Abstract: In a sensor having a drive winding for establishing a forward field, an electrically conductive screen is displaceable relative to a sense winding. In the presence of the drive field, eddy currents are generated in the screen to establish a counter-field opposing the forward field, so that the sense winding is shaded by the screen to a varying extent during relative displacement of screen and sense winding and the voltage induced in the sense winding is accordingly correspondingly varied. Application of a high frequency input to the drive winding results in a modulated output from the sense winding which may be demodulated to provide a signal indicative of screen position relative to sense winding. The position signal may be further processed to provide a speed signal. The sensor may assume a multiplicity of linear or planar, rotational and axial or solenoidal configurations.

Abstract: Method and system for phase comparison which uses a ramp-form signal generated from a reference frequency signal and a sampling pulse train signal synchronized with an input signal whose phase change is to be detected. The reference frequency signal, through a dividing circuit is normally utilized for generating the ramp-form signal while a shift pulse signal is generated when a phase of the sampling pulse train signal is deviated outside a predetermined section of each ramp portion of the ramp-form signal, and utilized for generating the ramp-form signal. By this feature, sampling times of the ramp-form signal are always maintained within the predetermined section of each ramp portion of the ramp-form signal even if a frequency of the input signal deviates very widely from the frequency of the reference frequency signal.

Abstract: A digital proportional-integral controller for controlling the speed of a d.c. electric motor in a copying machine and synchronizing it with the speed of another motor in the copying machine. The proportional stage and the integral stage of the controller are each formed by an up/down counter which counts up or down depending upon the pulses of the actual speed signal and the reference signal. Logic circuits are provided for processing the speed signal pulses and the reference signal pulses before they are fed to the up/down counters. The controller also has an interface for a two-wire bus system over which data and commands for adjusting and varying the control parameters can be input.

Abstract: A load support servomechanism circuit controls the armature of a shaker apparatus. The circuit includes a position sensor, peak detectors connected to outputs of the position sensor, an A/D converter connected to outputs of the peak detectors through a switching bank, a power supply and a microprocessor which provides clock, read, write and ready signals and which automatically controls the position of the armature through solenoids operating on an exhaust valve and a pressure valve. Manual operation of the shaker armature is also provided.

Abstract: The invention comprises an automated system 10 for the accurate positioning of movable parts bins 16 in relation to a preferred fixed location 26. The automated system consists of a number of movable parts bins 16 arranged on a conveyor 14 which is driven by a drive mechanism 18. The drive mechanism 18 controllably moves the conveyor 14 and therefore the bins 16 to desired locations in association with a coarse position sensor 24 and a final approach sensor 26. Both the sensors and the conveyor drive mechanism are interconnected with an electronic controller 28. This electronic controller monitors the position sensors in order to control the drive mechanism in a manner which positions the preselected parts bin at the desired location.

Abstract: A low pressure control system for chemical vapor deposition (CVD) apparatus, including a vacuum pressure chamber and an exhaust pump, is provided by a vacuum pump DC motor which is supplied power from a DC motor speed controller coupled to a DC control input signal from a pulsewidth modulation DC converter. The converter receives a single pulsewidth modulated pulse train having its percentage of modulation controlled in accordance with a DC to pulsewidth modulation controller which operates in accordance with the difference between a pair of DC input signals corresponding to the actual pressure inside the vacuum pressure chamber and a desired or set point pressure respectively. The vacuum pump motor speed and accordingly the exhaust pump is controlled with a high degree of precision, thereby providing improved coating uniformity of semiconductor wafers being fabricated by the CVD apparatus.

Abstract: A permanent magnet armature is arranged to be moved initially in spaced proximity to an induction coil connected in an electric circuit across the series arrangement of a source of electric potential and an electronic switch such that when the moving magnetic field of the magnet cuts the coil turns the resulting induced current operates the switch momentarily to connect the source of electric potential across the coil. The resulting current flow through the coil produces a magnetic field which is imposed upon the moving magnet such as to accelerate its movement. An RC time constant circuit is connected across the coil to establish the time period of battery connection across the coil.

Abstract: A control system and method including an integrator coupled with a rate-varying multiplier which operate in parallel with a conventional controller. Because the integration is rate-variable, the resulting control system has the benefits of an integral position control without the problems of integral windup and subsequent overshoot. The system and method have less following and steady state error, faster settling time and better tolerance to noise than traditional PD and PID controls in controlling dynamic manipulators such as robots. Also, because the integrations are performed in a rate-variable manner, errors due to mechanical static friction, i.e. "sticktion", are substantially reduced without sacrificing dynamic performance of the system.

Abstract: A servo system intermittently samples servo sectors from a data disk to obtain the position of the read/write head and to maintain an on-track alignment. A glass scale measures the movement of the transducer head and provides a velocity signal. An integrator integrates the velocity signal to produce a fill-in position signal. This fill-in position signal is added to the position signal from the last sampled servo sector to provide a position compensator with position information when the head is in between servo sectors. An on-track detector circuit and a damping circuit heavily damp movement of the transducer head when the head is in the on-track position. A gain circuit modifies the signal going to the position compensator in order to compensate for misclamping and imperfections in the data disk. The position compensator includes a tilt circuit which compensates for tilting of the disk drive from a non-horizontal position.

Abstract: A system for driving a motor, comprising a DC power supply source, a chopper apparatus switching voltage of the DC source to convert it into predetermined voltage and a shunt DC motor, wherein an armature and a field winding are connected in series and both ends of the series circuit are connected to the positive and negative terminals of the DC source and at the same time voltage at the junction point between the armature and the field is controlled by the chopper apparatus, is provided.

Abstract: An analog servo system suitable for accurately controlling the carriage speed of a high speed printer over a relatively wide range. The system includes an analog tachometer with circuit means which enables the tachometer to operate in either a high gain mode (used at normal or lower carriage speeds) or a low gain mode (used at higher carriage speeds). The tachometer gain mode (or "electronic gear") is controlled by an external command signal such as a single bit supplied by the control microprocessor of the printer. The state of the command signal controls a time constant in the tachometer circuit means which determines the gain mode.

Abstract: An apparatus and method is disclosed for controlling motion of a tape dispensing apparatus or the like in response to both computer change in position signals and proportional and integral tracking error signals to maintain a desired conformal relationship between the tape dispensing apparatus and a contoured surface. The level of responsiveness to computer change in position signals versus tracking error signals is adjustable depending upon the severity of the contour so as to optimize servo tracking where necessary.

Abstract: In a system for controlling the motion of an industrial robot, a resultant translational velocity of a preselected point on the robot is calculated from a plurality of velocity values such as actual velocity values detected by sensors or target velocity values computed from a velocity reference value. Upon the exceeding of a predetermined maximum velocity by the calculated resultant velocity, all robot motion is terminated. Robot motion may also be stopped upon detecting an excessive difference between an actual angular velocity of one robot component and a respective desired or target angular velocity of that robot component, upon detecting an excessive translational acceleration of a predetermined point on the robot, or upon detecting a position of the robot part or point located more than a predetermined distance from a reference position.

Abstract: An NC apparatus in which a single interface is used in common with both an NC operation board and a machine operation board to thereby reduce the apparatus in size and the interfaces in number. A run code generator is provided on the machine operation board, which is removably connected with the interface, for putting the controlling program, which is the high-level language program, into the run state. The interface is a serial interface, preferably an RS-232 type interface.

Abstract: In a rotary compressor provided with a motor to be controlled by an inverter, the power-supply frequency or impressed voltage during one rotation of the induction motor is varied in accordance with the changes in the load torque to make the production torque of the induction motor correspond to the changes in the load torque so as to fundamentally and effectively reduce the oscillations which are caused by the load torque changes.

Abstract: There is disclosed herein an apparatus and method for generating a first signal related to the rate of change of a second signal. In particular, a system is disclosed for generating a velocity signal in a sampled data servo system. The apparatus uses three track and hold amplifiers one of which is also a difference amplifier to sample the position error signal at selected times. A "present" track and hold amplifier samples and holds the position error signal during the current frame. After this is done, during the same frame, a "summing" track and hold amplifier having its difference inputs coupled to the outputs of the "present" track and hold amplifier and to a "previous" track and hold amplifier samples the difference between the present position error signal and the value of the position error signal during the previous sample frame. This difference divided by the sample period gives the velocity.

Abstract: A rotation detecting apparatus for a rotary machine such as a DC motor, the apparatus including a magnet having a plurality of magnetic poles which rotates along with a rotary shaft of a rotary machine, electromagnetic conversion elements disposed in the magnetic field of the magnet, inductance elements disposed in the magnetic field, the inductance elements being spaced with a predetermined interval from the electromagnetic conversion elements, and an electric circuit for obtaining a voltage proportional to the number of rotations of the rotary machine, signals in proportion to the output voltages of the electromagnetic conversion elements and inductance elements being used as input signals to the electric circuit.

Abstract: A high speed machining controller comprises an acoustic emission sensor which is installed in or near a machine for machining a work piece in a high speed and which detects acoustic emission generated during machining a work piece; a signal processing means which is composed of a band-pass filter for passing an element of a frequency band corresponding to the acoustic emission by inputting a signal outputted from the acoustic emission sensor, a rectification circuit for rectifying a signal outputted from said band-pass filter, a peak detection circuit for detecting peak values of the signal outputted from the rectification circuit, and a smoothing circuit for smoothing output signals of said peak detection circuit and for outputting a signal corresponding to the amplitude of the acoustic emission for the purpose of processing the output signal of the acoustic emission sensor to detect its amplitude; a cutting condition discrimination means for judging the cutting condition of a work piece by comparing a detec

Abstract: A focus servomechanism control system in an optical disc is provided for controlling a light focusing unit to adjust a focus of light impinging on a track in a rotatable optical disc. The focus servomechanism control system includes: a unit for moving the light focusing unit in a direction perpendicular to a plane of the optical disc; a unit for producing a focus error signal; a unit for producing a track error signal; and a unit for controlling a position of the light focusing unit through the light focusing unit moving unit in response to the focus error signal and the offset parameter. The focus servomechanism control system further includes an offset setting unit for continuously setting, during an offset adjustment mode, a plurality of offset parameters to the position control unit, to determine a maximum amplitude of the track error signal, and to set the offset parameter producing the maximum amplitude of the track error signal to the position control unit.

Abstract: The position of a rotating element is controlled by a galvanometer and a servo system. The position of the rotating element is determined by using a two-grating moire pattern. Movement of the element causes a projected scale image representing radiation reflected from the element to shift relative to a fixed grating thereby generating moire fringes. The accumulated fringes serve to measure absolute position and motion of the element. The servo digitally processes the measured position to generate several force components which are then combined to control the amount of force applied by the galvanometer to rotate the element.