AIR-OIL SEPARATOR WITH INTEGRATED ORIFICE STRIKER IN CYLINDER HEAD COVER

FIELD OF INVENTION

The present invention relates to an engine crankcase ventilation system, and more particularly to a cylinder head cover constructed with bay walls and integrated orifice striker for facilitating improved separation of oil particulates from the blow-by gases from the engine.

BACKGROUND OF THE INVENTION

The blow-by gas flowing passages for an internal combustion engine are formed to separate or remove the oil particulates from the blow-by gas and further to pass the oil separated blow-by gas into the intake system. The blow-by gas is a gas blowing into a crank case through spaces between the pistons and the cylinders during compression and explosion strokes and includes the engine lubricating oil particulates.
External air is introduced into the crank case from an upstream side of a throttle valve disposed in the intake passage through the cylinder head cover and scavenging holes formed in the cylinder head and the cylinder block, in order to scavenge the inner space of the crank case and the cylinder head cover. Cylinder head cover serves to seal off the cylinder head space from the outside of the engine. As a result of operation of the internal combustion engine, blow-by gases from the combustion process and oil droplets from the lubricant system of the engine are present inside the cylinder head. These quantities of gases and liquid present in the cylinder head space are usually passed through separating devices and returned to the intake area and/or the oil circuit.

In order to prevent the engine oil particulates from being introduced into the intake passage, oil separating means are provided in the blow-by gas passage formed within the cylinder head cover. To return the blow-by gas, a blow-by gas outlet is formed in the cylinder head cover to a downstream side of the throttle valve disposed in the intake passage. Such separating devices for separating the oil components of the crankcase gas are usually mounted in the immediate vicinity of the cylinder head cover or, ideally, they are integrated into the cylinder head cover.

Conventional cylinder head cover designs comprise baffle plate side by side wall construction wherein the blow-by gases pass through them and the separated oil is collected in multiple drain slots. Effectiveness of oil separation and oil draining are found to be less in such cyclonic separator constructions. In another conventional arrangement, the orifice plate, with or without impactor walls, provides small holes for gases to leave allowing further oil separation.

Such conventional cylinder head cover designs result in improper oil separation from blow-by gases and too much of oil carry over from the cylinder head cover, which results in excess engine oil consumption. Also, contamination of air intake duct occurs. Such a design also requires the presence of a cyclonic separator adding to the complexity of the arrangement, including maintenance related problems.

However, when the amount of blow-by gas increases, there attains a problem in poor separation of oil particulates from the blow-by gas and the blow-by gas including engine lubricant oil particulates is introduced into the engine combustion chambers together with the engine intake air. Further, the separation of engine oil using the conventional baffle arrangement does not sufficiently separate the oil and thus is not suitable to be used in consideration of latest emission regulations.

Moreover, when the engine is running at high speed under heavy load, since pressure difference between the upstream sides and the downstream of the throttle valve decreases, there is a problem in that blow-by gas can flows through the external air passage in the reverse direction to the upstream side of the throttle valve in the intake passage.

Also, mounting an external separator on the head cover increases the size of the engine, thereby making it difficult to design the engine to be compact. Further the conventional baffle arrangement does not cover the exhaust port and prevent the oil mist splashed by the rotating cam of the engine.

Therefore, it is desirable to provide an improved oil separation arrangement which overcome the disadvantages of the conventional oil separation arrangement and providing the filtered blow-by gas by effectively separating the oil particulates from the blowby gases.

OBJECT OF THE INVENTION

The main object of the present invention is to provide an improved cylinder head cover for the cylinder head of an internal combustion engine, eliminating the problems associated with the prior art.
Another object of the present invention is to provide a cylinder head cover, which can effectively separate oil from the blow by gas, and is integrally provided with the cylinder head cover to make the engine more compact.

Another object of the invention is to provide an oil separator arrangement for blowby gas, which enables for simple and cost effective in construction and assembly of engine components.

Another object of the invention is to improve the engine oil separation from blow by gases and eliminate the need for a cyclonic separator for the ventilation system.

Further object of the present invention is to provide an oil separator arrangement, without increasing the size of the cylinder head and cylinder head cover.

SUMMARY OF THE INVENTION

The present invention which achieves the objectives relates to an engine cylinder head cover for an internal combustion engine provided with blow-by gas flowing passages. The cylinder head cover covering the cylinder head of an internal combustion engine includes a baffle plate having plurality of bay walls arranged adjacent and parallel to each other with a predetermined spacing. The baffle plate attached with the cylinder head cover separates oil particulates from the blow by gas. An orifice plate and a striker plate are provided adjacent to the bay walls of the baffler plate for further separation of oil from the blow-by gas. The separated blow by gas from the bay walls continue to pass through the orifice plate and the striker plate for further separation of oil from blow by gas.

The baffle plate and orifice striker plate are formed as an oil separator module inside the cover. The baffle plate bay walls are placed top and bottom to each other paralleled to form alternate inlet and exit bays with a striker and orifice plate at end to have a better oil separation. The oil separator module having baffle plate attached with the cylinder head cover which separates oil from the blowby gas is integrated with the cylinder head cover. The blowby gas along with the oil mist enter through the blowby gas port and pass to the cylinder head cover and hit the baffle plate wall, were the particulate matter will be filtered.

The gas along with oil mist hits the baffle wall when the gas moves top and bottom and thus the oil is collected through the drains which are provided at different interval due to the gravity effect of oil separation. The oil which is collected in the drain slots will get drained after required height achieved in the slot volume. The remaining gas with oil hits the striker plate through the orifice plate where the remaining oil will be drained. The blowby gas which is separated from the engine oil escapes through the vent present in the cylinder head cover. The blowby gases escaped through the vent passes to the oil separator were the remaining oil in the gas is separated and enter into the crankcase. The gas removed is entered to the air intake system.

Engine oil separation from blow-by gases accomplished by this invention leads to elimination of the cyclonic separator from the engine ventilation system since the oil consumption is well under control even without the cyclone separator, Removal of the cyclone separator from the ventilation system results in simpler engine packaging on the vehicle.

BRIEF DESCRIPTION OF THE DRAWINGS

Referring now to the drawings wherein the showings are for the purpose of illustrating a preferred embodiment of the invention only, and not for the purpose of limiting the same.

Fig. 1 shows the sectional view of the cylinder head cover for improved blowby gas ventilation, in accordance to the exemplary embodiment of the present invention.

Fig. 2 shows the baffle plate cover design along with cylinder head cover for improved blowby gas ventilation, in accordance to the present invention.

Fig. 3 shows the cylinder head cover for the improved blowby gas ventilation, in accordance to the present invention.

Fig. 4 shows the arrangement of blowby gas ventilation, in accordance to the present invention.

DETAILED DESCRIPTION

The present invention relates to a cylinder head cover having an integrated oil separator module for separating air and oil from the blow-by gases or crank case gases of an internal combustion engine. The improved arrangement discloses an engine crankcase ventilation system having a cylinder head cover constructed with bay walls and integrated orifice striker for facilitating improved separation of oil particulates from the blow-by gases from the engine.

Fig. 1 and 2 shows the sectional view of the cylinder head cover for improved blowby gas ventilation, in accordance to the exemplary embodiment of the present invention. The cylinder head cover (1) comprises a baffle plate (2) having bay walls (12) formed such that the bay walls (12) are arranged adjacent to each other with predetermined spacing. The bay walls (12) are arranged parallel to each other such that they form alternate inlet and exit bays. The blow-by gases mixed with the oil particulates enters through the blow-by gas entry port (6) and passes through the inlet bays to reach the baffle plate (2). The blow by gasses hit the bay walls (12), were the oil particulate matter will get separated and filtered. A striker plate (3) and an orifice plate (4) are provided adjacent to the bay walls (12) formed of the baffler plate (2) for further separation of oil from the blow-by gas. The separated blow by gas from the bay walls (12) continue to pass through the striker plate (3) and the orifice plate (4) for further separation of oil from blow by gas.

The baffle plate (2) along with the orifice striker plate (3, 4) is formed as an oil separator module inside the cylinder head cover (1). The baffle plate bay walls (12) are placed top and bottom to each other paralleled to form alternate inlet and exit bays with a striker plate (3) and an orifice plate (4) at an end to provide a better oil separation from the blow by gases. A plurality of oil drain slots (5) is formed in the bottom of the blow-by gas passage so as to drain out the oil, which has been separated from the blow-by gas. The number and positions of the oil drain holes (5) can be freely changed according to the shape and characteristics of the engine and the head cover (1).

The blow-by gas produced in the engine will flow upwards through the cylinder head, and enter the blow-by gas entry passage (6), to get separated with the cylinder head cover oil separator module, and then flow to pass through the external oil separator. The oil will get separated from the blow-by gas while the gas is passing through the oil separator module in the cylinder head cover (1) and then passing through the external oil separator. The separated oil is get collected in an oil sump through the oil drain hole in the bottom of the flow path.

Fig. 3 shows the cylinder head cover for the improved blowby gas ventilation, in accordance to the present invention. A blow-by gas passage tube (7) is provided with the cylinder head cover (1) so as to discharge the blow-by gas from the engine. The oil separator module having baffle plate (2) attached with the cylinder head cover (1) separating the oil particulates from the blowby gas is integrated with the cylinder head cover (1).

The blowby gas along with the oil mist enter through the blowby gas entry passage (6) and pass to the cylinder head cover (1) and hit the baffle plate walls (12), were the particulate matter is separated and filtered. The purified gas as well as the separated oil is discharged respectively through the oil drains (5) and the blowby gas passage tube (7).

Fig. 4 shows the arrangement of blowby gas ventilation, in accordance to the present invention. The internal combustion engine includes cylinder head (8) and a crankcase (9) for assembling the engine components and a cylinder head cover (1) for covering the cylinder head (8) of the engine. An external air-oil separator (11) is coupled with the blow-by gas passage tube (7) for further separation of oil from the blow-by gas. An oil sump (10) is present at the bottom of the crankcase (9) so as to accumulate the drained oil, which has been drained and separated from the blow-by gas from the cylinder head cover (1), oil separator module and through the external oil separator (11).

The external oil separator (11) is made up of an assembly to have oil separating units (not shown), such that when the blow-by gas contacts the inside wall of the oil separator (11), the oil particulates and the air get separated and filtered. The number, size, configuration and the type of the oil separator (11) can be freely changed according to various requirements such as the characteristics of the blow-by gas and the shape of the blow-by gas passage.

The blow by gases or the crank housing gases from the engine which enter into the cylinder components will flow through the oil separation entry passages, in which the oil particulates contained in the gas are separated. The separated oil is then collected in the oil sump (10). The purified blow by gases from the external oil separator (11) is passed to the engine intake through the air or gas outlet tubes (13).
The blowby gases separated from the cylinder head cover (1) oil separator module is allowed to escape through the vent and then passed through the external oil separator (11) through the gas passage tube (7), for further separating the remaining oil particulates in the blowby gases. The gas separated or removed from the external separator (11) is made to enter into the intake system of the internal combustion engine.

In operation, the gas along with oil mist hits the baffle wall and moves upward and downward and thus the oil is separated and collected through the drain slots (5) because of gravity effect of oil separation. The oil which is collected in the drain slots (5) will get drained into crankcase oil sump (10). The remaining blowby gas pass through the orifice plate (4) and hit the striker plate (3) for further separation of oil from blowby gas. The separated gas contains minimal amount of oil mist which is escaped through the vent provided at the cylinder head cover (1) and then passes to the oil separator (11) for further separation and filtering of oil from the gas.

The remaining oil from the separator (11) flows to the crankcase oil sump (10). There is a cap (not shown) with opening which covers the drain slots facing cam shaft blocks the engine oil splashes from the cam shaft and thus the oil does not enter the baffle plate (2). The oil separator module integrated with cylinder head cover (1) has blowby gas entry passage (6) through which the blow-by gas can enter and the baffle plates (2) each of which is formed as bay wall. The bay walls on the inside wall of separator module act to twist the flow of the blow-by gas passing there through and thereby increasing the flow rate of the blow-by gas. When the flow rate of the blow-by gas is increased, the oil can be separated to form a pure gas component due to the difference in specific gravity between the oil and the gas components.

Engine oil separation from blow-by gases accomplished by this invention leads to elimination of the cyclonic separator from the engine ventilation system since the oil consumption is well under control even without the cyclone separator, removal of the cyclone separator from the ventilation system results in simpler engine packaging on the vehicle. The baffle plates forming bay walls are arranged such that the subsequent segment projects into the flow path of the previous segment, thus improving the flow characteristics and hit rate for effective separation of oil particulates form the blow by gases.

The oil separator module having baffle plate forming bay walls and the striker plate and the orifice plate are integrated with the cylinder head cover for effective separation of oil particulates from the blow by gases thus forming a compact and effective arrangement for blowby gas oil separation.

The oil separation according to the present invention employs passage of blowby gas in upward and downward flow of the gas which is advantageously carried out in an extremely efficient manner, and thus providing an improved and effective oil separation arrangement for the blowby gases generated in the internal combustion engines.

The foregoing description is a specific embodiment of the present invention. It should be appreciated that this embodiment is described for purpose of illustration only, and that numerous alterations and modifications may be practiced by those skilled in the art without departing from the spirit and scope of the invention. It is intended that all such modifications and alterations be included insofar as they come within the scope of the invention as claimed or the equivalents thereof.

We Claim:

1. A cylinder head cover (1) for an engine, comprises,

a baffle plate (2) having plurality of bay walls (12) arranged adjacent and parallel to each other with a predetermined spacing, wherein the baffle plate (2) attached with the cylinder head cover (1) separates oil particulates from the blow by gas;

an striker plate (3) and an orifice plate (4) are provided adjacent to the bay walls (12) of the baffler plate (2) for further separation of oil from the blow-by gas, wherein the separated blow by gas from the bay walls (12) continue to pass through the striker plate (3) and the orifice plate (4) for further separation of oil from blow by gas.

2. The cylinder head cover as claimed in claim 1, wherein the bay walls (12) are placed in top and bottom manner, and alternate to each other to form alternate inlet and exit bays;

3. The cylinder head cover as claimed in claim 1, wherein a blow-by gas entry passage (6) provided with the baffle plate (2) in the cylinder head cover (1), such that the blow-by gases containing oil particles enters through the blow-by gas passage (6) in the baffle plate (2) and passes to the bay walls (12) through the inlet bays in the baffle plate.

4. The cylinder head cover as claimed in claim 1, wherein drain slots (5) are provided in the baffle plate (2), such that the oil collected in the drain slots (5) is drained to crankcase oil sump (10).

5. The cylinder head cover as claimed in claim 1, wherein the drains slots (5) provided in the baffle plate (2) can have different shape, size and intervals.

6. The cylinder head cover as claimed in claim 1, wherein a cap with an opening is provided for covering the drain slots (5).

7. The cylinder head cover as claimed in claim 1, wherein the blow by gas separated from the oil particles escapes through a vent provided in the cylinder head cover (1).

8. A crankcase ventilation system including the cylinder head cover (1) as claimed in the preceding claims.

9. An engine including the cylinder head cover (1) and a crankcase ventilation system, as claimed in any one of the preceding claims.