Claims
- 1. A switch comprising,
- a housing,
- a carrier slideably mounted in said housing,
- a resistance strip mounted in said housing,
- a wiper mounted on said carrier to wipe across said strip from one end to the other of said strip,
- said strip having a ceramic substrate with a thick film of high temperature glass fired thereon and including upper and lower layers of dissimilar resistor material applied on said glass over the same general area, the lower layer having a non-uniform pattern so the resistance between a point along the layer and one end of the lower layer changes in a non-uniform manner, the upper layer having a pattern which completely covers the lower layer and having a higher resistance value than said lower layer, both of said upper and lower layers being fired at a temperature below the firing temperature of said glass and having a glassy smooth surface.
- 2. A switch according to claim 1 including a resistive termination applied to said glass, and in which said multiple layers partially overlap said termination.
- 3. A resistor comprising,
- a ceramic substrate,
- a thick film glass layer fired on said substrate to obtain a glassy smooth surface,
- multiple layers of dissimilar resistive layers fired on said glass layers and having different geometric patterns, the uppermost layer covering the lower layer and having the highest resistive value, said multiple layers having a glassy smooth surface.
- 4. A resistor according to claim 3 in which the melting temperature of said glass layer is higher than the firing temperature of said resistive layers.
- 5. A resistor according to claim 4 including a resistive termination in overlapping relation with an end of said multiple layers.
Parent Case Info
This application is a continuation-in-part of our application Ser. No. 912,391 filed Sept. 26, 1986, now abandoned.
US Referenced Citations (2)
Number |
Name |
Date |
Kind |
4495524 |
Kakuhashi et al. |
Jan 1985 |
|
4680570 |
Hehl |
Jul 1987 |
|
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
912391 |
Sep 1986 |
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