To constantly hold a torque and use both a temperature 2 WD mechanism and a torque limiter mechanism serve by arranging a drain pin for opening a drain hole, while taking a balance gradually when it attains a prescribed toque level.
When it attains a prescribed torque level, the balance between oil pressure of a first high pressure chamber 76 and spring force of return springs 69, 70 is changed, and oil pressure of the first high pressure chamber 76 outdoes the spring force of the return springs 69, 70, and a communicating hole 56 is opened by a limiter pin 60 to regulate pressure. A balance between a oil pressure of the first high pressure chamber 76 and spring force of a drain spring 74, and oil pressure of a second high pressure chamber 78 is changed, oil pressure of the second high pressure chamber 78 is better than the oil pressure of the first high pressure chamber 76 and spring force of the drain spring 74, and a drain hole 73 is gradually opened by a drain pin 75. The drain pin 75 is acted with hydraulic balance, a torque is held constant, and can use both a temperature 2 WD mechanism and a torque limiter mechanism.
KATO TADAHIKO
NAKABAYASHI AKIRA
TAKASAKI TOSHIHARU
KUSUKAWA HIROTAKA
MURATA SHIGEO
NISSAN MOTOR
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