Disposable Vacuum Filtration Apparatus Capable of Detecting Microorganisms and Particulates in Liquid Samples

Abstract

A vacuum filtration apparatus for detecting microorganisms and particulates in liquid samples. The apparatus includes a base, an absorbent pad, a filter means, a funnel and a lid. The funnel is releasably attached to the base, and may contain an integral flexible seal for releasably sealing the filter means to the base. The outer wall of the lid may be segmented to make it flexible, this flexibility allows it to be releasably attached to the funnel or the base. The apparatus is designed so that any funnel will fit any base, and any lid will fit any base or any funnel when all parts are manufactured to normal tolerances. The apparatus may contain a means to keep the filter means wrinkle free in both the dry and wet states.

1 . A vacuum filtration apparatus comprising:
 a base including an outlet port capable of being adapted to a vacuum source,   a funnel disposed above the base,   a filter support means disposed upstream of the outlet port,   a filter means disposed upstream of the filter support means, said filter means being sealed to the vacuum filtration apparatus, thereby preventing unfiltered liquid from bypassing the filter means, thereby preventing the flow of unfiltered liquid through the outlet port,   with the interior of the funnel capable of holding unfiltered liquid upstream of said filter means,   with said funnel including one or more lid clamp tabs protruding from the upper portion of the outside wall of said funnel, with the one or more lid clamp tabs including a top surface, an end surface, and a bottom surface,   with said vacuum filtration apparatus further including a lid having an outer wall, with the shape of an inner surface of the outer wall of the lid matching the shape of the upper portion of the outside wall of said funnel, with the height of the inner surface of the lid being greater than the distance between the bottom surface of the one or more lid clamp tabs of the funnel and the top wall of the funnel,   with the lid further including a plurality of slots in the outer wall, with each slot creating a gap in the bottom surface of the outer wall, with the height of the slots being less than or equal to the height of the inner surface of the outer wall, with the slots dividing the outer wall into a plurality of segments, with the number of slots being sufficient to allow the outer wall to flex when the lid is made from a rigid material,   with at least one of said segments of said lid including an inward projection that protrudes inward from the bottom portion of inner surface of the at least one segment, with the at least one inward projection including a top surface, an end surface, and a bottom surface,   with either the top surface of the one or more lid clamp tabs of the funnel, or the bottom surface of the one or more inward projections of the lid, or both including a sloped surface, with the value of the angle of the slope of at least one of these surfaces being sufficiently greater than zero degrees, so that the one or more segments of the outer wall of the lid that include an inward projection will be forced to bend outward as the bottom surface of said one or more inward projections of the lid are pressed down against the top surface of the one or more lid clamp tabs of the funnel, until the end surface of said inward projections of lid presses against end surface of the one or more lid clamp tabs of funnel, and then as the lid is further pressed down onto the funnel, the segments of the outer wall of the lid that include inward projections will snap inward with at least a portion of the top surface of the one or more inward projections of the lid disposed below at least a portion of the bottom surface of the one or more lid clamp tabs, with the value of gap between end surface of the at least one inward projection of the lid, and top outside wall of the funnel, being equal to, or greater than zero, but less than the width of the one or more lid clamp tabs of the funnel, thereby creating a sufficient overlap between the end surface of the one or more lid clamp tabs and the end surface of the one or more inward projections, with the value of the gap between the bottom surface of the one or more lid clamp tabs of the funnel and the top surface of the one or more inward projections of the lid being equal to or greater than zero,   thereby preventing the lid from being accidentally disengaged from the funnel,   and thereby allowing the end user to attach the lid to the funnel, by simply placing the lid onto the top of the funnel, and then pushing down on the lid.