Flow detector
AssigneeBourns Medical Systems, Inc.
InventorsReno L. Vicenzi, Paul R. Smargiassi
Life of this patent
Estimating the term…
Abstract
A flow detector including an orifice for forming a vena contracta to activate a connected pressure detector so as to trigger an alarm mechanism upon the occurrence of disconnect of the patient exhalation valve in a mechanical ventilator system. A configuration of the flow detector makes erroneous hookup of the ventilator and pressure detector hoses all but impossible.
Claims8
In a system for actuating an exhalation valve for use in respiratory therapy comprised of a source of pressurized gas, a gas pressure actuated valve closure member, a valve seat for the valve member, means connecting the pressurized gas source to the valve closure member and a detector coupled to the connecting means for detecting leaks, the improvement comprising the use of an improved flow detector coupled inline between upstream and downstream portions of the connecting means for providing an output signal when there is insufficient pressure to force the gas pressure actuated valve closure member against its valve seat during the inspiration portion of a breathing cycle, said improved flow detector including:
- a chamber coupled to the connecting means, said chamber being normally pressurized by gas from the gas source at a pressure substantially determined by the gas source;
- first low pressure generating means coupled inline between said upstream and downstream portions of the connecting means and located immediately upstream of said chamber, said low pressure generating means being responsive to the flow of gas therethrough from the pressurized gas source due to a leak or disconnect in said downstream portion of the connecting means for causing the pressure in said chamber to decrease below a predetermined value;
- and
- pressure sensing means coupled to said chamber for providing a predetermined output signal when the pressure in said chamber decreases below the predetermined value.
A flow detector for use in detecting leaks and disconnects in a system for pressuring a pressure activated exhalation valve closure member by pressurized gas from a gas pressure source, said flow detector comprising:
- an input passageway for receiving pressurized gas from the gas pressure source;
- orifice means coupled to said input passageway;
- an output passageway coupled between said orifice means and the pressure activated exhalation valve closure member, for providing a path for the pressurized gas between said orifice means and the exhalation valve closure member, said output passageway including chamber means located immediately downstream from said orifice means said chamber means being normally pressurized by gas from the gas pressure source at a pressure substantially determined by the gas pressure source, said orifice means being responsive to the flow of gas therethrough due to a leak or disconnect in the system between said chamber means and the pressure activated exhalation valve closure member for causing the pressure in said chamber means to decrease below a predetermined value;
- and
- sensor means, connected to said chamber means, for sensing the gas pressure within said chamber means and providing a predetermined output signal when the pressure in said chamber means is below the predetermined value.
Dependencies are inferred from the claim text.