JPH1129093A - Entrained fishing net automatic removing type marine propeller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To remove a fishing net entrained by a propeller at the stern, easily and completely and moreover automatically. SOLUTION: In a marine propeller, a slope face 6 of recessed curve shape formed in such a way that an outer diameter is smoothly increased frontward is provided at the outer peripheral surface of a propeller boss, in front of a blade root part of a propeller blade 8, and fishing net cutting linear protrusions 7 obliquely intersecting a rotating direction of the propeller are provided on the propeller outer peripheral surface between the slope face 6 and the blade root part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a marine propeller provided on a stern, and more particularly to a marine propeller capable of automatically removing a fishing net involved in a stern.

[0002]

2. Description of the Related Art In general, as a cause of an accident or a trouble during a voyage of a ship, there is an accident involving a fishing net getting into a propeller. There are mainly two accidents involving fishing nets.
One is an accident in which fishing nets cling to propellers and cause damage to propeller wings. The other is an accident in which a fishing net wraps around the portion covering the stern tube seal from the boss of the propeller, causing damage to the propeller boss and the hull stern. Such an accident may also affect the rotation of the propeller and cause troubles on the main engine.

[0003] In order to prevent such accidents involving the fishing net, a device called a net protector may be attached to the marine propeller. However, this device can only deal with the fishing net wound around that portion, and the propeller blade or other propeller wings can be used. There is a possibility that fishing nets remain in the area and cause accidents.

[0004]

SUMMARY OF THE INVENTION Accordingly, the present invention provides a marine propeller with an automatic removal type fishing net which can easily, completely and automatically remove a fishing net caught in a propeller at the stern. The task is to

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a marine propeller of the present invention is provided with a propeller boss mounted on a rear end of a propeller shaft at a stern and radially radiated from the propeller boss. In the marine propeller composed of a propeller blade protruded to the, on the outer peripheral surface of the front end of the propeller boss ahead of the blade root of the propeller blade,
A concavely curved slope surface formed so as to smoothly increase the outer diameter toward the front is provided, and on the outer peripheral surface of the propeller boss between the slope surface and the blade root portion,
It is characterized in that a number of linearly protruding projections are erected so as to intersect obliquely with the propeller rotation direction.

In the above-described marine propeller of the present invention, when the fishing net is caught in the propeller rotating at the stern during navigation, the fishing net flows in from the front, and comes into contact with the outer peripheral surface of the propeller boss at the front end side of the propeller boss. Although it is about to wind, the fishing net is guided by the concave curved slope surface in the propeller boss, reaches the many protrusions, and is efficiently cut by the protrusions under tension. It starts to flow backward.

[0007] At this time, since the projections linearly protrude so as to cross the propeller rotation direction obliquely, the cutting action of the fishing net by the projections can be efficiently performed.

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view showing an essential part of a marine propeller for automatically removing a entangled fishing net according to an embodiment of the present invention. FIG. 2A shows an example of a projection provided on the outer peripheral surface of the propeller boss, FIG. 2A is a plan view thereof, FIG. 2B is a view taken along the line BB of FIG. 2A, and FIG. FIG. 3 is a view taken in the direction of arrows CC in FIG. 2 (a), and FIG. 3 shows another example of a projection provided on the outer peripheral surface of the propeller boss of the marine propeller in FIG.
3 (a) is a plan view thereof, FIG. 3 (b) is a view taken along a line BB of FIG. 3 (a), FIG. 3 (c) is a view taken along a line CC of FIG. 3 (a), and FIG. FIG. 2 is a longitudinal sectional view of a main part of a stern of a ship provided with the marine propeller of FIG. 1.

As shown in FIGS. 1 and 4, a propeller boss 1 mounted on the rear end of a propeller shaft 3 at the stern 2 and a propeller blade 8 protruding radially from the propeller boss 1 are formed. In the marine propeller, on the outer peripheral surface of the front end portion of the propeller boss 1 ahead of the blade root portion of the propeller blade 8, a concavely curved slope surface 6 formed so as to increase its outer diameter smoothly forward is provided. Have been.

On the outer peripheral surface of the propeller boss 1 between the slope surface 6 and the blade root of the propeller blade 8, a number of linearly projecting protrusions 7 are erected so as to obliquely intersect the propeller rotation direction. ing. 2 (a), 2 (b) and 2 (c) show an example of the projection 7, in which the tip of a crescent-shaped object has a sharp-angled blade over its entire length. In the case of a clockwise propeller, the mounting direction is a mounting direction that is rightward downward toward the stern 2 when viewed from a direction perpendicular to the rotation axis.

In the example of the projection 7 shown in FIGS. 3 (a), 3 (b) and 3 (c), the projection 7 is formed as a wedge-shaped blade as a whole, but its mounting direction is the same as in FIG. It is. In addition,
The mounting direction of the protrusions 7 may be a direction that forms a staggered shape.

In the above-described marine propeller of the present embodiment, when the fishing net is caught in the propeller rotating at the stern during navigation, the fishing net flows in from the front, and the propeller boss 1 Although the fishing net attempts to wind around the outer peripheral surface, the fishing net is guided by the concavely curved slope surface 6 of the propeller boss 1 and heads toward a large number of projections 7 behind the fishing net. The projection 7 cuts off and flows backward. At this time, since the projection 7 linearly projects so as to cross the propeller rotation direction at an angle, the fishing net can be efficiently cut by the projection 7.

As described above, in the marine propeller of this embodiment, the fishing net is guided rearward by the slope surface 6 shown in FIG. Without damaging the seal cover 5 and the like, the fishing net to be wound around is efficiently and automatically removed by the cooperative action of the slope surface 6 and the projection 7 of the propeller boss 1. In addition to the necessity of the net protector attached to the outer periphery, there is an advantage that machining for mounting the protector can be omitted.

[0014]

As described in detail above, the following effects can be obtained by the marine propeller of the present invention. (1) When a fishing net is caught in the propeller rotating at the stern during navigation, the fishing net flows in from the front and tries to wind around the outer peripheral surface of the propeller boss at the front end of the propeller boss. Is guided on the concave slope surface of the propeller boss, and goes to many protrusions behind it,
In a state where the tension is generated, the protrusion is efficiently cut by the projection and flows backward. (2) Since the protrusion protrudes linearly on the outer peripheral surface of the propeller boss so as to obliquely intersect with the propeller rotation direction, the fishing net can be efficiently cut by the protrusion. (3) Since the fishing net to be wound is guided rearward on the slope surface and is subjected to the cutting action by the projection, damage to the stern tube seal and the seal cover in front of the fishing net is prevented. (4) The fishing net to be wound can be easily, completely and automatically removed by the cooperative action of the slope surface and the linear projection, thereby making it possible to remove the conventional net protector or the same. Eliminates machining for mounting the protector.

[Brief description of the drawings]

FIG. 1 is a side view showing a main part of a marine propeller with an automatic entangled fishing net according to an embodiment of the present invention.

FIG. 2 shows an example of a projection provided on the marine propeller of FIG. 1; FIG. 2 (a) is a plan view thereof, FIG. 2 (b) is a view taken along the line BB of FIG. 1 (a), and FIG. The figure is a view taken in the direction of arrows CC in FIG.

3A and 3B show another example of a projection provided on the marine propeller of FIG. 1, wherein FIG. 3A is a plan view thereof, FIG. 3B is a view taken along the line BB of FIG. FIG. c) is a view taken along the arrow CC in FIG.

FIG. 4 is a longitudinal sectional view of a main part of a stern of a ship provided with the marine propeller of FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Propeller boss 2 Stern 3 Propeller shaft 4 Stern tube seal 5 Seal cover 6 Concave curved slope surface 7 Protrusion 8 Propeller blade

Claims (1)

[Claims] 1. A marine propeller comprising a propeller boss mounted on a rear end portion of a propeller shaft at a stern and a propeller blade protruding radially from the propeller boss, ahead of a blade root of the propeller blade. On the outer peripheral surface of the front end portion of the propeller boss, a concavely curved slope surface formed so as to smoothly increase the outer diameter toward the front is provided,
On the outer peripheral surface of the propeller boss between the slope surface and the blade root portion, a number of linearly projecting protrusions are erected so as to obliquely intersect the propeller rotation direction, A marine propeller that automatically removes catching fishing nets.