Mechanical Components

• What is an axle?

  A rigid bar or shaft that supports a rotating wheel or gear, typically located at the center of the wheel to allow it to rotate.
• What Products use wheels on an axel?

  • Windmills
  • Taps
  • Ferris Wheels
  • Door Knobs
  • Cars
  • Steering Wheels
  • Bikes
• What are gears?

  Toothed wheels attached to driver and driven shafts. Their teeth are shaped to fit into those of another gear, allowing them to mesh together and transfer motion.
• What are Small gears called?

  Pinion gears
• What are Large Gears called?

  Gear wheels
• What is a Number of gears connected together?

  A gear train
• What is a pulley?

  A pulley is a wheel with a belt or rope that goes around it.
• What type of motion do pulleys transmit?

  Pulleys transmit rotary motion over a distance.
• What is the purpose of a pulley system in machinery?

  To wind in or out a rope or cable, such as for lifting or moving objects.
• What is the driver pulley?

  The smaller pulley connected to the motor that provides input energy.
• What is the driven pulley?

  The larger pulley that is turned by the driver via the belt.
• Why is the belt pulled tight in a pulley system?

  To create tension and friction so the driven pulley follows the driver without slipping.
• What would happen if the belt in a pulley system was loose?

  The belt would slip, and the pulley system would fail to work properly.
• What feature prevents a belt from slipping off the pulley?

  Pulleys are grooved or flanged to keep the belt in place.
• What is a V-belt and why is it commonly used?

  A V-belt fits tightly into a groove, increasing friction and reducing slippage — it's the most commonly used belt type.
• What are round belts used for?

  Light machines where only small force is needed, like toys, small power tools, and vacuum cleaners.
• Why does a V-belt provide more grip than a round belt?

  Because more of the V-belt is in contact with the pulley, increasing friction.
• What does the belt do in a pulley system?

  It transfers motion and power from the driver to the driven pulley.
• What is velocity ratio in pulley systems?

  The difference in speed between the driver and driven pulleys.
• What happens when a small pulley is connected to a large pulley?

  The small pulley will turn faster than the large one.
• Why do smaller pulleys turn more than larger pulleys in a system?

  To keep up with the rotation of the larger pulley.
• What is the formula for velocity ratio (VR) in pulley systems?

  $VR\ =$$\frac{Diamater\ of\ the\ driven\ pulley}{Diamter\ of\ the\ driver\ pulley}$
• What information do you need to calculate pulley speeds?

  You need the diameter, radius, or circumference of the pulleys.
• Why is knowing the speed of the driver pulley important?

  So you can control the speed of the driven pulley/shaft accurately.
• What type of motion is transmitted by pulleys?

  Rotary motion.
• How does pulley size affect speed?

  Smaller pulleys rotate faster; larger pulleys rotate slower.
• What is the purpose of a ‘key’ in a pulley system?

  To lock the pulley wheel to the shaft so it cannot slip during rotation.
• How is the key used in a pulley system?

  A small rectangular key is tapped into a slot between the shaft and the pulley to hold them together.
• What is the main purpose of a keyed shaft?

  To ensure the pulley and shaft rotate together without slipping.
• How can a pulley system change the direction of motion?

  By crossing the belt between the driver and driven pulleys.
• What is one disadvantage of using belts in pulley systems?

  The belt can slip, which may reduce power transmission.
• When can belt slippage be an advantage?

  in machines like pillar drills, slippage can prevent injury and protect the motor if the drill jams.
• Give three advantages of belt and pulley systems.

  • Quiet in operation
  • Require no lubrication
  • Cheap to produce
• What are key safety precautions to follow when using mechanical systems or machines?

  • Keep fingers clear of moving parts.
  • Never try to remove obstructions while a machine is moving.
  • Keep moving parts clean to prevent obstructions.
  • Never attempt to slow down a moving part with your hands.
  • Make sure guards are in place before starting the machine.
• How should you dress and protect yourself when using mechanical equipment?

  • Wear proper clothing and tie back long hair to prevent it from getting caught.
  • Always wear eye protection to guard against flying debris.