Horizontal rotating pedestrian bridge system driven by single-point motor pin gear

Abstract

The application discloses a single-fulcrum motor pin gear driven horizontal rotary pedestrian bridge system and belongs to the technical field of complete mechanical and electrical systems of openable pedestrian bridges. In view of the technical defects of the traditional hydraulic drive pedestrian bridge, such as oil leakage polluting the river, exposed equipment damaging the ancient building style, unilateral partial load wear and easy bridge jamming, and no emergency navigation means for failure, the application adopts a drive motor to drive a drive gear and a drive pin gear to be symmetrically meshed and transmitted along an arc-shaped track, replaces unilateral hydraulic oil cylinder thrust, cooperates with a buffer to absorb impact at the limit position, eliminates unilateral wear and track deformation, adopts a pre-buried hidden structure for a fixed base unit, and internally hides a drive motor, so that the hydraulic oil cylinder and pipeline are completely cancelled; a drive motor is provided with a manual input interface for providing a failure emergency opening and closing means. The application is suitable for water village narrow river, ancient building style management and control area and periodic ship navigation scene.

Description

Technical Field

[0001] This invention belongs to the technical field of complete electromechanical systems for openable pedestrian bridges, and is particularly suitable for complete systems of large-angle single-support horizontal turning pedestrian bridges located in narrow waterways in water towns, near ancient building style control areas, and where regular centralized navigation of folk boats is required. Background Technology

[0002] A single-support horizontal rotating pedestrian bridge is an operable bridge designed to meet the navigation needs of narrow waterways in water towns. The bridge body rotates horizontally around a single support point to switch between waterway navigation and pedestrian walkways on both banks. Existing single-support horizontal rotating pedestrian bridges generally adopt a hydraulic drive scheme. Chinese patent document CN113322776A discloses a single-sided double hydraulic cylinder drive device for a horizontally rotating operable bridge. This device is suitable for a double cantilever movable span horizontally rotating operable bridge. It uses two hydraulic cylinders arranged diagonally on the same side of the pier base, and achieves synchronous drive through hydraulic oil circuit control. One end of the hydraulic cylinder push rod is hinged to the movable span of the bridge, and the other end of the cylinder is hinged to the pier base. The hydraulic cylinder push rod moves linearly to realize the rotational opening and closing of the movable span of the bridge. While this solution improves the force distribution of single-cylinder drive by arranging dual hydraulic cylinders diagonally, it still has the following drawbacks: the entire hydraulic cylinder system is over 13 meters long, weighs approximately 4 tons, and has a diameter of over 400 millimeters. The narrow waterways and land routes in the water town make it impossible for large cranes and lifting equipment to be brought in for disassembly and assembly; the exposed hydraulic station and cylinders disrupt the overall landscape of the ancient buildings along the riverbanks, failing to meet the requirements for scenic area management; and there is a risk of oil leakage from the cylinders and pipelines. Since the waterways in the water town are mostly shallow, brackish waterways, oil pollution could damage the original ecology of the water town and pollute the dragon boat parade route. The road does not meet the environmental protection control requirements for cultural tourism water towns; the hydraulic seals age quickly in high humidity and high salt spray environments, and the high frequency of equipment maintenance continuously interferes with residents' daily lives and folk boat activities; the continuous lateral thrust applied by the single-sided hydraulic cylinder causes unilateral wear and deformation of the arc track and bottom rollers, resulting in jamming and misalignment during the rotation process, which can easily cause the bridge to get stuck during the passage of the dragon boat formation; the large sweeping area of ​​the hydraulic cylinder affects the layout of the bridge pile foundation, and the large-size hydraulic cylinder placed at the bottom of the bridge body poses a risk of being submerged during tides and being hit by ships.

[0003] Chinese patent document CN107022950A discloses a gear and rack drive device for opening bridges. This device is suitable for single-span or double-span vertical rotating opening bridges. It uses an electric motor to drive the driving gear, driven gear, and rack through a reduction gearbox to achieve the opening and closing of the bridge. Gear and rack transmission has the advantages of simple structure and high transmission efficiency. However, this solution is suitable for vertical rotating opening bridges but not horizontal rotating opening bridges. Its gear and rack drive the bridge body to rotate in a straight line, which cannot be applied to the arc-shaped rotation of horizontal rotating pedestrian bridges. The device does not have an arc track and a buffer limit mechanism, so it cannot solve the problem of rigid impact of the bridge body at the extreme position during horizontal rotation. The drive unit of the device is exposed in the bridge structure, which cannot meet the requirement of the ancient building style control that the equipment should not be exposed. The device is not equipped with emergency opening and closing means, so the navigation channel cannot be opened after the equipment is damaged or the mains power is cut off. Summary of the Invention

[0004] This invention provides a single-support motor pin-driven horizontal rotary pedestrian bridge system, which solves the problems of existing single-support horizontal rotary pedestrian bridges that generally use hydraulic drive schemes, such as oil leakage polluting the river, exposed equipment damaging the appearance of ancient buildings, unilateral load causing uneven wear of the curved track and bottom rollers leading to bridge jamming, excessive sweeping area of ​​hydraulic cylinder affecting pile foundation layout and facing the risk of flooding and impact when externally placed, and lack of emergency navigation means in case of failure.

[0005] To achieve these and other advantages according to the present invention, a single-pivot motor pin-driven horizontal rotary pedestrian bridge system is provided, comprising:

[0006] A fixed base unit is installed on the riverbank;

[0007] The rotary bridge unit is installed on the fixed base unit in a single-support horizontal rotation manner, and can rotate horizontally between the closed position and the open position around the vertical rotation axis.

[0008] A motor pin drive unit includes a drive motor, a drive gear, a drive pin, an arc-shaped track, and an elastic buffer. The drive motor drives the drive gear to mesh with the drive pin, transmitting driving force along the arc-shaped track. The elastic buffer is positioned at the extreme position of the arc-shaped track to absorb rotational impact. The drive gear and the drive pin are arranged along the arc-shaped track, and the meshing force is transmitted along the tangential direction of the arc-shaped track.

[0009] The meshing transmission between the drive gear and the drive pin adopts a continuous multi-point meshing method. At any angle position from 0 degrees to 60 degrees of bridge rotation, the drive gear and the drive pin always maintain at least two meshing points in contact at the same time.

[0010] When the drive motor starts, it adopts a progressive torque output strategy, gradually increasing the output torque from a standstill to the rated value. The meshing force between the drive gear and the drive pin is gradually established along the tangential direction of the arc track. When the bridge body rotates to near the limit position of the arc track, the drive motor performs segmented deceleration. The rotation speed of the bridge body gradually decreases as it approaches the limit position, and it contacts the elastic buffer at a low speed. The elastic buffer provides elastic buffering at the limit position of the arc track, absorbing the residual kinetic energy of the bridge body and achieving a precise stop without impact.

[0011] Preferably, the fixed base unit includes a concrete rotating bearing, a bridge body connecting embedded part, a bridge body connecting embedded part, an H-beam, a protective casing, and drainage holes; the concrete rotating bearing supports the rotation of the bridge body, the bridge body connecting embedded part and the bridge body connecting embedded part achieve a pre-embedded hidden connection between the bridge body and the base, the H-beam serves as a pile foundation support, the protective casing provides protection and shielding for the H-beam, and the drainage holes drain water accumulated inside the base; the rotating bridge body unit integrates the drive motor into the equipment compartment at the rear of the bridge body, all drive equipment is built-in and hidden, without hydraulic cylinders and pipelines; the concrete rotating bearing and the bridge body connecting embedded part form a closed rotating bearing structure, and the bearing platform surface of the concrete rotating bearing and the pre-embedded connection surface of the bridge body connecting embedded part adopt a sealed contact design to prevent surface water from seeping into the base along the rotating bearing surface; the bridge body connecting embedded part and the bridge body connecting embedded part are both pre-embedded hidden connection structures, with the connection nodes embedded inside the concrete and not exposed on the bridge body surface.

[0012] Preferably, the tail of the drive motor has a standardized manual input interface, which is independent of the transmission link of the drive gear. When the drive motor is working normally, the manual input interface is in a disengaged state. When the mains power is interrupted or the drive motor fails, the maintenance personnel can directly drive the drive gear to rotate through the manual input interface. The drive gear meshes with the drive pin, and the bridge body rotates along the arc-shaped track to the navigation station. During manual operation, the rotation speed of the bridge body is controlled by the operator. When approaching the limit position of the arc-shaped track, the elastic buffer still provides elastic buffering to ensure that the bridge body can achieve a precise stop at the limit position without impact during manual opening and closing.

[0013] Preferably, the drainage holes are located in the lower part of the fixed base unit, using gravity to drain rainwater or seepage water accumulated inside the base, keeping the base dry and preventing corrosion of the concrete rotating support and the H-beam in a humid environment; the protective sleeve provides protection and shielding for the H-beam, achieving physical isolation between the H-beam and the external environment, while also shielding the exposed steel structure of the H-beam, meeting the visual requirement of ancient building style control that equipment should not be exposed.

[0014] Preferably, the progressive torque output strategy of the drive motor and the segmented deceleration operation constitute a complete start-stop operation sequence control logic; during the start-up phase, the drive motor is gradually loaded to the rated torque from a stationary state in a torque-increasing manner, and the meshing force of the drive gear and the drive pin is gradually established along the tangential direction of the arc-shaped track, so that the bridge body smoothly transitions from a stationary state to a uniform rotation state, avoiding the local stress concentration on the tooth surface of the drive pin caused by the gear meshing impact at the moment of start-up; during the uniform speed operation phase, the drive motor maintains a constant output torque, and the drive gear and the drive pin continue to mesh stably along the arc-shaped track, so that the bridge body runs smoothly at a set rotation speed; During the deceleration and stopping phase, when the bridge body rotates to near the limit position of the arc-shaped track, the drive motor performs segmented deceleration. The rotation speed of the bridge body gradually decreases as it approaches the limit position, and it contacts the elastic buffer at low speed. The elastic buffer provides elastic cushioning at the limit position of the arc-shaped track, absorbs the residual kinetic energy of the bridge body, and eliminates the rigid impact between the steel structure and the transmission components. Combined with the segmented deceleration, the bridge body achieves a precise and impact-free stop at the limit position. The starting phase and the deceleration and stopping phase are smoothly connected by a uniform speed operation phase. The three phases constitute a complete opening and closing operation sequence, ensuring that the transmission components of the bridge body wear evenly, the track does not deform, and the stopping position does not deviate under high-frequency opening and closing conditions throughout the year.

[0015] Preferably, the H-beam serves as a pile foundation support, connected to the concrete rotating bearing via a pile cap, thereby achieving a step-by-step transfer of bridge load to the deep foundation. The pile foundation arrangement of the H-beam does not spatially interfere with the rotation path of the arc-shaped track, and the driving path conforms to the bridge's rotation trajectory, avoiding the large-area sweeping and occupation of pile foundation space by traditional hydraulic cylinders. The concrete rotating bearing is connected to the bridge body via the pile cap.

[0016] Preferably, the output shaft of the drive motor is equipped with an electromagnetic brake, and a clutch mechanism is provided between the standardized manual input interface of the drive motor and the drive gear. When the drive motor is working normally, the clutch mechanism is in a disengaged state, the manual input interface is disconnected from the transmission link of the drive gear, and the electromagnetic brake is controlled according to the normal operating logic, without affecting the operating efficiency of the drive motor driving the drive gear. When the mains power is interrupted or the drive motor fails, the clutch mechanism switches to an engaged state, the manual input interface is connected to the transmission link of the drive gear, and the electromagnetic brake is de-energized and released, allowing the drive motor rotor to rotate freely. The maintenance personnel can directly drive the drive gear to rotate through the manual input interface. The drive gear meshes with the drive pin, and the bridge body rotates along the arc-shaped track. During manual operation, the rotation speed of the bridge body is controlled by the operator. When approaching the limit position of the arc-shaped track, the elastic buffer still provides elastic buffering to ensure that the bridge body achieves impact-free and precise stopping at the limit position during manual opening and closing.

[0017] Preferably, the drive motor is built into the tail section of the rotary bridge unit, and its installation position is located in a closed cavity on one side of the rotation center of the bridge body, completely isolated from the external environment. The operating noise of the equipment is less than 40 decibels, which meets the requirements of a quiet environment in the water town residential area. The drive motor drives the drive gear through a reducer. The reducer is integrated with the drive motor or externally installed at the output end of the drive motor. The drive gear meshes with the drive pin of the fixed section of the bridge body, causing the bridge body to rotate along the rotation center.

[0018] Preferably, it also includes:

[0019] A dual-position mechanical locking unit, comprising a closed passage lock assembly and a fully open passage lock assembly;

[0020] The closed passage lock assembly is installed at the end of the walkway on the opposite bank of the river. After the rotating bridge unit rotates to the 0° closed position, the locking tongue of the closed passage lock assembly is inserted laterally into the corresponding base lock hole to eliminate the pedestrian gap between the bridge and the walkway.

[0021] The bolt strength of the fully open navigation lock assembly is higher than that of the closed passage lock assembly. After the slewing bridge unit rotates to the 60-degree opening position, the bolt of the fully open navigation lock assembly is inserted into the locking base set on the shore support to resist the wind load and pedestrian load on the bridge body in the long-term open state and keep the bridge body from shaking and slipping throughout the entire process.

[0022] Both the closed access lock assembly and the fully open access lock assembly are equipped with alignment sensors. When the slewing bridge unit is in a stationary state and the alignment sensor detects that the bridge body is not fully aligned at the 0-degree closed position or the 60-degree open position, the motor pin drive unit is forcibly locked and prohibited from starting the slewing.

[0023] Preferably, the main beam of the rotating bridge unit is welded from high-strength structural steel, and a pre-arch is set at the far end of the rotating bridge to offset the effects of deflection and temperature changes during bridge rotation on the opening and closing of the bridge, ensuring that the bridge can open and close smoothly; the closed cavity at the tail of the bridge is filled with counterweight concrete to improve the stability of the bridge along the center of rotation; the pre-embedded parts connecting the bridge body in the fixed base unit cooperate with the pre-embedded parts connecting the bridge body to realize the connection between the rotating support of the bridge body and the bridge body through the pier; the bridge body can rotate horizontally in one direction from 0 degrees to 60 degrees, the 0-degree position closes and connects the pedestrian walkways on both banks for residents' daily walking, and the 60-degree position fully opens the river channel parallel to the bank for continuous passage of folk boat convoys.

[0024] The present invention has at least the following beneficial effects:

[0025] 1. This invention replaces traditional hydraulic drive with motor-driven pinion gears, completely eliminating hydraulic cylinders and pipelines, thus eliminating the risk of oil leakage polluting the waterways of the river and protecting the ecological environment of the dragon boat parade route. By embedding the drive motor and all drive equipment within the equipment compartment at the stern of the bridge, exposed equipment is avoided from damaging the overall landscape of the ancient buildings, meeting the requirements for the control of the ancient building style. Through the arrangement of drive gears and drive pinions along an arc-shaped track and the transmission of meshing force along the tangential direction, combined with a continuous multi-point meshing method, at least two meshing points are always in contact at any angle. It eliminates the one-sided wear and deformation of the arc track caused by the continuous lateral thrust applied by the traditional single-sided hydraulic cylinder, and avoids the risks of bridge jamming, misalignment, and high-frequency opening and closing conditions during bridge rotation. By combining a progressive torque output strategy with segmented deceleration, it avoids local stress concentration on the tooth surface caused by gear meshing impact during the starting phase, and uses an elastic buffer to absorb residual kinetic energy during the deceleration phase to achieve impact-free and precise stopping. This ensures that the transmission components of the bridge wear evenly, the track does not deform, and the stopping position does not deviate under high-frequency opening and closing conditions throughout the year, greatly extending the overall service life of the equipment.

[0026] 2. This invention utilizes a concealed connection structure within the fixed base unit, where the bridge body's embedded components connect to the bridge body's connecting embedded components. This allows all connection nodes between the bridge body and the base to be embedded within the concrete, not exposed on the bridge surface. This integrates the rotating bearing structure with the external landscape, meeting the visual requirement of concealed equipment in ancient building style management. The concrete rotating bearing and the bridge body's connecting embedded components form a closed rotating bearing structure. Furthermore, the sealed contact design between the bearing platform and the embedded connection surface prevents surface water from seeping into the base along the rotating bearing surface. Combined with drainage holes to drain internal water, this effectively prevents corrosion of the concrete rotating bearing and H-beams in humid environments, extending the base's service life. By embedding the drive motor and all drive equipment within the equipment compartment at the rear of the bridge body, with no exposed hydraulic cylinders or pipelines, the risk of large hydraulic cylinders being submerged during tides and impacted by ships is avoided.

[0027] 3. This invention features a standardized manual input interface pre-installed at the tail of the drive motor. This interface is independent of the transmission link of the drive gear. During normal operation, the manual interface is disengaged and does not affect the motor's drive efficiency. In the event of a mains power outage or drive motor failure, maintenance personnel can directly drive the drive gear to rotate through the manual input interface. The drive gear meshes with the drive pin, causing the bridge body to rotate along the arc track to the navigation position. This solves the problem of traditional hydraulic drive solutions lacking backup actuators and unable to open the navigation channel after equipment damage or mains power failure, ensuring that the navigation activities of folk vessels are not affected by sudden failures. During manual operation, the elastic buffer still provides elastic cushioning at the extreme position, ensuring that the bridge body can stop accurately without impact during manual opening and closing, avoiding rigid collision damage during manual operation.

[0028] 4. This invention uses drainage holes located in the low-level area of ​​the fixed base unit to automatically drain rainwater or seepage water accumulated inside the base using gravity, without the need for external power. This keeps the base dry and prevents corrosion of the concrete rotating bearing and H-beams in the high-humidity, high-salt-spray environment of the brackish water system, extending the service life of the equipment and reducing the interference of frequent maintenance on residents' daily lives and folk boat activities. The protective casing provides protection for the H-beams, achieving physical isolation between the H-beams and the external environment. At the same time, it covers the exposed surface of the H-beam structure, making the pile foundation structure harmonious and unified with the surrounding ancient building style, meeting the overall visual requirements for the protection of traditional style in the development of water town cultural tourism.

[0029] 5. This invention establishes a complete start-stop operation sequence control logic through a progressive torque output strategy of the drive motor, uniform speed operation, and segmented deceleration operation. The three operation stages are smoothly connected. In the start-up stage, torque is gradually applied to avoid local stress concentration on the tooth surface caused by gear meshing impact. In the uniform speed stage, a constant output torque is maintained to ensure the smooth operation of the bridge. In the deceleration stage, an elastic buffer is used to eliminate rigid impact between the steel structure and the transmission components, forming a complete flexible start-stop closed-loop control. This ensures that the transmission components wear evenly, the track does not deform, and the stopping position does not deviate under high-frequency start-stop conditions throughout the year. It solves the technical problem of increased track wear and decreased positioning accuracy caused by unilateral impact load in traditional hydraulic drive solutions, and reduces equipment maintenance frequency and operation and maintenance costs.

[0030] 6. This invention uses H-beams as pile foundation supports and connects them to concrete rotating bearings via pier caps, achieving a step-by-step transfer of bridge loads to the deep foundation. It is suitable for soft soil foundations in shallow water areas, with minimal pile foundation work and reduced damage to the original landforms of riverbanks and tidal flats. The arrangement of the H-beam pile foundations does not cause spatial interference with the curved track rotation path, and the drive path conforms to the bridge's rotation trajectory, avoiding the complex stress problems caused by the large-area sweeping of traditional hydraulic cylinders occupying pile foundation space. The concrete rotating bearings are connected to the bridge body via pier caps, enabling unidirectional horizontal rotation of the bridge body from 0 degrees to 60 degrees. The 0-degree position closes and connects the pedestrian walkways on both banks for residents' daily walking, while the 60-degree position fully opens the river channel parallel to the banks for continuous passage of folk boat convoys, meeting the dual needs of residents' daily passage and the navigation of intangible cultural heritage boats.

[0031] 7. This invention incorporates a clutch mechanism between the standardized manual input interface of the drive motor and the drive gear. During normal operation, the clutch mechanism is disengaged, completely disconnecting the manual input interface from the drive gear's transmission link. This does not affect the efficiency of the drive motor driving the drive gear, ensuring no loss of transmission efficiency in motor-driven mode. When mains power is interrupted or the drive motor fails, the clutch mechanism switches to the engaged state, connecting the manual input interface to the drive gear's transmission link. Maintenance personnel can directly drive the drive gear to rotate via the manual input interface to open and close the bridge. The application of the clutch mechanism ensures that a manual emergency transmission link can be quickly and reliably established in emergency situations, guaranteeing efficient daily operation while also providing emergency navigation support capabilities in extreme circumstances.

[0032] 8. This invention integrates the drive motor into a closed cavity within the equipment compartment at the rear of the rotary bridge unit, completely isolating it from the external high humidity and high salt spray environment. The operating noise of the equipment is below 40 decibels, meeting the stringent requirements for a quiet environment in water town residential areas and cultural tourism core areas. This avoids the continuous interference of traditional hydraulic station operating noise (above 70 decibels) on residents' daily lives and cultural tourism experiences. The drive motor drives the drive gear via a reducer. The reducer is integrated with the drive motor or externally installed at the motor output end. The reduction ratio and installation method can be flexibly configured according to the bridge load requirements and equipment compartment space, adapting to pedestrian bridge engineering scenarios with different spans and load requirements, and improving the system's adaptability to different water town river conditions.

[0033] 9. This invention uses a dual-position mechanical locking unit to mechanically lock the 0-degree closed position and the 60-degree open position respectively. After the bridge body is fully aligned at 0 degrees, the locking tongue of the closed passage lock assembly is inserted laterally into the locking hole of the base to eliminate the pedestrian gap between the bridge body and the walkway, ensuring the stability and safety of residents in the water town when walking across, and eliminating the slight swaying of the bridge body under wind load and pedestrian load. After the bridge body is rotated to the 60-degree open position, the fully open navigation lock assembly uses a high-strength locking tongue to insert into the locking base on the support seat on the bank, resisting the wind load and pedestrian load on the bridge body in the long-term open state, keeping the bridge body from swaying and slipping throughout the entire process. To ensure the stability of the bridge during the continuous passage of the folk boat convoy and avoid collisions caused by accidental shaking or slippage of the bridge, both the closed passage lock assembly and the fully open navigation lock assembly are equipped with alignment sensors. When the slewing bridge unit is stationary and the sensor detects that the bridge is not fully aligned in the 0-degree closed position or the 60-degree open position, the motor pin drive unit is forcibly locked and prohibited from starting the slewing, forming a forced self-check safety mechanism before starting. This prevents collisions caused by the bridge not being in position before the boat passes or accidental starting operations in an unaligned state, thus constructing a complete dual-position safety locking protection system.

[0034] 10. This invention utilizes high-strength structural steel welded to form the main beam of the rotating bridge unit. A pre-arch is installed at the far end of the rotating bridge to counteract the effects of deflection and temperature changes during bridge rotation on the opening and closing of the bridge. This ensures smooth opening and closing of the bridge under different ambient temperatures and operating conditions, avoiding bridge jamming caused by deflection deformation. The bridge's tail end is filled with counterweight concrete to increase its weight, improving stability along the rotation center and reducing centrifugal sway during rotation. The bridge's rotating support is connected to the bridge via a pier through pre-embedded components. The bridge can rotate horizontally in one direction from 0 to 60 degrees. The 0-degree position closes and connects to the pedestrian walkways on both banks for daily pedestrian access, while the 60-degree position fully opens the river channel parallel to the banks for continuous passage of folk boat convoys. This simplified single-point unidirectional rotation achieves efficient switching between daily passage and navigation conditions.

[0035] 11. This invention, through the linkage control logic of the electromagnetic brake and the manual mode switch, automatically cuts off the brake power supply in manual emergency mode, causing it to lose power and release, allowing the drive motor rotor to rotate freely. This avoids the technical difficulty of simultaneously overcoming the motor excitation resistance and brake friction resistance during manual operation. Combined with the clutch mechanism, the manual input interface is reliably connected to the reducer input shaft. Maintenance personnel only need to overcome the internal mechanical friction resistance of the reducer and the inertial resistance of the bridge body to drive the bridge body to rotate. This enables single-person manual operation to complete the emergency opening and closing of the bridge body, significantly improving the operability of emergency navigation support and avoiding the predicament of traditional solutions where excessive manual operation force prevents opening.

[0036] Other advantages, objectives and features of the present invention will become apparent in part from the following description, and in part from those skilled in the art through study and practice of the invention. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the fixed base unit in the single-pivot motor pin-driven horizontal rotary pedestrian bridge system of the present invention.

[0038] Figure 2 This is a schematic diagram of the structure of the rotary bridge body unit in the single-pivot motor pin-tooth driven horizontal rotary pedestrian bridge system of the present invention;

[0039] Figure 3 This is a schematic diagram of the motor pin tooth drive unit in the single-pivot motor pin tooth drive horizontal rotary pedestrian bridge system of the present invention.

[0040] Reference numerals: 1: Fixed base unit; 100: Connecting bridge body embedded part; 110: Concrete rotating support; 120: Drainage hole; 130: Bridge body connecting embedded part; 140: H-beam; 150: Casing; 2: Rotating bridge body unit; 3: Motor pin drive unit; 300: Arc track; 310: Elastic buffer; 320: Drive pin; 330: Drive gear; 340: Drive motor. Detailed Implementation

[0041] The present invention will now be described in further detail so that those skilled in the art can implement it based on the description.

[0042] It should be noted that, unless otherwise specified, the experimental methods described in the following implementation plan are all conventional methods, and the reagents and materials described are all commercially available unless otherwise specified.

[0043] This invention provides a horizontal rotary pedestrian bridge system driven by a single-pivot motor pin tooth, comprising:

[0044] Fixed base unit 1 is installed on the bank of the river;

[0045] The rotary bridge unit 2 is installed on the fixed base unit 1 in a single-support horizontal rotation manner, and can rotate horizontally between the closed position and the open position around the vertical rotation axis.

[0046] The motor-driven pinion unit 3 includes a drive motor 340, a drive gear 330, a drive pin 320, an arc-shaped track 300, and an elastic buffer 310. The drive motor 340 drives the drive gear 330 to mesh with the drive pin 320, transmitting driving force along the arc-shaped track 300. The elastic buffer 310 is positioned at the extreme positions of the arc-shaped track 300 to absorb rotational impact. The drive gear 330 and the drive pin 320 are arranged along the arc-shaped track 300, and the meshing force is transmitted along the tangential direction of the arc-shaped track 300. The meshing transmission of the drive gear 330 and the drive pin 320 adopts a continuous multi-point meshing method, operating at any angle position from 0 degrees to 60 degrees of bridge rotation. The drive gear 330 and the drive pin 320 always maintain at least two meshing points in contact simultaneously. When the drive motor 340 starts, it adopts a progressive torque output strategy, gradually increasing the output torque from a stationary state to the rated value. The meshing force between the drive gear 330 and the drive pin 320 is gradually established along the tangential direction of the arc track 300. When the bridge body rotates to near the limit position of the arc track 300, the drive motor 340 performs segmented deceleration. The rotation speed of the bridge body gradually decreases as it approaches the limit position, and the low-speed contact with the elastic buffer 310 provides elastic buffering at the limit position of the arc track 300, absorbing the residual kinetic energy of the bridge body and achieving impact-free and precise stopping.

[0047] The spatial configuration of the entire system is as follows: Fixed base unit 1 is located on one bank of the river, with four H-beams 140 arranged in a rectangle and sunk into the bearing layer of the foundation. The top is connected to the concrete rotating support 110 via a pier. One end of the slewing bridge unit 2 is installed on the concrete rotating support 110 via a slewing bearing, while the other end cantileveres across the river. A closed equipment compartment is located at the rear of the bridge (near the rotation center), with two drive motors 340 symmetrically arranged inside the equipment compartment about the longitudinal centerline of the bridge. An arc-shaped track 300 is laid on the upper surface of the pier of fixed base unit 1, with its arc center coaxial with the rotation center of the bridge. The top surface of the track is in contact with the rollers and drive gears 330 at the bottom of the bridge. The drive gears 330 are mounted on the output shaft of a reducer and mesh with drive pins 320 fixed on the upper surface of the arc-shaped track 300. When the bridge rotates, the drive gears 330 roll along the arc-shaped track 300, converting the driving force into the horizontal rotational motion of the bridge. The far end of the bridge body is equipped with a stop plate corresponding to the elastic buffer 310 at the end of the arc track 300. When the bridge body rotates to the limit position of 0 degrees or 60 degrees, the stop plate contacts the elastic buffer 310 to complete the buffer stop.

[0048] At the 0-degree closed position, the far end of the bridge body overlaps with the end of the walkway on the opposite bank, and the latch of the closed passage lock component extends and locks. At the 60-degree open position, the far end of the bridge body rotates back to be parallel to the riverbank, and the latch of the fully open navigation lock component extends and locks. Under the unified scheduling of the electronic control unit, the entire system completes each opening and closing cycle according to the sequence of "self-check → unlock → start → accelerate → constant speed → deceleration → buffer stop → lock → status confirmation".

[0049] Specifically, the fixed base unit 1 includes a concrete rotating bearing 110, a bridge body connecting embedded part 100, a bridge body connecting embedded part 130, an H-beam 140, a protective casing 150, and a drainage hole 120. The concrete rotating bearing 110 supports the rotation of the bridge body. The bridge body connecting embedded part 100 and the bridge body connecting embedded part 130 achieve a hidden pre-embedded connection between the bridge body and the base. The H-beam 140 serves as a pile foundation support. The protective casing 150 provides protection and shielding for the H-beam 140. The drainage hole 120 drains water accumulated inside the base. The rotating bridge body unit 2 integrates the drive motor 340 into the equipment compartment at the rear of the bridge body. All drive equipment is built-in and hidden, without hydraulic cylinders or pipelines. The concrete rotating bearing 110 and the bridge body connecting embedded part 130 form a closed rotating load-bearing structure. The bearing platform surface of the concrete rotating bearing 110 and the embedded connection surface of the bridge body connecting embedded part 130 adopt a sealed contact design to prevent surface water from seeping into the base along the rotating bearing surface. Both the bridge body connecting embedded part 100 and the bridge body connecting embedded part 130 are embedded concealed connection structures, with the connection nodes embedded inside the concrete and not exposed on the bridge body surface.

[0050] A standardized manual input interface is reserved at the tail of the drive motor 340, which is independent of the transmission link of the drive gear 330. When the drive motor 340 is working normally, this manual input interface is disengaged. In the event of a power outage or failure of the drive motor 340, maintenance personnel can directly drive the drive gear 330 to rotate via this manual input interface. The drive gear 330 engages with the drive pin 320, and the bridge body rotates along the arc-shaped track 300 to the navigation position. During manual operation, the bridge body rotation speed is controlled by the operator. When approaching the limit position of the arc-shaped track 300, the elastic buffer 310 still provides elastic cushioning, ensuring that the bridge body achieves a precise, impact-free stop at the limit position during manual opening and closing.

[0051] Drainage holes 120 are located in the lower area of ​​the fixed base unit 1, using gravity to drain rainwater or seepage water accumulated inside the base, keeping the base dry and preventing corrosion of the concrete rotating support 110 and H-beam 140 in a humid environment. The casing 150 provides protection for the H-beam 140, achieving physical isolation between the H-beam 140 and the external environment, while also concealing the exposed steel structure of the H-beam 140, meeting the visual requirement of not exposing equipment in the ancient building style control.

[0052] The progressive torque output strategy of the drive motor 340 and the segmented deceleration operation constitute a complete start-stop operation sequence control logic. During the start-up phase, the drive motor 340 gradually increases its torque from a stationary state to its rated torque. The meshing force between the drive gear 330 and the drive pin 320 gradually builds up along the tangential direction of the arc-shaped track 300, allowing the bridge to smoothly transition from a stationary state to a uniform rotational state, avoiding localized stress concentration on the tooth surface of the drive pin 320 due to gear meshing impact at the moment of start-up. During the uniform speed operation phase, the drive motor 340 maintains a constant output torque, and the drive gear 330 and the drive pin 320 continuously and stably mesh and transmit power along the arc-shaped track 300, allowing the bridge to run smoothly at the set rotational speed. During the deceleration and stopping phase, when the bridge body rotates to near the extreme position of the curved track 300, the drive motor 340 performs segmented deceleration. The rotational speed of the bridge body gradually decreases as it approaches the extreme position, and the low-speed contact occurs with the elastic buffer 310. The elastic buffer 310 provides elastic cushioning at the extreme position of the curved track 300, absorbing the residual kinetic energy of the bridge body and eliminating rigid impact between the steel structure and the transmission components. Combined with the segmented deceleration, this allows the bridge body to achieve a precise and impact-free stop at the extreme position. The start-up phase and the deceleration and stopping phase are smoothly connected by a uniform speed operation phase. These three phases constitute a complete opening and closing sequence, ensuring uniform wear of the transmission components, no track deformation, and no deviation in the stopping position under high-frequency opening and closing conditions throughout the year.

[0053] The H-beam 140 serves as the pile foundation support, connected to the concrete rotating bearing 110 via a pile cap, enabling the gradual transfer of bridge loads to the deeper foundation. The arrangement of the H-beam 140 piles does not spatially interfere with the rotation path of the curved track 300, and the drive path closely follows the bridge's rotation trajectory, avoiding the large-area sweeping and space occupation of traditional hydraulic cylinders. The concrete rotating bearing 110 is connected to the bridge structure via the pile cap.

[0054] A clutch mechanism is provided between the standardized manual input interface of the drive motor 340 and the drive gear 330. When the drive motor 340 is operating normally, this clutch mechanism is disengaged, and the manual input interface is disconnected from the transmission link of the drive gear 330, thus not affecting the operating efficiency of the drive motor 340 driving the drive gear 330. When the mains power is interrupted or the drive motor 340 fails, the clutch mechanism switches to the engaged state, and the manual input interface connects to the transmission link of the drive gear 330. Maintenance personnel can directly drive the drive gear 330 to rotate through the manual input interface. The drive gear 330 meshes with the drive pin 320, and the bridge body rotates along the arc-shaped track 300. During manual operation, the rotation speed of the bridge body is controlled by the operator. When approaching the limit position of the arc-shaped track 300, the elastic buffer 310 still provides elastic cushioning, ensuring that the bridge body achieves a precise and impact-free stop at the limit position during manual opening and closing.

[0055] The drive motor 340 is built into the equipment compartment at the rear of the rotary bridge unit 2. Its installation position is within a closed cavity on one side of the bridge's rotation center, completely isolated from the external environment. The operating noise of the equipment does not exceed 40dB, meeting the quiet environment requirements of the water town residential area. The drive motor 340 drives the drive gear 330 through a reducer. The reducer is integrated with the drive motor 340 or externally installed at the output end of the drive motor 340. The drive gear 330 meshes with the drive pin 320 of the fixed bridge section, causing the bridge to rotate around the rotation center.

[0056] The dual-position mechanical locking unit includes a closed access lock assembly and a fully open navigation lock assembly. The closed access lock assembly is installed at the end of the walkway on the opposite bank of the river. After the rotating bridge unit 2 rotates to the 0-degree closed position, the latch of the closed access lock assembly is inserted laterally into the corresponding base lock hole, eliminating the pedestrian gap between the bridge and the walkway. The latch of the fully open navigation lock assembly is stronger than that of the closed access lock assembly. After the rotating bridge unit 2 rotates to the 60-degree open position, the latch of the fully open navigation lock assembly is inserted into the locking base set on the bank support, resisting the wind load and pedestrian load on the bridge in the long-term open state, keeping the bridge stable and free from swaying and slippage throughout the entire process. Both the closed access lock assembly and the fully open navigation lock assembly are equipped with alignment sensors. When the rotating bridge unit 2 is stationary and the alignment sensor detects that the bridge is not fully aligned in the 0-degree closed position or the 60-degree open position, the motor pin drive unit 3 is forcibly locked, preventing the rotation from starting.

[0057] The main beam of the rotating bridge unit 2 is welded from high-strength structural steel. A pre-arch is set at the far end of the rotating bridge to counteract the effects of deflection and temperature changes during bridge rotation on the opening and closing of the bridge, ensuring smooth opening and closing. The closed cavity at the rear of the bridge is filled with counterweight concrete to improve the stability of the bridge along the rotation center. The bridge body embedded parts 100 and 130 in the fixed base unit 1 cooperate to realize the connection between the bridge body rotating support and the bridge body through the pier. The bridge body can rotate horizontally in one direction from 0 degrees to 60 degrees. The 0-degree position closes and connects the pedestrian walkways on both banks for residents' daily walking, while the 60-degree position opens the river channel parallel to the banks for continuous passage of folk boat convoys.

[0058] In a specific embodiment, the fixed base unit 1 is located on the riverbank and is used to bear and support the entire slewing bridge unit 2. The fixed base unit 1 includes a concrete slewing bearing 110, a bridge body connecting embedded part 100, a bridge body connecting embedded part 130, an H-beam 140, a protective casing 150, and a drainage hole 120.

[0059] The pile foundation consists of four H-beams (140mm, 610mm x 305mm x 149kg / m) of European standard wide-flange H-beams made of S355J2 low-alloy high-strength structural steel. These beams serve as pile supports extending deep into the riverbed bearing layer. The four H-beams are arranged in a rectangular pattern, with a spacing of 4.0m x 4.0m. The center-to-center distance between adjacent H-beams is 2.8m. The pile top elevation is +2.5m, the pile bottom elevation is -25.0m, and the pile length is 27.5m. The piles are driven to the design elevation using a vibratory hammer. After the pile top is cut to the design elevation, a 20mm thick Q345B steel end plate is installed. The end plate is connected to the flanges and web of the H-beams (140mm, 12mm, 610mm x 305mm), using double-sided fillet welds. A pier reinforcement cage is installed on the end plate. The pier reinforcement cage is made of HRB400 grade steel bars. The pier dimensions are 5.0m×5.0m×1.5m. The pier concrete strength grade is C40. The pier and the concrete rotating support 110 are integrally cast and connected.

[0060] The top of the 140mm H-beam piles is connected to the concrete rotating bearing 110 via a pile cap, enabling the gradual transfer of bridge loads to the deep foundation. Bearing capacity calculations were performed according to the "Code for Design of Building Pile Foundations" (JGJ 94-2008). The characteristic value of the vertical compressive bearing capacity of a single pile is 2850kN, which is greater than the maximum vertical load of 2200kN transferred by the superstructure, with a safety factor of 1.30. The characteristic value of the horizontal bearing capacity of a single pile is 162kN, which is greater than the maximum horizontal load of 85kN transferred by the superstructure, with a safety factor of 1.90, meeting the bearing requirements of the soft, shallow foundation in the water town. The casing 150 is made of 12mm thick Q235B steel plate with a diameter of 720mm. It is set around the H-beam 140. The top of the casing 150 is 500mm above the normal water level. It provides protection and shielding for the H-beam 140, realizing the physical isolation between the H-beam 140 and the external environment. At the same time, it shields the exposed steel structure of the H-beam 140, meeting the visual requirement of the ancient building style control that the equipment should not be exposed.

[0061] The concrete rotating bearing 110 is cast in situ using C50 high-performance concrete, with a strength grade no lower than C50 and a permeability grade no lower than P8. A sealed contact design is adopted between the bearing platform surface of the concrete rotating bearing 110 and the embedded connection surface of the bridge body connecting embedded part 130. A 5mm thick neoprene rubber sealing strip is laid on the bearing platform surface to prevent surface water from seeping into the base along the rotating bearing surface. Both the bridge body connecting embedded part 100 and the bridge body connecting embedded part 130 are made of Q345B low-alloy high-strength structural steel, with hot-dip galvanized anti-corrosion treatment and a zinc layer thickness of no less than 85μm. The bridge body connecting embedded part 100 is embedded inside the concrete rotating bearing 110, and the bridge body connecting embedded part 130 is embedded at the bottom of the rotating bearing of the rotating bridge unit 2. The two are connected by high-strength bolt pairs to achieve a concealed connection between the bridge body and the base. All connection nodes are embedded inside the concrete and are not exposed on the bridge body surface.

[0062] The drainage hole 120 is a PVC embedded pipe with a diameter of 50mm, which is arranged in the low area of ​​the foundation of the fixed base unit 1. The inlet of the drainage hole 120 is set at the lowest point of the foundation surface, and the outlet leads to the side wall of the river channel. It uses gravity to automatically discharge the rainwater or seepage water accumulated inside the base, keep the base dry, and prevent the concrete rotating support 110 and H-beam 140 from corroding in a high humidity and high salt spray environment.

[0063] This invention has been successfully implemented in a project. The bridge spans a narrow waterway in a water town, with a waterway width of 12m and a total bridge length of 18m. During the project, four 610mm H-beams were driven to the design elevation of -25.0m using 140mm piles. Static load tests on site verified that the characteristic value of the vertical compressive bearing capacity of a single pile was 2800kN, and the characteristic value of the horizontal bearing capacity of a single pile was 150kN. After the installation of the slewing bridge unit 2, 50 unloaded full-stroke slewing tests and 20 simulated crowd load full-stroke slewing tests were conducted. The results showed that the bridge's single opening and closing time was 600s under unload conditions and 620s under simulated crowd load conditions. The transitions between each operational stage were smooth, and the elastic buffer 310 effectively absorbed the residual kinetic energy of the bridge at its extreme positions. The stopping accuracy reached ±5mm, and there was no rigid impact phenomenon. Since its commissioning, the project has operated safely for over 36 months, with over 200 opening and closing operations, during which time no bridge jamming, stopping deviation, or equipment failure occurred.

[0064] For structural safety verification, a global finite element model of the slewing bridge element 2 was established using ANSYS finite element analysis software. The model used Solid185 solid elements to simulate the main beam structure, Contact174 contact elements to simulate the contact behavior of the slewing bearing, and Combin14 spring elements to simulate pile-soil interaction. The analysis conditions included: Condition 1 was the normal service condition: the bridge structure was closed, bearing its own weight plus 5 kN / m. 2 Crowd load plus 0.5 kN / m railing load; Scenario 2 is extreme wind load: the bridge opens to 60 degrees, bearing its own weight plus 0.8 kN / m 2 Wind load. Analysis results show that under load condition one, the maximum combined stress of the main beam is 285 MPa, which is less than 41% of the yield strength of S690QL steel (690 MPa); under load condition two, the maximum combined stress of the main beam is 312 MPa, which is less than 45% of the yield strength. The maximum contact stress of the slewing bearing under the two load conditions is 520 MPa and 580 MPa, respectively, both less than the allowable contact stress of 850 MPa for 42CrMo alloy steel. The maximum displacement of the 140mm H-beam pile foundation under horizontal load is 8.5mm, meeting the relevant specifications' requirement that the horizontal displacement at the pile top should not exceed 10mm.

[0065] The rotating bridge unit 2 is installed on the fixed base unit 1 using a single-support horizontal rotation method, allowing it to rotate horizontally between a 0-degree closed position and a 60-degree open position around the vertical rotation axis. The bridge rotation angle is determined based on the geometric relationship between the navigable clearance and the bridge length. The river width is 12m, the total bridge length is 18m, and the bridge rotation center is located at the fixed base unit 1 on the bank. When the bridge rotates to 60 degrees, the horizontal distance from the far end of the bridge to the end of the opposite bank walkway is 18 × sin60 degrees = 15.6m, and the effective navigable width of the river is 15.6m, which is more than four times the maximum width of the folk dragon boat fleet (3.5m), meeting the requirements for continuous passage of the boat convoy. The main beam of the rotating bridge unit 2 is a box-section beam welded from S690QL high-strength structural steel. S690QL high-strength structural steel conforms to European standard EN 10025-6, with a yield strength of not less than 690MPa and a tensile strength of 760 to 930MPa. Its chemical composition contains no more than 0.2% carbon, 0.8% silicon, 1.7% manganese, 0.025% phosphorus, 0.005% sulfur, 1.5% chromium, 0.7% molybdenum, and 2.0% nickel. It possesses excellent low-temperature impact resistance and corrosion resistance. The main beam has a total length of 18m, a beam height of 1.2m, a flange width of 0.6m, and a web and flange thickness of 20mm. The main girder is composed of an upper flange plate, a lower flange plate, and two web plates welded together. The upper flange plate is connected to the web plate, and the lower flange plate is connected to the web plate using double-sided bevel full-penetration welds. The welding method is CO2 gas shielded welding, with a welding wire diameter of 1.2mm, a welding current of 220-280A, a welding voltage of 24-30V, and a welding speed of 30-40cm / min. After welding, the main girder undergoes overall stress-relieving annealing at 600℃ for 2 hours, followed by furnace cooling to 200℃ and then air cooling. Considering the impact of bridge deflection during rotation on the opening and closing of the bridge, and combining this with the effect of temperature changes on bridge deflection, a pre-camber is set at the far end of the rotating bridge. The pre-camber value is 1‰ of the span, i.e., 18mm. This is achieved by pre-setting an 18mm reverse camber on the main girder welding jig to ensure smooth opening and closing of the bridge under different ambient temperatures and operating conditions.

[0066] The enclosed cavity at the rear of the bridge is filled with counterweight concrete. The internal dimensions of the enclosed cavity are 2.4m × 1.6m × 1.0m, and the volume is 3.84m³. 3 The counterweight concrete uses C30 fine aggregate concrete, with a maximum aggregate size of no more than 10mm, a slump of 80 to 100mm, and a filling volume of 3.6m³. 3The total counterweight is approximately 8.6 tons. The counterweight concrete is poured in sections through a pouring hole at the top of the enclosed cavity, with each section not exceeding 300mm in height. It is compacted using an immersion vibrator at a frequency of 50Hz for 30 seconds. Each section is cured for 72 hours until its strength reaches at least 75% of the design strength before the next section is poured. After the final pour, the pouring hole at the top of the enclosed cavity is sealed with a 20mm thick Q345B steel plate with a weld leg height of 8mm. After the counterweight concrete is filled, the total weight at the tail of the bridge increases to 50.6 tons, and the center of gravity shifts approximately 0.8m towards the rotation center, effectively reducing centrifugal sway and far-end deflection during bridge rotation. The overturning safety factor is 1.62, meeting the requirement of an overturning safety factor of not less than 1.5. The bottom of the main beam of slewing bridge unit 2 is integrally machined with a wear-resistant annular base along the circumference of the slewing circle. The annular base is made of 42CrMo alloy steel, and the surface hardening reaches HRC45 to HRC50. The annular base is connected to the inner ring of the slewing bearing by high-strength bolts, and the outer ring of the slewing bearing is fixedly connected to the concrete rotating support 110 through the bridge body connecting embedded part 130. After the slewing bearing undergoes 10,000 cycles of reciprocating slewing life test under simulated working conditions, the increase in slewing bearing clearance is no more than 0.10 mm, and the increase in friction torque is no more than 15% of the initial value, meeting the requirement of a design service life of not less than 30 years.

[0067] Based on the above structural arrangement, the mechanical coordination mechanism between the bridge's deflection resistance and overturning resistance is as follows:

[0068] The coordination between the pre-arch and the track counter-arch: The bridge body has a pre-arched 18mm diameter when unloaded. When the bridge body deflects under pedestrian load, the pre-arch gradually counteracts the vertical displacement. Simultaneously, the curved track 300 provides a continuous upward supporting reaction force to the bridge body via bottom rollers. This reaction force increases with the load, working together with the pre-arch to control the vertical displacement of the far end of the bridge body within ±5mm. This ensures accurate alignment of the bridge body under any working condition, preventing height differences or jamming between the bridge body and the walkway ends due to excessive deflection.

[0069] The combination of counterweight and track lateral restraint: The tail counterweight shifts the overall center of gravity of the bridge approximately 0.8m towards the center of rotation, significantly reducing the overturning moment of the bridge around the center of rotation. Simultaneously, the curved track 300 provides lateral restraint reaction force to the bridge in the horizontal direction, resisting centrifugal swaying during the bridge's rotation. The combined effect of these two factors achieves an overturning safety factor of 1.62, ensuring that the bridge has no risk of overturning when subjected to wind loads at the 60-degree open position.

[0070] The aforementioned pre-arch, counterweight, and track support form a three-dimensional mechanical chain of "upper support (pre-arch) - middle movement (counterweight) - lower support (track counter-arch)," none of which can be omitted. Together, they ensure the structural stability and alignment accuracy of the bridge under high-frequency opening and closing conditions throughout the year.

[0071] The slewing bridge unit 2 integrates the drive motor 340 within the equipment compartment at the rear of the bridge. All drive equipment is internally concealed, with no hydraulic cylinders or pipelines. The equipment compartment at the rear of the bridge is a closed steel box structure with 10mm thick walls. The inner walls of the equipment compartment are lined with 30mm thick rock wool sound-absorbing panels. The access door to the equipment compartment uses a double-sealed structure, achieving an IP65 protection rating. The equipment compartment is installed within a closed cavity on one side of the bridge's rotation center, completely isolated from the external high-humidity, high-salt-spray environment.

[0072] The motor pin drive unit 3 includes a drive motor 340, a drive gear 330, a drive pin 320, an arc-shaped track 300, and an elastic buffer 310. There are two drive motors 340, each with a rated power of 22kW, for a total rated power of 44kW. Each motor has a rated speed of 1470 r / min and a rated torque of 143 N·m, for a total rated torque of 286 N·m. The frequency conversion speed range is 0 to 1500 r / min. The motor insulation class is F, and the protection class is IP55. The two drive motors 340 are symmetrically arranged in the equipment compartment at the rear of the rotary bridge unit 2, and are synchronously controlled by a Siemens S7-1500 series programmable logic controller (PLC) CPU1511-1 PN. Under no-load conditions, the speed synchronization error of the two drive motors 340 is no greater than ±0.5 r / min, corresponding to a bridge rotation angle error of no greater than ±0.02 degrees. Under full load conditions, the bridge can withstand 5 kN / m of torque. 2 Under crowd load conditions, the speed synchronization error is no greater than ±1.0 r / min, corresponding to a bridge body rotation angle error of no greater than ±0.05 degrees, ensuring that the two drive motors 340 can operate in coordination under any working condition, avoiding uneven load and jamming caused by asynchrony. When one drive motor 340 fails, the programmable logic controller automatically detects the fault and disconnects the faulty motor. The remaining drive motor 340 operates briefly at 150% of its rated torque: 214.5 N·m, continuously driving the bridge body to complete the current opening and closing cycle. In single-motor emergency drive mode, the bridge body rotation speed decreases from the normal 2.0° / s to 1.0 degree / s, and the single opening and closing time is extended to 1200s, but the bridge body can still smoothly complete the full stroke rotation from 0 degrees to 60 degrees and achieve precise stopping at the extreme positions. The output end of each drive motor 340 is connected to a helical gear reducer with a reduction ratio of 25.18, and the output torque of a single motor is 3600 N·m, with a total output torque of 7200 N·m for both motors. The reducer is integrated with the drive motor 340 and installed on the motor mounting base in the equipment compartment at the rear of the bridge. The motor mounting base is welded from Q345B steel plate, and a 10mm thick rubber vibration damping pad is installed between the base and the bottom plate of the equipment compartment.

[0073] There are two drive gears 330, each mounted on the output shaft of one of the two reducers. The two drive gears 330 are symmetrically arranged on both sides of the tail of the rotary bridge unit 2, symmetrically distributed relative to the longitudinal centerline of the bridge. Each drive gear 330 is an involute spur gear with a module of 16mm, 21 teeth, and a tooth width of 120mm. It is made of 42CrMo alloy steel, tempered to a hardness of HB280 to HB320, and the tooth surface is hardened by medium-frequency quenching to a hardness of HRC50 to HRC55. The drive pins 320 are evenly arranged along the arc-shaped track 300, with a pitch of 50mm between adjacent drive pins 320. There are 110 drive pins 320, distributed along the arc length of the track 300, covering a rotation range of 0 to 60 degrees. The drive pin 320 is made of 42CrMo alloy steel, tempered to a hardness of HB260 to HB300, and its tooth surface is high-frequency quenched to a hardness of HRC48 to HRC52. The drive pin 320 is fixed to the upper surface of the arc-shaped track 300 by welding. Each drive pin 320 is connected to the arc-shaped track 300 by a double-sided fillet weld with a weld leg height of 8mm. Two drive gears 330 simultaneously mesh with the drive pin 320. At any angle position where the bridge body rotates from 0 to 60 degrees, each drive gear 330 maintains 2 to 3 meshing points simultaneously with the drive pin 320, for a total of 4 to 6 meshing points simultaneously. This ensures continuous and stable transmission and avoids tooth surface wear or meshing failure due to excessive local stress during single-point meshing. During multi-point meshing, the transmission torque is evenly distributed to each contact tooth surface through multiple meshing points. The maximum load borne by a single point is reduced to 1 / 2 to 1 / 3 of that during single-point meshing, effectively avoiding pitting and scuffing failure of the tooth surface.

[0074] The curved track 300 is rolled from Q345B low-alloy high-strength structural steel, serving a dual function of rotation guidance and load-bearing support: it not only acts as the installation base for the drive pin 320 but also as a load-bearing track during bridge rotation, bearing the vertical load and overturning moment transmitted by the bridge body through the bottom rollers, providing stable rotational support reaction force for the bridge body, and effectively suppressing the rotational deflection at the far end of the bridge body. The curved track 300 has a radius of curvature of 2500mm, a track width of 200mm, a track height of 120mm, a track web thickness of 25mm, and a flange thickness of 30mm. The curved track 300 is laid on the upper surface of the platform of the fixed base unit 1. The rotation center of the curved track 300 is coaxially arranged with the rotation center of the bridge body. The arc length of the curved track 300 covers a rotation range of 0 degrees to 65 degrees, of which 0 degrees to 60 degrees is the normal rotation working range of the bridge body, and 60 degrees to 65 degrees is the deceleration and buffer stroke range. The curved track 300 is fixed to the bearing platform of the concrete rotating support 110 by anchor bolts. The anchor bolts are M30, made of Q345B, and buried at a depth of 400mm. One anchor bolt is arranged every 500mm along the arc length of the curved track 300.

[0075] The progressive torque output strategy of drive motor 340 is executed by the frequency converter according to a preset S-shaped acceleration curve. The frequency converter adopts Siemens G120 series frequency converter, with built-in V / F control and vector control modes. During the start-up phase, after receiving the start command from the programmable logic controller, the frequency converter controls the output torque of the two drive motors 340 to gradually increase synchronously from 0 to the rated torque of 143 N·m per motor (total 286 N·m) according to the S-shaped acceleration curve. The S-shaped acceleration curve is divided into three sub-stages: the first sub-stage is the initial acceleration stage, lasting for 2 seconds, with torque increasing at 0.5 N·m / s. 2 The acceleration increases from 0 to 20 N·m; the second sub-stage is the main acceleration phase, lasting 4 seconds, during which the torque increases from 20 N·m to 120 N·m at a rate of 30 N·m / s; the third sub-stage is the final acceleration phase, lasting 2 seconds, during which the torque increases at a rate of 5 N·m / s. 2 The acceleration increases from 120 N·m to the rated torque of 143 N·m. The entire gradual torque loading process lasts 8 seconds. The meshing force between the drive gear 330 and the drive pin 320 is gradually established along the tangential direction of the arc track 300. The bridge body smoothly transitions from a stationary state to a uniform rotation state, avoiding local stress concentration on the tooth surface of the drive pin 320 caused by the gear meshing impact at the moment of startup. During the uniform speed operation phase, the programmable logic controller controls the torque output of the two drive motors 340 to automatically adjust according to real-time load fluctuations. The torque output range of a single motor is 60 to 80 N·m, and the total output torque is maintained between 120 and 160 N·m. The drive gear 330 and the drive pin 320 continuously and stably mesh and transmit along the arc track 300, and the bridge body runs smoothly at the set rotation speed of 2.0 degrees / second.

[0076] The segmented deceleration strategy of the drive motor 340 is executed by the programmable logic controller (PLC) according to a preset multi-segment deceleration curve. When the bridge body rotates to 5 degrees before the extreme position of the curved track 300, the PLC sends a first-stage deceleration command to the frequency converter, reducing the output frequency of the drive motor 340 from 50Hz to 25Hz, and the bridge body rotation speed from 2.0 degrees / second to 1.0 degrees / second, lasting for 6 seconds. When the bridge body rotates to 2 degrees before the extreme position of the curved track 300, the PLC sends a second-stage deceleration command to the frequency converter, further reducing the output frequency of the drive motor 340 from 25Hz to 10Hz, and the bridge body rotation speed from 1.0 degrees / second to 0.4 degrees / second, lasting for 5 seconds. When the bridge body rotates to 0.5 degrees before the extreme position of the 300mm arc track, the programmable logic controller sends a third-stage deceleration command to the frequency converter. The output frequency of the drive motor 340 decreases from 10Hz to 3Hz, and the bridge body's rotation speed decreases from 0.4 degrees / second to 0.1 degrees / second for 5 seconds. The bridge body contacts the elastic buffer 310 at a low speed of 0.1 degrees / second. The entire segmented deceleration process lasts 16 seconds. The elastic buffer 310 absorbs the residual kinetic energy of the bridge body, and in conjunction with the segmented deceleration, enables the bridge body to achieve a precise, impact-free stop at the extreme position. The start-up phase and the deceleration and stopping phase are smoothly connected by a uniform speed operation phase. The three phases constitute a complete opening and closing sequence, ensuring uniform wear of the transmission components, no track deformation, and no deviation in the stopping position under high-frequency opening and closing conditions throughout the year.

[0077] Two elastic buffers 310 are installed, one at the 0-degree limit position and the other at the 60-degree limit position of the curved track 300. Each elastic buffer 310 includes a buffer mounting base, a polyurethane elastomer buffer block, and a buffer limiting baffle. The buffer mounting base is welded from Q345B steel plate and fixed to the end of the curved track 300 with four M24 high-strength bolts. The polyurethane elastomer buffer block is cylindrical, with a diameter of 120mm and a height of 150mm. The hardness of the polyurethane elastomer material is Shore A90, the maximum compressive deformation is 30mm, and the maximum energy absorption is 15kJ. The speed of the bridge body during the uniform running phase is 2.0 degrees / second, and the speed during the final phase of the segmented deceleration operation is 0.1 degrees / second. The total weight of the bridge is 50.6t (including counterweight), with a turning radius of 2.5m. The curved track has a radius of curvature of 300. The residual kinetic energy of the bridge in the final deceleration stage is approximately 2.4kJ. Each elastic buffer 310 has a maximum energy absorption of 15kJ, and the two elastic buffers 310 have a combined maximum energy absorption of 30kJ, which is 12.5 times the residual kinetic energy of the bridge, providing ample safety margin. The buffer limit baffle is located at the rear end of the polyurethane elastomer buffer block and is made of 20mm thick Q345B steel plate, welded to the buffer mounting base. When the bridge rotates to near the limit position of the curved track 300, the tail stop plate of the rotating bridge unit 2 first contacts the polyurethane elastomer buffer block. The polyurethane elastomer buffer block undergoes elastic compression deformation (the compression deformation is approximately 5mm when absorbing 2.4kJ of energy), converting the residual kinetic energy of the bridge into elastic potential energy, absorbing the residual kinetic energy of the bridge, eliminating the rigid impact between the steel structure and the transmission components, and achieving impact-free and precise stopping.

[0078] The drive motor 340 is built into the equipment compartment at the rear of the rotary bridge unit 2; all drive equipment is internally concealed. The enclosed cavity of the equipment compartment has internal dimensions of 3.0m × 2.5m × 2.0m, with a total footprint of approximately 7.5m². 2 This equipment compartment integrates and houses all supporting equipment, including the drive motor, reducer, frequency converter, programmable logic controller, and ventilation and heat dissipation system. The drive motor itself occupies approximately 2 square meters. 2 The remaining space is for the installation, operation, and heat dissipation of supporting equipment. The equipment compartment houses an electrical control cabinet, a Rittal TS 8 series cabinet with an IP54 protection rating. The cabinet contains electrical components such as frequency converters, programmable logic controllers, contactors, and circuit breakers. The equipment compartment also includes a ventilation and heat dissipation system comprising one axial exhaust fan and one axial intake fan, with the exhaust fan having an airflow of 3000 m³ / h. 3 / h, the intake fan air volume is 3000m³ / h. 3 The temperature inside the equipment compartment is maintained within the range of -10℃ to +40℃ per hour. Temperature and humidity sensors are installed inside the equipment compartment to monitor the internal environmental parameters in real time.

[0079] For the high humidity and high salt spray environment of the water town: the C5-M marine atmospheric corrosion rating in ISO 12944 standard, the anti-corrosion coating system for the outer surface of the main beam and bridge steel structure (S690QL high-strength steel) is as follows: the bottom layer is epoxy zinc-rich primer with a dry film thickness of 80μm and a zinc powder content of not less than 80%; the middle layer is epoxy micaceous iron oxide intermediate paint with a dry film thickness of 100μm; the top layer is polyurethane topcoat with a dry film thickness of 80μm; the total dry film thickness is not less than 260μm, meeting the durability requirements of more than 15 years in the ISO 12944 C5-M corrosive environment. The corrosion protection treatment for key transmission components such as drive gear 330, drive pin 320, and arc track 300 is as follows: the base material is 42CrMo alloy steel, which is quenched and tempered before nitriding (nitriding layer depth 0.3 to 0.5 mm, surface hardness HV800 to HV1000), followed by Dacromet coating (coating thickness 8 to 12 μm), with a neutral salt spray test tolerance time of not less than 1000 hours. Fasteners (high-strength bolts, anchor bolts, etc.) are treated with zinc-nickel alloy electroplating, with a plating thickness of 8 to 12 μm, combined with passivation treatment, and have a neutral salt spray test tolerance time of not less than 1000 hours. Neutral salt spray (NSS) tests were conducted according to GB / T 10125-2021 standard. After 2000 hours of testing, the coating surface of the S690QL high-strength steel test plate showed no blistering, peeling, or red rust, and the pull-off adhesion was 6.5 MPa (not less than 80% of the original value of 8.0 MPa). The surface of the 42CrMo alloy steel test block showed no red rust or pitting. The surface of the high-strength bolt test specimen showed no red rust. Pin-gear pair wear tests were conducted according to GB / T 12444-2006 standard. The tests were performed on an MMW-1A vertical universal friction and wear testing machine. The test specimens were annular specimens made of the same material and heat treatment process as the actual drive gear 330 and drive pin 320. The test conditions were: load 500 N, rotation speed 200 r / min, lubrication method of periodically applying MoS2 lithium-based grease (applied once every 100 opening and closing cycles), ambient temperature 25±5℃, and relative humidity 60±10%. After the test was conducted to the equivalent of 5000 opening and closing cycles of sliding distance, the average wear depth of the drive gear 330 tooth surface was 0.08 mm, and the average wear depth of the drive pin tooth 320 tooth surface was 0.12 mm. Based on an average of 200 opening and closing cycles per year, the service life of both the drive gear 330 and the drive pin tooth 320 is no less than 25 years.

[0080] The drive motor 340 has a standardized manual input interface at its tail. This interface is a hexagonal shaft extension end with a side-to-side distance of 27mm and a shaft extension length of 40mm. The manual input interface connects to the input shaft of the reducer via a coupling. The coupling is a plum blossom-shaped flexible coupling made of cast steel with an internal polyurethane plum blossom-shaped elastomer. The manual input interface is independent of the transmission link of the drive gear 330. During normal operation, the manual input interface is in a disengaged state, meaning the hexagonal shaft extension end is not connected to any drive device. When the mains power is interrupted or the drive motor 340 fails, maintenance personnel can attach a portable hand-cranked drive device to the hexagonal shaft extension end. The portable hand-cranked drive device includes a hand crank and a speed increaser. The speed increaser is a planetary gear speed increaser with a speed ratio of 1:3, and the hand crank arm is 400mm long. The maintenance personnel turn the hand crank, which drives the manual input interface to rotate through the speed increaser, thereby driving the drive gear 330 to rotate. The drive gear 330 meshes with the drive pin 320 for transmission, and the bridge body rotates along the arc track 300 to the navigation station.

[0081] The output shaft of the drive motor 340 is equipped with an electromagnetic brake with a rated braking torque of 200 N·m and an operating voltage of 24V DC. The electromagnetic brake is linked to the drive motor 340 for control. During normal operation, the brake is released when energized, allowing the motor to rotate freely. When the machine stops or malfunctions, the brake is de-energized and engages, thus locking the motor shaft.

[0082] A clutch mechanism is provided between the standardized manual input interface of the drive motor 340 and the drive gear 330. The clutch mechanism is an electromagnetic clutch with a rated transmission torque of 400 N·m, a rated voltage of 24V DC, and a response time of no more than 0.3 s. The electromagnetic clutch is installed between the input shaft of the reducer and the manual input interface. The driving end of the electromagnetic clutch is connected to the manual input interface, and the driven end is connected to the input shaft of the reducer.

[0083] When the drive motor 340 is working normally, the electromagnetic clutch is in a de-energized disengaged state, the manual input interface is disconnected from the transmission link of the drive gear 330, and the electromagnetic brake is controlled according to the normal operating logic, which does not affect the operating efficiency of the drive motor 340 driving the drive gear 330.

[0084] In the event of a mains power outage or failure of drive motor 340, maintenance personnel can manually operate a switch. This switch sends a linkage control signal: on one hand, it energizes and engages the electromagnetic clutch, connecting the manual input interface to the transmission link of drive gear 330; on the other hand, it de-energizes and releases the electromagnetic brake, allowing the rotor of drive motor 340 to rotate freely. This eliminates the additional load of overcoming the electromagnetic resistance of the motor and the frictional resistance of the brake during manual operation. In this state, maintenance personnel can drive gear 330 to rotate via the manual input interface, only needing to overcome the internal mechanical frictional resistance of the reducer and the inertial resistance of the bridge body. This significantly reduces the manual burden, ensuring that a single person can complete the bridge rotation operation with reasonable physical exertion.

[0085] The dual-position mechanical locking unit includes a closed passage lock assembly and a fully open navigation lock assembly. The closed passage lock assembly is installed on the lock seat at the end of the walkway on the opposite bank of the river. It includes one set of electrically operated telescopic bolt locks with a bolt diameter of 30mm, a bolt travel of 80mm, a bolt material of 45# steel, and a surface hardened to a hardness of HRC40 to HRC45. The rated thrust is 10kN, the operating voltage is 24V DC, and the protection level is IP65. After the rotating bridge unit 2 rotates to the 0-degree closed position, the bolt of the closed passage lock assembly extends laterally by 80mm under electric drive and inserts into the corresponding base lock hole. The base lock hole is a steel pipe sleeve pre-embedded in the concrete at the end of the walkway. The steel pipe sleeve has an inner diameter of 35mm, a depth of 100mm, a wall thickness of 5mm, and is made of Q345B material. After the bolt is inserted into the lock hole, the pedestrian gap between the bridge and the walkway is eliminated. The locking force of the closed passage lock assembly is designed to be 10kN. The bridge body is subjected to a crowd load of 5kN / m² and a horizontal railing load of 0.5kN / m when it is in the 0-degree closed position. Under the most unfavorable working condition (eccentric arrangement of crowd load), the maximum shear force borne by the lock tongue does not exceed 8kN. The safety factor of the design locking force of 10kN is 1.25.

[0086] The fully open navigation lock assembly includes two sets of electrically operated telescopic bolt locks, symmetrically arranged on support seats on both sides of the shore. Each set of electrically operated telescopic bolt locks has a bolt diameter of 50mm, a bolt travel of 120mm, and a bolt material of 40Cr alloy steel, with a surface hardened to a hardness of HRC45 to HRC50. The rated thrust is 20kN, the operating voltage is 24V DC, and the protection rating is IP65. The bolt strength of the fully open navigation lock assembly is higher than that of the closed passage lock assembly. After the slewing bridge unit 2 rotates to the 60-degree open position, the bolt of the fully open navigation lock assembly extends laterally by 120mm under electric drive and inserts into the locking base set on the shore support seat. The locking base is a steel pipe sleeve pre-embedded in the concrete of the support seat, with an inner diameter of 55mm, a depth of 140mm, a wall thickness of 8mm, and a material of Q345B. After the locking tongue is inserted into the locking base, it resists the wind load and pedestrian load on the bridge body during long-term open operation, ensuring that the bridge body remains stable and does not sway or slip. The locking force design value of the fully open navigation lock assembly is 10kN, and the bridge body withstands wind load (basic wind pressure 0.8kN / m²) at a 60-degree open position. 2 The windward area is 18m × 1.2m = 21.6m. 2 The maximum shear force that the two sets of locking tongues can withstand is no more than 12kN, with each set of locking tongues bearing 6kN. The safety factor of the design locking force of 10kN is 1.67. The wind load is 17.3kN and the pedestrian load is 1.5kN (assuming the maintenance personnel are working at the far end of the bridge).

[0087] Both the closed access lock assembly and the fully open navigation lock assembly are equipped with alignment sensors. These sensors use inductive proximity switches with a detection distance of 8mm, an operating voltage of 10 to 30V DC, and an NPN normally open output. The alignment sensors are located at the bottom of the base lock hole and the locking base, respectively. When the bolt is fully inserted into the lock hole or the locking base to a predetermined depth, the alignment sensor detects the proximity signal of the metal bolt and outputs a positioning signal. When the slewing bridge unit 2 is stationary and the alignment sensor detects that the bridge body is not fully aligned at the 0-degree closed position or the 60-degree open position (i.e., the alignment sensor does not output a positioning signal), the programmable logic controller forcibly cuts off the power supply circuit of the drive motor 340 and activates the mechanical brake. The motor pin drive unit 3 is forcibly locked, preventing it from starting to rotate.

[0088] The electrical control system adopts a dual-redundancy architecture, including two independent programmable logic controllers (PLCs): Siemens S7-1500 series, CPU 1511-1 PN; two independent frequency converters: Siemens G120 series; and two independent power supply circuits. The mean time between failures (MTBF) of the dual-redundant electrical control system is approximately 3.8 × 10⁻⁶. 5 h (approximately 43 years), compared to a single electronic control system (MTBF approximately 4.5 × 10⁻⁶). 5h) Reliability is improved by approximately 45%, and within the MTBF range, the probability of a single point of failure is less than 0.1%. An emergency power system is installed next to fixed base unit 1, including one online UPS (30kVA capacity, lead-acid battery pack, 12V / 100Ah × 32 cells in series, total capacity 38400VAh) and one diesel generator set (rated power 50kW, fuel tank capacity 200L). The UPS can provide continuous power for 7.68 hours under full load (approximately 5kW standby power consumption of the electrical control system plus the 340 drive motor). Under full load (22kW operating power consumption of the 340 drive motor plus 3kW power consumption of the electrical control system equals 25kW), and based on a diesel consumption rate of 220g / kWh and a diesel density of 0.84kg / L, the diesel generator set can operate continuously for 200L × 0.84kg / L / (25kW × 0.22kg / kWh) = 30.5 hours. The integrated emergency power supply system has a total continuous power supply time of no less than 38 hours, which fully meets the emergency power supply needs for power outages during folk boat navigation activities.

[0089] The electrical control system is equipped with a remote monitoring platform communication interface, supporting data interaction with the upper-level monitoring platform via 4G / 5G wireless network. The communication protocol adopts Modbus TCP / IP, and the data transmission format conforms to the GB / T 19582-2008 standard. Data transmission security measures include: data transmission using TLS 1.2 encryption; firewall and IP whitelist filtering mechanisms on the communication interface, allowing only authorized IP addresses to access; monitoring data uploaded every 10 seconds, including key parameters such as real-time bridge angle, drive motor 340 operating status (current, torque, temperature), elastic buffer 310 status, and locking unit status; and system logs recording all operation commands and alarm information, with a retention period of no less than 180 days.

[0090] The electrical control system reserves standardized data interfaces, supporting seamless integration with the water town cultural tourism monitoring platform. The physical interface is an RJ45 Ethernet interface (1000BASE-T), the communication protocol is HTTP / HTTPS RESTful API, and the data format is JSON. Uploaded data includes the bridge's real-time status (0 degrees closed / running / 60 degrees open), current position angle (accuracy ±0.1 degrees), current operating mode (automatic / manual / emergency), drive motor 340 operating parameters (current, torque, temperature), fault alarm codes, and estimated completion time. Received commands include remote start / open, remote start / close, remote emergency stop, and system self-check. The interface response time is no greater than 2 seconds, and the data update frequency is once per second. The interface supports two-way authentication (digital certificate plus API key) to ensure that only authorized monitoring platforms can send control commands.

[0091] The quantitative comparison of this invention with traditional hydraulic drive solutions in several key indicators is as follows: energy consumption per opening and closing cycle is reduced from 12.0 kWh to 3.0 kWh, a reduction of 75%; annual maintenance hours are reduced from 48 hours to 16 hours, a reduction of 67%; equipment operating noise is reduced from over 70 dB to no more than 40 dB, a reduction of over 30 dB; and the equipment footprint is reduced from approximately 10 m² for the hydraulic station and exposed cylinders. 2 The entire footprint of the motor drive system is reduced to approximately 7.5m. 2 (Including the integrated equipment compartment), if only the drive motor body is considered, the floor space is approximately 2m². 2 The reduction is up to 80%; at the same time, it completely eliminates the external footprint of the hydraulic station and the space occupied by the oil cylinder sweeping, greatly freeing up the limited space under the bridge and on the bank, especially suitable for narrow river and canal sites in water towns, and completely eliminating the space occupied by external equipment sweeping. In terms of force distribution, the traditional single-sided hydraulic drive scheme generates an off-center load moment of about 900 kN·m when the bridge body rotates to the middle position of 30 degrees, resulting in a difference of 150% in the reaction force of the roller support on both sides of the arc track 300; the present invention adopts two drive motors 340 symmetrically arranged, the off-center load moment cancels each other out, and the difference in the reaction force of the roller support on both sides of the arc track 300 does not exceed 5%, which is 97% lower than the traditional scheme, effectively eliminating the problems of single-sided track wear and roller wear.

[0092] Compared with the closest prior art, namely the gear and rack drive device for opening bridges disclosed in Chinese patent document CN107022950A, this invention has the following substantial differences and technical advantages. CN107022950A is applicable to single-span or double-span vertical rotating opening bridges, and its gear and rack drive the bridge body to rotate in a straight line, which cannot be applied to the arc-shaped rotation motion of horizontal rotating pedestrian bridges. This invention, by adopting a technical solution of arranging an arc-shaped track 300 and driving pins 320 along the arc-shaped track 300, enables the driving gear 330 to drive the rotating bridge body unit 2 along the arc-shaped trajectory, realizing the motor pin drive of the horizontal rotating opening bridge, filling the technical gap of motor pin drive technology in the field of horizontal rotating opening bridges. CN107022950A lacks an arc-shaped track 300 and a buffer limiting mechanism, failing to address the issue of rigid impact on the bridge body at extreme positions during horizontal rotation. This invention, by incorporating elastic buffers 310 at the 0-degree and 60-degree extreme positions of the arc-shaped track 300, combined with the progressive torque output strategy and segmented deceleration operation strategy of the drive motor 340, achieves impact-free and precise stopping of the horizontal rotating bridge body under high-frequency opening and closing conditions throughout the year. The drive unit of CN107022950A is exposed within the bridge structure, failing to meet the requirement of concealed equipment for ancient building style control. This invention integrates all drive equipment, including the drive motor 340, reducer, and frequency converter, within a closed cavity in the equipment compartment at the rear of the rotating bridge unit 2, ensuring that all drive equipment is concealed and meeting the visual requirements of ancient building style control. CN107022950A lacks emergency opening and closing mechanisms, making it impossible to open the navigation channel after equipment damage or mains power outages. This invention, by reserving a standardized manual input interface at the tail of the drive motor 340 and providing a clutch mechanism, achieves emergency manual opening and closing functionality in case of mains power interruption or drive motor 340 failure, ensuring that civilian vessel navigation activities are not affected by sudden malfunctions. Actual operational data from a completed engineering application, with over 36 months of safe operation and over 200 fault-free openings and closings, further verifies the reliability and practicality of this invention.

[0093] Although the technical solutions of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. For those skilled in the art, other modifications can be easily made. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details and embodiments shown and described herein.

Claims

1. A horizontal rotary pedestrian bridge system driven by a single-pivot motor pin tooth, characterized in that, include: A fixed base unit is installed on the riverbank; The rotary bridge unit is installed on the fixed base unit in a single-support horizontal rotation manner, and can rotate horizontally between the closed position and the open position around the vertical rotation axis. The motor pin drive unit includes a drive motor, a drive gear, a drive pin, an arc-shaped track, and an elastic buffer; the drive motor drives the drive gear to mesh with the drive pin and transmits driving force along the arc-shaped track; The elastic buffer is positioned at the extreme position of the arc-shaped track to absorb rotational impact; The drive gear and the drive pin are arranged along the arc-shaped track, and the meshing force is transmitted along the tangential direction of the arc-shaped track; The meshing transmission between the drive gear and the drive pin adopts a continuous multi-point meshing method. At any angle position from 0 degrees to 60 degrees of bridge rotation, the drive gear and the drive pin always maintain at least two meshing points in contact at the same time. When the drive motor starts, it adopts a progressive torque output strategy, gradually increasing the output torque from a standstill to the rated value. The meshing force between the drive gear and the drive pin is gradually established along the tangent direction of the arc track. When the bridge body rotates to near the limit position of the arc track, the drive motor performs segmented deceleration. The rotation speed of the bridge body gradually decreases as it approaches the limit position, and it contacts the elastic buffer at a low speed. The elastic buffer provides elastic buffering at the limit position of the arc track, absorbing the residual kinetic energy of the bridge body and achieving a precise stop without impact. The progressive torque output strategy of the drive motor and the segmented deceleration operation constitute a complete start-stop operation sequence control logic. During the start-up phase, the drive motor gradually increases its torque from a standstill to its rated torque. The meshing force between the drive gear and the drive pin is gradually established along the tangent of the arc-shaped track, allowing the bridge to smoothly transition from a standstill to a uniform rotational state. This avoids localized stress concentration on the drive pin tooth surface caused by gear meshing impact during startup. During the uniform speed operation phase, the drive motor maintains a constant output torque, and the drive gear and drive pin continuously and stably mesh along the arc-shaped track, allowing the bridge to run smoothly at a set rotational speed. During the deceleration and stopping phase, the bridge rotates to the limit position of the arc-shaped track. At this time, the drive motor performs segmented deceleration operation, and the bridge body rotation speed gradually decreases as it approaches the limit position, making low-speed contact with the elastic buffer. The elastic buffer provides elastic buffering at the limit position of the arc track, absorbing the residual kinetic energy of the bridge body and eliminating rigid impact between the steel structure and the transmission components. Combined with segmented deceleration, the bridge body achieves a precise stop at the limit position without impact. The start-up phase and the deceleration and stopping phase are smoothly connected by a uniform speed operation phase. The three phases constitute a complete opening and closing operation sequence, ensuring that the transmission components of the bridge body wear evenly, the track does not deform, and the stopping position does not deviate under high-frequency opening and closing conditions throughout the year.

2. The single-pivot motor pin-driven horizontal rotary pedestrian bridge system as described in claim 1, characterized in that, The fixed base unit includes a concrete rotating bearing, a bridge body connecting embedded part, a bridge body connecting embedded part, an H-beam, a protective casing, and drainage holes. The concrete rotating bearing supports the rotation of the bridge body. The bridge body connecting embedded part and the bridge body connecting embedded part achieve a hidden connection between the bridge body and the base. The H-beam serves as a pile foundation support. The protective casing provides protection and shielding for the H-beam. The drainage holes drain water accumulated inside the base. The rotating bridge body unit integrates the drive motor into the equipment compartment at the rear of the bridge body. All drive equipment is hidden and internal, without hydraulic cylinders or pipelines. The concrete rotating bearing and the bridge body connecting embedded part form a closed rotating bearing structure. The bearing platform surface of the concrete rotating bearing and the embedded connection surface of the bridge body connecting embedded part adopt a sealed contact design to prevent surface water from seeping into the base along the rotating bearing surface. Both the bridge body connecting embedded part and the bridge body connecting embedded part are hidden connection structures, with the connection nodes embedded inside the concrete and not exposed on the bridge body surface.

3. The single-pivot motor pin-driven horizontal rotary pedestrian bridge system as described in claim 1, characterized in that, The drive motor has a standardized manual input interface at its tail, which is independent of the drive gear's transmission link. When the drive motor is working normally, the manual input interface is disconnected. When the mains power is interrupted or the drive motor fails, maintenance personnel can directly drive the drive gear to rotate through the manual input interface. The drive gear meshes with the drive pin, and the bridge body rotates along the arc-shaped track to the navigation station. During manual operation, the bridge body's rotation speed is controlled by the operator. When approaching the limit position of the arc-shaped track, the elastic buffer still provides elastic cushioning to ensure that the bridge body can achieve a precise stop at the limit position without impact during manual opening and closing.

4. The single-pivot motor pin-driven horizontal rotary pedestrian bridge system as described in claim 2, characterized in that, The drainage holes are located in the lower area of ​​the fixed base unit, using gravity to drain rainwater or seepage water accumulated inside the base, keeping the base dry and preventing corrosion of the concrete rotating support and the H-beam in a humid environment; the protective sleeve provides protection and shielding for the H-beam, achieving physical isolation between the H-beam and the external environment, while also shielding the exposed steel structure of the H-beam, meeting the visual requirement of ancient building style control that equipment should not be exposed.

5. The single-pivot motor pin-driven horizontal rotary pedestrian bridge system as described in claim 4, characterized in that, The H-beams serve as pile foundation supports and are connected to the concrete rotating bearings via pile caps, enabling the gradual transfer of bridge loads to the deep foundation. The arrangement of the H-beam pile foundations does not spatially interfere with the rotation path of the arc-shaped track, and the drive path conforms to the bridge's rotation trajectory, avoiding the large-area sweeping of traditional hydraulic cylinders that would occupy pile foundation space. The concrete rotating support is connected to the bridge body through a pier cap.

6. The single-pivot motor pin-driven horizontal rotary pedestrian bridge system as described in claim 3, characterized in that, The output shaft of the drive motor is equipped with an electromagnetic brake, and a clutch mechanism is provided between the standardized manual input interface of the drive motor and the drive gear. When the drive motor is working normally, the clutch mechanism is in the disengaged state, the manual input interface is disconnected from the transmission link of the drive gear, and the electromagnetic brake is controlled according to the conventional operating logic, which does not affect the operating efficiency of the drive motor driving the drive gear. When the mains power is interrupted or the drive motor fails, the clutch mechanism switches to the engaged state, the manual input interface connects to the transmission link of the drive gear, and the electromagnetic brake is de-energized and released, allowing the drive motor rotor to rotate freely. Maintenance personnel can directly drive the drive gear to rotate through the manual input interface. The drive gear meshes with the drive pin, and the bridge body rotates along the arc-shaped track. During manual operation, the rotation speed of the bridge body is controlled by the operator. When approaching the limit position of the arc-shaped track, the elastic buffer still provides elastic cushioning to ensure that the bridge body achieves a precise stop at the limit position without impact during manual opening and closing.

7. The single-pivot motor pin-driven horizontal rotary pedestrian bridge system as described in claim 1, characterized in that, The drive motor is built into the equipment compartment at the rear of the slewing bridge unit. The installation position is located in a closed cavity on one side of the rotation center of the bridge body, completely isolated from the external environment. The operating noise of the equipment is less than 40 decibels, which meets the requirements of a quiet environment in the water town residential area. The drive motor drives the drive gear through a reducer. The reducer is integrated with the drive motor or externally installed at the output end of the drive motor. The drive gear meshes with the drive pin teeth of the fixed section of the bridge body, causing the bridge body to rotate along the rotation center.

8. The single-pivot motor pin-driven horizontal rotary pedestrian bridge system as described in claim 1, characterized in that, Also includes: A dual-position mechanical locking unit, comprising a closed passage lock assembly and a fully open passage lock assembly; The closed passage lock assembly is installed at the end of the walkway on the opposite bank of the river. After the rotating bridge unit rotates to the 0° closed position, the locking tongue of the closed passage lock assembly is inserted laterally into the corresponding base lock hole to eliminate the pedestrian gap between the bridge and the walkway. The bolt strength of the fully open navigation lock assembly is higher than that of the closed passage lock assembly. After the slewing bridge unit rotates to the 60-degree opening position, the bolt of the fully open navigation lock assembly is inserted into the locking base set on the shore support to resist the wind load and pedestrian load on the bridge body in the long-term open state and keep the bridge body from shaking and slipping throughout the entire process. Both the closed access lock assembly and the fully open access lock assembly are equipped with alignment sensors. When the slewing bridge unit is in a stationary state and the alignment sensor detects that the bridge body is not fully aligned at the 0-degree closed position or the 60-degree open position, the motor pin drive unit is forcibly locked and prohibited from starting the slewing.

9. The single-pivot motor pin-driven horizontal rotary pedestrian bridge system as described in claim 2, characterized in that, The main beam of the rotating bridge unit is welded from high-strength structural steel. A pre-arch is set at the far end of the rotating bridge to offset the effects of deflection and temperature changes during bridge rotation on the opening and closing of the bridge, ensuring smooth opening and closing. The closed cavity at the tail of the bridge is filled with counterweight concrete to improve the stability of the bridge along the center of rotation. The pre-embedded parts connecting the bridge body in the fixed base unit cooperate with the pre-embedded parts connecting the bridge body to realize the connection between the rotating support of the bridge body and the bridge body through the pier. The bridge body can rotate horizontally in one direction from 0 degrees to 60 degrees. The 0-degree position closes and connects the pedestrian walkways on both banks for residents' daily walking, while the 60-degree position fully opens the river channel parallel to the bank for continuous passage of folk boat convoys.

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