Patent ID: 7947099
Filing Date: 2011-05-24
Classification: A47L,B01D

Abstract:
1. A dust suction device for surface working tools, comprising: two filters; an air inlet chamber with an air inlet for the two filters; a turbine having an inlet and an outlet; an outlet chamber in communication with the outlet of the turbine; a depression chamber in communication with the inlet of the turbine; two intermediate chambers separated from each other being interposed between said inlet chamber and said depression chamber and separately communicating with said inlet chamber through a respective one of said filters; and a valve system for controlling the flow of air through said filters, said valve system comprising for each of the two intermediate chambers a first valve for controlling the communication between the intermediate chamber and the depression chamber so that an air flow from the inlet chamber passes through the respective filter during a suction step and a second valve for controlling the communication between the outlet chamber and the same intermediate chamber so that an air flow from the outlet chamber passes through said filter during a filter cleaning step, wherein said filters are separate planar filters laterally arranged with respect to each other and said first and second valves of each intermediate chamber are arranged to open and close alternately respective communication holes of the intermediate chamber which are laterally adjacent to each other and both faced to the filter associated with said intermediate chamber so that said air flows have parallel rectilinear paths between said communication holes and said filter.