Abstract: The present solenoid stator assembly mounts on a seat forming part of a fuel injector, secured to it by mounting bolts. A rigid metal outer housing has a base shaped to fit upon the mounting seat of the fuel injector and defines an interior chamber. An E-shaped stator core is located centrally within the interior chamber and an insulated plastic inner housing extends between the stator core and the outer housing to fixedly secure the core within the interior chamber. The outer housing reinforces the insulated plastic inner housing against the bulging forces imposed by high fuel pressure and protects it against damage from external blows.

Abstract: A magnetostatic field generator for a magnetic resonance imaging apparatus includes a pair of permanent magnets each having a rectangular parallelepiped shape arranged perpendicular to a direction of a uniform magnetic field to surround a space where a uniform magnetic field is generated, a plurality of first permanent magnets each having a trigonal prism shape arranged on both sides of an area between the permanent magnets each having a rectangular parallelepiped shape, a plurality of second permanent magnets each having a trigonal prism shape which are arranged between the permanent magnets each having a rectangular parallelepiped shape and the first permanent magnets and satisfy magnetic field boundary conditions between the permanent magnets each having a rectangular parallelepiped shape and the first permanent magnets, and a yoke for holding the pair of permanent magnets each having a rectangular parallelepiped shape, the plurality of first permanent magnets, and the plurality of second permanent magnets

Abstract: Magnet assemblies for installation into a voice coil motor is described. A pair of magnetic pieces are molded into circular arc shapes of different radii and positioned concentrically across a gap. The ends of such the pair of magnet pieces, are joined to a similarly-molded other pair of magnet pieces. The direction of magnetization of the former pair of magnet pieces is reverse that of latter pair of a magnet pieces. On the upper curved surface of each of the two units of lower magnet pieces of smaller radius, a cut plane, for example, is formed in order to provide unbalanced cubic volume between one half and the other half from the center plane of a magnet piece, thus increasing the gap magnetic flux density being generated inside the gap at the sections of larger cubic volume, thereby improving overall evenness of the gap magnetic flux density distribution.

Abstract: An active shield magnet has a plurality of screening coils which each have a small number of turns in comparison with the number of turns of the main magnet coil assemblies and which are connected in series in a closed loop to reduce the effect of disturbing influences in a working volume of the magnet.

Abstract: In a method for the production of a magnet coil arrangement which can create a predetermined magnet field B and has a minimal inductance L. The magnetic field B to be generated is expanded in spherical harmonics with coefficients C.sub.n,m and a field error .DELTA. B=f.sub.1 (C.sub.n,m) is defined fixing the deviation of the magnet field profile of the coil arrangement to be calculated from the given magnet field B within a volume and, if necessary, further parameters P=f.sub.2 (C.sub.n,m) are predefined, whereby the value of P which is calculated with a particular set of coefficients C.sub.n,m is within predetermined limits. By defining limits for technically relevant parameters and their variation as well as by giving the desired minimum inductance, the procedure achieves a high flexibility in conjunction with independent optimization of the parameters, in particular field errors, minimum inductance and current density oscillations.

Abstract: An electromagnetic apparatus has a housing with a cavity in which a uniform magnetic field is created by a magnetic coil disposed in the housing. The electromagnetic apparatus also has one or more containers for containing magnetic substances for adjusting the intensity distribution of the magnetic field in the cavity so as to obtain a uniform intensity, and clamps attached to the housing for detachably mounting the containers. During adjustment of the magnetic field in the cavity, a container is removed from the clamps, magnetic substances are added or removed, then the container is mounted in the clamps again.

Abstract: A solenoid comprising a first coil positioned within a frame from which a magnetizable armature, having a coil end and a free end, extends, the coil end of the armature having a section of non-magnetizable material secured to it, and a second coil, which coil is energizable in a manner independent from that of the first coil, the second coil being secured to the other end of the non-magnetizable material so as to move with the armature from a position adjacent the first coil when the armature is in extended position to a position spaced therefrom when the armature is in retracted position, whereby when the first coil is energized to move the armature along its throw into retracted position, the second coil is simultaneously energized so as produce a repulsive magnetic force with respect to that of the first coil.

Abstract: The invention concerns a superconducting high field magnetic coil for the production of magnetic field with one or more approximately rotationally symmetric hollow cylindrically shaped winding regions made from layers of windings of a superconducting wire through which current is flowing whereby in axial end regions of at least one winding region, radial components of the magnetic field are present which lead to axial Lorentz forces as well as to the accumulation of axial pressures in the winding layers. According to the invention, in the axial end regions of at least one winding region, the current density in at least one winding layer (S3, S4) is reduced relative to the normal current density present in the region bordering on the end region so that, thereby, the maximum Lorentz force occurring in these winding layers as well as the maximum occurring axial pressure is maintained within permissible limits.

Abstract: A magnetizing apparatus capable of magnetizing a magnetic roller having a length up to 30 cm is provided. The magnetizing apparatus is comprised of at least two split members, each of which is provided with magnetic heads employed for applying magnetic fields to a magnetic roller. The end face of each magnetic head is shaped in agreement with the profile of the magnetic roller so that there would be no air gap formed between the magnetic head and the magnetic roller when they come into contact with each other. The split members are separated first and then combined to accommodate the magnetic roller within the magnetizing apparatus. After magnetization, a magnetic force is induced between the magnetic head and the magnetic roller such that an external force stronger than the magnetic force is used to pull the split members apart to fetch out the magnetic roller.

Abstract: A tubular structure having a transverse magnetic field that varies in eit the longitudinal direction or the lateral direction. In one embodiment, a permanent magnet tubular structure has a working magnetic field space that is partially bounded by pole pieces that reduce the height of the working magnetic field space. A laterally varying magnetic field is formed within the tubular structure. In another embodiment, a permanent magnet tubular structure is comprised of sections made of a permanent magnetic material, each section having a different remanence. The adjacent sections, having different remanence, form a linear array resulting in a longitudinally varying magnetic field gradient within the working space. The present invention has many practical applications such as in magnetic resonance imaging.

Abstract: The present invention provides an improved magnetic levitation system for the stable or rigid levitation of a body. The object to be levitated is maintained in an equilibrium position above a flat guideway or a plurality of continuous guideways. The rigidity of the levitation is at least in part achieved by the orientation of the axis through the poles of the magnet in a direction perpendicular to the direction of relative motion between the magnet and the conductor.

Abstract: This invention relates to an apparatus and method for providing passive shimming for a superconducting magnet of the type that has a relatively small imaging volume. Such structures of this type, generally, provide the proper amount of passive shimming for a relatively small imaging volume.

Abstract: An MRI magnet member (e.g., a pole piece or tip) is laminated using relatively large bar-shaped laminations instead of the usual thin sheet material. One or more layers of such bar-shaped laminations are arrayed with small insulating gaps into which a low loss insulating liquid filler material is flowed and then cured to a hardened solid state. This simultaneously produces insulated pole tip laminations which have been robustly integrated together into a unitary structure. The resulting robust laminated pole tip is relatively easy to manufacture and is also capable of withstanding rather large magnetic forces and maintaining relatively uniform magnetic field distribution within an MRI imaging region while yet providing providing sufficient eddy current reduction so as to efficiently permit rapidly changing magnetic gradient coil currents to be established.

Abstract: A C-shaped superconducting magnet for use in magnetic resonance imaging (MRI) equipment is disclosed. The magnet includes flux concentrators on opposing sides of the gap, for generating a vertical field therein; the flux concentrators include a plurality of coils, for carrying current in opposing directions, so as to generate an inwardly directed field to compensate for the gap. Injection correctors, each consisting of a horizontal coil, are disposed adjacent the flux concentrators. A flux return body, for example a superconducting solenoid or an iron yoke, provides a return path on the opposite side of the magnet from the gap. Flux deflectors guide return flux in a curved path from the flux return body to the injection correctors.

Abstract: An alternating current magnetic levitation transport system transporting a floating body made of conductive paramagnetic or nonmagnetic metallic material being levitated over alternating current electromagnets by making use of repulsion of an alternating electromagnetic field, comprises a tubular passage provided over the alternating current electromagnets which are spatially cut off from the outside wherein the floating body is levitated and transported. A cooling system made of a conjoined body of a thermoelectric cooling thermomodule and a liquid-cooled heat exchanger is provided in the transport system in contact with said tubular passage. This system can be favorably used in a clean environment where dust generation has to be avoided and the system can thereby provide more efficient transportation.

Abstract: A method of trapping a field in a block of superconductor material, includes providing (i) a block of material defining a bore, (ii) a high permeability core within the bore that defines a low reluctance path through the bore, (iii) a high permeability external structure on the exterior of the block of material that defines a low reluctance path between opposite ends of the core, and (iv) an electromagnet configured to apply a magnetic field around the high permeability core. The method proceeds by energizing the electromagnet to produce an applied magnetic field around the high permeability core, cooling the block of material sufficiently to render the block of material superconducting, de-energizing the electromagnet to result in a trapped magnetic field, and at least partially removing the low reluctance path defined by the core and the external structure in order to increase the magnetic flux density of the trapped magnetic field.

Abstract: A flexible castellated joint is included in the shim lead assembly electrically connecting the cryostat pressure vessel and the outer vacuum vessel in a superconducting magnet to accommodate relative motion between the two vessels during transportation of the superconducting magnet.

Abstract: In an electromagnetic coupling apparatus, an excitation coil constituted by a plurality of turns of a winding member is covered with a resin coil bobbin. The coil bobbin can be divided into at least two members and is formed into a hollow annular shape. The divided mating surfaces of the members constituting the coil bobbin are joined to each other by ultrasonic welding.

Abstract: A superconducting coil incorporated in the superconducting magnet apparatus of the invention is shaped annular or cylindrical, and thus surrounds a photographing field. The coil has an axis which is substantially perpendicular to the line of gravity, i.e., extending in the horizontal direction. The coil is contained in a coolant vessel of a double structure filled with a coolant (e.g. liquid helium). Specifically, it is contained in a first coolant vessel, together with a predetermined small amount of liquid helium. The vessel has a receiving space defined therein and shaped similar to the coil. The space is large enough to receive the coil and the coolant with a predetermined gap.

Abstract: A high-speed impact hammer type solenoid capable of operating at high speed such as 500 to 1000 strokes per second and with a relatively long stroke length. It is housed in a cylindrical shell and includes two separate coils and magnetic circuits operating on a single short plunger. The plunger is driven magnetically in both directions. The short plunger has reduced mass. This is made possible by elongated backstops extending through the coils to the plunger and by a flux washer extending from the shell to the plunger. Close control of the plunger stroke is achieved by a non-magnetic sleeve surrounding the plunger and spacing the backstops which are screw threaded into the shell. Resilient anti-residual pads on each side of the plunger absorb the impact of the plunger with the backstop, start the plunger in the opposite direction and speed up the decay of the magnetic field.