Flow sensor system

• US 5,558,099 A
• Filed: 07/06/1995
• Issued: 09/24/1996
• Est. Priority Date: 03/05/1991
• Status: Expired due to Term

• Current Assignee: Embla Systems, Inc. (Natus Medical Incorporated)
• Original Assignee: EdenTec Corporation (Medtronic Plc)
• Inventors: Bowman, Bruce, Stasz, Peter
• Primary Examiner(s): Kamm, William E.
• Assistant Examiner(s): Jastrzab, Jeffrey R.
• Application Number:
  US08/498,580
• Time in Patent Office: 446 Days
• Field of Search: 128/716, 128/724, 128/725, 128/639, 128/640, 128/671, 128/736, 374/178, 374/183, 374/185, 338/22 R, 338/211, 338/308
• US Class Current: 600/538
• CPC Class Codes: A61B 5/0878 using temperature sensing means
• CPC Class Codes: G01F 1/684 Structural arrangements; Mounting of elements, e.g. in relation to fluid flow
• CPC Class Codes: G01F 1/692 Thin-film arrangements
• CPC Class Codes: Y10T 29/49085 Thermally variable
• CPC Class Codes: Y10T 29/49099 Coating resistive material on a base

Abstract

A plurality of flow sensors are fabricated on a single substrate. The substrate is laid out to provide the proper physical relationship of the individual sensors. The resulting multiple sensor structure may be effectively used as respiration detector by positioning a different sensor element at each of the airflow orifices (i.e., two nostrils and mouth) of a patient. In the preferred embodiment, the sensors are thermoresistive elements, which are screened on the substrate using conductive ink. The change in temperature of the air flow in relation to the ambient at each orifice provides an indication of the flow and may be used to determine the extent of the flow. The substrate is packaged in a single piece adhesive strip which provides ease of proper attachment by the patient.

Claims

1. An apparatus comprising:

a flexible substrate;

at least one heat sensor attached to the flexible substrate;

a connector, wherein the connector comprises a region of conductive ink attached to the flexible substrate; and

a conductive path of conductive ink attached to the flexible substrate electrically coupling the at least one heat sensor to the connector.

2. An apparatus according to claim 1, wherein the conductive path and the connector comprise the same compound.

3. An apparatus in accordance with claim 1, wherein the conductive path and the connector comprise different compounds.

4. An apparatus in accordance with claim 1, wherein the at least one heat sensor is fixedly attached to said flexible substrate at an incline with respect to the plane of the flexible substrate.

5. An apparatus in accordance with claim 1, wherein the at least one heat sensor is attached to the flexible substrate at a position adapted to intersect a first air passage of a patient.

6. An apparatus in accordance with claim 5 wherein the at least one heat sensor is attached to the flexible substrate in a position adapted to intersect a second air passage of the patient.

7. An apparatus comprising:

a. a substrate;

b. a heat sensor fixedly attached to said substrate at an angle relative to the plane of said substrate; and

c. a conductive path fixedly attached to said substrate electrically coupled to said heat sensor.

8. An apparatus according to claim 7 wherein said conductive path comprises conductive ink.

9. An apparatus according to claim 8 further comprising a connector fixedly attached to said substrate and electrically coupled to said conductive path.