Pulse generator

Claim 2

A pulse generator comprising a step-up transformer having a secondary winding for delivering an output pulse for muscle stimulation, said transformer also having primary winding, a low impedance DC source means for coupling to said primary winding, and a multivibrator switching circuit coupled to complete the circuit of said primary winding so that current from said source flows through said primary winding, said multivibrator switching circuit including a pair of active elements and an R-C time constant means therebetween causing said multivibrator to switch current through said primary winding in impulses of relatively short duration, separated by relatively longer intervals between pulses, to provide separate output pulses across said secondary winding.

Claim 3

The apparatus according to claim 1 wherein a terminal of the primary winding of said transformer is connected in series relation with a first of said active elements, a principal electrode of the remaining active element being returned to a tap on said primary winding.

Claim 4

The apparatus according to claim 1 wherein a terminal of the primary winding of said transformer is connected in series relation with a first of said active elements, a principal electrode of the remaining active element being returned to a tap on a voltage divider connected across said primary winding.

Claim 5

The apparatus according to claim 2 wherein said active elements comprise complementary transistors and said R-C time constant circuit comprises a capacitor coupled between said terminal of the primary of said transformer and the control terminal of the remaining transistor, and a resistor coupling the capacitor to a point of reference potential establishing a relatively long period between pulsations.

Claim 6

The apparatus according to claim 4 further including a charging circuit for said capacitor including diode means coupling the junction of said capacitor and said resistor to a terminal of said primary winding of said transformer other than the first mentioned terminal, wherein said diode means is adapted to conduct current in a direction for charging said capacitor through the first of said active elements and adapting said capacitor to interrupt conduction in the remaining active element to conclude a pulse.

Claim 7

The apparatus according to claim 1 wherein said low impedance DC source means comprises a DC voltage source and a capacitor coupled thereacross.

Claim 8

A pulse generator comprising: a DC source, a transformer having a primary winding connected to said DC source, said winding having a first terminal and a second terminal as well as a tap between said first and second terminals, said transformer having a secondary output winding, a multivibrator switching circuit comprising a first transistor connected to the second terminal of said transformer primary for returning said second terminal to said source, said multivibrator switching circuit further including a second transistor having a first principal terminal connected to said transformer tap and a second principal terminal coupled to the control terminal of the first transistor, and an R-C time constant circuit comprising a capacitor coupled between the second terminal of said transformer primary winding and the control terminal of said second transistor, said time constant circuit further including a resistor returning the control terminal end of said capacitor to a point of reference potential.

Claim 9

A pulse generator comprising: a DC source, a transformer having a primary winding connected to said DC source, said winding having a first terminal and a second terminal as well as a tap between said first and second terminals, said transformer having a secondary output winding, a multivibrator switching circuit comprising a first transistor connected to the second terminal of said transformer primary for returning said second terminal to said source, said multivibrator switching circuit further including a second transistor having a first principal terminal connected to said transformer tap and a second principal terminal coupled to the control terminal of the first transistor, and an R-C time constant circuit comprising a capacitor coupled between the second terminal of said transformer primary winding and the control terminal of said second transistor, said time constant circuit further including a resistor returning the control terminal end of said capacitor to a point of reference potential.

Claim 10

The apparatus according to claim 7 further including charging means for said capacitor including diode means coupled between said first terminal and the junction between said capacitor and said resistor.

Claim 11

The apparatus according to claim 7 further including diode means coupled across the primary of said transformer to reduce an output spike at the end of conduction through said transformer primary winding.

Claim 12

The apparatus according to claim 7 wherein said first transistor comprises an NPN transistor and said second transistor comprises a PNP transistor, wherein the collector of said first transistor is connected to the second terminal of said transformer primary winding, and the emitter terminal of said second transistor is connected to said tap, said R-C time constant circuit coupling the collector of the first transistor to the base of the second transistor, while circuit means couple the collector of the second transistor to the base of the first transistor.

Claim 13

The apparatus according to claim 7 wherein said resistor is variable to provide an adjustable pulse period.

Claim 14

The apparatus according to claim 8 including a variable resistor in series with said diode means to provide an adjustable pulse width.

Claim 15

The apparatus according to claim 7 wherein said R-C time constant circuit is adapted to provide pulses on the order of milliseconds in duration separated by periods on the order of 1 second.

Claim 16

A pulse generator comprising a multivibrator switching circuit including a pair of active elements, and tapped load means connected in series relation with a first of said active elements, a principal terminal of the remaining active element being returned to the tap of said load means, an R-C time constant circuit coupling said two elements for causing said multivibrator switching circuit to switch, said time constant circuit including a capacitor coupled from the junction of the first active element and the load means to the control terminal of the remaining active element, and a charging circuit for said capacitor coupling said capacitor to the remaining terminal of said load means.

Claim 17

A pulse generator comprising a multivibrator switching circuit including a pair of active elements, and tapped load means connected in series relation with a first of said active elements, a principal terminal of the remaining active element being returned to the tap of said load means, an R-C time constant circuit coupling said two elements for causing said multivibrator switching circuit to switch, said time constant circuit including a capacitor coupled from the junction of the first active element and the load means to the control terminal of the remaining active element, and a charging circuit for said capacitor coupling said capacitor to the remaining terminal of said load means.