DE680761 — Arrangement for Converting Direct Current into Alternating Current

DE680761, Anordnung zur Umwandlung von Gleichstrom in Wechselstrom, is a German patent with Hans Coler as inventor and Dr.-Ing. Fritz Modersohn as applicant, filed 1939-09-07. Its full text is reproduced in the source archive dossier of BIOS Final Report No. 1043.

Title:      Anordnung zur Umwandlung von Gleichstrom in Wechselstrom
Inventor:   COLER HANS
Applicant:  FRITZ MODERSOHN DR ING
CPC:        H02M1/20
IPC:        H02M1/20
Date:       1939-09-07

Circuit elements

The drawing is described as Fig. 1 (circuit diagram), Fig. 2 (interrupter with one connection point), Fig. 3 (breaker with four connection points), and Figs. 4–7 (waveforms of the generated alternating current).

Claimed operation

The patent claims generation of AC of any frequency and waveform from DC, with pure DC, chopped DC and pure AC extractable simultaneously by placing consumers at the appropriate points. Frequency equals the number of S2 make-break cycles per unit time; subdividing the resistance ring multiplies frequency. One revolution of the sliding contact K is one period, so revolutions per second equal the AC frequency. In the worked example, W = 20,000 Ω gives a maximum resistance between A and D of 2,000 Ω (the conductor part practically interrupted); with four connection points E1–E4 one revolution yields four periods, so 100 rev/s gives 400 Hz; with six subdivisions and 100 rev/s, 600 Hz. Higher frequencies are claimed through more subdivisions, achieved by increasing the size of the resistance ring. The source also notes that unequal dimensioning of the auxiliary resistors including the bridge resistor allows an alternating current with a superimposed direct current component to be drawn.

Assessment in the source

This is a conventional DC-to-AC conversion patent. It contains no over-unity claim. The dossier does not explain the relationship between this patent and the energy-surplus claims attached to Coler's devices. It should not be read as evidence for the Stromzeuger claims.

The patent text is a design disclosure, not a measurement; see patent-application-as-evidence and reported-vs-measured-performance. Material elsewhere in the same dossier — the "energy difference between the opening and closing impulse" and the "Space Energy Receiver" — belongs to the surrounding Coler text and not to DE680761.