In this presentation, Lin Engineering will cover common stepper motor applications, issues that can arise within those applications, and stepper modifications that can help resolve those problems. Stepper motors are used in a multitude of applications in many different industries. Steppers can be applied to printers, robotics, security cameras, conveyor belts and aircraft in industries like automation, medical, surveillance, and renewable energy just to name a few. Each application is unique and the stepper motor must adapt to each situation. Due to the mechanical and environmental requirements from each system, a number of issues and failures can arise when stepper motors are introduced into such applications. Lin Engineering will discuss the root causes of issues like vibration, excessive heat, Back EMF, inertia mismatch and step loss that are seen while using a stepper motor. Lin Engineering will also explain how to resolve the problems through modifications and describe the effects of adding gearboxes, encoders, lead screws, vacuum and additional environmental modifications to a stepper motor. Why to Watch: Learn what modifications are required of stepper motors in certain applications. Learn what common issues arise from different applications. Learn what applications a stepper motor can be applied to. Learn how to resolve common application issues through stepper modifications.

1. Stepper Motors: Inside and Out

2. Before We Start
 This webinar will be available afterwards at
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 Q&A at the end of the presentation
 Hashtag for this webinar: #DWwebinar

3. Moderator
Miles Budimir
Design World
Presenters
Jim Nimitz
Tom Le
Lin Engineering
Lin Engineering

4. Stepper Motors: Inside and Out
Common Applications, Issues and Solutions
Presented by:
Tom Le & Jim Nimitz
Lin Engineering

5. Lin Engineering
• Started in 1987 as a
consulting firm
• Founded by Ted Lin
• Provides innovative solutions
to motion applications
• Manufacturing in Morgan Hill,
CA and Nanjing, China

6. Industries & Applications
What We Will Discuss:
1. Automation
2. Medical
3. Aerospace and Defense

7. Automation
What We Will Discuss:
1. Common Applications
2. Insufficient Torque
3. Optimizing Torque

8. Automation
• As the Automation Industry expands, it
becomes more dependent on stepper motors
• Optimizing Torque and Smooth Motion from
stepper motors is critical
• Common Applications Include:
o Semiconductor Linear Stages
o X – Y Table (2 Axis Movement)
o 3D Printers
o Cutting Machinery

9. Automation
Semiconductor Linear Stages:

10. Automation
Cutting Machinery:

11. Automation – Linear Stages
• Used to give loads linear motion
• Can be used in a horizontal or
vertical axis
• Stepper motors must provide
smooth motion and high positional
accuracy
• Higher operating speeds require
steppers to maintain torque output

12. Insufficient Torque
Torque- Rotational Force
• Magnetic Interaction
between Coils and the
Rotor
• Dynamic Torque decreases
as Speed increases

13. Insufficient Torque
• Larger motors generate
more torque
• Greater Rotor Inertia and
magnetic interaction
• Many applications are
limited to a size constraint

14. Torque Case Study
Customer’s Problem:
Could Not Generate
Enough Dynamic
Torque at Desired
Operating Speed

15. Optimizing Torque
Customized Motor Windings
• Customized Windings for
Optimized Performance
• Can Change Wire Gauge and
Turns per Coil to Tailor Motor
Performance

16. Optimizing Torque
• Higher Inductance
Lowers Dynamic Torque
at Higher RPM
• Higher Inductance at
Higher Speed Doesn’t
Allow Current to Reach
Rated Value

17. Optimizing Torque
Power In vs. Power Out
• Can Optimize the
Winding for the Highest
Motor Efficiency

18. Solution : Torque Case Study
Proposed Solution:
By Optimizing the
Winding, the Motor
can Generate the
Required Torque at
the Desired
Operating Speed

19. Optimizing Torque
Gearbox and Pulley Assembly
• Gearboxes and Pulleys can
be used to Produce more
Torque

20. Medical
What We Will Discuss:
1. Common Applications
2. Resonance
3. Reducing Resonance

21. Medical Industry
• Medical Devices require smooth motion and
reliability from steppers.
• Therefore the motors must run accurately
without interference.
• Common Applications Include:
o Respirators
o Prescription Dispensers
o Blood Analysis Machinery

22. Medical Industry
Prescription Dispensers:

23. Medical Industry
Analysis Machinery:

24. Medical – Respiratory Machinery
• Medical Device used to Remove
Mucus from patient airways
• Requires high holding torque,
accurate positioning, and
position feedback
• Cannot overstep or miss steps

25. Resonance
When the frequency of a system’s oscillations
matches the natural frequency of the system.

26. Electrical Resonance
Stepper Motor Resonance:
- At certain frequencies, the energy is transferred
to the motor body.
- Natural step response is oscillatory

27. Resonance
•
Every stepper system has
unique resonance points
•
Resonance can cause the
system to: jitter, skip steps,
lose accuracy, and even stall
out.
•
The system resonance leads
to a loss of motor torque at
defined motor frequencies;
see the torque v. speed curve

28. Reducing Resonance
• Microstepping – Oscillations per
step decrease greatly as steps
become finer.
• Current: The motor can be
overpowering. Many low speed
applications will run smoother
with reduced current (i.e. Lower
the dT/dθ, torque stiffness)

29. Reducing Resonance
R-Winding
• Created to reduce noise
and vibration for lowertorque applications
• Designed to eliminate the
one-phase on position

30. Reducing Resonance
Mechanical Damping
• Inertia Damping
• Friction Damping,
Flange-mount damper
Electrical Damping
• Driver Settings, Microstepping
• Special Windings

31. Reducing Resonance
Inertia Damper
• Contains an inertia body
and elastomeric material
• Counters the effects of
inertia
• Suppresses vibration

32. Aerospace and Defense
What We Will Discuss:
1. Common Applications
2. Environmental
Contamination
3. High and Low
Temperatures

33. Aerospace and Defense
• Require rugged, long lasting and
high performance motors that
can withstand harsh
environments
• Lin Engineering provided motors
used in the B-2 Stealth Bomber
• Examples
o
o
o
o
Satellites
Ground Vehicles
Targeting System
Aircraft Ventilation

34. Heat Generation
Copper Loss:
• Interaction between
current and resistance of
the winding creates heat
Iron Loss:
• Related to the magnetic
field interactions

35. High & Low Temperature
• Standard Motors (Class B)
• Temperature Classes
Temperature
Tolerance Class
A
B
F
H
Maximum Operation
Temperature Allowed
°C
°F
105
221
130
266
155
311
180
356

36. High & Low Temperature
High Temperature
• Bearing Grease, Teflon Leads, Class
H/F Insulator and Magnet Wires,
Special Magnets
Low Temperature
• Bearing Grease
• Teflon Leads

37. Environmental Protection
IP Rating ( IP XX)
• Protects Motor
Against Solid
Objects and
Liquids

38. Environmental Contamination
Wash Down Applications
• Motors subject to rain need
protection from liquid or solid
ingress
• Moisture in between the rotor
and stator can lead to rust
• Particles within the air gap can
cause the motor to lock up

39. Environmental Protection
IP 65
• Protected Against Dust,
Low Pressure Jets of Water
• Better Protection from
Environmental Elements

40. Environmental Protection
IP X7
• Protected Against Dust;
Submersible in Depths of
15cm to 1m
• Better Protection from
Damaging Environmental
Elements

41. Aerospace and Defense – Aircraft Ventilation
• Steppers require protection
from the environment (i.e.
rain, moisture, pressure)
• Must operate in extreme
temperatures; high and low

42. Environmental Protection

43. Thank You!
Tom Le: Applications Engineer
tle@linengineering.com
Jim Nimitz: Sales Engineer
jnimitz@linengineering.com
Tech Support: 408-919-0200

44. Questions?
Design World
Miles Budimir
mbudimir@wtwhmedia.com
Phone: 440.234.4531
Twitter: @DW_Motion
Lin Engineering
Jim Nimitz
jnimitz@linengineering.com
Phone: 408.919.0200 ext. 233
Lin Engineering
Tom Le
tle@linengineering.com
Phone: 408.919.0200 ext. 457

45. Thank You
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