of the bandlike support element 12 the legs 32 and 34 of the u of the connection device 16 extend on the side of the base 30 of the u remote from the support element 12 the pivot pin 22 is supported in the legs 32 and 34 of the u the fastening of the connection device 16 to the support element 12 is done with the aid of a welded connection which will be described in further detail hereinafter while in the drawings the connection device 16 is substantially u shaped cross section this is not necessary for the present invention the connection device 16 must have only the base 30 or a base like part which can be flatly placed on the support element 12 and connected with the latter as a positioning aid the base 30 of the connection device has a protrusion 38 extending from the side remote from the legs 32 and 34 of the u and this protrusion has two shoulders 40 and 42 pointing in opposite directions u2014 in the longitudinal direction of the support element 12 these shoulders 40 and 42 are each assigned a respective counterpart shoulder 44 and 46 of the support element and the counterpart shoulders are embodied at a recess 48 of the support element 12 because these shoulders point in the longitudinal direction of the support element a positive connection is obtained between.