| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a rotary-type four-way switch valve suitable to reduction in size and weight and to mount in a vehicle for reducing cooling medium flowing noises resulting from the switching operation of a main valve while preventing the displacement of the valve position. Ž<P>SOLUTION: A planetary gear mechanism 140 is arranged in a rotor 40 as part of a stepping motor for the four-way switch valve 1. The rotation of the rotor is transmitted to a sub valve 60 and the main valve 70 in a greatly speed-reduced manner. The sub valve 60 and the main valve 70 are gently opened to suppress cooling medium flowing noises during switch. Sufficiently torque is produced in the turn of the sub valve 60 and the main valve 70 to actualize the compact construction of a driving part. Besides, even when the rotor 40 is reversely rotated resulting from the characteristics of the motor during stopping the main valve 70, the reverse rotation of the rotor 40 is reduced by an equivalent of a speed reduction ratio and absorbed by backlash existing in the planetary gear mechanism 140, whereby there is no displacement of the main valve 70 to prevent the leakage of cooling medium. Ž<P>COPYRIGHT: (C)2010,JPO&INPIT Ž
|
