| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a motor-driven power steering device provided with an inexpensive torque limiter corresponding to temperature change by a simple structure. SOLUTION: The torque limiter 20 for this motor-driven power steering device is provided with a magnetic case 21 fixed to an output shaft 3 of a motor, a boss 31 made of a magnetic body arranged coaxially with the case so as to relatively rotate and connected to a driven shaft, and a permanent magnet member 35 arranged between the case 21 and the boss 31 for coupling them by magnetic force. The permanent magnet member 35 is annular and it is anisotropically polarized in an axial direction. Its residual induction can have a negative temperature coefficient, or wear resistant material layers can be inserted between the permanent magnet member 35, and the case 21 and the boss 31.</p> |
