Abstract: A fluid medium is used in a process for polishing all surfaces of plastic components made of a material which is insoluble or inert within that fluid medium unless subjected to a temperature at which the insoluble plastic would deform. The process, which is particularly suitable for polishing the internal surfaces of tubing components for medical equipment, includes applying a vaporized solvent at an elevated pressure to liquify or melt the insoluble plastic component surfaces without deforming the component, followed by solidifying or freezing the surfaces by removing the component from the presence of the vapors.

Abstract: The backup control circuit is used with a main control circuit for a kidney dialysis machine and is operable upon failure of the main control circuit to operate with a predetermined time period to cause closing of a dialysate operate valve and opening of a dialysate bypass valve and/or stopping of a blood pump when an aberrant condition in the dialysate conductivity, temperature, flow or negative pressure are sensed and/or when an aberrant condition of the arterial or venous blood pressure is sensed and/or excessive leakage of blood into the dialysate is sensed. The backup control circuit includes control circuitry for controlling operation of the back-up control circuit, the circuitry having input contacts coupled to sensor inputs to the main control circuit. A time delay circuit has an input coupled to the control circuitry and is operable to initiate a timing cycle for the predetermined time period upon receiving an error signal from the control circuitry.

Abstract: The control apparatus is used with a dual beam spectrophotometer in which light of variable frequency from a light source is split into two beams which are directed along first and second optical paths to a photosensitive device. The control apparatus comprises electric control, processing and memory circuits coupled to the spectrophotometer for receiving and storing signals therefrom such as an output signal indicative of the particular wavelength of the light beams at any point in time and a log difference signal indicative of absorbance. The circuits include a first memory and a second memory for receiving and storing the log difference signals and control and processing circuitry for manipulating the data stored in the memory circuits. A wavelength digital display, an absorbance digital display and a CRT are provided. The control and processing circuitry causes a graph of wavelength v.

Abstract: A fluorometric analyzer includes a head assembly wherein the photomultiplier tube and excitation lamp of the analyzer are received in respective cavities and a transparent test cell is provided to receive a liquid sample. A first optical passage is provided between the lamp cavity and the test cell, and a second optical passage at right angles to the first optical passage is provided between the test cell and the photomultiplier tube cavity. A manually rotatable shutter assembly concentrically disposed about the test cell includes apertures for allowing light to pass through the optical passages when the shutter is rotated to a first position, and for simultaneously blocking the passage of light through the passageways when the shutter is rotated to a second position. Rotation of the shutter is limited by a first guide pin, and a second guide pin provides a desired degree of friction between the shutter assembly and the head assembly housing.

Abstract: The vibration attenuation support assembly is utilized in a centrifugal liquid processing apparatus for supporting a rotor assembly, a non-rotatable arm fixed to and forming part of the support assembly and a prime mover and for attenuating vibrations created by an unbalanced mass in the rotating parts of the apparatus. The apparatus comprises a cabinet having sidewalls and a floor and a rotor assembly mounted on the support assembly mounted on the floor. Tubings are coupled directly between a source of the liquid outside of the rotor to receptacles within the rotor without the use of fluid seals and are supported from the stationary arm. The rotor assembly includes structure for guiding the tubings from the stationary arm to the rotor and a drive train mechanism and prime mover for rotating the tubings at a first speed and for rotating the rotor at a second speed twice the first speed.

Abstract: The assembly is utilized in a centrifuge device wherein a receptacle is received and held between first and second platens which are held within a platen holder fixed to the centrifuge device and in respective inner and outer parallel planes spaced radially outwardly from a vertical axis of rotation of the centrifuge device. The first platen is movable with one side wall of the holder about a generally horizontal axis extending along a lower edge of a second side wall of the holder. A latch mechanism provides for a toggle latching action between the walls as the latch mechanism is moved from an open position to a closed position. In one embodiment of the latch mechanism a handle is connected to a shaft journalled on the one side wall and mounts a plate on each end thereof with each plate having a pin extending therefrom that is rotated within a keeper member on an edge of the second wall to latch the platens in place.

Abstract: An improved peristaltic pump includes a pivotably mounted pressure plate which, together with the pump roller elements, defines the pump chamber. The pivotal mounting of the pressure plate facilitates accessibility to the pump chamber in order to simplify the pump tube loading and unloading procedures. The mounting system for the pressure plate includes a mechanically-advantaged four-bar linkage arrangement which automatically retains the pressure plate in either its fully open or fully closed position as a result of an over-center type locking construction. The pump also includes a mechanism for adjusting the volume flow rate characteristic of a pump tube. This is particularly adaptable for a dual-tube system wherein a predetermined volume flow rate ratio is to be achieved.

Abstract: A controller is disclosed for controlling the operation of selected electro-mechanical devices without the use of a microprocessor or similar computing machines. The controller includes a memory programmed to output a data word each time the memory is advanced to its next successive memory address. Responsive to the data word, an electro-mechanical device, identified by the data word, is actuated to perform its function. As the function of an electro-mechanical device is completed, a sensor develops a control signal for altering the internal count of a counter. The counter, in turn, advances the memory to its next address for outputting its next data word. The cycle continues as the memory is advanced through its addresses and selected electro-mechanical devices are successively actuated to perform their assigned functions.

Abstract: The input polarizer and the output polarizer of a spectrofluorometer are each mechanically identical except for the optical elements, and are constructed as modules which plug into a spectrofluorometer base. Each of the polarizer modules includes a polarizing filter that is rotatable and a self-contained motor drive for rotating the polarizing filter. Each of the motor drives comprises an electric motor mounted on the respective module, a pulley mounted on the respective module and rotatable with actuation of the electric motor, a loop coupling the pulley to the polarizing filter for rotation of the filter with rotation of the pulley, and means for enabling the filter to rotate exactly 90.degree. in opposite directions.

Abstract: The optical detector is particularly adapted for use with an apparatus for separating blood into its components and is of the type including a centrifuge for centrifuging whole blood to separate same into the components thereof and of the type wherein plasma is withdrawn from the centrifuge through a flexible, light transmitting tubing and the spillover of red blood cells into the plasma withdrawn is monitored by the optical detector. The optical detector comprises a block having a slot across the top face thereof, the inner portion of the slot having a width less than the outer diameter of the tubing which is received in the slot such that when the tubing is pressed into the slot, it is squeezed from a circular cross section to an oval cross section to present two flat portions of the tubing adjacent opposite sidewalls of the slot. A first cavity is situated in the block behing a first sidewall of the slot and a second cavity is situated in the block behind a second sidewall of the slot.

Abstract: A fuel delivery system for an internal combustion engine is disclosed. The system includes primary and auxiliary heating means for vaporizing a liquid fuel, vapor storage means, carburetor means including metering venturi means for mixing the vaporized liquid fuel with atmospheric air to provide a combustible air/fuel mixture and means for controlling the delivery of vaporized fuel to the carburetor means. The carburetor means may be connected to a conventional internal combustion engine intake manifold for eventual delivery of the combustible mixture to the combustion chambers of the engine. The vaporized liquid fuel delivery means of the system includes a variable orifice vapor delivery nozzle for modulating the vaporized fuel content of the air/fuel ratio of the combustion mixture.The auxiliary heating means are operative to provide an initial supply of vapor to a vapor reservoir upon start-up of the internal combustion engine.

Abstract: A mixing apparatus for mixing a vaporized liquid fuel with air to develop a combustible air/fuel mixture is described. A finned swirl inducing member having a centrally located aperture is positioned downstream from a metering venturi and upstream from a plain tube mixing section. The centrally positioned aperture is sized and spaced to allow passage of a stream of vaporized liquid fuel delivered to the low pressure zone formed by a metering venturi. The fin members of the swirler are operative to cause a swirl of the air stream passing through the metering venturi. The swirling air stream prevents any direct contact between the vapor stream and the relatively cool side walls of the mixing section while causing mixing action between the interiorly constrained vaporized liquid fuel stream and the inner portions of the air swirl.

Abstract: A vapor reservoir adapted for use in conjunction with a vaporized liquid fuel system for an internal combustion engine is disclosed. The reservoir includes a movable wall member cooperative with means defining a housing to establish a variable volume vapor storage space. The movable wall member is referenced to the pressure of the air immediately upstream from the intake to the air and fuel metering portion of the engine. The housing includes a generally downwardly depending condensate collecting and return section. Vapor delivery conduits are positioned within the housing and support a thermally floating finned member operative to disperse vapor delivered to the vapor reservoir. The movable wall member is provided with position sensing means operative to provide an input to an electrical circuit for controlling the rate of vapor delivery to maintain a predetermined quantity of vapor within the vapor space.

Abstract: A control and energization circuit for applying the vehicle alternator output directly to the resistive window heaters is disclosed. By disconnecting the alternator output from the vehicle battery, thereby temporarily interrupting the charging cycle of the battery, substantially the full alternator output may be applied to the window heaters to deice the vehicle windows.

Abstract: A system for controlling the application of heat energy to a ceramic exhaust gas sensor and for linearizing the output signal from the sensor. The system compares, electrically, the resistance of a conductive heater winding against a fixed reference and permits a flow of electrical current through the heater whenever the comparison indicates that the temperature of the heater is below the desired level. By periodically establishing a flow of electrical energy through the heater and terminating that flow whenever the heater temperature reaches the desired level, the temperature of the heater may be held at the desired level with great accuracy. In order to periodically reestablish the flow of electrical energy through the heater, the system further provides an oscillator arranged to reestablish current flow through the heater a fixed time period following termination of current flow through the heater.

Abstract: An electrically powered liquid fuel vaporizer including overtemperature protection is described. A plurality of thin walled fuel conduits or tubes are arranged in a bundle and are communicated at one end to a source of liquid fuel and at their opposite end to a vaporized liquid fuel reservoir. Each end of the fuel tube bundle is provided with one member of a pair of electrical terminals. One of the pair of electrical terminals is communicated to a solenoid operated switch which in turn is communicated to one terminal of electric power source. The other of the pair of terminals is communicated to the opposite terminal of the electric power source. An insulating sheath or housing means is arranged around the fuel tube bundle. One end of the housing means is fixedly attached to the fuel tube bundle in proximity to one of the pair of electrical terminals. The housing member is provided with a third electrical terminal which communicates with the solenoid.

Abstract: A bridge circuit for combination with a variable resistance sensor whose resistance may vary as a function of a sensed variable and also as a function of a parasitic variable such as, for example, temperature. The bridge circuit includes at least one variable resistance which varies as a function of the parasitic parameter and is relatively insensitive to the sensed parameter. The bridge circuit comprises a first leg incorporating the sensor resistor having a tap junction whose voltage varies as a function of the sensed parameter and of the parasitic parameter, a second leg including the parasitic parameter responsive resistance and having a voltage tap whose voltage varies only as a function of the parasitic parameter and a third leg interconnecting the first and second leg voltage taps and having a signal tap whose voltage varies only as a function of the sensed parameter.

Abstract: An exhaust gas sensor probe and its method of manufacture are disclosed. A tube of ceramic material is arranged to support a resistive type ceramic exhaust gas sensor within the cup-shaped cavity in the end portion of the tube. The tube is also provided with a generally continuous groove around the exterior of the cup-shaped end portion to support a heater wire in close heat conductive relation to the sensor ceramic wafer. The ceramic tube is fixedly received within a housing which may include for example sufficient electrical connective means in the form of electrical terminals to electrically communicate the sensor and the heater wire to an external source of electrical energy and/or a utilization means. The present invention also provides a heat retaining end cap member having an infrared reflective coating for assisting in the retention of heat for those resistive type sensor ceramics which require an operating temperature substantially higher than the temperature of their normal environment.

Abstract: An exhaust gas sensor probe and its method of manufacture are disclosed. A tube of ceramic material is arranged to support a resistive type ceramic exhaust gas sensor within the cup-shaped cavity in the end portion of the tube. The tube is also provided with a generally continuous groove around the exterior of the cup-shaped end portion to support a heater wire in close heat conductive relation to the sensor ceramic wafer. The ceramic tube is fixedly received within a housing which may include for example sufficient electrical connective means in the form of electrical terminals to electrically communicate the sensor and the heater wire to an external source of electrical energy and/or a utilization means. The present invention also provides a heat retaining end cap member having an infrared reflective coating for assisting in the retention of heat for those resistive type sensor ceramics which require an operating temperature substantially higher than the temperature of their normal environment.

Abstract: A system for plotting the total luminescence spectrum of a sample comprises a spectrofluorometer including excitation and emission monochromator stages having operating wavelengths dependent on applied stepping pulses, and an X-Y plotter having a marking pen synchronized for movement along X and Y axis with changes in the wavelengths of the monochromators. A control circuit generates pulses to incrementally step the emission monochromator and horizontally scan the marking pen. A level detection circuit monitors the output of the spectroflourometer and activates the pen upon attainment of a desired contour level. Limit circuitry incorporated in the control circuit momentarily actuates the excitation monochromator following each horizontal scan to increase the excitation wavelength for the subsequent emission scan to complete the plot.