Abstract:
Bottle opener for opening a bottle closed with a screw cap, in particular a wine bottle, wherein the bottle opener includes an annular contact element ( 1 ) having an inside surface ( 2 ) for resting against the screw cap, wthe inside surface ( 2 ) delimits a receiving cavity ( 3 ) for receiving the screw cap, and the inside surface ( 2 ) is delimited by two, preferably circular, edges ( 4, 4 ′) of the contact element ( 1 ) and the diameter ( 5 ) of the receiving cavity ( 3 ) delimited by the inside surface ( 2 ) decreases at least sectionally, starting from at least one of the edges ( 4 ) in the direction toward the other edge ( 4 ″), and a counter-clockwise internal thread ( 6 ) is formed on the inside surface.

Description:
BACKGROUND 
       [0001]    The invention relates to a bottle opener for opening a bottle closed with a screw cap, particularly a wine bottle. 
         [0002]    In recent years, more and more wine bottles have entered the market, which are no longer closed with the traditional cork but rather with a screw cap. On the one hand, this is more hygienic, on the other hand, the screw cap guarantees a safe and also long lasting air-tight seal of the wine bottles, which is not always ensured in the traditional cork. 
         [0003]    In particularly in restaurants, there is the need for bottle openers, which allow opening wine bottles with a screw cap, or other bottles provided with a screw cap, in an elegant and reliable fashion, requiring as little force as possible. 
       SUMMARY 
       [0004]    This objective is attained according to the invention in the bottle opener comprising an annular contact element with an inside surface to contact the screw cap, with the inside surface delimiting a receiving cavity to accept the screw cap and the inside surface being delimited by two preferably annular edges of the contact element, and the diameter of the receiving cavity delimited by the inside surface tapering sectionally beginning at least at one of the edges in the direction towards the other edge and the inside surface being embodied as a counter-clockwise internal thread. 
         [0005]    A contact element embodied in this fashion allows a reliable and also low-force removal of a screw cap from the bottle, particularly a wine bottle. Here, the bottle opener can be placed onto the screw cap at different angles, without risking that the attempt to open the bottle might fail. The bottle opener according to the invention therefore requires no particularly precise placement of the screw cap. By the combination of the features of a diameter of the inside surface and/or the receiving cavity delimited thereby reducing in one direction with the counter-clockwise thread inserted into the inside surface a high operating comfort is yielded and a secure opening of the bottle. 
         [0006]    Upon placement of the bottle opener onto the screw cap, first the internal thread of the bottle opener cuts into the screw cap when the operator begins to turn the bottle opener in the normal opening direction of a screw cap. This way, after a relatively small rotational angle a good lasting connection is produced between the bottle opener and the screw cap. When the bottle opener is then simply turned further in the same direction, the screw cap is screwed off the bottle. The fastening of the bottle opener to the screw cap as well as the unscrewing of the screw cap therefore occur both in the same direction of rotation, allowing a reliable and quick opening of the bottle. Even when such bottle openers, particularly in restaurants, are primarily intended for opening wine bottle, of course any other bottle comprising a screw cap can also be opened therewith in a simple and quick fashion. 
         [0007]    Beneficial embodiments of the invention provide that the top of the internal threads of the inside surface are located on a rotation-symmetrical surface and/or that the roots of the internal threads of the inside surface are located on a rotation-symmetrical surface. In particular, it may be provided here that the top of the internal threads of the inside surface are located on a frustum surface and/or that the roots of the internal threads of the inside surface are located on a frustum surface. Extensive experiments have shown that it is beneficial for the internal thread to have a thread pitch and/or a so-called lead ranging from 0.1 mm/rotation to 0.4 mm/rotation, preferably from 0.2 mm/rotation to 0.27 mm/rotation. The thread depth, i.e. the depth of a convolution of the internal thread should beneficially range from 0.01 mm to 0.5 mm, preferably from 0.15 mm to 0.25 mm. During the tests performed it has shown that in case of deviations from the above-mentioned values either no reliable connection developed between the screw top and the bottle opener or the screw top was deformed by the internal thread to such an extent that an unscrewing of the screw top was hindered. 
         [0008]    In order for the internal thread to reliably cut into the screw top it is beneficial for the threads tops to be embodied with an acutely angled cross-section. The roots of the threads however may have a rounded cross-section. 
         [0009]    Beneficially the annular contact element is formed from metal, at least in the area of the inside surface and the internal thread, but preferably in its entirety. For the production of the contact element the use of steel is particularly beneficial and here especially stainless steel. 
         [0010]    In order to prevent the contact element and/or the bottle opener from being accidentally placed in the wrong manner onto the screw cap to be opened, preferred embodiments of the invention provide that the diameter of the receiving cavity, delimited by the inside surface, at least partially tapers beginning at each of the edges in the direction to the respectively other edge. Such variants may be embodied essentially symmetrical in reference to a central level, at least concerning the progression of the diameter of the inside surface and/or the receiving cavity. In such embodiments it is beneficially provided that a minimal diameter of the receiving cavity, limited by the inside surface, is located in the middle between the edges. Particularly for screw caps common for wine bottles it is beneficial for the diameter of the receiving cavity, delimited by the inside surfaces, to amount to a value ranging from 30 mm to 30.5 mm at one edge, preferably at both edges of the contact element. The minimal diameter of the receiving cavity delimited by the inside surface ranges in preferred embodiments of the invention from 28 mm to 29 mm. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]    Additional features and details of preferred embodiments of the invention are explained using the description of the figures. Shown here are: 
           [0012]      FIG. 1  an exemplary embodiment of a bottle opener according to the invention, 
           [0013]      FIG. 2  a top view from the direction of the longitudinal central axis of the annular contact element of said bottle opener, 
           [0014]      FIG. 3  the detail A of  FIG. 2 , 
           [0015]      FIG. 4  a longitudinal cross-section through the annular contact element of the bottle opener according to  FIG. 1 , 
           [0016]      FIG. 5  an alternative embodiment of an annular contact element, and 
           [0017]      FIG. 6  the detailed views B of  FIGS. 4 and 5 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0018]      FIG. 1  shows a perspective view of a bottle opener embodied according to the invention. The contact element  1  is here made from stainless steel, in the present case arranged centrally in a handle part  20 . In the exemplary embodiment shown the handle part  20  is embodied disk-shaped, at least sectionally, and may e.g. be made from wood. Of course, this is only an example. The essential technical effect of the handle part  20  is the increase of the torque by enlarging the distance of the part of the bottle opener, at which it is grasped, from the longitudinal axis  17 . For reasons of completeness it shall be pointed out that the handle part  20  may also have any other suitable shape. In the exemplary embodiment shown, a recess  21  is provided at the exterior edge of the handle part  20 . This allows placing the bottle opener standing on its edge in the area of said recess  21 . 
         [0019]    The annular contact element  1  embodied according to the invention is arranged in a central recess of the handle part  20  of the bottle opener shown. It encompasses with its inside surface  2  the receiving cavity  3 , into which the screw cap to be removed, particularly from a wine bottle, can be inserted. According to the invention the inside surface  2  comprises, as shown according to the following figures, a diameter  5  sectionally tapering from one edge  4  of the contact element  1  in the direction towards the other edge  4 ′. Additionally, at the inside surface a counter-clockwise internal thread  6  is formed, i.e. an internal thread  6  threaded counter-clockwise. The depth of the thread  10  and the pitch  9  are embodied so small, however, that the internal thread  6  is only discernible in a detailed view. 
         [0020]    Optionally, as in the exemplary embodiment shown according to  FIG. 1 , notches  18  may be arranged in the inside surface  2 . They beneficially extend essentially parallel to the longitudinal central axis  17  and thus at an angle  19  ranging from 80° to 100°, preferably from 87° to 93°, in reference to the thread tops  7  and/or thread roots  8  of the internal thread  6 , as particularly indicated in  FIG. 4 . The edges in the inside surface  2  caused by the notches further facilitate the cutting of the internal thread  6  into the screw cap. As already stated, the notches  18  may be omitted, though. 
         [0021]      FIG. 2  shows a top view of the annular contact element  1  from the direction of the longitudinal central axis  17 . Here, the notches  18  are shown particularly well. In the exemplary embodiment shown they are arranged in a regular hexagon. However, this is not mandatory, of course. In the exemplary embodiment shown, the width  22  is 25.82 mm.  FIG. 3  shows the detail A from  FIG. 2 . The opening angle  23  of the notch  18  shown in detail, is similar to the other notches  18  shown in  FIG. 2 , and is 120°. Of course, this is only exemplary. 
         [0022]      FIG. 4  shows a longitudinal cross-section through the contact element  1  of the first exemplary embodiment. This longitudinal cross-section extends on the one side along and/or parallel to the longitudinal central axis  17  of the contact element  1 , on the other side this longitudinal cross-section extends in the exemplary embodiment shown also parallel and/or along a direction  13 , which extends normally to a plane  14  stretched between the edges  4  and  4 ′ of the contact element  1 . 
         [0023]    In  FIG. 4  it is shown particularly well how the diameter  5  of the receiving cavity  3 , starting at the edge  4 , tapers in the direction  11  towards the other edge  4 ′ within a first section. This first section ends at the minimal diameter  12 , which in the exemplary embodiment shown here, seen along the longitudinal central axis  17 , is located in the center between the edges  4  and  4 ′. Coming from the other side, i.e. starting at the edge  4 ′, the diameter  5  of the receiving cavity  3  tapers equally, but in the opposite direction, namely towards the other edge  4 . This section, beginning at the edge  4 ′, also ends at the centrally arranged minimal diameter  12 . In the exemplary embodiment shown the minimal diameter  12  is 28.5 mm, the diameter  5  in the area of the edges is 30.3 mm. The contact element  1  of this exemplary embodiment further comprises an exterior diameter  24  of 33 mm. The overall width  27  of the exemplary embodiment is 20 mm, measured parallel in reference to the longitudinal central axis  18  and/or the normal  13 . Half of the maximum difference of the diameter  26  amounts to 0.6 mm. The width  28  of the notches  18 , again in the direction parallel in reference to the longitudinal central axis  17  and/or the normal  13 , amounts to 13.33 mm. Shown particularly in  FIG. 6 , the angle  16  between a straight line  15  through the thread tops  7  of the internal thread  6  and the longitudinal central axis  17  and/or the normal  13  is 14° in the illustrated exemplary embodiment 5. Tests have shown that this angle  16  should range at least from 1° to 10°, preferably from 3° to 7°. The internal thread  6  arranged and/or formed at the inside surfaces  2  is not discernible in the illustration according to  FIG. 4 . Here, reference is made to the detail B, as shown enlarged in  FIG. 6 .  FIG. 6  shows the internal thread  6  of the exemplary embodiment shown, arranged at the inside surface  2  encircling the longitudinal central axis  17 , at a scale of 50:1. This illustrates that it represents a thread with a very low pitch  9  and also very low thread depth  10 . In the exemplary embodiment shown the pitch  9  and/or the height of the thread only amounts to 0.24 mm/rotation, with the pitch  9 , as generally known, being calculated from the distance of two adjacent thread tops  7 . The depth of the thread  10 , which states the difference in height in the direction towards a normal on the straight line  15  between the top of the thread  7  and an adjacent base of the thread  8 , amounts to only 0.2 mm in the exemplary embodiment shown. The pitch  9  and depth of the thread  10  may however be varied within the value range stated at the outset. Additionally, in  FIG. 6  it is shown particularly well that the thread tops  7  are embodied with an acute angle in the cross-section shown, while the roots of the threads may also be embodied rounded. In any case, by the acutely angled thread tops  7  the cutting of the internal thread  6  into the screw cap to be removed from a bottle is facilitated. Of course, the thread roots  8  and the thread tops  7  may also have different forms. The cutting of the respective internal thread  6  into the inside surface  2  can be performed by cutting methods known from prior art. 
         [0024]    The exemplary embodiment of an annular contact element  1  according to  FIG. 4  is advantageous, as explained at the outset, in that the screw cap to be removed from the bottle can be inserted into the receiving cavity  3  from both the direction  11  as well as the direction  11 ′. The operator is therefore not required to pay attention to place the bottle opener correctly onto the screw cap. Although it is surely beneficial in the sense of a practical handling, such a symmetrical design of the annular contact element is not mandatory. Accordingly,  FIG. 5  shows an exemplary embodiment, otherwise embodied like in  FIG. 4 , in which the diameter of the receiving cavity  3  tapers exclusively from the edge  4  in the direction  11  towards the other edge  4 ′. This allows a flatter design of the contact element and thus the bottle opener, however it is disadvantageous here in that the screw cap to be removed must always be inserted from the direction  11  into the receiving cavity  3 . The overall width  27  of this exemplary embodiment amounts to only 1 cm. The width  28  of the notches  18  amounts to approx. 6.6 mm. The other dimensions are consistent with those of the exemplary embodiment according to  FIG. 4 , and here it is pointed out once more that this is only one of many potential examples, of course. 
         [0025]    For reasons of completeness, finally it is also pointed out that in the exemplary embodiments shown the thread tops  7  of the respective internal thread are each located on a frustum surface, as are the thread roots  8 . In the exemplary embodiments shown the rotational axis of these frustum surfaces coincides with the longitudinal central axis  17 . Deviating from this conical embodiment there are other potential embodiments, in which the thread tops  7  and/or the thread roots  8  are located on a rotationally symmetrical surface, which not mandatorily represents a frustum surface. 
       LEGEND OF THE REFERENCE CHARACTERS 
       [0000]    
       
           1  Contact element 
           2  Inside surface 
           3  Receiving cavity 
           4 ,  4 ′ Edge 
           5  Diameter 
           6  Internal thread 
           7  Thread Top 
           8  Thread Root 
           9  Pitch 
           10  Depth of the tread 
           11 ,  11 ′ Direction 
           12  Minimum diameter 
           13  Direction 
           14  Level 
           15  Straight line 
           16  Angle 
           17  Longitudinal central axis 
           18  Notch 
           19  Angle 
           20  Handle part 
           21  Recess 
           22  Width 
           23  Opening angle 
           24  Exterior diameter 
           25  Rounded exterior edge 
           26  Half of maximum diameter difference 
           27  Overall width 
           28  Width