VACUUM AND PRESSURE RELEASE VALVE-RELATED APPARATUS TO CHIP TANK PERFORMING PRELIMINARY ORDINARY PRESSURE STEAM TREATMENT AND METHOD FOR USING THIS

摘要

PURPOSE: To provide a method and device enabling the pressure difference within a chip bin to be maintained irrespective of the case in a vacuum or pressurized state when put to a pressure condition greater than a desired level. CONSTITUTION: Extending upwardly from the top 14 of a chip bin is a vertical section 21 of conduit, an elbow section 22, and a horizontal section 23. A door guide frame 29 is so designed that a door opening 30 therein is disposed in the horizontal section, precluding passage of gas through the horizontal section except through the door opening. A pivot pin 32 mounts a door 31 at its top so that the door 31 normally assumes a vertical orientation closing off the opening, and it is adjustably biased into that orientation by a counterweight mechanism 48. The counterweight is made adjustable by the number of weight discs 58 mounted on the vertical section of a rod having external screw threads 50. The horizontal section of the rod is connected by a flange 53 to a flange 41 of the pivot pin 32; thereby the pressure difference between the chip bin and the surrounding environment is maintained at about 2 psig.