Abstract:
A filter includes a relatively rigid support frame having top and bottom frame members and side frame members. A filter element is disposed within and supported by the frame for filtering a medium passing through the filter element. Two opposing members of the frame are bendable into an arch to allow the filter to be progressively inserted along an arched path into a filter housing. In one embodiment, the filter is a cabin air filter for a vehicle and opposing sides of the frame are provided with V-shaped notches to facilitate bending the filter into an arch for insertion.

Description:
REFERENCE TO RELATED APPLICATION 
       [0001]    Priority is hereby claimed to the filing date of U. S. provisional patent application 61/890,917 entitled Segmented Bendable Filter, which was filed on Oct. 15, 2013. 
     
    
     TECHNICAL FIELD 
       [0002]    This disclosure relates generally to filters and, in a preferred embodiment, to a cabin air filter for a vehicle such as a truck or automobile. 
       BACKGROUND 
       [0003]    Many trucks and automobiles have ventilation systems that includes a cabin air filter that filters air before it is expelled into the passenger compartment. Cabin air filters should be changed regularly to insure that occupants of the vehicle are provided with fresh filtered air when using the air conditioning, vent, or heater. In some vehicles, changing the cabin air filter is straight forward and simply requires the removal of a cover plate, removal of the old filter, and insertion of a fresh filter. In these vehicles, there is ample space between the vent and filter housings and the floorboard or other interior structures to allow access and replacement. However, in some vehicles and in particular in the cabs of trucks such as pickup trucks, the filter housing can be located in the cabin beneath the dash directly above the rather large hump in the floor that accommodates the transmission. Further, the filter housing that contains the cabin filter in these situations is accessible only from below through a removable filter access port. Since the cabin air filter itself is significantly longer than the space between the filter access port and the transmission hump, it can be difficult to remove the old filter and even more difficult to install a new filter without damaging or destroying the filter itself. This is because the air filter must be bent, twisted, and otherwise contorted to slide it up into the filter housing and this can cause glue joints and frame elements supporting the filter element to break or otherwise fail. 
         [0004]    There is a need for a filter and particularly a cabin air filter for vehicles that can be installed easily in a filter housing located in tight and cramped quarters without damaging or destroying the filter. It is to the provision of such a filter that the present invention is primarily directed. 
       SUMMARY 
       [0005]    Briefly described, a cabin air filter for a vehicle has a support frame that supports a filter element such as a pleated fibrous filter element. The sides of the frame are provided with V-shaped notches that define frame segments to which opposing sides of the filter element are glued or otherwise attached. Due to the notches, which are aligned from side-to-side of the filter, the filter can be bent easily into an arch without damaging the filter, its frame, or the filter element. To install the filter, an access panel is removed from the air filter housing and the old filter is removed through the access port. A filter according to the present invention can then be bent into an arch and progressively slid along an arched path through the access port into the filter housing. As the filter moves into the filter housing, it progressively flattens back to a planar shape until it is completely inserted into the filter housing. The filter can thus be slid easily through an access port that is located in tight or cramped quarters, which is common in certain vehicles such as truck cabs. The access panel is then reinstalled and the new filter fulfills its role to filter cabin air. These and other aspects, features, and advantages of the invention disclosed herein will become apparent to the skilled artisan upon review of the detailed description set forth below taken in conjunction with the accompanying drawing figures, which are briefly described as follows. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]      FIG. 1  is a perspective view of a segmented bendable filter that embodies principles of the invention in one preferred form. 
           [0007]      FIG. 2  illustrates a typical cabin air filter housing showing the outer cover and access panel removed to reveal the filter access port of the housing. 
           [0008]      FIG. 3  illustrates the filter of the present invention bent into an arch and just being inserted through the access port of a filter housing. 
           [0009]      FIG. 4  shows sequentially the progressive insertion of the filter along an arched path into the filter housing to accommodate the cramped space between the access port of the filter housing and the transmission hump below. 
       
    
    
     DETAILED DESCRIPTION 
       [0010]    The entire content of the provisional patent application to which priority is claimed above is hereby incorporated by reference. 
         [0011]    Referring now in more detail to the drawing figures, wherein like reference numerals indicate like parts throughout the several views,  FIG. 1  shows a filter that embodies principles of the invention in one preferred form. The filter shown in  FIG. 1  is specifically configured as a cabin air filter for a vehicle and particularly a pickup truck, and the invention will be described in this context. It will be appreciated, however, that the invention is not limited to a cabin air filter or a vehicle filter at all, but rather is applicable to any filter that must be installed through an access port that is located in tight or cramped quarters making access difficult. Consequently, the invention may apply to home HVAC filters, industrial air filters, or even to fluid filters that are difficult to access and replace. 
         [0012]    Referring again to  FIG. 1 , a filter  11  has a left side  12 , a right side  13 , a top side  14  and a bottom side  16 . The left, right, top, and bottom sides form a support frame within which a pleated air permeable filter element  17  is disposed. The filter element is secured with adhesive or sealant to the frame to prevent air leaks between the filter element and the frame. The top side  14  of the frame includes an elongated relatively rigid support  24  spanning the width of the filter  11 . Similarly, the bottom side  16  of the frame includes an elongated relatively rigid support  27  that also spans the width of the filter  11 . In the preferred embodiment, a rubberized gasket  26  is attached along the outside of the top side support  24  and a rubberized gasket  28  is attached along the outside of the bottom side support  27 . These gaskets seal against walls of a filter housing when the filter is installed to minimize air leaks around the outside of the frame. Pull tabs  29  extend from the bottom side  16  to provide a structure that can be grasped to pull the filter from its housing when it is spent and needs replacement with a fresh filter. 
         [0013]    The left side  12  of the support frame is made of a relatively rigid strip of material  19  and is formed with a series of V-shaped notches  22  that extend from the back side of the strip  19  toward the front side. The V-shaped notches  22  define a plurality of tabs  21  in the strip  19 . A rubberized gasket strip  23  is adhered along the outside of the strip of material  19  for engaging and sealing against a wall of a filter housing to reduce air leaks. The V-shaped notches in the illustrated embodiment extend into the gasket, but this is not a requirement and the notches may stop short of or not be cut into the gasket itself if desired. The gasket, which preferably is made of a stretchy material such a rubber or foam, helps to insure that the filter reconfigures itself into a planar shape after having been bent and inserted into a filter housing as detailed below. The right side  13  of the frame is a mirror image of the left side  12  and includes a relatively rigid strip  20  of material formed with notches  33  that define segments  34 . While not visible, the right side  13  also includes an exterior rubberized gasket to seal against a wall of a filter housing within which the filter  11  is installed and to help re-flatten the filter once it is inserted into the filter housing. 
         [0014]    A pleated filter element  17  is mounted within the support frame  19  and is made of a woven or non-woven or other filter material that passes air but traps suspended dust, pollen, and other particles that may be entrained within the air. Such materials are known in the art. The material of the filter element is accordion folded to form a plurality of pleats  31  that extend from the left side support frame to the right side support frame. The side edges of the pleated filter element are secured to the sides of the support frame with an appropriate sealant or adhesive. Further, one of the pleats of the filter element is aligned with each one of the V-shaped notches in the sides  12  and  13  of the support frame. In this way, the filter element does not inhibit the spreading apart of the V-shaped notches when the filter is bent into an arch during installation. A relatively rigid support strip  32  preferably is adhered to one side of each aligned pleat to provide side-to-side support to the filter element when the filter is bent into an arch. Finally, the top and bottom pleats of the filter element are secured with adhesive to the top and bottom supports  24  and  27  of the frame with an appropriate adhesive. 
         [0015]      FIGS. 2-4  illustrate the installation of a filter according to this invention into the ductwork of a vehicle&#39;s HVAC system. In this event, the HVAC system is of a Chevrolet® Silverado® pickup truck, which is notorious for providing a small confined space within which to access and change the cabin air filter.  FIG. 2  shows the HVAC ductwork  41  within the passenger compartment beneath the dash after the outer cover or kick plate has been removed. The ductwork  41  defines a filter housing  43  within which a cabin air filter resides. Rectangular access port  44  provides access to the filter housing for removing and replacing the cabin air filter. While not visible in  FIG. 2 , the transmission hump in the referenced vehicle is disposed just beneath the access port  44  a distance significantly less than the height of a cabin air filter to be inserted through the access port  44 . This confined space makes it difficult to remove and replace traditional rigid cabin air filters. 
         [0016]      FIG. 3  shows the first stage of insertion of a cabin air filter of the present invention into the filter housing shown in  FIG. 2 . Here, the transmission hump  49  is visible just below the access port  44  and it can be seen that the height of the filter  46  is significantly greater than the distance from the access port to the transmission hump. In  FIG. 3 , the filter  46  has been bent into an arch as described with its tabs  21  splayed apart and its V-shaped grooves spread to accommodate the bending. The top end of the arched filter is being urged through the access port  44  and into the filter housing in the direction of arrow  47 . 
         [0017]    In the upper left image of  FIG. 4 , the filter  46  has been inserted a bit further through the access port and in the upper right image a bit further still. The lower left image shows all but the last two segments of the filter  46  inside the filter housing and the lower right image of  FIG. 4  shows the final step of the last segment of the filter moving through the access port into the housing. As the arched filter moves through the access port and into the housing, it naturally straightens out to conform to the flat planar shape of the housing and is aided in this regard by the rubberized side gaskets and the filter stops within the gasket housing. When the gasket is fully inserted into the gasket housing, it takes on the flat configuration shown in  FIG. 1  and functions as a normal cabin air filter to filter air drawn into or circulated within the passenger cabin of the vehicle. 
         [0018]    When it is time to remove the cabin air filter of this invention, the process is simply reversed. The access port is opened and the filter is grasped by its tabs  29  ( FIG. 1 ) and pulled out through the access port of the filter housing. During removal, the filter may again bend into an arch to allow it to be removed cleanly, smoothly, and easily. This can be important since used filters generally are covered with dust and pollen that could be released into the vehicle&#39;s passenger compartment if the filter were removed in a jerky torturous manner, as is common with traditional rigid cabin air filters. 
         [0019]    The invention has been described herein in terms of a preferred embodiment and a preferred methodology considered by the inventor to represent the best mode of carrying out the invention. It will be understood by those of skill in the art, however, that the invention is not limited by the preferred embodiment or the context within which it is described. In fact, the inventive filter of this disclosure can be used in virtually any scenario where a filter is to be removed and replaced in tight, confined, or otherwise cramped spaces. Thus, the invention can be applied to home air conditioning and heating filters, office HVAC filters, and even oil and hydraulic fluid filters. These and other additions, deletions, and modifications may well be made to the preferred embodiments illustrated herein without departing from the spirit and scope of the invention, which is delimited only by the claims.