Reusable airflow sensor

• US 20050096560A1
• Filed: 11/04/2003
• Published: 05/05/2005
• Est. Priority Date: 11/04/2003
• Status: Abandoned Application

• Current Assignee: Dymedix Corporation
• Original Assignee: Dymedix Corporation
• Inventors: Ham, William H., Alfini, Susan S.
• Application Number:
  US10/702,623
• Publication Number:
  US 20050096560A1
• Time in Patent Office: Days
• US Class Current: 600/538
• CPC Class Codes: A61B 5/0803 Recording apparatus specially adapted therefor
• CPC Class Codes: A61B 5/0878 using temperature sensing means
• CPC Class Codes: A61B 5/4806 Sleep evaluation A61B5/4821 takes precedence; devices for inducing sleep A61M21/02
• CPC Class Codes: B29C 39/10 incorporating preformed parts or layers, e.g. casting around inserts or for coating articles coating a surface by casting in general B05D1/30, B29C39/126 takes precedence
• CPC Class Codes: B29C 39/123 Making multilayered articles
• CPC Class Codes: B29C 70/72 Encapsulating inserts having non-encapsulated projections, e.g. extremities or terminal portions of electrical components B29C70/742 takes precedence
• CPC Class Codes: B29L 2031/752 Measuring equipment
• CPC Class Codes: B29L 2031/753 Medical equipment; Accessories therefor bloodbags, medical bags B29L2031/7148; artificial eyes B29L2011/0008

Abstract

A reusable airflow sensor for monitoring respiratory activity of patients in a sleep lab setting comprises a polyvinylidne fluoride (PVDF) film totally encased within a thermally conductive plastic material that is non-hydroscopic and therefore impervious to moisture which allows resterilization without comprising the electrical performance of the sensor.

Claims

1. A method of making a reusable airflow sensor comprising the steps of:

(a) providing a mold with a mold cavity of a predetermined shape configuration;

(b) providing a polyvinylidene fluoride film of a size to fit within said cavity, said film including a conductive material adhered to opposed major surfaces of said film;

(c) affixing conductive leads to the conductive material on the opposed major surfaces;

(d) inserting said film into said cavity with said leads extending beyond the cavity;

(e) injecting a non-hydroscopic plastic into said mold to fill the cavity and encapsulate said film; and

(f) removing the product of step (e) from the mold following solidification of the plastic.

2. The method of claim 1 wherein the plastic is thermally conductive.

3. The method of claim 1 wherein the plastic is such that the product of step (f) is repeatedly sterilizable.

4. The method of either claim 1 or claim 2 wherein the plastic exhibits a resistivity of at least 10¹⁰ ohm-cm.

5. The method as in claim 1 wherein a height dimension of the mold cavity is in a range from about 0.24 mm to 5 mm.

6. A reusable airflow sensor comprising:

(a) a film of polyvinylidene fluoride material having opposed major surfaces, the opposed major surfaces having a layer of metalization thereon with a pair of elongated conductive leads, each having one end thereof individually affixed to the metalization layers on the opposed major surfaces; and

(b) a sterilizable, medical-grade, non-hydroscopic plastic totally encapsulating said film, metalization layers and said at least one ends of said pair of leads.

7. The reusable airflow sensor as in claim 6 wherein said film, said layers of metalization and said at least one ends of said pair of leads are hermetically sealed within said plastic.

8. The reusable airflow sensor as in either claim 6 or claim 7 wherein the plastic is selected from a group consisting of polyamide 4,6, polyvinyl chloride, polyethylene, polystyrene, thermally conductive acrylonitrile butadiene styrene, thermally conductive polyphenylene sulfide, and thermally conductive silicone vulcanite.

9. The reusable airflow sensor of claim 7 wherein the plastic encapsulating said film, said layers of metalization and said at least one ends allows the airflow sensor to be flexible.

10. The reusable airflow sensor as in claim 6 wherein the plastic has a high resistivity in a range from about 10¹⁰ to 10¹⁵ ohm-cm.

11. The reusable airflow sensor as in claim 6 wherein the plastic is selected from the group consisting of acrylonitrile butadiene styrene, polyphenylene sulfide, silicone vulcanite and polyamide 4,6.

12. The reusable airflow sensor as in claim 6 wherein the thermal conductivity of said plastic is in a range from about 1.0 W/mk to 20 W/mk.