Abstract
As the theme of fuel oil saving has been recently highlighted together with the theme of man power saving and that of reliability in ships, systems driving large propellers of super-low speed such as 50 rpm by low speed two cycle diesel engines are becoming systems of main stream.
Electromagnetic gears can be thought as the most suitable power transmitting device installed between such super-low speed propellers and low speed diesel engines.
One of the most excellent special features of the electromagnetic gears is that starting and reversing of propellers, particularly turning from normal direction running of propellers to reverse direction running can be easily carried out.
In general, turning over of revolving direction of a propeller is necessary in case of crush astern and operation in port of a vessel. There are two methods of the turning over of propeller direction by electromagnetic gears, as follows: One is a method in which the direction of the propeller can be turned over while the prime mover connected with the gear is driving keeping the rotating direction of the prime mover constant, and the other is a method in which the direction of the propeller is turned over by changing the rotating direction of the prime mover.
Consideration, calculation and results of tests in connection with reversing of propeller by the electromagnetic gear of the rating capacity 16, 000 ps 430/107.5 rpm are described in this paper.
