Positive expiratory pressure devices with flutter valve

Abstract

A positive pressure airway device for providing resistance in an air pathway for a patient exhaling. The device includes a central tube region, a inspiratory air passageway for passing air into the central tube region when a patient breathing through the device inhales, and an expiratory air passageway for passing air out of the central tube region when a patient breathing through the device exhales, A valve in the expiratory air passageway allows air to flow out only when a patient using the device exhales with an expiratory air pressure greater than a selected pressure, and includes a stopper and a coil spring with an interior portion that is free from any structure that would inhibit the “side-to-side” movement of the spring within the housing. The stopper has a cone-shaped air-stopping surface providing a valve angle that is different from the valve-seat angle so that either laminar or oscillating flow may be obtained.

1 . A device for providing resistance in an air pathway for a patient who is exhaling, the device comprising:
 a) a central tube region;   b) a first passageway for passing air into the central tube region when the patient breathing through the device inhales;   c) a second passageway for passing air out of the central tube region when the patient breathing through the device exhales, wherein the second passageway has an upper portion defined by an upper wall, a lower portion defined by a lower wall, and a transitional wall connecting the lower wall to the upper wall, and wherein the transitional wall is slanted at an angle α with respect to a line perpendicular to the vertical axis of the second passageway, thus providing a passageway having a valve seat angle α;   d) a third passageway for passing air from the central tube region and into the patient when the patient breathing through the device inhales, and for passing air from the patient to the central tube when the patient breathing through the device exhales;   e) a valve in the first passageway that allows air to flow in through the first passageway to the central tube when the patient using the device inhales, and that prevents air from flowing out through the first passageway when the patient using the device exhales;   f) a valve in the second passageway that allows air to flow out from the second passageway when the patient using the device exhales with an expiratory air pressure greater than a selected pressure, that prevents air from flowing out through the second passageway when the patient exhales with an expiratory air pressure that is less than said selected pressure, and that prevents air from flowing in through the second passageway when the patient using the device inhales, wherein the valve in said second passageway includes:
 i) a stopper to close the second passageway and to prevent air from flowing through the second passageway when the stopper is biased to a closed position, and 
 ii) a stopper-biasing spring to maintain the stopper in its closed position unless the expiratory air pressure in the second passageway is greater than the selected pressure, wherein the stopper-biasing spring is a coil spring having a stopper end connected to the stopper, a cap end opposite the stopper, and an interior; and 
   g) a spring housing cap connected to the cap end of the stopper-biasing spring and effective to retain the stopper-biasing spring and to partially compress the spring to a length shorter than its free length, wherein the spring housing cap is movable with respect to the transitional wall of the second passageway so that movement of the spring housing cap is effective for varying the compression length of the spring, and thus is effective for varying the expiratory air pressure that will cause the valve of the second passageway to open, and wherein the stopper-biasing spring is attached at its first end to the spring housing cap, and at its second end to the stopper, with the spring interior being free from any structure that would significantly inhibit “side-to-side” movement of the spring within the second passageway and would accordingly prevent the device from providing an oscillating flow of air to the patient.