Patent Publication Number: US-2020291666-A1

Title: Frame element with a support head, and building scaffold comprising such a frame element

Description:
The invention relates to a frame element for a building scaffold, the frame element having the following:
         a) A support head having a threaded spindle;   b) a frame pipe that can be mounted vertically in the building scaffold having a spindle receiving portion on a first axial frame pipe end, the threaded spindle being introduced partially into the spindle receiving portion;   c) a spindle nut mounted to the threaded spindle, the support head introducing its vertical load into the frame pipe via the threaded spindle in the mounted state of the frame element.       

     The previously described support head of the frame element generally serves to transfer a vertical load to a building scaffold. For example, a concrete formwork can be placed or mounted onto the support head. Furthermore, the support head can be used as temporary support during refurbishing. 
     The object of the present invention is to provide a frame element that can transfer significantly more vertical load via the support head without being significantly bulkier and heavier. The object of the present invention is also to provide a building scaffold having such a frame element. 
     The object according to the invention is achieved by a frame element having the features of claim  1  and a building scaffold according to claim  12 . The dependent claims specify useful further developments. 
     The object according to the invention is thus solved by a frame element for a building scaffold. The frame element has a support head having a threaded spindle. The frame element also has a frame pipe having a spindle receiving portion. The threaded spindle is partially introduced into the spindle receiving portion. The spindle receiving portion is on a first axial end of the frame pipe. A spindle nut is mounted to the threaded spindle in such a way that the support head introduces its load into the frame pipe via the threaded spindle in the mounted vertical state of the frame element. The spindle receiving portion has a first spindle positioning nut that reduces the inner diameter of the frame pipe. 
     The first spindle positioning groove significantly improves the vertical load bearing capacity of the frame element without considerably increasing the weight of the frame element. The first spindle positioning groove increases the load bearing capacity of the frame element in two respects: On the one hand, the solidity of the frame pipe is increased in the region of the first spindle positioning groove due to the configuration of the first spindle positioning groove. On the other hand, the threaded spindle is oriented better in the frame pipe thanks to the reduced diameter of the frame pipe on the first spindle positioning groove. Overall, this results in the significantly improved suitability of the frame element for vertical load transfer. 
     The threaded spindle is preferably oriented as centered as possible in the frame pipe by the spindle positioning groove, a clearance fit being present between the threaded spindle and frame pipe for introducing the threaded spindle into the frame pipe. The longitudinal axis of the threaded spindle has the angle ß relative to the longitudinal axis of the frame pipe, the angle ß being less than 1°, in particular less than 0.8°, preferably less than 0.7°. As a result, the vertical load is guided into the frame pipe as centrally as possible to keep the moments occurring in the building scaffold to a minimum. 
     The first spindle positioning groove can extend parallel to the longitudinal axis of the frame pipe. At least three grooves distributed across the circumference of the frame pipe are preferably provided for orienting the threaded spindle. In a preferred embodiment of the first spindle positioning groove, however, it extends in the circumferential direction of the frame pipe. The first spindle positioning groove can be designed to be discontinuous or circumferential in the circumferential direction of the frame pipe. 
     Particularly effective centering of the threaded spindle in the frame pipe is done when the axial spacing of the first spindle positioning groove from the first axial frame pipe end is smaller than the inner diameter of the spindle receiving portion. 
     More preferably, the spindle receiving portion preferably has a second spindle positioning groove. The second spindle positioning groove is axially spaced apart from the first spindle positioning groove and reduces the inner diameter of the frame pipe. Due to the second spindle positioning groove, the orientation of the threaded spindle in the frame pipe is defined by at least two spindle positioning grooves that are spaced axially apart from each other, as a result of which the orientation, in particular the centering, of the threaded spindle is particularly precise. 
     The second spindle positioning groove can extend parallel to the longitudinal axis of the frame pipe. At least three grooves distributed across the circumference of the frame pipe are preferably provided for orienting the threaded spindle. As an alternative to this, the second spindle positioning groove can extend in the circumferential direction of the frame pipe. The second spindle positioning groove can be designed to be discontinuous or circumferential in the circumferential direction of the frame pipe. 
     In a more preferred embodiment of the invention, the spindle receiving portion has a third spindle positioning groove. The third spindle positioning groove is spaced axially further away from the first spindle positioning groove than the second spindle positioning groove. The third spindle positioning nut reduces the inner diameter of the frame pipe. The third spindle positioning groove improves the orientation, in particular the centering, of the threaded spindle in the frame pipe. 
     The third spindle positioning groove can extend parallel to the longitudinal axis of the frame pipe. At least three grooves distributed across the circumference of the frame pipe are preferably provided for orienting the threaded spindle. As an alternative to this, the third spindle positioning groove can extend in the circumferential direction of the frame pipe. The third spindle positioning nut groove can be designed to be discontinuous or circumferential in the circumferential direction of the frame pipe. 
     The third spindle positioning groove is preferably spaced less axially far apart from the second spindle positioning groove than the second spindle positioning groove is from the first spindle positioning groove. 
     Particularly preferably, the second spindle positioning groove and/or the third spindle positioning groove reduces the inner diameter of the frame pipe just as much as the first spindle positioning groove. The radial play of the threaded spindle in the frame pipe is reduced significantly as a result of this, it nevertheless remaining easy to introduce the threaded spindle into the frame pipe. 
     On its second axial frame pipe end, which is opposite the first axial frame pipe end, the frame pipe can have a pin receiving portion into which a pin of a further frame element can be introduced. The pin receiving portion can have a first pin positioning groove that reduces the inner diameter of the frame pipe. The first pin positioning groove mechanically reinforces the frame pipe in the region of the pin receiving portion. 
     The first pin positioning groove can extend parallel to the longitudinal axis of the frame pipe. At least three grooves distributed across the circumference of the frame pipe are preferably provided for orienting the threaded spindle. As an alternative to this, the first pin positioning groove can extend in the circumferential direction of the frame pipe. The first pin positioning groove can be designed to be discontinuous or circumferential in the circumferential direction of the frame pipe. 
     The axial spacing of the first pin positioning groove from the second axial frame pipe end is preferably smaller than the inner diameter of the first pin positioning groove. 
     More preferably, the pin receiving portion has a second pin positioning groove that is axially spaced apart from the first pin positioning groove and reduces the inner diameter of the frame pipe. As a result, the pin of a further frame element is centered at two pin positioning grooves in the pin receiving portion that are spaced axially apart from each other. 
     The second pin positioning groove can extend parallel to the longitudinal axis of the frame pipe. At least three grooves distributed across the circumference of the frame pipe are preferably provided for orienting the threaded spindle. As an alternative to this, the second pin positioning groove can extend in the circumferential direction of the frame pipe. The second pin positioning nut groove can be designed to be discontinuous or circumferential in the circumferential direction of the frame pipe. 
     In a more preferred embodiment of the frame element, the frame pipe has a node point on which
         a) a crossbar of the frame element is connected to the frame pipe, or   b) a coupling point is installed for connecting a crossbar,
 
the frame pipe having a first reinforcing groove in the region of the node point. The first reinforcing groove is spaced less than 15 cm from the node point in a first axial direction and reduces the inner diameter of the frame pipe or increases the outer diameter of the frame pipe. Due to the first reinforcing groove, the frame element is reinforced in an area in which it is loaded particularly heavily, namely in the region of the node point. Due to the first reinforcing groove, the frame pipe offers a higher resistance and moment of inertia in the region of the pressure point of the crossbar. The coupling point can be designed in the form of a rosette for connecting a crossbar.
       

     More preferably, the frame pipe has a further reinforcing groove in the region of the node point that is spaced less than 15 cm from the node point in a second axial direction and reduces the inner diameter of the frame pipe or increases the outer diameter of the frame pipe. The second axial direction is opposite the first axial direction. In other words, the node point is reinforced by a further reinforcing groove in both axial directions by one reinforcing groove in each case. 
     The spindle positioning groove(s) and the reinforcing groove(s) preferably reduces the inner diameter of the frame pipe to the same extent. 
     The object according to the invention is also solved by a building scaffold having a previously described frame element. 
     Further features and advantages of the invention are presented in the following detailed description of multiple exemplary embodiments of the invention, in the claims and based on the figures of the drawing that shows details that are essential to the invention. 
     The features shown in the drawing are depicted in such a way that the special features according to the invention can be made clearly visible. The various features can each be realized in variants of the invention individually or in groups in any combination. 
    
    
     
       Shown are: 
         FIG. 1  a sectional view of a frame element from the prior art; 
         FIG. 2  a sectional view of a frame element according to the invention; 
         FIG. 3  a top view of a node point of a frame element according to the invention; and 
         FIG. 4  a perspective view of a building scaffold according to the invention. 
     
    
    
       FIG. 1  shows a frame element  10  according to the prior art. Frame element  10  has a frame pipe  12 . A spindle receiving portion  14  is designed in frame pipe  12 . A threaded spindle  16  is introduced into spindle receiving portion  14 . Threaded spindle  16  has an external thread  18 . Known frame element  10  also has a spindle nut  20 . Spindle nut  20  has an internal thread  22  with which spindle nut  20  is attached to external thread  18  of threaded spindle  16 . 
     Spindle receiving portion  14  has the same inner diameter along the entire axial direction. Threaded spindle  16 , which is supported axially via spindle nut  20  on frame pipe  12 , has a position skewed at angle ß. More specifically, longitudinal axis  23   a  of threaded spindle  16  is inclined by angle ß relative to longitudinal axis  23   b  of frame pipe  12 . The angle ß is typically 1.29°. 
     In contrast to  FIG. 1 ,  FIG. 2  shows a frame element  10  according to the invention. According to  FIG. 2 , frame element  10  has a frame pipe  12  with a spindle receiving portion  14 . Furthermore, frame element  10  has a threaded spindle  16  on which a spindle nut  20  is arranged. Spindle receiving portion  14  has a first spindle positioning groove  24 , a second spindle positioning groove  26  and a third spindle positioning groove  28 . Spindle positioning grooves  24 ,  26 ,  28  define the effective inner diameter of spindle receiving portion  14  for threaded spindle  16 . Due to spindle positioning grooves  24 ,  26 ,  28 , threaded spindle  16  is arranged in frame pipe  12  at a much smaller inclination. The angle ß between longitudinal axis  23   a  of threaded spindle  16  and longitudinal axis  23   b  of frame pipe  12  is, in particular, less than 0.8°, preferably less than 0.7°. In comparison to frame element  10  according to  FIG. 1 , the vertical load bearing capacity of frame element  10  is increased by approximately 10% as a result. In addition thereto, the spindle receiving portion is mechanically reinforced against kinking by spindle positioning grooves  24 ,  26 ,  28 . 
       FIG. 2  depicts a further frame element  30  (dashed lines) whose pin  32  can be introduced into frame pipe  12 . 
     Frame pipe  12  thus has a first axial frame pipe end  34  into which threaded spindle  16  can be introduced. Furthermore, frame pipe  12  has a second axial frame pipe end  36  into which pin  32  of further frame element  30  can be introduced. A pin receiving portion  38  for receiving pin  32  in frame pipe  12  is designed on second axial frame pipe end  36 . A mechanical reinforcement of pin receiving portion  38  as well as improved centering of pin  32  is done by a first pin positioning groove  40  and a second pin positioning groove  42 . 
       FIG. 3  shows a further frame element according to the invention  10 . Frame element  10  has a node point  44  having a coupling point  46 . In the present case, coupling point  46  is designed in the form of a rosette. Crossbars  48 ,  50  are arranged at coupling point  46 . 
     It is evident from  FIG. 3  that frame pipe  12  has a first reinforcing groove  54  which is designed to be spaced apart from coupling point  46  in frame pipe  12  in a first axial direction  56 . A second reinforcing groove  58  is designed in frame pipe  12  in first axial direction  56  at a distance from coupling point  46 . Shoulders  60 ,  62  of crossbars  48 ,  50  are in the region of frame pipe  12  between first reinforcing groove  54  and second reinforcing groove  58  on frame pipe  12 . First reinforcing groove  54  and second reinforcing groove  58  thus form an area of frame pipe  12  that is mechanically especially stable in which, in particular, the mechanical stability against buckling of frame pipe  12  is very high. 
     Frame pipe  12  has a further reinforcing groove  64 . Further reinforcing groove  64  is spaced apart from coupling point  46  in a second axial direction  66 . First axial direction  56  and second axial direction  66  run along longitudinal axis  23   b  of frame pipe  12 , second axial direction  66  being opposite first axial direction  56 . Further reinforcing groove  64  allows insertion tabs  68 ,  70  of crossbars  48 ,  50  to be pressed mechanically against frame pipe  12  particularly firmly without resulting in the plastic deformation of frame pipe  12  when crossbar  48  and/or  50  is loaded. 
     Alternatively or in addition to described reinforcing grooves  54 ,  58 ,  64 , frame element  10  can be designed with at least one additional reinforcing groove  72  in frame pipe  12  between axially adjacent coupling points, of which only one coupling point  46  is depicted in  FIG. 3 . 
       FIG. 4  shows a building scaffold  74  having multiple frame elements, of which only a first frame element  10  is provided with a reference character in  FIG. 4  for the sake of clarity. By way of example, frame element  10  has a node point  44  on which—likewise by way of example—a crossbar  48  is arranged. Because of the small depiction of building scaffold  74 , no groove according to the invention is visible in  FIG. 4 . For the removal of a load, frame element  10  has a support head  76 . 
     When viewing all figures of the drawing together, the invention relates, in summary, to a frame element  10  comprising a frame pipe  12  into which a threaded spindle  16  is partly introduced at one end. Threaded spindle  16  is guided in frame pipe  12  by at least one spindle positioning groove  24 ,  26 ,  28 , in particular multiple spindle positioning grooves  24 ,  26 ,  28 . Frame pipe  12  is mechanically reinforced by spindle positioning groove(s)  24 ,  26 ,  28  in the region of threaded spindle  16  received in frame pipe  12 . At the same time, the maximum inclination of threaded spindle  16  in frame pipe  12  is reduced by spindle positioning groove(s)  24 ,  26 ,  28 . Overall, a force can thus be substantially more strongly applied to frame element  10  in the direction of longitudinal axis  23   b  of frame pipe  12 . At the other end, frame pipe  12  can have at least one pin positioning groove  40 ,  42 , in particular multiple pin positioning grooves  40 ,  42 . Alternatively or in addition thereto, frame pipe  12  can have at least one reinforcing groove  54 ,  58 ,  64  in the region of a node point  44 . Alternatively or in addition thereto, frame pipe  12  can have at least one additional reinforcing groove  72  between two node points  44 .