| 摘要 |
PURPOSE:To enable a voltage drop through a common conductor to be reduced and heating elements to be gathered close to an end face through a simple construction, by providing an insulator layer on a conductive substrate to use it in place of an insulating substrate and passing an electric current in the conductive substrate. CONSTITUTION:The insulator layer 2 is provided on the conductive substrate 1a, so that an electric current to be passed to the heating element 4 flows into the element 4 through an individual terminal 6 and an individual conductor 5, and flows to the common conductor 7a. The part of the common conductor 7a is provided on a part 3a devoid of the insulator layer 2, so that the current flows into the substrate 1a after flowing from the common conductor 7a into the part 3a devoid of the insulator layer 2. The current flows through the part 3b devoid of the insulator layer 2, and flows out to a common terminal through the common conductor 7b. Accordingly, the resistance of the path of the common conductor 7a substrate 1a common conductor 7b is reduced, the voltage drop therethrough is reduced, printed density is made uniform, the heating elements can be gathered close to the end face, and an end face type system can be inexpensively provided. |
