Patent ID: 7635585

Claim:
A micro valve apparatus comprising: an upper substrate; an intermediate substrate; a lower substrate; channels as flow paths of a fluid, the channels formed between the upper and lower substrates; a valve hole which interconnects the channels; the valve hole formed in the intermediate substrate, wherein the valve hole includes a first diameter and a second diameter, the second diameter having a diameter greater than that of the first diameter; wherein the second diameter includes an third diameter having a diameter greater than the microbead; wherein a surface formed between the first diameter and the second diameter provides a contact region on the microbead for enhancing sealing of the valve hole; chambers for storing a variety of assay buffer and for chemical reactions; the chambers formed between the upper and lower substrates; a rotatable disk in which the channels, the chambers and the valve hole are formed; wherein the fluid in the channels flows from the center to edges of the rotatable disk by centrifugal force caused by the rotation of the rotatable disk; upper and lower electromagnets mounted on the top and bottom of exterior surfaces of the rotatable disk, respectively, opposite to each other; and a microbead which is moved upward or downward by the upper and lower electromagnets, to open and close the valve hole, thereby controlling fluid flow or quantity, wherein an upper channel connecting a first chamber to the valve hole is formed recessed to a first depth in the upper substrate, and a lower channel connecting a second chamber to the valve hole is formed recessed to a second depth in the lower substrate, wherein the first and the second chambers are interconnected with each other through the channels when the valve hole is opened, wherein the upper substrate has a confining groove which holds the microbead and prevents it from moving away when the rotatable disk rotates.