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MECHANISMS - Coggle Diagram

- - - - A fixed pulley is a wheel that has a groove around lt into which a rope, cham or belt fits.
        It rotates around an axle that is fixed to an immobile surface.
      - A fixed pulley is balanced when the effort F is equal to the resistance of the
        load, R
        
        F = R
    - - This is a system of fixed and moveable pulleys, often called block and
        tackle.
      - (n = the number of movable pulleys)
        
        F = R/(2×N)
        
        F = R/2ⁿ
    - - A lever is a rigid bar that is supported by a fulcrum.
        
        F is the force or effort appbed at one end of the bar.
        
        R is the resistance or load which acts at the other end of the bar.
        
        d is the distance from F to the fulcrum.
        
        r is the distance from R to the fulcrum.
        
        The main formula:
        
        It's called the law of the lever.
        
        F × d = R × r
      - There are 3 types of levers:
        
        Class 2
        The resistance is between the fulcrum and
        the effort applied.
        The effect of the effort applied is always
        muitiplied (d > r)
        
        Class 3
        The effort applied is between the fulcrum
        and the resistance.
        The effect of the effort applied is always
        reduced (d < r)
        
        Class 1
        The fucrum is between the effort applied
        and the resistance.
        The effect of the effort applied can be
        multiplied or reduced
    - - A movable pulley is a set of two pulleys — one is fixed while the other
        can move in a linear direction.
      - A moveable pulley is balanced when it satisfies this equation:
        
        F = R/2
  - - - They consist of two pulleys or wheels that are a certain distance apart.
        
        Their axles are parallel and they rotate simultaneously due to the effect
        of the belt.
        
        Uses:
        
        washing machines and dulls
        
        industrial machines
        
        vehicle engines
    - - It's a system of pulleys, or wheels, with a belt
        formed by more than two wheels.
      - N₄/N₁ = (D₁×D₃) / (D₂×D₄)
    - - Friction drives are made up of two or more wheels that are in contact. The first wheel is called the primary drive wheel. When it moves, it turns or drives the second or output wheel, causing it to move as well.
      - It is expressed by the following equation:
        
        N₁×D₁ = N₂×D₂ ⭢ D₁/D₂ = N₂/N₁
        
        N₁ and N₂ are the velocities of the primary drive wheel and the
        output wheel.
        D₁ and D₂ are the corresponding diameters.
        The ratio D₁ and D₂ is called the gear ratio.
    - - This is a system of more than two gears, connected together as shown in
        the diagram:
      - Each connected geared wheel rotates in the opposite direction to the wheel it's attached to:
        
        N₄/N₁ = (Z₁×Z₃) / (Z₂×Z₄)
    - - These are two cogwheels with parallel axles that are a certain distance apart, they rotate simultaneously by means of a metal chain or a toothed belt stretched over both wheels.
      - The relation between the rotation velocities of the wheels depends on the
        number of teeth on each gear:
        
        N₁ × Z₁ = N₂ × Z₂ → Z₁/Z₂ = N₂/N₁
    - - This is a screw that moves a helical cogwheel that is set perpendicular to the screw
        
        Uses: lap counters, gear reduction systems, musical tuning keys and
        windscreen wipers
      - A worm screw fulfils this equation:
        
        N wheel = (N screw × Z grooves) / Z wheel
    - - Cogwheels are sets of wheels that have teeth called cogs.
        
        Gears can be cyhndrical or conical.
      - The ratio between the rotation veloaues of the wheels depends on the
        number of teeth on each wheel. It's expressed by this equation:
        
        N₁ × Z₁ = N₂ × Z₂ ⭢ Z₁/Z₂ = N₂/N₁
  - - - Rack and pinion system
        
        This uses a pinion that is a small cogwheel, mounted on a rack that is a
        toothed belt or bar.
        
        L= P×Z×N
        
        Z is the number of teeth in the pinion.
        
        L is the velocity of the rack's movement in millimetres per minute
        
        P is the distance between two consecutive teeth in millimetres.
        
        N is the number of rotations per minute of the pinion
      - Nut and bolt system
      - Winch and crank handle
    - - Crankshaft
      - Cam
      - Crank-link-slider
      - Eccentric cam