JP2518936Y2 - Engine oil separator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to an oil separator for an engine that performs gas-liquid separation on the upper surface of a cylinder head cover on the valve chamber side of a tilted engine.

[Problems to be Solved by Conventional Techniques and Inventions] Generally, in a 4-cycle engine, blow-by gas filled in a crank chamber and a valve operating chamber is returned to an intake system by utilizing an increase in crank chamber pressure. However, since the blow-by gas contains mist-like oil, it is necessary to perform gas-liquid separation before reducing it to the intake system.

Many oil separators for separating the mist-like oil contained in the blow-by gas are provided on the upper surface of the cylinder head cover on the valve operating chamber side where the mist-like oil contained in the blow-by gas is the smallest.

For example, in the oil separator disclosed in Japanese Utility Model Laid-Open No. 59-79510, blow-by gas is blown from the blow-by gas intake port arranged directly above the cam holder to the oil separator chamber provided on the upper surface of the cylinder head cover on the valve chamber side. The mist-like oil is introduced here, and after being separated in a predetermined manner, it is returned to the intake system from the discharge port.

However, in the oil separator shown in this prior art, excessive mist-like oil easily flows directly into the oil separator chamber, and a sufficient gas-liquid separation capacity cannot be obtained.

Further, in a so-called tilted engine (including a V-shaped engine and a horizontally opposed engine) in which the cylinder axis is tilted, a large amount of oil after separation stays in the oil separator chamber, and this staying oil is the blow-by gas. Therefore, it is likely to be led out to the intake system, and as a result, a problem occurs that the amount of mist-like oil discharged to the intake system increases.

[Object of the Invention] The present invention has been made in view of the above circumstances, and provides an oil separator for an engine that can significantly reduce the amount of oil mist discharged to the intake system and obtain excellent gas-liquid separation performance. The purpose is to do.

[Means for Solving the Problems] The oil separator according to the present invention is provided with an outer frame rib protruding to the inner wall surface of the top of the cylinder head cover in the valve operating chamber of the cylinder head of the engine in which the cylinder axis is inclined in one direction. In an oil separator of an engine having an oil separator chamber formed by a partition plate joined to an end portion of the outer frame rib, a part of the outer frame rib is provided opposite to a side inner wall surface of the cylinder head cover. At the same time, a blow-by gas inlet to the oil separator chamber is formed at a position offset to the inclined side of the cylinder axis in a part of the rib, and an oil shield plate is provided directly below the blow-by gas inlet of the partition plate to the cylinder. The head cover is arranged so as to face the inner wall surface of the side portion of the head cover, and faces the blow-by gas intake in the oil separator chamber. It is provided with an oil return guide part which becomes a downward slope.

[Operation] With the above configuration, the blow-by gas intake port is provided opposite to the inner wall surface of the cylinder head cover, and the oil shield plate is vertically provided in the partition plate at a position corresponding to the blow-by gas intake port toward the valve operating chamber. As a result, the mist-like oil flowing into the oil separator chamber is restricted.

Further, by providing the oil return guide portion that is inclined downward toward the blow-by gas intake port in the oil separator chamber, oil is returned to the valve operating chamber without staying in the oil separator chamber.

[Embodiments of the present invention] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

The drawings show one embodiment of the present invention. Fig. 1 is a bottom view of a cylinder head cover, Fig. 2 is a bottom view corresponding to Fig. 1 with a partition plate removed, and Fig. 3 is III- of Fig. 1. III sectional view, FIG. 4 is a longitudinal sectional view of an essential part of the engine body, FIG. 5 is a VV sectional view of FIG. 2, and FIG. 6 is a VI-VI sectional view of FIG.
7 is a sectional view taken along line VII-VII in FIG. 2, and FIG. 8 is VII in FIG.
FIG. 9 is a sectional view taken along the line IX in FIG. 1, and FIG.
It is an X section sectional view of the figure.

(Structure) In FIG. 4, reference numeral 1 in the drawing denotes an inclined engine, the cylinder axis CL of which is inclined, and the cylinder block 2
The cylinder head 3 is attached to the top surface of the.

Further, a cylinder head cover 4 is provided on the cylinder head 3, and a valve operating chamber 5 is formed inside the cover.

A cam shaft 6 is rotatably provided horizontally in the valve operating chamber 5, and a rocker shaft 7 is provided directly above it.

A rocker arm 8 is pivotally supported on the rocker shaft 7,
A slipper portion 8a formed at one end of the rocker arm 8 is slidably contacted with the cam 6a of the cam shaft 6, and an adjuster 9 provided at the other end is pressed against the stem end of the intake valve 10 or the exhaust valve 11. ing.

An oil separator chamber 12 is provided on the inner surface of the top of the cylinder head cover 4. 1 to 3
As shown in the figure, the oil separator chamber 12 includes ribs 4a, 4 protruding from the inner surface of the top of the cylinder head cover 4.
It is composed of b and 4c and a partition plate 13.

The rib 4a is the outer frame portion 12 of the oil separator chamber 12.
A and a partition wall portion 12b for partitioning substantially the center of the oil separator chamber 12 along the camshaft 6 are formed (hatched portion by solid line in FIG. 2). Further, blow-by gas intake ports 12c are opened on both side surfaces of the outer frame portion 12a located on the axial end side of the camshaft 6 at positions biased toward the inclined side of the cylinder axis CL.

Further, the blow-by gas intake port 12c is formed opposite to the inner wall surface 4d of the cylinder head cover 4 extending toward the cylinder head 3 side, and is formed in a trapezoidal shape that is widened toward the valve operating chamber 5 side. There is.

Further, the rib 4b, the baffle plate portion 12d forming the blow-by gas flow passage of the oil separator chamber 12, and the oil return guide portion 12e for reducing the liquefied mist-like oil.
(Hatched portion by broken line in FIG. 2).

As shown in FIG. 2, a plurality of baffle plates 12d formed by the ribs 4b have a predetermined space between the outer frame 12a and the partition wall 12b located on the opposite side to the inclined side of the cylinder axis CL. The baffle plates 12d are opened and arranged in a zigzag manner, and a communication port 12f is opened between the edge of each baffle plate 12d and the outer frame part 12a or the partition wall part 12b opposite thereto. further,
The wall surface 12g of the baffle plate portion 12d at the right end in FIG. 2 is formed in a curved shape so as to guide the blow-by gas to the side of the flow port 12f.

In addition, the oil return guide portion 12e is connected to the partition wall portion 12b.
And the outer frame portion 12a located on the inclined side of the cylinder axis CL. The oil return guide portion 12e connects the partition wall portion 12b formed in the substantially central portion of the cylinder head cover 4 and the blow-by gas intake port 12c, and descends toward the blow-by gas intake port 12c. It has such an inclination.

Further, a plurality of ribs 4c are provided so as to project the inner wall surface 4d of the cylinder head cover 4, the outer frame portion 12a, the partition wall portion 12b, and the oil return guide portion 12e so as to reinforce each other. The portion of the rib 4c that protrudes into the oil separator chamber 12 also serves as the gas-liquid separation wall portion 12h.

Further, a plurality of oil return ports 12i are opened in the middle of the partition wall portion 12b.

Further, in FIG. 2, a blow-by gas outlet 12j is opened in a portion surrounded by the outer frame portion 12a and the partition wall portion 12b on the right side of the oil separator chamber 12 in a U shape. Further, the blow-by gas outlet 12j is communicated with a nipple 14 formed on the upper surface of the cylinder head cover 4, and the nipple 14 is connected to an expansion chamber (not shown) of an air cleaner which is a part of an intake system via a hose (not shown). Is in communication with.

Further, as shown in FIGS. 5 to 7, the ribs 4a, 4
The height H of b is equal, and the height h of the rib 4c is relatively low.

Further, a groove 4e is formed on the end surface of the rib 4a, and ridge portions 4f are provided upright on both sides of the groove 4e. Further, the partition plate 13 is fixed in contact with the ribs 4f of the rib 4a and the ends of the rib 4b. This partition plate 13 is formed of a resin molded product in a shape substantially along the outer frame 12a formed by the ribs 4a, and at a position facing the blow-by gas intake port 12c of the partition plate 13, an oil shield plate 13a is provided. The cylinder head cover 4 is vertically installed so as to face the inner wall surface 4d.

The partition plate 13 is fused to the end surface of the rib 4f of the rib 4a by frictional heat due to vibration, or adhered via an adhesive agent.

(Operation) Next, the operation of the embodiment having the above configuration will be described.

When the engine operates, the pressure in the crank chamber (not shown) fluctuates as the piston reciprocates.

When the crank chamber has a positive pressure, the blow-by gas filled in the crank chamber passes through a blow-by gas passage (not shown) formed in the cylinder block 2 and is formed in the cylinder head cover 4 attached to the cylinder head 3. Flow into the valve operating chamber 5.

Then, the blow-by gas flows into the oil separator chamber 12 from the blow-by gas intake port 12c opened on the axial end side of the camshaft 6.

Since the blow-by gas intake port 12c is provided in the upper part of the valve operating chamber 5 and faces the inner wall surface 4d of the cylinder head cover 4, the mist-like oil mixed in the blow-by gas is the inner wall surface 4d. Are collided with and dropped. Therefore, the amount of mist-like oil contained in the blow-by gas flowing into the oil separator chamber 12 is limited.

Further, during operation of the engine, the cam shaft 6 arranged in the valve operating chamber 5 rotates, and oil is scattered in the valve operating chamber 5 by driving the valve operating system. Therefore, although the oil scattered by the camshaft 6a and the valve operating system easily flows into the oil separator chamber 12 from the blow-by gas intake port 12c, the oil is scattered from the partition plate 13 at the blow-by gas intake port 12c. The scattered oil collides with the oil shield plate 13a and drops into droplets.
Inflow of oil to 12c is blocked.

On the other hand, the blow-by gas intake port 12 on the left side of the drawing in FIG.
The blow-by gas flowing in from c is branched in the vertical direction of the figure with the partition wall portion 12b as a boundary, and the blow-by gas branched upward is formed by the outer frame portion 12a, the partition wall portion 12b, and the baffle plate portion 12d. The gas passes through the gas passage, and in the meanwhile, it collides with the baffle plate portion 12d, the gas-liquid separation wall portion 12h, and the like, and advances in the right direction in the drawing while causing the mist-like oil contained in the blow-by gas to drop.

In addition, blow-by gas that flows into the lower side of the partition wall portion 12b as a boundary collides with the gas-liquid separation wall portion 12h or the like to separate mist-like oil, and an oil return port formed in the middle of the partition wall portion 12b. It flows into the oil separator chamber 12 above the partition wall portion 12b from 12i.

Furthermore, the blow-by gas intake on the right side of the drawing in FIG.
The blow-by gas flowing in from 12c proceeds along the blow-by gas passage formed by the oil return guide portion 12e and the partition wall portion 12b, and during that time, it collides with the gas-liquid separation wall portion 12h provided in the blow-by gas passage. While separating the mist-like oil through the oil return passage 12i formed in the middle of the partition wall portion 12b, it flows into the upper oil separator chamber 12 with the partition wall portion 12b as a boundary.

Then, the blow-by gas that has flowed through the oil separator chamber 12 and separated the mist-like oil rises along the wall surface 12g of the baffle plate portion 12d formed into a curved surface, and the flow port 12
After passing f, it flows to the blow-by gas outlet 12j.

Since the blow-by gas flows into the oil separator chamber 12 from both sides, gas-liquid separation efficiency is good.

On the other hand, the mist-like oil droplets in the oil separator chamber 12 is transmitted through the partition plate 13, the outer frame portion 12a, the partition wall portion 12b, the baffle plate portion 12d, and the gas-liquid separation wall portion 12h to the partition wall portion 12b. The oil is returned from the formed oil return port 12i to the oil return guide portion 12e.

Then, the oil dripping on the oil return guide 12e flows to the blow-by gas intake 12c on the downstream side along the inclined oil return guide 12e, and from the blow-by gas intake 12c, the valve operating chamber Reduced to 5.

As a result, the oil separated in the oil separator chamber 12 is sequentially returned to the valve operating chamber 5, so that the oil does not stay in the oil separator chamber 12 and the blow-by gas causes the blow-by gas outlet 12i. It is not carried to the side, has excellent gas-liquid separation capability, and reduces the amount of oil mist discharged to the intake system such as an air cleaner.

Further, the blow-by gas flowing out from the blow-by gas outlet 12j flows into the expansion chamber of the air cleaner via a hose connected to the nipple 4e and is reburned.

In FIG. 1, the flow of blow-by gas in the oil separator chamber 12 is shown by a dashed arrow, and the separated oil flow is shown by a two-dot chain line arrow.

Further, the engine oil separator according to the present invention,
V-shaped engine whose cylinder axis is inclined, or
It is also effective for horizontally opposed engines.

[Advantages of the Invention] As described above, according to the present invention, a part of the rib for the outer frame forming the oil separator chamber is opposed to the inner wall surface of the side of the cylinder head cover, and a part of the rib is formed. A blow-by gas inlet to the oil separator chamber is formed at a position offset to the inclined side of the cylinder axis, and an oil shield plate is hung vertically toward the valve operating chamber at a position corresponding to the blow-by gas inlet on the partition plate. Because I did
The mist-like oil contained in the blow-by gas collides with the oil shield plate and the side wall surface of the cylinder head cover at the side of the blow-by gas when it flows into the blow-by gas intake port, and is thus droplets. The inflow of oil is restricted.

In addition, since the oil return guide portion that is a downward slope toward the blow-by gas intake is provided in the oil separator chamber, the oil droplets in the oil separator chamber is along the slope of the oil return guide portion. Flow toward the blow-by gas intake port and are discharged from the blow-by gas intake port, so that the oil is returned to the valve operating chamber without remaining in the oil separator chamber.

As a result, the amount of oil mist discharged to the intake system can be greatly reduced, and excellent gas-liquid separation performance can be obtained.

[Brief description of drawings]

The drawings show one embodiment of the present invention. Fig. 1 is a bottom view of a cylinder head cover, Fig. 2 is a bottom view corresponding to Fig. 1 with a partition plate removed, and Fig. 3 is III- of Fig. 1. III cross section,
FIG. 4 is a longitudinal sectional view of an essential part of the engine body, FIG. 5 is a VV sectional view of FIG. 2, FIG. 6 is a VI-VI sectional view of FIG.
Fig. 7 is a sectional view taken along the line VII-VII in Fig. 2, Fig. 8 is a sectional view taken along the line VIII in Fig. 1, Fig. 9 is a sectional view taken along the line IX in Fig. 1, and Fig. 10 is a sectional view taken along the line X in Fig. 1. Is. 1 ... inclined engine, 3 ... cylinder head, 4 ... cylinder head cover, 4d ... inner wall surface, 5 ... valve chamber, 12
…… Oil separator chamber, 12a …… Outer frame part (outer frame rib), 12c …… Blow-by gas intake port, 12e …… Oil return guide part, 13 …… Partition plate, 13a …… Oil shield plate, CL… …
Cylinder axis.

Claims (1)

(57) [Scope of utility model registration request] 1. A rib for an outer frame protruding to an inner wall surface of the top of a cylinder head cover and an end portion of the rib for the outer frame are joined in a valve operating chamber of a cylinder head of an engine having a cylinder axis inclined in one direction. In an engine having an oil separator chamber formed by a partition plate, a part of the rib for the outer frame is opposed to a side inner wall surface of the cylinder head cover, and a part of the rib is on the inclined side of the cylinder axis. A blow-by gas inlet to the oil separator chamber is formed at a deviated position, and an oil shield plate is arranged directly below the blow-by gas inlet of the partition plate so as to face the side inner wall surface of the cylinder head cover. An engine characterized in that an oil return guide part which is a downward slope toward the blow-by gas intake is provided in the oil separator chamber. Oil separator.