Patent ID: 7631852

Claim:
Normally closed passive microvalve, comprising: a fluid inlet; a fluid outlet; a deflectable closing element, which, in the closed state of the microvalve, is seated on a sealing lip, such that the fluid inlet is fluidically disconnected from the fluid outlet, and, in the opened state of the microvalve, is spaced apart from the sealing lip; and a deflectable holding structure, which is mechanically connected to the deflectable closing element, such that, between the same, a space exists, which is in fluidic communication to the fluid outlet, wherein an influence of force onto the deflectable holding structure and the deflectable closing element in a first direction provides an opening action, and an influence of force onto the deflectable holding structure and the deflectable closing element in a second direction provides a closing action, with the fluid inlet and the deflectable closing element being arranged such that a positive pressure at the fluid inlet exerts a force into the second direction, wherein an effective area of the deflectable holding structure, which, when a pressure is applied to the fluid outlet, causes a force into the second direction, is greater than an effective area of the deflectable closing element, which, when a pressure is applied to the fluid outlet, causes a force in the first direction, wherein the deflectable holding structure comprises a stiffened diaphragm structure, and wherein the deflectable closing element and the deflectable holding structure are configured such that the deflectable closing element may be lifted from the sealing lip by a negative pressure applied to the fluid outlet.