Introduction
Tesla's inventions and developments include the induction motor, various devices that use rotating magnetic fields, the alternating current polyphase power distribution system, the fundamental devices of systems of wireless communication (legal priority for the invention of radio), radio frequency oscillatorss, devices for voltage magnification by standing waves, robotics, logic gates for secure radio frequency communications, devices for x-rays, devices for ionized gases, devices for high field emission, devices for charged particle beamss, voltage multiplication circuitry, devices for high voltage discharges, devices for lightning protection, the bladeless turbine, and VTOL aircraft
Recent references to Tesla’s patents include US5548819 (Method and apparatus for communication of information), US5908444 (Complex frequency pulsed electromagnetic generator and method of use), and US6104107 (Method and apparatus for single line electrical transmission).
Below are Tesla's known patents:
American
- patent number - name of patent - date - notes on patent
US11865 - Method of Insulating Electric Conductors - 1900 October 23 - Expounding on Faraday's hypothesis of freezing substances make them possess a higher dielectric level; Reissued US655838 patent.
US334823 - Commutator for Dynamo Electric Machines - 1886 January 26 - Elements to prevent sparking on dynamo-electric machines; Drum-style with brushes.
US350954 - Regulator for Dynamo Electric Machines - 1886 October 19 - Automatic regulation of energy levels; Mechanical device to shift brushes.
US335786 - Electric Arc lamp - 1886 February 9 - Arc lamp with carbon electrodes controlled by electromagnets or solenoids and a clutch mechanism; Corrects earlier design flaws common to the industry.
US335787 - Electric arc lamp - 1886 February 9 - Arc lamp's automatic fail switch when arc possesses abnormal behavior; Automatic reactivation.
US336961 - Regulator for dynamo electric machines - 1886 March 2 - Two main brushes connected to helices coil ends; Intermediate point branch shunt connection for third brush.
US336962 - Regulator for Dynamo Electric Machines - 1886 March 2 - Auxiliary brush[es] shunting a portion or whole of the field helices coil; Regulates energy flow; Adjustable level of current.
US359748 - Dynamo electric machine - 1887 March 22 - Improve construction; Facilitate easier construction; Reduce the cost; Magnetic frame; Armature; Alternating current synchronous motor.
US381968 - Electro magnetic motor - 1888 May 1 - Mode and plan of operating electric motors by progressive shifting; Field Magnet; Armature; Electrical conversion; Economical; Transmission of energy; Simple construction; Easier construction; Rotating magnetic field principles.
US381969 - Electro Magnetic Motor - 1888 May 1 - Novel form and operating mode; Coils forming independent energizing circuits; Connected to an alternating current generator; Synchronous motor.
US381970 - System of Electrical Distribution - 1888 May 1 - Current from a single source of supply in the main or transmitting circuit induce by induction apparatus; Independent circuit(s); Electric distributor.
US382279 - Electro Magnetic Motor - 1888 May 1 - Rotation is produced and maintained by direct attraction; Utilizes shifting poles; Induction magnetic motor.
US382280 - Electrical Transmission of Power - 1888 May 1 - New method or mode of transmission; Dynamo motor conversion with two independent circuits for long distance transmission; Alternating current transmission; Includes a disclaimer; Economic; Efficient.
US382281 - Electrical Transmission of Power - 1888 May 1 - Improvements in electromagnetic motors and their mode or methods of their operations; Motor is wound with coils forming independent circuits on the armature; Armature is mounted to rotate in between two different poles; Armature will eventually synchronize with that of the generator; Windcoils or coils on the field magnets; Expose to continuous current to maintain a permanent field.
US382282 - Method of Converting and Distributing Electric Currents - 1888 May 1 - Related to electric distribution systems; Current is from a single main source or suitable transmitting circuit; Induction into an independent circuit; Divide the current from a single source; Transformations; Discovery of method to avoid prior liable and dangerous methods; True Dynamic induction.
US382845 - Commutator for dynamo electric machines - 1888 May 15 - Relates to dynamo-electric machines or motors; Improvements on devices to collect or communicate currents; Avoids destruction and wear of machine; Avoid adjustments due to destruction and wear; Enable practical construction of very large dynamo electric machines or motors with the minimum amount of communicator segments; Increases safety and efficiency.
US390413 - System of electrical distribution - 1888 October 2 - Related to previous electric distribution systems developed by Mr. Tesla; Examples of systems in operations with motors or converters, or both, in parallel; Examples of systems in parallel; Examples of systems in series.
US390414 - Dynamo Electric Machine - 1888 October 2 - Related to the patents of Mr. Tesla and Charles F. Peck, numbers: US381968 and US382280; Ordinary forms of continuous and alternate current systems may be adapted to Mr. Tesla's system, with slight changes to the systems; Effects their forms; Only the best and most practical solutions are presented to the three most common forms of the devices applicable; Illustrated are the continuous (or closed) circuit machines, machines possessing armatures with coils connected diametrically (known as "open-circuits"), and machines with armature-coils of which have a common joint.
US390415 - Dynamo Electric Machine or Motor - 1888 October 2 - Improvement in the construction of dynamo or magneto electric machines; Novel form of frame and field magnets that renders the machine more sturdy and compact as a structure; Requires fewer parts; Less difficulty in construction; Lower expense; Useful to alternating and continuous current machines.
US390721 - Dynamo Electric Machine - 1888 October 9 - Relates chiefly to the alternate current machine invented by Mr. Tesla; Related to patents numbered US381968 and US382280; Seeks to avoid mechanical drawback of running high frequency machines; Efficient at low speeds; Producing rotating magnetic poles in one element of the machine and drive the other at a different speed.
US390820 - Regulator for Alternate Current Motors - 1888 October 9 - Improvement in the electrical transmission systems; Means of regulating and power of the motor or motors; Used with system of multiple motors primarily (or systems with motors and transformers) that have independent energizing circuits which act to set up progressive or shifting magnetic poles (i.e the rotating magnetic field); Controls the speed of the motor.
US396121 - Thermo Magnetic Motor - 1888 January 15 - Widely known that heat applied to a magnetic body will lessen it's magnetizing ability; High enough temperatures will destroy the magnetic field; Mechanical power by a reciprocating action obtained from the joint action of heat, magnetism, and a spring or weight (or other force); In this patent, the application of heats to a body that is magnetized by induction or otherwise to the action of heat until the magnetism is neutralized to allow a weight or a spring to give action and lessen the action of the heat to restore the magnetic effect to move the body in the opposite direction.
US401520 - Method of Operating Electro Magnetic Motors - 1889 April 16 - Improvements to previous instances of synchronous motors; Previous instances of synchronous motors have not been started by the alternating current generators; New discovery of simple method or plan of operating such motors; Requires no other device other than the motor itself; Conversion from a double circuit motor and which will start under the actions of an alternate current into a synchronizing-motor; synchronous motor definition.
US405858 - Electro Magnetic Motor - 1889 June 25 - Torque, instead of being the result in the difference in the magnetic periods or phases of the poless or to the attractive parts to whatever due, is produce to the angular displacement of the parts which, though moveable with the respect to one another, are magnetized simutaneously, or approximately so, by the same currents; Concerns the armature and the field laminations of the magnetic core for the greatest magnetic attractions; Best means to achieve these results.
US405859 - Method of Electrical Power Transmission - 1889 June 25 - New and useful method of bringing up the motor to a desirable speed; Forms of alternating current machines, connected to alternating current generators, can be run as synchronous motor; Prior, alternating current will not start it; Construct a generator with two coils or sets of coils and connect them with a motor of corresponding coils or sets of coils; By means of two line wires, the motor and generator in like fashion; Related to US 390413 (for means of starting); Will operate as a single-circuit synchronizing system.
US406968 - Dynamo Electric Machine - 1889 July 16 - Relates to class of machines referred to as "Unipolar" machine (i.e., a disk or cylindrical conductor is mounted in between magnetic poles adapted to produce a uniform magnetic field); Construction of a machine with two field, each having a rotary conductor mounted between it's poles; Discussed the disk form primarily; The direction of the magnetism or order of the poles in one field of force is opposite to that of the other, so the rotation of the disk in the same direction forms a from the center to the circumference and the other from the circumference to the center; Contact applied to the shafts form terminals of a circuit to produce a sum of electromotive forces of the two disk; If direction of the fields are the same, driving the disks in opposite direction will obtain the same results.
US413353 - Method of Obtaining Direct current from Alternating Currents - 1889 October 22 - Superiority of alternating currents discussed; Delineates machines to convert alternating currents to direct (or continuous) currents at will at one or more points; Obtain direct currents from alternating currents; Active resistances to opposite electrical character, whereby the currents or current-waves of opposite character will be diverted through different circuits.
US416191 - Electro-Magnetic Motor - 1889 December 3 - Induction motor with two or more energizing circuits; alternating currents of differing phases are passed to produce rotation or operation of the motor; simple way consists of two circuits; alternate way consists of one line that divides the alternating current in the motor circuit and effect and artificial lag in one of the circuit of branches (such as by a different induction capacity).
US416192 - Method of Operating Electro-Magnetic Motors - 1889 December 3 - Related to US401520; Alternative improvements to synchronous motors; Torque and synchronous actions in motors; different field circuit of differing induction; Windings and shunts; Increases tendency to synchronize.
US416193 - Electro-Magnetic Motor - 1889 December 3 - Induction motor operation with two or more windings; securing differing phase differences; Phase proportional to the induction and inverse to the resistance encountered by the current; one circuit (the energizing circuit) should have high induction and low resistance (along with possessing the greater length or number of turns) and the converse in the other (which has few turns of finer wire of wire that has higher resistance); magnetic quantities of the poles should be approximately equal; Self-induction cores are much longer.
US416194 - Electric Motor - 1889 December 3 - Drawings include the motor seen in many of Tesla's photos; Classic alternating current electro-magnetic motor; Induction motor operation; Field and armature of equal strengths or magnetic quality; field and armature cores of equal amounts; Coils containing equal amount of copper.
US416195 - Electro-Magnetic Motor - 1889 December 3 - Induction motor operation with two or more windings; Differing phases; Structural and operational conditions; Armature operation conditions and the obedience to the energizing circuit and stator; Construction and organization principles.
US417794 - Armature for Electric Machines - 1889 December 24 - Construction principles of the armature for electrical generators and motors; Simple and economical; Coils or insulated conducting wire (or ribbon) may be wound or formed into bobbins; Position of the bobbins dictate the windings; Armature have polar projections and maximum core-surface exposure to the field magnetic poles; Related to other applicant patents, numbers US327797, US292077, GB9013.
US418248 - Electro-Magnetic Motor - 1889 December 31 - Electric generator; Employment of an artificial cooling device; Inclosing the source of heat and that portion of the magnetic circuit exposed to the heat and artificially cooling the said heated part; Combination of an enclosed source of heat applied to a portion of said core; Magnetized core or body and a conductor within the field of force; Artificial cooling device for reducing the temperature of the heated portion thereof; Means for bringing a cooling gas or fluid in contact with the heated portion of the core, and means for controlling the admission of the same; The combination and coils wound thereon and a connection with a boiler for admitting steam into the channels, as set forth; Magnetized core containing passages or channels; Means for applying heat to a portion of the core.
US424036 - Electro-Magnetic Motor - 1890 March 25 - Cites then common language of his motors referred to as the "magnetic lag" motors; Another form of the induction motor with two or more energizing circuits with differing phase differences are passed to produce rotation or operation of the motor; Magnetism lages electrical parts of energizing effects; Manifest these effect simultaneously and not successively; Related to US405858; Torque is produced to the angular displacement of parts; Best means to achieve these results; prefer the use of alternating currents.
US428057 - Electric Generator - 1890 May 13 - Electric generator; Employment of an artificial cooling device; Inclosing the source of heat and that portion of the magnetic circuit exposed to the heat and artificially cooling the said heated part; Combination of an enclosed source of heat applied to a portion of said core; Magnetized core or body and a conductor within the field of force; Artificial cooling device for reducing the temperature of the heated portion thereof; Means for bringing a cooling gas or fluid in contact with the heated portion of the core, and means for controlling the admission of the same; The combination and coils wound thereon and a connection with a boiler for admitting steam into the channels, as set forth; Magnetized core containing passages or channels; Means for applying heat to a portion of the core.
US433700 - Alternating-Current Electro-Magnetic Motor - 1890 August 5
US433701 - Alternating-Current Motor - 1890 August 5
US433702 - Electrical Transformer Or Induction Device - 1890 August 5
US433703 - Electro-Magnetic Motor - 1890 August 5
US445207 - Electro-Magnetic Motor - 1891 January 27
US447920 - Method of Operating Arc-Lamps - 1891 March 10
US447921 - Alternating Electric Current Generator - 1891 March 10 - A generator that produces alterations of 15000 per second or more.
US454622 - System of Electric Lighting - 1891 June 23
US455067 - Electro-Magnetic Motor - 1891 June 30
US455068 - Electrical Meter - 1891 June 30
US455069 - Electric Incandescent Lamp - 1891 June 30
US459772 - Electro-Magnetic Motor - 1891 September 22
US462418 - Method of and Apparatus for Electrical Conversion and Distribution - 1891 November 3
US464666 - Electro-Magnetic Motor - 1891 December 8
US464667 - Electrical Condenser - 1891 December 8
US487796 - System of Electrical Transmission of Power - 1892 December 13
US511559 - Electrical Transmission of Power - 1893 December 26
US511560 - System of Electrical Power Transmission - 1893 December 26 - Includes a correction.
US511915 - Electrical Transmission of Power - 1894 January 2
US511916 - Electric Generator - 1893 August 19
US512340 - Coil for Electro-Magnets - 1893 July 7 - Effect of mutal relation self-induction exploited; Adjacent coil convolutions formed parts exists so that the potential difference is sufficient to neutralize negative effects; Object to avoid expensive, cumbersome, and difficult condensers; Bifilar coil winding technique.
US514167 - Electrical Conductor - 1894 February 6 - Prevent loss in line conductors; Insulate and encase conductors with a sheathing which is connected to the ground; Sheath or screen; Coaxial cabling.
US514168 - Means for Generating Electric Currents - 1894 February 6 - Generating and utilizing electrical energy discovered by Mr. Tesla; related to US454622 and US462418; Maintenance of intermittent or oscillatory discharges of a condenser of suitable circuit containing translating devices; Discharges take place in insulating liquids (such as oil); Varying spark gap distances; Keep circulating flow in liquid; Illustrates preferred manner.
US514169 - Reciprocating Engine - 1893 August 19 - Provide a means of engines, which under the applied forces such as elastic tension of steam or gas under pressure, that will yield constant oscillatory movements (in wide limits); Functions is constant irrespective of the loads, frictional losses, or other factors (which degrade other engines); Convert pressure into mechanical power; Better at higher temperatures and pressures than previous engines; Same principles of this engine appear later in the modern gasoline motor of automobiles.
US514170 - Incandescent Electric Light - 1894 February 6 - Related to US454622; Incandescent electric lamps; Particular forms of the lamp in which a light giving small body or button of refectatory material is supported by a conductor entering a very highly exhausted globe or receiver; Conducting screen surrounds the supporting conductor.
US514972 - Electric Railway System - 1894 February 20 -
US514973 - Electrical Meter - 1894 February 20
US517900 - Steam Engine - 1893 December 29
US524426 - Electromagnetic Motor - 1894 August 14
US555190 - Alternating Motor - 1896 February 25
US567818 - Electrical Condenser - 1896 September 15
US568176 - Apparatus for Producing Electrical Currents of High Frequency and Potential - 1896 September 22
US568177 - Apparatus for Producing Ozone - 1896 September 22
US568178 - Method of Regulating Apparatus for Producing Electric Currents of High Frequency - 1896 September 22
US568179 - Method of and Apparatus for Producing Currents of High Frequency - 1896 September 22
US568180 - Apparatus for Producing Electrical Currents of High Frequency - 1896 September 22
US577670 - Apparatus for Producing Electric Currents of High Frequency - 1897 February 23
US577671 - Manufacture of Electrical Condensers, Coils and Similar Devices - 1897 February 23 - Improvements of condensers, transformers, self-induction coils, rheostats, and other similar devices; Used in areas where current of high potentials are brought into close proximity; Method of excluding gas or air from the dielectric environment of such devices.
US583953 - Apparatus for Producing Currents of High Frequency - 1897 June 8 - Related to US568176; Conversion of electrical current of ordinary character into high frequency and high potential; Can use either continuous (i.e., direct) or alternating currents.
US593138 - Electrical Transformer - 1897 November 2 - Novel form of transformer or induction-coil and a system for the transmission of electrical energy by means of the same; Improvement of electrical transformers; Develops electrical currents of high potential; Corrects construction principles heretofore manufactured; Higher potential for transmission than ever been practically employed heretofore; Free from the danger of injury from the destruction of insulation; Safe to handle; High-frequency power supply for lighting and other applications.
US609245 - Electrical Circuit Controller - 1898 August 16
US609246 - Electric Circuit Controller - 1898 August 16
US609247 - Electric Circuit Controller - 1898 August 16
US609248 - Electric Circuit Controller - 1898 August 16
US609249 - Electric Circuit Controller - 1898 August 16
US609250 - Electrical Igniter for Gas Engines - 1898 August 16 - Ignition system principles used today in automobiles; Operation of a machine that requires a spark, flame, or any other similar effect; More certian and satisfactory for use of and control by the machinie or apparatus; Charging and dischargin a condensor through switch or commmunicator.
US609251 - Electric Circuit Controller - 1898 August 16
US611719 - Electrical Circuit Controller - 1898 October 4
US613735 - Electric Circuit Controller - 1898 November 8
US613809 - Method of and Apparatus for Controlling Mechanism of Moving Vehicle or Vehicles - 1898 July 1 - New and useful improvements in methods of and apparatus for controlling from a distance; Solution for controlling from a given point the operation of mechanisms; No intermediate wires, cables, or other form of electrical or mechanical connection with the object save the natural media in space; explanation of most practical and effectual method and apparatus; Remote control.
US645576 - System of Transmission of Electrical Energy - 1900 March 20 - Commonly referred to the radio patent; Related to wireless telegraphy; Wireless transmission of electric power through the natural media; Cites well know radiant energy phenomena and the experiments of William Crooke; Corrects previous errors in theory of behavior when used by the methods and means of Mr. Tesla; Discovery of highly important and useful facts which heretofore have been unknown; Deprive dialectic of air when impress electromotive forces of a certain character and magnitude unto it; Conductivity of the air increases with the augmentation of the pressure and the rarefaction; Law of conductivity of the air is quite different than heretofore established; Illustrations of the facts.
US649621 - Apparatus for Transmission of Electrical Energy - 1897 September 2 - Related to US645576; New and useful combinations employed; Transmitting coil or conductor arranged and excited to cause currents or oscillation to propagate through conduction through the natural medium from one point to another remote point therefrom and a receiver coil or conductor of the transmitted signals; Production of currents of excessively high potential; Transmitting station and receiving station.
US655838 - Method of Insulating Electric Conductors - 1900 August 14 - Method and practical application of insulation by freezing and solidification; Expounding on Faraday's hypothesis of freezing substances make them possess a higher dielectric level.
US685012 - Means for Increasing the Intensity of Electrical Oscillations - 1900 March 21 - Producing increase intensity and duration of electric oscillations; Freely-vibrating excitations; Low temperature resonating circuit; Uses of electrical impulse oscillations; Super-conducting oscillator.
US685953 - Apparatus for Utilizing Effects Transmitted from a Distance to a Receiving Device through Natural Media - 1899 June 24 - Heinriech Hertz methods cited; Induction method cited; Ground conduction method cited; Previous methods have limitations that result in great disadvantages for utilization; Wireless transmission developed by Mr. Tesla cited; Transmitting station coil arranged and excited to cause arbitrary or intermitted oscillation propagation to another remote point receiver station coil; Air is excellent insulator; Air strata used for means of conduction for production of generating actions at a distance; Use of metallic conductor; Transmitting apparatus of signals or intelligence should produce effect as strong as possible; Charge a condenser or capacitor to utilize the potential energy.
US685954 - Method of Utilizing Effects Transmitted through Natural Media - 1899 August 1 -
US685955 - Apparatus for Utilizing Effects Transmitted From A Distance To A Receiving Device Through Natural Media - 1899 June 24
US685956 - Apparatus for Utilizing Effects Transmitted through Natural Media - 1899 August 1 -
US685957 - Apparatus for the Utilization of Radiant Energy - 1901 November 5 - 4 illustrations; Radiation charging and discharging conductors; Radiations considered vibrations of ether of small wavelengths and ionize the atmosphere; Radiant energy throws off with great velocity minute particles which are strongly electrified; Rays or radiation falling on insulated-conductor connected to a condenser (i.e., a capacitor), the condenser indefinitely charges electrically; Radiation (or radiant energy) include many different forms; Related to US577671; Transmitted or natural energy can be used; Photoelectric stepping alternating current motors.
US685958 - Method of Utilizing of Radiant Energy - 1901 November 5 - 2 illustrations; Ways of using radiation charging and discharging conductors; Rays or radiation falling on insulated-conductor connected to a condenser (i.e., a capacitor), the condenser indefinitely charges electrically; Radiation (or radiant energy) include many different forms; Related to US577671; Photoelectric stepping alternating current motors.
US723188 - Method of Signaling - 1900 July 16 - Elevated transmitter capacitance; Coil; Earth electrode; Signal generator; Partial basis of radio design.
US725605 - System of Signaling - 1900 July 16 - Elevated transmitter capacitance; Coil; Earth electrode; Signal generator; Apparatus of and method for electrical disturbance or impulses; Transmission of intelligent messages; Govern the movement of distant automata; Radio transmissions; Partial basis of radio design.
US787412 - Art of Transmitting Electrical Energy through the Natural Mediums - 1900 May 16 - Elevated transmitter capacitance; Coil; Earth electrode; Signal generator; Apparatus for generating and receiving electrical signals; Tuned resonant circuits; Physics of propagation; Non-hertzian notes; Globe as conductor; Low frequency oscillations; Basis of radio.
US1061142 - Fluid Propulsion - 1909 October 21 - Transmission and transformation of mechanical power through the agency of fluid; Propelled fluid moves in a natural path; Avoids losses; Easy; Simple.
US1061206 - Turbine - 1909 October 21 - Improvements in rotary engines and turbines; Mechanical power based the vehicle of fluid for power; Known as the Tesla turbine.
US1113716 - Fountain - 1914 October 13 - Improvement in the construction of fountains and aquarian displays; Large mass of fluid in motion; Display of great power; Large displacement of fluid with little expense of energy.
US1119732 - Apparatus for Transmitting Electrical Energy - 1902 January 18 - High-voltage, air-core, self-regenerative resonant transformer; Oscillator for wireless transmission of electromagnetic energy; Tesla coil.
US1209359 - Speed-Indicator - 1916 December 19 - Improvement that uses the adhesion and viscosity of a gaseous medium [preferably air] to measure speed [or measure the torque-transmission] between indicator and driver; Durable; Simple; Inexpensive; Reliable.
US1266175 - Lightning-Protector - 1918 May 14 - Novel and advantageous construction of a protector in accord with the true character of the phenomena; Corrects Benjamin Franklin's hypothesis, and subsequent construction, for lightning protectors.
US1274816 - Speed Indicator - 1918 August 6 - Speedometer that possesses the feature of: Linearly proportional torque readings; Strong low speed torsional effects; not affected by atmospheric density, temperature, nor magnetic influences; Rugged; Simple; Economical.
US1314718 - Ship's Log - 1919 September 2 - Novel and advantageous construction of a ship's log; Instantaneous reading of knots or miles-per-hour.
US1329559 - Valvular Conduit - 1920 February 3 - Improvement by means of a conduit or channel characterized by valvular action; Conduit has baffles, recesses, projections, enlargements, or buckets that channels the flow's movement one way more efficiently; Mechanical diode; One-way valve with no moving parts.
US1365547 - Flow-Meter - 1921 January 11 - Related to the meter of measurement for velocity and quantity of fluid flow.
US1402025 - Frequency-Meter - 1922 January 3 - Ascertain the periodic electric frequency and electric oscillation by the rotation or reciprocation of an electromechanical device.
US1655113 - Method of Aerial Transportation - 1928 January 3 - VTOL aircraft.
US1655114 - Apparatus for Aerial Transportation - 1928 January 3 - VTOL aircraft; Includes a correction.