US4967176A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Assemblies of PTC circuit protection devices
Assignee: Tyco International Ltd Bermuda
•
Filing: 1988-07-15
•
Granted: 1990-10-30
•
Expires: 2008-07-15
Abstract
Abstract A device assembly in which a plurality of PTC circuit protection devices are connected in series. Assemblies of this type are useful in providing protection under voltage conditions which would be unsafe for an individual protection device. In a preferred system the device assembly is connected in series with a circuit breaker.
Inventors
- 👤 David A. Horsma
- 👤 Hundi P. Kamath
- 👤 Shou-Mean Fang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 16:28
CPC Classifications
H; H02; H02H; H02H9/00; H02H9/02; H02H9/026; H01; H01H; H01H33/00; H01H33/02; H01H33/04; H01H33/16; H01H33/161; H01H2033/163
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
47 words
A device assembly which comprises at least three circuit protection devices connected in series, each of said devices comprising a laminar PTC element which is sandwiched between two laminar metal electrodes, the PTC elements being stacked on top of each other but separated by laminar metal electrodes.
Claim 2
Independent Claim
47 words
A device assembly which comprises at least three circuit protection devices connected in series, each of said devices comprising a laminar PTC element which is sandwiched between two laminar metal electrodes, the PTC elements being stacked on top of each other but separated by laminar metal electrodes.
Claim 3
Dependent Claim
18 words
An assembly according to claim 1 wherein each of the PTC elements is composed of a conductive polymer.
Claim 4
Independent Claim
26 words
A device assembly which comprises a plurality of sets of PTC circuit protection devices connected in series, the sets being connected in parallel with each other.
Claim 5
Independent Claim
26 words
A device assembly which comprises a plurality of sets of PTC circuit protection devices connected in series, the sets being connected in parallel with each other.
Claim 6
Dependent Claim
14 words
An assembly according to claim 3 wherein each of the sets is substantially identical.
Claim 7
Dependent Claim
48 words
An electrical circuit breaking system which comprises (1) a circuit breaker, and (2) a device assembly which is connected in series with the circuit breaker and which comprises at least five PTC elements which (a) are connected in series, (b) have been manufactured by the same process, and
Claim 8
Dependent Claim
48 words
An electrical circuit breaking system which comprises (1) a circuit breaker, and (2) a device assembly which is connected in series with the circuit breaker and which comprises at least five PTC elements which (a) are connected in series, (b) have been manufactured by the same process, and
Claim 9
Dependent Claim
30 words
A system according to claim 5 wherein each of the PTC elements is composed of a material which exhibits PTC behavior with an R 30 value of 100 to 10,000.
Claim 10
Dependent Claim
17 words
A system according to claim 5 wherein the PTC element is composed of a conductive polymer composition.
Claim 11
Dependent Claim
128 words
An electrical switching system which has a closed configuration, an intermediate configuration, and an open configuration, and which comprises (1) a first metal contact surface, (2) a second metal contact surface, and (3) a device assembly which comprises at least three PTC elements which (a) are connected in series, and (b) have been made by the same manufacturing process, the first and second surfaces being in direct physical contact when the system is in the closed configuration; the first and second surfaces being physically separated from each other but electrically connected to each other through the device assembly when the system is in the intermediate configuration; and the first and second surfaces being physically and electrically separated from each other when the system is in the open configuration.
Claim 12
Dependent Claim
128 words
An electrical switching system which has a closed configuration, an intermediate configuration, and an open configuration, and which comprises (1) a first metal contact surface, (2) a second metal contact surface, and (3) a device assembly which comprises at least three PTC elements which (a) are connected in series, and (b) have been made by the same manufacturing process, the first and second surfaces being in direct physical contact when the system is in the closed configuration; the first and second surfaces being physically separated from each other but electrically connected to each other through the device assembly when the system is in the intermediate configuration; and the first and second surfaces being physically and electrically separated from each other when the system is in the open configuration.
Claim 13
Dependent Claim
18 words
A system according to claim 8 wherein each of the PTC elements is composed of a conductive polymer.
References Cited (Backward Citations)
DE2331708A1
Cited
US4177376A
Cited
US4017715A
Cited
US4421582A
Cited
US4246468A
Cited
US4329726A
Cited
US4346424A
Cited
FR2506067A1
Cited
US4574188A
Cited
US4764663A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-10-29 | 1994-04-30 | 1994-10-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-10-29 | 1998-04-30 | 1998-10-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-10-29 | 2002-04-30 | 2002-10-30 | $7700.00 | Window Closed / Lapsed |