Patent attributes
A valve for a plug passage features opposed perforated magnetic discs that repel each other to stay apart allowing flow through the openings of the spaced discs. When a predetermined flow rate is exceeded, the magnetic repelling force is overcome and one disc moves toward the other to shut off flow as contact between the discs closed the openings between them. One way is to offset the openings and guide the moving disc axially while rotationally locking the moving disc. Another way is to spirally guide the moving disc so that openings initially aligned rotate out of alignment. One or more edge slots can be provided in each disc to sweep out debris that can settle between the discs that would otherwise impede the moving disc from contacting the stationary disc for passage closure.
