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AssigneeGeorgina Chrystall Hirtle
InventorFrank T. John
Estimating the term…
It has been discovered that electrically conducting, vitreous pyrolytic carbon in broken-bubble, foam-type, reticulated structures can be used as an extremely fast and efficient electrically operated motor to actuate mechanical devices, such as mercury liquid contact relays, by electrothermally-produced gas expansion. The gas pressure change is produced evenly and almost instantaneously throughout the volume of the reticular motor to move mercury contacts, to open or close a liquid contact relay, thus avoiding the expensive electromagnetic coils now used as relay motors. By passing an electrical current through conducting reticulated material formed from pyrolytic carbon, metals, conductive ceramics or plastics, the microscopic network of interconnecting filaments is heated, thus heating and expanding the fluid (air, hydrogen, helium, argon, etc.) contained in the reticular motor. The time required to operate the device depends on the thermal gradient and the square of the average thermal diffusion distance between the gas and the nearest heating filament. Since the diffusion distance is very small, the device is very fast and efficient. For fast repetative motor operation, a reticulated material of high thermal conductivity such as silver, silicon nitride, or boron nitride, is sealed to the inside walls of the motor. The reticular electrothermal motor is useful for operating mechanical devices including both miniature logic relays and large industrial relays. The high power requirement of the latter may be supplied by using change of state expansion of volatilizable liquids such as are used as refrigerants or as propellants in aerosol spray containers.
A liquid contact relay which comprises a body of solid material containing gas in a multiplicity of intercommunicating volumes therein, which body is of a sufficient resistance to the flow of electricity so that as electricity is passed through it the material thereof is heated and readily transfers heat to the gas contained therein so as to heat and expand such gas, an electrically conductive liquid which alternately completes and opens a relay circuit in different positions of such liquid, and means for operatively connecting the expandable gas of the body with the conductive liquid so that when electricity is passed through the material the gas therein is expanded and such expansion causes movement of the liquid to change the relay circuit to open or closed state from its previous condition.
A motor, useful for activating a liquid contact relay, which comprises a body of electrically conductive solid material containing gas in a multiplicity of intercommunicating volumes therein, which body is of sufficient resistance to the flow of electricity so that as electricity is passed through it the material thereof is heated, and readily transfers heat to the gas contained therein so as to heat and expand such gas, and means for transmitting pressure developed by the expansion of such gas so that such pressure may effect movement of a relay component or other means in response to the flow of electricity through the body of solid material and to the gas pressure thereby produced.
A method of controlling a second electrical circuit in response to electrical flow in a first circuit which comprises passing electricity through said first circuit and through a solid body of material therein which contains gas in a multiplicity of intercommunicating volumes therein, which body is conductive of electricity and of a sufficient resistance to the flow thereof that as electricity is passed through it the material of the body is heated and transfers heat to the gas contained therein so as to heat and expand such gas and develop a pressure, and communicating such pressure to pressure responsive means in such second circuit for opening or closing such circuit.
A method of applying pressure to an object or material in response to the passage of electricity through means separate from such material or object which comprises passing electricity through an electrical circuit and through a solid body of material therein, which material contains gas in a multiplicity of intercommunicating volumes therein and which is conductive of electricity and of sufficient resistance to the flow thereof that as electricity is passed through it the material of the body is heated and transfers heat to the gas contained therein so as to heat and expand such gas, containing the heated and expanded gas in a container located about the body and transmitting the pressure developed in such container to said separate object or material.
A motor, useful for activating a liquid contact relay, which comprises a body of electrically conductive solid material containing a volatilizable liquid in a multiplicity of intercommunicating volumes therein, which body is of sufficient resistance to the flow of electricity so that as electricity is passed through it the material thereof is heated and readily transfers heat to the volatilizable liquid contained therein so as to heat such liquid and convert at least a part thereof to a gas, and means for transmitting pressure developed by the change of state of the liquid to a gas so that such pressure may effect movement of a relay component or other means in response to the flow of electricity through the body of solid material and in response to the gas pressure thereby produced.
A liquid contact relay which comprises a body of solid material containing a volatilizable liquid in a multiplicity of intercommunicating volumes therein, which body is of a sufficient resistance to the flow of electricity so that as the electricity is passed through it the material thereof is heated and readily transfers heat to the volatilizable liquid contained therein so as to vaporize such liquid, an electrically conductive liquid which alternately completes and opens a relay circuit in different positions of such liquid, and means for operatively connecting the gas resulting from such change of state, due to heating of the volatilizable liquid, with the conductive liquid so that when electricity is passed through the material the gas so produced causes movement of the conductive liquid to change the relay circuit to open or closed position from its previous position.
A liquid contact relay which comprises a body of solid material containing gas in a multiplicity of intercommunicating volumes therein, which body is of a sufficient resistance to the flow of electricity so that as electricity is passed through it the material thereof is heated and readily transfers heat to the gas contained therein so as to heat and expand such gas, an electrically conductive liquid which alternately opens and completes a relay circuit in different positions of such liquid, and means for operatively connecting the expandable gas of the body with the conductive liquid so that when electricity is passed through the material the gas therein holds a relay in open or closed state and when such flow of electricity is interrupted the gas contracts and causes movement of the liquid to change the relay circuit to a different closed or opened state from its previous condition.
An electrothermal relay comprising at least one electrical contact connected to and controlling a controlled electrical circuit, an enclosure, with external heat exchange means, a heating element in said enclosure and containing interconnected microscopically sized heating element components which are electrically conductive and resistive, a fluid filling said enclosure in space between said heater element components, means connecting said fluid to said contact, said heating elements being so interconnected and dispersed throughout said enclosure so that essentially all of said fluid is within a microscopic distance of such a heating element component, means for applying an electrical voltage difference of a controlling circuit to said heating element, to cause by electrical heating effect a thermally induced pressure increase in said fluid, thereby causing said fluid to flow and actuating said electrical contact, said heating elements being so relatively small compared to the size of the void volume between said heater elements that the impedance to flow of said fluid is essentially nil, enabling the speeds of response of fluid flow and contact movement in the control circuit to respond rapidly and accurately follow controlling circuit stimuli.
An electrothermal relay comprising at least one electrical contact connected to at least one controlled circuit, whereby the movement of said contact opens and closes the controlled circuit, an enclosure with an external heat exchanger, which enclosure contains a heating element with parts thereof of microscopic size and interconnected, which is electrically conductive and resistive, and structurally self supporting, a fluid in said enclosure located in the spacing between said heating elements, means for transmitting an electrical controlling voltage difference of a controlling circuit to said heating element, which causes, by electrical heat effect, the generation of thermally induced pressure and flow in said fluid, means connecting said fluid to said contact, said heating element being of such a size and separation that said fluid maintains a constant temperature throughout said enclosure in a convection-free manner, and said contacts move as a result of fluid flow and pressure transmission in such a manner as to faithfully follow pressure changes in the enclosure in a close time relationship.
Dependencies are inferred from the claim text.