Patent US3618601A successfully refreshed from Google Patents.
US3618601A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Iontophoresis unit
Assignee: Individual
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Filing: 1969-10-16
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Granted: 1971-11-09
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Expires: 1989-10-16
Abstract
Abstract An iontophoresis unit comprising means for probing into a biological medium, the probing means providing a resistance load, a high-voltage source, a low-voltage, calibrated current source, and an amplifier. The amplifier includes an output junction and a summing junction between which the probe means is connected, first circuit means for connecting the summing junction to one side of the low-voltage source and second circuit means for connecting the output junction to one side of the high-voltage source.
Inventors
- 👤 Thatcher W Richardson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:49
CPC Classifications
A; A61; A61N; A61N1/00; A61N1/18; A61N1/20; A61N1/30
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
192 words
A unit for applying a linearly controlled current to a load, said unit comprising a high-voltage source, a low-voltage, calibrated current source, and a half-operational amplifier for connecting such a load to said sources, said amplifier including an output junction and a summing junction between which such a load can be connected, first circuit means for connecting said summing junction to one side of said low-voltage source, and second circuit means for connecting said output junction to one side of said high-voltage source, said amplifier including an output transistor, the collector electrode of which is connected to said output junction, said second circuit means including resistance means, said amplifier also including a field effect transistor, the source electrode of which is connected to the base electrode of said output transistor and the gate electrode of which is connected to said summing junction, said first circuit means including resistance means, and means for probing into a biological medium, such as a nerve cell, to apply such a current thereto, said probing means being effective, when inserted into such a medium, to provide such a load between said output junction and said summing junction.
Claim 2
Dependent Claim
192 words
A unit for applying a linearly controlled current to a load, said unit comprising a high-voltage source, a low-voltage, calibrated current source, and a half-operational amplifier for connecting such a load to said sources, said amplifier including an output junction and a summing junction between which such a load can be connected, first circuit means for connecting said summing junction to one side of said low-voltage source, and second circuit means for connecting said output junction to one side of said high-voltage source, said amplifier including an output transistor, the collector electrode of which is connected to said output junction, said second circuit means including resistance means, said amplifier also including a field effect transistor, the source electrode of which is connected to the base electrode of said output transistor and the gate electrode of which is connected to said summing junction, said first circuit means including resistance means, and means for probing into a biological medium, such as a nerve cell, to apply such a current thereto, said probing means being effective, when inserted into such a medium, to provide such a load between said output junction and said summing junction.
Claim 3
Dependent Claim
33 words
The unit of claim 1 in which said low-voltage source includes means for selectively establishing the current output thereof, whereby linearly controlled step increases of current can be applied to said summing junction.
Claim 4
Dependent Claim
62 words
The unit of claim 1 in which said low-voltage source includes a battery, a constant current circuit means connected in series with said battery, a plurality of precision resistors connected in series across said battery and said constant current circuit means, and switch means for selectively shunting certain of said resistors, thereby to apply selectively variable current values to said summing junction.
Claim 5
Dependent Claim
77 words
An iontophoresis unit comprising means for probing into a biological medium, said probing means providing a resistance load, a high-voltage source, a low-voltage, calibrated current source, and an amplifier, said amplifier including an output junction and a summing junction between which said probe means is connected, first circuit means for connecting said summing junction to one side of said low-voltage source, and second circuit means for connecting said output junction to one side of said high-voltage source.
Claim 6
Dependent Claim
77 words
An iontophoresis unit comprising means for probing into a biological medium, said probing means providing a resistance load, a high-voltage source, a low-voltage, calibrated current source, and an amplifier, said amplifier including an output junction and a summing junction between which said probe means is connected, first circuit means for connecting said summing junction to one side of said low-voltage source, and second circuit means for connecting said output junction to one side of said high-voltage source.
Claim 7
Dependent Claim
129 words
The unit of claim 4 in which said amplifier includes an output transistor having emitter, collector and base electrodes, a field effect transistor having source, drain and gate electrodes, said collector electrode being connected to said output junction and through said second circuit means to said one side of high-voltage source, said emitter electrode and said drain electrode being connected to the opposite side of said high-voltage source and to the opposite side of said low-voltage source, said source electrode being connected to said base electrode, and said gate electrode being connected to said summing junction and through said first circuit means to the said one side of said low-voltage source, and third circuit means for connecting said source electrode to the said one side of said high-voltage source.
Claim 8
Dependent Claim
49 words
The unit of claim 5 in which said output transistor is an PNP-transistor and said field effect transistor is an N-channel transistor operable in the depletion mode, and in which said one side of said high-voltage source is negative and said opposite side of said high-voltage source is positive.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-11-08 | 1975-05-10 | 1975-11-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-08 | 1979-05-10 | 1979-11-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-08 | 1983-05-10 | 1983-11-09 | $7700.00 | Window Closed / Lapsed |