Flexible PTC heating element and method of manufacturing the heating element

• US 7,049,559 B2
• Filed: 06/16/2003
• Issued: 05/23/2006
• Est. Priority Date: 06/19/2002
• Status: Expired due to Term

• Current Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Terakado, Seishi, Yoneyama, Mitsuru, Yasui, Keiko, Ishii, Takahito, Kohara, Kazuyuki
• Primary Examiner(s): Evans, Robin O.
• Assistant Examiner(s): PATEL, VINOD D
• Application Number:
  US10/517,188
• Publication Number:
  US 20050173414A1
• Time in Patent Office: 1,072 Days
• Field of Search: 219/549, 219/505, 219/529, 219542-546, 219/548, 338210-211, 338306-309, 338/314
• US Class Current: 219/549
• CPC Class Codes: B60H 1/2227 Electric heaters incorporated in vehicle trim components, e.g. panels or linings
• CPC Class Codes: H01C 1/01 Mounting; Supporting
• CPC Class Codes: H01C 1/012 the base extending along and imparting rigidity or reinforcement to the resistive element H01C1/016 takes precedence; the resistive element being formed in two or more coils or loops as a spiral, helical or toroidal winding H01C3/18, H01C3/20; the resistive element being formed as one or more layers or coatings on a base H01C7/00
• CPC Class Codes: H01C 1/1406 Terminals or electrodes formed on resistive elements having positive temperature coefficient
• CPC Class Codes: H01C 17/065 by thick film techniques, e.g. serigraphy
• CPC Class Codes: H01C 17/06586 composed of organic material
• CPC Class Codes: H01C 7/02 having positive temperature coefficient ceramics C04B
• CPC Class Codes: H01C 7/027 consisting of conducting or semi-conducting material dispersed in a non-conductive organic material
• CPC Class Codes: H05B 2203/006 using interdigitated electrodes
• CPC Class Codes: H05B 2203/013 Heaters using resistive films or coatings
• CPC Class Codes: H05B 2203/017 Manufacturing methods or apparatus for heaters
• CPC Class Codes: H05B 2203/02 Heaters using heating elements having a positive temperature coefficient
• CPC Class Codes: H05B 2203/029 Heaters specially adapted for seat warmers
• CPC Class Codes: H05B 3/342 heaters used in textiles

Abstract

The flexible PTC heating element according to the invention has one of the following constitutions. A portion of an electrodes and a PTC resistor is impregnated into a flexible substrate. A flexible substrate is made of resin foam or rubber material having a concave/convex shape formed on the surface. The flexible PTC heating element has an elongation deformation portion disposed to at least one of an electrode and a PTC resistor. A flexible substrate has adhesiveness and either a flexible substrate or a flexible cover material has an elongation control portion. Therefore, the flexible PTC heating element is highly flexible and excellent in vibration durability.

Claims

1. A flexible PTC heating element comprising:

a flexible fibrous material having a surface;

first and second conductive materials disposed on at least a part of the surface of the fibrous material in a pattern in which the first and second conductive materials at least partially overlap each other, wherein one of the first and second conductive materials has a PTC property, and at least one of the first and second conductive materials contains a flexible binder which enables the at least one conductive material to flex with the fibrous material; and

a control material provided on at least a part of the surface of the fibrous material to control impregnation of the first and second conductive materials into the fibrous material;

wherein the first and second conductive materials are configured to receive electric current to heat the conductive material which has the PTC property.

2. A flexible PTC heating element according to claim 1, wherein the control material forms a control layer on the surface of the fibrous material, and the first and second conductive materials are printed on the control layer.

3. A flexible PTC heating element according to claim 1, wherein the control material comprises one or more materials selected from the group consisting of urethane thermoplastic elastomer, olefin thermoplastic elastomer and styrene thermoplastic elastomer.

4. A flexible PTC heating element according to claim 1, wherein the control material further comprises an adhesive resin and an elastomer material.

5. A flexible PTC heating element according to claim 1, wherein the fibrous material is non-woven fabric.

6. A flexible PTC heating element according to claim 1, wherein the flexible binder comprises an elastomer material.

7. A flexible PTC heating element according to claim 1, both first and second conductive materials comprise the flexible binder.

8. A flexible PTC heating element according to claim 1, further comprising at least one hole formed through the fibrous material.