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Publication numberUS3901214 A
Publication typeGrant
Publication date26 Aug 1975
Filing date26 Mar 1973
Priority date26 Mar 1973
Publication numberUS 3901214 A, US 3901214A, US-A-3901214, US3901214 A, US3901214A
InventorsJames L Taaffe
Original AssigneeBrotman Phillip
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Human resistivity sensing device
US 3901214 A
Abstract  available in
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

United States Patent 11 1 Taaffe HUMAN RESISTIVITY SENSING DEVICE Inventor: James L. Taaffe, Philadelphia, Pa, Assignee: Phillip Brotman, New York, N.Y,

Filed: Mar. 26, I973 Appl. No: 344,650

US. Cl. [ZS/2.1 Z; 324/62 R Int. Cl A6lb 5/05 Field of Search 128/21 Z, 241 R, 2.06 R;

References Cited UNITED STATES PATENTS Mathison 128/21 Z Mathison it 128/21 Z Wcidingcr ct a1 U 128/206 R [4 1 Aug. 26, 1975 3,426,150 2/1969 Tygart 128/2106 R 3,556,083 [/1971 Grichnik 128/21 Z 3,614,651 10/1971 Pasquier 128/21 R 3,648,686 3/1972 Payne 128/21 Z Primary Examiner-Richard A. Gaudet Assistant Examiner-Lee S. Cohen Attorney, Agent, or Firm-Peter L. Berger 1 1 ABSTRACT An electrical circuit which is capable of producing a varying signal output, either in frequency or amplitude which is responsive to the changing resistivity sensed on the skin of a subject. Electrodes are placed on the subject's body and as the surface resistance changes, an audible signal is produced which can aid the subject in relaxing.

2 Claims, I Drawing Figure HUMAN RESISTIVITY SENSING DEVICE This invention relates to a bio-feedback type device used to gauge the level of tension of a subject.

It is proposed to provide a unique and improved electrical circuit having extremely good reliability and good utilization to sense the anxiety levels of a subject by producing an audible sound which is reflective of the subjects state. Biasing means are provided to set a norm about which the audible tone will vary.

The attached FIGURE illustrates an embodiment of this invention.

The electrical circuit is comprised of electrodes and 12 attached to a gripping member 14 which is capable of being either in a flat position so as to be attached to a flat surface of the body, or circular so as to be attached to an extremity. Electrode 10 is connected to the base of a transistor 16 through a resistor 18 and through a fixed resistor 20 and a biasing resistor 22 to the emitter of transistor 16. The collector of the transistor is connected through a resistor 24 to an emitter terminal of a unijunction transistor 26 as well as to one end of a capacitor 28, the other end of which is connected to ground. One base terminal of the unijunction transistor is connected through a resistor 30 to one end of a speaker 32 coil 34 and to the emitter of transistor 16. The other end of speaker coil 34 is connected to the collector ofa transistor 36, the emitter of which is connected to ground while the base thereof is connected to the second base terminal of unijunction transistor 26.

The circuit functions in the following manner: electrodes 10 and 12 connect to various places on the skin of the body. The person using the instrument adjusts the range or biasing control by varying resistance 22 to a desired tone, such as many-frequency. As his body resistance decreases, the frequency of the tone increases thus signalling greater anxiety for lesser body resistance. Capacitor 28 is charged through transistor 16 at a rate controlled by resistor 22 which controls the amount of current produced by current source means formed by transistor 16. Unijunction transistor 26 is a triggering device which is caused to trigger when its threshold rate is reached. The rate at which the level is reached is set by biasing resistor 22 but will be varied as the body resistance sensed at electrodes 10 and l2 varies. This is due to the voltage divider formed by the body resistance and resistors 20 and 22.

The output of unijunction transistor 26 is coupled through amplifier means formed by transistor 36 to energize speaker 32 so as to produce an audible sound.

I claim:

1. Electrical circuit means capable of being connected to the human body and producing a changing signal in response to changes in the surface resistivity of the human skin comprising electrode means adapted to be placed on the skin, variable frequency means comprising a unijunction transistor having an emitter and a pair of base terminals, biasing means connected between said electrode means and said variable frequency means for setting a biasing level for said variable frequency means, said emitter being connected to said biasing means,

said biasing means comprising a transistor and a variable resistance controlling the amount of current produced by said transistor,

said transistor having a base resistor connected thereto, said electrode means being connected through said base resistor to the input of said transistor to control the amount of current produced thereby,

a collector resistor connected to the collector of said transistor, a capacitor connected through said collector resistor to receive said current of said transistor to be charged thereby, said capacitor connected to said emitter of said unijunction transistor to cause said unijunction transistor to be triggered into conduction,

said variable resistance and the resistance at the electrode means forming a voltage divider,

the connection between said voltage divider connected to said transistor through said base resistor and,

speaker means connected to receive the output of said variable frequency means to produce an audible signal representation of the frequency of the signal produced by said variable frequency means.

2. Electrical circuit means as set forth in claim 1, comprising amplifier means connected between the output of said unijunction transistor and said speaker means.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2684670 *1 Aug 195127 Jul 1954Mathison Volney GElectropsychometer or bioelectronic instrument
US2736313 *5 Oct 195428 Feb 1956Muriel N WarkentinElectropsychometer or bioelectronic instrument
US3316897 *21 Dec 19642 May 1967Teldix Luftfahrt AusruestungHeart monitoring device with filter for suppressing the frequency of an ambient a.c.power source
US3426150 *27 Sep 19654 Feb 1969Lockheed Aircraft CorpSystem for fm transmission of cardiological data over telephone lines
US3556083 *2 May 196819 Jan 1971Beckman Instruments IncApparatus for measurement of electrodermal phenomena
US3614651 *27 Jun 196919 Oct 1971Claude Marie PasquierExternal control of variable frequency oscillator
US3648686 *3 Jul 196914 Mar 1972Burlyl R PayneAudible psychogalvonometer
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4052978 *19 Jan 197611 Oct 1977Amado EugenioElectro-therapy apparatus
US4088125 *19 Nov 19769 May 1978Cyborg CorporationMethod and apparatus for monitoring skin potential response
US4109645 *17 May 197629 Aug 1978Sancio BacchelliDevelopment of instruments measuring body resistance to ion and ionophoresis applications
US4163936 *19 Sep 19777 Aug 1979Shufro Richard BAudible tester for alarm circuits
US4173217 *23 Nov 19766 Nov 1979Johnston Lyman CMassage apparatus
US4365637 *29 Sep 198028 Dec 1982Dia-Med, Inc.Perspiration indicating alarm for diabetics
US4451781 *20 May 198129 May 1984Sarah AndersonMoisture tester
US4580091 *2 Apr 19841 Apr 1986Delta Research LimitedContinuity tester
US4926880 *8 Nov 198822 May 1990MicrocurrentsMethod for relieving sinus and nasal congestion utilizing microcurrents
US5064410 *9 Jun 198612 Nov 1991Frenkel Richard EStress control system and method
US5385150 *29 Oct 199331 Jan 1995Ishikawa; KeihachiAcupuncture device
US682125427 Jun 200123 Nov 2004Institute Of Critical Care MedicineCardiac/respiratory arrest detector
US9770185 *6 Aug 201426 Sep 2017Verily Life Sciences LlcSharing a single electrode between skin resistance and capacitance measurements
US20160038055 *6 Aug 201411 Feb 2016Google Inc.Sharing a single electrode between skin resistance and capacitance measurements
WO1981000045A1 *3 Jul 198022 Jan 1981Dia Med IncPerspiration indicating alarm for diabetics
WO1984001516A1 *14 Oct 198326 Apr 1984Alan David BealeTranscutaneous electronic nerve stimulation equipment
WO1990011751A1 *4 Apr 199018 Oct 1990Keihachi IshikawaAcupuncture locating device
U.S. Classification600/547, 324/692, 128/905, 307/650
International ClassificationA61B5/00, A61B5/053
Cooperative ClassificationY10S128/905, A61B5/0531, A61B5/486
European ClassificationA61B5/48S, A61B5/053B