Abstract:
The present invention relates generally to a fastener retaining system (FRS) and kit for securing a fastener (such as a screw) to a driver (such as a screwdriver) to facilitate one-handed use of the driver in both fastening and un-fastening operations.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
   This application is a continuation-in-part of U.S. patent application Ser. No. 11/426,253 filed Jun. 23, 2006, now abandoned. 

   FIELD OF THE INVENTION 
   The present invention relates generally to a fastener retaining system (FRS) and kit for securing a fastener (such as a screw) to a driver (such as a screwdriver) to facilitate one-handed use of the driver in both fastening and un-fastening operations. 
   BACKGROUND OF THE INVENTION 
   In the use of fastener-drivers (hereafter a “driver” or “drivers”), users often seek ways to ensure that the fastener remains fixed to the driver. More specifically, at many times, a user desires to use only one hand to apply pressure to the fastener as a result of the desired placement or location of the fastener. In situations where the desired placement of the fastener is on a vertical work surface or a work surface below the driver, the user must usually hold the fastener against the driver to ensure that it does not fall off the driver during positioning. Alternatively, the user must use steady hand movements while placing the fastener against the work surface. While some fasteners or drivers (such as a ROBERTSON™ driver and fastener) have specific surfaces or properties allowing the fastener and driver to remain gently attached to one another, the fastener may often fall off the driver if a critical angle is reached, the user inadvertently touches another surface with the fastener or as a result of unsteady hand or body movements by the user. 
   In the past, one solution to this problem has been the use of magnets within the driver which can increase the relative strength of connection between the driver and fastener. However, as a magnet requires that a corresponding fastener is magnetic, magnet tip drivers are limited to use with magnetic fasteners. Magnet tip drivers also have a tendency to pick up stray metal filings in and around work projects that must be periodically cleaned from the driver. Still further, magnet tip drivers are not suitable around magnet- and electrically sensitive areas where live wires may be employed. A magnet tip driver may also be unnecessarily bulky thereby limiting its use in certain applications. 
   Other past solutions have included screwstarters and screw guides. Screwstarters utilize either a spring-loaded or manually actuated multi-sectioned bit to apply opposing pressures to opposite sides of a fastener. However, these systems are limited to either a specific fastener style or a relatively small number of fastener styles. Moreover, these systems are relatively expensive compared to a single component driver. Screw guides are spring loaded rigid sleeves that are biased over the tip of a driver and that retract up and over the shaft as a fastener is advanced into a surface. These systems are generally limited to a particular size fastener head and are not interchangeable between different bits. 
   The prior art reveals that the use of flexible sleeves that engage with the shaft of a screwdriver have been proposed in various forms. While various embodiments of fastener holding devices are described within the prior art, the prior art does not disclose a fastener holding system that permits the use of a single fastener retaining system that can be effectively used with a wide-range of fastener head diameters and that ensures the effective capturing, centering and release of fasteners within the fastener holding device. 
   A review of the prior art reveals that such a system has not been previously disclosed. For example, U.S. Pat. Nos. 3,245,446, 4,221,429, 4,936,171, 3,351,111, 5,029,498, 1,126,370 each describe various screw holding devices that may be used to retain or hold a screw against a screwdriver. However, none of these references provide a system that enables the effective centering of a fastener within the system that ensures the effective centering of the fastener within the system or that are readily adapted for use with screwdriver shafts of different cross-sections. 
   SUMMARY OF THE INVENTION 
   In accordance with the invention, there is provided a system for retaining a fastener against a driver bit comprising: a resiliently flexible sleeve for frictional engagement against a driver shaft, the sleeve including at least three inwardly projecting arcuate leaflets adjacent a first end of the sleeve for engagement over and around the head of a fastener. 
   In a further embodiment, the leaflets abut each adjacent leaflet thereby defining an abutment region and wherein the abutment region extends greater than 50% of the distance between the sleeve and the central axis of the sleeve. 
   In another embodiment, each leaflet has a horizontal length extending from the sleeve that is less than the vertical displacement of each leaflet from the first end of the sleeve. 
   In one embodiment, the first end of the sleeve is inwardly tapered towards the leaflets thereby defining a volume radial to the leaflets for allowing a leaflet to fold into the volume during use. 
   In another embodiments, the sleeve has either a generally triangular cross-section that may be inwardly convex or a circular cross section. 
   In a more specific embodiment, the invention provides a system for retaining a fastener against a driver bit comprising: a resiliently flexible sleeve for frictional engagement against a driver shaft, the sleeve having a triangular cross section having three inwardly convex surfaces, the sleeve further including at three inwardly projecting arcuate leaflets adjacent a first end of the sleeve for engagement over and around the head of a fastener and wherein each leaflet has a horizontal length that is less than the vertical displacement of each leaflet from the first end of the sleeve. 
   Further still, the invention provides a driver for securing a sleeve as described wherein the driver includes a head having a recess for receiving and storing the sleeve. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Embodiments of the invention will be described, by way of example with reference to the attached Figures, wherein: 
       FIG. 1  is a cross-sectional view of a fastener holding system in accordance with one embodiment of the invention; 
       FIG. 2  is perspective view of a fastener holding system in accordance with one embodiment of the invention; 
       FIG. 3  is perspective and cross-sectional view of a fastener holding system in accordance with one embodiment of the invention; 
       FIGS. 3A ,  3 B and  3 C are end views of different leaflet configurations in accordance with various embodiments of the invention; 
       FIG. 4  is an end view of a fastener holding system in accordance with one embodiment of the invention; 
       FIG. 5  is a cross-sectional view of the lower section of a fastener holding system in accordance with one embodiment of the invention; 
       FIG. 6  is a cross-sectional view of the sleeve of a fastener holding system in accordance with one embodiment of the invention; 
       FIG. 7  is a cross-sectional view of the lower section of a fastener holding system in accordance with one embodiment of the invention showing a leaflet in folded position; and, 
       FIG. 8  is a cross-sectional view of a driver head in accordance with an embodiment of the invention wherein the driver head has a recess for storing a sleeve. 
   

   DETAILED DESCRIPTION 
   With reference to the Figures, an elastic and flexible polymeric fastener retaining system (FRS)  10  is described for use in retaining fasteners  5  against the bit surfaces  11  of a driver  11   a . The invention is described by way of two preferred embodiments. 
   As shown in  FIG. 1 , the FRS  10  includes a sleeve  12  for frictional engagement around the shaft of a driver  11   a  (such as a screwdriver shaft) and a lower section  14  adapted for engagement with a fastener. In the embodiment shown in  FIG. 1 , the sleeve  12  generally has an inside diameter corresponding to the outer diameter of the driver shaft  11   a  while the lower section  14  has an inside diameter which allows the lower section  14  to be placed over the head  5   a  of a fastener  5 . 
   In the embodiment shown in  FIGS. 2 and 3 , the sleeve  12  has a generally triangular cross-section. 
   In each embodiment, the inner surface of the lower section is provided with a fastener retaining system  16  comprising at least three leaflets  15  adjacent the lower edge  14   a.    
   In operation, a user places the sleeve  12  over and around the shaft  11   a  of a driver and positions the lower edge  14   a  of the lower sleeve so that it protrudes slightly beyond the lower tip of the driver bit. A fastener  5  is inserted within the fastener retaining system so as to engage with the bit surface  11  where it is firmly held against the bit surface. By virtue of the leaflet design together with the elastic and flexible nature of the FRS, variations in fastener head and shaft diameters can be retained against a bit surface. 
   Lower Section 
   As best shown in  FIGS. 2 ,  3  and  4 , the lower section  14  includes three generally arcuate leaflets extending inwardly from the inner surfaces of the shaft sleeve  12 . The arcuate leaflets may have different radii as shown in  FIGS. 3A ,  3 B and  3 C whereby leaflets of different radii define openings  15   a  of varying area between the leaflets. As shown, the outer edge surface of each leaflet extends to the interior of the FRS wherein, depending on the radius of the leaflet, may abut the outer edge surface  15   a  of an adjacent leaftlet. That is, as shown in  FIG. 3A , where the radii of each of the three leaflets is relatively small, the opening  15   a  is smaller and the outer edge surfaces  15   b  of the leaflets abut one another. In  FIG. 3C , it can be seen that the radius of each leaflet is larger which results in a correspondingly larger opening  15   a  and a relatively smaller length of the outer edge surface that abuts an adjacent leaftlet. 
   Importantly, the arcuate structure of the leaflets, together with their elasticity, act to automatically center a fastener between the leaflets while also urging the fastener head against a driver bit. Moreover, and particularly for those structures where the leaflets minimize the space  15   a  as shown in  FIGS. 3A and 3B , the FRS can be effectively used with a wide range of fastener head diameters and fastener shaft diameters. That is, a single FRS can be used with fastener heads ranging for example, from ½ inch diameter down to a ⅛ th  inch diameter. Accordingly, and particularly when the FRS is used with a screwdriver having interchangeable bits, a single FRS can be used with a number of different size screwdriver bits ranging from larger size bits down to very fine or smaller bits. 
   As best shown in  FIGS. 5 and 7 , it is also preferred that the distal surface  14   b  of the lower section is outwardly tapered so as to provide a volume  18  for each leaflet to fold into as the a fastener head is passing through the leaflets during fastening. As shown in  FIG. 7 , a leaflet  15  may be folded into the volume  18  allowing the fastener head to pass through the leaflets without pinching the leaflets against a work surface. It is preferred that the vertical distance X between the underside of a leaflet  15  and the surface  14   a  is greater than the horizontal length Y of the leaflet. 
   It should be noted that the preferred number of leaflets is three. Other odd-numbered fastener retaining systems may be manufactured and provide the same centering properties of a three-leafed system. For example, five and seven leaflet systems are potentially practical embodiments. Systems with an even number of leaves will also work but are not preferred as the origin of various pairs of leaves and the central axis of the FRS will be aligned which may minimize the effectiveness of the system in providing the automatic centering functionality. 
   Sleeve  12   
   In a preferred embodiment, as best shown in  FIGS. 2 ,  3  and  6 , the sleeve  12  has a generally triangular cross section. The triangular cross section allows a single size fastener retaining system  10  to be used on a variety of driver diameters and cross-sections. With reference to  FIG. 6 , the sleeve is shown to include three inner surfaces  20 . It is preferred that surfaces  20  are inwardly convex so as to permit the sleeve  12  to engage with both smaller diameter driver shafts where the sleeve remains inwardly convex as well as larger diameter shafts where, due to the elasticity of the sleeve, will expand outwardly so that the surfaces  20  become outwardly concave (not shown). Furthermore, by virtue of this design, the inwardly convex surfaces will effectively engage with shafts having a non-circular cross-section. 
   In particular, for drivers having a hexagonal cross-section, the FRS will effectively enable that each of the surfaces  20  will be engaged against three of the flat surfaces of the hexagonal shaft driver (shown schematically in dotted lines in  FIG. 6 ) thus effectively preventing twisting of the sleeve around the hexagonal shaft. 
   Use 
   The FRS is most useful when a user either has a single or limited number of fastening jobs to complete within a confined or awkward space where the use of two hands to initiate the fastening process is difficult. For example, if a user is working within a confined space and cannot hold a fastener in one hand against the work surface while connecting the driver to the fastener, the FRS is particularly useful. In this scenario, a user would place the sleeve  12  over the shaft of the driver and position the FRS at the appropriate location along the shaft as described above. The fastener  5  would be inserted through the leaflets within the lower section and adjusted such that the fastener is retained against the bit surface. The user is then able to confidently use one hand to properly locate the fastener against the work surface, apply the fastening pressure and complete the fastening process. 
   In repeated use, where a user wishes to complete a larger number of fastenings using an identical fastener, after initially setting up the sleeve  10  in its proper position, the user can confidently complete each successive fastening while quickly and easily inserting a new fastener into the lower sleeve as each fastening is completed. 
   As the fastening process proceeds, the head of the fastener will begin to engage against the work surface. Due to the flexible and elastic nature of the lower sleeve and leaflets, as well as the tapering surfaces  14   b  of a typical fastener head as shown in  FIGS. 1 ,  5  and  7 , the leaflets will open and fold towards the work surface without pinching against the work surface. As the leaflets are cleared from the fastener head and the fastening process continues, the fastener will become fully engaged and/or countersunk against/within the work surface without damage to the leaflets. 
   However, it should be noted that over time, particularly with the use of electric drivers, the lower edge of the FRS may be worn out as a result of friction with the work surface. However, the FRS can be readily replaced with a new FRS. Naturally, the nature of the work surface will contribute to the longevity of a particular FRS where smoother surfaces where the abrasive forces are less will contribute to a longer life for a particular FRS. 
   The FRS may also be used in removing fasteners from work surfaces particularly where there is a risk of dropping the fastener as it is removed from the work surface. In this case, the above steps are performed in reverse with the result that when the fastener head has been withdrawn a distance sufficient to allow the leaflets to engage the fastener head, the leaflets will automatically “pop-over” and engage with the head so that by continued turning and eventual disconnection of the fastener with the work surface the leaflets retains the fastener. 
   Materials and Manufacture 
   The sleeve may be fabricated from polymeric materials having a range of properties. Typically, the sleeve will be manufactured in an injection molding process from any suitable elastic polymeric material such as but not being limited to nylons, rubbers, PVCs and polyurethanes that allow the sleeve to perform the desired functions of gripping both the shaft and fastener. In one embodiment the sleeve is a clear or partially clear silicone polymer so as to allow the user to observe the positioning and degree of engagement between the fastener head and the bit during both initial set up and repeated use. Durometer values of 60-80 are particularly beneficial 
   The polymeric material may also be manufactured with luminescence which may assist in illuminating a dark work area or be colour coded or imprinted with a symbol(s) to allow a user to quickly identify a driver type. 
   Further Embodiments 
   In a still further embodiment, the driver may be modified to allow the storage of a FRS within the head of the driver. With reference to  FIG. 8 , a typical driver head  30  is shown having a recess  32  for allowing the FRS to be withdrawn up the shaft and stored fully or partially within the driver head. In this embodiment, a user may push the FRS  10  up into recess  32  when the FRS is not required and then withdraw the sleeve from the recess by grasping a small protruding portion of the sleeve to slide the sleeve down the shaft  11   a  for use. 
   The FRS has been tested and found to be effective with a wide range of fastener types and head styles including PHILLIPS™, TORQ-SET™, TORX™, TORX PLUS™, TRI-WING™, hex, hex external, 12 pt (internal), 12 pt (external), Slotted, ROBERTSON™, clutch, POSIDRIVE™, TEKS™, FLORTORX™, TENSILOK™, Decorative Knurl, Tri-Angle, ROBERTSON™/Slotted, PHILLIPS™ (External Hex), Drilled Head, OPSIT, Truss, Binding, Fillistar, Oval, Round, Flat, Pan, Washer, Cheese, Cap, Button, Thumbscrew and Set-Screw Fasteners. 
   Further still, the FRS is effective in holding female style fasteners including nuts, caps, hex, bubble, serrated, pal, square, sleeve, barrel, MS, twist-off collars and TAMPRUF fasteners. In addition, the FRS is effective with sockets and can be particularly useful in holding both a washer and nut within a socket before tightening over a bolt. 
   As well, hose-clamps can be held positioned and tightened with the sleeve effectively holding the clamp for the procedure. 
   The above-described embodiments of the present invention are intended to be examples only. Alterations, modifications and variations may be effected to the particular embodiments by those of skill in the art.