Electrostatic Machines - Patents

Below are some patents that contain material about electrostatic machines. The list is far from complete, of course. These patents are probably available from the several patent sites in the Internet. The copies here are encoded in djvu or pdf format. U. S. patents can be found at the U. S. Patent Office site (in tiff format) or in Google Patents. Other patents can be found at the European Patent Office site (in pdf format). Most of the U. S. patents about electrostatic influence machines can be found there under classes 310/309 and 310/310. Most european patents are under class H02N1.
Patents of H. Wommelsdorf (apparently complete):
DE145440 H. Wommelsdorf. "Kondensatormaschine," 18 July 1902. Condenser machine.
DE161211 H. Wommelsdorf, "Querkonductor für Influenzmaschinen," 23 November 1904. Neutralizer with dial and curve to avoid the driving belt.
DE176415 H. Wommelsdorf, "Aus einzelnen isolierenden Platten mit zwischenliegenden Sektoren bestehende Scheibe für Kondensatormaschinen," 9 August 1905. Disks with embedded sectors.
DE178052 H. Wommelsdorf, "Kondensatormaschine," 8 March 1904. Condenser machine with double rotation.
US882508 H. Wommelsdorf, "Static-Influence Electric Machine," 17 March 1908. Disks with embedded sectors for influence machines.
US883846 H. Wommelsdorf, "Electrical Multiple Influence or Condenser Machine, " April 7 1908. Wommelsdorf condenser machine with double rotation.
DE238344 H. Wommelsdorf, "Scheibe für Influenz- und Kondensatormaschinen," 25 December 1910. Disks with embedded sectors. See also DE271742.
DE244155 H. Wommelsdorf, "Influenzmaschine," 23 August 1910. Machines with insulation in Bakelit.
DE240325 H. Wommelsdorf, "Scheibe für einseitig wirkende Influenzmaschinen," 17 May 1911. Disks with rised borders for increased insulation.
AT56127 H. Wommelsdorf, "Scheibe für Influenz- und Kondensatormaschinen," 11 November 1912. Disks with embedded sectors for condenser machines.
US1071196 H. Wommelsdorf, "Influence Electric Machine," 26 August 1913. Electrostatic machine with insulated sectors and inductors, and disks accessed through the edges. Contains detailed drawings.
DE321622 H. Wommelsdorf, "Kondensatormaschine," 21 March 1919. The classical form of the condenser machine.
DE370980 H. Wommelsdorf, "Elektrophor," 23 February 1922. An electrophorus with two dielectric plates. See also DE376196.
DE392554 H. Wommelsdorf, "Influenzmaschine, deren Beläge nicht nur von einen festen Isoliertoff umgeben sind, sondern auch noch in ein flüssiges Dielektricum tauchen," 13 April 1923. Machine using embedded sectors and liquid dielectric.
DE 420402 H. Wommelsdorf, "Elektrostatische Maschine, deren Induzierende Teile von einen Flüssigen Dielektricum umgeben sind," 25 December 1924. Machine with the inductor plates immersed in liquid dielectric.
DE443699 H. Wommelsdorf, "Influenz- oder Kondensatormaschine," 25 December 1925. Machines with sectors suspended in the air.
DE479991 H. Wommelsdorf, "Stromabnehmer für Influenzmaschinen," 23 February 1928. Charge collecting brush construction.
DE482298 H. Wommelsdorf, "Reibungselektrisierapparat," 29 April 1928. A simple friction machine.
DE546363 H. Wommelsdorf, "Verfahen zum Betrieb von Influenzmaschinen mit mehr als zwei Polen," 7 February 1931. Machines with more than two poles (appears to be the last patent by Wommelsdorf).

Patents of A. Wehrsen:
DE154175 A. Wehrsen and others, "Scheibe für Influenzmaschinen," July 30 1903. Disks with embedded sectors in several levels accessed by pins in the disk face (the disks used in the "Wehrsen" machines). See also DE154176, but I don't know of a machine using those strange disks.
US901666 A. Wehrsen, "Disk for Influence or Static Induction and Condenser Machines," October 20 1908. Corrugated internal sectors for influence machines. Identical to AT36027.
AT36027 A. Wehrsen, "Scheibe für Influenz- bezw. Kondensatormaschinen," 25 January 1909. Corrugated internal disk sectors for influence machines.

Classical or interesting machines:
US1006786 G. S. Piggott, "Space Telegraphy," October 24 1911. A Wimshurst machine in a pressurized box, with a curious drive system and segmented sectors. The machine is used in a radiotelegraphy transmitter.
US275347 P. Atkinson, "Frictional Electrical Machine," April 10 1883. Voss machine.
US331754 P. Atkinson, "Frictional Electrical Generator," December 8 1885. A double Voss machine, with detailed plans.
US700536 G. J. and D. C. Moore, "Apparatus for Demonstrating the Phenomena of Electrical Storms," May 20, 1902. A Voss machine in a box with "house and cloud" attachments for lightning rod demonstrations.
US827497 O. Baysdorfer, "Static Electric Machine," July 31 1906. Double Voss machine in a box with some different structural details
US873178 W. C. Shinn, "Static Electric Machine," December 10, 1907. Double Voss machine in a box with attachments for lightning demonstrations.
US1043030 T. H. Patee, "Static Electric Machine," October 29, 1912. Double Voss machine in a box with attachments for lightning demonstrations, and some different structural details.
US634467 K. S. Lemström, "Electrical Influence-Machine," 10 October 1899. A cylindric Wimshurst machine.
US720711 K. S. Lemström, "Electrical Influence-Machine," 17 February 1903. A better structure for a cylindric Wimshurst machine.
US809761  E. Thomson, "Electrostatic Influence Machine," 9 January 1906. A Wimshurst machine using metal plates, without support disks.
US692737 H. B. Todd, "Static Electric Machine," 4 February 1902. A Wimshurst machine with extra plain disks between the normal disks, rotating along with them.
US410053 R. Voss, "Influence Machine," 27 August 1889. The Voss machine.
US776997 J. H. G. Burboa, "Static Electric Machine," 6 December 1904. Voss machine using a belt instead of a disk.
GB189815100 W. R. Pidgeon, "Electrical Influence Machines," 18 March 1899. Pidgeon machine with extra inductors and cylindric version.
GB189922517 W. R. Pidgeon, "Electrical Influence Machines," 21 July 1900. The Pidgeon triplex machine.
GB190701162 A. E. Dean, "Improvements in Electrical Influence Machines commonly called Static Machines," 11 July 1907. Improved multiple Bonetti machine, with chain drive and easily removable disks.
GB190022572 Karl Schall, "Improvements in or relating to Electrostatic Machines", 23 May 1901, A modification of the Voss machine, with inductor plates suspended behind slowly rotating fixed disks, to prevent polarity reversals.

Modern machines:
US1991236 R. J. Van de Graaff, "Electrostatic Generator", 12 February 1935. The Van de Graaff generator.
US2567373 L. J. Giacoletto and I. Wolff, "Electrostatic generator," 11 September 1951. Probably the first regenerative machine using diodes as switches. Equivalent to Belli's machine with back-and-forth movement.
US3175104 C. D. Curtis, "High voltage electric generator," 23 March 1965. Regenerative generator using just one variable capacitor. Equivalent to Bennet's doubler with one capacitor fixed and a different grounded node. Has an interesting analysis of how it works.

Nonregenerative machines:
US645675 E. Thomson, "High potential apparatus," 20 March 1900. Machine using capacitors charged in parallel and discharged in series, using AC power with synchronized switches.
US3094653 C. F. Drexel and D. B. Le May, "Electrostatic generator," 18 June 1963. Generator using a biased variable capacitor and a rectifier with diodes.


Developed and Maintained by Antonio Carlos M. de Queiroz.
Created: 01 November 2000.
Last update: 17 March 2017.

Lamento informar que o Prof. Antonio Carlos Moreirão de Queiroz faleceu há algum tempo.
Sei que esta página é visitada constantemente. Assim, gostaria de saber se temos algum visitante (interessado) que seja da UFRJ. Se for, por favor, envie um e-mail para watanabe@coe.ufrj.br.
Comento que é impressionante ver o que Moreirão foi capaz de fazer. Ele não só projetou os circuitos, mas também fez todo o trabalho de marceneiro (melhor que muitos que já vi e eram profissionais).
Segundo Moreirão contou em uma palestra, ele só levou choque uma vez. Sem querer encostou o dedo médio em um capacitor com alta tensão que se descarregou através do dedo. A corrente ao passar por uma das articulações a danificou e doía sempre que dobrava esse dedo. Mas, segundo ele, já tinha acostumado.

E. Watanabe (ELEPOT)