JP2001303920A - Spline lubrication structure for outboard motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To constantly lubricate a space of a spline coupling of a crank shaft of an engine with a drive shaft of a screw by utilizing an existing lubricating oil passage feeding the lubricating oil to components to be lubricated of the engine. SOLUTION: A part of the lubricating oil in the lubricating oil passage 1 formed in the engine 2 of an outboard motor 1 is press-fed to the space of the spline coupling of the crank shaft 3 with the drive shaft 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a spline lubrication structure for an outboard motor.

[0002]

2. Description of the Related Art As shown in FIG. 4, in an outboard motor 1 for a small boat, an upper end of a drive shaft 5 for driving a screw 4 is connected to a lower end of a crankshaft 3 of an engine 2 installed vertically. Have been.

The engine 2 has a lower mating surface fixed to an upper mating surface of the guide exhaust 6. During maintenance of the engine 2, the engine 2 is removed from the male spline of the drive shaft 5 while removing the engine 2 from the guide exhaust 6. The female spline of the shaft 3 is extracted.

On the other hand, as shown in FIG. 5, lubrication parts (crankshaft 3, camshaft 8, rocker shaft) are provided to engine 2 of outboard motor 1 as described above by oil pump 7 driven by engine 2. 9) and an oil pan 1
A lubricating oil passage 11 for supplying lubricating oil a (see arrow) from 0 is formed.

[0005]

Grease is filled in the gap between the spline connection between the crankshaft 3 and the drive shaft 5 of the engine 2 described above.
In the case where the grease has been lost by the time of maintenance, if the spline connection portion is seized due to wear, it is difficult to remove the female spline of the crankshaft 3 from the male spline of the drive shaft 5 when the engine 2 is maintained. was there.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems. The present invention utilizes an existing lubricating oil passage for supplying lubricating oil to lubricating parts of an engine, and uses an engine crankshaft and a screw drive shaft. It is an object of the present invention to provide a spline lubrication structure for an outboard motor, which can always lubricate the gap between the spline and the spline.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides an outboard motor in which a drive shaft for driving a screw is connected to a crankshaft of the engine by an spline. A lubricating oil passage for supplying lubricating oil to the lubricating part, and a part of the lubricating oil is supplied by pressure to a gap portion of the spline connection; Is provided.

According to the present invention, a part of the lubricating oil in the lubricating oil passage for supplying the lubricating oil from the oil pump to the lubricating parts of the engine is provided in the gap between the spline connection between the crankshaft of the engine and the drive shaft of the screw. Since the pressure is supplied by pumping, the gaps in the spline connection are always lubricated with lubricating oil, so there is no danger of the spline connection becoming worn and seized. The operation of extracting the female spline of the shaft can be performed without any trouble. In addition, the work of extracting the female spline of the crankshaft from the male spline of the drive shaft while removing the engine from the guide exhaust is no longer necessary only for the work of filling grease in the gap part of the spline connection as in the past. In addition, maintenance-free operation can be achieved.

The lower surface of the engine is fixed to the upper surface of the guide exhaust, and the male spline of the drive shaft projecting upward from the upper surface of the guide exhaust is connected to the crankshaft of the engine. An oil reservoir is formed on the upper surface of the guide exhaust around the base of the male spline, and a part of the lubricating oil supplied to the oil reservoir is formed in a gap portion of the spline coupling. The lubricating oil in the oil reservoir is smoothly supplied to the gap of the spline connection by capillary action. Further, the worn metal powder that has peeled and dropped from the spline connection portion is collected in the oil pool.

According to a third aspect of the present invention, a lower mating surface of the engine is fixed to an upper mating surface of the guide exhaust, and a male spline of the drive shaft protruding upward from the upper mating surface of the guide exhaust is connected to the crankshaft of the engine. While the female splines are combined, an oil reservoir is formed on the upper surface of the guide exhaust around the base of the male spline, and a through hole is formed in the crankshaft on which the female spline is formed in a direction perpendicular to the axis. If a part of the lubricating oil supplied to the oil distribution groove on the inner periphery of the bearing that supports the crankshaft is configured to be pressure-fed and supplied from the through hole to the gap portion of the spline connection, the oil on the inner periphery of the bearing Lubricating oil supplied to the distribution groove flows from the through hole to the gap of the spline connection by capillary action It comes to be pumped supplied smoothly.

According to a fourth aspect of the present invention, in the oil reservoir,
When the oil return passage for returning the surplus lubricating oil to the lubricating oil passage is formed, the surplus lubricating oil and the wear metal powder collected in the oil reservoir are quickly discharged from the oil reservoir.

According to a fifth aspect of the present invention, the bottom of the oil reservoir is formed of an oil seal that seals between the outer periphery of the drive shaft and the drive shaft through hole of the guide exhaust. Can be shared with an existing oil seal.

According to a sixth aspect of the present invention, an air vent hole is formed in the upper bottom portion of the female spline.
The air in the spline connection portion is released, and the lubricating oil is more smoothly supplied under pressure to the gap portion.

[0014]

Embodiments of the present invention will be described below in detail with reference to the drawings. Note that the same components and operations as those of the prior art are denoted by the same reference numerals, and detailed description thereof will be omitted.

FIGS. 1 and 2 show a first embodiment.
Is an enlarged sectional view of a spline connection part, and FIG.
FIG. 3 is a plan view of the upper mating surface of the guide exhaust 6 corresponding to the line A.

The engine 2 is, for example, a four-stroke engine (a two-stroke engine is also possible). The lower mating surface 2a of the engine 2 is brought into contact with the upper mating surface 6a of the guide exhaust 6 via a gasket, and the crank is cranked. The shaft 3 and the like are arranged vertically so as to be vertical. The engine 2 is detachably fixed to the guide exhaust 6 with bolts or the like so that the engine 2 can be removed from the guide exhaust 6 during maintenance.

The lower end 3a of the crankshaft 3 of the engine 2 is rotatably supported by a metal bearing 16 attached to a through hole 15a of the crankcase 15 of the engine 2, and the lower end 3b of the lower end 3a. Is set so as not to protrude below the lower mating surface 2a of the engine 2. A lower end portion 3a is provided below the through hole 15a.
An oil seal 17 is provided for sealing between the oil seal and the outer periphery of the oil seal.

A female spline 3c extending upward from a lower end surface 3b is formed at a lower end 3a of the crankshaft 3, and a small-diameter air vent 3d is formed at an upper bottom portion of the female spline 3c. I have.

An upper end 5a of the drive shaft 5 projecting upward from the upper mating surface 6a of the guide exhaust 6 has a male spline 5c spline-coupled from below to the female spline 3c of the lower end 3a of the crankshaft 3.
Are formed.

The male spline 5 of the drive shaft 5
c, a shallow recessed oil reservoir 6b having substantially the same diameter as the through hole 15a of the crankcase 15 is formed on the upper mating surface 6a of the guide exhaust 6 around the base of the guide exhaust 6, and the grooves of the male and female splines 3c, 5c It extends into the pool 6b.

The bottom of the oil reservoir 6b is formed by an oil seal 18 for sealing between the outer periphery of the drive shaft 5 and the drive shaft through hole 6c of the guide exhaust 6. The oil seal 18 serves to seal seawater and the like on the guide exhaust 6 side so as not to enter the engine 2 side.
The bottom of b is also used by the existing oil seal 18.

A part b of the lubricating oil a in the lubricating oil passage 11 for supplying lubricating oil from the oil pump 7 to the lubricating parts of the engine 2 is stored in the oil sump 6b on the inner periphery of the through hole 15a of the crankcase 15. An oil supply passage 15b is formed for supplying oil, and an excess amount of lubricating oil b is supplied to the oil pan 10 via a lubricating oil passage 11 on the inner periphery of the oil reservoir 6b of the guide exhaust 6.
An oil return passage 6d (see FIG. 2) is formed to return the oil pressure to the pressure.

If the spline lubricating structure of the first embodiment is constructed as described above, the lubricating oil passage 1 for supplying lubricating oil from the oil pump 7 to the lubricating parts of the engine 2 will be described.
When a part b of the lubricating oil a is supplied from the oil supply passage 15b to the oil reservoir 6b by pressure, the lubricating oil b supplied to the oil reservoir 6b is supplied to the crankshaft by capillary action as shown by an arrow. The female spline 3c of the drive shaft 3 and the male spline 5c of the drive shaft 5 are smoothly fed under pressure from the lower side to the upper side. In this case, since the air in the spline connection portion is released along with the supply of the lubricating oil b through the air vent hole 3d in the upper bottom portion of the female spline 3c, the lubricating oil b is smoothly supplied to the gap by the pressure supply. .

As a result, the gap between the spline joints of the male and female splines 3c and 5c is always lubricated with the lubricating oil b, so that there is no danger of the spline joints being worn and seized. The operation of extracting the female spline 3c of the crankshaft 3 from the male spline 5c of the shaft 5 can be performed without any trouble.

In addition, as in the prior art, the engine 2 is removed from the guide exhaust 6 while the engine 2 is removed from the male spline 5c of the drive shaft 5 only for the operation of filling grease into the gap portion of the spline connection.
The operation of extracting the female spline 3c is unnecessary, and maintenance-free operation can be achieved.

Further, the surplus lubricating oil b supplied to the oil sump 6b is returned to the lubricating oil passage of the engine 2 from the oil return passage 6d (see FIG. 2). The worn metal powder that has fallen and is collected in the oil pool 6b is quickly discharged from the oil pool 6b. Further, since the grooves of the male and female splines 3c and 5c extend into the oil reservoir 6, the wear metal powder descends along the grooves and is easily introduced into the oil reservoir 6b.

FIG. 3 shows a second embodiment. FIG. 3 (a) is an enlarged sectional view of a spline connection portion, and FIG. 3 (b) is a sectional perspective view of a main part of the metal bearing 16.

The metal bearing 16 has an oil distribution groove 16a formed on the inner periphery of the bearing. The oil supply groove 1a is formed in the oil distribution groove 16a.
6b, a part d of the lubricating oil a in the lubricating oil passage 11 for supplying the lubricating oil from the oil pump 7 to the lubricating parts of the engine 2 is supplied from the oil supply hole 16b to the oil distribution groove 16a. The lubrication is provided between the inner circumference of the bearing and the outer circumference of the lower end 3a of the crankshaft 3.

The difference from the first embodiment is that the oil supply passage 15b is not formed in the inner periphery of the through hole 15a of the crankcase 15, but the lower end of the crankshaft 3 having the female spline 3c is formed. 3b, a through hole 3e in the direction perpendicular to the axis is formed so as to match the oil distribution groove 16a of the metal bearing 16.

If the spline lubricating structure of the second embodiment is constructed as described above, the lubricating oil passage 1 for supplying lubricating oil from the oil pump 7 to the lubricating parts of the engine 2 will be described.
A portion d of the first lubricating oil a is supplied from the oil supply hole 16b to the oil distribution groove 16a, and is lubricated between the inner periphery of the bearing and the outer periphery of the lower end 3a of the crankshaft 3, while the oil is distributed. Further a part e of the lubricating oil d supplied to the groove 16a is pressure-fed to the through hole 3e,
Due to the capillarity, upward and downward branching occurs in the gap between the spline connection between the female spline 3c of the crankshaft 3 and the male spline 5c of the drive shaft 5, so that the pressure can be smoothly supplied. Thereby, the same operation and effect as in the first embodiment can be obtained.

[0031]

As is apparent from the above description, according to the present invention, a part of the lubricating oil in the lubricating oil passage for supplying the lubricating oil from the oil pump to the lubricating parts of the engine is removed from the crankshaft and the screw of the engine. Since the pressure is supplied to the gap between the spline connection with the drive shaft, the gap between the spline connection is always lubricated with lubricating oil. At the time of maintenance, the work of extracting the female spline of the crankshaft from the male spline of the drive shaft can be performed without any trouble. In addition, the work of removing the female spline of the crankshaft from the male spline of the drive shaft while removing the engine from the guide exhaust is no longer necessary only for the work of filling grease in the gap part of the spline connection as in the past. Thus, maintenance-free operation can be achieved.

If a part of the lubricating oil supplied to the oil reservoir formed in the guide exhaust is supplied to the gap portion of the spline connection by pressure, the lubricating oil in the oil reservoir becomes a capillary phenomenon. Thereby, the pressure is smoothly supplied to the gap portion of the spline connection. Further, the worn metal powder that has peeled and dropped from the spline connection portion is collected in the oil pool.

According to a third aspect of the present invention, a part of the lubricating oil supplied to the oil distribution groove on the inner periphery of the bearing that supports the crankshaft is pressure-fed and supplied from the through hole of the crankshaft to the gap portion of the spline connection. With this configuration, the lubricating oil supplied to the oil distribution groove on the inner circumference of the bearing is smoothly supplied from the through hole to the gap portion of the spline connection by capillary action.

According to a fourth aspect of the present invention, when an oil return passage for returning excess lubricating oil to the lubricating oil passage is formed in the oil reservoir, the surplus lubricating oil and wear metal powder collected in the oil reservoir are quickly removed from the oil reservoir. Will be discharged.

When the bottom of the oil reservoir is formed by an oil seal, the existing oil seal can also serve as the bottom of the oil reservoir.

When an air vent hole is formed in the upper bottom portion of the female spline as described in claim 6, the air in the spline joint portion is released, and the lubricating oil is smoothly supplied under pressure to the gap portion.

[Brief description of the drawings]

FIG. 1 is an enlarged sectional view of a spline connection portion according to a first embodiment of the present invention.

FIG. 2 is a plan view of the upper surface of the guide exhaust corresponding to the line AA in FIG. 1;

FIG. 3A is an enlarged cross-sectional view of a spline connection portion according to a second embodiment of the present invention, and FIG. 3B is a cross-sectional perspective view of a main part of a metal bearing.

FIG. 4 is a schematic side view of the outboard motor.

FIG. 5 is an oil lubrication path diagram of the engine.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Outboard motor 2 Engine 2a Lower mating surface 3 Crankshaft 3c Female spline 3d Air vent hole 3e Through hole 5 Drive shaft 5c Male spline 6 Guide exhaust 6a Upper mating surface 6b Oil reservoir 6d Oil return passage 11 Lubricating oil passage 16 Metal bearing 16a Oil distribution groove 16b Oil supply hole 18 Oil seal

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (Reference) F01M 1/06 B63H 21/26 K

Claims (6)

[Claims] 1. An outboard motor in which a drive shaft driving a screw is spline-coupled to a crankshaft of an engine, wherein the engine has a lubricating oil passage for supplying lubricating oil from an oil pump to lubricating components. A spline lubricating structure for an outboard motor, wherein a part of the lubricating oil is supplied under pressure to the gap portion of the spline connection. 2. A female spline of a crankshaft of the engine is coupled to a male spline of a drive shaft protruding upward from an upper mating surface of the guide exhaust, wherein a lower mating surface of the engine is fixed to an upper mating surface of the guide exhaust. On the other hand, an oil sump is formed on the upper surface of the guide exhaust around the base of the male spline, and a part of the lubricating oil supplied to the oil sump is supplied under pressure to a gap portion of the spline connection. 3. The spline lubrication structure for an outboard motor according to claim 1, wherein: 3. A female spline of a crankshaft of the engine is coupled to a male spline of a drive shaft protruding upward from an upper mating surface of the guide exhaust, wherein a lower mating surface of the engine is fixed to an upper mating surface of the guide exhaust. On the other hand, an oil reservoir is formed on the upper surface of the guide exhaust around the base of the male spline, and a through-hole is formed in the crankshaft on which the female spline is formed in a direction perpendicular to the axis. 2. A spline lubrication structure for an outboard motor according to claim 1, wherein a part of the lubricating oil supplied to an oil distribution groove on the inner periphery of the bearing for supporting the spline is supplied by pressure from the through hole to a gap portion of the spline connection. . 4. The spline lubrication structure for an outboard motor according to claim 2, wherein an oil return passage for returning excess lubricating oil to the lubricating oil passage is formed in the oil reservoir. 5. The oil reservoir according to claim 2, wherein the bottom of the oil reservoir is formed by an oil seal that seals between an outer periphery of the drive shaft and a drive shaft through hole of the guide exhaust. Outboard motor spline lubrication structure. 6. The spline lubrication structure for an outboard motor according to claim 2, wherein an air vent hole is formed in an upper bottom portion of said female spline.