Abstract: A lung ventilator particularly adapted for use in weaning patients from dependence thereupon and includes an exhalation conduit through which the gas exhaled by the patient is passed. Both the rate of flow of gas passing through the exhalation conduit during each individual exhalation phase, and the minute volume of exhaled gases are monitored. If, during any given exhalation phase, the minute volume of exhaled gases should fall below a chosen threshold, indicating that the patient fails to breathe adequately, the ventilator is triggered to perform a mandatory ventilation cycle. The ventilator is inhibited from delivering mandatory breaths, however, until the rate of flow of exhaled gas in a given exhalation phase has reduced to the point which indicates that exhalation has ceased.

Abstract: An all-pneumatic medical ventilator of the volume-limited type is provided with a pneumatically driven drug nebulizer for injecting medication into the patient's breathing circuit in response to a cyclic pressure signal from the ventilator. The nebulizer is driven either directly or indirectly, according to the desired mode of use, from the pressurized oxygen source of the ventilator. In a preferred mode, a given portion of the tidal volume of gas is temporarily withdrawn from the breathing circuit during inhalation and subsequently forcibly returned by way of the nebulizer to the breathing circuit. This takes place during the same inhalation period so that nebulized medication is added to the patient's breathing circuit without changing either the predetermined oxygen concentration or tidal volume of the breathing gas.

Abstract: A system is disclosed for providing an interconnection between two needle valves such that movement of either needle valve, in opening or closing thereof, is affected or limited by movement of the other valve. The invention is particularly suited to an anesthesia machine wherein separate supplies of oxygen (O.sub.2) and nitrous oxide (N.sub.2 O) are fed to individual needle valves which are then individually adjusted to provide a desired mixture of N.sub.2 O and O.sub.2 for administration to a patient to anesthetize the same. The system herein disclosed interconnects the individual needle valves such that the O.sub.2 needle valve may be opened fully without restriction, however, when the N.sub.2 O valve is open, the interconnection provides that closing of the O.sub.2 valve will, at a predetermined point, also correspondingly close the N.sub.2 O valve, thus preventing the percentage of N.sub.2 O in the mixed gas from raising above a set value, i.e.

Abstract: A selector valve for providing a choice of one of two vaporizers for use in administering an anesthetic to a patient is disclosed in connection with a manifold for receiving the vaporizers.The selector valve has three positions, wherein the user can utilize one of two vaporizers or place the valve in an off position when neither vaporizer is in the circuit providing a flow of gas to the patient.One of the features comprises a positive position means where the selector valve cannot inadvertently be placed in any position intermediate any two of the three positions so that only one of the three defined positions may be selected. Also, in the off position, leakage is prevented into the gas stream to the patient of anesthetic vapors from either of the vaporizers mounted to the manifold by closing both the inlet to and the outlet from both such vaporizers.

Abstract: A radial inflow turbine is disclosed utilizing a star wheel type of blade and wherein the inlet nozzles are located along the sides or lateral of the blade tips rather than located radially beyond the blade tips. The side approach enables the turbine to include an annular chamber outside of the moving blades and where small particles are centrifuged during operation and collected. The incoming hot gases, that propel the blades, pass through approximately a 90.degree. turn and continue radially inwardly. The large particles hit the turbine blades and are projected outwardly into the annular chamber for collection and subsequent removal while the smaller particles may be centrifuged in the stream of gas and immediately thrown outwardly. The turbine is capable of removing particles to as small as 2-3 microns (.mu.m).

Abstract: A liquid-vapor converter of a compact skid-mounted design is provided that efficiently converts a cryogenic liquid into a vapor, and which includes, in the same skid mounting, all necessary components necessary to receive the liquid and to provide therefrom a high pressure source of gas, particularly for use in recovery of product from oil wells. The design includes an internal combustion engine as a motive force to drive the main pump for pressurizing the vapor for its intended use. A heat exchanger receives the liquid and circulates the same through tubing, where the liquid is vaporized in the heat exchanger by ambient air being passed across the tubing to warm the liquid, thus effecting such vaporization. The heat exchanger utilizes heat from the engine exhaust to preheat the incoming ambient air prior to its passing in heat transfer relationship across the tubing.

Abstract: A system is disclosed for detecting the position of the pointer of a gauge. The system includes a stationary light source which is positioned adjacent the pointer. A lens receives the light from the light source and redirects the light in at least one elongated light beam directed toward the pointer. In the preferred embodiment, the light source is located along the pointer's axis of rotation and the lens bends the light rays 90.degree. to form at least one arcuate light beam. A plurality of elongated light beams can be used and variations of different shapes of light beams can readily be used by so designing the lens means. A light sensitive detector is positionable in the gauge itself and is movable along a guided path on the opposite side of the pointer than is the light source. The guided path generally follows the particular shape of light beams that is directed toward the needle.

Abstract: Improved nebulizing apparatus is disclosed for generating a heated liquid-dispensed-in-gas mist for administration to a patient undergoing aerosol therapy. The apparatus includes a novel fastening means for attaching a heater unit to the underside of a reservoir containing the liquid. The heater unit is easily attached and detached and yet enables good heat conductivity for heating the liquid within the interior of the reservoir. The bottom of the reservoir itself includes a concave heat conducting surface which, in operation, is in direct contact with the surface of the heater unit. The fastening means includes at least two draw clips which extend upwardly from the heater unit and which engage the reservoir to effect the desired fastening. By an adjustment of the draw clips with respect to the heater unit, the heat conducting surface of the reservoir can be forced out of its concavity to a flat, planar shape in good surface contact with the heater to enhance heat conductivity to liquid within the reservoir.

Abstract: A double valve construction for gas or vacuum outlets which are operable by the insertion of an adapter to deliver gas or vacuum to an intended use including a secondary housing which is connected to the gas or vacuum and has a secondary valve. A primary housing is adapted to interfit with the secondary housing such that the secondary valve is opened but allowing the two housings to be adjustable for varying plaster thicknesses of the wall in which the outlet is mounted. The primary housing has a dust cap closing its delivery end. A primary valve is formed by the interrelationship of the primary housing into the secondary housing and normally prevents the gas or vacuum from reacting the primary housing. As an adapter is inserted into the primary housing, the dust cap is displaced a predetermined distance until it opens the primary valve allowing the gas or vacuum to enter the adapter.

Abstract: The invention relates to an insulated-gate field effect transistor which is adapted for detecting and measuring various chemical properties such as ion activity in a solution. The device has a chemically sensitive layer which overlies a portion of a substrate other than that covered by the gate insulator. When this chemically sensitive layer is exposed to a solution or other substance, the electric field in the substrate is modified which changes the conductance of the channel between a source region and a drain region. The change in conductance is related to the chemical exposure and can be detected with a current meter.

Abstract: A gas humidifying device is disclosed which includes a generally enclosed chamber defining a water reservoir, and an umbrella-shaped member positioned in the chamber with its downwardly facing peripheral edge normally extending beneath the surface of the water in the reservoir, whereby the interior of said member defines a gas accumulation space in contact with the water surface. Gas inlet means are connected to the gas accumulation space for introducing a dry gas to be humidified; and gas outlet means are connected to the chamber, and communicate with the chamber which is external to the gas accumulation space within the unbrella-shaped member. At least portions of the peripheral edge of the umbrella-shaped member are upwardly displaceable from the normal position to a position above the water surface and such displacements intermittently occur as pressure builds up in the gas accumulation space in consequence of gas flow proceeding to such space from the inlet means.

Abstract: A method is disclosed for making a cuff or balloon for use with an endotracheal tube by means of a cold parison blow molding process. The method may be utilized for large quantity production of such cuffs yet affords reliable control of the thickness throughout the cuff. In carrying out the method, a thermoplastic or other elastomeric tube of predetermined dimensions and elasticity is prestretched a predetermined amount in the longitudinal direction. The tube is positioned within a hollow mold or, for quantity production in a series of such molds, having the mold internal configuration in the general shape of the desired end balloon form. The mold or molds are vented to atmosphere. Pressure is applied to the interior of the tube and such predetermined pressure is retained within the tube. The tube and mold(s) are then heated such that the tube softens and expands under the pressure to assume internal configuration of the mold(s).

Abstract: A carbon-dioxide (CO.sub.2) snow-making system comprising a snow horn having an upper chamber into which pairs of jets of CO.sub.2 are transversely injected from opposite directions, respectively. The expanding jet mixtures of snow and vapor are directed into collision along paths that lie generally in a single plane so as to intersect at an angle of 180.degree. in a central region of the chamber, thereby to dissipate the kinetic energy of the jets. Where more than two jets are directed into collision at a common point, the intersecting angles are so chosen that the resultant kinetic energy is substantially zero. High velocities and turbulence of the snow-vapor mixture are thereby minimized, and the snow discharges evenly from the chamber and through the horn without sticking thereto for uniform distribution.

Abstract: A fast-freeze system comprises an insulating housing for a product conveyor of the vertical helix or spiral-type wherein the upper and lower loops (or tiers) respectively, of the helix discharge or receive the product, as the case may be, at product openings (or ports) in the housing; a multiple-spray nozzle array on a header receives a regulated supply of liquid nitrogen according to a preset freezing temperature through a modulating servo-valve control; the header subtends a restricted sector only of an upper conveyor tier for producing heat transfer by direct liquid nitrogen-to-product contact to establish a single very cold zone substantially in advance of the discharge port, and the exhaust nitrogen vapor is discharged by blower action through the product entrance port.

Abstract: This disclosure is directed to novel ethers of the formula:CF.sub.3 CH.sub.a X.sub.b --O--CF.sub.2 CH.sub.c F.sub.d Cl.sub.ewherein X is fluorine, chlorine or bromine, preferably fluorine, a is 1 or 2, b is 0 or 1, a plus b are 2, preferably both a and b being 1, c is 0 or 1, d is 0 to 2, e is 0 to 2, c plus d plus e are 3, preferably each of c, d, and e is 1, and a plus c are 1 or 2, preferably 2, with the proviso that when e is 1 or 2, X is fluorine or bromine, preferably fluorine. The compounds having less than eight fluorine atoms per molecule are useful as anesthetics, and all of the compounds are useful as solvents and dispersants for fluorinated materials. A highly preferred compound useful as an anesthetic is 1,2,2,2-tetrafluoroethyl 1',1',2'-trifluoro-2'-chloroethyl ether.

Abstract: Anesthetic vaporizer of the flow-through type having a calibrated flow control valve unit for proportional distribution of the inlet gas between a vaporizing chamber and a main bypass passage to obtain a desired anesthetic concentration. A rotary, multiple-port valve with a multiplicity of laminar flow-type passages in parallel is operable in discrete steps for adding the anesthetic vapor from the chamber in predictable increments to a preset flow of the inlet gas for proportional gas division. An auxiliary gas bypass for temperature compensation has a cone-type valve with restricted opening controlled by a temperature responsive motor in the vaporizing chamber. A wick assembly in the anesthetic vaporizing chamber guides the chamber gas through a multiplicity of parallel passages formed by stacked sheets of absorbent and corrugated materials respectively, to obtain maximum vaporization of the anesthetic.

Abstract: This disclosure is directed to novel ethers of the formula:CF.sub.3 CH.sub.a X.sub.b --O--CF.sub.2 CH.sub.c F.sub.d Cl.sub.ewherein X is fluorine, chlorine or bromine, preferably fluorine, a is 1 or 2, b is 0 or 1, a plus b are 2, preferably both a and b being 1, c is 0 or 1, d is 0 to 2, e is 0 to 2, c plus d plus e are 3, preferably each of c, d, and e is 1, and a plus c are 1 or 2, preferably 2, with the proviso that when e is 1 or 2, X is fluorine or bromine, preferably fluorine. The compounds having less than eight fluorine atoms per molecule are useful as anesthetics, and all of the compounds are useful as solvents and dispersants for fluorinated materials. A highly preferred compound useful as an anesthetic is 1,2,2,2-tetrafluoroethyl 1',1',2'-trifluoro-2'-chloroethyl ether.

Abstract: A ceramic crystal transducer is connected to a direct current supply in series with a pair of transistors. A pair of independent multivibrator oscillators are connected, each controlling one of the transistors. Each oscillator establishes a rectangular wave and is provided with a continuously adjustable resistor for controlling the output frequency of the corresponding oscillator. The one oscillator is constructed to produce a frequency and a voltage to excite the crystal at the order of the natural resonant frequency and to thereby produce an audio output signal. The second multivibrator oscillator selectively controls the second transistor to control the on/off or pulsing rate of the tone related audible signal. The crystal is pulsed at the output rate of the tone oscillator and vibrates at the fundamental frequency of the rectangular wave as well as harmonics to either side of such fundamental frequency to produce a full and pleasant sound.

Abstract: An automatic switchover valve is described having a unique venting system whereby any areas which may cause a buildup in pressure during shuttling are normally vented to atmosphere. The shuttle is of a simple, easy to manufacture design having a central inwardly tapered portion which allows communication with internal parts of the valve to atmosphere. The valve also features sealing means which seal against moving surfaces without being subjected to rubbing on sharp surfaces or orifices, thus prolonging seal life.

Abstract: A tracheal tube adapted for insertion into the trachea of a patient for introducing or removing gas. The tube includes a main inflatable cuff which surrounds the distal end of the tube. A gas passageway communicates at one end with the interior of the cuff, and the other end of the passageway is adapted to receive an inflating means, for delivering gas to inflate the cuff. The gas passageway includes a check valve, and a generally oval pilot balloon is in gas communication with the cuff via the passageway. The pilot balloon is longitudinally pre-stretched between its opposite end portions by means maintaining the pre-stretched condition. Accordingly the balloon in its non-inflated condition is characterized by a series of mutually spaced folds, extending longitudinally between the opposed ends. The ridges of the folds contrast with the troughs between folds, to provide a series of spaced, visually discernible markings which visually signal the non-inflated condition of the main cuff.