Mitsui Engineering and Shipbuilding Company Limited

Dai-ichi Electric Co., Ltd.

The Tsurumi-seiki Co., Ltd.

Shogo Miyajima

Shuji Ueki

Hiroshi Satoh

Hirohumi Doi

Kenzo Hasegawa

Kunio Nakano

Takashi Kawaguchi

Hiroyuki Nakagawa

A wave power generation device for synchronizing a vertical movement of a float with all the wave periods, and a method of controlling the same. The device has a controller which controls a torque of a power generator, and the controller is configured to estimate a displacement and a speed of a float from data of a rotation number or a rotation speed of the power generator, to estimate a wave period from the displacement and the speed, and to determine a displacement coefficient corresponding to the wave period from a data table stored in advance, and to transmit a calculated product of the displacement coefficient and the displacement as a torque command to the power generator so as to control a torque of the power generator.

Wave power generation device and method of controlling the same

To provide a winding mechanism and a trawling apparatus capable of eliminating an excessive tension or slack generated in a wire wound around a drum and keeping the tension or wire length of the wire constant. A winding mechanism with tension control function includes a reversibly rotatable liquid-pressure motor rotating a drum having a wire wound therearound, a liquid-pressure pump coupled directly with the liquid-pressure motor and supplying hydraulic oil, and an electric motor rotating to drive the liquid-pressure pump. The winding mechanism further includes a control unit controlling a torque of the electric motor based on a variation in load current of the electric motor and winding off or winding up the wire to keep the tension of the wire at a set value.

Winding mechanism with tension control function and trawling apparatus

A hoisting device can be small-sized and energy can be saved. A hoisting deviceaccording to the present invention has a hoistand a control unit. The hoistrotates a drumhaving a wirewound thereon by an oil pressure motorrotatable in normal and reverse directions. To the oil pressure motor, operating oil is supplied from an oil pressure pump. The oil pressure pumpis a two-way discharge fixed capacity type, and rotated by a servomotor. An acceleration/displacement transducerin the control unitfinds a moving direction and a moving speed of a wire hanging point in the vertical direction from an output signal of an acceleration sensor. The control unitoutputs a drive control signal of the servomotoraccording to a paying-out speed or a rolling-up speed of the wireoffsetting the vertical motion of the wire hanging point caused by the heaving of a hull based on a speed instruction Vi of the paying-out or rolling-up speed of the wire, a detected signal of the acceleration sensorand a detected signal of a wire speed sensor

Hoisting device with vertical motion compensation function

Growing community of inventors

Akishima, Japan

Shogo Miyajima