US 3,618,569 — Device for Transferring Heat in Water Reservoir

Inventor: Stephen C. Baer, Corrales, New Mexico
Assignee: Individual (Baer personally)
Filed: July 17, 1969
Granted: November 9, 1971
Status: Expired — Lifetime
Common name: “Stock Pond Melter” (steve-baer.md)

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Abstract

Prevents ice formation on livestock water tanks using a sealed convection loop filled with volatile liquid. Two enlarged ends connected by insulated straight sections exploit water’s density anomaly (maximum density at 4°C): warmer bottom water transfers heat to the cold surface via the convection loop, preventing ice without electricity.

Key claim

A sealed hollow tube loop with two enlarged ends connected by insulated tube portions, filled with heat-transfer fluid (e.g., alcohol), creating convection current from warmer deep water to freezing surface.

Significance

• Baer’s second known patent, filed the same day as US 3,561,525 (July 17, 1969) — but assigned personally rather than to a company
• The passive convection loop is the same density-driven principle as the thermosiphon — Baer had understood this mechanism at least since 1969
• Cited by 13 subsequent patents including heat pipe de-icing (1981) and solar-heated stock tanks (1978)
• Practical, low-tech application: zero electricity, no moving parts, exploits physics

See also

• Steve Baer
• Thermosiphon
• Zomeworks Corporation