Abstract: The parts of a measuring sensor include an electrode mounted on a conductive body and insulated therefrom. Part of the electrical capacitance between the electrode and the body is determined by the dielectric constant and conductivity of the material in which the electrode and body are immersed. A screening band is provided along part of the length of the electrode so as to shield the electrode from the electrical effects of the material so that only selected levels of material will affect the capacitance.The sensor is ideal for use in enamelled steel vessels.

Abstract: A combination pH electrode uses an enameled steel structure. The reference electrode is replaceable and may be interchanged with a different type of electrode or a sealing plug.

Abstract: A dental apparatus retracts supply hoses connected to associated dental instruments. A coil spring is used within a housing. The hose is interposed between the windings of the spring. When the hose is extended, the radius of the coil contracts causing control switches to be activated. A ratchet engages dogs on the spring preventing unwanted retraction. Upon release of the ratchet, the coil spring expands drawing the hose into the housing.

Abstract: An enameled steel cone is the support for a heat sensitive resistor element. The resistive element is arranged upon the enameled base of the cone and with a layer of enamel. A hollow shaft extends from the apex of the cone. Wires connected to the resistive element are fed through the body of the cone and through the hollow shaft. The assembly may be enameled in place or otherwise secured to a prepared structure such as a enameled steel vessel or member.

Abstract: A pulp cap mixture is prepared from silver particles and a dental cement such as polycarboxylate cement. Provision is made to apply low intensity direct current through the material placed in proximity to the pulp tissue. Ionic silver is released which provides anti-bacterial action.

Abstract: Apparatus for use with an insufflator. During the first part of an inhalator cycle, a patient is connected to ambient air but during the latter part of the inhalator cycle the patient is connected to the insufflator. This enhances the desired exposure of the patient's upper airways to the product of the insufflator.

Abstract: A power supply for self-rectifying X-ray tubes controls filament current inversely to tube current. Although the tube current is passed only during alternate half cycles provision is made for symmetrical control of the filament current.

Abstract: Light passing through an etalon is divided into three beams, each beam being incident to the etalon at a different angle. Two of the beams are received by detectors which generates intensity representative signal for each beam. The difference between the beam intensities represents the error between the etalon's passband and the wavenumber of the received light.

Abstract: Apparatus for separating radiation due to Raman scattering from a background of fluorescence.A sample of freely rotating molecules is exposed to monochromatic radiation of a fixed plane polarization. The resulting Raman radiation will be strongly polarized while any fluorescence will be essentially non-polarized. Orthogonal components are sequentially received by a detector which responds with output signals. The difference in signals corresponds to the Raman intensity independent of fluorescence.

Abstract: A power supply and timing circuit for an X-ray tube capable of maintaining constant X-ray exposure values and stable peak plate voltage despite relatively large variations in the voltage of the source from which the power supply is fed. The cathode-to-plate current in the X-ray tube is varied responsively to changes in the voltage of the source, thereby varying the load on the high voltage transformer and holding its output voltage at a constant value despite changes in the source voltage. Changes in the cathode-to-plate current may be compensated for by the use of a milliampere-second integrator to time the exposure.

Abstract: Surgical and dental apparatus may be sterilized after implantation in the patient and caused to provide bactericidal effects in the tissue proximate to the apparatus. The apparatus contains silver or is silver coated. A positive current is applied to the apparatus which releases atomic silver into the volume surrounding the apparatus.

Abstract: A control circuit forelectrosurgical units establishes a particular output signal to patient electrodes in response to condition of the patient electrodes. The duty cycle of the output signal is reduced when the patient electrodes are not in contact with the patient so as to prevent unwanted cutting and the duty cycle is increased when both patient electrodes are in contact with the patient so as to maximize the coagulation effect.The invention includes method of adjusting coagulation power by varying the duty cycle and not the amplitude of the output signal.

Abstract: A capacitive probe for measuring fluid level has two electrodes, each of which forms a capacitor with a supporting conductive body. The first electrode is a vertical band which will yield a capacitive value dependent upon the dielectric constant, conductivity, as well as level of the fluid. The bulk of the second electrode is arranged at the lower end of the supporting body totally immersed in the liquid, and will yield a capacitance based on the dielectric constant and conductivity of the liquid, but substantially not the level of the liquid. A value indicating the liquid level independent of dielectric constant and conductivity may be obtained from the two capacitive values of the electrodes.

Abstract: A method for treating skin ulcers, infections and the like by eletrotherapy. Therapeutic low intensity direct current is applied to a patient by electrodes, at least one of which contains silver. The polarity of the direct current is reversed from time to time to prevent the accumulation of unwanted material upon the silver bearing electrode due to electrochemical action.

Abstract: The coils of an electromagnetic flowmeter are driven by a current waveform which is the equivalent of a composite of a sine wave and a square wave. The induced voltage is perferably sampled during steady state conditions but is at all times free of transient voltage spikes or error signals.

Abstract: A non-contact film sensor is provided for an automatic X-ray film loader. The sensor includes an infrared source having an output which is filtered to be outside the spectral sensitivity of the X-ray film. The sensor may be used to monitor a supply magazine and also to determine the presence of film in a film path.

Abstract: An electrode for use in low intensity direct current therapy of skin lesions and the like. The electrode contains silver from which silver ions are carried to the treatment site under the influence of direct current to provide a germicidal action at the lesion. The electrode may have a porous support structure and some of the silver may be chlorided. The electrode is maintaned in substantially direct contact with the treatment site while being saturated with an electrolyte similar to tissue fluids.

Abstract: Apparatus for the quantitative determination of organic carbon dissolved in water and aqueous solutions. A sample is exposed to ultraviolet radiation which oxidizes the carbon content of any organic material contained therein to carbon dioxide. The amount of carbon dioxide generated is measured by apparatus which eliminates interference from other substances.

Abstract: A capacitive probe for gauging the level of liquid within a reaction tank, or the like, in which the capacitive probe is formed by an electrode strip affixed to a pre-existing elongated member which projects into the reactor tank, wherein the tank and the strip define two electrodes of a capacitor.

Abstract: An X-ray detector for converting X-ray energy into electrical energy which contains a X-ray sensitive fluorescent screen optically coupled to a photovoltaic energy conversion cell. An electrostatic shield is provided at the input of said fluorescent screen to shield the detector from both background electrical noise and ambient light. Mechanical configurations and electrical flexibility make the detector particularly well suited for the control of panoramic X-ray machines.