Abstract: A mixer for liquids and liquid suspensions has a motor drive and housing which is portable and can be carried from tank to tank and attached to the tank where mixing is carried out. The housing depends from the yoke and contains a quill which is driven by the motor drive. A chuck mechanism is associated with the housing and quill to enable mixer impeller shafts to be held in assembled relationship in the mixer and readily removed and replaced with shafts having impellers specially adapted for the particular mixing application of interest. The chuck mechanism is operable even though the quill is hidden in the mixture housing.

Abstract: A system for long term releasing of medication in the mouth, and especially an intra-oral fluoride releasing system (IFRS) for releasing fluoride over a long term for inhibiting the formation of caries in the teeth. The system uses a holder for retaining and protecting intra-oral fluoride tablets or other intra-oral medicament in the form of fluoride releasing devices (IFRD). The holder has a plate with retaining sides and retaining posts or a carrier. The tablet will fit within the holder. The tablet may be located in the carrier, or ligature bands can be tied around the tablet in order to releasably hold the IFRD within the holder. The system causes a level of fluoride to be maintained over a long term within the mouth which has been found chemically effective for caries control and without causing severe irritation to oral tissues.

Abstract: A hologon scanning system which provides two sequential scans across an image plane per revolution of the hologon. The hologon is a disc having a single facet with a planar linear diffraction grating in a surface which is perpendicular to the axis of rotation of the disc and which is centered on the axis of rotation. An incident laser beam which preferably overfills the facet is diffracted and scanned by the rotation of the facet. The facet is preferably elliptical in shape with its major axis perpendicular to the facet grating lines. The diameter of the disc can be made only slightly larger than the profile of the incident beam on the disc so as to minimize inertia and enable the disc to be rotated at very high speeds without failure due to centrifugal force induced stress. Four sequential scans per revolution can be produced by using a pair of superimposed centered facets with their grating lines oriented orthogonally to each other.

Abstract: A mixer impeller made up of paddle shaped blades, which near their tips (e.g., at 90% of the radius of the impeller from its axis of rotation) are of a width at least 40% of the impeller's diameter. The blades also having camber and twist. They are formed by establishing bending moments which form the blades into sections which are curved and flat, with the flat sections being at least in the center area of the base of the blades.

Abstract: In an SSD (smoothing by spectral dispersion) system which reduces the time-averaged spatial variations in intensity of the laser light to provide uniform illumination of a laser fusion target, an electro-optic phase modulator through which a laser beam passes produces a broadband output beam by imposing a frequency modulated bandwidth on the laser beam. A grating provides spatial and angular spectral dispersion of the beam. Due to the phase modulation, the frequencies ("colors") cycle across the beam. The dispersed beam may be amplified and frequency converted (e.g., tripled) in a plurality of beam lines. A distributed phase plate (DPP) in each line is irradiated by the spectrally dispersed beam and the beam is focused on the target where a smooth (uniform intensity) pattern is produced. The color cycling enhances smoothing and the use of a frequency modulated laser pulse prevents the formation of high intensity spikes which could damage the laser medium in the power amplifiers.

Abstract: Mixer apparatus including a high horsepower motor and transmission drive for an impeller, together with associated shafts, impellers and a bearing and seal assembly, are supported on a tank without excessive loading and vibration of the top head of the tank and without special construction to support the apparatus from the foundation. The support structure of the mixer apparatus is provided by a machine base having connected beams on which the motor and the transmission (gear box) are located. A noise containment enclosure on the base may be used to lower radiated noise levels. The impeller shaft and shaft extensions thereof are disposed in telescoping relationship with the transmission, aligned along the same axis. The machine base is parallel to the foundation and is supported on vertical columns, which depend from one end of the base and from opposite ends of a cross beam at the other end of the machine base.

Abstract: A computer workstation for supporting and positioning a computer and/or its video display terminal or screen and its keyboard at minimum fatigue locations. The computer and/or the video display terminal can be located at a desired elevations and tilted. The keyboard is supported on a keyboard shelf which can also be positioned at a desired elevation and tilted. The computer table and shelf are located between side wall panels of a frame having racks with slots at different elevations. Both the keyboard shelf and the computer table are pivotally mounted on members which can be positioned in different ones of the slots to select the elevation thereof. A belt connected at one end to the frame extends around a pulley under the computer table so as to support the table. The belt has holes which are engaged by a hook on a handle which is pivotally mounted to the bottom of the table. By pivoting the handle the length of the belt underneath the table can be changed thereby tilting the table.

Abstract: A portable personnel monitor that is easily transported, set up and operated to perform radiological contamination testing of personnel is provided by a collapsible frame containing scintillation detectors. The frame has hinged columns as side members and a top member which is releasably connected with electrical and mechanical connecting and alignment devices to the columns. A signal analyzer unit is attached to one column via a T-slot and is connected to the scintillator detectors via a coaxial cable. A base plate having upstanding posts supports the frame rigidly in an upright position and is releasably connected to the columns by push/pull pins. The frame defines a passage which is of sufficinet height so that an adult human subject can pass through the radiation sensitivity field defined by the detectors.

Abstract: A strain relief member of sheet metal is disposed within the housing of a modular connector having a locking bar which ordinarily is crimped into locking engagement with the wires of a multi-wire cable. With such an arrangement flexure of the wires occurs at the locking bar and the wires break thereby breaking the connection provided by the connector to equipment connected to the cable. The strain relief member has a tray portion over which the wires extend to contacts located near one end of the housing. A stem extends rearwardly from the tray portion out the housing and has arms which are crimped around the cable thereby providing strain relief. The tray has a slot therein which is disposed in alignment with the locking bar. When the locking bar is crimped, it fastens the strain relief member to the housing.

Abstract: A system enabling the frequency, and if desired, phase control of an oscillator which generates a standard signal useful as a carrier which is modulated by modulation signals. A multiplicity of such oscillators and associated transmitters may be used in a simulcast transmission system. The transmissions originate from a station which may be remote from the transmitters. The station has a system controller and the transmitters have transmitter controllers. For frequency control a reference signal generated in the system controller is transmitted over the same link and band width (e.g. the voice band width) with the voice modulating signals to the transmitter controllers of all of the transmitters.

Abstract: A perforated paper feed mechanism such as a tractor has an optical system for detecting the presence of the form and particularly the motion of the form and utilizes a reflector which may be mounted on the lid of the tractor at one end of the tractor (where the paper enters or leaves the tractor). The optical system may be implemented by a prism which folds the path of light from a light source (an LED) to a photo detector (a photo-transistor) the path is aligned with the perforations in the paper. Since the perforations are spaced, the photo transistor provides a train of pulses as the paper is fed by the tractor. A pulse detector responds to the presence or absence of pulses within a given period of time comparable to the time when perforations are fed past the optical path. An output from the detector thus indicates whether the paper is in motion and is being fed by the tractor. Failure to receive pulses indicates either the absence of paper (paper out) or a jam in the feed.

Abstract: In order to drive the RF lines (electrodes) of an ion projection printing head or cartridge, driver circuits are provided which generate high voltage, radio frequency signals with rapid envelope rise and fall times so that dots of varying density in accordance with a gray scale may be formed on a rapidly moving dielectric surface. A separate RF driver circuit for each line includes an active switching device, preferably an FET. A series resonant circuit is connected across the active device. This circuit is provided by an inductor connected in series with the effective capacitance presented by the RF electrode of the ion projection head which is being driven. The inductor and effective capacitance defines a series resonant circuit.

Abstract: A harvesting machine is especially adapted for automatic topping and loading of crops, such as onions. The crops are gathered from the field and elevated on a conveyor to a region adjacent to which a topping device (a sickle) is disposed. The conveyor has openings to permit the passage of air which is blown from a blower. The openings are sufficiently narrow to support the crop while allowing rocks, clumps and other debris to drop therethrough. The blower is offset from the topping region. A duct extends tangentially and upwardly from the blower to direct a laminar (non-turbulent) flow of air through the conveyor openings for extending the tops. The duct has a wall at the bottom thereof which faces the region. This wall has a passage, preferably with louvers which extend generally vertically. A negative pressure is developed adjacent to these louvers and a generally laminar flow of air passes upwardly through the louvers and enhances the laminar flow through the conveyor in the region where topping occurs.

Abstract: Single-turn loop-gap solenoidal resonators for establishing RF fields (B.sub.1) transverse to the static B.sub.0 field of a magnetic resonance imaging system. Tubular forms of dielectric (plastic) material have conductive foil bands attached to their outside walls with one or more gaps between the ends of the bands and provide solenoidal signal-turn coils. A circuit resonant at radio frequencies is defined by the inductance of the solenoidal coils formed by the bands and the capacitance across the gap. The resistors and/or capacitors spaced along the axis of the tubular bodies tune the circuit and provide RF magnetic field homogeneity within the structure. Holes in the sides of the forms through the bands provide for the entrance of the analytical sample of body mass of a subject (the head, shoulder, hand, foot, knee or elbow).

Abstract: Bar code readers using laser diodes conserve electrical power and limit output laser radiation to levels required by governmental regulation (1 milliwatt average power) by utilizing a laser diode having a output optical power vs laser current characteristic which has a slope efficiency (the ratio of the change in power to the change in current, .DELTA.P/.DELTA.I, which is less than 1 in the region where stimulated (laser) emission occurs. The laser is operated with current pulses having a duty cycle less than 100%, and preferably in the range from 50% to 20% in the stimulated emission region of its characteristic, such that the average output laser power does not exceed the level required by government regulations (1 mw) while the laser output during the pulses is greater than 1 mw.

Abstract: Miniature scan modules which occupy a volume of less than about 1 cubic inch so as to facilitate installation in any apparatus which requires scanning of a light beam across a target and detection of light reflected from the target. The miniature size of the scan module enables it to be incorporated in various apparatus, such as keyboards or terminals and provide them with the ability to read various symbols, particularly bar codes. The module has at least two printed circuit boards on at least one of which a source of a light beam, such as a laser diode or light emitting diode is mounted and another board which may be fixed in the apparatus in which the module is installed. The boards are interconnected by structure including a flexure which defines a pivot axis for the light source and the board on which it is mounted. The flexure is made up of a plurality of elements which are insulated from each other and provide separate conductive paths for electrical power and signals between the boards.

Abstract: A diffractive imaging lens, has a diffractive optical element and an aperture stop remote from the lens in the direction of the object to be imaged which corrects the lens for coma, astigmatism, and field curvature and which can be corrected for spherical aberration by using a phase corrector in the aperture of the stop. The lens system may be provided in anamorphic configuration.

Abstract: A system for measuring the thermal characteristic of the surface-lattice of solid state materials with picosecond time resolution uses a picosecond laser pulse which is synchronized with a picosecond electron pulse; the electron pulse being generated by splitting the laser pulse into two beams one of which interacts with the surface under test and the second activates the cathode of an electron gun creating an electron pulse which is, collimated, focused and incident at a small acute angle (1-3 degrees) on the surface. The electron pulse generates a reflection high energy electron diffraction pattern (RHEED) which provides information on the surface temperature in accordance with the Debye-Waller effect. Time resolved measurements are made by using electron pulses which are delayed with respect to the laser pulses by successively greater time intervals.

Abstract: A three phase voltage regulator system uses a transformer having primary, secondary and tertiary windings for each phase which are closely magnetically coupled to each other and are connected to provide a four wire (wye) three phase output on three hot lines with a neutral line, and a three phase input which is also wye connected, but where the neutral need not be connected to an input neutral line. The voltage across each primary phase winding is regulated by a series connected regulator circuit. The regulator circuit may derive voltages from the respective tertiary winding which either bucks (subtracts from) or boosts (adds to) the input voltage so as to maintain the primary winding voltage substantially constant. A controller which is responsive to the output voltage from the secondary windings controls the regulators and responds to output voltages of their respective phases.

Abstract: This invention relates to cab signalling systems that receive various permissible maximum speed signals and decode the maximum speed signal to inform the engineman of a train of the current maximum safe speed that a train may travel. The apparatus of this invention accomplishes the foregoing by utilizing a single digital filter and a microprocessor to decode the various transmitted maximum speed signals and to verify that the decoded maximum speed signal represents one of the permissible maximum safe speeds.