AIR FLOW RATE SENSOR

• US 20110270541A1
• Filed: 04/21/2011
• Published: 11/03/2011
• Est. Priority Date: 04/29/2010
• Status: Abandoned Application

• Current Assignee: Chan G.I. Kim, Eun Jong Cha, In Kwang Lee, Kyung A.H. Kim
• Original Assignee: Chan G.I. Kim, Eun Jong Cha, In Kwang Lee, Kyung A.H. Kim
• Inventors: Cha, Eun Jong, Kim, Kyung Ah, Lee, In Kwang, Kim, Chan Gi
• Application Number:
  US13/091,391
• Publication Number:
  US 20110270541A1
• Time in Patent Office: Days
• US Class Current: 702/47
• CPC Class Codes: A61B 5/087 Measuring breath flow
• CPC Class Codes: A61B 5/0873 using optical means
• CPC Class Codes: A61B 5/0876 using means deflected by the fluid stream, e.g. flaps
• CPC Class Codes: A61B 5/0878 using temperature sensing means
• CPC Class Codes: A61B 5/09 using an element rotated by the flow toys actuated by air current A63H33/40
• CPC Class Codes: A61B 8/00 Diagnosis using ultrasonic, sonic or infrasonic waves imaging of objects using sonar G01S15/00
• CPC Class Codes: A61M 16/021 operated by electrical means A61M16/202 – A61M16/205 take precedence
• CPC Class Codes: A61M 2016/003 with a flowmeter
• CPC Class Codes: A61M 2016/0039 in the inspiratory circuit
• CPC Class Codes: A61M 2016/0042 in the expiratory circuit
• CPC Class Codes: G01F 1/34 by measuring pressure or differential pressure
• CPC Class Codes: G01F 1/36 the pressure or differential pressure being created by the use of flow constriction
• CPC Class Codes: G01F 1/40 Details of construction of the flow constriction devices

Abstract

Disclosed is an air flow rate sensor capable of sensing an air flow rate and respirator air flow rate. The air flow rate sensor includes a chamber having left and right portions having same internal diameters and a central portion having an internal diameter greater than the internal diameters of the left and right portions, first and second pressure taps provided at the left and right portions of the chamber, respectively, and a pressure sensor connected to the first and second pressure taps to measure a differential pressure between the left and right portions of the chamber. There are obstacles on the path of air flow, so that exact and uniform measurement characteristics are maintained. Since energy loss is measured by using vortex, the structure of the air flow rate sensor is simplified. The air flow rate sensor is used as a respirator air flow rate sensor.

Claims

1. An air flow rate sensor comprising:

a chamber having left and right portions having same internal diameters and a central portion having an internal diameter greater than the internal diameters of the left and right portions;

first and second pressure taps provided at the left and right portions of the chamber, respectively; and

a pressure sensor connected to the first and second pressure taps to measure a differential pressure between the left and right portions of the chamber.

2. The air flow rate sensor of claim 1, wherein the chamber has a hollow form.

3. The air flow rate sensor of claim 1, wherein the central portion of the chamber has the internal diameter three times greater than the internal diameters of the left and right portions.

4. The air flow rate sensor of claim 1, wherein the left and right portions of the chamber have external diameters different from each other.

5. The air flow rate sensor of claim 4, wherein the external diameters of the left and right portions of the chamber have a size sufficient to connect the chamber between an endo-tracheal tube and an ambu-bag which are standardized CPR equipments.

6. The air flow rate sensor of claim 1, wherein the pressure sensor calculates the differential pressure between the left and right portions of the chamber by a polynomial function of air flow, in which the polynomial function is expressed as P_diff=P₁−

P₂=f(F)=a₁F+a₂F²+a₃F³+ . . . =a₁F+a₂F².

7. The air flow rate sensor of claim 6, wherein P₁,P₂ represent pressures at the left and right portions of the chamber, P_diff represents a differential pressure between the left and second portions of the chamber measured by the pressure sensor through the first and second pressure taps, and the F represents an air flow rate, and a₁,a₂,a₃, . . . represent constants.

8. The air flow rate sensor of claim 1, wherein the chamber includes a disposable chamber including transparent acrylic material such that the chamber is easily replaced with a new chamber.