JPH051518A - V-type engine lubrication structure - Google Patents

Abstract

PURPOSE:To increase a discharge quantity of lubrication oil. perform a temperature control to discharged lubrication oil by cooling water, decrease its viscosity in starting an engine so as to let it flow more easily, and restrict an excessive temperature rise for an engine high load so as to prevent oil deterioration. CONSTITUTION:A lubrication oil discharge passage 52 is formed at a V-letter shaped bank part 50 between cylinders 10, 12 facing each other. The inside of head covers 64, 66 is connected with the lubrication oil discharge passage 52 through oil return passages 68, 701. Cooling water passages 58, 60 are formed corresponding to parts where the lubrication oil discharge passage 52 is formed inside cylinder walls 54, 56 separating the V-letter shaped bank part 50.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lubricating structure for a V-type engine, and more particularly to a lubricating structure for the inside of a cylinder head.

[0002]

2. Description of the Related Art As a so-called V-type engine in which opposed cylinders are arranged in a V shape, for example, Japanese Utility Model Publication No. 62-3793.
Some are disclosed in Japanese Patent Publication No. In this V-type engine, the valve mechanism is housed inside each cylinder head,
This valve mechanism opens and closes the intake and exhaust valves.

A large amount of lubricating oil is supplied to the valve operating mechanism to make it operate smoothly, and the lubricating oil after lubrication is drained to an oil pan through an oil return passage. .

[0004]

However, in the conventional lubrication structure, the oil return passage for draining the lubricating oil of the valve mechanism is usually formed in the thick portion of the cylinder block by machining such as drilling. . For this reason, the cross-sectional area of the oil return passage cannot be increased sufficiently, and the flow resistance of the return oil increases. Therefore, the amount of lubricating oil supplied to the valve mechanism is naturally determined, and it becomes impossible to supply a large amount of lubricating oil.

Further, when the engine is started, the viscosity of the lubricating oil is high, the flow resistance in the oil return passage is further increased, and the drain amount of the lubricating oil is significantly reduced.

In view of such conventional problems, the present invention focuses on a V-type engine structure in which opposed cylinders are arranged in a V-shape, and utilizes a V-shaped bank portion between opposed cylinders to provide a large amount. The lubricating structure of the V-type engine that reduces the viscosity of the lubricating oil and makes it easier to flow by heating the lubricating oil to be discharged by the cooling water whose temperature rises greatly at the time of engine startup. The purpose is to provide.

[0007]

To achieve the above object, the present invention provides a V-shaped bank formed between opposed cylinders in a V-type engine lubrication structure in which opposed cylinders are arranged in a V-shape. Form a lubricating oil discharge passage in the section,
A cooling water passage is formed inside the cylinder wall that defines the lubricating oil discharge passage, corresponding to the position where the lubricating oil discharge passage is formed.

Further, it is preferable that a vacuum chamber for introducing a negative pressure of the intake passage is provided in the V-shaped bank portion, and a housing of the vacuum chamber closes an upper portion of the lubricating oil discharge passage.

[0009]

In the lubricating structure for the engine of the present invention having the above-described structure, the lubricating oil discharge passage is formed in the V-shaped bank portion between the opposed cylinders to increase the cross-sectional area of the lubricating oil discharge passage. By securing it, it is possible to significantly increase the amount of lubricating oil discharged. Further, the lubricating oil flowing through the lubricating oil discharge passage easily exchanges heat with the cooling water flowing through the cooling water passage formed in the cylinder wall. For this reason, when the engine is started, the temperature of the lubricating oil to be discharged is raised by cooling water having a large temperature rise rate to lower its viscosity,
Distribution resistance can be significantly reduced. On the other hand, when the lubricating oil temperature rises excessively, the lubricating oil can be prevented from deterioration by cooling with the cooling water.

Further, by closing the upper portion of the lubricating oil discharge passage with the housing of the vacuum chamber,
By using the vacuum chamber as the closing member of the lubricating oil discharge passage, the number of parts can be reduced and the weight can be reduced. Further, by disposing the vacuum chamber above the lubricating oil discharge passage, the distance between the vacuum chamber and the intake passage can be shortened, and the resistance to the introduction of negative pressure can be reduced.

[0011]

Embodiments of the present invention will now be described in detail with reference to the drawings. 1 and 2 show an embodiment of an engine lubrication structure according to the present invention, and FIG. 1 is a sectional front view of an essential part, FIG.
FIG. 2 is a sectional view of a main part corresponding to line AA in FIG. 1.

That is, the lubrication structure of this embodiment is applied to a so-called V-type engine 14 in which the opposed cylinders 10 and 12 form a V-shape. Valve operating mechanisms 20 and 22 are provided inside the cylinder heads 16 and 18 of the V-type engine 14, and the valve operating mechanisms 20 and 22 open and close the intake valves 24 and 24 and the exhaust valves 26 and 26.

The valve operating mechanisms 20 and 22 will be described by taking the one valve operating mechanism 20 shown on the left side of the drawing as an example.
Camshafts 28 and 30 provided for intake and exhaust, respectively
, Rocker arms 32, 34, oil tappet 36,
38 and the supply and exhaust valves 24, 26 and the like. still,
In the other valve operating mechanism 22 shown on the right side of the drawing, detailed illustration of the components is omitted, but this valve operating mechanism 22 has the same configuration as that of the one valve operating mechanism 20 and has the same structure. The same reference numerals will be given and described below.

The intake passages 40, 40 for opening / closing the intake valves 24, 24 are arranged inside the V-type engine 14, respectively, and the exhaust passages 42, 4 for opening / closing the exhaust valves 26, 26 are provided.
2 are arranged outside respectively. The intake passages 40, 40
Each of them is provided with a variable intake control valve 44, and an actuator 46 for driving the variable intake control valve 44.
The intake passage 4 through the vacuum chamber 48.
A negative pressure in 0,40 is introduced.

Here, in this embodiment, the opposed cylinder 1 is used.
A lubricating oil discharge passage 52 is formed in the V-shaped bank portion 50 formed between 0 and 12. Also, this lubricating oil discharge passage 5
2 is defined by the cylinder walls 54 and 56 of the cylinders 10 and 12, and cooling water passages 58 and 60 are formed inside the cylinder walls 54 and 56, respectively, corresponding to the positions where the lubricating oil discharge passages 52 are formed. To do.

The upper portion of the lubricating oil discharge passage 52 is open, but the vacuum chamber 48 is
Is formed in advance according to the shape of the open portion 62, and the open portion 62 of the lubricating oil discharge passage 52 is closed by the housing 48a of the vacuum chamber 48.

By the way, in the upper portion of the lubricating oil discharge passage 52, as shown in FIG.
Oil return passages 68, 70 communicating with the interiors of the head covers 64, 66 accommodating the
The lubricating oil that lubricates 2 is the oil return passage 68, 7
Through 0 into the lubricating oil discharge passage 52. And
The lubricating oil that has flowed out to the lubricating oil discharge passage 52 flows rightward in the drawing through the lubricating oil discharge passage 52 as shown in FIG. 2, and is between the end plate 74 that closes the right end of the cylinder block 72 in the drawing. It is returned to the crank chamber (not shown) through the gap portion δ.

A main journal 76 for supplying lubricating oil is formed at the lower end of the V-shaped bank portion 50, and the valve operating mechanisms 20 and 22 are connected to the valve operating mechanisms 20 and 22 through a passage (not shown) branched from the main journal 76. Supply lubricating oil to each. Further, as the V-type engine 14 of the present embodiment, a slant engine in which the crankshaft is inclined so that the lubricating oil discharge passage 52 is inclined downward to the right in the figure is adopted.

In the lubricating structure of the V-type engine according to the present embodiment having the above structure, the V between the opposed cylinders 10 and 12 is
Since the lubricating oil discharge passage 52 is formed in the V-shaped bank portion 50, the cross-sectional area of the lubricating oil discharge passage 52 can be enlarged. Further, the lubricating oil discharge passage 52 has the cylinder head 1
The oil return passages 68 and 70 that connect the lubricating oil discharge passage 52 and the head covers 64 and 66 to each other by being arranged in the vicinity of 6 and 18 can be remarkably short. Therefore, the oil return passage 6
Even when 8 and 70 are formed to have a small diameter by machining, shortening the oil return passages 68 and 70 can significantly reduce the flow resistance of the lubricating oil.

Therefore, the cross-sectional area of the lubricating oil discharge passage 52 is enlarged, and the oil return passages 68, 70 are
By shortening, the flow rate of the lubricating oil discharged through the lubricating oil discharge passage 52 is significantly increased, and as a result, the amount of lubricating oil supplied to the valve operating mechanisms 20 and 22 is increased. You can

Further, since the cylinder walls 54 and 56 defining the V-shaped bank portion 50 are formed with the cooling water passages 58 and 60 corresponding to the positions where the lubricating oil discharge passage 52 is formed,
This facilitates heat exchange between the lubricating oil discharge passage 52 and the cooling water passages 58 and 60. Therefore, when the temperature of the lubricating oil is low and the viscosity is extremely high at the time of starting the engine, the lubricating oil is rapidly heated by the cooling water having a large temperature rise rate to reduce the viscosity, and the lubricating oil discharge Aisle 52
It is possible to increase the amount of lubricating oil discharged through the. On the other hand, when the lubricating oil temperature is excessively increased due to high load operation of the engine or the like, the lubricating oil can be cooled by the cooling water to prevent deterioration of the lubricating oil.

By the way, the opening 62 of the lubricating oil discharge passage 52 is connected to the housing 48a of the vacuum chamber 48.
Since the vacuum chamber 48 can be used also as the closing member of the lubricating oil discharge passage 52, the number of parts can be reduced and the weight can be reduced accordingly. Further, by disposing the vacuum chamber 48 in the lubricating oil discharge passage 52, the distance between the vacuum chamber 48 and the intake passages 40, 40 can be shortened, and the intake chambers 40, 40 can be changed to the vacuum chamber 48. The resistance at the time of introducing the negative pressure can be significantly reduced, and the responsiveness at the time of driving the actuator 46 can be improved.

Although the engine 14 of the present embodiment has been disclosed as a case where the present invention is applied to a V-type 8-cylinder engine having four cylinders on one side as shown in FIG. 2, the present invention is not limited to this. In particular, in the present embodiment, the effect can be greatly exerted by being applied to the engine in which the lubricating oil discharge path becomes long, and, for example,
The present invention can be applied to a large engine such as a V-type 10 cylinder or a V-type 12 cylinder.

[0024]

As described above, in the lubricating structure for the V-type engine according to the first aspect of the present invention, the lubricating oil discharge passage is formed in the V-shaped bank portion between the opposed cylinders of the V-type engine. Since the lubricating oil after lubricating the valve operating mechanism of the cylinder head is discharged through the lubricating oil discharge passage, the cross-sectional area of the lubricating oil discharge passage can be set large, so that the lubricating oil discharge amount can be reduced. A large increase can be achieved, and as a result, the amount of lubricating oil supplied to the valve mechanism can be increased. Further, since the cooling water passage is formed inside the cylinder wall that defines the lubricating oil discharge passage at the position where the lubricating oil discharge passage is formed, the cooling water flowing through the cooling water passage and the lubricating oil discharge passage are formed. The heat exchange rate with the lubricating oil flowing through can be improved. Therefore, when the engine is started, the temperature of the lubricating oil is increased to increase the viscosity, the flow resistance of the lubricating oil is further reduced, and the lubricating oil temperature is prevented from rising abnormally under high engine load conditions. It is possible to prevent deterioration.

According to the second aspect of the present invention, since the upper part of the lubricating oil discharge passage is closed by the housing of the vacuum chamber for introducing the negative pressure of the intake passage, the vacuum chamber also serves as a closing member. The number of points and the weight can be reduced. Further, the vacuum chamber can be arranged in the V-shaped bank portion in which the lubricating oil discharge passage is formed, and the distance between the vacuum chamber and the intake passage can be shortened to reduce the resistance when the negative pressure is introduced. It has various excellent effects.

[Brief description of drawings]

FIG. 1 is a sectional front view of a main part showing an embodiment of a lubricating structure for a V-type engine according to the present invention.

FIG. 2 is a cross-sectional view of relevant parts taken along the line AA in FIG.

[Explanation of symbols]

10, 12 cylinder 14 V-type engine 16, 18 cylinder head 20, 22 valve mechanism 40 intake passage 42 exhaust passage 48 vacuum chamber 50 V-shaped bank portion 52 lubricating oil discharge passage 54, 56 cylinder wall 58, 60 cooling water passage 62 Openings 64, 66 Head cover 68, 70 Oil return passage

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI Technical display area F02F 1/00 Z 8503-3G

Claims (2)

[Claims] 1. A lubrication structure for a V-type engine in which opposed cylinders are arranged in a V shape, and a lubricating oil discharge passage is formed in a V-shaped bank portion formed between opposed cylinders.
A lubricating structure for a V-type engine, characterized in that a cooling water passage is formed inside a cylinder wall defining the lubricating oil discharge passage so as to correspond to a position where the lubricating oil discharge passage is formed. 2. The V-shaped bank portion is provided with a vacuum chamber for introducing a negative pressure of the intake passage, and the housing of the vacuum chamber closes the upper portion of the lubricating oil discharge passage. Lubricating structure of the described V-type engine.