Stepper Motors: Inside and Out

953 views

Published on

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.

Published in: Technology, Business
0 Comments
1 Like
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total views
953
On SlideShare
0
From Embeds
0
Number of Embeds
2
Actions
Shares
0
Downloads
34
Comments
0
Likes
1
Embeds 0
No embeds

No notes for slide

Stepper Motors: Inside and Out

  1. 1. Stepper Motors: Inside and Out
  2. 2. Before We Start  This webinar will be available afterwards at designworldonline.com & email  Q&A at the end of the presentation  Hashtag for this webinar: #DWwebinar
  3. 3. Moderator Miles Budimir Design World Presenters Jim Nimitz Tom Le Lin Engineering Lin Engineering
  4. 4. Stepper Motors: Inside and Out Common Applications, Issues and Solutions Presented by: Tom Le & Jim Nimitz Lin Engineering
  5. 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. 6. Industries & Applications What We Will Discuss: 1. Automation 2. Medical 3. Aerospace and Defense
  7. 7. Automation What We Will Discuss: 1. Common Applications 2. Insufficient Torque 3. Optimizing Torque
  8. 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. 9. Automation Semiconductor Linear Stages:
  10. 10. Automation Cutting Machinery:
  11. 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. 12. Insufficient Torque Torque- Rotational Force • Magnetic Interaction between Coils and the Rotor • Dynamic Torque decreases as Speed increases
  13. 13. Insufficient Torque • Larger motors generate more torque • Greater Rotor Inertia and magnetic interaction • Many applications are limited to a size constraint
  14. 14. Torque Case Study Customer’s Problem: Could Not Generate Enough Dynamic Torque at Desired Operating Speed
  15. 15. Optimizing Torque Customized Motor Windings • Customized Windings for Optimized Performance • Can Change Wire Gauge and Turns per Coil to Tailor Motor Performance
  16. 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. 17. Optimizing Torque Power In vs. Power Out • Can Optimize the Winding for the Highest Motor Efficiency
  18. 18. Solution : Torque Case Study Proposed Solution: By Optimizing the Winding, the Motor can Generate the Required Torque at the Desired Operating Speed
  19. 19. Optimizing Torque Gearbox and Pulley Assembly • Gearboxes and Pulleys can be used to Produce more Torque
  20. 20. Medical What We Will Discuss: 1. Common Applications 2. Resonance 3. Reducing Resonance
  21. 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. 22. Medical Industry Prescription Dispensers:
  23. 23. Medical Industry Analysis Machinery:
  24. 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. 25. Resonance When the frequency of a system’s oscillations matches the natural frequency of the system.
  26. 26. Electrical Resonance Stepper Motor Resonance: - At certain frequencies, the energy is transferred to the motor body. - Natural step response is oscillatory
  27. 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. 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. 29. Reducing Resonance R-Winding • Created to reduce noise and vibration for lowertorque applications • Designed to eliminate the one-phase on position
  30. 30. Reducing Resonance Mechanical Damping • Inertia Damping • Friction Damping, Flange-mount damper Electrical Damping • Driver Settings, Microstepping • Special Windings
  31. 31. Reducing Resonance Inertia Damper • Contains an inertia body and elastomeric material • Counters the effects of inertia • Suppresses vibration
  32. 32. Aerospace and Defense What We Will Discuss: 1. Common Applications 2. Environmental Contamination 3. High and Low Temperatures
  33. 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. 34. Heat Generation Copper Loss: • Interaction between current and resistance of the winding creates heat Iron Loss: • Related to the magnetic field interactions
  35. 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. 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. 37. Environmental Protection IP Rating ( IP XX) • Protects Motor Against Solid Objects and Liquids
  38. 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. 39. Environmental Protection IP 65 • Protected Against Dust, Low Pressure Jets of Water • Better Protection from Environmental Elements
  40. 40. Environmental Protection IP X7 • Protected Against Dust; Submersible in Depths of 15cm to 1m • Better Protection from Damaging Environmental Elements
  41. 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. 42. Environmental Protection
  43. 43. Thank You! Tom Le: Applications Engineer tle@linengineering.com Jim Nimitz: Sales Engineer jnimitz@linengineering.com Tech Support: 408-919-0200
  44. 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. 45. Thank You  This webinar will be available at designworldonline.com & email  Tweet with hashtag #DWwebinar  Connect with  Discuss this on EngineeringExchange.com

×