| 摘要 |
<p>A turbine (4) suitable for use in down-hole drilling and the like, and comprising a tubular casing (11) enclosing a chamber (18) having rotatably mounted therein a rotor (19). The rotor (19) comprises at least one turbine wheel (30a) with an annular array of angularly distributed blades (30). The blades (30) are orientated with drive fluid receiving faces (31) thereof facing generally rearwardly of a forward direction of rotation of the rotor (19), and a generally axially extending inner drive fluid passage means (14) generally radially inwardly of said rotor (19). The casing (11) also has generally axially extending outer drive fluid passage means (16), and one of the inner and the outer drive fluid passages (14, 16) are provided with outlet nozzles (17) formed and arranged for directing at least one jet of drive fluid onto the blade drive fluid receiving faces (31) as the blades (30) traverse the nozzle means (17) for imparting rotary drive to said rotor (19). The other of the inner and the outer drive fluid passages (14, 16) is provided with exhaust aperture means (28) for exhausting drive fluid from the turbine (4).</p> |
