Volume limiting ventilator
First Claim
1. In a volume limiting ventilator having an inhalation phase and an exhalation phase in its operative cycle for use with a source of gas under pressure, an inlet adapted to be connected to the source of gas, a rigid canister, an expandable and collapsible bellows in said canister forming a chamber inside the bellows and in cooperation with the canister forming a chamber exterior of the bellows, a patient adapter adapted to be connected to the airway of the patient, means for connecting the patient adapter to the chamber within the bellows, flow path means for connecting the chamber exterior of the bellows and the chamber inside the bellows, transfer valve means mounted in said flow path means for controlling the flow of gases through the flow path means, a sequencing servo having an inlet connected to the inlet of the ventilator, an outlet, and a valve member movable between open and closed positions for controlling the flow of gases from the inlet to the outlet of the sequencing servo to cause the inhalation phase and the exhalation phase respectively of the ventilator, diaphragm-operated means for moving the valve member between its open and closed positions, means coupled to the sequencing servo for adjusting the forces applied to the diaphragm, a master venturi assembly and a sensing venturi assembly coupled to the flow path means both between the chamber exterior of the bellows and the transfer valve means, means for connecting the sensing servo assembly to the diaphragm-operated means of the sequencing servo so that pressure sensed by the sensing venturi assembly is supplied to the sequencing servo assembly, means connected between the outlet of the sequencing servo assembly and the master venturi assembly for supplying source gas to the master venturi during the inhalation phase, means connected between the inlet of the ventilator and the sensing venturi assembly for supplying source gas to the sensing venturi at the commencement of the exhalation phase, an exhalation valve assembly having an inlet connected to the patient adapter and an outlet vented to the atmosphere, means for supplying source gas from the sequencing servo during the inhalation phase to maintain the exhalation valve assembly in a closed position, a volume stabilizer valve assembly coupled to the master venturi assembly, said transfer valve assembly and said volume stabilizer valve assembly each having a valve member movable between open and closed positions and diaphragm-operated means for moving their valve member toward one of said positions, and means for supplying source gas to said diaphragm-operated means of said transfer valve assembly and said volume stabilizer valve assembly to simultaneously move their valve members to closed positions during the inhalation phase including means for causing a delayed opening of the valve member for the transfer valve assembly at the commencement of the exhalation phase, thereby causing opening of the volume stabilizer valve assembly prior to opening of the volume transfer and exhalation valve assemblies at the end of inhalation so that the gas volume above ambient pressure in the chamber exterior of the bellows will be vented to ambient.
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Accused Products
Abstract
A volume limiting ventilator having a sequencing servo for switching from an inhalation phase to an exhalation phase in its operative cycle. A bellows mounted in a container is provided for receiving gas from a source of gas under pressure. A master venturi is in communication with the interior of the bellows and the exterior of the bellows. A large air breathing tube forming a part of a breathing circuit connects the interior of the bellows to a patient adapter. A master flow cartridge controlled by the sequencing servosupplies source gas to the master venturi. A transfer valve assembly is provided for determining whether the gas flows straight through to the breathing circuit or alternatively is supplied to the container carrying the bellows to raise the bellows. The transfer valve assembly controls the transfer of gas in the container from the exterior of the bellows to the interior of the bellows. A volume stabilizer is provided for stabilizing the volumes between the interior of the bellows and the exterior of the bellows at the termination of the inspiratory phase. An expiratory nebulization cartridge is provided for supplying expiratory nebulization.
53 Citations
21 Claims
- 1. In a volume limiting ventilator having an inhalation phase and an exhalation phase in its operative cycle for use with a source of gas under pressure, an inlet adapted to be connected to the source of gas, a rigid canister, an expandable and collapsible bellows in said canister forming a chamber inside the bellows and in cooperation with the canister forming a chamber exterior of the bellows, a patient adapter adapted to be connected to the airway of the patient, means for connecting the patient adapter to the chamber within the bellows, flow path means for connecting the chamber exterior of the bellows and the chamber inside the bellows, transfer valve means mounted in said flow path means for controlling the flow of gases through the flow path means, a sequencing servo having an inlet connected to the inlet of the ventilator, an outlet, and a valve member movable between open and closed positions for controlling the flow of gases from the inlet to the outlet of the sequencing servo to cause the inhalation phase and the exhalation phase respectively of the ventilator, diaphragm-operated means for moving the valve member between its open and closed positions, means coupled to the sequencing servo for adjusting the forces applied to the diaphragm, a master venturi assembly and a sensing venturi assembly coupled to the flow path means both between the chamber exterior of the bellows and the transfer valve means, means for connecting the sensing servo assembly to the diaphragm-operated means of the sequencing servo so that pressure sensed by the sensing venturi assembly is supplied to the sequencing servo assembly, means connected between the outlet of the sequencing servo assembly and the master venturi assembly for supplying source gas to the master venturi during the inhalation phase, means connected between the inlet of the ventilator and the sensing venturi assembly for supplying source gas to the sensing venturi at the commencement of the exhalation phase, an exhalation valve assembly having an inlet connected to the patient adapter and an outlet vented to the atmosphere, means for supplying source gas from the sequencing servo during the inhalation phase to maintain the exhalation valve assembly in a closed position, a volume stabilizer valve assembly coupled to the master venturi assembly, said transfer valve assembly and said volume stabilizer valve assembly each having a valve member movable between open and closed positions and diaphragm-operated means for moving their valve member toward one of said positions, and means for supplying source gas to said diaphragm-operated means of said transfer valve assembly and said volume stabilizer valve assembly to simultaneously move their valve members to closed positions during the inhalation phase including means for causing a delayed opening of the valve member for the transfer valve assembly at the commencement of the exhalation phase, thereby causing opening of the volume stabilizer valve assembly prior to opening of the volume transfer and exhalation valve assemblies at the end of inhalation so that the gas volume above ambient pressure in the chamber exterior of the bellows will be vented to ambient.
- 13. In a volume limiting ventilator having an inhalation phase and an exhalation phase in its operative cycle for use with a source of gas under pressure, an inlet adapted to be connected to the source of gas, a sequencing servo having an inlet connected to the inlet of the ventilator, an outlet, a valve member movable between open and closed positions for controlling the flow of gases from the inlet to the outlet, and diaphragm-operated means for moving the valve member between open and closed positions, a patient adapter, a master venturi assembly connected to the patient adapter, means connected between the outlet of the sequencing servo and the master venturi for supplying source gases to the master venturi, an exhalation valve assembly having an inlet connected to the patient adapter and an outlet vented to the atmosphere, means for supplying source gas from the sequencing servo to the exhalation valve assembly during the inhalation phase to maintain the exhalation valve assembly in a closed position, an inspiratory nebulization port, nebulizer means adapted to be connected between the nebulization port and the patient adapter, inspiratory nebulizer selector means having an inlet and first and second outlets and valve means for selecting passage of gases from the inlet to either the first outlet or the second outlet, means connecting the first outlet to the inspiratory nebulization port, an entrainment reservoir coupled to the master venturi assembly, means coupling the second outlet to the entrainment reservoir, and means coupling the inlet of the inspiratory nebulizer selector means to the outlet of the sequencing servo whereby a continuous flow of gas is supplied either to the inspiratory nebulization port or alternatively to the entrainment reservoir during the inhalation phase.
- 20. A volume limiting ventilator having an inhalation phase and an exhalation phase in its operative cycle for use with a source of gas under pressure, an inlet adapted to be connected to the source of gas, a rigid canister, expandable and collapsible bellows in said canister forming a chamber inside the bellows and in cooperation with the canister forming a chamber exterior of the bellows, a patient adapter adapted to be connected to the airway of the patient, means for connecting the patient adapter to the chamber within the bellows, flow path means for connecting the chamber exterior of the bellows and the chamber inside the bellows, transfer valve means mounted in said flow path means for controlling the flow of gas through the flow path means, a sequencing serve having an inlet connected to the inlet of the ventilator, an outlet, and a valve member movable between open and closed positions for controlling the flow of gas from the inlet to the outlet, and diaphragm-operated means for moving the valve member between its open and closed positions, a master venturi assembly coupled to said flow path means between the chamber exterior of the bellows and the transfer valve means, means connected between the outlet of the sequencing servo and the master venturi for supplying source gases to the master venturi, means fixed to the container for limiting the travel of the bellows in the container, and means adapted to be operated by the means for limiting the movement of the bellows in the container for controlling the operation of the sequencing servo, said means for limiting the travel of the bellows in the canister including a deck plate forming a portion of said canister and to which deck plate one end of said bellows is fixed, a jack screw rotatably mounted in the deck plate, a volume limiting dial rotatably mounted on the deck plate and adapted to be engaged so that it can be rotated by hand, means for coupling the volume limiting dial to the jack screw so that rotation of the volume limiting dial rotates the jack screw, a volume limiting arm threadably engaging said jack screw so as to be moved toward and away from the deck plate as the jack screw is rotated, and a push rod fixed to the bellows, the push rod and the volume limiting arm having portions adapted for engagement to limit the movement of the bellows away from the base plate at a relative position determined by the position of the volume limiting arm on the jack screw.
Specification