Abstract:
The invention provides a cap for a container for storing condiments for human consumption. The cap comprises a member having a top portion with a peripheral wall that has means for retaining the cap onto the container extending downwardly for covering the mouth of the container, the top portion having dispensing openings for allowing passage of the condiments. The cap comprises a seal having a top portion comprising a central portion, a flange portion extending around the central portion for overlapping the dispensing openings of the member and a central peripheral wall extending downwardly from the top portion and having a lower end mountable to the member. In use, the seal is moveable between a closed position, wherein the flange portion covers the dispensing openings for preventing passage of the condiments outwards from the interior of the container, and an open position, wherein the flange portion and the flange portion frees the dispensing openings for allowing passage of the condiments outwards from the interior of the container.

Description:
FIELD OF THE INVENTION 
     The present invention relates to a cap for a condiment container. 
     BACKGROUND OF THE INVENTION 
     Condiment containers such as salt shakers traditionally have caps with dispensing openings provided therein to allow the escape of condiments through the cap when the container is inverted. The condiment container can thus be used to spread condiments over, e.g., a meal by inverting the container over the meal to allow the condiment from escaping through the cap onto the plate. 
     With condiment containers that have exposed dispensing openings, condiments may escape accidentally if the container is tilted or tipped unwillingly. Furthermore, the open dispensing openings allow the entry of humidity, dust and other impurities into the condiment container which may soil the condiments. As such, caps for condiment containers that provide a closing mechanism are preferred to those that do not. 
     U.S. Pat. No. 5,597,096 provides a shaker for condiments with a cap that can open and close. The cap has an arcuate form and can be opened by a user by pressing on the apex of the form. When opened, the cap arches upwards and reveals dispensing openings. This cap, however, suffers from multiple drawbacks. For example, it is only mountable on a shaker having an integral mounting bead along the mouth. 
     In the context of the above, it can be appreciated that there is a need in the industry for an improved cap for a condiment container. 
     SUMMARY OF THE INVENTION 
     In accordance with a first broad aspect, the present invention provides a cap for a container defining an interior for storing condiments for human consumption and having an upper portion defining a mouth. The cap comprises a member having a top portion with a peripheral wall extending downwardly for covering the mouth of the container, the peripheral wall having means for retaining the cap onto the container, the top portion having a plurality of dispensing openings for allowing passage of the condiments. The cap further comprises a seal having a top portion comprising a central portion, a flange portion extending around the central portion for overlapping the dispensing openings of the member, and a central peripheral wall extending downwardly from said top portion and having a lower end mounted to the member. In use, the seal is moveable between a closed position, wherein the central portion is above the flange portion and the flange portion covers the dispensing openings of the member for preventing passage of the condiments outwards from the interior of the container, and an open position, wherein the central portion is below the flange portion and the flange portion frees the dispensing openings of the member for allowing passage of the condiments outwards from the interior of the container. 
     In accordance with a second broad aspect, the present invention provides a cap for a container defining an interior for storing condiments for human consumption and having an upper portion defining a mouth. The cap comprises a member having an inner portion and an outer portion, the inner portion having a top portion with a peripheral wall extending downwardly for covering the mouth of the container, the peripheral wall of the inner portion having means for retaining the cap onto the container, the top portion of the inner portion having a plurality of openings for allowing passage of the condiments, the outer portion having a top portion with a peripheral wall extending downwardly for covering at least partially the peripheral wall of the inner portion, the top portion of the outer portion having a plurality of dispensing openings for allowing passage of the condiments outwards from the interior of the container. The cap further comprises a seal having a top portion comprising a central portion, a flange portion extending around the central portion for overlapping the dispensing openings, and a central peripheral wall extending downwardly from said top portion and having a lower end mounted to the member. In use, the seal is moveable between a closed position, wherein the central portion is above the flange portion and the flange portion covers the dispensing openings of the outer portion for preventing passage of the condiments outwards from the interior of the container, and an open position, wherein the central portion is below the flange portion and the flange portion frees the dispensing openings for allowing passage of the condiments outwards from the interior of the container. 
     In accordance with a third broad aspect, the present invention provides a cap for a container defining an interior for storing condiments for human consumption and having an upper portion defining a mouth. The cap comprises a member having an inner portion and an outer portion, the inner portion having a top portion with a peripheral wall extending downwardly for covering the mouth of the container, the peripheral wall of the inner portion having means for retaining the cap onto the container, the top portion of the inner portion having a plurality of openings for allowing passage of the condiments, the outer portion having a top portion with a peripheral wall extending downwardly for covering at least partially the peripheral wall of the inner portion, the top portion of the outer portion having a central opening encircling a vertical axis of the cap and a plurality of dispensing openings for allowing passage of the condiments outwards from the interior of the container. The cap further comprises a seal having a top portion comprising a central portion, a flange portion extending around the central portion for overlapping the dispensing openings, and a central peripheral wall extending downwardly from a peripheral live hinge, passing through the central opening of the outer portion and having a lower end mounted to the member, the seal being in a closed position when the flange portion covers the dispensing openings of the outer portion for preventing passage of the condiments outwards from the interior of the container and the seal being in an open position when the flange portion frees the dispensing openings of the outer portion for allowing passage of the condiments outwards from the interior of the container; wherein, in use, when the seal is in the closed position and a user presses on the central portion, downward movement of the central portion below the peripheral live hinge imparts upward movement of the flange portion above the peripheral live hinge such that the seal is in the open position and the central portion is at least partially located within the central peripheral wall, and when the user presses afterwards on the flange portion, downward movement of the flange portion below the peripheral live hinge imparts upward movement of the central portion above the peripheral live hinge such that the seal returns in the closed position. 
     These and other aspects and features of the present invention will now become apparent to those of ordinary skill in the art upon review of the following description of specific embodiments of the invention and the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A detailed description of examples of implementation of the present invention is provided hereinbelow with reference to the following drawings, in which: 
         FIG. 1A  is a side elevation view of a cap in accordance with an embodiment, the seal being shown in a closed position; 
         FIG. 1B  is a cross-sectional view of the cap shown in  FIG. 1A ; 
         FIG. 2A  is a side elevation view of the cap shown in  FIG. 1A , the seal being shown in an open position; 
         FIG. 2B  is a cross-sectional view of the cap shown in  FIG. 2A ; 
         FIG. 3  is a top perspective view of the cap shown in  FIG. 1A , the seal being shown in the closed position; 
         FIG. 4  is a top perspective view of the cap shown in  FIG. 1A , the seal being shown in the open position; 
         FIG. 5  is a bottom perspective view of the cap shown in  FIG. 1A ; and 
         FIG. 6  is a cross-sectional of the seal of the cap shown in  FIG. 1A . 
     
    
    
     In the drawings, embodiments of the invention are illustrated by way of example. It is to be expressly understood that the description and drawings are only for purposes of illustration and as an aid to understanding, and are not intended to be a definition of the limits of the invention. 
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
       FIG. 1A  shows a cap  10  for a condiment container such as a salt shaker. In a non-limiting example, the cap is suitable for fastening to a container having an upper portion with a peripheral wall defining a mount and an interior for receiving condiments. 
     Unless explicitly or implicitly suggested otherwise, the various elements described herein are described from the perspective of a condiment container, such as a salt shaker, that is standing upright on a flat surface and onto which the cap is affixed at a top portion. As such, orientationally descriptive terms such as ‘upward’, ‘top’, ‘vertical’ or ‘upper’, will generally refer to this particular frame of reference. However, it should be understood that this orientation is used only as an example to facilitate understanding of the invention, but that the invention is not limited to any particular orientation of its elements. For example, although the mouth of the container described above is described as being defined at an upper portion of the container, it should be understood that the container could be reoriented or otherwise shaped such that the portion defining the mouth is no longer “up” without departing from the intended scope of the invention. 
     The cap  10  comprises a seal  12  and a member  14 . The member  14  comprises a top portion  16  and a peripheral wall  18  extending downwardly from the top portion  16 . In this exemplary view, the peripheral wall  18  is circular in cross-section; however it should be understood that the peripheral wall  18  of the member  14 , and indeed, all parts of the cap  10  and the cap  10  itself may vary in shape and size and that the invention is not intended to be limited to the particular shape shown in the figures. The cap  10  is suited for attachment to a condiment container at a mouth of the condiment container by any appropriate retaining mean. When the cap is attached to the container, the peripheral wall of the member is said to cover the mouth of the container. In a non-limiting example, the peripheral wall of the member has threads  92  and can be twisted onto a suitably threaded container, however the particular retaining means used is not meant to limit the invention and in any arrangement when the mouth of the container is covered by the cap, it is said that the peripheral wall of the member covers the mouth of the container. 
     The seal  12  comprises a top portion  20 , which is the only portion of the seal  12  visible in  FIG. 1A . The top portion  20  comprises a central portion  22  and an annular flange portion  24  extending around the central portion  22 . As best seen in  FIG. 3 , in this particular example, the seal  12  has a substantially circular circumference. 
     The central portion  22  is substantially circular and is surrounded by the flange portion  24 .  FIGS. 1A ,  1 B and  3  show the seal  12  in a closed position. In the closed position, the seal  12  adopts a substantially convex form, so called because from a perspective outside of the cap  10  and the container, the seal  12  swells outwards. At least an area  28  within the top portion  16  of the member  14  is covered by the seal  12  when the seal  12  is in the closed position. 
     As seen in  FIG. 4 , the area  28  is a peripheral surface which surrounds a central opening  40  provided in the member. The peripheral surface comprises a plurality of dispensing openings  30 . The dispensing openings  30  can be located anywhere on the member  14  but are preferably on the top portion  16  thereof and preferably still on the peripheral surface. When not blocked, the dispensing openings  30  allow the passage of condiments through the member  14 , for example from the interior of a container attached to the cap  10  outwards. The peripheral surface comprises a flat section  34 , an inclined section  36  and a crest  38 . The inclined section  36  extends upwardly from the flat section to the crest  38 . Although the flat section  34 , inclined section  36  and crest  38  are shown here as three discrete section, they can be merely portions of a continuum, and even infinitesimal such portions. For example, the flat section  34  and the inclined section  38  could form a continuous curve from the central opening  40  up to the crest  38 . Also, while the crest  38  is shown here as a circular peak, it should be understood that it could be any section of any shape located upwardly from the flat section  34 , such as a flat section extending outward from the inclined section  36  or even an inclined continuation of the inclined section  36 . 
     The area  28  is said to be covered or overlapped by the seal  12  because the seal  12  blocks it and makes it inaccessible. In this non-limiting example, the top portion  20  forms a seal around this area. It should be understood that it is not necessary for there to be direct contact between the seal and the area  28  for it to be considered covered. Rather, it must merely be blocked e.g. in such a manner that condiments cannot exit to the exterior through the dispensing openings  30 . As seen in  FIG. 1B , the top portion  20  rests against the crest  38  but leaves an open gap  42  above the inclined section  36  and the flat section  34 . Nevertheless, the gap  42 , flat section  34 , inclined section  36  and dispensing openings  30  are considered covered by the seal  12 , since they are blocked. For example, condiments such as salt cannot pass through the dispensing openings  30  and out away from the cap when the seal is in the closed position. Alternatively, the seal  12  could lay physically on the covered area  28 , leaving no gap between the seal  12  and the member  14  at the area  28 . 
     The flange portion  24  of the seal  12  comprises a lower peripheral end wall  80  for abutting against the member  14 . As shown in  FIG. 1B , when the seal  12  is in the closed position, the lower peripheral end wall  80  is generally horizontally flat, or aligned perpendicularly with a longitudinal axis  72  of the cap  10  and rests against the crest  38  for forming a seal for preventing exit of the condiments. As shown in  FIG. 2B , when the seal is in the open position, the lower peripheral end wall  80  is, along with the rest of the flange portion  24 , moved upwards from its closed-position location and no longer prevents passage of condiments outwards. The lower peripheral end wall  80  is aligned transversely with respect to the vertical axis  72  of the cap  10 , not perpendicularly but rather obliquely. 
     The flange portion  24  comprises on its lower surface an annular indentation  82  located radially interiorly of the lower peripheral end wall  80 . The annular indentation  82  is adjacent the lower peripheral end wall  80 . The annular indentation  82  may reduce resilience in the material in the flange portion  24 , which resilience may otherwise impede the seal  12  from adopting the closed position or the open position. 
       FIGS. 2A ,  2 B and  4  show the seal  12  in an open position. Here, the seal  12  adopts a substantially concave form, so called because it defines a depression visible from a perspective outside of the cap  10  and the container. When the seal  12  is in the open position, the area  28  of the top portion  16  of the member  14  is considered uncovered even though part of the seal  12  may lie physically above it because it is not blocked. 
     As mentioned above, the top portion  16  of the member  14  has the dispensing openings  30  located in the section  28  that is covered by the seal  12  when the seal  12  is in the closed position. As best seen in  FIG. 4 , grooves  32  are provided adjacent the dispensing openings  30 . The dispensing openings  30  are each located inside a respective groove  32 , each groove  32  extending outwards into the inclined section  36 . When the seal  12  is in the open position, and the container is tilted, condiments contained in the container escape through the dispensing openings  30  and are guided by the grooves  32  such that they flow directly outwards. When the container is returned to the upright position, any condiment remaining on the inclined section  36  is guided by the groove  32  back into the dispensing opening  30 , thus preventing the unsightly accumulation of condiment along the flat section  34 . While in this example each dispensing opening  30  is located in a respective groove  32 , it should be noted that many other configurations of grooves  32  and dispensing openings  30  are possible. For example, the dispensing openings  30  may be near, but not in, the grooves  32  and there may be multiple dispensing openings  30  to a groove  32 . 
     As best seen in  FIG. 2B , the seal  12  comprises a central peripheral wall  44  extending downwardly from the top portion  20  of the seal  12  at a peripheral live hinge  46 . In the example shown, the central peripheral wall  44  has a generally cylindrical shape however, other shapes are possible. The central peripheral wall  44  has a lower end  66  to be mounted to the member  14 . The peripheral live hinge  46  allows movement of the top portion  20  of the seal  12  with respect to the central peripheral wall  44 . The peripheral live hinge  46  defines an area of reduced thickness with respect to the central peripheral wall  44 , although any configuration providing adequate hinging could be used. The live hinge  46  connects the central peripheral wall  44  to the underside of the top portion  20  of the seal  12  around the periphery of central portion  22 . 
     As mentioned above, the top portion  20  of the seal  12  adopts a substantially concave form when in the closed position and a substantially concave form when in the open position. As seen in  FIGS. 1A and 1B , when the seal  12  is in the closed position, the flange portion  24  extends downwardly from the central portion  22 . As best seen in  FIG. 2B , when the seal  12  is in the open position, the flange portion  24  extends above the central portion  22  and the central portion  22  is located within the central peripheral wall  44 . 
     When a user presses on the central portion  22 , the central portion  22  moves downwards below the level of the live hinge  46 . As best seen in  FIG. 2B , the central portion  22  moves into the cylindrical form defined by the central peripheral wall  44  of the member. When the central portion  22  is pushed downwards, resilience in the material of the top portion  20  of the seal  12  causes the flange portion  24  to move upwards above the live hinge  46 . As a result, the top portion  20  of the seal  12  adopts the convex form characteristic of the open position of the seal  12 . In order to return the seal  12  to the closed position, a user moves the flange portion  24  downwards towards its closed-position arrangement. Resilience in the material of the top portion  40  of the seal  12  causes the central portion  22  to move upwards above the live hinge  46  and return to the open-position arrangement. 
     It should be noted that the central peripheral wall  44  and the peripheral live hinge  46  can be made of any suitable material and do not need to be of the same material as the top portion  20  of the seal  12 . For example, the central peripheral wall  44  and/or the peripheral live hinge  46  could be made of different materials, e.g. by overmolding. However, in the example shown here, the central peripheral wall  44 , live hinge  46  and top portion  20  of the seal  12  together form an integral piece made of a soft single flexible material with a good shape memory. For example, the seal can be made of injection molded silicone, compression molded silicone, thermoplastic rubber (TPR) or natural rubber. 
     The lower end  66  of the central peripheral wall  44  is affixed to the member  14  in an area adjacent the central opening  40 . Preferably, the central peripheral wall  44  may be affixed to the member  14  in such a way as to block or seal the central opening  40 , if present, such that condiments cannot pass through the central opening  40 . In the example shown, the central peripheral wall  44  passes through at least a part of the central opening  40  and the lower end  66  is held against a bottom surface of the member  14  such that condiment cannot escape through the central opening  40 . In this example, condiments can enter the cylindrical form of the central peripheral wall  40 , but then find no opening through which to escape to the exterior. The central peripheral wall  44  can be affixed to the member  14  by any suitable means. For example, the lower end  66  of the central peripheral wall  14  can be glued to the member  14  or held by friction. 
     The member  14  may be a single integral piece or may be made of two or more pieces. As best shown in  FIGS. 1B ,  2 B and  5 , the member  14  is made up of an inner portion  50  and an outer portion  52 . The inner portion  50  has a top portion  54  and a peripheral wall  56  that extends downwardly from the top portion  50 . In a non limiting example, the peripheral wall  56  of the inner portion  50  comprises threads  92  disposed on the inside thereof that match treads on the outside surface of the container for attaching the cap  10  thereto. 
     The outer portion  52  has a top portion  58  and a peripheral wall  60  that extends downwardly from the top portion  58  and may make up a portion of the peripheral wall  18  of the member  14 . In a non-limiting example, the peripheral wall  60  of the outer portion  52  covers at least partially the peripheral wall  56  of the inner portion, as shown in  FIGS. 1B and 2B . 
     The outer portion  52  comprises the dispensing openings  30 , the area  28  having the peripheral surface, the grooves  32  and the central opening  40 . As seen in  FIG. 5 , in order for condiments to be able to exit through member  14  at the dispensing openings  30 , the inner portion  50  comprises a plurality of openings  62  adjacent with the dispensing openings  30  of the outer portion  52 . It is not necessary for the openings  62  of the inner portion  50  to be similar in shape, size or quantity as the dispensing openings  30  of the outer portion, rather it is merely necessary for at least a portion of the dispensing openings  30  to be aligned with at least a portion of the openings  62  such that condiments can flow out through the member  14 . As seen in  FIG. 5 , the openings  62  of the inner portion  50  are much larger than the dispensing openings  30  of the outer portion, each being aligned with four dispensing openings  30 . 
     In the example where member  14  is made of the inner and outer portions  50 ,  52 , a central opening  64  could be provided in the inner portion  50 , as shown in  FIGS. 1B and 2B . The central opening  64  is generally circular and encircles the vertical axis  72  of the cap  10 . The central opening  64  may allow passage of air downward into the container and out through the dispensing openings  30 . Thus, as the central portion  22  of the seal  12  is being pushed downwards to move the seal  12  from the closed position to the open position, the air occupying the space enclosed between the central portion  22 , the central peripheral wall  44  and the member  14  can escape through the central opening  64 , thus avoiding an increase in pressure that would resist the downward motion of the central portion  22 . Likewise, the air flow enabled by the central opening  64  also facilitates movement of the seal  12  from the open position to the closed position by preventing a decrease of pressure that would result from moving the central portion  22  upwards and increasing the volume of space between the central portion  22 , the central peripheral wall  44  and the member  14 , which decrease in pressure would resist the movement of the central portion  22  upwards. It should be appreciated however, that it is not necessary to provide central opening  40 , and that other means could be provided for allowing airflow. For example, holes in the top portion of the seal could be provided. 
     The central peripheral wall  44  passes through the central opening  40  of the outer portion  52 . The central peripheral wall  44  has a peripheral ring  68  at the lower end  66 . The peripheral ring  68  can be a simple enlargement of the diameter of the central peripheral wall  44  or any other form that projects radially outwards therefrom. The term peripheral “ring” is used here because in this non-limiting example the central peripheral wall  44  is cylindrical and the peripheral ring  68  follows the contour of the central peripheral wall  44 , thus defining a ring-like shape. However it should be understood that the peripheral ring  68  can be any form that projects outwards from the central peripheral wall  44 , not necessarily following the shape of the central peripheral wall  44  which in any case does not necessarily have to be cylindrical in form. While the peripheral ring  68  is disposed around the periphery of central peripheral wall  44  at the lower end, it does not necessarily need to follow the entire periphery of central peripheral wall  44 , and may be present only on a section or sections thereof. 
     As shown in  FIGS. 1B and 2B , the central peripheral wall  44  passes through the central opening  40  of the outer portion  52  and rests against the inner periphery of the central opening  40 . The peripheral ring  68  is below the outer portion  52  and projects radially outwards beyond the central opening  40 . As such, the peripheral ring  68  abuts against a bottom surface  70  of the top portion  58  of the outer portion  52  and prevents movement of the seal  12 . In addition, the top portion  54  of the inner portion  50  rests against the peripheral ring  68  from beneath, such that the peripheral ring  68  is sandwiched between the bottom surface  70  of the top portion  58  of the outer portion  52  and the top portion  54  of the inner portion  50 . The seal  12  is thus securely held in place with respect to the member  14 . 
     As seen in  FIGS. 1B ,  2 B and  6 , the peripheral ring  68  can include one or more projection  90  with a hole  86 . The projection  90  may project radially outwards beyond the rest of the peripheral ring  68  and may receive within the hole  86  a pin  88  projecting downwardly from the outer portion  52 . Where the peripheral ring  68  is sandwiched between a bottom surface  70  of the top portion  58  of the outer portion  52  and the top portion  54  of the inner portion  50 , the hole  86  receives the pin  88  projecting downwardly from the bottom surface  70 . Four projections  90  can be included in the peripheral ring  68  located at four equidistant points on the peripheral ring  68 ; although more or less projections  90  could be provided. For each projection  90 , a pin  88  is provided on the outer portion  52  so as to align with the projection  90 . Optionally, in the top portion  54  of the inner portion  50 , holes  84  are provided to accommodate the respective pins  88 , such that each pin  88  can pass through the respective holes  86 ,  84  (see  FIGS. 1B ,  2 B and  5 ). Although the pin  88  was described as projecting downwards from the bottom surface  70  of the top portion  58  of the outer portion  52 , it will be readily appreciated that the pin  88  could equally project upwards from the top portion  54  of the inner portion  50  and that accordingly, corresponding hole could be located in the outer portion  52 . Alternatively in the non-limiting embodiment where the member  14  is made of a single piece, pins projecting downwardly from the bottom surface of the member  14  can be received in the respective holes  86  of the seal  12 . Advantageously, the projection  90  and pin  88  combination impedes rotational motion of the seal  12  relative to the member  14 . 
     The central opening  40  of the outer portion  52  overlaps at least partially the central opening  64  of the inner portion  50  so that air can flow as described above. Optionally, the top portion  54  of the inner portion  50  comprises a projection  74  extending upwardly inside the volume enclosed by the central peripheral wall  44  of the seal  12 . Preferably, the projection  74  follows at least partly the inner contour of central peripheral wall  44 . The projection  74  may rest against the interior surface of central peripheral wall  44  and so hold the central peripheral wall  44  against the inner periphery of central opening  40  of the outer portion  52 , as best shown in  FIGS. 1B and 2B . The projection  74  extends upwards past the top portion  58  of the outer portion  52  and supports the central peripheral wall  44 . 
     The inner portion  50  and the outer portion  52  can be connected in any suitable manner. Their connection can be permanent or releasable. For example, they can be glued together. In another example, the inner portion  50  and the outer portion  52  are held together by friction-fit arrangement. 
     A protrusion and a complementary recess combination can be provided on the inner portion and outer portion to prevent movement of the inner portion and outer portion relative to one another in the vertical direction. The protrusion and complementary recess can follow the curvature of the inner and outer portions  50 ,  52  respectively and impede translational movement of the inner portion  50  relative to the outer portion  52  along the vertical axis. Additional protrusions and complementary recesses can be provided to prevent other motion between the inner and outer portions  50 ,  52 . Vertical protrusions extending vertically along the interior surface of the outer portion and complementary vertical recesses extending vertically along the exterior surface of the inner portion can be provided. Four such vertical protrusions and corresponding complementary recess combinations can be provided along the contour of the respective inner and outer portions  50 ,  52 , each of which can be aligned with the hole  84  of the inner portion  50  which may facilitate visual alignment of the inner portion  50  with the outer portion  52  for insertion therein. Vertical protrusions and corresponding complementary recesses may prevent rotational motion of the inner portion  50  relative to the outer portion  52 , particularly when twisting the cap  10  on or off a container. It will be appreciated that these protrusions and complementary recesses could be inverted, the protrusions being on the inner portion  50  and the complementary recesses on the outer portion  52 . 
       FIG. 6  is a cross-sectional view of a seal  12  with various thicknesses of materials indicated. The table below indicates the values of dimensions referred to by the variables in  FIG. 6 . The entries in the table indicate a range of possible values for each variable and at least one preferred value. 
     
       
         
               
               
               
             
               
               
               
               
             
               
               
               
               
             
           
               
                   
                   
               
               
                   
                 Range 
                 Preferred 
               
             
          
           
               
                 Variable 
                 Lower End (mm) 
                 Upper End (mm) 
                 Value (mm) 
               
               
                   
               
             
          
           
               
                 A 
                 4.70 
                 5.80 
                 5.25 
               
               
                 B 
                 3.00 
                 5.00 
                 3.53 
               
               
                 C 
                 1.30 
                 1.65 
                 1.48 
               
               
                 D 
                 3.29 
                 4.00 
                 3.65 
               
               
                 E 
                 4.00 
                 5.00 
                 4.54 
               
               
                 F 
                 1.20 
                 1.50 
                 1.35 
               
               
                 G 
                 2.45 
                 3.05 
                 2.75 
               
               
                 H 
                 1.35 
                 1.75 
                 1.55 
               
               
                 I 
                 1.10 
                 1.35 
                 1.20 
               
               
                 J 
                 0.35 
                 0.45 
                 0.40 
               
               
                 K 
                 12.55 
                 15.40 
                 13.97 
               
               
                 L 
                 11.10 
                 13.55 
                 12.3 
               
               
                 M 
                 9.65 
                 11.85 
                 10.73 
               
               
                 N 
                 7.55 
                 9.35 
                 8.46 
               
               
                 O 
                 7.20 
                 8.80 
                 8 
               
               
                 P 
                 0.70 
                 0.90 
                 0.80 
               
               
                 Q 
                 8.30 
                 10.20 
                 9.25 
               
               
                 R 
                 21.05 
                 25.80 
                 23.43 
               
               
                 S 
                 21.5 
                 27.5 
                 24.04 
               
               
                 T 
                 20.85 
                 25.55 
                 23.22 
               
               
                 U 
                 0.60 
                 0.80 
                 0.70 
               
               
                   
               
             
          
         
       
     
     Note that the seal can have an external diameter of between 30 millimeters and 60 millimeters. These dimensions are in no way intended to limit the invention. 
     Although various embodiments have been illustrated, this was for the purpose of describing, but not limiting, the invention. Various modifications will become apparent to those skilled in the art and are within the scope of this invention, which is defined more particularly by the attached claims.