US 3,561,525 — Heat Pipe Condensate Return

Inventor: Stephen C. Baer, Corrales, New Mexico
Assignee: Energy Conversion Systems, Inc. (Albuquerque, NM)
Filed: July 2, 1969
Granted: February 9, 1971
Status: Expired — Lifetime
Note: Assigned to Energy Conversion Systems, Inc. — not Zomeworks. This is an early Baer patent predating Zomeworks (founded 1969).

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Abstract

Improved condensate return system for evaporation-condensation heat exchangers using osmotic action. Traditional heat pipes use capillary wicks limited to 1–4 feet of lift, weakened by gravity. This device inserts a semipermeable membrane (cellulose) at the liquid-vapor interface; osmotic pressure pumps condensed vapor back to the heat source more effectively than capillary action and independent of gravitational forces.

Key claim

A hermetically sealed heat-conducting container with a solution return channel, vapor passage, and semipermeable membrane positioned to allow osmotic pressure to pump condensed vapor back to the heat source.

Significance

• Baer’s earliest known patent — filed July 1969, the same year he co-founded Zomeworks
• Shows Baer working on heat transfer problems (osmotic pumping) at the same time as the geometric/zome work
• Cited by Hughes Aircraft osmotic heat pipe patents (1979–1982) and modern cooling applications through 2025 — influence extended well beyond passive solar
• Assigned to Energy Conversion Systems, not Zomeworks — suggests Baer had a separate commercial vehicle for engineering work

See also

• Steve Baer
• Zomeworks Corporation
• Thermosiphon