PURPOSE: To achieve high sealing performance of a device having vacuum differential exhaust means between a plurality of concentrically arranged vacuum sealing members by providing means for securing a predetermined amount of compression of each vacuum sealing member in consideration for the amount of deflection of a rotary flange sealing face.
CONSTITUTION: In a molecular beam scattering experimenting device, in order to keep e.g. an evacuated molecular beam scattering chamber 5 in an ultra-high vacuum, vacuum sealing members 1, having metal springs of large reaction fitted into four stages of a teflon cover, are fitted into vacuum sealing grooves 12 concentrically provided in a fixed flange 2. Thereover a rotary flange 3 is installed via a bearing 4 and vacuum exhaust grooves 10 are provided among the vacuum sealing member 1 to perform differential exhaust. In this case, the rotary flange 3 is provided with a rib 13 for preventing deflection so that the amount of deflection of the rotary flange 3 at each stage is less than a predetermined amount of compression of each vacuum sealing member 1. Therefore, a predetermined compressive force of vacuum sealing member 1 is secured at each stage and the device is allowed to exhibit its predetermined vacuum sealing performance.
KONDO YOSHIMASA
IGARASHI TOKUSHICHI
