| 摘要 |
<p>An elevation-type thruster apparatus is provided with: a pair of racks (31) of the required height, disposed on outer surfaces of a canister (21) and having teeth portions (32) with a predetermined pitch in the vertical direction; guide members (40) which are provided along the racks (31); and a pair of elevation apparatuses (30) which raise and lower the canister (21) within an elevation path (2). Each of the pair of elevation apparatuses (30) comprises: a pair of catches (36,38), upper and lower, which each independently engage and disengage with teeth portions (32) of the rack (31) at positions vertically spaced apart; a pair of frames (34,35), upper and lower, equipped with the catches (36,38); and an elevation cylinder (33) which is provided between the frames (34,35). This elevation cylinder (33), with respect to one frame (34) which is affixed to the elevation path side, raises and lowers the other of the frames (35) as guided by a guide member (40). Thus, the elevation-type thruster apparatus is capable of raising a thruster above the waterline surface.</p> |
