I’m thinking of things like waterwheels, windmills, millstones, etc- these systems would presumably have a lot of force running through them, such that stopping them for maintenance or replacement would seem difficult to do and maybe even damage the system. So what kind of mechanisms back in the day did people put in place to stop energy from moving through the machine at a given point? How do you successfully get two gears that are actively engaged to be safely uncoupled, for lack of a better word?
In: Engineering
You stop the source of energy that is powering the machine. It’s the same way we stop machines now.
For example, a water wheel is in a sluice, a channel where the water flows. The amount of water flowing into that channel is controlled by a control gate to keep the wheel operating at its ideal speed. That control gate can be shut entirely to stop all of the water, meaning that the wheel will no longer be pushed by water and will come to a stop. For a traditional windmill, or indeed a modern wind turbine, you can control the pitch of the blades so that they become parallel to the wind and stop forcing the windmill to turn.
So, in short, you turn off the power and you wait until the machine stops.
Latest Answers