Low frequency sine wave generator circuit

Claim 2

A signal generator circuit for providing a waveform which progressively cyclically increases and decreases in finite steps, the circuit comprising: at least a first and second pulse-forming circuit each providing a repetitive alternating rectangular pulse output wherein, during each cycle, at least some of the pulses in the waveform produced by each pulse-forming circuit start from 0 volts and have amplitudes of both positive and negative values; the widths of the positive and negative pulses of each pulseforming circuit being different from that of the other of same so at least some of the pulses of one of the pulse-forming circuits have leading and trailing edges occurring at different instants of time than the other of same, each pulse-forming circuit producing a different number of positive and negative pulses over a cycle thereof than the other of same, and means for adding together the outputs of said pulse-forming circuits wherein the outputs thereof combine to provide a stepped waveform progressively cyclically Increasing and decreasing in value and having a greater number of steps than the number of pulse-forming circuits.

Claim 3

The signal generator circuit of claim 1 wherein the output of one of said pulse-forming circuits varies in value between zero and said positive and negative values within each half cycle while the output of another pulse-forming circuit varies only between zero and a value of one polarity within the same half cycle.

Claim 4

A signal generator circuit for providing across a pair of output terminals a waveform which progressively cyclically increases the decreases in finite steps, the circuit comprising: at least a first and a second pulse-forming circuit each providing a repetitive rectangular pulse waveform in which successive half cycles are mirror images of one another and comprising spaced pulses at least some of which extend from a 0 amplitude reference, the waveform of said pulse-forming circuits respectively comprising different numbers of such pulses each half cycle with the waveform having the greater number of pulses having narrower pulses of substantially smaller amplitude than that of the other waveform and comprising each half cycle spaced pulses occurring while the other waveform is 0, at least one pulse occurring while the other waveform presents a pulse and presenting a 0 output while the other waveform presents a pulse so the instantaneous summation of said waveforms provide a resultant output waveform which progressively cyclically increases the decreases in steps which are greater in number than the number of pulse-forming circuits, and means for adding together the waveforms produced by said pulse-forming circuits to provide said resultant output waveform at said output terminals.

Claim 5

A signal generator circuit for providing across a pair of output terminals a waveform which progressively cyclically increases the decreases in finite steps, the circuit comprising: at least a first and a second pulse-forming circuit each providing a repetitive rectangular pulse waveform in which successive half cycles are mirror images of one another and comprising spaced pulses at least some of which extend from a 0 amplitude reference, the waveform of said pulse-forming circuits respectively comprising different numbers of such pulses each half cycle with the waveform having the greater number of pulses having narrower pulses of substantially smaller amplitude than that of the other waveform and comprising each half cycle spaced pulses occurring while the other waveform is 0, at least one pulse occurring while the other waveform presents a pulse and presenting a 0 output while the other waveform presents a pulse so the instantaneous summation of said waveforms provide a resultant output waveform which progressively cyclically increases the decreases in steps which are greater in number than the number of pulse-forming circuits, and means for adding together the waveforms produced by said pulse-forming circuits to provide said resultant output waveform at said output terminals.

Claim 6

The signal generator circuit of claim 3 wherein the waveform produced by said pulse-forming circuit producing the greater number of pulses comprises pulses which vary in polarity each half cycle and the waveform produced by said other pulse-forming circuit comprises only one relatively wide pulse each half cycle.

Claim 7

The signal generator circuit of claim 4 wherein there is a point in said pulse-forming circuit producing the greater number of pulses where the amplitude of the pulses varying in polarity each half cycle are substantially identical to that of the pulse of the waveform at the output of the other pulse-forming circuit, and the pulse-forming circuit producing the greater number of pulses including a stepdown pulse transformer having a primary winding connected to said point in the same wherein the pulses vary in polarity each half cycle and a secondary winding connected directly in series with the output of the other pulse-forming circuit.

Claim 8

A signal generator circuit for providing a signal which progressively cyclically increases and decreases in finite steps, the signal generator circuit comprising: a source of DC voltage having a relatively low voltage output, a DC to DC converter circuit connected to the output of said source of DC voltage for providing a DC output voltage of substantially greater magnitude than said relatively low voltage output, first and second rectangular pulse-forming circuits connected to the output of said DC to DC converter circuit for respectively providing from the output of said converter circuit different rectangular pulse waveforms respectively comprising positive and negative going pulses of different width and varying between 0 and positive and negative values approximately equal to the output of said DC to DC converter circuit, and which waveforms when modified to have respectively different amplitudes provide a resultant waveform which progressively increases and decreases in steps, and a stepdown transformer having a primary winding coupled to the output of said pulse-forming circuit having the narrower pulses and a secondary winding connected directly in series with the output of the other pulse-forming circuit.

Claim 9

A signal generator circuit for providing a signal which progressively cyclically increases and decreases in finite steps, the signal generator circuit comprising: a source of DC voltage having a relatively low voltage output, a DC to DC converter circuit connected to the output of said source of DC voltage for providing a DC output voltage of substantially greater magnitude than said relatively low voltage output, first and second rectangular pulse-forming circuits connected to the output of said DC to DC converter circuit for respectively providing from the output of said converter circuit different rectangular pulse waveforms respectively comprising positive and negative going pulses of different width and varying between 0 and positive and negative values approximately equal to the output of said DC to DC converter circuit, and which waveforms when modified to have respectively different amplitudes provide a resultant waveform which progressively increases and decreases in steps, and a stepdown transformer having a primary winding coupled to the output of said pulse-forming circuit having the narrower pulses and a secondary winding connected directly in series with the output of the other pulse-forming circuit.

Claim 10

The signal generator circuit of claiM 6 wherein said rectangular pulse waveform of the pulse-forming circuit having the narrower pulses comprises each half cycle pulses of alternating polarity having said positive and negative values so the average current flow is at or near 0.

Claim 11

A signal generator circuit for providing a signal which progressively cyclically increases and decreases in finite steps, the signal generator circuit comprising: a source of DC voltage having a relatively low voltage output, first and second rectangular pulse-forming circuits connected to the output of said source of DC voltage for respectively providing from the output of said converter circuit different rectangular pulse waveforms respectively comprising positive and negative going pulses varying of different widths between 0 and positive and negative values approximately equal to the output of said source of DC voltage, and which waveforms when modified to have respectively different amplitudes provide a resultant waveform which progressively increases and decreases in steps, and a pair of step-up transformers having primary windings respectively coupled to the output terminals of said pulse-forming circuits and secondary windings coupled in series circuit relationship, the step-up ratio of the transformer associated with said pulse-forming circuit having the narrower pulses being less then the other of same, wherein the summation of the positive and negative going pulses induced in said windings will produce a progressively increasing and decreasing stepped waveform.

Claim 12

A signal generator circuit for providing a signal which progressively cyclically increases and decreases in finite steps, the signal generator circuit comprising: a source of DC voltage having a relatively low voltage output, first and second rectangular pulse-forming circuits connected to the output of said source of DC voltage for respectively providing from the output of said converter circuit different rectangular pulse waveforms respectively comprising positive and negative going pulses varying of different widths between 0 and positive and negative values approximately equal to the output of said source of DC voltage, and which waveforms when modified to have respectively different amplitudes provide a resultant waveform which progressively increases and decreases in steps, and a pair of step-up transformers having primary windings respectively coupled to the output terminals of said pulse-forming circuits and secondary windings coupled in series circuit relationship, the step-up ratio of the transformer associated with said pulse-forming circuit having the narrower pulses being less then the other of same, wherein the summation of the positive and negative going pulses induced in said windings will produce a progressively increasing and decreasing stepped waveform.

Claim 13

The signal generator circuit of claim 8 wherein said rectangular pulse waveform of the pulse-forming circuit having the narrower pulses comprises each half cycle pulses of alternating polarity having said positive and negative values, and the rectangular pulse waveform of the other pulse-forming circuit comprises each half cycle one or more pulses having only one polarity.

Claim 14

A signal generator circuit for providing a waveform which progressively cyclically increases and decreases in finite steps to resemble a sinusoidal waveform, the circuit comprising at least first and second signal generators each providing a square pulse alternating output where the pulse varies between zero and positive and negative values of the same magnitude, the positive and negative values +V2 and -V2 of the output of one of the generators being substantially greater than the positive and negative values +V1 and -V1 of the other generator, and summing means for adding together the outputs of said signal generators, the instantaneous values of the outputs of said generators changing at different times to provide the following simultaneously occurring pairs of outputs in the sequence indicated which are added together by said summing means: 0+0, 0+V1, +V2-V1, +V2+0, +V2+V1, +V2+0, +V2-V1, 0+V1, 0+0, 0-V1, -V2+V1, -V2+0, -V2-V1, -V2+0, -V2+V1, 0-V1, and 0+0, to provide a stepped waveform progressively increasing and decreasing in value.

Claim 15

A signal generator circuit for providing a waveform which progressively cyclically increases and decreases in finite steps to resemble a sinusoidal waveform, the circuit comprising at least first and second signal generators each providing a square pulse alternating output where the pulse varies between zero and positive and negative values of the same magnitude, the positive and negative values +V2 and -V2 of the output of one of the generators being substantially greater than the positive and negative values +V1 and -V1 of the other generator, and summing means for adding together the outputs of said signal generators, the instantaneous values of the outputs of said generators changing at different times to provide the following simultaneously occurring pairs of outputs in the sequence indicated which are added together by said summing means: 0+0, 0+V1, +V2-V1, +V2+0, +V2+V1, +V2+0, +V2-V1, 0+V1, 0+0, 0-V1, -V2+V1, -V2+0, -V2-V1, -V2+0, -V2+V1, 0-V1, and 0+0, to provide a stepped waveform progressively increasing and decreasing in value.

Claim 16

The signal generator circuit of claim 10 wherein V2 is 3V1 and there are only two of said generator circuits.

Claim 17

A signal generator circuit for providing a signal which progressively cyclically increases and decreases in finite steps to resemble a sinusoidal waveform, the signal generator circuit comprising: at least two bridge circuits each including two pairs of series connected current control means connected across the terminals of a source of DC voltage, each bridge circuit having a pair of output terminals at the juncture of the current control means of each of said pairs of current control means, a pair of signal generator output terminals, means connectIng said output terminals of the bridge circuits and said signal generator output terminals in mutual series circuit relation, signal means for cyclically rendering the noncorresponding current control means of the pairs of current control means of each bridge circuit conductive and nonconductive sequentially and in different combinations to produce different rectangular topped pulse output waveforms at the output terminals of the bridge circuits, which waveforms respectively comprise positive and negative going pulses of different widths so as to form a progressively increasing and decreasing stepped waveform, and each of said current control means of each bridge circuit being capable of conducting current in both directions, so the zero output condition of one bridge circuit or the flow of an out-of-phase inductive current will not block the flow of current to the output terminals of the generator circuit.

Claim 18

A signal generator circuit for providing a signal which progressively cyclically increases and decreases in finite steps to resemble a sinusoidal waveform, the signal generator circuit comprising: at least two bridge circuits each including two pairs of series connected current control means connected across the terminals of a source of DC voltage, each bridge circuit having a pair of output terminals at the juncture of the current control means of each of said pairs of current control means, a pair of signal generator output terminals, means connectIng said output terminals of the bridge circuits and said signal generator output terminals in mutual series circuit relation, signal means for cyclically rendering the noncorresponding current control means of the pairs of current control means of each bridge circuit conductive and nonconductive sequentially and in different combinations to produce different rectangular topped pulse output waveforms at the output terminals of the bridge circuits, which waveforms respectively comprise positive and negative going pulses of different widths so as to form a progressively increasing and decreasing stepped waveform, and each of said current control means of each bridge circuit being capable of conducting current in both directions, so the zero output condition of one bridge circuit or the flow of an out-of-phase inductive current will not block the flow of current to the output terminals of the generator circuit.

Claim 19

The signal generator circuit of claim 12 wherein each of said current control means comprises a unidirectional current control device which is arranged so the current for said source of DC voltage passes freely therethrough when said control means allows the same to conduct, and a rectifier device in parallel with the associated current control device arranged to pass current in the reverse direction.

Claim 20

The signal generator circuit of claim 12 wherein each of said current control means is a transistor with load and control terminals and having substantial gain in both directions of current flow through the load terminals, and said signal means include a source of voltage for selectively coupling positive and negative voltages to the control terminal thereof.

Claim 21

The signal generator circuit of claim 12 wherein said signal means operates said current control means of each bridge circuit to produce outputs which are of the same polarity or zero at any instant, so the resultant signal fed to the load is equal to or greater than the values of each output.

Claim 22

The signal generator circuit of claim 12 wherein there is a different source of DC voltage connected to said at least two bridge circuits with the voltage output of one of same being substantially greater than the voltage output of the other of same, and said signal means associated with the bridge circuit having the source of DC voltage having the lower voltage output operating the current control means each half cycle so the outputs of the bridge circuits varies from zero to voltages of opposite polarity while the outputs of the other bridge circuit is zero or a voltage of one given polarity.

Claim 23

The signal generator circuit of claim 12 wherein there is a different source of DC voltage connected to said at least two bridge circuits with the voltage output of one of same being substantially greater than the voltage output of the other of same, wherein the output of one of the bridge circuit associated with the source of DC voltage with the lower output is zero when said corresponding current control means thereof are both simultaneously conductive or nonconductive and +V1 and -V1 when the two different noncorresponding current control means are respectively conductive, and wherein the output of the bridge circuit associated with the source of DC voltage with the higher output zero when said corresponding current control means thereof are both simultaneously conductive or nonconductive and +V2 and -V2 when the two different noncorresponding current control means are respectively conductive, and said signal means of the bridge circuits operating the current control devices thereof each cycle of the output of the generator circuit to produce the following simultaneously occurring pairs of outputs of the two bridge circuits in the sequence indicated: 0+0, 0+V1, +V2-V1, +V2+0, +V2+V1, +V2+0, +V2-V1, 0+V1, 0+0, 0-V1, -V2+V1, -V2+0, -V2-V1, -V2+0, -V2+V1, 0-V1 and 0+0.