Abstract: A limited excursion permanent magnet motor in which the permanent magnet, captured between axially loaded bearings, is connected in a space-economizing construction to the output shaft of the motor by a torque-transmitting keyed construction.

Abstract: An analog optical position transducer for detecting angular position of a rotatable member of a motor. The transducer includes a plurality of sensing surfaces placed in one frame of reference and a modulator located in another frame of reference, one of the frames of reference being stationary and the other moving with the rotatable member. The relative angular position of the two frames of reference is determined from the amount of light varied by the modulator and detected by the sensing surfaces. The modulator employs a radiation source which is located on a diffusive surface or which irradiates the diffusive surface of the modulator. Radiation emitted from the diffusive surface is modulated by the modulator depending on the relative position of the modulator and the sensing surfaces. A lens focuses the emitted radiation onto the sensing surfaces.

Abstract: A confocal microscope (10) includes a scanner assembly (38) in which the x-axis deflector assembly includes two resonant scanners (50 and 52) that oscillate about parallel axes at different frequencies, one of which is a harmonic of the other. As a consequence, the x-axis scan can be nearly linear even though it is provided resonantly and thus benefits from the high-speed capabilities of resonant systems. A galvanometer (64) pivots the housing of one of the resonant scanners (50) about its axis so as to provide x-axis panning.

Abstract: To provide the necessary vertical motion of a wire- bonding head (20) mounted on a flexural pivot (16), a wire-bonding machine (10) includes an actuator comprising a permanent magnet (56) mounted on the flexural pivot (16) and extending into the central passage (49) of a ferromagnetic sleeve (46) in which two oppositely wound coils (50 and 52) are mounted. The magnetic force resulting from current flow through the coils (50 and 52) causes the head assembly (18) to pivot about the flexural-pivot axis (16) and thus cause the magnet (56) to move out of symmetry with respect to the ferromagnetic sleeve (46). The resultant attraction between the permanent magnet (56) and the ferromagnetic sleeve (46) tends to counteract the resistance of the flexural pivot (16) to pivotal displacement from a rest position but does not additionally reduce the stiffness of the flexural pivot to other, undesired modes of motion.

Abstract: A two-dimensional scanner employs first and second pivotable mirrors (36 and 40) to control the position of the target point that a light spot assumes in a target plane (44). The second mirror (40) is driven in a resonant mode. An f.multidot..theta. lens (42) converts the pincushion error that would otherwise result into a barreling error, which can be compensated for by controlling the amplitude of the second mirror's oscillations.

Abstract: A variable-capacitance transducer detects the angular position of a rotatable member. The transducer includes a first capacitance plate having a plurality of electrically conductive capacitance electrodes, a second capacitance plate spaced therefrom, and a dielectric element located between the plates. At least two of the electrodes are interconnected by a conductive trace. The dielectric element or one of the plates is fixedly mounted on the rotatable member. The electrodes on the first capacitance plate, in conjunction with the second capacitance plate, form a plurality of capacitances that vary as the angular position of the rotatable member changes. A conductive guard partially envelopes the conductive trace and a conductive guard partially envelopes the electrodes on the first capacitive plate.

Abstract: A two-dimensional scanner employs first and second pivotable mirrors (36 and 40) to control the position of the target point that a light spot assumes in a target phase (44). The second mirror (40) is driven in a resonant mode. An f.multidot..theta. lens (42) converts the pincushion error that would otherwise result into a barreling error, which can be compensated for by controlling the amplitude of the second-mirror oscillations.

Abstract: The natural resonant frequency (and phase) of a resonant mechanical system (having an spring structure that includes a material whose elastic properties change with temperature, e.g., by at least 0.05% per .degree.C.) is tuned to a desired value by changing the temperature of at least part of the spring structure. A two-dimensional image is generated on a surface by tunign a resonant driver (having such a temperature sensitive element) to a natural resonant frequency in coordination with modulation of a beam that is raster scanned on the surface by the resonant driver.

Abstract: Radial free play is reduced in rotor bearings of a limited rotation electromechanical actuator of the kind having a stator assembly with a plurality of stator pole faces, a rotor with a plurality of rotor pole faces, two bearings supporting opposite ends of the rotor and means for establishing magnetic flux across the gaps. In various aspects, the stator and rotor pole faces are cylindrical and the central axis of the rotor pole faces is tilted relative to the central axis of the stator pole faces; a region of a gap between the stator and rotor pole faces produces both the radial free-play-reducing forces and at least part of the driving torque; the gap rotor varies in size along its length but nowhere is so great as to have an effectively infinite reluctance; the gap varies continuously along its length; and each bearing has radial free play equal to at least 10% of twice the difference in the diameters of the stator and rotor pole faces.

Abstract: A mount for attaching an optical element to a rotating shaft combines a first portion which bears the optical element and is sufficiently rigid to limit dynamic distortion of the optical element, a clamp portion spaced axially from the first portion for clamping the mount to the shaft using a force which causes mechanical distortion in the clamp portion, and a strain decoupling means connecting the first portion to the clamp portion and configured to transmit rotation of the shaft faithfully to the element, while isolating the mechanical distortion in the clamp portion from being transmitted axially to the first portion.

Abstract: In an actuator having a stator assembly which defines a pair of stator pole faces, a permeable rotor assembly which is positioned to rotate relative to the stator assembly, and which defines a driving pole face separated from each of the stator pole faces by a flux permeable driving gap, the rotor assembly having an operational range of rotor angular positions over which drive flux passing across the driving gap drives the rotor assembly, the extent of the driving gap at one of the stator pole faces being reduced as the rotor assembly rotates toward the limit of the operational range, the improvement including a flux-permeable compensating gap between the driving pole face and each stator pole face which provides a secondary path for drive flux as the rotor assembly rotates toward the limit of the operational range, the compensating gap being less permeable than the driving gap.

Abstract: An optical element positioner in which a carriage holding the optical element is driven in response to electrical control signals to selected locations along an optical path by a moving-iron, limited-rotation actuator, with the reflected load inertia substantially matched to the actuator rotor and crank arm inertia.

Abstract: An optical scanner or actuator comprising an armature which includes a movable, closed electrically conductive loop, the armature being mounted to rotate about a support axis, current inducing means associated with the electrically conductive loop comprising a stationary flux-conductor extending through and in current-inducing relationship with the loop, and drive means adapted to induce a magnetic current-inducing flux along the flux-conductor in accordance with desired movement of the armature, permanent magnet biasing means comprising a permanent magnet adapted to produce a magnetic field with which current in the electrically conductive loop interacts to cause movement of the armature, one pole of the magnet being permeably connected to one portion of the flux-conductor at a region remote from the electrically conductive loop, and the other pole of the magnet being permeably connected with the flux-conductor via a permeable gap in which a segment of the electrically conductive loop is arranged to move, wh

Abstract: A limited-rotation actuator in which the rotor pole faces and corresponding stator pole faces are spaced apart along the axis of rotation, the rotor pole faces are permeably connected by a flux path having an axial component through the rotor, and the rotor and stator pole faces each subtend an angle of between about 90.degree. and about 180.degree. around the axis. The invention enables wide angle excursions of the rotor and inexpensive fabrication.

Abstract: The invention relates to a limited rotation galvanometer having a shaft adapted to be deflected in accordance with an electrical drive signal applied to the galvanometer, the galvanometer comprising a stator assembly formed of at least one stationary permanent magnet and at least one pole piece cooperatively arranged about a hollow bore, a rotor associated with the shaft and mounted to turn in the hollow bore, and an electrical winding wound about the pole piece and adapted to receive the drive signal, this stator assembly and rotor defining magnetic circuitry for operation of the galvanometer, the deflection of the rotor being dependent upon the rigidity of the stator assembly and the value of the torque applied between the stator assembly the rotor by the application of the drive signal to the winding.

Abstract: A subfractional horsepower, permanent magnet motor has a stator assembly with a pair of axially aligned stator coils in stacked relation, and complementary metal housing members that enclose the coils and define a series of stator poles. An elongated sleeve disposed within the annular stator assembly provides, with the metal housing members, magnetic circuits that surround the stator coils. The stator sleeve is disposed over and interfitted with a frame core that has significantly greater thermal conductivity than the thermal conductivity of the stator sleeve. A channel extends from at least one of the stator coils along the axial length of the core to the base, and the leads of that coil extend radially inward from the coil and along the channel to the base and therefrom externally of the motor.

Abstract: A device for providing a voltage indicating the angular velocity of rotation of the armature in a limited rotation, polarized, moving iron galvanometer. The device includes a means for providing a first voltage dependent upon the angular velocity of the armature, the self-inductance of the galvanometer drive coil, and the drive current in the drive coil. A compensation coil is magnetically coupled to the drive coil and magnetically isolated from the effects of the rotating armature to provide a second voltage which is dependent upon mutual inductance between the drive and compensation coils and upon the drive current, but is not dependent upon the effects of the rotating armature due to the magnetic isolation of the compensation coil from the armature. A combining means proportionally combines the first and second voltages to provide a voltage indicating the angular velocity of rotation of the armature.

Abstract: A subfractional horsepower permanent magnet synchronous motor comprises an annular stator and a cup-form permanent magnet rotor defining an internal cylindrical volume. The rotor is supported for rotation within the stator about the axis of the motor and with an annular air gap between the stator and the cup-form rotor, and means including a stator coil is adapted to be energized to rotate the rotor relative to the stator. An output shaft coaxial with the rotor extends outwardly from one end of the stator, and a stationary support bushing for the output shaft extends into the internal volume defined by the rotor. A gear train is mounted in the space between the inward end of the support bushing and the closed end of the cup-form rotor, and is coupled between the rotor and the output shaft to provide a predetermined speed reduction ratio between the rotor and the output shaft.

Abstract: A bearing free oscillation motor has a stator component that defines a cylindrical cavity and a rotor component with a cylindrical portion disposed within the cavity and spaced from the cavity wall by an annular gap of radial width in the range of one-five percent of the diameter of the cylindrical portion. The rotor is supported for rotation about its axis by attachment to one end of a torsion shaft that is fixed at its other end to the stator. The motor may be of either the moving coil or the moving magnet type, that is a permanent magnet provides a magnetic field across the annular gap and electric current flow through a drive winding interacts with the magnetic field to produce a torque that rotationally deflects the rotor. Disposed in the annular gap between the stator and rotor is a low viscosity liquid that produces essentially no viscous damping, for example a hydrocarbon oil, a silicone oil or a polymeric liquid.

Abstract: Moving iron limited rotation motors, and recorders employing such motors, in which a velocity sensor structure is axially spaced from a drive structure that is shorter than another drive structure of the drive system. In the preferred embodiment shown, a motor having a pair of diametrically opposite drive structures, the sensor is positioned opposite to the end of the longer drive structure and cooperates with it and a coextensive portion of the rotor in defining flux paths. A pair of permanent magnets extend the full length of the drive-sensor structure, supplying flux to both parts.