Oil capturing device having a rotary component

An oil capturing device for capturing oil from crankcase gases. The oil capturing device includes a housing containing a central chamber and a rotor disposed in the central chamber. The rotor includes a shaft rotatable about an axis and a flange extending from the shaft towards the inner wall of the central chamber. The flange is in contact with the inner wall, and spirals along the shaft so as to define a gas passage interconnecting the inlet to the first port. The gas passage provides a passage for crankcase gases to flow from the inlet to the first port, and narrows as it proceeds from the inlet to the port so as to compress crankcase gases travelling from the inlet to the first port. The rotor may be operable by a motor, pulley connected to the engine, or a turbine driven by the engine's exhaust.

FIELD OF THE INVENTION

The invention relates to an oil separating device for separating oil from engine gases. More particularly, the invention relates to an oil separating device including a rotor having a shaft a flange spiraling along the shaft so as to define a gas passage. The gas passage narrows so as to compress the crankcase gases and facilitate the capture of oil.

BACKGROUND OF THE INVENTION

An internal combustion engine includes a combustion chamber, where a fuel air mixture is burned to cause movement of a set of reciprocating pistons, and a crankcase, which contains the crankshaft driven by the pistons. During operation, it is normal for the engine to experience “blow-by,” wherein combusted engine gases leak past the piston-cylinder gap from the combustion chamber and into the crankcase. These blow-by or crankcase gases contain moisture, acids and other undesired by-products of the combustion process.

It is normal for crankcase gases to also include a very fine oil mist. The oil mist escapes from the engine to the manifold. The oil mist is then carried from the manifold back into the combustion chamber along with the fuel/air mixture. This results in an increase in oil consumption. Additionally the combustion of the oil mist causes a build-up of residuals in the combustion chamber and on pistons which over time decreases engine efficiency. An engine typically includes a Positive Crankcase Ventilation (PCV) system for removing these harmful gases from the engine and prevents those gases from being expelled into the atmosphere. It is known to incorporate an oil separating device in a PCV system to remove oil from these crankcase gases. It is known to use manifold vacuum to draw crankcase gases into localized high velocity areas of the oil separator to promote separation of oil from the gases. The oil is re-introduced back to a sump via a drain device which is located generally at the bottom of the oil separator to allow for gravity to assist the drainage of oil. The sump generally holds excess oil in the system.

However, during certain engine operating conditions such as when the engine is operating at a wide open throttle, there is not enough manifold vacuum to draw the crankcase gases. Accordingly some oil separating devices use auxiliary power to draw the crankcase gases. For instance, some oil separating devices use a centrifugal oil separator to draw crankcases gases and separate the oil from those gases. Such devices use a rotary component driven by a motor or a turbo transmission. However the such centrifugal oil separators do not capture oil, rather oil is separated from the crankcase gases and collected. Yet other oil separating devices with a rotary component include a shaft and a spiraling member spiraling along the shaft. The spiraling component defines a uniformly shaped passage interconnecting the inlet to an outlet. The cyclone effect created by these devices thrusts the crankcase gases against a wall whereby the oil is separated oil from crankcase gases. Such devices do not compress the crankcase gases, rather the separated oil is splattered against and collects on the inner wall of the housing and drains to the engine.

However, micron and sub-micron particles of oil remain in the crankcase gases. Accordingly, it remains desirable to provide an improved device that is more efficient than conventional oil separator designs in capturing micron and sub-micron particles of oil from crankcase gases while at the eliminating reliance upon manifold vacuum to draw crankcases gases.

SUMMARY OF THE INVENTION

According to one aspect of the invention, an oil capturing device is provided for capturing oil from crankcase gases. The oil capturing device includes a housing containing a central chamber. The central chamber includes an inner wall, a first port interconnecting the central chamber to the housing, and a rotor. The rotor includes a shaft rotatable about an axis and a flange extending from the shaft towards the inner wall of the central chamber. The flange includes a distal edge in contact with the inner wall. The flange spirals along the shaft so as to define a gas passage interconnecting the inlet to the first port. The gas passage provides a passage for crankcase gases to flow from the inlet to the first port, and the gas passage narrows as it proceeds from the inlet to the port so as to compress crankcase gases as these gases travel from the inlet to the first port. The compressed gas is drawn through the first port where oil is captured from the compressed gas, and wherein the captured oil drains into an oil drain and the filtered crankcase gases are drawn an outlet. Crankcase gases are drawn through the central chamber by having the rotor spin. The rotor may be operable by a motor, pulley connected to the engine, or a turbine driven by the engine's exhaust.

DETAILED DESCRIPTION OF THE INVENTION

Referring to the Figures, wherein like numerals indicate corresponding parts throughout the several views, an oil capturing device10for capturing oil from crankcase gases is provided. With reference toFIGS. 1-3, the oil capturing device10includes a housing12containing a central chamber14. The central chamber14has an inner wall16and includes an inlet18interconnecting the engine with the central chamber14. The inlet18provides a passage for crankcase gases to be drawn into the central chamber14. A first port20interconnects the central chamber14to the housing12. The housing12further includes an oil drain22interconnecting the housing12with the engine, and an outlet24interconnecting the housing12with the engine intake.

With reference now toFIGS. 1-5, a rotor26is disposed in the central chamber14between the inlet18and the first port20. The rotor26includes a shaft28rotatable about an axis30and a flange32extending from the shaft28towards the inner wall16of the central chamber14. The flange32includes a distal edge34wherein at least a portion of the distal edge34is in contact with the inner wall16of the central chamber14. The flange32spirals along the shaft28so as to define a gas passage36interconnecting the inlet18to the first port20. Specifically, the gas passage36is defined by the space between the shaft28, flange32, and inner wall16. The gas passage36provides a passage for crankcase gases to flow from the inlet18to the first port20. The shaft28includes a first end portion38opposite a second end portion40. The first end portion38is adjacent to the inlet18and a second end portion40adjacent to the first port20. The gas passage36narrows as it proceeds from the first end portion38to the second end portion40so as to compress crankcase gases as it travels from the inlet18to the first port20. The compressed gas is drawn through the first port20and into a punching and impact plate42, where oil is captured from the compressed crankcase gas. The captured oil then drains into the oil drain22and the filtered crankcase gases are drawn into the outlet24.

As stated above, the gas passage36is defined by the space between the shaft28, flange32and the inner wall16of the central chamber14as indicated by the hollowed arrow inFIG. 2. The flange32further includes an upper surface44spaced apart and opposite a lower surface46. The distal edge34interconnects the upper surface44to the lower surface46, and as the flange32spirals from the inlet18to the outlet24. The upper surface44faces the lower surface46so as to define the gas passage36, and the distance between an upper surface44and a facing lower surface46decreases as the flange32proceeds from the inlet18to the first port20. Thus, the gas passage36narrows and the crankcase gases are compressed by the time the gases reach the first port20. It is anticipated that the pitch of the flange32may be adjusted so as to deliver a desired amount of crankcase gases or affect the compression rate and pressure of those gases. For instance, the flange32may spiral around the shaft28only two times, thus decreasing the pressure of the compressed crankcase gas.

With reference again toFIG. 2, the gas passage36is also narrowed by having the shaft28widen as the shaft28proceeds from the inlet18to the first port20. Specifically, the first end portion38of the shaft28has a first peripheral edge48and the second end portion40has a second peripheral edge50larger than the first peripheral edge48. Thus as the shaft28widens, the gas passage36narrows. It is anticipated that other configurations may be used to narrow the gas passage36, and the illustrations presented herein are not limiting.

With reference again toFIGS. 2 and 3, a first preferred embodiment of oil capturing device10is provided. Specifically, the housing12further includes a mid-chamber52partially enclosing the central chamber14and an outer chamber54partially enclosing the mid-chamber52. The oil drain22is disposed on the mid-chamber52, and the first port20interconnects the central chamber14with the mid-chamber52. A second port56interconnects the mid-chamber52to the outer chamber54, and the outlet24interconnects the outer chamber54with the engine intake. The first port20is disposed above the second port56so as to promote the drainage of captured oil into the oil drain22and the flow of filtered crankcase gases into the outlet24. The oil drain22is disposed above and in communication with the engine sump (not shown) so as to allow captured oil to drain back into the engine and be recycled. The outlet24is in communication with the engine manifold (not shown) so as to provide for recirculation of the crankcase gases.

It is anticipated that the rotor26may be spun by a motor58, pulley60, or turbine62. With reference now toFIG. 7a motor58is attached to the rotor26. The motor58may be connected to the vehicle's battery (not shown) and may be controlled by a sensor59(not shown) that detects the vacuum pressure in the engine's intake. Thus, when the sensor59detects that the vacuum pressure falls below a predetermined amount the sensor59actuates the motor58so as to cause the rotor26to spin. The spinning of the rotor26in turn causes the crankcase gases to be drawn from the engine, and draws the crankcase gases along the gas passage36, whereby the crankcase gases are compressed and then captured as described above. Preferably the motor58may spin the rotor26at RPM (revolutions per minute). It is anticipated that the speed of the motor58may continuously varied so as to maintain a steady pressure level across the oil capturing device10. Thus, as the vacuum pressure varies in the intake or across the oil capturing device10, the motor58speed may also vary. Such motors58and sensors are known. For instance, the rotor26may be driven by a brushless servo motor and a static pressure transducer type sensor may be used to control the motor58and monitor the vacuum pressure in the vehicle manifold.

With reference now toFIG. 8a pulley60is attached to the rotor26. Specifically, the rotor26includes a pin59and the pulley60is mounted to the pin59so as to rotate the pin59thereby rotating the rotor26. The pulley60is driven by the engine and is operable to rotate the rotor26. The pulley60may be engaged and disengaged from the engine by a configuration of gears (not shown). Furthermore, the RPM of the rotor26may be controlled by changing the pulley ratio. Thus, like the motor58, the pulley60may be adjusted so as to maintain a steady pressure level across the oil separating device.

With reference now toFIG. 6a turbine assembly64fixedly connected to rotor26so as to spin the rotor26. The turbine assembly64includes a turbine housing66having a housing inlet68that interconnects the turbine assembly64to the vehicle's exhaust system. The turbine assembly64further includes a turbine blade70rotatably housed within the turbine housing66. Exhaust is used to turn the turbine blade70and thus rotate the rotor26. Thus crankcase gases are always drawn from the engine so long as the engine is operating.