JP2012206556A - Elevation-type thruster apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an elevation-type thruster apparatus having a compact elevation device capable of raising a thruster above a waterline surface so as to enable inspection and repair of the thruster even at an offshore operating point.SOLUTION: The elevation-type thruster apparatus includes: a pair of racks 31 of the required height, disposed on outer surfaces of a canister 21 and having teeth portions 32 with a predetermined pitch in the vertical direction; guide members which are provided along the racks 31; and a pair of elevation apparatuses 30 which raise and lower the canister 21 within an elevation path 2. Each of the pair of elevation apparatuses 30 comprises: a pair of catches, upper and lower, which each independently engage and disengage with teeth portions 32 of the rack 31 at positions vertically spaced apart; a pair of frames, upper and lower, equipped with the catches; and an elevation cylinder 33 which is provided between the frames. This elevation cylinder 33, with respect to one frame which is affixed to the elevation path side, raises and lowers the other of the frames as guided by a guide member.

Description

  The present invention relates to an elevating thruster apparatus incorporating a thruster used for holding a fixed point in an excavation ship, a floating production facility, or the like.

  Conventionally, offshore oil and gas field development has been carried out in offshore waters far from land, but in recent years, such undersea oil and gas field development has a tendency to deepen. And, in the case of drilling vessels and floating production equipment used for development in deep water (hereinafter collectively referred to as “excavation vessels”), it is fixed to the ocean floor to excavate several thousand meters of the ocean floor. You can hold a fixed point at sea without having to. As a system for holding such a drilling ship at a fixed point on the sea, an increasing number of systems equipped with a plurality of thrusters so that attitude control can be performed. For example, a drilling ship equipped with a plurality of thrusters can control the thrust of each thruster so that a fixed point can be maintained using, for example, a GPS signal even under stormy weather. For example, in the case of a drilling ship, about 4 to 6 thrusters are provided so that a fixed point can be held.

  However, the thruster may require failure due to aging or accidental maintenance. However, when the excavation ship or the like is in operation, for example, it is necessary to maintain a state where the seabed is excavated by an excavation drill, and the fixed point cannot be left. For this reason, when it becomes necessary to check and repair the thruster, it is necessary to perform underwater removal work of the thruster by a diver, which is difficult. In addition, since the thruster cannot be removed during stormy weather, the repair time is also limited.

  In addition, it is conceivable to move a drilling vessel or the like to a dock on the land to inspect and repair the thruster. However, in this case, a great deal of time and cost are required.

  Therefore, in recent years, there has been proposed an apparatus capable of lifting the thruster upward from the draft surface so that the thruster can be inspected and repaired even at an offshore operating point.

  For example, as a prior art of this type, there is a ship in which a thruster is moved up and down by a rack and pinion drive system or a hydraulic cylinder drive system. As a rack and pinion drive system, a pinion is provided on the thruster side so that the rack on the hull side can be extended upward, and the thruster is pulled up above the draft surface by the pinion along the rack. . Moreover, as a hydraulic cylinder drive system, a raising / lowering cylinder is suspended under a deck, and a raising / lowering body is raised / lowered by this raising / lowering cylinder (for example, refer patent document 1).

  As another prior art, there is one in which a thruster is moved up and down by a hydraulic cylinder drive system or a rack and pinion drive system. This prior art describes a one-step push-up method and a one-step push-up telescope method as the hydraulic cylinder drive method, and the rack and pinion drive method uses a pinion provided on the hull side to unify the thruster side rack. What is raised and lowered in the process and what is raised and lowered by another pinion in the middle of raising and lowering are described. By these, the thruster is raised and lowered between a position below the ship bottom and a position above the deck (for example, see Patent Document 2).

Japanese Patent No. 4526184 JP 2001-55197 A

  However, in the case of Patent Document 1, in order to raise and lower the thruster by the rack and pinion drive method, a very large drive device that can raise and lower a large load is required. In order to make this drive unit compact, it is necessary to use high-strength materials for both the rack and pinion, and since the reduction gear mechanism is a machined finished product, the lifting device is very expensive. Become.

  In the case of the rack and pinion driving method described in Patent Document 2, the lifting device is very expensive as in Patent Document 1.

  In the case of the above-mentioned Patent Document 2, in the one-step push-up hydraulic cylinder system, the required push-up length is pushed up in one step of the hydraulic cylinder, so that the required stroke of the hydraulic cylinder is long and the thruster is large above the draft surface. Since the weight is raised and lowered, it becomes a very large device to have sufficient buckling strength, and becomes very expensive. Furthermore, in the case of a one-step push-up telescope type hydraulic cylinder system, the telescope type rod is expanded and contracted in order to raise and lower the thruster by the required elevation length, so that the configuration of the cylinder becomes complicated and the same as the above hydraulic cylinder In addition, it becomes a very large device for buckling strength measures, and becomes very expensive.

  Further, in the case of the hydraulic cylinder system of Patent Document 1, since the lifting and lowering body of the thruster is lifted and lowered through the ring, the ring surrounding the lifting and lowering body becomes larger when the thruster is enlarged and the lifting and lowering section is enlarged. Therefore, there is a difficulty in dealing with the increase in size of the lifting device.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an elevating type thruster apparatus including a compact elevating apparatus that can raise the thruster up above the draft surface so that the thruster can be inspected and repaired even at an offshore operating point. .

  In order to achieve the above object, the present invention includes a thruster provided so as to protrude downward from a bottom portion, and a canister for moving up and down in a hoistway provided in a hull incorporating a drive device for driving the thruster. An elevating thruster device having at least a pair of racks with a predetermined pitch in the vertical direction and provided in positions in the horizontal direction on the outer surface of the canister, and the vertical direction along each rack. A pair of elevating devices for elevating the canister between the operating position of the thruster and a position above the draft surface in the hoistway along the pair of racks. The lifting device includes a pair of upper and lower catches that are independently fitted to and disengaged from the top and bottom tooth portions of the rack, a pair of upper and lower frames provided with the catches, and the pair of upper and lower A lifting cylinder provided between the frames, and the lifting cylinder is configured to lift and lower the other frame with the guide member as a guide with respect to one frame fixed to the hoistway side. It is characterized by. The “hull” in this specification and the claims refers to an object provided with a lifting and lowering thruster apparatus including a drilling ship and a floating production facility. The “canister” refers to a cylindrical container having a thruster projecting downward and a drive device for driving the thruster.

  With this configuration, one catch is fitted to the rack tooth portion provided in the canister and lifted by the lifting cylinder, and then the other catch is fitted to the rack tooth portion to load the lifting thruster device. Support, release one catch from the tooth part, lower it with the lifting cylinder and fit it to the lower tooth part, then release the other catch from the tooth part and raise one catch with the lifting cylinder, so-called By repeating the scale-worming operation, it can be stably raised by a compact lifting device having a short stroke lifting cylinder. Moreover, it can descend | fall stably by reverse operation | movement. Therefore, with a compact lifting device, the lifting thruster device can be raised and lowered between the operating position and a position above the draft surface. Moreover, since the lifting device is provided independently for each rack with respect to the pair of racks even when the canister cross section is increased by increasing the size of the thruster, the lifting device frame is increased in size. It is possible to cope easily without doing.

  The pair of upper and lower frames may be attached so as to fix a frame positioned below to the hoistway. If comprised in this way, the self-weight of a raising / lowering thruster apparatus can be raised / lowered at the bore side with a large area of the raising / lowering cylinder provided between a pair of upper and lower frames, and the raising / lowering cylinder is used in an optimal design. be able to.

  The hoistway includes a maintenance inspection floor at a position above the draft surface, the canister includes a rack having a required length for raising the thruster to the maintenance inspection floor position, and the elevating device includes the thruster. May be arranged at a required height position of the hoistway so that it can be raised and lowered from the operating position to the maintenance inspection floor position. If comprised in this way, a thruster can be raised / lowered to the maintenance inspection floor position which can be maintained from an operation position, and a maintenance inspection work can be performed by removing a thruster from a canister on a maintenance inspection floor.

  In addition, the pair of upper and lower frames includes a drive cylinder that allows the catch to be fitted and detached independently from the rack at the upper and lower positions, and a guide that allows the catch to be fitted to and detached from the rack teeth by the expansion and contraction of the drive cylinder. May have a part. If comprised in this way, a catch can be stably fitted to the tooth part of a rack from the flame | frame provided in the up-down position of the raising / lowering cylinder with a compact structure.

  In addition, when the thruster is in operation, the elevating cylinder engages the pair of upper and lower catches with the teeth of the rack and applies a force in the reverse direction to the catch to hold the vertical load acting on the canister. It may be configured to. If configured in this way, as a load holding method acting on the canister, the vertical static load acting on the canister is applied to the frame fixedly attached to the hoistway by the reverse force applied to the pair of catches. The dynamic load acting in the opposite direction to the static load due to waves or the like can be held by the catch provided in the moving frame.

  The hoistway includes a fixing portion of the elevating device provided at a plurality of locations separated in the vertical direction, and a load holding device that temporarily holds a load of the elevating thruster device when the fixing portion is changed. And the lifting device may include a fixing means that can be attached to and detached from a fixing portion of the hoistway. If comprised in this way, at the time of raising / lowering of a raising / lowering thruster apparatus, a load holding device is temporarily hold | maintained by the load holding device in the middle of a hoistway, and a fixed part position of an raising / lowering apparatus is changed, and a rack is changed. The lifting distance of the lifting / lowering thruster device can be secured by suppressing the length of the lifting / lowering thruster device.

  The hoistway includes a support guide that supports a horizontal load acting on the canister, and a surrounding plate that reduces the distance between the canister and the hoistway at the entire circumference at the position of the support guide. It may be. If comprised in this way, the water surface fluctuation | variation by the wave of the water surface between a hoistway and a canister can be suppressed.

  Further, a jack that supports the canister in a horizontal direction may be provided between the support guide and the canister. If comprised in this way, the play by the clearance gap between a canister and a hoistway at the time of operation | movement of a thruster can be eliminated easily.

  ADVANTAGE OF THE INVENTION According to this invention, it is possible to provide the raising / lowering thruster apparatus provided with the compact raising / lowering apparatus which can raise / lower so that a thruster can be pulled up above a draft surface in an offshore operation point, and can be inspected and repaired. It becomes.

It is a side view which shows the raising / lowering type thruster apparatus which concerns on one Embodiment of this invention. It is a front view of the raising / lowering thruster apparatus shown in FIG. It is an III-III arrow expanded sectional view shown in FIG. It is an IV-IV arrow expanded sectional view shown in FIG. It is a VV arrow expanded sectional view shown in FIG. FIG. 6 is an enlarged view of a VI part shown in FIG. 5. It is a VII-VII arrow expanded sectional view shown in FIG. It is an enlarged view of the raising / lowering apparatus part shown in FIG. It is IX-IX arrow sectional drawing shown in FIG. It is XX arrow sectional drawing shown in FIG. It is XI-XI arrow sectional drawing shown in FIG. (a) to (i) show the ascending motion with a downward positive load acting on the catch. (a) to (i) show the lowering operation in a state where a downward positive load is applied to the catch. (a) to (i) show the ascending motion with upward load applied to the catch. (a) to (i) show the lowering operation in a state where an upward load is acting on the catch. (a), (b) is a side view which shows the raising operation | movement of the raising / lowering thruster apparatus based on 1st Embodiment. (a), (b) is a side view which shows the raising operation | movement of the raising / lowering thruster apparatus based on 1st Embodiment following FIG. (a), (b) is a side view which shows the raising operation | movement of the raising / lowering thruster apparatus based on 2nd Embodiment. (a), (b) is a side view which shows the raising operation | movement of the raising / lowering thruster apparatus based on 2nd Embodiment following FIG. (a), (b) is a side view which shows the raising operation | movement of the raising / lowering thruster apparatus based on 2nd Embodiment following FIG. (a), (b) is a side view which shows the raising operation | movement of the raising / lowering type thruster apparatus based on 2nd Embodiment following FIG. It is a front view which shows the relationship between the rack and catch which concern on the 1st example of the countermeasure against waves in the raising / lowering thruster apparatus of this invention. It is a front view which shows the relationship between the rack and catch which concern on the 2nd example of the countermeasure against waves in the raising / lowering thruster apparatus of this invention.

  Hereinafter, an example of an embodiment according to the present invention will be described with reference to the drawings. In the following embodiments, an elevating thruster device provided in a ship will be described as an example.

  As shown in FIGS. 1 and 2, the lifting thruster device 20 includes a canister 21 that moves up and down a hoistway 2 provided in the hull 1, and a thruster 22 that protrudes downward from the lower portion of the canister 21. The canister 21 and the hoistway 2 are formed in a rectangular cross section in plan view (FIGS. 4 and 5). Between these canisters 21 and the hoistway 2, predetermined intervals S1 and S2 are provided. The gaps S1 and S2 are larger S2 when a rack 31 described later is provided.

  Inside the canister 21, there are a turning drive unit 23 for turning the thruster 22, a drive motor 25 for rotating the propeller 24, a turning pump unit 26 for supplying driving oil to the turning drive unit 23, and various parts. A lubricating oil pump unit 27 and the like for lubrication are provided.

  A pair of racks 31 are provided on the two outer surfaces of the canister 21 facing each other. The rack 31 is formed with teeth 32 having a constant pitch in the vertical direction, and is continuously provided in the vertical direction of the canister 21. In the drawing, the illustration of the tooth portion 32 at the intermediate portion is omitted. The rack 31 is connected to the opposing racks 31 of the portion protruding outward from the canister 21 by a reinforcing member 31b.

  Further, the hoistway 2 where the canister 21 ascends and descends is provided with a support guide 3 for supporting a horizontal load acting on the canister 21 when the thruster 22 is operated, and a horizontal load support for the canister 21 and a guide when the canister 21 is raised and lowered. A supporting / elevating guide 4 and an elevating guide 5 serving as a guide for elevating the canister 21 are provided. In this example, a support guide 3 is provided at the lowermost part, and support / elevation guides 4 are provided at two upper and lower positions. Further, an elevating guide 5 is provided above the hoistway 2 so as to be positioned above the canister 21 when the thruster 22 is in operation and to serve as a guide when the elevating thruster device 20 is raised and lowered.

  Between the canister 21 and the hoistway 2 of the hull 1, a pair of elevating devices 30 that elevate the thruster 22 by elevating the canister 21 along the hoistway 2 are provided.

  The elevating device 30 is provided at the position of the rack 31 and is provided with elevating cylinders 33 for elevating the canister 21 via the rack 31. The lift cylinder 33 has a lower portion supported on the hoistway 2 side and an upper portion supported on the canister 21 side. The support of the lift cylinder 33 and the lift of the canister 21 by the lift device 30 will be described later.

  As shown in FIG. 3, as a cross section at the upper position of the canister 21, racks 31 provided on the outer surfaces of the two opposing surfaces of the canister 21 protrude outward. The rack 31 is formed with a required length extending in the vertical direction (FIG. 1). The load of the lifting type thruster device 20 is supported on the hull 1 by the lifting device 30 through the rack 31. In this example, the rack 31 is provided on the two opposing surfaces of the canister 21, but the rack 31 may be provided at a diagonal position.

  As shown in FIG. 4, the canister 21 is guided by elevating guides 5 provided at the four corners of the hoistway 2 as a cross section at the lower position of the elevating device 30 above the canister 21. In this embodiment, the load support structure (fixed portion) 9 of the lifting device 30 is provided at this position.

  As shown in FIG. 5, the canister 21 is supported by the support / elevation guide 4 provided at the four corners of the hoistway 2 as a cross section at the position of the support / elevation guide 4 of the canister 21. As shown in FIG. 6, the support / elevation guide 4 includes a support guide portion 4 a that supports a horizontal load acting on the canister 21, and an elevating guide portion 4 b that guides the elevating and lowering guide 4. The raising / lowering guide part 4b is provided in the corner part so that it may be located on the extension line of the said raising / lowering guide 5, and the support guide part 4a is provided in the inner side. A pad 6 (FIGS. 1 and 2) is provided on the canister 21 at a position where the support guide portion 4a abuts. The gap between the support guide portion 4a and the pad 6 is narrow, and the gap between the lifting guide portion 4b and the canister 21 is set a little wider. The gap T between the pad 6 and the support guide portion 4a allows the canister 21 to move up and down, but a small gap T that suppresses the horizontal movement as much as possible (for example, about a few mm: exaggerated in the figure). Set to

  As shown in FIG. 7, the canister 21 is supported in the horizontal direction by the support guides 3 provided at the four corners of the hoistway 2 as a cross section at the lowest position of the canister 21. The support guide 3 is provided so as to be positioned on a downward extension line of the support guide portion 4 a provided in the support / elevation guide 4.

  Further, in this embodiment, as shown in FIG. 7, a surrounding plate 7 is provided on the upper part of the support guide 3 so that the distances S <b> 1 and S <b> 2 from the periphery of the canister 21 are small distances S <b> 3. The surrounding plate 7 is provided so that the space around the canister 21 is a predetermined small interval S3. As will be described later, the water surface between the hoistway 2 and the canister 21 due to the narrowing effect of the interval S3. The fluctuation of the water surface due to the waves is suppressed. In this example, the surrounding plate 7 is provided on the lowermost support guide 3 and the lower one support / lift guide 4 (FIGS. 1 and 2).

  In addition, the said clearance gap T exists between the support guide part 4a of the said support guide 3 and the support and raising / lowering guide 4, and the outer surface of the canister 21 (FIG. 6). Therefore, when the thruster 22 is in operation, the canister 21 moves by the gap T. Therefore, in order to prevent the canister 21 from moving, a jack 8 may be provided near the level of the support guide 3 below the canister 21 during operation (FIG. 1). As the jack 8, for example, it is also provided at the position of the upper support / lift guide 4 (not shown) and provided at two places on each surface, for a total of eight places, stable holding can be achieved.

  Next, as shown in FIG. 8, the elevating device 30 includes a lower frame 34 that supports the lower part of the elevating cylinder 33 on the hoistway 2 side (hereinafter, this lower frame 34 is referred to as a holding catch frame “HC frame 34”). ) And an upper frame 35 (hereinafter, referred to as a working catch frame “WC frame 35”) that is provided above the elevating cylinder 33 and moves up and down. The WC frame 35 is supported on the canister 21 side. The elevating cylinder 33 is connected to the HC frame 34 and the WC frame 35 by a pin 33a, and can be bent around the pin 33a.

  The HC frame 34 has a built-in (provided) holding catch (locking piece) 36 (hereinafter referred to as “HC36”) that fits (including engagement with a gap) into the tooth portion 32 of the rack 31. A holding catch drive cylinder 37 (hereinafter referred to as “HC cylinder 37”) for moving the HC 36 in the horizontal direction is provided in the anti-rack direction. The WC frame 35 has a working catch (locking piece) 38 (hereinafter referred to as “WC38”) built-in (provided), and a working catch drive cylinder 39 (hereinafter referred to as “WC”) that moves the WC 38 in the horizontal direction. Cylinder 39 ") is provided in the anti-rack direction. These HC cylinder 37 and WC cylinder 39 are alternately and independently driven and controlled as will be described later.

  As shown in FIG. 9, the lifting cylinder 33 is provided on both the left and right sides with the rack 31 interposed therebetween. In addition, a WC frame 35 provided at the upper part of the elevating cylinder 33 and an HC frame 34 provided at the lower part are also provided with the rack 31 interposed therebetween. The HC 36 and WC 38 that are advanced and retracted from the HC frame 34 and the WC frame 35 toward the rack 31 have high portions that fit into the tooth portions 32 of the rack 31, and the HC frames 34 and WC frames 35 at both ends in the width direction are high. The part which advances and retreats along is formed with the low thick board. These WC 38 and HC 36 are formed with a plate thickness that can support a load when the elevating thruster device 20 is raised and lowered and a vertical load acting on the elevating thruster device 20 during operation.

  The HC 36 and WC 38 advance and retreat along guide portions 34 a and 35 a provided on the HC frame 34 and the WC frame 35. The HC 36 is fitted into and removed from the rack 31 by the HC cylinder 37 provided on the HC frame 34, and the WC 38 is fitted by the WC cylinder 39 provided on the WC frame 35. The HC frame 34 is fixed to a load support structure 9 provided in the hoistway 2 on the hull 1 side with the rack 31 interposed therebetween. The HC frame 34 is fixed by, for example, pin coupling attachment or bolt attachment so that it can be welded or attached or detached.

  As shown in FIG. 10, the HC frame 34 provided with the rack 31 interposed therebetween is provided with a guide portion 34 a for guiding the HC 36, and the HC 36 is directed toward the rack 31 by the HC cylinder 37 provided in the opposite rack direction. Can be removed.

  Further, as shown in FIG. 11, the WC frame 35 is also provided with the rack 31 sandwiched in the same manner as the HC frame 34, but the left and right portions are integrally formed (FIG. 9). The WC frame 35 is provided with a guide groove 41 that can be moved up and down along a guide member 40 provided in the base portion 31 a of the rack 31. The guide members 40 are provided on both sides of the rack 31 so as to be continuous in the vertical direction of the canister 21. Therefore, the WC frame 35 is always moved up and down while the guide groove 41 is guided by the guide member 40 provided in the canister 21.

  In addition, since the WC frame 35 can be moved up and down along the guide members 40 provided on both sides of the rack 31 as described above, the WC frame 35 in a state where the WC 38 is detached from the tooth portion 32 of the rack 31 is also attached to the canister 21. Can be moved up and down. Therefore, the lifting device 30 does not need to increase the size of the WC frame 35 even if the cross-section of the canister 21 is increased due to the increase in the size of the swivel thruster 22. Can respond.

  Next, the raising / lowering operation of the lifting / lowering thruster apparatus 20 by the lifting / lowering apparatus 30 will be described with reference to FIGS. In this description, the engagement and disengagement of the catches 36 and 38 by the WC cylinder 39 and the HC cylinder 37 and the lifting and lowering operation of the rack 31 provided in the canister 21 of the lifting and lowering thruster device 20 by the lifting and lowering cylinder 33 will be described. Further, the figure shows the state of the limit switch for checking whether the catches 36 and 38 are fitted and removed, the change of the vertical position (changeover), the state of the valve operation of the elevating cylinder 33 for raising and lowering the catches 36 and 38, and the like. ing. Note that the catch supporting the load of the liftable thruster device 20 is hatched. Further, a horizontal line is shown in a part of the rack 31 so that the raising / lowering operation becomes clear.

  (A) to (i) shown in FIG. 12 and (a) to (i) shown in FIG. 13 are states in which the catches 36 and 38 are receiving a downward positive load from the rack 31 (“the weight of the lifting thruster” -The lift operation in the state of buoyancy acting on the lift thruster device> 0 ". (A)-(i) shown in FIG. 12 is a figure which shows 1 cycle of raising operation | movement, 1 cycle which raises the raising / lowering thruster apparatus 20 is demonstrated based on this figure.

[Climbing operation]
The state shown in FIG. 12A is a state in which the liftable thruster device 20 is supported by the HC 36 fitted to the tooth portion 32 of the rack 31 by the HC cylinder 37 of the lift device 30. It explains from.

  First, the WC 38 is slightly raised by the elevating cylinder 33, the load of the elevating thruster device 20 is supported by the WC 38, and then the HC 36 is detached from the tooth portion 32 of the rack 31 (b), (c).

  Next, the WC 38 is raised by the elevating cylinder 33 and the WC frame 35 is raised by one pitch of the rack 31 while pressing the HC 36 against the rack 31 by the HC cylinder 37. As a result, the HC 36 is fitted into the tooth portion 32 at a position one pitch below the rack 31 (d), (e).

  Next, the WC 38 is slightly lowered by the elevating cylinder 33, and the load of the elevating thruster device 20 is supported by the lower HC 36, and then the WC 38 is detached from the tooth portion 32 of the rack 31 (f), (g).

  Next, the WC 38 is lowered by the elevating cylinder 33 and the WC 38 is lowered by one pitch of the rack 31 while the WC cylinder 39 presses the WC 38 toward the rack 31. As a result, the WC 38 is fitted to the tooth portion 32 at a position 1 pitch below the rack 31 (h), (i).

  In this manner, the elevating thruster device 20 raised by one pitch of the rack 31 is raised sequentially by repeating the above operation.

[Descent action]
(A)-(i) shown in FIG. 13 is a figure which shows 1 cycle of descent | fall operation | movement. One cycle for lowering the elevating thruster device 20 will be described with reference to FIG.

  The state shown in FIG. 13A is a state in which the lifting / lowering thruster device 20 is supported by the HC 36 fitted to the tooth portion 32 of the rack 31 by the HC cylinder 37 of the lifting / lowering device 30. explain.

  First, the WC 38 is slightly raised by the elevating cylinder 33, the load of the elevating thruster device 20 is supported by the WC 38, and then the HC 36 is detached from the tooth portion 32 of the rack 31 (b), (c).

  Next, the WC 38 is lowered by the lifting cylinder 33 and the WC frame 35 is lowered by one pitch of the rack 31 while pressing the HC 36 against the rack 31 by the HC cylinder 37. As a result, the HC 36 is fitted into the tooth portion 32 at a position one pitch above the rack 31 (d), (e).

  Subsequently, after the lifting cylinder 33 is slightly lowered and the load of the lifting thruster device 20 is supported by the HC 36, the WC 38 is detached from the tooth portion 32 of the rack 31 (f), (g).

  Next, the WC 38 is raised by the elevating cylinder 33 and the WC frame 35 is raised by one pitch of the rack 31 while pressing the WC 38 toward the rack 31 by the WC cylinder 39. As a result, the WC 38 is fitted to the tooth portion 32 at a position one pitch above the rack 31 (h), (i).

  In this way, the elevating thruster device 20 lowered by one pitch of the rack 31 is sequentially lowered by repeating the above operation.

  (A) to (i) shown in FIG. 14 and (a) to (i) shown in FIG. 15 are states in which the catches 36 and 38 receive an upward load weight from the rack 31 ("the own weight of the lifting thruster device" -The lifting operation in the state of buoyancy <0 "acting on the lifting thruster device. (A)-(i) shown in FIG. 14 is a figure which shows 1 cycle of raising operation | movement, 1 cycle which raises the raising / lowering thruster apparatus 20 is demonstrated based on this figure.

[Climbing operation]
The state shown in FIG. 14 (a) is a state in which the lifting / lowering thruster device 20 is supported by the HC 36 fitted to the tooth portion 32 of the rack 31 by the HC cylinder 37 of the lifting / lowering device 30. explain.

  First, the WC 38 is slightly lowered by the elevating cylinder 33, and the load of the elevating thruster device 20 is supported by the WC 38, and then the HC 36 is detached from the tooth portion 32 of the rack 31 (b), (c).

  Next, the WC 38 is raised by the elevating cylinder 33 and the WC frame 35 is raised by one pitch of the rack 31 while pressing the HC 36 against the rack 31 by the HC cylinder 37. As a result, the HC 36 is fitted into the tooth portion 32 at a position one pitch below the rack 31 (d), (e).

  Next, the WC 38 is slightly raised by the lifting cylinder 33 and the load of the lifting thruster device 20 is supported by the HC 36, and then the WC 38 is detached from the tooth portion 32 of the rack 31 (f), (g).

  Next, the WC 38 is lowered by the elevating cylinder 33 and the WC 38 is lowered by one pitch of the rack 31 while the WC cylinder 39 presses the WC 38 toward the rack 31. As a result, the WC 38 is fitted to the tooth portion 32 at a position 1 pitch below the rack 31 (h), (i).

  In this manner, the elevating thruster device 20 raised by one pitch of the rack 31 is raised sequentially by repeating the above operation.

[Descent action]
FIGS. 15A to 15I are diagrams showing one cycle of the lowering operation. One cycle for lowering the elevating thruster device 20 will be described with reference to FIG.

  The state shown in FIG. 15 (a) is a state in which the lifting / lowering thruster device 20 is supported by the HC 36 fitted to the tooth portion 32 of the rack 31 by the HC cylinder 37 of the lifting / lowering device 30. explain.

  First, the WC 38 is slightly lowered by the elevating cylinder 33, and the load of the elevating thruster device 20 is supported by the WC 38, and then the HC 36 is detached from the tooth portion 32 of the rack 31 (b), (c).

  Subsequently, the WC 38 is lowered by the elevating cylinder 33 and the WC frame 35 is lowered by one pitch of the rack 31 while pressing the HC 36 against the rack 31 by the HC cylinder 37. As a result, the HC 36 is fitted into the tooth portion 32 at a position one pitch above the rack 31 (d), (e).

  Next, the WC 38 is slightly raised by the lifting cylinder 33 and the load of the lifting thruster device 20 is supported by the HC 36, and then the WC 38 is detached from the tooth portion 32 of the rack 31 (f), (g).

  Subsequently, the WC 38 is raised by the elevating cylinder 33 and the WC frame 35 is raised by one pitch of the rack 31 while pressing the WC 38 toward the rack 31 by the WC cylinder 39. As a result, the WC 38 is fitted to the tooth portion 32 at a position one pitch above the rack 31 (h), (i).

  In this way, the elevating thruster device 20 lowered by one pitch of the rack 31 is sequentially lowered by repeating the above operation.

  As mentioned above, the raising / lowering operation of the raising / lowering thruster apparatus 20 by the said raising / lowering apparatus 30 is performed by the raising / lowering system by what is called a short pitched insect picking movement.

  Next, based on FIGS. 16 (a), (b) to FIGS. 21 (a), (b), the operation of the elevating type thruster apparatus which is moved up and down by the elevating apparatus will be described. FIGS. 16A, 16B to 17A, 17B show the operation of the elevating thruster apparatus 20 according to the first embodiment shown in FIGS. FIGS. 18A, 18B to 21A, 21B show the operation of the liftable thruster apparatus 50 according to the second embodiment. The operation of these two embodiments will be described below.

[Operation of First Embodiment]
The lifting thruster device 20 of the first embodiment shown in FIG. 16A is an example in which a rack 31 provided on the side of the canister 21 protrudes upward from the upper end of the canister 21. In the case of the first embodiment, the lifting device 30 is fixed at a fixed position on the hoistway 2. The position where the lifting device 30 is provided is set to a position where the canister 21 can be raised to a position where the thruster 22 can be removed above the draft surface W, as will be described later.

  In the case of the first embodiment, as shown in FIG. 16 (a), a thruster 22 (having a height L in the drawing) at a position (operating position) protruding from the ship bottom 10 is shown in the above figure by the lifting device 30. As shown in FIGS. 12 (a) to (i) or FIGS. 14 (a) to (i), the WC 38 and the HC 36 are alternately engaged / disengaged so as to be raised. The state shown in FIG. 16 (b) shows the position of the state in which the thruster 22 is stored from the ship bottom 10 (the position at the time of navigation).

  Thereafter, by repeating the operations shown in FIGS. 12 (a) to (i) or FIGS. 14 (a) to (i), the thruster 22 is moved to the draft surface W of the hoistway 2 as shown in FIG. 17 (a). It is raised to the position (maintenance inspection position) of the maintenance inspection floor 11 provided at a predetermined position above. Then, as shown in FIG. 17 (b), an operator or the like removes the thruster 22 from the canister 21 on the maintenance / inspection floor 11 and moves it toward the maintenance / inspection floor 11. In this example, as shown in FIG. 17A, the maintenance inspection floor 11 is provided at a position of height B from the draft surface W with respect to the height A from the ship bottom 10 to the draft surface W. The height space of the maintenance inspection floor 11 is set to a height obtained by adding the working height C to the height L of the thruster 22. Therefore, the rising amount of the canister 21 is the height H.

  Thus, since the structure which raises the thruster 22 from the draft surface W can be performed by the compact raising / lowering device 30, even if the thruster 22 fails in the offshore operation point, it is inspected and repaired at the operation point. The elevating thruster device 20 capable of performing the above can be provided.

[Operation of Second Embodiment]
Next, a second embodiment will be described based on FIGS. 18 (a) and (b) to FIGS. 21 (a) and (b). The same components as those in the first embodiment will be described with the same reference numerals. In the second embodiment, the left and right portions are integrally formed in the same way as the WC frame 35 so that the HC frame 34 of the lifting device 33 can also be lifted and lowered along the guide member 40 of the canister 21. Provided (see FIG. 11). Further, the height of the rack 31 provided in the canister 21 is a position where the thruster 22 is stored in the hoistway 2 (the position at the time of navigation), and the rack 31 is above the upper deck position (the position of the hull 1 shown in the figure). So that it does not protrude. Therefore, according to the second embodiment, it can be used when it is not allowed to have a configuration that protrudes upward during voyage or the like. Moreover, this 2nd Embodiment can be utilized also when the upper deck position becomes low and the raising / lowering apparatus 30 cannot be equipped in a predetermined height position like 1st Embodiment.

  In the lifting type thruster apparatus 50 according to the second embodiment shown in FIG. 18A, the rack 31 provided on the side of the canister 21 is provided up to the upper end position of the canister 21. In the case of the second embodiment, the lifting device 30 is fixed at a predetermined position of the hoistway 2, but the position where the lifting device 30 is provided can be changed as will be described later.

  Also in the case of the second embodiment, as shown in FIG. 18 (a), the thruster 22 protruding from the ship bottom 10 is moved by the lifting / lowering device 30 to the above-described FIG. 12 (a) to (i) or FIG. 14 (a). As shown in (i), the WC 38 and the HC 36 are raised by performing an operation of engaging / disengaging alternately. The state shown in FIG. 18B shows a state in which the thruster 22 is stored from the ship bottom 10. In the elevating thruster device 50 of the second embodiment, there is nothing that protrudes upward from the upper deck of the hull 1 in this state.

  Thereafter, by repeating the operations shown in FIGS. 12 (a) to (i) or FIGS. 14 (a) to (i), the thruster 22 is raised to the vicinity of the draft surface W as shown in FIG. 19 (a). Let In this state, the load holding device 12 provided in the hoistway 2 (the device that supports the load by fitting the same configuration as the catch 36 to the tooth portion 32 of the rack 31 at the position indicated by the two-dot chain line) The load of the liftable thruster device 50 is temporarily held.

  Then, the structure which has fixed the HC frame 34 of the raising / lowering apparatus 30 to the hull 1 is removed, and the raising / lowering apparatus 30 is made a free state. Then, by repeating the operations shown in FIGS. 15 (a) to 15 (i), the lifting device 30 is raised along the rack 31 to a predetermined upper position as shown in FIG. 19 (b). As will be described later, the predetermined upper position is set to a position where the thruster 22 of the liftable thruster apparatus 50 can be raised to the position of the maintenance inspection floor 11 provided above the draft surface W.

  Next, as shown in FIG. 20A, the load support structure 13 is provided below the lifting device 30 in the hoistway 2. Then, as shown in FIG. 20 (b), the lifting device 30 is lowered by a predetermined amount to fix the HC frame 34 to the load support structure 13. As a result, the load of the elevating thruster device 50 is supported by the load support structure 13 via the elevating device 30. Thereafter, the load holding device 12 that temporarily holds the load of the elevating thruster device 50 is removed.

  Thereafter, by repeating the operations shown in FIGS. 12 (a) to (i) or FIGS. 14 (a) to (i), the thruster 22 is moved to a predetermined position in the hoistway 2 as shown in FIG. 21 (a). Raise to the position of the maintenance inspection floor 11 provided. Then, as shown in FIG. 21 (b), an operator or the like removes the thruster 22 from the canister 21 on the maintenance / inspection floor 11 and moves it toward the maintenance / inspection floor 11.

  Thus, since the structure which raises the thruster 22 from the draft surface W can be performed by the compact raising / lowering device 30, even if the thruster 22 fails in the offshore operation point, it is inspected and repaired at the operation point. It is possible to provide the liftable thruster apparatus 50 capable of performing the above. Moreover, according to the elevating thruster device 50 of the second embodiment, it is possible to eliminate the configuration that protrudes greatly upward.

  As described above, according to the elevating thruster devices 20 and 50, the canister 21 is provided with the pair of racks 31 having a required length in the vertical direction, and the pair of elevating devices 30 are disposed at the required height position of the hoistway 2. By doing so, it is possible to stably raise and lower the thrusters 22 of the liftable thruster apparatuses 20 and 50 between the operating position and the maintenance inspection position.

  In addition, the lifting / lowering system of the lifting / lowering thruster devices 20 and 50 by the lifting / lowering device 30 is made to be a method of repeating the so-called worming movement by the lifting / lowering cylinder 33 with a short stroke, thereby making the lifting / lowering device 30 compact and inexpensive. it can. Further, since the lifting cylinder 33 of the lifting device 30 may have a short stroke, it is easy to provide sufficient buckling strength when lifting the lifting thruster devices 20 and 50 that are heavy objects.

  In addition, since the lower side of the elevating cylinder 33 (the direction of the cylinder does not matter) is fixed to the hoistway 2, the weights of the elevating thruster devices 20 and 50 are supported on the bore side having a larger area. As a result, the optimum design of the elevating cylinder 33 becomes possible.

  Accordingly, it is possible to provide the lifting and lowering thruster apparatuses 20 and 50 including the compact lifting and lowering apparatus 30 that can be applied at a reduced cost even in an excavation ship having a plurality of thrusters 22 in one ship.

  By the way, the elevating-type thruster devices 20 and 50 are provided with predetermined intervals S1 and S2 between the hoistway 2 and the hoistway 2 of the hull 1 in order to move up and down. Therefore, in the sea area away from the land, the draft surface W greatly fluctuates due to the influence of waves and the like. In such a case, as described above, normal operation may be hindered by fluctuations in the draft surface W when the elevating thruster devices 20 and 50 are raised and lowered.

  Therefore, as shown in FIGS. 1, 2 and 7, the lifting thruster 20 (50) has the entire circumference of the canister 21 as described above at the position level of the lateral load support guides 3 and 4 in the operating position. The surrounding plate 7 is provided with a space S3 between the entire circumference of the hoistway 2 and a small gap S3 so as to exert a throttling effect (FIG. 7). As described above, the surrounding plate 7 is provided on the lowermost support guide 3 and the lower one support / lift guide 4, and the water surface between the hoistway 2 and the canister 21 is greatly increased by waves or the like. Suppresses vertical fluctuations. In this embodiment, it is preferable that the surrounding plate 7 is provided at the position level of the lowermost part of the canister 21 and the support / elevating guide 4 located at the upper part of the canister 21 in the operating position, so that the movement of water can be reliably suppressed.

  Further, as shown in FIGS. 22 and 23, in consideration of the above-described waves and the like, when the liftable thrusters 20 and 50 are in operation, the load is set in the relationship between the rack 31 and the catches 36 and 38 as follows. You may hold it. The direction of the static vertical load acting on the lifting / lowering thruster device 20 depends on the relationship between the weight of the lifting / lowering thruster device 20 and the size of the buoyancy acting on it in the state where the dynamic load due to the waves is not acting. Determined.

  FIG. 22 shows a static state in which a downward positive load is applied to the lifting / lowering thruster device 20, that is, "the weight of the lifting / lowering thruster device-buoyancy acting on the lifting / lowering thruster device> 0". The load holding state is shown.

  The relationship between the rack and the catch shown in FIG. 22 is that the WC 38 built in the WC frame 35 is pulled by pulling the WC 38 built in the WC frame 35 in the direction of the HC frame 34 with the lifting cylinder 33. The racks 31 are pressed against each other. Thereby, the vertical movement of the canister 21 due to waves during operation is suppressed.

  Further, FIG. 23 shows a static state in a state where an upward load weight is applied to the lifting / lowering thruster device, that is, “the weight of the lifting / lowering thruster device−the buoyancy acting on the lifting / lowering thruster device <0”. The load holding state is shown.

  The relationship between the rack and the catch shown in FIG. 23 is that the WC 38 built in the WC 38 and the HC frame 34 is pushed by pushing the WC 38 built in the WC frame 35 in the direction opposite to the HC frame 34 by the lifting cylinder 33. And pull the rack 31 to each other. Thereby, the vertical movement of the canister 21 due to waves during operation is suppressed.

  In these hydraulic circuits shown in FIGS. 22 and 23, an accumulator 45, a low pressure relief valve 46a, a high pressure relief valve 46b, and the like for maintaining the state in which the rack 31 is pushed and pulled up and down by the elevating cylinder 33 with the HC 36 and the WC 38, Only the check valve 47 and the tank 48 are shown, and illustration of a pump, a direction switching valve, etc. is omitted. The pressure of the accumulator 45 and the low pressure relief valve 46a is set to a pressure slightly higher than the pressure at which the elevating cylinder 33 can elevate and lower the empty WC frame 35.

  In this manner, the vertical static load acting on the canister 21 is held by the HC 36 built in the HC frame 34 fixedly attached to the hoistway 2. In this holding, both catches 36 and 38 are held in a push-pull state so as to hold a dynamic load acting in the opposite direction to the static load due to the waves with the HC 36 and WC 38 provided at the vertical position of the lifting device 30. . Thereby, the vertical motion of the canister 21 by the wave at the time of operation | movement can be suppressed.

  In the above-described embodiment, a pair of opposing racks 31 extending in the vertical direction (vertical direction) are provided on the outer surface in the widthwise central portion of the two opposing surfaces of the canister 21. As long as it passes through the center point of the horizontal cross section, it may be on a diagonal line, or may be two pairs instead of a pair, and is not limited to the above embodiment.

  The rack 31 has a substantially rectangular shape of the tooth portion 32. However, the rack 31 is formed in a concavo-convex shape with a fixed pitch and can support the liftable thruster devices 20 and 50 by fitting the catches 36 and 38. What is necessary is just to be a fitting hole shape of a fixed pitch, for example, and it is not limited to the said embodiment.

  Furthermore, the above-described embodiment shows an example, and various modifications can be made without departing from the gist of the present invention, and the present invention is not limited to the above-described embodiment.

  The elevating thruster apparatus according to the present invention can be used for an excavation ship or the like that wants to perform inspection and maintenance by raising the thruster to a position above the draft surface in the event of a failure or the like.

1 hull
2 hoistway
3 Support guide
4 Support / Elevation Guide 4a Support Guide 4b Elevation Guide
5 Lifting guide
6 Pad
7 Enclosure
8 Jack
9 Load support structure (fixed part)
10 Ship bottom 11 Maintenance inspection floor 12 Load holding device 13 Load support structure (fixed part)
20 Lifting Thruster Device 21 Canister 22 Thruster 30 Lifting Device 31 Rack 31a Base Part 32 Tooth Part 33 Lifting Cylinder 33a Pin 34 Holding Catch Frame (HC Frame)
34a Guide 35 Working catch frame (WC frame)
35a Guide 36 Holding catch (HC)
37 Holding Catch Drive Cylinder (HC Cylinder)
38 Working catch (WC)
39 Working catch drive cylinder (WC cylinder)
40 Guide member 41 Guide groove 50 Lifting thruster S1 and S2 interval
T gap
W draft surface

Claims (8)

A lifting thruster device comprising: a thruster provided so as to protrude downward from the bottom; and a canister for moving up and down in a hoistway provided in a hull incorporating a driving device for driving the thruster,
At least a pair of racks of a required length provided in the vertical direction on the outer surface of the canister, the teeth having a constant pitch in the vertical direction;
A guide member provided in the vertical direction along each rack;
A pair of elevating devices that elevate and lower the canister along the pair of racks between the operating position of the thruster and a position above the draft surface within the hoistway;
The pair of lifting devices includes a pair of upper and lower catches that are independently fitted to and disengaged from the top and bottom tooth portions of the rack, a pair of upper and lower frames provided with the catches, and a pair of upper and lower frames. An elevating cylinder provided between,
The lifting and lowering thruster device, wherein the lifting cylinder is configured to move up and down one frame fixed to the hoistway side with the other frame as a guide.   The elevating thruster device according to claim 1, wherein the pair of upper and lower frames are attached so as to fix a frame positioned below to the hoistway. The hoistway includes a maintenance inspection floor at a position above the draft surface,
The canister includes a rack having a required length for raising the thruster to the maintenance inspection floor position,
The elevating-type thruster apparatus according to claim 1 or 2, wherein the elevating apparatus is disposed at a required height position of the hoistway so that the thruster can be raised and lowered from an operating position to a maintenance inspection floor position.   The pair of upper and lower frames includes a drive cylinder that allows the catches to be fitted and detached independently from each other in the upper and lower positions, and a guide portion that fits or removes the catches from the teeth of the rack by the expansion and contraction of the drive cylinders. The raising / lowering thruster apparatus of any one of Claims 1-3 which have.   When the thruster is in operation, the elevating cylinder engages the pair of upper and lower catches with the teeth of the rack, and applies a force in the reverse direction to the catch to hold the vertical load acting on the canister. The raising / lowering thruster apparatus of any one of Claims 1-4 comprised by these. The hoistway includes a fixed portion of the elevating device provided at a plurality of locations separated in the vertical direction,
A load holding device that temporarily holds the load of the elevating thruster device when changing the fixing portion;
The said raising / lowering apparatus is a raising / lowering thruster apparatus of any one of Claims 1-5 which has a fixing means which can be attached or detached to the fixing | fixed part of the said hoistway.   The hoistway includes a support guide that supports a horizontal force acting on the canister, and a surrounding plate that reduces the distance between the canister and the hoistway in the entire circumference at the position of the support guide. The raising / lowering thruster apparatus of any one of Claims 1-6.   The elevating-type thruster apparatus according to claim 7, further comprising a jack that horizontally supports the canister between the support guide and the canister.

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