Abstract: Hydraulic clamp bushing (13, 14) having a double walled sleeve (7), a hydraulic pressure medium which is trapped in a chamber (5) between the sleeve walls, and a mechanism for pressurizing the pressure medium. One, or both, sleeve walls (7) is/are formed for expanding radially outwards and/or inwards when the pressure medium is pressurized, whereby the clamp bushing is clamped to a shaft, a hub or a similar object, in particular a rotary shaft (17, 18). The pressure medium chamber (5) is formed with angularly inwards or sigma formed bushing ends (9) designed so that the ends are straightened up as a first stage when the clamp bushing is pressurized, whereby the axial ends of the bushing facing the shaft (17, 18) are pressed to the shaft (17,18) thereby providing a straightening up of the bushing (13, 14) on the shaft before the intermediate portions of the sleeve are pressed to the shaft (17, 18).

Abstract: Hydraulically actuatable friction clamp coupling of the type which can be used for clamp connecting a sleeve (2) to a drive shaft (3). The clamp coupling includes a shape deformable inner ring (4) which is adapted to engage the sleeve (2), and which, at the outer surface thereof, is formed as a double, counter directed screw having two screw portions (8, 9) which meet substantially at the longitudinal center of the inner ring (4). The screw flange sides of the screw portions have the shape of saw tooth formed cone surfaces (10) as seen in an axial cross section. The outer rings (5, 6) which, at the inner race thereof, are formed with screw like cone surfaces (11) which are saw tooth shaped in a cross section view, match the cone surfaces (10) of the inner ring (4).

Abstract: Each of two parts has a friction surface engaged under a force against a friction surface on the other to inhibit relative motion between the parts in one direction. One of the parts has at its friction surface strip-like hard zones which extend transversely to that direction and which are laterally spaced apart to have a strip-like soft zones between them. The material of that one part is substantially harder in the hard zones than in the soft zones. The material of the other part, at its friction surface, is of such hardness that under the force urging the friction surfaces together, the differences in hardness as between the hard zones and the soft zones of the one part tend to deform the friction surface of that other part into undulations that increase friction in the mentioned direction without substantially increasing friction transversely to that direction.

Abstract: A method and apparatus for the assembly of long objects (1) such as rollers, cylinders, elongated tools, for example surface cutters, on a rotating shaft (2) with the aid of two expander bushings (3, 4), each an integral part made up of an inner wall (7) and an outer wall (8), which between them form a pressure cavity (9), which is filled with a liquid or plastic pressure medium, and where the expander bushings (3, 4) each have a flange (10) arranged to contact each end surface (11) of the long object (1) which shall be assembled.