JPS62500515A - marine propeller - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Title of invention Marine propeller Background of the invention (1) Field of invention The present invention relates to a marine propeller. Here the term "propeller" shall include marine propellers and similar propulsion units.

(2) Conventional technology Conventional propellers are mounted on bosses and selected to best suit the intended application. It has two or more blades set at pitch angles. The propulsion force is dissipated into the surrounding water. As the propeller diverges, it produces a divergent cone of thrust which reduces the efficiency of the propeller. Furthermore, propellers consume potential propulsive energy above the waterline, especially at high speeds. Produces a "cocktail" or "rooster tail" spray indicating that the divergence The effect of the conical shape can be achieved by covering the propeller with a shroud or by surrounding it with links. can be partially removed, but these create increased turbulence and reduce drag. Accept the increase. Finally, the known propeller is capable of reversing the ship on which it is attached. can generate very little reversing force that can be used to brake or .

Various types of propellers have been proposed. For example, US Pat. No. 2,087,243 The book (Mr. Caldwell) states that the radial height along the propeller is concentrated at one point. A propeller is disclosed having a forward portion of each blade tilted forward. The rear part is tilted backwards, and the joining line between the boss and the blade is aligned at a constant pitch. The pitch of the blade is made into a regular spiral, and the peripheral pitch of the blade is larger than the peripheral pitch of the joining line. It's a comb. British Patent No. 8568 of 1909 (Mr. Marks) The peripheral pitch of the blade increases along the propeller, and the radial height of the blade increases along the propeller. It is disclosed that the height increases along the propeller.

In fact, these propellers overcome the technical problems of the known propellers mentioned above. It wasn't enough to solve it.

The purpose of the present invention is to generate greater propulsive force than conventional propellers with the same dimensions as conventional propellers. The aim is to provide propellers that can

Another object of the invention is to generate large braking forces, e.g. or up to 50% reversing force. Our goal is to provide a propeller that can.

Still another object of the present invention is to generate a propulsive force in a converging conical shape with less turbulence. It is to provide Lopera.

In one embodiment of the present invention, a marine propeller includes a boss connectable to a drive shaft; It has a plurality of blades attached to the boss, and each blade has a tip part and a central part. and a rear end portion, and a boss between at least the central portion and the rear end portion of the blade. The pitch of the joining line between the two is increased along the boss.

The tip of each blade is slanted forward relative to the boss, and the rear end of each blade is The part is inclined towards the rear with respect to the boss. Middle part of the central part of the blade , that is, at an angle of about 70 to 110 degrees from the tip, it is substantially in contact with the boss. It is stretched in the radial direction.

Peripheral pitch of a blade increases from the center or mid-section of the blade to the trailing edge. It's a big deal.

The radial height of the blade increases from the tip to the middle; The radial height of the blade is maximized at the trailing edge. The direction decreases toward the rear end portion.

In the side view, the tip of each brake has the shape of an airfoil, and the rear end The part is aerof oil that creates a low pressure area in the water that the propeller is passing through. It has a shape.

Each blade spans an angle of 180° to 270°, preferably about 220°. and extends around the boss.

Brief description of the drawing Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

Fig. 1 is a side view of a propeller according to the invention, and Fig. 2 is partially lined with dotted lines for clarity. The rear end view of the propeller shown in Figure 3 is the plane of the blade cut from the plate before manufacture. Figures 4 to 9 (cross section of the blade taken along lines 4-4 to 9-9 in Figure 2) It is a diagram.

BEST MODE FOR CARRYING OUT THE INVENTION The propeller 10 has a boss 11 that is directly engaged with the ship's drive shaft. A shouldered drive boss can be installed to engage the drive shaft.

A pair of blades 12 are provided around the boss 11 at an angle of about 2200, and each blade 12 has a tip portion 13, a central or intermediate portion] 4, and a rear end portion 15. . The tip portion 13 of each blade 12 has a bent tip that increases the height of the outer circumference; The edges are relatively rounded compared to the beveled edges of conventional propellers. destination The end portion 13 is inclined forward with respect to the boss 11 (see Figures 4 and 5). (see), the form of airfoil to form a low-pressure area on the surface of that part of the blade. The shape is bent like a funnel.

The central portion 14 of the propeller 10 is at an angle of about 706 to 90 degrees of the blades 12. It begins and reaches the maximum radial height of the blade at an angle of about 90° to 1]o°.

The central portion 14 has an inclination relative to the boss 11 from a forward inclination (see FIG. 5). substantially radially (see Figure 6) and rearwardly inclined (Figure 7). ) is gradually changing.

The radial height of the blade 12 gradually increases from the central portion 14 to the rear end portion 15. and the trailing end portion 15 of the blade is sloped rearwardly with respect to the boss 11. (As shown in Figures 8 and 9).

The trailing end portion 15 is moved at high speed to create a low pressure area in front of that portion of the blade 12. It has the shape of an airfoil in side view, with its low pressure area extending beyond the other blade 12. It is adjacent to and downstream of a low pressure area formed on the rear surface of end portion 13.

Adjust the pitch of the joining line 16 of the blade 12 to the boss 11 along the propeller. At least the central portion 14 to the rear end portion 15 to form a throat that branches between the two ends. , for example along the boss over a range of angles from 70 to 110 degrees to 2206 degrees. It is increased.

In various tests, the propeller according to the invention has been shown to collect very small droplets even at high speeds. Generates propulsive force in the shape of a bundle cone, producing greater propulsive force than conventional propellers with the same diameter. It was found that this occurs. (In one test, a 40 cm diameter profile of the invention When the propeller was installed on the boat to replace the damaged propeller with a diameter of 63 cm, the generated the same propulsion force. ) The performance of the propeller of the present invention is that it sucks water into the propeller. Improved by the shape of the airflow oil on the blades that tend to The branching throat of the blade increases the pitch angle of the joining line of the blade to the boss. To prevent fluid choking from occurring in the ropeler.

Due to the airflow oil shape of the blade at the inlet and outlet to the bifurcated throat. The low pressure area created by the propeller helps drain water past the propeller.

In tests, the propeller has been shown to provide increased forward power as well as reverse up to 50% of the forward power. It showed progress. This reverse force is conventional, which has a reverse force in the range of 0% to 10% of the forward force. much larger than that of the propeller. Improved reversing force inside the propeller when reversing This is thought to be due to the airfoil shape of the blade, which forms a low-pressure area.

The propeller can be cast into the desired shape and can be made of steel or aluminum plate. It can also be manufactured with a blade formed by the same method.

In order to easily understand the manufacture of propellers, reference will be made to FIG.

an outer radius 17 approximately equal to the maximum radial height of the blade (central portion 14); Cut the annular metal piece so that it has an inner radius 18 that is slightly larger than the outer radius of the boss 11. take away

Remove part of the board leaving a blade at an angle of approximately 220° around the boss. destination At approximately 90" from the edge (i.e. at point 19), the inner radius of the plate is 14 to the rear end portion 15, and its effective inner radius 18a is expressed as: where r is the inner radius of the body portion (shown by line 18), R is the center and and the effective inner radius of the trailing end portion (indicated by line 18a), a is the radius increase ratio, and b is the point 19 An angular distance from the trailing edge that is less than the angular distance from the leading edge (e.g. 90°) , C is an angle coefficient (for example, 4o to 45°).

Therefore, at the trailing edge of the 220° blade, the effective inner The effective radius of radius R is approximately 1.6 mm every 456 around the boss from point 19 ( 1716 inches), it is larger than the radius of the tip by about 4 to 45 mm. be.

The central portion 14 is attached to the boss 11 and the blade 12 extends toward the rear edge of the boss. It is wrapped around it in stages. The effective inner radius R is relative to the outer radius of the boss 11. The blade engages the boss and is pulled to pull the blade rearward. must be stretched. This simultaneously reduces the peripheral height of the blade and Increasing the peripheral pitch and increasing the backward slope of the blade towards the trailing edge increase the pitch of the joining line between the boss and the blade (see Figures 6 to 9). (see figure). The tip of the blade can be attached to the boss at the tip of the tip edge. It is bent forward like this. The forward slope of the blade is shown in Figures 4 and 5. It is.

Comparative test using a conventional propeller and the propeller of the present invention in the same ship engine Experiments showed the following improvements in the propeller of the present invention.

1) When the throttle is pressed fully open, the propeller of the present invention is not at full speed. drives the ship and runs to full speed, and the ship is driven by a conventional propeller. Reach full speed at distance 3.

2) Be able to increase the maximum speed of the ship by 10-30%.

3) In rough waves, the propeller does not emerge upwards from the water and is overlaid. There is no tendency to

4) At speed, ships tend to glide over the water. In other words, the stern is underwater. It's higher than that.

5) When making a sharp turn, the ship is tilted like an airplane, and the stern is likely to skid. There is no fault.

6) When the engine is stopped, a strong braking action is observed, and when reversing, Strong reversing propulsion is obtained (and water is pulled over the stern when the vessel is reversed). (You can be kicked out.)

7) The "cocktail" effect is reduced or minimized, with little water behind the propeller. It is "homogeneous" with kana disorder.

8) Water seems to be sucked into the propeller by airf oil on the blades. It appears to be moving before entering the propeller.

9) The rounded peripheral edge of the blade's tip will be removed when it hits a rock or other submerged object. There is no risk of damage due to chipping or braking.

The specific shape of the propeller, e.g. number of blades, shape, diameter, length, pitch and The slope can be selected to suit the particular intended application.

Various modifications and changes: departing from the scope of the invention as defined in the claims. This can be done in the embodiments described above.

international search report

Claims (1)

[Claims] 1) The above-mentioned device having a boss connectable to the drive shaft, a tip portion, a center portion and a rear end portion. In a marine propeller with multiple blades attached to a boss, the boss and blades The pitch of the joining line between at least the central part and the rear end part of the board is adjusted along the boss. A marine propeller characterized by an enlarged propeller. 2) Tilt the tip of each blade backwards with respect to the boss, and The first claim is characterized in that it extends substantially radially with respect to the base. Marine propeller. 3) Adjust the pitch around the blade from the center of the blade to the rear end along the propeller. The ship according to claim 1 or 2, characterized in that the ship is increased by: Propeller for. 4) Increase the radial height of the blade from the tip to the center, The radial height was maximized at the end and then decreased towards the rear end. A marine boat according to any one of claims 1 to 4, characterized in that: Lopera. 5) The tip of each blade is shaped like airfoil, and the rear end is a propeller. The airflow oil is shaped to create a low pressure area in the water to drain the water. The ship according to any one of claims 1 to 4, characterized in that: Marine propeller. 6) To prevent the propeller from being choked by water, connect the throat of the propeller to the branch. Claims 1 to 5 are characterized in that the blades are formed between the blades along the The marine propeller according to any one of paragraphs. 7) Start forming the center part at an angle of 70 to 110 degrees from the tip edge of the blade. For ships according to any one of claims 1 to 6, characterized in that propeller. 8) A boss that can be connected to the drive shaft, and a boss that has a tip portion, a center portion, and a rear end portion. In a marine propeller comprising a plurality of blades attached to the The tip of each blade is gradually inclined forward with respect to the boss, and the tip of each blade is approximately The rear end is radially transitioned to the middle section and then sloped backwards relative to the boss. The peripheral pitch of the blade is increased along the boss from the tip to the rear end. , reducing the radial height of the blade from the middle section to the rear end, increasing the height of the blade from the tip and The rear end of the propeller is equipped with an air vent that creates a low-pressure area underwater to drain water to the propeller. At least the central and rear end portions of the boss and the blade, The pitch of the joining line is increased along the boss. The marine propeller according to item 1. 9) Transfer the Aerof oil on the tip of the blade to the Aerof oil on the rear edge of the blade. It is placed on the opposite side of the blade to the oil, and the airf oil on the tip is blocked. The valve is designed to operate to create a low pressure area at the inlet of the branch throat formed between the ports. A low pressure area is provided at the outlet of the throat which diverts the airflow oil on the rear end section. Claim 8 is characterized in that the invention is arranged to operate in such a way that the Marine propeller.