Abstract: A pumping system is provided in which a low pressure metering pump injects fluid charges into a high pressure pump which in turn operates into a high pressure load. The high pressure pump is designed to always present a low pressure at its input on its intake stroke. This insures that the metering pump will always operate into a low pressure regardless of the load, and will therefore be enabled to always accurately meter charges into the high pressure pump.In various embodiments, the high pressure pump and/or the low pressure pump include spring elements for providing well defined pumping pressures.In some embodiments, an oil reservoir and diaphragm provide a well defined pressure against which the metering pump can operate.

Abstract: A model aircraft is constructed from a material having a plurality of parallel channels therein, e.g., corrugated cardboard. The aircraft is formed so that all of the various side, top, and bottom panels are gently curved over the length of the fuselage to provide a stressed fuselage which is aerodynamically sound, attractive, and extremely strong. A pair of wings are constructed so that each wing has span-wise corrugations along which bends or folds are made to produce an airfoil, e.g., by conforming to the shape of a number of ribs which define the airfoil shape. Dihedral of the wings is provided by a number of spring-like elements such as wires which can be bent and inserted into corrugations in the wings to join the wings at the required dihedral angle while allowing span-wise flexibility of the wings. The wings may be inserted into slots in the fuselage and rest upon a wing saddle therein. In accordance with different embodiments of the invention, alternate wing structures are provided.

Abstract: A semiconductor charge storage and detection device is provided in which an ion implanted conductive channel is buried between source and drain regions in the bulk of a semiconductor substrate. A charge storage region extends between the channel and the surface of the semiconductor device. The charge storage region is isolated from the semiconductor substrate and may be depleted of charge or enabled to store charge depending upon the electrical potential applied to a gate electrode at the surface of the device. The amount of charge stored may be detected by sensing the conductance of the buried channel. The device may be variously configured, e.g. as a non-destructive readable photosensor or as a memory cell.

Abstract: Improved recovery of information from magnetic tapes is provided by storing information on the tapes in the form of a number of partitions, each containing a certain number of words. A check-sum word is included at the end of each partition. When data words are stored on the tape, each partition may be of a fixed maximum length. When program lines are stored on the tape, each partition is preferably of a length such that an integral number of program lines is included in each partition. When information is read from the tape, a comparison of a sum formed from the digits stored in a partition with the associated check-sum word forms the basis for detecting an error read within a partition. An error message may be generated to alert a user to the error, while only a small amount of information on the tape is affected.

Abstract: A package for flat lead transistors is provided in which a raised flange provides structural rigidity to prevent damage to the flat leads of the transistor.

Abstract: A print disc and guide are configured so that the print disc can be mounted on a driving shaft transversely to the shaft axis. Removal and replacement of the print disc are thereby facilitated.

Abstract: A gas analyzer is provided which is particularly suited for making transcutaneous measurement of the CO.sub.2 concentration in the blood.In accordance with one embodiment of the invention, sample gases from the body are circulated in a cavity of the device. A rotating wheel in the cavity includes two reference cells and a sample cell which are sequentially rotated into the optical path between a source and a detector. Three signals are thereby provided which may be combined to give an output indication of the CO.sub.2 concentration in the body fluids. In a preferred embodiment, the sample cell is an "inverted cell" being in open communication with the sample gas circulating in the device so that the gas in the sample cell is a portion of the circulating gas which also surrounds the two reference cells. An output indication is thereby obtained which is insensitive to contaminants in the sample.

Abstract: A method and apparatus are provided for decoding digital information stored on magnetic tape. The "zero" and "one" bits are represented respectively on the tape by "short" and "long" distances between flux transitions. Decoding is accomplished by measuring the time between flux transitions and comparing that time with a reference time. Times longer than the reference time are decoded as "ones" while time intervals shorter than the reference time are decoded as "zeroes." To make the decoding independent of variations in tape speed the reference time is variable and in particular is made dependent on the tape speed. This is accomplished by updating the reference time based on previous "long" and "short" intervals between flux transitions. Circuitry is provided in which the various times are converted to voltages which are appropriately sampled and updated in accordance with the tape speed.

Abstract: A method is provided for etching thin film circuits or semiconductor chips to produce well defined vertically etched walls at rapid etching rates. The substrates to be etched are covered by masks and positioned on a cathode electrode enclosed in a container. Also enclosed in the container is a chemically-reactive gas used as an etchant. According to the method the cathode is negative-biased to ionize the reactive gas and attract the chemically reactive ions toward the cathode. These reactive ions impinge on the substrates in a predominantly vertical direction to produce well defined vertically etched walls.

Abstract: A logic pulser is disclosed which provides controlled pulses for stimulating a digital logic circuit under test. The pulser is serially programmed, e.g. by means of a manually operated push button switch to generate single pulses, continuous streams of pulses, or bursts of pulses.The pulser may include a visual output indicator such as an LED which flashes in a predetermined sequence to indicate in which mode the pulser is operating.The pulser may also include output circuitry which sets the voltage and automatically adjusts the width of the output pulses to provide appropriate net charge to different types of digital circuitry.

Abstract: A cartridge latching mechanism is provided in which a few simple elements function to position and latch a tape cartridge into a housing containing driving elements for the tape cartridge and magnetic heads for reading and writing on the tape. Manual insertion of the cartridge rotates the latching mechanism about a pivot point whereupon a spring force engages to create a torque which positively engages the cartridge and latches it into position. Depression of an eject button disengages the latching mechanism and rotates it in an opposite direction, whereupon the same spring generates an oppositely directed torque to positively eject the cartridge.

Abstract: The present invention provides an optical display device including a liquid crystal display integrated into a multilayer ceramic substrate assembly. The ceramic substrate may include cavities in which are embedded integrated circuits which activate the display. A three-dimensional electrical conducting network is used to interconnect the integrated circuits with a display pattern etched in a metalized layer on one surface of the ceramic substrate. Electrical connections to the display pattern are made directly from within the substrate, thereby eliminating the need to etch electrical access leads in the metallic surface. A single upper conducting plate is separated from the ceramic substrate by a window-like conducting spacer to form a cell in which a liquid crystal material may be contained. No display pattern nor electrical access leads are etched in the upper plate. Instead, the conducting spacer provides the only electrical connection to the upper plate.

Abstract: A differential detection device is provided for detecting the presence of magnetic bubbles in a data stream circulating on a magnetic wafer. The device utilizes an array of columns of permalloy elements to enlarge the magnetic bubbles being detected. A change in resistance of each of a pair of adjacent permalloy columns as a bubble traverses the detector is sensed and differentially detected to signify the presence of the bubble. In one embodiment of the invention, a second detector is used in conjunction with the first detector to provide operation in a mode in which bubbles in alternate positions in the data stream are directed into alternate channels including the first and second detectors respectively. After detection, the bubbles are redirected into a single data stream, while the output signals from the two detectors are merged to produce a data output signal reproducing the original data stream.

Abstract: A toroidal electrolyte-type angular transducer is provided for measuring angular displacement or tilt from a vertical plane. Three conducting paths in the electrolyte are established between two measuring electrodes and an auxilliary electrode respectively and a common electrode. Angular displacement is simply related to the values of the conductances in the various paths. In a preferred embodiment of the invention several guard-ring electrodes are included to divert spurious leakage currents from the common electrode so that the leakage current will not affect the measurement. The guard-ring electrodes are maintained at the same potential appearing at the collector electrode to ensure that no leakage currents pass between the two. Another preferred embodiment the invention provides that the two measuring electrodes are driven by voltages equal in magnitude and opposite in sign. A high gain operational amplifier is interconnected between the auxiliary electrode and the common electrode.

Abstract: A device is disclosed for generating a triangular wave form for use in an electronic function generator. The device employs a level detector which produces a square wave output to drive a triangular function generator in a loop arrangement.Amplitude symmetry of the triangular wave is maintained by sensing the average value and comparing it with a reference level to generate an error signal which in turn serves as a reference input to the level detector. The output of the level detector is therefore corrected to cancel drifts in the average or base line value of the triangular wave form.Time symmetry, or symmetry of the positive and negative slopes of the triangle is maintained by means of a feedback loop utilizing a stable current source. The time symmetry of the square wave is the same as that of the triangle. The square wave is sensed and serves to switch on and off the stable current source.

Abstract: A two-phase semiconductor charge transfer device is constructed using electrodes which include both a highly resistive region and a highly conductive region. An array of such electrodes is overlayed on an insulating layer which has been deposited onto a semiconductor substrate. Alternate phases of an applied two-phase voltage source are applied to alternate electrodes in the array, thereby generating an electrical potential distribution in the semiconductor. Charge, in the form of minority carriers in the semiconductor, is stored in the minima of the potential distribution. When the voltage phases are pulsed, the potential in the regions beneath the highly conductive parts of the electrodes almost instantaneously changes value. However, in the regions beneath the highly resistive parts of the electrodes, the potential changes value much more slowly. As the potential varies, charge is transferred from the region under one electrode to the region under an adjacent electrode.

Abstract: A completely enclosed housing of a magnetically permeable material contains a pair of magnetic discs. A magnetic bubble chip mounted in a gap between the magnetic discs is thereby subjected to a d.c. magnetic bias field provided by the discs but is also shielded from the effects of external magnetic fields. The device may be precisely magnetized by applying in succession two external magnetic fields of suitable magnitude, in opposite directions.