| 摘要 |
A part(26) of a silicon wafer(20), etched to form an annular sealing ring(44) and suitable chambers, acts as an exit (regulating) valve of a micropump e.g. supplying medicinal injection fluid. In the closed position the sealing ring presses against a lower glass wafer surface(2). When the valve has fully opened by enforced change of shape, contact occurs between an electrode (68), on the upper side (56) of the valve wafer and grounded externally through a conductor (70), and an electrode (54) on the lower side of an upper glass wafer(32) supplied from a voltage source through a resistor. Contact- is detected by collapse of the voltage between the electrodes. AN alternative detection system uses the capacitance between the valve wafer and the electrode on the upper glass wafer.
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