ROLLER EXPANDER FOR MACHINING HOLES OF INTRICATE SHAPE Russian patent published in 1994 - IPC

FIELD: mechanical engineering. SUBSTANCE: expander comprises body with a separator whose slots accommodate free-installed deforming rollers radially-drawn together, and supporting member. The latter is free-mounted in axial hole of the separator in the form of perforated supporting bushing made of a material with shape memory. Memory of bushing consists in changing its cross-sectional shape from regular polyhedron with rounded apices and the number of sides equal to the number of deforming rollers, to a circle and back. Rollers may be of sectional construction and clamped together by split spring rings or by rings made from a material with shape memory. Supporting bushing may be of a variable section along its axis, may be cut into individual rings, and made of a magnetized ferromagnetic material possessing shape memory. EFFECT: improved design. 9 cl, 6 dwg