Electromagnetic Actuator-Solinoid

1
Electromagnetic Actuator-Solinoid

• Noah A. Sundberg
• ECE 5320 Mechatronics
• Assignment 1

2
Outline

• Resources
• Related Web Pages
• Introduction
• Major applications
• Specific applications and uses
• How it works
• Principles Behind Solenoids
• Example 1
• Specifications
• Selecting a Solenoid
• Limitations

3
Resources

• Mechatronics Handbook, Robert H. Bishop, CRS
  Press
• Integrated Publishing www.tpub.com/content/doe/h10
  13v2/css/h1013v2_166.htm

4
Related Web Pages

• How Stuff works
• science.howstuffworks.com/electromagnet3.htm
• Integrated publishing
• www.tpub.com/content/doe/h1013v2/css/h1013v2_166.h
  tm
• Jewel Instruments
• www.wpiinstruments.com/solenoids/theory.htm

5
Introduction

• A solinoid is the most common type of
  electromagnetic acutuators.
• A solinoid consists of an Iron core surrounded by
  coiled wire. When the coils have current flowing
  through them they create a magnetic field that
  pushes or pulls on the iron core depending on
  what direction the current is flowing.

6
Major Applications

• Solenoids are used in
• Valves
• Water valves
• Gas valves
• Relays
• Power relays
• Switches

7
Specific applications and uses

• Automatic Door locks
• Office Equipment/ Printers
• Electric/ Electronic Locks
• Photographic/ Optical
• Medical Instrumentation
• Coin and Bill Changers
• Cash Drawers and Automatic Teller Machines

8
How it works

• Principles Behind Solenoids
• -Lorentzs law of electro magnetic induction
  states that a magnetic flux (theta) exists due to
  a magnetic field
• The fields strength is H and the flux density is
  B and are related by the magnetic permeability of
  the substance that the field is in.

9
How it works (continued)

• Principles Behind Solenoids-Continued
• -Faradays Law of Electromagnetic Induction
  states that a change in the electromotive force
  (emf) or Voltage across the conductor causes a
  change in the flux.
• There for current creates magnetic flux as is
  shown in fig 1(Mechatronics Handbook)

Fig 1
10
How it works (continued)

• Principles Behind Solenoids-Continued
• -As shown in figure 3 and 4 (found in the
  Mechatronics Handbook) in a solenoid utilizes
  these characteristics to cause a B field in one
  direction
• The strength of the field depends on the length
  of the solenoid (L) the number of turns (N) the
  magnetic permeability u and the current i

Fig 3
Fig 4
11
How it works (continued)

• Example 1 Valve
• A spring maintains the valve in its closed or
  open position. When a current is produced the
  coils around the core
• Produce a magnetic force
• That pushes the valve to the
• Open or closed position
• When the current is stopped
• The force is removed and
• The valve moves to its original
• Position. The set up of this
• Can be seen in figure 1(from www.tpub.com/
• content/doe/h1013v2/
• css/h1013v2_166.htm)

Fig. 2
12
Specifications

• current driving solenoid
• Initially open or closed
• DC or AC
• Number of Turns
• Voltage maintaining the core in position

13
Selecting a Solenoid

• Many mechanical, thermal, and electrical
  constraints should be considered when selecting a
  solenoid.
• Force requirements
• Electrical requirements (current driving actuator
  etc.)
• Duty cycle
• Maximum envelope dimensions
• Temperature extremes
• Termination requirements
• Dimensions

14
Limitations

• Current flowing through coil
• Dimension
• Voltage across the coil
• Distance the armature needs to move

15
Where to Buy

• WellGrow industries Corp.
• www.fittings.com.tw
• Command Alarms
• www.commandocaralarms.com/solenoids_actuators.asp
  
• Saia Burgess
• www.ledex.com/df/LXGOG/index.html
• Alltronics.com
• www.alltronics.com/relays.htm
• PennGiles
• www.pennyandgiles.com/products/products.asp?strAr
  eaNo402_12
• Corrosion Fluid Products Corp.
• www.corrosionfluid.com/Products/valves/actuators.
  htm