Manual resuscitators with integral manometer

1. A manual resuscitator apparatus comprising:

a housing having an inlet and outlet connected by a communication path to permit air flow through the communication path;

a pressure gauge forming part of the housing having a sensing chamber in communication with the communication path and an atmospheric chamber in communication with ambient atmosphere, the chambers being separated by a diaphragm subject to distortion from a rest position upon a differential pressure between the chambers, with a spring associated with said diaphragm to restore said diaphragm to a rest position upon equalization of the pressures in the chambers;

a first bearing attached to said diaphragm and a second bearing in one of said chambers;

a shaft journaled in said bearings for rotation in one direction upon diaphragm distortion and rotation in another direction by diaphragm restoration; and

an indicator associated with said shaft to indicate differences in pressure between the sensing and atmospheric chambers causing diaphragm distortion.

2. An apparatus as claimed in claim 1 wherein the sensing chamber is below the atmospheric chamber, and the indicator is in the atmospheric chamber.

3. An apparatus as claimed in claim 1 wherein the indicator is in the atmospheric chamber.

4. An apparatus as claimed in claim 1 wherein the atmospheric chamber includes a transparent it window, the indicator is in the atmospheric chamber and includes a dial in the atmospheric chamber visible through the window and a pointer on the shaft.

5. An apparatus as claimed in claim 1 wherein the housing and the pressure gauge are formed of plastic ultrasonically welded together.

6. An apparatus as claimed in claim 1 wherein the pressure gauge includes a check valve and a lower housing part extending toward the check valve and having circumferentially arranged crescent-shaped openings to establish communication between the sensing chamber and the communication path.

7. An apparatus as claimed in claim 1 wherein the pressure gauge includes a lower housing part and having circumferentially arranged crescent-shaped openings in the lower housing part to establish communication between the sensing chamber and the communication path.

8. An apparatus as claimed in claim 1 wherein the atmospheric chamber encloses the spring and the second bearing.

9. An apparatus as claimed in claim 1 wherein the sensing chamber includes a sleeve aligned with the first bearing and positioned to receive the shaft when the diaphragm is distorted by a pressure differential.

10. An apparatus as claimed in claim 1 wherein the first bearing has an aperture with an outward notch and the shaft has a helical thread adapted to ride in the notch and rotate the shaft as the first bearing moves with diaphragm distortion.

11. An apparatus as claimed in claim 1 wherein the pressure gauge includes a check valve and a lower housing part extending toward the check valve and the sensing chamber includes a first sleeve aligned with the first bearing for receiving the shaft when the diaphragm is distorted by a pressure differential and a second sleeve on the lower housing part to maintain alignment of the first sleeve.

12. An apparatus as claimed in claim 1 wherein the pressure gauge includes a lower housing part and the sensing chamber includes a first sleeve aligned with the first bearing for receiving the shaft when the diaphragm is distorted by a pressure differential and a second sleeve on the lower housing part to maintain alignment of the first sleeve.

13. A manual resuscitator apparatus comprising:

a housing having an inlet and outlet connected by a communication path and a check valve to permit air flow through the communication path from the outlet to the inlet;

a pressure gauge and the housing made of plastic ultrasonically welded together, the pressure gauge having a sensing chamber bounded by a lower housing part extending toward the check valve, the lower housing part having circumferentially arranged crescent-shaped openings to establish communication between the sensing chamber and the communication path,

an atmospheric chamber in communication with ambient atmosphere and having a transparent window and a dial visible through the transparent window, with the sensing chamber positioned between the atmospheric chamber and the communication path, the chambers being separated by a diaphragm subject to distortion from a rest position upon a differential pressure between the chambers, with a spring in the atmospheric chamber associated with the diaphragm to restore the diaphragm to the rest position upon equalization of the pressures in the chambers;

a first bearing attached to the diaphragm and a second bearing in the atmospheric chamber;

a shaft journaled in the bearings for rotation in one direction upon diaphragm distortion and rotation in another direction by diaphragm restoration;

the sensing chamber including a first sleeve aligned with a first bearing for receiving the shaft when the diaphragm is distorted by a pressure differential and a second sleeve on the lower housing part to maintain alignment of the first sleeve, and

a pointer on the shaft in the atmospheric chamber visible with the dial through the transparent window to indicate differences in pressure between the sensing and atmospheric chambers causing diaphragm distortion.

14. A manual resuscitator apparatus comprising:

a housing having all inlet and outlet connected by a communication path to permit air flow through the communication path;

a pressure gauge and the housing made of plastic ultrasonically welded together, the pressure gauge having a sensing chamber bounded by a lower housing part, the lower housing part having circumferentially arranged crescent-shaped openings to establish communication between the sensing chamber and the communication path,

an atmospheric chamber in communication with ambient atmosphere and having a transparent window and a dial visible through the transparent window, with the sensing chamber positioned between the atmospheric chamber and the communication path, the chambers being separated by a diaphragm subject to distortion from a rest position upon a differential pressure between the chambers, with a spring in the atmospheric chamber associated with the diaphragm to restore the diaphragm to the rest position upon equalization of the pressures in the chambers;

a first bearing attached to the diaphragm and a second bearing in the atmospheric chamber;

a shift journaled in the bearings for rotation in one direction upon diaphragm distortion and rotatior in another direction by diaphragm restoration;

the sensing chamber including a first sleeve aligned with a first bearing for receiving the shaft when the diaphragm is distorted by a pressure differential and a second sleeve on the lower housing part to maintain alignment of the first sleeve, and

a pointer on the shaft in the atmospheric chamber visible with the dial through the transparent window to indicate differences in pressure between the sensing and atmospheric chambers causing diaphragm distortion.

15. A method of providing respiratory assistance to a patient comprising

supplying air to the patient through a housing having an inlet and outlet connected by a communication path; and

displaying the pressure of supplied air in the housing on a pressure gauge integrally mounted to the housing by distorting a diaphragm from a rest position upon a differential pressure between two chambers in the housing and restoring the diaphragm to the rest position upon equalization of the pressures in the chambers, thereby moving an indicator coupled to the diaphragm to indicate differences in pressure between the chambers.

16. A method as claimed in claim 15 further comprising viewing the indicator and a dial in the gauge through the window.

17. A method as claimed in claim 15 further comprising the preliminary step of ultrasonically welding the housing and pressure gauge together.