Abstract: A driving apparatus of a linear motor which reciprocally drives a movable element supported by an elastic member, includes an inverter that converts a direct current power into an alternating-current power with a specified frequency to drive the linear motor, a current detector that detects the output current of the inverter, a voltage detector that detects the output voltage of the inverter, an amplitude detector that detects an amplitude of the movable element of the linear motor, an amplitude controller adjusts the output current or output voltage in a first control cycle so that the amplitude of the movable element is a desired constant value, and a resonant controller that adjusts the output frequency of the inverter in a second control cycle which is larger than the first control cycle so that the output current of the inverter is substantially minimum on condition that the amplitude is substantially constant.

Abstract: A free piston gas compressor comprising a cylinder, a piston reciprocable within the cylinder and a reciprocating linear electric motor derivably coupled to the piston having at least one excitation winding. A measure of the reciprocation time of the piston is obtained, any change in the reciprocation time is detected and the power input to said excitation winding is adjusted in response to any detected change in reciprocation time.

Abstract: In a driving apparatus of a linear compressor 1 having a power source capable of controlling output current and measuring output electric power, frequency of the linear compressor 1 is controlled such that the amplitude of current which is supplied to the linear compressor 1 is made constant and electric power which is supplied to the linear compressor 1 becomes maximum. With this, it is possible to drive the linear compressor 1 efficiently while following the resonance frequency which keeps varying with variation of a load. Further, a current detecting means 8 capable of detecting output current and electric power from inverter input current is provided, and it is unnecessary to newly add a current sensor.

Abstract: A rocking seat control apparatus for a moveable seat supported and having a magnetic member attached thereto is provided that is capable of maintaining the seat being rocked constant in rocking amplitude. The apparatus includes a solenoid for bi-directionally attracting the magnetic member to cause the seat to move in a positive and a negative direction alternately and thereby to be rocked; an amplitude measuring means for measuring an amplitude of the seat being rocked and a rocking motion of the seat; an amplitude damping factor measuring means responsive to displacements in the positive and negative directions of the seat being rocked for measuring an extent of damping factor of the amplitude caused while the seat is being rocked; and a solenoid energizing means for energizing the solenoid means during a time period in which the seat is being rock traveling a distance that is a product of the measured rocking swing and the measured extent of damping factor of amplitude.

Abstract: A controlling apparatus for controlling a linear oscillation motor includes a sensor and a controller. The motor has a movable element and a stator one of which includes an electromagnet with a winding. The sensor is configured to detect movement of the movable element. The controller is configured to intermittently supply electric power to the winding of the electromagnet to move the movable element reciprocally and linearly. The controller is configured to begin each intermittent supply of electric power to the winding at a timing before a dead center of the movable element based on an output of the sensor.

Abstract: An apparatus for controlling an electromagnetic parts feeder comprises a vibrating unit provided with an electromagnet that vibrates at a predetermined frequency, a bowl adapted to discharge parts accommodated therein by means of the vibrating unit, a driving circuit for driving the electromagnet, and a control unit for outputting a driving signal to the driving circuit to cause a predetermined driving. The control is performed by idling the driving of the electromagnet temporarily at every predetermined driving cycles thereof and controlling the vibration of the electromagnet based on a signal obtained from a coil of the electromagnet by its electromagnetic induction during the idling period, for instance, based on a phase difference between a waveform of this signal and the driving signal of the driving circuit.

Abstract: A thread guide (33) for traversing and guiding a thread (5) in a rotating winding bobbin (1) for producing a cross-wound bobbin in a bobbin winder of a textile machine by controlling vibrations of the thread guide. The thread guide (33) is permanently and directly connected to at least one energy accumulator (20,21) throughout the entire traversing motion. The potential energy of the energy accumulator (20,21) increases continuously after the dead center of the traversing area. A substantially harmonious oscillating mechanical system is thus formed with the thread guide.

Abstract: An improved self-oscillation system for a linear oscillatory actuator composed of a stator and a reciprocator. The stator carries a winding to which an electric current is periodically supplied for making a resonant oscillation of the reciprocator. The system includes a self-oscillation circuit for continuing the resonant oscillation of the actuator by a positive feedback manner based upon a back electromotive force (Vbemf) appearing across the winding. The system further includes a PWM control for increasing the electric current in response to a decreasing oscillation amplitude due to an increasing load applied to the reciprocator. A detector circuit is included to monitor the oscillation amplitude of the reciprocator and provides a corresponding detector output in response to which the self-oscillation circuit provides a drive pulse of varying pulse width for making the PWM control.

Abstract: An apparatus for controlling the tension of a traveling yarn includes a rake tensioner having stationary and displaceable yarn tensioning elements in engagement with the traveling yarn, and an electrical coil to which electrical current is supplied by a regulating device. The displaceable yam tensioning elements and the electrical coil are disposed on a common pivot lever. The electrical coil is pivotable in an air gap through which magnetic field lines pass. The tension of the traveling yarn is controlled as a function of the current supplied to the electrical coil. The present invention, thusly, improves the control of the tension of the traveling yarn in spinning or bobbin winding machines.

Abstract: A field orientation control method for an AC motor, which includes assuming an arbitrary axis as an estimated control axis in the synchronously rotating reference frame; injecting a high-frequency fluctuating signal to the estimated control axis; determining the position of a control axis using current, voltage or impedance on the estimated control axis in the synchronously rotating reference frame, generated by the injected high-frequency signal; and determining the position and speed of the rotor based on the control axis thus located. Since this method uses the variation of impedance caused by the induction machine's generation of field and by various shapes, the control performance is more stable than other conventional control methods. This AC motor's control method may be applied to control of torque, speed and position at a low speed where it is difficult to affix a detector and where a highly efficient operation is required.

Abstract: A linear compressor driving device for linear compressor driving a piston in a cylinder by means of a linear motor to generate a compressed gas, has an inverter for outputting an alternating current to be supplied to the linear motor; current detecting means for detecting an output current from the inverter; voltage detecting means for detecting an output voltage from the inverter; current amplitude value determining means for determining a current amplitude value of the output current; output power calculating means for calculating an output power from the inverter based on the detected output current and the detected output voltage; frequency determining means for determining a frequency of the output current such that the output power is maximum; and inverter controller for controlling the inverter based on the determined current amplitude value and the determined frequency.

Abstract: A control system for a linear vibration motor capable of eliminating necessity of a separate sensor of detecting the motion of the motor. The linear vibration motor includes a stator provided with a winding, and a vibrator provided with a permanent magnet. The winding is fed with a drive current to generate a magnetic field which interacts with the permanent magnet to cause the vibrator to reciprocate linearly relative to the stator for producing a vibration. The control system includes a controller which detects an ongoing amplitude, i.e., the motion represented by the displacement, speed, or acceleration of the vibrator and provides ON-periods of feeding the driving current to the winding in a varying amount based upon the ongoing amplitude detected in order to keep a vibration amplitude of the vibrator constant.

Abstract: A scanner determines whether a target is a bar code symbol and, if so, whether that symbol is one-dimensional or two-dimensional. For two-dimensional symbols, the scanner aligns a scanning pattern with the symbol and expands the scanning pattern to reach only to the top and bottom edges of the symbol, not beyond. The scanner also has a microprocessor-control scanning engine that uses a coil to drive a scanning element and pick up feed back signals from the scanning element. A pulse-width-modulated regulator also provides fast and efficient operation for driving the coil. The scanning engine can also be designed to generate a pattern that precesses across the target, and a powerful interface to the scanning engine allows decoding and control logic to work efficiently with and independently of the scan engine.

Abstract: A yarn guide imparts a traversing motion to a yarn being delivered to a rotationally driven takeup bobbin in a textile yarn winding operation to create a cross-wound bobbin, or cheese. The yarn guide includes a fork-like yarn guide pivoted about a pivot axis substantially perpendicular to the axis of the takeup bobbin, and an electromagnetic mechanism for driving the guide. The electromagnetic mechanism includes an air gap, a plurality of magnets disposed along the air gap, a plurality of yokes and at least one electrical coil extending into and moveable along the air gap with the traversing yarn guide. The magnets are disposed along the air gap and generate magnetic field lines which extend in a substantially perpendicular direction through the air gap.

Abstract: A servo control system for a voice coil motor including a servo controller using position feedback to provide an acceleration current to the voice coil motor and voice coil brake providing a deceleration current based upon velocity feedback from the voice coil motor. In one embodiment, the velocity of the voice coil motor is derived from current feedback. A method for braking an actuator driven by a voice coil motor including the steps or receiving and processing current feedback from the voice coil motor and supplying a deceleration current to the voice coil motor derived from the current feedback from the voice coil motor.

Abstract: A method for driving a linear oscillating motor and a linear oscillating motor are provided. The motor includes a fixed magnetic member, a movable member having a magnet and being supported to oscillate relative to the fixed magnetic member, a detector that detects displacement of the movable member, and a control that oscillates the movable member by sending drive current to a coil of the fixed magnetic member. The method includes controlling, during a first half-period that occurs within a full amplitude period of the movable member, the drive current based upon the output of the detector. The method also includes controlling, during a second half-period that occurs within a fill amplitude period of the movable member, the drive current based upon a fixed drive current waveform.

Abstract: A system that extends the life of bearings that support a primary payload and operate in oscillatory mode. The system integrates the primary payload, a reaction mass and the bearings into a single support structure so that constant hydrodynamic lubrication of the bearings is achieved even during stopping and reversal of the primary payload. This is accomplished by allowing the bearings to rotate continuously in one direction while the primary payload is oscillated. Torque compensation may be provided by applying an opposite torque to the reaction mass to minimize the torque disturbance experienced by the support structure.

Abstract: A controller is provided to control and fix the stroke and frequency of the piston movement of the compressor under various operating conditions. The controller includes a signal generator for providing a first signal, a detector generating a second signal after detecting that the piston has a displacement, and a signal processing unit electrically connected to the signal generator and the detector for outputting a control signal to the compressor after receiving the first signal and the second signal to control a movement of the piston.

Abstract: The oscillating mechanical device comprises a shaft on which an oscillating member is mounted, and which is resiliently urged towards a middle angular equilibrium position, together with a single-phase induction motor whose rotor is coupled to the shaft so as to enable oscillations of the shaft to be sustained. According to the invention, the stator of the single-phase induction motor is fed with an alternating drive signal whose frequency is adjusted to the vicinity of the natural frequency of oscillation of the mechanical device. More particularly, the frequency of the drive signal of the stator is set to lie in the frequency range ?f-0.8 Hz; f+0.1 Hz!, where f represents the natural frequency of oscillation of the mechanical device, and is preferably set to the natural frequency of oscillation of the mechanical device with a tolerance of plus or minus one-tenth of one hertz. The device is applicable to card web combs used in the textile industry.

Abstract: Disclosed is an AC electric motor with oscillating rotary output, a permanent magnet rotor having radially magnetized magnets, and feedback control of oscillation amplitude. Amplitude control is accomplished without a separate amplitude sensor by using an accurate model of the motor as a basis for calculation of amplitude from measurements of motor voltage and current. The motor has high efficiency, low inertia, and uses a relatively small volume of permanent magnet per unit power output.

Abstract: A drive device for a vibration motor which provides constant efficient driving with a simple circuit and control sequence. The drive device for the vibration motor includes a charging circuit which impresses a predetermined voltage on an electromechanical energy conversion element, a discharge circuit which causes discharge of the electromechanical energy conversion element via an inductive element, a control circuit which alternately connects the charging circuit or the discharge circuit to the electromechanical energy conversion element, and a period detection circuit which detects the period of the resonant frequency of a circuit formed by the electromechanical energy conversion element and the inductive element.

Abstract: The present invention relates to a method for driving an ultrasonic motor of the type which includes a vibrator for causing a flexural vibration wave in response to a pair of AC driving voltage signals, and a rotor in contact with the vibrator and moved by the flexural vibration wave. The rotational speed of the ultrasonic motor is controlled by using a feedback signal and a data table, the feedback signal indicating the current rotational speed of the ultrasonic motor, and the data table storing values of the feedback signal as a standard function of the rotational 21 speed. The method includes the step of sampling the feedback signal and detecting the rotational speed in a plurality of rotation states of the ultrasonic motor. The method obtains an approximate function representing the relationship between the sampled feedback signal and the detected rotational speed of the ultrasonic motor, and calculates correction coefficients for adjusting the approximate function to the standard function.

Abstract: A control system for a scanning motor that may operate at constant power, which has a control circuit including an H-Bridge connected across the drive coil of the motor. The control circuit operates under microprocessor control for digitally generating selected high current and a low current thresholds, which can be changed to enable the scanning motor to be operative over a large range (e.g. 3.3 v to 8 v) of supply voltage and to control the arc over which the motor oscillates and, therefore, the scan angle of an optical beam which scans a bar code. The control circuit turns the current to the drive coil on and off when the high and low thresholds are reached thereby varying the current which the motor draws which determines the scan angle and scan rate and average current draw, which may be maintained constant for constant power consumption.

Abstract: A piece of furniture has a frame and a part capable of rocking on the frame at a natural rocking frequency. A drive has a sensor for detecting movement of the part on the frame, a drive motor connected between the frame and the part for rocking the part on the frame, and a controller connected between the drive and sensor for rocking the part on the frame at the natural rocking frequency up to a predetermined maximum angular displacement of the part on the frame. The sensor detects angular movement, that is angular speed, angular position, and/or angular acceleration of the part on the frame. The controller has a response field and operates the drive in accordance therewith.

Abstract: A magnetic bearing assembly is disclosed which provides for correction of shaft deflection, or "bowing", during rotation of the shaft. The assembly comprises two stator rings in spaced relation to each other, and each stator ring comprises a plurality of stator sections which are independently activated. When the shaft "bows", sensors detect the deflection and independently activate the various stator sections producing a force couple which acts on the rotor to produce a bending moment in the shaft which tends to counteract the "bowing".

Abstract: A single cycle positioning system utilizing a three phase wye connected induction motor (10) includes a three phase inverter (28) and a microprocessor (20) for controlling the inverter to generate three phases of power. Pulse width modulation techniques are utilized and in response to a start signal the frequency of the power to the motor is increased up to a running frequency, and in response to a stop signal the frequency of the power applied to the motor is decreased along with a corresponding reduction of the voltage applied to the motor.

Abstract: Drive system for a water pump unit (7, 8) driven by the shaft of a reversible motor (4) through a partition wall, about said shaft (5) being mounted a first sealing ring (14) fixed to said wall (13), and a second sealing ring (15) rotatably driven by the shaft and forming a rotatable water-tight sealing arrangement (6) with the first ring (14). The system includes control device (19, 22) capable of normally actuating the motor according to a preset program, and devices (19, 20, 26) to make the motor temporarily oscillate at a predetermined frequency (f), with a sequence of rotations in alternate directions, in case the two sealing rings (14, 15) are sticked together. The oscillation of the rotatable unit associated with the rotor (5) causes the two sealing rings to mutually separate.

Abstract: When a sewing machine is locked during stitching of a thick fabric, the rotational direction of a sewing motor is alternately reversed at a predetermined time interval. A needle operatively coupled to the sewing motor through a mechanical system is moved up and down, whereby the needle sticks into the same stitching point for a desired number of times.

Abstract: A card web comb driving system in machines for the textile industry comprng a comb structure (27) mounted in such a way as to oscillate around a resting position under the control of elastic means (23 and 24) which accumulate mechanical energy and are associated with electrical motor means (20) of the type in which the direction of rotation can be inverted with the variation of the electrical signal. The motor means (20) is associated with a sensor (31) of the instantaneous angular position of the shaft (30) of the motor (20) and consequently of the instantaneous angular position of the comb structure (23, 26 and 27). The sensor (31) is connected to the power supply (21) of the motor (20) in order to establish a persistent oscillatory condition on the movable element of the motor (22) and consequently on the comb structure. The motor (20) can be represented by a brushless type motor or by a direct current motor with a constant excitation field.

Abstract: A synchronized drive for a slide with a slip clutch which dissipates excess energy in an overload or crash situation to prevent damage to the mechanism. The slip clutch is coupled between a servo motor and a gear reducer to dissipate excessive force during a crash or an overload condition. A position feedback transducer is coupled to the gear reduced downstream of the clutch to maintain synchronization, even after a crash or overload condition, without requiring any re-homing sequence.

Abstract: A bidirectional variable reluctance linear actuator and force control system by which one or more bidirectional linear actuators can be operated to produce a linear relationship between the net force on the armature structure and an applied flux linkage variation signal, as well as an actuator system by which the transmission of vibration through a structure can be blocked by applying forces and/or moments to the structure so as to cancel out its vibratory velocity. An adaptive control system, which is synchronized to machine speed, is able to determine the proper forces that will cancel the vibration of the structure and automatically null out each harmonic of the structure vibration, and cancels the vibration in up to six degrees of freedom of structural motion. The system can provide active attenuation system with a variety of noise sources and transmission paths, i.e.

Abstract: A cyclically varied magnetic field extending from a pole piece interacts with the repelling field of a superconductive member while conducting electrical current therethrough to generate a force transmitted to a frame which mounts the pole piece and the superconductive member in spaced relationship to each other forming a flux gap therebetween within which the magnetic fields interact. A power control unit regulates the variation of the magnetic field by means of an electromagnetic assembly mounted on the pole piece and controls cyclic interruption of current through the superconductive member.

Abstract: The present invention provides an apparatus including a laser scanner wherein the apparatus further includes a scanner temperature detector (3) located in the proximity of a position sensor (2), an environment temperature detector (4) and temperature controlling mechanism adapted to perform controlling operation so as to allow the temperature of the position sensor to be kept constant on the basis of an output from the environment temperature detector and an output from the scanner temperature detector.

Abstract: Controlled movement of a motor driven pressure modulator is provided by commanding maximum current to the motor by application of system voltage resulting in the motor current initially rising rapidly to the motor stall current. The motor accelerates at a rate that is a function of the difference between the motor torque and the load torque represented by the load on the modulator. As the motor speed increases, the motor current decreases. When the motor current decreases below the stall current by a predetermined amount representing a predetermined speed of the motor, the motor current is turned off for a wait period that is based upon the time that it took for the motor speed to attain the predetermined speed. Thereafter, maximum motor current is again commanded and the cycle repeated to provide for motor speed control.

Abstract: In a grinder having a reciprocating table, a pair of oppositely arranged traverse potentiometers are actuated by the table, and in each direction, the respective potentiometer produces an increasing voltage to reverse the table. A pair of remote potentiometers are arranged respectively opposed to the traverse potentiometers, and are manually set to thereby determine the points of reversing of the table. Signal LED's indicate the position of the table, and these are controlled by signal potentiometer that is driven with the traverse potentiometers. Manual switch means enables the operator to selectively run the table past the normal points of reversal set by the remote potentiometers. Means is provided for slowing the speed of movement of the table at the end of its travel to minimize inertial shock.

Abstract: A resonant scanner has at least one torsionally rigid damper located at at least one torsional node point of a torsion bar. At least one node of an unwanted vibrational mode is determined to be at a distinct node point, whereby the damper damps the unwanted vibrations while passing desired torsional oscillations. The damper serves as the only physical coupling of the torsion bar to the housing and damps transmission of vibrations into and out of the scanner. One or both ends of the torsion bar may be configured as the rotor of a motor. The rotor fits within but is not physically coupled to a bobbin coupled to the frame. Two coils are wound on the bobbin at approximate right angles to each other to minimize a cross-coupling between the coils.

Abstract: The electrical termination impedance of a variable reluctance electro-mechanical transducer is changed automatically in response to the frequency of vibration applied to the transducer to provide the optimum electrical termination impedance which produces the highest effective mechanical impedance at said frequency. The transducer includes magnetic cores interconnected by a spring formed by cutting a relatively thin medial annulus in a relatively thick flat disk. A digital logic circuit uses a signal counter and NAND gates to determine the frequency and close the appropriate fast-acting relay in a parallel array of capacitor-relays. A negative-impedance electrical termination provides a high mechanical impedance over a broad band of frequencies. A shunting circuit eliminates spurious resonances by providing substantially no shunting in the transducer terminating circuit at resonant frequency and substantial shunting in the terminating circuit at other frequencies.

Abstract: Mechanical resonance of the vibratory feeder is maintained by minimizing a phase angle difference between substantially sinusoidal drive voltage and current wave forms. The mass flow rate of material being fed is controlled by controlling the electrical power applied to the vibratory feeder compared with a desired electrical power computed from a desired flow rate. The preferred embodiment includes synthesized drive wave forms which are variable in frequency and amplitude in order to maintain the vibratory feeder in mechanical resonance at the desired flow rate. Resonant operation and accurate material flow are accomplished without use of electromechanical vibration sensors and control is accomplished using the magnitude and phase relationships between the applied voltage and current drive wave forms.

Abstract: An electromagnetic fluid pump having a magnet attached to a reciprocating piston and a hall effect switch detecting the magnetic field generated by the moving magnet. In a first position of the magnet, the magnetic field through the hall effect switch is in a first direction causing the hall effect switch to generate a signal having a first polarity. In a second position of the magnet the magnetic field through the hall effect switch is reversed, reversing the polarity of the signal generated by the hall effect switch. An electronic switch circuit responsive to the signal generated by the hall effect having the first polarity to energize the solenoid coil to retract the piston from the first position to the second position against the force of a spring and further responsive to the signal having a reversed polarity to deenergize the solenoid coil when the piston is in the second position.

Abstract: Device for fatigue-testing a mechanical component by exciting this component (1), to which massive armatures (2, 3) may be attached, using an electromagnetic vibrator (13) fed by a generator, characterized in that the said generator comprises a displacement sensor (14) placed between two parts of a vibrating assembly (1, 2, 3) and generating a sinusoidal signal; a root-mean-square value converter (5) converting this alternating signal into a direct current signal of root-mean-square value; and an analog divider circuit (7) receiving the sinusoidal signal as numerator (8) and the root-mean-square value signal produced by the said converter as denominator (6), with the output signal (9) from this divider (7) being used after amplification (12) to drive the electromagnetic vibrator (13) acting on the vibrating assembly.

Abstract: A control arrangement for vibratory conveyors, including bowl and linear types, in which the vibration frequency is set by the behavior of the conveyor and not by an applied frequency. A sensor, SC, senses the behavior of the conveyor and a frequency, of controlled amplitude and phase, is derived from the sensor output to energize conveyor drive means, AV and AH1 to AH3. User controls (HA, VA, PA) for amplitude and phase can be mark/space adjusters (HMS, VMS, DMS) effective on the base circuits of transistors connected to electromagnetic actuators. Low voltage operation (less than 50v) is provided without proportionally increased current, partly by energy recovery from the inductors in the actuators. Two levels of protection against supply ripple are included (RT, RLA) and the actuator drive can be stabilized against supply variation (MSC). The low-voltage operation provided is both safer and more efficient than mains voltage operation.

Abstract: A drive circuit (10) for driving an actuator/mass (A) at its natural resonance and for maintaining the instantaneous output signal of the mass at a predetermined constant value over a wide range of dynamically changing resonant frequencies, is disclosed. Current sensing circuitry (C) detects an instantanous current passing through the actuator/mass (A). A compensation circuit (D) modifies the instantaneous sensed circuit signal to compensate for dynamically changing physical parameters of the actuator mass and for phase irregularities introduced into the sensed signal when the mass oscillates near its natural resonance. Automatic gain control circuitry (E) alters the actuator drive signal to maintain amplitude of the mass oscillation at a predetermined constant value. A drive circuit (B) performs the actual drive function in response to the feedback signal received from the automatic gain control and compensation circuitry.

Abstract: A well pump control system is disclosed for utilization with a conventional well pump having a stationary member and a reciprocating member. The reciprocating member operates a down-hole pump and is attached to a rocking beam. The rocking beam is driven by an electric motor through a counterbalanced crank. The position of the counterbalanced crank and the speed of the electric motor are utilized to operate a reduced voltage starter which acts to control the voltage applied to the electric motor. In this manner, voltage may be selectively and gradually applied to and removed from the electric motor at selected points during the pump cycle to both minimize power consumption and increase slip during heavy loading, by allowing the momentum of the crank to operate the reciprocating member during at least a portion of each cycle of the pump.

Abstract: A two-directional percussion implement selectively adaptable both for driving in and for extracting, e.g. piles, from the ground, includes two coaxial electromagnetic coils whose movable armatures are represented by extremities of a reciprocable ram. Opposite anvils, one of which is adapted to be coupled with a driven element, are interlinked by a non-magnetic shaft traversing the ram. When the implement is intended for drilling operations, a rotary drive imparts rotation to one of the anvils via a connection permitting independent rotation and reciprocation. The shaft in this case has a central channel for taking samples or for conducting drilling fluids. When adapted only for axial percussions, the implement is vertically suspended on a cable via a shock absorber.

Abstract: A control arrangement for vibratory conveyors, including bowl and linear types, in which the vibration frequency is set by the behavior of the conveyor and not by an applied frequency. A sensor, SC, senses the behavior of the conveyor and a frequency, of controlled amplitude and phase, is derived from the sensor output to energize conveyor drive means, AV and AH1 to AH3. User controls (HA, VA, PA) for amplitude and phase can be mark/space adjusters (HMS, VMS, DMS) effective on the base circuits of transistors connected to electromagnetic actuators. Low voltage operation (less than 50v) is provided without proportionally increased current, partly by energy recovery from the inductors in the actuators. Two levels of protection against supply ripple are included (RT, RLA) and the actuator drive can be stabilized against supply variation (MSC). The low-voltage operation provided is both safer and more efficient than mains voltage operation.

Abstract: An electromagnetic fluid pump having a magnet attached to a reciprocating piston and a Hall effect switch detecting the magnetic field generated by the moving magnet. In a first position of the magnet, the magnetic field through the hall effect switch is in a first direction causing the hall effect switch to generate a signal having a first polarity. In a second position of the magnet the magnetic field through the hall effect switch is reversed, reversing the polarity of the signal generated by the hall effect switch. An electronic switch circuit responsive to the signal generated by the hall effect having the first polarity to energize the solenoid coil to retract the piston from the first position to the second position against the force of a spring and further responsive to the signal having a reversed polarity to deenergize the solenoid coil when the piston is in said second position.

Abstract: A control system is disclosed for use with a device, such as a vibratory bowl feeder, having a bowl or other member mounted for vibratory motion and including an electromagnetic driver for vibratorily driving the part. The control system includes a detector for detecting the vibratory frequency of the part, which tends to vibrate at its resonant frequency, and causes energizing pulses of power to be supplied to the driver supplied at a frequency equal to the detected frequency. Thus, the driving frequency is made equal to the resonant frequency and follows changes in such frequency to obtain maximum performance. The power to the drivers is also switched so that during alternate pulses the current flows through the driver coil in opposite directions to inhibit buildup of residual magnetism in the coil core. The control system uses a phase-locked loop circuit and other parts comprised of components most of which are available as standard integrated circuits.

Abstract: An oscillating-armature electric motor comprises an armature which, during operation of the motor, moves along a path of oscillatory movement that includes a substantial range of movement in which the armature poles are located remote from the stator poles. When the poles are remote from each other, the efficiency of electrical to mechanical energy conversion would be low. The stator winding is energized in dependence upon the position of the motor, to avoid wasteful electrical energy dissipation during that part of the armature swing in which the aforementioned efficiency would be low. During the part of the armature swing in which the efficiency is high, the energization is great enough to establish a range of armature movement which goes beyond the high-efficiency armature positions to predominantly comprise low-efficiency armature positions.

Abstract: Converters are known where input pulses are coupled to a detector stage via an adding device and a first integrating register. The detector stage provides an output signal relative to threshold values which increases, keep constant or reduce the contents of a second integrating register. The contents of the second register are coupled to the minus input of the adding device. The time variation of the input pulses may be coupled from the detector stage. According to the present invention the dynamic behavior, stability and suppression of disturbances is improved by differentiating the input pulse train, coupling this pulse train to the detector stage and to integrate the output of the detector stage with the integration factor being constantly adjusted to the output signal of the detector stage.

Abstract: An optical scanning device has a mirror for light scanning, a motor composed of an armature and a stator, a case for supporting said stator of the motor, a torsion rod for generating a restituting force against the driving force of said motor to limit the rotating angle of said armature, and a speed detecting element. Said torsion rod is fixedly supported at one end thereof by said case and rotatably supported at the other end thereof by a bearing member. Said mirror, said armature and said speed detecting element are provided between both the supported ends of said torsion rod.