| 摘要 |
PROBLEM TO BE SOLVED: To provide an electric power steering device capable of relaxing impact at a stroke end while always retaining steering properties well regardless of the state of steering operation. SOLUTION: The electric power steering device is provided with a rack position detection means 44 for detecting a position of a rack; a rack speed operation means 45 for calculating movement speed s of the rack; a memory means for memorizing a relationship of a rack speed s previously set near the stroke end of the rack and a motor attenuation control starting rack position where a distance from the stroke end becomes far in response to the rack speed s as a relation curved line C of a coordinate map; a checking means 46 for determining whether or not a combination position coordinate (s, p) of the rack speed s calculated by the rack speed operation means 45 and the rack position p detected by the rack position detection means 44 exceeds the relation curved line C; and a motor attenuation control means 41 for attenuation-controlling the motor based on a predetermined motor assist reduction ratio As when the checking means 46 determines that the combination position coordinate (s, p) exceeds the relation curved line C. COPYRIGHT: (C)2006,JPO&NCIPI |
