US 2466299 A
Description (OCR text may contain errors)
April 5,1949. L. BLQK 2,466,299
CIRCUIT FOR BALANCING POTENTIAL FLUCTUATIONS Filed March 25, 1943 vzInr G i 3 4 6-o 1 4 5 a 1 T E iNVENTOR LOURENS BLOK ATTORNEY Patented Apr. 5, 1949 CIRCUIT FOR BALANCING POTENTIAL FLUCTUATIONS Lourens Blok, Eindhoven, Netherlands, assignor to Hartford National Bank and Trust Company, Hartford, Conn, as trustee Application March 23, 1943, Serial No. 480,185
In the Netherlands September 17, 1940 Section 1, Public Law 690, August 8. 19%
Patent expires September 17, 1960 3 Claims.
.similar fluctuations and this is in some cases inadmissible, for example in the-case or" a lowfrequency oscillator to be used for measuring or adjusting purposes.
For stabilizing supply voltages it is known to use glow discharge lamps which are operated in the substantially flat part of the current-voltage characteristic curve. Thus, however, complete compensation is not obtained. and moreover it is necessary for a sufiiciently large regulating range to choose the current that passes through the lamp so as to be at least as high as the supply current, the efficiency being thereby interfered with.
The present invention meets the said two dii ficulties.
According to the invention, one of the terminals of the source of direct voltage between pensation or over-compensation of the potential fluctuations which is desired for any case is reached.
v If therefore the output of a direct voltage as constant as possible is, for example, required a 100% compensation will have to be provided for.
If, however, the point in question is the directcurrent supply of an aggregate comprising a plurality of discharge tubes it is preferable to over-compensate and to supply only part of the said tubes, if possible only one, with the (over)- compensated voltage and all the other tubes with the non-compensated voltage. In the case of sufficient over-compensation the same effect is thus nevertheless achieved as though all of the tubes were supplied with a perfectly constant voltage, and there is by now the additional advantage that the current and hence the loss of energy in the regulating impedance may remain small.
In this manner it is possible, for example with a low frequency oscillator, to provide for an out put which is independent of potential fluctua tions of the electric lighting mains, in that only one of the two oscillators, whose difference irequency constitutes the desired low frequency, is supplied with the overcompensated direct voltage, but the other oscillator and the amplifier with the non-compensated voltage.
In order that the invention may be clearly understood and readily carried into efiect this embodiment of the invention will now be de scribed-more fully with reference to the accord panying drawing, in which one example is grammatically shown.
Between the terminals l and 2 of a source direct voltage, for example an anode tension supply unit, there is a voltage E which may vary in consequence of supply voltage fluctuations and/or temperature fluctuations.
A low frequency oscillator T is supplied from. the terminals E and 2 with the interposition of a resistance R2 and is provided for this purpose with connecting terminals and i. The oscillator part G is, however, precluded from this supply and separate connecting terminals 5 and ii are provided for its supply.
In view of the latter terminals, the terminal (i is connected to the right hand end of the resist ance R2, whereas the terminal 5 is connected to the point of connections between a resistance R1 and a glow discharge lamp L which are connected in series between the terminals l and 2.
In these circumstances potential fluctuations between i and 2 will become manifest in com paratively unweakened condition between 3 and 4 so that if the output T has to remain unaltered the voltage between 5 and 6 will have to manifest similar but oppositely directed potential fluctuations. This result may be obtained by means of the illustrated circuit arrangement by a suitable amazes choice of the resistances R1 and Re, as will be set out in greater detail.
The resistance R1 is naturally to be chosen so that at the mean value of E the lamp L operates about centrally in its regulating range so that the value of the said resistance is thus fixed.
If designating the instantaneous voltage across the glow discharge lamp by V0, that between the terminals 5 and 6 by V and the current in the resistance R: by i we have the ratio:
V=V0-R2i and in the case of low variations of E:
AV+AVo=R2Ai Emean V01tS 300 R1 -9" 1600 R2 ..Q 1000 imean 8.-- 55 Potential variations of E up to about can be balanced completely by means of this circuit arrangement.
Instead of using the glow discharge lamp L, use may of course be made of other impedances provided that their differential resistance is lower than R2 or than the diflerential resistance of the circuit element which would take the place of R2.
1. In combination with a source of direct current voltage subject to fluctuation and an electrical system provided with two pairs of energizing terminals, a first resistor and solely a. single glow lamp connected in series across said voltage source, a second resistor having a resistive value substantially less than the magnitude of the first resistor, said second resistor being connected in a series circuit with said first resistor and glow lamp between one pair of said energizing terminals, and said lamp and second resistor being connected in a separate series circuit between the second pair of energizing terminals.
2. In combination with a source of direct-current potential subject to fluctuation and an elec-- trical system provided with two pairs of energizing terminals, a circuit for balancing potential ing one of said two pairs of terminals in series with said second resistor to said glow lamp, and means connecting the other of said two pairs of terminals in series with said second resistor to said source of direct-current potential.
3. In combination with a source of direct-current potential subject to fluctuation and an electrical system provided with two pairs of energizing terminals, a circuit for balancing potential fluctuations at said terminals comprising a first resistor, a single potential-regulating glow lamp having a predetermined operating range connected in series with said first resistor to said source of potential, the resistance of said first resistor having a value at which at the mean potential value of said source of potential said glow lamp operates in a central portion of said predetermined range, a second resistor, means connecting one of said two pairs of terminals in series with said second resistor to said glow lamp, and means connecting the other of said two pairs of terminals in series with said second resistor to said source of direct-current potential, the resistance of said second resistor having a value at which the potential fluctuations appearing at said one pair of terminals are of equal magnitude but oppositely directed with respect to the potential fluctuations appearing at said other pair of terminals.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS FOREIGN PATENTS Country Date Great Britain 1943 Number Number