Advanced Technology Institute of Commuter-helicopter, Ltd.

Tatsuhiko Goi

Eiichi Yamakawa

Kouji Kawakami

Nobuyoshi Yamauchi

Nobuyuki Yamauchi

A constant speed drive apparatus for an aircraft generator comprises an input shaft for receiving drive torque from an aircraft engine, a traction speed change mechanism of continuously-variable speed change ratio which is coupled to the input shaft, an output shaft for supplying the aircraft generator with drive torque which is changed in speed by the traction speed change mechanism, and a control computer for controlling the speed change ratio of the traction speed change mechanism to maintain the output shaft at a predetermined rotational frequency. With such constitution it is possible to achieve a small and lightweight constant speed drive apparatus having a high transmission efficiency.

Constant speed drive apparatus for aircraft generator and traction speed change apparatus

In a variable mode of operation in which clutches are locked and a clutch and a brake are unlocked, the power of an input shaft is branched to a traction transmission mechanism. By contrast, in a fixed mode of operation in which the clutches are unlocked and the clutch and the brake are locked, the power of the input shaft is not branched to the traction transmission mechanism. In this way, the fixed mode and the variable mode are selectively used, whereby noise reduction and enhanced fuel efficiency can be attained. According to this configuration, it is possible to provide a power transmission apparatus for helicopters in which the number of rotations of a main rotor or a tail rotor is continuously varied while maintaining the number of rotations of an engine constant.

Power transmission apparatus for helicopter

Power transmission device for helicopter

Each engine is directly coupled to an engine deceleration device composed of a traction speed change mechanisms and a planetary speed change mechanism, and is decelerated at a desired speed change ratio, and rotate and drive a collector gear and a main rotor shaft. The collector gear rotates and drives accessories and a tail rotor through a second traction speed change mechanism changing speed in inverse number of the speed change ratio of the traction speed change mechanisms. Thus, the rotating speed of the engines can be continuously decelerated at an arbitrary speed change ratio, and an engine deceleration device of small size, light weight, and low loss is realized. At the same time, a power transmission device for helicopters capable of changing the rotating speed of the main rotor at a constant engine rotating speed is realized.

Growing community of inventors

Kakamigahara, Japan

Tatsuhiko Goi