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KR-102963991-B1 - Shaft seal system for ship's azimuth thruster

KR102963991B1KR 102963991 B1KR102963991 B1KR 102963991B1KR-102963991-B1

Abstract

A shaft seal system for a swivel propeller of a ship according to an embodiment of the present invention is applied to a swivel propeller comprising: a steering rotation shaft extending outward from a hull; a swivel body coupled to the steering rotation shaft and rotating together with the steering rotation shaft, having a receiving space formed inside; a motor provided in the receiving space of the swivel body, having a driving rotation shaft extending outward through the swivel body; and a propeller coupled to the driving rotation shaft. The shaft seal system comprises: a shaft seal housing disposed around the driving rotation shaft so that the driving rotation shaft passes through it, having one side coupled to the swivel body, and forming a space between the circumference of the driving rotation shaft and an inner surface; a plurality of seals spaced apart along the length of the driving rotation shaft in the space and shielding the space between the driving rotation shaft and the inner surface of the shaft seal housing; and an oil tank supplying oil to the space located between the plurality of seals. It includes an accumulator that supplies pressure to the oil tank; wherein the oil tank and the accumulator are positioned in the receiving space of the swivel body.

Inventors

  • 조범석
  • 권순일
  • 윤배광

Assignees

  • 주식회사 케이티이

Dates

Publication Date
20260512
Application Date
20231226

Claims (5)

  1. A shaft seal system (1) for a swivel propeller of a ship, which is applied to a swivel propeller (2) comprising: a steering shaft (10) extending outward from the hull; a swivel body (20) coupled to the steering shaft (10) and rotating together with the steering shaft (10) and having a receiving space (21) formed inside; a motor provided in the receiving space (21) of the swivel body (20) and having a driving shaft (35) extending outward through the swivel body (20); and a propeller (40) coupled to the driving shaft (35). A shaft housing (100) disposed around the drive rotation shaft (35) so that the drive rotation shaft (35) passes through it, with one side coupled to the pivoting body (20), and forming a space (110) between the circumference of the drive rotation shaft (35) and the inner surface; At least three or more seals (500) spaced apart along the length of the drive rotation shaft (35) in the space portion (110) and shielding the space between the drive rotation shaft (35) and the inner surface of the shaft seal housing (100); An oil tank (200) that supplies oil to the space (110) located between a plurality of the seals (500); It includes an accumulator (300) that supplies pressure to the oil tank (200); The above space section (110) is divided into a plurality of partial space sections (111, 112, 113) from the propeller (40) side to the rotating body (20) side by a plurality of seals (500), and The seal (500) comprises a seal body (501) fixed to the inner surface of the shaft housing (100), and a seal extension (502) extending from the seal body (501) toward the driving rotation shaft and contacting the driving rotation shaft. All of the plurality of the above seals (500) are applied in a shape in which the seal extension (502) is bent toward the propeller (40), and In the above-mentioned shaft housing (100), an oil supply path through which oil from the oil tank (200) is supplied to the space (110) and an oil recovery path through which oil from the space (110) is recovered to the oil tank (200) are formed. One side of the oil supply path is in communication with the oil tank (200), and the other side is in communication with the partial space (111, 112, 113) formed between the plurality of seals (500) that is closest to the pivoting body (20). One side of the oil recovery path is in communication with the oil tank (200), and the other side is in communication with the partial space (111, 112, 113) formed between the plurality of seals (500) that is closest to the propeller (40). Characterized by the fact that, due to the supply pressure of the oil supplied to the space section (110), the seal extension section (502) of the seal (500) and the driving rotation shaft (35) are separated between the oil supply path and the oil recovery path, and oil movement occurs between the plurality of the partial spaces. Shaft seal system for a ship's slewing propeller.
  2. In Article 1, The above accumulator (300) is characterized by supplying a pressure such that an oil pressure 0.2 bar to 0.3 bar lower than the seawater pressure applied to the space (110) can be formed and maintained in the space (110). Shaft seal system for a ship's slewing propeller.
  3. In Article 1, A plurality of the above-mentioned partial spaces (111, 112, 113) are, A first partial space (111) located closest to the propeller (40) and open toward the propeller (40) to allow seawater to flow in; A third partial space (113) located closest to the side of the pivoting body (20); It includes a second space (112) located between the first partial space (111) and the third partial space (113). A plurality of the above seals (500) are, A first seal (510) partitioning the space between the first partial space (111) and the second partial space (112); A second seal (520) partitioning the space between the second partial space (112) and the third partial space (113); It includes a third seal (530) that partitions the space between the third partial space (113) and the receiving space (21) of the pivoting body (20); The other side of the above oil supply path is connected to the third partial space (113), and The other side of the oil recovery path is characterized by being in communication with the second partial space (112). Shaft seal system for a ship's slewing propeller.
  4. In Article 1, The above oil tank (200) and accumulator (300) are characterized by being placed in the receiving space (21) of the above-mentioned rotating body (20). Shaft seal system for a ship's slewing propeller.
  5. In Article 4, A steering shaft housing (700) positioned around the steering shaft (10) so that the steering shaft (10) passes through it, with one side connected to the hull, and forming a steering space (710) between the circumference of the steering shaft (10) and the inner surface; A plurality of steering side seals (800) spaced apart along the length of the steering rotation axis (10) in the steering side space (710) and shielding the space between the steering rotation axis (10) and the inner surface of the steering side shaft housing (700); A steering oil tank (250) that supplies oil to the steering space (710) located between the plurality of steering seals (800); It includes a steering accumulator (350) that supplies pressure to the steering oil tank (250) above, and The above steering side oil tank (250) and steering side accumulator (350) are characterized by being disposed in an axial space (15) formed inside the steering rotation shaft (10). Shaft seal system for a ship's slewing propeller.

Description

Shaft seal system for ship's azimuth thruster The present invention relates to a shaft seal system for a slewing propeller of a ship. During navigation, a ship is steered by the rudder. In conventional ships, the propeller and the rudder are separate, each performing a distinct role. Compared to this conventional steering method, modern ships frequently utilize slewing propellers as the primary propulsion system. Slewing thrusters combine propulsion and steering functions without a separate steering device, and representative examples include pod-type thrusters and rim-type thrusters. For example, a pod-type thruster has a swivel body coupled to a steering shaft extending from the hull, and is equipped with a power unit for driving a propeller within the swivel body, and obtains propulsion for the ship by driving the propeller with the power of the power unit. Since this type of slewing propeller does not require a propeller shaft running across the lower hull, it offers a great degree of freedom in the layout of the engine room. Furthermore, because it can rotate horizontally according to a steering device installed within the hull, it does not require a separate rudder mechanism, resulting in a simple propeller and rudder structure with the advantage of low vibration and noise. Meanwhile, when a propulsion structure is applied to a ship that rotates an external propeller using a power unit, including a slewing thruster, seawater may enter the hull through gaps between the propulsion structures, and a shaft sealing system is required to prevent this. In this regard, the prior art Korean Registered Patent Publication 10-1384120 B1 discloses a stern tube seal device installed in the stern tube of a ship through which the rotating shaft of a power device passes to prevent seawater from entering the engine room. Generally, a shaft sealing system comprises a sealing device, such as the sealing device of the prior art, an oil tank that supplies oil to the sealing device, and an accumulator that supplies pressure to the oil tank. When this shaft sealing system is applied to a vessel equipped with a slewing propeller, the sealing device is placed in the slewing propeller, while other components such as the oil tank and accumulator are placed in the engine room formed in the hull due to spatial constraints. However, in the case of conventional shaft seal systems applied to slewing propellers, the sealing device and the oil tank are located in separate spaces, making it difficult to configure the oil passage and causing difficulties in installation and maintenance work. Therefore, a new type of shaft seal system suitable for slewing propellers is required. Figure 1 is a drawing showing a conventional shaft seal system applied to a slewing propeller. FIG. 2 is a drawing showing a shaft seal system for a slewing propeller of a ship according to an embodiment of the present invention. FIG. 3 is a drawing showing the oil passage of a shaft seal system for a slewing propeller of a ship according to an embodiment of the present invention. FIG. 4 is a drawing showing the internal structure of the shaft seal housing of a shaft seal system for a slewing propeller of a ship according to an embodiment of the present invention. FIG. 5 is a drawing showing the configuration of the shaft seal system for a slewing propeller of a ship according to an embodiment of the present invention applied to the steering rotation axis side. FIG. 6 is a drawing showing the internal structure of a steering shaft housing according to an embodiment of the present invention. Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings. However, the concept of the present invention is not limited to the presented embodiments, and other inventions that are inferior or other embodiments included within the scope of the concept of the present invention can be easily proposed by adding, changing, or deleting other components. Figure 1 is a drawing showing a conventional shaft seal system applied to a slewing propeller. Referring to FIG. 1, the swivel thruster (2) is equipped on the hull (3) and simultaneously performs the roles of propulsion and steering to propel the ship, and generally includes a steering shaft (10), a swivel body (20), a driving device (30), and a propeller (40). The steering shaft (10) is rotatably installed at the bottom of the hull (3) and is configured to rotate by steering by the ship's pilot. The steering shaft (10) is configured to rotate using a vertically extended Y-axis as the axis of rotation. The above-mentioned pivoting body (20) is fixedly coupled to the lower end of the steering rotation axis (10) and is configured to rotate together with the steering rotation axis (10). The above driving device (30) is intended to provide rotational power for the propeller (40) and can be applied as various devices capable of generating rotational power, for example, as a motor.