Abstract:
A support surface is disclosed for transferring heat from a source to food articles placed adjacent said surface and having a plurality of heat conductive support elements each with at least one passageway therethrough, tubular means in each passageway and having a portion thereof extending beyond the ends of said passageways, and header or tubular means for interconnecting adjacent extending portions of said tubular means for transferring therebetween heated fluid from said source. The method of making the support surface is also disclosed.

Description:
This application is a Division of Ser. No. 08/911,026, filed Aug. 14, 1997 U.S. Pat. No. 5,960,869. 
    
    
     BACKGROUND OF THE INVENTION 
     This invention relates to a support surface for transferring heat from a source to food articles placed adjacent the surface and, more particularly, to a support surface comprising a plurality of side-by-side extruded support elements having fluid passageways therethrough and a novel means of interconnecting the passageways of adjacent support elements. 
     The support surface is generally of the type adapted for use in a cooking and cooling apparatus, as set forth in our U.S. Pat. No. 5,086,693, as well as other methods of cooking such as grilling. 
     Briefly, the support surface is formed by taking a plurality of individual support elements having a substantially flat upper surface and one or more longitudinally extending passageways through it for heated fluid such as water or steam. Tubular means is provided for insertion into the passageways and having a portion thereof extending beyond the ends of the passageways. A header system or additional tubular means can be attached to these end portions for transferring the heated fluid from the passageway of one support element to the passageway of an adjacent support element. The tubular means can comprise a single tubular element which is inserted into and through the entire length of the passageway and expanded into engagement with the side wall of the passageway by compressed air or other pressurized fluid such as oil or water to thereby greatly improve the heat transfer characteristics between the tubular element and the support element. The tube could also be expanded by a mandrel drawn therethrough or the tube could be reduced in diameter or shrunk by subjecting it to low temperature prior to insertion into the passageways. The ends of the single tubular element can be interconnected by flexible base sections clamped thereto or pipe fittings soldered or sweated therebetween. The tubular means can also comprise a plurality of tubular nipple-like elements, one positioned in each end of the passageway and having a portion thereof extending beyond the ends of the passageway. If the passageways are to be connected to a header system having apertures in alignment with the ends of the passageway, the tubular elements can have O-ring seals adjacent the ends thereof for sealing engagement with the walls of the passageways and apertures. The tubular elements and passageways could be in threaded engagement on one end and have O-rings on the other end or be plain on the other end for receiving a flexible hose, pipe fitting or the like. In addition, the apertures in the header could be sized to form an orifice to balance flow through all adjacent parallel tubular element passageways or the tubular elements connecting the apertures to the passageways could themselves be sized to balance flow therethrough. 
     It is therefore the primary object of the present invention to provide a superior support surface for heating food articles. 
     It is another object of the present invention to provide a novel means of interconnecting the fluid passageways of adjacent support surfaces. 
     It is yet another object of the present invention to provide a novel method of making the subject support surface. 
    
    
     Other objects and advantages of the present invention will become apparent and obvious from a study of the following description and accompanying drawings, which are merely illustrative of the present invention. 
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a plurality of support elements of the present invention in side-by-side relationship; 
     FIG. 2 is a side elevational view of the support elements of FIG. 1 taken along the lines  2 — 2  of FIG. 1; 
     FIG. 3 is a cross-sectional view taken along the lines  3 — 3  of FIG. 2; 
     FIG. 4 is a perspective view with a partial breakaway of an assembled support surface of one embodiment of the present invention; 
     FIG. 5 is a plan view of the support surface of FIG. 4 in schematic form; 
     FIG. 6 is an enlarged view of the circled portion in FIG. 5 using one embodiment of the tubular element of the present invention; 
     FIG. 7 is a perspective view of the tubular element shown in FIG. 5; 
     FIG. 8 is a cross-sectional view of the tubular element taken along lines  8 — 8  of FIG. 7; 
     FIG. 9 is an enlarged view of the circled portion in FIG. 5 using another embodiment of the tubular element of the present invention; 
     FIG. 10 is a perspective view of the tubular element of FIG. 9; 
     FIG. 11 is a cross-sectional view taken along lines  11 — 11  of FIG. 10; 
     FIG. 12 is a plan view of the use of another embodiment of a tubular element in support elements of the present invention; 
     FIG. 13 is a perspective view of the tubular element of FIG. 12; 
     FIG. 14 is a cross-sectional view taken along lines  14 — 14  of FIG. 13; 
     FIG. 15 is a plan view of the use of another embodiment of a tubular element in support elements of the present invention using one means of interconnecting the tubular elements; 
     FIG. 16 is a cross-sectional view taken along the lines  16 — 16  of FIG. 15; and 
     FIG. 17 is a plan view of the use of another means of interconnecting the tubular elements. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to the drawings where like characters of reference indicate like elements in each of the several views, numeral  10  in FIG. 1 refers generally to a plurality of support elements  12  of the present invention arranged in side-by-side relationship. The support elements  12  are typically made by extruding a metal such as aluminum into a shape having a flat upper surface  14  and one or more longitudinally extending passageways  16 . For purposes of illustration, a support element  12  having two passageways  16  per element as shown in FIGS. 2 and 3. The upper surface  14  can be TEFLON coated if desired. 
     When the support elements  12  are arranged in side-by-side relationship as shown in FIG.  4  and connected to headers  18 ,  20 , they provide a planar support surface on which food articles such as beef, chicken, etc. can be placed usually in a pan or tray (not shown) placed adjacent the planar surface. If a heated or cooled fluid such as water is then passed through the passageways  16  of the support elements  12  (see arrows) as disclosed in our above referred to U.S. Pat. No. 5,086,693, the food articles on the aforementioned tray can be heated or cooled depending on the temperature of the fluid. 
     The manner of the fluid interconnection of the fluid passageways  16  of each support element  12  with the headers  18 ,  20  or each other to form a continuous fluid circuit from a source of heated or cooled fluid through the entire support surface and back to the source is the primary subject of the present invention. 
     The headers  18 ,  20 , as will be seen in FIG. 5, each have a longitudinally extending through bore  22  and a plurality of spaced-apart transverse bores  24  in communication with the bore  22 . When the support elements  12  are arranged in side-by-side relationship, as shown in FIGS. 4 and 5, the end of the passageways  16  are in alignment with the transverse bores  24  of the headers  18 ,  20 . In order to provide a fluid tight means for the passage of the aforementioned heat transfer fluid, a connector in the form of a tubular element  26  is shown extending a distance into and between each of the transverse bores  24  and passageways  16  of the headers  18 ,  20  and support elements  12 , respectively. 
     In one embodiment, the tubular element  26  is shown and referred to in FIGS. 6-8 by numeral  26 ( a ) and having a through bore  28  and one or more spaced-apart circumferential grooves  30  adjacent each end thereof. An O-ring seal  32  of elastomeric material resides in each of the grooves  30 . As the tubular elements  26 ( a ) are inserted into the respective aligned passageways  16  and bores  28 , the O-ring seals  32  engage the walls thereof to provide a fluid tight seal in a well known manner. 
     In a second embodiment, the tubular element  26  is shown and referred to in FIGS. 9-11 by numeral  26 ( b ) and having a through bore  34  and one or more spaced-apart circumferential grooves  36  adjacent one end only. The other end of element  26 ( b ) has a plurality of threads  38  which mate with corresponding threads  40  in transverse bores  24  in headers  18 ,  20 . The tubular elements  24   b  are first screwed into the threaded bores  40  and then are inserted into passageways  16  of the headers  18 ,  20  and support elements  12 , respectively, to again form a fluid tight seal. It being understood, of course, that conversely the passageways  16  could be threaded to receive the threaded end  38  and the transverse bores  24  be smooth to accommodate the O-ring seals  32 . 
     In a third embodiment, the tubular element  26  is shown and referred to in FIGS. 12-14 by numeral  26 ( c ) and having a through bore  42  and threads  44  on one end thereof. The other end  46  of element  26 ( c ) is cylindrical. As can be seen specifically in FIG. 12, the tubular elements  26 ( c ) are screwed into threaded cores  48  of the support elements  12 . A flexible tubular hose  50  is then positioned over the cylindrical ends  46  of adjacent elements  26 ( c ) and maintained in fluid tight relationship therewith by clamps  52  in a well known manner. As can be seen by referring to FIG. 5, if the through bores  22  in the headers  18 ,  20  are unobstructed, the flow of fluid in passageways  16  is parallel through the plates  12  from header  18  to header  20 . However, by the strategic insertion of plugs  66  (shown in phantom), made of flexible material such as rubber, in the through bores  22 , the flow through the passageways  16  of plates  12  and headers  18 ,  20  can be made serpentine rather than parallel. If it is desired to balance or equilibrate the flow through bores  24  and passageways  16  of adjacent support elements  12  when arranged for parallel flow (no plugs  66 ), orifices  68   a  as shown in phantom in FIGS. 5 and 6 can be formed in transverse bores  24  or the orifice  68   b  can be formed in the tubular elements  26   a - 26   c  as shown, for example, in FIG. 8 
     In a fourth embodiment, the tubular element is a continuous length of tubing  54  such as copper which is longer than the length of passageways  16 . The tubing  54  is inserted into the passageway  16  of each support element  12  leaving a short portion  56  extending beyond the ends of the passageways  16 . After insertion of the tube  54  in a passageway  16 , a fluid (not shown) such as air, water, oil or the like is passed through the tube  54  under pressure sufficient to expand the tube  54  into better heat conductive relationship with the wall constituting the passageway  16 . A mandrel (not shown) can also be drawn through the tube  54  thus expanding it into engagement with passageway  16  or the tube  54  could be super cooled to thus decrease its diameter to permit insertion into passageway  16  whereupon cooling the tube  54  would expand to effect a tight fit with passageway  16 . Alternatively, the support element  12  itself can be brought under pressure to force the passageway  16  into heat conductive engagement with the tube  54 . The short end portions  56  of each of the tubes  54  are connected to end portions  56  of adjacent tubes  54  by means of hose  50  and clamps  52  as shown and described with regard to embodiment three to thereby form a serpentine channel for the transfer fluid to pass between support elements  12  as shown in FIGS. 15 and 16. 
     Referring to FIG. 17, if the transfer fluid is of a very high temperature and/or pressure, the hose  50  and clamp  52  arrangement can be eliminated and metal L-shaped, pipe-type fittings  58  and nipples  60  can be used. These fittings  58 ,  60  would be connected to each other and the end portions  56  by solder  62  in a well known manner. Further, the same pipe-type fittings  58 ,  60  could be used to connect cylindrical-shaped ends  46  of embodiment three by soldering or welding  62  instead of using hose  50  and clamps  52  as shown in FIG.  12 . 
     Applicants have thus described in detail their novel support surface comprising a plurality of support elements and the various methods of interconnecting the passageways through each support element to form a fluid tight circuit in serpentine-form for the passage of a heated or cooled transfer fluid. Such a support surface can be adapted for use in an oven described in aforementioned U.S. Pat. No. 5,086,693 as well as many other similar uses. 
     It is apparent that many modifications and variations of this invention as hereinbefore set forth may be made without departing from the spirit and scope thereof. The specific embodiments described are given by way of example only, and the invention is limited only by the terms of the appended claims.