| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an efficient, durable and low-cost differential gear having a simple structure and conforming to the control operation of a user. SOLUTION: In this application, an electromagnetic clutch 29 and a ball (cam)-ramp operation type friction clutch device 17 controlled by the electromagnetic clutch 29 are provided. The electromagnetic clutch 29 comprises an input joint member 35 and an out output joint member 43, and a transmission work quantity between both the members is defined by a magnetic reaction medium 42 filled into a gap 40 thereof. The medium 42 is concretely a magnetic particle or magnetic fluid, the viscosity shearing force of the medium 42 changes based on the strength of a magnetic field 90. Since the output joint member 43 operationally engages with one of ball ramp actuators 31, the transmission of force between the input and output joint members 33 and 43 generates the relative rotation of the actuators 31. Accordingly, a cam operation compressing friction discs 65 and 67 in the device 17 is carried out, so that torque is transmitted in the device 17.</p> |
