Extendible screeds

Abstract

This invention relates to road paving machines. Such machines are known in which there is a screed extending across the rear end of the machine and comprising two parts lying one behind the other. One part, the first, is fixed (except that it may be tilted and vibrated) relatively to the rest of the machine and the other part lies behind the first and is slidable along the first to enable the overall width of the screed to be varied. The second part is conventionally one of two similar parts that can be slid in opposite directions outwardly from retracted positions to project beyond the ends of the first part so that when the overall width of the screed is a maximum, the second parts project one from each end of the first. In one form proposed for such apparatus, each second part is carried from the first by two telescopic supports extending in the direction of the width of the screed. The use of two supports is effective to prevent the second part from rotating about the axis of either of the supports and an object of the present invention is to enable only one telescopic support to be used while, at the same time preventing rotation of the second part about the axis of the support.