Bridge device

Abstract

To prevent the fall of a worker by preventing the separation of the tip part of a bridge from a target facility even when instantaneous and irregular swing is generated by the influence of waves or the like.SOLUTION: A bridge-building device is provided with a bridge-building part 4 which operates in a tilting manner, an access part 6 coupled to the bridge-building part 4 so as to freely incline, and a link mechanism 7 / an inclination control mechanism 9 for controlling the inclination of the access part 6 to the bridge-building part 4 and keeping the angle of the access part 6 in the horizontal direction constant. The access part 6 has a fixed stage 61 connected to the bridge-building part 4, a moving stage 62 movable in the longitudinal direction with respect to the fixed stage 61, and energizing means interposed between the fixed stage 61 and the moving stage 62 to energize the moving stage 62 forward so as to project forward from the fixed stage 61.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a bridge device, and more particularly to a mechanism for preventing falling from a bridge when transferring from a ship to an offshore facility. [Background technology]

[0002] A known mechanism for suppressing the swaying of a bridge girder section and maintaining stability when transferring from a ship to an offshore facility in a rough wave environment is a movable pier that has a top plate supported by a six-degree-of-freedom motion base and a bridge girder section extending laterally from the upper surface of the top plate, the bridge girder section being constructed by connecting a number of divided bodies in the longitudinal direction, at least one horizontal rotation mechanism connecting adjacent divided bodies in the longitudinal direction, and at least one vertical rotation mechanism connecting adjacent divided bodies in the longitudinal direction, the divided bodies connected via this horizontal rotation mechanism being rotatable horizontally around the horizontal rotation mechanism and the divided bodies connected via this vertical rotation mechanism being rotatable vertically around the vertical rotation mechanism, and further, a magnet attached to the tip of the bridge girder section is attracted to and connected to the offshore facility (Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2015-137451 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the case of the movable pier in Patent Document 1, in the event of irregular and sudden waves, there is a risk that the tip of the bridge girder or the connections between the sections may be damaged, because the tip of the bridge girder is connected to the offshore equipment by magnets.In that case, there is a problem that workers attempting to transfer to the pier may fall off, or the tip of the bridge girder may collide with the offshore equipment.

[0005] Therefore, an object of the present invention is to provide a bridge device that can prevent the tip of the bridge from detaching from the target facility and prevent workers from falling off even when momentary, irregular vibrations occur due to the effects of waves or the like. [Means for solving the problem]

[0006] In order to solve the above problems, the bridging device of the present invention has a bridging section, one end of which is supported on an axis and can tilt upward and downward, an access section connected to the other end of the bridging section so that they can be freely tilted relative to each other, and a tilt control mechanism that controls the tilt of the access section relative to the bridging section to keep the angle of the access section relative to the horizontal direction constant, and is characterized in that the access section has a fixed stage connected to the other end of the bridging section, a movable stage that can move in the forward and backward directions relative to the fixed stage, and a biasing means interposed between the fixed stage and the movable stage for biasing the movable stage forward so that it extends forward from the fixed stage.

[0007] The bridging device of the present invention may have a tilt control mechanism that includes a parallel link that is arranged parallel to the longitudinal direction of the bridging section and has one end on the same side as the one end of the bridging section supported by an axis so as to tilt upward and downward while remaining parallel to the longitudinal direction of the bridging section, and a link front end connecting post that is rotatably connected to the other end of the bridging section and to the other end of the parallel link so that the tilt angle relative to the horizontal direction is kept constant when the bridging section and the parallel link tilt, and the tilt angle of the access section relative to the link front end connecting post may be fixed at a predetermined angle.

[0008] The bridging device of the present invention may be configured so that the tilt control mechanism includes an extension / retraction actuator having a cylinder tube and a piston rod that can move back and forth relative to the cylinder tube and is attached to the bridging portion, and a link member that connects the piston rod and the fixed stage, and the access portion tilts relative to the bridging portion via the link member as the extension / retraction actuator expands and contracts in response to the tilting movement of the bridging portion.

[0009] The bridging device according to the present invention may further include shock absorbing means interposed between the fixed stage and the biasing means for absorbing a rearward load acting on the biasing means due to an external force acting on the movable stage.

[0010] The bridging device according to the present invention may be configured so that at least one of a cushion member and a roller is provided at the front end of the moving stage.

[0011] The bridging device of the present invention may be equipped with at least one of a light and a speaker that is activated when the amount of movement of the movable stage in the fore-and-aft direction relative to the fixed stage approaches or reaches its maximum possible amount of movement.

[0012] The bridging device according to the present invention may further include at least one of a light and a speaker that operates in conjunction with whether or not the tip of the moving stage is in contact with the target facility. Effect of the Invention

[0013] According to the bridging device of the present invention, the access section has a fixed stage connected to the other end of the bridging section, a mobile stage movable in the fore-and-aft direction relative to the fixed stage, and a biasing means interposed between the fixed stage and the mobile stage for biasing the mobile stage forward so that it protrudes forward from the fixed stage. Therefore, when the hull is caused to momentarily and irregularly sway due to irregular and sudden waves, changing the fore-and-aft distance between the access section and the landing target of the offshore facility, the mobile stage can move forward and backward relative to the fixed stage in accordance with the change in the fore-and-aft distance, thereby maintaining a state in which it is pressed against the landing target. This makes it possible to ensure the safety of transferring to the landing target, and also makes it possible to prevent a situation in which the access section detaches from the landing target and a gap is created between the mobile stage and the landing target, causing a worker to lose his footing or even fall. It is also possible to prevent a situation in which the access section hits (or, gets stuck on) the landing target and the bridging section is unable to tilt upward / downward.

[0014] According to the bridging device of the present invention, if the angle of inclination of the access part relative to the front end connecting pillar of the link, which maintains a constant angle of inclination relative to the horizontal direction when the bridging part and the parallel link tilt, is fixed at a predetermined angle, the stage of the access part can be always kept in a constant posture when the bridging part and the parallel link tilt, and the plate surface of the stage can always be kept horizontal, for example. This makes it possible to prevent a situation in which the stage of the access part tilts and the worker loses his balance, falls, or leans forward and crashes into the landing target, or even falls, thereby ensuring the safety of transferring to the landing target.

[0015] According to the bridging device of the present invention, when the access section is made to tilt relative to the bridging section by the extension and retraction actuator performing extension and retraction in response to the tilting movement of the bridging section, the stage of the access section can always be kept in a constant posture when the bridging section tilts, and the plate surface of the stage can always be kept horizontal, for example. This makes it possible to prevent a situation in which the stage of the access section tilts and the worker loses his balance, falls, or leans forward and crashes into the landing target, or even falls off, thereby ensuring the safety of transferring to the landing target.

[0016] If the bridging device of the present invention is configured to have an impact absorbing means for absorbing the rearward load acting on the biasing means, it is possible to prevent excessive load from acting on the biasing means interposed between the fixed stage and the movable stage, thereby preventing damage to the biasing means, thereby maintaining the integrity of the bridging device and ensuring the safety of workers attempting to transfer from the access section to the landing target.

[0017] When the bridging device of this invention is equipped with a cushion member or rollers at the front end of the moving stage, it becomes possible to prevent damage to the access part and the landing target or offshore equipment when they come into contact with each other, and it becomes possible to ensure the sliding properties of the access part and the landing target or offshore equipment when they move relative to each other in the vertical direction while in contact with each other, thereby preventing damage to each of them.In turn, it becomes possible to maintain the integrity of the bridging device and ensure the safety of workers attempting to transfer from the access part to the landing target.

[0018] If the bridging device of the present invention is equipped with lights and speakers that operate according to the amount of forward and backward movement of the moving stage, it can notify workers when there is no room for movement of the moving stage or when the amount of movement has reached its maximum, making it possible to ensure the safety of workers even more reliably.

[0019] If the bridging device of the present invention is equipped with lights and speakers that operate in conjunction with whether or not the tip of the moving stage is in contact with the target equipment, it can inform workers whether or not the tip of the moving stage is in contact with the target equipment, making it possible to ensure the safety of workers even more reliably. [Brief description of the drawings]

[0020] [Figure 1] 1 is a front right upper perspective view showing an overall structure of a bridging device according to a first embodiment of the present invention; [Diagram 2] FIG. 2 is a rear left upper perspective view of the bridging device of FIG. 1; [Diagram 3] 2 is a side view of the bridging device of FIG. 1, showing a state in which the longitudinal direction of the bridging part is aligned with the horizontal direction and the movable stage of the access part is in a retracted position above the fixed stage. FIG. [Figure 4] 4 is a side view for explaining the operation of the bridging portion of the bridging device of FIG. 1, showing a state in which the bridging portion has been tilted upward from the state of FIG. 3. FIG. [Diagram 5] 4 is a side view for explaining the operation of the bridging portion of the bridging device of FIG. 1, showing a state in which the bridging portion has been tilted downward from the state of FIG. 3. FIG. [Figure 6] 2 is an enlarged view of a front end of a bridging portion and an access portion of the bridging device of FIG. 1. [Figure 7] 4 is a side view illustrating the operation of the access part of the bridging device in FIG. 1, showing a state in which the moving stage of the access part has moved forward from the state in FIG. 3. FIG. [Figure 8] 8 is a front right upper perspective view of the state shown in FIG. 7. [Figure 9] 8 is a rear left upper perspective view of the state in FIG. 7. [Figure 10] FIG. 11 is a side view showing the overall structure of a bridging device according to embodiment 2 of the present invention, in which the longitudinal direction of the bridging section is aligned horizontally and the movable stage of the access section is in a retracted position above the fixed stage. [Figure 11]11 is a side view for explaining the operation of the bridging portion of the bridging device of FIG. 10, showing a state in which the bridging portion has been tilted upward from the state of FIG. 10. FIG. [Figure 12] FIG. 11 is a side view showing the overall structure of a bridging device according to embodiment 3 of the present invention, in which the longitudinal direction of the bridging section is aligned horizontally and the movable stage of the access section is in a retracted position above the fixed stage. [Figure 13] 13 is a side view for explaining the operation of the bridging portion of the bridging device of FIG. 12, showing a state in which the bridging portion has been tilted upward from the state in FIG. 12. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] The present invention will be described below based on the illustrated embodiment. In the following embodiment, the case where the bridge device 1 according to the present invention is installed on a ship will be described as an example. In the following description, the front-rear, left-right, and up-down directions are defined according to the directions of arrows along the axes of a three-dimensional orthogonal coordinate system as shown in each drawing.

[0022] (Embodiment 1) 1 and 2 are perspective views showing the overall structure of a bridging device 1 according to a first embodiment of the present invention. The bridging device 1 is a mechanism that is bridged between a ship and a landing target of an offshore facility and is used when workers transfer from the ship to the offshore facility. Specific examples of the offshore facility include offshore wind power generation facilities and seabed mineral drilling platforms that are installed on the sea. Specific examples of the landing target of an offshore facility (in other words, target facility) include a vertical ladder installed on the offshore facility and a wall of the offshore facility.

[0023] The bridging device 1 according to this embodiment 1 mainly includes a motion compensation mechanism 2 installed on the deck of a ship, a main table 3 installed on top of the motion compensation mechanism 2, a bridging section 4 connected to the main table 3, a swing operation mechanism 5 for tilting (in other words, swinging) the bridging section 4, an access section 6 connected to the front end (in other words, the tip) of the bridging section 4, and a link mechanism 7 for controlling the tilt of the access section 6 relative to the bridging section 4. Note that the following description will be given on the assumption that the longitudinal direction of the bridging section 4 is aligned with the front-rear direction.

[0024] The motion compensation mechanism 2 has a hexapod configuration and is a mechanism for compensating for the motion (particularly the inclination) of the hull caused by the influence of waves and the like, and for maintaining the main table 3 horizontal.

[0025] The motion compensation mechanism 2 has a base frame 21 that is fixed to the deck of the ship, and six extendable actuators 22, one end of which is connected to the base frame 21 via a universal joint and the other end of which is connected to the main table 3 via a universal joint.

[0026] The base frame 21 is formed, for example, using a steel material, and is firmly fixed in position and installed on the deck of the ship.

[0027] Each actuator 22 is configured by, for example, an electric cylinder, and is controlled by a control device (not shown) to perform an expansion and contraction operation.

[0028] The six actuators 22 allow the motion compensation mechanism 2 to operate as a six-axis device having six degrees of freedom. Specifically, when the hull vibrates in the roll, pitch, and yaw directions due to the influence of waves or the like, the motion compensation mechanism 2 operates to keep the main table 3 horizontal by controlling the extension and contraction of each actuator 22.

[0029] The main table 3 is formed into a polygonal plate shape in a plan view, and is supported so that the direction and degree of inclination of the plate surface can be controlled by expanding and contracting six actuators 22 of the fluctuation correction mechanism 2.

[0030] In the example shown in Fig. 1 etc., an auxiliary table 31 is attached to expand the space above the main table 3. Table handrails 32 are attached to the left and right edges of the upper surface of the main table 3 and the upper surface of the auxiliary table 31, straddling the main table 3 and the auxiliary table 31. The main table 3 and the auxiliary table 31 are preferably formed to be lightweight, for example, by using an aluminum frame or adopting a honeycomb structure.

[0031] The bridge section 4 functions as a passageway (in other words, a bridge girder) that spans between the main table 3 and the landing target of the offshore facility, and is formed in a long plate shape. Bridge handrails 41 are attached to the left and right edges of the upper surface of the bridge section 4, respectively.

[0032] The bridging part 4 has an end portion on the main table 3 side (i.e., a rear end portion) supported by a bridging rear end rotation shaft 71 arranged along the left-right direction and rotatably connected to the front end portion of the main table 3. As a result, the bridging part 4 is attached to the main table 3 so as to be able to tilt upward with respect to the plate surface of the main table 3 (in this case, tilting at an elevation angle as seen from the main table 3) and to be able to tilt downward (in this case, tilting at a depression angle as seen from the main table 3) with the bridging rear end rotation shaft 71 as the center of rotation. The bridging part 4 is preferably formed to be lightweight, for example, by using aluminum or fiber-reinforced plastic.

[0033] The swing operation mechanism 5 is a mechanism for tilting the bridge section 4 with respect to the main table 3 so as to correct the swaying (especially the up and down movement) of the hull caused by the influence of waves and the like, and to align the relative positional relationship in the up and down direction between the access section 6 connected to the front end (tip) of the bridge section 4 and the landing target of the offshore facility, thereby eliminating the difference in height between them. The swing operation mechanism 5 has an operation arm 51 and a drive device 52 that operates the operation arm 51.

[0034] The operating arm 51 is formed in a mountain shape (in other words, an upside-down V shape) having a bent portion 511 in a side view, and has a first arm 512 on the front side and a second arm 513 on the rear side, sandwiching the bent portion 511. The tip end (front end, lower end) of the first arm 512 is fixedly attached to a position near the center in the longitudinal direction of the bridge portion 4, and the tip end (lower end) of the second arm 513 is rotatably connected to the bridge rear end rotation shaft 71.

[0035] The driving device 52 is a driving source for operating the operating arm 51 to tilt the bridge portion 4 relative to the main table 3. The driving device 52 is constituted by, for example, an electric cylinder, and is controlled by a control device (not shown) to perform an extending and retracting operation, thereby rotating the operating arm 51. The driving device 52 has a cylinder tube 521 and a piston rod 522 that can freely advance and retreat with respect to the cylinder tube 521 (in other words, can freely move in and out).

[0036] The driving device 52 is disposed so as to be interposed between the main table 3 and the bent portion 511 of the operation arm 51. The cylinder tube 521 of the driving device 52 is attached to the main table 3 (including the auxiliary table 31) so as to be freely swingable, with the rear end (lower end) being axially supported via a rotating shaft arranged along the left-right direction, in an inclined position with the piston rod 522 side facing upward. The piston rod 522 of the driving device 52 has a tip end (upper end) axially supported via a rotating shaft arranged along the left-right direction by the bent portion 511 of the operation arm 51, and the two are connected so as to be freely rotatable relative to each other.

[0037] For example, when the drive unit 52 contracts from a state in which the longitudinal direction L4 of the bridge portion 4 is aligned horizontally (Figure 3), the bent portion 511 of the operating arm 51 is pulled backward (in other words, retracted), the operating arm 51 rotates around the tip (lower end) of the second arm 513 connected to the bridge rear end rotation shaft 71 as the center of rotation, and the bridge portion 4 to which the tip (front end, lower end) of the first arm 512 is fixed tilts upward relative to the surface of the main table 3 (Figure 4).

[0038] On the other hand, for example, when the drive unit 52 extends from a state in which the longitudinal direction L4 of the bridging portion 4 is aligned horizontally (Figure 3), the bent portion 511 of the operating arm 51 is pushed forward, causing the operating arm 51 to rotate around the tip (lower end) of the second arm 513 connected to the bridge rear end rotation shaft 71 as the center of rotation, and the bridging portion 4 to which the tip (front end, lower end) of the first arm 512 is fixed is tilted downward relative to the plate surface of the main table 3 (Figure 5).

[0039] When the hull rocks vertically due to the influence of waves or the like, the swing operating mechanism 5 controls the extension and contraction of the drive unit 52 to align the relative vertical positional relationship between the access section 6 connected to the front end (tip) of the bridge section 4 and the landing target of the offshore facility, thereby eliminating the difference in elevation between the two.

[0040] A control device (not shown) controls the actuators 22 of the motion compensation mechanism 2 and the drive device 52 of the swing operation mechanism 5 in response to the motion of the hull caused by the effects of waves and the like, thereby providing a mechanism for maintaining the main table 3 horizontal while maintaining the height of the access part 6 connected to the front end (tip) of the bridge part 4 at an appropriate position relative to the landing target of the offshore facility. Note that the height of the access part 6 is adjusted by the swing operation mechanism 5 while the main table 3 is mainly maintained horizontal by the motion compensation mechanism 2.

[0041] The posture of the main table 3 is controlled, for example, by using a gyro sensor to detect the swaying (particularly, tilt) of the hull due to the influence of waves, etc., and the control device operates the sway correction mechanism 2 to correct the swaying (particularly, tilt) of the hull based on the signal output from the gyro sensor, thereby maintaining the main table 3 horizontal.

[0042] The degree of inclination of the bridge section 4 (and thus the height of the access section 6) is controlled, for example, by using a non-contact sensing mechanism to detect the swaying (particularly, up and down movement) of the hull due to the influence of waves, etc., and the control device operates the sway operating mechanism 5 to correct the swaying (particularly, up and down movement) of the hull based on the signal output from the non-contact sensing mechanism, thereby maintaining the height of the access section 6 at an appropriate position relative to the landing target of the offshore facility.

[0043] The mechanism for performing non-contact sensing is configured as a mechanism including a camera, a millimeter wave radar, or a Lidar (short for Light detection and ranging) (not shown) as a non-contact sensor, which is installed on the main table 3, for example.

[0044] The non-contact sensing mechanism is configured to use the non-contact sensor to sense the shape of a target marker of a specific shape installed on the offshore facility or a specific part of a structure or equipment on the offshore facility, measure the relative vertical positional relationship between the landing target of the offshore facility, and function in cooperation with the control device to maintain the height of the access section 6 connected to the front end (tip) of the bridge section 4 at an appropriate position relative to the landing target of the offshore facility (in other words, to maintain the elevation difference between the access section 6 and the landing target within an appropriate range).

[0045] Furthermore, by installing the non-contact sensor on the main table 3, errors in the measurement values ​​caused by the rolling of the ship's hull can be prevented.

[0046] The control device intends to maintain the height of the access section 6 relative to the landing target of the offshore facility at an appropriate position, for example, by repeatedly performing the following process at predetermined time intervals. 1) The elevation difference between the landing target of the offshore facility and the access section 6 measured by the non-contact sensor is compared with a predetermined allowable range for said elevation difference. 2) If the elevation difference measured in 1) above is outside the above-mentioned allowable range, the operation of the swing operation mechanism 5 is calculated so that the elevation difference falls within the above-mentioned allowable range. 3) Based on the result of the calculation in 2) above, a drive instruction signal is output to the drive device 52 of the swing operation mechanism 5.

[0047] The driving device 52 then performs an extension / retraction operation in accordance with the drive instruction signal, causing the bridge portion 4 to tilt upward / downward, thereby adjusting the height of the access portion 6 relative to the landing target of the offshore facility.

[0048] The upper and lower limits specifying the above-mentioned acceptable range for elevation difference are not limited to specific values, but are set appropriately based on various conditions, such as the shape and structure of the ship, the structure of the landing target of the offshore facility, and wave conditions.

[0049] The horizontal positional relationship (specifically, the distance in the front-back direction and the distance in the left-right direction) between the landing target of the offshore facility and the access part 6 may be adjusted by the sway compensation mechanism 2 that operates / controls the attitude of the main table 3. In this case, for example, a drive instruction signal may be output to the sway compensation mechanism 2 based on the measurement result by the non-contact sensor, and each of the six-axis actuators 22 may expand and contract to move the main table 3 in the front-back direction and the left-right direction, thereby adjusting the horizontal positional relationship between the landing target of the offshore facility and the access part 6.

[0050] Here, for example, when a ship on which the bridge device 1 is installed on the forward deck moves to a landing target of an offshore facility, the ship usually moves forward and presses its bow against the landing target or structures and equipment (e.g., boat bumpers) around the landing target so that the distance between the ship and the landing target does not change. However, if the ship's hull is instantaneously and irregularly swayed by irregular and sudden waves and the bow moves away from the landing target or structures and equipment (referred to as "landing target or offshore equipment") around the landing target, the access part 6 may leave the landing target, creating a gap between the access part 6 and the landing target, which may cause a worker to lose his footing or even fall, or the access part 6 may collide after leaving the landing target.

[0051] Furthermore, even if the ship is moving forward and the bow remains pressed against the landing target or offshore facility, when the bridge section 4 tilts upward / downward relative to the surface of the main table 3, the access section 6 moves on an arc with the bridge rear end rotation axis 71 as the center of rotation, so that the fore-and-aft distance between the access section 6 and the landing target changes, which may result in a gap being created between the access section 6 and the landing target, or the access section 6 may hit the landing target (or in other words, get stuck), preventing the bridge section 4 from tilting upward / downward.

[0052] Therefore, the bridging device 1 according to the first embodiment includes a bridging section 4 having one end supported by a shaft and tilting upward and downward, a parallel link 77 arranged parallel to the longitudinal direction L4 of the bridging section 4 and having one end on the same side as the one end of the bridging section 4 supported by a shaft and tilting upward and downward while remaining parallel to the longitudinal direction L4 of the bridging section 4, and a parallel link 77 rotatably connected to the other end of the bridging section 4 and rotatably connected to the other end of the parallel link 77, so that the inclination angle with respect to the horizontal direction is kept constant when the bridging section 4 and the parallel link 77 tilt. The link has a front end connecting post 75 and an access part 6 which is connected to the other end of the bridging part 4 so as to be able to tilt freely relative to each other and whose angle of tilt relative to the link front end connecting post 75 is fixed at a predetermined angle. The access part 6 has a fixed stage 61 connected to the other end of the bridging part 4, a movable stage 62 which can move in the forward and backward directions relative to the fixed stage 61, and a biasing means interposed between the fixed stage 61 and the movable stage 62 for biasing the movable stage 62 forward so as to protrude forward from the fixed stage 61.

[0053] The access section 6 has a flat stage for workers to stand on and is connected to the front end (in other words, the tip) of the bridge section 4. It also has the ability to expand and contract in the fore-and-aft direction, and is a mechanism that is positioned between the bridge section 4 and the landing target of the offshore facility to make it easier for workers to transfer to the landing target.

[0054] The access unit 6 has a fixed stage 61 formed in a generally rectangular flat plate shape in a plan view, a movable stage 62 formed in a generally rectangular flat plate shape in a plan view and disposed on the upper surface side of the fixed stage 61, and rails 63 interposed between the fixed stage 61 and the movable stage 62 for moving the movable stage 62 in the front-rear direction relative to the fixed stage 61. Fixed part handrails 64 are attached to the left and right edges of the upper surface of the fixed stage 61, respectively, and movable part handrails 65 are attached to the left and right edges of the upper surface of the movable stage 62, respectively.

[0055] In the example shown in the figures, a pair of left and right rails 63, 63 are provided at the left and right ends of the fixed stage 61 and the movable stage 62, respectively, and are parallel to each other along the front-to-rear direction so as to be interposed between the fixed stage 61 and the movable stage 62 (see Figures 7, 8, and 9).

[0056] The fixed stage 61 has an end portion on the bridge section 4 side (i.e., a rear end portion) supported by a bridge front end rotation shaft 72 arranged along the left-right direction and rotatably connected to the front end portion of the bridge section 4. In this way, the fixed stage 61 is attached to the bridge section 4 so as to be capable of tilting relative to the plate surface of the bridge section 4 with the bridge front end rotation shaft 72 as the center of rotation.

[0057] The movable stage 62 is configured to be able to extend forward from a position where it overlaps with the fixed stage 61 in the vertical direction relative to the fixed stage 61, or to be retracted to a position where it overlaps with the fixed stage 61 in the vertical direction, by a pair of left and right rails 63, 63 that are provided at each of the left and right ends so as to be interposed between the fixed stage 61 and the movable stage 62, each running in the front-to-back direction. In other words, the movable stage 62 is configured to be able to move forward and backward freely relative to the fixed stage 61.

[0058] The fixed stage 61 and the moving stage 62 are not limited to a specific dimension, and are appropriately set to an appropriate dimension, taking into consideration, for example, the structure of the bridge section 4 and the landing target of the offshore facility. The front-rear dimension of the fixed stage 61 and the moving stage 62 can be set to, for example, about 80 to 120 cm, as just one example.

[0059] The amount of movement (in other words, the amount of displacement, stroke) of the moving stage 62 in the forward and backward directions relative to the fixed stage 61 is not limited to a specific value, but is appropriately set to an appropriate value taking into consideration, for example, the structures of the access part 6 and the landing target of the offshore facility. As merely one example, the amount of movement of the moving stage 62 in the forward and backward directions relative to the fixed stage 61 can be set to, for example, about 60 to 100 cm.

[0060] In order to prevent the access part 6 from being damaged when it comes into contact with the landing target or the offshore facility, and to ensure sliding properties when the access part 6 and the landing target or the offshore facility move relatively in the up-down direction while in contact with each other, a resin cushion member 621 and rollers 622 whose rotation axes are arranged in the left-right direction are provided at the front end of the moving stage 62 (see FIG. 6). Note that only one of the cushion member 621 and the rollers 622 may be provided.

[0061] The movable stage 62 is biased forward so as to extend forward from the fixed stage 61 by a biasing means (not shown) interposed between the fixed stage 61 and the movable stage 62, so that the movable stage 62 is pressed against a landing target of the offshore facility, such as a vertical ladder.

[0062] The biasing means for biasing the fixed stage 61 forward is not limited to a specific mechanism, and an appropriate mechanism is appropriately selected while taking into consideration the fact that when the hull of the vessel moves due to the influence of waves or the like, changing the fore-and-aft distance between the landing target of the offshore facility and the access section 6, the mobile stage 62 can be biased to an extent that prevents the mobile stage 62 from coming off the landing target, and the mobile stage 62 can be pressed against the landing target.

[0063] As the biasing means, specifically, for example, a pneumatic actuator such as a pneumatic cylinder, an electric actuator such as an electric cylinder, or a spring such as a compression coil spring can be used.

[0064] When an actuator is used as the biasing means, a switch may be provided for an operator to operate in order to control the start of operation of the actuator, or a non-contact sensor such as a pressure sensor or an ultrasonic sensor may be provided at the tip of the movable stage 62 of the access section 6 (specifically, for example, the cushion member 621 attached to the front end of the movable stage 62).

[0065] Then, for example, with the initial state being that the mobile stage 62 is located at an intermediate position (referred to as the "central position") between the position of the mobile stage 62 shown in Figure 3 and the position of the mobile stage 62 shown in Figure 7, when the tip of the mobile stage 62 of the access unit 6 approaches a vertical ladder or the like serving as a landing target for the offshore facility, an operator operates a switch, causing the actuator to start operating and the mobile stage 62 to begin to be biased forward so that it extends forward from the fixed stage 61, or when the tip of the mobile stage 62 of the access unit 6 comes into contact with or approaches a vertical ladder or the like serving as a landing target for the offshore facility, the actuator starts operating based on a signal output from a pressure sensor or a non-contact sensor, causing the mobile stage 62 to begin to be biased forward so that it extends forward from the fixed stage 61.

[0066] When the hull sways due to the influence of waves or the like, and the distance in the fore-and-aft direction between the access part 6 and the landing target of the offshore facility becomes longer, the mobile stage 62 moves forward so as to jut out forward from the fixed stage 61, and is pressed against the landing target of the offshore facility. This prevents the access part 6 from separating from the landing target of the offshore facility, creating a gap between the access part 6 and the landing target, and causing a worker to lose his footing or even fall.

[0067] In addition, when the hull sways due to the influence of waves or the like and the fore-and-aft distance between the access section 6 and the landing target of the offshore facility becomes shorter, the movable stage 62 moves backward so as to be pulled toward the fixed stage 61, thereby preventing excessive load from being applied to the bridging device 1.

[0068] On the other hand, when a spring is used as the biasing means, for example, the initial state is one in which the moving stage 62 is in the position shown in Figure 7, and the position of the access part 6 is adjusted by adjusting the position of the ship or by adjusting the position of the main table 3 (and thus the position of the bridge part 4) using the sway correction mechanism 2 so that the tip of the moving stage 62 of the access part 6 comes into contact with a vertical ladder or the like as a landing target for the offshore facility.

[0069] Then, in response to changes in the fore-and-aft distance between the access part 6 and the landing target of the offshore facility caused by the hull rocking due to the effects of waves, etc., the mobile stage 62 moves forward and backward relative to the fixed stage 61, maintaining a state in which it is pressed against the landing target of the offshore facility. This prevents the access part 6 from detaching from the landing target of the offshore facility, creating a gap between the access part 6 and the landing target which could cause a worker to lose his footing or even fall, and also prevents excessive load from being applied to the bridging device 1.

[0070] Shock absorbing means may be provided to prevent excessive load from acting on the biasing means (not shown) provided between the fixed stage 61 and the moving stage 62, thereby preventing damage to the biasing means. Specifically, for example, in order to mitigate the impact when the moving stage 62 suddenly collides with a landing target of the offshore facility or with offshore facilities, shock absorbing means including a shock absorber / damper such as a cylindrical type may be provided between the fixed stage 61 and the biasing means to absorb the backward load acting on the biasing means due to an external force acting on the moving stage 62 when the moving stage 62 collides.

[0071] Also, a stroke sensor such as a linear displacement sensor that measures the degree of movement / displacement of the movable stage 62 relative to the fixed stage 61 (in other words, the amount of expansion and contraction of the access part 6) may be provided. Then, based on the measurement result of the movement / displacement of the movable stage 62 relative to the fixed stage 61 by the stroke sensor, when the forward movement / displacement of the movable stage 62 approaches or reaches the maximum possible forward movement or when the backward movement / displacement of the movable stage 62 approaches or reaches the maximum possible backward movement, an operator may be notified by, for example, turning on a light or sounding an alarm from a speaker.

[0072] A pressure sensor may be provided on the tip of the moving stage 62 of the access unit 6 (specifically, for example, the cushion member 621 attached to the front end of the moving stage 62). Based on the detection result of the contact force of the tip of the moving stage 62 against the landing target of the offshore facility by the pressure sensor, for example, a light may be turned on in red or an alarm may be sounded from a speaker when the tip of the moving stage 62 is not in contact with the landing target of the offshore facility (in other words, not pressed against it), and a light may be turned on in blue or a safety sound may be sounded from a speaker when the tip of the moving stage 62 is in contact with the landing target of the offshore facility (in other words, pressed against it).

[0073] The link mechanism 7 is a mechanism for realizing a four-joint parallel link and controlling the inclination of the access part 6 with respect to the bridge part 4 to keep the postures of the fixed stage 61 and the movable stage 62 (these two stages are also collectively referred to as "stages 61, 62") constant. That is, in the first embodiment, the link mechanism 7 functions as an inclination control mechanism that controls the inclination of the access part 6 with respect to the bridge part 4 to keep the angle of the access part 6 with respect to the horizontal direction constant.

[0074] The link mechanism 7 has a bridge rear end rotating shaft 71 , a bridge front end rotating shaft 72 , a link rear end connecting pillar 73 , a link rear end rotating shaft 74 , a link front end connecting pillar 75 , a link front end rotating shaft 76 , and a parallel link 77 .

[0075] The link rear end connecting posts 73 are provided to stand perpendicularly to the upper surface of the main table 3. In the example shown in the figures, a pair of left and right link rear end connecting posts 73, 73 are disposed facing each other and spaced apart in the left-right direction by a distance wider than the left-right width of the bridge portion 4, at a position near the front end of the main table 3 (see particularly Figures 1, 2, 8, and 9).

[0076] A link rear end rotation shaft 74 is provided at the upper end of each of the pair of left and right link rear end connecting posts 73, 73, and is arranged along the left-right direction.

[0077] The link front end connecting post 75 has a lower end supported by a bridge front end rotating shaft 72 disposed at the front end of the bridge part 4, and is rotatably connected to the front end of the bridge part 4. In the example shown in the figures, a pair of left and right link front end connecting posts 75, 75 are disposed facing each other while being spaced apart in the left-right direction by a distance wider than the left-right width of the bridge part 4 (see particularly Figures 1, 2, 6, 8, and 9).

[0078] A link front end rotation shaft 76 is provided at the upper end of each of the pair of left and right link front end connecting posts 75, 75, and is arranged along the left-right direction.

[0079] The parallel link 77 is in the longitudinal direction / axial direction L 77 is a link that is arranged parallel to the longitudinal direction L4 of the bridging portion 4 and swings upward and downward (in other words, tilts) relative to the main table 3, and constitutes a set of parallel links in combination with the bridging portion 4. In the example shown in the figure, a pair of left and right parallel links 77, 77 are arranged opposite each other above the bridging portion 4, spaced apart in the left-right direction by a distance wider than the left-right width of the bridging portion 4 (see particularly Figures 1, 2, 6, 8, and 9).

[0080] The ends (i.e., rear ends) of each of the pair of left and right parallel links 77, 77 on the main table 3 side are axially supported via a link rear end rotating shaft 74 provided at the upper end of the link rear end connecting column 73, and are rotatably connected to the link rear end connecting column 73.

[0081] In addition, the ends (i.e., front ends) of each of the pair of left and right parallel links 77, 77 on the access section 6 side are axially supported via a link front end rotating shaft 76 provided at the upper end of the link front end connecting column 75, and are mutually rotatably connected to the link front end connecting column 75.

[0082] Here, the distance in a side view from the rotation axis center of the bridge rear end rotating shaft 71 related to the bridge portion 4 to the rotation axis center of the bridge front end rotating shaft 72 and the distance in a side view from the rotation axis center of the link rear end rotating shaft 74 related to the parallel link 77 to the rotation axis center of the link front end rotating shaft 76 are set to the same dimension.

[0083] In addition, the distance from the rotation axis center of the bridge rear end rotating shaft 71 to the rotation axis center of the link rear end rotating shaft 74 in a side view and the distance from the rotation axis center of the bridge front end rotating shaft 72 to the rotation axis center of the link front end rotating shaft 76 in a side view are set to the same dimension.

[0084] That is, the bridge rear end rotating shaft 71, the bridge front end rotating shaft 72, the link rear end rotating shaft 74, and the link front end rotating shaft 76 function as each joint (rotation shaft) of the four-joint parallel link. The bridge portion 4 and the parallel link 77 form a set of parallel links, and the link rear end connecting post 73 and the link front end connecting post 75 form a set of parallel links.

[0085] As a result, the bridge portion 4 and the parallel link 77 are aligned in the longitudinal direction L4 and the longitudinal direction / axial direction L 77 When the bridge portion 4 and the parallel link 77 tilt while remaining parallel to each other, the longitudinal direction / axial direction L of the link front end connecting column 75 changes. 75 is the longitudinal direction / axial direction L of the link rear end connecting column 73 73 is maintained parallel to

[0086] The access portion 6 is configured so as to be mutually inclined with respect to the plate surface of the bridge portion 4, while the angle of inclination with respect to the link front end connecting post 75 is fixed at a predetermined angle.

[0087] In the example shown in the figure, the inclined fixing part 8 is attached to span between the upper end of the link front end connecting column 75 and a position near the front end of the fixed stage 61 of the access part 6, and the access part 6 is in the longitudinal direction / axial direction L of the link front end connecting column 75. 75The fixed stage 61 and the movable stage 62 are fixed in a position in which their plate surfaces are perpendicular to the substrate 1 (see, for example, FIGS. 1, 2, and 3).

[0088] In the example shown in the figure, the link rear end connecting column 73 is provided to stand vertically with respect to the upper surface of the main table 3, and the link front end connecting column 75 is maintained in a state of being parallel to the link rear end connecting column 73. Furthermore, the access section 6 is provided with an inclined fixing section 8 so as to be inclined in the longitudinal direction / axial direction L of the link front end connecting column 75. 75 Since the plate surfaces of the stages 61, 62 are fixed in a vertical position relative to the access section 6, the plate surfaces of the stages 61, 62 of the access section 6 are always maintained horizontal when the bridge section 4 and the parallel link 77 tilt (see Figures 3, 4, and 5).

[0089] Furthermore, by changing the length dimension of the inclined fixing part 8, by changing the fixing position of the upper end of the inclined fixing part 8 relative to the link front end connecting column 75, or by changing the fixing position of the lower end of the inclined fixing part 8 relative to the fixed stage 61 of the access part 6, or by changing the offset amount in the fore-and-aft direction of the link rear end rotating shaft 74 relative to the bridge rear end rotating shaft 71 in a side view, the angle of inclination of the plate surfaces of the stages 61, 62 of the access part 6 can be adjusted and changed to any angle.

[0090] The inclined fixing portion 8 may be formed from a rigid material so as not to deform or expand or contract, or it may be formed from a material which deforms and expands to an extent that the stages 61, 62 of the access portion 6 do not incline significantly when a worker is on board, but which can absorb some of the impact on the stages 61, 62 when the access portion 6 comes into contact with a landing target or offshore equipment.

[0091] 1 and the like, and may be any member or structure that can fix the angle of inclination of the access part 6 relative to the link front end connecting post 75 at a predetermined angle. The inclination fixing part 8 may be, for example, a member that is formed in a triangle when viewed from the side and has an edge of one of its three sides fixed to the link front end connecting post 75 and an edge of the other side fixed to the fixed stage 61 of the access part 6, thereby fixing the angle of inclination of the access part 6 relative to the link front end connecting post 75 at a predetermined angle.

[0092] Next, the operation of the bridging device 1 of the first embodiment having the above-mentioned configuration will be described.

[0093] For example, when the bridging portion 4 tilts upward around the bridge rear end rotation shaft 71 from a state in which the longitudinal direction L4 of the bridging portion 4 is aligned with the horizontal direction (FIG. 3), the link front end connecting pillar 75 connected to the front end of the bridging portion 4 moves upward, and the parallel link 77 connected to the upper end of the link front end connecting pillar 75 also tilts upward (FIG. 4). Also, when the bridging portion 4 tilts downward around the bridge rear end rotation shaft 71 from a state in which the longitudinal direction L4 of the bridging portion 4 is aligned with the horizontal direction (FIG. 3), the link front end connecting pillar 75 connected to the front end of the bridging portion 4 moves downward, and the parallel link 77 connected to the upper end of the link front end connecting pillar 75 also tilts downward (FIG. 5).

[0094] When the bridge section 4 and the parallel link 77 tilt, the bridge rear end rotation shaft 71, the bridge front end rotation shaft 72, the link rear end rotation shaft 74, and the link front end rotation shaft 76 function as each joint (rotation shaft) of the four-joint parallel link, and the bridge section 4 and the parallel link 77 tilt while remaining parallel to each other, and with this configuration, the link front end connecting column 75 maintains a state parallel to the link rear end connecting column 73 regardless of the inclination angle of the bridge section 4, that is, the degree of inclination of the link front end connecting column 75 (in other words, the inclination angle with respect to the horizontal direction) does not change, and therefore the stages 61 and 62 of the access section 6 are always maintained in a constant posture (see Figures 3, 4, and 5). Therefore, regardless of the inclination angle of the bridge section 4, the degree of inclination of the stages 61 and 62 of the access section 6 does not change, and the foothold of the worker who is about to move from the access section 6 to the landing target of the offshore facility is stabilized.

[0095] Furthermore, for example, when the longitudinal distance between the access part 6 and the landing target of the offshore facility becomes long due to the motion of the vessel caused by irregular and sudden waves, the mobile stage 62 moves forward so as to protrude forward from the fixed stage 61 (FIGS. 7, 8, and 9). This prevents a gap from occurring between the access part 6 and the landing target of the offshore facility, and ensures a foothold for workers attempting to move from the access part 6 to the landing target.

[0096] In addition, for example, when the longitudinal distance between the access part 6 and the landing target of the offshore facility becomes shorter due to the motion of the ship caused by irregular and sudden waves, the mobile stage 62 moves backward so as to be pulled toward the fixed stage 61 (FIG. 3). This prevents excessive load from acting on the bridge device 1, prevents damage to the bridge device 1, and maintains its soundness, thereby ensuring the safety of workers attempting to move from the access part 6 to the landing target.

[0097] According to the bridging device 1 of embodiment 1, the access section 6 has a fixed stage 61 connected to the other end of the bridging section 4, a movable stage 62 movable in the fore-and-aft direction relative to the fixed stage 61, and a biasing means interposed between the fixed stage 61 and the movable stage 62 and biasing the movable stage 62 forward so that it protrudes forward from the fixed stage 61. Therefore, when the hull is instantaneously and irregularly rocked due to irregular and sudden waves and the fore-and-aft distance between the access section 6 and the landing target of the offshore facility changes, the movable stage 62 can move forward and backward relative to the fixed stage 61 in accordance with the change in the fore-and-aft distance, thereby maintaining a state in which it is pressed against the landing target. This makes it possible to prevent a situation in which the access section 6 separates from the landing target and a gap is created between the movable stage 62 and the landing target, causing a worker to lose his footing or even fall, thereby ensuring the safety of transferring to the landing target, and also makes it possible to prevent a situation in which the access section 6 hits (or, gets stuck on) the landing target and the bridging section 4 cannot tilt upward / downward.

[0098] According to the bridging device 1 of embodiment 1, the angle of inclination of the access section 6 relative to the link front end connecting column 75, which maintains a constant angle of inclination relative to the horizontal direction when the bridging section 4 and the parallel link 77 tilt, is fixed at a predetermined angle. Therefore, when the bridging section 4 and the parallel link 77 tilt, the stages 61, 62 of the access section 6 can always be maintained in a constant posture and the plate surfaces of the stages 61, 62 can always be maintained in a horizontal state, for example. This makes it possible to prevent the stages 61, 62 of the access section 6 from tilting, causing the worker to lose balance, fall, or lean forward and collide with the landing target, or even fall, thereby ensuring the safety of the worker when transferring to the landing target.

[0099] According to the bridging device 1 of embodiment 1, furthermore, since it has an impact absorbing means for absorbing the backward load acting on the urging means, it is possible to prevent excessive load from acting on the urging means provided between the fixed stage 61 and the movable stage 62, thereby preventing damage to the urging means, and in turn, it is possible to maintain the integrity of the bridging device 1 and ensure the safety of workers attempting to transfer from the access section 6 to the landing target.

[0100] According to the bridging device 1 of embodiment 1, furthermore, since a cushion member 621 and a roller 622 are provided at the front end of the moving stage 62, it is possible to prevent the access part 6 from being damaged when it comes into contact with the landing target or the offshore facility, and it is possible to ensure the sliding properties when the access part 6 and the landing target or the offshore facility move relative to each other in the vertical direction while in contact with each other, thereby preventing damage to each of them. In turn, it is possible to maintain the integrity of the bridging device 1 and ensure the safety of workers attempting to transfer from the access part 6 to the landing target.

[0101] According to the bridging device 1 of embodiment 1, furthermore, since it is provided with lights and speakers that operate according to the amount of movement of the movable stage 62 in the forward and backward directions, it is possible to inform the worker that there is no room for movement of the movable stage 62 or that the amount of movement has reached its maximum, making it possible to more reliably ensure the safety of the worker.

[0102] The bridging device 1 of embodiment 1 is also provided with lights and speakers that operate in conjunction with whether or not the tip of the moving stage 62 is in contact with the target equipment, so that the worker can be informed of whether or not the tip of the moving stage 62 is in contact with the target equipment, making it possible to more reliably ensure the safety of the worker.

[0103] (Embodiment 2) FIG. 10 is a side view showing an overall structure of a bridging device 1A according to a second embodiment of the present invention.

[0104] This embodiment 2 differs from the above-described embodiment 1 in that it does not have the link rear end connecting post 73, link rear end rotating shaft 74, link front end connecting post 75, link front end rotating shaft 76, and parallel link 77 that constitute the link mechanism 7, nor the tilt fixed part 8, but does have a tilt control mechanism 9A. However, the other configurations are equivalent to those of embodiment 1 above, and therefore the same symbols are used for the configurations equivalent to those of embodiment 1 above, and their description will be omitted.

[0105] In the second embodiment, a tilt control mechanism 9A is provided between the bridge portion 4 and the access portion 6 as a mechanism for controlling the tilt of the access portion 6 relative to the bridge portion 4 in place of the link mechanism 7 to keep the posture of the stages 61, 62 constant (in other words, the angle of the access portion 6 relative to the horizontal direction). The tilt control mechanism 9A has an expandable actuator 91 and a connecting link 92.

[0106] The telescopic actuator 91 is a drive source for tilting the access portion 6 relative to the plate surface of the bridging portion 4 via a connecting link 92. The telescopic actuator 91 has a cylinder tube 911 and a piston rod 912 that can freely advance and retreat relative to the cylinder tube 911 (in other words, can freely move in and out).

[0107] The telescopic actuator 91 is disposed so that its axial direction is along the longitudinal direction L4 of the bridging portion 4, and the cylinder tube 911 is fixed to a position near the front end (in other words, the tip) of the lower surface of the bridging portion 4, and the piston rod 912 is attached so as to telescope in front of the cylinder tube 911 (i.e., in the space on the access portion 6 side). In other words, the telescopic actuator 91 is provided so that its telescopic direction is along the longitudinal direction L4 of the bridging portion 4.

[0108] The connecting link 92 is provided between the telescopic actuator 91 and the access portion 6 to connect the telescopic actuator 91 and the access portion 6 .

[0109] Specifically, the connecting link 92 is a link member that connects the piston rod 912 and the fixed stage 61; its rear end is connected to the tip end (in other words, the front end) of the piston rod 912 of the telescopic actuator 91 via a connecting shaft so that they can rotate freely relative to each other, and its front end is axially supported via a rotating shaft at a midpoint in the fore-aft direction on the underside of the fixed stage 61 of the access section 6 so that it can swing freely.

[0110] The extension and retraction movement of the extension actuator 91 is controlled by a control device (not shown) which controls the extension and retraction movement of the drive unit 52, which is the driving source for operating the operating arm 51 to tilt the bridging portion 4 relative to the main table 3, so as to keep the posture of the stages 61, 62 of the access portion 6 constant in response to the tilting movement of the bridging portion 4.

[0111] For example, when the longitudinal direction L4 of the bridging portion 4 is aligned horizontally (Figure 10), and the drive unit 52 contracts under the control of a control device (not shown), the operating arm 51 rotates, and the bridging portion 4 tilts upward relative to the surface of the main table 3, the telescopic actuator 91 contracts appropriately under control of the control device corresponding to the contraction of the drive unit 52, so that the surface of the stages 61, 62 of the access portion 6 is always maintained in a horizontal state (see Figure 11).

[0112] In addition, the plate surfaces of the stages 61, 62 of the access section 6 are not limited to being maintained in a horizontal state, but may be maintained in a state inclined at any predetermined angle by giving in advance to a control device (not shown) the degree of deviation from the horizontal (in other words, the degree of inclination).

[0113] According to the bridging device 1A of the second embodiment, the same action and effect as the bridging device 1 of the first embodiment described above can be obtained. In particular, the telescopic actuator 91 is adapted to appropriately telescopically operate in response to the tilting operation of the bridging section 4, thereby causing the access section 6 to tilt relative to the bridging section 4. Therefore, when the bridging section 4 tilts, the stages 61, 62 of the access section 6 can always be kept in a constant posture, and the plate surfaces of the stages 61, 62 can always be kept horizontal, for example. This makes it possible to prevent the stages 61, 62 of the access section 6 from tilting, causing the worker to lose balance, fall, or lean forward and collide with the landing target, or even fall, thereby ensuring the safety of the worker when transferring to the landing target.

[0114] (Embodiment 3) FIG. 12 is a side view showing an overall structure of a bridging device 1B according to a third embodiment of the present invention.

[0115] This embodiment 3 differs from the above-described embodiment 1 in that it does not have the link rear end connecting post 73, link rear end rotating shaft 74, link front end connecting post 75, link front end rotating shaft 76, and parallel link 77 that constitute the link mechanism 7, nor the tilt fixed part 8, but does have a tilt control mechanism 9B. However, the other configurations are the same as those of embodiment 1 above, and therefore the same symbols are used for the configurations that are the same as those of embodiment 1 above, and their explanations will be omitted.

[0116] In the third embodiment, a tilt control mechanism 9B is provided between the bridge portion 4 and the access portion 6 as a mechanism for controlling the tilt of the access portion 6 relative to the bridge portion 4 in place of the link mechanism 7 to keep the posture of the stages 61, 62 constant (in other words, the angle of the access portion 6 relative to the horizontal direction). The tilt control mechanism 9B has a telescopic actuator 93, a first link 94, and a second link 95.

[0117] The telescopic actuator 93 is a drive source for tilting the access portion 6 relative to the plate surface of the bridging portion 4 via a first link 94 and a second link 95. The telescopic actuator 93 has a cylinder tube 931 and a piston rod 932 that can move forward and backward relative to the cylinder tube 931 (in other words, can move in and out).

[0118] The telescopic actuator 93 is inclined with the piston rod 932 side facing upward, and the rear end (lower end) of the cylinder tube 931 is axially supported via a rotating shaft 96 at a position near the front end (in other words, the tip) of the side of the bridge portion 4 so that it can swing freely.

[0119] The first link 94 and the second link 95 are provided between the telescopic actuator 93 and the access portion 6 to connect the telescopic actuator 93 and the access portion 6 .

[0120] The first link 94 is a link member that connects the piston rod 932 and the fixed stage 61; its rear / upper end is connected to the tip end (in other words, the front end) of the piston rod 932 of the telescopic actuator 93 via a connecting shaft 97 so as to be freely rotatable relative to each other, and its front / lower end is attached to the side of the fixed stage 61 of the access section 6 at a midpoint in the fore-and-aft direction via a connecting shaft.

[0121] The second link 95 has an upper end connected to the tip end (in other words, the front end) of the piston rod 932 of the telescopic actuator 93 via a connecting shaft 97 so as to be freely rotatable relative to each other, and a lower end connected to the bridge front end rotating shaft 72.

[0122] The telescopic actuator 93 and the first link 94 are arranged in a mountain shape (in other words, an upside-down V shape) with the connecting shaft 97, which is the connecting part, as the apex in a side view. Also, the first link 94 and the second link 95 are arranged in a mountain shape (in other words, an upside-down V shape) with the connecting shaft 97, which is the connecting part, as the apex in a side view.

[0123] The extension and retraction movement of the extension actuator 93 is controlled by a control device (not shown) which controls the extension and retraction movement of the drive unit 52, which is the driving source for operating the operating arm 51 to tilt the bridging portion 4 relative to the main table 3, so as to keep the posture of the stages 61, 62 of the access portion 6 constant in response to the tilting movement of the bridging portion 4.

[0124] For example, when the longitudinal direction L4 of the bridging portion 4 is aligned horizontally (Figure 12), and the drive unit 52 contracts under the control of a control device (not shown), the operating arm 51 rotates, and the bridging portion 4 tilts upward relative to the plate surface of the main table 3, the telescopic actuator 93 extends appropriately under control of the control device corresponding to the contraction movement of the drive unit 52, so that the plate surfaces of the stages 61, 62 of the access portion 6 are always maintained in a horizontal state (see Figure 13).

[0125] In addition, the plate surfaces of the stages 61, 62 of the access section 6 are not limited to being maintained in a horizontal state, but may be maintained in a state inclined at any predetermined angle by giving in advance to a control device (not shown) the degree of deviation from the horizontal (in other words, the degree of inclination).

[0126] According to the bridging device 1B of embodiment 3, the same action and effect as the bridging device 1 of embodiment 1 described above can be obtained, and in particular, the telescopic actuator 93 is adapted to appropriately telescopically operate in response to the tilting operation of the bridging section 4, thereby causing the access section 6 to tilt relative to the bridging section 4. Therefore, when the bridging section 4 tilts, the stages 61, 62 of the access section 6 can always be kept in a constant posture, and the plate surfaces of the stages 61, 62 can always be kept, for example, horizontal. This makes it possible to prevent the stages 61, 62 of the access section 6 from tilting, causing the worker to lose balance, fall, or lean forward and collide with the landing target, or even fall, thereby ensuring the safety of the worker when transferring to the landing target.

[0127] Although the embodiment of the present invention has been described above, the specific configuration is not limited to the above embodiment, and even if there are design changes and the like within the scope of the gist of the present invention, they are included in the present invention.

[0128] For example, in the above embodiment, the technical idea of ​​the bridging device 1 according to the present invention is mainly applied to a bridging device mounted on a ship, but the subject to which the technical idea of ​​the bridging device 1 according to the present invention can be applied is not limited to a bridging device mounted on a ship, and the technical idea of ​​the bridging device 1 according to the present invention can also be applied to, for example, a ladder device of a fire ladder truck and various gangways. Note that, in the above embodiment, the main table 3 is structured so that a person can sit on it, but the main table 3 may be structured as a base to which the bridging section 4 is connected and not so that a person can sit on it.

[0129] In addition, in the above embodiment, an unsteadiness correction mechanism 2 that operates as a six-axis device with six degrees of freedom is used to keep the main table 3 horizontal; however, the mechanism for supporting the main table 3 of the bridging device of this invention is not limited to the six-axis device in the above embodiment, and a two-axis device with two degrees of freedom, a three-axis device with three degrees of freedom, or a simple support leg or support base that does not have the function of keeping the main table 3 horizontal may also be used. [Explanation of symbols]

[0130] 1. Cross-linking device (embodiment 1) 2. Stability correction mechanism 21 Base Frame 22 Actuator 3. Main Table 31 Auxiliary Table 32 Table railing 4 Crosslinked part 41 Bridge handrail 5 Swing operation mechanism 51 Operating arm 511 Bend 512 First Arm 513 Second Arm 52 Drive unit 521 Cylinder tube 522 Piston rod 6 Access section 61 Fixed Stage 62 Moving Stage 621 Cushioning material 622 Laura 63 Rail 64 Fixed handrail 65 Moving Handrail 7 Link mechanism 71 Bridge rear end rotating shaft 72 Bridge front end rotating shaft 73 Link rear end connecting pillar 74 Link rear end rotating shaft 75 Link front end connecting pillar 76 Link front end rotating shaft 77 Parallel link 8 Tilt fixing part 1A Cross-linking device (embodiment 2) 9A Tilt control mechanism (embodiment 2) 91 Telescopic Actuator 911 Cylinder tube 912 Piston rod 92 Links 1B Cross-linking device (Embodiment 3) 9B Tilt control mechanism (third embodiment) 93 Telescopic Actuator 931 Cylinder tube 932 Piston rod 94 First Link 95 Second Link 96 Rotational Axis 97 Connecting shaft

Claims

1. A bridge portion having one end supported by a shaft and capable of tilting upward and downward; an access portion connected to the other end of the bridge portion so as to be mutually inclined; and a tilt control mechanism for controlling the tilt of the access portion with respect to the bridge portion to keep the angle of the access portion with respect to the horizontal direction constant, The access portion is a fixed stage connected to the other end of the bridge portion; a movable stage that is movable in a forward and backward direction relative to the fixed stage; and a biasing means interposed between the fixed stage and the movable stage for biasing the movable stage forward so as to protrude forward from the fixed stage. A cross-linking device comprising:

2. The tilt control mechanism includes: a parallel link arranged parallel to the longitudinal direction of the bridge portion, one end of which is on the same side as the one end of the bridge portion and is supported by a shaft, and which tilts upward and downward while remaining parallel to the longitudinal direction of the bridge portion; a link front end connecting post that is rotatably connected to the other end of the bridge portion and to the other end of the parallel link, so that a tilt angle with respect to the horizontal direction is kept constant when the bridge portion and the parallel link perform a tilting operation, The angle of inclination of the access portion with respect to the link front end connecting pillar is fixed at a predetermined angle.

2. The cross-linking device according to claim 1 .

3. The tilt control mechanism includes: a telescopic actuator including a cylinder tube and a piston rod movable forward and backward relative to the cylinder tube and attached to the bridge portion; a link member connecting the piston rod and the fixed stage, The telescopic actuator performs telescopic motion in response to the tilting motion of the bridge portion, whereby the access portion performs a tilting motion relative to the bridge portion via the link member.

2. The cross-linking device according to claim 1 .

4. The movable stage further includes a shock absorbing means interposed between the fixed stage and the biasing means for absorbing a backward load acting on the biasing means due to an external force acting on the movable stage.

4. A cross-linking device according to claim 1 , wherein the cross-linking device is a bridging device.

5. At least one of a cushion member and a roller is provided at the front end of the moving stage.

5. A cross-linking device according to claim 1 , wherein the cross-linking device is a bridging device.

6. at least one of a light and a speaker that operates when the amount of movement of the movable stage in the forward and backward directions relative to the fixed stage approaches or reaches a maximum amount of movement, 6. A cross-linking device according to claim 1 , wherein the cross-linking device is a bridging device.

7. At least one of a light and a speaker that operates in conjunction with whether or not the tip of the moving stage is in contact with the target facility is provided.

7. A cross-linking device according to claim 1 , wherein the cross-linking device is a bridging device.

Images