Turnbuckle for Tensioning Frame Formwork Elements

Abstract

The invention relates to a turnbuckle ( 1 ) for bracing frame formwork elements ( 2 ), comprising a first clamping device ( 7 ) which has a crossmember ( 9 ) and a first clamping jaw ( 10 ). The crossmember ( 9 ) has a toothed section ( 12 ) comprising a row of track teeth ( 13 ) which are arranged one behind the other and extend in parallel with one another. The turnbuckle ( 1 ) furthermore has a second clamping device ( 8 ) with a second clamping jaw ( 14 ) and a guide device ( 19 ). The second clamping device ( 8 ) can be moved in a bracing direction along the crossmember ( 9 ) towards the first clamping jaw ( 10 ). The turnbuckle ( 1 ) further has a wedge ( 20 ) which can be displaced in a guided manner by the guide device ( 19 ) along a wedge insertion direction and can be brought into engagement with at least one of the track teeth ( 13 ) in order to fix the two clamping devices ( 7, 8 ) in a bracing position with respect to one another. The guide device ( 19 ) has a cross brace ( 21 ) which can be displaced transversely to the wedge insertion direction between an unlocking position and a locking position. The crossmember ( 21 ) is designed and arranged in such a way that the cross brace ( 21 ) in the locking position limits a stroke of the wedge ( 20 ) in a direction orthogonal to the toothed section ( 12 ) in such a way that the wedge ( 20 ) in the clamping position can be brought into engagement with the at least one track tooth ( 13 ). The cross brace ( 21 ) enables a greater stroke of the wedge ( 20 ) in the unlocking position.

1 . A turnbuckle ( 1 ) for bracing frame formwork elements ( 2 ), comprising a first clamping device ( 7 ) having a crossmember ( 9 ) and a first clamping jaw ( 10 ), the crossmember ( 9 ) having a toothed portion ( 12 ) with a row of track teeth ( 13 ) arranged one behind the other and running in parallel with one another, and comprising a second clamping device ( 8 ) having a second clamping jaw ( 14 ) and a guide device ( 19 ), the second clamping device ( 8 ) being movable in a clamping direction along the crossmember ( 9 ) toward the first clamping jaw ( 10 ), and having a wedge ( 20 ) which, guided by the guide device ( 19 ), is movable along a wedge-driving direction and can be brought into engagement with at least one of the track teeth ( 13 ) in order to fix the two clamping devices ( 7 ,  8 ) with respect to one another in a bracing position,
 characterized in that   the guide device ( 19 ) has a cross brace ( 21 ) which can move transversely to the wedge-driving direction between an unlocking position and a locking position, the cross brace ( 21 ) being designed and arranged such that in the locking position, the cross brace ( 21 ) limits a stroke of the wedge ( 20 ) in a direction orthogonal to the toothed portion ( 12 ) such that in the bracing position, the wedge ( 20 ) can be brought into engagement with the at least one track tooth ( 13 ), and the cross brace ( 21 ) enabling a greater stroke of the wedge ( 20 ) in the unlocking position.   
     
     
         2 . The turnbuckle according to  claim 1 ,
 characterized in that   in the unlocking position, the cross brace ( 21 ) enables a stroke of the wedge ( 20 ) such that engagement of the wedge ( 20 ) in the track teeth ( 13 ) is at least reduced in the bracing position.   
     
     
         3 . The turnbuckle according to either  claim 1 or claim 2 ,
 characterized in that   in the unlocking position, the cross brace ( 21 ) increases the stroke of the wedge ( 20 ) such that the wedge ( 20 ) can be disengaged from the track teeth ( 13 ) in the bracing position.   
     
     
         4 . The turnbuckle according to either  claim 1, claim 2 or claim 3 ,
 characterized in that   the cross brace ( 21 ) can be moved in parallel with the clamping direction between an unlocking position and a locking position.   
     
     
         5 . The turnbuckle according to any one of  claims 1 to 4 ,
 characterized in that   the guide device ( 19 ) has a housing part ( 22 ) with at least two guide recesses ( 23 ) which are arranged at a distance from one another in the wedge-driving direction and through which the wedge ( 20 ) is passed, the guide recesses ( 23 ) guiding the wedge ( 20 ) in the wedge-driving direction, and the cross brace ( 21 ) being movably arranged on the housing part ( 22 ) transversely to the wedge-driving direction.   
     
     
         6 . The turnbuckle according to  claim 5 ,
 characterized in that   a wedge contact rail ( 24 ) is movably arranged in the guide recesses ( 23 ) such that the wedge contact rail ( 24 ) can carry out a lifting movement orthogonally to the toothed region ( 12 ), the wedge contact rail ( 24 ) being arranged in the guide recesses ( 23 ) on a side of the wedge ( 20 ) facing away from the toothed portion such that a lower side of the wedge contact rail ( 24 ) adjoins an upper side of the wedge ( 20 ), and the cross brace ( 21 ) being arranged on the housing part ( 22 ) such that the cross brace ( 21 ) adjoins an upper side of the wedge contact rail ( 24 ) facing away from the wedge ( 20 ), and the cross brace ( 21 ) limits the stroke of the wedge contact rail ( 24 ).   
     
     
         7 . The turnbuckle according to any one of  claims 1 to 6 ,
 characterized in that   the cross brace ( 21 ) has, on its lower side facing the wedge ( 20 ), a control surface ( 25 ) extending over at least some of the length of the cross brace ( 21 ) that limits the stroke of the wedge ( 20 ) in the guide recesses ( 23 ) to different values depending on the position of the cross brace ( 21 ).   
     
     
         8 . The turnbuckle according to  claim 7 ,
 characterized in that   the control surface ( 25 ) of the cross brace ( 21 ) has at least a first portion ( 25   a ) which, when the cross brace ( 21 ) is brought into contact with the upper side of the wedge contact rail ( 24 ) or the upper side of the wedge ( 20 ) in the locking position, limits a stroke of the wedge ( 20 ) in a direction orthogonal to the toothed portion ( 12 ) such that the wedge ( 20 ) can be brought into engagement with the track teeth ( 13 ), and the control surface ( 25 ) having a second portion ( 25   b ) which, when the cross brace ( 21 ) is brought into contact with the upper side of the wedge contact rail ( 24 ) or the upper side of the wedge ( 20 ) in the unlocking position, enables a greater stroke of the wedge ( 20 ).   
     
     
         9 . The turnbuckle according to  claim 8 ,
 characterized in that   the control surface ( 25 ) has a transition portion ( 25   c ) between the first portion ( 25   a ) and the second portion ( 25   b ).   
     
     
         10 . The turnbuckle according to any one of  claims 5 to 9 ,
 characterized in that   the cross brace ( 21 ) is arranged on an inner side of the housing part ( 22 ) of the guide device ( 19 ).   
     
     
         11 . The turnbuckle according to any one of  claims 5 to 10 ,
 characterized in that   the cross brace ( 21 ) has at least one, preferably a plurality of, in particular two, slots ( 26 ), by means of which the cross brace ( 21 ) is movably arranged on the housing part ( 22 ), preferably screwed, and the slots ( 26 ) limiting a movement of the cross brace ( 21 ) transversely to the wedge-driving direction.   
     
     
         12 . The turnbuckle according to any one of  claims 1 to 11 ,
 characterized in that   the cross brace ( 21 ) can move between two end positions transversely to the wedge-driving direction, the cross brace ( 21 ) assuming the locking position in the region of a first end position and the unlocking position in the region of a second end position.   
     
     
         13 . The turnbuckle according to any one of  claims 5 to 12 ,
 characterized in that   the housing part ( 22 ) and/or the cross brace ( 21 ) have a U-shaped pro-file in cross section.   
     
     
         14 . The turnbuckle according to any one of  claims 6 to 13 ,
 characterized in that   the wedge contact rail ( 24 ) has a contact surface on the lower side which forms a linear guide with a contact surface formed on the upper side of the wedge ( 20 ) in order to guide the wedge ( 20 ) in the wedge-driving direction, the two stop surfaces preferably being complementary.   
     
     
         15 . The turnbuckle according to  claim 14 ,
 characterized in that   the contact surface for the wedge ( 20 ) formed on the lower side of the wedge contact rail ( 24 ) has a depression ( 28 ) viewed in cross section, the depression ( 28 ) preferably being formed as a trapezoidal depression, as a triangular depression, as a depression having rounded edges, as a circular depression, as a rounded depression or by grooves, and/or, viewed in cross section, the depression ( 28 ) has a flat bottom ( 28   a ) from which side walls ( 28   b ) extend in the direction of the wedge ( 20 ), which run outward at an angle of 30° to 60°, preferably 45°, to the bottom ( 28   a ).   
     
     
         16 . The turnbuckle according to either  claim 14 or claim 15 ,
 characterized in that   the contact surface formed on the upper side of the wedge ( 20 ) has side walls which run complementary to the side walls ( 28   b ) of the contact surface of the wedge contact rail ( 24 ), the contact surface of the wedge ( 20 ) preferably having oblique side walls preferably extending at an angle of 30° to 60°, particularly preferably at an angle of 45°, corresponding to the side walls ( 28   b ) of the depression ( 28 ) in the wedge contact surface.   
     
     
         17 . The turnbuckle according to  claim 16 ,
 characterized in that   the contact surface of the wedge ( 20 ), with which the wedge rests against the contact surface of the wedge contact rail ( 24 ), has, viewed in cross section, two V-shaped projections ( 29   a ), between which there is a V-shaped depression ( 29   b ), the two V-shaped projections ( 29   a ) penetrating into the depression ( 28 ) in the contact surface of the wedge contact rail ( 24 ) and a side wall of each V-shaped projection ( 29   a ) adjoining one of the side walls ( 28   a ) of the contact surface of the wedge contact rail ( 24 ).