James Paul Froehlich
Engineers in Berlin, PA

5865173, Feb 2, 1999

Nov 6, 1995

8/554595

James P. Froehlich - Berlin PA

Sunrise Medical HHG Inc. - Longmont CO

A61M 1600, A62B 704, F16K 3102, F16K 3126

12820423

A bilevel continuous positive airway pressure (CPAP) respiratory therapy system which applies a prescribed inspiratory positive airway pressure (IPAP) to a patient's respiratory system during inhalation and applies a lower prescribed expiratory positive airway pressure (EPAP) to the respiratory system during exhalation. A blower provides pressurized air at least at the IPAP pressure. A fast response vent valve reduces the pressure applied to the patient to the EPAP level during exhalation and increases the pressure to the set IPAP level during inhalation. Leading edges of pressure changes between the IPAP and EPAP levels are rounded by an adjustable amount to enhance patient comfort and/or to allow the physician to modify the therapy. In an alternate embodiment, the pressure is controlled by controlling the speed of the blower.

5551419, Sep 3, 1996

Dec 15, 1994

8/356471

James P. Froehlich - Berlin PA
Joseph N. Mitchell - Rockwood PA
Stephen M. Jones - Turtle Creek PA

DeVilbiss Health Care, Inc. - Somerset PA

A61M 1600

12820423

The invention relates to continuous positive airway pressure (CPAP) respiratory therapy apparatus for treatment of apnea, hypopnea and other sleep disorders, and particularly to a control for the CPAP apparatus. A blower is connected through a hose and a mask, such as a nasal mask or a nasal cannula, to the patient's respiratory airway. An air flow sensor and an air pressure sensor are located at the blower end of the hose. Optionally, a vent valve also may be located at the blower end of the hose. The sensor outputs are used to estimate the air pressure at the mask and the air flow sensor output is used to determine the gross air flow to the hose, the patient air flow and the occurrence of patient snoring. The air flow sensor output also is used to generate a square wave breathing signal. The breathing signal may be used by a microprocessor to control the optional vent valve to establish different levels in the applied pressure during inspiration and expiration.

5503146, Apr 2, 1996

Oct 26, 1994

8/329641

James P. Froehlich - Berlin PA
Joseph N. Mitchell - Rockwood PA
Stephen M. Jones - Turtle Creek PA

DeVilbiss Health Care, Inc. - Somerset PA

A61M 1600

12820423

The invention relates to continuous positive airway pressure (CPAP) respiratory therapy apparatus for treatment of apnea, hypopnea and other sleep disorders, and particularly to a standby control for automatically operating an air blower in CPAP apparatus. A blower is connected through a hose and a mask, such as a nasal mask or a nasal cannula, to the patient's respiratory airway. Initially, the blower is in a standby mode in which it is either turned off or, preferably, operated at a low speed. When a patient starts breathing through the mask, the blower is automatically switched to an operating mode. In the operating mode, the blower may be controlled to initially supply a low air pressure to the mask which either is increased after a sufficient time delay to allow the patient to fall asleep or is increased in response to the detection of a respiratory event such as apnea or hypopnea. If patient breathing through the mask ceases because the mask has been removed or otherwise is no longer sufficiently sealed to the patient's airway, the blower is automatically returned to the low pressure standby mode. If the patient does not begin breathing through the mask within a predetermined time, the blower is stopped.