ELECTRICAL HEATERS

• US 3,594,547 A
• Filed: 12/17/1968
• Issued: 07/20/1971
• Est. Priority Date: 12/23/1967
• Status: Expired due to Term

• Current Assignee: Quinn Joseph Thomas
• Original Assignee: Quinn Joseph Thomas
• Inventors: QUINN JOSEPH THOMAS
• Application Number:
  US04/784,431
• Time in Patent Office: 945 Days
• US Class Current: 219/529
• CPC Class Codes: B60S 1/586 including defroster or demisting means
• CPC Class Codes: H05B 1/0225 actuated by timers
• CPC Class Codes: H05B 2203/005 using multiple resistive elements or resistive zones isolated from each other
• CPC Class Codes: H05B 2203/011 Heaters using laterally extending conductive material as connecting means
• 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 2203/029 Heaters specially adapted for seat warmers
• CPC Class Codes: H05B 2203/033 Heater including particular mechanical reinforcing means
• CPC Class Codes: H05B 3/26 heating conductor mounted on insulating base for transparent areas H05B3/84, H05B3/86
• CPC Class Codes: H05B 3/342 heaters used in textiles

Abstract

An electrical heater for use in heating the engine, battery, seat or rear window of an automobile includes a thin, flexible rectangular heating pad embodying a composite electrical resistance sheet, a time switch mounted on the pad at a corner thereof and a pair of leads extending from the corner to provide for the operative connection of the heater to the vehicle battery. The pad comprises a resistance sheet composed of a flexible substrate of glass cloth having a coating of electrically resistive material on one surface. Header and distributor conductors an electrical contact with the face of the coating and connectable to said leads through the time switch are formed by a pair of elongated flexible braided wire electrodes extending sinuously across the coating and stitched to the sheet. Each electrode forms a plurality of U-shaped portions. The electrodes cross each other near their U-bases so that longitudinal stretches of one electrode alternate with longitudinal stretches of the other. The electrodes are electrically insulated from each other at the crossings.

Claims

1. An electrical heater including a heater element comprising a flexible sheet composed of a base layer of electrically insulative material and a coating of electrically resistive conducting material on the base layer, a pair of elongated flexible electrodes of braided wire in electrical contact with the face of the coating, each of the electrodes extending sinuously across the coating width in a plurality of elongated Uportions and one of the electrodes crossing the other near the Ubases so that longitudinal stretches of one electrode alternate with the longitudinal stretches of the other electrode, pieces of electrically insulative material between electrodes at the crossings, stitching securing the electrodes to the sheet, and means for connecting the electrodes to a power source.

2. An electrical heater according to claim 1, wherein the heating element includes a cover of electrically insulative flexible material enclosing the flexible sheet.

3. An electrical heater according to claim 1, including a time switch mounted on the heating element and in circuit with the electrodes to control the current flow through the sheet.

4. A heater according to claim 3, wherein the time switch is mounted on the heating element at a corner thereof, and a pair of external supply leads extend from said corner.

5. A heater according to claim 4, wherein the time switch is connected to one electrode and to an external lead connectable to the positive terminal of a vehicle battery, and the other external lead is connected to the other electrode and is connectable to the vehicle chassis.