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Joseph O. Thorsheim

(1906 - 1986) His career was a mixture of music, teaching, inventing and consulting. He was known for originality and innovation in creatively solving mechanical and electro-mechanical problems. Safety considerations were essential factors in most of his projects because they concerned control or high temperature, flammable liquids, explosive materials, and other environmental hazards. Thorsheim was the creator of 18 patented inventions assigned to Honeywell and countless other inventions that were not patented because of government security policies.

Honeywell physicist and engineer, he invented the first effective hydrogen-oxygen fuel cell control, and an auto exhaust analyzer that was cited as one of the most significant inventions of 1970. In 1962/63, he received patents on the Celmaster™ - the automatic fuel cell pressure control - a revolutionary idea to provide power for diverse needs such as homes, industry, transportation, and auxiliary power for space travel vehicles. In 1970/71, his pioneering invention of the automobile exhaust analyzer, designed to combat air pollution, was put into use by the Ford Motor Company.


He originated countless ideas for monitoring and control devices which continue to improve society's comfort, health and security, as well as generate business and employment for Minnesotans.

Fuel cells have played a key role in the space program including the Apollo flights to the moon, and Thorsheim’s work played a key role in successful fuel cell design and control. Fuel cells can produce electricity and water at high efficiency when provided with hydrogen and oxygen. Being reversible, fuel cells can also produce hydrogen and oxygen when provided electricity and water. Thus, fuel cells, in one or the other mode, are capable of providing three of the key resources for space flight: electrical power, water to drink, and oxygen to breath. The difficult task which Thorsheim addressed was to control the pressures of the two gasses so that maximum efficiency was obtained, and so that the membrane between the two gases – where the catalytic process takes place – would not be exposed to potentially membrane-rupturing gas differential gas pressures between the gases which would destroy the fuel cell, and place anything and anyone in the environment in danger. He invented a special control used to monitor gas flows into fuel cells for the production of electric power. His work led to an important control device for this space age technology.

The auto exhaust analyzer was especially important in early efforts to reduce air pollution cause by automobile engines. The device measures the proportion of unburned hydrocarbons and carbon dioxide in a car’s exhaust gases. Shop equipment fitted with this analyzer was sold by Ford Motor Company to its dealers so they could determine when a tune-up was needed to reduce air pollution. This analyzer could also burn an exhaust gas sample to determine the amount of unburned gasoline, thereby contributing to energy savings. In 1970 - Industrial Research selected his invention of the automobile exhaust analyzer as one of the one hundred significant developments in America.

In 1962, Thorsheim invented and developed the first effective fuel cell control developed for use in the then fledgling commercial fuel cell market (Honeywell World, August 6, 1962). The fuel cell was a revolutionary continuous-feed battery which produced electrical power directly from fuel (hydrogen-oxygen) through a chemical reaction. Electrical power is produced by the fuel cell without any smoke, noise, noxious fumes or vibration. Moreover, it has an efficiency of up to 7o percent compared to 35 percent for a steam turbine, or 15 percent for an automobile. Uses of fuel cell are many and varied: from providing power for boats to locomotives, auxiliary power for space vehicles, to producing power for homes and industry. The controller for the fuel cell is used in the space program. "I was pretty proud when it was on the moon," he said.

A long time scientist for Honeywell who invented everything from a fuel cell used in space to reflective body bands for bicyclists and joggers. His inventions have achieve the highest goal in preventive medicine: to prevent respiratory illness in millions and actually prevent respiratory death in thousands if not millions.

Other aspects of his work deserve mentions: his work on degree-days in determining the optimum time to harvest peas and corn in Minnesota; his work on devices to simplify and expedite work in home kitchens; his work on Glo-Jo to improve safety for night bicycle riders or hikers. He also developed reflective safety straps used by student crossing guards, resulting in greater safety for those students performing this very valuable service.

Thorsheim invented special devices such as a degree-day computer designed to monitor the growing cycle of certain plants. This required measurement of the number of hours that plants such as beans were exposed to sunshine above a certain temperature. He invented a clever meter which used two small clocks running together. One clock measured total time while the other measured temperature-time, varying its rate according to temperature. Between the two, degree-day calculations were made. This permitted close control of ripening periods.

Thorsheim also developed a special balanced fluid pressure control which solved the problem of varying water temperatures in mixed temperature systems due to pressure variations. A device to control water temperature in faucets, showers and tubs was constructed and worked very nicely.

Another interesting invention was the degree-day computer Thorsheim invented to monitor the growth cycle of certain plants. This invention involved measuring the number of hours that plants such as beans and peas were exposed to sunshine above a certain temperature. Two clocks were used to run together and function as a clever meter; one clock kept track of total time while the other measured only the time during which the plants received enough energy from the sun to grow. The device is reported to be in use today by the Green Giant Company.

Early transistor development was another area of Thorsheim’s creativity. He worked on the housing designs for transistors and assisted in developing a special impact formed housing which was used in the early mass production versions.

He was a member of Honeywell’s first Corporate Research Unit. Both patented and non-patented ideas received recognition for their major technical contributions to product engineering and design. Honeywell’s military products used some of his sensor and mechanical actuating device concepts. He authored many internal Honeywell papers and memos and contributed many ideas that led to new design solutions for Honeywell’s control, safety, and security systems.

Thorsheim also worked on his own time, with the approval of Honeywell, on everything from a toy submarine to a spice rack.

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