Abstract: Outlets of a contraction/enlargement exhaust nozzle type are formed in an air bubble-generating plate from which fine air bubbles are generated. The outlets are constituted with outer outlets and inner outlets. The outer outlets are formed along edge portions of the air bubble-generating plate and the inner outlets are formed in the inner portions of the air bubble-generating plate. Each of the outlets has a flow-in portion, a contraction portion, and a flow-out portion which are aligned in a coaxial line and have different diameters, so that each of the outlets are formed in a shape of a contraction/enlargement exhaust nozzle type. A diameter of the flow-out portion is smaller than a diameter of the flow-in portion, but larger than a diameter of the contraction portion. A height of the contraction portion is larger than a height of the flow-out portion, but smaller than a height of the flow-in portion.

Abstract: An air bubble generator for a washing machine has an open box-type case, a porous member, and a plate. The open box-type case has an inlet in the bottom thereof for a passageway of compressed air and space therein for accommodating the compressed air. The porous member provides the accommodated compressed air with passageways. The plate fixedly covers the open box-type case and has through-holes therein. The plate provides air bubbles in the washing water. The porous member has a plurality of compartments symmetrically arranged with respect to each other. The plurality of compartments are arranged along the upper surface of the porous member. Each of the plurality of compartments is spaced apart from the bottom of the case.