| 摘要 |
<P>PROBLEM TO BE SOLVED: To improve opening/closing resolution of a valve element by specifying a low aperture range for a motor type EGR valve. <P>SOLUTION: This EGR valve 1 includes: a valve seat 4; a valve element 5 capable of abutting on the valve seat 4; a valve shaft 6 extending from the valve element 5; a motor 7 including a rotor 23; and a screw mechanism 8 arranged between the rotor 23 and the valve shaft 6, and including a male screw 24a and a female screw 28a screwed to the male screw 24a. The aperture of the valve element 5 with respect to the valve seat 4 can be changed by moving the valve element 5 by moving the valve shaft 6 in the axial direction by a screwing relationship between the male screw 24a and the female screw 28a by rotating the rotor 23 of the motor 7. The thread of the male screw 24a is separated from the thread of the female screw 28a in the low aperture range of the valve element 5, and the lower end face of a rotor body 28 and the upper surface of a spring receiver 9 is devised in terms of shape so that the movement percentage change of the valve shaft 6 in the axial direction in the low aperture range of the valve element 5 is reduced relative to the movement percentage change of the valve shaft 6 in the axial direction in an intermediate aperture range and a high aperture range of the valve element 5. <P>COPYRIGHT: (C)2013,JPO&INPIT |
