| 摘要 |
PURPOSE:To make it possible to gather magnetized powder in an operating gap by making use of a centrifugal force when the clutch is not excited by a method wherein the inner peripheral surface of a drive member near the operating gap is tapered or curved so that the diameter of the inner peripheral surface becomes larger toward the center of the drive member. CONSTITUTION:When a magnetic flux is generated in the operating gap 27 by energizing an electromagnetic coil 3, the powder 28 is magnetized and the torque of an engine is transmitted to a driven member 20 due to the connecting force of the magnetized powder 28 itself and the frictional force generating between the powder 28 and the operating surface of a clutch. When the clutch is in its unexcited condition, the drive member 1 rotates with the engine while the driven member 20 is at a standstill. In this case, the magnetized powder is rotated with the rotation of the drive member 1 and pressed against inclined surfaces 30a and 30b due to a centrifugal force. As the inclined surfaces 30a and 30b expand outwardly toward the operating gap 27, the magnetized powder 28 is guided along the inclined surfaces to gather in the operating gap 27. Therefore, when the clutch is excited again, the magnetized powder 28 comes to act quickly for the transmission of driving power so that it is possible to transmit a large torque from the beginning. |
