Portable ventilator apparatus

• US 4,941,469 A
• Filed: 05/23/1988
• Issued: 07/17/1990
• Est. Priority Date: 11/12/1987
• Status: Expired due to Term

• Current Assignee: Carmeli Adahan
• Original Assignee: Carmeli Adahan
• Inventors: Adahan, Carmeli
• Primary Examiner(s): Burr, Edgar S.
• Assistant Examiner(s): Asher, Kimberly L.
• Application Number:
  US07/197,198
• Time in Patent Office: 785 Days
• Field of Search: 128/204.21, 128/205.18, 128/204.18, 128/205.11, 128/205.19, 128/204.26, 128/203.12, 128/203.16, 128/205.24, 417/542
• US Class Current: 128/205.18
• CPC Class Codes: A61M 16/00 Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes stimulating the respiratory movement by mechanical, pneumatic or electrical means, iron lungs combined with gas breathing means A61H31/00
• CPC Class Codes: A61M 16/0009 with sub-atmospheric pressure, e.g. during expiration
• CPC Class Codes: A61M 16/0069 the speed thereof being controlled by respiratory parameters, e.g. by inhalation
• CPC Class Codes: A61M 16/022 Control means therefor
• CPC Class Codes: A61M 16/0833 T- or Y-type connectors, e.g. Y-piece
• CPC Class Codes: A61M 16/107 in the inspiratory path
• CPC Class Codes: A61M 16/1075 by influencing the temperature A61M16/1045 takes precedence
• CPC Class Codes: A61M 16/109 the humidifying liquid or the beneficial agent
• CPC Class Codes: A61M 16/16 Devices to humidify the respiration air A61M16/1045 takes precedence

Abstract

Ventilator apparatus comprises a cyclically-operated reciprocating pump, a delivery tube for delivering pressurized air to a patient, an exhalation valve assembly producing breathing cycles in which the delivery tube is first connected to the patient to effect inhalation and then is vented to the atmosphere to permit exhalation, and a control valve operated by the pump for controlling the breathing cycles of the exhalation valve. The pump has a low volume-displacement and operates at a relatively high cyclical speed, thereby enabling the apparatus to be selectively operated to perform the functions of any one of a large number of different types of ventilators.

Claims

1. Ventilator apparatus comprising:

a pump including a negative-pressure chamber having an inlet for drawing air into the chamber, and a positive-pressure chamber having an outlet for outletting pressurized air;

delivery means for delivering pressurized air to a patient;

an exhalation valve assembly producing breathing cycles in which the delivery means is first connected to the patient to effect inhalation, and then is vented to the atmosphere to permit exhalation; and

a control valve operated by said pump for controlling the breathing cycles of the exhalation valve;

characterized in that said pump is a cyclically-operated reciprocating pump and has a low volume displacement in the order of the displacement produced by a piston-type pump having a piston diameter of less than 40 mm, operates at a cyclical speed to effect at least 2 cycles of operation for each breathing cycle of the exhalation valve, and includes an expansible member in the flow path of the air from the positive pressure chamber to the delivery means to damp oscillations produced by the reciprocating pump.

2. The apparatus according to claim 1, wherein said pump includes two pistons reciprocated within a cylinder, each of said pistons having a diameter of less than 40 mm.

3. The apparatus to claim 1, further including an air inlet into said negative-pressure chamber, an oxygen inlet into said negative-pressure chamber, and proportioning means controlling the proportion of the air and oxygen inletted via their respective inlets.

4. The apparatus according to claim 3, wherein said pump comprises a pair of pistons reciprocatable in opposite ends of a cylinder;

said proportioning means comprises air and oxygen orifices formed in opposite ends of said cylinder each adjacent one of the pistons, and an ajustable mounting for said cylinder with respect to said pistons such that adjusting the cylinder in one direction causes the air orifice to be uncovered a greater part of the reciprocatory cycle thereby increasing the proportion of air in the delivered gas, and adjusting the cylinder in the opposite direction causes the oxygen orifice to be uncovered a greater part of the reciprocatory cycle thereby increasing the proportion of oxygen in the delivered gas.

5. The apparatus according to claim 4, wherein said cylinder is adjustable by a pinion and rack mechanism.

6. The apparatus according to claim 1, further including a relief valve communicating with said delivery means for preventing the pressure in the delivery means from rising above a predetermined peak;

a sensor for sensing the pressure in said delivery means; and

control means effective to energize said pump when the sensed pressure in the delivery means is below said peak value, and to deenergize the pump when the sensed pressure is substantially equal to said peak value.

7. The apparatus according to claim 6, wherein said control means comprises a storage device for storing the peak pressure sensed by said sensor, and a comparator for continuously comparing the sensed pressure with the stored peak pressure and effective to energize the pump whenever the sensed pressure in the delivery means is below said stored peak value, and to deenergize the pump whenever the sensed pressure is substantially equal to said stored peak value.

8. The apparatus according to claim 7, wherein said pressure sensor produces an electrical output corresponding to the pressure sensed by the sensor, said storage means being an electrical device storing the peak pressure sensed by the sensor, said comparator being an electrical comparator circuit for comparing the sensed pressure with the peak pressure stored in said storage device.

9. The apparatus according to claim 6, wherein said control means is effective to energize said pump when the sensed pressure in the delivery means is 5-10% below said peak pressure.

10. The apparatus according to claim 1, wherein said pump is operated at a speed of 20 to 30 cycles per breathing cycle.

11. Ventilator apparatus comprising:

a reciprocating pump including a negative-pressure chamber having an inlet for drawing air into the chamber, and a positive-pressure chamber having an outlet for outletting pressurized air;

delivery means for delivering pressurized air to a patient;

an exhalation valve assembly producing breathing cycles in which the delivery means is first connected to the patient to effect inhalation, and then is vented to the atmosphere to permit exhalation;

control means for operating said pump at a speed to effect at least two cycles of operation for each breathing cycle of the exhalation valve; and

a control valve operated by said pump for controlling the breathing cycles of the exhalation valve;

said pump including an expansible bellows in the flow path of the air from the positive-pressure chamber to the delivery means to damp oscillations in pressure produced by the reciprocating pump.

12. The apparatus according to claim 11, wherein said pump has a low volume-displacement in the order of the displacement produced by a piston-type pump having a piston diameter of less than 40 mm and said control means operates the pump at 20-30 cycles of operation for each breathing cycle of the exhalation valve.

13. The apparatus according to claim 12, wherein said pump includes two pistons reciprocated within a cylinder, each of said pistons having a diameter of less than 40 mm.

14. The apparatus according to claim 11, further including an air inlet into said negative-pressure chamber, an oxygen inlet into said negative-pressure chamber, and proportioning means controlling the proportion of the air and oxygen inletted via their respective inlets.

15. The apparatus according to claim 14, wherein said pump comprises a pair of pistons reciprocatable in opposite ends of a cylinder;

said proportioning means comprising air and oxygen orifices formed in opposite ends of said cylinder each adjacent one of the pistons, and an ajustable mounting for said cylinder with respect to said pistons such that adjusting the cylinder in one direction causes the air orifice to be uncovered a greater part of the reciprocatory cycle thereby increasing the proportion of air in the delivered gas, and adjusting the cylinder in the opposite direction causes the oxygen orifice to be uncovered a greater part of the reciprocatory cycle thereby increasing the proportion of oxygen in the delivered gas.

16. The apparatus according to claim 11, further including a relief valve communicating with said delivery means for preventing the pressure in the delivery means from rising above a predetermined peak;

a sensor for sensing the pressure in said delivery means; and

control means effective to energize said pump when the sensed pressure in the delivery means is below said peak value, and to deenergize the pump when the sensed pressure is substantially equal to said peak value.

17. Ventilator apparatus comprising:

a cyclically-operated reciprocating pump including a negative-pressure chamber having an inlet for drawing air into the chamber, and a positive-pressure chamber having an outlet for outletting pressurized air;

delivery means for delivering pressurized air to a patient;

an exhalation valve assembly producing breathing cycles in which the delivery means is first connected to the patient to effect inhalation, and then is vented to the atmosphere to permit exhalation;

a control valve operated by said pump for controlling the breathing cycles of the exhalation valve;

control means for operating said pump at a speed to effect at least two cycles of operation for each breathing cycle of the exhalation valve;

an air inlet into said negative-pressure chamber;

an oxygen inlet into said negative-pressure chamber; and

proportioning means controlling the proportion of the air and oxygen inletted via their respective inlets.

18. The apparatus according to claim 17, wherein said pump comprises a pair of pistons reciprocatable in opposite ends of a cylinder;

said proportioning means comprising air and oxygen orifices formed in opposite ends of said cylinder each adjacent one of the pistons, and an ajustable mounting for said cylinder with respect to said pistons such that adjusting the cylinder in one direction causes the air orifice to be uncovered a greater part of the reciprocatory cycle thereby increasing the proportion of air in the delivered gas, and adjusting the cylinder in the opposite direction causes the oxygen orifice to be uncovered a greater part of the reciprocatory cycle thereby increasing the proportion of oxygen in the delivered gas.

19. The apparatus according to claim 17, further including a relief valve communicating with said delivery mans for preventing the pressure in the delivery means from rising above a predetermined peak;

a sensor for sensing the pressure in said delivery means; and

control means effective to energize said pump when the sensed pressure in the delivery means is below said peak value, and to deenergize the pump when the sensed pressure is substantially equal to said peak value.

20. The apparatus according to claim 17, wherein said pump includes an expansible member in the flow path of the air from the positive pressure chamber to the delivery means to damp oscillations produced by the reciprocating pump.