Patent Publication Number: US-2005139739-A1

Title: Magnetic-adhesive mounting device

Description:
FIELD OF THE INVENTION  
      The present invention relates to first structures each comprising a permanent magnets a magnet surface adapted to be positioned along a surface of a second structure comprising a layers of ferrous or ferromagnetic material so that one structures can be supported on the other structure by magnetic attraction, which first structure includes a layer of material that restricts relative movement between the first and second structures in the plane of their adjacent surfaces.  
     BACKGROUND OF THE INVENTION  
      Many structures are known that each comprise at least one permanent magnet having a magnet surface adapted to be positioned along surfaces of structures comprising layers of ferrous or ferromagnetic material so that one of the structures can be supported on the other structure by magnetic attraction. Examples of such structures including a permanent magnet that has a planar surface intended to be supported by a planar surface of a structure including a layer of ferrous or ferromagnetic material are signs (which may bear pictures, sayings, memorabilia, advertising, etc.), hooks, spring clips, containers, or organizers which may be supported along refrigerators, metal furniture or cabinets, metal encased instruments, or the like. One example of such a structure including the permanent magnet which is intended to support the structure including the layer of ferrous or ferromagnetic material is described in U.S. Pat. No. 5,992,807 (Tarulli). In that structure a magnet permanently secured to the dashboard of a vehicle is adapted to removably retain a cell phone along a vertical surface of the magnet due to the magnetic attraction between the magnet and metal parts of the cell phone. Magnetic attraction between such structures provides instant attachment of the structures and good resistance to separation of the structures by pulling one from the other in a direction normal to their planar surfaces, however, it has limited ability to restrict slippage of the planar surfaces of the structures relative to each other. Thus when the planar surfaces of the structures are generally vertical the weight of the supported structure will often cause it to slide along the planar surface of the supporting structure, particularly when the structures are exposed to vibration, shock, or centrifugal forces. U.S. Pat. No. 5,992,807 describes providing “a thin layer of rubber or other suitable material” over the surface of the magnet that “provides a frictional resistance which is supplementary to the magnetic and prevents the cell phone from slipping down”, but provides no specifics concerning the type of rubber or other material to be used, or their effectiveness in preventing such slipping down.  
     DISCLOSURE OF THE INVENTION  
      Like the prior art described above, the present invention provides a first structure comprising a permanent magnet having a magnet surface adapted to be positioned along a surface of a second structure comprising a layer of ferrous or ferromagnetic material so that one of the structures can be supported on the other structure by magnetic attraction. The present invention is significantly improved from those prior art structures, however, in that the first structure further comprises a layer of removable pressure sensitive adhesive having a surface parallel with the magnet surface that is positioned to releasably adhere to the surface of the second structure and thereby significantly restrict slipping of the surfaces of the first and second structures relative to each other. While the adhesion of the layer of removable pressure sensitive adhesive to the planar surface will provide a high force in shear to restrict such slipping, it does not significantly increase the force required to separate the structure from the second structure, which separation is typically caused by manually pulling and/or pealing the supported structure away. This combination of magnetic attraction provided by the magnet to retain engagement of the structures against pulling and/or pealing forces and adhesion of the layer of removable adhesive that retains the relative positions of the structures against shear forces acting in the plane of the engaged surfaces allows the supporting structure to support a supported structure of significantly greater weight in a fixed position than could be supported if the layer of removable adhesive were not present, or if that layer or removable adhesive were replaced by a layer of non-adhesive material such as a layer of “rubber or similar material” as is described in U.S. Pat. No. 5,992,807.  
      The layer of removable pressure sensitive adhesive can extend over the planer magnet surface, or can be in a layer having a surface coplanar with the planer magnet surface which, for example, could extend around that magnet surface or be positioned on a side of that planer magnet surface where it will be biased into engagement with the planar surface of the second structure by torsional forces caused in the first structure resulting from the weight of the supported structure.  
      By removable pressure sensitive adhesive we mean to include the micro-structured relatively low tack and low adhesion type of removable and repositionable pressure sensitive adhesive available from 3M company, St. Paul, Minn. under the trademark “Post-it” (e.g., the removable and repositionable adhesive layer on No. 9416 “Post-it” 0  brand transfer tape commercially available from 3M Company, St. Paul, Minn.), and any other relatively low tack and low adhesion removable and repositionable pressure sensitive adhesive that will adhere to most surfaces, but can be pealed away without leaving a residue and can then again be adhered to a surface, particularly including such adhesives which are micro-structured.  
      By perminant magnet we mean to include the type of flexible or molded permanent magnets sold under the trademark “PLASTIFORM” by the Plastiform division of Arnold Magnetics, Norfolk, Nebr.), and other perminant magnets that may have other structures such as all metal structures. 
    
    
     DESCRIPTION OF DRAWING  
      The present invention will be further described with reference to the accompanying drawing wherein like reference numerals refer to like parts in the several views, and wherein:  
       FIG. 1  is a perspective view of a first embodiment of a device according to the present invention shown attached to a vertical surface;  
       FIG. 2  is a side view of the device of  FIG. 1 ;  
       FIG. 3  is a perspective view of a second embodiment of a device according to the present invention;  
       FIG. 4  is an enlarged sectional view taken approximately along line  4 - 4  of  FIG. 3 ;  
       FIG. 5  is a side view of a third embodiment of a device according to the present invention;  
       FIG. 6  is a rear view of the device of  FIG. 5 ;  
       FIG. 7  is a perspective view of a fourth embodiment of a device according to the present invention; and  
       FIG. 8  is a perspective view of a fifth embodiment of a device according to the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
      Referring now to  FIGS. 1 and 2  of the drawing there is illustrated a first embodiment of a first structure or hook assembly according to the present invention generally designated by the reference numeral  10 . The hook assembly  10  comprises a polymeric support member  12  having a rectangular planer rear surface  13  on which is adhered a rectangular permanent magnet  14  (e.g., a flexible or molded permanent magnet of the type sold under the trademark “PLASTIFORM” by the Plastiform division of Arnold Magnetics, Norfolk, Nebr.). The magnet  14  has a planar magnet surface  16  on its side opposite the support member  12  that is adapted to be positioned along a planar vertically disposed surface  18  of a second structure comprising a layer of ferrous or ferromagnetic material (e.g., a thin steel outer layer of a refrigerator wall or a steel cabinet wall that can have a painted outer surface) so that the hook assembly  10  will be supported along the surface  18  of the second structure by magnetic attraction. The first structure or hook assembly  10  further comprises a layer  20  of removable pressure sensitive adhesive (e.g., that layer  20  being provided by No. 9416 “Post-it” brand transfer tape commercially available from 3M Company, St. Paul, Minn., which comprises a support layer between a layer of strong or permanent pressure sensitive adhesive adhered to the surface  16  and a layer of removable pressure sensitive adhesive that provides the layer  20 ) overlaying the planar magnet surface  16 , which layer  20  of removable pressure sensitive adhesive has an exposed planar surface  21  parallel with that planar magnet surface  13  adapted to releasably adhere to the planar surface  18  of the second structure and thereby restrict slipping of the surface  21  of the hook assembly  10  and the surface  18  of the second structure relative to each other in a direction parallel to those surfaces  21  and  18 . The support member  12  includes a hook-like structure  22  projecting along its side opposite the magnet  14  from which objects may be suspended, as by a cord received in a channel  24  defined by the hook-like structure  22 .  
      A test was performed to determine the ability of a first structure or hook assembly  10  of the type described above to support weight along a vertically disposed surface of a second structure, compared to a similar hook assembly supported on that same vertically disposed surface only by a magnet (called a “magnet only” hook assembly herein), or only by a layer of removable pressure sensitive adhesive (called an “adhesive only” hook assembly herein). Three identical support members  12  of the type described above were used, each having a rectangular planer surface  13  that was 0.63 inch or 1.6 cm wide and 2 inches or 5.08 cm high. A flexible permanent magnet  14  of the type sold under the trademark “PLASTIFORM” by the Plastiform division of Arnold Magnetics, Norfolk, Nebr., about 0.06 inch or 0.15 cm thick and having the same peripheral dimensions as the surface  13  was adhered on the surface  13  of a first one of the support members  12 . Over the surface of that magnet opposite the surface  13  was adhered a layer  20  of removable pressure sensitive adhesive (i.e., that layer  20  being provided by No. 9416 “Post-it” brand transfer tape commercially available from 3M Company, St. Paul, Minn., which included a support layer between a layer of strong or permanent pressure sensitive adhesive that was adhered to the magnet and the layer  20  of removable pressure sensitive adhesive), thereby forming a test hook assembly  10  having the structure described above. A magnet identical to the magnet  14  used in the test hook assembly  10  was adhered on the surface  13  of a second one of the support members  12  to form the “magnet only” hook assembly. A layer  20  of removable pressure sensitive adhesive formed of No. 9416 “Post-it” brand transfer tape and having the same peripheral dimensions as the surface  13  was adhered on the surface  13  of a third one of the support members  12  to form the “adhesive only” hook assembly. The three test hook assemblies were attached to the vertically disposed surface of a painted steel cabinet and increasing numbers of ½ pound weights were hung on the test hook assemblies until they began to slide down or separated from the vertically disposed surface. The “magnet only” hook assembly could only support one ½ pound weight and slid down the vertical surface when the second ½ pound weight was added. The “adhesive only” hook assembly could only support one ½ pound weight and separated from the vertical surface when the second ½ pound weight was added. The test hook assembly  10  having the structure described above supported four ½ pound weights or 2 pound before sliding, which was significantly more than the total amount of weight supported by the other two test hook assemblies. The test hook assembly  10  was found to be easily manually removed from and repositioned on the vertically disposed surface.  
      Another test was done with a product called a “Nifty Products Magnetic Locker Box” which is commercially available from Carolina Pad Company, Charlotte, N.C., and is a plastic rectangular container adapted to hold items that has a permanent magnet with a planar surface along a rear wall of the container by which the container can be magnetically attached to a vertical metal wall, such as the metal wall of a refrigerator, school locker, or office cabinet. The “Locker Box” was magnetically attached to the vertical painted metal wall of an office cabinet. A first ½ pound weight placed in the “Locker Box” did not cause it to move; however, when a second ½ pound weight was placed in the “Locker Box” it would slip along the wall and sometimes drop away from the wall. A strip of ¾ inch wide No. 9416 “Post-it” brand transfer tape commercially available from 3M Company, St. Paul, Minn., was then adhered across the bottom portion of the planer surface of the magnet, and the “Locker Box” was magnetically and adhesively attached to the same vertical metal wall. The “locker Box” could then support eight ½ pound weights (i.e., a total of 4 pounds), and could still be easily manually removed from and repositioned along the vertical wall.  
      Both tests described above were preformed during the first adhesion of the layers of repositionable adhesive to the vertical wall or surface. It was found that each removal and repositioning of those layers of repositionable adhesive along vertical surfaces decreased their effectiveness to help slipping of the perminant magnets along those surfaces, presumably because of increased surface contamination of the layers of repositionable adhesive.  
      Referring now to  FIGS. 3 and 4  of the drawing there is illustrated a second embodiment of a structure or hook assembly according to the present invention generally designated by the reference numeral  30 . The hook assembly  30  comprises a polymeric support member  32  having essentially the same structure as the support member  12  described above, including a planer rectangular rear surface  33  on which is centrally adhered a rectangular permanent magnet  34  (e.g., a flexible or molded permanent magnet of the type sold under the trademark “PLASTIFORM” by the Plastiform division of Arnold Magnetics, Norfolk, Nebr.). The magnet  34  has a periphery spaced from the periphery of the rear surface  33  and has a planar magnet surface  36  on its side opposite the support member  32  that is adapted to be positioned along a planar vertically disposed surface of a second structure comprising a layer of ferrous or ferromagnetic material (e.g., a thin steel outer layer of a refrigerator wall or a steel cabinet wall that can have a painted outer surface) so that the hook assembly  30  will be supported along the surface of the second structure by magnetic attraction. The first structure or hook assembly  30  further comprises a layer  40  of removable pressure sensitive adhesive (e.g., that layer  40  being provided by No. 9416 “Post-it” brand transfer tape commercially available from 3M Company, St. Paul, Minn.) on the rear surface  33  around the periphery of the magnet  34 , which layer  40  of adhesive has a planar surface  41  parallel to and generally coplanar with the planar magnet surface  33 . The planar surface  41  of the layer  40  of removable pressure sensitive adhesive is adapted to releasably adhere to the planar surface of the second structure and thereby restrict slipping of the surfaces  36  and  41  and the hook assembly  30  along the surface of the second structure. The support member  32  includes a hook-like structure  42  projecting along its side opposite the magnet  34  from which objects may be suspended, as by a cord received in a channel  44  defined by the structure  42 .  
      Referring now to  FIGS. 5 and 6  of the drawing there is illustrated a third embodiment of a structure or hook assembly according to the present invention generally designated by the reference numeral  50 . The hook assembly  50  comprises a polymeric support member  52  having a planer rectangular rear surface  53 . Over an upper portion of that rear surface  53  is adhered a rectangular permanent magnet  54  (e.g., a flexible or molded permanent magnet of the type sold under the trademark “PLASTIFORM” by the Plastiform division of Arnold Magnetics, Norfolk, Nebr.) having a planar magnet surface  56  on its side opposite the support member  52  that is adapted to be positioned along a planar vertically disposed surface of a second structure comprising a layer of ferrous or ferromagnetic material (e.g., a thin steel refrigerator or cabinet wall that can have a painted outer surface) so that the hook assembly  50  will be supported along the surface of the second structure by magnetic attraction. The bottom peripheral edge of the magnet  54  is spaced from the bottom edge of the rear surface  53  and the first structure or hook assembly  50  further comprises a layer  60  of removable pressure sensitive adhesive (e.g., that layer  20  being provided by No. 9416 “Post-it” brand transfer tape commercially available from 3M Company, St. Paul, Minn.) on the rear surface  53  between the adjacent bottom peripheral edges of the rear surface  53  and of the magnet  54 . That layer  60  of removable pressure sensitive adhesive has a planar surface  61  parallel and coplanar with that planar magnet surface  53  that is adapted to releasably adhere to the planar surface of the second structure and thereby restrict slipping of the surfaces  56  and  61  and the hook assembly  50  along the surface of the second structure. The support member  52  includes a hook-like structure  62  projecting along its side opposite the magnet  54  from which objects may be suspended, as by a cord received in a channel  64  defined by the structure  62 . The weight of objects supported by the hook-like structure  62  will cause a torsional force in the support member  52  that will press the layer  60  of removable pressure sensitive adhesive into firm engagement the second structure on which it is attached.  
      Referring now to  FIG. 7  of the drawing there is illustrated a fourth embodiment of a structure according to the present invention generally designated by the reference numeral  70 . The structure  70  comprises a rectangular permanent magnet  72  (e.g., a flexible or molded permanent magnet of the type sold under the trademark “PLASTIFORM” by the Plastiform division of Arnold Magnetics, Norfolk, Nebr.) having front and rear planar magnet surfaces  73  and  74 , and a layer  75  of removable pressure sensitive adhesive over the rear magnet surface  74  (e.g., that layer  75  being provided by No. 9416 “Post-it” brand transfer tape commercially available from 3M Company, St. Paul, Minn.). A display object provided by a layer  76  of material (e.g., paper, polymeric sheet material, or paint) having graphics  77  along its outer surface opposite the magnet  72  is attached or adhered over the front magnet surface  73 . A surface  78  of the layer  75  of removable pressure sensitive adhesive opposite the magnet  72  is adapted to be releasably adhered to and to be magnetically attached along a vertically disposed surface  79  of a second structure that comprises ferrous or ferromagnetic material. The structure  70  could, for example, be the size of a conventional refrigerator magnet, or could be very much larger and used to cover a metal substrate with graphics  77  that are decorative and/or provide political or advertising information. Instead of being the layer  76  of material having graphics  77  along its outer surface, the display object could, for example, be a light fixture, such as a temporary emergency light of the type sometimes used on police vehicles, or could be an instrument such as a thermometer, barometer, or the like, or could be any other object that a person wishes to display along a surface  79  of a second structure that comprises ferrous or ferromagnetic material.  
      Referring now to  FIG. 8  of the drawing there is illustrated a fifth embodiment of a structure according to the present invention generally designated by the reference numeral  90 . The structure  90  comprises a rectangular permanent magnet  92  (e.g., a flexible or molded permanent magnet of the type sold under the trademark “PLASTIFORM” by the Plastiform division of Arnold Magnetics, Norfolk, Nebr.) having front and rear planar magnet surfaces  93  and  94 , a layer  95  of removable pressure sensitive adhesive over the rear magnet surface  94 , and a layer  96  of removable pressure sensitive adhesive over the front magnet surface  93  (e.g., those layers  95  and  96  being provided by No. 9416 “Post-it” brand transfer tape commercially available from 3M Company, St. Paul, Minn.) so that the layers  96  and  97  of removable pressure sensitive adhesive have planar surfaces  100  and  101  respectively which are parallel and coplanar with the planar magnet surfaces  94  and  93 . The surface  100  is adapted to releasably adhere to and be magnetically attached along a vertically disposed surface  103  of a second structure that comprises ferrous or ferromagnetic material, whereas the surface  101  is adapted to releasably adhere to the surfaces of ferrous or ferromagnetic objects positioned along the surface  101  to thereby restrict slipping of those objects in the plane of the surface  101 . Examples of such objects could include knives, scissors, wrenches, dental tools, sockets, etc., and instead of being planar, the surface  101  could be shaped to make more intimate contact with non planar objects, such as by having transverse semi-cylindrical and/or V-shaped grooves adapted to receive portions of cylindrical or rectangular objects.  
      The present invention has now been described with reference to several embodiments and modifications thereof. It will be apparent to those skilled in the art that many changes can be made in the embodiments described above without departing from the scope of the present invention. For example, the hook-like structure  22 ,  42 , or  62  on the support member  12 ,  32 , or  52  of the first structure  10 ,  30 , or  50  described above could be replaced by other means for engaging a third structure or object such as a spring clip or clamp, a pin, a cup-like structure or container, or an organizer; and/or the support members  12 ,  32 , or  52  could have graphics (i.e., pictures, sayings, memorabilia, advertising, etc.) on their surfaces opposite the magnet  14 ,  34 , or  54 . The hook-like structure  22 ,  42 , or  62  on the support member  12 ,  32 , or  52  of the first structure  10 ,  30 , or  50  described above could be replaced by other objects that need support such as sensors for instruments, novelty gadgets, shelves, electrical termination boxes, light fixtures, and radio antennas and other temporary articles mounted on automobiles, trucks and railroad cars. Release liners could be provided over the exposed surfaces of the layers of removable pressure sensitive adhesive on the structures described above to restrict contamination of those adhesive surfaces prior to use. Thus, the scope of the present invention should not be limited to the structures described in this application, but only by the structures described by the language of the claims and the equivalents thereof.