Abstract:
A closure arrangement for a container has a container neck, having slanted grooves extending in a circumferential direction of the container neck. A removable cap has a clamping projection for each one of the slanted grooves, wherein the clamping projections slide in the slanted groove when the cap is removed from or fastened to the container neck. Each one of the grooves is delimited by two opposed slanted surfaces. The width of the slanted grooves measured in the circumferential direction matches the size of the clamping projections in the circumferential direction.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to a closure arrangement for a container having a neck provided over its circumference with two slanted surfaces that have correlated therewith two clamping projections of a removable closure cap which slide along the slanted surfaces for closing and opening the container. 
     In such known closure arrangements the closure cap is provided with two clamping projections which are embodied like brackets and which can be positioned in a certain orientation axially onto the container neck. Subsequent rotation of the closure cap results in the clamping projections being moved along to diametrically opposed slanted surfaces so that the closure cap not only performs a rotary movement but at the same time an axial movement. In this context, closure caps are known that have an insert projecting into the container neck. At the circumference of the cap insert a sealing ring is positioned which in the closed position of the closure cap sealingly rests at the inner wall of the container neck. The removal of the closure cap, in general, is carried out after extended closing periods so that the friction at the inner wall that might be caused by possible adhesion must be overcome by this sealing ring. It is possible that the closure cap is not easily accessible. For example, the aforementioned containers are used in the motor vehicle sector and are provided at locations that are difficult to access such as, for example, hydraulic oil containers. When the closure cap of such a container must be removed, it is very difficult to overcome this frictional force between the sealing ring and the inner wall of the container. For removal of the closure cap it is not only required to perform a rotary movement but also a subsequent axial movement in order to remove the closure cap from the container. It has been found that very high pulling forces are required for removing the closure cap. When the closure cap is difficult to access, it is generally also impossible to employ a tool for removal of the closure cap. 
     It is therefore an object of the present invention to embody the closure arrangement of the aforementioned kind such that the closure cap can be removed with minimal force application even at locations that are difficult to access. 
     SUMMARY OF THE INVENTION 
     This object is inventively solved in that each slanted surface has positioned opposite thereto at a spacing a further slanted surface, so that the slanted surfaces delimit a groove at the circumference of the container neck, and that in the circumferential direction of the container neck the width of the groove matches the width of the clamping projection of the closure cap. 
     The inventive closure arrangement is characterized in that at the circumference of the container neck two diagonally opposed grooves are provided which are delimited respectively by two slanted surfaces. The two grooves at the circumference of the container neck thus extend spirally. Since their width matches the corresponding dimension (size) of the clamping projection of the closure cap, the clamping projections rest, when closing the container, at the upper slanted surface and, when removing the closure cap, at the lower slated surface of the grooves. Accordingly, for closing the container as well as for opening the container an axial force is employed. The user of the inventive closure arrangement thus must only rotate the closure cap and it is no longer required to pull or push the closure cap. Due to the forced guiding of the closure cap, the rotary movement of the closure cap results at the same time in an axial movement. Thus, the closure cap can be removed even at locations that are difficult to access. 
    
    
     BRIEF DESCRIPTION OF THE DRAWING 
     The object and advantages of the present invention will appear more clearly from the following specification in conjunction with the accompanying drawing, in which: 
     FIG. 1 shows the inventive closure arrangement partly in a side view and partly in section with the closure cap being in the locked position; 
     FIG. 2 shows in a representation corresponding to FIG. 1 the inventive closure arrangement with the closure cap in a partially removed position; 
     FIG. 3 is a view in the direction of arrow III of FIG. 2 onto the container neck opening 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The present invention will now be described in detail with the aid of several specific embodiments utilizing FIGS. 1-3. 
     The closure arrangement serves to close a container  1  by a closure cap  2 . The container  1  receives liquid media, for example, hydraulic oil, with which, for example, devices in motor vehicles such as power steering devices are actuated. The container  1  has a neck  3  which, in comparison to the remaining container, has a smaller cross-section. An insert  22  on the closure cap  2  projects into the container neck  3 . The insert  22  has an annular groove  4  in which a sealing ring  5 , preferably an O-ring, is received. It is clamped within the annular groove  4  upon closing the closure cap  2  in a manner to be disclosed in the following. The free rim  6  of the container neck  3  is wider than the remaining part of the neck  3  so that it projects radially from the neck  3 . At diametrically opposed locations the projecting rim  6  is provided with a respective groove  7 ,  8  which extends over an angular circumferential area  9  and  10  of more than 90°, preferably more than 100°. In FIG. 2 only the groove  7  is visible. In FIG. 1 the two grooves  7 ,  8  are only represented by curved lines. The two grooves  7 ,  8  extend in their shown embodiment over an angular distance  9 ,  10  of respectively 105° (FIG.  3 ). As FIG. 2 shows for the groove  7 , the grooves open into the end face  11  of the rim  6 . Accordingly, at the end face of the projecting rim  6  two thread segments  12  and  13  (FIG. 3) are positioned diametrically opposed to one another into which the clamping projections  14  of the closure cap  2  can be placed. In FIG. 2 the two clamping projections  14  are shown in cross-section, whereby the closure position is indicated (arrow pointing to the left) and also the release or open position (arrow pointing to the right). 
     The two grooves  7 ,  8  are thread segments which advantageously are embodied as flat threads. From FIG. 2 it can be taken for the groove  7  that the two slanted surfaces  15  and  16  delimit the groove  7 . The slanted surfaces extend parallel to one another at a spacing from the end face  11  of the rim  6 . The slanted surface  16  extends to the planar bottom side  17  of the rim  6 . The other slanted surface  15  extends to approximately half the height of the rim  6  to a nose-shaped projection  18  which projects in the direction toward the bottom side  17  of the rim  6 . Adjacent to the projection  18  the cutout  19 , open toward the bottom side  17 , is positioned which in the circumferential direction is delimited by a radially extending end wall  20 . The cutout  19  is delimited by a wall  21  extending parallel to the end face  11  from the projection  18  to the end wall  20 . 
     The other groove  8  is embodied in an analogous manner. In FIG. 2, in which the container  1  with a closures cap  2  is represented in a position rotated by 90° relative to FIG. 1, the end wall  20 , the projection  18 , and the cutout  19  open toward the bottom side  17  are clearly illustrated. 
     The closure cap  2  projects with its insert  22  into the container neck  3 . The insert  22  is covered over a portion of its height at a distance by a cylindrical closure cap rim  23 . Within the area of the closure cap surrounded by the closure cap rim  23  the two diagonally opposed clamping projections  14  are provided. In FIG. 2, the clamping projections  14  are shown in two different positions. The respective lengths of the clamping projects  14  are such that a portion of their undersides  24  and a portion of their respective upper sides  25  rest upon the two slanted surfaces  15 ,  16  ,of the respective grooves  7 ,  8 . The width of the groove  7 ,  8  of the circumferential direction matches for a quadrangular cross-section of the clamping projections  14  the diagonal of the cross-section of the clamping projections. The closure cap  2  is placed onto the container neck  3  such that the clamping projections  14  are inserted into the two grooves  7 ,  8  through the thread segments  12 ,  13 . A precise positioning of the closure cap  2  is not necessary. The closure cap  2  is rotated such that the clamping projections  14  with their boftom edge glide along the two slanted surfaces  16  of each one of the grooves  7 ,  8  until they contact and glide with their upper edge along the slanted surfaces  15  and then reach the projections  18  at the end of the slanted surface  15 . In FIG. 2, a position is shown for the damping projection  14  in which it is positioned directly in front of the projection  18 . Upon further rotation of the closure cap  2  the clamping projections  14  will glide under the projections  18  and then are received in the cutout  19  until they come to rest at the end walls  20  of the cutouts  19 . The end walls  20  thus provide stops for the closure cap  2  so that it is received in a defined position on the container neck  3 . Since the grooves  7 ,  8  extend spirally, the closure cap  2  and thus also its insert  22  are axially moved during rotation until the closure cap  2  rests directly at the end face  11  of the container neck  3 . During rotation for closing and the resulting axial movement of the closure cap  2  the sealing ring  5  is moved along the inner wall of the container neck  3  and is elastically deformed so that it will seal the container  1  in the closed position of the closure cap  2  in a reliable manner. The clamping projections  14  have a width in the circumferential direction preferably such that they extend between the end walls  20  and the projections  18 . This prevents that the closure cap  2  can be accidentally released from its closed position. 
     The slanted surface  16  of the grooves  7 ,  8  ends at the bottom side of the rim  6  of the container neck  3  at a spacing before the projection  18  of the opposed slanted surface  15 . Accordingly, the clamping projections  14  can reach without difficulties the cutouts  19  via the projections  18 . 
     For removing the closure cap  2 , it is rotated in the opposite direction whereby the clamping projections  14  are moved across the projections  18  into the grooves  7 ,  8 . Upon further rotation in the reverse direction the clamping projections  14  with their bottom side  24  will come into contact with the slanted surfaces  16  of the grooves  7 ,  8 . Accordingly the closure cap  2 , upon rotation in the reverse direction, will be moved axially in the direction toward its release position so that the closure cap  2  can be removed. The grooves  7 ,  8  extend over an angular distance  9 ,  10  of more than 100°, in the shown embodiment of approximately 105°. Since adjacent of the grooves  7 ,  8  in the circumferential direction the cutouts  19  are positioned, the rotary return angle for the closure cap  2  is substantially greater, i.e., is almost 180°. Accordingly, the grooves  7 ,  8  may have a relatively flat slant of only approximately 9°. This has the advantage that for removal of the closure cap the frictional forces can be easily overcome. When rotating the closure cap  2  for removal, the closure cap is lifted automatically as soon as it reaches the spirally extending grooves  7 ,  8  so that for opening the container  1  the user must only rotate the closure cap  2 . Thus, the closure cap  2  can be opened easily and closed easily even when it is difficult to access it and the cap can be gripped by the user, respectively, a mounting tool only with two or three fingers. 
     In order to tension, respectively, release the sealing ring  5  during closing or opening of the container  1  in a simple manner, the inner wall of the container neck  3  is advantageously conical above the seat of the ceiling ring. The diameter of the inner wall of the container neck  3  thus increases in the direction toward the closure cap  2 . This conical embodiment of the inner wall of the container neck  3  further improves the effect that the closure cap  2  can be removed with minimal force from the container neck  3 . In comparison to conventional container closure arrangements, opening the inventive closure arrangement only requires a release force of approximately 10% of a release force required for conventional containers. Due to the spiral extension of the grooves  7 ,  8 , the axial removal forces for removing the closure cap  2  are no longer needed. Moreover, an optimal manipulation of the closure cap  2  for closing and opening the container is provided. 
     The closure cap  2  can be produced of a suitable material, preferably a plastic material. The container  1  itself can also be produced of a suitable material, for example, a plastic material. 
     The specification incorporates by reference the disclosure of german priority document 298 03 502.2 of Feb. 28, 1998. 
     The present invention is, of course, in no way restricted to the specific disclosure of the specification and drawing, but also encompasses any modifications within the scope of the appended claims.