JP2003286816A - Internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an internal combustion engine in which the amount of consumption of lubricating oil can be reduced by improving the spreadability of the oil. <P>SOLUTION: The internal combustion engine comprises a mechanism for lubrication to a cylinder wall to which a piston 2 slide-contacts. In the engine, there is provided an oil reservoir grooves 8 extending obliquely in the direction same as that of scavenging swirl in communication with a lubrication hole 6 having openings in the circumferential direction of the cylinder wall. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an internal combustion engine such as a marine diesel engine having a mechanism for lubricating a cylinder wall with which a piston slides.

[0002]

2. Description of the Related Art In a two-cycle marine diesel engine, lubricating oil is injected into a cylinder in accordance with the movement of a piston. The cylinder liner) is formed with a plurality of lubricating holes in the circumferential direction.

For example, as shown in FIG. 7, a lubrication hole 101 is simply formed in the radial direction of a cylinder (cylinder liner) 100 (in the case of FIG. 7 (a)), or an adjacent lubrication hole is formed.
101 comrades are communicated with each other through an inverted mountain shaped oil retaining groove 102 (Fig. 7).
(In the case of (b)). In FIG. 7, only one oiling hole 101 is shown for convenience of explanation.

However, the conventional lubrication hole 10 as described above is used.
In the case of 1, the cylinder (cylinder liner) 100 is opened in the radial direction, and the traveling direction of the lubricating oil is changed by 90 ° from the central direction to the circumferential direction. Therefore, the spreading property of the lubricating oil is poor and the pumping loss increases. There is a problem that the amount of lubricating oil consumed is also increased.

Therefore, in Japanese Utility Model Laid-Open No. 1-118113, the lubrication hole is directed to the inner surface of the cylinder liner in the same direction as the direction of the scavenging swirl, at a tangential direction to the inner surface of the cylinder liner, or at an angle close to the tangential direction, and further upward at a predetermined angle. What was opened by the applicant was disclosed by the present applicant, but there was still a problem that the spreadability of the lubricating oil was still poor.

The present invention has been made to solve such a problem, and an object of the present invention is to provide an internal combustion engine capable of improving the spreadability of lubricating oil and reducing the amount of lubricating oil consumed.

[0007]

An internal combustion engine according to the invention of claim 1 for achieving the above object is an internal combustion engine having an oiling mechanism for a cylinder wall on which a piston is slidably contacted, in a circumferential direction of the cylinder wall. It is characterized in that an oil retaining groove is provided, which communicates with a plurality of oil injection holes opened in the above and extends obliquely in the same direction as the direction of the scavenging swirl.

Further, the oiling hole is formed obliquely in the same direction as the direction of the scavenging swirl.

Further, the oil retaining groove is characterized in that the oil retaining groove has a length reaching almost directly above an adjacent oil injection hole.

Further, the oil retaining groove is characterized in that it is bent into a mountain shape from the middle and communicates with an adjacent oil injection hole.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, an internal combustion engine according to the present invention will be described in detail by way of embodiments with reference to the drawings.

[First Embodiment] FIG. 1 is an explanatory view of a piston position in each lubrication period in a two-cycle diesel engine according to a first embodiment of the present invention, and FIG. 2 is a graph of the same lubrication position and lubrication period. 3 is an explanatory view of the oil injection hole and the oil retaining groove.

As shown in FIG. 1, a piston 2 is accommodated in a cylinder 1 via a connecting rod 3 so as to be vertically movable (reciprocating). The exhaust port 4 opened in the upper wall portion of the cylinder 1 is opened and closed by an exhaust valve 5 at a predetermined timing. In the peripheral wall of the cylinder 1, a plurality of oiling holes 6 are formed in the circumferential direction at the intermediate portion in the vertical direction, and at the same time, the scavenging port 7 is positioned in the circumferential direction near the bottom dead center of the piston 2. A plurality of openings are formed.

As shown in FIG. 2, in the cylinder 1, the lubrication hole 6 is consciously provided at one stage of the compression stroke (see (a) of FIG. 1) and at the beginning of the combustion stroke (see (b) of FIG. 1). As the lubricating oil is further injected, the lubricating oil leaks from the oil injection hole 6 due to the decrease of the pressure in the cylinder 1 at one time (see (c) of FIG. 1) of the scavenging stroke.

As shown in FIG. 3, the lubrication hole 6 is formed obliquely in the same direction as the direction of the scavenging swirl (see the arrow in the swirl direction in the figure). In the illustrated example, the cylinder is opened at an oiling angle of about 45 ° and at an upward angle of about 25 ° when viewed from the front of the cylinder.

Then, an oil retaining groove 8 communicating with the oil filling hole 6 and extending obliquely in the same direction as the direction of the scavenging swirl is formed.

In this way, since the oil-filling hole 6 and the oil-retaining groove 8 are formed obliquely in the same direction as the direction of the scavenging swirl, the change in the traveling direction of the lubricating oil is reduced and the oil-filling hole 6 does not separate at the outlet. It can be put on a swirl flow to improve the spreadability of the lubricating oil.

In other words, as shown in FIG. 8 and FIG. 9, the conventional example is used regardless of whether only the lubrication hole 6 (circumferential hole) is provided or the oil retaining groove 8 (circumferential groove) is added. Compared with the above, if the amount of lubricating oil is the same, the circumferential spreading distance and spreading width of the lubricating oil increase.

It has been confirmed by experiments that it is desirable that the lubrication angle in the lubrication hole 6 and the oil retaining groove 8 be about 45 ° or less, as shown in FIGS.

[Second Embodiment] FIG. 4 is an explanatory view of an oil injection hole and an oil retaining groove according to a second embodiment of the present invention.

This is an example in which the oil-filling holes 6 opened in the radial direction of the cylinder 1 are communicated with each other by a mountain-shaped oil retaining groove 8 '.

According to this, the spreadability of the lubricating oil is improved by the interposition of the oil retaining groove 8'which obliquely extends in the same direction as the direction of the scavenging swirl.

[Third Embodiment] FIG. 5 is an explanatory view of an oil injection hole and an oil retaining groove according to a third embodiment of the present invention.

This is an example in which the oil-filling holes 6 in the first embodiment are communicated with each other by a mountain-shaped oil retaining groove 8 '.

According to this, the spreadability of the lubricating oil is improved by the synergistic effect of the oil injection hole 6 and the oil retaining groove 8'which extend obliquely in the same direction as the direction of the scavenging swirl.

Incidentally, FIG. 6 is a modification of the second and third embodiments. FIG. 6 (a) shows the oil retaining groove 8'of the second embodiment substantially directly above the oiling hole 6 adjacent thereto. This is an example in which a linear groove having a length reaching up to is formed, and FIG. 6B shows the oil injection hole 6 of the third embodiment.
In this example, the upward angle is set to zero (horizontal).

According to these, the same operation and effect as those of the second and third embodiments can be obtained.

The present invention is not limited to the above embodiments,
It goes without saying that various changes can be made without departing from the scope of the present invention.

[0029]

As described above in detail, according to the internal combustion engine according to the inventions of claims 1 to 4, in the internal combustion engine having the mechanism for lubricating the cylinder wall with which the piston is in sliding contact, the cylinder wall circumferential direction. Since the oil retaining groove that extends obliquely in the same direction as the direction of the scavenging swirl is provided so as to communicate with the plurality of oil filling holes, it is possible to improve the spreadability of the lubricating oil and reduce the amount of lubricating oil consumed.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a piston position in each lubrication period in a two-cycle diesel engine according to a first embodiment of the present invention.

FIG. 2 is a graph of the lubrication position and lubrication period.

FIG. 3 is an explanatory view of an oil injection hole and an oil retaining groove of the same.

FIG. 4 is an explanatory view of an oil injection hole and an oil retaining groove according to a second embodiment of the present invention.

FIG. 5 is an explanatory diagram of an oil injection hole and an oil retaining groove according to a third embodiment of the present invention.

FIG. 6 is a modification of the second and third embodiments.

FIG. 7 is an explanatory diagram of a conventional example.

FIG. 8 is a graph comparing the amount of oil supply and the circumferential spreading distance.

FIG. 9 is a graph comparing the amount of lubrication and the spread width.

FIG. 10 is a graph showing a relationship between an oiling angle and a circumferential spreading distance.

FIG. 11 is a graph showing the relationship between the lubrication angle and the spread width.

[Explanation of symbols]

1 cylinder 2 pistons 3 connecting rods 4 exhaust port 5 exhaust valve 6 Lubrication hole 7 Scavenger 8,8 'oil retaining groove

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yama-Saki-Yohei             1-1 1-1 Wadasaki-cho, Hyogo-ku, Kobe-shi, Hyogo             No. Mitsubishi Heavy Industries, Ltd.Kobe Shipyard F term (reference) 3G013 AA12 BA01 BA02 BC04 BD03                       CA17                 3G024 AA23 BA23 DA13 FA07

Claims (4)

[Claims] 1. An internal combustion engine having a mechanism for lubricating a cylinder wall with which a piston is in sliding contact, which communicates with a plurality of lubricating holes opened in the circumferential direction of the cylinder wall and extends diagonally in the same direction as the direction of the scavenging swirl. An internal combustion engine having an oil groove. 2. The internal combustion engine according to claim 1, wherein the oil injection hole is formed obliquely in the same direction as the direction of the scavenging swirl. 3. The internal combustion engine according to claim 1 or 2, wherein the oil retaining groove has a length that reaches substantially directly above an adjacent oil injection hole. 4. The internal combustion engine according to claim 1 or 2, wherein the oil retaining groove is bent into a mountain shape from the middle and communicates with an adjacent oil injection hole.