Patent ID: 6078248
Filing Date: 2000-06-20
Classification: H01C

Abstract:
A rotary manipulation type variable resistor comprising:(a) a resistance substrate including a first insulating substrate, a horseshoe resistance element layer, and a first connection portion and a second connection portion disposed at each of both ends of said resistance element layer,said horseshoe resistance element layer, said first connection portion and said second connection portion being disposed on said first insulating substrate,said resistance substrate having a first circular notch formed in a center and a notch formed between said first connection portion and second connection portion,said notch reaching from said first circular notch to an outer circumference of said resistance substrate, said resistance element layer being a first printing layer, andeach one of said first connection portion and second connection portion being a second printing layer containing silver,(b) a current collector including a circular conductive layer, and a band conductive layer formed consecutively to said circular conductive layer,said current collector being disposed on a second insulating substrate,said current collector having a second circular notch formed in a center,each one of said circular conductive layer and said band conductive layer being a third printing layer containing silver powder and binder, andsaid circular conductive layer of said current collector and said resistance element layer of said resistance substrate being disposed mutually at a step,(c) a first terminal connected to said first connection portion, a second terminal connected to said second connection portion, and a third terminal connected to said band conductive layer,(d) a case accommodating said resistance substrate and current collector,said case having an opening and a penetration hole,said resistance element layer and said circular conductive layer being in said case, andeach end of said first terminal, second terminal and third terminal projecting from a side face of said case,(e) a manipulation knob disposed to cover said opening,said manipulation knob having a flat part and a shaft projecting from a center of said flat part, andsaid shaft being inserted into said penetration hole,(f) a slider having a first contact point and a second contact point disposed on said flat part of said manipulation knob,said first contact point capable of sliding on a surface of said resistance element layer, while contacting, with said resistance element layer, andsaid second contact point capable of sliding on a surface of said circular conductive layer, while contacting with said circular conductive layer, and(g) wherein said first and second insulating substrates have been cut from the same insulating substrate to form complementary said first and second insulating substrates of the same material.