Linear Positioners Catalog_en-US_revA - Kollmorgen

Glossary of Motion Control TerminologyL I N E A R P O S I T I O N E R SAbsolute MoveA move referenced from a fixedabsolute zero position.AccelerationThe change in velocity as a functionof time, going from a lower speed to ahigher speed.AccuracyAn absolute measurement definingthe difference between expected andactual position.ACME (Lead Screw)A screw which uses a threaded screwdesign with sliding surfaces betweenthe screw and nut.Assembly Electric CylinderA self contained system whichconverts rotary motion (from a motor)to linear motion.ASCII (American Standard Code forInformation Interchange)A code which assigns a number toeach numeral and letter of the alphabet.This allows information to betransmitted between machines as aseries of binary numbers.BackdriveTendency of a cylinder to creep out ofits set position due to an applied loador force.BacklashThe amount of play (lost motion)between a set of moveable partswhen changing the direction of travel.Typically seen in drive trains, ball/leadscrews, & bearings.BallscrewA screw assembly which uses a ballnut which houses one or more circuitsof recirculating steel balls which rollbetween the nut and screw.Baud RateThe number of binary bits transmittedper second on a serial communicationlink such as RS232C.BCD (Binary Coded Decimal)A binary numbering system in whichthe decimal digits 0 to 9 are representedby a 4 bit binary number.BinaryNumbering system in which the base istwo, each number being expressed inthe powers of two, by 0 or 1.BearingA support device which allows asmooth, low friction motion betweentwo surfaces loaded against eachother.BushingA cylindrical metal sleeve insertedinto a machine part to reduce frictionbetween moving parts.Closed LoopA positioning system which employsfeedback information to regulate theoutput response.CoggingMotor torque variations which occurat low speeds due to a weak magneticfield.Critical SpeedRotational speed of a ball screw atwhich vibrations (whipping) will occur.CurrentThe flow of charge through aconductor.CycleOne complete extension and retractionof a cylinder.DecelerationThe change in velocity as a functionof time, going from a higher speed to alower speed.Drive RatioThe ratio of motor revolutions per ball/lead screws revolution.Drive TrainThe arrangement by which the motoris coupled to the ball/lead screws.Typically provided by gears, timingbelt/pulley or direct coupling.Duty CycleThe ratio of motor on time and totalcycle time within a given cycle ofoperation.Dwell TimeTime within a move cycle where nomotion occursDutyMotor ON Time(%) = X 100%Cycle Total Cycle TimeEEPROM (Electrically ErasableProgrammable Read Only Memory)Non-volatile data storage chip.EfficiencyRatio of output power vs. input power.EMI (Electromagnetic Interference)Electrical disturbances which interferewith proper transmission of electricalsignals, also known as ”Electricalnoise”.EncoderAn electromechanical device whichproduces discrete electrical pulsesdirectly related to the angular positionof the input shaft, providing highresolution feedback data on position,velocity, and direction.ForceThe action of one body on anotherwhich tends to change the stateof motion of that body. Typicallydescribed in terms of magnitude,direction, and point of application.FrictionThe resistance to motion of twosurfaces that touch.Helical GearGears with teeth that spiral around thegear.Incremental MoveA move referenced from the currentset position.InertiaProperty of an object that resists achange in motion. It is dependent onthe mass and shape of the object.The greater an object’s mass, thegreater its inertia, and the moreforce is necessary to accelerate anddecelerate.LeadThe linear distance a nut will travelwith one revolution of the ball / leadscrew.98K O L L M O R G E N