| 摘要 |
A process for simultaneously shaping and sharpening a cutting widow at the distal end of a tubular member of a rotary blade assembly. The assembly is provided with a stationary elongated outer tube, having a cutting window at its distal tip and includes a rotatable elongated inner tube having a cutting means at its distal tip. The window in the outer tube has a curvilinear profile defined by a peripheral rim surrounded entirely by a land surface which is inclined relative to the rim. The inclination of the land produces an area which tapers from a full thickness, where the land is adjacent to the cylindrical wall of the outer tube, to a sharp edge around the periphery of the window. The curvilinear window is produced by a manufacturing process which creates the window opening with a sharpened periphery at the same time that the land surrounding the opening is inclined. A preferred embodiment utilizes electrochemical grinding of the distal ends of the tubular member by a tool having a rotatable wheel with a perimeter in the shape of a groove of predetermined arcuate profile. <IMAGE> |
