Showing papers on "Stub (electronics) published in 1989"

Theory for a quantum modulated transistor

Abstract: We present a theoretical study of semiconductor T‐structures which may exhibit transistor action based on quantum interference. The electron transmission through a semiconductor quantum wire can be controlled by an external gate voltage that modifies the penetration of the electron wavefunction in a lateral stub, affecting in this way its interference pattern. The structures are modeled as ideal two‐dimensional electron waveguides and a tight‐binding Green’s function technique is used to compute the electron transmission and reflection coefficients. The calculations show that relatively small changes in the stub length can induce strong variations in the electron transmission across the structure. Operation in the fundamental transverse mode appears to be important for applications. We also show that a bound state of purely geometrical origin nucleates at the intersection between waveguide and stub. The performance of the device can be improved by inserting additional stubs of slightly different lengths. ...

Full-wave, finite element analysis of irregular microstrip discontinuities

Abstract: Finite-element expansion currents are used to formulate a full-wave analysis of microstrip discontinuities With this approach, a rigorous analysis of fairly irregular structures is possible, including radiation and surface wave effects as well as coupling between closely spaced junctions The step, stub, and bent-stub discontinuities are analyzed using this technique Measurements are made of three stub structures Measured resonant frequencies agree with full-wave calculations to within 2% when the nominal measured dielectric constant and structure dimensions are used as input Using the absolute worst case dielectric constants and dimensions as input gives an error of 3% for the low-frequency stub and less than that for the other stubs >

Fiber optic connector element and method for its use

Abstract: An optical fiber connector element comprises: a connector body having a passage extending therethrough, the passage having a forward portion for receiving an optical fiber and a rearward portion which is wider than the forward portion for receiving an optical fiber and surrounding protective material; and an optical fiber stub secured within the forward portion of the passage, the optical fiber stub having a forward end surface which has an optical finish. The connector element is used to terminate an optical fiber cable by: cutting the cable to a desired length; stripping back an end portion of protective material surrounding an optical fiber of the cable to expose an end portion of the optical fiber; and securing the exposed fiber end portion and an end portion of the protective material remaining on the fiber in the connector body passage with the fiber end portion in abutment and axial alignment with the fiber stub. The steps of securing the fiber stub within the connector body passage, trimming the forward end portion of the fiber stub and polishing the forward end surface of the fiber stub may be performed under controlled factory conditions and the steps of cutting the cable to the desired length, stripping back the end portion of protective material, and securing the fiber end portion within the connector body passage may be performed under field conditions. The optical fiber connector element and its method of use avoid the need for polishing a fiber end to an optical finish under adverse field conditions.

Fabrication or repair technique for integrally bladed rotor assembly

Abstract: Techniques for fabricating or repairing integrally bladed rotors are developed. A new or replacement blade is bonded to a projecting stub. The new blade has a collar through which bonding forces are transmitted. After bonding with heat and pressure, final machining and heat treatment operations are performed.

Multi-frequency band phased array antenna using coplanar dipole array with multiple feed ports

Abstract: In a printed circuit embodiment, dielectric boards in a multilayer arrangement have their ends protruding from a ground plane. Sets of printed dipole elements are disposed along the edge of each board. Each set of dipole elements has three feed ports. Bandpass filters are provided for each feed port. Phase shifters are coupled to each of the feed ports through its respective bandpass filter. At the low band, the outer feed ports are shorted by the filters so that the two sections of dipole elements to the left of the center feed port form one lone band dipole arm, and the two sections of dipole elements to the right of the center feed port form the other low band dipole arm. The low band dipole is driven at the center feed port. At the high band, the center feed port becomes an open circuit so that the two sections to the left thereof form one high band dipole, and the two sections to the right thereof form a second high band dipole. The two outer feed ports drive the dipole array at the high band. In an MMIC embodiment, printed circuit stubs are bridged across the outer feed ports. The length of each stub is one wavelength at the low frequency band, and one-and-one-half wavelengths at the high frequency band. At the low frequency, the stubs appear to be short-circuited. At the high frequency band, the terminals of the stubs provide a 180 degree phase difference for a balun.

Apparatus for bonding an article projection

Abstract: A method for reparing or manufacturing an article, such as a bladed disk, having an integral projection, for example an airfoil, includes first removing a damaged projection to provide a stub, or in new manufacture providing the stub. A collar shaped to register with the stub is provided and bonded to the stub to generate a stub-collar combination. Then a replacement or new projection member is bonded to the stub-collar combination. Finishing then provides the article. Apparatus includes the combination of a metal attachment die and a heating means retained in a recess of the die during bonding.

Combined mine probe and marker

Abstract: A combined probe and marker for probing mines as well as marking mines oncehey have been discovered, and marking a path free of mines, comprises a rod rigidly connected to a handle. At the upper end of the handle, there is a recess for frictionally holding a Combat Light Device. In another version of this invention, the handle has a central bore followed by a concentric threaded bore at the lower end of the handle. The rod is affixed to one of the threaded ends of a stub which has a middle enlarged section for removably attaching and storing the rod.

Glass-treating furnace with roller conveyor

Abstract: A furnace for the heat treating of glass, has a housing defining an elongated furnace chamber having opposite longitudinal sides and having an inlet end and an outlet end. A roller conveyor extends between the inlet end and the outlet end. The roller conveyor has a respective row of stub rollers spaced apart along each longitudinal side of the chamber, and respective conveyor rollers spanning the rows of stub rollers and cradled thereby. A respective idler pulley is disposed between each two successive stub rollers along one of the longitudinal sides of the chamber, the idler pulleys lying in a further row below the row of stub rollers. An endless drive element overshoots two successive stub rollers of the section in a respective single loop and undershoots each of the pulleys in a respective single loop between each of the two successive stub rollers to reduce the required driving power.

MM wave quasioptical SIS mixers

Abstract: The authors have tested the performance of planar SIS (superconductor-insulator-superconductor) mixers with log-periodic antennas at near millimeter and submillimeter wave frequencies from 90 to 360 GHz. The large omega R/sub N/C product ( approximately 10 at 90 GHz) of the Nb/NbO/sub x//Pb-In-Au junctions requires an integrated inductive tuning element to resonate the junction capacitance at the operating frequencies. Two types of integrated tuning element were used which were designed with the aid of measurements using a Fourier transform spectrometer. Preliminary results indicate that the tuning elements can give very good mixer performance up to at least 200 GHz. An inductive wire in parallel with a 5-junction array gives a minimum mixer noise temperature of 115 K (DSB) at 90 GHz with a FWHM (full width at half maximum) bandwidth of 8 GHz. An open-ended microstrip stub in parallel with a single junction gives minimum mixer noise temperatures at 150 and 200 K (DSB) near 90 and 180 GHz with FWHM bandwidths of 4 and 3 GHz, respectively. The relatively high mixer noise temperatures compared to those of waveguide SIS mixers in a similar frequency range are attributed mainly to the losses in the optical system. >

Container with cap-type closure

Abstract: A cap-type container has a tube stub formed directly from sheet metal of the container cover and from which the opening can be shaped. The tube stub is externally threaded and cooperates with a cap provided with a sealing ring engaging an annular surface of the tube stub. The latter can be double walled and a reinforcing ring inserted between the walls.

Conveyor stub idler apparatus

Abstract: Stub idler units for a flexible sidewall belt conveyors support the return belt run Each unit includes a stub roll fixed to and forming an integral part of a solid shaft A pair of re-lubricable, sealed bearings are mounted within opposite ends of a tubular bearing housing secured within a tubular mounting bracket The shaft is journaled in the bearings clamped to the housing by a locking nut on the shaft end A lubrication passageway is formed in the mounting bracket and housing and provided with a lubrication fitting The passageway connects to the chamber between the bearings lubricating the bearings A flexible hydraulic grease line is attached to the far side mounting bracket in place of the grease fitting The grease line extends across the conveyor belt to the near side of the conveyor and terminates in a grease fitting for re-lubrication of the far side stub idler The line is supported at the two mounting brackets by suitable shaped support elements mounted to the mounting brackets

Device for indicating a measurement result

Abstract: In a device for indicating a measurement result of a quantity to be measured, with a housing (1) accommodating an indicating device (12) and with a connecting stub (7), it is provided, for the purpose of facilitating the adaptation to different installation or assembly requirements, that the housing (1) exhibits at least two housing parts (2, 3), the connecting stub (7) and indicating device (12) are arranged at different housing parts (2 or 3), and that the housing parts (2, 3) exhibit a cross-section in the form of an octagon in a top view of the indicating device (12) and the housing parts (2, 3) can be joined together and connected to one another to form an essentially closed housing (1) after a rotation by an angle of in each case 45@ with respect to one another.

Strap shortening device

Abstract: A device for use in reducing the effective length of an endless strap, such as on a pocketbook, consists of a body having a number of pairs of aligned stub elements along opposite sides of a cavity defined therewithin. The strap is inserted through slots formed in end portions of the body, to lie within channels extending therethrough, and is threaded about and affixed upon the crosspiece structures provided.

Method and device for directing and controlling the operation of an injection molding machine

Abstract: A method and device for directing and controlling the operation of an injection molding machine having sensors which provide actual values during machine operation, the machine having actuators forming and executing control orders received from the sensors. The sensors and actuators are serially connected via a closed loop control cable such that all information is available in successive words. The sensors and/or actuators deliver their information jointly and in dependence on the status of the program. The actuators jointly execute their control orders in corresponding numbers. The actuators and sensors are coupled through interface couplers to the closed loop or stub cable.

E-polarization diffraction by a thick metal-dielectric join

Abstract: A solution of the diffraction from a dielectric-metallic join due to an incident E1 -polarized plane wave is presented. Direct diffraction, coupling, launching, and reflection subproblems associated with a loaded parallel-plate waveguide are first treated via the dual integral equation method. The results are subsequently combined in the context of the generalized scattering matrix formulation to obtain the diffraction from the truncated parallel-plate waveguide with a recessed stub and a dielectric loading extending to infinity. The stub is then restored to the waveguide mouth to obtain the diffraction by the dielectric-metallic join. As expected, the final expressions involve several Wiener-Hopf split functions and an efficient numerical technique for their evaluation is given in an appendix. The convergence of the solution with respect to the number of included modes is examined and a number of scattering patterns are presented.

Microwave circuit, bias circuit, and band stop filter

Abstract: PURPOSE: To obtain a small-sized microwave circuit where the loss due to radiation is small by providing a strip line in parallel with a micro strip line and multilayering a terminal open line by the strip line and connecting its one end and the micro strip line by a through hole. CONSTITUTION: A terminal open stub 280 functions as the reactance element which has both ends connected between a micro strip line 230 and the ground. Since the terminal open stub 280 and the micro strip line 230 are separated by a ground conductor 220 and are not coupled to each other, the terminal open stub 280 can be provided in parallel with the micro strip line 230. The terminal open stub 280 consisting of the strip line is interposed between ground conductors 220 and 225. Thus, the small-sized microwave circuit is obtained where the loss due to radiation in the pass band is small. COPYRIGHT: (C)1991,JPO&Japio

Apparatus for rotatably mounting idlers and pulleys of various sizes

Abstract: An apparatus for rotatably mounting idlers and pulleys of various sizes, including an idler or pulley for engaging the underside of a conveyor belt. The idler or pulley includes a cylindrical chamber in each end for reception of bearing assemblies therein. Each of the bearing assemblies in each end of the idler or pulley has a stub shaft therein. An elongated member which is tubular, at least at each end thereof, is press fit onto the inner ends of each of the stub shafts whereby the length of the elongated member can be chosen depending upon the length of the idler or pulley, while at the same time identical standard bearing assemblies and stub shafts can be used for idler pulleys of various sizes.

Method 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.

Scattering from a stub loaded microstrip antenna

Abstract: Theoretical and experimental results are reported and compared for a stub loaded microstrip element. Investigation into the scattering characteristics of this element was motivated by the desire to use this element in a reflect array. In this application an incident field from a primary feed is scattered by an array of stub loaded microstrip elements. By proper stub design, the phase of the scattered field from each array element may be controlled such that a collimated secondary radiation pattern is formed. Emphasis is placed on determining the relationship between the phase and amplitude of the scattered field as a function of stub length. >

High power microwave line with arbitrary impedance matching capability for plasma applications

Abstract: The details of a high power microwave transmission line developed for plasma applications are presented. The line operates at 2.45 GHz and can handle about ≲1 kW of cw microwave power with about 15%–20% insertion loss. A special feature of the line is its wide range impedance matching capability for operating under different load conditions. A coaxial triple stub tuner capable of handling high power cw microwaves was especially developed for this purpose. Detailed design considerations for the tuner and other critical components like the high power vacuum seal are presented.

System for releasably coupling a stub shaft extending from a printing cylinder to a shaft passing through a machine side wall

Abstract: To permit radial removal of a cylinder, roller or similar element in a printing machine from between the side walls (1) thereof, the cylinder or roller (9) is formed with two stub shafts (8) coupled by separable half-shells (5, 6) to the ends of shaft elements (3) passing through the side wall (1) of the printing machine One of said shaft elements can be coupled to a drive gear (4) In accordance with the invention, and to permit rolling off of the stub shaft (8) of the cylinder over the half-shell, the separating surfaces (10, 11, 12, 13) between the half-shells are formed to extend essentially tangentially with respect to the part-circular clamping surfaces (14, 15) which clamp the stub shaft to the shafts (3) passing through the side wall, one of the half-shells being secured to the shaft elements Preferably, a locating abutment or notch (17) is formed on the half-shell (6) secured to the machine shaft (3) to permit placement of a locating projection (18) on a roll-out rail (19) against the half shell so that, upon removal of the other half-shell (7), the cylinder can be rolled off on the rail after passing over the separating surface

Stub detuners for free-standing towers

Abstract: A standard broadcast AM radio station's antenna pattern has minima in the directions of other cities with stations on the same frequency. However, scattering can raise the field strength in a certain direction to unacceptably high levels. The scatterer must then be identified and modified or detuned so that it no longer scatters the field. Several detuner designs are presented for installation on a powerline tower for the suppression of the scattered field. The emphasis is on the assessment of the bandwidth over which scattering is suppressed, and on how the detuner can be modified to increase the bandwidth . The performance of detuners is studied by computing the scattered field from a type V1S power line tower using the Numerical Electromagnetics Code. The uses of a detuning skirt or detuning stub are also investigated. It is shown that the bandwidth can be improved by increasing the stub length, as in the elbow stub design. It is further shown that a large increase in bandwidth can be achieved by separating the stub significantly from the tower, thus increasing the energy loss in the resonant system. The effectiveness of the proposed stub designs is investigated by the measurement of the base impedance of the scale model tower detuned with each stub design. The measured impedances bear out the conclusions that the bandwidth of a capacitively tuned stub is improved by increasing the stub length, that the bandwidth of a stub can be increased by separating the stub wire from the tower body, and that the wire stub designs offer as good or better performance than do the capacitively tuned stub designs. >

Stub axle truck

Abstract: A truck having a pair of wheels mounted by individual stub axles to longitudinal members of a frame. Lateral members of the frame received the forces from the wheels via the longitudinal members and forces from the car via air springs mouted to the lateral members adjacent the longitudinal members. The stub axles are easily removed from U-shaped retainers. A sleeve through the hollow axle retains the bearings to the axle. Half shafts interconnects/a gear box and the stub axles for driven trucks and the interconnect are dimensioned to allow the shafts to be removed axially through the hollow axle.

Second-harmonic-wave chocking filter

Abstract: A strip-type second-harmonic-choking filter is constituted such that a main transmission line, through which a fundamental frequency wave is to be transmitted, is connected with first and second stub. The first stub exhibits a first susceptance value for the fundamental frequency and exhibits a subtantially infinite admittance value for a second harmonic of the fundamental frequency, on one side of said main transmission line. A second stub exhibits a second susceptance value which is essentially a conjugate of the first susceptance value for the fundamental frequency and exhibits an infinity or zero admittance value for the second harmonic frequency, at an opposite side of the transmission line from the first stub. For the fundamental frequency wave, the two stubs cancel the effects of each other so that no effect is given on the transmission of the fundamental wave, while one or both of the stubs choke the transmission of the second-harmonic wave. The stub may be bent so that more area is easily available for circuits to be installed on the same circuit board.

Multipurpose furniture/equipment.

Abstract: Multipurpose furniture/equipment, wherein a seat frame (1) is provided with stub legs (5) pivotable between stowed or user positions and adapted interchangeably to receive differing constructions of leg assemblies (14,15) and attachments (9) therefore, the arrangement being such as to enable establishment of differing user functions for the furniture/equipment. The leg assemblies are selectively lengthwise adjustable thereby to enable selective adjustment of user height of the seat frame. In addition wheel assemblies (34) are adapted for connection to the stub legs or leg arrangemnts whereby the furniture/equipment can be wheeled from place to place.

Self lubricating bearing

Abstract: The present invention is a self-lubricating bearing for a vertical shaft engine. A stub (34,50) disposed within the journal bearing (30,52,74) has a downwardly facing pocket (44,60) which propels oil upward by centrifugal force during rotation of the shaft (12,72,90). The upwardly forced oil serves to lubricate the bearing (30,52,74) above the stub (34,50). The lubrication system can be employed in both stub shaft (32) and through shaft (70,94) journal bearings.

Drop-in isolator

Abstract: PURPOSE:To prevent the characteristic deterioration of a fundamental wave by providing a higher harmonic termination formed by a termination resistance and a stub at a conductor input part of a magnetic material substrate supported through a spacer onto a magnet and constituting the open stub or short stub of a necessary wavelength. CONSTITUTION:A magnetic material substrate 1 is supported through a spacer 6 onto a magnet 7, a thick film conductor 2 of the pattern of a circle, etc., is printed on the surface of the substrate 1 and a drop-in isolator is formed. A termination resistance 4 and a stub 5 are connected to an input part 2a of the conductor 2, and the stub 5 constitutes either of the open stub of a 1/4 wavelength or the short stub of a 1/2 wavelength for the higher harmonic of twice as much as the fundamental wave. Thus, the reflection of the higher harmonic is prevented and the characteristic deterioration of the fundamental wave can be prevented.

H-polarization diffraction by a thick metal-dielectric join

Abstract: An analysis is presented of the H-polarization diffraction due to a material discontinuity formed by the junction of a thick dielectric half-plane with a metallic half-plane having the same thickness. This is accomplished by first considering the solution of several subproblems. These include the direct diffraction and coupling due to a plane wave incident on a loaded open-ended parallel plate waveguide and radiation and reflection by a waveguide mode. The final solution for diffraction by the metal-dielectric join is obtained by introducing a perfectly conducting stub within the loaded guide and subsequently using the generalized scattering matrix formulation with the stub brought to the waveguide opening. All the analysis relating to the subproblems is done by the dual integral equation approach. As expected, the final expressions involve several Wiener-Hopf split functions which are evaluated numerically or analytically. >

Device for heating a flowing medium, in particular water

Abstract: A device for heating a flowing medium, in particular water, has a housing (3) into which the water is introduced through a connecting stub (4). Flow channels which are formed by the longitudinal grooves (10) of a carrier element (2) inserted into the housing (3) are located in the housing (3). In each of these flow channels a heating element is arranged in the shape of a platelet (1) which is formed in each case by at least one chip for heating the water. This results in a compact economically working construction (Fig. 1).

Torque transmitting device.

Abstract: To enable a torque transmitting device to be mounted between and removed from spaced aligned stub shafts (2a, 3a) (eg of an electric motor (2) and a pump (3) without moving the stub shafts, the device is divisible and comprises three rotary members (15, 20, 30) connected serially with an elastic coupling (13B) and a controllable variable-slip clutch (10C) (eg a multi-disc visco-hydraulic clutch) and a stationary member (40) able to transmit control signals to the cloth At least three of the four members (15, 20, 30, 40) have central openings allowing insertion of the stub shafts