US5884391A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for manufacturing an electrical device comprising a PTC element
Assignee: Littelfuse Inc
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Filing: 1997-06-30
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Granted: 1999-03-23
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Expires: 2017-06-30
Abstract
Abstract An electrical device comprising a resistive element having a first electrode in electrical contact with the top surface of the resistive element and a second electrode in electrical contact with the bottom surface of the resistive element. An insulating layer is formed on the first and second electrodes. A portion of the insulating layer is removed from the first and second electrodes to form first and second contact points. A conductive layer is formed on the insulating layer and makes electrical contact with the first and second electrodes at the contact points. The conductive layer has portions removed to form first and second end terminations separated by electrically non-conductive gaps. The wrap-around configuration of the device allows for an electrical connection to be made to both electrodes from the same side of the electrical device.
Inventors
- 👤 Katherine M. McGuire
- 👤 Honorio Luciano
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 18:05
CPC Classifications
H; H01; H01C; H01C1/00; H01C1/14; H01C1/1406; H01C1/142; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49082; Y10T29/49085; Y10T29/49101; Y10T29/49117; Y10T29/49204; Y10T29/49789; Y10T29/4979
Claims Analysis
Total Claims: 35
Claim 1
Independent Claim
151 words
A method for manufacturing an electrical device comprising the steps of: providing a laminar PTC sheet having a top and bottom surface, a first electrode formed on the top surface, and a second electrode formed on the bottom surface; creating a plurality of strips in a regular pattern in the laminar PTC sheet; forming a plurality of electrically non-conductive gaps in the first and second electrodes; coating the strips in the laminar PTC sheet with an insulating layer; removing portions of the insulating layer to expose opposed end portions of the PTC sheet and portions of the first and second electrodes; applying a first conductive layer to the exposed end portions of the PTC sheet to form end terminations, the end terminations making electrical contact with the exposed portions of the first and second electrodes, respectively; and, dividing each strip in the laminar PTC sheet into a plurality of electrical devices.
Claim 2
Independent Claim
151 words
A method for manufacturing an electrical device comprising the steps of: providing a laminar PTC sheet having a top and bottom surface, a first electrode formed on the top surface, and a second electrode formed on the bottom surface; creating a plurality of strips in a regular pattern in the laminar PTC sheet; forming a plurality of electrically non-conductive gaps in the first and second electrodes; coating the strips in the laminar PTC sheet with an insulating layer; removing portions of the insulating layer to expose opposed end portions of the PTC sheet and portions of the first and second electrodes; applying a first conductive layer to the exposed end portions of the PTC sheet to form end terminations, the end terminations making electrical contact with the exposed portions of the first and second electrodes, respectively; and, dividing each strip in the laminar PTC sheet into a plurality of electrical devices.
Claim 3
Dependent Claim
20 words
The method of claim 1 further including the step of applying a second conductive layer on the first conductive layer.
Claim 4
Dependent Claim
36 words
The method of claim 1, wherein the step of forming the first and second electrodes on the top and bottom surfaces of the PTC sheet comprises laminating the PTC sheet between a pair of metal foils.
Claim 5
Dependent Claim
28 words
The method of claim 1, wherein the step of forming the first and second electrodes on the top and bottom surfaces of the PTC sheet comprises electroless plating.
Claim 6
Dependent Claim
28 words
The method of claim 1, wherein the step of forming the first and second electrodes on the top and bottom surfaces of the PTC sheet comprises electrolytic plating.
Claim 7
Dependent Claim
25 words
The method of claim 1, wherein the insulating layer is a material selected from the group consisting of photo resist, dielectric, ceramic and solder mask.
Claim 8
Dependent Claim
30 words
The method of claim 1, wherein the step of coating the strips in the laminar PTC sheet with an insulating layer comprises screen printing the insulating layer onto the strips.
Claim 9
Dependent Claim
29 words
The method of claim 1, wherein the step of coating the strips in the laminar PTC sheet with an insulating layer comprises spraying the insulating layer onto the strips.
Claim 10
Dependent Claim
27 words
The method of claim 1, wherein the first conductive layer is a metal selected from the group consisting of copper, tin, nickel, silver, gold and alloys thereof.
Claim 11
Dependent Claim
49 words
The method of claim 1, wherein the step of forming the plurality of electrically non-conductive gaps comprises the further steps of: applying a masking material to the first and second electrodes, leaving portions of the electrodes unmasked; and, etching away the unmasked portions of the first and second electrodes.
Claim 12
Dependent Claim
22 words
The method of claim 10 wherein the step of forming the plurality of electrically non-conductive gaps includes etching with an acid solution.
Claim 13
Dependent Claim
26 words
The method of claim 1, wherein the second conductive layer comprises solder and is applied to the first conductive layer by electrolytic plating or solder dipping.
Claim 14
Dependent Claim
22 words
The method of claim 1, wherein the strips created in the laminar PTC sheet have a width, W, less than 0.20 inch.
Claim 15
Dependent Claim
28 words
The method of claim 1, further including the step of dividing each strip into a plurality of electrical devices comprises applying pressure to a plurality of break points.
Claim 16
Dependent Claim
20 words
The method of claim 1, wherein each electrical device formed has an area of less than 0.060 inch 2 .
Claim 17
Independent Claim
176 words
A method for manufacturing an electrical device comprising the steps of: providing a laminar resistive element having first and second surfaces and opposed end portions; forming a first electrode on the first surface of the resistive element; forming a second electrode on the second surface of the resistive element; creating an electrically non-conductive gap in each of the first and the second electrodes; applying an insulating layer to the first and second electrodes and the opposed end portions of the laminar resistive element; curing the insulating layer on portions of the first and second electrodes; removing the insulating layer from the end portions of the laminar resistive element and from the uncured portions of the first and second electrodes; and, applying a first conductive layer to the exposed end portions of the laminar resistive element to form first and second end terminations, the first end termination making electrical contact with the first electrode and the second end termination making electrical contact with the second electrode; and, applying a second conductive layer to the first conductive layer.
Claim 18
Independent Claim
176 words
A method for manufacturing an electrical device comprising the steps of: providing a laminar resistive element having first and second surfaces and opposed end portions; forming a first electrode on the first surface of the resistive element; forming a second electrode on the second surface of the resistive element; creating an electrically non-conductive gap in each of the first and the second electrodes; applying an insulating layer to the first and second electrodes and the opposed end portions of the laminar resistive element; curing the insulating layer on portions of the first and second electrodes; removing the insulating layer from the end portions of the laminar resistive element and from the uncured portions of the first and second electrodes; and, applying a first conductive layer to the exposed end portions of the laminar resistive element to form first and second end terminations, the first end termination making electrical contact with the first electrode and the second end termination making electrical contact with the second electrode; and, applying a second conductive layer to the first conductive layer.
Claim 19
Dependent Claim
34 words
The method of claim 16, wherein the step of curing the insulating layer further includes masking portions of the top and bottom insulating layer, while leaving the end portions of the insulating layer unmasked.
Claim 20
Dependent Claim
27 words
The method of claim 17 wherein the step of curing the insulating layer further includes treating the unmasked portions of the insulating layers with an ultraviolet light.
Claim 21
Dependent Claim
12 words
The method of claim 16, wherein the resistive element exhibits PTC behavior.
Claim 22
Dependent Claim
18 words
The method of claim 19, wherein the resistive element comprises a polymer component and a conductive filler component.
Claim 23
Dependent Claim
11 words
The method of claim 20, wherein the polymer component comprises polyethylene.
Claim 24
Dependent Claim
14 words
The method of claim 20, wherein the polymer component comprises polyethylene and maleic anhydride.
Claim 25
Dependent Claim
12 words
The method of claim 16, wherein the second conductive layer comprises solder.
Claim 26
Dependent Claim
13 words
The method of claim 16, wherein the first and second electrode comprise nickel.
Claim 27
Independent Claim
145 words
A method for manufacturing an electrical device comprising the steps of: providing a laminar conductive sheet having a first and second surface and opposed end portions, a first electrode formed on the first surface, and a second electrode formed on the second surface; creating a plurality of strips in the laminar conductive sheet; forming a plurality of electrically non-conductive gaps in the first and second electrodes; coating the strips in the laminar conductive sheet with an insulating layer; removing portions of the insulating layer to expose the opposed end portions of the laminar conductive sheet and to expose portions of the first and second electrodes; applying a first conductive layer to the exposed end portions of the conductive sheet and to the exposed portions of the first and second electrodes; and, dividing each strip in the laminar conductive sheet into a plurality of electrical devices.
Claim 28
Independent Claim
145 words
A method for manufacturing an electrical device comprising the steps of: providing a laminar conductive sheet having a first and second surface and opposed end portions, a first electrode formed on the first surface, and a second electrode formed on the second surface; creating a plurality of strips in the laminar conductive sheet; forming a plurality of electrically non-conductive gaps in the first and second electrodes; coating the strips in the laminar conductive sheet with an insulating layer; removing portions of the insulating layer to expose the opposed end portions of the laminar conductive sheet and to expose portions of the first and second electrodes; applying a first conductive layer to the exposed end portions of the conductive sheet and to the exposed portions of the first and second electrodes; and, dividing each strip in the laminar conductive sheet into a plurality of electrical devices.
Claim 29
Dependent Claim
13 words
The method of claim 25, wherein the laminar conductive sheet exhibits PTC behavior.
Claim 30
Dependent Claim
22 words
The method of claim 25, wherein a plurality of break points are formed on the top and bottom surface of each strip.
Claim 31
Dependent Claim
17 words
The method of claim 25, wherein a second conductive layer is formed on the first conductive layer.
Claim 32
Dependent Claim
88 words
The method of claim 25, wherein the step of removing the insulating layer to expose the opposed end portions of the laminar conductive sheet includes: covering a portion of the insulating layer overlapping the electrodes on the top and bottom surfaces with a masking material, while leaving the insulating layer on end portions of the conductive sheet unmasked; treating the unmasked portions of the insulating layer with an ultraviolet light; and, removing the masked portions of the insulating layer and exposing the end portions of the conductive sheet.
Claim 33
Independent Claim
193 words
A method for manufacturing an electrical device comprising the steps of: providing a laminar resistive element having first and second surfaces and first and second end portions; forming a first electrode on the first surface of the resistive element; forming a second electrode on the second surface of the resistive element; forming at least one electrically non-conductive gap in the first electrode adjacent to the first end portion of the laminar resistive element; forming at least a second electrically non-conductive gap in the second electrode and spaced inwardly from the second end portion; applying an insulating layer to the first and second electrodes and opposed end portions of the laminar resistive element; curing the insulating layer on portions of the first and second electrodes; removing the insulating layer to expose the end portions of the laminar resistive element and to expose portions of the first and second electrodes; and, applying a first conductive layer to the exposed end portions of the laminar resistive element and to the exposed portions of the first and second electrodes to form first and second end terminations; and, applying a second conductive layer to the first conductive layer.
Claim 34
Independent Claim
193 words
A method for manufacturing an electrical device comprising the steps of: providing a laminar resistive element having first and second surfaces and first and second end portions; forming a first electrode on the first surface of the resistive element; forming a second electrode on the second surface of the resistive element; forming at least one electrically non-conductive gap in the first electrode adjacent to the first end portion of the laminar resistive element; forming at least a second electrically non-conductive gap in the second electrode and spaced inwardly from the second end portion; applying an insulating layer to the first and second electrodes and opposed end portions of the laminar resistive element; curing the insulating layer on portions of the first and second electrodes; removing the insulating layer to expose the end portions of the laminar resistive element and to expose portions of the first and second electrodes; and, applying a first conductive layer to the exposed end portions of the laminar resistive element and to the exposed portions of the first and second electrodes to form first and second end terminations; and, applying a second conductive layer to the first conductive layer.
Claim 35
Dependent Claim
127 words
The method of claim 30, wherein the step of removing the insulating layer to expose the opposed end portions of the laminar conductive sheet includes: covering a portion of the insulating layer overlapping the electrodes on the top and bottom surfaces with a masking material, while leaving an unmasked L-shaped insulating layer on the first end portion of the conductive sheet; covering a portion of the insulating layer overlapping the electrodes on the top and bottom surfaces with a masking material, while leaving an unmasked U-shaped insulating layer on the second end portion of the conductive sheet; treating the unmasked portions of the insulating layer with an ultraviolet light; and, removing the masked portions of the insulating layer and exposing the end portions of the conductive sheet.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-03-22 | 2002-09-21 | 2003-03-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-03-22 | 2006-09-21 | 2007-03-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-03-22 | 2010-09-21 | 2011-03-23 | $7700.00 | Window Closed / Lapsed |