Abstract: A device for transmitting pulsed axial percussions to a drill (12) and including a housing (2) one end of which is releasably connectable with a housing (3) of a hand-held rotary drill, a rotation transmitting element (7, 9) rotatably supported within the housing (2) and operatively connected with a rotatable spindle (4), which projects from the rotary drill housing (3), for joint rotation therewith, a chuck (11) provided at an end of the device housing (2) opposite to the one end for receiving the drill (12), a reciprocating hammer member (15) movable into an abutting engagement with a trailing end of the drill (12), and a hammer mechanism (17-20; 21-24) arranged within the device housing (2) for imparting pulsed axial percussions to the hammer member (15) and connected with the rotation transmitting element (7, 9) for generating the pulsed axial percussions.

Abstract: Homogeneous thermoplastic bituminous compositions containing up to 25 parts by weight of ethylene-.alpha.-olefin rubber, e.g. ethylene-propylene rubber, saturated or unsaturated, exhibit improved properties for all asphalt applications, e.g. pipe coating, roads, roofing, etc. The compositions are produced by heating and agitating the bitumen and rubber at above 170.degree. C., preferably 180.degree.-240.degree. C., or by subjecting the rubber to premastication before admixture with the bitumen at lower temperatures. Cross-linkable rubbers can be cross-linked in the bituminous compositions to yield high tensile strength final products.