JP4668162B2 - Retractable thrusters and ships with thrusters - Google Patents

Description

  The present invention relates to a ship with a thruster provided with a side thruster that enables lateral movement or turning of the ship, and a retractable thruster thereof.

  FIG. 5 is a front view of the ship 1. As shown in FIG. 5, in addition to the propulsion propeller 2 and the steering plate 3 that are provided at the stern, the ship 1 has a function for moving the ship in the lateral direction at the time of connection / disconnection to the quay of the ship. Thrusters 4, 5, 6, and 7 are provided. The bow thruster 4 is provided at the bow, and the stearn rasters 5, 6, and 7 are provided at the stern, one or both of which are equipped.

  FIG. 6A is a front view of the ship 1, and FIG. 6B is a plan view of the ship 1. As shown in FIG. 6, the thrusters 4 and 5 are provided with a thruster tunnel 10 penetrating in the hull width direction in the hull, and the propeller is arranged in the tunnel 10 with the rotation axis perpendicular to the hull traveling direction. It is attached to.

  The thruster 6 provided at the stern is fixed to the hull with the propeller rotation axis perpendicular to the hull traveling direction, and when the water surface is in the state (a) as shown in the front view of FIG. Although it functions as a thruster, when the water surface is in the state (b), it cannot function as a thruster. When the hull is made of light alloy or FRP (fiber reinforced plastic), the water surface is normally in the state of (b). Therefore, there is a thruster 7 that is movable in the vertical direction. The thruster 7 is driven in the vertical direction by a driving device 8 such as an air cylinder. When the water surface is low as shown in (b), the thruster 7 is lowered by the driving device 8 so that the thruster 7 is positioned below the water surface. That is, as shown in FIG. 8, when the flooding is deep, the driving device 8 positions the thruster 7 in the raised position, and as shown in FIG. 9, when the flooding is shallow, the driving device 8 causes the thruster 7 to move. In either case, the drive device 8 adjusts so that the thruster 7 is positioned below the water surface. FIG. 9 is a plan view of the hull showing the thruster 7 and the driving device 8.

  Patent Documents 1 to 4 disclose such ships with side thrusters.

JP-A-9-295571 JP-A-10-278871 Japanese Patent Laid-Open No. 10-138898 JP 2000-85690 A

  However, the above-described conventional apparatus has the following problems. First, as shown in FIG. 6, in the case of thrusters 4 and 5, there is a water resistance due to the thruster tunnel 10 and turbulence is generated during running. Further, cavitation (cavity) is generated in the thruster tunnel 10, and this is caught in the propeller to generate vibration. For this reason, the hull side wall 11 in front of the thruster tunnel 10 is expanded in the hull width direction, or the hull side wall 12 in the rear of the thruster tunnel 10 is dented to reduce the inflow of cavitation into the tunnel 10. The shape is designed to alleviate the problem even a little.

  In particular, since the thruster 5 is provided at a position very close to the propeller 2 for propulsion, the above-described problems are more greatly affected and are attached only to a low-speed ship.

  In the case of a fixed type like the thruster 6, unless the thruster 6 is always located below the surface of the water, thrust in the transverse direction of the hull can not be obtained by the thruster, and light weight made of light alloy or FRP, etc. Cannot be used with a hull

  In addition, the thruster 7 that can be moved in the vertical direction by the driving device 8 requires a modification permission in accordance with the change in the volume and length of the ship, and cannot be mounted on a ship that has a limit of tonnage. Further, in the case of the thruster 7, an installation space is required by the length of the air cylinder in the vertical direction for the installation, and a ship having a low stern height cannot be attached.

  Further, if the thruster 7 protrudes as shown in FIG. 9 and the ship normally travels, the mounting portion of the thruster 7 cannot withstand the resistance to water transportation, and the cylinder of the driving device 8 The piston is bent, and the thruster 7 cannot be retracted upward. Further, when the rope and the suspended matter are easily caught on the thruster 7 and the ship is working near the net, the thruster 7 is disabled. Therefore, even if the thruster 7 is installed on the hull, its use range is limited.

  The present invention has been made in view of such a problem, and even in a shallow water vessel, the thruster is surely below the surface of the water, so that it is possible to prevent the generation of the transport resistance and turbulence and cavitation caused by the thruster tunnel. It is an object of the present invention to provide a ship with a thruster and a retractable thruster in which vibration and speed reduction caused by the above are prevented.

The retractable thruster according to the present invention includes a case that is supported by the hull so as to be rotatable between a state in which it is stored in the hull and a state in which it protrudes downward from the bottom of the hull. A propeller installed perpendicular to the vehicle, a drive device for rotating the case between a retracted position in the hull and a use position protruding downward from the bottom of the ship, and a sensor for detecting the pressure acting on the case And a control unit that stores the case in a ship body by the driving device when a detected pressure of the sensor exceeds a predetermined value .

  The case includes a support shaft that supports a direction orthogonal to the longitudinal direction of the hull as a rotation axis, a pair of side plates that are fixed to the support shaft and have a certain opening angle, and the other side portion of the side plate. It is preferable that a curved plate is interposed between the pair of side plates and the curved plate to form a fan-shaped frame.

  Further, in this case, the case includes a support portion that is provided so that water can pass through one end portion of the side plate and the curved plate in the longitudinal direction of the support shaft, and a rotation of the propeller supported by the support portion. A drive unit, and the propeller is preferably attached to the rotation drive unit.

  A ship with a thruster according to the present invention includes the above-described retractable thruster.

  In the present invention, when the ship is transported, the case is stored in the hull, so there is no protrusion from the hull. In the present invention, there is no thruster tunnel. Thus, in the present invention, since there is no projection and there is no thruster tunnel, there is no transmission resistance caused by the thruster tunnel and projections, turbulence does not occur, and cavitation (cavity phenomenon) ) And therefore no vibrations due to these occur.

  According to the invention of claim 2 of the present application, since the case is formed of a pair of side plates and a curved plate and has a fan-shaped frame, the ship advances or retreats while the thruster protrudes downward from the hull. However, since the water flow is restricted by these side plates and the curved plate, the resistance is small. In addition, since the prop is located in the case and does not directly receive the water flow, an overload is not applied to the propeller itself and the propeller is not damaged. In addition, since the case is rotatably supported by a support shaft installed on the hull, even if a resistance force due to water flow acts on the case, it does not directly act on the piston of the air cylinder of the drive device, for example. Therefore, breakage of these pistons and the like is prevented.

  According to a fourth aspect of the present invention, the pressure acting on the case is detected by a sensor, and when the detected pressure exceeds a predetermined value, the control unit drives the driving device to store the case in the hull. With this configuration, it is possible to prevent the case from being damaged by applying an excessive force to the case.

  Hereinafter, embodiments of the present invention will be specifically described with reference to the accompanying drawings. 1 to 4 are views showing an embodiment of the present invention. FIG. 1 is a plan view of the stern, FIGS. 2 and 3 are front views of the stern, and FIG. 4 is a front view of the stern showing the operation. However, FIG. 1 is a plan view of the state of FIG.

  In the present embodiment, a retractable thruster 20 is installed in the vicinity of the stern propulsion propeller 2 and the steering plate 3 of the ship 1. In the retractable thruster 20, a case 31 is rotatably supported by a support shaft 32 having a rotation axis in a direction perpendicular to the longitudinal direction of the hull. The case 31 has a shape in which a pair of side plates 21 and 22 and a curved plate 23 are assembled in a sectoral cross section, and the side portion of the side plates 21 and 22 is constant in the central part of the sector shape. The other side portions of the side plates 21 and 22 are fixed to both end edges of the curved plate 23. The fan-shaped central portion is fixed to the support shaft 32, whereby the case 31 rotates about the support shaft 32 as a rotation center. The support shaft 32 is provided on the ship bottom or in the vicinity of the ship bottom. Therefore, as shown in FIG. 2, the case 31 can take a state of being housed in the hull and a state of protruding downward from the hull. And can be rotated between these two states. The tip of the piston of the air cylinder 25 is rotatably connected to the side plate 22 with respect to the side plate 22, and the case 31 can rotate using the air cylinder 25 as a rotation drive device. A hydraulic cylinder may be used instead of the air cylinder.

  Support portions 29 and 30 are fixed to both ends of the side plates 21 and 22 of the case 31 and the curved plate 23 in the hull width direction. The support portions 29 and 30 are, for example, rod-shaped so as not to disturb the flow of water. A propeller rotation drive unit 27 is fixed to one support unit 29 with its rotation axis perpendicular to the longitudinal direction of the hull, and a propeller 28 is attached to the rotation shaft of the rotation drive unit 27.

  A sensor (not shown) detects pressure acting on the case 31. As shown in FIG. 4, a load due to a water flow is applied to the case 31 when the ship 1 moves forward despite the case 31 protruding downward from the bottom of the ship. This pressure acts to push the case 31 back into the hull. For example, a pressure sensor is provided between the side plate 22 and the hull, and the pressure exerted on the hull from the side plate 22 is detected. Thus, the pressure acting on the case 31 can be detected. When the detected pressure exceeds a predetermined value, the control unit (not shown) retracts the piston of the air cylinder 25 and stores the case 31 in the hull as shown in FIG. It has become.

  Further, as shown in FIG. 4, the case 31 is provided with a stopper 40, and the side plate 22 of the case 31 is moved downward from the bottom of the ship by the stopper 40 being locked to the locking portion on the hull side. It will not drop. That is, the case 31 forms a stopper 40 with the side plate 22 extending slightly outward. Since the stopper 40 of the side plate 22 is locked to the locking portion provided on the ship bottom, the case 31 is prevented from further rotating downward, and the air cylinder 25 connected to the case 31 is excessively large. A load is not applied.

  Next, the operation of the retractable thruster configured as described above will be described. As shown in FIG. 2, the case 31 is housed in the ship body when the ship 1 is normally transported (the piston of the air cylinder 25 is retracted). During this cruising (retracted state), there is no protrusion outside the bottom of the ship, and the bottom of the ship is flat even at the installation position. Therefore, the speed due to the transmission resistance, turbulence and cavitation inherent to the fixed thruster. And no vibrations occur.

  And when the ship 1 touches the quay or leaves the quay, as shown in FIG. 3, the piston of the air cylinder 25 is advanced and the case 31 is rotated downward (left rotation in the figure), The stopper 40 is brought into contact with the locking portion of the ship bottom. Then, the case 31 protrudes downward from the hull, and accordingly, the propeller 28 in the case 31 protrudes downward from the ship bottom. For this reason, even when the flooding is shallow, the propeller 28 is surely located below the water surface.

  Therefore, when the rotary drive unit 27 drives the propeller 28 to rotate, a lateral force acts on the hull, and the hull can be moved or turned in the horizontal direction, making contact with the quay easy. It can be carried out. Even in a shallow watercraft, the propeller 28 is surely below the surface of the water as described above, so that air bubbles do not occur and air does not flow in, and the performance according to the specifications can be exhibited. .

  After the contact / separation work is completed, the propeller 28 is stopped, the piston of the air cylinder 25 is retracted, the case 31 is stored in the hull, the propeller 2 is rotated, and the ship is moved forward or backward.

  However, at this time, if the ship 1 forgets to store the case 31 and enters the normal shipping, as shown in FIG. 4, when moving forward, a load directed toward the stern is applied to the side plate 21 due to the water flow, and the vehicle moves backward. Sometimes, a load toward the bow is applied to the curved plate 23 by a water flow. However, in the present embodiment, during advance, the side plate 21 of the case 31 receives this water flow, so that an excessive load from the water flow is not applied to the propeller 28. In addition, since the sensor detects the load acting on the case 31, when the detected pressure exceeds a predetermined value, the control unit drives the air cylinder 25 to retract the case 31 into the hull. The case 31 is reliably prevented from being damaged by the resistance from the water flow.

  On the other hand, when the ship 1 moves backward, the water flow acts on the curved plate 23 and a load in the bow direction is applied to the curved plate 23, but this water flow flows along the curved surface of the curved plate 23. A large resistance force does not act on the curved plate 23. Further, since the case 31 is locked by the stopper 40, the load acting on the case 31 is supported by the stopper 40 even if a water flow load is applied to the case 31. Furthermore, at the time of reverse drive, the speed of the ship is 3 to 5t at most, and a load that damages the case 31, the stopper 40, and further the air cylinder 25 is not applied.

  In addition, since the case 31 is assembled by the side plates 21 and 22 and the curved plate 23, ropes or floating objects in the sea are entangled in the case 31 and are also prevented from being caught, and the case 31 protrudes downward from the ship bottom. Smooth navigation.

It is a top view of the stern which shows embodiment of this invention. It is a front view of the stern which shows the embodiment of the present invention similarly. It is a front view of the stern which similarly shows operation | movement of the embodiment. It is a front view which shows the operation | movement at the time of navigation. It is a front view of a ship. It is a front view which shows the bow thruster 4 of a bow. It is a figure which shows Stern's thrusters 6 and 7 of a stern. It is a figure which shows the storing state of the stern thruster. It is a figure which shows the storage state of the thruster 7 of a stern similarly. It is a top view of the thruster 7 of a stern similarly.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Ship 2 Propeller 3 Steering plate 4 Bow thruster 5, 6, 7 Stern thruster 8 Cylinder 10 Thruster tunnel 11, 12 Side wall 20 Thruster 21, 22 Side plate 23 Curved plate 25 Air cylinder 27 Drive part 28 Propeller 29, 30 Support part 31 Case 32 Support shaft 40 Stopper

Claims (4)

A case that is supported by the hull so that it can rotate between a state in which it is stored in the hull and a state in which it protrudes downward from the bottom of the hull, and a propeller installed in this case with the rotation axis orthogonal to the longitudinal direction of the hull A drive device for rotating the case between a retracted position in the hull and a use position protruding downward from the bottom of the ship, a sensor for detecting the pressure acting on the case, and the detected pressure of the sensor being a predetermined value A retractable thruster comprising: a control unit configured to store the case in a ship body by the driving device when exceeding the limit .   The case includes a support shaft provided on the hull so as to be rotatable about a direction orthogonal to the longitudinal direction of the hull, a pair of side plates having one side fixed to the support shaft and forming a fixed opening angle, 2. The storage according to claim 1, further comprising: a curved plate spanned between the other side portions of the side plate, wherein the pair of side plates and the curved plate forms a sectional fan-shaped frame. Type thruster.   The case includes a support portion that is provided so that water can pass through one end of the support shaft in the longitudinal direction of the side plate and the curved plate, and a rotation driving portion of a propeller supported by the support portion. The retractable thruster according to claim 2, wherein the propeller is attached to the rotation drive unit. A ship with a thruster comprising the retractable thruster according to any one of claims 1 to 3 .

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