POWER TRANSMISSION DEVICE

PROBLEM TO BE SOLVED: To provide a power transmission device which can set transfer efficiency of power to an arbitrary value and which can transmit large power.SOLUTION: A shaft 30 is provided in a relatively rotatable manner with respect to a housing 20 by being inserted in a hole part 25 so that one end is located in an internal space 24 of the housing 20. A rotor 40 is provided inside the internal space 24 so as to be unable to relatively rotate with respect to the one end of the shaft 30, and so as to be able to come into contact with a first plate part 22 of the housing 20 by relatively moving in an axial direction. A functional fluid 50 is provided in the internal space 24, and it functions so that transfer efficiency of power between the housing 20 and the rotor 40 which are relatively rotating changes according to stimulation from outside. A function generating part 60 generates a suction force between itself and the rotor 40, sucks the rotor 40 to the first plate part 22 side and can impart stimulation to the functional fluid 50. Energization means 70 energizes the rotor 40 in a direction opposite to the direction in which the function generating part 60 sucks the rotor 40. 【課題】動力の伝達効率を任意の値に設定可能、かつ、大きな動力を伝達可能な動力伝達装置を提供する。【解決手段】シャフト３０は、一端がハウジング２０の内部空間２４に位置するよう穴部２５に挿通され、ハウジング２０に対し相対回転可能に設けられる。ロータ４０は、シャフト３０の一端に対し相対回転不能、かつ、軸方向に相対移動しハウジング２０の第１板部２２に当接可能なよう内部空間２４に設けられる。機能性流体５０は、内部空間２４に設けられ、外部からの刺激に応じて、相対回転するハウジング２０とロータ４０との間の動力の伝達効率が変化するよう機能する。機能発生部６０は、ロータ４０との間に吸引力を発生しロータ４０を第１板部２２側に吸引するとともに機能性流体５０に刺激を与えることが可能である。付勢手段７０は、機能発生部６０がロータ４０を吸引する方向とは反対の方向にロータ４０を付勢する。【選択図】図１