PURPOSE: To improve the responsiveness and the stability by providing a plurality of through holes in a center wall partitioning to form the first and the second pressure chambers in a contracting mechanism to supply the driving pressure to a valve, and fitting a valve body which is spring-energized in the opposite direction respectively.
CONSTITUTION: The center part of a case 18 of a variable contraction 17 is partitioned by means of a center wall 21 to form the first pressure chamber 22 to supply air pressure and the second pressure chamber 23 to output the driving pressure, and through holes 26A, 26B are formed in the center wall 21. The first pressure chamber 22 is connected to a control relay through a connection hole 19, and the second pressure chamber 23 is connected to a valve driving part through a connecting hole 20. A valve body 25 which is energized by a spring 28A in the closing direction to the second pressure chamber 23 side is fitted to the through hole 26A, and a valve body 27 which us energized by a spring 28B in the closing direction to the first pressure chamber 22 side is fitted to the through hole 26B respectively.
KIMURA ATSUSHI
YAMAGUCHI MASAAKI
HAYASHI HIROSHI
KUBOTA RYUSAKU
MIDORIKAWA MINORU
KASAHARA YASUO
INOUE AKIRA
