Resistance WeldingResistance WeldingServogun BasicsServogun Basics

What Is A Servo?What Is A Servo?

1. Motor

2. Feedback Device

3. Controller

Servo MotorServo Motor

Stator Windings

Feedback DeviceNeodymium Iron-Boron magnets in Rotor

Feedback ConnectorPower

Connector

Servo Motor ConfigurationsServo Motor Configurations

Frameless Direct Drive Rotary

Feedback DeviceFeedback Device

Used for motor commutation and position feedback.

• Hall Effect Devices

• Encoders

• Resolvers

Basic EncoderBasic Encoder

Basic ResolverBasic Resolver

Motion ControllerMotion Controller

MotionGenerator

Encoder/

Resolver

Commutationand Current

Loop

Power

Stage Position

Loop Velocity

Loop Motor

Controller Drive / Amplifier

Applying Servos to RWApplying Servos to RW

1. Measurements

2. Integration With Equipment

3. Controlling The Actuator

4. Drive Configurations

5. Equalizing

6. Additional Considerations

Position MeasurementsPosition Measurements

• Gun Open

• Retract Position(s)

• Tip Touch

• Pre-weld position

• Post-weld position

• Electrode wear

Force MeasurementsForce Measurements

• Approach force

• Weld force

• Tip dress force

• Return force

Motor current feedback (motor torque) can be used to determine:

Control ComponentsControl Components

PLCRobot

Controller Mo

tionC

ontroller

Am

plifier

WeldControl

ServoMotor

TeachPendant

ElectronicOperatorInterface

Typical Robot IntegrationTypical Robot Integration

PLC RobotWeld

ControlPLC

RobotController

Am

plifier

ServoMotor

TeachPendant

ElectronicOperatorInterface

Typical Robot IntegrationTypical Robot Integration

Robot Remote AmplifierRobot Remote Amplifier

PLCRobot

Controller

Am

plifier

WeldControl

ServoMotor

TeachPendant

ElectronicOperatorInterface

Robot Retrofit IntegrationRobot Retrofit Integration

PLCRobot

Controller Mo

tionC

ontroller

Am

plifier

WeldControl

ServoMotor

TeachPendant

ElectronicOperatorInterface

Machine IntegrationMachine Integration

PLC

Mo

tion

Controller

Am

plifier

WeldControl

ServoMotor

ElectronicOperatorInterface

Am

plifie

r

ServoMotor

Am

plifier

ServoMotor

Am

plifier

ServoMotor

Controller Integral to Weld ControlController Integral to Weld Control

PLC

Mo

tionC

ontroller

Am

plifie

r

WeldControl

ServoMotor

ElectronicOperatorInterface

Controller Integral to MotorController Integral to Motor

PLCWeld

Control

ElectronicOperatorInterface

ServoMotor

Servo Controller Integral to MotorServo Controller Integral to Motor

Controlling the ActuatorControlling the Actuator

Trapezoidal Move Profile

Controlling the ActuatorControlling the Actuator

P-Curve Move Profile

Controlling the ActuatorControlling the Actuator

S-Curve Move Profile

Controlling the ActuatorControlling the Actuator

Chart courtesy of Savair/ARO

Controlling the ActuatorControlling the Actuator

Controlling the ActuatorControlling the Actuator

Linear MotionLinear Motion

Roller ScrewsRoller Screws

Drive ConfigurationsDrive Configurations

Tubular Linear MotorTubular Linear Motor

Matching the Actuator to the GunMatching the Actuator to the Gun

Gun Ratio =

A

B

A

B

Why is Equalizing Necessary?Why is Equalizing Necessary?

Part Position or Gun Position Error

Expected Actual

Why is Equalizing Necessary?Why is Equalizing Necessary?

Part Fit-up Gap

Why is Equalizing Necessary?Why is Equalizing Necessary?

Cap Wear

Why is Equalizing Necessary?Why is Equalizing Necessary?

• Electrode Deflection

• Weld Indentation

• Metal Thickness Variation

Equalizing ServogunsEqualizing Servoguns

2. Robot Equalization

1. Pneumatic Equalization

3. Servo Equalization

Photo courtesy of Matuschek GmbH

Additional Application Additional Application ConsiderationsConsiderations

1. Training

2. Maintenance

3. Power Consumption

Packaging of Servo Vs PneumaticPackaging of Servo Vs Pneumatic

Resistance WeldingResistance WeldingServogun BasicsServogun Basics

Thanks to the following for providing material to be used in Thanks to the following for providing material to be used in this presentation:this presentation:

CenterLineCenterLine

Savair/AROSavair/ARO

Milco ManufacturingMilco Manufacturing

California Linear DevicesCalifornia Linear Devices

Matuschek GmbHMatuschek GmbH

Nachi RoboticsNachi Robotics

Other Internet SourcesOther Internet Sources