The invention relates to a cantilever parasol.
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.
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.
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.
The object of the invention is to make the steps of adjusting a cantilever parasol of the type mentioned at the outset smooth-running.
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.
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.
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.
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.
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.
To take up relatively large loads, it may be advantageous to use double rollers having a rocker-type horizontal tie bar.
The arm may be in rectilinear form or indeed be arcuate.
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.
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.
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.
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:
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;
b shows an illustration of the rollers in the rolling position, by way of the example of an alternative embodiment;
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;
b shows an illustration of the rollers in the braking position, by way of the example of the alternative embodiment;
In
The arm mounting 8 has a housing 16 comprising two housing halves 16a, 16b 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 (
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.
In the preferred exemplary embodiment, the rollers 18 have—as illustrated in
An alternative, but in principle equally valid, embodiment of the rollers and the guide contours is illustrated in
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 42a, 42b 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 42a, 42b are arranged in the housing 16, which is arranged on a mast head 48, with the wedges 42, 42a 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.
In order to limit in general the angle of tilt of the arm mounting 8, the mast head 48 includes abutments 50a, 50b which delimit the path of pivoting of corresponding abutments 52a, 52b in the housing 16 of the arm mounting 8. For fixing the tilt position when the arm is extended (
For fixing the extended position of the arm 6, the wedges 42a, 42b each include wedge surfaces 62a, 62b which cooperate on the one hand with wedge surfaces 64a, 64b on the mast head 48, and on the other hand further wedge surfaces 66a, 66b which cooperate with wedge surfaces 76a, 76b 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.
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.
The rollers 18 are arranged in a housing 80 which is formed from two housing parts 80a, 80b 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
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
Number | Date | Country | Kind |
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882/07 | Jun 2007 | CH | national |
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.
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/CH2008/000246 | 6/3/2008 | WO | 00 | 10/1/2009 |