Thread: pedal and treadle

What's the difference between "pedal" and "treadle"? In a truck ,one has the treadle valve (brakes)which is, in fact, our "pedal de frenos".

I thought the treadle had to be continually pressed, like in one of those old sewing machines that you had to keep pushing to make it move, while a pedal can be pushed only once.

...steps on the brake pedal, or treadle valve, this allows air from the storage...
In fact, the brake pedal actuates the treadle valve in the brake system.