gears

• What are the four types of movements linked to mechanical devices?

  Linear, reciprocating, oscillating, rotary
• What is a simple gear train?

  A simple gear train uses two gears of different sizes
• What is the driver gear in a gear system?

  The driver gear is attached to a motor or crank
• What is the driven gear in a gear system?

  The driven gear is turned by the driver gear
• What happens to the direction of the driven gear in a simple gear train?

  It reverses the driven gear's direction
• What is the velocity ratio in a gear system?

  The amount of change in speed between gears
• What is a simple gear train designed to do?

  Transmit maximum torque without slip
• In a gear system, if gear A has 30 teeth and gear B has 20 teeth, how many times does gear B turn when gear A completes one revolution?

  Gear B turns 1.5 times
• How do you calculate the velocity ratio (VR) of a gear system?

  VR = Number of teeth on driven gear / Number of teeth on driver gear
• What is a compound gear system used for?

  • Achieve a larger speed change
  • Combine the VR of both pairs of gears
• What is an idler gear?

  An idler gear rotates in the opposite direction without affecting output speed
• What is the role of an idler gear in a gear system?

  It can change the direction of rotation of the output shaft
• How does the idler gear assist in gear systems?

  It reduces the size of input/output gears while maintaining shaft spacing
• What does rpm stand for in mechanical devices?

  Revolutions per minute
• How is output speed calculated in a gear system?

  Output Speed = Input Speed / Gear ratio
• How is the gear ratio calculated?

  Gear ratio Z = Number of teeth on driven gear / Number of teeth on driver gear
• What are common examples of idler gears used for?

  • Connecting a metal motor shaft to a metal platter
  • Connecting two crankshafts to a common shaft
  • Transmitting power in a lathe machine
• What are bevel gears used for?

  To transmit rotary motion through 90 degrees
• How can bevel gears vary in a gear system?

  They can vary in size to achieve different gear ratios and output speeds
• What is the purpose of rack and pinion gears?

  To convert rotation into linear motion
• How does the steering system in cars utilize rack and pinion gears?

  The steering wheel rotates a gear that engages the rack
• If a cyclist is pedaling with a drive gear of 50 teeth and a driven gear of 25 teeth, what is the gear ratio?

  Gear ratio = 0.5 or 1:2