintenance personnel who stands in the manned ladder unit inside of corresponding tip of fast control and follow the oxidation of removing and accomplish the key part of continuous bridge face bottom position department, improve the effect and the efficiency of maintenance.

3. The manned ladder units at the two ends of the bridge maintenance hanging ladder device can be close to or far away from the side part of the bridge deck in a telescopic state of the horizontal extension cylinder group at the corresponding end part, and meanwhile, the lifting control position can be completed under the action of the lifting control position unit, so that the lifting of the bridge maintenance hanging ladder device in the height direction is ensured to be controlled.

4. In consideration of the fact that people exist in the manned units at the two ends at different times, the shifting counterweight unit capable of shifting along the horizontal direction is arranged to realize that the counterweight can be used for carrying out counterweight at different positions of the movable portal frame, and stability of the whole equipment can be guaranteed no matter in single-side maintenance or double-side maintenance.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the drawings that are used in the embodiments will be briefly described below. Like elements or features are generally identified by like reference numerals throughout the drawings. In the drawings, the elements or components are not necessarily drawn to scale.

Fig. 1 is a schematic structural view of embodiment 1 of the present utility model.

Fig. 2 is a schematic structural view of embodiment 2 of the present utility model.

Fig. 3 is a schematic view showing the structure of the manned unit of embodiment 2 of the present utility model in an operating state.

In the figure, 1, bridge deck; 2. moving the portal frame; 3. a support base; 4. the chassis is connected; 5. driving a travelling wheel; 6. a driving motor; 7. a bevel gear reducer; 8. a synchronous telescopic cylinder; 9. a side support shifting frame; 10. a multi-stage lifting cylinder; 11. a mounting cavity; 12. a rotating disc; 13. a rotating electric machine; 14. a rigid support ball; 15. a central opening; 16. a manned frame; 17. a rigid hanging ladder; 18. a rigid sliding sleeve; 19. hanging a steel wire rope; 20. hanging hooks; 21. and (5) balancing weights.

Detailed Description

Embodiments of the technical scheme of the present utility model will be described in detail below with reference to the accompanying drawings. The following examples are only for more clearly illustrating the technical aspects of the present utility model, and thus are merely examples, and are not intended to limit the scope of the present utility model. The specific structure of the utility model is shown in fig. 1-3.

Example 1: the utility model provides a bridge maintenance hangs terraced equipment, includes two side cantilever mechanisms install a bridge floor respectively in two sides of the bottom of two side cantilever mechanisms and support running gear's bottom is all supported at current bridge floor 1 top, two sides all stretch to the top outside of current bridge floor 1 about two side cantilever mechanisms the both ends bottom of two side cantilever mechanisms respectively fixedly connected with lift accuse position unit, each lift accuse position unit's bottom all fixed mounting carries the people's ladder unit two side cantilever mechanisms's mid-mounting has the aversion counter weight unit.

The bridge maintenance hanging ladder equipment integrally adopts the double-sided cantilever mechanisms as an integral supporting structure in design, and is supported on the ground by virtue of bridge deck supporting travelling mechanisms at the bottoms of two sides, so that the stability of the whole structure is effectively ensured, and lifting position control units at two ends of the double-sided cantilever mechanisms can drive corresponding manned ladder units to realize lifting when lifting control is carried out, so that the purpose of controlling maintenance personnel entering the inside to lift can be achieved.

In any of the above schemes, preferably, the double-sided cantilever mechanism includes a horizontally disposed movable gantry 2, the bottoms of the vertical sections on both sides of the movable gantry 2 are respectively and fixedly provided with a supporting seat 3, the bottoms of the supporting seats 3 are respectively provided with a bridge deck supporting and traveling mechanism, the inner cavities at both ends of the movable gantry 2 are respectively and fixedly provided with a horizontally extending cylinder group, the inner ends of the horizontally extending cylinder groups are fixedly disposed, and the outer ends of the horizontally extending cylinder groups are respectively and fixedly connected with the tops of the lifting position control units at corresponding positions.

It should be noted that, the bridge deck supporting running mechanism of two side cantilever mechanisms wholly relies on the both sides bottom realizes the bridge connection and supports, guarantees the steady nature of whole support, and the horizontal extension jar group that installs fixedly respectively at the both ends of removal portal frame 2 simultaneously can realize connecting and horizontal accuse position, can link the lift accuse position unit of its tip when horizontal extension jar group stretches out and draws back and realize wholly being close to or keeping away from the bridge body to reach the manned unit of control bottom and carry out the purpose of maintenance to the bridge deck bottom of different positions department in follow-up maintenance work in-process.

In any of the above schemes, preferably, the deck support running mechanism includes a connection chassis 4 fixedly mounted at the bottom of the support base 3, two sides of the bottom of the connection chassis 4 are respectively provided with a driving running wheel 5, outer ends of wheel shafts of the two driving running wheels 5 are connected with an output end of a driving running unit, the driving running unit is fixedly mounted on an outer side wall of the connection chassis 4, and the bottom of each driving running wheel 5 is supported at the top of the deck 1.

The bridge deck supports running gear wholly and relies on the driving walking wheel 5 of bottom to support, also need utilize the operation of the drive walking unit who is connected with driving walking wheel 5 to drive whole driving walking wheel 5 and realize rotating the aversion along the advancing direction of bridge deck when advancing or backing simultaneously, and the speed of control aversion can be realized cooperating the maintenance personnel to the maintenance speed assorted of bridge deck 1 bottom.

In any of the above schemes, preferably, the driving walking unit includes a driving motor 6 fixedly installed on an outer side wall of the connection chassis 4, a bevel gear reducer 7 is fixedly installed at a bottom of a motor housing of the driving motor 6, and an output end of the bevel gear reducer 7 is connected to an outer end of an axle of the driving walking wheel 5 at a corresponding position and is used for driving the driving walking wheel 5 to operate.

The whole driving walking unit adopts the driving motor 6 as a driving piece, and the driving walking unit can output power to the wheel shaft of the driving walking wheel 5 at the horizontal end by means of reversing and decelerating of the bevel gear speed reducer 7, so that the smoothness of the whole driving walking wheel 5 during shifting and rotating can be ensured, and the sufficiency of rotating power is ensured.

In any of the above schemes, preferably, the horizontal stretching cylinder group is formed by two synchronous telescopic cylinders 8 which are relatively spaced and fixedly installed in corresponding inner cavities of the movable portal frame 2, the two synchronous telescopic cylinders 8 are in synchronous telescopic states in the working state, outer ends of piston rods of the synchronous telescopic cylinders 8 are respectively and fixedly connected to corresponding end faces of the side support shifting frame 9, and the lifting position control unit is fixedly installed at the bottom of the side support shifting frame 9.

When the horizontal stretching cylinder group stretches, the positioning can be realized through the cylinder barrel of the synchronous stretching cylinder 8 which is fixedly arranged in the corresponding inner cavity of the movable portal frame 2 from front to back at two opposite intervals, and the stretching and the bearing capacity in the vertical direction are realized by means of the two piston rods during stretching, so that the horizontal displacement and the timely locking of the lifting position control unit at the corresponding end part of the horizontal stretching cylinder group are ensured to be controlled.

In any of the above solutions, preferably, the lifting position control unit includes two vertically disposed multi-stage lifting cylinders 10, the top of each cylinder barrel of each multi-stage lifting cylinder 10 movably extends into the mounting cavity 11 of the side support displacement frame 9 at the corresponding position and is fixedly connected with the bottom of a rotary position adjusting assembly, the bottom of the piston rod of each multi-stage lifting cylinder 10 is fixedly installed at one side of the outer end of the elevator carrying unit at the corresponding position, and the two multi-stage lifting cylinders 10 are in synchronous lifting states under the working state.

The lifting position control unit is composed of two multi-stage lifting cylinders 10 which are arranged at intervals along the left-right direction, and the two multi-stage lifting cylinders adopt synchronous lifting states when working, so that the stable lifting position control and the timely locking of the manned ladder unit at the bottom of the two multi-stage lifting cylinders 10 can be driven through synchronous telescopic lifting when working.

In any of the above schemes, preferably, the rotary positioning assembly includes a rotary disc 12 horizontally disposed in a mounting cavity 11 of the side support displacement frame 9, a large torque rotary motor 13 is fixedly mounted in the mounting cavity 11 above the rotary disc 12, a top of a motor casing of the rotary motor 13 is fixedly mounted on the side support displacement frame 9, a motor shaft of the rotary motor 13 is fixedly connected with a top center of the rotary disc 12, a plurality of rigid support balls 14 are movably mounted at regular intervals along a circumference of the bottom of the rotary disc 12 in a clamped manner, bottoms of the rigid support balls 14 are supported and abutted to the bottom of the mounting cavity 11, a top of a cylinder barrel of each multistage lifting cylinder 10 is movably penetrated through a central opening 15 at the bottom of the side support displacement frame 9 and extends into the mounting cavity 11, and a top of a cylinder barrel of each multistage lifting cylinder 10 is integrally and fixedly mounted at a central top of the rotary disc 12.

It should be noted that, the rotary positioning assembly provided herein can play a role in effectively fixing and supporting the multi-stage lifting cylinder 10 and the manned unit at the bottom of the rotary positioning assembly, and the manned unit at the current bottom is controlled to rotate so as to achieve the purpose of conveniently supporting the upper and lower stations of the maintenance personnel, ensure the fluency of the personnel entering or climbing out, and realize the purpose of converting the stations.

In addition, even if the rotating disc 12 connected with the bottom of the rotating motor 13 can be driven to rotate by controlling the rotation 180 of the rotating motor 13 in the subsequent maintenance process of the bottom of the bridge deck, when the rotating disc 12 rotates, each rigid supporting ball 14 at the bottom of the rotating disc can play a role of guiding and supporting, so that the smoothness in rotation is ensured; in addition, when the rotary disk 12 rotates, the whole lifting position control unit and the manned ladder unit fixedly connected below the rotary disk are driven to rotate along with the rotary disk, so that the purpose of rapidly switching the stations of the manned ladder unit is achieved.

In any of the above schemes, preferably, the manned ladder unit includes a horizontally arranged manned frame 16, a working space for supporting a nursing staff to stand is provided inside the manned frame 16, a rigid hanging ladder 17 is fixedly mounted at the outer end of the manned frame 16, and the lower part of the vertical section of the rigid hanging ladder 17 is fixedly connected with the manned frame 16.

The manned ladder unit integrally depends on the manned frame 16 as a bearing platform, meanwhile, depends on the rigid hanging ladder 17 as a connecting piece and is used by a ladder with an upper station and a lower station, and the whole rigid hanging ladder 17 is formed by welding high-strength alloy steel, so that the whole rigid hanging ladder unit is high in overall structural strength and good in bearing performance.

Example 2: compared with embodiment 1, this embodiment differs in that:

The shifting counterweight unit comprises a rigid sliding sleeve 18 which is connected with the periphery of the horizontal section of the movable portal frame 2 in a sliding manner in a clamping manner, a hanging steel wire rope 19 is fixedly arranged at the bottom of the rigid sliding sleeve 18, a hanging hook 20 is fixedly arranged at the bottom of the hanging steel wire rope 19, and the hanging hook 20 is used for hooking a counterweight 21.

Considering that when single-side maintenance is carried out, only when a maintenance person enters the inside of a single manned unit, the maintenance person can be shifted by controlling one side far away from the current manned unit, and meanwhile, the corresponding hooking balancing weights 21 are configured and installed to realize the purpose of adjusting the gravity center and ensuring the stability of the whole structure.

The specific working principle is as follows: the whole bridge maintenance hanging ladder equipment integrally adopts the double-side cantilever mechanisms as an integral supporting structure in design, and supports the travelling mechanism on the ground by means of bridge deck supporting at the bottoms of the two sides, so that the stability of the whole structural support is effectively ensured, and lifting position control units at the two ends of the double-side cantilever mechanisms can drive corresponding manned ladder units to realize lifting when lifting control is performed, so that the purpose of controlling maintenance personnel entering the inside to lift can be achieved. In addition, adopt to remove portal frame 2 and bridge floor and support running gear and realize the support of whole structure, guarantee that the middle part of whole equipment supports and uses on the bridge floor, adopt the mode realization that both ends all outwards extend simultaneously can select both ends to arrange maintenance personnel to get into to carry out maintenance or only carry out maintenance at wherein one end when carrying out the maintenance of bridge floor, the selectivity is stronger. In the maintenance process, two bridge deck supporting travelling mechanisms are started to drive the whole equipment to shift along the travelling direction of the bridge deck, so that maintenance personnel standing in the manned ladder unit at the corresponding end part can be rapidly controlled to follow the movement and complete the oxidization of key parts at the bottom part of the continuous bridge deck, and the maintenance effect and efficiency are improved.

The manned ladder units at two ends of the bridge maintenance hanging ladder device can be close to or far away from the side part of the bridge deck in a telescopic state of the horizontal stretching cylinder group at the corresponding end part, and meanwhile, the lifting control position can be completed under the action of the lifting control position unit, so that the lifting of the bridge maintenance hanging ladder device in the height direction is ensured to be controlled; the manned units at the two ends have different conditions, so that the shifting counterweight unit capable of shifting along the horizontal direction is arranged to realize that the counterweight can be used for carrying out counterweight at different positions of the movable portal frame 2, and the stability of the whole equipment can be ensured no matter in single-side maintenance or double-side maintenance.

The above embodiments are only for illustrating the technical solution of the present utility model, and not for limiting the same; although the utility model has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the corresponding technical solutions; any alternative modifications or variations to the embodiments of the present utility model will fall within the scope of the present utility model for those skilled in the art.

The present utility model is not described in detail in the present application, and is well known to those skilled in the art.

Claims (9)

1. Bridge maintenance hangs terraced equipment, its characterized in that: including two side cantilever mechanisms install a bridge floor respectively in two sides of the bottom of two side cantilever mechanisms supports running gear's bottom all supports at current bridge floor top, two sides all stretch to the top outside of current bridge floor about two side cantilever mechanisms the both ends bottom of two side cantilever mechanisms respectively fixedly connected with lift accuse position unit, each lift accuse position unit's bottom all fixed mounting has manned ladder unit two side cantilever mechanisms's mid-mounting has the aversion counter weight unit.

2. A bridge maintenance hanging ladder apparatus according to claim 1, characterized in that: the double-side cantilever mechanism comprises a movable portal frame which is horizontally arranged, supporting seats are respectively and fixedly arranged at the bottoms of vertical sections at two sides of the movable portal frame, bridge deck supporting travelling mechanisms are respectively arranged at the bottoms of the supporting seats, horizontal extension cylinder groups are respectively and fixedly arranged in inner cavities at two ends of the movable portal frame, the inner ends of the horizontal extension cylinder groups are fixedly arranged, and the outer ends of the horizontal extension cylinder groups are respectively and fixedly connected with the tops of lifting position control units at corresponding positions.

3. A bridge maintenance hanging ladder apparatus according to claim 2, characterized in that: the bridge deck support running gear includes fixed mounting be in the connection chassis of supporting seat bottom the bottom both sides of connection chassis are installed respectively and are driven the walking wheel, two the outer end of the shaft of driving the walking wheel all is connected with the output of a drive running unit, drive running unit fixed mounting is in on the lateral wall of connection chassis, the bottom of each driving the walking wheel all supports at bridge deck top.

4. A bridge maintenance hanging ladder apparatus according to claim 3, characterized in that: the driving walking unit comprises a driving motor fixedly arranged on the outer side wall of the connecting chassis, a bevel gear reducer is fixedly arranged at the bottom of a motor shell of the driving motor, and the output end of the bevel gear reducer is connected with the outer end of a wheel shaft of the driving walking wheel at a corresponding position and is used for driving the driving walking wheel to operate.

5. The bridge maintenance hanging ladder apparatus of claim 4, wherein: the horizontal stretching cylinder group comprises two synchronous stretching cylinders which are oppositely spaced and fixedly arranged in corresponding inner cavities of the movable portal frame, the two synchronous stretching cylinders are in synchronous stretching states in a working state, the outer ends of piston rods of the synchronous stretching cylinders are respectively and fixedly connected to corresponding end faces of the side support shifting frame, and the bottom of the side support shifting frame is fixedly provided with the lifting position control unit.

6. The bridge maintenance hanging ladder apparatus of claim 5, wherein: the lifting position control unit comprises two vertically arranged multi-stage lifting cylinders, the top of each cylinder barrel of each multi-stage lifting cylinder movably extends into the mounting cavity of the side support shifting frame at the corresponding position and is fixedly connected with the bottom of the rotary position adjusting assembly, the bottom of the piston rod of each multi-stage lifting cylinder is fixedly arranged at one side of the outer end of the manned ladder unit at the corresponding position, and the two multi-stage lifting cylinders are in synchronous lifting states under the working state.

7. The bridge maintenance hanging ladder apparatus of claim 6, wherein: the rotary positioning assembly comprises a rotary disc horizontally arranged in a mounting cavity of the side support shifting frame, a rotary motor with large torque is fixedly arranged in the mounting cavity above the rotary disc, the top of a motor shell of the rotary motor is fixedly arranged on the side support shifting frame, a motor shaft of the rotary motor is fixedly connected with the top center of the rotary disc, a plurality of rigid support balls are movably clamped and installed at equal intervals along the circumference of the bottom of the rotary disc, the bottoms of the rigid support balls are all supported and abutted to the bottom of the mounting cavity, the top of a cylinder barrel of each multistage lifting cylinder movably penetrates through a central opening in the bottom of the side support shifting frame and stretches into the mounting cavity, and the top of the cylinder barrel of each multistage lifting cylinder is integrally and fixedly arranged at the center top of the rotary disc.

8. The bridge maintenance hanging ladder apparatus of claim 7, wherein: the manned ladder unit comprises a manned frame which is horizontally arranged, a working space for supporting and protecting personnel to stand is arranged in the manned frame, a rigid hanging ladder is fixedly arranged at the outer end of the manned frame, and the lower part of the vertical section of the rigid hanging ladder is fixedly connected with the manned frame.

9. The bridge maintenance hanging ladder apparatus of claim 8, wherein: the shifting counterweight unit comprises a rigid sliding sleeve which is connected with the periphery of the horizontal section of the movable portal frame in a sliding manner in a clamping manner, a hanging steel wire rope is fixedly arranged at the bottom of the rigid sliding sleeve, a hanging hook is fixedly arranged at the bottom of the hanging steel wire rope, and the hanging hook is used for hooking the counterweight block.