The Z-type propulsion unit consists of the power transmission system, steering
system and remote control system. The Z-type propulsion unit has a function of full 360 degrees swivelling of propeller thrust around the vertical axis, and so no conventional steering system is required for the vessel.
Since this propulsion system was developped about 40 years ago for small vessels, it has grown up largely and today it is recognized as a reliable and full size propulsion system for many kinds of vessel, tug boat, offshore work boat, fishing boat, passenger boat and cargo ship.
Niigata Engineering Co., Ltd. has manufactured total of more than 1800 units of Z-peller with fixed pitch propeller since the delivery of the first unit in 1969, and also we manufacture many models of high, medium and low speed 4-cycle marine diesel engines. Therefore we can supply the most suitable marine diesel engine for Z-peller drive.
In 1988, we developped new Z-peller under new technologies and lots of know-how
that we experienced for many years. Three models have been developped as new Z-peller series, those are ZP-11, ZF-21 and ZP-31 type. When we started the designing
of ZP-21 type, main targets were more compactness, lighter weight and more simple construction than original Z-peller series.
§2. Outline of Z-peller System
2-1. Main Particulars
Table-1 shows the main particulars of new Z-peller series. We provide each three kinds of reduction gear ratio for ZP-11 and ZP-21 models, then suitable reduction gear ratio can be choosen to fit for the main engine power and speed.
2-2. Power Transmission (Fig. - 1 & 2)
Z-peller has a mechanism that the main engine's power is transmitted to the propeller through 2 sets of bevel gear unit, input shaft, vertical shafts and propeller shaft as shown on Fig.-1
