Patent US4936145A successfully refreshed from Google Patents.
US4936145A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heatable electric resistor for flow meters
Assignee: Evonik Operations GmbH
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Filing: 1989-06-30
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Granted: 1990-06-26
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Expires: 2009-06-30
Abstract
Abstract A heatable electric resistor for flow meters with short response time and as small a resistance value as possible with meandering printed lines of differing widths is obtained if separate systems of printed lines which are connected parallel to each other or are connected parallel to each other and in series are formed by means of separating cuts and if systems of printed lines which are connected parallel to each other exhibit the same electric resistance.
Inventors
- 👤 Martin Hohenstatt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 19:07
CPC Classifications
H; H05; H05B; H05B3/00; H05B3/20; H05B3/22; H05B3/26; G; G01; G01F; G01F1/00; G01F1/68; G01F1/684; G01F1/688; G01F1/69; G01F1/692; G01P; G01P5/00; G01P5/10; G01P5/12; H05B2203/00; H05B2203/002; H05B2203/003; H05B2203/013; H05B2203/017; H05B2203/021; H05B2203/022; H05B2203/037
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
231 words
A heatable electric resistor apparatus for measurement of flow speed or mass flow of a flowing medium, said apparatus comprising: an electrically insulating substrate provided in the form of a plate to have two relatively large surfaces which can be aligned parallel to the direction of flow, and a facing edge which defines a plane which can be aligned perpendicular to the direction of flow; and thin metal layers on one of said large surfaces of said substrate, said layers being cut by cut lines which extend in directions both parallel and perpendicular to the direction of flow to define contact surface, a first system of printed lines which forms a first meandering path of electrical resistance, and a second system of printed lines which forms a second meandering path that has the same electrical resistance as said first path and is electrically in parallel with said first path, said paths comprising an equal number of said printed lines, said printed lines of both paths being generally oriented in a direction perpendicular to the direction of flow and having widths that vary in the direction of flow away from that printed line of each path which is nearest said facing edge of said substrate so that the electrical heating power density in each printed line decreases in the same degree as the heat flow density removed locally by the flowing medium.
Claim 2
Dependent Claim
231 words
A heatable electric resistor apparatus for measurement of flow speed or mass flow of a flowing medium, said apparatus comprising: an electrically insulating substrate provided in the form of a plate to have two relatively large surfaces which can be aligned parallel to the direction of flow, and a facing edge which defines a plane which can be aligned perpendicular to the direction of flow; and thin metal layers on one of said large surfaces of said substrate, said layers being cut by cut lines which extend in directions both parallel and perpendicular to the direction of flow to define contact surface, a first system of printed lines which forms a first meandering path of electrical resistance, and a second system of printed lines which forms a second meandering path that has the same electrical resistance as said first path and is electrically in parallel with said first path, said paths comprising an equal number of said printed lines, said printed lines of both paths being generally oriented in a direction perpendicular to the direction of flow and having widths that vary in the direction of flow away from that printed line of each path which is nearest said facing edge of said substrate so that the electrical heating power density in each printed line decreases in the same degree as the heat flow density removed locally by the flowing medium.
Claim 3
Dependent Claim
20 words
An apparatus as claimed in claim 1, wherein between said contacts, said resistance paths are electrically isolated from each other.
Claim 4
Dependent Claim
38 words
An apparatus as claimed in claim 1, wherein said contact surfaces are provided at regions including opposite end edges of said substrate, said opposite edges and therefore said contact surfaces extending generally parallel to the direction of flow.
Claim 5
Dependent Claim
32 words
An apparatus as claimed in claim 1, wherein said contact surfaces are provided at a region including an edge of said substrate, said edge extending generally parallel to the direction of flow.
Claim 6
Dependent Claim
125 words
An apparatus as claimed in claim 1, wherein said first and second paths have ends which are situated next to each other, and said apparatus further comprises a third system of printed lines which forms a third resistance path connecting said situated ends of said first and second paths to one of said contact surfaces, said printed lines of said third path being generally oriented in a direction perpendicular to the direction of flow and having widths that vary in the direction of flow away from a printed line of said third path which is nearest said facing edge of said substrate so that the electrical heating power density decrease in the same degree as the heat flow density removed locally by the flowing medium.
Claim 7
Dependent Claim
47 words
An apparatus as claimed in claim 1, wherein one printed line of said first path and one printed line of said second path each extend, in a direction perpendicular to the direction of flow, over the entire length of said side of said substrate between said contacts.
Claim 8
Dependent Claim
68 words
An apparatus as claimed in claim 6, wherein said one printed line of said first path which extends over the length of said substrate side is provided in a region including a leading edge of said substrate side and said one printed line of said second path which extends over the length of said substrate side is provided in a region including the edge opposite said leading edge.
Claim 9
Dependent Claim
32 words
An apparatus as claimed in claim 1, wherein the width of the transition between two adjacent printed lines of a path is an average value of the widths of such adjacent lines.
References Cited (Backward Citations)
US4449402A
Cited
JPS60236029A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-06-25 | 1993-12-25 | 1994-06-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-06-25 | 1997-12-25 | 1998-06-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-06-25 | 2001-12-25 | 2002-06-26 | $7700.00 | Window Closed / Lapsed |