Showing papers on "Solenoid published in 2000"

Improvement in calculation of the self- and mutual inductance of thin-wall solenoids and disk coils

Abstract: The self-inductance expressions given by Yu and Han (1987) for air-core circular coils with rectangular cross sections, thin solenoids, and disk coils can be solved only by the numerical integration methods. We propose as an alternative a combined analytic and numeric approach. The approach brings some improvement in the calculations of self-inductance of thin-wall solenoids and disk coils that can be encountered in superconducting magnetic energy storage (SMES) problems. We also give a method for the calculation of mutual inductance of disk coils and of thin-wall solenoids. The results are obtained in an analytical form over the complete elliptic integrals of the first and second kind and Heuman's Lambda function. It is important to mention that the kernels of these integrals are always continuous functions on intervals of integration, so singularities are avoided. The results enable one to calculate the self-inductance and the mutual inductance of any thin air-core coil precisely and fast. For practical applications, the results are so simple to use that we recommend them to avoid the problems of solving the singular cases.

Plasma reactor having a symmetric parallel conductor coil antenna

Abstract: The invention in one embodiment is realized in a plasma reactor for processing a semiconductor workpiece. The reactor includes a vacuum chamber having a side wall and a ceiling, a workpiece support pedestal within the chamber and generally facing the ceiling, a gas inlet capable of supplying a process gas into the chamber and a solenoidal interleaved parallel conductor coil antenna overlying the ceiling and including a first plurality conductors wound about an axis of symmetry generally perpendicular to the ceiling in respective concentric helical solenoids of at least nearly uniform lateral displacements from the axis of symmetry, each helical solenoid being offset from the other helical solenoids in a direction parallel to the axis of symmetry. An RF plasma source power supply is connected across each of the plural conductors.

Extended range proportional valve

Abstract: An extended range proportional valve which can control rates of mass flow over continuous low, intermediate and high ranges has a pilot member mounted on an armature of a solenoid which can be dithered onto and off of a pilot opening in a main valve member which seals a main valve opening to control mass flow rates over the low range by varying the duty cycle and/or frequency of a pulse width modulated current in the solenoid coil. Intermediate and high flow rates are achieved by dithering the pilot valve member with a duty cycle and/or frequency sufficient to raise the main valve member relatively short and relatively long respective distances from the main valve seat.

System for control of an electromagnetic actuator

Abstract: A system for controlling the force and/or motion of an electromagnetic actuator (L1). The actuator (L1) could be a solenoid, relay, or levitating device. The drive (T1) to the coil (L1) can be linear or switching, voltage or current and the sensors (S1) measuring the system can be as simple as just a current sensor monitoring the coil current or a flux sensor. Continuous control of position can be achieved allowing magnetic levitation or the soft landing of the moving element.

Magnet system for an ECR ion source

Abstract: A superconducting magnet assembly has been built for an ECR (Electron Cyclotron Resonance) ion source at the 88-inch cyclotron at LBL. Three 34-cm ID solenoids provide axial plasma confinement and a sextupole assembly in the solenoid bore provides radial stability. Two large solenoids are spaced 50 cm. Apart with a smaller opposing solenoid between. The sextupole assembly is 92 cm long with winding inner diameter of 20 cm. And outer diameter of 27.2 cm. The design goal is to achieve a field on axis of 4 T and 3 T at the mirrors with 0.4 T between and a sextupole field of 2.0 T at 15-cm diameter in the confinement volume. Each solenoid uses rectangular conductor wish copper/SC ratio of 4; the three coils are wet-wound on a one-piece aluminum bobbin with aluminum banding for radial support. The sextupole uses rectangular conductor with copper/SC ratio of 3. Each of the 6 coils is wet-wound with filled epoxy on a metal pole; the ends of the pole are aluminum and the central 34-cm is iron to augment the sextupole field. The six coils are assembled on a 20-cm-OD stainless steel tube with a 1.4-cm thick 30.0-cm OD aluminum tube over the assembly for structural support. Thin metal bladders are expanded azimuthally between each coil and axially at tire ends to pre-load the assembly. The sextupole assembly fits inside the solenoid bobbin, which provides support for the magnetic forces. The magnet exceeds design requirements with minimum training.

Studies of electron cooling with a highly expanded electron beam

Abstract: The electron cooler at CRYRING is now operating with a superconducting gun solenoid and an electron beam that is adiabatically expanded with a factor of up to 100. This paper describes the new gun solenoid and electron gun. It presents measurements made on longitudinal cooling forces with different expansion factors, electron densities, magnetic field strengths and beam alignments. It also presents studies of a transverse beam instability that appears when a misalignment is introduced between ion and electron beams. Finally, some measurements of dielectronic recombination that directly yield transverse and longitudinal electron temperatures are discussed.

Manifold solenoid valve driven by serial signals

Abstract: In a manifold solenoid valve drive-controlled by serial signals, a solenoid valve itself is provided with a function for receiving serial signals for single valves or double valves so as to simplify assembly and replacement of the manifold solenoid valve. For this purpose, in order to transmit serial signals to solenoid valves through manifold blocks 30 on which solenoid valves 20 are mounted and which are connected, each manifold block 30 is provided with female/male connecting terminals 46a and 46b for transmitting serial signals and a connector 49 for transmitting drive control serial signals to the solenoid valves 20 and supplying drive power for switching a main valve 22. A connector 25 for transmitting and receiving power that is connected to the connector 49 when the solenoid valve 20 is mounted is provided at a position matched to the connector 49 of the manifold block. The solenoid valve 20 is provided with a slave chip 28 that extracts operation signals for solenoid valves from serial signals received through the connectors.

Progress in ATLAS central solenoid magnet

Abstract: The ATLAS central solenoid magnet is being developed to provide a magnetic field of 2 Tesla in the central tracking volume of the ATLAS detector under construction at the CERN/LHC project. The solenoid coil design features high-strength aluminum stabilized superconductor to make the coil thinnest while maintaining its stability and the pure-aluminum strip technique for quench protection and safety. The solenoid coil is installed in a common cryostat with the LAr calorimeter in order to minimize the cryostat wall. A transparency of 0.66 radiation length is achieved with these integrated efforts. The progress in the solenoid coil fabrication is reported.

Control apparatus for automatic transmission of vehicle

Abstract: In a control apparatus for that automatic transmission of a vehicle which is provided with speed-change solenoid valves for regulating the hydraulic oil pressures in the hydraulic engaging elements through speed-change control valves corresponding to the hydraulic engaging elements, cleaning work to remove foreign matter in the solenoid valves is performed by varying the opening degree of the speed-change solenoid valves during running of the vehicle without affecting the hydraulic oil pressures in the hydraulic engaging elements. At the time of a line pressure control mode in which the line pressure is reduced below a maximum set pressure, the opening degree of the speed-change solenoid valve is varied within a range in which there is outputted a signal pressure higher than a minimum signal pressure required to fully open a speed-change control valve which corresponds to the hydraulic engaging element of the then-established speed transmission train.

Dual channel cable in conduit thermohydraulics: Influence of some design parameters

Abstract: In the framework of the controlled nuclear fusion by magnetic confinement programme, a particular design of a Cable-in-Conduit Conductor (CICC) is being developed, including two parallel cooling channels. The central channel is separated from the strand channel by a spiral structure whose geometry can substantially influence the overall pressure drop. The thermo-hydraulics of this so called dual channel CICC is not well known. Hence various experiments with pressurised nitrogen at room temperature, on straight and curved unit lengths from the ITER toroidal field model coil (TFMC) production, have been performed at both Ansaldo and CEA-Cadarache to characterise the friction factor of the two parallel cooling regions, in a range of representative Reynolds numbers. These experimental results are presented. It has been possible to characterise different kinds of spiral geometries used in the manufacture of the two model coils for ITER: the TFMC and the Central Solenoid Model Coil. A relative assessment of the most suitable spiral for the ITER magnets is presented. This discussion includes: (i) manufacturing aspects with the capability of the spiral to support the cabling process as a function of the geometry of the spiral and the compaction of the cable; (ii) pressure drop considerations, as a function of the spiral geometry which plays an important role in the cooling process and the required cold pump power. Conclusions and recommendations are drawn.

Auto-calibration of a solenoid operated valve

Abstract: Operation of an electrically operated valve (20,22,34,36) is calibrated by applying a gradually increasing electric current (I c ) to the valve. While that is occurring pressure at either the inlet or outlet of the valve is measured to detect when the valve opens. When the valve opens the level of the electric current then being applied to the valve is employed to determine an initial current level (I INT ) to use subsequently whenever the valve is to be opened.

Solenoid control valve

Abstract: An engine oil solenoid control valve includes a molded one-piece valve nozzle and coil bobbin member that defines a valve nozzle and a solenoid coil bobbin and also defines an integral check valve receiving receptacle at an exhaust port and first and second valve seats for controlling valve stroke. A ball valve is disposed between the valve seats. A simple cylindrical armature rod can be used together with molded integral recesses that balance hydraulic pressure on the armature to prevent a hydraulic lock condition.

Test results for the high field conductor of the ITER central solenoid model coil

Abstract: Two Nb 3 Sn cable-in-conduit conductor sections, left over from the winding of the ITER Central Solenoid Model Coil (CSMC), have been assembled to a sample for the SULTAN facility. The test program included dc and ac performance. The quench current, I q , of the conductor is measured up to 11 T background field, 100 kA and a broad range of operating temperature. The test is repeated for different current distribution in the conductor, obtained by altering the geometry of the bottom joint. The conductor dc performance is compared to the predictions from the strand data, deduced for homogeneous and unbalanced current distribution. The ac losses under sinusoidal field sweep are measured by gas flow calorimetry. The impact of the background field and transport current on the ac losses is explored for a number of typical operating conditions. The results indicate that the coupling loss is very small.

Development of high-strength and high-RRR aluminum-stabilized superconductor for the ATLAS thin solenoid

Abstract: The ATLAS central solenoid magnet is being constructed to provide a magnetic field of 2 Tesla in the central tracking part of the ATLAS detector at the LHC. Since the solenoid coil is placed in front of the liquid-argon electromagnetic calorimeter, the solenoid coil must be as thin (and transparent) as possible. The high-strength and high-RRR aluminum-stabilized superconductor is a key technology for the solenoid to be thinnest while keeping its stability. This has been developed with an alloy of 0.1 wt% nickel addition to 5N pure aluminum and with the subsequent mechanical cold working of 21% in area reduction. A yield strength of 110 MPa at 4.2 K has been realized keeping a residual resistivity ratio (RRR) of 590, after a heat treatment corresponding to coil curing at 130/spl deg/C for 15 hrs. This paper describes the optimization of the fabrication process and characteristics of the developed conductor.

Plasma reactor having a symmetrical parallel conductor coil antenna

Abstract: The invention in one embodiment is realized in a plasma reactor for processing a semiconductor workpiece. The reactor includes a vacuum chamber having a side wall and a ceiling, a workpiece support pedestal within the chamber and generally facing the ceiling, a gas inlet capable of supplying a process gas into the chamber and a solenoidal interleaved parallel conductor coil antenna overlying the ceiling and including a first plurality conductors wound about an axis of symmetry generally perpendicular to the ceiling in respective concentric helical solenoids of at least nearly uniform lateral displacements from the axis of symmetry, each helical solenoid being offset from the other helical solenoids in a direction parallel to the axis of symmetry. An RF plasma source power supply is connected across each of the plural conductors.

Excitation of the 2 3S state of helium by electron impact from threshold to 24 eV: measurements with the `magnetic angle changer'

Abstract: The magnetic angle changer recently invented by Read and co-workers (Read F H and Channing J M 1996 Rev. Sci. Instrum. 67 2373) has been incorporated into an existing electron impact spectrometer. Both the inner and the outer solenoids consist of a single layer of self-supporting thin copper tubing, cooled by circulating water. This construction makes the solenoid nearly optically transparent, reducing the interference of the new device with the flow of sample gas - a feature important for measurements of absolute cross sections and for the operation of a supersonic free jet. The properties of the device are illustrated with measurements of the differential cross sections for the excitation of the 2 3 S state of helium by impact of electrons from threshold to 24 eV. Spectra are presented at the scattering angles of 0°, 45°, 90°, 135° and 180°, important for deriving integral cross sections, and 145°, 155° and 165°, revealing interesting details of the interference of narrow ridge resonances with background scattering at angles surrounding the deep minimum of the angular distribution at 22 eV.

Electromagnetic operating device

Abstract: Disclosed is a solenoid type electromagnetic operating device which needs a relatively large current only for a limited short period at an excitation start initial stage and is adapted to achieve the speeding up at an excitation start stage and an improvement in responsiveness as well as power saving without increasing a power load on each of a drive circuit and power supply. The device is used for exerting a mechanical output on a valve element against a spring force, and comprises a solenoid coil composed of a plurality of split coils mutually electrically independent, an iron core structure including a fixed core, a movable core and a yoke and assembled with the solenoid coil so as to form a magnetic path loop through which magnetic fluxes from the split coils pass in common, an excitation controller for selectively switching/controlling the excitation current to each split coil, and a transmission mechanism for transmitting the mechanical output based on the displacement of the movable core magnetically attracted to the fixed core to the valve element when one or more of the split coils are excited.

Beam envelope equations for cooling of muons in solenoid fields

Abstract: Muon cooling is a critical component of the proposed muon collider and neutrino factory. Previous studies of cooling channels have tracked single muons through the channel, which requires many particles for good statistics and does not lend itself to an understanding of channel dynamics. In this paper, a system of moment equations are derived which captures the major aspects of cooling: interactions with material and acceleration by radio frequency (rf) cavities. A general analysis of solenoid lattice types compares well with prior simulations and indicates new directions for study. (c) 2000 The American Physical Society.

Completion of CS insert fabrication

Abstract: The central solenoid (CS) model coil program is in progress with an international collaboration under the frame of the ITER-EDA. The purpose of the CS insert coil is to test the performance of the ITER-CS conductor. The CS insert coil is installed in the bore of the CS model coil and tested at a magnetic flux density of 13 T. The installation work is underway with the inner and outer module of the CS model coil. The superconducting characteristics of the CS conductor, the critical current and the current sharing temperature are evaluated under the operating load. The AC loss characteristics of the conductor are also evaluated under pulsed magnetic field. The fabrication of the CS insert coil was completed on May 1999. The winding tools and the results of the winding of CS insert coil are reported. The heat treatment for Nb/sub 3/Sn processing was performed successfully with no SAGBO (stress accelerated grain boundary oxidation). The procedure of the heat treatment is also reported.

Laser-assisted fabrication of NMR resonators

Abstract: A detection coil for use in nuclear resonance magnetic (NMR) spectroscopy and a method of manufacture thereof. At least two film layers of material are deposited on an outer surface of a cylindrical tube of dielectric material. The layers are patterned to form a solenoid on the tube. At least one of the deposited materials is a conductor.

Apparatus for remote activation of equipment and demolition charges

Abstract: An apparatus for the activation of a remote device having a transmitter to generate and transmit user-set special coded signals. The transmitter has a function selector switch to select modes of operation for the transmitter. Included is also a receiver to receive the user-set special coded signals, and the receiver also has a function selector switch to select modes of operation for the receiver. The function selector switch selects the following modes of operation for the transmitter: (a) a “transmit/fire” mode that enables a fire signal to be transmitted to the receiver; (b) a “wake-up” mode that enables a set-up receiver mode for immediate firing; (c) a program mode for low power transmission of programmed codes; and (d) a “test” and operational mode that enables an operational test of the apparatus with no firing output. The function selector switch on the receiver selects the following modes of operation for the receiver: (a) receive a “wake-up” of “fire” signal; (b) actuate either an electrical excitation output or an electromechanical solenoid output; (c) provide a continuity test for a blasting cap; (d) program the receiver for receiving programmed codes; and (e) conduct operational tests of the receiver.

Highly sensitive open-flat coil magnetometer for the λ(H,T) measurements in plate-like high-Tc cuprates

Abstract: The “LC resonator” method was greatly improved for high resolution measurements of magnetic-field penetration depth, λ, of radio frequency into thin films or plate-like high-Tc superconductors by replacing a solenoid testing coil by an open-flat coil (OFC) driven by a tunnel diode oscillator of a low power and a highly stable frequency The assembled OFC magnetometer showed new technical advantages such as simplicity, convenience, and high resolution of Δλ∼1–3 A (Δλ/λ∼10−6), ability of reliable operation in wide ranges of temperature (42–300 K) and magnetic field (up to 12 T), etc This enables us to use it for studying peculiarities of the vortex dynamics with weak signal in small sample volume high-Tc cuprates As a first test of the assembled 23 MHz measuring setup, the temperature dependence of the upper critical field, HC2(T), is determined from the magnetic transition curves at different temperatures for Y1Ba2Cu3O7−δ thin-film ring The HC2(T) data obey the formula: [1−(T/Tc)2]β with β=122±003 at

Solenoid coil structure and interconnection

Abstract: A solenoid coil inverted within a flux casing has at least one lead wire extending through a flux ring mounted in an end of the flux casing. The coil is coupled to a circuit board or overmolded lead frame which is positioned adjacent to a valve body with a solenoid valve sleeve extending through the circuit board or lead frame into the coil. A flexible coupling allows the coil to move relative to the circuit board or lead frame.

Image forming device

Abstract: PROBLEM TO BE SOLVED: To maintain an entrance guide and to make steadily performable satisfactory image formation for a long time, by forming, in the vicinity of a solenoid, an air duct for cooling it. SOLUTION: An electromagnetic solenoid 18 is provided near an entrance guide 17, on a base 23 outside the rear side plate 22 of the device. Also, a spring is provided below the entrance guide 17, and the entrance guide 17 is always deviated toward a fixing roller situated above. In the case where stiff transfer materials of a small size are consecutively carried to a fixing device, the electromagnetic solenoid 18 is kept energized for a long time, a gradual temperature increase occurs, the resistance value of the coils of the electromagnetic solenoid 18 changes and attractive force decreases. Consequently, the entrance guide 17 cannot be kept in a high position and a jam or the like is caused. Therefore, air is forcibly exhausted by providing a duct 30 for covering the electromagnetic solenoid 18 and providing a fan 21 at its outer end. This prevents temperature increase of the electromagnetic solenoid 18 and makes it possible to carry out steady fixing at all times.

Apparatus and method for abrasive jet finishing of deeply concave surfaces using magnetorheological fluid

Abstract: Apparatus and method for abrasive jet of a deeply concave surface using magnetorheological fluid A ferromagnetic nozzle recessed within a solenoid magnetically shields the fluid within the nozzle and serves as a core for the solenoid, thereby increasing the strength of the magnetic field approximately 100-fold, permitting a significant reduction in the size of the solenoid The exit orifice of the nozzle is recessed within the solenoid, creating a free space within the solenoid having an intense, shaped, axial magnetic field in and near the nozzle Stiffening of the magnetorheological fluid begins as the fluid enters the magnetic field upon leaving the nozzle; thus, there is no buildup of viscous drag through the nozzle Stiffening of the jet occurs principally in free space within the solenoid The nozzle has peripheral longitudinal channels through which compressed air is conveyed to form an air curtain surrounding the jet, preventing spent MR fluid from re-entering and fouling the nozzle

Integrally mounted pneumatic solenoid valve for wastegate control

Abstract: A turbocharger for internal combustion engines having a valve mount cast or machined integral with the compressor housing (12) and disposed along a compressor housing outside surface, the valve including a first air port (18) in communication, through a restriction orifice, with the compressor volute and at least one of a second air port (40) in communication with the first port, and a third port (20) in communication with the compressor air intake. The mount includes attachments for a solenoid valve (28) to the valve mount and a means for forming a leak-tight seal between the solenoid valve and the second and third air ports. A control system (164) for actuating the solenoid allows venting of pressure from the second air port to the third air port for application in controlling a wastegate actuator (170) or disengaging the wastegate actuator by venting pressure from the first port to the second port.

Electric power supply apparatus for solenoid valve manifold

Abstract: Simple adaptation to change in the number of terminals in a serial unit or the like is made possible in controlling a plurality of solenoid valves by a solenoid valve manifold. An electric circuit section of a connected manifold block 2 having solenoid valves 1 mounted thereon is constructed by electrically connecting, with a wiring on a printed wiring board 34, a multiple-pole male connector 35 disposed on one connecting surface of the manifold block, a multiple-pole female connector 36 disposed on the other connecting surface, and an electric power supplying connector 37 connected to an electric power receiving connector 14 of the solenoid valves. The wiring on the printed wiring board 34 is constructed in such a manner that terminals of the multiple-pole male connector 35 that send driving signals to respective solenoid valves are connected to terminals of the female connector 36 by shifting the driving signals thereof sequentially to terminals on the electric power supplying connector 37 side; the terminal on the utmost end of the shifted side is connected to the electric power supplying connector 37; and a common terminal 57 is disposed at the end of the aforesaid electric power supplying connector side.

Headlight for vehicle

Abstract: PROBLEM TO BE SOLVED: To prevent adverse effects on a light intensity distribution and overload on a solenoid due to vehicle vibrations or the like and easily securing a solenoid mounting space in a headlight for a vehicle constructed to change the light intensity distribution by moving a shade with the solenoid. SOLUTION: A shaft 30 which can reciprocate in a vehicle front and rear direction is connected and fixed to a shade 26, and a plunger 34A of the solenoid 32 reciprocable in a right and left direction crossing at right angles with the vehicle front and rear direction is engaged with the shaft 30 via a pinion unit 34. Accordingly, the solenoid 32 can be arranged in sideways. Further, the weight of the plunger 32A is prevented from participating as an inertia load with respect to vibration load in the vehicle front and rear direction and weights of the shaft 30 and the shade 26 are prevented from participating as inertia load with respect to vibration load in the right and left direction for effectively controlling shaking of the shade 26 due to vehicular vibrations or the like and for preventing an excess load from being applied on the solenoid 32. COPYRIGHT: (C)2001,JPO

High flow solenoid control valve

Abstract: An engine oil solenoid actuated control valve includes a molded one-piece member that defines a check valve-receiving region and a coil bobbin region of the solenoid. The check valve-receiving region includes an integral check valve-receiving receptacle associated with an exhaust port of the control valve. A check valve is received in the receptacle. A solenoid armature is received in the coil bobbin region on which a solenoid coil is wound. The molded one-piece member receives a fluid port-forming sleeve member that provides a supply port and control port. A spool valve is received in the port-forming sleeve member and includes a spool valve end connected to the armature of the solenoid. The spool valve includes first and second lands that are moved relative to the respective fluid supply port and control port to control fluid flow at the control port. A fast response, high flow rate is provided by a preselected gap provided between the end of the armature and a pole piece in the bobbin region together with an annular control port configuration.

3D magnetic analysis of the CMS magnet

Abstract: The CMS magnetic system consists of a superconducting solenoid coil, 12.5 m long and 6 m free bore diameter, and of an iron flux-return yoke, which includes the central barrel, two end-caps and the ferromagnetic parts of the hadronic forward calorimeter. The magnetic flux density in the center of the solenoid is 4 T. To carry out the magnetic analysis of the CMS magnetic system, several 3D models were developed to perform magnetic field and force calculations using the Vector Fields code TOSCA. The analysis includes a study of the general field behavior, the calculation of the forces on the coil generated by small axial, radial displacements and angular tilts, the calculation of the forces on the ferromagnetic parts, the calculation of the fringe field outside the magnetic system, and a study of the field level in the chimneys for the current leads and the cryogenic lines. A procedure to reconstruct the field inside a cylindrical volume starting from the values of the magnetic flux density on the cylinder surface is considered. Special TOSCA-GEANT interface tools have being developed to input the calculated magnetic field into the detector simulation package.