Clockwork/windup Mechanisms

Clockwork mechanisms are made from mainly these four parts.
- a key, to wind to add energy
- a spiral spring to store the energy
- a set of gears to control the release of energy
- a mechanism that the gears drive the device making it function

Everything that occurs basically is done by the use of energy. To make something move, function or work, energy is used to create this. Enough energy must be used for each individual thing, for example a toy car needs a smaller amount of energy then a real car, where it will travel a longer distance.

A clockwork toy is wound to create energy. "What happens when you wind? If you've ever wound a clockwork toy, you'll know that the key (sometimes it's a little plastic knob called a crown) can be quite stiff and hard to turn. Why is that? When you turn the key, you're tightening a sturdy metal spring, called the mainspring, and storing up energy; the mainspring is the mechanical equivalent of a battery. Clockwork springs are usually thick twists of steel, so tightening them (forcing them to occupy a much smaller space) is actually quite hard work—in both the everyday and the scientific senses of the word. With each turn of the screw, your fingers are doing work (as we say in science): they're moving a force (pushing against the spring's tendency to expand) through a distance—in other words, compressing the spring.

Since you're doing work with your fingers, you're using energy, but that energy doesn't vanish into thin air: it's stored in the spring as potential energy. Tightening the mainspring in a windup toy is like pushing a rollercoaster car up a hill. Just as you can get the energy in a rollercoaster car back by letting it roll down the hill, so you can get the energy back from a mainspring by releasing it to drive a clockwork mechanism—the potential energy is converted into kinetic energy (as well as heat and sound energy) in the whirring gears.

If you want a clockwork device to entertain you (or do something useful) for a while, you need to give it plenty of energy. Windup clocks and watches are designed to have springs that will store enough energy to keep the mechanism working for a day or more. Clockwork toys aren't anything like as well made (or as impressive) and if you get more than a minute or two's entertainment for your thirty seconds or so of winding you're doing well. Generally, more interesting clockwork devices that run for longer have bigger and sturdier springs capable of storing much more energy. The size and tension of the spring control how much energy it will hold. The harder a spring is to turn and the longer you wind it, the more energy it will store." - www.explainthatstuff.com/how-clockwork-works.html

The gears that control the release of energy are essentially clogs (wheels with teeth that mesh together) - gears are used to make a wheel go faster, with less force - or to make it go more slowly, with more force. Both of these ways are used within a clocks mechanisms as the speed of the two hands (second, minute and hour) move at different speeds - second hand at one speed, minute at 1/60 of the second speed and the hour hand at 1/3600. Clockwork provides rotational power, so is centralised by one point and the hands run around in a continuous radius of this point. Other movements can be done by using a cam or a crank like in the photos here. (clockwise)