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MECHANISMS:devices that transmit and convert forces and motion from a …

- - - - cogs: fit into the spaces between the cogs of another wheel
        
        transmit a rotary motion between the two connected axles, can be
        
        perpendicular
        
        oblique
        
        parallel
      - Gears can be
        
        cylindrical
        
        conical.
      - The ratio between the rotation veloaues of the wheels depends on the number of teeth on each wheel.
        
        equation:N1·Z1=N2·Z2
        
        N are the velocities of the corresponding wheel
        
        Z are the number of teeth
      - uses:
        
        bicycles
        
        motorbikes
        
        .
        
        engines
        
        motors
        
        three-wheeled vehicles
        
        industnal machinery
    - - equation: Nwheel= (Nscrew · Zgrooves)/Zwheel
        
        Zgrooves is the number of grooves of the screw
        
        Nwheel and Nscrew are the velocities of the wheel and of the screw
        
        Zwheel s the number of teeth of the wheel
      - uses:
        
        windscreen wipers
        
        gear reduction systems
        
        lap counters
    - - axles: are parallel and they rotate simultaneously
        
        rotation of one axle is transmitted to the other through the
        connected pulleys.
      - pulleys and axles rotate in the same direction
      - uses:
        
        vehicle engines
        
        washing machines
        
        industrial machines
        
        drills
    - - The gear ratio between the drive wheel (I) and the dnven wheel (4) depends on the number of geared teeth
        
        equation: N(4)/N(1)=[Z(1)·Z(3)]:[Z(2)·Z(4)]
        
        N(1) and N(2) are the velocities of the dnve wheel and the dnven wheel.
        
        Z are the number of teeth on the wheels.
      - uses:
        
        vehicle gearboxes
        
        robotics
        
        machine tools
    - - 1st wheel: primary drive wheel when it moves, it turns or drives the second or output wheel,
      - the ratio between the rotation velocity of the wheels or pulleys depends on the relative size of the wheels.
        
        equation: N1·D1=N2·D2
        
        N are the velocities of the primary drive wheel and the
        output wheel
        
        D are the corresponding diameters
    - - N4/ N1 = (D1·D3)/(D2·D4)
      - rotary motion of axle is transmited to axle 2 by the belt that connects them
        
        pulleys 3 and 2 rotate at the same velocity
        
        motion of pulley 3 is transmitted to pulley 4 by the belt that connects them
        
        all the wheels rotate in the same direction
      - Uses
        
        machine tools
        
        drills
    - - relation between the rotation veloaties of the wheels depends on the number of teeth
        
        equation: N(1)·Z(1)=N(2)·Z(2)
        
        N are the velocities of the corresponding wheels
        
        Z are the number of teeth
      - uses:
        
        motorbikes
        
        bicycles
        
        industrial machinery
  - - - RACK AND PONION SYSTEM
        
        uses pinion that is a small cogwheel, mounted on a rack that is a toothed belt or bar
        
        L= Px Z xN
        
        uses
        
        crorkscrews
        
        vehicle steerig
        
        bench drills
      - NUT AND BOLT SYSTEM
        
        a bolt or threaded bar and a nut that has the same interior diameter as the diameter of the bolt.
        
        uses
        
        taps
        
        screw tops for bottles
        
        presses
      - WINCH AND CRANK HANDLE
        
        A crank is a bar attached to an axle that is used to turn it
        
        F x d= R x r
        
        uses
        
        coffee grinders,
        
        cranes
        
        roller blinds
    - - CRANKSHALT
        
        set of connecting rods attached to a jointed axle. Each of the
        ioints of the axle acts as a crank.
        
        uses
        
        combustion engines
        
        sewing machines
      - CAM
        
        This is basically a rotaung object that pushes a follower as it moves
        
        uses
        
        combustion engines
      - CRANK-LINK-SLIDER
        
        composed of a crank and a rod called a connecting rod or link
        
        uses
        
        windscreen wipers
        
        internal combustion engines
        
        machine tools
      - ECCENTRIC CAM
        
        This consists of a wheel with an off centre rotation axle that doesn't coincide with the centre of its circumference
        
        uses
        
        sewing machines
        
        windscreen wapes
  - - - LENGUAGE
        
        R is the resistance or load which acts at the other end of the bar
        
        d is the distance from F to the fulcrum
        
        F is the force or effort appbed at one end of the bar.
        
        r is the distance from R to the fulcrum
      - (law of the lever) balanced lever equation:
        
        F·d = R·r
      - TYPES
        
        class 2
        
        resistance is between the fulcrum and the effort applied.
        
        effect of the effort applied is always muitiplied (d > r)
        
        class 3
        
        effort applied is between the fulcrum and the resistance.
        
        effect of the effort applied is always reduced (d < r)
        
        class 1
        
        fulcrum is between the effort applied and the resistance.
        
        effect of the effort applied can be
        
        multiplied
        
        reduced
    - - MOVABLE:has two pulleys:one is fixed and the other can move in a linear
        direction
        
        is balanced when it satisfies this equation
        
        F=R/2
      - COMPOUND:set of fixed and moveable pulleys called block and tackle
        
        is a system of fixed and moveable pulleys, often called block and
        tackle.
        
        Uses:
        
        lift
        
        cranes
      - FIXED:A fixed pulley is a wheel that has agroove for a rope, to go roundlt.It rotates around an axle that ls fixed toan immobile surface.
        
        is balanced when the effort F is equal to the resistance of the load, R
        
        F=R
        
        Uses:
        
        gym equipment
        
        wells
  - - - ways
        
        traction
        
        torsion
        
        compression
      - Uses
    - - fixed connection
      - movable connections
      - clutches
    - - types
        
        band brakes
        
        drum brakes
        
        disc brakes
    - - bushings
      - bearings