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mechanism - Coggle Diagram

- - - - F is the force or effort appbed at one end of the bar.
      - r is the distance from R to the fulcrum.
      - d i s the distance from F to the fulcrum
      - R i s the resistance or load which acts at the other end of the bar
    - - There are three types of levers: class l, class 2 and class 3. These
        classilications are based on the relative position of the lever, the effort aplied and the resistence
- - - - This consists of a bolt or threaded bar and a nut that has the same
        intenor diameter as the diameter of the bolt.
        
        If the bolt rotates and the nut can't turn, the nut moves in a linear
        motion along the threaded axle
        
        If the nut rotates in a tixed position, the bolt will move in a linear
        motion.
    - - A crank is a bar attached to an axle that is used to turn it
        
        A winch and crank handle system consists of a drum that rotates and a crank handle that allows to pull or lift obiects The effort needed to turn the winch is less than it would be if we toed to turn it without the crank handle
    - - Cam
        
        This is basically a rotaung obi crt that pushes a follower as it moves We can change the shape and the usable profiles — the outside edge of the piece — that are more or less pointed to produce more complex
        movements.
      - Elecentric cam
        
        This 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 m the follower
        
        Elecentric cam
        
        This consists of a wheel with an off centre rotation axle that doesn't coincide od — —
        with the centre of its circumference follower
  - - - This is composed of a crank and a rod called a connecting rod or link.This rod has articulated Ioints at each end — one is connected to the
        crank and the other to the slider
        
        As the wheel rotates, the crank transmits the rotary motton to the
        t.onnecting rod, which moves in a reciprocating motion. This crank-link-slider system can work in reverse — it can transform
        reciprocating motion or oscillating motion into rotary motion. This device was very important in the development of steam engines.
        
        Uses: internal combustion engmes, windscreen wipers and machine tools
    - - This is a set of connecting rods attached to a jointed axle. Each of the
        ioints of the axle acts as a crank. A crankshaft transforms the rotary motion of an axle into a
        rem procating motion with different connecting rods movmg at different times
        
        lt can also transform the reciprocatmg motion of the rods into a rotary
        motion of the axle.
        
        Uses; combustion engines and sewing machines
    - - This is basically a rotaung obi crt that pushes a follower as it moves. We can change the shape and the usable profiles — the outside edge of the piece — that are more or less pointed to produce more complex movements
        
        Uses; combustion enfpnes (it regulates the automatic opening and
        closing of the valves that let fuel and gases in and out), automatic systems
    - - This 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 m the follower
        
        Uses: sewing machines, windscreen
        wipers
- - - - By traction. The spnng is stretched, in a bed frame for example.
      - By torsion. The spnng is twisted, in a clothes peg for example
      - By compression. The spnng is compressed, in a chair for example.
- - - - The output wheel rotates in the opposite direction of the pnmary wheel
        lf we use more than two wheels, each one rotates tn the opposite direction to the one next to it.
    - - 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.
        
        The rotation of one axle is transmitted to the other through the
        connected pulleys.
        
        The two pulleys, and the two axles, rotate in the same direction Uses: industnal machines, vehicle engines, washing machines and dulls
    - - Cogwheels are sets 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 cyhndncal or conical.can be parallel, perpendicular or oblique
    - - This is a screw that moves a helical cogwheel that is set perpendicular
        to the screw Each time the screw rotates, the gear moves forward as many teeth as
        there are grooves in the screw, usually a small number I, 2 or 3 This is used to reduce velocity as well as functioning as a brake system.
    - - 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 chain transmits the rotary mouon of axle I to axle 2 by means of gears I and 2, and the two gears rotate in the same direction This system transmits greater forces without losing velocity because the chain is attached to the gear teeth so there's no slippage between the chain and the wheel.
    - - This is a system of more than two gears, connected together as shown in
        the diagram
    - - Look at the diagram below. It's a system of pulleys, or wheels, with a belt
        formed by more than two wheels.
        
        The motion of pulley 3 is transmitted to
        pulley 4 by the belt that connects them.
        
        The rotary motion of axle l is
        . transmitted to axle 2 by the belt that connects them
        
        Pulleys 2 and 3 rotate at the same velocity
        
        All the wheels rotate m the same
        direction
- - - - Uses; watch-making, secunty cables and
        brakes
        
        The mechanisms used to reduce velocity are called brakes. There are
        severaltypes
        
        Drum brakes include one or two brake shoes that come into
        contact with the drum.
        
        Band brakes consist of a metal band that puts pressure on a drum
        attached to the axle of the oblect we want to slow down.
        
        Disc brakes consist of pads and a disc anached to the oblect that we
        want to slow down