초록 ▼

A portable mechanical ventilator uses a constant-speed compressor compressor and a recirculating bypass circuit. Bypass flow is governed by a spring-biased bypass valve so connected to both the inlet and the outlet of the main flow control valve as to maintain a differential pressure across the flow

A portable mechanical ventilator uses a constant-speed compressor compressor and a recirculating bypass circuit. Bypass flow is governed by a spring-biased bypass valve so connected to both the inlet and the outlet of the main flow control valve as to maintain a differential pressure across the flow valve sufficient to operate the ventilator with minimal energy consumption. The flow valve is operated by a microprocessor in accordance with empirically derived lookup tables to both produce the desired air flow and provide a measure of that air flow.

대표청구항 ▼

[ What is claimed is:] [15.] In a ventilator for patients needing assistance in breathing, a self-regulating flow control system, comprising:a) a flow valve having an inlet and an outlet and defining a gas flow path between the inlet and the outlet, the flow valve including a valving element in the

[ What is claimed is:] [15.] In a ventilator for patients needing assistance in breathing, a self-regulating flow control system, comprising:a) a flow valve having an inlet and an outlet and defining a gas flow path between the inlet and the outlet, the flow valve including a valving element in the gas flow path that is movable through a plurality of positions, each of which defines a specific cross-sectional area of the gas flow path, whereby a differential pressure is developed between the inlet and the outlet, and a gas flow rate is generated through the outlet that is a function of the cross-sectional area of the gas flow path;b) a pressure transducer in communication with the inlet and the outlet so as to generate a differential pressure signal indicative of the differential pressure; andc) a controller arranged to control the position of the valving element, the controller receiving the differential pressure signal and a position value indicative of the position of the valving element, wherein the controller, in response to the position value and the differential pressure signal, adjusts the position of the valving element for closed loop control of the gas flow rate.