Abstract:
A sealing arrangement comprising a channel-shaped mounting portion which includes a support member supporting a seal portion. A covering covers the seal portion and a portion of both the mounting portion and the support member. The support member includes a metal reinforcement for preventing wrinkling of the seal portion at bends of the sealing arrangement. The sealing arrangement further includes an anisotropic web made of a textile or similar material which connects the mounting portion to the support member to counteract the forces of gravity on the seal portion. The web is more stretchable in a longitudinal direction of the web than in a lateral direction of the web.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The invention relates to a longitudinally extending sealing arrangement for disposal between a closure member and a closable opening comprising a surround having a length, the sealing arrangement comprising a mounting portion adapted for mounting the sealing arrangement on the surround of the closable opening, and a longitudinally extending sealing portion of hollow tubular form defining an interior volume, the sealing portion being carried by and alongside the mounting portion and being adapted to run along at least part of the length of the surround when the mounting portion is mounted on the surround and to be sealingly compressed by the closure member for the opening. 
   2. Description of Related Art 
   Such an arrangement is shown for example in U.S. Pat. No. 6,442,902 (Van den Oord) and U.S. Pat. No. 5,493,814 (Christian). The invention aims to provide an improved arrangement with the possibility of greater flexibility. 
   BRIEF SUMMARY OF THE INVENTION 
   According to the invention, therefore, the sealing portion in the sealing arrangement referred to above is carried by and alongside the mounting portion by longitudinally extending flexible support means running alongside the mounting means and attached to a linear first region of the mounting means which runs along its length in a predetermined position thereon, the flexible support means extending transversely to its length from said region and being attached to the sealing portion exteriorly to the interior volume of the sealing portion, said flexible support means being flexible to allow the sealing portion to move angularly towards and away from the mounting portion as the flexible support means flexes, and the sealing arrangement also includes a web-shaped connecting member extending along the length of the sealing arrangement, the web-shaped connecting member being attached to the mounting portion along a linear second region of the mounting means which is substantially parallel to and spaced from said first region, the web-shaped connecting member extending from said second region into attachment with the sealing portion to interconnect the sealing portion and the mounting portion, the web-shaped connecting member extending between a location on the sealing portion exteriorly of said internal volume thereof and the second region on the mounting portion, the web-shaped connecting member comprising material which is relatively stretchable in the longitudinal direction of the sealing arrangement, said material being relatively compressible widthwise but resistant to widthwise stretching, whereby the web-shaped connecting member limits the extent of angular movement of the sealing portion away from the mounting portion as the flexible support means flexes. 
   According to the invention, there is also provided a sealing arrangement for sealing around an opening in a motor vehicle body which is closable by a closure member, the opening having a surround, the sealing arrangement comprising a channel-shaped mounting portion made of flexible and resilient material adapted to embracingly grip the surround of the opening, the channel of the mounting portion having a base and first and second side walls, a soft resilient and flexible seal extending longitudinally along the sealing arrangement and made of flexible and resilient material, a web-shaped strip of fabric, a flexible support member extending longitudinally along the sealing arrangement and projecting from the base of the channel of the mounting portion and incliningly outward away from the outside of said first side wall of the channel, the flexible support member defining a first surface facing away from the mounting portion and a second surface facing the outside of said first side wall of the channel, the seal being mounted on said first surface and thereby supported by the flexible support member to be movable angularly towards and away from the mounting portion by flexing of the support member and so as to be sealingly compressed by the closure member, and a skin-like covering extending from the outside of the mounting portion over the outside of the seal and extending partially over the support member on said second surface thereof but being clear of that side wall, the web-shaped strip of fabric interconnecting the outside of the first channel wall at a position displaced from the base of the channel of the mounting portion and the second surface of the support member, the web-shaped strip extending along the length of the sealing arrangement and being longitudinally stretchable and readily compressible widthwise, the web-shaped strip being resistant to width-wise stretching so as to limit the extent of the angular movement of the seal away from the mounting portion as the support member flexes. 
   DETAILED DESCRIPTION OF THE DRAWINGS 
   Sealing arrangements embodying the invention will now be described, by way of example only, with reference to the accompanying diagrammatic drawing which is a diagrammatic cross-section through one of the sealing arrangements. 

   DETAILED DESCRIPTION OF THE INVENTION 
   The sealing arrangement shown in the FIGURE comprises a longitudinally extending channel-shaped mounting or gripping portion  10  which supports a similarly extending. hollow tubular sealing portion  12 . The sealing arrangement is preferably produced by extrusion, but any other suitable process, such as moulding, may be used instead. The sealing arrangement is made of suitable plastics or rubber material and is preferably made from a thermoplastic elastomer. The gripping portion  10  comprises material defining opposite side walls  14 , 16  integral with a base  18 . Preferably, a channel-shaped reinforcing core or carrier  20  is embedded in the extruded material of the side walls  14 , 16  and the base  18 . Carrier  20  may be made of any suitable preferably resilient material, advantageously metal. It may comprise metal in the form of an unslit or slit channel, or it may comprise a series of U-shaped elements (inverted in the view shown in the FIGURE) which are arranged side by side along the length of the channel to define the channel and are either entirely disconnected from each other or integrally connected by flexible connecting links. Instead, looped wire may be used. Other forms of carrier can be used instead. 
   The carrier  20  is preferably incorporated in the material of the gripping portion  10  by a cross-head extruder process. 
   As shown in the FIGURE, channel  14  is formed with two longitudinal ridges  22 , 24 , and the side wall  16  is formed with two longitudinal lips  26 , 28  which extend substantially across the width of the channel. 
   To increase the resilience of the gripping portion  10 , and to reduce its weight, the material of the base  18  of the gripping portion may incorporate a longitudinally extending hollow chamber  30 . 
   The material of the gripping portion is extended sideways from the base  18  to form a lip  32  which extends along the length of the sealing arrangement and is curved over towards the outside of the side wall  16 . Lip  32  is a so-called “cosmetic lip” for a purpose to be described. 
   On the opposite side of the channel of the gripping portion  10 , side wall  14  integrally carries a support member or lip  34 . The support lip  34  preferably incorporates a reinforcing member  36  which extends along the length of the sealing arrangement and also extends substantially to the distal end of the lip  34 . 
   As shown in the FIGURE, a longitudinally extending tubular seal  38  is supported on the support lip  34 . The tubular seal  38  may be produced separately from the remainder of the sealing arrangement. 
   The tubular seal  38  may be softer and more flexible than the remainder of the extruded material, and may, for example, be spongy or of cellular construction. 
   In use, the gripping portion  10  is embracingly mounted on the flange which extends around the door opening on a motor vehicle body, where the inner and outer body panels are welded together. This flange is shown diagrammatically at  40  in the FIGURE. When the gripping portion  10  is forced onto the flange  40 , the ends of the lips  26 , 28  bear against one side face of the flange, and the ridges  22 , 24  bear against the opposite side face thereof. In this way, and aided by the resilient of the carrier  20 , the gripping portion  10  is securely mounted on the flange  40  and supports the sealing portion  12  so that it runs around the periphery of the opening, lying on the outside thereof. The closing door for the opening thus partially compresses the tubular seal  38  to form a weather-tight seal around the closed door opening. The material of the integral lips  26 , 28  of the gripping portion  10  may be softer than the remainder of the channel-shaped material. This increases the co-efficient of friction of the material, and helps to secure the gripping portion  10  securely on the flange. 
   The cosmetic lip  32  becomes positioned on the inside of the vehicle body, around the door opening, and can be used to hide the edge of a trim panel. 
   The use of thermoplastic elastomer material for the sealing arrangement is advantageous because of its very low weight, ease of manufacture, and recyclability. The thermoplastic elastomer material of the tubular seal  38  is preferably of soft open-cellular form. In order to protect it against ingress of moisture, it is covered with a co-extruded skin  42  which may be of closed-cellular form (but otherwise of similar material). 
   In order to provide good sealing, it is desirable that the material of the tubular seal  38  should be very soft and flexible. In this way, it can provide effective sealing even if there are discontinuities or variations in the thickness of the flange  40 . Soft material is also advantageous because it may be of cellular form and therefore light in weight. However, it is necessary for the sealing arrangement to be bent to follow curves or corners in the door frame. When bent in this way, there will therefore be a tendency for the sealing portion  12  to become wrinkled at the curves or corners as the sealing arrangement is bent around the frame—with the mouth of the channel of the gripping portion  10  facing radially outwardly of the curve or corner. The softer is the sealing portion  12 , the greater will this wrinkling tendency be. The purpose of the reinforcement  36  in the support lip  34  is to eliminate or reduce this wrinkling tendency. The reinforcement may comprise a length of looped wire of generally zig-zag configuration, or a thin metal sheet with longitudinally extending generally parallel grooves. The reinforcement  36  is designed to be relatively compressible in the “width” direction, that is relatively compressible in response to forces acting between points A and B, but relatively stiff to forces acting in the direction of the arrow C, that is, generally perpendicular to the major plane of the lip  34 . The incorporation of the reinforcement  36  helps to reduce or substantially eliminate any tendency of the tubular seal  38  to wrinkle at, or bridge across, bends or curves in the mounting flange—but at the same time it does not reduce the effective softness of the sealing portion  12  in response to the closing door. 
   The skin  42  extends not only over the outside of the tubular seal  38  but also extends over part of the outside surface of the gripping portion  10  and lies in a recess  44 . Its opposite edge extends over the underside of the support lip  34  for about half its length, to terminate along a line D. The skin  42  thus helps to hold the tubular seal  38  on the support lip  34 . 
   It will be appreciated that the orientation of the sealing arrangement when mounted along the horizontal top run of the door frame will be inverted as compared with the orientation shown in the FIGURE. There will therefore be a tendency for the support lip  34  and the tubular seal  38  to flex outwardly in the general direction of the arrow E, in response to the effect of gravity. This is unsatisfactory because the sealing portion  12  may assume a position which is not correct for optimum sealing when the door closes onto it. In order to prevent this, therefore, a flexible web  46  extends between an anchorage point  48  on the inner face of the support lip  34  and an anchorage point  50  on the outside of the side wall  14  of the channel of the gripping portion  10 , adjacent its mouth. This web may be of textile or fabric form and is anisotropic. More specifically, it is longitudinally stretchable (that is, stretchable in the direction of the sealing arrangement) but is resistant to width-wise stretching (that is, in the direction extending between the support lip  34  and the side wall  14  of the gripping portion  10 ). In this way, therefore, the web  46  does not impair the longitudinal flexibility of the sealing arrangement but firmly prevents outward movement of the tubular seal in the direction of the arrow E. However, the fabric of the web  46  is readily compressible in the width-wise direction, and it therefore does not impair the compressibility of the sealing arrangement in response to the closing door. More specifically, the use of a textile or fabric anisotropic web  46  is advantageous as compared with alternative arrangements in which the web  46  is omitted but, instead, the skin  42  bridges across the gap between the support lip  34  and the side wall  14  of the gripping portion  10 . Such an alternative arrangement reduces the compressibility of the sealing portion  12  because of the relative stiffness of the skin  42 .