US3748439A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heating apparatus
Assignee: Texas Instruments Inc
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Filing: 1971-12-27
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Granted: 1973-07-24
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Expires: 1991-12-27
Abstract
Abstract A heater assembly is disclosed comprising a flat mass of positive temperature coefficient of resistivity material attached to a first heat sink plate which extends beyond the flat mass in length and width. The flat mass has a flame sprayed layer of aluminum on opposite sides, a second flame sprayed layer of copper on at least one opposite side to permit attachment of a terminal, and the other opposite side being attached to the heat sink plate by electrically and thermally conductive solder or epoxy material. The flat mass and plate in one embodiment is received in a shrinkable electrically insulative sleeve and in another embodiment in a thermally conductive can, both the sleeve and can being sealed so that the assembly can be immersed in fluid for heating thereof. The heaters of both embodiments are received in a pocket formed in a second heat sink formed of elongated flexible foil having pressure sensitive adhesive on one surface to facilitate attachment of the assembly to a surface to be heated.
Inventors
- 👤 Y Ting
- 👤 L Marcoux
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 16:55
CPC Classifications
H; H01; H01C; H01C1/00; H01C1/14; H01C1/1406; H01C1/08; H01C1/084; H05; H05B; H05B3/00; H05B3/10; H05B3/12; H05B3/14; H05B3/141
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
123 words
A self-regulating heating device comprising: an element composed of ceramic type material having a steeply sloped positive temperature coefficient of resistance, the element having first and second surfaces spaced from each other; the first surface having a layer of aluminum bonded thereto and forming an ohmic contact therewith and a solderable layer of copper bonded to the aluminum layer; the second surface having a layer of aluminum bonded thereto and forming an ohmic contact therewith; a first heat sink comprising a plate of thermally conductive material; a first terminal means attached to the heat sink; a second terminal means soldered to the copper layer; and electrically and thermally conductive epoxy bonding the aluminum layer on the second surface to the heat sink plate.
Claim 2
Dependent Claim
123 words
A self-regulating heating device comprising: an element composed of ceramic type material having a steeply sloped positive temperature coefficient of resistance, the element having first and second surfaces spaced from each other; the first surface having a layer of aluminum bonded thereto and forming an ohmic contact therewith and a solderable layer of copper bonded to the aluminum layer; the second surface having a layer of aluminum bonded thereto and forming an ohmic contact therewith; a first heat sink comprising a plate of thermally conductive material; a first terminal means attached to the heat sink; a second terminal means soldered to the copper layer; and electrically and thermally conductive epoxy bonding the aluminum layer on the second surface to the heat sink plate.
Claim 3
Dependent Claim
25 words
A self-regulating heating device as set forth in claim 1 in which the first heat sink plate extends beyond the element in length and width.
Claim 4
Dependent Claim
132 words
A self-regulating heating device as set forth in claim 2 including at least one additional element composed of ceramic type material having a steeply sloped positive temperature coefficient of resistance, the additional element havine first and second surfaces spaced from each other; the first surface of the additional element having a layer of aluminum bonded thereto and forming an ohmic contact therewith an a solderable layer of copper bonded to the aluminum layer; the second surface of the additional element having a layer of aluminum bonded thereto and forming an ohmic contact therewith; electrically and thermally conductive epoxy bonding the aluminum layer on the second surface of the additional element to the heat sink plate; and an electrical conductor soldered to respective copper layers to connect the elements in parallel circuit relationship.
Claim 5
Dependent Claim
91 words
A heater assembly comprising: electrical resistor means including at least one element composed of ceramic type material; first heat sink means including a thermally conductive plate, the electrical resistor means attached to the plate; second heat sink means comprising an eloNgated flexible foil member formed with a pocket therein, the foil member extending substantially beyond the pocket, the electrical resistor means and the first heat sink means received within the pocket; and means to electrically separate the electrical resistor means and first heat sink means from the second heat sink means.
Claim 6
Dependent Claim
91 words
A heater assembly comprising: electrical resistor means including at least one element composed of ceramic type material; first heat sink means including a thermally conductive plate, the electrical resistor means attached to the plate; second heat sink means comprising an eloNgated flexible foil member formed with a pocket therein, the foil member extending substantially beyond the pocket, the electrical resistor means and the first heat sink means received within the pocket; and means to electrically separate the electrical resistor means and first heat sink means from the second heat sink means.
Claim 7
Dependent Claim
33 words
A heater assembly according to claim 4 including a layer of pressure sensitive adhesive on a surface of the foil to facilitate attachment of the heating assembly to a surface to be heated.
Claim 8
Dependent Claim
30 words
A heater assembly as set forth in claim 4 in which the electrical resistor means has a steeply sloped positive temperature coefficient of resistivity whereby the heater assembly is self-regulating.
Claim 9
Dependent Claim
24 words
A heater assembly as set forth in claim 6 in which the electrical resistor means includes an element composed of a doped barium titanate.
Claim 10
Dependent Claim
73 words
A heater assembly as set forth in claim 7 in which the doped barium titanate is in the form of a flat mass having first and second surfaces, a flame sprayed layer of aluminum on the first and second surfaces of the flat mass, a flame sprayed layer of copper on the aluminum layer on the first surface, and means electrically and thermally attaching the second surface to the first heat sink plate.
Claim 11
Dependent Claim
89 words
A heat assembly as set forth in claim 8 including a first terminal wire attached to the first heat sink plate, a second terminal wire attached to the copper layer on the element, a shrinkable electrically insulative sleeve telescopically receiving and shrunk about the heater assembly therein, the sleeve having an end which is closed by heat sealing and a second end through which the terminal wires extend, the second end sealed by electrically insulative potting material whereby the assembly can be inserted into fluid material for heating thereof.
Claim 12
Dependent Claim
113 words
A heater assembly as set forth in claim 8 including a first terminal wire attached to the first heat sink plate, a second terminal wire attached to the copper layer on the element, a can of thermally conductive material having a closed end, depending walls and an open end, a sheet of electrically insulative and thermally conductive material with pressure sensitive adhesive on opposite sides thereof placed in the can on a depending wall portion, the heater assembly received in the can, the first heat sink plate having a surface opposite to that on which the element is mounted in contact with the sheet and electrically insulative potting compound sealingly filling the can.
Claim 13
Dependent Claim
24 words
A heater assembly according to claim 4 in which the electrical resistor means includes at least two resistor elements connected in parallel circuit relationship.
Claim 14
Dependent Claim
84 words
A heat assembly as set forth in claim 4 including a first terminal wire attached to the first heat sink plate, a second terminal wire attached to the resistor means, a shrinkable electrically insulative sleeve telescopically receiving and shrunk about the heater assembly therein, the sleeve having an end which is closed by heat sealing and a second end through which the terminal wires extend, the second end sealed by electrically insulative potting material to prevent entry of liquids and moisture into the assembly.
Claim 15
Dependent Claim
107 words
A heater assembly as set forth in claim 4 including a first terminal wire attached to the first heat sink plate, a second terminal wire attached to the resistor means, a can of thermally conductive material having a closed end, depending walls and an open end, a sheet of thermally conductive material with pressure sensitive adhesive on opposite sides thereof placed in the can on a depending wall portion, the heater assembly received in the can, the first heat sink plate having a surface opposite to that on which the element is mounted in contact with the sheet and electrically insulative potting compound sealingly filling the can.
Claim 16
Dependent Claim
49 words
A heater assembly according to claim 4 in which the foil member includes a top and bottom sheet, a layer of adhesive is provided on the same side of each sheet whereby the sheets are fastened together and the assembly can be fastened to an object to be heated.
Claim 17
Dependent Claim
44 words
A heater assembly according to claim 4 in which the foil member extends beyond the pocket in at least two directions forming flexible wings extending from the first heat sink means to facilitate attachment in close heat transfer relationship to surfaces of various configurations.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-07-23 | 1977-01-22 | 1977-07-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-23 | 1981-01-22 | 1981-07-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-23 | 1985-01-22 | 1985-07-24 | $7700.00 | Window Closed / Lapsed |