Abstract:
A fastener driver tool fastener load system includes a fastener driving tool having a housing including a magazine with a fastener entry end, an opposite shear block end, and a fastener track defined between the ends. A tensioner is mounted to the housing and includes a driven roller. A plurality of fastener strips is disposed linearly in end-to-end fashion and each strip is secured to each other by at least one fastening tape having a free end connected to the driven roller. The tensioner is constructed and arranged for creating a biasing force for urging the fastener strips toward the shear block end.

Description:
RELATED APPLICATION 
       [0001]    The present application claims priority based on 35 USC §119(e) from U.S. Provisional Application Ser. No. 61/503,837, filed Jul. 1, 2011. 
     
    
     BACKGROUND 
       [0002]    The present invention relates to fastener feed systems for automatic fastener driving tools, and more specifically to a system for providing and loading multiple fastener strips into such a tool. 
         [0003]    In conventional production line applications for fastener driving tools, such as facilities manufacturing, cabinets, other furniture, pre-hung doors, windows or the like, powered staplers are commonly used. Such tools are typically pneumatically powered, but electric tools are also contemplated. To maintain high volume production, the tools are provided with elongated magazines capable of retaining multiple fastener strips, with four to five strips typically accommodated. Even with such magazines, a production line may be shut down for as much as 15 minutes each hour for the reloading of the multiple fastener tools used in production. 
         [0004]    Accordingly, there is an interest by users of such powered fastener drivers for reducing the downtime currently required for reloading the tools with fasteners. 
       SUMMARY 
       [0005]    A system for loading multiple fastener strips into a fastener driving tool is provided, where each strip of fasteners is secured to an adjacent strip by a preferably continuous length of pressure sensitive adhesive tape to form a plurality of connected strips. A sufficient number of strips are connected to each other to form a coil, preferably having a polygonal shape. As the number of strips fastened together by the tape increases, the strips can be stacked in layers. 
         [0006]    At a free end of the tape, a first fastener strip is positioned adjacent a rear end of the fastener driving tool, in operational relationship to the conventional entry point of a fastener strip into the tool magazine. The free end is attached to a powered roller located on the tool, which winds up the tape to create a biasing force, drawing the fastener strips successively into the tool magazine. 
         [0007]    More specifically, a fastener driver tool fastener load system includes a fastener driving tool having a housing including a magazine with a fastener entry end, an opposite shear block end, and a fastener track defined between the ends. A tensioner is mounted to the housing and includes a driven roller. A plurality of fastener strips is disposed linearly in end-to-end fashion and each strip is secured to each other by at least one fastening tape having a free end connected to the driven roller. The tensioner is constructed and arranged for creating a biasing force for urging the fastener strips toward the shear block end. 
         [0008]    In another embodiment, a fastener driver tool is provided for use with a fastener load system including a plurality of fastener strips joined end-to-end with at least one length of tape. The tool includes a fastener tool housing having a magazine with a fastener entry end, an opposite shear block end, and a fastener track defined between the ends. A tensioner is mounted to the housing and includes a driven roller powered by a motor. The tensioner is constructed and arranged for creating a biasing force for urging the fastener strips toward the shear block end. 
         [0009]    In yet another embodiment, a fastener coil is provided that is configured for use with a fastener driver tool fastener load system including a fastener driving tool provided with a driven roller. The coil includes a plurality of fastener strips disposed linearly in end-to-end fashion and secured to each other by at least one fastening tape having a free end connected to the driven roller. Each fastener strip is made up of fasteners having a pair of generally parallel legs spaced by a crown, the at least one tape being secured to the crown of the fasteners. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]      FIG. 1  is a side elevation of a fastener tool equipped with the present enhanced capacity staple load system; 
           [0011]      FIG. 2  is a front perspective view of a stand used to support the coiled fasteners prior to feeding same to the fastener driving tool; 
           [0012]      FIG. 3  is an enlarged fragmentary schematic side elevation of the fastener tool of  FIG. 1 ; 
           [0013]      FIG. 4  is a schematic front view of a fastener that is suitable for use with the present system; and 
           [0014]      FIG. 5  is a fragmentary schematic overhead plan view in partial section of an alternate embodiment of the present system. 
       
    
    
     DETAILED DESCRIPTION 
       [0015]    Referring to  FIGS. 1 and 3 , a fastener driving tool is generally designated  10 , and in the preferred embodiment is a pneumatically powered, staple driver of the type typically used in industrial applications for mass produced assembly of window frames, pre-hung doors or the like. However, it is contemplated that the present system could be employed with other types of fastener driving tools employing conventional linear fastener magazines, including, but not limited to combustion powered and electrically powered tools. 
         [0016]    The present tool  10  includes a tool housing  12  enclosing a driving source  14  (shown hidden), preferably a reciprocating piston and driver blade (not shown) which are well known in the art. A shear block or nose piece  16  is configured for receiving the driver blade from the driving source  14  and creating a chamber for a fastener to be placed in position for being driven into a workpiece upon receipt of impact from the driver blade, as is well known in the art. 
         [0017]    A magazine  18  stores at least one collated strip of fasteners  20 , and is conventionally provided with a spring biased follower and follower handle (not shown) for urging the strip of fasteners  20  towards the shear block  16  for being sequentially driven into the workpiece by the driver blade. A magazine endplate  22  is dimensioned for receiving the strips of fasteners, and typically has an opening that is complementary to, and accommodates the shape of the particular fastener  20 . Between the shear block  16  and the endplate, the magazine  18  defines a fastener track  24 . 
         [0018]    Referring now to  FIGS. 2 and 4 , while other types of fasteners are contemplated, in the present application, the preferred fastener  20  is a staple including a pair of generally parallel, spaced legs  26  each having a sharp point  28 . The legs  26  are separated by a generally linear crown  30  joining upper ends  32  in a single, integral, inverted “U”-shape. The length of the legs  26  varies according to the application. Accordingly, the endplate  22  has a generally inverted “U”-shaped opening dimensioned to complement the profile of the fasteners  20 . 
         [0019]    Referring again to  FIGS. 1 and 3 , in the present tool  10 , the conventional magazine follower, follower handle and return spring are removed, and a powered roller  34  is mounted to the tool housing  12 , preferably near the magazine endplate  22 . The powered roller  34  is powered, either directly or indirectly by a motor  36 , which in the case of a pneumatically powered tool  10 , is preferably a pneumatic motor. Alternatively, the motor  36  is electric, and is provided with a clutch as is known in the art. An idler roller  38  is placed on the tool  10  in operational proximity to the powered roller  34 , and in the preferred embodiment is located closer to the driving source  14  than to the magazine endplate  22 , when compared to the powered roller  34 . Preferably, the idler roller  38  is provided with a resilient, rubber-like cover  40 . 
         [0020]    As seen in  FIG. 3 , an elongate piece  42  of adhesive tape connects the strips of fasteners  20  together, as discussed below. The strip  42  has a free end  44  that is wound around the idler roller  38 , and ultimately is attached to the powered roller  34 . Since it has replaced the conventional magazine follower and spring, the present powered roller  34  is used to pull fastener strips  46  into the magazine  18 , and at the same time, apply pressure on the fasteners  20  already in the magazine, in the manner of a conventional magazine follower spring. As is well known in the art, fasteners  20  in the magazine  18  need to be urged forward towards the tool shear block  16  so they can be driven by the reciprocating driver blade into the workpiece. Sufficient pulling power is provided by the motor  36  to provide enough torque for preventing any slack or space between the fastener strips  46  located inside the magazine  18 . In  FIG. 3 , three such strips  46  are schematically depicted, two in the magazine  18  and a third about to enter the magazine once space is created by use of the fasteners  20  already in the magazine. 
         [0021]    In the present tool  10 , the roller motor  36  is preferably pneumatically powered, and features an adjustable torque setting for coordinating the motor pulling power with the respective air pressure so that just enough force is exerted on the tape  42  to pull the strips  46  into the magazine  18  and keep those fasteners  20  in the magazine under sufficient compression so that they are urged towards the shear block  16 . Such adjustments are contemplated to be variable depending on the application, the workpiece and the type of fastener employed. 
         [0022]    Referring now to  FIGS. 1 and 2 , a plurality of the fastener strips  46  are shown, held together in end-to-end fashion by the tape  42 . With sufficient fastener strips  46  held together, a coil  48  is formed that eventually takes a polygonal shape (here hexagonal), with complementary ends of the strips  46  slightly overlapping or nesting into each other. Other polygonal shapes are contemplated for the coil  48 . In a production environment, the strips  46  are optionally wound upon a spool  50 , which is rotatable relative to a base plate  52 . The motor  36 , the powered and idler rollers,  34 ,  36 , the tape  42  and the coil  48  are collectively referred to as the present enhanced capacity fastener load system  54 . 
         [0023]    The number of fastener strips  46  in the coil  48  formed by the present length of tape  42  is limited only by the available space, the power of the roller motor  36 , and the tensile strength of the tape which secures the adjacent fastener strips together. It is contemplated that as the roller  34  fills with tape  42  with extended use of the tool  10 , the roller can be disposed of. 
         [0024]    In the preferred embodiment, the tape  42  is 3M brand polyester pressure-sensitive tape having a width of approximately ½ inch (1.25 cm). The tape  42  is preferably attached to the fastener strips  46  along the crowns  30  region of the fasteners  20 , which separates the spaced, parallel legs  26  of the staples as described above. During installation, the free end  44  of the tape  42  is preferably wound around the power roller  34  at least 1.5 times, with the adhesive side facing inwardly. Once the tool  10  is activated, the motor  36  is powered, which will draw fastener strips  46  into the magazine  18 . Some applicator assistance may be needed to properly align the fastener strips  46  as they enter the magazine  18 . Once the coil  48  is depleted of fastener strips  46 , the motor  36  will fail to sense further resistance, and will rotate freely. After a new fastener spool  50  is provided, the tool  10  is rapidly restored to operation. 
         [0025]    Referring now to  FIG. 5 , an alternate embodiment of the present system  54  is generally designated  60 . Components shared with the system  54  are designated with the same reference numbers. A main distinguishing feature of the system  60  is that in order to guide the incoming strip  46  of fasteners  20  to the magazine endplate  22 , a magazine rail  62  is located in the fastener track  24  for guiding the fasteners such that the fastener legs  26  straddle the rail. In the system  60 , the magazine rail  62  includes an optional extension  64  that projects beyond the endplate  22  in a tapering configuration that tapers or gradually narrows away from the endplate. A rounded or radiused point or tip  66  is preferably formed at a free end of the extension  64 . This configuration facilitates guiding of the fastener strip  46  into the magazine fastener track  24 . The length and angle of taper of the extension  64  may vary with the application. Other similar shapes of end rail are contemplated for enhancing the alignment of the fastener strip  46  with the magazine fastener track  24 . 
         [0026]    Thus, it will be seen that the present enhanced capacity fastener load system  54  provides operators with a relatively longer operational cycle between reloading, which facilitates production in the respective plant. Fastener reloading is required less often, and is more easily accomplished than when conventional fastener driving tools are employed. 
         [0027]    While a particular embodiment of the present enhanced capacity fastener load system has been shown and described, it will be appreciated by those skilled in the art that changes and modifications may be made thereto without departing from the invention in its broader aspects and as set forth in the following claims.