JPH04103812A - Breezer device of overhead valve engine - Google Patents

Abstract

PURPOSE:To satisfactorily feed oil to a rocker arm or a valve housed in a rocker arm chamber by providing a breezer passage for communicating a crank chamber with a push rod chamber on a half chamber part of a push rod chamber on a farer side from a breezer chamber. CONSTITUTION:An oil introducing passage 12 is formed between a cooling oil passage 11 and a front half chamber part 6c of a push rod chamber 6. A breezer passage 10 which is communicated with a crank chamber 8 is provided on a bottom of a half chamber part 6c on a farer side from a breezer chamber 9. Oil diffused into the crank chamber 8 is jetted from the breezer passage 10 together with blow-by gas, and sent to a rocker arm chamber 5. In addition, a part of oil which is used for cooling a cylinder part 2e is sent to the rocker arm chamber 5 through the cooling oil passage 11 and the oil introducing passage 12. Lubricating oil is thus satisfactorily fed to the rocker arm or valve on the farer side from the breezer chamber.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention is an overhead valve engine in which a cylinder part is cooled with oil. The present invention relates to a breather device that lubricates a rocker arm and a valve by providing an oil lead-out passage that communicates a cooling oil passage and a push rod chamber.

(Prior Art) Conventionally, some breather devices for overhead valve engines have the following configuration.

That is, a breather chamber is formed in the head cover at a position biased toward either the front or rear when viewed from the pair of front and rear rocker arms, and the breather chamber is communicated with the crank chamber via the push rod chamber and the rocker arm chamber in that order. A breather passage communicating between the push rod chamber and the push rod chamber was provided in the center of the push rod chamber in the longitudinal direction.

(Problem to be solved by the invention) The above conventional technology has the following problems.

Blowby gas flows from the crank chamber into the breather chamber through the push rod chamber and the rocker arm chamber in the longitudinal direction closer to the breather chamber, so the blowby gas flows into the rocker arm and valve on the side farther from the breather chamber. The problem was that it became difficult to flow and the lubricant was difficult to spread.

The present invention was made to solve the above problems, and
The purpose of this is to sufficiently distribute lubricating oil to the rocker arm and valve on the far side from the breather chamber.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a push rod chamber of a breather device for an overhead valve engine that cools a cylinder part with oil by separating a front chamber bone and a rear chamber bone by a partition wall. A breather passage communicating between the crank chamber and the push rod chamber is provided in the birth chamber part of the front chamber bone and the rear chamber bone on the side far from the breather chamber, and An oil outlet is formed to communicate the cooling oil passage with the part of the house on the far side.

(effect) The invention works as follows.

For example, as shown in FIGS. 1 to 4, the crank chamber 8
The oil scattered inside is carried by the blow-by gas, passes through the breather passage 10, and gushes out with force, and flows into the push rod chamber 6.
It goes from the front half chamber bone 6C through the front half of the rocker arm chamber 5 to the breather chamber 9. In addition to this, cooling oil passage 1
The oil that has passed through the oil outlet path 12 from the push rod chamber 6 toward the front chamber bone 6C also heads toward the rocker arm chamber 5 on the blow-by gas. In other words, breather passage 1
The amount of oil that has passed through the oil outlet path 12 is greater than when only 0 is present.

In the rocker arm chamber 5, as shown by the arrow in FIG.
d and around the intake valve 3b in the same way, allowing a sufficient layer of oil to be spread around them.

(Example) Embodiments of the present invention will be described below with reference to FIGS. 1 to 5.

1 to 4 show a vertical overhead valve diesel engine 1 which is an embodiment of the present invention, in which a cylinder head 3 is fixed to the upper part of a cylinder block 2 via a head gasket 13. A head cover 4 is provided.

A piston 2b inserted into a cylinder liner 2a of the cylinder block 2 is connected to a crankshaft 2c via a connecting rod 2d.

A cooling oil passage 11 is formed between the cylinder portion 2e and the push rod chamber 6. In addition, the push rod chamber 6
A cooling oil return passage 14 is formed in the center of the cooling oil return passage 14 . moreover,
Cooling oil passage 11 and front half chamber bone 6c of push rod chamber 6
A slit-shaped oil outlet passage 12 is formed on the upper surface of the cylinder block 2 between the cylinder block 2 and the cylinder block 2 .

The cylinder head 3 has an intake port 3d and an exhaust port 3.
e is formed and includes a fuel injection nozzle 3as, an intake valve 3b, an exhaust valve 30, and the like.

The head cover 4 forms a rocker arm chamber 5 by covering the valve springs 4aΦ4b10, the lever arms 4c and 4d, and the push rods 6a and 6b. Rocker arm chamber 5
The breather chamber 9 is located at a position biased towards the rear side when viewed from the pair of front and rear rocker arms 4c and 4d.

The push rod chamber 6 is formed across the cylinder block 2 and the cylinder head 3, and is divided by a partition wall 7 projecting to one side of the central portion into a front chamber rib 6C and a rear chamber bone 6d, which communicate with each other. And breather room 9
At the bottom of the front half chamber part 6C on the side far from the crank chamber 8
A breather passage 10 is provided which communicates with the air conditioner. Further, the partition wall 7 is formed of a cylinder head portion 7a and a cylinder block portion 7b, and a cooling oil return passage 14 communicates with the cylinder block portion 7b to the crank chamber 8.

Oil in an oil pan (not shown) is pumped by an oil pump, enters the cooling oil passage 11 through the entrance hole 11a, cools the cylinder portion 2e, and returns to the crank chamber 8 through the cooling oil return passage 14 from the outlet 11b.

The push rods 6a and 6b penetrate the cylinder head 3 and the cylinder block 2, pass through the front housing portion 6C and the rear housing portion 6d of the push rod chamber 6, and are connected to the crankshaft by a gear (not shown) in the crank chamber 8. The intake valve 3b and the exhaust valve 3C are moved by the valve driving cam 8a which rotates in conjunction with the valve 2C, and the intake valve 3b and the exhaust valve 3C are moved through the rocker arms 4c and 4d.
move.

In the embodiment of the present invention having such a configuration, as described above, the oil splashed into the crank chamber 8 is carried by the blow-by gas, passes through the breather passage 10, and is vigorously blown out, causing the oil to flow into the front housing portion 6C of the push rod chamber 6. from the rocker arm chamber 5 to the breather chamber 9, but in addition, the cylinder section 2
A part of the oil that has cooled the oil flows from the cooling oil passage 11 toward the front flat chamber portion 6C of the push rod chamber 6 through the oil outlet passage 12.
Go through it and ride the blow-by gas to rocker arm room 5. In other words, the amount of oil that has passed through the oil outlet path 12 is greater than when only the breather path 10 is used.

Inside the rocker arm chamber 5, as shown by the arrow in FIG.
The blow-by gas spreads in the same way around the rocker arm 4c and exhaust valve 3C on the side far from the breather chamber 9, and around the rocker arm 4d and intake valve 3b on the side close to the breather chamber 9, so that a sufficient layer of oil can be spread around them. I can do it.

Incidentally, the oil outlet path 12 may be hole-shaped instead of slit-shaped, and the partition wall 7 is not just one side protruding, but both sides are connected, so that the front part 6c and the later part 6d are connected.
The same effect can be obtained even if the shape is such that the two are completely separated.

FIG. 5 shows another embodiment of the oil outlet path 12.
2 is formed by the notch 13a of the head gasket 13.

In this case as well, the oil outlet path 12 may be a recess formed in the upper surface or lower surface of the head gasket 13, or both surfaces thereof, instead of the head gasket notch 13a.

(Effects of the Invention) In the present invention, a breather passage that communicates the crank chamber and the push rod chamber is provided in the half chamber of the push rod chamber on the side far from the breather chamber. It can also be distributed to the rocker arm chamber part on the far side. Furthermore, since an oil outlet path is provided that communicates the cooling oil passage with the bullock cart portion of the push rod chamber, the supply of oil to the blow-by gas can be increased. Therefore, it has become possible to more sufficiently distribute the oil to the rocker arm and the valve housed in the rocker arm chamber.

[Brief explanation of the drawing]

1 to 4 show one embodiment of the present invention, in which FIG. 1 is a sectional view taken along the line I-I in FIG. 2, FIG. 2 is a longitudinal sectional view of the overhead valve engine 1, and FIG. is a sectional view taken along line mm in FIG. 2,
4 is a plan view taken along the line IV--IV in FIG. 2. FIG. Fifth
The figure shows another embodiment, and is a partial plan view of a cylinder block and a head gasket. 1... Overhead valve engine, 2e... Cylinder part, 4.
・・Head cover, 4c・4d・・Rocker arm,
5... Rocker arm chamber, 6... Push rod chamber,
6c...Previous house part, 6d...Postnatal house part, 7...
・Inner partition wall, 8... Crank chamber, 9... Breather chamber, 10... Breather passage, 11... Cooling oil passage, 1
2...Oil outlet path, 13...Head gasket.

Claims (1)

[Claims] 1. In the cylinder block 2 of the overhead valve engine 1, the cylinder part 2 is located between the cylinder part 2e and the push rod chamber 6.
A cooling oil passage 11 for oil-cooling the engine is provided, a breather chamber 9 is formed in the head cover 4 at a position biased toward either the front or rear when viewed from the pair of front and rear rocker arms 4c and 4d, and a push rod chamber is provided in the crank chamber 8. In the breather device for an overhead valve engine configured by connecting a breather chamber 9 via the push rod chamber 6 and the rocker arm chamber 5 in order, the push rod chamber 6 is
It is divided into a front chamber part 6c and a rear chamber part 6d by the partition wall 7, and a crank chamber 8 is placed in the half chamber part 6c on the side far from the breather chamber 9, of the front chamber part 6c and the rear chamber part 6d.
The overhead device is characterized in that a breather passage 10 is provided which communicates the push rod chamber 6 with the breather chamber 9, and a cooling oil passage 11 is connected to the half chamber portion 6c on the side far from the breather chamber 9 through an oil outlet passage 12. Valve engine breather device. 2. A breather device for an overhead valve engine according to claim 1, wherein the oil outlet passage 12 is formed in a head gasket 13.