List of Tesla patents

Below is a list of Tesla patents. Nikola Tesla was an inventor who, it is said, accumulated 700-plus patents worldwide for his inventions. Some of Tesla's patents are not accounted for, and various sources have discovered some that have lain hidden in patent archives. There are a minimum of 272 patents issued to Tesla in 25 countries that have been accounted for. Many of Tesla's patents were in the United States, Britain, and Canada, but many other patents were approved in countries around the globe. Many inventions developed by Tesla were not put into patent protection(Cheney, 62).

Contents

1 Introduction 2 American 2.1 First fifty patents 2.2 Fifty-one to one hundred 2.3 One hundred and one plus 2.4 Reissued patent 2.5 Anomalies 3 British 4 Canadian 5 Other countries 6 See also 7 Related links and references 7.1 Patent resources 8 Futher readings

Introduction

Tesla's inventions and developments include the induction motor, the bifilar coil, 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 oscillators, devices for voltage magnification by standing waves, logic gates for secure radio frequency communications, devices for x-rays, devices for ionized gases, devices for high field emission, devices for charged particle beams, methods for providing extremely low level of resistance to the passage of electrical current, means for increasing the intensity of electrical oscillations, 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), US4869598 (Temperature-sensitive multiple-layer thin film superconducting device), 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

First fifty patents

1. Template:US patent - Commutator for Dynamo Electric Machines - 1886 January 26 - Elements to prevent sparking on dynamo-electric machines; Drum-style with brushes.
2. Template:US patent - Regulator for Dynamo Electric Machines - 1886 October 19 - Automatic regulation of energy levels; Mechanical device to shift brushes.
3. Template:US patent - 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.
4. Template:US patent - Electric arc lamp - 1886 February 9 - Arc lamp's automatic fail switch when arc possesses abnormal behavior; Automatic reactivation.
5. Template:US patent - Regulator for dynamo electric machines - 1886 March 2 - Two main brushes connected to helices coil ends; Intermediate point branch shunt connection for third brush.
6. Template:US patent - 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.
7. Template:US patent - Dynamo electric machine - 1887 March 22 - Improve construction; Facilitate easier construction; Reduce the cost; Magnetic frame; Armature; Alternating current synchronous motor.
8. Template:US patent - 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.
9. Template:US patent - Electro Magnetic Motor - 1888 May 1 - Novel form and operating mode; Coils forming independent energizing circuits; Connected to an alternating current generator; Synchronous motor.
10. Template:US patent - 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.
11. Template:US patent - Electro Magnetic Motor - 1888 May 1 - Rotation is produced and maintained by direct attraction; Utilizes shifting poles; Induction magnetic motor.
12. Template:US patent - 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.
13. Template:US patent - 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.
14. Template:US patent - 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.
15. Template:US patent - 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.
16. Template:US patent - 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.
17. Template:US patent - 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.
18. Template:US patent - 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.
    Missing image
    US390721.png

    Tesla's US390721 Patent for a "Dynamo Electric Machine"
19. Template:US patent - 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.
20. Template:US patent - 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.
21. Template:US patent - Thermo Magnetic Motor - 1888 January 15 - Widely known that heat applied to a magnetic body will lessen its 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.
22. Template:US patent - 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.
23. Template:US patent - Electro Magnetic Motor - 1889 June 25 - Torque, instead of being the result in the difference in the magnetic periods or phases of the poles 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 simultaneously, 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.
24. Template:US patent - 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.
25. Template:US patent - 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 its 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.
26. Template:US patent - 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.
27. Template:US patent - 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).
28. Template:US patent - 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.
29. Template:US patent - 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.
30. Template:US patent - 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.
31. Template:US patent - 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.
32. Template:US patent - 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.
33. Template:US patent - 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.
34. Template:US patent - 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.
35. Template:US patent - Pyromagneto 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.
36. Template:US patent - Alternating-Current Electro-Magnetic Motor - 1890 August 5 - Rotation of a electromagnetic motor is produced by the magnetic movements or the maximum of the pole's (or piont's) magnetic effects from the cojoined actions (or the two energizing circuits) through which alternating currents (or similar rapidly-varying currents) are passed through; Multiple magnets are powered by artificial currents; Inverse strength of magnetism on stator for best rotation; Creates multiple phase through one circuit from one power source.
37. Template:US patent - Alternating-Current Motor - 1890 August 5 - Two sets of field-pole pieces of energized independently by the same source; Closed magentic iron shunts or bridges in sets or series.
38. Template:US patent - Electrical Transformer Or Induction Device - 1890 August 5 - Main magnetic core and the primary and secondary coils interposed by a magnetic shield or screen in between the coils or around one of the coils; Coils can be wound upon or built up around the magnetic shield; Adapted to or capable of being magnetically saturated by a predetermined current strength below the maximum in the primary.
39. Template:US patent - Electro-Magnetic Motor - 1890 August 5 - Describes the combination, in a alternating current motor, of a energizing coil and a core composed of two parts (one being protected from magnetization from the other one interposed between it and the coil); A rotating armature is motivated by the induced fields; Alternatively, a field magnet composed of a coil and core (with two section in proximity of the coil and a inner section between the same); Also, a field magnet each composed of a coil and core (with two section in proximity of the coil and a inner section between the same).
40. Template:US patent - Electro-Magnetic Motor - 1891 January 27 - Describes the combination, in a motor, of a primary energizing circuit (connected to a generator) and a secondary circuit in inductive relation to the primary; Each circuit has a different electrical character, resistance, induction capability, or number and type of windings.
41. Template:US patent - Method of Operating Arc-Lamps - 1891 March 10 - Abate or render inaudible sound emitted by arc lamps that are powered by (or supplied with) alternating currents by increasing the alerations (or pulsations) above the auditory level.
42. Template:US patent - Alternating Electric Current Generator - 1891 March 10 - A generator that produces alterations of 15000 per second or more.
43. Template:US patent - System of Electric Lighting - 1891 June 23 - Apparatus devised for the purpose of converting and supplying electrical energy in a form suited for the production of certain novel electrical phenomena which require currents of higher frequency and potential.
44. Template:US patent - Electro-Magnetic Motor - 1891 June 30 - Alternating current motor, with field magnets and energizing circuit armature-circuit and a core adapted to be energized by currents induced in its circuit by the currents in the field circuit; Condenser connected with or bridging the armature-circuit (e.g., the rotating element of the motor); Energizing circuit formed by coils wound thereon in a different inductive relations to the field and joined in a continuous or closed series; Combination of a condenser the plates of which are connected, respectively, to the junctions of the circuits or coils.
45. Template:US patent - Electrical Meter - 1891 June 30 - Method of computing the amount of electrical energy expended in a given time in an electrical circuit; Operates by maintaining by the current a potential difference between two conductors in an electrolytic solution (or cell) uniform throughout the whole extent of such conductors exposed to the solution; Measurement of the variation of the resistance in one or both conductors dues to the gain or loss of metal by electro-deposition; Electrolytic cell and conductors passing through the cell and connected in series with a translating device; One or more resistances connected with the conductors and cell for establishing a potential differnce between the two conductors through the solution of the cell; Tubular cell contains electrolytic solution and closed at each end.
46. Template:US patent - Electric Incandescent Lamp - 1891 June 30 - Incandescent lamp consisting of two isolated refractory conductors contained in a non-striking vacuum and adapted to produce light by incandescence; Globe or receiver exhausted to the non-striking point with two mounted isolated bodies (or metal wires) of refractory conducting material to emit light and sealed in; Terminal to connect with a electrical energy source; Refractory conducting material not to be rendered incandescent coated or covered with insulation.
47. Template:US patent - Electro-Magnetic Motor - 1891 September 22 - Alternating current non-synchronizing electric motor coupled with a synchronizing alternating current motor whereby the former starts the latter and throws it into synchronism with its actuating current; Switch mechanism for directing the current through either or both of the motors; Combonation of two motors (one a alternating current torque motor [e.g., shifting poles via the energizing circuit] and the other a synchronizing alternating current motor) the armatures of which are mounted upon the same shaft; Switching circuit directing the alternating current or currents through the several circuits of one motor or the single circuit of the other.
48. Template:US patent - Method of and Apparatus for Electrical Conversion and Distribution - 1891 November 3 - Apparatus devised for the purpose of converting and supplying electrical energy in a form suited for the production of certain novel electrical phenomena which require currents of higher frequency and potential.
49. Template:US patent - Electro-Magnetic Motor - 1891 December 8 - Alternating current motor provided with two or more energizing or field circuits; One circuit connected to current source and the other (or others) in inductive relation thereto; One circuit connected to alternating currents and the other constituting high potential secondary circuit; Condenser interposed in the inductive circuit.
50. Template:US patent - Electrical Condenser - 1891 December 8 - Electrical condenser composed of plates or armatures immersed in oil; Plates or armatures can be adjustable.

Fifty-one to one hundred

1. Template:US patent - System of Electrical Transmission of Power - 1892 December 13 - Alternating current gennerator comprising independent armature-circuits formed by conductors alternately disposed; Currents developed differ in phase and the field magnet poles in excess of the number of armature-circuits; Motor having independent energizing circuitsconnected to the armature-circuit of the alternating current generator; Rotating magneto-electric machine yielding a given number of current impulse or alterations for each turn or revolution; Poles which in number are less than the number of current impulses produced in each motor-circuit by one turn or revolution; Multipolar alternating-current machine.
2. Template:US patent - Electrical Transmission of Power - 1893 December 26 - Method of poperating motors having indepedent energizing circuits; Passing alternating currents through circuits and retarding the phases of the current in one circuit to a greater extent; Directing alternating currentsfrom a single source through both circuits of a motor and varying or modifying the relative resistance or self-induction of motor circuits, producing in currents differences in phases.
3. Template:US patent - System of Electrical Power Transmission - 1893 December 26 - Motor having independent energizing circuits connected with a source of alternating currents; Means of renering the magnetic effects to said energizing circuit of difference pahse; Armature within the influence of the energizing circuit; Engergizing circuits connected in derivation or multiple arc and of different active or variable resistance (or self-inductance); Pairs of mains conncted and a multiple circuit differential phase; Change of time-period of currents passing through a electro-motive phase-changing device interpose between the mains and the destination; Includes a correction.
4. Template:US patent - Electrical Transmission of Power - 1894 January 2 - Method of operating electro-magnetic motors; Passing alternating curents through on of the energizing circuits and inducing by such current in the other energizing circuit or circuits of the motor.
5. Template:US patent - Electric Generator - 1893 August 19 - Combination with the piston or equilivant element of an engine which is free to reciprocate under the action thereon of steam or a gas under pressure, of the moving conductor or element of an electric generator in direct mechanical connection; Engine and generator being adjusted by their relative adjustment with respect to period to produce currents of constant period; Electric generator having inducing or induced elements one of which is capable of oscillation in the field of force, the moveable element being carried by the piston rod of the enegine; Relation as to respect of period of electrical vibration will not distrub the period of the enegine; Cylinder and piston reciprocating by steam or gas under pressure of a spring maintained in vibration by the movment of the piston, and the electric generator, the moveable conductor or element of which is connected with the piston; Method of constructing and adapting elements; Imparting the oscillation of an engine to the moving element of an electric generator and regulating the period of mechanical oscillation by adjestment of the reaction of the electric generator.
6. Template:US patent - Coil for Electro-Magnets - 1893 July 7 - Effect of mutual 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.
7. Template:US patent - 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.
8. Template:US patent - 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.
9. Template:US patent - 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.
10. Template:US patent - 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; Single node vacua tube.
11. Template:US patent - Electric Railway System - 1894 February 20 - Utilizes high potentials and high frequencies; Insulated and screened supply conductor along the line of travel; Induction bar or plate in inductive relation to the screened conductor and a electrical connection to the motor.
12. Template:US patent - Electrical Meter - 1894 February 20 - Method of measuring the amount of electrical energy expended in a given time in a electric circuit of alternating currents; High tension discharge through a rarefied gas between two conductors; Computing from the amount of the particles thrown off from a conductors or one of the same by action of the discharge of the energy expended; Primary coil in series with a translating device; High tension secondary; Two carbon conductors sealed in a exhausted receiver and coated with an insulating material on three sides, one terminal of each conductor being connected to a terminal of a secondary.
13. Template:US patent - Steam Engine - 1893 December 29 - Cylinder and reciprocating piston (with a spring) and controlling slide valve of an engine adapted to be operated by steam or a gas system under pressure of an independently controlled engine of constant period operating the said valve.
14. Template:US patent - Electromagnetic Motor - 1894 August 14 - Alternating curtrent motor with energizing coils adapted to be connected with an external circuit of cores of different magnetic susceptibility so as to exhibit differences of magnetic phase under the influence of an energising current; Rotary aramture of magnetic poles and coils adapted to be connected with the external circuit surrounding the same; Cores constructed of different size, length, mass, or material whereby their magnetic phase will differ in time.
15. Template:US patent - Alternating Motor - 1896 February 25 - Related to US381968 and US382280; Mode and plan of operating electric dynamic motor generators by progressive shifting; Magneto-electric machine; Dynamo motor conversion with two independent alternating current circuits; Transmission of energy; Rotating magnetic field principles.
16. Template:US patent - Electrical Condenser - 1896 September 15 - Condenser constructed or provided with means for exclusion of air or gas; Armature composed of a conducting liquid; Armatures in two separate bodies of conducting liquid insulated electrically and contained in a receptacle; Insulating liquid seal on the surface of the conductive liquids.
17. Template:US patent - Apparatus for Producing Electrical Currents of High Frequency and Potential - 1896 September 22 - Conversion of direct current into currents of high frequency. Combination of high self-inductance circuit, choking coil circuit controllers adapted to make and break the circuit, a condenser into which the back-emf discharges when interrupted, and a transformer through the primary of which the condenser discharges; Motor for driving the controller; 'Current of high electromotive force (voltage) which is induced at each break of the main circuit (back-emf) furnishes the proper current for charging the condenser (capacitor).'
18. Template:US patent - Apparatus for Producing Ozone - 1896 September 22 - Primarily provides a simple, cheap, and effective apparatus for the production of ozone (or such gases); Obtained by the action of high-tension electrical discharges; Related to US462418 (November 3, 1891) and US454622 (June 23, 1891); In combination with a low self-induction and resistance circuit of direct currents, of a controller for making and breaking the same, a series-wound motor included in or connected with the charging-circuit and driving the controller; A condenser around the point of interruption in a circuit around the controller, and a transformer through the primary of which the condenser discharges (producing the potential necessary for such primary discharge and the coil raises the potential of such discharge) and which is in the discharge-circuit of the condenser; Device for maintaining a current of air between the discharge-surface; A fan-motor (maintaining a current of air between the discharge-surfaces) is connected with the charging-circuit.
19. Template:US patent - Method of Regulating Apparatus for Producing Electric Currents of High Frequency - 1896 September 22
20. Template:US patent - Method of and Apparatus for Producing Currents of High Frequency - 1896 September 22
21. Template:US patent - Apparatus for Producing Electrical Currents of High Frequency - 1896 September 22
22. Template:US patent - Apparatus for Producing Electric Currents of High Frequency - 1897 February 23. Two input circuits are each pulsed with a 25 % duty. Additionally, the brushes are phased so that on states (discharges) never overlap. The output circuit has a toggled 50% output duty, double the duration of the input pulse. Resultant back-emf is rectified to capacitors, and fed through a Tesla coil to a load.
23. Template:US patent - 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; Insulated material rendered fluid by heat; Material permeated the interstices of device and held under pressure; Material cooled and solidified under pressure.
24. Template:US patent - 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.
25. Template:US patent - 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.
26. Template:US patent - Electrical Circuit Controller - 1898 August 16 - A circuit controller (see also 609245, 609246, 609247, 609250, 609251, 611719).
27. Template:US patent - Electric Circuit Controller - 1898 August 16 - A circuit controller (see also 609245, 609246, 609247, 609250, 609251, 611719).
28. Template:US patent - Electric Circuit Controller - 1898 August 16 - A "circuit controller in which an independently-mounted terminal operated in a similar manner by a rotating body of conducting fluid may be enclosed within a gas-tight receptacle".
29. Template:US patent - Electric Circuit Controller - 1898 August 16 - A circuit controller (see also 609245, 609246, 609247, 609250, 609251, 611719) in which one terminal body moves through jets or stream intermittently and intercepts jets or streams.
30. Template:US patent - Electric Circuit Controller - 1898 August 16 - A circuit controller (see also 609245, 609246, 609247, 609250, 609251, 611719).
31. Template:US patent - 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 certain and satisfactory for use of and control by the machine or apparatus; Charging and discharging a condensor through switch or communicator.
32. Template:US patent - Electric Circuit Controller - 1898 August 16 - A circuit controller (see also 609245, 609246, 609247, 609250, 609251, 611719).
33. Template:US patent - Electrical Circuit Controller - 1898 October 4 - A circuit controller (see also 609245, 609246, 609247, 609250, 609251, 611719).
34. Template:US patent - Electric Circuit Controller - 1898 November 8 - A circuit controller (see also 609245, 609246, 609247, 609250, 609251, 611719).
35. Template:US patent - Method of and Apparatus for Controlling Mechanism of Moving Vehicle or Vehicles - 1898 July 1 - Tesla "Boat" patent; First logic gate; Art of controlling the movements and operation of a vessel or vehicle at a distance; Electromagnetic waves conveyed to vessel by the natural media and rendering by their means the controlling-circuit active or inactive; 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.
36. Template:US patent - System of Transmission of Electrical Energy - 1900 March 20 - Commonly referred to as 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.
37. Template:US patent - 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.
38. Template:US patent - Method of Insulating Electric Conductors - 1900 October 23 - 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 to insulate transmission conductors; Improvements in the method set out by Faraday; Method of insulating electrical conductors which consist in surrounding or supporting said conductors by a material which acquires insulating properties when frozen or solidified; Method of maintaining a conductor within gaseous cooling agent by the continuous application of said agent; Trough or conduit with circulating cooling agents; Reissued as Template:US patent.
39. Template:US patent - Means for Increasing the Intensity of Electrical Oscillations - 1900 March 21 - A method for producing a "great increase in the intensity and duration of the (electrical) oscillations excited in a freely-vibrating or resonating circuit by maintaining the same at a low temperature".
40. Template:US patent - 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.
41. Template:US patent - Method of Utilizing Effects Transmitted through Natural Media - 1899 August 1 -Ultilizing effects or disturbances transmitted through the natural media, which consists on charging a storage device with energy from an independent source, controlling the charging of said device by the actions of the effects or distrubances (during succceeding intravals of time determined by means of such effects and distrubances corresponding in succession and duration of the effects and distrubances), and coincidently using the stored energy for the operating a receiving device; Independent source may be at a distant transmitting electrical energy; Receiving device circuit discharges the acculmulated stored energy (which may be potential energy) and causing variations in resistance in a circuit including an independent source of electricity and a storage device; Effecting the storage (such as, in a condenser) during any desired time interval and under control of such effcts of distrubances; Accumiulated energy may operate a transformer (by discharging through a primary circuit at predetermined times) which, from the secondary currents, operate the receiving device.
42. Template:US patent - Apparatus for Utilizing Effects Transmitted From A Distance To A Receiving Device Through Natural Media - 1899 June 24
43. Template:US patent - Apparatus for Utilizing Effects Transmitted through Natural Media - 1899 August 1 -
    

    

    US685957 : Utilization of Radiant Energy
44. Template:US patent - 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.
45. Template:US patent - 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.
46. Template:US patent - Method of Signalling - 1900 July 16 - Elevated transmitter capacitance; Coil; Earth electrode; Signal generator; Partial basis of radio design.
47. Template:US patent - System of Signalling - 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.
48. Template:US patent - 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.
49. Template:US patent - 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.
50. Template:US patent - Turbine - 1909 October 21 - Improvements in rotary engines and turbines; Mechanical power based the vehicle of fluid for power; Known as the Tesla turbine; Bladeless turbine design; Utilizes boundary layer effect; Fluid does not impact the blades as in a conventional turbine.

One hundred and one plus

1. Template:US patent - Fountain - 1914 October 13 - Improvement in the construction of fountains and aquarium displays; Large mass of fluid in motion; Display of great power; Large displacement of fluid with little expense of energy.
2. Template:US patent - 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.
   

   

   View in elevation
   Free terminal and circuit of large surface with supporting structure and generating apparatus
3. Template:US patent - 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.
4. Template:US patent - 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.
5. Template:US patent - 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.
6. Template:US patent - Ship's Log - 1919 September 2 - Novel and advantageous construction of a ship's log; Instantaneous reading of knots or miles-per-hour.
7. Template:US patent - 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.
8. Template:US patent - Flow-Meter - 1921 January 11 - Related to the meter of measurement for velocity and quantity of fluid flow.
9. Template:US patent - Frequency-Meter - 1922 January 3 - Ascertain the periodic electric frequency and electric oscillation by the rotation or reciprocation of an electromechanical device.
10. Template:US patent - Method of Aerial Transportation - 1928 January 3 - VTOL aircraft; Describes a method of achieved vertical take-off, transition to and from horizontal flight, and vertical landing, with a tilting rotor.
11. Template:US patent - Apparatus for Aerial Transportation - 1928 January 3 - VTOL aircraft; Includes a correction.

Reissued patent

1. Template:US patent - Method of Insulating Electric Conductors - 1900 October 23 - Expounding on Faraday's hypothesis of freezing substances make them possess a higher dielectric level to insulate transmission conductors; Improvements in the method set out by Faraday; Method of insulating electrical conductors which consist in surrounding or supporting said conductors by a material which acquires insulating properties when frozen or solidified; Method of maintaining a conductor within gaseous cooling agent by the continuous application of said agent; Trough or conduit with circulating cooling agents.

Anomalies

In the book "Man out of Time", there are references to missing patents (Cheney, pg. 236). Some patents of his experiments are lost to history, as well as some of the scientific notes and records pertaining to Tesla's patents. These, though, are alluded to in the redacted FBI files. These may be among effects seized by government agents and military intelligence officers following the Tesla's death in 1943. In various patent logs, it is recorded Tesla received Template:US patent for "Filings Tube" (such as Charles Henry Isewall's "Wireless Telegraphy" (New York, 1904)_{[1] (http://www.yurope.com/org/tesla/patente.htm)}). This number does not match the U. S. Patent office records (that patent is issued to G. Kelly for an "Illuminating torch").

British

• patent number - name of patent - date - notes on patent

1. GB1877 - Improvements in Electric Lamps
2. GB2801 - Improvements in Reciprocating Engines and Means for Regulating the Period of the same
3. GB2812 - Improvements in Methods of and Apparatus for the Generation of Electric Currents of Defined Period
4. GB2975 - Improvements in Dynamo Electric Machines
5. GB6481 - Improvements relating to the Electrical Transmission of Power and to Apparatus therefor
6. GB6502 - Improvements relating to the Generation and Distribution of Electric Currents and to Apparatus therefor
7. GB6527 - Improvements relating to Electro-motors
8. GB8200 - Improvements relating to the Transmission of Electrical Energy - 1905 April 17
9. GB8575 - Improved Methods of and Apparatus for Generating and Utilizing Electric Energy for Lighting Purposes
10. GB11293 - Improvements relating to the Utilization of Electromagnetic, Light, or other like Radiations Effects or Disturbances transmitted through the Natural Media and to Apparatus therefor
11. GB11473 - Improvements in Alternating Current Electro-magnetic Motors
12. GB13563 - Improvements in, and relating to, the Transmission of Electrical Energy
13. GB14550 - Improvements relating to the Insulation of Electric Conductors
14. GB14579 - Improvements in and relating to the Transmission of Electrical Energy - 1901 July 17
15. GB16709 - Improvements relating to the Conversion of Alternating into Direct Electric Currents
16. GB19420 - Improvements in Alternating Current Electro-magnetic Motors
17. GB19426 - Improvements in the Construction and Mode of Operating Alternating Current Motors
18. GB20981 - Improvements to the production, regulation and utilization of electric currents of high frequency, and apparatus therefor - 1896 August 22
19. GB24001 - Improved method of imparting energy to or deriving energy from a fluid and apparatus for use therein - 1910 October 17 - Bladeless turbine having disc rotors; Openings in the central portions and separating star-washers; Riveted into single, solid structure; Keyed to the shaft; Turbine or rotary engine.
20. GB24421 - Improvements in systems for the transmission of electrical energy and apparatus for use therein - 1897 October 21
21. GB26371 - Improvements in the method of and apparatus for controlling the mechanism of floating vessels or moving vehicles - 1898 December 13
22. GB174544 - Improvements in methods of and apparatus for the generation of power by elastic fluid turbines - 1921 April 1
23. GB179043 - Improved process and apparatus for production of high vacua - 1921 March 24
24. GB185446 - Method of and apparatus for aerial transportation - 1921 April 04
25. GB186082 - Improvements in the Construction of Steam and Gas Turbines - 1922 September 25 - Two heavier end-plate; Tapered toward the periphery; Reduces maximum centrifugal stress; Turbine.
26. GB186083 - Economic Transformation of the Energy of Steam by Turbines - 1922 September 25 - Improvements to increase efficiency of steam power plants and thermo-dynamic transformers; Producing motive power; Economical; Operable at very high temperature; Operable with cheap fuel; Avoids deteriorating actions previously common; System is related to the Tesla turbine.
27. GB186084 - Improved process of and apparatus for deriving motive power from steam - 1921 March 24
28. GB186799 - Process for and apparatus for balancing rotating machine parts - 1921 September 02

Canadian

• patent number - name of patent - date - notes on patent

1. CA24033 - Improvements in Dynamo Electric Machines - 1886 April 24
2. CA29537 - Improvements in Methods of and Apparatus for the Electrical Transmission of Power - 1888 May 1
3. CA30172 - Improvements in Methods of and Apparatus for Converting and Distributing Electric Currents - 1888 May 1
4. CA33317 - Improvements in Methods and Apparatus for Converting Alternating into Direct Currents - 1889 December 19
5. CA135174 - Improvements in Fluid Propulsion - 1910 November 24 - Tesla Pump
6. CA142352 - Improvement in the Art of Transmitting Electrical Energy Through the Natural Mediums - 1912

Other countries

The following is a list of other countries that hold known patents by Tesla. The number following the country is the number of known patent in their records. This is not an exhaustive list. The total number may be incomplete and additional countries still may hold patents unknown.

Country		Number
Argentina		1
Australia		3
Austria		4
Belgium		21
Brazil		2
Cuba		1
Denmark		3
German		19
France		26
India		1
Italy		11
Japan		1
Hungary		7
Mexico		1
New South Wales		2
New Zealand		1
Norway		3
Rhodesia		1
Russia		4
Spain		4
Switzerland		4
Sweden		4
Transvaal		1

See also

• Tesla turbine
• Tesla coil
• List of Edison patents

Related links and references

General

• "Differing figures have been cited for the total number of patents obtained by Tesla worldwide. What is the actual number? (http://www.tfcbooks.com/teslafaq/q&a_047.htm)", Twenty First Century Books, Breckenridge, CO.

Patent lists

• Hand scanned patents (http://www.infostream.net/fred/patents) - Mirror (http://www.keelynet.com/tesla/)
• Mall-USA patents list (http://www.mall-usa.com/BPCS/grant_tesla.html)
• Helping Hand Consulting patents list (http://www.helpinghandconsulting.com/tesla/ftpteslapatents.html)
• The very last page of the internet's patents list (http://www.theverylastpageoftheinternet.com/menu/tesla_patents.htm)
• Twenty First Century Books Patents (http://www.tfcbooks.com/patents/patents.htm)
• Svenson's U.S Tesla Patents (http://www.svensons.com/Tesla/)
• Pepe's Tesla Pages (http://www.tesla.hu/) - Nikola's Page (http://www.tesla.hu/tesla/tesla.htm) (Hungarian - original images of text)

Books

• My Inventions: The Autobiography of Nikola Tesla (http://www.lucidcafe.com/library/96jul/teslaautobio.html)

Patent resources

• US Patent and Trademark Office (http://www.uspto.gov)
• World Intellectual Property Organization (http://www.wipo.org/)
• Delphion IP Research (http://www.delphion.com/)
• Canadian Patents Database (http://patents1.ic.gc.ca/)
• Japan Patent Office (http://www.jpo.go.jp/)
• European Network of Patent Databases (http://gb.espacenet.com/)

Futher readings

• "Mr. Tesla's Circuit Interrupters". The Electrical World, August 20, 1898.
• Martin, Thomas Commerford. "The Inventions, Researches and Writings of Nikola Tesla - 1894", Kessinger Publishing Company, March, 1997. ISBN 1564597113
• Johnston, Ben [Ed.]. "My Inventions: The Autobiography of Nikola Tesla", Hart Brothers Publishing, October, 1982. ISBN 0910077002
• Cheney, Margaret, Tesla: man out of time, ISBN 0743215362