Abstract:
The invention originates with a mast on the upper end of which a locking and tiltable jib support is arranged. A jib is guided in the jib support such that said jib can be slid and fastened and carries a roof construction on the outer end thereof, wherein said roof construction can be extended like a canopy, fan, or frame. To make the extension and retraction of the jib easier, it is proposed that the jib support be designed with at least four guide and locking rollers, of which at least two engage in a left-handed track and two in a right-handed track of the jib.

Description:
[0001]    This application claims priority of PCT application PCT/CH2008/000246 having a priority date of Jun. 4, 2007, the disclosure of which is incorporated herein by reference. 
     
    
     TECHNICAL FIELD 
       [0002]    The invention relates to a cantilever parasol. 
       BACKGROUND OF THE INVENTION 
       [0003]    A cantilever parasol of the type mentioned at the outset is known from WO 98/08411 A1. Displacement—that is to say, extension and retraction—of an arm on an arm mounting which is arranged at the upper end of the mast presents problems, because as the length of extension of the arm on the arm mounting increases, the arm tilts and clamps, with the result that the arm can in practice only be further displaced by lifting it. These problems are reinforced by the parasol being attached to the arm by means of a ball-and-socket joint, which allows the parasol to be further adjusted and adapted. However, this increases the risk that the arm will tilt sideways during displacement. Similar problems also arise, moreover, when a telescopic mast of a cantilever parasol of this kind is adjusted in height. 
         [0004]    Various constructions of cantilever parasols are known, allowing adjustment as the sun moves across the sky. WO 2005/018369 A1 discloses a cantilever parasol in which the arm is connected to the mast by means of a height-adjustable slide. A supporting strut connects the upper mast end to the central region of the arm. The disadvantage here is that the supporting strut determines a guidance curve, so there are limitations to the way the arm can be adjusted in the horizontal direction, independently of a guide support. This type of construction is not height-adjustable, is weighty and is bulky to ship. 
         [0005]    Tests have shown that guiding the arm by means of rollers does not in itself solve the problem. If the rollers are arranged below and above the arm, the extension movement begins to stick as the length of extension increases. To enable complete extension to be performed smoothly, with this type of construction too it is necessary to lift the parasol part somewhat and to extend the arm forward of the parasol part or retract it again. Additional problems arise if the arm is in the form of an arc, since this construction is prone to sideways tilting and clamping. This is exacerbated by the fact that the arm is typically difficult to access from the parasol side, because of furniture that is set up in the shade of the parasol. 
       SUMMARY OF THE INVENTION 
       [0006]    The object of the invention is to make the steps of adjusting a cantilever parasol of the type mentioned at the outset smooth-running. 
         [0007]    The object of the invention is achieved by a cantilever parasol. Here, the measures of the invention have the effect that the arm of the parasol—once locking has been released—can be moved over its entire length smoothly and without sideways tilting, that is to say that the arm can be extended and retracted without additional supports. These measures are particularly suitable for a parasol according to WO 98/08411 A. In this case, the arm need not be rectilinear, but rather the advantages are also obtained in particular if the arm and its guide tracks are in the form of an arc. This arc need not be in the shape of a circle segment but may also correspond to a segment of another shape of conical section (ellipse segment, hyperbola segment or parabola segment) or a synthesized form of parts placed together and having a varying radius of curvature. 
         [0008]    A particularly advantageous embodiment, with rollers as the guide members, since in that case the rollers—when they are put under load transversely with respect to the axis of the roller—prevent the end faces of the rollers from abutting in braking manner against the base faces of the groove-like guide track with the possibility of damage thereto, since they are at an appropriate distance from the base face. 
         [0009]    If the shapes of the guide member and the guide track are matched appropriately, the guide member may take the form of a brake block. 
         [0010]    It is advantageous if the construction of the cantilever parasol is such that the center axis of the guide tracks coincides approximately with the center axis of the mast and/or the arm, but in any case deviates from the center axis thereof by no more than 15%, preferably no more than 10%, of the thickness of the corresponding profile of the mast and/or the arm. 
         [0011]    The inventive solution is particularly advantageous with the construction of the cantilever parasol in accordance with which the arm mounting is constructed to have at least four rollers, of which respectively two engage in a left-hand guide track of the arm and two in a right-hand one. It is advantageous for stability and load distribution if the spacing between the axes of the front and rear rollers is 7 to 15%, preferably approximately 10%, of the length of extension of the arm. 
         [0012]    To take up relatively large loads, it may be advantageous to use double rollers having a rocker-type horizontal tie bar. 
         [0013]    The arm may be in rectilinear form or indeed be arcuate. 
         [0014]    It is an advantageous construction for the arm mounting to be arranged such that it can tilt on the mast and to have at least one locking device for fixing and releasing the extension position of the arm and its tilt position, individually or in combination. 
         [0015]    It is advantageous to use at least one wedge which is constructed and arranged such that, simultaneously, it provides a safety latching to the mast head by way of a toothed element, on the one hand, and a force-fitting connection between the mast head and the arm by way of wedge surfaces, on the other. Preferably, the locking device has two opposed wedges which may be clamped to one another. The toothed element of the wedge may have notches or grooves which, during the locking procedure, engage in corresponding grooves or notches on the mast head and provide a form-fitting locking. For fixing the arm force-fittingly, the wedge has surfaces which cooperate with wedge surfaces of a brake block, the latter abutting with frictional fit against the arm. 
         [0016]    The elements which have been mentioned above, which are claimed and which are described in the exemplary embodiments below and are to be used in accordance with the invention are not subject to any particular exceptional conditions as regards their size, shape, material used or technical design, with the result that the selection criteria that are known in the respective field of application can be used without restriction. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]    Further details, advantages and features of the subject matter of the present invention will become apparent from the description which follows of the accompanying drawings, in which—by way of example—cantilever parasols according to the invention are explained. In the drawings: 
           [0018]      FIG. 1  shows an illustration of a cantilever parasol according to a preferred exemplary embodiment of the invention, in the opened condition, in side view 
           [0019]      FIG. 2  shows an illustration of the cantilever parasol according to  FIG. 1 , in the folded condition; 
           [0020]      FIG. 3  shows the arm mounting of the cantilever parasol according to  FIG. 1 , in the section from  FIG. 1  and on a larger scale; 
           [0021]      FIG. 4  shows an exploded view of the arm mounting according to  FIG. 3 ; 
           [0022]      FIG. 5   a  shows an illustration of the rollers in the rolling position, by way of the example of a preferred embodiment of the arm profile or mast profile; 
           [0023]      FIG. 5   b  shows an illustration of the rollers in the rolling position, by way of the example of an alternative embodiment; 
           [0024]      FIG. 6   a  shows an illustration of the rollers in the braking position, by way of the example of the preferred embodiment of the arm profile or mast profile; 
           [0025]      FIG. 6   b  shows an illustration of the rollers in the braking position, by way of the example of the alternative embodiment; 
           [0026]      FIG. 7  shows an illustration of an embodiment—which is inventive but not claimed—in exploded view, of the connection region of a mast upper part which can be telescoped with a mast lower part, according to  FIG. 1 ; 
           [0027]      FIG. 8  shows a horizontal section through the height locking in  FIG. 7 . 
           [0028]      FIG. 9  shows the illustration of an alternative to the embodiment of the invention having two rollers which are inserted, by way of a horizontal tie bar to distribute the loads, in the direction of viewing the roller axis and the support pin; and 
           [0029]      FIG. 10  shows the illustration in cross-section transversely with respect to the roller axes according to  FIG. 9 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0030]    In  FIG. 1 , a cantilever parasol according to a preferred exemplary embodiment of the invention is shown from the side, opened, and designated  2  as a whole. The cantilever parasol substantially comprises a mast  4  and an arm  6  which is arranged such that it is retractable into the mast  4  and extendable therefrom—that is to say such that it is displaceable in the arm mounting  8  in its longitudinal direction—and a canopy structure  10  of conventional construction. The canopy structure is in this case opened in the manner of an umbrella, fan or tenter frame or in similar manner. In  FIG. 1 , the mast upper part  70  is in the extended position.  FIG. 2  shows the parasol from  FIG. 1  with the canopy structure  10  closed and the arm  6  retracted into the arm mounting  8  until an abutment  12  of the arm abuts against the arm mounting  8 . The arm mounting  8  is moreover tilted into the closed position about the tilt axis  14  in such a way that the arm  6  is pivoted against the mast  4 . In  FIG. 2 , the mast upper part is in the lowered position. 
         [0031]    The arm mounting  8  has a housing  16  comprising two housing halves  16   a ,  16   b  in which two rollers  18  are respectively arranged, which engage in a left-hand and a right-hand guide track  20  of the arm  6  ( FIG. 3 ). The guide tracks  20  take the form of a groove and have base faces  22  and side faces  24  with which the rolling surfaces  26  of the rollers  18  cooperate. The arm  6  and the guide tracks  20  may be in rectilinear form or, as in the present example, curved. 
         [0032]    The center axis  28  of the guide tracks  20  should not deviate from the center axis  30  of the arm  6  by more than 15%, preferably not more than 10%, of the thickness of the arm  6 . The lateral arrangement of the rollers  18  at the level of the center axis  30  of the arm  6  gives the desired smoothness of running. Depending on the length of the extension, considerable pressure on the rollers  18  is generated. To avoid overloading the rollers  18  and rolling surfaces, sufficient spacing between the rollers is established in the direction of rolling. A spacing between the rollers of 7 to 15%, preferably approximately 10%, of the length of extension of the arm  6  has proved suitable. 
         [0033]    In the preferred exemplary embodiment, the rollers  18  have—as illustrated in  FIGS. 5   a  and  6   a —lateral guide contours  32  which in each case delimit the rolling surfaces  26  of the rollers  18 . By means of the guide contours  32 , the rollers  18  cooperate with edge contours  34  on the guide tracks  20 . The dimensions of the rollers  18  and the guide tracks  20  are made such that, depending on the direction of force, the rollers  18  can either only act as rolling and guide rollers, as shown in  FIG. 5   a , or can also act as braking and locking means, as illustrated in  FIG. 6   a . The rollers  18  operate purely as rolling and guide rollers as in  FIG. 5   a  when they are put under load predominantly in a direction transverse with respect to their axis  37 . In that case, the guide contours  32  which cooperate with the edge contours  34  of the guide tracks  20  prevent the rollers  18  from penetrating further into the groove-like guide tracks  20 . This also prevents end faces  38  of the rollers  18  from being able to come into contact with the base faces  22  of the guide tracks  20 , exert a braking action and damage them. If, however, the rollers  18  are put under load in their axial direction, the rollers  18  migrate along their guide contours  32 , beyond the edge contours  34  of the guide tracks  20 , and are thus lifted away from the side faces  24  of the guide tracks  20  by means of their rolling surfaces  26 , and can be pressed further against the base faces  22  of the guide tracks by means of their end faces  38  and hence bring about a braking or blocking frictional fit, as is clear from  FIG. 6   a.    
         [0034]    An alternative, but in principle equally valid, embodiment of the rollers and the guide contours is illustrated in  FIGS. 5   b  and  6   b.    
         [0035]    The arm mounting  8  has a locking device  40  which has a double function, that is on the one hand to fix and release the tilt position of the arm mounting  8  about the tilt axis  14  in relation to the mast  4 , and on the other hand to secure the extended position of the arm  6 . For this purpose, the arm mounting  8  includes two wedges  42   a ,  42   b  which are constructed as mirror images of one another, and may be clamped and released in relation to one another by means of a threaded pin  44  and a screw-on handle  46 . The wedges  42   a ,  42   b  are arranged in the housing  16 , which is arranged on a mast head  48 , with the wedges  42 ,  42   a  cooperating as indicated below to lock the tilt position between the mast head  48  and the housing  16  and to secure the position of the arm  6  between the mast head  48  and the arm  6 . 
         [0036]    In order to limit in general the angle of tilt of the arm mounting  8 , the mast head  48  includes abutments  50   a ,  50   b  which delimit the path of pivoting of corresponding abutments  52   a ,  52   b  in the housing  16  of the arm mounting  8 . For fixing the tilt position when the arm is extended ( FIG. 1 ) and when the arm is retracted ( FIG. 2 ), there is provided a toothed element  54  in which, in the clamped condition, for each wedge  42   a ,  42   b , a notch  56  in the wedge  42   a ,  42   b  engages in a groove  58   a  or  58   b  in the mast head  48 . To enable the tilt positions to be altered, the handle  46  must be screwed open far enough for the notches  56  to be able to be released from the grooves  58   a  or  58   b  and to move beyond the intermediate web  60  on the mast head  48 , so that they can engage in the adjacent groove for the other tilt position. Screwing the handle closed re-establishes fixing. 
         [0037]    For fixing the extended position of the arm  6 , the wedges  42   a ,  42   b  each include wedge surfaces  62   a ,  62   b  which cooperate on the one hand with wedge surfaces  64   a ,  64   b  on the mast head  48 , and on the other hand further wedge surfaces  66   a ,  66   b  which cooperate with wedge surfaces  76   a ,  76   b  on a brake block  68  which abuts against the arm  6 . When the handle  46  is screwed closed, the brake block  68  is pressed against the arm  6  and holds it fixed in the selected position by force fit—that is to say frictional fit. Screwing it open releases the frictional fit and allows the arm  6  to be displaced. Because the frictional fit requires a smaller release of the handle  46  than releasing the toothed element  54  for the tilt position, releasing the locking of the arm  6  does not automatically mean that the tilt position is released. 
         [0038]    In the present exemplary embodiment, the mast  4  is made in two parts, with a mast upper part  70  being arranged telescopically inside a mast lower part  72  and being fixable in desired height positions by means of a fixing device  74 . Here, the mast upper part  70  has on two sides guide tracks  20  in which rollers  18  engage. The profile of the mast upper part  70  is identical to that of the arm  6 . 
         [0039]    The rollers  18  are arranged in a housing  80  which is formed from two housing parts  80   a ,  80   b  connected to the mast lower part  72 . The fixing device  74  is formed by a roller  18  which is mounted on a threaded pin  81  having a thread  84  and a press-fit flange  86 . By means of a handle  82  which is connected to the threaded pin, the roller  18  may be pressed force-fittingly by means of the press-fit flange  86  into the guide track  20  in the axial direction, as illustrated in  FIG. 6   a  or  FIG. 6   b , such that the end face  38  of the roller  18  acts on the base face  22  of the guide track  20  in braking or blocking manner. 
         [0040]      FIGS. 9 and 10  illustrate an alternative embodiment of the guide members in which the latter do not take the form of individual rollers but pairs  18  of rollers whereof the axes  37  are connected to a horizontal tie bar  35 . The horizontal tie bar  35  is inserted into the housing with a support pin  36 . This embodiment—which is somewhat more complicated—has the advantage that the loads can be distributed better. 
         [0041]    If the invention is to be used on the mast of a cantilever parasol, the mast  4  will be made in at least two parts, with a mast upper part  70  and a mast lower part  72 , and will be fixable in different height positions, with the mast upper part  70  having the guide tracks, and the guide members—preferably the rollers  18 —being connected to the mast lower part  72 . The mast profile of the mast upper part  70  may be identical to that of the arm  6 —as described above. Optionally, it is provided for at least one of the rollers  18  to be constructed with its end face  38  as the clamping face for a force-fitting height locking, and at least one of the axes of the rollers  18  to be constructed as a clamping screw  81  with a press-fit flange  86 . For this, the reader is referred in particular to  FIGS. 7 and 8 . 
         [0000]    
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 List of reference numerals 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                  2 
                 Cantilever parasol 
               
               
                   
                  4 
                 Mast 
               
               
                   
                  6 
                 Arm 
               
               
                   
                  8 
                 Arm mounting 
               
               
                   
                 10 
                 Canopy structure 
               
               
                   
                 12 
                 Abutment 
               
               
                   
                 14 
                 Tilt axis 
               
               
                   
                 16 
                 Housing 
               
               
                   
                 16a 
                 Housing halves 
               
               
                   
                 16b 
                 Housing halves 
               
               
                   
                 18 
                 Roller 
               
               
                   
                 20 
                 Guide track 
               
               
                   
                 22 
                 Base face 
               
               
                   
                 24 
                 Side faces 
               
               
                   
                 26 
                 Rolling surface 
               
               
                   
                 28 
                 Center axis of 20 
               
               
                   
                 30 
                 Center axis of 6 
               
               
                   
                 32 
                 Guide contour of rollers 
               
               
                   
                 34 
                 Edge contours of guide tracks 
               
               
                   
                 35 
                 Horizontal tie bar 
               
               
                   
                 36 
                 Support pin 
               
               
                   
                 37 
                 Axis of 18 
               
               
                   
                 38 
                 End face of rollers 
               
               
                   
                 40 
                 Locking device 
               
               
                   
                 42a 
                 Wedges 
               
               
                   
                 42b 
                 Wedges 
               
               
                   
                 44 
                 Threaded pin 
               
               
                   
                 46 
                 Handle for 40 
               
               
                   
                 48 
                 Mast head 
               
               
                   
                 50a 
                 Abutment of 48 
               
               
                   
                 50b 
                 Abutment of 48 
               
               
                   
                 52a 
                 Abutment of 16 
               
               
                   
                 52b 
                 Abutment of 16 
               
               
                   
                 54 
                 Toothed element 
               
               
                   
                 56 
                 Notch 
               
               
                   
                 58a, b 
                 Groove 
               
               
                   
                 60 
                 Intermediate web 
               
               
                   
                 62a 
                 Wedge surface of 42a 
               
               
                   
                 62b 
                 Wedge surface of 42b 
               
               
                   
                 64a 
                 Wedge surface of 48 
               
               
                   
                 64b 
                 Wedge surface of 48 
               
               
                   
                 66a 
                 Wedge surface of 42a 
               
               
                   
                 66b 
                 Wedge surface of 42a 
               
               
                   
                 67a 
                 Wedge surface of 68 
               
               
                   
                 67b 
                 Wedge surface of 68 
               
               
                   
                 68 
                 Brake block 
               
               
                   
                 68 
                 Mast upper part 
               
               
                   
                 72 
                 Mast lower part 
               
               
                   
                 74 
                 Fixing device 
               
               
                   
                 80 
                 Housing 
               
               
                   
                 80a 
                 Housing part 
               
               
                   
                 80b 
                 Housing part 
               
               
                   
                 81 
                 Threaded pin 
               
               
                   
                 82 
                 Handle for 74 
               
               
                   
                 84 
                 Thread 
               
               
                   
                 86 
                 Press-fit flange