Abstract:
A portlight for a marine vessel including a lens having an outer surface, an inner surface and a first sealing surface disposed at a first angle relative to the outer surface, wherein the first angle is greater than ninety degrees, a portlight frame having a flange, an extension and a second sealing surface disposed at a second angle relative to an outer surface of the flange, wherein the second angle is less ninety degrees and supplementary to the first angle, a sealing gasket disposed between the first and second sealing surfaces, and a hinge rotatably secured to the extension and fixedly secured to the lens, wherein rotation of the hinge to a closed position causes the first sealing surface to compress the sealing gasket against the second sealing surface in the absence of undesirable shearing of the gasket.

Description:
FIELD OF THE INVENTION 
       [0001]    The invention broadly relates to gaskets, more specifically to angled gaskets, and even more particularly to an angled gasket for a portlight. 
       BACKGROUND OF THE INVENTION 
       [0002]    Portlights are constructed from many materials including but not limited to stamped and formed stainless sheet, extruded and cast aluminum and molded plastic. Portlights come in many styles and shapes, having different cross sections and mounting designs based on the needs of the ship or boat manufacturer. U.S. Pat. Nos. 5,758,593 and 5,842,433 provide examples of modern portlight designs, and such patents are incorporated herein by reference. 
         [0003]    It is important to remember that a portlight is an inward opening device, with hydraulic pressure trying to push the lens inward. Traditionally, ports, e.g., port  10 , are mounted from the inside of the vessel, with spigot  12  passing through inner wall  14  and projecting out. In such ports, hinges  16  and the dogs are mounted on surface  18  as shown in  FIGS. 1A and 1B . When port  10  is in a closed position, portlight  20  compresses gasket  22  against surface  24 . The portion of gasket  22  which may be subject to shearing or tearing, as described infra, is shown by broken line portion  26  of gasket  22 . Portlight designers face significant challenges, depending on the sealing pressure to be achieved, to design a hinge and gasket and cross section that allows the lens element to rotate down and compress the gasket without shearing or tearing it on the hinge side of the portlight. 
         [0004]    All gaskets must be compressed to seal. Foam gaskets typically need to be compressed 15-20%. Hard rubber gaskets are compressed less, but can not tolerate any shearing action or the density of the gasket will not allow the portlight lens to close. 
         [0005]    It should be appreciated that the sealing of the rotating lens opposite of the hinge does not present as great of an issue as the portion of the gasket opposite the hinge. Regardless of where the hinge is located, the gasket sealing surfaces opposite the hinge come down with an almost pure vertical line of travel, referencing the horizontal lens element when it is in its final closed position. Unless specifically noted, all further discussions herein are with respect to the hinge side of the portlight. 
         [0006]    One of ordinary skill in the art will appreciate that a portlight hinge is typically positioned at least one-half inch outboard of the gasket. (See  FIGS. 3A and 3B ). The rotational axis of hinge  50 , i.e., pin  52 , is positioned approximately one-half inch from the center of gasket  54 , depicted by the length shown by bi-directional arrow  56 . A one-half inch offset results in some interference with the edge of the gasket and a shearing action on the gasket as it closes. It is known that the higher hinge  50  is positioned above the plane of lens  58 , the worse the situation becomes. Contrarily, if hinge  50  is on the same plane as gasket  54  and only offset a small amount, e.g., one-quarter to one-half inch, the shearing action between gasket  54  and sealing surface is almost eliminated. However, such an arrangement cannot be used in any portlight design that can be readily used on a vessel of normal construction. Conversely, the higher the position of hinge  50  the better, which results in less offset of the position of hinge  50  being required. As shown in  FIGS. 3A and 3B , hinge  50  is positioned having an offset of one-half inch (shown by bi-directional arrow  56 ) and a height of seven-eighths inch above the center of gasket  54  (shown by bi-directional arrow  60 ) substantially removed any detrimental shearing forces between gasket  54  and sealing surface  62 . Portlight  64  is arranged to be installed through vessel wall  66  from the outside of wall  66 , and further includes inner ring  68  which is used to conceal securing hardware on the inner surface of wall  66 . 
         [0007]      FIG. 4  depicts a prior art portlight design disclosed in U.S. Pat. No. 5,758,593. One of ordinary skill in the art will recognize that when lens  70  is moved down to outer surface  72  of gasket  74  and hinge pin  76  is left in the same position, portion  78  of gasket  74  is sheared off, i.e., the portion of gasket  74  contained within the broken line. It is possible to form a portlight as depicted in  FIG. 5 ; however, frame  80  must be made sufficiently wide to accommodate hinge  82 . Such a portlight is difficult to manufacture as well as expensive. Furthermore, the width of frame  80  would be aesthetically offensive and thereby render the portlight not commercially viable. 
         [0008]    As can be derived from the variety of devices and methods directed at forming a portlight with a gasket seal, many means have been contemplated to accomplish the desired end, i.e., long term consistent and repeated sealing of the portlight assembly. Heretofore, tradeoffs between manufacturing cost and complexity and overall performance were required. Thus, there is a long-felt need for a portlight gasket arrangement which minimizes or removes the shearing forces present in gaskets used in known portlight designs. 
       BRIEF SUMMARY OF THE INVENTION 
       [0009]    The present invention is particularly useful for portlights that are installed from the outside of the vessel, and as such the dogging and hinging structures must hang off of a surface that passes though the hole cut in the vessel side. (See  FIG. 7A ). 
         [0010]    The present invention broadly comprises a portlight for a marine vessel including a lens having an outer surface, an inner surface and a first sealing surface disposed at a first angle relative to the outer surface, wherein the first angle is greater than ninety degrees, a portlight frame having a flange, an extension and a second sealing surface disposed at a second angle relative to an outer surface of the flange, wherein the second angle is less ninety degrees and supplementary to the first angle, a sealing gasket disposed between the first and second sealing surfaces, and a hinge rotatably secured to the extension and fixedly secured to the lens, wherein rotation of the hinge to a closed position causes the first sealing surface to compress the sealing gasket against the second sealing surface in the absence of undesirable shearing of the sealing gasket. 
         [0011]    In some embodiments, the first angle ranges from about 120 degrees to about 150 degrees, the second angle ranges from about 30 degrees to about 60 degrees and a sum of the first and second angles is about 180 degrees. In some embodiments, the first angle is about 135 degrees and the second angle is about 45 degrees. In some embodiments, the gasket is fixedly secured to the first or second sealing surface. In some embodiments, the marine vessel includes a vessel wall, the vessel wall includes an outer surface and the portlight frame is disposed within an opening in the vessel wall and the flange is secured against the outer surface of the vessel wall. In some embodiments, the outer surface of the lens is substantially coplanar with the outer surface of vessel wall. 
         [0012]    In some embodiments, the present invention portlight further includes a lens support frame fixedly secured between the hinge and the lens, wherein the hinge is positioned directly above the lens support frame. 
         [0013]    The present invention broadly comprises a portlight for a marine vessel including a lens having an outer surface, an inner surface and a first sealing surface disposed at a first angle relative to the outer surface, wherein the first angle is greater than ninety degrees, a portlight frame having a flange, an extension and a second sealing surface disposed at a second angle relative to an outer surface of the flange, wherein the second angle is less ninety degrees and supplementary to the first angle, a sealing gasket disposed between the first and second sealing surfaces, and a hinge rotatably secured to the extension and fixedly secured to the lens, wherein rotation of the hinge to a closed position causes the first sealing surface or the second sealing surface to approach the sealing gasket substantially perpendicularly, and to compress the sealing gasket between the first sealing surface and the second sealing surface in the absence of undesirable shearing of the sealing gasket. 
         [0014]    In some embodiments, the first angle ranges from about 120 degrees to about 150 degrees, the second angle ranges from about 30 degrees to about 60 degrees and a sum of the first and second angles is about 180 degrees. In some embodiments, the first angle is about 135 degrees and the second angle is about 45 degrees. In some embodiments, the gasket is fixedly secured to the first or second sealing surface. In some embodiments, the marine vessel includes a vessel wall, the vessel wall includes an outer surface and the portlight frame is disposed within an opening in the vessel wall and the flange is secured against the outer surface of the vessel wall. In some embodiments, the outer surface of the lens is substantially coplanar with the outer surface of vessel wall. 
         [0015]    In some embodiments, the present invention portlight further includes a lens support frame fixedly secured between the hinge and the lens, wherein the hinge is positioned directly above the lens support frame. 
         [0016]    It is a general object of the present invention to provide a portlight having an angled gasket and sealing surfaces arranged to minimize and nearly eliminate shearing forces affecting the gasket. 
         [0017]    It is another general object of the present invention to permit the placement of a hinge directly above a lens support frame without obscuring view through the portlight lens. 
         [0018]    These and other objects and advantages of the present invention will be readily appreciable from the following description of preferred embodiments of the invention and from the accompanying drawings and claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0019]    The nature and mode of operation of the present invention will now be more fully described in the following detailed description of the invention taken with the accompanying drawing figures, in which: 
           [0020]      FIG. 1A  is a partial cross sectional view of a prior art portlight assembly in a closed position; 
           [0021]      FIG. 1B  is a partial cross sectional view of the prior art portlight assembly of  FIG. 1A  in an open position; 
           [0022]      FIG. 2A  is a partial cross sectional view of a present invention portlight assembly in a closed position having a known gasket orientation; 
           [0023]      FIG. 2B  is a partial cross sectional view of the present invention portlight assembly of  FIG. 2A  in an open position; 
           [0024]      FIG. 3A  is a partial cross sectional view of yet another prior art portlight assembly in a closed position; 
           [0025]      FIG. 3B  is a partial cross sectional view of the prior art portlight assembly of  FIG. 3A  in an open position; 
           [0026]      FIG. 4  is a partial cross sectional view of still yet another prior art portlight assembly; 
           [0027]      FIG. 5  is a partial cross sectional view of another prior art portlight assembly; 
           [0028]      FIG. 6A  is a partial cross sectional view of an embodiment of a present invention portlight assembly in a closed position; 
           [0029]      FIG. 6B  is a partial cross sectional view of the present invention portlight assembly of  FIG. 6A  in an open position; 
           [0030]      FIG. 7A  is a partial cross sectional view of another embodiment of a present invention portlight assembly in a closed position; 
           [0031]      FIG. 7B  is a partial cross sectional view of the present invention portlight assembly of  FIG. 7A  in an open position; 
           [0032]      FIG. 8  is a front plan view of portlight including an embodiment of the present invention angled gasket; and, 
           [0033]      FIG. 9  is a cross sectional view of the portlight of  FIG. 8  taken generally along line  9 - 9 . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0034]    At the outset, it should be appreciated that like drawing numbers on different drawing views identify identical, or functionally similar, structural elements of the invention. While the present invention is described with respect to what is presently considered to be the preferred aspects, it is to be understood that the invention as claimed is not limited to the disclosed aspects. 
         [0035]    Furthermore, it is understood that this invention is not limited to the particular methodology, materials and modifications described and as such may, of course, vary. It is also understood that the terminology used herein is for the purpose of describing particular aspects only, and is not intended to limit the scope of the present invention, which is limited only by the appended claims. 
         [0036]    Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood to one of ordinary skill in the art to which this invention belongs. It should be appreciated that “clear viewing area” as used herein is intended to mean that the area within the lens through which a person may look is unobstructed by any hardware, objects, gaskets, etc., thereby permitting full use of that area for viewing. Furthermore, it should be appreciated that “undesirable shearing of the gasket” as used herein is intended to mean that the gasket is subjected to minimal shearing forces; however, as described supra, some small amount of shearing forces may still be applied to the gasket. Although any methods, devices or materials similar or equivalent to those described herein can be used in the practice or testing of the invention, the preferred methods, devices, and materials are now described. 
         [0037]    Recent design trends for portlights requires that the lens element be flush with the outer hull surface. Traditionally, such an arrangement could never be done, as traditional designs would not permit it, nor was it practical to put the glass or acrylic surface of the lens flush to the hull where is could be damaged, scratched or pressed inward by a fender or object mounted on the marine jetty. Regardless of such constraints, recent design trends require such a portlight. 
         [0038]    In addition to the design constraints described above, the following design requirements are also present under some circumstances: (1) a clear viewing area; (2) a small frame size; (3) hardware visually hidden by being inside the outer perimeter of the port; (4) a thin cross section of the port; (5) a hinge that sits directly over the gasket; and, (6) permit a flush lens to be made with a hinge pin inside the one-half inch width, for all the aforementioned reasons. 
         [0039]    It has been found that the foregoing design requirements can be met by arranging the sealing surfaces and sealing gasket of a portlight at an angle, e.g., an angle ranging from 30-60 degrees. An angle of 45 degrees is preferred; however, angles ranging from 30-60 degrees have been found to also satisfy the recent design requirements. It has been further found that angles shallower than 45 degrees, i.e., less than 45 degrees, on the hinge side begin to introduce the shearing situation described supra. However, a problem arises on the side opposite the hinge. If the gasket support surfaces were vertical, pure shear and minimal translation of the gasket support surfaces needed to generate the 20% compression of the gasket occurs. A gasket angle of 45 degrees averages the forces so that both sides get some compression, no tearing of the gasket occurs and both sides of the portlight, i.e., hinge side and the side opposite thereto, seal properly. 
         [0040]    It should be noted that the shearing and tearing of the gasket are minimized; however, such conditions are not entirely eliminated. Once the gasket is safely delivered to the mating sealing surface, there is some friction between the gasket and that surface which causes some “shearing” forces to be set up that simply cause the rubber to be pushed sideways. A “shearing” force actually does this, but it is irrelevant as the sealing surfaces of the gasket are in contact with the mating surfaces before this occurs. It has been found that the amount of movement or translation of the rubber is minimal and has no affect on the performance of the gasket, short term or long term. Moreover, gaskets do not have to include flat surfaces. It might be desirable to dome or curve the outer surface so the center of the gasket makes contact with the mating surface first, thereby further minimizing the “shearing” forces. 
         [0041]      FIGS. 2A and 2B  depict a present invention portlight hinge arrangement; however, the embodiment depicted in these figures does not include an angled gasket. Thus, one of ordinary skill in the art will appreciate the benefits of the present invention angled gasket in combination with the present invention portlight hinge arrangement shown in  FIGS. 2A and 2B . Portlight  30  includes surfaces  32  and  34  that support gasket  36 . Surfaces  32  and  34  are parallel with one another and parallel to lens element  38  when fully closed. Such an arrangement sets up a shearing situation with gasket  34 . Portlight  30  is arranged to be installed through vessel wall  40  from the outside of wall  40 . The portion of gasket  36  which is subject to shearing or tearing is shown by broken line portion  42  of gasket  36 . As can be appreciated in view of these figures, conventional gasket arrangements will not function with this embodiment of the present invention hinge arrangement without unacceptable shearing of the gasket. 
         [0042]      FIGS. 6A and 6B  shows an embodiment of a present invention angled gasket and hinge assembly, i.e., a similar hinge assembly as shown in  FIGS. 2A and 2B . In this embodiment, hinge  100  is positioned within port  101  and directly over lens support frame  102 . Such an arrangement was not previously possible as the hinge would have visible within the outer perimeter of the port. Port frame  104  comprises body  106  having flange  108  arranged to seal against the outer surface of vessel wall  110 . Body  106  further comprises sealing surface  112  and extension  114  whereon hinge  100  is secured. Hinge  100  comprises extension  116 , pin  118  and rotating element  120 . Rotating element  120  is fixedly secured to lens support frame  102 , while lens support frame  102  is in turn fixedly secured to lens  122 . In this embodiment, gasket  124  is secured to lens  122 ; however, gasket  124  could alternatively be secured to sealing surface  112 . As the assembly of rotating element  120 , lens support frame  102 , lens  122  and gasket  124  is rotated towards sealing surface  112 , surface  126  of gasket  124  approaches surface  112  substantially perpendicularly which results in minimal shearing forces. As can be seen in the figures, sealing surface  112  and surface  126  of gasket  124  are disposed at angle α relative to outer surface  128  of body  106 . As described supra, angle α may range between 30 degrees and 60 degrees, and is preferably approximately 45 degrees. 
         [0043]    Another embodiment of a present invention angled gasket and hinge assembly is shown in  FIGS. 7A and 7B . This embodiment may take the form of a plastic, stamped stainless steel, or extruded aluminum port that includes an internal trim ring which may be used to clamp the port light onto the hull surface to aid a builder in the installation process. In this embodiment, port  150  comprises hinge  152 . Unlike the previous embodiment, hinge  152  is positioned above port frame  154  and not positioned within port  150  or directly over lens  156 . Port frame  154  comprises body  158  having flange  160  arranged to seal against the outer surface of vessel wall  162 . Body  158  further comprises sealing surface  164  and extension  166  whereon hinge  152  is secured. Hinge  152  comprises extension  168 , pin  170  and rotating element  172 . Rotating element  172  is fixedly secured to lens  156  by securing portion  174  of rotating element  172  via screw  176  and insert  178 . In this embodiment, gasket  180  is secured to lens  156 ; however, gasket  180  could alternatively be secured to sealing surface  164 . As the assembly of rotating element  172 , lens  156  and gasket  180  is rotated towards sealing surface  164 , surface  182  of gasket  180  approaches surface  164  substantially perpendicularly which results in minimal shearing forces. Similar to the embodiment shown in  FIGS. 6A and 6B , sealing surface  164  and surface  182  of gasket  180  are disposed at an angle relative to outer surface  184  of body  158 . As described supra, the angle may range between 30 degrees and 60 degrees, and is preferably approximately 45 degrees. 
         [0044]    It should be appreciated that an embodiment of the present invention includes an internal trim ring, e.g., trim ring  186 . In some embodiments, trim ring  186  is independent of port base frame  154 . In other words, trim ring  186  may be purely decorative. Alternatively, in other embodiments, trim ring  186  screws into the port base frame, e.g., port frame  154 , and draws the trim ring and base frame together. 
         [0045]    It should be further appreciated that the arrangement of the present invention portlight permits the substantial coplanar positioning of the outer surface of the port lens and the outer surface of the vessel. Positioning the sealing gasket at an angle relative to the foregoing outer surfaces decreases the offset of the gasket from the sealing surface in the direction from the outer surface and the inner surface. In other words, the known gasket arrangements result in the lens being offset by an amount equal to the thickness of the gasket, while the present invention angled gasket results in the lens being offset by an amount that is less than the thickness of the gasket, i.e., the fraction of the thickness based on the angle of the gasket position. 
         [0046]      FIGS. 8 and 9  depict a portlight having the present invention angled gasket arranged therein. Portlight  200  includes trim ring  202 , lens  204 , hinge  206  and dogs  208 . As one of ordinary skill in the art will appreciate dogs  208  are used to securely hold lens  204  against gasket  210 . As can be seen in  FIG. 9 , portlight  200  is secured within vessel wall  212  via port frame  214  and trim ring  202 . As can be further appreciated in view of  FIG. 9 , outer surface  216  of lens  204  is substantially coplanar with outer surface  218  of vessel wall  212 . Moreover, the sealing surface of lens  204  forms an angle ranging from about 120 degrees and about 150 degrees, i.e., angle β. Thus, the combination of angle α and angle β results in a value of approximately 180 degrees. 
         [0047]    One of ordinary skill in the art will appreciate that the foregoing present invention portlight arrangements permit the reduction in size of the portlight frame. In other words, by permitting the positioning of the hinge within the portlight without obscuring the portlight&#39;s viewable area, the overall frame size may be reduced. Furthermore, the present invention portlight arrangement permits the outer surface of the port lens to be substantially coplanar with the outer surface of the vessel wall. 
         [0048]    Thus, it is seen that the objects of the present invention are efficiently obtained, although modifications and changes to the invention should be readily apparent to those having ordinary skill in the art, which modifications are intended to be within the spirit and scope of the invention as claimed. It also is understood that the foregoing description is illustrative of the present invention and should not be considered as limiting. Therefore, other embodiments of the present invention are possible without departing from the spirit and scope of the present invention.