US Patent 7322556 Pinch valve for regulating fluid flow

A pinch valve for regulating fluid flow includes a close mechanism for closing a sleeve by pinching its sides together. The pinch valve also includes an open mechanism integral with the close mechanism for opening the tube by urging the sides apart. The open mechanism pushes against the ends of the closure in the sleeve as the tube is being opened. In one embodiment of the invention open cams push against the end of the closure, and in another embodiment open followers, which are part of a four bar linkage, push against the sides of the sleeve.