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Explanation of Terms   (IAI Glossary)

 This terminology is related to IAI products, and so the definitions are more limited than general meaning.

A phase (signal) output · B phase (signal) outputThe incremental type output judges the forward and reverse rotation of the axis with the phase difference between A phase and B phase. In the case of forward rotation (CW), the A phase precedes the B phase.
A transistorWhen a small amount of current is passed through the base (B) part, current flows between the collector (C) and the emitter (E), and it functions as a switching element. There are two types, PNP type and NPN type.
Absolute batteryBattery to hold encoder information when power is cut off.
Absolute encoderEncoder with absolute position detection function. Since absolute position can always be grasped, return to home is not required every time power is turned on.
Air purgeTo ensure dust-proof and drip-proof properties in dust-proof and drip-proof type actuators, apply air pressure inside the actuator to prevent dust and other substances from entering the inside of the actuator.
Allowable Dynamic MomentIndicator for guide life. In our company, the moment where the mileage is 5,000 km for ROBO Cylinder and 10,000 km for Single Axis Robot shall be the standard rated life.
Allowable Static MomentCalculated based on the static load rating (N) * 1 that can be added to the
slider while the slider is stopped.
*1 When a certain load is applied, a small indentation (the total permanent deformation amount of the guide ball becomes about 1/10000 times the ball diameter) remains on the contact surface between the guide and the ball (steel ball)).
AQ sealLubricating components obtained by solidifying lubricating oil with resin. Lubricating oil seeps out to the surface due to capillary phenomenon, the optimal amount of oil is secured on the raceway surface of the ball screw / linear guide, and lubricating performance is maintained.
BacklashGaps between the mechanical elements that move together.
Backup memoryA storage device for storing information necessary for moving the actuator in the controller.
Ball screw (Ballscrew)Machine parts where the screw shaft and nut operate through the ball.
BellowsA stretched sheet that is mounted for dust-proof or drip-proof purposes.
Belt driveDrive system that transmits power from drive shaft to driven shaft (driven shaft) with belt. IAI mainly uses toothed belts.
BitUnit of information amount in the network. In addition, there are byte
(word) and word (word).
The amount of information that can be handled in order of minimum bit, next byte, maximum word changes.
Concept: 8 bits = 1 byte, 16 bits = 2 bytes = 1 word
Brake boxA device to be connected between the brake controller.
CCWCounter clock wise.
It is used to indicate the direction of rotation of the motor.
CircuitIt is defined as "the one to operate the contact mechanism by using the electromagnetic suction force caused when the current more than the value in the electromagnet is flowed" composed of the electromagnet and the contact mechanism. The contacts are opened and closed by voltage and current (input signal) applied to the coil.
CleanlinessAn index showing the cleanliness in a clean room.
CoilA component that generates an electromotive force proportional to a change in current per unit time when the flowing current changes. There is a property that only high-frequency electric signals are passed through, and only direct current or low-frequency alternating current is passed.
CondenserPassive element that acts to store electric charge. Also referred to as electrostatic capacity or capacitor.
CouplingShaft coupling. Machine element for fastening shaft and shaft.
CP controlControl with all orbits or all routes specified. (Continuous Path)
Creep sensorSensor for returning to home at high speed.
Critical speedThe speed of the slider where the ball screw resonates. (Ball screw rotation speed)
CT effectBy replacing the air cylinder of the facility with an electric actuator, it is possible to shorten the cycle time and reduce Choco Tei. As a result of improved productivity, capital investment and personnel expenses can be suppressed and the benefit of increasing customer profits. CT is an abbreviation for Cycle Time and Choco Tei.
CWClockwise (Clock Wise). It is used to indicate the direction of rotation of the motor.
Cycle timeThe time taken for one process.
Differential line driverIt is one of the input / output method of the pulse train signal, and has the feature that it is more resistant to noise than the "open collector" method of the same input / output method. On the other hand, it is more expensive than the open collector type.
DiodeA part that makes the flow of electricity one way.
1. Switching diode
It is used most frequently for small signal diodes.
The shape is also small and it is sealed with glass.
2. Light emitting diode
LED. It is used for display, infrared remote control etc.
Direct numerical designation controlA control method in which a numerical value is entered from a touch panel and is directly reflected on the target position even if the target position is not memorized in the controller in advance.
DispenserEquipment that restricts the flow of liquids. It is incorporated into adhesive and sealant coating equipment.
Double sliderA free slider (slider not connected to the ball screw/drive belt) is added separately from the drive slider.
DutyThe ratio between the time the actuator is operating and the elapsed time.
EarthConnect the equipment casing, the reference potential wiring of the electronic equipment, etc. to the reference potential point. Or the reference potential point itself. It is connected for the purpose of noise countermeasure, electric shock prevention, etc. (Ground, ground)
Emergency stop circuitCircuit that stops the device either artificially or automatically if the device is in a hazardous state.
EncoderSensor that detects the position of the motor.

An incremental encoder:
detects the rotational angle and the RPM of the axis from the number of output pulses. To detect the rotational angle and the RPM, a counter is needed to cumulatively add the number of output pulses. An incremental encoder allows you to electrically increase the resolution by using the rise and fall points on the pulse aveform to double or quadruple the pulse generation frequency.
An absolute encoder:
detects the rotation angle of the axis from the state of the rotation slit, enabling you to know the absolute position at all times, even when the rotating slit is at rest. Consequently, the rotational position of the axis can always be checked even without a counter.
In addition, since the home position of the input rotation axis is determined at the time it is assembled into the machine, the number of rotations from home can always be accurately expressed, even when turning the power ON during startup or after a power outage or an emergency stop.
External operation modeAn operation mode activated by a start signal of an external device (PLC etc.). (self-driving)
Feedback controlA mechanism to control so that the control results from the controller and the command from the encoder can match.
There are the following types of control of the actuator.
Flexible HosesA pipe that is through the motor, encoder cables and user wiring of SCARA robot. Flexible hose, flexible tube and so on.
Frame groundA place with a stable electric potential consisting of a large conductor such as the frame of the equipment.
GA unit representing the magnitude of acceleration. Non SI unit. Acceleration is indicated based on standard gravity acceleration. 1 G = 9.807 m/s2
GainA numerical value that adjusts the response when the controller controls the servomotor. Generally, the higher the gain, the more quick response is improved.
GantryCombination type with a guide for Y axis support attached to XY 2 axis combination.
Global specificationType of controller and teaching box equipped with functions such as duplex emergency stop circuit and 3 position enable switch so that it can
correspond to safety category.
Grease upInjecting and applying grease to sliding parts.
GreaseSuspended thickener in lubricating oil to make it semisolid or solid.
GroundA place that becomes a reference potential that is installed in the earth and used for security.
Guide moduleGuide mechanism with drive mechanism removed from direct acting actuator.
HomeReference point of actuator operation.
HuntingThe phenomenon in which the response is vibrating near the target value.
I/OInput / Output (Input / Output). An interface used for input and output information (signal) with devices connected to the outside of the device.
Incremental encoderEncoder with the function to detect the relative position. Since only the relative position can be grasped, return to home is required every time the power is turned on.
Inertia ratioRatio of load inertia moment to moment of inertia of motor shaft.
InertiaAs long as no external force acts on the object, it is a property to sustain the current state.
Inrush currentCurrent flowing to charge the capacitor at the moment of power-on. It is much larger than the steady state current.
Intermediate support mechanismA ball screw support mechanism that moves in conjunction with a slider. A mechanism that greatly improves the maximum speed of the long stroke type, suppressing the runout of the ball screw in the case of long stroke, increasing the band of critical revolution number.
Jog feedSend it manually at a predetermined feed speed.
Key GroovesThe grooves to be machined into the shaft or mounting parts for key mounting. (Key: The part to prevent the position shift in the rotation direction of the shaft and the mounting part.)
LeadDistance at which the slider moves when the feed screw rotates once. When the lead is large, the speed of the slider is fast, but the thrust is small.
Leak currentIt is a small current flowing from a part etc. used in a device using a high voltage power supply (AC 100 V etc.) to a surrounding conductor (mainly a frame).
Linear encoderEncoder to detect linear distance.
Linear guideMechanism for guiding the slider of the actuator.
Linear motorMotor that performs linear motion.
Load CoefficientCoefficient to consider lifetime reduction due to operating conditions in lifetime calculation.
Load RatingThe ratio of the load to the rated output of the motor.
Load cellSensor that detects the magnitude of force.
Lost motionDifference between both stopping positions by positioning in a positive direction to a certain position and positioning in a negative direction. Repeat positioning from positive and negative directions seven times at an arbitrary point, measure the stop position, and find the average difference between the positive and negative measured values. This measurement is performed at the center of the moving distance and almost at both ends, and the largest one of the obtained average differences is taken as the measured value.
Ma directionFront-to-rear direction with respect to the traveling direction.
Mb directionHorizontal direction with respect to the traveling direction.
Mc directionRotational direction with respect to the direction of travel.
Mechanical endMechanical movable limit position of the slider.
Moment of inertiaThe amount that indicates the degree of difficulty of rotation (difficulty of stopping).
MomentThe power to try to rotate the object.
Motor / encoder cableCable connecting the actuator and the controller.
Multi SliderSpecifications equipped with multiple sliders that can be operated individually.
N∙mUnit of force moment (torque) in SI unit system. The moment of force around the center point is 1 N∙m when 1 N force is applied in the direction perpendicular to the center point to the point 1 m away from the center point.
NUnit of force in SI unit system. It shows the force to accelerate an object with a mass of 1 kg at 1 m/s2. 1 kgf = 9.807 N
Noise filterEquipment that prevents leakage or intrusion of noise in power supplies, signals, etc.
NoiseDistortion of electrical signal caused by unnecessary electromagnetic wave leaked from equipment.
Open collector outputA system with no overload resistance in the voltage output circuit, that outputs signals by sinking the load current. Since this circuit can turn the load current ON/OFF regardless of voltage potential to which the current is connected, it is useful for switching an external load and is widely used as a relay or ramp circuit or the like for switching external loads, etc.
Open loop systemA type of control system. This system only outputs commands and does not take feedback.
A typical example of this is the stepping motor. Since it does not compare each actual value against the commanded value, even if a loss of synchronization (i.e signal error) occurs, the controller would not be able to correct it.
Overhang load lengthEstimated maximum length that can be extended from the slider.
OverhangThe object to be mounted on the actuator protrudes in either front, back, left, right, up or down.
Overload checkCheck overload. (One of protection functions)
OvershootThe response goes over the target value too much.
OvervoltageVoltage above the specified value will be applied to the motor.
ParameterThe data that the controller holds to operate the actuator, such as setting the input and output of the signal and how the voltage and current for rotating the motor are changed.
Payload quantityMass which can be conveyed by actuator slider / rod / table.
PitchingIt is an angle that shows how far it is inclined in the fore-and-aft direction (Ma direction) with respect to the traveling direction.
PLCAbbreviation for Programmable Logic Controller. Programmable controller for controlling production facilities / equipment.
Positioning accuracyThe degree of coincidence between the commanded stop position and the actually stopped position.
Positioning complete widthWidth regarded as positioning completion with respect to the coordinates to be positioned. (Pend Band)
Protective structure (IP□□)The degree of protection from water, human body and solid foreign matter.
It is based on the standards of IEC (International Electrotechnical Commission), JIS (Japan Industrial Standard) and JEMA (Japan Electric Industry Association).
ProtocolConventions stipulated mainly when communicating. It decided how to arrange the data and give meaning.
PTP controlControl where pass points on the route are specified intermittently. (Point to Point)
Pulse Train ControlA method that controls the operation of the motor by modulating the pulse train output by the driver.
Push and return to originA method of determining the hime position by pushing against a stopper. Return to home is possible without using the home sensor.
Radial loadLoad acting perpendicularly to the direction of motion of the direct acting actuator.
Rated thrustThrust that can be generated continuously.
Rated torqueTorque that can be generated continuously.
Reference rated lifeStandard value of running life. We have set the standard rated life of ROBO Cylinder to 5,000 km and the standard rated life of single axis robot to 10,000 km. (Except some models)
Regenerative brakeIt is a brake that uses the rotational resistance generated when the motor decelerates as a braking force.
Regenerative energyEnergy generated by itself when the motor rotates.
Regenerative resistorResistance to discharge regenerative current.
Repetitive positioning accuracyReproducibility when repeatedly positioned by the same command under the same condition.
Repeat positioning from the same direction to an arbitrary point seven times, measure the stop position, and find the maximum difference in reading. This measurement is performed at the center of the moving distance and almost at both ends, and the maximum one of the obtained values is taken as the measured value, and 1/2 of the value is displayed with a sign of ±.
Return to homeGo back to the point that is the basis of the movement of the actuator.
Robot cableA cable excellent in resistance to bending and twisting.
RollingIt is an angle that shows how tilted in the direction of rotation (Mc direction) with respect to the direction of travel.
Safety categoryIt is prescribed by ISO 13849-1 of the international standard and classified as a function (safety function) to ensure safety. Classification is divided into 5 stages of B, 1, 2, 3, and 4 according to safety standards, and the standard (category)
4 indicates the standard with the highest safety.
ScraperA part for removing foreign objects on the sliding surface and preventing intrusion into the inside of the main body.
SEL languageAbbreviation for Shimizukiden Ecology Language. Our proprietary programming language.
Serial communicationUse one or two transmission lines to send and receive data.
1bit is a communication method that transmits and receives continuously.
Servo controlA control method that detects the current speed and position from the motor and compares the actual result against the command value by feeding back the result to the upper side to make the difference as small as possible.
ServomotorMotor operated by giving feedback.
Settling timeIn the positioning operation, it means the time until the speed command value becomes zero and then stops.
Shielded wireAn electric wire structured by covering the core wire with an electrostatic shield (aluminum tape, netting etc). It is less sensitive to noise.
Single phase ACAC consisting of one phase. It is used for household power supply etc.
Software limitLimit of operating range set on software.
Solenoid valve typeThe type of controller that made it possible to operate with the same signal as the signal operating the solenoid valve of the air cylinder.
Stainless steel sheetDust-proof sheet used for slider type.
Standard load factorThe standard value of the load factor set for each model.
Step-outSynchronization between input pulse signal (command position) and motor rotation (position after movement) is lost due to shock, overload, etc. In the open-loop control, it is impossible to detect step-out, so the operation is continued with the position shift.
Stepping motorMotor for angular positioning by input pulse signal. Also called a pulse motor.
StrokeOperating range of the actuator.
SwitchIt is made possible to connect and shut off the path of electricity by lever or push button.

1 Toggle switch (snap switch)
Switch to turn ON / OFF by tilting the lever. There are 2P, 3P, 6P
depending on the pin pin number.
2 Momentary switch
A switch that turns ON when the operation part is pushed, and returns
to the original when you release the hand.
3 Alternate switch
A switch that holds the ON state even when you release your hand and turns it OFF when you press it again.
Tact timeIn the production line, within a certain time, the working time per piece allocated to produce target production quantity. (Planned value)
TeachingMake the controller store the information necessary for the required work. (Teaching)
Three phase ACExchange consisting of three phases. Since it can transmit with less current compared with single phase, it is widely used for power supply.
Thrust loadLoad applied in the axial direction. (Axial load)
TimerAn electronic component that can be activated after an electrical start signal is given, and can switch circuits after a predetermined time has passed.
TranceElectrical equipment or parts that convert AC voltage or current.
Vision SensorA device that uses a camera to capture an object (a workpiece), read a position or contour, and send data to a control device.
YawingIt is an angle that shows how much it tilts in the left-right direction (Mb direction) with respect to the traveling direction.
Z phaseIt is a phase (signal) that detects the reference point of the incremental encoder and is used to detect the origin during home return operation. Searching the
Z phase signal serving as a reference during the homing operation is called
Z phase search.

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