Please enable JavaScript.

Coggle requires JavaScript to display documents.

MECHANISMS, image, image, image, image, image, image, image, image, image,…

- - - - the mechanisms used to reduce velociy are called brakes
        
        disc brakes
        
        disc drum
        
        band brakes
  - - - they work in different ways
        
        by compression
        
        by traction
        
        by torsion
- - - - is a rigid bar that is supported by a fulcrum
        
        F- effort
        
        R- load
        
        d- the distance from F to the fulcrum
        
        r- the distance from R to the fulcrum
        
        Law of the lever--- F.d=R.r
      - three types of levers
        
        class 1
        
        the fulcrum is between the effort applied and the load
        
        class 2
        
        The load is between the fulcrum and the effort applied
        
        class 3
        
        The eefort applied is between the fulcrum and the load
    - - fixed pulleys
        
        is a wheel that has a groove around it into which a rope chain or belt fits
        
        it is balanced when the effort is equal to the load ( F=R)
      - movable pulley
        
        is a set of two pulleys ( one fixed while the other can move in a lineal directions)
        
        It is balanced when F= R/2
      - compound pulley
        
        is a system of fixed and movable pulleys
  - - - are made up of two or more wheels that are in contact
        
        the first whell is called primary wheel. when it moves it drives the output wheel, causing it to movee as well. the output wheel will move in the opposite direction to the one next to it
        
        the ratio between therotation velocity of the wheels or pulleys depends on the relative size of the wheels
        
        N1.D1=N2.D2-> D1/D2=N2/N1
        
        N1 and N2 are the velocities of each wheel
        
        D1 and D2 are the diameters of each wheel
    - - they are two pulleys or wheels that are a certain distance apart
        
        the rotation of an axle is transmitted to the other through the connected pulley
        
        the two wheels rotate in the same direction
    - - Cogwheels are a set of wheels that have teeth called cogs
        
        the cogs fit into the spaces between the cogs of another wheel, so that one wheel moves the other
        
        Gears can be cylindrical or conical
        
        The ratiop between the velocities of the wheels depends on the number of teeth on each wheel
        
        N1.Z1=N2.Z2->Z1/Z2=N2/N1
        
        N1 and N2 are the velocities of each wheel
        
        Z1 and Z2 are the number of teeth of each wheel
    - - This is a screw that moves a helical cogwheel that is perpendicular to the screw
        
        each time the screw rotates, the gear moves forward as many teeth as there are grooves in the screw
        
        A worm screw fulfils this equation
        
        Nwheel= (Nscrew. Zgrooves)/ Zwheel
        
        Nwheel and Nscrew are the velocities of the wheel and the screw
        
        Zgrooves is the number of grooves of the screw and Zwheel is the number of teeth of the whell.
    - - These are two cogwheels with parallel axles that are a certain distance apart. They rotate simultaneously
        
        This system transmits graeter forces without losing velocity.
        
        To calculate the ratio between the rotation velocity of the drive wheel and the driven wheel is used the same equation as for gear mechanisms
    - - This is a system of more than two gears
        
        Each connected wheel turns in the opposite direction to the wheel it's attached to.
        
        thye gear ratio between the drive wheel and the driven wheel depends on the number of geared teeth in the system
        
        N4/N1=Z1.Z3/Z2.Z4
        
        N1 and N4 are the velocities of the drive wheel and the driven wheel
        Z1,Z2,Z3 and Z4 are the number of teeth of the wheel.
    - - It's a system of pulleys or wheels with a belt formed by more than two wheels.
        
        The gear ratio between the drive pulley abd the driven pulley depends on the relative size of the pulley system
        
        N4/N1=D1.D3/D2.D4
        
        N4 and N1 are the velocities of the dive wheel and the driven wheel
        D1,D2,D3 and D4 are the diameters of each wheel.
    - - When the drive wheel is bigger than the driven wheel, the driven wheel turns faster
        
        When they have the same size they turn at the same velocity
        
        When the drive wheel is samaller than the driven wheel, the driven wheel turns slower
- - - - The ratio between the number of rotation of the pinion and the velocity of the movement of the rack is expressed by this equation
        
        L= P.Z.N
        
        L is the number of the rack's movement in milimeters per minute. P is the distance between two consecutive teeth in milimeters. Z is the number of teeth in the pinion and N is the number of rotations per minute of the pinion
    - - it consists on a bolt or threaded bar and a nut that has the same interior diameter of the bolt
        
        if the bolt rotates and the nut can't turn, the nut will move in a linear motion.
        
        if the nut rotates in a fixed position, the bolt will move in a linear motion.
    - - Is a system that consists of a drum that rotates and a crank handle that allows to pull or lift objects.
        
        The longer the crank handle, the less effort is needed to lift the load
        
        F.d=R.r
        
        F is the force applied, R is the resistance. r is the radius between r and d, the lenght of the crank handle
  - - - is composed of a crank and a rod called a connecting road or link
        
        the road has articulated joints at each end
        
        as the wheel rotates, the crank transmits the rotary motion to the connecting rod, which moves on a reciprocating motion
    - - this is a set of connecting rods attached to a jointed axle.
        
        a crankshaft transforms the rotary motion of an axle into a reciprocating motion.
    - - this is basically a rotating object that pushes a follower as it moves
        
        it transforms rotary motion into reciprocating motion in the follower or bar
    - - it consists of a wheel with an off-centre rotation axle that doesn't coincide with the centre of its circumference
        
        it transforms the rotary motion of the wheel into reciprocating motion in the follower