Stairway bridge device for inspection and maintenance of cables of the FAST ring beam from the ground

Abstract

The utility model discloses a stair bridge device for the inspection and maintenance of the cable crane of the FAST ring beam from the ground, which is used for connecting the cable crane transfer trolley on the ring beam and the fixed stair, and comprises: a movable pedal, which is hinged to the top platform of the stair and is switched between the retracted state and the horizontal unfolded state; a sliding guardrail, which is arranged along the side edge of the top platform of the stair and horizontally slides to the position of the transfer trolley guardrail; a driving mechanism, which controls the retraction and unfolding of the movable pedal and the displacement of the sliding guardrail through a hand winch; after the movable pedal is unfolded, the movable pedal maintains a set safety distance from the cable crane transfer trolley on the ring beam and is adapted to the radial sliding of the ring beam. The utility model designs the stair bridge device for the inspection and maintenance of the cable crane of the FAST ring beam from the ground according to the specific structure of the FAST ring beam and the cable crane, ensures that the maintenance personnel can safely and conveniently pass through, and eliminates the safety hazards.

Description

Technical Field

[0001] This utility model relates to the field of FAST radio telescope technology and is a stair bridge device for inspection and maintenance of the FAST ring beam cable-stayed bridge from the ground. Background Technology

[0002] The FAST cable crane and transfer locomotive, located on the ring beam, are specialized equipment used for the installation of the FAST reflector. After the telescope is completed, they are used for the inspection and maintenance of the ring beam reflector and other components. The cable crane and transfer locomotive are usually parked at position 1H on the ring beam, and are accessed and de-accessed via ground ladders.

[0003] A staircase for inspection and maintenance of the cable hoist is provided at position 1H. In order for personnel to safely reach the transfer locomotive, a safe bridge device needs to be installed between the staircase and the transfer locomotive. Utility Model Content

[0004] In view of the problems existing in the prior art, the purpose of this utility model is to provide a bridge crossing device with an improved structure.

[0005] To achieve the above objectives, this utility model provides a stair bridge device for accessing and maintaining the FAST ring beam cable-stayed crane from the ground, connecting the cable-stayed crane transfer vehicle (2) on the ring beam with a fixed staircase (3), comprising: The movable tread (4) is hinged to the top platform (31) of the stairs and can switch between a retracted state and a horizontally extended state. The sliding guardrail (5) is installed along the side of the top platform (31) of the stairs and slides horizontally to the position of the transfer vehicle guardrail (1); The drive mechanism (6) controls the extension and retraction of the movable pedal (4) and the displacement of the sliding guardrail (5) through a hand-cranked winch (61); After the movable pedal (4) is unfolded, it maintains a set safe distance from the cable crane transfer vehicle (2) to adapt to the radial sliding of the ring beam.

[0006] Furthermore, the surface of the movable pedal (4) is provided with anti-slip texture or covered with anti-slip rubber sleeve, the pedal width is ≥800mm, and the load-bearing capacity after unfolding is ≥3.0 kN / m².

[0007] Furthermore, the sliding guardrail (5) includes: Vertical poles (51), spacing ≤ 300mm; Horizontal rings (52), with a spacing of ≤1500mm, form a cage structure with a diameter ≥700mm; Bottom rail (53) is embedded in the crossbeam of the top platform of the staircase.

[0008] Furthermore, the drive mechanism (6) includes: A steel wire rope (62) connects the movable pedal (4) to the hand-cranked winch (61). The gear and rack assembly drives the sliding guardrail (5) to move horizontally; A self-locking device prevents the movable pedal (4) from falling unexpectedly.

[0009] Furthermore, the hand-cranked winch (61) is mounted on top of the vertical pole (51) via a base (64).

[0010] Furthermore, a handle (65) is provided on the base (64). Rotating the handle (65) drives the hand-cranked winch (61) to rotate, which drives the wire rope (62) to be wound and unwound, thereby driving the folding and flattening operation of the movable pedal (4).

[0011] Furthermore, a rack (54) is provided on the upper part of the sliding guardrail (5), and a toothed disc (63) is provided on the hand-cranked winch (61). The rack (54) and the toothed disc (63) together form the gear rack assembly.

[0012] Furthermore, when the handle (65) is turned to drive the hand winch (61) to rotate, the gear plate (63) drives the rack (54) to move horizontally, thereby driving the sliding guardrail (5) to move horizontally.

[0013] Furthermore, the movable tread (4) includes a platform support (41), with a lifting lug (42) at the front end and a hinge ring (43) at the rear end. The lifting lug (42) is fixedly connected to the wire rope (62), and the hinge ring (43) is used for hinged connection with the top platform (31) of the stairs.

[0014] Furthermore, the staircase (3) is a 5-flight spiral structure with a single section height ≤ 4m, a rest platform (32) in the middle, an overall height of 8.42m, and a width of 2.02m. This utility model, specifically designed for the FAST ring beam's unique structure, provides a staircase bridge device for accessing and maintaining the FAST ring beam via cable hoisting from the ground, eliminating safety hazards, ensuring safe passage for personnel, and guaranteeing work safety. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of this utility model after installation; Figure 2 yes Figure 1 Enlarged view of a portion of the image; Figure 3 This is a schematic diagram of the structure of the movable pedal installation part; Figure 4 This is a schematic diagram of the platform support structure; Figure 5 This is a top view of the structure of this utility model after installation; Figure 6This is a side view of the structure after installation of this utility model. Figure 1 ; Figure 7 This is a side view of the structure after installation of this utility model. Figure 2 ; Figure 8 This is a schematic diagram of a hand-cranked winch. Figure 9 This is a stress result analysis diagram; Figure 10 This is a graph showing the displacement results. Detailed Implementation

[0016] The technical solution of this utility model will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0017] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0018] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0019] The following combination Figures 1-10 The specific embodiments of this utility model will be described in detail below. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the scope of this utility model.

[0020] The FAST cable crane and transfer locomotive, located on the ring beam, are specialized equipment used for the installation of the FAST reflector. After the telescope is completed, they are used for the inspection and maintenance of the ring beam reflector and other components. The cable crane and transfer locomotive are usually parked at position 1H on the ring beam, and are accessed and de-accessed via ground ladders.

[0021] The transfer locomotive is parked on the upper track of the ring beam. Due to the 500-meter diameter of the FAST ring beam, the radial slippage of the ring beam can reach up to 250mm due to the tension of the cable net and thermal expansion and contraction. The staircase cannot be designed to directly connect with the transfer locomotive and must maintain a safety distance of about 1000mm. The staircase bridge device of this utility model, which is used to go up and down the FAST ring beam cable crane for inspection and maintenance, allows people to pass through the staircase to the cable crane transfer car.

[0022] Because electronic equipment exceeding the inspection standards would cause electromagnetic interference to FAST observations, an electrically driven structure should not be designed. Therefore, in this invention, a movable step platform is installed on the stairs, which is raised and lowered by a hand-cranked winch. Normally, it is in a retracted state. When maintenance work is required, personnel reach the top of the stairs and lower the movable step by hand-cranking the winch. To ensure the safety of personnel passage, a movable guardrail is also designed, which can slide from the stairs to the transfer locomotive position, allowing personnel to pass safely. After passing, the personnel on the stairs retract the safety guardrail, raise the movable step by hand-cranking the winch, and close the transfer locomotive guardrail door.

[0023] This utility model provides a stair bridge device for accessing and maintaining the FAST ring beam via cable hoisting from the ground, connecting the cable hoisting transfer vehicle 2 on the ring beam with a fixed staircase 3, including: The movable tread 4 is hinged to the top platform 31 of the stairs and can switch between a retracted state and a horizontally extended state. The sliding guardrail 5 is installed along the side of the top platform 31 of the stairs and slides horizontally to the position of the transfer vehicle guardrail 1. The drive mechanism 6 controls the extension and retraction of the movable pedal 4 and the displacement of the sliding guardrail 5 via a hand-cranked winch 61. The movable tread 4 includes a platform support 41. The platform support 41 has a lifting lug 42 at its front end and a hinge ring 43 at its rear end. The lifting lug 42 is fixedly connected to a wire rope 62, and the hinge ring 43 is used for hinged connection with the top platform 31 of the stairs. When unfolded, the movable tread 4 maintains a predetermined safe distance from the cable-stayed transport trolley 2, adapting to the radial sliding of the ring beam. Generally, a safe distance of approximately 1000mm is maintained, depending on usage requirements. The surface of the movable tread 4 is provided with anti-slip texture or covered with an anti-slip rubber sleeve. The tread width is ≥800mm, and the load-bearing capacity after unfolding is ≥3.0 kN / m².

[0024] The sliding guardrail 5 includes: The horizontal railing 56 extends to form left and right guardrails when the movable step 4 is placed horizontally to prevent people from falling; when the movable step 4 is retracted to the horizontal state, the horizontal railing 56 retracts and is placed on the crossbeam of the top platform of the stairs. Vertical poles 51, spacing ≤ 1000mm ≤ 1500mm, forming a passage for people to pass between two vertical poles 51; A number of horizontal hoops 52 are set on the crossbeam of the top platform of the stairs. The horizontal railing 56 is inserted into the horizontal hoops 52, so that the horizontal railing 56 can only slide within the direction defined by the horizontal hoops 52. Bottom guide rail 53 is provided on the crossbeam of the top platform of the stairs to facilitate the sliding of the horizontal rail 56. The horizontal rail 56 is placed on the bottom guide rail 53. Under the combined action of the horizontal hoop 52 and the bottom guide rail 53, the horizontal rail 56 can extend and retract along the crossbeam of the top platform of the stairs.

[0025] In this utility model, a drive mechanism 6 is provided for driving the movable pedal 4 and the sliding guardrail 5. The drive mechanism 6 includes: A steel wire rope 62 connects the movable pedal 4 to a hand-cranked winch 61. The hand-cranked winch 61 has a space to accommodate the steel wire rope 62 after it is wound. The hand-cranked winch 61 is mounted on the top of the vertical pole 51 via a base 64. A handle 65 is mounted on the base 64. Rotating the handle 65 causes the hand-cranked winch 61 to rotate, which drives the steel wire rope 62 to be wound up and down, thereby driving the folding and flattening operation of the movable pedal 4. A gear and rack assembly drives the sliding guardrail 5 to move horizontally; a rack 54 is provided on the upper part of the sliding guardrail 5, and a toothed disc 63 is provided on the hand-cranked winch 61. The rack 54 and the toothed disc 63 together form the gear and rack assembly. A self-locking device prevents the movable pedal 4 from falling unexpectedly. This self-locking device can be a ratchet structure located at the connection between the handle 65 and the hand-cranked winch 61, or other anti-rotation mechanical mechanisms.

[0026] When the handle 65 is turned, the hand-cranked winch 61 rotates, and the gear plate 63 drives the rack 54 to move horizontally, thereby driving the sliding guardrail 5 to move horizontally.

[0027] In this utility model, the staircase 3 is a 5-flight spiral structure with a single section height of ≤4m, a rest platform 32 in the middle, an overall height of 8.42m, and a width of 2.02m.

[0028] Main structure: Q235B carbon structural steel; Pedal: The surface must be treated with an anti-slip coating; Connectors: High-strength bolts (grade 8.8 and above), with anti-corrosion treatment.

[0029] Structural form: Type: Vertical ladder, inclined ladder (inclination angle ≤75°).

[0030] Cage requirements: Diameter ≥700mm, spacing of vertical bars ≤300mm, spacing of horizontal ring hoops ≤1500mm.

[0031] Ladder section height: The height of a single section of climbing ladder ≤4m, and an intermediate rest platform shall be provided if the limit is exceeded.

[0032] The staircase is 8.42 meters in height, 2.02 meters in width, and 4.07 meters in length, and is designed as a 5-flight return staircase; the lower first floor is provided with a enclosure and an access door with lock; the top platform is designed with a guardrail of no less than 1.1m in height, and retractable pedals are arranged to lead from the top of the staircase to the cable crane.

[0033] Anti-slip measures: The surface of the rungs shall be knurled, textured or covered with anti-slip rubber sleeves.

[0034] The opening rate of the platform grating plate ≤20% to prevent water accumulation and slipping.

[0035] For this utility model, surface treatment and anti-corrosion of the overall structure: (1) Cold zinc spray primer: 80μm (2) Epoxy micaceous iron intermediate paint: 120μm (3) Polyurethane topcoat: 60μm, tested by ultrasonic thickness gauge (GB / T 13452).

[0036] For this utility model, calculation of ladder beam: The maximum inclined length of the staircase is 3.1 meters, the width is 0.8 meters, the angle is 33°, and No. 8 channel steel is adopted. The staircase load is designed as 3kN / ㎡.

[0037] Maximum bending moment: M=3000×0.4×0.84×3^2 / 8=1134Nm 1. Bending stress: 1134 / (1.0×25.3e-6)=45Mpa<215Mpa, the stress meets the requirements.

[0038] 2. Deflection: 5×3000×0.4×0.84×3^4 / (384×2.1e11×101.3e-8)=5mm<L / 250, the deflection meets the requirements.

[0039] For this utility model, frame calculation: 1. The frame is modeled by ANSYS finite element method, the beam188 element is adopted, and all nodes are set as rigid connection nodes. The column base adopts hinged constraint.

[0040] 2. Load application: 1) Uniformly distributed loads are applied on the ladder beams and the rest platform beams, and the loads are calculated as 3kN / ㎡; 2) Apply a wind load of 300N to the beam-column joints on each floor as a concentrated load (approximately 0.4kN / ㎡ wind load).

[0041] Analysis of the frame calculation results of this utility model: 1) Maximum stress: 85.3 MPa < 215 MPa, which meets the requirements.

[0042] 2) The maximum displacement of the column top is 7mm, which meets the requirements.

[0043] 3) The natural frequency is 4.4Hz, which is greater than 3Hz, thus meeting the requirements.

[0044] Any process or method described in the flowcharts of this utility model or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or more executable instructions for implementing a particular logical function or process, which can be implemented in any computer-readable medium for use by an instruction execution system, apparatus, or device. The computer-readable medium can be any medium containing a program for storage, communication, propagation, or transmission for use by the execution system, apparatus, or device, including read-only memory, magnetic disks, or optical disks.

[0045] In the description of this specification, the references to terms such as "embodiment," "example," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, those skilled in the art can combine or integrate different embodiments or examples and features described in this specification without creating contradictions. Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A staircase bridge device for ascending and descending from the ground to the FAST ring beam cable-stayed inspection and maintenance facility, characterized in that, The bridge-crossing device is used to connect the cable-stayed transfer vehicle (2) on the ring beam with the fixed staircase (3), and includes: The movable tread (4) is hinged to the top platform (31) of the stairs and can switch between a retracted state and a horizontally extended state. The sliding guardrail (5) is installed along the side of the top platform (31) of the stairs and slides horizontally to the position of the transfer vehicle guardrail (1); The drive mechanism (6) controls the extension and retraction of the movable pedal (4) and the displacement of the sliding guardrail (5) through a hand-cranked winch (61); After the movable pedal (4) is unfolded, it maintains a set safe distance from the cable crane transfer vehicle (2) to adapt to the radial sliding of the ring beam.

2. The staircase bridge device for inspection and maintenance of the FAST ring beam cable-stayed structure as described in claim 1, characterized in that, The surface of the movable pedal (4) is provided with anti-slip texture or covered with anti-slip rubber sleeve, the pedal width is ≥800mm, and the load-bearing capacity after unfolding is ≥3.0 kN / m².

3. The staircase bridge device for inspection and maintenance of the FAST ring beam cable-stayed structure from the ground, as described in claim 1, is characterized in that... The sliding guardrail (5) includes: Vertical poles (51), spacing ≤ 300mm; Horizontal rings (52), with a spacing of ≤1500mm, form a cage structure with a diameter ≥700mm; Bottom rail (53) is embedded in the crossbeam of the top platform of the staircase.

4. The staircase bridge device for inspection and maintenance of the FAST ring beam cable-stayed structure as described in claim 3, characterized in that, The drive mechanism (6) includes: A steel wire rope (62) connects the movable pedal (4) to the hand-cranked winch (61). The gear and rack assembly drives the sliding guardrail (5) to move horizontally; A self-locking device prevents the movable pedal (4) from falling unexpectedly.

5. The staircase bridge device for inspection and maintenance of the FAST ring beam cable-stayed structure from the ground, as described in claim 4, is characterized in that... The hand-cranked winch (61) is mounted on the top of the vertical pole (51) via a base (64).

6. The staircase bridge device for inspection and maintenance of the FAST ring beam cable-stayed structure from the ground, as described in claim 5, is characterized in that... A handle (65) is provided on the base (64). Rotating the handle (65) drives the hand-cranked winch (61) to rotate, which drives the wire rope (62) to be wound up and down, thereby driving the folding and flattening operation of the movable pedal (4).

7. The staircase bridge device for inspection and maintenance of the FAST ring beam cable-stayed structure from the ground, as described in claim 6, is characterized in that... The upper part of the sliding guardrail (5) is provided with a rack (54), and the hand-cranked winch (61) is provided with a toothed disc (63). The rack (54) and the toothed disc (63) together form the gear rack assembly.

8. The staircase bridge device for inspection and maintenance of the FAST ring beam cable-stayed structure from the ground, as described in claim 7, is characterized in that... When the handle (65) is turned to drive the hand winch (61) to rotate, the toothed disc (63) drives the rack (54) to move horizontally, thereby driving the sliding guardrail (5) to move horizontally.

9. The staircase bridge device for inspection and maintenance of the FAST ring beam cable-stayed structure from the ground, as described in claim 1, is characterized in that... The movable tread (4) includes a platform support (41), with a lifting lug (42) at the front end and a hinge ring (43) at the rear end. The lifting lug (42) is fixedly connected to the wire rope (62), and the hinge ring (43) is used for hinge connection with the top platform (31) of the stairs.

10. The staircase bridge device for inspection and maintenance of the FAST ring beam cable-stayed structure from the ground, as described in claim 1, is characterized in that... The staircase (3) is a 5-flight spiral structure with a single section height of ≤4m and a rest platform (32) in the middle. The overall height is 8.42m and the width is 2.02m.

Images