Abstract:
A magnetic heat sink device and a heat removal method employs a heat sink device comprising a base assembly and a handle which extends in upright fashion from the base assembly. The base assembly has an array of fins. Magnets are received in holders of the base assembly and are magnetically bondable to an underlying metal attachment member so that the array of fins is in thermal communication with the member. Heat in the vicinity of the member is conducted to the fins and dissipated from the fins into the ambient environment.

Description:
BACKGROUND 
       [0001]    The present disclosure relates generally to methods and devices for attaching material to roofs. More particularly, the present disclosure relates to methods and devices for the securement of a membrane which overlies sheets of thermal insulation secured to a roof substrate by use of attachment discs. 
         [0002]    In roof construction technology for which the present disclosure has specific application, sheets of thermal insulation are secured to the top of a roof structure by metallic attachment or compression discs. The members are placed on the top of the insulation and typically secured via a fastener to the substrate portion of the roof in a grid-like array. Stand-up installation tools which automatically feed plates and drive fasteners may also be used. The upper surfaces of the metallic members are affixed with a heat activated adhesive that becomes active by heating the discs. A water impervious membrane is laid over the insulation and the discs. The bottom surface of the membrane is bonded to the members by the adhesive. 
         [0003]    There are several types of induction heating devices which are conventionally employed to heat the member and activate the adhesive. Such devices are moved across the membrane and positioned over the underlying disc. An induction heating coil interacts with the metallic member to set up a magnetic field with the member and to ultimately heat the attachment member and thereby activate the adhesive. 
         [0004]    U.S. Pat. No. 7,399,949 discloses a heating apparatus employed for attaching membrane material to attachment members that hold sheets of thermal insulation at the top of a roof substrate. The heating apparatus emits a magnetic field that raises the temperature of the member and activates the heat activated adhesive disposed on the top of the disc. The heating apparatus includes a set of bottom guides to allow a user to find the attachment members mechanically without actually seeing the member beneath the top membrane layer. A fine locator circuit employs a magnetic field to locate the disc. The apparatus allows a user to stand upright on the membrane while operating the apparatus. Upon cooling, the adhesive becomes adhered to the bottom surface of the top membrane layer. 
       SUMMARY 
       [0005]    Briefly stated a magnetic heat sink device for removing heat from a metallic heated attachment member affixed with heat activated adhesive generally comprises a base assembly and a handle extending in upright fashion from the base assembly. The base assembly has a base which has a periphery disposed radially outwardly from a longitudinal axis. Holders in the form of sockets are defined adjacent the periphery of the base, and magnets are received in the sockets such that the magnets are positioned adjacent a baseplate having a bottom surface. An array of fins in thermal communication with the base forms a heat path so that heat is dissipated from the fins into the ambient environment. 
         [0006]    In one preferred embodiment, the base assembly is generally symmetric about the longitudinal axis, and the handle extends from the base assembly in a direction generally parallel with the longitudinal axis. The array of fins is generally symmetric about the longitudinal axis. The handle is preferably coaxial with the longitudinal axis. 
         [0007]    The array of fins preferably comprises a first set of fins and an alternating second set of fins. The first set of fins comprises equiangularly spaced fins that taper from a lower portion to an upper portion generally convergent toward the handle. The second set of fins comprises equiangularly spaced fins having a smaller surface area in comparison with the first set of fins. The array of fins in one embodiment is composed of heat conductive plastic material. 
         [0008]    The magnetic heat sink device employs the magnets to magnetically bond with the metal member or attachment member. The base assembly is located in close proximity to the attachment member. An array of fins is in thermal communication with the base assembly so that heat in the vicinity of the attachment member is conducted to the fins and dissipated therefrom into the ambient environment. 
         [0009]    A method of attaching a membrane to an underlying upper surface of a metallic attachment member having a heat activated adhesive comprises heating the member via an induction tool positioned above the membrane and member. The attachment member is heated by the inductive tool to activate the adhesive. The inductive tool is removed from the vicinity of the attachment member. A heat sink device is positioned over the attachment member. The heat sink device is magnetically bonded to the attachment member and heat is removed from the member through the device into the ambient environment. 
         [0010]    A thermal path is established between the attachment member and an array of fins on the heat sink device. In a preferred method, magnetic bonds are established between the heat sink device and the attachment member. The step of positioning the heat sink device further comprises using a handle to magnetically position the heat sink device. The heat sink device is preferably substantially centered relative to the member. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]      FIG. 1  is a perspective view of one embodiment of a magnetic heat sink device; 
           [0012]      FIG. 2  is a cross-sectional view of the base assembly of the embodiment of the heat sink device of  FIG. 1 , a segment of a roof, insulation, a metallic attachment member, threaded fastener, and water impervious membrane also being depicted in cross-section; 
           [0013]      FIG. 3  is a partially exploded view of an embodiment of the base and plurality of magnets, the array of fins and the handle being omitted for clarity; 
           [0014]      FIG. 4  is a top plan view of the base of  FIG. 3 ; 
           [0015]      FIG. 5  is a bottom plan view of the base assembly of  FIG. 1 ; 
           [0016]      FIG. 6  is a top plan view of the base assembly of  FIG. 1 , the handle being omitted for clarity; and 
           [0017]      FIG. 7  is an enlarged cross-sectional view of one of the plurality of holders of the base shown in  FIGS. 3 and 4 . 
       
    
    
     DETAILED DESCRIPTION 
       [0018]    With reference to the drawings wherein like numerals represent like parts throughout the several figures, a magnetic heat sink device is generally designated by the numeral  10 . The magnetic heat sink device  10  is a hand held device which is adapted to magnetically bond with an insulation attachment member and to function as a heat sink which pulls heat from the member in a highly efficient manner. The magnetic heat sink  10  is relatively lightweight, allowing a user to easily manipulate and position the magnetic heat sink  10 . In addition to its easily manipulable dimensions, the favorable heat dissipating features of the magnetic heat sink  10  cause the overlying membrane to bond to the member in an accelerated fashion. 
         [0019]    Referring to  FIGS. 1 and 2 , the heat sink device  10  generally comprises a base assembly  11  having a base  12  and an array of fins  14 , and a handle  16 . The heat sink device  10  has a longitudinal axis A-A, as shown in  FIG. 1 . 
         [0020]    As shown in  FIG. 2 , the heat sink device  10  is designed for use with a metallic attachment member  18 , such as a compression disc or plate, employed in roof construction. As will be discussed in greater detail below, after a fastener  22  secures the attachment member  18  to the roof  20 , an induction heating apparatus (not shown) melts an adhesive (not shown) on the surface of the member  18 , and activates the adhesive, thereby bonding with the underside of a water impervious membrane  24 . The heat sink device  10  is then moved to a position over the attachment member  18  so that the base assembly  11  rests on the membrane  24 . 
         [0021]    As seen in  FIGS. 2 ,  3  and  7 , the base  12  carries a plurality of magnets  26 , which form a magnetic bond with the member  18 . The base  12  has a lower baseplate  13 . The base  12  has a periphery  28  which is disposed radially outwardly from the longitudinal axis A-A. A plurality of holders in the form of generally cylindrical sockets  30  which are sized to receive the magnets  26 , are defined adjacent the periphery  28 . As shown in  FIG. 3 , the sockets  30  may be slightly raised from the surface of the base  12 . In the embodiment shown in  FIGS. 3 and 4 , the base  12  has a generally circular periphery, and the sockets  30  are arranged concentrically about the longitudinal axis A-A. 
         [0022]    In one embodiment shown in  FIGS. 3 and 7 , the magnets  26  and the sockets  30  are cylindrical. The sockets  30  have an interior surface  32  having a first portion  31  and a second portion  33 . As best seen in  FIG. 7  the first portion  31  may be castellated. The castellated feature functions to minimize contact between the magnets  26  and the base. A plurality of inserts  34  ( FIG. 3 ) also cooperate with the socket  30  to retain the magnets  26 . The inserts  34  envelop the top and sides of the magnets, and engage the interior second portion  33 , forming a press-fit connection, as shown in  FIGS. 3 and 4 . The inserts  34  tend to thermally isolate the top surfaces of the magnets. Other structures may be employed to thermally isolate the magnets or minimize thermal conduction between the base and the magnets. As shown in  FIGS. 3 and 7 , the sockets  30  may also have a socket wall  37  which projects above an upper surface  39  of the base  12 . 
         [0023]    Referring to  FIGS. 1-4 , the handle  16  extends in an upright fashion from the base assembly  11 . In one embodiment best seen in  FIGS. 3 and 4 , the base  12  may have a plurality of resilient arms  36 . The arms  36  define a handle retention pocket  38  coaxial with the longitudinal axis A-A. The pocket  38  is configured to retain the handle  16  against the base assembly  11 . The sockets  30  are circumferentially spaced adjacent the periphery  28  and concentric with the longitudinal axis A-A. 
         [0024]    Referring to  FIG. 5 , the baseplate  13  also has a bottom surface  35  axially proximate to the magnets  26 . The bottom surface  35  defines a plane which is oriented perpendicular to the longitudinal axis A-A. The baseplate  13  is constructed of a ferromagnetic material, ensuring that the base  12  is centered over the member  18  when the water impervious membrane is laid on top of the member  18 . The ferromagnetic material of the baseplate  13  propagates the magnetic force of the magnets  26 , and magnetically bonds the baseplate  13  to the metallic member  18 . A flat bottom surface  35  ensures that as much surface area of the base  12  makes intimate contact with the member  18  as possible, to efficiently conduct heat away from the member  18  and into the ambient environment. 
         [0025]    In one embodiment shown in  FIG. 5 , the baseplate  13  is a metal annulus. The metal annulus surrounds a central recess  40 . As seen in  FIG. 5 , the central recess  40  is coaxial with the longitudinal axis A-A. The central recess  40  accommodates any protrusion caused by the fastener head and ensures surface-to-surface contact of the baseplate  13  against the membrane  24 . 
         [0026]    As shown in  FIGS. 1 ,  2  and  6 , the array of fins  14  are arranged in thermal communication with the base  12 . Referring specifically to  FIG. 2 , the array of fins  14  are mounted in thermal communication to the base  12 . The array of fins  14  efficiently transfers heat from the base  12  into the ambient environment by presenting a relatively large surface area adjacent the base  12  given the compact dimensions of the base assembly. As seen in  FIG. 6 , the fins  14  are generally symmetric about the longitudinal axis A-A, and may be equiangularly spaced about the longitudinal axis A-A. 
         [0027]    In one embodiment, the fins  14  are composed of a heat conductive plastic material. The fins  14  are integrally molded to the base  12  to ensure that the fins  14  are configured in thermally conductive contact with the base  12 , and in particular the metal baseplate  13 . 
         [0028]    In one embodiment shown in  FIGS. 1 and 6 , the array of fins  14  comprises two sets of fins, a first set of identical fins  42 , and an alternating second set of identical fins  44 . The first set of fins  42  comprises a plurality of equiangularly spaced fins of a generally uniform thickness. As shown in  FIGS. 1 ,  2 ,  5  and  6 , the first set of fins  42  preferably taper from a bottom end portion  46  disposed at a periphery  41  of the baseplate  13  to an upper portion  48 . The upper portion  48  is generally convergent toward the handle  16 . 
         [0029]    In one embodiment shown in  FIGS. 2 and 5 , the array of fins  14  has an interrupted annular portion  50 , which extends radially outwardly from the baseplate periphery  41 , and flares slightly angularly away from the plane defined by the bottom surface  35  of the baseplate  13 . As seen in  FIG. 5 , the bottom end portion  46  of each fin  42  interrupts the annular portion  50  and is radially inwardly contiguous with the baseplate periphery  41 . As seen in  FIGS. 2 ,  5  and  6 , each of the fins of the first set  42  projects radially beyond a periphery  52  of the interrupted annular portion  50 . 
         [0030]    As seen in  FIGS. 1 and 6 , the second set of fins  44  comprises a plurality of identically angularly spaced fins of a generally uniform thickness. The second set of fins  44  does not extend as far radially from the longitudinal axis A-A as the first set of fins  42 , and in one embodiment depicted in  FIG. 6 , the second set of fins  44  extend radially to the periphery  52  of the interrupted annular portion  50 . 
         [0031]    As best seen in  FIGS. 1 ,  2  and  6 , the second set of fins  44  projects axially from the annular portion  50  to an upper shoulder  56  intermediate the annular portion  50  and the upper portion  48  of the first set of fins  42 . In one embodiment best seen in  FIGS. 2 and 6 , the upper shoulder  56  of the second set of fins  44  is contiguous with an annular shoulder  54  which is sized and configured to envelop the circumferentially arranged sockets  30  and magnets  26  of the base  12  ( FIG. 2 ). The second set of fins  44  are sized to have a much smaller surface area than the first set of fins  42 . The dimensions of the first set of fins  42  in comparison with the second set of fins  44  provides an angular array of heat communication channels to the ambient environment for the array of fins  14 , and enhances the rate at which the fins  14  conduct heat away from the attachment plate  18 . 
         [0032]    With reference to  FIG. 2 , a method of attaching a water impervious membrane  24  to an underlying upper surface of a metallic member having a heat activated adhesive (not shown) is also contemplated. The heat sink device  10  effectively sets the adhesive, and reinforces the bonds between the attachment member  18  and the water impervious membrane  24 . 
         [0033]    First, an induction heating tool (not shown) is positioned above the membrane  24  and the attachment member  18 . After the heat induction tool is removed from the attachment member  18 , the heat sink device  10  is positioned over the member  18 . A magnetic force created by the magnets  26  is propagated through the baseplate  13  and the heat sink device  10  forms a magnetic bond with the attachment member  18 . 
         [0034]    The heat sink device  10  is provided with an array of fins  14  configured such that an efficient thermal path is established between the attachment member  18  and the fins  14 . The unique arrangement and structure of the fins  14  provide thermal pathways which rapidly cool the attachment member  18  by presenting a relatively large surface area of the device  10  for exposure to the ambient atmosphere, despite the compact dimensions of the base assembly  11 . The fins  14  play the key role in radially conducting heat away from the attachment member  18 , thereby rapidly curing the adhesive (not shown) and ensuring a strong adhesive bond between the top of the attachment member  18  and the water impervious membrane  24 . Severing the temporary magnetic bond between the device  10  and the member  18  has no effect on the integrity of the adhesive bond. 
         [0035]    The step of positioning the heat sink device may comprise using a handle to magnetically position the heat sink device  10 . For optimal function, the heat sink device  10  is substantially centered relative to the attachment member  18 , e.g., the central axis A-A aligns with the central axis of the fastener  22 . 
         [0036]    While a preferred embodiment has been set forth for purposes of illustration, the foregoing description should not be deemed a limitation of the invention herein. Accordingly, various modifications, adaptations and alternatives may occur to one skilled in the art without departing from the spirit and scope of the invention.