JP3010485B2 - Sealing device for stern tube for propeller shaft of ship - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seal device for a stern tube for a propeller shaft of a boat such as a leisure boat such as a fishing boat or a fishing boat.

[0002]

2. Description of the Related Art Although a propulsion shaft penetrates outboard through a stern tube, a radial gap is provided between the stern tube and the propulsion shaft. In order to prevent this, a stern tube sealing device is conventionally applied to the stern tube.

[0003] The stern tube sealing device of a relatively small ship secures water tightness by bringing a gland packing into close contact with the peripheral surface of a propulsion shaft, or secures water tightness by adopting a diaphragm type or a bellows type using a rubber material. It has been done.

[0004]

In the conventional stern tube sealing device described above, in the case of using the gland packing, water leakage becomes excessive due to the lapse of use time, or the propulsion shaft wears due to sliding contact of the gland packing. Or the frictional contact of the gland packing causes a large friction to reduce the power transmission efficiency, and the diaphragm or bellows type has a structure that maintains the watertightness mainly by the elastic force of rubber. The problem is that water leakage becomes excessive with deterioration of the rubber, and when the radial displacement during rotation of the propulsion shaft or the change in the deflection angle of the axis increases due to wear of the bearings in the stern tube, watertightness is reduced. There are problems such as difficulty in securing. An object of the present invention is to provide a stern tube sealing device which can solve the above-mentioned problems.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention relates to a two-step upper and lower key step for an end portion of a set body which is attached to a stern tube so as to surround a propulsion shaft. The upper end is locked with the front end of the rubber bellows, and the rear end of the rubber bellows is fitted with a seal ring made of carbon material and fixed to the propulsion shaft via the seal ring. A spring is stretched in a rubber bellows which is substantially co-linear with the seal ring body, and the front end of the spring is engaged with the lower key step of the set body. The seal ring body is pressed against the rotor sheet by the elastic resilience of the rubber bellows and the spring.

At this time, there is an adjusting collar for fixing the rotor sheet to the propulsion shaft, and a movable body having an O-ring on the inner peripheral surface, and the adjusting collar is formed on an inner surface of a flange portion protruding in parallel with the propulsion shaft. A female bolt is provided on the other side, and the movable body is provided with a male screw to be screwed with the female screw of the adjust collar, and the set bolt for appropriately moving on the stern tube by screwing of both screws and fixing the moving position. In the case of a configuration provided with, the pressure contact force can be easily adjusted with respect to the wear of the seal ring body over time.

[0007]

FIG. 1 is an explanatory longitudinal sectional view of the apparatus of the present invention. Reference numeral 1 denotes a propulsion shaft, the right side of which is connected to a propeller blade, and the left side of which is connected to an output shaft of an engine. Reference numeral 2 denotes a set body which is secured to the stern tube via a screw bolt 3 so as to surround the propulsion shaft 1. Here, the upper and lower two-step key steps a and b are formed on the end face of the set body 2 on the side opposite to the stern tube.

Reference numeral 4 denotes a rubber bellows, and a tip p of the rubber bellows 4 is engaged with an upper key step a of the set body 2. Then, a plurality of concave holes 5 (four in the illustrated example) are formed in the opposite side of the rubber bellows,
A seal ring body 6 made of a carbon material is engaged and fixed through the concave hole 5. That is, the seal ring body 6 has an L-shaped cross section of the horizontal part m and the vertical part n as shown in the illustrated example, and a plurality of (four in the illustrated example) corners are provided on the side of the vertical part n that contacts the rubber bellows 4. A body k is formed and engaged with the concave hole 5.

Reference numeral 7 denotes a spring extending toward the inner surface of the rubber bellows 4. The front end of the spring 7 is in contact with the lower key step b of the set body 2, while the rear end is located on the horizontal portion of the seal ring body 6. Rubber bellows 4 that is approximately on the same straight line as m
To be brought into contact with the inner surface of the vehicle. Reference numeral 8 denotes a tightening band for tightening and fixing the front portion of the rubber bellows 4 to a shelf c formed between the upper key step a and the lower key step b of the set body 2. Reference numeral 9 denotes a cylindrical cover which is attached so as to cover the outer peripheral surface of the rubber bellows 4 and is fixed to the set body 2 with a set screw 10.

Reference numeral 11 denotes an O-ring 12 on the inner peripheral surface, and a sliding surface 11a against which the end surface of the horizontal portion m of the seal ring body 6 is pressed by the elastic repulsion of the rubber bellows 4 and the spring 7. Rotor seat, propulsion shaft 1
It is fixed by a set bolt 13 so as to rotate integrally with the main body.

Reference numeral 14 denotes an emergency seal ring provided in the main body of the set body 2.
Is mounted so that there is a gap t between
By pressing a plug 15 attached to the upper surface of the set body 2 in an emergency, the seal ring 14 is brought into press contact with the propulsion shaft 1 so that an emergency seal is performed. In the drawing, reference numeral 16 denotes a water-absorbing plug attached to the set body 2, and a part of the cooling water of the engine portion is caused to flow through the portion into the gap s with the propulsion shaft 1 so as to prevent temperature rise. It is.

FIG. 2 shows another embodiment, which is the same as that of FIG. 1 except that the rotor sheet 11 is divided into two parts. That is, in this embodiment, the rotor seat 11 is fixed to the propulsion shaft 1 with the adjusting collar 11a fixed to the propulsion shaft 1 by an O.
The movable collar 11b is provided with a ring 12 and has a dichotomous structure. In this case, the adjustment collar 11a has a shape of a flanged tray, and a flange body g is formed so as to protrude in parallel with the propulsion shaft 1. Further, a female screw e is engraved on the inner surface thereof.

On the other hand, the movable body 11b has a horizontal stepped portion v on which a male screw f is screwed with the female screw e of the adjusting collar 11a, and a periphery of a vertical portion w with which the seal ring body 6 comes into contact. A plurality of adjustment holes 17 are formed in the head side, and a jig is inserted to rotate the movable body 11b clockwise or counterclockwise to move the movable body 11b in the direction (a) or (b). They are being moved. In addition, 18
Is a set bolt for fixing the movable member 11b provided near the vertical portion w of the horizontal moving portion v, and fixes an appropriate position of the movable member 11b to be moved in the direction (a) or (b). It is something to do.

[0014]

The sealing device of the present invention is constructed as described above. Only the rotor sheet rotates integrally with the propeller propulsion shaft, and the rubber bellows and the seal ring body rotate. Since these do not move, they do not cause problems such as buckling or material rupture due to centrifugal stress against eccentric fluctuation rotation of front and rear, left and right, up and down of the propeller shaft It is. On the other hand, the seal ring body is configured to be pressed not only by the rubber bellows but also by the strong elastic resilience of the spring, so that the pressure contact surface can maintain the proper sliding pressure contact state even at high speed rotation. Becomes

In the present invention, when the seal cylinder body wears out after a long operation, the set bolt of the rotor seat is loosened appropriately and the fixed position is moved to the set body side against the resilience of the spring or the rubber bellows. In this case, the rotor sheet is fixed again with the set bolts, thereby enabling simple continuous use. By loosening the set bolt and inserting the jig into the adjustment hole and turning it counterclockwise, the rotor sheet moves in the direction of arrow (a), and the appropriate press-contact state while replenishing the wear of the seal ring body Is obtained, and more simple and accurate adjustment work can be performed.

The device of the present invention can be mounted relatively easily by removing the conventional gland packing retainer and packing of the stern tube and using the mounting bolts. According to the experiment of the present inventor, it has been found that the sealing property is surely secured by high-speed rotation at a peripheral speed of 7.4 m / sec at a surface pressure of 1.5 kg / cm ² on the sliding surface of the rotor sheet. In particular, the conventional rubber bellows type and diaphragm type use the elasticity of rubber alone, so that elastic stress is eliminated in a long-term compression state, causing a problem in sealing performance. Since the spring is stretched on the pressure contact line of the ring body, it is possible to eliminate the fear of the above problem.

[Brief description of the drawings]

FIG. 1 is a vertical sectional view of the apparatus of the present invention.

FIG. 2 is an apparatus according to another embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Propulsion shaft 2 Set body 4 Rubber bellows 5 Concave hole 6 Seal ring body 7 Spring 8 Tightening band 9 Cylindrical cover 11 Rotor seat 13 Set bolt 14 Emergency seal ring 16 Water-absorbing plug a Key step b Key step

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-8-282592 (JP, A) JP-A-8-230789 (JP, A) JP-A-62-265099 (JP, A) JP-A-62-265099 143793 (JP, A) JP-A-61-232992 (JP, A) JP-A-7-10633 (JP, U) JP-A 5-27358 (JP, Y2) (58) Fields investigated (Int. Cl. ⁷ , DB name) B63H 23/36

Claims (2)

(57) [Claims] 1. A set body, which is attached to a stern tube so as to surround a propulsion shaft, is formed with two upper and lower key steps at an end surface on the side opposite to the stern tube. The front end is locked, a seal ring body using a carbon material is attached to the rear end of the rubber bellows, and the rotor is fixed to the rotor seat fixed to the propulsion shaft via the seal ring body. A spring is stretched in a rubber bellows which is substantially on the same straight line, and a front end of the spring is locked to a lower key step of the set body. A sealing device for a stern tube for a propeller shaft of a ship, characterized by being pressed against a rotor seat. 2. An adjusting collar for fixing a rotor sheet to a propulsion shaft, and a movable body having an O-ring on an inner peripheral surface thereof. The adjustment collar is provided on an inner surface of a flange portion formed to project in parallel with the propulsion shaft. A female screw is provided, while the movable body is provided with a male screw which is screwed with the female screw of the adjust collar, and a set bolt for fixing a moving position on the stern tube by screwing the screw. 2. The sealing device for a stern tube for a propeller shaft of a ship according to claim 1, wherein: