초록 ▼

The present invention relates to a sample filtration device of the type employing differential pressure. An outer container filled with a sample to be filtered slidably receives a hollow plunger having filter media disposed near one end and sealing means disposed in an annular groove about the perip

The present invention relates to a sample filtration device of the type employing differential pressure. An outer container filled with a sample to be filtered slidably receives a hollow plunger having filter media disposed near one end and sealing means disposed in an annular groove about the periphery of the plunger. The annular groove of the plunger is formed by two components: an annular shoulder on a collector portion and the axial face of an annular ring formed in a retainer portion. The two portions are frictionally engaged to retain the filter in place and form the annular groove for the sealing means. This construction permits straight-pull molding of the component parts which eliminates mold mismatch flaws.

대표청구항 ▼

A differential pressure sample filtration device comprising: an outer container for receiving a fluid for filtering; and a hollow plunger dimensioned to be slidably received in said outer container and comprising: a first piece having at one end a reduced diameter portion forming an annular shoulder

A differential pressure sample filtration device comprising: an outer container for receiving a fluid for filtering; and a hollow plunger dimensioned to be slidably received in said outer container and comprising: a first piece having at one end a reduced diameter portion forming an annular shoulder, means for collecting fluid filtrate and filter means disposed between said one end of the plunger and said means for collecting fluid filtrate; and a second piece having an annular axial face and being dimensioned to be secured to said first piece such that the annular axial face and the annular shoulder cooperate to form an annular groove about said plunger, said annular groove being adapted for receiving a sealing means for forming a fluid seal between the outer container and the hollow plunger, wherein said second piece comprises a first annular ring dimensioned to slidably fit over said one end of said first piece, a second annular ring dimensioned to slidably fit into the hollow portion of said one end of the first piece to abut said filter means, and a plurality of legs connecting said first annular ring to said second annular ring.