Patent US5202547A successfully refreshed from Google Patents.
← Back to Patent Explorer
US5202547A Expired / Lapsed US ⏱️ 0.0 years remaining

Resistance adjusting type heater

Assignee: NGK Insulators Ltd
•
Filing: 1992-02-28
•
Granted: 1993-04-13
•
Expires: 2012-02-28
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A resistance adjusting type heater has a honeycomb structure having a large number of passages, at least two electrodes to enable electrical heating of the honeycomb structure provided on the honeycomb structure, and a resistance adjusting means, a slit, provided between the electrodes. The thicknesses of passage walls at the portions of the honeycomb structure at which electricity flows at a very high density are increased with a conductive material to prevent the abnormal heat generation at the portions of the honeycomb structure.

Inventors

  • 👤 Fumio Abe
  • 👤 Hiroshige Mizuno
  • 👤 Takashi Harada
  • 👤 Tomoharu Kondo

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 15:22
CPC Classifications
B; B01; B01J; B01J35/00; B01J35/30; B01J35/33; F; F01; F01N; F01N3/00; F01N3/08; F01N3/10; F01N3/18; F01N3/20; F01N3/2006; F01N3/2013; F01N3/2026; F01N3/24; F01N3/28; F01N3/2803; H; H05; H05B; H05B3/00; H05B3/10; H05B3/12; H05B3/14; F01N2330/00; F01N2330/02; F01N2330/04; F01N2510/00; F01N2510/06; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12; Y10; Y10S; Y10S55/00; Y10S55/30; Y10T; Y10T428/00; Y10T428/24; Y10T428/24149

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 82 words
A resistance adjusting type heater comprising: a honeycomb structure having a number of passages defined by passage walls; at least two electrodes in electrical contact with said honeycomb structure; and at least one slit extending at least partially through said honeycomb structure to alter the electrical resistance thereof, wherein a passage wall defining a front edge of said slit where said slit terminates in said honeycomb structure has an increased thickness, said edge corresponding to an area of relatively high current density.
Claim 2
Dependent Claim 82 words
A resistance adjusting type heater comprising: a honeycomb structure having a number of passages defined by passage walls; at least two electrodes in electrical contact with said honeycomb structure; and at least one slit extending at least partially through said honeycomb structure to alter the electrical resistance thereof, wherein a passage wall defining a front edge of said slit where said slit terminates in said honeycomb structure has an increased thickness, said edge corresponding to an area of relatively high current density.
Claim 3
Dependent Claim 18 words
The heater of claim 1, wherein a plurality passage walls surrounding said front edge have an increased thickness.
Claim 4
Dependent Claim 78 words
A resistance adjusting type heater comprising: a honeycomb structure having a number of passages; at least two electrodes in electrical contact with said honeycomb structure; and at least one slit extending at least partially through said honeycomb structure to alter the electrical resistance thereof, wherein conductive material is disposed within a passage along a front edge of said slit where said slit terminates in said honeycomb structure, said edge corresponding to an area of relatively high current density.
Claim 5
Dependent Claim 78 words
A resistance adjusting type heater comprising: a honeycomb structure having a number of passages; at least two electrodes in electrical contact with said honeycomb structure; and at least one slit extending at least partially through said honeycomb structure to alter the electrical resistance thereof, wherein conductive material is disposed within a passage along a front edge of said slit where said slit terminates in said honeycomb structure, said edge corresponding to an area of relatively high current density.
Claim 6
Dependent Claim 18 words
The heater of claim 3, wherein a plurality passages surrounding said front edge are filled with conductive material.

References Cited (Backward Citations)

JPS5023138A Cited
GB1492929A Cited
JPS6167609A Cited
US4717813A Cited
EP0283220A1 Cited
WO1989010471A1 Cited
US5063029A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1996-04-12 1996-10-12 1997-04-13 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2000-04-12 2000-10-12 2001-04-13 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2004-04-12 2004-10-12 2005-04-13 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag