| 摘要 |
<p>After the assembly comprising the ultrasound electrode (8) and its casing (16) has been moved to the shotfiring position, the electrode (8) is vertically moved so that its vibrating surface (8a) is at the level of the lateral opening of the cell (2). At least three successive firings are made on the wall (2C) by inverting the sense of rotation of the rotor (1) rim at each approach of one of the ends of the cell. Method of surface treatment and application of pre-constraint compression by shotfiring the wall (2C) of an annular cell (2) sensibly in the shape of a dovetail, formed on the periphery of a rotor (1) rim. The cell (2) is open to the exterior by a lateral annular opening and has at least two ends (5A,5B) which respectively end in an opening (5) into which is fitted a rotor blade. The treatment method includes the following stages: (a) a load of preferably 1 mm diameter balls are placed on the surface of a vibrating surface (8A) of an ultrasound electrode (8) previously fixed in an intermediate position in a casing (16) surrounding the vibrating surface. The casing has opposite shutter ridges (14A,14B) which slide into the cell (2); the cell opening (5) is placed opposite the ultrasound electrode; the electrode and its casing are moved vertically towards the cell opening so as to place them in a shotfiring position in which the shutter ridges are in contact with the base of the cell; the rotor rim is turned around its axis so as to bring the shutter ridges up to a first end (5A) of the cell so as to form a closed mobile enclosure for the balls (10), and; the surface (2C) of the cell is bombarded with balls (10) inside the enclosure by means of the electrode which is excited by an ultrasonic oscillation generator, and by regular turning of the rotor rim around its axis the mobile enclosure is moved to the second end (5B) of the cell.</p> |
