JP2003191893A - Bearing structure for drive shaft for vessel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce frequency of grease supply maintenance for a drive shaft bearing part. <P>SOLUTION: A drive shaft 22 for driving an impeller is rotatably supported on a hull via a bearing member 52. A grease reservoir 22f constituted of a ring-shaped recessed groove is provided on a facing surface 22e with the bearing member 52 in the drive shaft 22. A grease supply port 51d is provided on a bearing body 50 for storing the bearing member 52. Grease can be filled into a bearing chamber 51 and the grease reservoir 22f without extracting the drive shaft 22 from the bearing body 50. <P>COPYRIGHT: (C)2003,JPO

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a marine drive shaft bearing structure. 2. Description of the Related Art As a conventional bearing structure for a marine drive shaft, there is known a structure as shown in FIG. 7 (Japanese Patent Laid-Open No. 7-112697). In the figure, reference numeral 1 denotes a drive shaft. A driven side coupler 2 connected to a drive side coupler (not shown) of the engine is fixed to a front end of the drive shaft, and an impeller (not shown) is fixed to a rear end of the drive shaft. Is transmitted to the impeller to rotate the impeller. The bearing structure has a bearing body 4 that rotatably supports the drive shaft 1 with respect to the hull 3. The bearing body 4 includes a bearing member (a ball bearing is shown) for rotatably supporting the drive shaft 1, a bearing chamber 6 for accommodating the bearing member 5, and both sides of the bearing member 5 (back and forth in the axial direction). Outer surface of the drive shaft 1 (the outer surface of the sleeve 1 ′ that rotates together with the shaft 1) 1 a
Sealing members 7, 7 that partition the bearing chamber 6 by contact with
And In such a bearing structure, usually, when assembling the bearing body 4 to the hull 3, the bearing chamber 6
Assemble with grease filled. Bearing member 5
This is for the purpose of smooth rotation. In a state where the bearing body 4 and the drive shaft 1 are assembled to the hull 3, as described above, the seal members 7, 7 are attached to the drive shaft 1.
The bearing chamber 6 is basically in an airtight state because the bearing chamber 6 is partitioned by contacting the outer peripheral surface 1a of the drive shaft 1a. Therefore, unless the drive shaft 1 rotates (therefore, the ship runs), the bearing chamber 6 is basically closed. It is unlikely that the grease filled in 6 leaks out of the bearing chamber 6. However, in practice, the drive shaft 1 is rotated by the driving of the engine, the impeller is rotated, and the ship is navigated, so that the rotation of the drive shaft 1 and the bearing member 5 The temperature in the bearing chamber 6 rises. When the temperature in the bearing chamber 6 rises,
The grease or air in the bearing chamber 6 expands. According to the above-described conventional bearing structure, since the end 7a of the seal member 7 is arranged toward the outside of the bearing chamber 6, when grease or air in the bearing chamber 6 expands beyond a certain level, The gap between the contact portion 7b of the seal member 7 formed on the outer peripheral surface 1a of the shaft 1 and the outer peripheral surface 1a of the shaft formed by the deformation of the seal member 7 due to the increase in the internal pressure of the bearing chamber 6 causes Grease or air leaks out of the room. Therefore, even if the grease or the air in the bearing chamber 6 expands, it is possible to prevent the seal member 7 from being excessively deformed. However, according to such a conventional bearing structure, the grease in the bearing chamber 6 leaks out of the bearing chamber 6 due to the temperature rise in the bearing chamber 6 and the accompanying expansion of grease or air in the bearing chamber 6. There is a disadvantage that it will. Normally, the ship repeatedly travels and stops, thereby increasing and decreasing the temperature of the bearing chamber 6 (therefore, expansion and contraction of grease or air in the bearing chamber 6). Air enters the chamber 6, and when the temperature rises, the air expands again and grease is applied to the bearing chamber 6.
Since the grease is pushed out, there is a possibility that the amount of grease in the bearing chamber 6 may decrease due to repeated running and stopping of the ship. On the other hand, in such a bearing structure for a marine drive shaft, the inner diameter of the inner race 5a of the bearing member 5 is adjusted so that the drive shaft 1 (sleeve 1 'in the drawing, the same applies hereinafter) can be inserted into and removed from the bearing member 5. In contrast, the outer diameter of the drive shaft 1 is very small. Then, a reaction force from the impeller acts on the drive shaft 1 in the ship, and this reaction force acts in a state where the thrust force, the torsional force, and the bending force are combined in a complicated manner, and in consideration of assemblability. Since the clearance between the drive shaft and the inner race cannot be extremely reduced, the drive shaft 1 and the inner race 5a do not rotate together, and the outer peripheral surface 1a of the drive shaft 1 and the inner peripheral surface of the inner race 5a are in sliding contact. It is also possible. Under such circumstances, if the amount of grease in the bearing chamber 6 is reduced as described above, the outer peripheral surface 1a of the drive shaft 1 and / or the inner peripheral surface of the inner race 5a gradually become worn. Points had to be considered. For this reason, in the conventional bearing structure, it is necessary to periodically remove the drive shaft 1 from the bearing body 4 and fill the bearing chamber 6 with grease, depending on the running condition of the ship, and maintenance is troublesome. There was a problem. An object of the present invention is to provide a bearing structure for a marine drive shaft which can solve the above-mentioned problems and can reduce the frequency of maintenance as described above. According to a first aspect of the present invention, there is provided a marine drive shaft bearing structure in which a drive shaft for driving an impeller is rotatable with respect to a hull via a bearing member. In what we support,
A grease reservoir formed of a ring-shaped groove is provided on a surface of the drive shaft facing the bearing member. According to a first aspect of the present invention, there is provided a bearing structure for a marine drive shaft, which rotatably supports a drive shaft for driving an impeller with respect to a hull via a bearing member. Since the grease reservoir formed of the ring-shaped concave groove is provided on the surface facing the member, according to the bearing structure of the marine drive shaft, the grease in the grease reservoir causes the drive shaft and the bearing member to move between the drive shaft and the bearing member. Lubricity is ensured, and the outer peripheral surface of the drive shaft and / or the inner peripheral surface of the bearing member are less likely to be worn. Therefore,
Even if maintenance is performed, the frequency can be reduced. Therefore, in the case where the bearing chamber as described above is provided, even if the amount of grease in the bearing chamber is reduced, the grease in the grease reservoir allows lubrication between the drive shaft and the bearing member. Is secured, and the outer peripheral surface of the drive shaft and / or the inner peripheral surface of the bearing member are hardly worn, so that even if maintenance is performed, the frequency of maintenance can be reduced. Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a partially cut-away schematic side view showing an example of a personal watercraft using one embodiment of a bearing structure for a marine drive shaft according to the present invention.
FIG. As shown in these drawings (mainly FIG. 1), this personal watercraft 10 is a saddle-ride type small boat,
An occupant can sit on a seat 12 on the hull 11 and operate by holding a steering handle 13 with a throttle lever. The hull 11 has a floating structure in which a hull 14 and a deck 15 are joined to form a space 16 therein. In the space 16, an engine 20 is mounted on the hull 14, and a jet pump (jet propulsion pump) 30 as a propulsion unit driven by the engine 20 is provided at a rear portion of the hull 14. The jet pump 30 (see FIG. 3) has a jet port 3 opening at the rear end of the hull from an intake port 17 opening at the bottom of the hull.
1c2 and an impeller 32 disposed in the flow path 18 leading to the deflector 38, and a driving shaft (drive shaft) 22 of the impeller 32 is
1 (see FIGS. 1 and 4) via a coupler 23 (a driving coupler 23a and a driven coupler 23b). Therefore, the coupler 20
When the impeller 32 is driven to rotate via the shaft 3 and the shaft 22, the water taken in from the water intake 17 is ejected from the jet 3
The hull 11 is propelled from 1c2 through the deflector 38, thereby propelling the hull 11. The driving speed of the engine 20, that is, the propulsive force of the jet pump 30, is operated by turning the throttle lever 13a (see FIG. 2) of the operation handle 13. Deflector 38
Is linked to the operation handle 13 by an operation wire (not shown), and is turned by the operation of the handle 13, whereby the course of the hull 11 can be changed. FIG.
In the figure, 19 is a towing hook used for towing a tow target (rubber boat or the like), and is fixed to the rear part of the hull 11. FIG. 3 is a sectional view mainly showing a bearing structure of the jet pump 30 and the shaft 22, FIG. 4 is a partially enlarged view of FIG. 3, and FIG. 5 is a partially enlarged view of FIG. As shown in FIG. 3, the jet pump 30 includes a duct 31 that forms a flow path 18 that communicates with an intake port 17 provided at the bottom of the hull 11, an impeller 32 disposed in the duct 31, and a duct 31. Bearing portion 33 of the impeller provided therein, and a cap 34 for closing the rear end of the bearing portion 33
And The jet pump 30 is detachably attached to the hull 14 by fixing a flange portion 31d formed at a front portion of the duct 31 to the hull 14 with a bolt (not shown). [0011] The duct 31 includes an impeller accommodating portion 31a,
It has a bearing accommodation part 31b and a nozzle part 31c, and the impeller accommodation part 31a and the bearing accommodation part 31b are formed integrally. The stationary blade 31 is provided in the bearing accommodation portion 31b.
The bearing part 33 is integrally formed via b1. The impeller 32 has a front portion of a boss 32a engaged with a spline 22b formed at the rear end of the drive shaft 22, and rotates together with the drive shaft 22. The shaft 22 has a distal end 22 a connected to an output shaft 21 of an engine 20 mounted on the hull 11 via a coupler 23 (see FIG. 4). On the other hand, the bearing portion 33 has a rear portion 3 of the boss portion 32a of the impeller 32.
A support shaft 35 that supports 2b is rotatably supported via a ball bearing 33a. A male screw 35a is formed at the tip of the support shaft 35, and the male screw 35a is screwed with a female screw formed on the boss rear portion 32b of the impeller 32, so that the impeller 32 and the support shaft 35 are formed. And are combined. Therefore, impeller 32
The front portion of the boss portion 32a is connected to the shaft 22 and the rear portion 32b of the boss portion is connected to the support shaft 35, and rotates together with the shaft 22 and the support shaft 35. At the front of the cap 34, the bearing 3
3 is formed with an insertion portion (tubular portion) 34b to the rear portion, and three insertion holes 34c (only one is shown) of the screw 36 (see FIG. 3) are formed. Cylindrical insertion portion 34b
Has an O-ring (not shown) mounting groove formed therein. Therefore, the cap 34 is fitted with an O-ring on the insertion portion 34b, inserted (press-fitted) into the rear portion of the bearing portion 33 as shown in FIG. You. On the contact surface of the cap 34 with the bearing portion 33, a partial notch 34d is formed. At the time of maintenance, the screw 36 is removed, and the tip of a tool (for example, a screwdriver) is inserted into the notch 34d. The cap 34 can be easily removed. A stationary blade 31 facing the cap 34 is provided on a portion of the inner peripheral surface of the nozzle portion 31 c facing the cap 34.
c1 is formed. A bilge pipe 37 for discharging bilge water at the bottom of the ship is inserted into the nozzle portion 31c. The bilge pipe 37 is connected to a bilge pipe 60 in the hull via flow paths 31 e and 31 f provided above the duct 31 and a joint pipe 31 g. The joint pipe 31g on the jet pump 30 side and the bilge pipe 60 are detachably connected by press fitting.
When removing the jet pump 30 from the hull 14, the bilge pipe 60 can be removed from the joint pipe 31g. The above-described deflector 38 is rotatably attached to a rear portion of the nozzle portion 31c. As shown in FIGS. 3 and 4, the hull 14
A bearing cover 43 is fixed, and a bearing body 50 with a rubber damper as a bearing body is attached to the bearing cover 43.
Has been fixed. The bearing body 50 is for rotatably supporting the intermediate portion of the shaft 22 on the hull 11. As shown in FIGS. 4 and 5, the bearing body 50 includes a rubber body 51 forming a rubber damper portion, and a plurality of bearing members (shown in FIG. 4) housed in the body 51 and rotatably supporting the shaft 22. Is two ball bearings)
52, 52, a seal member 53 incorporated on the engine side of the bearing 52, and a seal member 54 incorporated on the jet pump 30 side (the flow path 18 side) of the bearing 52 (FIG. 5 in this embodiment). , Two seal members 54a and 54b).
The main body 51 has a tubular portion 51a and a flange portion 51b integral with the tubular portion 51a, and the bearing 52 and the sealing members 53 and 54 are incorporated in the tubular portion 51a. As shown in FIG. 5, the seal members disposed on both sides of the bearing 52, that is, the seal member 53 disposed on the engine side and the seal member 54a disposed on the jet pump 30 side are formed on the outer periphery of the drive shaft 22. Bearing member (bearing) by contacting surface 22e
A bearing chamber 51f accommodating 52 is defined. That is, the bearing chamber 51f is provided with the inner peripheral surface 51a1 of the cylindrical portion 51a.
, The outer peripheral surface 22e of the shaft 22, the inner surface 53a of the seal member 53, and the inner surface 54a1 of the seal member 54a. This space (51
f) also forms a grease filling chamber, as described below. The bearing 52 is mounted on the drive shaft 22.
An inner race 52a abutting on the outer peripheral surface 22e of the inner race 52a, and an outer race 52 disposed outside the inner race 52a via a rotating body (a ball is shown) 52b.
and a grease reservoir 22f formed of a ring-shaped groove is provided on the surface of the drive shaft 22 facing the bearing member (in this case, the surface facing the inner race 52a). The corners 22g of the ring-shaped concave grooves forming the grease reservoir 22f are chamfered to facilitate insertion and removal of the shaft 22 from the bearing 52. In this embodiment, two bearings 52 are provided as shown in FIG.
f is provided so as to straddle both bearings 52 between the two bearings 52, but when there is only one bearing 52, as shown in FIG. Inner peripheral surface 52 of race 52a
e may be provided so as to be totally closed,
As shown in FIG. 5B, the inner race 52a may be provided so as to be partially covered by the inner peripheral surface 52e. As shown in FIG. 4, the cylindrical portion 51a of the bearing body 50 forms a rubber cylindrical portion 51g extending toward a hull-side cylindrical portion 46a described later. A metal reinforcing member 51c is provided on the flange portion 51b of the bearing body 50.
Are provided integrally. On the other hand, the front wall 43a of the bearing cover 43 is provided with a hole 43b for inserting the cylindrical portion 51a of the bearing body 50, and a metal ring-shaped base 44 is provided around the hole 43b with an adhesive. Tightly adhered. A bolt 44b is integrally implanted in the base 44. The bearing body 50 has a rubber cylindrical portion 5.
1g is inserted through the hole 43b of the bearing cover 43, and the bolt 44b is inserted through the reinforcing member 51c of the flange portion 51b.
5 is screwed from the inside of the hull to tighten the flange portion 51b (therefore, the reinforcing member 51c),
It is fixed to the bearing cover 43 (therefore, the hull 11). The rear end of the rubber cylindrical portion 51g is connected to the hull 14 by a ring-shaped clamp 47 to the cylindrical portion 46a of the joint rubber 46 mounted tightly with an adhesive from the flow channel 18 side with an adhesive. I have. As shown in FIGS. 4 and 5, the bearing 5
A grease supply hole 51d communicating with the bearing chamber (grease filling chamber) 51f is formed in the 0 cylindrical portion 51a. A grease supply hose 56 is connected to the grease supply hole 51d via a connection pipe 55, and a grease nipple 56a is provided at the tip thereof. The grease nipple 56a is a mounting bracket 56b,
5, near the opening 15 a when the sheet 12 is opened, it is fixed together with the aforementioned towing hook 19 (see FIG. 1). Therefore, by opening the sheet 12, grease can be easily supplied from the grease nipple 56a to the bearing chamber (grease filling chamber) 51f via the grease supply hose 56. The grease filled in the bearing chamber 51f is supplied to the bearing 52
Inner and / or bearing 52 and drive shaft 2
The grease reservoir 22f is also filled into the grease reservoir 22f through a slight gap between the grease reservoir 22f and the outer peripheral surface 22e. According to the bearing structure of the marine drive shaft as described above, the following operational effects can be obtained. (A) A grease formed of a ring-shaped groove on a surface 22e of the drive shaft 22 facing the bearing member 52 in a case where the drive shaft 22 for driving the impeller 32 is rotatably supported on the hull 11 via a bearing member 52. Since the reservoir 22f is provided, according to the marine drive shaft bearing structure, the grease in the grease reservoir 22f causes the drive shaft 2
Lubricity between the shaft member 2 and the bearing member 52 is ensured, and the outer peripheral surface 22e of the drive shaft 22 and / or the inner peripheral surface 52e of the bearing member 52 are less likely to be worn. Therefore,
Even if maintenance is performed, the frequency can be reduced. Therefore, in the case where the bearing chamber 51f is provided as in this embodiment, even if the amount of grease in the bearing chamber 51f is reduced, the grease in the grease reservoir 22f allows the drive shaft 22 and the bearing to be fixed. Lubricity between the member 52 and the outer peripheral surface 22e of the drive shaft 22 is ensured.
In addition, since the inner peripheral surface 52e of the bearing member 52 is less likely to be worn, even if maintenance is performed, the frequency of the maintenance can be reduced. (B) The bearing body 50 has a bearing member 52 rotatably supporting the drive shaft 22, a bearing chamber 51f for accommodating the bearing member 52, and an outer peripheral surface 22e of the drive shaft 22 disposed on both sides of the bearing member 52. Seal members 53 and 54a that partition the bearing chamber 51f by contact of
And a grease supply hole 51 with respect to the bearing chamber 51f.
d and the grease supply hose 56 are in communication with each other, so that the temperature in the bearing chamber 51f rises and the bearing chamber 51f
Even if the grease or air in the inside expands, the expanded grease or air escapes to the grease supply hole 51d and the grease supply hose 56, so that even if the internal pressure in the bearing chamber 51f does not increase or increases. The rise is significantly suppressed. Therefore,
Depending on the internal pressure in the bearing chamber 51f, the sealing members 53, 5
4a is basically not deformed, so that there is no gap between the seal members 53, 54a and the shaft outer peripheral surface 22e. Therefore, the grease or air in the bearing chamber 51f allows the seal members 53, 54a and the shaft outer periphery to be removed. It is difficult to leak out of the room from the gap between the surface 22e. The grease or air that escapes into the grease supply hole 51d and the grease supply hose 56 due to the temperature rise in the bearing chamber 51f is stopped when the running of the boat 10 is stopped and the temperature in the bearing chamber 51f decreases. Will return to.
Therefore, according to the bearing structure of the marine drive shaft, the seal members 53 and 54a are prevented from being excessively deformed due to an increase in the internal pressure of the bearing chamber 51f, and at the same time, running and stopping of the boat are repeated to reduce the bearing chamber temperature. Even if ascending and descending (accordingly, the grease in the bearing chamber 51f or expansion and contraction of air) are repeated, the grease in the bearing chamber 51f does not basically decrease, and even if it does decrease, the degree of the decrease is reduced. It will be extremely suppressed. As a result, according to this bearing structure, in combination with the operation and effect (a) described above, the maintenance for removing the shaft 22 as required in the prior art is basically unnecessary, and the maintenance is temporarily performed. Is performed, the effect is obtained that the frequency is extremely low. (C) A grease supply hose 56 is connected to the bearing body 50, and grease can be injected by the grease supply hose 56. Therefore, the bearing chamber 51 f and the grease reservoir 22 f without removing the drive shaft 22 from the bearing body 50. Can be filled with grease. Therefore, even if maintenance (grease filling) is required, the maintenance can be easily performed. Although the embodiments and examples of the present invention have been described above, the present invention is not limited to the above-described embodiments or examples, and can be appropriately modified within the scope of the present invention. It is. [0022]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partially cut-away schematic side view showing an example of a personal watercraft using one embodiment of a bearing structure for a marine drive shaft according to the present invention. FIG. 2 is a schematic plan view of the same. FIG. 3 mainly shows a jet pump 30 and a shaft 2
Sectional drawing which shows 2 bearing structures. FIG. 4 is a partially enlarged view of FIG. 3; FIG. 5 is a partially enlarged view of FIG. 4; FIGS. 6A and 6B are diagrams showing a modification of the bearing structure of the marine drive shaft according to the present invention. FIG. 7 is an explanatory diagram of a conventional technique. [Description of Signs] 11 Hull 22 Drive shaft 22e Outer peripheral surface (opposed surface) 32 Impeller 52 Ball bearing (bearing member) 22f Grease pool

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) F16N 11/00 F16N 11/00

Claims (1)

Claims 1. A drive shaft for driving an impeller for rotatably supporting a hull via a bearing member, wherein a ring-shaped groove is formed on a surface of the drive shaft facing the bearing member. A bearing structure for a marine drive shaft, comprising a grease reservoir made of: