Cyclone type dirt separator and electric vacuum cleaner

Abstract

A cyclone type dirt separator disposed at an intermediate point of an suction tube which connects the suction fitting and the cleaner main body of an electric vacuum cleaner, the dirt separator including: a dirt separating section which causes the suction air to undergo a spiral flow and conducts air from the vicinity of the center of this spiral flow to the cleaner main body, a dirt collection chamber which is attached to the dirt separating section from below and causes the dirt separated from the spiral flow to drop so that the dirt is collected inside the dirt collection chamber, and a recessed portion which is formed in the vicinity of the inside bottom center of the dirt collection chamber so as to be recessed downward.

1 . A cyclone type dirt separator, which is provided at an intermediate point of a suction tube that connects a suction fitting and a cleaner main body of an electric vacuum cleaner and which separates dirt from suction air that contains dirt and is sucked in from the suction fitting, said separator comprising: 
 a dirt separating section which causes the suction air to make a spiral flow and conducts air in a spiral flow to said cleaner main body,    a dirt collection chamber which is mounted on said dirt separating section from below and causes dirt separated from the spiral flow to drop so that dirt is collected in said dirt collection chamber, and    a recessed portion formed in the vicinity of an inside bottom center of said dirt collection chamber so as to be recessed downward.    
   
   
       2 . The cyclone type dirt separator according to  claim 1 , wherein 
 said dirt separating section includes an exhaust tube which is disposed to be substantially in coaxial with a central axis of spiral of the spiral flow, said exhaust tube exhausting air via exhaust openings formed in a circumferential surface of said exhaust tube, and a lower end of said exhaust tube being closed off; and    said dirt collection chamber is in a substantially tubular shape that extends downward and surrounds said exhaust tube.    
   
   
       3 . The cyclone type dirt separator according to  claim 2 , wherein said exhaust tube is provided at a lower end thereof with a substantially flange-form baffling plate which protrudes toward an inside wall of said dirt collection chamber and suppresses a flow of air in upward and downward directions.  
   
   
       4 . The cyclone type dirt separator according to any one of claims  1  through  3 , wherein an inside surface in the vicinity of an opening of said recessed portion and an inside bottom surface of said dirt collection chamber are formed to be unsmoothly continuous to each other.  
   
   
       5 . The cyclone type dirt separator according to  claim 4 , wherein said inside bottom surface of said dirt collection chamber is formed by a curved surface that shows a gradual decrease in diameter in downward direction, and said curved surface and an opening edge of said recessed portion takes an edge-form obtuse angle.  
   
   
       6 . The cyclone type dirt separator according to  claim 1 , wherein said recessed portion is substantially in a shape of a cylinder with a bottom closed.  
   
   
       7 . The cyclone type dirt separator according to  claim 1 , wherein a diameter of an opening of said recessed portion is approximately ½ to ⅓ of a diameter in the vicinity of a center of said dirt collection chamber.  
   
   
       8 . An electric vacuum cleaner comprising: 
 a cleaner main body provided with an electrically driven air blower;    a suction tube with one end thereof connected to a vacuum suction port of said cleaner main body;    a suction fitting attached to a tip end of said suction tube; and    a cyclone type dirt separator which is provided at an intermediate point of said suction tube, said cyclone type dirt separator causing suction air that contains dirt and is sucked in through a suction fitting to undergo a spiral flow, separating dirt from said air, and causing separated dirt to drop into a substantially tubular dirt collection chamber so that the dirt is collected in said dirt collection chamber; wherein    said dirt collection chamber is provided with a recessed portion that is formed in the vicinity of an inside bottom center of said dirt collection chamber and recessed downward.