Abstract: A control method and apparatus for suppressing the vibration components of a magnetic bearing. According to this invention, a vibration wave is sampled at pulses synchronized with the rotation of a rotor, the vibration waveform sampled values at each revolution are averaged, and only the frequency components synchronized with the rotation frequency of the rotor are extracted from the vibration waveform. In addition, the extracted components are subjected to Fourier transform, processed in a frequency region and subjected to Fourier reverse transform. The sequence of these signal processes produces a signal, and the vibration components are suppressed by this signal.

Abstract: The present invention relates to apparatus for stabilizing the operation of rotational machinery, particularly machinery which uses magnetic bearings. Accelerometers sense various vibrations within the machinery. The outputs of the accelerometers are analyzed by a Fast Fourier Transform algorithm and multiplied by an array of influence coefficients to calculate desired stabilizing forces to be applied to the rotating machinery. Compensating analog voltage signals are generated in accordance therewith and transmitted to magnetic control coils within the rotating machinery.

Abstract: An active control precision damping table supported by air springs. Level displacement and vibrations of the table are detected by a sensor or sensors, and sensor outputs are fed to a variation adder which carries out an adding operation on one of the sensor outputs and an inversion signal produced by inverting the other sensor output 180 degrees. The adder outputs results of the operation to a drive circuit, which in turn outputs a drive signal to a control valve. The control valve is operable in response to the drive signal to adjust air pressure in pressure vessels of the air springs.

Abstract: An ultrasonic servo controller circuit is disclosed which is used to detect the edge of a web and adjust the web position as it is dispensed from a pay-off roll to packaging machinery. The circuit is utilized to control a motor which operates a linear actuator to "de-oscillate" the web thereby providing the packaging machinery with a steady, non-oscillating sheet of material.

Abstract: Signal-processing apparatus for use with industrial instrumentation systems and the like, and comprising a memory to maintain a signal level for long time periods without drift. An input signal level is translated into the positioning of a movable member, through the use of an actuator motor controlled by the input signal and a position feedback signal. A friction device is coupled to the movable member to hold it in any given position, thereby to serve as a memory for the input signal level. The friction device comprises a thin vane-like element which is secured to the movable member and disposed in the air-gap of a permanent magnet. The air-gap also includes a mass of tiny magnetizable particles which, under the influence of the magnetic field, engage the surfaces of the vane-like element to develop a frictional restraining force.

Abstract: System for accurately positioning an article transfer assembly in a preselected one of several positions in at least one of a horizontal and a vertical path of movement by remotely controlling the assembly by way of a digital position reader unit. A belt control arrangement extends parallel to the paths of movement of the assembly and is provided with a series of mutually separate and locally disposed position-defining control elements, a corresponding series of mutually separate and locally disposed position-indicating control elements as well as a corresponding series of mutually separate and locally disposed locking elements. A carrier arrangement is combined with the assembly and displaceably engages the control arrangement by way of rollers. The carrier arrangement is provided with search devices adapted to cooperate with the position-defining control elements and with the position-indicating control elements and with a locking device adapted to cooperate with the locking elements.

Abstract: Signal-processing apparatus for use with industrial instrumentation systems and the like, and comprising memory means to maintain a signal level for long time periods without drift. An input signal level is translated into the positioning of a movable member, through the use of an actuator motor controlled by the input signal and a position feedback signal. A friction device is coupled to the movable member to hold it in any given position, thereby to serve as a memory for the input signal level. The friction device comprises a thin vane-like element which is secured to the movable member and disposed in the air-gap of a permanent magnet. The air-gap also includes a mass of tiny magnetizable particles which, under the influence of the magnetic field, engage the surfaces of the vane-like element to develop a frictional restraining force.

Abstract: A gyroscope unit having a horizontal spin axis hangs from a suspension band within a container. The container is rotatably supported about a vertical axis. A transducer generates a control signal representative of the angular displacement between the gyroscope unit and the container about the vertical axis from a reference position. The container is rotated about the vertical axis responsive to the control signal to reduce the angular displacement from the reference position. A torque about the vertical axis that opposes the angular displacement is directly applied to the gyroscope unit responsive to the control signal. The directly applied torque is a nonlinear function of the angular displacement, being zero below a threshold value of angular displacement and having a predetermined gradient above the threshold value.