Abstract: An electromagnetic propulsion system is provided. The system comprises first and second pluralities of stator coils wound about first and second axes, a plurality of support structures, first and second couplers that surround portions of the first and second pluralities of stator coils, and first and second pluralities of sets of rotor coils wound about axes that are parallel to the first and second axes. The stator coils are configured to receive electric current through an outside controller selecting appropriately coupled stator sections or through a sliding electrical contact system or bearing system to induce at least a first magnetic field. The plurality of support structures supports the first and second plurality of stator coils. The first and second couplers include notches and are oriented so that their notches pass over the plurality of support structures when the couplers move along the stator coils. The couplers may have an adjustable segment to close the notch.

Abstract: A level sensor, particularly an electromagnetic pushing and knocking-type object detector, comprising: a magnetic swinging rod, an electromagnet that is disposed on one side of the magnetic swinging rod, and an electronic module that controls the electromagnet in driving the magnetic swinging rod to swing, and amplifies, processes, and time-delay outputs the swinging signals of the magnetic swinging rod, which swinging signals are collected by the electromagnet, said magnetic swinging rod is suspended with a suspension device on one side of a main housing, and the electromagnet, which is composed of an electromagnet iron core and an electromagnet coil, is disposed inside the main housing.

Abstract: A power converter includes a first electric power conversion unit having an inverter for converting a first DC electric power to an AC electric power, an AC circuit connected to the first electric power conversion means; a second electric power conversion unit for receiving the first DC electric power and converting the same to a second DC electric power having a voltage level that differs from the voltage level of the first DC electric power, a power storage unit for storing the second DC electric power of the second electric power conversion unit; and a ripple suppressor having a first inductance for guiding the second DC electric power of the second electric power conversion unit to the power storage means and a second inductance for suppressing the ripple component included in the second DC electric power arranged between the second electric power conversion unit and the power storage unit.

Abstract: A linear actuator driving device is provided. The linear actuator driving device includes an electromagnetic driving unit which makes a moving element reciprocate in response to a driving command and an offset correcting unit which corrects the driving command to carry out offset energization to make the center of reciprocation of the moving element be moved in the direction in which deviation between the center of reciprocation of the moving element and the center of the movement possible range is eliminated. The offset correcting unit is configured such that the amplitude information is acquired and, with respect to the amplitude value corresponding to the acquired amplitude information, if the movable amplitude is in a movable area insufficient condition, correction of the driving command is performed and, on the other hand, if the movable amplitude is not in the movable area insufficient condition, correction of the driving command is released.

Abstract: A power conversion apparatus includes: a line breaker that is connected in series to a direct-current power supply; a first capacitor that is connected in parallel to the direct-current power supply through the line breaker; a discharge circuit that includes a resistor and a first switching circuit connected in series and is connected in parallel to the first capacitor; a power converter for driving a synchronous machine; a second capacitor that is connected in parallel to a direct-current side of the power converter; a second switching circuit that is connected in series between the first capacitor and the second capacitor; and a control circuit for controlling the discharge circuit. The control circuit controls the discharge circuit on the basis of the voltage of the first capacitor and the voltage of the second capacitor.

Abstract: An embodiment of an electric motor car control system includes a resistor connected parallel to a main motor cut-off switch, or a switch for grounding terminals of the main motor, to discharge electric charges accumulated in stray capacitances of the main motor, whereby the electric motor car control system can prevent electrical shocks due to electric charges accumulated in main motor stray capacitances.

Abstract: A method for driving a Linear Resonant Actuator (LRA) is provided. During a first off interval, the back-emf of the LRA is measured. During a first off interval, a timer is started when the back-emf reaches a predetermined threshold, and after a predetermined delay has lapsed following the back-emf reaching the predetermined threshold during the first off interval, the LRA is driven over a drive interval having a length and drive strength. A second off interval is entered following the drive interval, and during the second off interval, the back-emf of the LRA is measured. During the second off interval, the timer is stopped when the back-emf reaches the predetermined threshold. The value from the timer that corresponds to the duration between the back-emf reaching the predetermined threshold during the first off interval and the back-emf reaching the predetermined threshold during the second off interval determines the length.

Abstract: Systems and methods for controlling an inertia of a synchronous condenser are described. An example system may include a motor, bidirectional power source, and at least one control device. The motor may be configured to alter a rotation of a condenser shaft to obtain a desired inertia of a synchronous condenser during a power disturbance event. The bidirectional power source may be coupled to the motor. The at least one control device may be configured to identify the power disturbance event, determine an amount of power to supply to or receive from the motor to obtain the desired inertia, and control the supply of power from the power source to the motor or from the motor to the power source based upon the determined amount of power.

Abstract: A phase change pulse engine includes a superconducting magnet and a control circuit including a power supply and a capacitor. A changing magnetic field creates a magnetic coupling for a mechanical drive. The capacitor is connected to the power supply and the magnet's coil through a switching and timing control circuit to initially charge the capacitor. With the coil isolated from the capacitor, electric current from the capacitor is discharged through the coil to create the magnetic coupling. After a predetermined period of time, an electrical connection is re-established between the capacitor and the coil to recharge the capacitor. This generates a pulse of electrical energy that is periodically applied to the coil with the capacitor isolated from the coil. The pulse of electrical energy includes make up energy due to capacitor losses.

Abstract: A vibration generator has an oscillator including a magnet and a holding member for holding the oscillator based on a magnetic force emitted from the oscillator. The holding member includes a magnet or a magnetic body. The oscillator vibrates relative to the holding member. A magnetic force between the oscillator and the holding member defines a natural period of vibration of the oscillator relative to the holding member. When a periodic current is supplied to an electromagnetic coil fixed to the holding member, the oscillator vibrates relative to the holding member so as to synchronize with the period of the periodic current. By synchronizing the period of the periodic current with a natural period, the oscillator resonates.

Abstract: The adapting system for a resonant drive appliance includes a circuit for measuring the back EMF induced in the stator coil of the motor following turn-off of the appliance. The frequency of the back EMF signal is determined from the zero crossings of the EMF signal. The determined frequency is then compared with a running average of previous frequency determinations, and the drive frequency of the appliance is adjusted if the difference between the compared frequencies is greater than a threshold value, e.g. 1 Hz.

Abstract: The present invention discloses a control apparatus for a linear compressor which can vary a cooling force and prevent an inrush current. The control apparatus for the linear compressor includes a coil winding body laminated on the linear compressor, a first capacitor connected in series to the coil winding body, a capacitance varying unit being formed in a parallel structure to the first capacitor, and having a capacitor switch, and a control unit for inducing an output change of the linear compressor, by varying the whole capacitance of the control apparatus by controlling the capacitor switch.

Abstract: A pumping driver for a linear motor, which includes a DC/DC converter that performs the function of constant power pumping or constant input current pumping of a battery to a linear motor.

Abstract: A vibration generator has an oscillator including a magnet and a holding member for holding the oscillator based on a magnetic force emitted from the oscillator. The holding member includes a magnet or a magnetic body. The oscillator vibrates relative to the holding member. A magnetic force between the oscillator and the holding member defines a natural period of vibration of the oscillator relative to the holding member. When a periodic current is supplied to an electromagnetic coil fixed to the holding member, the oscillator vibrates relative to the holding member so as to synchronize with the period of the periodic current. By synchronizing the period of the periodic current with a natural period, the oscillator resonates.

Abstract: A capacitor, inductor, and power line are arranged in a series parallel combination tank circuit that operates over four quarters of a complete cycle. During the first quarter cycle: power is applied to the tank circuit, current flows through the inductor to the capacitor, current is stored in the inductor, and the capacitor is charged. During the second quarter cycle; current is released from the inductor as the capacitor discharges current to another parallel inductor or resistive load. During a third quarter cycle: current flows in the capacitor from the opposite direction, the capacitor is charged, current pushes out from the capacitor to the incoming power line, and current is stored in the inductor. During the fourth quarter cycle: the capacitor discharges in the opposite direction, current parallel to another inductor or resistive load flows in the opposite direction, and the inductor releases current to incoming power line.

Abstract: Reversible motor including a stator having two windings (a–a?, b–b?), a start apparatus (c–c?) connected to one of the two windings (a–a?, b–b?) in series, switches (310,330,350) for providing power to the two windings selectively, wherein the switches, for reversing the motor, are connected selectively such that the direction of the current in the one of the two windings is reversed and the start apparatus is connected to the other one of the two windings in series, and a turns ratio and a cross section area ratio of the two windings being adjusted for a sufficient start torque and an optimal efficiency of the reversible motor.

Abstract: A vibration motor obtains a FAST signal when r.p.m. of the motor is faster than reference speed, whereby an output-driving circuit is controlled by the FAST signal to omit parts of the powering periods of respective phases. The motor thus controls the r.p.m. and increases torque ripple generated from the motor. As a result, vibration magnitude increases and insufficient vibration due to downsizing of the motor can be compensated by the control system.

Abstract: A dual sided self-oscillation circuit for driving an oscillatory actuator with high efficiency and high response speed. The actuator has a winding to receive a periodical supply current from a power source and oscillates in a predetermined resonant frequency. The self-oscillation circuit includes a bandpass filter for receiving a back electromotive force voltage (Vbemf) developed across the winding and producing a sine wave output signal, a comparator for comparing the sine wave output signal with a threshold voltage and producing two drive pulses per cycle of the resonant frequency, and a switch connected in series with the winding to connect or disconnect the power source to the winding in response to the drive pulses, thereby flowing electric current in two directions at each cycle.

Abstract: An actuator driving circuit is provided for a positive feedback amplification, through an amplifier, of a counter electromotive force generated in a stator coil of a linear actuator, for continuating a reciprocating movement of a moving element by self-oscillation of the linear actuator, and for an application of a periodic voltage to the stator coil, while the voltage is made sinusoidal if required, so as to render the driving circuit to be high in the driving efficiency and small in dimensions.

Abstract: A self-starting swinging apparatus including a free-running oscillation circuit comprising two transistors which are a PNP transistor and an NPN transistor, the bases of both transistors being connected respectively to the collector of one transistor directly and to the collector of the other transistor through a capacitor for setting a time constant; a driving coil connected to the collector of the transistor with the capacitor connected thereto, as a load on the transistor; and a permanent magnet having a relatively repulsive magnetic pole arrangement of the same polarity as, or having a relatively attractive magnetic pole arrangement of a different polarity from, that of a magnetic pole in a magnetic field which ought to be generated in the driving coil when an electric current is fed to the driving coil from the oscillation circuit, the permanent magnet being relatively movable with respect to the driving coil and capable of performing a relative swing motion under the action of an arbitrary restoring for

Abstract: A drive circuit including a power stage [PSH/PSV] and a control stage therefor to co-operate to supply energy in a controlled manner with regard to a reference value to an inductive load when connected in operation, means [R21, R41/R25, R42] in the power stage to produce a lower level signal indicative of the energization of the load, means [HPR/VPR] to generate a reference value for the energization signal representing a required energization, means [U3.3/U3.4] to compare the energization signal and the reference value and generate an error signal representing any difference therebetween and means [U2.1/U2.3, U2.4] to apply said error signal to said control stage to alter the energy supplied to the load towards the required condition, the reference value may also be related to the frequency at which the load is energized (SE, FBF, OSC, D4).

Abstract: DC power is supplied to an induction motor for a compressor by switching ON/OFF in response to a modulated voltage waveform obtained from modulating waves which are used for generating AC power for energizing an induction motor and a carrier wave according to PWM theory. The compressor has a compressing element rotated by the induction motor, and the modulating wave is corrected according to a rotational angle of the compressing element. A sine wave having the same frequency as the modulating wave is added to the modulating wave, and a phase of the sine wave is controlled so that a maximum value of the sine wave corresponds to the compression stage of the compressing element. Thus, a rotation speed of the compressing element is constant in a suction stage and a compression stage.

Abstract: The apparatus includes a driver (86). The driver (86) includes a front portion (90) which is adapted to receive a riveting die (92), and a rear portion (88) which is a copper plate. The copper plate (88) is receptive to the establishment of magnetic field currents therein. The actuator further includes a coil (72) which is positionable in close proximity to the copper plate (88) of the driver (86). The apparatus further includes a bank of capacitors having a stored charge so as to produce a current pulse through the coil (72) when the capacitors are connected to the coil (72). Still further, the apparatus includes a control means for selectively connecting the stored charge from the capacitors to the coil. The copper plate (88) is relatively thick compared to that used in high voltage electromagnetic actuators, such that the present apparatus requires only a relatively low voltage in order to produce the required high forces to accomplish the desired riveting.

Abstract: The AC/DC changeover device automatically changes from AC to DC current by setting a TRIAC on or off, to supply DC from a battery in the absence of AC, for powering an air pump for an aquarium.

Abstract: The apparatus includes a driver (86). The driver (86) includes a front portion (90) which is adapted to receive a riveting die (92), and a rear portion (88) which is a copper plate. The copper plate (88) is receptive to the establishment of magnetic field currents therein. The actuator further includes a coil (72) which is positionable in close proximity to the copper plate (88) of the drive (86). The apparatus further includes a bank of capacitors having a stored charge so as to produce a current pulse through the coil (72) when the capacitors are connected to the coil (72). Still further, the apparatus includes a control means for selectively connecting the stored charge from the capacitors to the coil. The copper plate (88) is relatively thick compared to that used in high voltage electromagnetic actuators, such that the present apparatus requires only a relatively low voltage in order to produce the required high forces to accomplish the desired riveting.

Abstract: An air pump for an aquarium includes a power source, first and second electromagnetic coils, and a circuit powered by the power source and coupled to the coils for energizing the coils in an alternating manner at a selected frequency, the circuit including an arrangement for varying the selected frequency. The air pump also includes a mechanical pump mechanism having two magnets which are each movably supported near a respective one of the coils and move in response to energization of the coils, and a pump arrangement which is responsive to movement of the magnets for effecting flow of a fluid.

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 method of and apparatus for measuring the vibration amplitude of an electromagnetic vibratory motor is disclosed in which the current induced in the coils of the motor is rectified and sensed and applied to a current signal conditioning circuit to produce an average current signal. The voltage across the coils is sensed and is applied to a voltage signal conditioning circuit to produce a peak voltage signal. First and second predetermined scale factor signals are generated. The average current signal is divided by the peak voltage signal and the result is multiplied by the second scale factor signal. The scaled divided signal is subtracted from the first scale factor signal to yield the desired signal representative of the vibration amplitude of the vibratory motor.

Abstract: An electro-magnetic device for an aeration pump for use in a fish tank or the like. The device includes a switch permitting the device to be operated with AC power, or with DC power and further, it can be operated with 120 V. or 240 V. AC. Upon being energized, the device will vibrate a vibrator member of a pump and the vibration strength can be varied with variable resistor.

Abstract: A variable-frequency feeder control using a single oscillator to develop signals for moving materials in either one of two directions. An output signal from the oscillator is applied to a first timing circuit which develops signal pulses for driving a horizontal electromagnetic drive coil. The first timing circuit controls the duration of the signal pulses which determine the amplitude of power to drive the horizontal coil. The output signal from the oscillator is applied to a second timing circuit which developes a phase shifted signal to control the phase between the power applied to the horizontal coil and the power applied to a vertical drive coil. A third timing circuit uses the phase shifted signal to develop signal pulses for driving the vertical coil and controls the duration of the drive pulses.

Abstract: An electromagnet hammer of the type described in U.S. Pat. No. 4,215,297 is autosynchronized by triggering the discharge thyristor in response to the detection of the position of the armature by a proximity detector, or by direct detection of the zero passage of the negative amplitude of the discharge current, or at a reference point representing the position of the armature, with a delay equal to at least half the period of the natural period of oscillation of the armature/plunger and its elastic suspension.

Abstract: A subharmonic controller for a dual coil electromagnetic vibrator, which derives both power and timing from a conventional a.c. line, having a zero crossing detector providing pulses at twice line frequency to a phase control. The phase control provides a selectively variable pulse width and triggers a frequency divider, which in turn triggers a divide-by-two-counter. Pulses from each of the phase control, divider and counter are fed to a logic controller which generates plus and minus gate signals. The gate signals alternately fire a pair of oppositely-directed SCR's, each SCR connected in series with one of the dual coils across the a.c. line. A polarity detector and reset circuit restore the polarity information and synchronize it with the direction of conduction of the SCR's.

Abstract: A vibrator control circuit is provided for controlling the driving current supplied to the driving coil of an electromagnetic vibrator for a bed or the like. The control circuit is adapted to be connected to source of A.C. line voltage such as a standard wall outlet and controls the duration of the portion of each cycle of the A.C. line voltage supplied to the vibrator. The control circuit includes an electronic switch, e.g., a transistor, connected in series with the driving coil of the vibrator and a control pulse generator for supplying control pulses to the electronic switch to control switching of the electronic switch in timed relationship with respect to the A.C. line voltage waveform so as to gradually vary the duration of the portion of the A.C. line voltage supplied to the electromagnetic vibrator during each cycle of the A.C. line voltage.

Abstract: A vibratory massage apparatus comprises a treatment portion elastically carried on a support, a vibration generator including an electric motor for providing vibrations to the treatment portion, and a control circuit connected to the motor for causing vibratory amplitude of the motor to be varied, whereby a variety of vibratory stimulation can be imparted to the user's affected part placed on the treatment portion of the apparatus with an excellent massaging effect.

Abstract: A synchronized subharmonic controller for a dual coil electromagnetic vibrator, which derives both power and timing from a single phase AC line, having a trigger circuit which operates the coils at one-third the power line frequency. A timing circuit is optically coupled to alternately fire a pair of oppositely-directed SCR's with each SCR connecting one of the coils across the AC line. The optical coupling reduces feedback from the coil circuitry to the timing circuit. A pair of capacitors supply additional power to operate the coils and to reduce the peak values of current supplied by the power line.

Abstract: A vibratory amplitude controller for vibratory mechanisms such as a vibratory feeder having in addition to a parts container, an electromagnetic drive unit operated from an A.C. current source for imparting oscillatory motion to the parts container. The controller includes a sensing means for sampling the electromagnetic drive unit current during a specific predetermined interval each A.C. current cycle to produce a vibratory amplitude representing signal. Means responsive to the vibratory amplitude representing signal controls the amount of power delivered from the A.C. current source to the electromagnetic dive unit to maintain a desired vibratory amplitude under varying load and A.C. line voltage conditions.

Abstract: A low cost electromagnetic fluid pump having molded structural plastic housing components, a biased reciprocating hollow piston, and a pair of plastic flapper valves providing for a unidirectional fluid flow is disclosed. An integrated circuit timer periodically energizes a solenoid coil producing an oscillating magnetic field reciprocating the piston.

Abstract: The invention relates to an electrically driven oscillating compressor, in particular for use as refrigerating machine, comprising a piston compressor, an electric oscillating drive for directly driving the piston compressor and a pulse shaper for supplying energy to the electric oscillating drive, wherein the group consisting of the compressor piston which is resiliently held in a central initial position, the other oscillating masses, the gas spring rate and the electric components of the oscillating drive form an electro-mechanical oscillating system whose natural frequency is at least approximately equal to the frequency of the current energizing the oscillating drive.

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 blocking oscillator for a reciprocating electromagnetic actuator having a solenoid coil, a detection coil for generating a control signal in response to a charge in the magnetic field generated by the solenoid coil, a silicon Darlington amplifier responsive to the control signal to control the current through said solenoid coil, and a diode connected in series with the collector of the Darlington amplifier rendering the Darlington amplifier immune to reverse voltage and transient signals.

Abstract: A vibrating armature motor, which includes a voltage source, an armature, an electromagnet having at least one exciter coil disposed adjacent the armature, a spring for rotationally biasing the armature, a sensor element for sensing the rotational velocity of the armature and for generating a signal proportional to the sensed velocity, a variable duty cycle pulse generator for generating a stream of triggering pulses, the duty cycle of the triggering pulses being dependent upon the sensor signal, and an electronic switch for controlling the current flow from the voltage source through the exciter coil in response to the triggering pulses.

Abstract: Circuitry is disclosed for driving the transducer assembly of a dental handpiece at its resonant frequency. The circuitry includes a variable frequency oscillator and a peak-detecting processor which allows the oscillator to sweep through a continuum of frequencies until maximum current in the transducer driving coil is sensed.

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: A vibrator mechanism, including a transducer and driving circuit, particularly adapted to vibrating a waterbed, includes two independently controlled vibration sources, each of which can generate vibration of varying amplitude and frequency. These two sources are typically mounted at opposite ends of a waterbed frame and vibrated at different frequencies so that interference waves may be produced within the water of the bed to produce a pleasing effect for the user. Additional circuitry is described which provides a time varying frequency and amplitude for each of the vibrators, and this circuitry is in turn controlled by a clock circuit so that, by using the time varying frequency and amplitude, the user may be slowly lulled to sleep or slowly awakened using the vibration within the waterbed as a stimulus for controlling the rate of falling asleep and waking up.

Abstract: A vibrator mechanism, including a transducer and driving circuit, particularly adapted to vibrating a waterbed, includes two independently controlled vibration sources, each of which can generate vibration of varying amplitude and frequency. These two sources are typically mounted at opposite ends of a waterbed frame and vibrated at different frequencies so that interference waves may be produced within the water of the bed to produce a pleasing effect for the user. Additional circuitry is described which provides a time varying frequency and amplitude for each of the vibrators, and this circuitry is in turn controlled by a clock circuit so that, by using the time varying frequency and amplitude, the user may be slowly lulled to sleep or slowly awakened using the vibration within the waterbed as a stimulus for controlling the rate of falling asleep and waking up.

Abstract: A material dispensing apparatus including drive structure for driving a feeder bowl is disclosed. A control circuit for controlling the drive includes a Hall effect amplitude sensing transducer for monitoring the magnitude of bowl vibrations and a braking circuit for controlling the damping of vibratory motion after the requisite amount of material has been fed from the feeder bowl. The braking circuit selectively reverses the current flow through a drive coil which comprises a portion of the drive circuitry of the apparatus. This current reversal disrupts the rhythm of forced oscillations which feed material from the bowl and causes bowl motion to be damped. A mechanical brake coupled to the bowl complements the braking action of braking circuit and locks the bowl in place to prevent accidental dispensing of parts.

Abstract: A circuit for controlling the intermittent application of a dc potential to a device, such as a striker mechanism for a gong, having a member reciprocally moveable between rest and active positions. The reciprocating member shunts and unshunts a capacitor when the member is in its rest position and moved away therefrom, respectively. While the capacitor is shorted, and during its charge time, dc power is applied to the device. When the capacitor is charged to a predetermined potential, dc power is disconnected from the device thereby allowing the reciprocating member to return to its rest position to shunt the capacitor and initiate a new cycle of operation. The system is substantially independent of mechanical characteristics of the device and the current interrupted or made by the contact pair may be at least an order of magnitude less than the peak current in said device.

Abstract: A control circuit for an electromagnetic cutting apparatus includes auxiliary power impulse systems and auxiliary condensers for accelerating an already moving plunger of the cutting apparatus. The basic control circuit includes photoelectric sensors for sensing the leading and trailing edges of components. The sensors are part of an electronic circuit for rapidly charging a coil surrounding a core on the plunger for driving a blade downwardly to cut the tape. Condensers in the electronic circuit are normally charged and, in response to signals from the photoelectric sensors, instantaneously discharge into the coil to actuate the plunger. The auxiliary power impulse systems and auxiliary condensers are controlled by timers for discharging the auxiliary condensers into the coil a short time after the condensers of the basic circuit and while the plunger is moving to accelerate the latter.

Abstract: An electromagnetic hammer has a coil coacting with an axially reciprocable armature including a ferromagnetic core traversed by an elongate nonmagnetic ram which carries at one end a spring-loaded piston head forming part of a pneumatic damping device, its other end co-operating with a working tool. The coil is intermittently energizable by a control system including a capacitor chargeable from an electric power supply by way of a first thyristor and dischargeable through the coil by way of a second thyristor, the two thyristors being sequentially triggered in response to a control pulse applied to a transformer with two secondaries generating staggered firing pulses with the aid of a delay network in the output circuit of one of these secondaries.

Abstract: A switch control system particularly well suited for use in a electromechanical vibrator drive. Solid-state switches and diodes are used in combination with a DC power supply to alternately switch energy between the electric field of the power supply filter capacitor and the magnetic field of the actuator coil of a vibrator in a power resonant mode. The control system includes a variable frequency oscillator and a controllable pulse generator which respectively provide signals for controlling the closing and opening of the switches whereby the frequency and amplitude of movement of a vibratory feeder may be adjusted.