JP2001098918A - Engine crankcasing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an engine with a crank casing which can reduce the possibility of leakage of lubrication oil from a connection part of an oil pan, in comparison with a conventional crank casing. SOLUTION: In an engine crank casing in which a gasket 33 is held between an oil pan attaching surface 40 formed in the lower part of a crank casing 20, and an upper end surface 9a of the oil pan before the oil pan is attached, ribs 29 are provided at four corners of a lower opening 26 in the crank casing. With this arrangement, the ribs 29 serves as brims so that the lubrication oil falls down from the tip ends of the ribs 29, and accordingly, the lubrication oil is prevented from staying on the gasket at the corners for a long time, so as to prevent the lubrication oil from making contact with the gasket 33 for a long time, thereby it is possible to prevent oil leakage at the four corners where the ribs are formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a crankcase of an engine, and more particularly to a crankcase of an engine capable of preventing leakage of lubricating oil from a connection between a crankcase and an oil pan.

[0002]

2. Description of the Related Art Conventionally, an oil pan has been attached to a lower portion of a crankcase of an engine. Normally, a gasket is sandwiched between the connecting portions of the crankcase and the oil pan to maintain airtightness and to prevent lubricating oil from leaking from the connecting portions.

FIG. 4 is a side view showing a main part of a vertical water-cooled diesel engine cut away. FIG. 5 is a longitudinal sectional view of a cylinder block of the engine, and FIG. 6 is a bottom view of a crack case of the engine.

In a multi-cylinder engine, as shown in FIGS. 4 and 5, a plurality of cylinders 2, a crankcase 20, and a plurality of bearing walls 21 for supporting a crankshaft 8 are integrally formed.
A tunnel-type support hole 22 is formed in each of the bearing walls 21, and a split bearing box 11 is assembled in advance to each of the intermediate journals 8 a of the crankshaft 8. The crankshaft 8 is attached to the rear of the crankcase 20 (on the flywheel 7 side). More bearing wall 2
1 and inserted into the crankcase 20 through the inside of the tunnel-shaped support hole 22, and the bearing box 11 is fitted and fixed in each of the support holes 22. To support the intermediate journal 8a of the crankshaft 8.

Reference numeral E in FIG. 4 indicates the entire diesel engine, 1 is a cylinder block integrally formed with a crankcase, 3 is a cylinder head, 4 is a gear case, 5 is a fan drive pulley, and 6 is a cooling unit. A fan, 9 is an oil pan, and 15 is a piston. As shown in FIG.
An oil pan mounting surface 40 is formed on the lower end surface of the crankcase 20, a bolt hole 41 is formed in the oil pan mounting surface 40, and the gasket 33 is sandwiched between the oil pan upper surface 9a and the oil pan upper surface 9a as shown in FIG. The oil pan 9 is configured to be attached by a tightening bolt.

[0006]

However, the structure of the conventional crankcase of the engine has the following problems. As shown in FIG. 6, when the rectangular openings 27 are provided corresponding to the respective cylinders of the engine, the lubricating oil is likely to be accumulated in the corners 42 of the square openings 27, and the gasket at the corners 42 is formed. I have a painful problem.

When the engine is operated normally,
Although lubricating oil does not leak from the connection between the crankcase and the oil pan, there is a danger that the lubricating oil will leak from the connection between the crankcase and the oil pan if the gasket is severely consumed due to any factor. In addition, it is desired that the lubricating oil is configured not to leak from the connecting portion of the oil pan as much as possible in all areas of the lower opening 26 of the crankcase, not only in the four corners where lubricating oil is likely to stay.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide an engine crankcase which can solve the above problems. An example of a specific purpose is as follows. (a) To provide an engine crankcase that can reduce the risk of lubricating oil leaking from an oil pan connection as compared to a conventional crankcase. It should be noted that the problems of the invention other than those described above and the means for solving the problems will be described in detail in the description in the following specification.

[0009]

The present invention will be described below with reference to, for example, FIGS. 1 to 3 showing an embodiment of the present invention. The first invention is shown in FIG.
As shown in FIG. 2, an oil pan mounting surface 40 is formed at a lower portion of the crankcase 20, and the oil pan mounting surface 4 is formed.
In the crankcase of the engine configured to mount the oil pan 9 with the airtight holding means 36 interposed between the oil pan 9 and the upper end surface 9a of the oil pan, at least one corner 42 of the lower opening 26 of the crankcase is provided with the inside of the crankcase. A rib body 29 protruding to the side is provided.

In the second invention, a crankcase lower opening 26 is provided.
Characterized in that the ribs 29 are provided at the four corners. The third invention is characterized in that when the crankshaft 8, the balance weight 34, and the like rotate, the rib body 29 is provided on the side of the lower opening 26 corresponding to the inner wall of the crankcase where a large amount of lubricating oil scattered by the rotation is applied. And

The first to third inventions will be further described. In the first invention, the airtight holding means 3
As 6, a gasket 33 or the like is used. The crankcase lower opening 26 is an opening that opens toward the oil pan 9 formed at the lower part of the crankcase 20.

[0012]

According to the first aspect of the invention, by providing the rib at at least one corner of the lower opening of the crankcase, the rib serves as an eave, and the lubricating oil flows down from the tip of the eave. Lubricating oil stays in the airtight holding member at the corner, and the state in which the lubricating oil remains in contact with the airtight holding member for a long time can be eliminated, and oil leakage at the corner can be prevented. Further, by providing the rib body at at least one corner of the lower opening of the crankcase, it is possible to suppress the vibration that causes the noise of the crankcase.

According to the second aspect of the invention, by providing the ribs at the four corners of the lower opening of the crankcase, oil leakage can be suppressed at all corners where the ribs are provided. In addition, by providing the ribs at the four corners of the lower opening of the crankcase, vibrations that cause crankcase noise can be further reduced. According to the third aspect, the rib body is provided on the side of the lower opening corresponding to the inner wall of the crankcase where a large amount of scattered lubricating oil is applied, thereby preventing leakage of the lubricating oil corresponding to the inner wall of the crankcase where a large amount of lubricating oil flows down. can do.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a longitudinal sectional view of the crankcase according to the present embodiment. FIG. 2 is a bottom view of the crankcase. The configuration of the engine employing the crankcase according to this embodiment is basically the same as the engine shown in FIGS.

That is, as shown in FIG. 4, a plurality of cylinders 2, a plurality of bearing walls 21 for supporting the crankcase 20 and the crankshaft 8 are integrally formed, and a tunnel-type support hole is formed in each of the bearing walls 21. A tunnel-shaped bearing box 11 is mounted on each intermediate journal 8a of the crankshaft 8 in advance, and the crankshaft 8 is opened from the rear of the crankcase 20 (on the flywheel 7 side) to the bearing wall 21. The bearing box 11 is inserted into the support hole 22 and incorporated into the crankcase 20, and the bearing box 11 is fitted and fixed in each of the support holes 22, and the intermediate journal of the crankshaft 8 is inserted into the center bearing hole 12 of the bearing box 11. 8a.

The crankcase 20 according to this embodiment is also formed integrally with the cylinder block 1. As described above, the crankcase 20 is formed with the three bearing walls 21 for supporting the crankshaft 8, and as shown in FIG. Four lower openings 26 are formed. Each of the four lower openings 26 is a substantially square opening 2
7 and has a short side 28 in the transverse direction of the crankshaft 8 (engine longitudinal direction) and a long side 35 in a direction perpendicular to the transverse direction of the crankshaft 8 (engine width direction). I have.

An eave-shaped rib 29 is formed along two sides of the rectangular opening 27 parallel to the engine front-rear direction, that is, two short sides 28 shown in FIG. This rib body 29 has a short side 28
Are formed to have an edge surface 30 parallel to.

The operation of this embodiment will be briefly described. The lubricating oil 32 flowing along the inner wall surface of the crankcase 20 as shown in FIG.
1 (see FIG. 2), the oil lubricating oil 9 flows down to the oil pan 9, so that a large amount of the lubricating oil 32 does not come into direct contact with the gasket 33 sandwiched between the crankcase 20 and the oil pan 9 as in the related art. Exudation of lubricating oil can be prevented.

Further, when the balance weight 34 of the crankshaft 8 shown in FIG. 1 rotates, the side of the rectangular opening 27 (FIG. 2) corresponding to the inner wall of the crankcase to which the lubricating oil 32 scattered by the rotation rotates. In this case, the rib body 29 is provided mainly on the short side 28 of the rectangular opening 27), thereby effectively preventing the lubricating oil 32 scattered by the rotation of the crankshaft 8 from directly flowing down to the gasket 33. be able to.

The lower opening 26 of the crankcase 20
Crankcase 20 including at least one corner 42 of
By providing the rib body 29 protruding inward, there is an additional effect that vibration of the crankcase 20, which is one of the causes of generating engine noise, can be suppressed. In particular,
In the configuration shown in FIG. 2, since the ribs 29 are provided at all four corners of the rectangular opening 27, the vibration of the crankcase can be greatly suppressed.

[0021]

Second Embodiment FIG. 3 is a bottom view of a crankcase showing a second embodiment of the present invention. In the second embodiment,
A rib body 29 is provided at each of the four corners of the lower opening 26 of the crankcase 20.

It is preferable that the rib body 29 is formed at the corner formed by the short side 28 and the long side 35 of the rectangular opening 27 so as to cover the short side 28 and the long side 35, respectively. With this configuration, the presence of the ribs 29 formed at the four corners of the lower opening 26 of the crankcase 20 in which the lubricating oil easily accumulates can suppress the leakage of the lubricating oil from a gasket or the like at that portion.

The present invention is not limited to the above embodiment, and various design changes can be made without departing from the spirit of the present invention. Hereinafter, such an embodiment will be described. (1) In the above embodiment, a four-cylinder multi-cylinder engine has been described as an example, but a single-cylinder engine is also applicable.

(2) In the embodiment shown in FIG. 2, a configuration in which the ribs 29 are arranged on the short sides 28 of the rectangular openings 27 with emphasis 29 is exemplified, but not only the short sides 28 but also the squares in FIG. A configuration in which the rib body 29 is provided over the entire length of the long side 35 of the opening 27 is also possible.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a crankcase of an engine according to a first embodiment of the present invention.

FIG. 2 is a bottom view of the crankcase.

FIG. 3 is a bottom view of a crankcase according to a second embodiment of the present invention.

FIG. 4 is a side view showing a main part of the vertical water-cooled diesel engine cut away.

FIG. 5 is a longitudinal sectional view of a cylinder block of the engine shown in FIG. 4;

FIG. 6 is a bottom view of the crankcase shown in FIG.

[Explanation of symbols]

8 ... Crank shaft, 9 ... Oil pan, 9a ... Oil pan upper end face, 20 ... Crank case, 26 ... Lower opening, 29 ...
Rib body, 34: balance weight, 36: airtight holding means, 40: oil pan mounting surface, 42: corner.

Continued on the front page (72) Inventor Masao Okazaki 3-8 Chikushinmachi, Sakai-shi, Osaka F-term in Kubota Sakai Coastal Plant 3G015 AA07 BA00 BA07 CA06 DA01 DA10 EA04 EA11 3G024 AA46 BA05 BA23 DA18 DA21 FA02 FA07 FA08

Claims (3)

[Claims] An oil pan mounting surface (40) is formed at a lower portion of the crankcase (20), and the oil pan mounting surface (40) is formed.
Airtight holding means (36) between the oil pan upper surface (9a) and
In the crankcase of the engine configured to mount the oil pan (9) with the oil pan (9) interposed therebetween, at least one corner (42) of the lower opening (26) of the crankcase, a rib body (29) protruding inside the crankcase. A crankcase for an engine, comprising: 2. The engine crankcase according to claim 1, wherein said ribs (29) are provided at four corners of a crankcase lower opening (26). 3. The engine crankcase according to claim 1, wherein the crankshaft (8), the balance weight (34), and the like rotate.
An engine crankcase, wherein the rib body (29) is provided on a side of the lower opening (26) corresponding to an inner wall of the crankcase to which a large amount of lubricating oil scattered by the rotation is applied.