Patent US4333350A successfully refreshed from Google Patents.
EP0334473A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Method of making a film-type resistor
Assignee: Individual
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Filing: 1989-02-07
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Granted: —
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Expires: 2009-02-07
Abstract
Abstract A film-type resistor comprises a cylindrical substrate (10), a film of resistive material (11) on the surface of the substrate and an insulating and environmentally protective coating (19) over the resistive film. End caps (20) are applied after the protective coating (19) to establish electrical contact with the resistive film (11). Preferably the environmentally protective coating (19) is applied by screen printing and a highly conductive film (17) is applied to establish electrical contact between the resistive film (11) and the end caps (20).
Inventors
- 👤 Richard E. Caddock
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 23:24
CPC Classifications
H; H01; H01C; H01C7/00; H01C7/006; H01C1/00; H01C1/02; H01C1/034; H01C1/14; H01C1/148; H01C17/00; H01C17/02; H01C17/28; H01C7/003; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49082
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
95 words
A film-type resistor comprising: (a) a cylindrical substrate (10); (b) a film (11) of resistive material provided around at least portions of the exterior surface of the substrate (10) and conforming to the surface of the substrate (10); (c) a coating(19) of environmentally protective insulating material provided over the resistive film (11) to insulate and environmentally protect it; and, (d) electrically conductive end caps (20) provided on opposite ends of the substrate and being electrically connected to the resistive film (11), characterised in that the coating (19) does not extend over the end caps (20).
Claim 2
Dependent Claim
95 words
A film-type resistor comprising: (a) a cylindrical substrate (10); (b) a film (11) of resistive material provided around at least portions of the exterior surface of the substrate (10) and conforming to the surface of the substrate (10); (c) a coating(19) of environmentally protective insulating material provided over the resistive film (11) to insulate and environmentally protect it; and, (d) electrically conductive end caps (20) provided on opposite ends of the substrate and being electrically connected to the resistive film (11), characterised in that the coating (19) does not extend over the end caps (20).
Claim 3
Dependent Claim
35 words
A resistor according to claim 1, which also includes: (e) a high conductivity termination film (17) applied to the ends of the substrate electrically to connect the resistive film (11) and the end caps (20).
Claim 4
Dependent Claim
45 words
A resistor according to claim 1 or 2, in which the end caps (20) are press-fitted to the ends of the substrate and are in interference fit with the coating (19) and with the resistive film (11) or conductive film (17) when this is included.
Claim 5
Dependent Claim
67 words
A resistor according to any one of the preceding claims, in which the environmentally protective coating (19) is one which has been formed by screen printing and has a precisely controlled uniform thickness and has a precisely controlled area of application, the area of application not including at least portions of the resistive film (11) or the termination films (17) which lie beneath the end caps (20).
Claim 6
Dependent Claim
67 words
A resistor according to any one of the preceding claims, in which the resistive film (11) has a gap (14) extending longitudinally of the substrate, and in which the coating (19) of environmentally protective material also has a gap extending longitudinally of the substrate, the gaps being substantially in register with one another with all regions of the resistive film (11) being covered by the coating (20).
Claim 7
Independent Claim
98 words
A method of manufacturing a film type cylindrical resistor, the method comprising: (a) providing a cylindrical substrate (10); (b) providing a film (11) of resistive material on the outside of the substrate (10); (c) providing over the resistive material film at least one layer of environmentally protective insulating material (19); and (d) providing electrically conductive end caps (20) over opposite ends of the substrate (10) and causing the end caps to be electrically coupled to the resistive film material (11), characterised in that the end caps (20) are provided after the environmentally protective insulating material has been applied.
Claim 8
Independent Claim
98 words
A method of manufacturing a film type cylindrical resistor, the method comprising: (a) providing a cylindrical substrate (10); (b) providing a film (11) of resistive material on the outside of the substrate (10); (c) providing over the resistive material film at least one layer of environmentally protective insulating material (19); and (d) providing electrically conductive end caps (20) over opposite ends of the substrate (10) and causing the end caps to be electrically coupled to the resistive film material (11), characterised in that the end caps (20) are provided after the environmentally protective insulating material has been applied.
Claim 9
Dependent Claim
36 words
A method according to claim 6, in which a high conducting film (17) is applied to the ends of the substrate (10) to establish electrical coupling between the resistive film (11) and the end caps (20).
Claim 10
Dependent Claim
34 words
A method according to claim 6 or 7, in which the environmentally protective material is subjected to a curing step at an elevated temperature before the end caps (20) are provided in step (d).
Claim 11
Independent Claim
51 words
A method according to any one of claims 6, 7 or 8, in which step (b) comprises screen printing a coating of screen-printable environmentally protective insulating material over the resistive film (11) but not over at least some portions of the substrate (10) to be covered by the end caps (20).
Claim 12
Independent Claim
60 words
A method according to any one of claims 6 to 9, in which the step (d) comprises press-fitting the electrically conductive end caps (20) over the ends of the substrate, the end caps being an interference-fit relationship with the resistive film (11) or the conductive film (17) and also with portions of the coating (19) of environmentally protective insulating material.
References Cited (Backward Citations)
No citation records indexed.
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