To provide a pressure reducing exhaust valve which is applicable to a pressure reducing device having only one exhaust passage (a main exhaust passage), fast in exhaust velocity and capable of suppressing the soaring of particles, and also to provide a pressure reducing device using a pressure reducing exhaust mechanism including the same.
The pressure reducing exhaust valve 10 is attached in a portion of the exhaust passage 5 with one end communicated with a vacuum chamber 2, and the other end with a vacuum pump 4. The exhaust valve 10 also includes: a pipe part 11 connected to an exhaust passage 5; an on-off valve 12 accommodated in the pipe part to open and close the exhaust passage 5; a porous body 13 with vent pores provided in the on-off valve 12; and a screening amount regulation part 10B, which is provided in the exhaust passage at the upstream or downstream side of the on-off valve 12 to make the screening area of the exhaust passage 5 variable.
IWASAKI TAKESHI
HASHIMOTO YUTAKA
Rie Ishimura