Abstract:
A filter head adaptor for a compressed air filter. The filter head adaptor capable of modifying a filter head to accommodate a variety of different style filter elements. The filter head adaptor including a main body connector, a filter element connector, and a second inlet channel in fluid communication between the main body connector and the filter element connector, the main body connector is adapted for coupling to the adaptor connector of the main body, whereby the main body connector is adapted for coupling to a filter head. The invention includes contemplates requiring a reduced inventory of filter heads and filter bodies for a plurality of filter elements, as the appropriate filter head adaptor may be selected which presents a particular filter element connector which matches that of the filter element intended to be used.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to a compressed air filter, and in particular, an adaptor for coupling a filter element and filter head in a compressed air filter. 
       BACKGROUND OF THE INVENTION 
       [0002]    The prior art includes general air treatment technology, such as compressed air filters, dust filters, general purpose filters, coalescing filters and activated carbon filters. The compressed air filters may include a filter body containing a filter element which couples to a filter head. The filter head typically includes the fittings for connecting the filter into a compressed air system. The filter element requires periodic replacement to maintain the performance of the compressed air system. In particular, a standard schedule for filter element replacement significantly lowers the pressure drop loss across the compressed air system. 
         [0003]    To accommodate ease in replacement of the filter element, the fittings for coupling to the compressed air system are generally limited to the filter head. The filter body contains the filter element and, with the exception of the drain, includes no attachments to the compressed air system. Thus, the filter body is designed for easy removal from the compressed air system together with the filter element for easy replacement of the filter element. 
         [0004]    The prior art filter heads include various different configurations, including the ports, chamber and interface to the filter element and filter body. Each style of configuration of filter head requires a filter body and filter element with a corresponding configuration in order to provide a sealed filter with optimum flow characteristics. 
         [0005]    The main problem with the prior art is the required manufacturing of each component part and the corresponding inventory required for each part, to support the assembly of the various systems. 
       SUMMARY OF THE INVENTION 
       [0006]    It is an object of the present invention to provide and accommodate various style and size filter elements and overall filter systems and yet reduce the overall component count. 
         [0007]    It is a further object of the present invention to reduce the inventory of filter components. It is still a further object of the present invention to provide an adaptor for a filter which may be used for more than one style filter element. 
         [0008]    It is yet a further object of the present invention to provide a filter head with a more cost efficient smooth fluid flow feature. 
         [0009]    The present invention provides a filter head adaptor for a compressed air filter. The filter head adaptor is capable of adapting a filter head to accommodate a variety of different style filter elements. The filter head adaptor including a main body connector, a filter element connector, and a second inlet channel in fluid communication between the main body connector and the filter element connector, the main body connector is adapted for coupling to the adaptor connector of the main body, whereby the main body connector is adapted for coupling to a filter head. 
         [0010]    The filter head includes a main body, the main body including an inlet port, an adaptor connector, a first inlet channel in fluid communication between the inlet port and the adaptor connector, a filter body connector, an outlet port, and an outlet channel in fluid communication between the filter body connector and the outlet port, whereby the first and second inlet channels form a continuous inlet channel between the inlet port and the filter element connector. 
         [0011]    The adaptor and filter head main body allow a cost efficient design of a filter head which provides an inlet channel having a smooth fluid flow channel. 
         [0012]    Considering the above comments, it will be appreciated that with an inventory of a single filter head, a single filter bowl, and a plurality of adaptors, the inventory will accommodate the assembly of a filter for any one of a plurality of filter elements. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]      FIG. 1  is a part perspective view and part cross-sectional view of a prior art compressed air filter; 
           [0014]      FIG. 2  is an enlarged view of a portion of the part perspective view and part cross-sectional view of the prior art compressed air filter of  FIG. 1 ; 
           [0015]      FIG. 3  is an elevated view of a compressed air filter in accordance with the present invention, showing the filter head and filter body; 
           [0016]      FIG. 4  is an exploded view of the filter head of  FIG. 3 , including an adaptor and means for fastening, in accordance with the present invention; 
           [0017]      FIG. 5  is a perspective view of the adaptor shown in  FIG. 4  in accordance with the present invention; 
           [0018]      FIG. 6  is an elevated view of the adaptor shown in  FIGS. 4 and 5 , in accordance with the present invention; and 
           [0019]      FIG. 7  is a part perspective view and part cross-sectional view of another embodiment of a compressed air filter, in accordance with the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0020]      FIG. 1  and  FIG. 2  show a prior art compressed air filter  10 . The compressed air filter  10  includes a filter head  12 , a filter body  14  and a filter element  16 . The filter head  12  includes an inlet passage or channel  18  formed by an inlet wall  20  and an outlet passage or channel  22  formed by an outlet wall  24 . The inlet passage  18  includes a first end  26  in fluid communication with an inlet port  28  and a second end  30  in fluid communication with a first filter element port  32  ( FIG. 2 ). The outlet passage  22  includes a first end  34  in fluid communication with a second filter element port  36  ( FIG. 2 ) and a second end  38  in fluid communication with an outlet port  40 . 
         [0021]    The filter head  12  further includes a filter element connector  42  and a filter body connector  44 . The filter element connector  42  includes a first cylindrical collar  46  which forms the first filter element port  32 . The first cylindrical collar  46  extends downward from the filter head  12  and includes an inner cylindrical wall  48  and a lower annular edge  50 . A first abutement or stop  52  is provided at an upper end of the inner cylindrical wall  48 . The first cylindrical collar  46  includes an outside diameter, an inside diameter, and a length between the stop  52  and lower annular edge  50 . The filter body connector  44  includes a second cylindrical collar  54  having an inside diameter which is larger than an outside diameter of the first cylindrical collar  46 . The second cylindrical collar  54  includes an internal wall  56  having a thread  58 . The second filter element port  36  is generally annularly shaped and is formed between the first cylindrical collar  46  and the second cylindrical collar  54 . 
         [0022]    The filter body  14  includes a generally cylindrical body  70  having a closed lower end  72  and an open upper end  74  which define a cavity  76 . The closed end  72  includes a drain line  78 . The upper end  74  includes an annular collar  80  having an outer wall  82  with a thread  84  and an inner wall  86  with a ledge  88 . Vertical ribs  90  are formed within the cavity  76  of the cylindrical body  70  at the closed lower end  72 . 
         [0023]    The filter element  16  includes an upper end cap  100  and a lower end cap  102 . The end caps  100 ,  102  may be made of nylon or another material. A cylindrical mesh wall  104  extends between the upper end cap  100  and the lower end cap  102 . The cylindrical mesh wall  104  includes a plurality of openings  106 . A cylindrical filter media  108  is enclosed within the end caps  100 ,  102  and cylindrical mesh wall  104 . The filter media  108  forms an inner cylindrical fluid channel  110  between the upper end cap  100  and the openings  106  in the cylindrical mesh wall  104 . Radial extensions  112  extend outwardly from the upper end cap  100 . A collar  114  extends upward from the upper end cap  100 . The collar  114  includes an upper edge  116  and an outer wall  118 , the outer wall  118  provided with two o-rings  120 . The collar  114  includes an outer diameter, and inner diameter and the outer wall  118  includes a length. 
         [0024]    The prior art compressed air filter  10  is assembled by inserting the filter element  16  into filter body  14 . The lower end cap  102  will abut the vertical ribs  90  and the radial extensions  112  will abut the ledge  88 . The combination filter body  14  and filter element  16  is then inserted into the filter head  12  and threaded into place with the threads  84  of the filter body  14  engaging the threads  58  of the filter head  12 . The advancement of the filter body  14  and filter element  16  into the filter head  12  will be stopped by full engagement of the threads  84 ,  58  and the upper edge  116  with the first abatement  52 , and the lower annular edge  50  with the upper end cap  100 . 
         [0025]      FIG. 3  shown a compressed air filter  200  in accordance with the present invention. The compressed air filter  200  includes a filter head  202  and a filter body  204 . The compressed air filter  200  shares many features with the compressed air filter  10 . The same reference numerals are used to show the similar features. However, as shown in  FIG. 4 , the present invention includes a filter head  202  having an adaptor  300 . 
         [0026]    The adaptor  300  is shown in exploded view. However, it will be appreciated that the adaptor  300  is secured to the filter head  202  via a fasteners, such as screws  302 . The screws  302  are received by bores or holes  304  which extend through the adaptor  300 . The bores  304  may be formed with an inside diameter larger than the outside diameter of the screws  302 . 
         [0027]    Instead of fasteners, the adaptor  300  may be secured to the head  202  via a snap-fitted arrangement, a threaded connection, an adhesive attachment, or any other means of securing the adaptor to the filter head as understood by one skilled in the art. The filter head  202  includes a main body  306  generally defined by an outer wall  308  and a top wall  310  which together define a cavity  312  in the main body  306 . The filter head  202  includes a rim  314  which in the embodiment shown in  FIG. 4  presents an elliptical profile. The rim  314  includes a groove ( FIG. 7 ) which receives a seal, such as O-ring  316 . Threaded bores or openings  318  surround the rim  314  and are adapted to receive a respective screw  302 . As shown in  FIG. 5 , the adaptor  300  includes a mating surface  320  for sealing engagement with the rim  314  and O-ring  316 . 
         [0028]    It will be appreciated that the rim  314  and the adaptor  300  define in part the inlet passage  18  of the filter head  202 . In particular,  FIG. 4  shows that the filter head  202  includes a wall  322 , in this instance, providing an elliptical profile. The wall  322  includes an opening  324  which further defines the inlet passage  18 . The wall  322  is bordered at one end by the rim  314  and at the other end by an end wall  326 . The shape of the wall  322  and other portions of the inlet passage  18  define a transition portion  328  of the inlet passage  18 , and are designed, in part, to provide excellent fluid flow through the transition portion  328 . 
         [0029]      FIGS. 4 and 5  shows that the adaptor  300  defines two primary fluid flow profiles within the inlet passage  18 , namely, an initial fluid flow profile  330  and a final fluid flow profile  332 . The initial fluid flow profile  330  is defined in part by the mating surface  320  of the adaptor  300 . The mating surface  320  presents an elliptical and inclined profile which corresponds to the shape of the rim  314 . A wall  334  extends from the mating surface  320  initially with a similar elliptical profile. However, it can be seen that the wall  334  extends in a smooth curved like manner, changing the profile of the inlet passage  18 . The wall  334  meets a transition portion  336  which separates the initial fluid flow profile  330  and the final fluid flow profile  332 . In the embodiment shown in  FIGS. 4 and 5 , the final fluid flow profile  332  is shown to be substantially cylindrical. As noted above, it will be appreciated that various profiles may be chosen to enhance the fluid flow characteristics of the filter, and also to accommodate the various style filter elements. 
         [0030]      FIGS. 4-6  show that the adaptor  300  includes the filter element connector  42  having the first cylindrical collar  46  and the lower annular edge  50 , and the first abutement or stop  52 . It will be appreciated that the adaptor  300  may be designed to provide a particular style filter element connector  42  dependent upon the filter element in which it is intended to mate. Thus, various different adaptors  300  may be provided, each having a particular style filter element connector  42 . It is anticipated that in some embodiments, the filter element connector  42  may be designed to mate with more than one filter element. 
         [0031]      FIG. 6  shows that the adaptor  300  includes a main body portion  338 . The main body portion  338  is shown to include a flat planar surface  340 . The main body portion  338  includes an extension portion  342  which largely corresponds to the elliptical shape of the mating surface  320  and rim  314 . 
         [0032]    The adaptor  300  allows the use of one filter housing, e.g., combination filter head  202  and filter body  204 , for two different customers. Each adaptor  300  may provide one of several different connection diameters for different filter elements  16 . In addition, the nature of the adaptor  300  allows for designing a smooth flow feature in the assembled combination head  202  and adaptor  300 . Such design feature is much more difficult to achieve in a prior art one piece head. 
         [0033]      FIG. 7  is a part perspective view and part cross-sectional view of another embodiment of a compressed air filter  200 , in accordance with the present invention. As noted above, the rim  314  includes a groove. The adaptor  300  shown in  FIG. 7  includes a flange which is received by the groove of the rim  314 , providing a tongue-and-groove arrangement. 
         [0034]    While the present invention has been described in connection with a specific application, this application is exemplary in nature and is not intended to be limiting on the possible applications of this invention. It will be understood that modifications and variations may be effected without departing from the spirit and scope of the present invention. It will be appreciated that the present disclosure is intended as an exemplification of the invention and is not intended to limit the invention to the specific embodiments illustrated and described. The disclosure is intended to cover, by the appended claims, all such modifications as fall within the scope of the claims.