Patent US4679890A successfully refreshed from Google Patents.
Patent US4629869A successfully refreshed from Google Patents.
US4629869A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Self-limiting heater and resistance material
Assignee: Individual
•
Filing: 1983-11-08
•
Granted: 1986-12-16
•
Expires: 2003-11-08
Abstract
Abstract A self limiting electrical heating device with an electrical resistance material the resistivity of which is changed by more than a power of (10) within a predetermined, narrow temperature interval and which is arranged between electrical conductors connectable to a voltage source, the conductors and the resistance material being enclosed in an electrically insulating cover. The electrical resistance material (2) comprises: (1) an electrically relatively non-conducting crystalline, monomeric substance which melts within or near the predetermined, narrow temperature interval and which constitutes the outer phase, (2) particles of one or more electrically conducting materials(s), distributed in the non-conducting material, (3) one or more non-conducting powdered or fibrous fillers, which are insoluable in the non-conducting material and which have a considerably higher melting point than this material, similarly distributed in the non-conducting material, whereby the weight ratio between components (1) and (3) is from 10:90 to 90:10.
Inventors
- 👤 Wolfgang A. Bronnvall
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 19:41
CPC Classifications
H; H01; H01C; H01C7/00; H01C7/02; H01C7/028; H05; H05B; H05B3/00; H05B3/10; H05B3/12; H05B3/14; H05B3/146; H05B3/40; H05B3/54; H05B3/56
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
146 words
A self-limiting electrical heating device comprising an electrical resistance material the resistivity of which is changed by more than a power of 10 within a predetermined, narrow temperature interval and which is arranged between electrical conductors connectable to a voltage source, the conductors and the resistance material being enclosed in an electrically insulating cover, characterized in that the electrical resistance material comprises (1) an electrically relatively non-conducting, crystalline, monomeric substance which melts at about the predetermined narrow temperature interval and which constitutes the outer phase, (2) particles of at least one electrically conducting material distributed in the non-conducting material, (3) at least one non-conducting particulate filler said filler being insoluble in the non-conducting material and having a considerably higher melting point than the non-conducting material, similarly distributed in the non-conducting material, whereby the weight ratio between the components (1) and (3) is from 10:90 to 90:10.
Claim 2
Dependent Claim
146 words
A self-limiting electrical heating device comprising an electrical resistance material the resistivity of which is changed by more than a power of 10 within a predetermined, narrow temperature interval and which is arranged between electrical conductors connectable to a voltage source, the conductors and the resistance material being enclosed in an electrically insulating cover, characterized in that the electrical resistance material comprises (1) an electrically relatively non-conducting, crystalline, monomeric substance which melts at about the predetermined narrow temperature interval and which constitutes the outer phase, (2) particles of at least one electrically conducting material distributed in the non-conducting material, (3) at least one non-conducting particulate filler said filler being insoluble in the non-conducting material and having a considerably higher melting point than the non-conducting material, similarly distributed in the non-conducting material, whereby the weight ratio between the components (1) and (3) is from 10:90 to 90:10.
Claim 3
Dependent Claim
18 words
Heating device according to claim 1, characterized in that component (1), the non-conducting meltable substance, contains polar groups.
Claim 4
Dependent Claim
17 words
Heating device according to claim 2, characterized in that the non-conducting meltable substance contains carboxylic acid groups.
Claim 5
Dependent Claim
16 words
Heating device according to claim 2, characterized in that the non-conducting meltable substance contains alcohol groups.
Claim 6
Dependent Claim
14 words
Heating device according to claim 1, characterized in that it constitutes a heating cable.
Claim 7
Dependent Claim
15 words
Heating device according to claim 1 characterized in that it constitutes an electrical wall element.
Claim 8
Dependent Claim
118 words
An electrical resistance material, the resistivity of which is changed by more than a power of 10 within a predetermined, narrow temperature interval, for use in self-limiting electrical heating devices, characterized in that the electrical resistance material comprises (1) an electrically relatively non-conducting, crystalline, monomeric substance which melts at about the predetermined narrow temperature interval and which constitutes the outer phase, (2) particles of at least one electrically conducting material, distributed in the non-conducting material, (3) at least one non-conducting particulate filler insoluble in the non-conducting material and having a considerably higher melting point than the non-conducting material, similarly distributed in the non-conducting material, whereby the weight ratio between components (1) and (3) is from 10:90 to 90:10.
Claim 9
Dependent Claim
118 words
An electrical resistance material, the resistivity of which is changed by more than a power of 10 within a predetermined, narrow temperature interval, for use in self-limiting electrical heating devices, characterized in that the electrical resistance material comprises (1) an electrically relatively non-conducting, crystalline, monomeric substance which melts at about the predetermined narrow temperature interval and which constitutes the outer phase, (2) particles of at least one electrically conducting material, distributed in the non-conducting material, (3) at least one non-conducting particulate filler insoluble in the non-conducting material and having a considerably higher melting point than the non-conducting material, similarly distributed in the non-conducting material, whereby the weight ratio between components (1) and (3) is from 10:90 to 90:10.
Claim 10
Dependent Claim
14 words
Heating device according to claim 2, characterized in that it constitutes a heating cable.
Claim 11
Dependent Claim
14 words
Heating device according to claim 3, characterized in that it constitutes a heating cable.
Claim 12
Dependent Claim
14 words
Heating device according to claim 4, characterized in that it constitutes a heating cable.
Claim 13
Dependent Claim
15 words
Heating device according to claim 2, characterized in that it constitutes an electrical wall element.
Claim 14
Dependent Claim
15 words
Heating device according to claim 3, characterized in that it constitutes an electrical wall element.
Claim 15
Dependent Claim
15 words
Heating device according to claim 4, characterized in that it constitutes an electrical wall element.
Claim 16
Dependent Claim
43 words
A self-limiting electrical heating device having an electrical resistance material arranged between electrical conductors connectable to a voltage source, the conductors and resistance material being enclosed in an electrically insulating cover, and wherein said electrical resistance material is the material of claim 7.
Claim 17
Dependent Claim
26 words
A self-limiting electrical heating device according to claim 1 having a power development in said electrical resistance material not exceeding 2 watts per cm 3 .
Claim 18
Dependent Claim
23 words
A self-limiting electrical heating device according to claim 1 wherein said electrical resistance material has a resistivity greater than 10 4 ohm cm.
Claim 19
Dependent Claim
23 words
A self-limiting electrical heating device according to claim 1 wherein said electrical resistance material has a melting point interval not exceeding 5° C.
Claim 20
Dependent Claim
25 words
A self-limiting electrical heating device in accordance with claim 1 wherein said electrically relatively non-conducting, crystalline, monomeric substance has a molecular weight less than 500.
Claim 21
Dependent Claim
62 words
A self-limiting electrical heating device according to claim 1 wherein said electrical resistance material has a power development not exceeding 5 watts per cm 3 , a resistivity greater than 10 3 ohm CM, and a melting point interval of no more than 10° C., and said electrically relatively non-conducting, crystalline, monomeric substance has a melecular weight which is less than 1,000.
References Cited (Backward Citations)
CH181635A
Cited
GB675752A
Cited
US3243753A
Cited
DE2103319A1
Cited
US3673121A
Cited
DE2634931A1
Cited
US4188276A
Cited
US4388607A
Cited
US4200973A
Cited
US4304987A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-12-15 | 1990-06-16 | 1990-12-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-12-15 | 1994-06-16 | 1994-12-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-12-15 | 1998-06-16 | 1998-12-16 | $7700.00 | Window Closed / Lapsed |