Abstract:
A method of and device for picking up ferrous debris off of a walking surface in a work area provides a way for workers to passively help maintain the work area and keep it free from the debris. Workers wear magnetic footwear onto the walking surface. A magnet is inserted or affixed in any recessed portion of a sole of the footwear such that a receptacle is created in the bottom of the sole to which any metallic debris that is capable of being magnetized can be attracted and retained as the workers move around the walking surface. The footwear can then be cleaned when the workers leave the work area, either by cleaning the debris from the magnet or removing some part that has retained the debris with its magnetic attraction.

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
       [0001]    This application is a continuation-in-part of Ser. No. 11/657325, filed Jan. 24, 2007 entitled “Foot Covering for Collecting Debris.” 
     
    
     BACKGROUND 
       [0002]    The invention relates to an article of footwear such as a boot, shoe, sneaker, clog, or sandal, and more specifically to an article of footwear including a magnet for collecting ferrous debris from a walking surface. 
         [0003]    In certain industrial environments, where machining, assembly or disassembly occurs, the walking surfaces tend to accumulate foreign objects or debris. The debris is often made up of small fasteners such as nuts, bolts, screws, nails or machining shavings or chips. The debris is a safety hazard to workers, and is attributable to puncture, cut, slip and fall injuries. 
         [0004]    Product quality is also negatively impacted by foreign object damage, also known as (FOD). Foreign objects enter the product during assembly and can cause quality defects such as operational malfunction or complete product failure. The potential consequences of these quality defects may be loss of a customer, loss of a house by fire, or in the case of a carrier launched jet fighter, loss of the aircraft. As can be seen by the preceding examples, FOD presents a clear and present danger, and must be eliminated from industrial environments. 
         [0005]    For various reasons, fasteners are typically made of ferrous alloys that include iron. Design constraints such as thread strength, corrosion resistance and cost, make ferrous fasteners ideal for many assembly applications. Because of their attraction to magnetic fields, the use of magnets can facilitate the collection of ferrous-material debris. 
         [0006]    Magnetic sweeping devices, such as those disclosed in Conrad et al. U.S. Pat. No. 5,979,957, Haase et al. U.S. Pat. No. 6,142,310 and Ottens U.S. Pat. No. 6,669,024, require active interaction by a worker. A worker moves the sweeper device about a surface to collect ferrous debris as an additional activity during the workday. Because these sweeping devices require active interaction, an additional worker must be hired or a skilled worker must be utilized to sweep the walking surface for ferrous debris. 
         [0007]    Magnetic insoles, such as those disclosed in Humphreys U.S. Pat. No. 5,233,768, Greenawalt U.S. Pat. No. 5,976,100, Qui, et al. U.S. Pat. No. 6,151,807 and Bove et al. U.S. Pat. No. 6,322,491, are utilized for therapeutic purposes. The magnets are imbedded into a sole or insole of a shoe to ensure they are in close proximity to the foot. The associated magnetic fields dilate the blood vessels, providing increased blood circulation in the foot. Because of the close proximity to the foot and insulative properties of the soles, the magnetic force does not extend to the walking surface. 
         [0008]    What is desirable is a magnetic device for passively collecting ferrous debris from a walking surface throughout the day. The elimination of debris from the walking surface will improve worker safety, enhance product quality and improve customer satisfaction. 
       SUMMARY 
       [0009]    In accordance with the present invention, an article of footwear for collecting ferrous debris from a surface is provided. A magnet can be disposed in any portion of a sole that is recessed and spaced from the surface when the sole touches the surface. In one embodiment, the magnet can be disposed in an arch portion of the sole, between the toe and heel portions. In another embodiment, the magnet can be disposed within indentations created by a tread on the sole. In both embodiments, the magnet is at least partially exposed to the surface and is spaced from the surface. The space between the magnet and the surface allows ferrous debris to accumulate, without causing a safety hazard. 
         [0010]    A primary advantage of the present invention is the ability to easily collect ferrous objects throughout the workday, without the need for a separate sweeping activity. When all workers in a facility wear the inventive footwear, the walking surface is continuously swept of ferrous debris as the workers walk about. 
         [0011]    These and other objects, features and advantages of the present invention will become apparent in view of the following detailed description and accompanying figures of multiple embodiments, where corresponding identifiers represent like features between the various figures. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]      FIG. 1  is a side view, illustrating an article of footwear according to an embodiment of the present invention; 
           [0013]      FIG. 2  is a bottom view of the article of footwear of  FIG. 1  as viewed in the direction of line A-A; 
           [0014]      FIG. 3  is a sectional view of an embodiment of a sole of the article of footwear of  FIG. 1 , taken along line B-B, illustrating a magnet that is permanently attached to an arch surface; 
           [0015]      FIG. 4  is a sectional view of another embodiment of a sole of the article of footwear of  FIG. 1 , taken along line B-B, illustrating a magnet that is removable to an arch surface; 
           [0016]      FIG. 5  is a sectional view of yet another embodiment of a sole of the article of footwear of  FIG. 1 , taken along line B-B, illustrating a magnet that is permanently attached to an arch pocket, with a debris collection surface flush with an arch ceiling surface; 
           [0017]      FIG. 6  is a sectional view of yet another embodiment of a sole of the article of footwear of  FIG. 1 , taken along line B-B, illustrating a magnet that is removable from an arch pocket, with a debris collection surface flush with an arch ceiling surface; 
           [0018]      FIG. 7  is a sectional view of yet another an embodiment of a sole of the article of footwear of  FIG. 1 , taken along line B-B, illustrating a magnet that is permanently attached to an arch pocket, with a debris collection surface recessed below an arch ceiling surface; 
           [0019]      FIG. 8  is a sectional view of yet another embodiment of a sole of the article of footwear of  FIG. 1 , taken along line B-B, illustrating a magnet that is removable from an arch pocket, with a debris collection surface recessed below an arch ceiling surface; 
           [0020]      FIG. 9  is a sectional view of yet another embodiment of a sole of the article of footwear of  FIG. 1 , taken along line B-B, illustrating a magnet that is permanently attached to an arch pocket, with a debris collection surface extended beyond an arch ceiling surface; and 
           [0021]      FIG. 10  is a sectional view of yet another embodiment of a sole of the article of footwear of  FIG. 1 , taken along line B-B, illustrating a magnet that is removable from an arch pocket, with a debris collection surface extended beyond an arch ceiling surface. 
           [0022]      FIG. 11  is a perspective view of yet another embodiment of a sole of the article of footwear of  FIG. 1 , illustrating a magnet that can be inserted into the recesses of the sole created by a tread in both a toe and a heel portion of the sole. 
           [0023]      FIG. 12  is a perspective view of yet another embodiment of a sole of the article of footwear of  FIG. 1 , illustrating a magnet that can be inserted into the recesses of the sole created by a tread when no arch is present. 
           [0024]      FIG. 13  is a perspective view of yet another embodiment of a sole of the article of footwear of  FIG. 1 , illustrating multiple magnets that can be inserted into individual recesses of the sole created by tread. 
       
    
    
     DETAILED DESCRIPTION 
       [0025]    In  FIG. 1 , an article of footwear  20  includes an upper portion  22  and a sole  24  attached beneath the upper portion  22 . The upper portion  22  is typically made of a formable material such as leather, while the sole  24  is typically made of an insulating material such as molded urethane rubber. In the examples, the article of footwear  20  is illustrated as a work boot style, but a shoe, sneaker, clog, sandal or any other existing or created structure that can be worn on the foot would similarly benefit from the present invention. 
         [0026]    The sole  24  is divided into three lengthwise segments; a rearward heel  26 ; a forward toe  28 ; and a central arch  30  located between the heel  26  and toe  28 . An arch ceiling  32  is a surface that is raised from a walking surface S, providing an arch void  34  therebetween. Each of the heel  26  and toe  28  segments has a contact surface  36  that meets the walking surface S. In some embodiments, the arch segment  30  also contains a contact surface  36 . The contact surfaces  36  may be flat or they may contain tread  37  that creates recesses  39  in the sole  24  (as illustrated in  FIGS. 2 and 3 ) and is made of any number of raised patterns to improve traction and comfort. 
         [0027]    Further details of the sole  24  are illustrated in  FIG. 2 . One or more magnets  38  are attached to the sole  24  in the arch  30  segment. A magnet  38  is permanently attached or is removable from the sole  24  to provide periodic removal for cleaning of accumulated debris D and/or replacement of the magnet  38 . Although a round magnet  38  is illustrated, a magnet  38  may be rectangular, ring or polygon shaped to fit into the arch  30 . The magnet  38  material may be; Hard Ferrite; Flexible Ferrite; SmCo, Samarium Cobalt; NdFeB, Neodymium Iron Boron; AlNiCo, Alnico; or any other magnet  38  material known in the art. 
         [0028]    In  FIGS. 3-4 , an embodiment of an article of footwear  20  with an arch ceiling  32  mounted magnet  38  is illustrated. In the present embodiment, the magnet  38  is attached to the arch ceiling  32  with a majority of the magnet  38  exposed to the walking surface S. A collection surface  40  is raised above the walking surface S to allow debris D to accumulate on the collection surface  40  and around a periphery surface  42  without creating a tripping hazard. The collection surface  40  is raised from 0.635 cm to 2.54 cm (0.25 inch and 1.0 inch) above the walking surface S, and preferably is raised 0.635 cm to 1.27 cm (0.25 inch and 0.5 inch) above the walking surface S. The magnet  38  is permanently attached with an adhesive material  44  as illustrated in  FIG. 3 , or is removable as illustrated in  FIG. 4 . Removal means  46 , such as tabs, clips or other fasteners, attach the magnet  38  to the arch ceiling  32 , providing for periodic removal. Periodic removal of the magnet  38  allows for cleaning of accumulated debris D and/or magnet  38  replacement. 
         [0029]    In  FIGS. 5-6 , an embodiment of an article of footwear  20  with a pocket  48  mounted magnet  38  is illustrated. In the present embodiment, the magnet  38  is attached to a pocket  48  above the arch ceiling  32 . The collection surface  40  of the magnet  38  is approximately flush with the arch ceiling  32 , and only the collection surface  40  of the magnet  38  is exposed to the walking surface S. The collection surface  40  is raised above the walking surface S to allow debris D to accumulate on the collection surface  40  without creating a tripping hazard. The collection surface  40  is raised from 0.635 cm to 2.54 cm (0.25 inch and 1.0 inch) above the walking surface S, and preferably is raised 0.635 cm to 1.27 cm (0.25 inch and 0.5 inch) above the walking surface S. The magnet  38  is permanently attached with an adhesive material  44  as illustrated in  FIG. 5 , or is removable as illustrated in  FIG. 6 . Removal means  46 , such as tabs, clips or other fasteners, attach the magnet  38  to the arch ceiling  32 , providing for periodic removal. Periodic removal of the magnet  38  allows for cleaning of accumulated debris D and/or magnet  38  replacement. 
         [0030]    In  FIGS. 7-8 , an embodiment of an article of footwear  20  with a pocket  48  mounted magnet  38  is illustrated. In the present embodiment, the magnet  38  is attached to a pocket  48  in the arch segment  30 . Please note that the arch segment  30  contacts the walking surface S in this sole  24  embodiment. The collection surface  40  and portions of the periphery surface  42  of the magnet  38  are exposed to the walking surface S. The collection surface  40  is raised above the walking surface S to allow debris D to accumulate on the collection surface  40  without creating a tripping hazard. The collection surface  40  is raised from 0.635 cm to 2.54 cm (0.25 inch and 1.0 inch) above the walking surface S, and preferably is raised 0.635 cm to 1.27 cm (0.25 inch and 0.5 inch) above the walking surface S. The magnet  38  is permanently attached with an adhesive material  44  as illustrated in  FIG. 7 , or is removable as illustrated in  FIG. 8 . Removal means  46 , such as tabs, clips or other fasteners, attach the magnet  38  to the pocket  48 , providing for periodic removal. Periodic removal of the magnet  38  allows for cleaning of accumulated debris D and/or magnet  38  replacement. 
         [0031]    In  FIGS. 9-10 , an embodiment of an article of footwear  20  with a pocket  48  mounted magnet  38  is illustrated. In the present embodiment, the magnet  38  is attached to a pocket  48  in the arch segment  30 , and the collection surface  40  extends below the arch ceiling  32 . The collection surface  40  and portions of the periphery surface  42  of the magnet  38  are exposed to the walking surface S. The collection surface  40  is raised above the walking surface S to allow debris D to accumulate on the collection surface  40  without creating a tripping hazard. The collection surface  40  is raised from 0.635 cm to 2.54 cm (0.25 inch and 1.0 inch) above the walking surface S, and preferably is raised 0.635 cm to 1.27 cm (0.25 inch and 0.5 inch) above the walking surface S. The magnet  38  is permanently attached with an adhesive  44  as illustrated in  FIG. 9 , or is removable as illustrated in  FIG. 10 . Removal means  46 , such as tabs, clips or other fasteners, attach the magnet  38  to the pocket  48 , providing for periodic removal. Periodic removal of the magnet  38  allows for cleaning of accumulated debris D and/or magnet  38  replacement. 
         [0032]    In  FIG. 11 , an embodiment of an article of footwear  20  with magnets  38  shaped to fit inside the recesses  39  on the sole  24  is illustrated. The recesses  39  being used with the magnets in this embodiment are created by the tread  37 . The magnets  38  have collection surfaces  40  and are thin enough to be spaced above the walking surface S when they are inserted into the recesses  39 . A preferred type of magnet  38  in this embodiment for insertion into the tread is the type used for refrigerator magnets. The collection surfaces  40  are raised from 0.635 cm to 2.54 cm (0.25 inch and 1.0 inch) above the walking surface S, and preferably are raised 0.635 cm to 1.27 cm (0.25 inch and 0.5 inch) above the walking surface S. The tread  37  is preferably thick enough to create deep recesses  39 . This promotes the spacing of the collections surfaces  40  from the walking surface S. The magnets  38  are permanently or temporarily attached with an adhesive  44 . Periodic removal of the magnets  38  allows for cleaning of accumulated debris D and/or magnet  38  replacement. 
         [0033]    In  FIG. 12 , an embodiment of an article of footwear  20  with a magnet  38  shaped to fit inside the recesses  39  on the sole  24  is illustrated. The recesses  39  being used with the magnets in this embodiment are created by the tread  37 . The tread  37  in this embodiment creates recesses  39  in a continuous pattern such that one magnet  38  can be shaped into one piece for use in the recesses  39 . The absence of an arch section in this embodiment also makes the one piece possible. The magnet  38  has a collection surface  40  and is thin enough to be spaced above the walking surface S when it is inserted into the recesses  39 . A preferred type of magnet  38  in this embodiment for insertion into the tread is the type used for refrigerator magnets. The collection surface  40  is raised from 0.635 cm to 2.54 cm (0.25 inch and 1.0 inch) above the walking surface S, and preferably is raised 0.635 cm to 1.27 cm (0.25 inch and 0.5 inch) above the walking surface S. The tread  37  is preferably thick enough to create deep recesses  39 . This promotes the spacing of the collections surfaces  40  from the walking surface S. The magnet  38  is permanently or temporarily attached with an adhesive  44 . Periodic removal of the magnet  38  allows for cleaning of accumulated debris D and/or magnet  38  replacement. 
         [0034]    In  FIG. 13 , an embodiment of an article of footwear  20  with magnets  38  shaped to fit inside the recesses  39  on the sole  24  is illustrated. The recesses  39  being used with the magnets in this embodiment are created by the tread  37 . The tread  37  in this embodiment creates recesses  39  in a discontinuous pattern such that multiple magnets  38  are shaped for use in the individual recesses  39 . The magnets  38  have collection surfaces  40  and are thin enough to be spaced above the walking surface S when they are inserted into the recesses  39 . A preferred type of magnet  38  in this embodiment for insertion into the tread is the type used for refrigerator magnets. The collection surfaces  40  are raised from 0.635 cm to 2.54 cm (0.25 inch and 1.0 inch) above the walking surface S, and preferably are raised 0.635 cm to 1.27 cm (0.25 inch and 0.5 inch) above the walking surface S. The tread  37  is preferably thick enough to create deep recesses  39 . This promotes the spacing of the collections surfaces  40  from the walking surface S. The magnets  38  are permanently or temporarily attached with an adhesive  44 . Periodic removal of the magnets  38  allows for cleaning of accumulated debris D and/or magnet  38  replacement. 
         [0035]    Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.