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US3790749A Expired / Lapsed US ⏱️ 0.0 years remaining

Electric lead pot with increased efficiency

Assignee: Individual
•
Filing: 1973-03-26
•
Granted: 1974-02-05
•
Expires: 1993-03-26
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Abstract

Abstract An electrically heated lead melting device includes a thin steel pot disposed within a bright aluminum housing of high reflectivity, with a substantially dead air chamber therebetween. An electric heating coil surrounds the pot within the chamber, with the straight cold ends of the coil passing horizontally into a control box mounted on a base. A single screw and the said coil ends provide the sole support for the pot-housing assembly, which is disposed substantially above the base. The control box may contain suitable temperature regulation mechanism. The construction provides a minimum of contact between the box and base, as well as providing for upward movement of cooling air through the box.

Inventors

  • 👤 R Lee

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-07 08:34
CPC Classifications
A; A47; A47J; A47J27/00; A47J27/004

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 186 words
A lead pot comprising: a. a pot for receiving lead to be melted and having side and bottom walls, b. a housing having side and bottom walls disposed in spaced relation from the respective walls of said pot and forming a chamber therebetween, c. an insulated electric heating coil surrounding said pot in said chamber and with said coil having horizontally disposed straight cold rigid end portions extending through said housing, d. said housing being constructed of a material of high heat reflectivity with a bright inner surface for reflecting heat which has radiated outwardly from said pot back to said pot, e. a base, f. a box having a vertical wall mounted on said base, g. a connector member extending between said housing and said vertical wall, h. means connectively mounting said rigid end portions to said vertical wall, i. said connector memBer and rigid end portions carrying said housing substantially above and free of said base and spaced from said box and providing the sole means for conduction of heat between said pot and said box to thereby substantially isolate them from each other.
Claim 2
Dependent Claim 186 words
A lead pot comprising: a. a pot for receiving lead to be melted and having side and bottom walls, b. a housing having side and bottom walls disposed in spaced relation from the respective walls of said pot and forming a chamber therebetween, c. an insulated electric heating coil surrounding said pot in said chamber and with said coil having horizontally disposed straight cold rigid end portions extending through said housing, d. said housing being constructed of a material of high heat reflectivity with a bright inner surface for reflecting heat which has radiated outwardly from said pot back to said pot, e. a base, f. a box having a vertical wall mounted on said base, g. a connector member extending between said housing and said vertical wall, h. means connectively mounting said rigid end portions to said vertical wall, i. said connector memBer and rigid end portions carrying said housing substantially above and free of said base and spaced from said box and providing the sole means for conduction of heat between said pot and said box to thereby substantially isolate them from each other.
Claim 3
Dependent Claim 47 words
In the lead pot of claim 1, means for substantially reducing heat conduction between said box and said base, said last-named means comprising: a. a plurality of narrow raised ribs on said base, b. said box being mounted transversely across said ribs to provide minimum box-to-base contact.
Claim 4
Dependent Claim 53 words
In the lead pot of claim 1: a. a plurality of raised ribs on said base, b. said box being mounted transversely across said ribs and forming therewith cooling air inlet slot means, c. and vent means in the upper portion of said box for discharging air rising by convection through said box.
Claim 5
Dependent Claim 47 words
In the lead pot of claim 3: a. thermostatic control means for said heating coil and disposed remote from said housing and within said box, b. said control means being only partially responsive to heat received from said lead pot and being cooled by said rising air.

References Cited (Backward Citations)

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US2142852A Cited
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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) 1977-02-04 1977-08-06 1978-02-05 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1981-02-04 1981-08-06 1982-02-05 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1985-02-04 1985-08-06 1986-02-05 $7700.00 Window Closed / Lapsed

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