The question asked this week is: what is a PTO, a power take off shaft and what does it do?
A PTO is a power takeoff shaft commonly found on tractors and used to transfer power to that piece of motor-less equipment. (See also universal joints.) Farm implements that standalone, like augers and other types of grain lifts need power to turn the gears and conveyor mechanism; that power is provided by a tractor's power take off hookup. The shaft is a separate piece of equipment that hooks into the rear of the tractor and then into the implement, in this case the auger. It turns and like a driver shaft as it turns the power turns gears or wheels that power the implement and make it useful for work.
A properly PTO has the shaft covered; if not covered it's an accident waiting to occur and an exposed PTO can be legal grounds for punitive damages should an accident occur. Like fall protection gear the covering on a PTO is intended to shield the workers from injury that sooner or later will befall busy workers. When working around a spinning shaft, assume it's unshielded and stay as far from it as you can. Never, never, never step over a spinning PTO shaft. To know what I'm talking about I've included three images below the fold of the rear of the tractor where the PTO connects, a close up view and a protected (yellow) PTO already hooked between a tractor and piece of farm implement.
If you're wondering what types of injuries can be caused by spinning PTO shafts consider broken legs, quadriplegia, paraplegia, brain damage and if you're lucky death. While good tools make work more efficient they can also maim and kill workers who take them for granted. They are as unforgiving as a woman scorned.