| 摘要 |
A flow rate control valve 1 comprises a first sleeve 4 and a second sleeve 5 fitted into an inner periphery of a housing 3. The both sleeves 4 and 5 have inner end faces 4d and 5d which are disposed in abutment against each other while being displaced from each other radially, thereby forming annular stepped end faces 4d' and 5d' on a common plane. An edge of the stepped end faces define a first seat S1. The valve body 6 has an outer peripheral surface which is formed as a beveled surface, which defines a second seat S2. The second seat S2 of the valve body 6 is disposed in linear contact with the first seat S1 to close a flow path in a gas passage 2. <??>With this arrangement, a seal leakage when a butterfly valve 7 is closed can be reduced in comparison to the prior art. <IMAGE> |
