Cardiac pacemaker

Claim 2

A heart stimulator adapted to be incorporated in a human body, comprising a battery, a plurality of transistors supplied by said battery, an impulse generator, including at least one of the said transistors, output means including another one of the said transistors, an input for said output means, means for supplying the output impulses of said impulse generator to the input of said output means, a resistor inserted between the collector of the transistor of said output means and one of the poles of said battery, a direct connection between the emitter of the transistor of said output means and the other pole of said battery, a pair of output terminals respectively connected with the collector and with the emitter of the transistor of said output means, a resonant circuit tuned to a predetermined frequency, rectifier means connected with said resonant circuit, and an output impedance for said rectifier means inserted in series with said resistor, said rectifier means being connected to said output impedance for generating a DC voltage thereacross, opposing the battery voltage, so that the operating voltage available for said output means is reduced by inducing oscillation in said resonant circuit at said collector from the outside.

Claim 3

A heart stimulator adapted to be incorporated in a human body, comprising a battery, a plurality of transistors supplied by said battery, an impulse generator, including at least one of the said transistors, output means including another one of the said transistors, an input for said output means, means for supplying the output impulses of said impulse generator to the input of said output means, a resistor inserted between the collector of the transistor of said output means and one of the poles of said battery, a direct connection between the emitter of the transistor of said output means and the other pole of said battery, a pair of output terminals respectively connected with the collector and with the emitter of the transistor of said output means, a resonant circuit tuned to a predetermined frequency, rectifier means connected with said resonant circuit, and an output impedance for said rectifier means inserted in series with said resistor, said rectifier means being connected to said output impedance for generating a DC voltage thereacross, opposing the battery voltage, so that the operating voltage available for said output means is reduced by inducing oscillation in said resonant circuit at said collector from the outside.

Claim 4

A heart stimulator adapted to be incorporated in a human body, comprising a battery, a plurality of transistors supplied by said battery, an impulse generator, including at least one of the said transistors, output means including another one of the said transistors, an input for said output means, means for supplying the output impulses of said impulse generator to the input of said output means, a resistor inserted between the collector of the transistor of said output means and one of the poles of said battery, a direct connection between the emitter of the transistor of said output means and the other pole of said battery, a pair of output terminals respectively connected with the collector and with the emitter of the transistor of said output means, a resonant circuit tuned to a predetermined frequency, rectifier means connected with said resonant circuit, and an output impedance for said rectifier means inserted in series with said resistor, said rectifier means being connected to said output impedance for generating a DC voltage thereacross, opposing the battery voltage, so that the operating voltage available for said output means is reduced by inducing oscillation in said resonant circuit at said collector from the outside.

Claim 5

A heart stimulator adapted to be incorporated in a human body, comprising a battery, an impulse generator, including a first transistor, having its emitter directly connected with a first pole of said battery, a first resistor inserted between the collector of said first transistor and the second pole of said battery, a second transistor having a conductivity type opposite to that of said first transistor, said second transistor having its emitter directly connected with said second pole, a second resistor inserted between the base of said first transistor and the collector of said second transistor, a third resistor inserted between the base of said second transistor and said first pole, a first condenser inserted between the base of said second tRansistor and the collector of said first transistor, fourth and fifth resistors connected in series between the collector of said second transistor and said first pole, an output means having input and output circuits, means for supplying impulses appearing at the junction between said fourth and fifth resistors to the input circuit of said output means, a pair of output terminals included in the output circuit of said output means, a resonant circuit, said resonant circuit being tuned to a predetermined frequency, rectifier means connected with said resonant circuit and an output impedance for said rectifier means, said output impedance being series connected with said battery in the collector circuit of said output means, said rectifier means being connected to said output impedance for generating a DC voltage thereacross opposing the battery voltage so that the operating voltage available for said output means may be reduced by inducing the oscillations in said resonant circuit from the outside.

Claim 6

A heart stimulator adapted to be incorporated in a human body, comprising a battery, an impulse generator, including a first transistor, having its emitter directly connected with a first pole of said battery, a first resistor inserted between the collector of said first transistor and the second pole of said battery, a second transistor having a conductivity type opposite to that of said first transistor, said second transistor having its emitter directly connected with said second pole, a second resistor inserted between the base of said first transistor and the collector of said second transistor, a third resistor inserted between the base of said second transistor and said first pole, a first condenser inserted between the base of said second tRansistor and the collector of said first transistor, fourth and fifth resistors connected in series between the collector of said second transistor and said first pole, an output means having input and output circuits, means for supplying impulses appearing at the junction between said fourth and fifth resistors to the input circuit of said output means, a pair of output terminals included in the output circuit of said output means, a resonant circuit, said resonant circuit being tuned to a predetermined frequency, rectifier means connected with said resonant circuit and an output impedance for said rectifier means, said output impedance being series connected with said battery in the collector circuit of said output means, said rectifier means being connected to said output impedance for generating a DC voltage thereacross opposing the battery voltage so that the operating voltage available for said output means may be reduced by inducing the oscillations in said resonant circuit from the outside.

Claim 7

A heart stimulator as claimed in claim 2 wherein said output means comprises a third transistor having the same conductivity type as said first transistor, having its emitter directly connected with said first pole and having its base connected with said junction, and sixth and seventh resistors connected in series between the collector of said third transistor and said second pole, said seventh resistor being included in said output impedance.

Claim 8

A heart stimulator as claimed in claim 3 further comprising a second condenser inserted between the collector of said third transistor and said conductor adapted to be connected with a ventricular heart electrode.

Claim 9

A heart stimulator as claimed in claim 3 wherein said resonant circuit comprises an inductance and a third condenser in parallel with said inductance, and wherein said rectifier is inserted between one end of said resonant circuit and one end of said seventh resistor, the other ends of said resonant circuit and said seventh resistor being directly interconnected.

Claim 10

A heart stimulator as claimed in claim 3 wherein said output impedance further comprises a fourth condenser in parallel with said seventh resistor.

Claim 11

In a heart stimulator adapted to be implanted in a living body and deliver stimulating pulses to the heart thereof, said stimulator including an output stage with a transistor and a first impedance connected in the collector circuit of said transistor, that improvement which consists of DC voltage generating circuitry including inductive means for receiving energy from a source external to said body, a first capacitor connected across said inductive means to form a resonant circuit therewith, a rectifier and a second capacitor connected in series across said resonant circuit, and a second impedance connected across said second capacitor and series connected with said first impedance in the collector circuit of said transistor, said circuitry generating DC voltage across said second impedance in response to said external source, thereby modifying the DC operating voltage for said output stage and the amplitude of said stimulating pulses.

Claim 12

In a heart stimulator adapted to be implanted in a living body and deliver stimulating pulses to the heart thereof, said stimulator including an output stage with a transistor and a first impedance connected in the collector circuit of said transistor, that improvement which consists of DC voltage generating circuitry including inductive means for receiving energy from a source external to said body, a first capacitor connected across said inductive means to form a resonant circuit therewith, a rectifier and a second capacitor connected in series across said resonant circuit, and a second impedance connected across said second capacitor and series connected with said first impedance in the collector circuit of said transistor, said circuitry generating DC voltage across said second impedance in response to said external source, thereby modifying the DC operating voltage for said output stage and the amplitude of said stimulating pulses.