Abstract:
An application tip and method for dispensing sealant into a countersunk hole, the tip having a hollow housing or body with an open end and a closed end; open end configured to be removably attached to and in fluid communication with a sealant source; closed end including a nozzle terminating in cylindrical member having a plurality of passages or fluid outlet openings.

Description:
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
       [0001]    Pursuant to United States Government Contract No. N00019-10-00002, the Government may have certain rights in this invention. 
     
    
     BACKGROUND 
       [0002]    Many countersink fasteners used, for example on airplane structures, require sealant to be applied to countersunk holes before the fastener is inserted. Sealing of the countersunk holes aid in keeping air and fluids from passing in and around the fasteners. The sealant application process is typically performed by hand. 
       SUMMARY OF INVENTION 
       [0003]    The above-mentioned problems of current systems are addressed by embodiments of the present invention and will be understood by reading and studying the following specification. The following summary is made by way of example and not by way of limitation. It is merely provided to aid the reader in understanding some of the aspects of the invention. 
         [0004]    In one embodiment, an application tip is provided. The tip includes a housing having a first end and a second end and an internal passage. The first end of the housing has an opening to the internal passage. The housing also has a dispensing nozzle extending from the second end of the housing, the dispensing nozzle includes a conical member that extends from the second end of the housing and a cylindrical member extending from the conical member, the cylindrical member terminates in a closed end. The dispensing nozzle has at least one dispensing passage that extends along a length of the conical member and the cylindrical member. 
         [0005]    In another embodiment, an application tip is provided. The application tip includes a body having a first end, a second end and an internal passage. The first end is configured to be selectively coupled to a sealant cartridge to receive sealant in the internal passage. The tip has a a dispensing nozzle extending from the second end of the body, the dispensing nozzle includes a conical member having a first end and a second end, the first end of the conical member extends from the second end of the body, the conical member has a diameter that narrows as the conical member extends from the body. The tip further includes a cylindrical member extending from the second end of the conical member, the cylindrical member terminates in a closed end. The dispensing nozzle has at least one dispensing passage that extends a length of the conical member and a length of cylindrical member, and the dispensing passage is configured to dispense sealant from the internal passage. 
         [0006]    In still another embodiment, a method of using an application tip is provided. The method includes: inserting a dispensing nozzle of an application tip in a bore; activating a sealant cartridge that is in fluid communication with the application tip; rotating the dispensing nozzle within the bore to evenly dispense the sealant within a bore portion of the bore and a countersunk portion of the bore; and removing the dispensing tip from the bore. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]    The present invention can be more easily understood and further advantages and uses thereof will be more readily apparent, when considered in view of the detailed description and the following figures in which: 
           [0008]      FIG. 1  is a perspective view of an embodiment of an application tip; 
           [0009]      FIG. 2  is a top view of the application tip of  FIG. 1 ; 
           [0010]      FIG. 3  is a side perspective view of the application tip of  FIG. 1  coupled to a sealant cartridge; 
           [0011]      FIG. 4  is a side view of the application tip of  FIG. 1  in use; and 
           [0012]      FIG. 5  is an application flow diagram of one embodiment of the present invention. 
       
    
    
       [0013]    In accordance with common practice, the various described features are not drawn to scale but are drawn to emphasize specific features relevant to the present invention. Reference characters denote like elements throughout Figures and text. 
       DETAILED DESCRIPTION 
       [0014]    In the following detailed description, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration specific embodiments in which the inventions may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that other embodiments may be utilized and that changes may be made without departing from the spirit and scope of the present invention. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is defined only by the claims and equivalents thereof. 
         [0015]    Typical sealant application processes require an operator to use small dowels (e.g. wood) to apply sealant to a countersunk hole before installing a fastener. An embodiment of a sealant applicator assembly is designed to apply sealant directly from a sealant source such as a sealant cartridge or gun. The sealant applicator assembly further allows for a predetermined sealant amount to be dispensed and evenly coated on the inside surface of a countersunk hole. The above described features result in eliminating the time to transfer sealant from the sealant source to a tray and then from the tray to the dowel. Moreover, fewer materials are wasted during this process. 
         [0016]    Embodiments of the present invention provide an application tip that allows for sealant to be evenly coated in the inside surface of a countersunk bore with a twist of an application gun. Referring to  FIG. 1 , an embodiment of an application tip  100  is illustrated. The application tip includes a cylindrical body or housing  102  having a first end  103  and a second end  104 . The first end  103  is open to an inner passage  130  (shown in  FIG. 2 ). The body or housing includes external threads  105  that are positioned proximate the first end  103 . The threads  105  are used to selectively connect the application tip  100  to a sealant cartridge  300  as further described below. Desirably, any attaching mechanism that is required to engage or otherwise connect application tip  100  to a sealant source is contemplated. 
         [0017]    Proximate the threads  105  are projection members  112  that extend from an outer surface  102   a  of the body  102 . The projections provide grip when connecting and un-connecting the application tip  100  to and from a sealant cartridge  300  described below. 
         [0018]    Extending from the second end of the application tip  100  is a dispensing nozzle  200 . The dispensing nozzle  200  includes a conical member  202  that extends from the second end  104  of the body  102 . The conical member  202  flares inward to negatively mirror the shape of a countersunk portion of a countersunk hole or bore. Moreover, the conical member  202  has a diameter that narrows as the conical member  202  extends from the second end of the body  102 . A cylindrical member  204  extends from the conical member  202  in a direction that is away from the body  102 . The cylindrical member  204  having a shape to fit within a bore portion of a countersunk bore. The cylindrical member  204  terminates in a closed end  206 . The dispensing nozzle  200  further includes at least one dispensing passage or fluid outlet openings  210 . Moreover, the dispensing nozzle  200  preferably includes 4 equally spaced dispensing passages  210 . Each dispending passage  210  extends a length of the conical member  202  and a length of the cylinder member  204 . In one embodiment the dispending passages or openings  210  are slots. The dispensing passages  210  provide a passage for sealant to exit the dispensing nozzle  200  during an application as discussed below.  FIG. 2  illustrates a top view of the application tip  100 . This view illustrates the inner passage  130 , the closed end  206  of the dispensing nozzle  200  and the four equally spaced dispensing passages  210 . This arrangement provides for sealant to be dispensed as a thin layer that evenly coats a bore portion of a bore and a countersunk portion of a countersunk bore or hole. 
         [0019]      FIG. 3  illustrates the application tip  100  coupled to a sealant cartridge  300  that contains sealant. The sealant cartridge  300 , in this embodiment, includes inner threads that threadably engage the external threads  105  of the application tip  100  to couple the application tip  100  to the sealant cartridge  300 . Typically, an application gun (not shown) would be applied to the sealant cartridge  300  to activate the cartridge  300  to dispense sealant.  FIG. 4  illustrates the application tip  100  in use. As illustrated, the dispensing nozzle  210  is inserted into a bore  306  in which a fastener (not shown) is to be received to couple a first structure  302  to a second structure  304 . The counter sunk bore  306  passes through the first and second structure  302  and  304 . As  FIG. 4  illustrates, the cylindrical member  204  of the dispensing nozzle  210  fits within the bore portion  306   a  of the bore  306  and the conical member  202  fits within the countersunk portion  306   b  of the bore  306 . Different size bores will require different size dispensing nozzles  200 . To dispense sealant, the sealant cartridge is activated. This forces sealant (not shown) out the dispensing nozzles  210 . As the sealant is dispensed, the application tip  100  is rotated one quarter turn in one direction to evenly dispense sealant in the bore portion  306   a  and the countersunk portion  306   b  of the bore  306 . If only three equally spaced dispensing passages  210  are present in the dispensing nozzle  200 , the dispensing nozzle would need to be rotated one third a turn to dispense the sealant evenly. Moreover, if only two spaced dispensing passages  210  where present in the dispensing nozzle  200 , the dispensing nozzle would need to be rotated one half turn to dispense the sealant evenly and the like. Hence, the number of dispensing passages determines the rotation needed to evenly spread the sealant in the bore. 
         [0020]      FIG. 5  illustrates an application flow diagram  500  of an embodiment. The process starts by attaching an application tip  100  to a sealant cartridge  300  ( 502 ). The dispensing nozzle  210  of the application tip  100  is then placed in a countersunk bore  306  ( 504 ). The sealant cartridge age  300  is then activated ( 506 ). As discussed above, this is typically done with an application gun that forces out the sealant from the sealant cartridge  300  into the application tip  100  and out the dispensing passages  210 . The application tip  100  is then rotated to evenly dispense the sealant within the bore  306  ( 508 ). Rotation of the application tip  100  would typically be accomplished by rotating the application gun. After rotation, the dispensing nozzle  200  of the application tip is removed from the bore  306  ( 510 ). A fastener (not shown) is then fastened within the bore ( 512 ). 
         [0021]    Application tip  100  may have for example a diameter of at least or about 0.3 to 0.6 inches or any range or value therebetween. Depending on the fastener and countersink to be sealed, other diameters for application tip  100  beyond those shown in  FIG. 2  are possible. The diameter of dispensing nozzle  200  is dimensioned such that clearance between the diameter of application tip and the diameter of the hole is such that it controls how much sealant is applied to the hole. 
         [0022]    Application tip  100  is desirably dimensioned and configured to dispense metered amounts of sealant to form a continuous sealant ring over the countersunk hole. Application tip  100  desirably meters out an incremental sealant portion. The metered amount will be a function of several factors including application tip  100  length, the dispensing passage or opening length, size and shape. Desirably, application tip  100  is configured and dimensioned for attaching to commercially available sealant cartridges, for example sealant cartridges available from Semco Inc. 
         [0023]    Application tip  100  can be made from any suitable material, such as, but not limited to, stainless steel or other acceptable metal or alloy. Other materials suitable for the application tip  100  include, but are not limited to, polyvinyl chloride (PVC), nylon, polyether ether ketone (PEEK), acrylonitrile butadiene styrene (ABS) and the like. 
         [0024]    Although specific embodiments have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that any arrangement, which is calculated to achieve the same purpose, may be substituted for the specific embodiment shown. This application is intended to cover any adaptations or variations of the present invention. Therefore, it is manifestly intended that this invention be limited only by the claims and the equivalents thereof.