Patent ID: 8360106

Claim:
A one-way fluid control valve, comprising: a fluid channel defined by a channel wall forming a channel surface with upstream and downstream ends capable of containing and guiding flowable material, a pliant film device comprising top and bottom surfaces with upstream and downstream edges and capacity to closely conform to a channel surface and longitudinally positioned in and extending laterally across said fluid channel, attachment means capable of affixing at least said upstream edge of said film device to a portion of said channel surface so as to define a fluid passage whereby said fluid passage is arranged so as to pass all said flowable material between said top surface and said channel surface and a portion of said downstream edge of said film device affixed to a portion of said channel surface so as to leave a portion of said downstream edge unattached to said channel surface; and, a compressible spring in contact with a portion of said bottom surface of said film device so as to be sufficient in a relaxed state to positioning a portion of said top surface of said pliant film device against said channel surface so as to substantially prevent flow through said fluid passage by sealing off said fluid passage to said flowable material when fluidic pressure in an upstream channel is below a predetermined threshold pressure yet opening said passage to allow flow of said flowable material when upstream fluidic pressure exceeds said predetermined threshold pressure by compressing said compressible spring through pressure on said film device top surface sufficient to open a fluid passage between said film device top surface and said channel surface yet prevent backflow of flowable material motivated by positive downstream pressure whereby said backflow exerts pressure on said bottom surface of said film device sufficient to push corresponding said top surface against said channel surface so as to seal off said fluid passage thereby preventing said backflow material from passing upstream of affixed said pliant film device.