Patent Application
20080196369
This application claims priority to the Italian national application entitled VEHICLE ENGINE AIR INTAKE FILTER, having application number BO 2006A 000857, filed on Monday, Dec. 18, 2006.
The present invention relates to a vehicle engine air intake filter.
Flat filters are known comprising an undulated filtering element fixed to a peripheral frame to impart mechanical strength to the filtering element.
In one embodiment, the peripheral frame is normally made of plastic (e.g. polyurethane) material molded onto the filtering element so as to incorporate a peripheral portion of the filtering element. This embodiment is only suitable for filters housed, in use, inside a closed casing and not subjected to direct mechanical stress, one example of which is illustrated, for example, in Patent Application IT2004BO00156.
In another embodiment, the peripheral frame comprises a number of shaped metal members welded or screwed to one another. This embodiment is normally used when the filter is fixed by screws or similar in front of a vehicle air intake. Currently marketed filters of this type, however, are heavy and complicated to produce, and therefore unsuitable for aircraft applications and particularly helicopter air intakes.
It is an object of the present invention to provide a vehicle engine air intake filter designed to eliminate the above drawbacks, and which at the same time is cheap and easy to produce.
According to the present invention, there is provided a vehicle engine air intake filter as claimed in the attached Claims.
A non-limiting embodiment of the present invention will be described by way of example with reference to the accompanying drawings, in which:
Number 1 in
As shown in
The peripheral edge of filtering element 2 is secured inside annular seat 4 by a layer 5 of glue completely filling annular seat 4. By way of example, the glue used to secure the peripheral edge of filtering element 2 inside annular seat 4 may be polyurethane, silicone, epoxy glue or similar.
Filtering element 2 is preferably defined by an undulated filtering component covered on both sides with aluminium retaining nets (not shown in detail) for maintaining the shape of the undulated filtering component (alternatively, the retaining nets may be made of stainless steel or composite material). The filtering component is made of cloth (e.g. cotton or synthetic material or even other non-inflammable material) soaked in oil and folded to form, for example, four superimposed layers. The filtering component cloth may, of course, form a different number of layers, and need not necessarily be soaked in oil. In the embodiment shown, filtering element 2 has a transverse thickness of 34 mm, and 8 mm spacing between adjacent undulations.
Peripheral frame 3 is formed by joining a flat top annular border 6, made from a single sheet of material, and an S-shaped bottom annular border 7, also made from a single sheet of material. In a preferred embodiment, the two borders 6, 7 of peripheral frame 3 are made from sheets of composite material and are glued together. The sheets of the two borders 6, 7 of peripheral frame 3 are typically made of carbon fibre, and are each 2 mm thick.
In a preferred embodiment, a reinforcing net 8 is interposed between filtering element 2 and bottom annular border 7 of peripheral frame 3, rests on bottom annular border 7, and provides for reinforcing undulated filtering element 2 to withstand the air intake pressure without deforming. The function of reinforcing net 8 is particularly important in the case of large-area filters 1.
Reinforcing net 8 is normally made of metal, preferably 1 mm diameter stainless steel, wire, and, in the embodiment shown, has a mesh size of 25 mm2 in the form of a 5×5 mm square.
Peripheral frame 3 has an outer edge 9 projecting outwards of annular seat 4 and having a number of through holes 10 for screws by which to assemble filter 1.
In the embodiment shown, peripheral frame 3 is flat. In a different embodiment shown in
Filter 1 as described above has numerous advantages. In particular, it is cheap and easy to produce, and, above all, despite its structural rigidity and mechanical strength, is much lighter than similar marketed filters. Moreover, filter 1 as described above allows the use of large-area filtering elements 2, and is therefore particularly suitable for aircraft applications, and particularly for helicopter air intakes.
| Number | Date | Country | Kind |
|---|---|---|---|
| BO2006A 000857 | Dec 2006 | IT | national |
