Electrically heated window
AssigneePPG Industries, Inc.
InventorsHarry S. Koontz, John P. Forr
Life of this patent
Estimating the term…
Abstract
An electrical resistance heated window having at least three heatable zones and at least one of the heatable zones is generally centrally located on the window and can be heated faster to a higher temperature than the other of the zones for faster defogging and deicing of that particular zone.
Claims13
An electrically heated window comprising four electrical resistance heating elements, each of said heating elements having an upper and lower bus bar positioned along top and bottom edge portions of said window and a plurality of electrically conducting resistive filaments extending therebetween, wherein a first heating element generally defines a first outer heatable zone generally at one end of said window, a second heating element generally defines a second outer heatable zone generally at the other end of said window, a third heating element generally defines a first central heatable zone generally adjacent to and inboard of said second heatable zone and a fourth heating element generally defines a second central heating zone positioned between said first and third heatable zones, and further wherein said lower but bar of said first heating element is connected to said lower bus bar of said second heating element, said upper bus bar of said second heating element is connected to said upper bus bar of said third heating element and said lower bus bar of said third heating element is connected to said lower bus bar of said fourth heating element, and a first electrical connecting means connected to said upper bus bar of said first heating element and a second electrical connecting means connected to said upper bus bar of said fourth heating element generally in close proximity to said first connecting means, said resistive filaments of said heating elements being configured to provide a heating system geometry for said heated window which produces more rapid heating in said third and fourth heating elements than in said first and second heating elements.
Dependencies are inferred from the claim text.