Abstract: A porous transport layer is disclosed. The porous transport layer includes a base layer containing a titanium family element, a first coating layer disposed on one surface of the base layer and containing iridium (Ir), and a second coating layer disposed on the other surface of the base layer, and containing at least one of platinum (Pt), gold (Au), and silver (Ag), and a method for preparing the same.

Abstract: Disclosed is a safety device for a power brush of a vacuum cleaner which has a simple structure and can automatically cut off an electric source supplied to the driving motor of the power brush. A cylindrical air duct is vertically provided on the brush. The air duct is attached to the body of the cleaner. A negative pressure generated by a sucking force generated by the rotation of the driving motor in the body of the cleaner acts on the air duct. An air valve moves inward by the negative pressure in the air duct. At a first end of a rod, the air valve is mounted and at a second end facing the first end, a spring for applying a rotating force to move the air valve to an external direction, is provided. The rod is movably supported by a moving shaft provided near the outer periphery of the air duct. A switch is provided at the second end side of the rod having the spring.

Abstract: Disclosed is a power brush for a vacuum cleaner by which dust is easily sucked into the vacuum cleaner with reduced noise and which can be easily manufactured. A brush body sucks dust by making contact with a floor. The brush body is provided at an end of a rigid wand which is connected to a vacuum cleaner body. A bottom portion of the brush body is open so that an air is introduced therein. A rotatable roller is provided at the bottom portion of the brush body. A pair of driving fans for generating a rotational force to rotate the rotatable roller are provided at both sides of the rotatable roller. The driving fans are driven by a dustless air which is introduced into the brush body through the air inlet holes which are formed at the front of the brush body.