| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an electromagnetic coupling device capable of obtaining a specified transmission torque from the beginning of the use, and being miniaturized with low power consumption. SOLUTION: A manganese phosphate film 4a most of which consists of grains of not less than 10μm in grain size is formed through chemical treatment on an armature 4 of this electromagnetic coupling device. Since the grains of the manganese phosphate film 4a bite in a rotor 8 without any conventional adapting work, the transmission torque higher than that in the beginning of the use can be obtained. The device can thus be miniaturized, and the power consumption is reduced. In addition, the manganese phosphate film is non- magnetic, the armature 4 is rapidly detracted from the rotor 8 when an electromagnetic coil 9 is demagnetized, and the uncoupling as the electromagnetic coupling device becomes excellent. Since the film is formed through chemical treatment, the strength is larger than that by the treatment such as plating, and the powerful rustproof effect can be obtained.</p> |
