Patent Publication Number: US-9415495-B1

Title: Nail remover tool with sliding fulcrum and dimple

Description:
BACKGROUND 
     The field of the invention relates to tools for removing embedded nails. In particular, the field of the invention relates to tools for removing an embedded nail from a substrate and minimizing damage to the substrate and embedded nail as the nail is removed so that the substrate and nail may be further repurposed or recycled. 
     Nail remover tools or nail pullers are known in the art. (See, e.g., U.S. Pat. Nos. 8,904,585; 8,517,340; 7,252,021; 7,051,390; 7,036,952; 6,923,432; 6,629,684; 6,605,576; 6,578,820; 6,519,858; 6,308,934; 6,266,834; 5,896,607; 5,800,021; 5,749,113; 5,575,029; 5,695,172; 5,141,205; 5,099,724; 4,482,131; 1,486,820; and U.S. Published Application Nos. 2015/0028273; 2013/0283541; 2012/0138879; 2012/0098282; 2011/0314971; 2011/0088170; 2010/0263133; 2010/0038608; 2009/0165607; 2009/0145938; 2009/0114891; 2008/0134846; 2007/0039286; 2006/0191378; 2006/0156685; 2005/0062026; 2005/0172415; and 2004/0174700; the contents of which are incorporated herein by reference in their entireties). However, many nail remover tools currently in use require a large amount of force in order to remove an embedded nail from a substrate, such as wood, and may cause unnecessary damage to the substrate and nail as the nail is removed. Nail removers that require a lower amount of force and that may be used to remove an embedded nail from a substrate while minimizing damage to the substrate and nail are desirable. 
     SUMMARY 
     Disclosed is a novel nail remover tool that requires lower force to remove an embedded nail from a substrate than nail remover tools currently in use. The disclosed nail remover tool minimizes damage to the substrate and nail as the nail is being removed from the substrate. 
     The disclosed nail remover tool requires lower force because the tool is structured to utilize a sliding fulcrum feature as force is applied to the tool in order to remove a nail. The disclosed nail remover also minimizes damage to the structure because the tool utilizes a dimple feature. These features and other features of the novel nail remover tool are disclosed further herein. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates a perspective view of one embodiment of a nail remover tool as contemplated herein. 
         FIG. 2  illustrates another perspective view of one embodiment of a nail remover tool as contemplated herein. 
         FIG. 3  illustrates a top view of one embodiment of a nail remover tool as contemplated herein. 
         FIG. 4  illustrates a left side view of one embodiment of a nail remover tool as contemplated herein. 
         FIG. 5  illustrates a left side perspective view a nail remover tool being aligned over a nail head. 
         FIG. 6  illustrates a left side perspective view of the nail remover tool of  FIG. 5  being used to indent a substrate around the head of a nail by applying force to the tool. 
         FIG. 7  illustrates a perspective view of the nail remover tool of  FIG. 6  being removed after having being used to indent a substrate around the head of a nail. 
         FIG. 8  illustrates a perspective view of the nail remover tool of  FIG. 7  being used to engage the nail by the toothed claw of the tool via applying force to the tool. 
         FIG. 9  illustrates a perspective view of the nail remover tool of  FIG. 8  having rotational force being applied to the tool in order to remove the engaged nail. 
         FIG. 10  illustrates the mechanics of a nail remover tool as contemplated herein including the defined effort arm, defined initial fulcrum point, and defined load arm. 
         FIG. 11  provides a story board of a nail remover tool as contemplated herein being used to remove a nail and illustrates the concept of a sliding fulcrum and decreasing load arm as discussed herein. 
         FIG. 12  illustrates average measured damage area versus nail puller type. 
         FIG. 13  illustrates before and after photos of damage cause by the Vaughn Nail Puller Bar. 
         FIG. 14  illustrates average subjective damage rating versus nail puller type. 
         FIG. 15  illustrates average human force exertion versus nail height for the Vaughn Nail Puller Bar. 
         FIG. 16  illustrates average human force exertion versus nail height for the Stanley Precision Claw Bar. 
         FIG. 17  illustrates average human force exertion versus nail height for our tested model nail removal tool. 
     
    
    
     DETAILED DESCRIPTION 
     The subject matter disclosed herein is described using several definitions, as set forth below and throughout the application. 
     Unless otherwise specified or indicated by context, the terms “a,” “an,” and “the,” mean “one or more.” For example, “a surface” should be interpreted to mean “one or more surfaces.” 
     As used herein, “about,” “approximately,” “substantially,” and “significantly” will be understood by persons of ordinary skill in the art and will vary to some extent on the context in which they are used. If there are uses of these terms which are not clear to persons of ordinary skill in the art given the context in which they are used, “about” and “approximately” will mean plus or minus ≦10% of the particular term and “substantially” and “significantly” will mean plus or minus &gt;10% of the particular term. 
     As used herein, the terms “include” and “including” have the same meaning as the terms “comprise” and “comprising.” The terms “comprise” and “comprising” should be interpreted as being “open” transitional terms that permit the inclusion of additional components further to those components recited in the claims. The terms “consist” and “consisting of” should be interpreted as being “closed” transitional terms that do not permit the inclusion of additional components other than the components recited in the claims. The term “consisting essentially of” should be interpreted to be partially closed and allowing the inclusion only of additional components that do not fundamentally alter the nature of the subject matter recited in the claims. 
     As used herein, the phrase “nail remover tool,” which may alternatively be referred to as “nail puller tool,” refers to a tool utilized for removing an embedded nail from a substrate. Typically, an “embedded nail in a substrate” refers to a metal nail that has been driven into a wood or composite substrate. 
     The disclosed nail remover tool may be described as follows. In some embodiments, the disclosed nail remover tool may be described as including a shaft having a handle end and a head end. Typically, the handle end is utilized for grasping the tool and applying force (e.g., human pulling and/or pushing force). The head end is attached to a head that is utilized to engage and remove a nail embedded in a substrate. 
     The head of the tool typically includes or is defined by (a) a left side surface; (b) a right side surface; where optionally the left side surface and the right side surface are substantially parallel to each other; and (c) radial surfaces that transverse a perimeter portion of the left side surface of the head and a perimeter portion of the right side surface of the head. As such, the radial surfaces of the head are present on a radial surface of the head transversing the perimeter portion of the left side surface and the perimeter portion of the right side surface. 
     The radial surfaces typically include (i) a first striking surface, which preferably is substantially flat and optionally includes a hatch pattern to indicate that the surface is for striking; (ii) a dimpling surface opposite to the first striking surface, the dimpling surface comprising a dimple, such that when the first striking surface is struck, force is applied at the dimple, and the dimpling surface may be used to create an indentation in a substrate in a perimeter around the nail head of an embedded nail in order to expose the nail head and preferably the nail stem; (iii) a top claw surface and a bottom claw surface that form a toothed claw between the first striking surface and the dimpling surface; and (iv) a second striking surface opposite the toothed claw, such that when force is applied at the second striking surface, force is applied at the toothed claw to the nail. 
     The shaft of the tool extends linearly from the head of the tool. Typically, the shaft of the tool extends linearly in a direction from the second striking surface opposite the toothed claw. For example, a surface of the shaft and the second striking surface may be in the same plane or in parallel planes where the surface of the shaft extends linearly from the head of the tool. 
     The dimple of the tool is configured for creating an indentation in a substrate in which a nail has been embedded. In use, the dimple is placed over the nail head of a nail and the first striking surface is struck causing an indentation in the substrate in a perimeter around the nail head and optionally causing the nail head and preferably the nail stem to be exposed above the surface of the substrate. Exposed as such, the nail head and preferably the nail stem may be more readily engaged by the teeth of the toothed claw of the device. In order to facilitate alignment of the dimple and the nail head prior to creating the indentation, the left side surface of the head and/or the right side surface of the head may include an indication that is utilized to align the dimple and the nail head. For example, suitable alignment indications may include a groove in the left side surface of the head and/or a groove in the right side surface that is in alignment with the dimple, although any marking which may be used as an indicator of alignment may be utilized. 
     The dimple includes a recess for receiving a nail head and a protruding rim surrounding the dimple for creating an indentation in a substrate in which the nail has been embedded (i.e., an indentation in the substrate around a perimeter of the nail head). The dimple may be permanently attached to the head of the tool, for example, where the dimple and the head form a unitary structure. Alternatively, the dimple may be removable, for example where the dimple is screwed into a receptacle at the dimpling surface of the head of the tool, or the dimple is otherwise removably attached to the dimpling surface of the head of the tool. In some embodiments of the disclosed nail remover tools, the dimple may be removably attached to head of the tool and may be replaceable by dimples having different sized recesses, for example dimples having smaller or larger recesses for receiving smaller or larger nail heads. As such, the dimple may be gauged for use in removing particular nail heads (i.e., where a small gauge dimple is used to remove a small gauge nail) in order to minimize any damage by creating the smallest perimeter indentation about the nail head that is required for exposing the nail head. 
     The tool also includes a toothed claw at the head of the tool that includes two teeth with a space therebetween for receiving a nail head and nail stem. In use, after the dimple of the tool has been used to create an indentation in a substrate in which a nail is embedded and expose the nail head and nail stem, the teeth of the toothed claw may be positioned about the nail stem. Then, the second striking surface opposite the toothed claw may be struck to force the nail stem in between the space between the teeth and engage the nail head and nail stem. Optionally, the teeth may have substantially semicircular recesses on their top surfaces for receiving the nail head as the second striking surface is struck and the nail stem is forced into the space between the teeth and nail head and nail stem are engaged by the toothed claw. These semicircular recesses may be otherwise referred to as “nail grip slots” and the nail head may become seated in the nail grip slot as the nail stem and nail head are forced between the teeth of the toothed claw. 
     The disclosed tool typically includes a toothed claw at the head of the tool. Optionally, the disclosed tool may further include a toothed claw at the handle end of the shaft. The toothed claw at the handle end of the shaft may be configured on the tool to facilitate removal of nails that are embedded in tight spaces, such as room corners or otherwise. For example, the toothed claw at the handle end of the shaft may be in a position that is rotated about the shaft (e.g., approximately 30°, 45°, 60°, 75°, 90°, 105°, 120°, 135°, or 150°) relative to the position of the toothed claw at the head of the shaft, in order to permit the toothed claw at the handle end to be positioned around a nail in a tight space. 
     When the tool includes an optional toothed claw at the handle end of the shaft, the tool may include a third striking surface at the head of the device for applying force at the toothed claw at the handle end of the shaft when the third striking surface at the head of the tool is struck. The third striking surface may be located at the head of the tool between the dimpling surface and the toothed claw of the head for applying force at the toothed claw of the handle end of the shaft when the third striking surface is struck. Optionally, the third striking surface may be substantially flat and may include a hatch pattern indicating that the surface is for striking. 
     The optional toothed claw at the handle end of the shaft may be similarly configured as the toothed claw at the head end of the shaft. For example, the toothed claw at the handle of the shaft may include two teeth with a space therebetween for receiving a nail stem and nail head. The teeth of the toothed claw at the handle end of the shaft may be positioned on either side of the nail stem. Then, the third striking surface may be struck to force the nail stem in between the space between the teeth and engage the nail head and nail stem. Optionally, the teeth may have substantially semicircular recesses on their top surfaces for receiving the nail head as the third striking surface is struck and the nail stem is forced into the space between the teeth and the nail head and nail stem are engaged by the toothed claw at the handle end of the shaft. As discussed herein, these semicircular recesses may be otherwise referred to as “nail grip slots” and the nail head may become seated in the nail grip slot as the nail stem and nail head are forced between the teeth of the toothed claw. Force then may be applied to the tool at the head of the shaft and transmitted to the handle end of the shaft in order to remove the nail. 
     Optionally, the disclosed tool may include a leveling device inserted in the shaft of the tool. Suitable leveling devices may include bubble levels or spirit levels. In some embodiments, the disclosed tool is designed to sit flat and have a top surface into which the leveling device is inserted. Optionally, the disclosed tool may be designed to sit flat on one or more surfaces, including but not limited to a surface present at the head of the tool (e.g., the second striking surface), a surface of the shaft (e.g., a bottom surface opposite a top surface into which the leveling device is inserted), and a surface of the optional toothed claw at the handle of the shaft. 
     The disclosed tool may be utilized for removing an embedded nail in a substrate by a method that includes: (a) aligning the tool with the dimple of the tool over the nail, (b) striking the first striking surface of the head of the tool to form an indentation in the substrate and expose the nail head and/or nail stem, (c) placing the toothed claw of the head of the tool around the nail, (d) striking the second striking surface of the head of the tool (e.g., to force the nail stem into the space between the teeth and optionally to seat the nail head in the optional substantially semicircular recesses on the top surface of the teeth), and (d) applying levered force (i.e. human exertion) upwardly and then downwardly from the handle end of the shaft towards the toothed claw until the embedded nail is removed. The upwardly and downwardly human exertion force provides a force that is perpendicular to the tool shaft throughout the range of movement of the tool shaft. In mechanical terms, a force applied perpendicular to the tool shaft along with the distance to the fulcrum (L effort ) is considered the leverage of the tool. Because the dimple and the toothed claw both are placed on the radius of the head geometry (i.e., instead of on the side of the head), a user need not change his/her hand grip when using the disclosed tool (i.e., between steps (b) and (d)). 
     In addition to being configured to minimize damage to a substrate and a nail embedded in a substrate when the embedded nail is removed from the substrate, the disclosed tools also are configured to minimize the force required to remove the embedded nail from the substrate. As described below, the tool is configured to engage an embedded nail at an optimal angle for removing the embedded nail and to utilize a sliding fulcrum feature in order to minimize the force required to remove an embedded nail throughout all movement steps. 
     In the disclosed nail remover tools, the angle of the shaft when a nail is engaged by the toothed claw is an optimal angle for obtaining maximum upward force at the toothed claw when rotation force is applied upwardly at the handle end of the tool. For example, when the toothed claw engages a nail embedded in a substrate, the bottom surface of the toothed claw contacts the top surface of the substrate and the shaft of the tool extends at an angle from the head of the tool. As such, the bottom surface of the toothed claw and the shaft can be described as forming an angle α, and preferably, in order to obtain maximum upward force at the toothed claw when rotation force is applied upwardly at the handle end of the tool, 50°&lt;α&lt;70°. 
     In some embodiments of the disclosed nail remover tools, after the embedded nail has been engaged by the toothed claw, the tool may be used as a lever in order to remove the nail with a mechanical advantage by applying rotation force at the handle of the tool. As rotation force is applied at the handle end of the tool, the initial fulcrum of the level slides forward and increases the mechanical advantage of the level as the rotational force is applied which is discussed further below. 
     Referring now to the figures,  FIGS. 1 and 2  illustrate perspective views of embodiments of a nail remover tool  2  as contemplated herein.  FIGS. 3 and 4  illustrate a top view and a left side view of embodiments of a nail remover tool  2  as contemplated herein. The tool  2  includes a shaft  4  having a handle end  6  and a head end  8 , and a head  10  attached at the head end  8  of the shaft  4 . The head  10  includes: (a) a left side surface  12 ; (b) a right side surface  14 , and (c) radial surfaces that transverse a perimeter portion of the left side surface and a perimeter portion of the right side surface. The radial surfaces include: (i) a first striking surface  16 , (ii) a dimpling surface  18  opposite to the first striking surface  16 , the dimpling surface comprising a dimple  20 ; (iii) a top claw surface  22  and a bottom claw surface  24  forming a toothed claw  26  between the first striking surface  16  and the dimpling surface  18 , the toothed claw having two teeth  26   a , 26   b  with a space therebetween for receiving a nail stem; and (iv) a second striking surface opposite the toothed claw  28 . The shaft  4  of the tool  2  extends linearly from the second striking surface  28  opposite the toothed claw  28 . As illustrated, the left side surface  12  and the right side surface  14  include a grooved indication  30  in alignment with the dimple  20  for aligning the dimple with a nail head. 
     As indicated in  FIG. 2 , the dimple  20  comprises a substantially circular recess  20   a  defined by a protruding substantially circular rim  20   b . The recess  20   b  is configured for receiving a nail head and the protruding rim  20   a  is configured for forming an indentation around the nail head when the dimple is positioned over the nail head and the first striking surface  16  of the tool is struck. 
     As illustrated in  FIGS. 1-4 , the tool  2  further comprises a toothed claw at the handle end of the shaft  32 . As illustrated, (see particularly in  FIG. 3 ), the toothed claw at the handle end of the shaft  32  is in a position that rotated about the shaft  4  approximately 90° relative to the position of the toothed claw at the head of the shaft  26 . Also as illustrated, the head of the tool  10  further comprises a third striking surface  34  between the dimpling surface  18  and the toothed claw  26  for striking and applying force at the toothed claw of the handle end of the shaft  32  when the third striking surface  34  is struck. The toothed claw of the handle end of the shaft  32  comprises two teeth  32   a , 32   b  with a space therebetween for receiving a nail stem. 
     As illustrated in  FIGS. 1 and 3 , the tool includes a leveling device  36  inserted in the shaft of the tool  4 . As illustrated in  FIG. 3 , the leveling device  36  is inserted in the shaft  4  on a side of the shaft (i.e., the top side of the shaft  4   a ) that is opposite the second striking surface of the head  28  and the tool lays flat when the second striking surface  28  is placed downward. 
     The shaft of the contemplated tool may be configured to provide an optimal mechanical advantage when removing a nail. As illustrated in  FIG. 4 , the shaft  4  and the bottom surface of the toothed claw  24  form an angle α, where preferably 50°&lt;α&lt;70°. 
       FIGS. 5-9  illustrate embodiments of the tool in use. As illustrated in  FIG. 5 , the head of the tool is aligned with a nail  40  embedded in a substrate  42  via use of alignment indicator  30  to position the dimple  20  of the tool over the embedded nail  40 . Next, as illustrated in  FIGS. 6 and 7 , the first striking surface  16  is struck to form an indentation  44  in the substrate  42  and expose the head of the nail  40  and nail stem in the substrate  42  for access by the toothed claw  26 . The nail head may be above, below, or at the initial substrate surface level after the indention  44  by the dimple  20 . Next, as illustrated in  FIG. 8 , the toothed claw of the head of the tool  26  is positioned with its teeth  26   a , 26   b  around the nail  40  and the second striking surface of the head of the tool  28  is struck to force the stem of the nail into the space between the teeth  26   a , 26   b  and to seat the nail head in the substantially semicircular recesses on the top surface of the teeth  27 . Finally, as illustrated in  FIG. 9 , rotational force is applied upwardly then downwardly from the shaft  4  towards the toothed claw  26  until the embedded nail  40  is removed. 
       FIGS. 10 and 11  illustrate the mechanics applied to the tool in order to remove a nail. The disclosed nail remover tool effectively may be used as a lever to remove a nail. As illustrated in  FIG. 10 , the length of the load arm of the lever L load  is the distance between the nail N and the fulcrum point of the lever F. The length of the effort arm L effort  of the lever is the distance between the point at which the force is applied at the handle end of the shaft and the fulcrum point F. The mechanical advantage given by the device in removing a nail is proportional to the length of the effort arm divided by the length of the load arm (i.e., L effort /L load ). 
     As illustrated in  FIG. 11( a )-( g ) , as rotation force is applied at the handle end of the shaft, first upwardly then downwardly, the initial fulcrum F slides closer to the nail N. Initially, the fulcrum F is located at the junction between the bottom claw surface  24  and the third striking surface  34 . (See  FIG. 11( a ) ). As rotational force is applied upwardly at the handle of the tool, the fulcrum F slides to the center of the third striking surface  34 . (See Figures (b) and (c)). The tool rests upright when sitting on the third striking surface  34 . (See Figure (c)). As rotational force next is applied downwardly at the handle of the tool, the fulcrum F slides to the center of the dimpling surface  18 . (See Figures (d)-(f)). As the final rotation force is applied prior to the nail being removed from the substrate, the fulcrum F slides to the juncture of the dimpling surface  18  and the second striking surface  28 . (See Figure (g)). The sliding motion of the fulcrum throughout these nail removing movements reduces the length of the load arm L as the rotation force is applied at the handle of the tool. (See Figures (a)-(g)). Hence, the sliding motion of the fulcrum F increases the mechanical advantage as the rotation force is applied at the handle of the tool where the mechanical advantage of the tool is proportional to L effort /L load  and L load  decreases throughout the nail removing movements. 
     For nail removers currently in use which do not utilize a sliding fulcrum during the nail removing movements, the nail may become excessively bent, which damages the nail and increases the amount of force (i.e., human exertion) required to remove the nail at the end of the nail removing movement because of friction between the bent nail and the substrate. In comparison, the disclosed nail remover tool is advantageous in that as the fulcrum slides towards the nail during the nail removing movement, bending of the nail is reduced, so that damage to the nail is minimized and increased force is not required at the end of the nail removing movement to remove the nail. (See  FIGS. 11( a )-( g ) ). 
     EXAMPLES 
     The following examples are illustrative and are not intended to limit the scope of the claimed subject matter. 
     We have developed a novel nail remover tool. The base head of the tool has a unique geometry and dimple feature that makes it a more ergonomic design and allows the user to remove nails from plywood, sheathing, underlayment, and other similar substrates with ease and with minimal destruction to the substrates. 
     The nail removal tool has at least five features that provide advantages: an ergonomic head geometry, a dimple having an advantageous location with respect to its orientation on the ergonomic head, a dimple sight alignment, nail grip slots on the teeth of the toothed claw that allow a nail head to be gripped more easily during nail removal, and a length of approximately 14.5″. 
     The ergonomic head has a fulcrum point that allows better mechanical advantage for the user. As a user applies rotational force to the tool after engaging a nail, the fulcrum point slides forward to reduce the length of the load arm and provide an increased mechanical advantage. 
     On the ergonomic head, there is a dimple that fits around a nail such as an 8 or 16 penny nail and other similar fasteners that reduces the amount of damage to the surface the nail is in when compared to the common nail removers used for similar purposes. The position and orientation of the dimple on a radial surface of the head makes it possible for a user to use the dimple feature and the toothed claw feature without the user having to change hand positions to remove a nail from start to finish. 
     The dimple will have threads to attach to the tool&#39;s head and be able to be replaced after dulling occurs. The dimple will come in many different sizes that range in the diameter for the various nail head sizes. A common screw driver, hex key, or other hand tool may be used to remove and replace the dimple. A striking force is applied to the face of the head that is 45 degrees to the shaft that causes a displacement of the area in the surface around the nail that the face of the dimple contacts. The dimple sight alignment allows the user to visually track the position of the dimple in comparison to the nail and surface surrounding the nail. 
     The tool also includes a nail grip slot on the teeth of the claw head that allow a nail head to be gripped more easily. As a nail is driven between the teeth of the toothed claw of the tool, the nail head becomes seated in the nail grip slot, which makes it less likely that the nail will slip from the teeth as the nail is being removed. 
     Finally, the tool has a length of 14.5″. Because the distance between joists and studs commonly is 16,″ the length of 14.5″ permits the tool to fit between 16″ on center joists or studs made of material (e.g., 2× wood) that is 1.5″ thick. 
     Damage Testing and Force Testing 
     We tested our nail remover tool against two other nail remover tools including the Stanley Precision Claw Bar and the Vaughn Nail Puller Bar. In particular, we performed damage testing and force testing. 
     Damage testing was performed by painting a black 2 inch by 2 inch square around each nail. Then the three different nail removers were used to remove the nail and the results were analyzed both quantitatively and qualitatively. The quantitative results were done by having 4 people measure the area that was damaged. The data were analyzed as a two factor experiment in respect to the tool used and the person measuring. The quantitative results showed that the our tested nail remover tool caused 29% less damage than the Vaughn Nail Puller Bar and 18% less damage than the Stanley Precision Claw Bar.  FIG. 12  shows the average damage area measured and the standard deviations. The ANOVA analysis showed that our tested nail remover tool was significantly different than both the Stanley Precision Claw Bar and Vaughn Nail Puller Bar (p≦0.05). 
     After quantitatively analyzing the damage results, we performed a survey using before and alter pictures and 41 randomly selected people from the general population. An example of the before and after picture from the survey is shown in  FIG. 13  and the results of the survey are shown in  FIG. 14 . The ANOVA of the survey data showed that there was no visual difference of damage between our tested nail remover tool and the Stanley Precision Claw Bar (p≧0.05) with means of 3.13 and 3.34, respectively, but there was a visual difference of damage between our tested nail remover tool and the Vaughn Nail Puller Bar (p≦0.05) with means of 3.13 and 3.87, respectively. (See  FIG. 14 ). The data were analyzed as a two factor experiment in respect to the tool used and the surveyor. 
     Human force testing was performed by measuring the horizontal pulling force on the tools shaft throughout the entire motion of the removal process. The data were then plotted and analyzed using a one factor experimental design at each nail height that the data were taken.  FIG. 15 ,  FIG. 16 , and  FIG. 17  shows the data collected from the Vaughn Nail Puller Bar, Stanley Precision Claw Bar, and our tested nail remover tool respectively. The maximum and minimum values were computed using a 95% confidence interval. An ANOVA with α=0.05 showed at an exposed nail height of 1.5″ our tested nail remover tool requires 24% less force than the Stanley Precision Claw Bar with means of 40.9 lbf and 54.0 lbf respectively. These data illustrate that our tested nail remover tool requires less human force applied on the shaft of the tool in order to remove a nail. 
     It will be readily apparent to one skilled in the art that varying substitutions and modifications may be made to the invention disclosed herein without departing from the scope and spirit of the invention. The invention illustratively described herein suitably may be practiced in the absence of any element or elements, limitation or limitations which is not specifically disclosed herein. The terms and expressions which have been employed are used as terms of description and not of limitation, and there is no intention in the use of such terms and expressions of excluding any equivalents of the features shown and described or portions thereof, but it is recognized that various modifications are possible within the scope of the invention. Thus, it should be understood that although the present invention has been illustrated by specific embodiments and optional features, modification and/or variation of the concepts herein disclosed may be resorted to by those skilled in the art, and that such modifications and variations are considered to be within the scope of this invention. 
     Citations to a number of patent and non-patent references are made herein. The cited references are incorporated by reference herein in their entireties. In the event that there is an inconsistency between a definition of a term in the specification as compared to a definition of the term in a cited reference, the term should be interpreted based on the definition in the specification.