Showing papers on "Stub (electronics) published in 1990"

Electronic circuit device

Abstract: An electronic circuit device comprises a printed circuit board (3) having a first surface on which a circuit pattern (6) is formed on which components (7) are mounted and a second surface on which a ground plane (5) is formed, a coupling stub (15) being formed in part of the circuit pattern; and a plane antenna having an antenna element (1), formed on one surface of a dielectric substrate (2) The printed circuit board (3) and the plane antenna are unified such that the second surface of the printed circuit board (3) and the other surface of the dielectric substrate (2) are opposed to each other and the coupling stub (15) is placed in position to be coupled to the antenna element (1)

Intramedullary pin with self-locking end for metadiaphyseal fractures of long bones

Abstract: Intramedullary pin (1) with self-locking end for metadiaphyseal fractures, constituted by a proximal stub (2) provided with means (3) for fixing to the cortices; the ends of at least two curved and elastically deformable stems (8) are axially rigidly associated with the stub (2), and the stems (8) are adapted to expand elastically and to press with their tips (9) the walls of the bone from the inside of the medullary canal.

A multiradius, reciprocal implementation of the thin-wire moment method

Abstract: An implementation of the moment method, entitled the multiradius bridge-current (MBC) moment method, for electromagnetic analysis of multiradius thin-wire structures (including multiwire, multiradius junctions) is presented. It is extension of the authors' uniradius bridge-current reformulation (see ibid., vol.37, p.1224-34, Oct. 1989) of Richmond's uniradius thin-wire theory (1974). The method features an exactly symmetric mutual impedance matrix ensuring reciprocity between sources, it is unconstrained with respect to both the length ratio and the radius ratio of adjoining segments (provided that the wires are electrically thin), and it permits the self-consistent inclusion of coaxial cable sections in the configurations under analysis. The method is validated through comparison with transmission-line theory for a two-wire line and a coaxial cable, and through comparison with measurements on a sleeve monopole antenna and a log-periodic dipole antenna. The MBC moment method program is shown to surpass the Numerical Electromagnetics Code (NEC) in terms of reciprocity and convergence for both an AM broadcast tower detuning stub problem and a bent two-wire transmission-line problem. >

High-frequency feeding method for use in plasma apparatus and device for carrying out the method

Abstract: In a plasma apparatus, electric power is transmitted from a high-frequency power supply to an electrode in a plasma chamber through a feeding cable. A stub connected to the feeding cable as a matching component removes the capacitive component of the impedance of a plasma produced in the plasma chamber and equalizes the resistive component of the impedance of the plasma to the characteristic impedance of the feeding cable. As a result, the impedance of the plasma and the characteristic impedance of the feeding cable are matched, and the transmitting efficiency of the electric power is enhanced. A phase shift circuit may be used instead of the stub.

Lightning protection apparatus for rf equipment and the like

Abstract: Lightning protection apparatus for antenna-coupled RF equipment is provided. A one quarter wavelength shorting stub bandpass filter shunts the RF equipment and a distributed capacitance, high voltage coaxial capacitor is serially coupled between the equipment and antenna. The shorting stub is tuned to one quarter wavelength of the RF equipment operating frequency. The series capacitor passes frequencies at or above the operating frequency of the RF equipment.

Microwave frequency range electro-optic modulator with efficient input coupling and smooth wideband frequency response

Abstract: A travelling-wave Mach-Zehnder electro-optic modulator (10) for operation at microwave electrical input signal frequencies has an electrical modulation electrode structure (26,34) which constitutes a coplanar waveguide (24). An electrical input signal connector (80) is coupled to a microstrip line (38) having an output impedance which is significantly different from the input impedance of the waveguide (24). A Chebyshev impedance matching transformer (50) couples the input signal from the input connector (80) to the modulation electrode structure (26,34), while matching the output impedance of the microstrip line (38) to the input impedance of the waveguide (24) to maximize the coupling efficiency and minimize return loss. The modulato GOVERNMENT RIGHTS This invention was made with Government support under Contract No. N66604-87-C-1126 awarded by the Department of the Navy. The Government has certain rights in this invention.

Millimeter wave microstrip shunt-mounted pin diode switch with particular bias means

Abstract: A millimeter wave microstrip shunt-mounted PIN diode switch having its DC ground separate from RF ground is created by utilizing a fan structure (radial stub) having a radius of approximately one-quarter wavelength to provide an RF ground at that location and then coupling the DC bias supplies to that RF ground location. By doing so and by proper attention to known design practices for laying out microstrip circuitry, the need for blocking capacitors required by prior art arrangements is eliminated.

Reduction of parasitic coupling in packaged MMICs

Abstract: Electromagnetic coupling between circuit elements within a package is often significant, or even catastrophic, at frequencies near a package resonance. In future, large, highly integrated, millimeter-wave MMICs, this resonant coupling will be difficult to avoid. The addition of lossy materials to the enclosure will reduce the coupling, but not eliminate it. A rigorous application of the method of moments is used to determine the relative amount of power coupled from a microstrip circuit in an enclosure to a resonant mode. The full-wave analysis is used to analyze a large gap in a transmission line and a transmission line with a single shunt open-circuit stub attached midway between the input and output connectors. The scattering parameters and the power lost to the resonant modes of the enclosure are determined. The results indicate that a further reduction in the coupling of power to the resonant modes is possible by repositioning the circuit within the enclosure. >

Method of manufacturing a rotor assembly

Abstract: A compressor rotor structure for a gas turbine engine is made by linear friction bonding stub rooted blades and separate platform pieces, to lands between slots in a compressor disc periphery These results an integral structure in which the periphery of the disc has had metal removed so as to form the slots and the disc is thus lightened, and the stub roots and platform pieces cooperate to form the airflow inner annulus wall

Intake air filter for an internal combustion engine

Abstract: A filter device, especially an intake air filter for internal combustion engines, comprises a cylindrical filter housing (1) with inlet and outlet openings (7, 6) for the medium. In the outlet opening (6), a pipe stub (11) is fixed with the aid of an elastic sleeve (12), which forms a seal between the opening edge (14) and the stub and between the stub and an intake conduit (15) coupled thereto. The pipe stub has a portion (11a) extending into the filter housing, against which portion (11a) there seals a radial seal (17) on a filter element (2) enclosed in the housing.

Quantum susceptance and its effects on the high-frequency response of superconducting tunnel junctions.

Abstract: We have made the first direct measurement of the quantum susceptance that arises from the nondissipative part of quasiparticle tunneling in a superconductor-insulator-superconductor tunnel junction. The junction is coupled to an antenna and a superconducting microstrip stub to form a resonator; the resonant frequency is determined from the response of the junction to broadband radiation from a Fourier-transform spectrometer. A 19% shift of the resonant frequency, from 73 to 87 GHz, is observed, which arises from the change of the quantum susceptance of the junction with dc bias voltage. This shift is in excellent agreement with calculations based on the Werthamer-Tucker theory, which includes the quantum susceptance. We also demonstrate that it is essential to include the quantum susceptance in our theoretical computation to explain the photon-assisted-tunneling steps, which have negative dynamic conductance. Such steps are observed when the junction is pumped at slightly below the resonant frequency of the capacitor and the stub. The quantum susceptance should exist in all tunnel devices whose nonlinear {ital I}-{ital V} characteristics are due to elastic tunneling.

Statistical design techniques for high-speed circuit boards with correlated structure distributions

Abstract: New statistical techniques have been developed for designing the line structures of high-speed circuit boards. These techniques take into account the correlations between dimensional deviations caused by the fabrication process. Monte Carlo simulation is introduced into the finite-element method in order to calculate distributions of line parameters, and distributed circuit models are used to calculate the corresponding eye-patterns at the receiving end of transmission lines with parallel and stub parts. The simulator has an algorithm to save computer time. This paper compares the calculated and experimental results and discusses the accuracy of the simulation. Calculation results imply that the evaluation of the dimensional distributions due to fabrication processes is very important. The timing and amplitude margins, for example, were found to strongly depend on fabrication deviations. These techniques may be easily applied to the control of fabrication deviations to ensure that high-speed circuit boards meet electrical requirements. >

Variable bi-phase modulator circuits and variable resistors for microwave signals

Abstract: A variable bi-phase modulator circuit for microwave signals includes a quadrature power divider (1) having signal input and output ports (2 and 3) and two control ports (4 and 5), and two variable resistors each having an input port (11). Each of the two variable resistors includes first and second microwave field-effect transistors (F1 and F2), the drains of which are coupled together via an intermediate resistor (R). These resistors can be formed using microwave monolithic integrated circuit technology and can have very good impedance characteristics. The input port (11) of the variable resistor has a connection to the intermediate resistor (R) and to the drain of the first transistor (F2). Each transistor is connected with zero dc bias between its source and drain and has a channel resistance which changes with change in gate voltage (VG1, VG2). A shunt stub (L1, L2) is connected to the drain of each transistor (F1, F2) to at least partially compensate at the frequency of operation of the transistor for the source to drain capacitance and for shifts in reference plane due to changes in the gate voltage of each transistor.

Electronically tuned VHF/UHF matching network

Abstract: A matching network matches an output impedance of a source with an input impedance of a load. The matching network includes a plurality of transmission line stubs. Each transmission line stub includes a first transmission line conductor, a second transmission line conductor running parallel to but not in electrical contact with the first transmission line conductor, and ferrite dielectric material between the first transmission line conductor and the second transmission line conductor. A magnetic field is used to vary the relative permeability of the ferrite dielectric material.

Tem coaxial resonator

Abstract: A coaxial resonance cavity of either the fingered or unfingered variety having a metal heat conducting barbell shaped structure (21) inside the movable tuning plunger (9) to conduct heat from the inner surface of the movable plunger to the inner surface of a fixed stub (20) or directly to a shield (1) to provide for a heat conductive path to the shield to carry heat away from the inner plunger. The barbell is an integral structure machined from stock aluminum, but resembles three right circular cylinders (22,23,24) butting end to circular end. The upper cylinder (22) has a diameter appropriate to maintain tight contact with the stub. The lower cylinder (23) has a smaller diameter, appropriate to maintain contact with the movable plunger. The central cylinder (24) has a diameter which is sufficiently small to avoid contact with any portion of friction buttons (26) located on the side of the plunger to serve as a spacer between the plunger and the stub, especially such portion (27) of the button which may extend entirely through the plunger for support of the button.

Automatic textile winder - has a transport system with independent pallets for the cops which are secured by an elastic element on the stub spindle

Abstract: An automatic winder has a transport system for cops. The cops are carried on pallets having a base disc and projecting steps to a stub spindle. The stub spindle is equipped with an elastic element to grip the interior of the cop tube. The base plate (2) consists of an outer ring with spokes joining a central boss (3). The projection (4) serves as a support for the base of the tube on which the cop is wound. The stub spindle has a cone top (6) to ease into the bore of the cop tube. Reduction in diameter for the appropriate length, enables a balloon spring to be fitted around the stub spindle. When expanded, this has a larger diameter than the interior of the tube, and when this is pressed on, there is an even spring grip. Instead of the balloon spring, two radial grooves are cut in the shank of the stub spindle. Two rubber rings are then pressed over the spindle, and lie into the grooves. The exterior diameter is larger than the bore of the tube, to make a tight fit when the cop is pressed down. Devices are also claimed which enable the cop to be pressed on to the pallet spindle. ADVANTAGE - The cop sits on the pallet firmly. This eliminates the necessity to provide other devices to align the cops in the machinery. The fittings are economical, even when numerous pallets are in use.

Filter device, particularly intake air filter device for combustion engines

Abstract: A filter device, especially an intake air filter for internal combustion engines, comprises a cylindrical filter housing (1) with inlet and outlet openings (7, 6) for the medium. In the outlet opening, the pipe stub (11) is fixed with the aid of an elastic sleeve (12). The pipe stub is solidly joined to a secondary or safety filter (20) which extends within a main filter (2), which has a radial seal (17) which seals against a portion (11a) of the pipe stub extending into the housing.

Castellated valve wrench

Abstract: An apparatus for engaging and rotating large and/or difficult to turn handwheels of valves includes a castellated drive member and separable ratchet drive assembly. The drive member includes a plurality of T-shaped slots which receive and retain the spokes of a valve wheel. The drive member also includes a multi-sided stub defining a through, axial passageway. The stub is removably received within a complementarily configured passageway in a collar of the ratchet drive assembly. The collar, in turn, is received within a housing and is acted upon by a pawl. An elongate handle extends radially from the housing and facilitates the application of significant torque to the apparatus and an associated valve handwheel.

Clamp for fastening of a post element

Abstract: For fastening of a post element, such as a lamp post to a post stub, for instance a stub remaining after a damaged lamp post, it is designed a clamp consisting of a tubular section (1) which interacts with and is fixed to the remaining post stub, and with a mounting plate for the new post. The tubular section has a diameter which is adapted for insertion in the post stub. At the inside of the section (1), in the area below the mounting plate (2) it is provided fastening screws (9) which are acting against the post stub. Below the screws it is provided a crossing bridge piece with a center hole. The tubular section (1) is at its free end provided with slots (3). Through the bridge piece it is arranged a screw (4) at one end of which it is provided a body (5) with a wedge formed outer circumference (6). By tightening of a nut (12) the wedge formed body (5) will be pulled into the slotted part of the sleeve and will press it out for firm wedging against the tubular section (1). As an alternative the tubular section (1) may have at least one conical part and its largest diameter may be adapted for insertion in the post stub.

Method and apparatus for plasma treatment

Abstract: PURPOSE: To obtain a technique which can enhance the stability of a plasma discharge operation and the reproducibility of a process by a method wherein the standing-wave amount generated with reference to given microwaves is detected, the impedance value of a load is computed and the impedance on the side of a microwave generation source is matched to the impedance on the side of a plasma production chamber on the basis of its computed value CONSTITUTION: When a plasma treatment is started or while the plasma treatment is being executed, the standing-wave amount generated with reference to given microwaves is detected; the impedance value of a load is computed on the basis of its detected signal; the impedance on the side of a microwave generation source 3 is matched to the impedance on the side of a plasma production chamber 9 on the basis of its computed value; and plasma-mode selection means 8 or 11a, 11b are controlled in such a way that said computed value is approached to a target value which is set in advance Thereby, a prescribed plasma stabilization mode is selected automatically out of respective plasma stabilization modes of several impedance matching points For example, electromagnetic coils 11a, 11b or a stub matching device 8 are used as said plasma- mode selection means COPYRIGHT: (C)1991,JPO&Japio

Filter device, particularly intake air filter device for combustion engines

Abstract: A filter device, particularly an intake filter for an internal combustion engine, comprises a cylindrical filter housing (1) with an inlet (7) and an outlet (6) for the medium. The housing encloses a replaceable, tubular filter element (2) at one end of which an outlet stub (11) is fixed. The stub protrudes through the outlet (6) in the housing.

Effect of idealized asymmetric inhibitor stubs on circumferential flow in the Space Shuttle SRM

Abstract: Computational fluid dynamic analyses have been performed to calculate circumferential pressure and velocity gradients in the vicinity of an asymmetric inhibitor stub in the port of the Space Shuttle solid rocket motor. The three-dimensional Navier-Stokes equations were solved by an iterative finite volume algorithm, SIMPLE, incorporated in a general purpose computer code, FLUENT. Turbulence was represented by way of effective viscosity, which was calculated from local turbulence energy and its dissipation rate (K-e model). The numerical predictions were compared with the measurements from a 1.5% scale, cold-flow model of the redesigned solid rocket motor. The calculated circumferential pressure distribution upstream of the inhibitor stub compares well with the measured data.

Drive mechanism for windscreen wiper - has sleeve over wiper stub with locating lip for seal

Abstract: The wiper stub (14) is located in its housing (13) by a sleeve bearing (16) inserted from the front and sealed via a sealing ring (18) in a space between the end of the bearing and an insert lip (28) which is part of a sleeve (25) fitted over the stub. The sleeve has an outwards directed lip (27) for additional sealing. The sealing sleeve is made from sintered metal and forms a protective covering for the stub. The stub housing is part of a redn. gearing housing which is itself part of the motor casting. USE/ADVANTAGE - Vehicle windscreen wiper drive with improved seal, less wear, longer life.

Service box, especially a flush-mounted box

Abstract: The plastic flush-mounted box (1) for electrical switches, plug sockets, cable connectors or the like is provided with at least one male connecting stub (6) and one female connecting stub (7) in order to connect a number of them together, which connecting stubs are arranged diametrically opposite and projecting radially from the circumference of the box wall. One connecting stub (7) is provided with a locking tab or a locking pawl (13, 14) and the other connecting stub (6), as the mating piece for it, is provided with a locking shoulder (38). The two connecting stubs (6, 7) are essentially cylindrical. In the half of its wall close to the base in a symmetrical arrangement with respect to the common plane of symmetry (10), one connecting stub (7) has two locking tongues (13, 14) arranged in wall apertures (10, 11), and the other connecting stub (6), as mating elements for them, has two radial locking tabs (23, 24). When coupled together, the locking tabs (23, 24) project into the wall apertures (23, 24) of the two locking tongues (13, 14) of the coupled connecting stub (7) of a second service box (1). That connecting stub (7) which is provided with the locking tongues (13, 14) and the wall apertures (11, 12) has two groove-like recesses or expansions (19, 20) in the region of the locking tongues (13, 14) as a twisting protection device, in order to accommodate the two locking tabs (23, 24) of the other connecting stub (6) of a further service box (1).

Multipiece eccentric shaft

Abstract: A crankshaft having a main bearing portion, formed by metal forging, casting or powdered metallurgy, and having coupled thereto a rotor stub portion comprising a steel tube fixedly secured to the main bearing portion, such as by press fitting, friction or laser welding. The rotor stub portion of the crankshaft is formed with suitable oil hole passages to deliver oil through the rotor stub portion to any desired location along this portion of the crankshaft.

Microwave coaxial resonator tuner - has deformable spindle nut subjected to radial compression by tightening of hexagonal nut around spindle of stub protruding into cavity

Abstract: Coaxial transmission lines are coupled (3,4) into a cavity (1) tuned by means of a stub (8) on a threaded spindle (9) passing through a nut (10) of triangular pattern tapering in the direction of the shaft (6). - The sides of the triangle are matched to the taper (12) of the shaft (6) so that axial pressure from a hexagonal nut (13) is converted into radial force on the triangular one (10). The latter may have a dia. of 7.7. mm and min. wall thickness 0.5 mm.

Apparatus for replacing defective electronic components

Abstract: A method of replacing a defective electronic component having a plurality of electrical leads bonded to electrical contacts on a support by cutting leads adjacent the bond site, rebonding the stubs to the contacts, replacing the defective component and bonding the leads of the replacement component to the electrical contacts. Preferably, the leads are cut simultaneously with the rebonding of the stubs. The leads may be bonded to the top of the stub or to the side of the stub. A bonding tool is provided for simultaneously cutting a lead and rebonding the resultant stub.

Impedance matched coaxial transmission system

Abstract: A coaxial transmission line system includes a coaxial transmission line having a center conductor and an outer conductor, and an rf generator. A stub antenna is coupled to the generator, and extends radially into the transmission line between the outer and center conductors for capacitively coupling rf energy from the generator to the center conductor. Input impedance of the coaxial transmission line is matched to the impedance of the antenna and generator by means of a pair of tuning screws that extend radially into the transmission line between the outer and center conductors adjacent to the antenna. The tuning screws are adjustably positionable radially of the center conductor and are spaced from each other lengthwise of the transmission line.

Fuel identification for filler stub - has marked discs clamped over filler stub and under filler cap

Abstract: The identification discs are made from plastic, card, fibre etc. and are marked with the fuel information. They are placed over the filler stub and clearly indicate to the user which fuel to use e.g. lead free, diesel etc. The discs can be supplied with advertising logos as give-aways, and are coloured for simple recognition. The central hole ensures a secure fit around the filler stub. ADVANTAGE - Simple indication of fuel type, allows special fuel programs e.g. filling with leaded fuel every set number of normal fillings.