hereinafter , an embodiment of an electric vacuum cleaner according to the present invention will be described with reference to the drawings . an electric vacuum cleaner 10 shown in fig1 includes a vacuum cleaner body 20 . the front portion of the vacuum cleaner body 20 is provided with a hose connection port 21 . a dust collection hose 12 has one end detachably connected to the hose connection port 21 and has the other end provided with a hand operation unit 13 . an extension wand 14 is detachably connected to the hand operation unit 13 . a suction port 15 is detachably connected to the leading end portion of the extension wand 14 . the hand operation unit 13 is provided with an operation part 13 a including a plurality of operation switches s . the vacuum cleaner body 20 includes a body case 30 , a dust collection container 50 detachably mounted on the body case 30 and a cover body 40 having the back portion connected to the body case 30 by a hinge so as to be openable and closable in the up and down direction , as illustrated in fig2 . in addition , an electric fan 33 ( refer to fig3 ) is built in a back portion 30 a of the body case 30 , and a cord reel 34 is disposed below the electric fan 33 . a plate - like mounting section 35 is provided in front of the body case 30 ( on the left side in fig3 ). the dust collection container 50 is detachably mounted on the mounting section 35 . the cover body 40 and the mounting section 35 enclose the dust collection container 50 , so as to fasten the dust collection container 50 when the cover body 40 is closed . the cover body 40 is provided with a tube portion 22 as shown in fig3 . the leading end of the tube portion 22 is the hose connection port 21 and the back end of the tube portion 22 is a connection opening 23 . a front opening ( not shown ) is formed in a front wall portion 31 ( reference to fig2 ) of the back portion 30 a . the front opening communicates with a suction opening 33 a of the electric fan 33 via a communication air path ( not shown ). the communication air path opposed to the front opening is provided with a dust removing device 90 . the dust removing device 90 includes a reciprocating body ( not shown ) for reciprocating in the width direction of the body case 30 ( in the direction orthogonal to the page space of fig3 ) and a projection 91 provided in the reciprocating body . the projection 91 shallowly engages with a top portion of a pleat of an after - mentioned pleated filter body 100 , and the projection 91 moves over the top portions of the pleat by the reciprocating of the reciprocating body . the dust removing device 90 thereby removes the dust adhering to the pleated filter body 100 by vibrating the pleated filter body 100 . the reciprocating body reciprocates for a predetermined time every time the driving of the electric fan 33 is stopped . as shown in fig4 , 5 , the dust collection container 50 includes a round air path section 51 formed on the upper portion thereof , a dust collection section ( a first dust collection section ) 60 formed below the round air path section 51 , a negative pressure room 70 formed at the back of the dust collection section 60 , and a bottom pad 80 . the round air path portion 51 includes a dust separation section ( a first dust separation device ) 52 provided in the central portion thereof and a circular arc round air path 53 provided around the dust separation section 52 , as shown in fig6 . a leading end opening 54 of the leading end of the round air path 53 is connected to the connection opening 23 of the tube portion 22 of the cover body 40 as shown in fig3 . the round air path 53 communicates into the dust collection section 60 via a back end opening 55 . moreover , the round air path 53 includes an opening 57 which is formed in the bottom portion in the middle of the round air path 53 and communicates with the negative pressure room 70 . a net filter f 2 is stretched to the opening 57 . the dust separation section 52 includes a frame ( not show ) having an almost cylindrical shape and a net filter f 1 stretched to the frame . the bottom portion of the dust separation section 52 opens , such that the dust separation section 52 communicates with the negative pressure room 70 via an opening 56 . a dividing wall 61 provided in the back portion of the dust collection section 60 includes an opening 62 which communicates with the negative pressure room 70 . a lower portion wall 61 a of the dividing wall 61 includes a communication hole ( communication opening ) 63 positioned in an upper portion of a fine dust collection section 74 . more particularly , the communication hole 63 is formed below the opening 62 . a net filter ( the first dust separation device ) f 3 is stretched to the opening 62 . a frame 71 for detachably installing a pleated filter body ( a second dust separation device ) 100 is integrally formed in the back portion of the negative pressure room 70 ( on the right side in fig5 ). a back end opening 72 of the frame 71 is connected to the front opening ( not shown ) of the body case 30 shown in fig3 . a lower portion back wall 73 is formed in the lower portion of the frame 71 . the fine dust collection section ( the second dust collection section ) 74 includes a space surrounded by the lower portion back wall 73 , the lower portion wall 61 a of the dividing wall ( partition wall ) 61 of the dust collection section 60 and the bottom pad 80 . the fine dust collection section 74 communicates with the dust collection section 60 via the communication hole 63 of the dividing wall 61 . in addition , as shown in fig7 , an introduction opening 75 is formed between a lower frame wall 71 a of the frame 71 and the lower portion wall 61 a of the dividing wall 61 as shown in fig7 . in addition , one end portion ( upper portion in fig7 ) of an opening and closing plate ( opening and closing member ) 76 for closing the introduction opening 75 is supported by the lower portion of the dividing wall 61 of the dust collection section 60 . the opening and closing plate 76 is rotatable upon one end portion of the opening and closing plate 76 . the opening and closing plate 76 closes the communication hole 63 of the dividing wall 61 by its own weight and opens the introduction opening 75 of the fine dust collection section 74 , when the electric fan 33 is not driven . the opening plane of the communication hole 63 is configured such that the opening and closing plate 76 rotates to close the introduction opening 75 ( refer to fig9 ), if the pressure in the negative pressure room 70 becomes negative by the driving of the electric fan 33 . the bottom pad 80 is a rotatable in the clockwise direction about an axis 81 illustrated in fig3 . if a button b provided in a holding portion 58 of the dust collection container 50 is pressed , the bottom portion of the dust collection section 60 and the bottom portion of the fine dust collection section 74 are opened . accordingly , the dust accumulated in the dust collection section 60 and the fine dust collection section 74 can be disposed . next , the operation of the electric vacuum cleaner having the above structure will be explained . at first , as shown in fig2 , the dust collection container 50 is mounted on the mounting section 35 of the body case 30 , and the cover body 40 is closed . as shown in fig1 , one end of the dust collection hose 21 is connected to the hose connection port 21 of the cover body 40 . in this state , as illustrated in fig3 , 7 , the opening and closing plate 76 of the dust collection container 50 closes the communication hole 63 of the dividing wall 61 by its own weight . if the switch s of the operation part 13 a is operated , the electric fan 33 is driven . by the driving of the electric fan 33 , air is sucked from the suction opening 33 a of the electric fan 33 , creating a negative pressure in the negative pressure room 70 of the dust collection container 50 . thereby , the opening and closing plate 76 rotates by this negative pressure so as to close the introduction opening 75 as shown in fig8 , 9 . if the introduction opening 75 is closed by the opening and closing plate 76 , the fine dust accumulated in the fine dust collection section 74 is prevented from rising to adhere to the pleated filter body 100 . in addition , since the communication hole 63 of the dividing wall 61 of the dust collection container 50 is formed in the upper portion of the fine dust collection section 74 , the air flows as illustrated by the arrows in fig7 , 9 when the opening and closing plate 76 rotates to close the introduction opening 75 . accordingly , the dust accumulated in the fine dust collection section 74 is not raised by this air . as described above , the opening and closing plate 76 rotates by the driving of the electric fan 33 so as to close the introduction opening 75 ; thus , the structure of the opening and closing plate 76 is simplified . on the other hand , a negative pressure is created in the dust collection section 60 and the round air path 53 by the negative pressure of the negative pressure room 70 of the dust collection container 50 . this negative pressure acts on the tube portion 22 , the dust collection hose 12 , the extension wand 14 and the suction port 15 , so as to vacuum the dust together with air from the suction port 15 . the vacuumed dust and air are sucked into the hose connection port 21 of the cover body 40 via the extension wand 14 and the dust collection hose 12 . the dust and air sucked into the hose connection port 21 is sucked into the dust collection section 60 through the round air path 53 of the dust collection container 50 . a part of the air is separated from the dust by the round air path 53 , and the separated air is sucked to the negative pressure room 70 through the net filters f 1 , f 2 . the dust and air sucked into the dust collection section 60 are separated , and the separated air is sucked to the negative pressure room 70 through the net filter f 3 and also the dust is collected in the dust collection section 60 . the air sucked to the negative pressure room 70 is sucked to the suction opening 33 a of the electric fan 33 via the pleated filter body 100 or the like . the sucked air is discharged from a discharging port 33 b of the electric fan 33 , and is discharged outside from a discharging port ( not shown ) of the body case 30 . if the driving of electric fan 33 is stopped , the sucking of dust and air from the suction port 15 is stopped . the degree of vacuum of the negative pressure room 70 of the dust collection container 50 is thereby increased to atmospheric pressure . the opening and closing plate 76 of the dust collection container 50 rotates by its own weight , so as to close the communication hole 63 of the dividing wall 61 as shown in fig3 , 7 , opening the introduction opening 75 of the fine dust collection section 74 . on the other hand , the reciprocating body ( not shown ) of the dust removing device 90 reciprocates for a predetermined time by stopping the driving of the electric fan 33 ; thus , the dust adhering to the pleated filter body 100 is removed . the dust removed from the pleated filter body 100 is disposed into the fine dust collection section 74 because the introduction opening 75 is opened as shown in fig7 . in order to dispose of the dust accumulated in the dust collection section 60 and the fine dust collection section 74 of the dust collection container 50 , the dust collection container 50 is removed from the body case 30 , and the bottom pad 80 rotates in the clockwise direction about the axis 81 to open the bottom portion of the dust collection section 60 and the fine dust collection section 74 . accordingly , the dust accumulated in the dust collection section 60 and the fine dust collection section 74 is disposed . according to one embodiment of the present invention , the introduction opening of the second dust collection section can be opened and closed by means of a simple structure ; thus , the re - adhesion of dust can be prevented . the present application is based on and claims priority from japanese application no . 2006 - 99862 filed on mar . 31 , 2006 , the disclosure of which is hereby incorporated by reference herein in its entirety . although the present invention has been described in terms of an exemplary embodiment , it is not limited thereto . it should be appreciated that variations may be made in the embodiment described by persons skilled in the art without departing from the scope of the present invention as defined by the following claims . in addition , the number , position , shape , or the like of the components are not limited to the above embodiment , and can be changed to the number , position , shape or the like of components preferable for conducting the present invention . moreover , no element or component in the present disclosure is intended to be dedicated to the public regardless of whether the element or component is explicitly recited in the following claims .
an electric vacuum cleaner includes a first dust separation device configured to separate sucked dust , a first dust collection section for collecting the separated dust , a second dust separation device configured to separate the dust , a dust removing device configured to remove the dust adhering to the second dust separation device , a second dust collection section for accumulating the removed dust , a partition wall for zoning the first dust collection section and the second dust collection section and an introduction opening for introducing the removed dust into the second dust collection section ; the partition wall includes a communication opening for communicating the first dust collection section to the second dust collection section and an opening and closing member for closing either of the introduction opening or the communication opening and switching the closing to the other by rotating , and the opening and closing member closes the introduction opening with a negative pressure by an electric fan and closes the communication opening by its own weight when the electric fan is not driven .