Treadles and Water Motors 262. Definition of Motor. A motor is a device for utilizing the power stored in gasoline, electricity or elevated water for doing work. The structure of the motor depends upon the source of its power, as does its name. Besides the motor, there is a treadle, or foot-power motor, used in the home. 263. The Treadle. The treadle is a small platform, which rocks on two pivots. As the treadle is rocked, it moves a rod attached to its outer edge, upward and downward. This rod is then attached to a wheel a short distance from the hub, so that the upward and downward motion of the shaft turns the wheel. When a belt is attached to the wheel, it will run a sewing machine or other small device. 264. Water Motors. Water motors are commonly used in the household on washing machines and pumps (Figs. 149 265. Selecting a Water Motor. Before purchasing any device to be operated by a water motor, ascertain how much water pressure you have available. Under enough pressure, the water from a faucet will give power enough to a small-sized water motor to run a washing machine, sewing machine or small feed grinders. These motors are usually less than one-half horse power. 266. Two Types of Water Motors. One type of water motor is made up of a piston and valves in a cylinder (Fig. 150). The water pushes the piston to a certain point when a valve opens and lets out the water. The piston then moves backward until it automatically opens another valve, letting in more water, which, in turn, pushes the piston forward and again to the point where the first valve opens. The motion of the piston must be strong enough to do the work. About twenty-five pounds of water pressure is required in moving the piston forward when attached to a machine which might be operated by hand by a woman. Another type of water motor consists of cups or fans on the rim of a wheel. As the water flows over the wheel, it pushes it around, thus giving it power to do work provided there is enough pressure behind the water (Fig. 150-a). |