TECHNICAL FIELD

The present application relates to rotating filter elements.

BACKGROUND

During operation of an internal combustion engine, a fraction of combustion gases can flow out of the combustion cylinder and into the crankcase of the engine. These gases are often called “blowby” gases. The blowby gases include a mixture of aerosols, oils, and air. If vented directly to the ambient, the blowby gases can harm the environment. Accordingly, the blowby gases are typically routed out of the crankcase via a crankcase ventilation system. The crankcase ventilation system may pass the blowby gases through a coalescer (i.e., a coalescing filter element) to remove a majority of the aerosols and oils contained in the blowby gases. The coalescer includes filter media. The filtered blowby gases are then either vented to the ambient (in open crankcase ventilation systems) or routed back to the air intake for the internal combustion engine for further combustion (in closed crankcase ventilation systems).

Some crankcase ventilation systems utilize rotating coalescers that increase the filter efficiency of the coalescing filter elements by rotating the filter media during filtering. In rotating filter cartridges, the contaminants (e.g., oil droplets suspended and transported by blowby gases) are separated inside the filter media of the filter cartridge through the particle capture mechanisms of inertial impaction, interception, diffusion, and gravitational forces onto the fibers. By rotating the filter media, inertial impaction and gravitational forces are enhanced by the additional centrifugal force. Additionally, the rotation of the filter cartridge can create a pumping effect, which reduces the pressure drop through the filtration system. Rotating filter cartridges may include fibrous filters as well as centrifugal separation devices.

The rotating filter elements need to be periodically serviced and replaced. Accordingly, the rotating filter elements need to be removably attached and retained on a drive shaft. When the filter element is installed on the drive shaft, the drive shaft imparts rotation on the filter element during filtering operations. When the filter element is removed from the drive shaft, it can be serviced and reinstalled onto the drive shaft, or a new filter element can be installed onto the drive shaft.

SUMMARY

One example embodiments relate to a filtration system. The filtration system includes a housing having an inlet and an outlet. The filtration system includes a drive mechanism including a drive shaft with a flat section. The filtration system further includes a rotating filter element that is positioned within the housing and in fluid communication with the inlet and the outlet. The rotating filter element is configured to separate a suspended liquid from a fluid received through the inlet. The rotating filter element includes a first endplate, a second endplate, and filter media positioned between the first endplate and the second endplate. The rotating filter element further includes a filter element sleeve or bushing configured to receive the drive shaft. The filter element sleeve or bushing has a projection that projects radially inward. The projection interacts with the flat section of the rotating shaft so as to transfer rotation from the rotating shaft to the rotating filter element.

Another example embodiment relates to a rotating filter element. The rotating filter element includes a first endplate, a second endplate, and filter media positioned between the first endplate and the second endplate. The rotating filter element further includes a filter element sleeve or bushing configured to receive a drive shaft of a filtration system when the rotating filter element is installed in the filtration system. The filter element sleeve or bushing includes a projection that projects radially inward. The projection interacts with a rotating shaft of the filtration system so as to transfer rotation from the rotating shaft to the rotating filter element. The rotating filter element is configured to separate a suspended liquid from a fluid.

These and other features, together with the organization and manner of operation thereof, will become apparent from the following detailed description when taken in conjunction with the accompanying drawings, wherein like elements have like numerals throughout the several drawings described below.

