Abstract:
A coating applicator assembly is disclosed for coating fasteners ends protruding from a surface of a structure, the fasteners extending a specific distance above the surface. In detail, the applicator assembly includes a handle. A coating member made from open celled compressible foam having a coating transfer surface in a generally W shape is attached to the handle. Preferably, the central V of the W shaped surface has an included angle of between 40 and 50 degrees and a depth of between 65 and 85 percent of the specific distance and the outer surfaces of the W shaped surface extending outward at an angle of between 40 and 50 degrees and the depth of coating member is at least 4 times the depth of the central notch.

Description:
RELATED APPLICATIONS 
     This application is a continuation in part of Applicants&#39; co-pending application Ser. No. 10/373,449 An Applicator Assembly For Coating Fasteners by W. T. Mead, et Al., filed Feb. 24, 2003 now abandoned. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to the field of paint applicators and, in particular, to an improved applicator for coating the ends of fasteners protruding from structures. 
     2. Description of Related Art 
     In aircraft manufacture most structural elements are joined with fasteners. For corrosion protection, the surfaces of these structural elements are coated with a corrosion inhibiting coating. After assembly, the structural elements must also have the fastener ends (with retaining nuts attached) coated corrosion inhibiting coatings. Spraying on coatings can be used. However, the corrosion inhibiting coatings typically contain chromium compounds and the use of such sprays may cause environmental problems. Brushes can be used, but there use is time consuming. Thus the use of roller applicators becomes one of most effective methods from both environmental and time considerations. 
     However, prior art roller designs have not been totally effective. A straight roller will not completely cover the fasteners, especially if they are in rows. U.S. Pat. No. 5,410,773 “Pipe Paint Roller” by I. H. Forkner discloses rollers having a U and square shaped notches. These shapes failed to adequately cover in just one pass. In fact, a lot of excess material had to be deposited on the surrounding surfaces before full coverage of the fasteners was accomplished. U.S. Pat. No. 2,929,089 “Paint Applicator For Corners” by W. L. Hall disclosed a roller for corners, with a 90-degree V shaped notch. Tests of this design were also unsuccessful. One of the problems was the shape outer edge collapsed under pressure causing two much of the coating to be deposited on the adjacent surfaces. Thus no prior art applicator design can effectively be used to coat fasteners protruding from a surface. 
     In addition, it is desirable to eliminate the need for an applicator that does not require that the coating material be imbibed by rolling the coating member in a paint tray. This is a time consuming process. Furthermore, it exposes the user to fumes. Additionally, if the coating material is a two-part system (resin and catalyst) it tends to cure rapidly when exposed to air. Thus once the coating material was poured into the paint tray, it had to be applied immediately. 
     Coating material applicators having self-contained supply systems are old in the art. They basically comprised a roller assembly connected by a line to a pump/coating reservoir. Coating flow was controlled by turning the pump on and off. Such systems are difficult to use in confined areas. Examples of this type of applicator can be found in US Patent Publication No. US 2003/0021623A1 “Resin Application” by A. R. Harper. The roller handle incorporates a valve to control resin flow to a spreader bar located in proximity to the roller applicator. U.S. Pat. No. 2,743,469 “Roller Type Paint Applicators” by F. D. Ditch discloses a paint roller wherein the rod extending from the handle to the roller axle and the roller axle itself are hollow. A valve mounted in the handle controls paint flow, which is distributed from the axle into the interior of the roller. 
     There are numerous roller designs wherein the coating material reservoir is contained within the handle. For example, U.S. Pat. No. 3,337,899 “Roller Type Paint Dispenser” by J. M. Rentfrow discloses a device wherein the rod extending from the handle to the roller axle and the roller axle itself are hollow. A reservoir is incorporated into the handle that incorporates a piston biased by a spring that pressurizes the paint therein. A valve is provided for controlling the flow of paint to the roller. However none of these devices disclose a roller applicator suitable for effectively coating the ends of fasteners protruding from a surface. 
     Thus, it is a primary object of the invention to provide a coating applicator for covering the ends of fasteners protruding from a surface. 
     It is another primary object of the invention to provide a coating applicator for covering the ends of fasteners protruding from a surface that covers the ends in one pass. 
     It is a further object of the invention to provide a coating applicator for covering the ends of fasteners protruding from a surface that covers the ends in one pass while applying a minimum amount of coating material to the adjacent surfaces. 
     It is another object of the invention to provide a coating applicator for covering the ends of fasteners protruding from a surface that covers the ends of fasteners, which has a self contained supply of coating material for providing the coating to the applicator for imbibing thereby. 
     SUMMARY OF THE INVENTION 
     In applicants&#39; co-pending patent application Ser. No. 10/373,449 An Applicator Assembly For Coating Fasteners by W. T. Mead, et Al., filed Feb. 24, 2003 disclosed an applicator assembly for coating fasteners ends protruding from a surface of a structure, the fasteners extending a specific distance above the surface. In general terms, the applicator assembly includes a handle to which a coating member is attached made from open celled compressible foam having a coating transfer surface in a generally W shape. In on embodiment the handle includes an axle. A drum is rotatably mounted to the axle. The coating member is in the form of a ring mounted to the drum, the peripheral surface of the ring having the W shape. This embodiment is suitable for coating rows of fasteners. 
     Preferably, the central notch of the W shape has and included angle of between 40 and 50 degrees. The depth of the notch is between 65 and 85 percent of the specific distance the fastener protrudes from the structure. and the outer surfaces of the W shaped surface extending outward at an angle of between 40 and 50 degrees. The total depth of the coating member must be at least 4 times the depth of central notch. Preferably, the foam is open celled having a density of between 2 and 3 pounds per cubic foot. During coating, such a configuration will allow the coating member to deform sufficiently to completely engulf the fastener end and nut insuring that the imbibed coating material completely coats the fastener end and nut. 
     The improvement includes attaching a syringe for containing the coating material to the handle of the applicator assembly having a nozzle replacing the needle. The nozzle is positioned such that the tip of just enters the notch and the outlet port of nozzle is aligned with axis of rotation coating member. The advantage of syringe is that coating material remains within the syringe until applied. With the original applicator assembly, a paint tray was necessary. This exposed the operator and any other individuals near by to fumes and possible contact with coating material when handling the tray or pouring coating material therein. In another version, the syringe includes a spring-biased piston, thus pressurizing the coating material. A valve connected to the output port of the syringe controls the flow of coating material to the roller assembly. 
     The novel features which are believed to be characteristic of the invention, both as to its organization and method of operation, together, with further objects and advantages thereof, will be better understood from the following description in connection with the accompanying drawings in which the presently preferred embodiments of the invention are illustrated by way of examples. It is to be expressly understood, however, that the drawings are for purposes of illustration and description only and are not intended as a definition of the limits of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded view of the roller version of the applicator assembly. 
         FIG. 2  is a cross-sectional view of the assembly illustrated in  FIG. 1  taken along the line  2 — 2 . 
         FIG. 3  is a cross-sectional view of the assembly illustrated in  FIG. 1  taken along the line  3 — 3   
         FIG. 4  is a is a view of the assembly shown in  FIG. 1  applying a coating on a fasteners extending out of the surface of a structure. 
         FIG. 5  is a top view of the assembly shown in  FIG. 1  applying a coating to a series of fasteners protruding from a structure. 
         FIG. 6  is a perspective view of a second embodiment applying a coating to a fastener in a corner of a structure. 
         FIG. 7  is a perspective view of the applicator assembly shown in  FIG. 1  incorporating a syringe for supplying the coating material directly to the applicator. 
         FIG. 8  is an enlarged partial cross-sectional view of  FIG. 7  taken along the line  8 — 8  illustrating the nozzle configuration of the syringe. 
         FIG. 9  is a partially broken away side view of a self-powered version of the applicator assembly. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to  FIGS. 1–3 , the first embodiment of the coating applicator is in the form of a roller assembly, generally designated by numeral  10 , The roller assembly includes a U shaped support frame  12  having a center leg  14  connected at one end to a side leg in the shape of a rod  16  acting as an axle. The rod  16  includes a flange  20  and a threaded end  18 . A roller member  22  is rotatably mounted on the rod  16  retained thereon by flange  20  and a nut  24  engaging the threaded end  18 . The roller member  22  includes a sleeve  26  having a hole  27  through which the rod  16  extends. Bonded to the exterior of the sleeve  26  is a foam coating applicator  28 , which will be subsequently discussed in detail. Also attached to the center leg is a second side leg  32 , which bends 90 degrees at its middle portion  34  and terminates in a threaded end  36 . A handle  38  having an internally threaded end  40  is attached thereby to the threaded end  36 . Thus the roller assembly so far described is conventional in design and other methods of attachment of the roller member  22  can be used. 
     Particularly referring to  FIGS. 2 and 3 , the foam coating applicator  28  is designed to easily imbibe the coating material and coat fasteners  42  installed in structures such as plate assembly  44 . The fastener ends  46  protrude out of the plate assembly  44  with a height  47  and are secured by nuts  48 . In order to properly coat the fastener ends  46  with a minimum of coating material, the peripheral end  50  of the foam coating applicator  28  has a W shape. The center V shaped notch  52  has a depth  54  and an included angle  56 . The outer sides  58 A and  58 B are at acute angles  60 A and  60 B, respectively, leaving only small contact edges  62 A and  62 B. 
     In order to insure that the fastener ends  46  are properly coated in a one or two passes of the roller assembly  10 , the applicator  28  should have the following dimensions: 1. Depth  54  of groove  52  is between 60 to 70 percent of fastener height  47 ; 2. Angle  56  is between 40 and 50 degrees; 3. Angles  60 A and  60 B between 40 and 50 degrees; and 4. Depth  61  of coating applicator is greater than 4 times the depth  54  of the groove  52 . 5. Width  63  of coating applicator is not critical, but must be sufficient to prevent collapse upon application of the coating material. The foam should be open celled foam having a density of between 2 to 3 pounds per cubic foot. As previously stated, during coating, such a configuration will allow the coating member to deform sufficiently to completely engulf the fastener end and nut insuring that the imbibed coating material completely coats the fastener end and nut. Suitable foam is sold under the trade name Artilon®, manufactured by Youngbo America Incorporated, Huntington Beach, Calif. 
     As illustrated in  FIGS. 4 and 5 , when the roller  10  is pressed down over the fastener ends  46 , the roller applicator  28  flattens such the notch  52  deforms about the fastener end  46  causing any imbibed coating material to completely coat the fastener end. Because only the flattened contact edges  62 A and  62 B remain in contact with the plate  44  between fasteners little coating material is deposited between the fasteners as indicated by numeral  64  in  FIG. 5 . Tests have demonstrated that&#39;s other shapes, such as notch or semicircle or 90 V do not work. 
     A second embodiment is illustrated in to  FIG. 6 . Here the applicator assembly, generally indicated by numeral  70 , is shown coating a fastener  72  in a corner of a structure  74 . The applicator assembly  70  includes a simple handle  76  having a plate  77  at end  78 . A block of foam  80  with a W shaped surface  82  is bonded to the plate  77 . It is obvious that this applicator assembly  70  is ideally suited for such situations where a roller assembly could not be effectively used. 
     The applicator assembly illustrated in  FIGS. 1–4  can be improved by incorporating a coating material reservoir. Referring to  FIGS. 6 and 7 , a coating applicator  10 A is depicted that is similar to coating applicator  10  except in the design of the support frame, now indicated by numeral  83 . Here the support frame  83  includes a handle  84  having first and second ends  85 A and  85 B respectively. First and second U shaped spring clips  86 A and  86 B are mounted on the first and second ends  85 A and  85 B of the handle  84 . Each of the U shaped spring clips includes side legs  87 A and  87 B. The support frame  83  includes a center leg  88  that has a first portion  88 A that is bent side ways and second portion.  88 B that is bent downward and joins to a rod  89 , which serves as an axle for the roller member  22 . 
     A syringe  90 , preferably made of plastic material is used as a coating material reservoir. A 10 cubic centimeter capacity is ideal because it has an adequate capacity and can still be operated with one hand. The syringe  90  includes a hollow body  94  with an open first end  96  and closed off second end  98 . The first end  96  of the plunger  100  incorporates flanges  101 A and  101 BA plunger  100  is movably mounted in the open first end  96 . The plunger  100  has a seal  102  at end  104  within the body  94 . Typically, the syringe is filled with a two-part coating  106  comprising a resin and catalyst mixed together. However, other coating materials can be used. The closed off second end  98  has a threaded hole  107  therein, in which a needle (not shown) would be normally installed. The syringe  90  includes a nozzle  108 , which will be subsequently discussed. The syringe  90  is installed by pushing the body  94  of the syringe into engagement with the first and second U shaped members  86 A and  86 B such that the flanges  101 A and  101 B contact end  85 A of the handle  83 . Thereafter, the body  94  is pressed down until the legs  87 A and  87 B of both U shaped  86 A and  86 B lock the syringe in place. Other attachment methods are usable, such as just taping to the handle. 
     The nozzle  108  has an externally threaded end  112 , which engages the threaded hole  107 . The length  114  of the nozzle  108  as well as its shape is such that the outlet port  116  is within the notch  52  of the roller member  22  and is aligned with the axis of rotation thereof. Thus coating material  106  can be applied to the roller member  22  by pressing the plunger  100 , which forces the coating material on to the W shaped peripheral end  50 . As previously stated, the advantage of syringe is that coating material remains within the syringe until applied. With the original applicator assembly, a paint tray was necessary. This exposed the operator and any other individuals near by to fumes and possible contact with coating material when handling the tray or pouring coating material therein. Furthermore, the surface of the coating material in the tray tends to cure rapidly when exposed to air. The syringe  90  once loaded with a two part coating material can be stored at low-temperatures providing a shelf life of up to six months. This is advantageous, since a large number of syringes could be prepared at one time. 
     A third version of the applicator assembly is illustrated in  FIG. 9 , generally indicated by numeral  10 B. The Applicator assembly  10 B includes a syringe  120  that includes an open first end  122  having a flange  123  and a closed off second end  124  having an aperture  126  therein. The syringe  120  includes a twist on cap  130 , which locks on to the flange  123 . A piston  131  is movably mounted within the syringe  120  biased toward the second end  124  by spring  132  positioned between it and the cap  130 . Thus coating material  23  is pushed toward the aperture  126 . A valve  135  includes a body  136  incorporating a plastic tube  137 . A handle  138  is pivotally mounted to the body  136  and rotates about pivot axis  140 . The handle  138  is biased by spring  142  such that the protrusion  144  on the handle normally crimps the tube  137  closing it off. When the handle  138  is pushed toward the body  136  the protrusion  144  disengages from the tube  137  allowing flow through output port  146 . 
     The output port  146  of the valve  135  is connected to the nozzle  108 , which applies coating material to the applicator  28  of the roller assembly  22 . The applicator assembly  22  is rotatably mounted to arm  148  connected to the valve  135 . This embodiment, with automatic feed can more easily operated with one hand. The particular valve  135  has been shown for purposes of illustration only, and there are numerous other types of valves that can be used. The valve depicted is a TS102D Dispensing Pen, manufactured by Techcon Systems, Garden Grove, Calif. 
     While the invention has been described with reference to particular embodiments, it should be understood that the embodiments are merely illustrative, as there are numerous variations and modifications, which may be made by those skilled in the art. Thus, the invention is to be construed as being limited only by the spirit and scope of the appended claims. 
     INDUSTRIAL APPLICABILITY 
     The invention has applicability to the paint industry.