JPH02155898A - Speed reduction steering device for ship - Google Patents

Abstract

PURPOSE:To improve further the stopping performance and turning performance of a ship by installing speed reduction plates which can be taken in and out by a hydraulic device in a direction perpendicular sideways to the direction of the ship on the ship side of both gunwales in a ship having a rudder arranged at the rear side of a propeller. CONSTITUTION:Speed reduction plates 1 are arranged on both gunwales of a ship S so as to be taken in and out from a qunwale side in a direction perpendicular side ways to the direction of the ship. The speed reduction plates 1 can be taken in and out from grooves arranged in a direction perpendicular to a gunwale side. A hull resistance in increased rapidly and the stopping distance of the ship can be shortened extremely by projecting the speed reduction plates on both gunwales sideways. In the case of making a turning performance better, the hull resistance can be increased rapidly and the turning performance can be improved by projecting the speed reduction plates 1 outside the ship. Thus, the stopping performance of the ship can be improved and the turning performance can be improved furthermore.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a deceleration steering device for a ship.

(Conventional technology) Ships are required to have good maneuverability in port areas.

It is also necessary to have good deceleration and stopping performance to avoid collisions. To decelerate to a stop, the propulsion device is stopped or reversed, but the ship does not stop immediately and stops after traveling about 5 to 10 times the length of the ship. In addition, in such sea areas, maneuverability deteriorates as the water depth becomes shallower. That is, as shown in FIG. 7, when the water depth becomes shallow, the turning performance deteriorates as shown by the dotted line.

The following types of deceleration assist devices for ships are known.

1) A tanker with parachutes ha attached to both sides (Figure 8 (a)).

2) A tanker with a brake flap b installed at the stern (Fig. 8(b)).

3) A tanker with a water absorption duct LC installed in the bow (Fig. 8(C)).

However, there has not yet been an example in which a deceleration assist device has been used for the purpose of improving maneuverability during forward movement, especially turning performance.

(Problem to be solved by the invention) =2 In view of the conventional technology, while aiming to improve the stopping performance of ships,
It is an object of the present invention to provide a device that can also improve turning performance when moving forward.

(Means for Solving the Problems by the Invention) In a type of ship in which the rudder is placed behind the propulsion machine, deceleration plates that can be moved in and out vertically and laterally by a hydraulic device are provided on both sides of the ship.

In addition, in a type of ship in which the rudder is placed behind the propulsion unit, a notch with a fan-shaped planar shape is provided in the vertical direction on the side of the ship, a reduction plate is hinged to the corner of the notch, and the reduction plate is vertically stretched. It is possible to rotate between the protruding position and the position covering the fan-shaped notch.

(First Embodiment) In FIG. 1, reference numeral 1 denotes a speed reduction plate provided on both sides of a ship S, which can be entered and exited vertically from the side.

The deceleration plate 1 can move in and out of a groove 2 provided vertically on the gunwale, but at this time, rollers 3 and 3 provided on both sides of the groove 2 and the bottom
...allows for smooth entry and exit. Reference numeral 4 denotes a hydraulic piston provided deep in the groove 2, and the deceleration plate 1 moves in and out as the piston expands and contracts.

Note that it is of course possible to provide a plurality of pairs of deceleration plates 1 on the left and right sides of the ship.

(Function) 1) When stopping or decelerating, reduce or stop the rotation of the propulsion device, switch to astern if necessary, and operate the hydraulic pistons 4 to move the deceleration plates 1 on both sides in the direction of the arrow in Figure 1. overhang. Then, the hull resistance increases rapidly due to this plate 1, the deceleration of the ship becomes stronger, and the stopping distance of the ship can be significantly shortened in an emergency stop.

2) Improving turning performance In this case, by extending the speed reduction plate 1 outboard, the hull resistance can be rapidly increased. Therefore, the acceleration can be reduced over time without changing the rotational speed of the propeller. Since the rotational speed of the propeller does not change, the strength of the propeller's wake hardly changes. Therefore, the rudder force remains unchanged, and the turning resistance of the hull decreases in proportion to the square of the acceleration, which doubles the rudder effectiveness (U0/U) and improves turning performance.

Uo: Ship speed when the deceleration plate is not activated U1: Acceleration when the deceleration plate is activated In addition, in order to avoid a reduction in ship speed due to the deceleration plate 1, the number of rotations of the propulsion device is set to n. If it is increased to +n2, the ship speed will not change, so the turning resistance of the ship will not change, but the rudder force will increase (n2/
no)", and the turning performance is also improved.

(Second Embodiment) In FIG. 4, reference numeral 7 denotes a notch provided in the vertical direction on the starboard and starboard sides of the central portion of the hull, the planar shape of which is fan-shaped.

Reference numeral 5 denotes a speed reduction plate, whose center portion is rotatably attached to a hinge 6 provided at a corner of the notch 7. The deceleration plate 5 is a hydraulic piston 8 or a drive device such as steam, as shown in Fig. 5(a).
It is possible to rotate 90 degrees between a position where the notch 7 is watertightly covered as shown in FIG. Reference numeral 9 denotes a step portion provided so that when the deceleration plate 5 covers the cutout portion 7, it is flush with the gunwale side.

Also in this embodiment, two or more pairs of deceleration plates 5 may be provided on both sides.

1) When stopping or decelerating, reduce the rotation of the propulsion device, or switch to stop or reverse, rotate the deceleration plates on both sides in the direction of the arrow in Figure 5 (a), and extend the deceleration plate 5 outboard. put out. The hull resistance is
This plate 5 causes a sudden increase in deceleration, making it possible to significantly shorten the stopping distance of the ship in an emergency stop.

2) When improving turning performance, also in this case, the reduction plate 5 is extended outboard. The speed reduction plate 5 can rapidly increase the hull resistance and significantly reduce the ship speed without changing the rotational speed of the propulsion device. However, since the rotational speed of the thruster remains unchanged, the strength of the wake of the thruster remains almost unchanged. Therefore, the rudder force remains unchanged, and the turning resistance of the hull decreases in proportion to the square of the ship's speed, and as in the case of the first embodiment, the forward movement is (Uo/U,
), which improves turning performance.

U,: Acceleration when the deceleration plate is not activated U,: Vessel speed (effect) when the deceleration plate is activated A deceleration plate that can be moved in and out vertically and laterally or rotated is installed on the side of the ship, and can be moved laterally when necessary. This not only improves the ship's stopping performance, but also improves rudder effectiveness even in shallow waters, making it possible to further improve turning performance.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a ship according to the present invention. Figure 2 is a detailed sectional view of the section shown by the ■ arrow in Figure 1.
shows the state when it is stored, and FIG. 2(b) shows the state when it is extended. Figure 3 is a front view seen from the bow side. FIG. 4 is a plan view of the second embodiment. FIG. 5 is a detailed view of the section viewed from the arrow ■ in FIG. 4, where FIG. 5(a) shows a state in which the notch is closed, and FIG. 5(b) shows a state in which the notch is extended laterally. Figure 6 is a front view seen from the bow side. Figure 7 is a comparison diagram of turning tracks in shallow water and deep water. FIG. 8 shows three examples of known deceleration assist devices. In the figure; S ship 1 deceleration plate 2 groove 3 roller 4 hydraulic piston 5 deceleration plate
6 Hinge 7 Notch 8 Hydraulic piston 9 Step part - Applicant Sumitomo Heavy Industries, Ltd. Sub-Agent Patent attorney Isamu Ohashi 7 ~ ■ Revised Schiff (

Claims (1)

[Scope of Claims] 1) A ship of the type in which the rudder is placed behind the propulsion device, characterized in that a speed reduction plate is provided on both sides of the ship that can be moved in and out vertically and laterally by a hydraulic device. reduction steering device. 2) In a type of ship in which the rudder is placed behind the propulsion unit, a notch with a fan-shaped planar shape is provided in the vertical direction on the side of the ship, a reduction plate is hinged to the corner of the notch, and the reduction plate is stretched vertically. A deceleration steering device for a ship, characterized in that it is rotatable between an extended position and a position covering a fan-shaped cutout.