← Back to Patent Explorer
US5436609A Expired / Lapsed US ⏱️ 0.0 years remaining

Electrical device

Assignee: Tyco International Ltd Bermuda
•
Filing: 1993-07-06
•
Granted: 1995-07-25
•
Expires: 2013-07-06
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract An electrical device in which a conductive terminal is physically and electrically attached directly or indirectly to a face of a laminar PTC resistive element. The terminal comprises a laminar portion and a non-laminar shaped portion which lies within a projection of the periphery of the PTC resistive element. The shaped portion serves to improve thermal transfer between the PTC element and the atmosphere surrounding the device. Devices of the invention are useful as circuit protection devices.

Inventors

  • 👤 Chi-Ming Chan
  • 👤 Shou-Mean Fang

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 15:18
CPC Classifications
H; H01; H01C; H01C1/00; H01C1/14; H01C1/1406

Claims Analysis

Total Claims: 24
Claim 1
Independent Claim 108 words
A circuit protection device which comprises (1) a laminar resistive PTC element which has a resistance at 23° C. of 0.001 to 100 ohms and which (a) is composed of a PTC conductive polymer which has a resistivity at 23° C. of 0.01 to 100 Ohm-cm, and (b) has a first periphery; and (2) a conductive terminal comprising (a) a laminar portion which is secured directly or indirectly to a first face of the resistive PTC element, and (b) a non-laminar shaped portion which (i) lies within a projection of the first periphery and (ii) improves thermal transfer between the PTC element and the atmosphere surrounding the device.
Claim 2
Dependent Claim 108 words
A circuit protection device which comprises (1) a laminar resistive PTC element which has a resistance at 23° C. of 0.001 to 100 ohms and which (a) is composed of a PTC conductive polymer which has a resistivity at 23° C. of 0.01 to 100 Ohm-cm, and (b) has a first periphery; and (2) a conductive terminal comprising (a) a laminar portion which is secured directly or indirectly to a first face of the resistive PTC element, and (b) a non-laminar shaped portion which (i) lies within a projection of the first periphery and (ii) improves thermal transfer between the PTC element and the atmosphere surrounding the device.
Claim 3
Dependent Claim 30 words
A device according to claim 1 which includes a second terminal which comprises a laminar portion which is secured directly or indirectly to the opposite face of the PTC element.
Claim 4
Dependent Claim 41 words
A device according to claim 2 wherein the second terminal comprises a non-laminar shaped portion which (i) lies within a projection of the first periphery and (ii) further improves thermal transfer between the PTC element and the atmosphere surrounding the device.
Claim 5
Dependent Claim 37 words
A device according to claim 1 wherein the surface area of the shaped portion of the terminal exposed to the atmosphere is at least 1.5 times the area of the laminar portion secured to the PTC element.
Claim 6
Dependent Claim 37 words
A device according to claim 4 wherein the surface area of the shaped portion of the terminal exposed to the atmosphere is at least 2 times the area of the laminar portion secured to the PTC element.
Claim 7
Dependent Claim 37 words
A device according to claim 5 wherein the surface area of the shaped portion of the terminal exposed to the atmosphere is at least 4 times the area of the laminar portion secured to the PTC element.
Claim 8
Dependent Claim 28 words
A device according to claim 1 wherein the non-laminar shaped portion comprises at least one fin which extends outwards away from the PTC element within the periphery thereof.
Claim 9
Dependent Claim 26 words
A device according to claim 7 wherein there are at least two fins and the fins are connected to each other only by the laminar portion.
Claim 10
Dependent Claim 115 words
A circuit protection device which comprises (1) a laminar resistive PTC element which (a) is composed of a PTC conductive polymer, and (b) has a first periphery; and (2) a conductive terminal comprising (a) a laminar portion which is secured directly or indirectly to a first face of the resistive PTC element, and (b) a non-laminar shaped portion which (i) lies within a projection of the first periphery, (ii) improves thermal transfer between the PTC element and the atmosphere surrounding the device, and (iii) comprises at least two fins which extend outwards away from the PTC element within the periphery thereof and at least two fins which are connected to each other by a cross-member.
Claim 11
Dependent Claim 115 words
A circuit protection device which comprises (1) a laminar resistive PTC element which (a) is composed of a PTC conductive polymer, and (b) has a first periphery; and (2) a conductive terminal comprising (a) a laminar portion which is secured directly or indirectly to a first face of the resistive PTC element, and (b) a non-laminar shaped portion which (i) lies within a projection of the first periphery, (ii) improves thermal transfer between the PTC element and the atmosphere surrounding the device, and (iii) comprises at least two fins which extend outwards away from the PTC element within the periphery thereof and at least two fins which are connected to each other by a cross-member.
Claim 12
Dependent Claim 37 words
A device according to claim 1 which includes a laminar conductive element which (a) is secured to a face of the resistive element, and (b) has a second periphery which does not extend beyond the first periphery.
Claim 13
Dependent Claim 12 words
A device according to claim 10 wherein the conductive element comprises solder.
Claim 14
Dependent Claim 39 words
A device according to claim 10 which includes a laminar electrode which (a) lies between the resistive element and the conductive element and is secured to the resistive element and the conductive element, and (b) has a fourth periphery.
Claim 15
Dependent Claim 15 words
A device according to claim 12 wherein the laminar electrode is a metal foil electrode.
Claim 16
Dependent Claim 24 words
A device according to claim 13 wherein the laminar electrode has an electrodeposited metal surface, which surface is in contact with the resistive element.
Claim 17
Dependent Claim 123 words
An assembly which comprises (A) a circuit protection device which comprises (1) a laminar resistive PTC element which has a resistance at 23° C. of 0.001 to 100 ohms and which (a) is composed of a PTC conductive polymer which has a resistivity at 23° C. of 0.01 to 100 ohm-cm, and (b) has a first periphery; and (2) a conductive terminal comprising (a) a laminar portion which is secured directly or indirectly to a first face of the resistive PTC element, and (b) a non-laminar shaped portion which (i) lies within a projection of the first periphery and (ii) improves thermal transfer between the PTC element and the atmosphere surrounding the device, and (B) a substrate to which the device is attached.
Claim 18
Dependent Claim 123 words
An assembly which comprises (A) a circuit protection device which comprises (1) a laminar resistive PTC element which has a resistance at 23° C. of 0.001 to 100 ohms and which (a) is composed of a PTC conductive polymer which has a resistivity at 23° C. of 0.01 to 100 ohm-cm, and (b) has a first periphery; and (2) a conductive terminal comprising (a) a laminar portion which is secured directly or indirectly to a first face of the resistive PTC element, and (b) a non-laminar shaped portion which (i) lies within a projection of the first periphery and (ii) improves thermal transfer between the PTC element and the atmosphere surrounding the device, and (B) a substrate to which the device is attached.
Claim 19
Dependent Claim 51 words
An assembly according to claim 15 wherein (a) the substrate is substantially horizontal, and (b) the plane of the PTC resistive element is substantially parallel to the substrate and the shaped portion of the terminal comprises fins which extend from the face of the PTC resistive element remote from the substrate.
Claim 20
Dependent Claim 33 words
An assembly according to claim 15 wherein (a) the substrate is substantially horizontal, and (b) the plane of the PTC resistive element is substantially at right angles to the plane of the substrate.
Claim 21
Dependent Claim 12 words
An assembly according to claim 15 wherein the substrate is substantially vertical.
Claim 22
Dependent Claim 123 words
A circuit which comprises (A) a circuit protection device which comprises (1) a laminar resistive PTC element which has a resistance at 23° C. of 0.001 to 100 ohms and which (a) is composed of a PTC conductive polymer which has a resistivity at 23° C. of 0.01 to 100 ohm-cm, and (b) has a first periphery; and (2) a conductive terminal comprising (a) a laminar portion which is secured directly or indirectly to a first face of the resistive PTC element, and (b) a non-laminar shaped portion which (i) lies within a projection of the first periphery and (ii) improves thermal transfer between the PTC element and the atmosphere surrounding the device, and (B) a power source, and (C) and electrical load.
Claim 23
Dependent Claim 123 words
A circuit which comprises (A) a circuit protection device which comprises (1) a laminar resistive PTC element which has a resistance at 23° C. of 0.001 to 100 ohms and which (a) is composed of a PTC conductive polymer which has a resistivity at 23° C. of 0.01 to 100 ohm-cm, and (b) has a first periphery; and (2) a conductive terminal comprising (a) a laminar portion which is secured directly or indirectly to a first face of the resistive PTC element, and (b) a non-laminar shaped portion which (i) lies within a projection of the first periphery and (ii) improves thermal transfer between the PTC element and the atmosphere surrounding the device, and (B) a power source, and (C) and electrical load.
Claim 24
Dependent Claim 43 words
A circuit according to claim 19 wherein the non-laminar shaped portion of the circuit protection device comprises at least two fins which extend outwards away from the PTC element within the periphery thereof and which are connected to each other by a cross-member.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1998-07-24 1999-01-23 1999-07-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2002-07-24 2003-01-23 2003-07-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2006-07-24 2007-01-23 2007-07-25 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag