Patent Application
20200291836
The subject invention is directed to an oil filter cover, and more particularly, to a removable cover for an oil filter housing of an Integrated Drive Generator (IDG) coupled to a gas turbine engine.
Aircraft currently rely upon electrical, pneumatic and hydraulic systems for secondary power generation. A typical electrical system in an aircraft utilizes an IDG coupled to a gas turbine engine to provide fixed frequency power to the power distribution system and to a variety of loads.
An exemplary IDG includes a generator, a hydraulic unit and a differential assembly arranged in a common housing. The differential assembly is coupled to a gas turbine engine by way of an input shaft. The rotational speed of the input shaft varies during the operation of the gas turbine engine. The hydraulic unit cooperates with the differential assembly to provide a constant speed to the generator throughout the operating range of the engine.
IDGs operate at elevated temperatures. Synthetic oils are used for cooling and lubrication in IDGs, and as a working fluid. In these systems, tiny metallic wear particulates are formed from normal operation. These wear particles are carried by the oil within an oil circuit, and must be removed to maintain the working efficiency and life of the system.
For this reason, the oil circuit includes an oil filter located in a housing having an external cover that facilitates installation, removal and periodic replacement of the oil filter. It is desirable to design oil filters to optimize the dirt holding capacity and operational life of the filter. This is typically done by increasing the amount of filter media within the fixed dimensions of the filter cartridge, since the housing that supports the cartridge has dimensions that are immutable due to spatial constraints, especially in the case of an IDG coupled to a gas turbine engine on an aircraft.
However, as the amount of filter media within the cartridge is reduced, the pressure drop through the filter cartridge also increases, impacting the efficiency of the system. It would be beneficial therefore, to maximize the amount of filter media in the oil filter without increasing the pressure drop through the filter cartridge. The subject invention provides a solution by way of a uniquely configured cover for the oil filter housing, which is designed to accommodate a filter cartridge that has a greater axial length than the filter housing within which it is accommodated, while remaining within the spatial constraints that permit ready access to and removal of the cover and filter from the housing for routine maintenance purposes.
The subject invention is directed to a new and useful cover for an oil filter housing for use with an Integrated Drive Generator (IDG) coupled to a gas turbine engine. The cover includes an elongated body defining an upper end portion and a lower end portion, and it has a central axis extending therethrough, which delineates an axial length of the body. An axial bore extends through the body of the cover from the lower end portion thereof to an interior end wall in the upper end portion thereof for accommodating an axial end portion of an oil filter located within the housing.
In accordance with a preferred embodiment of the subject invention, the axial bore of the body has an axial length that is greater than 85% of the axial length of the body.
More preferably, the axial length of the bore is about 90% to about 94% of the axial length of the body. In an exemplary embodiment of the cover, the axial length of the bore is about 1.57 inches to about 1.58 inches, and the axial length of the body is about 1.67 inches to about 1.70 inches.
Furthermore, the axial bore has a diameter of about 1.81 inches, and the body is formed from 2024 aluminum alloy and the upper end portion of the body has a hexagonal engagement surface formed thereon for installing the cover on the housing and for removing the cover from the housing.
These and other features of the filter housing cover of the subject invention will become more readily apparent to those having ordinary skill in the art to which the subject invention appertains from the detailed description of the preferred embodiments taken in conjunction with the following brief description of the drawings.
So that those having ordinary skill in the art will readily understand how to make and use the subject invention without undue experimentation, preferred embodiments thereof will be described in detail herein below with reference to the figures wherein:
Referring now to the drawings wherein like reference numerals identify similar structural features, there is illustrated in
Referring to
The central longitudinal axis LAxis of the body 20 delineates an axial length (LBody) of the body 20. More particularly, as shown in
The lower end portion 24 of the body 20 of cover 14 has a helical thread formation with a standard pitch for threadably engaging the housing 18, as best seen in
Referring to
In accordance with a preferred embodiment of the subject invention, the axial length LBore of the bore 30 of body 20 is greater than 85% of the axial length LBody of the body 20. More preferably, the axial length LBore of the bore 30 of body 20 is about 90% to about 94% of the axial length LBody of the body 20. In sum, in an exemplary embodiment of the cover 14, the axial length LBore of the bore 30 of body 20 is about 1.56 inches to about 1.59 inches, and the axial length LBody of the body 20 is about 1.69 inches to about 1.72 inches.
Referring now to
While the subject disclosure has been shown and described with reference to preferred embodiments, those skilled in the art will readily appreciate that changes and/or modifications may be made thereto without departing from the scope of the subject disclosure.
