PRODUCTION OF TURBINE TYPE VANE WHEEL

摘要

PURPOSE:To produce an extra-small-sized turbine type vane wheel having a small flow passage area with high accuracy and high efficiency by irradiating a powerful laser beam to a blank material from the radial direction thereof and chipping away the required part of the turbine flow passage by the laser energy. CONSTITUTION:The blank material 1 for the turbine vane wheel having a shaft part 3 at one end, a small-diameter part 4 at the other end and a large-diameter part in the mid-way thereof is rotated around the axial center in an arrow (a) direction. The laser beam B is intermittently and impulsively irradiated to the outside peripheral surface 6 thereof to pierce the turbine flow passage in a manner that the vane part remains in the prescribed part. The extra-small-sized turbine type vane wheel which is integrally formed with blades and shroud and is provided with the turbine flow passage processed to high accuracy is thus obtd. Processing of the flow passage to the shape which is wider toward the inside is made possible without increasing the area of an aperture 7 by irradiating the laser beam B at the changed (b) incident angle. The burn of the material 1 is preferably prevented by inserting a glass rod 9 having a recessed surface part 9a into the shaft hole 5 of the turbine wheel and leading the penetrated laser beam to the outside.