Abstract:
In order to facilitate removal of an air filter from a housing, the air filter has a flexible tab which provides a finger grip. In a preferred embodiment, the flexible tab is disposed between a molded gasket and an expanded metal screen which covers the downstream area or dirty side of a pleated filter media.

Description:
FIELD OF THE INVENTION 
     The present invention is directed to a filter element with an integral lift tab. More particularly, the present invention is directed to filter elements which are periodically replaceable and include lift tabs. 
     BACKGROUND OF THE INVENTION 
     As automotive design evolves, there is constant effort to reduce weight and to make engine and drive train components smaller and more compact in order to conserve space. Generally, space allotments in vehicle design favor increasing space in a vehicle&#39;s cabin while reducing space in the engine compartment. As space in the engine compartment becomes smaller, it becomes more and more difficult to service a vehicle&#39;s engine. It is therefore desirable to maintain or even increase access to engine components wherever possible, even as an engine&#39;s space allotment decreases. 
     In order to ensure fuel efficient operation of vehicles and to minimize polluting emissions it is necessary to periodically examine and replace air filters. As an engine compartment&#39;s space decreases, it becomes more and more difficult to conveniently position and mount an air filter for inspection since in order to inspect an air filter, it is necessary to open a housing containing the air filter to observe the dirty side of the air filter. If an air filter is not positioned with its dirty side facing upwardly, then observing the condition of an air filter becomes difficult. Accordingly, there may be a tendency for mechanics to simply avoid examining air filters with the inevitable consequence that vehicles not having proper air filter maintenance not a will have lower fuel efficiency and contribute emissions to pollution. While this, of course, is difficulty if there are only a few vehicles not properly maintained, however when thousands of vehicles are not properly maintained, general fuel consumption increases and air quality is adversely affected. 
     Not only is it necessary to observe an air filter, but in order to completely inspect an air filter it is necessary to remove the air filter from its housing. The paucity of space can make removing an air filter difficult because the air filter is mounted against a seat within an air intake housing and may have become slightly adhered in place. Since in many rapid maintenance situations the customer waits while his or her car is serviced, the mechanic frequently removes the air filter and takes it and shows it to the customer. If the air filter resists removal, then the mechanic is more than likely to simply leave it in place and tell the customer that it is not clogged, when in fact it may well be clogged. Thus, there is a need to have air filters which are readily removable from their housings. 
     While engine air filters are of immediate and specific interest with respect to easy removal and replacement, the same considerations are of interest with respect to other types of air filters, or liquid filters for that matter. 
     SUMMARY OF THE INVENTION 
     It is a feature of the present invention to provide a new and improved filter element wherein the filter element is configured for convenient removal from a housing. 
     In view of this feature and other features, the present invention is directed to a filter element for filtering a fluid flowing therethrough wherein the filter element comprises a filter media having an upstream face facing the fluid to be filtered, and a downstream face. A peripheral gasket is disposed around the filter media for mounting the filter media in a seat. A pull tab is disposed between the peripheral gasket and the filter media and extends out of the gasket to provide an arrangement for facilitating the removal of the filter element from the seat. 
     In a further aspect, the filter element is comprised of a pleated filter media with a gasket that seals between the pleats adjacent the downstream face of the filter media and in still a further aspect, the tab projects across the downstream face of the filter media. 
     In an additional aspect of the invention, the filter element is an air filter used for filtering combustion air for an internal combustion engine and seats within a filter housing in the air inlet of the engine. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a schematic illustration showing the filter element of the present invention installed in a housing of an air intake of an internal combustion engine; 
     FIG. 2 is a perspective view, showing the housing opened so that the downstream side of the filter element is exposed; 
     FIG. 3 is a view similar to FIG. 2 showing the filter element being removed from the housing; 
     FIG. 4 is a planar view of the clean side or downstream of the filter element; 
     FIG. 5 is an end view of the filter element of FIG. 4 partially in section; 
     FIG. 6 is a side view of the filter element of FIGS. 4 and 5; and 
     FIG. 7 is a planar view of the upstream dirty or upstream side of the filter element of FIGS.  4 - 7 . 
    
    
     DETAILED DESCRIPTION 
     Referring now to FIG. 1, there is shown schematically a system  10  for supplying a stream of combustion air  11  to an internal combustion engine  12 . The system  10  includes an inlet  13 , a separable housing  14  and a connection  15  to the engine  12 . Disposed within the separable housing  14  is a filter element  20 , configured in accordance with the principles of the present invention. The filter element  20  includes a pleated filter media  22 , which has an upstream area  23  and a downstream area  24 . Disposed around the periphery  25  of the filter media  22  is a peripheral gasket  26  that is disposed between seats  27  and  28  of the separable housing  14 . The seat  27  is an upstream seat while the seat  28  is a downstream seat. In order to inspect or exchange the filter the separable housing  14  opens along line  29 — 29 . 
     Referring now to FIGS. 2 and 3, a specific example of the housing  14  is shown wherein the housing includes an upstream shell  32  which is hinged to a downstream shell  34 . When the housing  14  is opened, the filter element  20  remains seated on the upstream seat  27  of the upstream shell  32 . As is evident from FIG. 2, removing the filter element from the upstream shell  32  in order to see if the upstream area  23  is clogged requires some effort and assistance. For example, a screwdriver may need to be used to pry the filter element  20  up so that the gasket  26  breaks free of the seat  27  if it has become adhered thereagainst. In accordance with the present invention, a pull tab  40  having free end  42  and an embedded end  44  with an exposed portion  46  of a sufficient area to allow gripping between a thumb and forefinger so that the filter element  20  may be readily removed from the upstream shell  32  for inspection and/or replacement. 
     As is seen in FIGS. 4-7, in the preferred embodiment of the invention, the filter element  20  has a depleted paper of cellulose filter media  50  wherein the downstream area  24  is surrounded by the peripheral gasket  26  and is covered by an expanded metal screen  52 . In the preferred embodiment, the gasket  26  is molded of ethylene-propylenediene modified rubber. In accordance with the preferred embodiment of the invention, the tab  40  is placed between the expanded metal screen  52  and the gasket  26  on the downstream or clean side  24  of the filter element  20 . Although other materials may be used such as plastic or even metal, it has been found that the pull tab  40  functions quite satisfactorily when made from filter media scrap, i.e., the same material from which the filter media  50  is made. This cellulose or paper material is flexible so that while air is being drawn through the filter media  50  and passes through the clean side  24  of the filter media  22 , the pull tab  40  deflects away from the expanded metal screen  52  so as to minimize interference with the flow characteristics of the stream of air being filtered. 
     While the pull tab  40  is shown disposed on a short side  56  of the rectangular filter element  20 , the tab may be disposed at other locations, such as along a long side  58  of the filter element or even in a corner  60  of the filter element. 
     Since the pull tab  40  is adjacent the downstream area or clean side of the filter element  20 , it is exposed to filtered air. Accordingly, the pull tab  40  can be used as an indicator of the effectiveness of the filter media  50 . If the filter media  50  is letting particulate matter pass therethrough, then the particulate matter will impinge on the pull tab  40  and may adhere thereto if the surface of the pull tab  40  is made tacky. In order to enhance this capability, a plurality of pull tabs  40  may be distributed around the periphery of the filter element  20  so that a person observing the tacky undersurface of the pull tabs  40  can determine if particles which have passed through the filter media  50  are adhered thereto. 
     From the foregoing description, one skilled in the art can easily ascertain the essential characteristics of this invention, and without departing from the spirit and scope thereof, can make various changes and modification of the invention to adapt it to various usages and conditions. 
     Without further elaboration, it is believed that one skilled in the art can, using the preceding description, utilize the present invention to its fullest extent. The preceding preferred specific embodiments are, therefore, to be construed as merely illustrative, and not limitative of the remainder of the disclosure in any way whatsoever.