Abstract: A system for rapidly soldering wire to terminal pads of a printed circuit board. A soldering tool is heated to a high temperature above 1000 degrees F., and preferably between 1600 to 2000 degrees F., and has a predetermined effective mass for holding a quantum of heat just sufficient to make an effective solder joint over a broad range of terminal pad conditions.

Abstract: A brushless electric micromotor comprised of a rotor, a shaft and a tube-like part and permanent magnets rotatably mounted and hermetically sealed in a rotor housing, said shaft being supported in bearings. The permanent magnets have their co-axial surfaces coated with a layer of an electrically conductive metal. The micromotor further comprises a stator co-axially surrounding the rotor housing and comprising field windings regularly arranged with equal angular distances in the stator housing made of magnetic material.

Abstract: A brushless D.C. motor control system wherein a read-only memory is used to control the commutated winding energization via drive switching circuits. Position sensors detect the position of the rotor relative to the motor stator and principle digital signals which are used as address inputs for the read-only memory.

Abstract: A servo motor system including a position sensor located within the motor air gap to virtually eliminate mechanical compliance in the servo loop. The transducer is of a capacitive type including interleaved capacitive plates and is designed to be substantially insensitive to the magnetic field of the motor.

Abstract: A linear servo system including a linear motor with a moving permanent magnet the flux of which interacts with current flow through a stator winding. A position servo loop controls the position of the permanent magnet and preferably includes a position transducer located within the motor air gap. The servo system when used in combination with a disk drive preferably includes a coarse/fine positioning program to first move to the desired disk track area and to then move to the center of the disk track. The motor winding located in the air gap can be made of iron or copper clad iron to reduce the size of the effective air gap.

Abstract: A process for extending and fixing conductors to circuit board base surfaces between pre-established spaced points in straight paths and pre-established spaced points in inflected paths, the steps comprising, fixing the end of the conductor to a pad at the first of a pair of pre-selected points and, while feeding the conductor with a guide, moving the board and the guide relative to each other along a straight path to a pad at the second of the pair of pre-established points or to a pad at an inflection point, if the conductor is to be inflected, and then to said second pad. Severing said conductor at said second pad and affixing the conductor end to said second pad. Repeating the foregoing steps until the conductor has been affixed to the pre-established pairs of pads and to the pads at the inflection points.

Abstract: Surfaces of articles are sensitized for the deposition of adherent metal from electroless metal solutions in contact therewith by prior treatment with an activatable complex of copper in a liquid medium formed from a solution comprising a mixture of halogen, cuprous and cupric components and thereafter forming a deposit on the treated article surfaces of a water-insoluble derivative of the said complex. Such surface deposits are treated with a reducing agent or water to enhance their reception of metal in an electroless metal deposition bath.

Abstract: A motor control system wherein the motor windings are energized by sinusoidal excitation currents synthesized from prerecorded sine values. The frequency of the winding excitation currents is synchronous with the rotor movement and the phase is a function of the rotor position with respect to the stator. The phase of the winding excitation is additionally controllable as a function of speed or some other adequate system parameter. It has further been found that the total operational speed range of the system is substantially increased by further adjusting and controlling the phase of the excitation currents as a function of the desired speed.

Abstract: A circuit for driving an electrical load such as an electric motor, by a pulse width modulated current includes a saturable current driver connected to the load. The circuit includes a linear transconductance amplifier with current-sensing feedback for applying a pulse-width modulated control current to the driver. The feedback preserves the extent of saturation and of cut-off by providing current pulses which are invariant with respect to thermally induced changes in circuit parameters. Amplitude and offset control circuitry are also provided for setting the range of current values during the current pulsing to optimize the operation of the driver. In an alternative simplified circuit, a low-level switching circuit drives complementary output transistors operating in a linear fashion, and producing current pulses which are invariant with respect to the saturable driver parameters.

Abstract: A method for producing multiplane circuit boards in which a plurality of planar members, each having a plurality of connecting areas disposed in rows on the planar member, each connecting area having interlinking positions and interrupting positions, with such positions in predetermined locations, are prepared. A plurality of planar members, each having trains of conductors in parallel paths at predetermined locations are also prepared. Such planar members are then stacked, one on the other, with the connecting areas and conducting paths in predetermined position and the stacked planar members are then laminated together. Selected of the interlinking positions and selected of the interrupting positions are then interconnected by drilling the laminate to form the multiplane circuit board.

Abstract: An electric motor is wound with redundant sets of windings which are energized by independent electric circuits to enable operation of the motor even in the presence of a failure of a winding and a failure of an energization circuit. The motor may be of the permanent magnet form with electronic switching of the winding currents in lieu of switching via a commutator, known as a brushless DC motor, in which case separate sensing devices, such as Hall effect devices, are employed with each winding set and energization circuit for sensing the relative position between the moving and stationary members of the motor. The sets of windings, when placed on the stator, are physically spaced apart so as to minimize magnetic coupling therebetween.

Abstract: The present invention relates to a semi-additive or full-additive process for producing printed circuit or conductor boards having improved electrical resistance in which the coating of adhesive medium exposed between the trains of conductors is removed or partially removed without corroding the base material or copper of the conductor trains by a treatment with an alkaline permanganate or chromic acid solution and suitable washing steps carried out subsequently.

Abstract: An improved process for removing resin smeared on an interior wall of a hole in a resinous substrate and/or adhesion promoting the substrate which comprises: (a) contacting the substrate with an alkaline permanganate treating solution having a pH between about 11 and about 13 and an elevated temperature for a time period sufficient to remove the resin smear; (b) neutralizing essentially all manganese residue on the substrate; (c) contacting the substrate with an alkaline hydroxide etchant to remove the balance of manganese residue on the substrate. A metal such as copper subsequently may be electrolessly deposited in a more efficient and easily controlled manner on the resin substrate in the formation of a wire scribed circuit board or multilayer printed circuit board. In addition to resin smear removal, the process results in an improved bond between copper and the hole wall.

Abstract: A method of rapidly relieving stress in an extruded or molded polymer article is disclosed. The method can be used in the preparation of printed circuit boards. An article comprised of the polymer is exposed to electromagnetic radiation, for a time period sufficient to absorb enough energy to stress relieve the polymer against stress cracking therein. Exposure occurs at one or more ranges of frequencies which are capable of being absorbed by the polymer and which are effective for stress relieving without or substantially without causing heat induced softening or flowing of the polymer. The electromagnetic radiation is selected from the ranges of infrared, microwave or ultraviolet radiation.

Abstract: An annular illuminator comprising a spheric mirror, an elliptic mirror and a circular cylindric mirror. Flux received directly from the source is reflected by the elliptic mirror and then by the cylindric mirror. Flux not directed initially toward the elliptic mirror is first reflected by the spheric mirror and then by the elliptic and cylindric mirrors.

Abstract: A bearing structure for use in a linear motor or actuator including only a single guide rod in combination with a freely moving ball bearing. When used in a permanent magnet motor, the magnetic flux of the motor is used to preload the ball bearing to maintain a relatively constant bearing loading and to maintain the ball bearing in position.

Abstract: The metallic surfaces of plating equipment in use during electroless copper deposition, such as vessels, racks supporting substrates being plated, plumbing, and the like are rendered substantially resistant to electroless copper deposition for extended periods by initially imposing on such equipment surfaces an electrical potential more positive than the mixed potential of the electroless copper solution and sufficiently positive to resist electroless deposition, electrolessly depositing copper on the substrate being plated, and while depositing such copper maintaining on the equipment surface a potential sufficiently positive to resist the formation of adherent electroless copper deposits.

Abstract: A method for producing printed circuit boards with holes having walls provided with a metal coating on base material provided with an adhesive layer which, in turn, is covered by a masking foil composed of plastic material or metal. Following the preparation of the pattern of holes and prior to the removal of the masking foil, the layer of adhesive coating is removed at the edges of the holes by chemical action, so that an annular zone free of adhesive is formed underneath the masking foil. The masking foil is subsequently removed and the metallization of the pattern of conductors and walls of the holes is produced by currentless deposition alone or combined with galvanic precipitation.

Abstract: A linear DC permanent magnet motor comprising a wound member having a plurality of windings wound on a slotted magnetic structure and a field member movable relative to said wound member, the field comprising permanent magnet means for developing a magnetic field and means for energizing with DC current at least some of the windings, the magnetic field of said permanent magnet means interacting with the energized windings causing said field member to move relative to said wound member. The motor also comprises support means for maintaining air gaps between the wound member and the field member.

Abstract: A four quadrant control system for a brushless D.C. motor wherein the windings are energized via a drive switching circuit in a bridge configuration and the switching circuit is in turn controlled by a read-only memory. Pulse-width modulation control signals and position signals are supplied to the read-only memory as addresses together with other control signals. The system operates in a regenerative mode when changing direction and automatically makes a smooth transition into a motoring mode when the back EMF of the motor is no longer large enough to satisfy the requirements of the current loop.