US3746836A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Aquarium heater
Assignee: Mattel Inc
•
Filing: 1971-12-15
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Granted: 1973-07-17
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Expires: 1991-12-15
Abstract
Abstract An aquarium heater comprising a housing, or heater tube, in which is provided heating coils for heating the housing to a temperature higher than ambient temperature. Extending in the housing is an appropriate electral circuit for providing electrical current to the heating coils. A pair of independently actuable thermostats are operatively associated with the eletrical circuit, each for independently opening and closing the circuit selectively in response to respective external termperature levels, one of which is a safety switch for preventing the heater tube from overheating.
Inventors
- 👤 W Summerfield
- 👤 F Nuttall
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 21:12
CPC Classifications
H; H05; H05B; H05B1/00; H05B1/02; H05B1/0202; H05B1/0213; A; A01; A01K; A01K63/00; A01K63/06; A01K63/065; H05B3/00; H05B3/78; H05B3/80
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
204 words
An aquarium heater comprising a housing, said housing being constituted at least in part of heat conductive material, electrical heating means extending in said housing for heating said housing to a temperature higher than ambient temperature, circuit means extending in said housing for supplying electrical current to said electrical heating means, and a pair of independently actuable thermostats operatively associated with said circuit means each for independently opening and closing said circuit means selectively in response to respective external temperature levels, one of said thermostats being responsive to a temperature level of a selected medium to be heated, the other of said thermostats being responsive to a temperature level higher than for said one thermostat and corresponding to a hazardous temperature of the housing which approaches the temperature of the heating means, the other of said thermostats including a bimetallic switching member in close proximity with said heating means, a heat conductive core extending in said housing and at least partially contacting said housing, said heating means including a heating element extending along said core, said bimetallic switching member including a fixed end portion connected to said core and a free end portion movable into and out of operative association with said circuit means.
Claim 2
Dependent Claim
204 words
An aquarium heater comprising a housing, said housing being constituted at least in part of heat conductive material, electrical heating means extending in said housing for heating said housing to a temperature higher than ambient temperature, circuit means extending in said housing for supplying electrical current to said electrical heating means, and a pair of independently actuable thermostats operatively associated with said circuit means each for independently opening and closing said circuit means selectively in response to respective external temperature levels, one of said thermostats being responsive to a temperature level of a selected medium to be heated, the other of said thermostats being responsive to a temperature level higher than for said one thermostat and corresponding to a hazardous temperature of the housing which approaches the temperature of the heating means, the other of said thermostats including a bimetallic switching member in close proximity with said heating means, a heat conductive core extending in said housing and at least partially contacting said housing, said heating means including a heating element extending along said core, said bimetallic switching member including a fixed end portion connected to said core and a free end portion movable into and out of operative association with said circuit means.
Claim 3
Dependent Claim
15 words
An aquarium heater as claimed in claim 1 wherein said heat conductive material is metallic.
Claim 4
Dependent Claim
23 words
An aquarium heater as claimed in claim 1 wherein said housing includes means for completely sealing tHe interior thereof against fluid penetration thereinto.
Claim 5
Dependent Claim
16 words
An aquarium heater as claimed in claim 1 wherein the one of said thermostats is adjustable.
Claim 6
Dependent Claim
31 words
An aquarium heater as claimed in claim 4 wherein the other of said thermostats is operative for opening said circuit means at a greater external temperature than for the adjustable thermostat.
Claim 7
Dependent Claim
52 words
An aquarium heater as claimed in claim 4 wherein the other of said thermostats is constituted as a safety thermostat, said adjustable thermostat being remotely spaced from said heating means and, thereby, less sensitive to a temperature difference between said heating means and the exterior of the housing than said safety thermostat.
Claim 8
Dependent Claim
138 words
An aquarium heater comprising a housing, said housing being at least partially metallic, electrical heating means extending in said housing for heating said housing to a temperature greater than ambient temperature, circuit means extending in said housing for supplying electrical current to said electrical heating means, a thermostat operatively associated with said circuit means for selectively opening and closing said circuit means in response to external temperature levels, said thermostat including a bimetallic switching member in close proximity with said heating means, a metallic core extending in said housing and at least partially contacting said housing, said heating means including a heating coil extending along said metallic core, said bimetallic switching member including a fixed end portion connected to said metallic core and a free end portion movable into and out of operative association with said circuit means.
Claim 9
Dependent Claim
138 words
An aquarium heater comprising a housing, said housing being at least partially metallic, electrical heating means extending in said housing for heating said housing to a temperature greater than ambient temperature, circuit means extending in said housing for supplying electrical current to said electrical heating means, a thermostat operatively associated with said circuit means for selectively opening and closing said circuit means in response to external temperature levels, said thermostat including a bimetallic switching member in close proximity with said heating means, a metallic core extending in said housing and at least partially contacting said housing, said heating means including a heating coil extending along said metallic core, said bimetallic switching member including a fixed end portion connected to said metallic core and a free end portion movable into and out of operative association with said circuit means.
Claim 10
Dependent Claim
48 words
An aquarium heater as claimed in claim 7 wherein said metallic core includes an elongate annular wall provided with elongate parallel troughs spaced relative to one another along the periphery of said annular wall, said heating coil including a plurality of elongate segments seated in said troughs respectively.
Claim 11
Dependent Claim
54 words
An aquarium heater as claimed in claim 8 wherein said annular wall includes a partially slotted portion communicating the exterior of said core with the interior of the latter, the free end of said bimetallic switching member being movable through said slotted portion toward the interior of said core for opening said circuit means.
Claim 12
Dependent Claim
57 words
An aquarium heater as claimed in claim 9 wherein said circuit means includes a partially metallic lever having a movable dielectric free end extending into the interior of said core for being engaged by the free end of said bimetallic switching member, said thermostat including a stationary terminal operatively engageable by a metallic portion of said lever.
Claim 13
Dependent Claim
40 words
An aquarium heater as claimed in claim 10 wherein said circuit means includes a bus-bar at one end of which is disposed said stationary terminal, and a further bimetallic switching member operatively associated with the opposite end of said bus-bar.
Claim 14
Dependent Claim
36 words
An aquarium heater as claimed in claim 11 wherein the opposite end of said bus-bar includes a further stationary terminal adjustable relative to said further bimetallic switching member for being selectively moved relative to the latter.
Claim 15
Dependent Claim
39 words
An aquarium heater as claimed in claim 12 wherein said housing includes a pivotal arm having a free end engageable with the adjustable end of said bus-bar for moving the adjustable end relative to said further bimetallic switching member.
Claim 16
Dependent Claim
34 words
An aquarium heater as claimed in claim 13 wherein said pivotal arm includes an opposite end carrying a light source electrically connected to said circuit means for indicating the energized condition of the latter.
Claim 17
Dependent Claim
50 words
An aquarium heater as claimed in claim 14 wherein said housing includes fluid sealing means for preventing fluid penetration thereinto, said fluid sealing means permitting observation of said light source therethrough, and means for operating said pivotal arm externally of said housing through the intermediary of said fluid sealing means.
Claim 18
Dependent Claim
26 words
An aquarium heater as claimed in claim 15 wherein said fluid sealing means includes a portion which is translucent and a further portion which is deformable.
Claim 19
Dependent Claim
35 words
An aquarium heater as claimed in claim 16 wherein said housing includes an upper plastic portion in which is disposed said sealing means, said plastic portion being constituted of a phenylene oxide resin for durability.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-07-16 | 1977-01-15 | 1977-07-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-16 | 1981-01-15 | 1981-07-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-16 | 1985-01-15 | 1985-07-17 | $7700.00 | Window Closed / Lapsed |