JP2010511827A - Engine head cover assembly with integral oil separator - Google Patents

Abstract

  A head cover assembly for covering a crankcase of an internal combustion engine includes a head cover and an integral oil separator. The oil separator includes a housing that forms a flow path that separates oil from crankcase gas passing through the flow path. At least a part of the housing is integrally formed along the inner surface of the head cover.

Description

(Refer to related patents)
This application claims priority to US Provisional Patent Application No. 11 / 565,872, filed Dec. 1, 2006, the entire contents of which are incorporated by reference into this application.
The present invention relates to an engine head cover for an internal combustion engine. In particular, the present invention relates to an engine head cover having an integral oil separator for separating oil from crankcase gas during engine operation.

  Internal combustion engines generally have a combustion chamber (where a mixture of fuel and air is combusted to move a set of reciprocating pistons) and a crankcase (which contains a crankshaft driven by the piston). Including. During operation, the engine normally produces a “blow-by” (gas leak from the combustion chamber to the crankcase). In blow-by, combustion gas leaks from the combustion chamber through the piston-cylinder gap into the crankcase. Such blow-by or crankcase gases contain moisture, acidic substances and other undesirable by-products of the combustion process.

  Engines typically include a crankcase ventilator (PCV) for removing harmful gases from the engine to prevent the harmful gases from being discharged into the atmosphere. PVC prevents the exhaust of gas to the atmosphere by using a manifold vacuum to draw steam from the crankcase into the intake manifold. The steam is then carried along with the fuel / air mixture to the combustion chamber intake manifold where it is burned. In general, the flow or circulation in the device is controlled by a PCV valve. The PCV valve acts as a crankcase ventilation device as well as a pollution control device.

  Crankcase gas usually also contains very fine oil mist. Oil mist is carried to the manifold by PCV. The oil mist is then burned together with the fuel / air mixture in the combustion chamber. As a result, the oil consumption increases. A known method for removing oil from crankcase gas is to use an oil separator. Crankcase gas flows through the oil separator. A local high pressure area in the oil separator facilitates the separation of oil from the gas. The oil is returned to the sump via the drainage device. Oil sumps generally store excess oil in the equipment.

  It remains desirable to provide an improved oil separator that is more efficient than conventional oil separator designs for removing oil from crankcase gas. Further, in order to reduce the package space occupied by the oil separator in the engine, it is still desired to provide an oil separator that is compact in size and integrated with a part of the engine housing such as a head cover.

  According to one aspect of the invention, a head cover assembly for covering a crankcase of an internal combustion engine is provided. The head cover assembly includes a head cover and an oil separator. The head cover has a back-to-back outer surface and an inner surface. The oil separator separates oil from the crankcase gas passing through it. The oil separator has a housing disposed along the inner surface of the head cover. The housing has at least one side wall integral with the head cover. The side wall forms an internal space of the oil separator together with the head cover.

  The advantages of the present invention will be readily appreciated as the present invention may be better understood by reference to the following description when considered in conjunction with the accompanying drawings.

1 is a bottom view of a head cover assembly having an integral oil separator according to one embodiment of the present invention. FIG. FIG. 2 is an enlarged bottom view of a part of the head cover assembly shown in FIG. 1. FIG. 2 is an exploded bottom perspective view of the head cover assembly of FIG. 1. It is a bottom view of the head cover assembly by 2nd embodiment of this invention. FIG. 5 is an enlarged bottom view of a part of the head cover assembly shown in FIG. 4. FIG. 5 is a top perspective view of the head cover assembly of FIG. 4. FIG. 5 is an enlarged exploded top perspective view of a portion of the head cover assembly of FIG. 4. FIG. 6 is an enlarged exploded perspective view of a part of a head cover assembly according to a third embodiment of the present invention. FIG. 9 is an enlarged perspective view of a portion of the head cover assembly of FIG. 8, showing the side of the separator cap having tabs for securing the oil separator cap to the head cover. FIG. 9 is a cross-sectional view of the head cover assembly of FIG. 8 illustrating a groove for lockingly receiving a tab for securing the cap to the head cover.

  1-3, the entire head cover assembly for surrounding the crankcase of the internal combustion engine is shown at 10. The head cover assembly 10 includes a head cover 12 having a back-to-back outer surface 14 and an inner surface 16. The head cover assembly 10 also includes an oil separator 20 for removing oil from crankcase gas in the engine. The oil separator 20 includes a housing 30 disposed along the inner surface 16 of the head cover 12. The housing 30 has a plurality of side walls 22, 24, 26 and 28 formed integrally with the head cover 12. At least one of the side walls 28 extends along the inner surface 16 of the head cover 12, and the remaining side walls 22, 24, 26 extend outward from the inner surface 16 of the head cover 12. Alternatively, all side walls of the housing extend outward from the inner surface of the head cover. The head cover can be formed from steel, aluminum or any material or combination of materials known to those skilled in the art. This material is suitable for use in the heat and environment associated with the engine and allows the oil separator housing to be formed integrally with the head cover.

  A portion of the head cover 12 extends between the side walls 22, 24, 26, and 28 to form an internal space. The plate 40 cooperates with the side walls 22, 24, 26, 28 to surround the internal space of the oil separator 20. The head cover 12 has at least one screw hole 29 for fixing the plate 40 to the side walls 22, 24, 26, 28 using bolts. In order to prevent gas from leaking from the internal space of the housing 30, a gasket (not shown) can be disposed between the side walls 22, 24, 26, 28 and the plate 40. Alternatively, the housing can have a generally cylindrical side wall extending from the inner surface of the head cover instead of the straight side wall of the illustrated embodiment. In this case, the plate will have a substantially circular shape in order to cooperate with the substantially cylindrical side wall.

  The housing 30 of the oil separator 20 includes an inlet and an outlet. A plurality of guide walls 43 extend from the head cover 12 toward the plate 40 to form a path 39. The path directs crankcase gas through the housing 30. The path 39 is provided with a shape to facilitate oil separation from the crankcase gas as the crankcase gas flows through the path 39 from the inlet to the outlet. The separated oil is collected in the housing 30 and re-directed to a sump (not shown) for reuse in the engine.

  A second embodiment of the head cover assembly 110 is shown in FIGS. In these figures, similar parts are indicated by numbers plus 100. In this embodiment, the housing 130 is formed by the cap 41, the cover plate 45 and the cylindrical side wall 50. These gather together to form the internal space of the oil separator 120. In particular, the cylindrical side wall 50 is integrally formed with the head cover 112 to form a recess for receiving the cap therein. In particular, the cap 41 includes an annular portion 40 having a thread 42 for engaging a corresponding thread 44 on the head cover 112.

  During assembly, the cap 41 is inserted into the recess formed by the cylindrical side wall 50. Next, in order to thread-engage between the thread 42 of the cap 41 and the corresponding thread 44 formed on the cylindrical side wall, thereby fixing the cap 41 to the head cover 112, the cap 41 is moved to its longitudinal axis. Rotate around. The cap 41 is completely inserted when it comes into contact with the positioning surface 52 formed on the head cover 112 adjacent to the lower end of the cylindrical side wall 50. The cover plate 45 is disposed between the cap 41 and the head cover 112. A plurality of guide walls 143 extend from the cover plate 45 to form a passage for crankcase gas passing through the oil separator 120.

  A third embodiment of the head cover assembly is shown in FIGS. In this embodiment, the thread of the second embodiment is replaced with tab and groove engagement. The tab 60 extends outward from the annular portion 240 of the cap 241, and the guide groove 62 is formed in the cylindrical side wall 250. The guide groove 62 extends substantially longitudinally along the cylindrical side wall 250. A key groove 68 extends from one end 66 of the guide groove 62 in a substantially perpendicular direction. During assembly, the cap 241 of the housing 230 is inserted into the recess formed by the cylindrical side wall 250. The tab 60 slides in the guide groove 62 toward the key groove 68. When the cap 241 contacts the positioning surface 252 at the bottom of the recess, the cap is completely inserted. Next, the cap 241 is rotated so that the oil separator 220 is fixed to the head cover 212 by the tab 60 sliding into the keyway 68. Alternatively, the tab and groove engagement can be reversed. In this case, the tab extends from the head cover, and the groove is formed in the cap.

  In the illustrated embodiment, the guide walls are arranged in a labyrinth to facilitate oil separation from the crankcase gas as the gas flows along the labyrinth. Alternatively, the oil separator can be a cyclone type oil separator. In this case, the guide wall is a coil that forms a spiral flow path extending from the inlet to the outlet of the housing. Those skilled in the art will appreciate that other types of oil separators can be accommodated within the housing. Alternatively, the oil separator can incorporate multiple types of oil separation arrays, such as a combination of labyrinth and cyclone oil separation arrays.

  The present invention has been described in an illustrative manner. Accordingly, the terminology used is intended to be descriptive in nature rather than limiting. Various modifications and variations of the present invention are possible in light of the above teachings. It is therefore evident that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described.

Claims (14)

A head cover assembly for covering a crankcase of an internal combustion engine,
The head cover assembly is
A head cover having back-to-back outer and inner surfaces;
An oil separator for separating oil from crankcase gas passing through the oil separator,
The oil separator has a housing disposed along an inner surface of the head cover, the housing has at least one side wall integral with the head cover, and the side wall together with the head cover has an internal space of the oil separator. Forming a head cover assembly.   2. The head cover assembly according to claim 1, wherein the housing is formed by a plurality of side walls, and one of the side walls extends along the inner surface of the head cover.   The head cover assembly according to claim 2, comprising a plate removably attached to the side wall to enclose the internal space of the oil separator.   The oil separator includes a plurality of guide walls, and the guide walls are integral with the head cover and extend between the inner surface and the plate to form a labyrinth path through which the labyrinth path passes. 4. The head cover assembly according to claim 3, wherein the separation of oil from crankcase gas is caused.   The head cover assembly according to claim 1, wherein the at least one side wall is formed in a cylindrical shape and forms a cylindrical recess in the head cover.   The head cover assembly of claim 5, comprising a cap that can be removably attached to the at least one sidewall to form the interior space of the oil separator.   The head cover assembly according to claim 6, wherein the cap includes threads for engaging corresponding threads on the at least one sidewall surface.   The head cover assembly according to claim 7, further comprising a cover plate disposed between the cap and the head cover so as to surround an internal space of the oil separator.   9. The head cover assembly of claim 8, including a guide wall that extends from the cover plate toward the cap and forms an oil path that separates oil from crankcase gas passing through the oil path.   The cap and the at least one side wall are coupled to each other by an array of tabs and grooves, and the cap is rotated relative to the at least one side wall to lock the tab and the keyway. The head cover assembly according to claim 6, wherein:   The head cover assembly according to claim 10, wherein the tab extends outward from the cap and the keyway is formed in the at least one sidewall.   12. The head cover assembly of claim 11, wherein the at least one sidewall is substantially cylindrical and forms a recess therein for receiving the cap.   13. The head cover assembly of claim 12, wherein the at least one sidewall includes a guide groove, and the guide groove receives the tab of the cap when the cap is inserted into the recess.   14. The key groove extends at a right angle from one end of the guide groove so that a lock engagement is generated between the tab and the key groove by rotation of the cap in the recess. Head cover assembly.

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