Patent ID: 7740247

Claim:
An atmosphere to vacuum compound sliding seal unit comprising: a fixed inner plate suitable for immovable attachment to and integration with a wall of a vacuum chamber, wherein said fixed inner plate has forward-facing and rearward-facing surfaces, preselected width and thickness dimensions, a limited length dimension, and a centrally disposed open slot whose span extends over not less than one half of said limited length dimension; an intermediate plate positioned adjacent to and slideable on-demand over said forward-facing surface of said fixed inner plate, wherein said slideable intermediate plate has forward-facing and rearward-facing surfaces, prechosen width and thickness dimensions, a length dimension substantially shorter than said limited length dimension of said fixed inner plate, and a centrally disposed cavity zone whose span is substantially less than said span of said open slot in said fixed inner plate; an outer plate positioned adjacent to and slideable on-demand over said forward-facing surface of said slideable intermediate plate, wherein said slideable outer plate has forward-facing and rearward-facing surfaces, predetermined width and thickness dimensions, a length dimension smaller than said length dimension of said intermediate plate, and a centrally disposed air-tight mounting suitable for the juncture and support of a feed-through member; a first sliding seal located between said forward-facing surface of said fixed inner plate and said rearward-facing surface of said slideable intermediate plate, said first sliding seal surrounding and hermetically enclosing the perimeter of said open slot in said fixed inner plate; a second sliding seal located between said forward-facing surface of said slideable intermediate plate and said rearward-facing surface of said slideable outer plate, said second sliding seal surrounding and hermetically enclosing the perimeter said cavity zone in said slideable intermediate plate; means for raising and lowering said slideable intermediate plate and said slideable outer plate on-demand; and a feed-through member of set dimensions attached to said air-tight mounting of said slideable outer plate, whereby the axial length of said mounted feed-through member extends through said cavity zone of said slideable intermediate plate and said open slot of said fixed inner plate concurrently, and thereby passes from an atmospheric environment into a vacuum environment.