KR-20260062480-A - SINGLE-AXIS COUNTER-RATATING PROPULSION DEVICE OF SHIP

Abstract

In the present invention, a single-axis counter-rotation propulsion device for a ship is disclosed. For example, a single-axis counter-rotation propulsion device for a ship is disclosed, comprising: a forward propeller section including a forward propeller and a forward propeller hub; a rear propeller section including a rear propeller and a rear propeller hub; a propeller shaft section fixed to either the forward propeller hub or the rear propeller hub and connected to another unfixed propeller hub via a hub bearing so as to be able to rotate independently; and a magnet gear section installed on the forward propeller hub and the rear propeller hub, respectively, spaced apart from each other, and rotating in opposite directions according to a magnetic flux path.

Inventors

• 이찬희

Assignees

• 에이치디한국조선해양 주식회사

Dates

Publication Date

20260507

Application Date

20241029

Claims (8)

1. A front propeller section including a front propeller and a front propeller hub; A rear propeller section including a rear propeller and a rear propeller hub; A propeller shaft portion fixed to either the front propeller hub or the rear propeller hub and connected to another unfixed propeller hub via a hub bearing so as to enable independent rotation; and A magnet gear section installed on the front propeller hub and the rear propeller hub, respectively, spaced apart from each other, and rotating in opposite directions according to a magnetic flux path; A single-axis counter-rotation propulsion device for a ship characterized by including
2. In paragraph 1, A single-axis counter-rotation propulsion system for a ship, characterized in that the forward propeller and the rear propeller include a controllable pitch propeller (CPP).
3. In paragraph 1, The above magnet gear section is, A front magnet gear installed on the front propeller hub above; A rear magnet gear installed on the rear propeller hub; and A single-axis counter-rotation propulsion device for a ship, characterized by including a pole piece interposed between the front propeller hub and the rear propeller hub to form a magnetic flux path in the front magnet gear and the rear magnet gear.
4. In paragraph 3, A single-axis counter-rotation propulsion device for a ship, characterized in that each of the above-mentioned front magnet gear and the above-mentioned rear magnet gear has a radial structure in which different magnetic poles are alternately arranged along the circumferential direction.
5. In paragraph 3, A single-axis counter-rotation propulsion device for a ship, characterized in that the speeds of the front propeller and the rear propeller can be adjusted differently depending on the change in the number of pairs of magnetic poles for each of the above-mentioned front magnet gear and the above-mentioned rear magnet gear.
6. In paragraph 3, A single-axis counter-rotation propulsion device for a ship, characterized in that the above-mentioned pole piece comprises a disk having an inner ring and an outer ring, and a plurality of magnetic bodies arranged radially from the center of the disk.
7. In paragraph 3, A single-axis counter-rotation propulsion device for a ship, characterized in that the magnet gear portion is positioned at least at the front and rear of the pole piece and further comprises a surface layer containing an antifouling material.
8. In paragraph 3, A single-axis counter-rotation propulsion device for a ship, characterized in that the magnet gear section further comprises an antifouling film coated on at least one of the surface between the front magnet gear and the pole piece, and the surface between the rear magnet gear and the pole piece.

Description

Single-axis counter-ratting propulsion device of ship The present invention relates to a single-axis counter-rotation propulsion device for a ship. Conventional marine propulsion systems are equipped with a single helical propeller. However, propulsion systems with a single propeller suffer significant energy loss because they cannot utilize the rotational energy of the water flow resulting from the propeller's rotation as thrust. A counter-rotating propeller (CRP) can recover such lost rotational energy as thrust. In a counter-rotating propeller, two propellers installed on the same axis rotate in opposite directions to generate thrust. The rear propeller recovers the rotational energy of the fluid passing through the front propeller by rotating in the opposite direction. Therefore, it can achieve higher thrust performance compared to a propeller with a single propeller. However, since the counter-rotation propulsion system includes a counter-rotation mechanism that implements the opposite rotation of two propellers and a hollow shaft, it is relatively difficult to manufacture and install, and a high level of technology is required to ensure stable operation while maintaining reliability. Conventional counter-rotation propulsion systems include dual-shaft systems with gearboxes, single-shaft systems with mechanical bevel gears, and dual-shaft systems with magnetic gears. First, in the case of a dual-shaft system with a gearbox, the conventional CRP (Counter-Rotating Propeller) shaft system typically has a structure in which two actuators rotating in opposite directions are connected to each shaft to rotate the inner shaft and the outer shaft in opposite directions, or even if only one actuator is used, an expensive gearbox is applied to rotate the inner shaft and the outer shaft in opposite directions. However, in the case of a dual shaft system composed of inner and outer shafts like this, not only are there difficulties in installation, maintenance, and repair, but there are also disadvantages such as the need for a complex dual shaft system and a complex and expensive reduction gearbox. Next, in the case of a single-shaft system using mechanical bevel gears, although it has been simplified into a single shaft system, there are issues regarding mechanical complexity and durability resulting from the application of mechanical bevel gears. To address this, a structure has been proposed in which the rear propeller is rotated on a single shaft and the front propeller is reversed by applying bevel gears, but the propulsion system with such improved structure can cause the bevel gears, which are vulnerable to shock, to break and the system to break due to high thrust and changes in eccentricity caused by operating conditions. Therefore, it is difficult to ensure reliability in terms of durability and stability, and there is a problem that it cannot be applied to ships that require a long lifespan of more than 20 years and high safety reliability. Finally, in the case of a dual-shaft system equipped with magnetic gears, while it has the advantage of improving the durability of existing mechanical systems by utilizing magnetic gears with enhanced mechanical durability, it still faces limitations due to the requirement to apply a complex dual-shaft system consisting of an inner and outer shaft. Consequently, difficulties in installation, maintenance, and repair persist, and there is also the disadvantage of low propulsion efficiency resulting from the need to rotate the entire dual shaft via magnetic gears. FIG. 1 is a drawing showing the overall configuration of a single-axis counter-rotation propulsion device applied to a ship according to an embodiment of the present invention. FIG. 2 is a diagram showing the configuration and counter-rotation of a front magnetic gear and a rear magnetic gear according to an embodiment of the present invention. FIGS. 3 and 4 are drawings illustrating the configuration of a first type of single-axis counter-rotation propulsion device according to an embodiment of the present invention and the thrust direction adjustment function through the control of the pitch angle of the propeller. FIGS. 5 and 6 are drawings illustrating the configuration of a second type of single-axis counter-rotation propulsion device according to an embodiment of the present invention and the thrust direction adjustment function through the control of the pitch angle of the propeller. Hereinafter, a single-axis counter-rotation propulsion device for a ship according to an embodiment of the present invention will be examined in detail with reference to the attached drawings. Prior to this, terms and words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, but should be interpreted in a meaning and concept consistent with the technical spirit of the invention, based on the principle that the inventor can appropriately define the concep