초록 ▼

A piston ventilator is disclosed herein which uniquely includes an oxygen blending module which supplies oxygen enhancement for aiding patients requiring respiratory treatment. The oxygen blending module supplies a preselected enrichment of oxygen to a piston and cylinder assembly wherein the amount

A piston ventilator is disclosed herein which uniquely includes an oxygen blending module which supplies oxygen enhancement for aiding patients requiring respiratory treatment. The oxygen blending module supplies a preselected enrichment of oxygen to a piston and cylinder assembly wherein the amount of oxygen permitted to flow therein is continuously monitored and controlled according to the volume above the piston in the cylinder as calculated by a controller. The oxygen blending module includes a flow sensor which monitors the flow of supplemental oxygen into the piston and cylinder assembly, and further includes a primary oxygen control valve which restricts the flow of oxygen through the flow sensor to the piston and cylinder assembly depending on the difference between the calculated desired amount of oxygen and the target amount of oxygen provided to the controller.

대표청구항 ▼

1. A patient ventilator comprising:a piston and cylinder assembly including a cylinder and a piston reciprocally received in said cylinder for movement along a retracting gas intake stroke and a protracting gas expelling stroke to define a variable volume chamber therebetween; a patient circuit for

1. A patient ventilator comprising:a piston and cylinder assembly including a cylinder and a piston reciprocally received in said cylinder for movement along a retracting gas intake stroke and a protracting gas expelling stroke to define a variable volume chamber therebetween; a patient circuit for delivering breathable gas from said piston and cylinder assembly to a patient during patient inhalation; a controller connected to said piston and cylinder assembly for receiving input corresponding to the position of the piston within the cylinder during the intake stroke; and an oxygen blending module fluidically connected to said chamber of said piston and cylinder assembly for controlling delivery of oxygen from an oxygen source to the piston and cylinder assembly for blending with the breathable gas in the chamber, said oxygen blending module including a first oxygen control valve operatively connected to said controller and a flow sensor for providing a signal to said controller representative of an amount of oxygen delivered from the first oxygen control valve, wherein said controller calculates a target amount of oxygen in said piston and cylinder assembly based on the position of the piston during the intake stroke, calculates a difference between said target amount and a calculated actual amount of oxygen delivered past said flow sensor based on the signal provided by the flow sensor and directs a control signal for opening and closing the first oxygen control valve based on said calculated difference during said intake stroke.