Abstract: A drive control system for a linear motor having a stator and a sliding member capable of sliding along the stator. A position detector comprises an arrangement of light emitting elements and a detector, or the converse to produce a position signal. A comparator compares the position signal with a reference signal to produce an output drive signal for the linear motor.

Abstract: A novel linear motor making use of a D.C.

Abstract: In order to correct non-linearities inherently existing in the relation between the value of a hydraulic fluid parameter controlled by a proportional valve and an operating signal controlling the valve, in an arrangement in which the setting of the valve is controlled by effecting a comparison between the operating signal and a feedback signal representing the valve movement, a memory is provided to modify one of those signals prior to comparison in a manner to compensate for such non-linearities.

Abstract: There is disclosed a device for displacing a video disk with respect to a reading head which includes the driving of a conductive disk by means of a video disk rotational motor. The conductive disk passes through the air gaps of two electromagnets located on either side of the displacement axis of a movable member supporting the rotational motor. By differentially energizing the electromagnets, a force is produced which provides for forward and backward movement of the complete movable member of the reader.

Abstract: In a magnetic floating type of super high speed transportation system using a linear synchronous motor system as its drive system in which a field magnet is carried on a train and a series of armature coils are provided along a track, a speed of a train is regulated under control of a frequency converter of the variable frequency and voltage type for supplying power to the armature coils. For the speed regulation, a relative position of the field magnet to the armature coils is detected to form a train of position detecting pulses. A reference frequency pattern with a frequency corresponding to a speed command is formed. A phase difference between the reference frequency pattern and the position detecting pulse train is detected. A propulsion force command of a linear motor is obtained by setting different limit values in the positive and negative parts of the phase difference signal. A sinusoidal current waveform pattern is formed in synchronism with the position detecting pulse train.

Abstract: A proportional solenoid actuated servo system and associated drive circuitry are disclosed in which a pair of oppositely acting coils of the solenoid are connected in series across a floating power supply with the center point between the coils grounded. The voltages produced at the power supply terminals are differentially controlled relative to ground by voltage control means which responds to position command and armature position feedback signals. The force exerted by the armature is controlled by a power control signal which varies the voltage difference between power supply terminals.

Abstract: There is a recording apparatus utilizing a linear motor in which a movable carriage is provided with a detector for detecting its speed and position while the apparatus itself is provided with a detector for detecting the initial position of the carriage.

Abstract: Mechanically programmable hydraulic linear positioner providing a primemover with the ability to assume and maintain accurately any of an arbitrary number of preselected programmed positions, and to quickly reposition the load from one such preselected detent position to another detent position upon command. A Hall effect magnetic field sensor detects load position and generates command signals directly controlling a proportional hydraulic valve. Rotary and manual positioning applications are described.

Abstract: A reversible linear motor has a coil arrangement arranged alongside a conductive body such as a rotatable aluminium disc. The coil arrangement is made up of three separate coils: namely an inner coil and two interconnected outer coils on opposite sides of the inner coil. The coils are connected to a single phase a.c. supply and the drive of the disc can be reversed by reversing the connection of the inner coil relative to the two outer coils. The linear motor may be used for driving a reel of an entertainment machine of the fruit machine kind.

Abstract: An improved electromagnetic actuator apparatus comprising a plurality of circular concentric tubes of varying length arranged in length order nested about one another from shortest to longest. Solenoid coil assemblies are attached to each tube so that magnetic circuits are formed between adjacent solenoid coil assemblies attached to adjacent tubes. Stops are attached to each tube at the end opposite from the solenoid coil assemblies. One of the shortest tubes is connected to a frame by a positive motion stop in one direction. A return spring connects to a frame on one end and to a carriage attachment member which slides about the shortest concentric tube on the other end. Selective electric excitation of individual solenoid coil assemblies causes translation of said carriage attachment member. The return spring carries the means for carriage attachment back to a rest position when electrical excitation is removed.

Abstract: A rotary actuator assembly for positioning read/write heads in disk drive mass storage systems. The actuator assembly includes an actuator motor and one or more actuator arms secured thereto. The motor provides rotary motion of the arms, to move the heads. The stator magnet of the motor is an electromagnet wound on an arcuate core; a pair of elongate permanent magnets are attached to the rotor member, for coaction with the stator magnet. The rotor member has a U-shaped cross sectional area in a plane perpendicular to its axis of rotation; the permanent magnets are fixed to the outside, bottom corners of the U and the actuator arms are mounted across the open end of the U. The rotor is of a very small radius, to minimize inertia. The permanent magnets have a flat face facing the stator, with a channel running longitudinally down the middle, to minimize flux density variations in the permanent magnet-coil gap. The rotor balances the arm relative to the rotor's axis.

Abstract: Electromagnetic driving mechanism for oscillating displacement pumps (10) is described which comprises a linear motor (21, 22) and a control circuit (51, 52, 53, 54). The control circuit controls the stroke movement of the linear motor (21, 22) in response to the deviation of the actual value of a stroke parameter (stroke distance, stroke speed, stroke acceleration, and pressure of the medium being pumped) from the reference value of this stroke parameter. A preferred embodiment is assembled in such a manner that the pump (10) proper may be easily exchanged and constructed as a discardable unit. Such a pump unit (10) is particularly desirable in connection with blood pumps.

Abstract: A control method and system for quasi-proportionally controlling the magnitude of DC excitation current supplied to the DC field coil windings of a linear reciprocating motor in proportion to the magnitude of the AC excitation current supplied to the AC field coil windings of the motor.

Abstract: Disclosed is an impulse drive device that includes at least one stator having magnetic means to define an array of parallel spaced apart regions of magnetic field with a major component perpendicular to the plane of the stator; a slidor incorporating series-connected conductive strips in an array of similar spacing and orientation to the array of magnetic regions on the stator; and means for generating sequences of current pulses and for delivering those pulses to the conductive strips on the slidor. With appropriate timing and polarity, current pulses in the conductive strips on the slidor can be employed to both accelerate and decelerate the slidor with respect to the stator, thereby permitting rapid controlled movement of the slidor between predetermined positions in its plane.

Abstract: An adaptive interface circuit for use in coupling movement commands to a device utilizing linear actuators to control the rotational position of a rotatable member. Since the rotational position of the rotational member is not a linear function of the extension of the linear member, the rotational controller may be characterized as having a gear ratio which varies with the position of the rotatable member. The system includes an adaptive interface which modifies the gain of the movement commands in a manner designed to offset gear ratio changes so that the system as a whole will respond linearly to the movement commands. The system is described with particular reference to an antenna tracking system.

Abstract: An apparatus for positionally controlling the movable head assembly of a magnetic disc memory unit. In a first state, the head assembly is accelerated under substantially free conditions. In a second or deceleration state, the assembly speed is compared with and regulated by a series of theoretical speeds set in accordance with the actual speed attained by the movable head assembly during the first state.

Abstract: Alignment of a mask and a semiconductor wafer to be processed is effected by orthogonal and angular movements of the mask singly and in combination. A carrier for the mask is supported on four orthogonally positioned transducers which, when actuated to elongate or contract, produce carrier translational movement in either or both orthogonal directions and/or rotational movement by selective elongation and contraction of one or more transducers. Actuation of the transducers and the alignment are obtained by signals from a feedback system including photon detection and multiple frequency oscillation utilizing alignment marks on the mask and the wafer.

Abstract: A device, particularly for driving recording or printing carriages in data recorders and the like, utilizing a linear motor, in which a current carrying coil is movably guided along a pair of ferromagnetic rails which are magnetically polarized by suitable magnetizing means to produce a directional field between the rails, whereby the current carrying coil is moved along the rails in response to current passing through the coil. Means are also provided for controlling the movement of the coil in predetermined stabilized steps.

Abstract: A control system for controlling the relative movement of a head member over a surface such as a plate member in accordance with digital input information. The head member and the surface form a linear, two-axis synchronous motor and the input signal to the head member is controlled to be a translating field vector to produce movement of the head member relative to the surface. The phase of the translating field vector is controlled to lead or lag the position vector of the surface by an electrical angle which is a direction function of the acceleration or deceleration required. An initial acceleration is used to bring the head member up to the desired terminal speed as quickly as possible and with the head then moved at a constant speed until a point when a signal is applied to produce a deceleration to slow down the head so that the head may be stopped at the position on the surface. Additional acceleration and deceleration vectors are provided to control the movement of the head member.

Abstract: For use with an inertial sensing device such as a rate gyro, accelerometer or like device, combined means for sensing an inertial condition and for providing torquing and damping functions for controlling the response of the device to the condition.

Abstract: Means for controlling the speed of the secondary of a linear motor, particularly the shuttle of a linear motor powered loom, consists of a series of uniformly spaced markings on the secondary and a sensor responsive to the markings and located adjacent to the linear motor primary. The markings cause the sensor to produce an oscillating output, the frequency of which is dependent on the speed of the secondary. A control signal derived from the sensor output is used to turn off the supply of current to the linear motor primary when the secondary is travelling at the required speed.

Abstract: A positioning apparatus includes a platen and a head independently movable relative to the platen. First and second coils having a particular phase relationship are disposed relative to each other on the head are independently energized to produce first and second electromagnetic forces. These electromagnetic forces have varying characteristics for moving the head relative to the platen and constant characteristics for maintaining the head in a substantially fixed relationship to the platen. Abrupt changes from the variable to the constant characteristics of the applied electromotive forces allow inertial forces to impart a decaying oscillation of the head about the positional origin determined by the constant characteristics of the applied electromotive force.Oscillation of the head relative to the platen produces first and second back-electromotive force sinusoids in the first and second coils, respectively.