Patent ID: 8575803

Claim:
A magnetic coupling device comprising: a first rotating member and a second rotating member, each of which includes a plurality of magnets arranged such that magnetic poles of the magnets adjacent in a direction of circumference are different from each other, that are arranged such that their respective interaction surfaces are opposed to each other while being separated from each other and that are rotatable about a common rotation axis that extends in a direction orthogonal to the interaction surfaces, to transmit torque from one of the first and second rotating members to the other using a magnetic force that is generated between the interaction surface of the first rotating member and the interaction surface of the second rotating member, either one of the first and second rotating member being rotatably connected to the rotation axis via a bearing; a first magnetic force unit that, when transmitting the torque, causes magnetic repulsion in the direction of the rotation axis between an inner circumference area on the interaction surface of the first rotating member and an inner circumference area on the interaction surface of the second rotating member, the inner circumference areas being in the vicinity of the rotation axis; and a second magnetic force unit that, when transmitting the torque, causes magnetic attraction in the direction of the rotation axis between an outer circumference area on the interaction surface of the first rotating member and an outer circumference area on the interaction surface of the second rotating member, the outer circumference areas being radially outward with respect to the first magnetic force unit, wherein the second magnet force unit is configured to cause the magnetic attraction in the rotation direction of the rotation axis between the outer circumference areas that is greater than a magnetic repulsion in a rotation direction of the rotation axis that the first magnetic force unit causes between the inner circumference areas.