Patent USH415H successfully refreshed from Google Patents.
USH415H
Expired / Lapsed
US
⏱️ 0.0 years remaining
Multilayer PTCR thermistor
Assignee: United States Department of the Navy
•
Filing: 1987-04-27
•
Granted: 1988-01-05
•
Expires: 2007-04-27
Abstract
Abstract A multilayer thermistor and a method of making it are disclosed. The thertor has a positive temperature coefficient of resistance (PTCR) and a room temperature resistance lower than prior art thermistors of the same size. The thermistor is comprised of a plurality of layers of material having the PTCR characteristic laminated in alternation with layers of electrodes, the outer two layers of the thermistor being PTCR layers. Alternate electrodes are electrically connected in common to a pair of conductors forming thereby parallel resistance paths across each layer. The more resistance paths the thermistor has, the lower the overall resistance of the device.
Inventors
- 👤 Robert E. Newnham
- 👤 Basavaraj V. Hiremath
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 22:32
CPC Classifications
H; H01; H01C; H01C7/00; H01C7/02; H01C7/021
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
53 words
A thermistor, comprising: a plurality of layers, each layer exhibiting a positive temperature coefficient of resistance; a plurality of electrodes, each electrode being contiguously positioned between adjacent ones of said layers; and a pair of conductors, each being electrically connected to alternate electrodes forming thereby parallel resistance paths across each of said layers.
Claim 2
Dependent Claim
53 words
A thermistor, comprising: a plurality of layers, each layer exhibiting a positive temperature coefficient of resistance; a plurality of electrodes, each electrode being contiguously positioned between adjacent ones of said layers; and a pair of conductors, each being electrically connected to alternate electrodes forming thereby parallel resistance paths across each of said layers.
Claim 3
Dependent Claim
15 words
A thermistor according to claim 1, wherein said layers are composed of mainly barium titanate.
Claim 4
Dependent Claim
13 words
A thermistor according to claim 1, wherein said electrodes are composed of platinum.
Claim 5
Dependent Claim
47 words
A thermistor, comprising: a plurality of layers of barium titanate; a plurality of platinum electrodes, each electrode being contiguously positioned between adjacent ones of said layers; a pair of conductors, each being electrically connected to alternate electrodes forming thereby parallel resistance paths across each of said layers.
Claim 6
Dependent Claim
47 words
A thermistor, comprising: a plurality of layers of barium titanate; a plurality of platinum electrodes, each electrode being contiguously positioned between adjacent ones of said layers; a pair of conductors, each being electrically connected to alternate electrodes forming thereby parallel resistance paths across each of said layers.
Claim 7
Independent Claim
81 words
A method of making a thermistor, comprising the steps of: preparing a mixture of barium titanate with a trace of lanthanum; casting a tape from the mixture; cutting the tape into a plurality of segments; fixing an electrode on one side of all but one of the segments; forming a stack of alternate layers of the segments and electrodes; sintering the stack; and connecting alternate ones of the electrodes in common to form parallel resistance paths across each of the segments.
Claim 8
Independent Claim
81 words
A method of making a thermistor, comprising the steps of: preparing a mixture of barium titanate with a trace of lanthanum; casting a tape from the mixture; cutting the tape into a plurality of segments; fixing an electrode on one side of all but one of the segments; forming a stack of alternate layers of the segments and electrodes; sintering the stack; and connecting alternate ones of the electrodes in common to form parallel resistance paths across each of the segments.
Claim 9
Dependent Claim
69 words
A method according to claim 5, wherein the mixture preparing step comprises: milling BaCO 3 , La 2 O 3 and TiO 2 with a liquid medium to create a first slurry; drying the first slurry to form a powder; calcining the dried powder; remilling the calcined powder with an organic solvent binder, to form a second slurry; and filtering and deaerating the second slurry to form the mixture.
Claim 10
Dependent Claim
23 words
A method according to claim 6 wherein the trace of lanthanum is in the proportion (Ba 0 .9997 La 0 .0003)TiO 3 .
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-01-04 | 1991-07-06 | 1992-01-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-01-04 | 1995-07-06 | 1996-01-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-01-04 | 1999-07-06 | 2000-01-05 | $7700.00 | Window Closed / Lapsed |