| 摘要 |
<p>PURPOSE:To obtain stable characteristics by forming thin films made of non- magnetic metal on surfaces of a frictional plate which is a part of an electro magnetic circuit, thereby keeping high penetrating ratio of magnetic flux, and suppressing transmission torque change of a electromagnetic clutch in respect to change of differential rotation between input and output. CONSTITUTION:In a rear differential device 7, in case that coil current is applied to a electromagnetic 71, magnetic flux penetrates frictional plates 57, 59 for attracting an armature 69, so that a pilot clutch (electromagnetic multiple disc clutch) 55 is fastened and a cam ring 53 is connected to a differential case 21. When differential rotation is generated between bilateral rear wheels, a differential torque is applied to a ball cam 61, so that a main clutch 51 is fastened through pinion carriers 47, 49. Differential operation of a differential mechanism 35 is regulated, accordingly. In such a construction, for instance, thin films made of non-magnetic metal such as chrome nitride are formed on both surfaces of the frictional plate 57 on an outer side of the pilot clutch 55 with a thickness of 3m by vacuum deposition method.</p> |
