The invention relates to an apparatus for fastening a mounting rail on a threaded shank, in particular that of a hanger bolt. Such apparatuses are often used for the substructure of solar modules on roofs.
DE 20 2006 008 867 U1 discloses an apparatus for fastening a solar installation on a roof. The apparatus comprises a hanger bolt, to the threaded shank of which a flat metal connecting plate is screwed firmly by means of two nuts. The metal connecting plate has a elongated hole, on which a mounting rail can be fastened in an adjustable manner. A second screw is necessary for fastening the mounting rail.
DE 20 2007 008 471 U1 discloses an apparatus which can fix a profile rail to another component by means of a wedge, which is guided on a ramp, and just one screw. The apparatus is designed for a planar mounting base which is larger than the two-part rear surface of the apparatus. Moreover, the distance between the screw and the profile rail is fixedly predetermined.
It is one object of the invention to provide an apparatus for fastening a mounting rail on a threaded shank, wherein the apparatus does not require any screws by its own and by means of which the mounting rail may be adjusted both axially and radially in relation to the threaded shank.
This object is achieved by the apparatus specified in claim 1. Accordingly, this apparatus is provided for fastening a mounting rail on a threaded shank, wherein the mounting rail comprises a contact side and a retaining edge. Such a retaining edge may especially be provided laterally. Preferably, however, the retaining edge is, at the same time, the edge of an undercut screw-connection channel in the contact side of the mounting rail. The threaded shank for the apparatus may be arranged at a fixed location and may be, in particular, that of a hanger bolt.
The apparatus comprises a retaining element, a clamping element and two nuts, wherein the retaining element has a supporting surface for the contact side of the mounting rail and also a gripping extension, which projects in relation to the supporting surface and is configured for engaging behind the retaining edge. It is possible for such a gripping extension to be configured cross-sectionally, in a known manner, like a hook and to have a joining slope. Furthermore, the threaded shank passes through the retaining element in a first elongated hole and through the clamping element in a second elongated hole, wherein the two elongated holes are directed transversely to the applied mounting rail. In addition, it is provided that the retaining element and the clamping element are arranged axially between the two nuts, which engage with the threaded shank, and can be braced together by means of these nuts at various positions along the threaded shank.
It is also an essential feature that an axial bracing together causes the clamping element and the mounting rail to advance toward one another radially. For this purpose, the retaining element comprises a plurality of successively arranged bracing slopes, which slope up uniformly with increasing distance from the mounting rail and onto which the clamping element can slide downward by means of corresponding mating slopes. With nuts braced in relation to one another, the mounting rail is then clamped against the gripping extension by the clamping element and is held down on the supporting surface by the gripping extension.
In a manner which allows for easy assembly, the threaded shank and the nuts can be used both for fastening the apparatus and, indirectly, for fixing the mounting rail in place. A screw dedicated for fastening the mounting rail is no longer necessary. By means of the two elongated holes, which are oriented in the same direction, it is possible for the retaining element together with the clamping element to be displaced radially as a single unit in relation to the threaded shank. The wedge and the ramp of the apparatus known from the prior art would be unsuitable for this purpose since, provided with corresponding elongated holes, they would be disadvantageously high. The fact that in each case a plurality of successively arranged bracing and mating slopes, which act as a sliding pairing, are provided according to the invention means that it is possible for both the retaining element and the clamping element, despite the radial adjustment range, to be configured in a flat, and thus material-saving, manner, in particular in the form of extrusions with punched elongated holes. Moreover, the apparatus can be braced together by the two nuts, as required, at any desired positions along the threaded shank.
The bracing slopes and the mating slopes can be straightforwardly configured in cross section like sawtooth profiles with an asymmetric flank pattern, wherein upwardly sloping and downwardly sloping flanks may be spaced apart from one another, in particular by slope-free portions. In a particularly advantageous embodiment, the clamping element has a second group of mating slopes, which are arranged symmetrically in relation to the first mating slopes, and therefore the clamping element can be mounted in a manner in which it is rotated alternately through 180° about the threaded shank. The first and second mating slopes can then be viewed, in cross section, as a symmetrical sawtooth profile or preferably, with slope-free portions, as a symmetrical trapezoidal profile. In order to achieve constant sliding and clamping conditions over the entire adjustment range of the elongated holes, it is expedient, irrespective of the profile shape selected, for the bracing and mating slopes to be arranged mostly around the region of the elongated holes.
In an advantageous further development, the apparatus comprises a resilient element, which biases the clamping element in a direction which slopes up in relation to the bracing slopes. This allows the apparatus to be kept open automatically for the purpose of placing the mounting rail in position.
The invention will be explained in more detail hereinbelow by way of two exemplary embodiments and with reference to the drawing, in which:
FIG. 1 shows an apparatus arranged on a hanger bolt and retaining a mounting rail,
FIGS. 2
a to 2d show the sequence for assembling the apparatus according to FIG. 1,
FIGS. 3
a and 3b show the transverse and longitudinal adjustability of the apparatus according to FIG. 1 in relation to the hanger bolt,
FIG. 4 shows a further apparatus arranged on a hanger bolt and retaining a mounting rail,
FIGS. 5
a and 5b show the final step for assembling the apparatus according to FIG. 4,
FIG. 6 shows the turned-over clamping element of the apparatus according to FIG. 4, and
FIG. 7 shows the retaining element of the apparatus according to FIG. 4.
The apparatus according to FIG. 1 comprises a retaining element 1, a clamping element 2 and two nuts 3 and 4. The apparatus is used to fasten a mounting rail 20, only part of which is illustrated here, on the threaded shank 30 of a conventional hanger bolt 31. The axis of the threaded shank 30 here crosses the mounting rail 20 outside the same, and in a right angle thereto. The hanger bolt 31 may have its cutting thread, which is provided at the bottom, arranged at a fixed position, for example on a wooden roof rafter.
As can also be seen particularly from FIG. 2a, the mounting rail 20, in a known manner, has a contact side 21 with an undercut screw-connection channel 24, which subdivides the contact side 21 into two halves of approximately equal width. That opening edge of the undercut screw-connection channel 24 which is closer to the threaded shank 30 is provided as a retaining edge 22 for the apparatus. Moreover, a part of the right-hand outer side of the mounting rail 20, this right-hand outer side being directed toward the threaded shank 30, is provided as a clamping portion 23 for the apparatus, wherein the clamping portion 23 and the contact side 21 are perpendicular to one another. A likewise undercut screw-connection channel can be seen on the upper side of the mounting rail 20, this upper side being located opposite to the contact side 21. This screw-connection channel can be used for mounting further components. Such components may be, for example, so-called module clamps for the further fastening of photovoltaic modules, as illustrated clearly, inter alia, in DE 20 2006 008 867 U1.
It can also be seen from FIG. 2a that the retaining element 1 has a supporting surface 7 for the contact side 21 of the mounting rail 20 and also a gripping extension 8, which projects in relation to the supporting surface 7 and is configured for engaging behind the retaining edge 22. The gripping extension 8 can be seen as a hook in cross section and acts in relation to the retaining edge 22 like a hook, which is open toward the threaded shank 30. The gripping extension also has a joining slope 15, beneath which the retaining edge 22 can be straightforwardly pushed like a form-closure connection, as can be seen in the final-assembly state according to FIG. 2d. The joining slope 15 and the retaining edge 22, moreover, are configured such that the mounting rail 20, even in the case of a sloping arrangement, is already retained with provisional clamping action on the gripping extension 8, which is particularly advantageous for mounting on a pitched roof. It can also be seen that the gripping extension 8 subdivides the supporting surface 7 into two portions, and these portions carry the contact side 21 of the mounting rail 20 in a statically advantageous manner on either side of the undercut screw-connection channel 24.
If the apparatus is put together according to FIG. 2b, the threaded shank 30 passes through the retaining element in a first elongated hole 5 and through the clamping element in a second elongated hole 6, wherein the two elongated holes 5 and 6 are directed transversely to the placed-in-position mounting rail 20, and the retaining element 1 and the clamping element 2 are arranged axially between the two nuts 3 and 4 which engage with the threaded shank 30. In the final-assembly state according to FIG. 2d, the retaining element 1 and the clamping element 2 are then braced together by means of the nuts 3 and 4 at one of a number of positions along the threaded shank 30. For this purpose, the rear sides of the retaining element 1 and of the clamping element 2 are planar and are both perpendicular to the axis of the threaded shank 30, and therefore the nuts 3 and 4 can come suitably into abutment there. Both the retaining element 1 and the clamping element 2 are configured as flat extrusions, wherein the elongated holes 5 and 6 are preferably provided by punching.
In order that axial bracing together results in the clamping element 2 and the mounting rail 20 advancing toward one another radially, the retaining element 1, as can be seen, once again, from FIG. 2a, has four successively arranged bracing slopes 9a to 9d, which slope up uniformly with increasing distance from the mounting rail 20 and on which the clamping element 2 can slide downward. For this purpose, the clamping element 2 has four corresponding mating slopes 10a to 10d, which form sliding pairings with the bracing slopes 9a to 9d, respectively, and therefore the clamping element 2 can be displaced smoothly in relation to the retaining element 1. According to the assembly step from FIG. 2c to FIG. 2d, an axial movement of the clamping element 2 towards the retaining element 1 here results in the clamping element 2 being moved radially towards the clamping portion 23 of the mounting rail 20. With nuts 3 and 4 braced in relation to one another according to FIG. 2d, the mounting rail 20, finally, is clamped against the gripping extension 8 by the one face side 16 of the clamping element 2 and, in addition, is held down on the supporting surface 7 by the gripping extension 8.
The bracing slopes 9a to 9d and the mating slopes 10a to 10d can be seen cross-sectionally according to FIG. 2a as corresponding sawtooth profiles with an asymmetric flank pattern, wherein upwardly sloping and downwardly sloping flanks are spaced apart by slope-free portions. The bracing slopes 9a and 9d are configured uniformly. They thus have a uniform upward slope α of, in this case, about 25° in relation to a plane which is perpendicular to the threaded shank 30. The rear or downwardly sloping flanks are arranged vertically to this plane. It can also be seen that the bracing slopes 9a to 9d begin and end on the same level and are spaced apart at equal intervals from one another. The mating slopes 10a to 10d on the clamping element 2 are configured correspondingly and/or form a matching mating shape.
In order that the clamping element 2, once placed in position on the threaded shank 30 according to FIG. 2b, does not, according to FIG. 2c, slide downward automatically along the bracing slopes 9a to 9d and block the mounting rail 20 from being placed in position as a result, the clamping element 2 can easily be held back manually during assembly. In a further development which is not illustrated specifically, it is possible for the apparatus to comprise a resilient element, which biases the clamping element 2 and retains the same compliantly in an upper portion on the bracing slopes 9a to 9d. It is only when the nut 4 is tightened that the clamping element 2 is then displaced downward, and/or toward the mounting rail 20, against to the resilient force of this resilient element.
As an alternative to the assembly step from FIG. 2a to FIG. 2c, it is also possible to place the mounting rail 20 in position on the retaining element 1 at first and to place the clamping element 2 and the nut 4 in position on the threaded shank 30 subsequently. The assembly sequence illustrated is, however, preferred, since it is possible here to arrange the apparatus beforehand on a non-fixed hanger bolt and to provide the fitter therefore with a pre-assembled assembly. A pre-assembly position similar to that according to FIG. 2b, and possibly achieved by the aforementioned resilient element, is particularly expedient here.
FIGS. 3
a and 3b show the radial and axial adjustability of the apparatus. The mounting rail 20 can be mounted at different distances from the threaded shank 30 by means of the apparatus according to FIG. 1. Thus, FIG. 3a shows a position at a small distance, and FIG. 3b shows a position at a larger distance, from the threaded shank 30. This is expedient particularly if a relatively long mounting rail is to be fastened on a plurality of threaded shanks which are not precisely in alignment. The extent of this radial adjustability is determined substantially by the length of the elongated holes 5 and 6. It is also advantageous in this context for the bracing slopes 9a to 9d and the mating slopes 10a to 10d to be arranged around the region of the elongated holes 5 and 6, and therefore the clamping element 2, during bracing, does not tilt in relation to the retaining element 1, and similar sliding and clamping conditions prevail along the elongated holes 5 and 6. In the final-assembly state, the elongated holes 5 and 6 are approximately congruent, wherein it is also conceivable for these elongated holes to be rendered congruent for a maximum adjustment range in the position according to FIG. 2b.
As can be seen, in addition, from FIGS. 3a and 3b, the apparatus according to FIG. 1 may also be arranged at various positions along the threaded shank 30. Thus, FIG. 3a shows a position at a small distance, and FIG. 3b shows a position at a relatively large distance from the free end 32 of the threaded shank 30. This is expedient particularly if a relatively long mounting rail is to be fastened on a plurality of threaded shanks which do not end precisely in the same plane, as may be the case, for example, if there is an uneven underlying surface or where hanger bolts are screwed in to different depths. The longer a threaded shank, the larger is also the axial adjustment range over which the retaining element 1 and the clamping element 2 can be braced in relation to one another by means of the nuts 3 and 4. In addition to the radial and axial adjustability, the apparatus according to FIG. 1, of course, can also be rotated about the axis of the threaded shank 30.
FIG. 4 shows a further apparatus according to the invention, which is comparable to the apparatus according to FIG. 1. As can be seen, in particular, from FIGS. 6 and 7, the retaining element 1′ has three bracing slopes 11a to 11c and the clamping element 2′ has three mating slopes 12a to 12c. The fundamental difference from the apparatus according to FIG. 1 is that the clamping element 2′ has a second group of three mating slopes 13a to 13c, which are arranged symmetrically in relation to the first mating slopes 12a to 12c. The first and the second mating slopes 12a to 12c and 13a to 13c can thus be seen cross-sectionally as a symmetrical trapezoidal profile. This means that the clamping element 2′ can also be mounted in a manner in which it is rotated through 180° about the threaded shank 30, which facilitates assembly on site, in particular on a roof. It can also clearly be seen from FIGS. 6 and 7 that, as with the apparatus according to FIG. 1, the bracing slopes and mating slopes are arranged around the region of the elongated holes 5 and 6, respectively. FIGS. 5a and 5b, finally, show, in a manner comparable to FIGS. 2c and 2d, the final assembly step for the apparatus according to FIG. 4, wherein, in this case, the mounting rail 20 has already had the retaining edge pushed manually beneath the gripping extension of the retaining element.