1. Field of the Invention
This invention is related to a washing machine, more particularly to a pulsator for a washing machine installed in a washing tub so as to develop a vortex-type water flow.
2. Description of the Prior Art
Generally, a vortex-type washing machine is designed to wash laundry by operating a pulsator in forward and reverse directions, and various kinds of pulsator have been proposed for improvement of washing efficiency.
One example of a pulsator is disclosed in U.S. Pat. No. 5,239,847. The pulsator suggested in U.S. Pat. No. 5,239,847 includes a base and a plurality of blades which project generally radially outwardly along the base. Each blade, which is generally of an S-shape as viewed in plan, includes first and second sides which mutually have different inclinations with respect to the vertical direction. The first side is of a steeper inclination than the second side along a radially outer portion of each blade. As viewed in plan, each blade is generally convex-shaped along its radially outer portion. According to the example, the stirring blades, that is, the plurality of blades, of the pulsator have different slopes and S-shape as viewed in plan to make it possible for the laundry and water to be easily moved radially between an inner area and an outer area of the base during the pulsator being rotated clockwise and counter clockwise.
However, though the laundry and water are smoothly moved from the inner area to the outer area of the base, the pulsator causes the laundry to be tangled and twisted since a heart-type water flow which is developed by the pulsator develops a convergence of the laundry in a central portion of the washing tub.