Electric vacuum cleaner provided with a dust separation section for separating sucked dust and dust collecting section for collecting the dust

A dust separation section is provided at a suction air passage between a suction opening of a vacuum cleaner main body and an intake opening of a motor fan to separate dust sucked from the suction opening with air and a dust collection section provided at the suction air passage for collecting the dust separated from the air from the dust separation section. Moreover, the dust separation section of the electric vacuum cleaner has a dust guiding space adapted to inflow the dust sucked from the suction opening from one end of the dust guiding space and for guiding the dust from an other end of the dust guiding space to the dust collection section, through a dust strike section, by an inertia force, and an air guiding air passage is provided to guide air from a midstream of the dust guiding space to the intake opening of the motor fan without passing through the dust collection section.

This application is a U.S. National Phase Application under 35 USC 371 of International Application PCT/JP2003/003253 filed Mar. 18, 2003.

TECHNICAL FIELD

The present invention relates to an electric vacuum cleaner provided with a dust separation section for separating sucked dust and a dust collection section for collecting the dust.

BACKGROUND ART

Heretofore, there have been known an electric vacuum cleaner provided with a cyclone system as shown inFIG. 34(for example, see Japanese Patent Laid Open No. 2001-104223).

The electric vacuum cleaner is provided with a dust cup1whose upper part is opened and a motor fan2for causing inside of the dust cup1to be negatively pressured or the like. An intake vent3is formed at a peripheral wall1A of the dust cup1and the intake vent3is communicated with a suction opening body4for sucking a dust through an intake passage5.

The dust sucked from the suction opening body4is sucked inside of the dust cup1from the intake vent3of the dust cup1through the intake passage5. A spiral flow is generated inside of the dust cup1, thereby the dust and air are separated, and only the air is sucked from the upper part opening of the dust cup1by the motor fan2and is exhausted outside.

By the way, in such electric vacuum cleaner, the air sucked upwardly toward the intake passage5changes direction at 90 degrees and enters inside of the dust cup1from the intake vent3, and at this point, the air is turned into the spiral flow and adapted to be revolved along the peripheral wall1A of the dust cup1and then only the air is sucked upwardly toward the motor fan2. Like so, because the direction of the air is changed twice, its loss of air passage is large (i.e., loss in an amount of air passing through is large), and furthermore, because the air is sucked to the motor fan2after revolving inside of the dust cup1, its loss of air passage becomes exceedingly large, causing a problem that a performance of the motor fan deteriorates.

Additionally, there have been also known such a conventional electric vacuum cleaner that allows the dust which is sucked inside of a dust collection case to be separated by hitting the dust to a hyperbolic wall section as disclosed in Japanese Patent Publication No. 61-22563 for example.

In this electric vacuum cleaner, there is provided a cylindrical dust collection case that extends toward upward and downward direction, and a main body case which is loaded on a top edge of the dust collection case. Inside of the main body, the motor fan is built-in for causing a sucking-negative pressure to operate in the dust collection case.

Furthermore, in a bottom of the dust collection case, a longitudinal wall is provided which projects upwardly from a part proximity to an edge of a bottom wall. At a center of the longitudinal wall, there is formed a helical groove disengaging in an upward direction. Also, at the longitudinal wall, a partition wall is continuously built to divide inside of the dust collection case into lower side's first dust collection room and upper side's second dust collection room by marking off inside of the dust collection case into an upper part and a lower part.

The partition wall has a bottom plate whose edge has a U-shape and is also provided with a projecting portion that engages to a lower end of the helical groove of the longitudinal wall, an internal side wall which is continuously built to both sides edge of the helical groove respectively and is also built projective toward an upward direction at a part proximity to side edge in a U-shape along the side edge of the bottom plate, and a hyperbolic external side wall which is formed with a hyperbolic shape at an edge of the bottom plate corresponding to the U-shaped part of the internal wall and is also positioned opposite to the longitudinal wall. Further, at the hyperbolic part of the internal side wall, there is formed an opening, and between the internal side wall and the hyperbolic external side wall, there is formed a hyperbolic air passage.

Also, a ventilation opening is formed between the hyperbolic external wall and the longitudinal wall, and a mesh shaped filter is loaded to the ventilation opening. In addition, the hyperbolic external side wall is provided as a primary filter at the opposite side of the side wall's longitudinal wall in such a manner as to extend in upward and downward direction and roughly concentric to the dust collection case, and a hose opening is provided at the dust collection case facing the hyperbolic external side wall. Moreover, in this electric vacuum cleaner, an upper end of the dust collection case is closed with a filter holding plate, and at the filter holding plate, there is formed a tube section connected to an upper part of a hyperbolic internal side wall, and a main filter is loaded to a lower end of the tube section.

In such an electric vacuum cleaner as mentioned, when the motor fan is activated, the motor fan's sucking negative pressure acts upon the first dust collection room through the main filter, the second dust collection room and the mesh shaped filter, and the intake negative pressure that acts upon the first dust collection room acts upon the suction opening body which is not shown in the figure through dust collection hose and extension pipe for example that are connected to a hose connection opening.

By the aforementioned method, the dust sucked from the suction opening body is sucked to the first dust collection room with the air from the hose opening through the dust collection hose. And, some of the sucked dust and the air hit hyperbolic external side wall and then, flow along the hyperbolic external wall toward a side of the mesh shape filter. On this occasion, relatively heavy dust is adapted to be dropped and deposited on a bottom of a rough dust room, and remained dust's light cotton dust, for example, is captured by the mesh shaped filter when the air percolates the mesh shaped filter.

Furthermore, microscopic dust even smaller than the cotton dust passes through the mesh shaped filter together with the air. Such microscopic dust is captured through the main filter when the air passes through the main filter, and is deposited on a bottom of the second dust collection room.

But, in fact, because the air that hits the hyperbolic external side wall flows toward the side of the mesh shaped filter along the hyperbolic external side wall, the dust flows toward the side of the mesh shape filter along the hyperbolic external side wall together with the air.

In addition, relatively large and heavy dust is adapted to be deposited at a lower part of the mesh shape filter. Consequently, if an amount of dust deposited increases, then the amount of deposited dust increases at the side of the mesh shaped filter before the dust is captured in entire rough dust room, causing a tendency that the filter clogs at an early stage.

Also, because some of the air hits the hyperbolic external wall flows to the lower part along the hyperbolic external wall, the dust that hits the hyperbolic wall and drops to the lower part flows to the side of the longitudinal wall together with the air that flows to the lower part, causing some of the dust deposited on the side of the longitudinal wall to fly up, so there is a tendency that the dust flew up attaches to the mesh shaped filter and the mesh shaped filter clogs at an early stage.

The reason that these phenomena occurs is because all the air that are sucked from the hose connection opening are adapted to flow only to the first dust collection room which is to capture the dust, then adapted to flow to side of the second dust collection room through the ventilation openings' mesh shape filter which opens at the first collection room.

In addition, there is also a conventional electric vacuum cleaner in a type that loads a paper package as a paper filter at the dust collection room. In this common electric vacuum cleaner, since the intake vent, the paper package and the motor fan are arranged linearly, the loss of air passage is relatively small. However, in such common electric vacuum cleaner there is a problem that an amount of air decreases significantly once the dust accumulates in the paper package.

It is an object of the invention to provide an electric vacuum cleaner which is capable of reducing the loss of air passage, and furthermore, in which the amount of air does not decrease at the early stage even if the dust accumulates.

DISCLOSURE OF INVENTION

An electric vacuum cleaner of the present invention has a dust separation section provided at a suction air passage which is leading from a suction opening of a vacuum cleaner main body to an intake opening of a motor fan to separate dust sucked from the suction opening with air and a dust collection section provided at the suction air passage for collecting the dust separated from the air at the dust separation section.

In addition, the dust separation section has a dust guiding space adapted to inflow the dust sucked from the suction opening from an one end and for guiding the dust which flows in from an other end to the dust collection section by an inertia force. Also, an air guiding air passage is provided in the electric vacuum cleaner of the present invention to be communicated with a midstream of the dust guiding duct and is communicated with the intake opening of the motor fan without passing through the dust collection section.

According to the structure mentioned above, since the dust sucked with the air goes straight by inertia and is collected, and the air is sucked by the motor fan through the opening, the air and the dust are separated without generating the spiral flow, therefore loss of air passage becomes less.

Additionally, the dust guiding space can be provided as a tubular passage which an one end communicates with the suction opening so that the dust sucked from the suction opening flows in and an other end communicates with the dust collection section. Moreover, it is possible to provide an air guiding opening provided at a peripheral wall of the tubular passage and communicate with the intake opening of the motor fan.

BEST MODE FOR CARRYING OUT THE INVENTION

[Principle of the Invention]

First, a principle of the present invention will be described briefly with reference toFIG. 9.

InFIG. 9,100is a suction opening (intake vent) for sucking dust in a vacuum cleaner main body. A dust separation section101is provided between the suction opening100and a motor fan107.107A is an intake opening of the motor fan.

The dust separation section101has a tube section102which is forming a tubular passage102S that extends linearly and its cross-sectional area is constant, and a strike section103which is continuously built to an other side opening102A of the tube section102. The strike section103is communicated with the tube section102and is composed of a pipe section that protrudes to a lower direction.

103A is a wall of the strike section103, and the wall103A is adapted to be faced to the other side opening102A. And substantially, the wall103A is a dust strike section.

A dust collection room104is formed at a lower part of the strike section103. The dust collection room104and the tube section102are communicated through the strike section103which is more specifically, the pipe section. Additionally, the suction opening100, the tube section102and the motor fan107are arranged in alignment. Also, one end opening102B of the tube section102is communicated with the suction opening100.

A plurality of openings102H are formed at a peripheral wall of the tube section102. In addition, the dust separation section101is covered with a case105. The motor fan107is loaded to the case105, and the inside of the case105is adapted to be negatively pressured by the motor fan107.

Once the inside of the case105becomes the negative pressure by an activation of the motor fan107, the negative pressure acts upon the passage (tubular air passage)102S which is in the tube section102through the openings102H of the tube section102, and the dust is sucked together with air from the suction opening100. The air and the dust that are sucked from the suction opening100go straight through the passage102S within the tube section102, and the air is, on the way, sucked inside of the case105through the openings102H. The sucked air is sucked from the intake opening107A by the motor fan107. Normally, a filter for capturing microscopic dust is arranged in front of the intake opening107A.

On the other hand, the dust which has more weight than predetermined weight goes straight inside of the passage102S of the tube section102by inertia without change, and after hitting the wall103A of the strike section103, falls to the dust collection room104through a pipe section which composes the strike section103, and it becomes accumulated (deposited) at the dust collection room104.

As mentioned above, because the dust and the air are separated in the passage102S without generation of a spiral flow, a loss of air passage in the passage102S becomes less. Furthermore, as the suction opening100, the tube section102and the motor fan107are arranged in alignment, the air that is sucked to the opening107A flows virtually linearly and sucked by the motor fan107without changing its direction of the airflow significantly as shown by an arrow P. Consequently, since an overall loss of air passage becomes even less (i.e., overall loss in an amount of air passing through is less), performance of the motor fan107is improved.

In this principle, although the plurality of openings102H are provided at the pipe section102, it may be also recommendable to provide a single opening102H. In addition, the strike section103is not necessarily required to separate the dust from the air by an inertia force.

As described above, in this electric vacuum cleaner of the present invention of such principle, the dust separation section101is provided at a suction air passage leading from the suction opening100of the vacuum cleaner main body to the intake opening107A of the motor fan107to separate the dust that sucked from the suction opening100with the air and the dust collection section (dust collection room104) provided at the suction air passage for collecting the dust separated from the air at the dust separation section101. In addition, the dust separation section101has the tubular passage (passage102S) which communicates at one end with the suction opening100to flow the dust sucked from the suction opening100in the tubular passage and at the other end with the dust collection section (dust collection room104) and the air guiding opening (102H) which is provided at the peripheral wall of the tubular passage (102S) and which is communicated with the intake opening107A of the motor fan107.

Generally in the conventional electric vacuum cleaner of the cyclone type, since the air is, after swirled, reversed, drifted and sucked, therefore the loss of air passage of the air is large. Also in the conventional electric vacuum cleaner with the paper package as the paper filter, when a predetermined amount of dust is accumulated in the paper package, the amount of air decreases easily. On the contrary, in the electric vacuum cleaner of the present embodiment, because the dust sucked with the air goes straight by the inertia and is collected, and the air is sucked by the motor fan (107) through an air guiding opening (opening102H), the air and the dust are separated without generating spiral flow, therefore the loss of air passage becomes less.

Additionally, in this electric vacuum cleaner of the present invention of such principle, the dust separation section101is provided at the suction air passage which is leading from the suction opening100of the vacuum cleaner main body to the intake opening107A of the motor fan107to separate the dust sucked from the suction opening100with the air and the dust collection section (dust collection room104) provided at the suction air passage for collecting the dust separated from the air at the dust separation section101. Moreover, the dust separation section101has a dust guiding duct (passage102S) for inflowing the dust sucked from the suction opening100from one end of the duct and for guiding the dust that inflows from an other end to the dust collection section (dust collection room104) by the inertia force. Still moreover, an air passage for guiding air (air passage from the plurality of openings102H to the intake opening107A of the motor fan107) is provided to be communicated with a midstream of the dust guiding duct (passage102S) and is communicated with the intake opening107A of the motor fan107without passing through the dust collection section (dust collection room104).

As well as in this electric vacuum cleaner, as the dust sucked with the air goes straight by inertia and is collected, and the air is sucked by the motor fan (107) through the air guiding opening (opening102H), the air and the dust are separated without generating spiral flow, therefore the loss of air passage becomes less. By the way, in the principle of the present invention, although the dust guiding duct is formed in the linear shaped pipe section102, it is not necessarily limited to this. For example, the tube section102which the dust guiding duct is formed may also be shaped such that the diameter of the tube section102gradually decreases while going to a direction of a downstream of airflow, or on the contrary, in such a shape that expands its diameter as going to a direction of the downstream of airflow, or its cross section is square or polygon in shape. Also, it may also be recommendable to provide the tube section102with an inertia applying pipe section for applying a direct advancing inertia force to the dust and a dust guiding pipe section for guiding the dust which is going straight to a dust collection section (dust collection room104). In this instance, it may also be recommendable that the inertia applying pipe section and the dust collection section are separated as long as the inertia applying pipe section and the dust guiding pipe section are provided concentrically and a diameter of the dust guiding pipe section is formed larger enough than a diameter of the inertia applying pipe section.

More additionally, in this electric vacuum cleaner of the present invention of such principle, the dust separation section101is provided at the suction air passage leading from the suction opening100of the vacuum cleaner main body to the intake opening107A of the motor fan107to separate the dust sucked from the suction opening100with the air and the dust collection section (dust collection room104) provided at the suction air passage for collecting the dust separated from the air at the dust separation section101. Furthermore, the dust separation section101has the tubular passage (passage102S) as a dust guiding air passage (dust inflow air passage) which at one end is communicated with the suction opening100and adapted to flow in the dust sucked from the suction opening100, and an air guiding air passage provided with the air guiding opening (102H) which is provided on the peripheral wall of the passage (102S) at one end, and at the other end is communicated with the intake opening107A of the motor fan107without passing through the dust collection section (dust collection room104).

As well as in this electric vacuum cleaner, as the dust sucked with the air goes straight by the inertia and is collected, and the air is sucked by the motor fan (107) through the air guiding opening (opening102H), the air and the dust are separated without generating the spiral flow, therefore the loss of air passage becomes less.

[Mode for Carrying Out the Invention 1]

Next, embodiments of an electric vacuum cleaner applied with above mentioned principle of the invention will be described with reference to the accompanying drawings.

InFIG. 1,20is a vacuum cleaner main body, and one end of a hose21is connected attachably and detachably to the vacuum cleaner main body20and a hand operating pipe22is provided on the other end. An extension pipe23is connected attachably and detachably to the hand operating pipe22and a suction opening body24is connected to the end of the extension pipe23attachably and detachably. Also, a control section22A is provided on the hand operating pipe22, and there is provided on the control section22A a control switch which is not shown.

As shown inFIGS. 2 to 5, the vacuum cleaner main body20is provided with a main body case30and a dust collection case (dust cup, dust collection container)50which is attachably and detachably mounted on the main body case30and a lid body40capable of opening and closing in upward and downward directions, that a back end is connected to the main body case30by a hinge connection.

The main body case30has a motor-driven section34which is a rear case section loaded with a motor fan33. At a lower part of front side of the motor-driven section34, there is provided a mounting section35which is in a plate-shape that protrudes to a forward direction. Onto the mounting section35, the dust collection case50is attachably and detachably mounted. Furthermore, the dust collection case50is adapted to be fixed by holding of the lid body40and the mounting section35when the lid body40is closed.

Also, a front side of the motor-driven section34, that is, a front side of the rear case section has opening34A which is provided with a frame34bin a radial pattern for retaining a filter. The opening34A faces an intake opening33A of the motor fan33and are communicated.

At both side faces of the main body case30, an expanded section36is formed throughout an upper part of a front side and to a lower part of a back side. A rear wheel37is retained at a lower part of the expanded section36which is capable of revolving freely. Additionally, at a front side of both side faces of the expanded section36and the main body case30, a plurality of exhaust holes38are formed. These exhaust holes38are communicated with an exhaust opening33B of the motor fan33through an exhaust air passage which is not shown. By this, the air that is exhausted from the exhaust opening33B of the motor fan33is exhausted outside from the exhaust hole38through the exhaust air passage. Also, in the motor-driven section34of the main body case30, a battery which is not shown is contained at a lower part of the motor fan33.

The lid body40has a top panel41which is formed virtually elliptical in shape if seen in flatways, and a peripheral wall42is integrally formed at a perimeter of the top panel41. At a front part of this peripheral wall42, a connection pipe44which has a connection opening (suction opening)43for attachably and detachably connecting the dust collection hose21is provided. The connection pipe44extends in a longitudinal direction, and a back end45of it is opened.

With respect toFIGS. 6 to 8, the dust collection case50has a container case body53(shown inFIG. 7) which has an opening51on a rear face (right side inFIG. 6) and a suction opening (air inflow opening)52at a front face, and a handle section54which is integrally formed at below the suction opening52of the container case body53.

The container case body53has a dust collection room section (dust collection section)55formed at a lower part, a negative pressure room section56as an air guiding air passage formed above the dust collection room section55, a dust separation section60provided within the negative pressure room section56and a guide pipe70for guiding the dust separated at the dust separation section60to the dust collection room section55. In addition, the container case body53has a front wall53aand the suction opening52is formed at a side of an upper part of the front wall53a.

At a bottom of the dust collection room section55, a bottom plate57is attached capable of opening and closing about an axis J, and it is made capable of throwing away the dust accumulated in the dust collection room section55by opening the bottom plate57. A ventilation opening59as an exhaust opening (ventilation aperture) is formed at a top panel58of the dust collection room section55which divides the dust collection room section55and the negative pressure room section56. The ventilation opening59is closed by a net filter (exhaust filter) F1that is attached to the ventilation opening59.

A connection hole58A is formed behind the ventilation opening59of the top panel58. At lower part of the connection hole58A, there is provided a guide wall G to generate spiral flow at inside of the dust collection room section55.

The dust separation section60has a tubular filter62which forms a tubular passage (flow passage, or more specifically, the air passage)61, and a strike section63which is provided at an other end opening62B of the tubular filter62. A diameter of one end opening62A of the tubular filter62is formed larger than a diameter of the suction opening52. The one end opening62A of the tubular filter62and the suction opening52of the container case body53are connected so as the suction opening52to be located at an inner side. A diameter of the other end opening62B of the tubular filter62is set virtually similarly as the diameter of its suction opening52, and a diameter of the tubular filter62decreases gradually as going from one end to the other end linearly. That is to say, the tubular filter62of the dust separation section60is adapted to have a reducing diameter which is in a circular cone shape (taper shape) as gradually going to the downstream direction of the air passage. By the way, it may be recommendable to set the diameter of the other end opening62B of the tubular filter62smaller than the diameter of the suction opening52.

The passage61of the tubular filter62extends linearly to a longitudinal direction. The connection pipe44of the lid body40, the suction opening52of the container case body53, the tubular filter62, the opening51of the container case body53and the intake opening33A of the motor fan33are arranged in alignment.

As shown inFIG. 6, the tubular filter62has a tubular frame (equivalent to the tube section102indicated in the principle of the invention) W which is provided with a plurality of openings64as an air guiding opening, and a net filter (mesh shape filter) F2which is in a mesh shape attached to an inner peripheral side of the tubular frame W. The tubular frame W also has a frame section W1in a circular shape (round shape) forming the one end opening62A, a frame section W2which is in a round shape and a tubular shape (circular shape) forming the other end opening62B, and a plurality of frame sections W3(rib shaped frame section) which are in a rib shape that connect the frame sections W1and W2. By the way, the spaces surrounded by each frame sections W1-W3are the openings (air guiding opening)64. The openings64as an air guiding opening are equally provided throughout entire circumference of the tubular filter62. In addition, the passage61is formed and surrounded by the frame sections W1-W3and the net filter F2. InFIG. 7, indication of the net filter F2shown inFIG. 6has been omitted as a matter of convenience to describe the openings64.

Furthermore, the net filter F2is formed in a tubular shape along the inner periphery of the tubular frame W as a filter tube section, and is attached to the tubular frame W by adhesion or fusion bonding for example in such a manner as to cover the plurality of openings64. Moreover, a metallic coating layer formed on a surface of a mesh shape resin fiber by sputtering is used for the net filter F2, therefore the net filter F2is made to provide extremely easy slippage so as to avoid an attachment of the dust.

The passage61of the tubular filter62is communicated with the intake opening33A of the motor fan33through the openings64of the tubular filter62, the negative pressure room section56of the container case body53and the opening34A of the motor-driven section34of the main body case30. Also, the extending directions of the passage61of the tubular filter62and the connection pipe44of the lid body40are in alignment, and the intake opening33A of the motor fan33faces toward the extending of direction the passage61of the tubular filter62.

The strike section63has a slant wall section63A extending from an upper side of the other end opening62B of the tubular filter62to a lower side on a slant, and a strike wall section63B which faces to the other end opening62B of the tubular filter62and is also incurved from one end of the slant wall section63A and extending to a lower part, and a side wall section63C which is formed at both sides of the slant wall section63A and the strike wall section63B. Additionally, the strike section63has an opening63D jointed to the other end opening62B of the tubular filter62and also has an opening63E which faces to a lower part.

The guide pipe70extends in a vertical direction, and is communicated with inside of the dust collection room section55through the opening63E of the strike section63and the connection hole58A of the top panel58.

Further, there is fitted a filter80at the opening51of the container case body53to capture the microscopic dust failed to be captured by the net filters F1and F2. Furthermore, the filter80is pressed and attached by the motor-driven section, that is, by a frame34bwhich is provided at the front surface of the rear case section.

Next, an operation of the electric vacuum cleaner constituted as above will be described.

First, as shown inFIG. 4, the dust collection case50is mounted on the mounting section35of the main body case30and then the lid body40is closed, and the hose21is connected to the connection opening43of the lid body40. When controlling the switch (not shown) of the control section22A, the motor fan23actuates. By the actuation of the motor fan23, the negative pressure room section56of the container case body53becomes the negative pressure through the opening34A of the main body case30. This negative pressure acts upon the openings64of the tubular filter62, the passage61of the tubular filter62, the suction opening52of the container case body53, the connection pipe44of the lid body40, the hose21, the extension pipe23and the suction opening body24, thereby the dust on a cleaning surface is sucked together with the air from the suction opening body24.

The sucked dust and air are adapted to be sucked to the connection opening43of lid body40through the extension pipe23and the hose21. The dust and the air that are sucked to the connection opening43are adapted to be sucked to the passage61of the tubular filter62of the dust separation section60through the suction opening52of the dust collection case50.

Some of the air sucked to the passage61passes through the net filter F2of the openings64of the tubular filter62, and sucked to the negative pressure room section56of the container case body53, and furthermore, passes through the filter80loaded at the opening51of the container case body53and sucked by the intake opening33A of the motor fan33. At this time, the microscopic dust that passed through the net filter F2is captured by the filter80.

On the other hand, because the passage61extends linearly to the longitudinal direction, the dust which is sucked to the passage61of the tubular filter62and which has more weight than predetermined weight goes straight through the passage61and hits the strike wall section63B of the strike section63, and is adapted to be introduced inside of the dust collection room section55by the guide pipe70. That is to say, the dust and the air are separated by the dust separation section60.

Also, some of the air is adapted to be introduced inside of the dust collection room section55through the strike section63and the guide pipe70, and the introduced air turns into spiral flow by the guide wall G of the dust collection room section55, and the dust introduced inside of the dust collection room section55is accumulated as it is compressed by the spiral flow.

The air introduced into the dust collection room section55is, when turned into spiral flow, passes through the ventilation opening59of the top panel58of the dust collection room section55and the net filter F1, and is sucked to the negative pressure room section56of the container case body53. At this time, the microscopic dust which has passed through the net filter F1is sucked together with the air to the negative pressure room section56. In addition, the air sucked to the negative pressure room section56is further sucked by the intake opening33A of the motor fan33through the filter80which is loaded at the opening51of the container case body53. At this time, the microscopic dust which passed through the net filter F1is captured by the filter80.

In this way, the air that is exhausted through the openings64and the air that is exhausted through the ventilation opening59are converged together at the negative pressure room section56. Further, the converged air is adapted to be sucked by the intake opening33A of the motor fan33through the filter80which is loaded at the opening51of the container case body53. As stated above, the microscopic dust which passed through the net filters F1and F2is captured by the filter80at this time.

By the way, light weighted microscopic dust in the dust which is sucked to the passage61of the tubular filter62attaches to the net filter F2since it flows with the air that passes the net filter F2of the openings64without going straight through the passage61of the tubular filter62. If clogging of the net filter F2caused by the attachment of the microscopic dust becomes larger, the amount of wind that goes through the net filter F2reduces, but the negative pressure of the negative pressure room section56of the container case body53increases corresponding to the amount it reduced as well as the negative pressure within the dust collection room section55through the ventilation opening59of the top panel58. Consequently, a wind velocity of the air that goes straight through the passage61of the tubular filter62becomes greater, therefore the amount of wind which goes straight increases.

When the wind velocity that goes straight through the passage61of the tubular filter62becomes greater, the air that goes straight forward peels off the dust attached to the net filter F2. On this occasion, because the diameter of the tubular filter62gradually decreases as going linearly to the side of the opening62B, the wind that goes straight through the passage61becomes easier to hit the entire side of the net filter F2, therefore the dust attached to the net filter F2is easily peeled off.

The peeled dust is adapted to be introduced and accumulated in the dust collection room section55through the strike section63and the guide pipe70.

Also, even if the amount of wind that passes through the net filter F2is reduced by clogging, the amount of wind the motor fan33sucks can be maintained constant because the amount of wind goes straight through the passage61of the tubular filter62increases. Consequently, it is always possible to suck the dust by a predetermined sucking power with irrespective of clogging of the net filter F2.

Additionally, by a fact that the dust and the air are not separated by generation of spiral flow within the passage61of the tubular filter62, the loss of air passage within the passage61becomes less. Furthermore, when the air sucked from the passage61of the tubular filter62to the negative pressure room section56of the container case body53through the net filter F2, the flowing direction of air does not change significantly as shown by the arrow Q (seeFIG. 3), because the suction opening52, the tubular filter62, the opening51of the container case body53and the intake opening33A of the motor fan33are arranged in alignment, therefore flows virtually linearly to the motor fan33to be sucked.

Consequently, the loss of air passage becomes even less (i.e., loss in an amount of air passing through becomes even less), so that the performance of the motor fan33can be achieved sufficiently. Further, because the connection pipe44of the lid body40and the tubular filter62are arranged in a straight line, a direction of the air introduced to the suction opening52of the container case body53becomes in alignment with the extending direction of the tubular filter62, therefore its loss of air passage becomes even more less.

Moreover, by providing the dust collection room section55below the dust separation section60and by providing the ventilation opening59at the top panel58of the dust collection room section55, the ventilation opening59which communicates the dust collection room section55and the negative pressure room section56penetrates the top panel58in a vertical direction. By this structure, the dust attached to the net filter F1which is fixed to the ventilation opening59falls to a lower part by its own weight and is accumulated inside of the dust collection room section55. Also, the clogging is hard to occur since the dust attached to the net filter F1can be removed easily, therefore the deterioration in sucking efficiency can be avoided.

According to the present invention as described above, it is possible to reduce the loss of air passage, and even amount of wind at the suction opening does not decrease even if the dust accumulates, therefore it is always possible to suck the dust by a predetermined sucking power.

[Mode for Carrying Out the Invention 2]

FIGS. 10-13show an electric vacuum cleaner corresponding to the second embodiment of the present invention. The same reference numbers indicated inFIGS. 1-8are given for the parts identical or resembles to the structure of the embodiment shown inFIGS. 1-8, and their descriptions are omitted.

The dust separation section60in the second embodiment of the present invention has, as mentioned above, the tubular filter62formed with the passage61which is in a tubular shape and a strike member (tubular body) provided with the strike section63which is set at the other end opening62B of the tubular filter62. As shown inFIGS. 10 and 11, a diameter D1of the one end opening62A of the tubular filter62is formed larger than a diameter d of the suction opening (air inflow opening)52of the container case body53, and a diameter D2of the other end opening62B of the tubular filter62is formed larger than a diameter of its suction opening52. That is to say, the diameter d of the suction opening (air inflow opening)52is formed smaller than the diameter D2of the other end opening62B of the tubular filter62.

When the air containing the dust flows and enters in the tubular filter62from the suction opening52, the air containing the dust flows to the direction of the one end opening62B from the one end opening62A of the tubular filter62, therefore the one end opening62A of the tubular filter62becomes as an upstream end and the other end opening62B becomes as a downstream end in consideration of the flow of air. Further, the one end opening62A (upstream end) of the tubular filter62is closely contacted or fixed to a rear side of the front wall53aof the container case body53at a periphery of the suction opening (air inflow opening)52. Thereby the suction opening52of the container case body53and the one end opening62A are each connected so as to set the suction opening52at the position which is inside of the one end opening62A. In addition, the diameter of the one end opening62A (upstream end) of the tubular filter62is formed larger than the diameter of the suction opening52.

Also, the diameter of the tubular filter62gradually decreases as going linearly to the other end (downstream end) from the one end (upstream end). In other words, the diameter of the tubular filter62of the dust separation section60is gradually adapted to diminish in a circular cone shape (taper shape) as going to the downstream direction of the air passage.

Moreover, the passage61of the tubular filter62extends linearly to a longitudinal direction, and the connection pipe44of the lid body40, the suction opening52of the container case body53, the tubular filter62, the opening51of the container case body53and the intake opening33A of the motor fan33are arranged in alignment.

As shown inFIG. 11, the tubular filter62has the tubular frame W which is provided with the plurality of openings64, and the net filter (mesh shaped filter) F2which is in a mesh shape attached to an inner peripheral side of the tubular frame W (seeFIG. 12). The tubular frame W also has the frame section W1which is in a circular shape (round shape) forming the one end opening62A, the frame section W2which is in a round shape and a tubular shape (circular shape) forming the other end opening62B, and the plurality of frame sections W3(rib shaped frame section) which are in rib shape that connect the frame sections W1and W2(seeFIGS. 11-13). By the way, the spaces surrounded by each frame sections W1-W3are the openings64. The openings64are equally provided throughout the entire circumference of the tubular filter62. In addition, the passage61is formed and surrounded by the frame sections W1-W3and the net filter F2.

Also, the net filter F2is formed in a tubular shape along the inner periphery of the tubular frame W as the filter tube section, and is attached to the tubular frame W by adhesion or fusion bonding for example in such a manner as to cover the plurality of openings64.

Additionally, in the tubular frame W, the diameter D1of the upstream end is formed larger than the diameter d of the suction opening (air inflow opening)52and the diameter D2of the downstream end is formed larger than the diameter d of the suction opening (air inflow opening)52. In other words, the diameter d of the suction opening (air inflow opening)52is formed smaller than the diameter D2of the downstream end (other end opening62B) of the tubular frame W. Also, the suction opening52, the one end opening62A and the other end opening62B are provided substantially concentric.

Furthermore, a metallic coating layer formed on the surface of the mesh shape resin fiber by the sputtering is used for the net filter F2, thereby the net filter F2is made to provide extremely easy slippage so as to avoid attachment of the dust.

Moreover, as shown inFIG. 13, if a coarseness of a mesh (opening) Ma of the net filter F2of the tubular filter62is S1, more specifically, if a dimension of an opening of mesh (net) is S1, and if the coarseness of a mesh (opening) Mb of the net filter F2attached to the ventilation opening59which is an exhaust opening is S2, more specifically, if a dimension of an opening of mesh (net) is S2, then the dimension of the mesh opening S1of the net filter F2is formed smaller than the dimension of the mesh opening S2of the net filter F1(exhaust filter).

Also, if an amount of wind of the air that passes through the tubular filter62and inflows (sucked) to the negative pressure room section56is Q1, and if an amount of wind of the air that inflows (sucked) to the negative pressure room section56through the ventilation opening59which is as the exhaust opening and the net filter F1is Q2, then the amount of wind of the air Q1that passes through the net filter F2of the tubular filter62is set less than the amount of wind of the air Q2that passes through the net filter F1of the dust collection room section (dust collection section)55. That is to say, the amount of wind Q2is set larger than the amount of wind Q1.

A relation between the wind amounts Q1and Q2is determined through various conditions such as a sucking performance of the motor fan33, the coarseness of mesh of the net filters F1and F2(size of the opening (opening) of mesh) and cross-sectional area or length of each air passages. But the relation between the wind amounts Q1and Q2can be changed by the coarseness (size of the opening of mesh) of mesh of the net filters F1and F2as long as the conditions other than the net filters F2and F2are determined and are constant.

In addition, the passage61of the tubular filter62is communicated with the intake opening33A of the motor fan33through the openings64of the tubular filter62, the negative pressure room section56of the container case body53and the opening34A of the motor-driven section34of the main body case30. Also, the extending directions of the passage61of the tubular filter62and the connection pipe44of the lid body40are in alignment, and the intake opening33A of the motor fan33faces toward the extending direction of the passage61of the tubular filter62.

The strike section63has the slant wall section63A extending from the upper side of the other end opening62B of the tubular filter62to the lower side on a slant, and the strike wall section63B which faces to the other end opening62B of the tubular filter62and which is also incurved from the one end of the slant wall section63A and extending to the lower part, and the side wall section63C formed at both sides of the slant wall section63A and the strike wall section63B. Additionally, the strike section63has an opening63D jointed to the other end opening62B of the tubular filter62and also has an opening63E which faces the lower part.

The strike section63is provided at upper part of the guide pipe70which is separately formed to the tubular filter62as shown inFIGS. 11 and 12. The guide pipe70extends in a vertical direction and is communicated with inside of the dust collection room section55through the opening63E of the strike section63and the connection hole58A of the top panel58.

By the way, it may be recommendable to form the tubular filter62, the strike section63and the guide pipe70integrally and form separately from the container case body53, and fix to the top panel58of the dust collection room section55of the container case body53by adhesion or supersonic fusion bonding. Also, it may be recommendable to form the strike section63and the guide pipe70integrally and form separately from the tubular filter62and the container case body53, and fix the tubular filter62to the strike section63and the front wall53aby adhesion or supersonic fusion bonding together with fix a lower end of the guide pipe70to the top panel58by adhesion or supersonic fusion bonding.

Next, an operation of the electric vacuum cleaner constituted as above will be described hereinafter.

As mentioned above, the dust on a cleaning surface is sucked with the air inside of the tube shaped passage61by operating the motor fan33. Some of the air sucked to the passage61(particularly a peripheral air of the airflow that flows into the passage61) passes through the net filter F2of the openings64of the tubular filter62and sucked to the negative pressure room section56of the container case body53, and further sucked by the intake opening33A of the motor fan33through the filter80loaded at the opening51of the container case body53. On this occasion, the microscopic dust which passed through the net filter F2is captured by the filter80.

Meanwhile, because the passage61extends linearly to the longitudinal direction, the dust which is sucked to the passage61of the tubular filter62and which has more weight than predetermined weight and the remaining air (air) go straight through the passage61and hit the strike wall section63B of the strike section63.

At this time, in the dust that inflows with an atmospheric air (air) from the suction opening52into the passage61, although the light dust is in some of the air which is at a side of the net filter F2, the other air goes virtually straight forward by the inertia force. Since the light dust is relatively light in weight, the inertia energy is less. The dust that goes straight forward is relatively heavy in weight and therefore the inertia energy is large.

Therefore, within the dust that inflows from the suction opening52, when the dust that goes virtually straight forward by the inertia force caused when flowing into the passage61from the suction opening52hits the downstream end part of the net filter (filter tube section) F2, the dust breaks into the mesh (mesh opening) of the downstream end part of the filter F2by the inertia energy, thereby the downstream end part of the net filter F2clogs and a permeability loses, as a result, a recovery in the permeability cannot be expected.

But in the present embodiment, since a vast majority of dust that flows into the passage61from the suction opening52and also the dust at the periphery part go straight forward by the inertia energy, and in addition, since the diameter d of the suction opening52is formed smaller than the diameter D2of the opening62B which is the downstream end of the tubular filter62, the dust that goes virtually straight forward by the inertia force caused when flowing into the passage61from the suction opening52hits the strike wall section63B of the strike section63without hitting the downstream end of the filter F2. Therefore, clogging at the downstream end of the net filter (filter tube section) F2caused by the dust flowing into the passage61from the suction opening52and going straight forward can be avoided. On this occasion, the remaining air that goes straight without passing through the net filter F2also hits the strike wall section63B of the strike section63.

In addition, the dust struck the strike wall section63B and the remaining air which goes straight without passing through the filter F2are biased to a lower direction and then adapted to be introduced inside of the dust collection room section55by the guide pipe70. As described, some of the air and the dust are separated by the dust separation section60, and the separated dust and the remaining air are adapted to be introduced inside of the dust collection room section55by the guide pipe70.

The air that is introduced inside of the dust collection room section55becomes spiral flow by the guide wall G of the dust collection room section55, and accumulates the dust on a bottom side of the dust collection room section55while compressing the dust which is introduced inside of the dust collection room section55. Later, the air passes through the ventilation opening59of the top panel58of the dust collection room section55and the net filter F1, and is sucked to the negative pressure room section56of the container case body53.

On this occasion, the microscopic dust which passed through the net filter F1is sucked together with the air to the negative pressure room section56. In addition, the air that is sucked to the negative pressure room section56is furthermore sucked by the intake opening33A of the motor fan33through the filter80which is loaded at the opening51of the container case body53. The microscopic dust that passed through the net filter F1is captured by the filter80at this time.

In this manner, the air exhausted through the openings64, and the air exhausted through the ventilation opening59are converged together at the negative pressure room section56. Further, the converged air is sucked by the intake opening33A of the motor fan33through the filter80which is loaded at the opening51of the container case body53. As stated above, the microscopic dust which passed through the net filters F1and F2is captured by the filter80.

In addition, the amount of wind of the air Q1that passes through the net filter F2as mentioned above is set less than the amount of wind of the air Q2that is sucked inside of the negative pressure room section56through the guide pipe70, the dust collection room section55and the opening (exhaust opening). Consequently, the vast majority of the dust flowing into the tubular filter12from the suction opening52flows the passage61in the tubular filter62linearly toward the strike wall section63B of the strike section63. Therefore, a separation rate of the dust at inside of the tubular filter62increases, that is, within the dust flowing into the tubular filter62, a proportion of flowing toward the strike wall section63B without flowing to the side of the net filter F2of the tubular filter62increases. This separation rate increases more as the amount of wind Q2becomes larger to the amount of wind Q1.

Furthermore, the light weighted microscopic dust attaches to the net filter F2since it flows with the air that passes the net filter F2of the openings64without going straight through the passage61of the tubular filter62. If the clogging of the net filter F2caused by the attachment of the microscopic dust becomes larger, the amount of wind that goes through the net filter F2reduces, but the negative pressure of the negative pressure room section56of the container case body53increases corresponding to the amount it reduced as well as the negative pressure within the dust collection room section55through the ventilation opening59of the top panel58. Consequently, the wind velocity of the air that goes straight through the passage61of the tubular filter62becomes greater, therefore the amount of wind which goes straight increases. When the wind velocity that goes straight through the passage61of the tubular filter62become greater, the air that goes straight peels off the dust attached to the net filter62.

By the way, the mesh opening (coarseness) S1of mesh of the net filter F2of the tubular filter62is set smaller than the mesh opening (coarseness) S2of mesh the net filter F1. Consequently, the power increases, that is to say, the amount of wind sucking the dust to the dust collection room section55increases, therefore, the net filter F2becomes hard to be clogged.

In addition, even if the amount of wind that passes through the net filter F2is reduced by clogging, the amount of wind that the motor fan33sucks can be maintained constantly, because the amount of wind that goes straight through the passage61of the tubular filter62increases. Consequently, it is always possible to suck the dust by a predetermined sucking power irrespective of the clogging of the net filter F2.

Also, by the fact that the dust and the air are not separated by generation of spiral flow within the passage61of the tubular filter62, the loss of air passage within the passage61becomes less. Furthermore, when the air is sucked from the passage61of the tubular filter62to the negative pressure room section56of the container case body53through the net filter F2, the flowing direction of air does not change significantly as shown by the arrow Q (seeFIG. 3), since the suction opening52, the tubular filter62, the opening51of the container case body53and the intake opening33A of the motor fan33are arranged in alignment, therefore it flows virtually linearly to the motor fan33to be sucked.

Consequently, the loss of air passage becomes even less, as a result, the performance of the motor fan33can be achieved sufficiently. Further, because the connection pipe44of the lid body40and the tubular filter62are arranged in a straight line, the direction of the air introduced to the suction opening52of the container case body53becomes in alignment with the tubular filter62, therefore its loss of air passage (i.e., loss of an amount of air passing through) becomes even lesser.

As described above, the electric vacuum cleaner in the second embodiment of the present invention is comprised of the dust separation section60which is provided at the suction air passage leading from the suction opening52of the vacuum cleaner main body20to the intake vent (intake opening33A) for separating the dust from the air sucked from the suction opening, and the dust collection section (dust collection room section55) provided at the suction air passage for capture and collect the dust that are separated from the air at the dust separation section60. Furthermore, the dust separation section60has the tubular filter62, and the cross-sectional area of the air inflow opening (the suction opening52of the present embodiment acts as both the suction opening for the vacuum cleaner main body and the air inflow opening to the tubular filter62) which compared to the tubular filter62is smaller than the cross-sectional area of the air exhaust end (the other end opening62B) which is to the tubular filter62. This relation is set by setting the diameter d of the suction opening52so as to become smaller than the diameter D2of the other end opening62B of the tubular filter62, in the present embodiment.

According to the above mentioned structure, the dust that goes substantially straight by the inertia force caused when flowing from the suction opening52into the passage61does not hit the downstream end part of the tubular filter62. By this structure, the clogging of the downstream end part of the net filter (filter tube section) F2by the dust that flows and goes straight from the suction opening52into the passage61can be avoided.

Also, according to the electric vacuum cleaner described in the second embodiment of the present invention, the dust collection section (dust collection room section55) has an exhaust opening (ventilation opening59) which is communicated with the intake vent (intake opening33A) of the motor fan33. Further, the amount of wind Q1that passes through the net filter F2of the tubular filter62(without passing through the dust collection room section55) is set less than the amount of wind Q2that flows to the intake vent (intake opening33A) of the motor fan33through the dust collection section (dust collection room section55) and the exhaust opening (ventilation opening59).

According to this structure, the separation rate of the dust inside of the tubular filter62, that is, the ratio of within the dust that flows into the tubular filter62and that goes straight without flowing to the side of the mesh of the tubular filter62increases.

Furthermore, according to the electric vacuum cleaner described in the second embodiment of the present invention, a mesh shape filter (net filter F2) is used for the tubular filter62, and an exhaust filter (net filter F1) in a mesh shape is attached to the exhaust opening (ventilation opening59) and, the dimension of the opening S1of the mesh of the tubular filter62is set smaller than the dimension of the opening S2of mesh of the exhaust filter (net filter F1).

According to this structure, since the power rises, more specifically, since the amount of wind sucking the dust to the dust collection room (dust collection room section55) becomes larger, the net filter F2becomes hard to clog.

According to the invention as described above, the loss of air passage (i.e., loss in an amount of air passing through) can be made small, and the amount of wind does not decrease even if the dust accumulates, and the dust attached to a dust separation means which separates the dust from the air can be easily removed.

[Mode for Carrying Out the Invention 3]

FIGS. 14 and 15show an electric vacuum cleaner corresponding to the third embodiment of the present invention. The same reference numbers indicated inFIGS. 1-8are given for the parts identical or resembles to the composition of the embodiment shown inFIGS. 1-8, and their descriptions are omitted.

The dust separation section60in the third embodiment of the present invention has, as mentioned above, the tubular filter62forming the passage61which is in a tubular shape and the strike member (tubular body) provided with the strike section63which is provided at the other end opening62B of the tubular filter62. As shown inFIGS. 14 and 15, a diameter d1of the one end opening62A of the tubular filter62is formed larger than a diameter d2of the suction opening (air inflow opening)52of the container case body53, and a diameter d3of the other end opening62B of the tubular filter62is formed smaller than the diameter d2of its suction opening52.

Here, when the air containing the dust flows and enters in the tubular filter62from the suction opening52, the air containing the dust flows to the direction of the one end opening62B from the one end opening62A of the tubular filter62, therefore the one end opening62A of the tubular filter62becomes as the upstream end, and the other end opening62B becomes as the downstream end in consideration of the flow of air. In addition, the one end opening62A (upstream end) of the tubular filter62is closely contacted or fixed to the rear side of the front wall53aof the container case body53in a periphery of the suction opening (air inflow opening)52. Thereby the suction opening52of the container case body53and the one end opening62A are each connected so as to set the suction opening52at a position which is inside of the one end opening62A.

Also, the diameter of the tubular filter62gradually decreases as going linearly to the other end (downstream end) from the one end (upstream end). In other words, the diameter of the tubular filter62of the dust separation section60is adapted to be gradually diminished in the circular cone shape (taper tube shape) as going to the downstream end.

Furthermore, the passage61of the tubular filter62extends linearly in the longitudinal direction, and the connection pipe44of the lid body40, the suction opening52of the container case body53, the tubular filter62, the opening51of the container case body53and the intake opening33A of the motor fan33are arranged in alignment.

Also, the tubular filter62has the tubular frame W which is provided with the plurality of openings64and the net filter (mesh shaped filter, filter tube section) F2which is in the tubular shape and in the mesh shape that is attached to the inner peripheral side of the tubular frame W. The tubular frame W has the frame section W1in the circular shape (round shape) which is forming the one end opening62A, the frame section W2which is in the round shape and in the tubular shape (circular shape) that is forming the other end opening62B, and the plurality of frame sections W3(rib shaped frame section) in a rib shape which connect the frame sections W1and W2. By the way, the spaces surrounded by each frame sections W1-W3are the openings64. The openings64are equally provided throughout the entire circumference of the tubular filter62. In addition, the passage61is formed and surrounded by the frame sections W1-W3and the net filter F2.

Moreover, the net filter F2is adapted to be as a filter tube section formed in a tubular shape along the inner periphery of the tubular frame W, and is attached to the tubular frame W by adhesion or fusion bonding for example in such a manner as to cover the plurality of openings64. Also, the frame section W2of the tubular frame W is formed in a wide range and is adapted to be a non-mesh tube section. In the frame section W2as the non-mesh tube section, a diameter d4of the up stream end is formed larger than the diameter d2of the suction opening (air inflow opening)52, and the diameter of the downstream end d3is formed smaller than the diameter d2of the suction opening (air inflow opening)52. By this, a periphery of the suction opening52corresponds with an intermediate part of the frame section W2in an air passage direction, and the dust at a periphery within the dust in the air that flows-in from the suction opening52to the passage61is adapted to be moved toward the frame section W2by the inertia force caused when flowing in. By the way, the suction opening52, the one end opening62A and the other end opening62B are formed substantially concentric.

In the net filter F2, the coarseness of mesh of the mesh shape, that is, the opening of the mesh (net) is formed gradually or step-by-step smaller as going from the up stream side to the down stream side of the passage61. For example, in the net filter F2, the coarseness of the mesh of the mesh shape, that is, the opening of the mesh or net is formed gradually or step by step smaller between 110 μm-30 μm as going from the up stream side to the down stream side of the passage61.

Furthermore, a metallic coating layer formed on the surface of the mesh shape resin fiber by the sputtering is used for the net filter F2, therefore the net filter F2is made to provide extremely easy slippage so as to avoid the attachment of the dust.

Next, the operation of the electric vacuum cleaner constituted as above will be described hereinafter.

As mentioned above, the dust on a cleaning surface is sucked with the air in the passage61of the tubular filter62of the dust separation section60by activating the motor fan33. The air that is sucked to the passage61is sucked to the negative pressure room section56of the container case body53through the net filter F2of the openings64of the tubular filter62, and is further sucked by the intake opening33A of the motor fan33through the filter80loaded at the opening51of the container case body53. On this occasion, the microscopic dust which passed through the net filter F2is captured by the filter80.

Meanwhile, because the passage61extends linearly to the longitudinal direction, the dust that is sucked to the passage61of the tubular filter62and has more weight than predetermined weight goes straight through the passage61and hits to the strike wall section63B of the strike section63.

On this occasion, within the dust that is flown from the suction opening52and within them at a periphery area, and the dust that goes substantially straight by the inertia force caused when flowing in from the suction opening52into the passage61has a large inertia energy. Consequently, when the dust that flows in from the suction opening52and within them at the periphery area and the one that goes substantially straight by the inertia force caused when flowing into the passage61from the suction opening52hits the downstream end part of the net filter (filter tube section) F2, the mesh (mesh opening) of the downstream end part of the filter F2becomes clogged by the inertia energy and thereby permeability loses, and the recovery of the permeability cannot be expected.

But in the present embodiment, because within the dust that is flown from the suction opening52and within them at the periphery area, and the one that goes substantially straight by the inertia force caused when flowing into the passage61from the suction opening52hits the strike wall section63B of the strike section63after hitting the frame section W2as the non-mesh section without hitting the downstream end part of the filter F2, the clogging at the downstream end part of the net filter (filter tube section) F2can be reduced. The dust that struck the strike wall section63B is introduced inside of the dust collection room section55by the guide pipe70. In this manner, the air and the dust are separated by means of the dust separation section60.

Also, some of the air is adapted to be introduced inside of the dust collection room section55through the strike section63and the guide pipe70, and the introduced air turns to spiral flow by the guide wall G of the dust collection room section55, and the dust that is introduced inside of the dust collection room section55is adapted to be accumulated as it is compressed by spiral flow.

The air that is introduced inside of the dust collection room section55becomes spiral flow by the guide wall G of dust collection room section55, and adapted to accumulate the dust introduced inside of the dust collection room section55to the bottom side of dust collection room section55as the air compresses the dust. Then, the air percolates the ventilation opening59of the top panel58of the dust collection room section55and the net filter F1, and sucked to the negative pressure room section56of the container case body53.

On this occasion, the microscopic dust which passed through the net filter F1is sucked together with the air to the negative pressure room section56. In addition, the air that is sucked to the negative pressure room section56is furthermore sucked by the intake opening33A of the motor fan33through the filter80which is loaded at the opening51of the container case body53. The microscopic dust that passed through the net filter F1is captured by the filter80at this time.

In this manner, the air exhausted through the openings64, and the air exhausted through the ventilation opening59are converged together at the negative pressure room section56. Further, the converged air is sucked by the intake opening33A of the motor fan33through the filter80which is loaded at the opening51of the container case body53. As stated above, the microscopic dust which passed through the net filters F1and F2is captured by the filter80.

Because the light weight microscopic dust flows with the air that passes the net filter F2of the openings64without going straight through the passage61of the tubular filter62, it attaches to the net filter F2. In addition, if the clogging of the net filter F2caused by the attachment of the microscopic dust becomes larger, the amount of wind that goes through the net filter F2reduces, but the negative pressure of the negative pressure room section56of the container case body53increases corresponding to the amount it reduced as well as the negative pressure within the dust collection room section55through the ventilation opening59of the top panel58. Consequently, the wind velocity of the air going straight through the passage61of the tubular filter62becomes greater, and the amount of wind which goes straight increases. When the wind velocity that goes straight through the passage61of the tubular filter62become greater, the air that goes straight peels off the dust attached to the net filter F2.

As stated, the wind (air) contains the microscopic and relatively light dust, and this light dust is adapted to be captured by the net filter F2. It is in such a state that it can easily be peeled off since the inertia energy of the light dust is less and therefore it will not hit the mesh (net) of the net filter F2strongly. Also, within the dust contained in the wind (air), although the dust that is flown from the suction opening52to the passage61and within them at the periphery area and the one that goes substantially straight by the inertia force caused when flowing in from the suction opening52into the passage61has the large inertia energy, this dust hits the wide ranged frame section (non-mesh section) W2without hitting the net filter F2, therefore the cause for the clogging of the mesh (net) of the net filter F2can be evaded.

Therefore, when the dust captured by the net filter F2reaches a predetermined amount, it is peeled off easily from the net filter F2by the sucked air that is sucked to the passage61, and the dust peeled from the net filter F2is adapted to be introduced and accumulated in the dust collection room section55through the strike section63and the guide pipe70.

Furthermore, because the diameter of the tubular shaped net filter F2is gradually decreased as going linearly from the upstream end to the downstream end, the wind that goes to the side of the mesh (net) of the net filter F2without going straight through the passage61in the net filter F2becomes easier to attach entire surfaces of the net filter F2equally. Moreover, this wind (air) contains the relatively light dust, and this light dust hits the entire surfaces of the net filter F2equally and is adapted to be captured by the net filter F2. It is in such a circumstance that the light dust can easily be peeled off since the light dust has the less inertia energy and therefore it will not break into the mesh (net) of the net filter F2strongly.

In addition, even if the amount of wind that passes through the net filter F2is reduced by the clogging, the amount of wind that the motor fan33sucks can be maintained constantly because the amount of wind goes straight through the passage61of the tubular filter62increases. Consequently, it is always possible to suck the dust by a predetermined sucking power regardless of the clogging in the net filter F2.

Also, by the fact that the dust and the air are not separated by generation of spiral flow within the passage61of the tubular filter62, the loss of air passage (i.e., loss in an amount of air passing through) within the passage61becomes less. Furthermore, when the air is sucked from the passage61of the tubular filter62to the negative pressure room section56of the container case body53through the net filter F2, the direction of the airflow does not change significantly as shown by the arrow Q (seeFIG. 3), because the suction opening52, the tubular filter62, the opening51of the container case body53and the intake opening33A of the motor fan33are arranged in alignment, therefore flows virtually linearly to the motor fan33to be sucked.

Consequently, the loss of air passage (i.e., loss in an amount of air passing through) becomes even less, and the performance of the motor fan33is improved. Further, because the connection pipe44of the lid body40and the tubular filter62are arranged in a straight line, the direction of the air introduced to the suction opening52of the container case body53becomes in alignment with the extending direction the tubular filter62, therefore its loss of air passage (i.e., loss in an amount of air passing through) becomes evenlesser.

As described above, the electric vacuum cleaner in the third embodiment of the present invention comprises the dust separation section60provided at the suction air passage leading from the suction opening52of the vacuum cleaner main body20to an intake vent (opening34A) of the motor fan33for separating the dust from the air sucked to the suction opening52, and the dust collection section (dust collection room section55) provided at the suction air passage for capturing and collecting the dust separated from the air at the dust separation section60. Furthermore, the dust separation section60has the filter tube section (net filter F2) in a mesh shape which is located at the upstream side and the non-mesh tube section (frame section W2) which is communicated with the lower stream end of the filter tube section (net filter F2).

According to this structure, the light dust that flows into the filter tube section (net filter F2) is captured by the filter tube section (net filter F2). It is in such a state that the light dust can easily be peeled off since the inertia energy of the light dust is less and therefore it will not break strongly into the mesh (net) of the filter tube section. Also, within the dust contained in the wind (air), although the dust that is flown from the suction opening52to the passage61and within them at the periphery area and the one that goes substantially straight by the inertia force caused when flowing from the suction opening52into the passage61which is inside of the filter tube section has the large inertia energy, this dust hits the wide ranged non-mesh section (frame section W2) without hitting the net filter F2, therefore the cause for clogging of the mesh (net) of the filter tube section (net filter F2) can be evaded.

In the embodiment described above, although the tubular filter62and the filter tube section (net filter F2) are formed in a circular cone shape, that have their diameters which diminish gradually as going to the direction of the down stream side, it is possible to form the tubular filter62and the filter tube section (net filter F2) in the tubular shape which has substantially the same diameter from the upstream end to the downstream end. As well as in this case, when the dust that flows into the filter tube section, and within them at the periphery part that goes substantially straight hits the downstream end part of the filter tube section, there is likely to cause that the dust which has caused the clogging cannot be peeled off easily by the clogging of the downstream end part of the filter tube section. Therefore, as well as in this case, the cause for the clogging of the mesh (net) of the filter tube section (net filter F2) can be evaded as similar to the filter tube section which is in the circular cone shape, by providing the part where the dust flows into the filter tube section and within them at the periphery part that goes substantially straight hits the filter tube section as the non-mesh section.

Also in the third embodiment of the present invention, the dust separation section60is formed in the circular cone shape that diminishes its diameter gradually as going to the downstream direction. According to this structure, because the diameter of the filter tube section (net filter F2) is gradually decreased as going linearly from the upstream end to the downstream end, the wind that goes to the side of the mesh (net) of the filter tube section (net filter F2) without going straight through the passage61in the filter tube section becomes easier to attach the entire surfaces of the filter tube section (net filter F2) equally. Moreover, this wind (air) contains the relatively light dust, and this light dust hits the entire surfaces of the filter tube section (net filter F2) equally and is adapted to be captured by the net filter F2. It is in such a circumstance that the light dust can easily be peeled off since the light dust has less inertia energy and therefore it will not break into the mesh (net) of the net filter F2strongly.

In addition, in the third embodiment of the present invention, the filter tube section (net filter F2) and the non-mesh tube section (frame section W2) are constituting the tubular filter62and the diameter d1of the side of the air inflow opening (one end opening62A) of the tubular filter62is formed larger than the diameter d2of the air inflow opening (suction opening52), and the diameter d3of the downstream end (other end opening62B) of the tubular filter62is formed smaller in diameter than the diameter d2of the air inflow opening (suction opening52) and the diameter d4of the upstream end of the non-mesh tube section (frame section W2) is formed larger than the diameter d2of the air inflow opening (suction opening52).

According to this structure, the light dust that flows into the filter tube section (net filter F2) is captured by means of the filter tube section (net filter F2). It is in such a state that the light dust can easily be peeled off since the inertia energy of the light dust is less and therefore it will not break strongly into the mesh (net) of the filter tube section. Also, within the dust contained in the wind (air), although the dust that is flown from the suction opening52to the passage61and within them at the periphery area and the one that goes substantially straight by the inertia force caused when flowing out from the suction opening52into the passage61which is inside of the filter tube section has the large inertia energy, this dust hits the wide ranged non-mesh section (frame section W2) without hitting the net filter F2, therefore the cause for the clogging of the mesh (net) of the filter tube section (net filter F2) can be evaded.

As described above, according to this invention, the loss of air passage can be made small and the amount of wind does not decrease even if the dust accumulates, and the dust attached to the dust separating means which is for separating the dust from the air can be easily removed.

[Mode for Carrying Out the Invention 4]

FIGS. 16-18show an electric vacuum cleaner corresponding to the third embodiment of the present invention. The same reference numbers indicated inFIGS. 1-8are given for the parts identical or resembles to the composition of the embodiment shown inFIGS. 1-8, and their descriptions are omitted.

As mentioned above, the tubular filter62has the frame sections W1and W2which are in the round shape, the plurality of frame sections W3in stick shape which connect the frame sections W1and W2, and the filter F2in the mesh shape provided at the plurality of openings64which are formed by the each frame sections W1-W3(seeFIG. 17(a))

The openings64are provided equally throughout the entire circumference at the peripheral wall of the passage61, and the passage61is formed and surrounded by the frame sections W3and the filter F2.

The filter F2in the mesh shape stands for a filter formed by braiding fine threads in the mesh shape, and a large numbers of threads100are braided in such a manner that are folded mutually as shown inFIG. 18. The filter F2is formed in the tubular shape in such a manner as to surround the plurality of openings64integrally, and is provided at inner surface of the plurality of frame sections W3which the frame sections W1and W2are connected (seeFIG. 17(b)).

In addition, an opening O of the filter F2is formed so that it becomes gradually finer within the range of 110 μm to 30 μm as going from the upstream side of the passage61to the downstream side of the passage61, and the coarseness of mesh of the filter F2becomes gradually finer. In addition, here, the opening O of the filter F2which is proximity to a part contacted with the frame section W1is at least 110 μm, and the opening O of the filter F2which is proximity to a part contacted with the frame section W2is 30 μm.

Here, the “upstream side” stands for the side that the air is sucked and flows-in when the motor fan33is activated, more specifically, the side of the suction opening52of the container case body53. The “downstream side” stands for the side that the air is sucked and flows out when the motor fan33is activated, more specifically, the side of the intake opening33A of the motor fan33. Furthermore, the opening O stands for the mesh aperture, that is, a width between the thread100and the thread100(seeFIG. 18).

Here at, the surface finishing is applied onto the filter F2for reducing the friction resistance. For the surface finishing, there are, for example, the sputtering process, the fluoric coating and Teflon (registered trademark) coating.

Next, an operation of the electric vacuum cleaner constituted as above will be described hereinafter.

As mentioned above, the dust on a cleaning surface is sucked with the air in the passage61of the tubular filter62of the dust separation section60by activating the motor fan33. The air sucked to the passage61is sucked to the negative pressure room section56of the container case body53through the net filter F2of the openings64of the tubular filter62, and further sucked by the intake opening33A of the motor fan33through the filter80loaded at the opening51of the container case body53.

Also, some of the air is adapted to be introduced inside of the dust collection room section55through the strike section63and the guide pipe70, and introduced air turns into spiral flow by the guide wall G of the dust collection room section55, then flows into the negative pressure room section56through the ventilation opening59.

On the other hand, the dust that is sucked to the passage61of the tubular filter62and that has more weight than a predetermined weight goes straight through the passage61by an action of the inertia force because the passage61extends linearly to the longitudinal direction, and hits to the strike wall section63B of the strike section63, then introduced inside of the dust collection room section55by the guide pipe70. Then, the dust introduced inside of the dust collection room section55is adapted to be accumulated as it is compressed by the spiral flow of the air that likewise flows into the dust collection room section55.

Furthermore, the dust that is microscopic and light in weight sucked to the passage61of the tubular filter62flows with the air that passes the openings64without going straight through the passage61.

As just described, the dust and the air are separated by means of the dust collection room section60.

Here, as the mesh shaped filter F2is provided at the openings64which is located at the peripheral wall of the passage61, even if the dust flows with the air that passes the openings64, the dust can be captured by means of the filter F2. In addition, it becomes capable of separating the air and the dust efficiently.

Also, even if the dust is lifted into the air again by the spiral flow generated when introduced into the dust collection room section55, the air and the dust are each separated by the net filter F1provided at the ventilation opening59and the filter F2provided at the openings64, therefore an efficiency in separation can be enhanced.

In addition, as the wind velocity at the upstream side of the passage61is fast and therefore the dust goes relatively straight, the opening O of the filter F2can be created larger. Here, because the opening O is formed in such that it becomes finer as going from the side of the suction opening52as the upstream side of the passage61to the side of the intake opening33A as the downstream side of the passage61, the opening O of the filter F2is coarse at the side of the suction opening52, therefore the permeability at the side of the suction opening52of the passage61improves and efficiency in suction of air can be improved.

Meanwhile, it is difficult for the dust to go relatively straight due to the deterioration in the wind velocity at the side of the intake opening33A which is the downstream side of the passage61. But in the opening O of the filter F2, the side of the intake opening33A of the passage61is formed fine and can capture the fine dust that flows with the air unfailingly without allowing it to pass. Also, because the opening O is fine and so that a friction is large, therefore the permeability at the side of the intake opening33A can be suppressed and it is possible to make the fine dust difficult to flow.

Furthermore, because the opening O of this filter F2is adapted to be finer as going to the direction from the upstream side of the passage61to the downstream side, the flow of air passing the passage61becomes smoother and the clogging of the filter F2can be made difficult to occur.

Like stated, the electric vacuum cleaner in the present invention has the dust separation section60provided in the air passage which is leading from the suction opening52of the vacuum cleaner main body20to the intake opening33A of the motor fan33for separating the dust from the air that are sucked together from the suction opening52, and a dust collection room section (dust collection section)55provided in the air passage for collecting the dust that are separated by the dust separation section60. In addition, the dust separation section60has the one end opening62A that is communicated with the suction opening52and the tubular shaped passage (air passage)61which the other end opening62B is communicated with the dust collection room section55, and the openings64which are provided at the peripheral wall of the passage61. Furthermore, the mesh shape filter F2is provided at the openings64.

By this structure, it is possible to separate the dust and the air without generating spiral flow at inside of the passage61of the tubular filter62which is the dust separation section60. Therefore, the separation can be done in efficient manner and the improvement of separating efficiency can be made. Also, by this structure, the deterioration in sucking efficiency can be avoided as the loss of air passage within the passage61becomes small.

Additionally, the fine dust can be captured by the mesh shaped filter F2which is provided at the openings64when the dust and the separated air pass from the passage61of the tubular filter62to the openings64and sucked to the negative pressure room section56of the container case body53.

Furthermore, because the opening O of the filter F2is made finer as going from the upstream side to the downstream side of the passage61, a sufficient permeability can be obtained at the upstream side of passage61and the deterioration in the sucking efficiency can be avoided. In addition, the fine dust can be unfailingly captured at the downstream side of the passage61and it is possible to separate the dust and the air in efficient manner as well as it is possible to separate the dust and the air sufficiently.

Additionally, because the size of the opening O of the filter F2is formed within the range of 110 μm to 30 μm, the opening O at maximum becomes 110 μm, therefore it is possible to obtain enough permeability in an extent that the dust sucked inside of the passage61does not closely contact with the filter F2. Furthermore, the opening O at minimum becomes 30 μm, therefore it is possible to obtain a necessary permeability while capable of unfailingly capturing the fine dust which is flowing with the air, therefore it is possible to improve the separating efficiency.

Also, because the surface finishing for reducing the friction resistance is applied on the surface of filter F2, the dust becomes difficult to be hooked at the surface of filter F2and the occurrence of the early clogging can be avoided.

Particularly, when the surface finishing is the sputtering process, clogging can be avoided even more as metallic atoms are equally attached on the surface of filter F2and the friction resistance can be reduced exceedingly.

By the way, because the filter F2is provided at the inner surface of the frame sections W3, the circumstance that the dust sticks on the frame sections W3can be avoided, and clogging being difficult to occur.

As described above, according to the electric vacuum cleaner of the present invention, it is possible to improve the separating efficiency by separating the dust and the air efficiently.

[Mode for Carrying Out the Invention 5]

As described above, although one embodiment relating to the present invention has been described with reference to the accompanying drawings, the present invention is not limited to the specific embodiments as described above, the modifications of design or the like are included in the present invention without departing from the scope of the present invention.

For example, in the embodiment mentioned above, although the opening O of the mesh shaped filter F2is formed gradually finer as going from the suction opening52side to the intake opening33A side, it may be also recommendable to set the opening O finer in step-by-step way as shown inFIG. 19.

In this instance, for example, at first, separate between the frame section W1and the frame section W2with intermediate frame sections W4and W5, and provide a filter F21which has the opening O of for example, 110 μm between the frame section W1and the intermediate frame section W4, and a filter F22which has the opening O of for example, 70 μm from the intermediate frame section W4to the intermediate frame section W5, and a filter F23which has the opening O of for example 30 μm between the intermediate frame section W5and the frame section W2. By this, it becomes easier to constitute the filter so as to make the opening O finer in the step-by-step way. As well as in this case, it is possible to avoid the dust to be stuck to the frame sections W3-W5by providing each filter F21-F23to inner surface of the frame sections W3,W4and W5.

As mentioned above, according to the electric vacuum cleaner in the present invention, it is possible to improve the separating efficiency by separating the dust and the air efficiently.

[Mode for Carrying Out the Invention 6]

FIGS. 20-23show an electric vacuum cleaner corresponding to the third embodiment of the present invention. The same reference numbers indicated inFIGS. 1-8are given for the parts identical or resembles to the structure of the embodiment shown inFIGS. 1-8, and their descriptions are omitted.

In the motor-driven section34of the main body case30, a battery39is loaded at a down side of the motor fan33as shown inFIG. 20. The battery39provides electric power to the motor fan33. Additionally, it is possible to provide the electric power of a commercial alternating current to the motor fan33or the like through a cord reel by substituting the battery39shown in the figure with the cord reel and arranging the cord reel at the same part.

As shown inFIG. 20andFIG. 21, the container case body53has the dust collection room section (dust accumulating section)55which is formed at a lower part of the case body53, the negative pressure room section (negative pressure space)56formed mainly at an upper part of the dust collection room section55, a first dust separation section60provided at inside of the negative pressure room section56, and the strike section63as a guiding section which is leading the dust separated by the dust separation section60to the dust collection room section55.

The bottom face of the dust collection room section55is opened. The bottom plate57is attached to the bottom part of the dust collection room section55capable of opening and closing in about the axis J, and it is possible to dispose the dust accumulated in the dust collection room section55by opening the bottom plate57. The closed state of the bottom plate57is adapted to be released through a mechanism which is not shown in the figure that is operated simultaneously by the press-in operation of a control button provided on the handle section54.74denotes a circular shaped seal which is fixed at an inner surface of the bottom plate57and thereby air tightness at a lower end part of the dust collection room section55is provided when the bottom plate57is in closed condition.

The suction opening52is formed at an upper part of the front wall53aof the dust collection case50as an opening for a sucking use. Also, the dust collection case50has a rear side wall (first wall)55A of the dust collection room section55near to the rear part of the opening51, and the top panel (second wall)58which is continuously bent from the upper end of the rear side wall55A to the front wall53a. The top panel58and the rear side wall55A divide the lower part's dust collection room section55and the upper part's negative pressure room section56. At the top panel58which constitutes a ceiling wall of the dust collection room section55, the ventilation opening59is formed that communicates the dust collection room section55with the negative pressure room section56.

The ventilation opening59is provided such that the ventilation opening59substantially faces a center of the dust collection room section55. By this, the ventilation opening59faces to the filter F2of the first dust separation section60which will be described later from a lower part of it. The filter F1which is made from a net for example and which is attached to the ventilation opening59.

The mesh of the filter F1is 30 μm-110 μm, preferably 60 μm-80 μm. By the filter F1, it is possible to avoid the dust which has more size than predetermined size to flow into the negative pressure room section56, as well as facilitating the maintenance for removing the dust clogged at the filter F1.

The connection hole58A is formed at the side of the wall60aof the top panel58. At lower part of the connection hole58A, there is provided the guide wall G to generate spiral flow at inside of the dust collection room section55.

The first dust separation section60constitutes an inertia separation device which is in a direct advancing flow type for separating the air and the dust by inertia-separation effect, and has the tubular filter62which forms the tubular passage61as a separation air passage, and has the strike section (guiding section)63.

The tubular filter62as an air passage body has the tubular frame W which is for example, in a hollow cone shape in which one end and an other end are both opened and has the plurality of openings (separation opening)64as the air guiding opening at its entire circumference in a regular interval, and has the filter F2for blocking the openings64of the tubular frame W. To say in detail, the tubular frame W, the tubular filter62, is constituted by a small and large pair of round frame sections W1and W2and the plurality of ribs W3which connect the frame sections W1and W2. The respective openings64are formed by spaces surrounded by the both frame sections W1, W2and W3. The filter F2is made by the net for example, and is attached along the inner periphery surface of aforementioned frame in a tubular shape.

Therefore, the tubular filter62constitutes a structure as if both sides in an axial direction of a mound are opened, and the tubular shaped passage61is formed which is surrounded by the tubular filter62. It is recommendable to provide aforementioned ventilation opening59at least near to the small diameter part of the tubular filter62in a facing manner.

This tubular shaped passage61extends linearly to the axial direction (to the longitudinal direction in the present embodiment) of the vacuum cleaner main body20. The tubular shaped passage61is communicated with the intake opening33A of the motor fan33subsequently through the openings64of the tubular filter62, the negative pressure room section56of the container case body53and the opening34A of the motor-driven section34of the main body case30.

The diameter of the one end opening62A which is a large diameter of the tubular filter62is formed larger than the diameter of the suction opening52of the container case body53. The tubular filter62is connected to the container case body53so that the suction opening52falls within the one end opening62A. The diameter of the other end opening62B which is a small diameter of the tubular filter62is formed virtually the same diameter of the suction opening52. By this, the diameter of the tubular filter62is gradually decreasing as going from the one end to other end linearly. By the way, it may be recommendable that the diameter of the other end opening62B of the tubular filter62is smaller than the diameter of the suction opening52.

An axis line of the tubular filter62and an axis line of the connection pipe44of the lid body40continue virtually in alignment, and the intake opening33A of the motor fan33is provided in such a manner as to face on these extending axes. The connection pipe44of the lid body40, the suction opening52of the container case body53, the tubular filter62, the opening51of the container case body55and the intake opening33A of the motor fan33are subsequently arranged along the axial direction (the longitudinal direction in the present embodiment) of the vacuum cleaner main body20at virtually the same height position.

The strike section63is provided continuously at the other end opening62B of the tubular filter62. To say in detail, the strike section63has the slant wall section63A extending from the upper side of the other end opening62B of the tubular filter62to the lower side on a slant, and the strike wall section63B (wind striking wall section) which faces to the other end opening62B of the tubular filter62and is also incurved from the one end of the slant wall section63A and extending to the lower part, and the side wall section63C which is formed at both sides of the slant wall section63A and the strike wall section63B. Additionally, the strike section63has the opening63D which is jointed to the other end opening62B of the tubular filter62.

A lower part of the strike section63constitutes a tubular shape and which is for example, extending in a vertical direction and covering the connection hole58A, and is also connected throughout the ceiling wall58and the uprising wall60a. By this connection, the strike section63communicates the tubular shaped passage61with the dust collection room section55.

This uprising wall60ais provided slightly inside (front side) than the opening51of the container case body53, and giving a predetermined depth H to the opening51. The filter80which constitutes the second dust separation section is attachably and detachably loaded inside of the opening51by using the depth H (seeFIGS. 20,21and23).

The filter80is provided with a filter frame81and a filter element82which is loaded in such a manner as to block entire inner side of the frame81. The filter element82is constituted by making the filter medium in a mat shape, and particularly in the present embodiment, a pleat-shaped filter element is used which the pleat process is applied for expanding the filter element82in a thickness direction thereof. The mesh of this filter element82is finer than the mesh of filters F1and F2which are at a former step.

Next, an operation of the electric vacuum cleaner constituted as above will be described.

As mentioned above, by actuating the motor fan33, the partial air sucked to the tubular shaped passage61is sucked by the negative pressure room section56of the container case body53through the first filter F2of the openings64of the tubular filter62, and further sucked by the intake opening33A of the motor fan33through the filter80which is loaded on the opening51of the container case body53.

In this sucking of the air, the dust which has more weight than a predetermined weight and which is sucked to the tubular shaped passage61that extends straight in a longitudinal direction of the vacuum cleaner main body20cannot be passed through the openings64by changing its direction suddenly because of its inertia. Consequently, aforementioned dust which has weight is adapted to be separated from the air that passes the openings64, and goes straight through the tubular shaped passage61, and then hits to the strike wall section63B of the guiding section63and is introduced into the dust collection room section55along the strike section63.

Some of the air is adapted to be introduced into the dust collection room section55through the strike section63as similar to aforementioned dust which has the more weight. The introduced air as just stated then becomes spiral flow by the guide wall G in a downward direction which revolves along the inner peripheral surface of the dust collection room section55. Consequently, the dust introduced into the dust collection room section55is adapted to be accumulated as it is compressed along the lower inner peripheral surface of the dust collection room section55by aforementioned spiral flow.

The air turned into the spiral flow by being introduced inside of the dust collection room section55is reversed and drifted upward at a center part in the dust collection room section55, and goes through the ventilation opening59of the dust collection room section55and is sucked by the negative pressure room section56of the container case body53, and further goes through the filter80which is loaded on the opening51of the container case body53and is sucked by the intake opening33A of the motor fan33.

In this case, since the ventilation opening59is provided at the wall58in such a manner as to face virtually the center part of the dust collection room section55, it is less likely that the dust within the dust collection room section55attaches to the filter F1of the ventilation opening59. Moreover, the air sucked to the intake opening33A from the dust collection room section55through the ventilation opening59flows the negative pressure room section56via outer peripheral surface of the filter F2which is in a hollow cone shape by a positional relationship between the ventilation opening59and the dust separation section60, or to be more precise, the air flows the negative pressure room section56while blowing the filter F2from the lower direction of the filter F2.

At the same time, because the light weighted dust flows with the air that goes through the filter F2of the openings64by an intake negative pressure of the motor fan33without going straight through the tubular shaped passage61which is in the tubular filter62of the dust separation section60, the dust becomes attached to the inner peripheral surface of filter F2. If the clogging of the filter F2caused by the attachment of the light weighted dust becomes larger, the amount of wind that goes through the filter F2reduces. But the negative pressure of the negative pressure room section56increases corresponding to the amount it reduced as well as the negative pressure within the dust collection room section55through the ventilation opening59of the first wall58. Consequently, the wind velocity and the amount of wind of the air that goes straight through the tubular shaped passage61increase.

As stated above, even if the amount of wind that passes through the filter F2is reduced by clogging, the amount of wind the motor fan33sucks can be maintained substantially constant because the amount of wind goes straight through the passage61increases. Therefore, it is always possible to suck the dust by the predetermined sucking power with irrespective of the clogging of the filter F2.

Moreover, if the wind velocity that goes straight through the tubular shaped passage61becomes larger as above mentioned, the air that goes straight becomes easier to peel off the dust attached to the filter F2. On this occasion, because the diameter of the tubular shaped air passage body62gradually decreases as going from the upstream side's opening62A to the downstream side's opening62B, the air that goes straight through the tubular shaped passage61hits equally to entire surfaces of the filter F2and flows as gravitated toward the center part of the tubular shaped passage61. Therefore the air becomes easier to peel off the dust attached to the inner surface of the filter F2.

In addition, because the air trying to reach the intake opening33A of the motor fan33from the dust collection room section55through the ventilation opening59hits the outer peripheral surface of the filter F2as already mentioned, the air becomes easier to peel off the dust attached to the inner surface of the filter F2.

To say in detail, because the dust attached to the inner surface of the filter F2is influenced by a force pulling toward an outside direction by the negative pressure caused by the negative pressure room section56and a transferring force caused by the air passing the tubular shaped passage61, particularly a relatively long dust and a membranous dust which became equivalent to a relatively long condition substantially by a development of the attachment to the inner surface of the filter F2, are easier to stop at its current position while maintaining an unstable attached condition at the inner surface of the filter F2by an antagonism of aforementioned two forces. If there is retention of the dust at the inner surface of the filter F2as such, the dust attachment develops easily from there as a center. In addition, the velocity of the dust contained air that tries to penetrate the hollow cone shaped filter F2in a longitudinal direction becomes slow as going to a side of the small diameter part of the tubular filter62which the filter F2is attached to the inner peripheral surface, therefore the dust attaches easily to the inner surface of it.

However, since the force trying to pull the dust attached to the inner surface of the filter F2by the negative pressure of the negative pressure room section56can be weakened in that area where the air hits by the air hitting the outside of the filter F2, a superiority in aforementioned transferring force can be made by breaking a balance of aforementioned forces. By this, the dust attached to the inner surface of filter F2can be peeled off easily even more. In addition, because the ventilation opening59faces to the small diameter part of the tubular filter62and the air hits at least outside of the side of the small diameter part of the filter F2, it is possible to remove the dust attached to an inner surface of the small diameter part effectively.

In addition to this, in the area where the air hits outside of the filter F2, since the force trying to pull the air in the filter F2outside by the negative pressure of the negative pressure room section56can be weakened, it is possible to reduce and restrain the attachment of the dust to aforementioned area.

Furthermore, since it is structured that the air passed the ventilation opening59hits from the lower part of the filter F2, even if it is the dust that is attached to the lower part of the inner surface of the filter F2, it is possible to peel off effectively as already mentioned.

The dust that is peeled off from the inner surface of the filter F2as stated above is adapted to be introduced into the dust collection room section55through the strike section63as similar to the heavy weighted dust, and is separated from the air centrifugally in the dust collection room section55and is accumulated.

In addition, in the dust separation room section60, because the dust is separated from the air by using the inertia force caused by the heavy weighted dust such as coarse dust trying to move forward rather than swirling the dust contained air and centrifugally separating the dust and the air while reversing the moving direction of the spiral flow, the loss of air passage becomes less in the dust separation section60. Moreover, because the suction opening52, the separation air passage62a, the opening51of container case body53and the intake opening33A of the motor fan33are virtually at the same height position and are arranged in order continuously in the longitudinal direction, the main flow of the air does not change significantly as shown representatively by the arrow Q inFIG. 3, and flows substantially straight forward at almost the same height position when the air is sucked to the negative pressure room section56of the container case body53through the filter F2from the tubular shaped passage61, and is sucked by the motor fan33.

Consequently, the loss of air passage becomes even less, which the performance of the motor fan33can be achieved sufficiently. Furthermore, because the connection pipe44of the lid body40and the tubular shaped tubular filter62are arranged in a straight line, the direction of the air introduced to the suction opening52of the container case body53and the extending direction of the tubular filter62become substantially in alignment, therefore its loss of air passage becomes even more less.

As mentioned, because the air inside of the negative pressure room section56passes the filter80and sucked by the motor fan33, the microscopic dust passed the filters F1and F2can be captured by the filter80, and the motor fan33can suck the cleaned air cleaned by them.

Furthermore, in the cleaning operation as described above, at an upstream side of the filter80which is for separating the dust by the percolation, the dust separation section60which is for separating the dust by the inertia separating effect is arranged, so that the coarse dust or the like is separated at the dust separation section61beforehand. By this, it is possible to avoid the filter80to be as an apparent clogged condition at an early stage due to the attachment of the large dust at the filter80that is supposed to be removed at the dust separation section60.

The present invention is not limited by aforementioned one embodiment. For example, it may be also recommendable to provide the tubular filter62in a straight pipe shape such as a circular cylinder or an angular pipe, and the filter F1of the aforementioned one embodiment can be omitted, and in the dust collection room section55, it is also possible to omit the guide wall G which is for creating the spiral flow. In addition, the filter80which constitutes the second dust separation section in aforementioned one embodiment can also be detachably sustained at the main body case30and can be fixed into the opening51which is provided at the container case body53of the dust collection case50in connection with attaching the dust collection case50to the main body case30.

As described above, according to the present invention, it is possible to provide the electric vacuum cleaner in which the loss of air passage can be reduced compared with the one that carries out the cyclone type separation, and the deterioration in the amount of wind can be suppressed easily even if the dust accumulates at the dust separation section.

[Mode for Carrying Out the Invention 6]

FIGS. 24 and 25show an electric vacuum cleaner corresponding to the sixth embodiment of the present invention. The same reference numbers indicated inFIGS. 1-8are given for the parts identical or resembles to the structure of the embodiment shown inFIGS. 1-8, and their descriptions are omitted.

In the sixth embodiment of the present invention, it is constituted that when the wind velocity going straight of the passage61of the tubular filter62increases, the air going straight through the passage peels off the dust attached to the net filter F2. On this occasion, as an angle α between a peripheral wall62S and a center line L of the tubular filter62is set virtually 30 degrees, the wind going straight through the passage61hits the entire surface of the net filter F2equally, and the wind becomes easier to flow along the surface of the net filter F2, consequently the dust attached to the net filter F2becomes easier to be peeled off.

Next, operation on the electric vacuum cleaner constituted as above mentioned will be described hereunder.

By actuating the motor fan33in such a manner as mentioned above, the air sucked to the passage61is adapted to be sucked by the negative pressure room section56of the container case body53through the net filter F2of the openings64of the tubular filter62, and is further sucked by the intake opening33A of the motor fan33through the filter80which is loaded on the opening51of the container case body53.

Meanwhile, because the passage61extends linearly to the longitudinal direction, the dust which is sucked to the passage61of the tubular filter62and which has more weight than predetermined weight goes straight through the passage61by the inertia and is introduced inside of the dust collection room section55by the guide pipe70. That is to say, the dust and the air are separated by the dust separation section60.

Also, some of the air is adapted to be introduced inside of the dust collection room section55through the guide pipe70, and the introduced air then turns into spiral flow by the guide wall G of the dust collection room section55, and the dust introduced inside of the dust collection room section55is accumulated by the spiral flow as it is compressed.

The air that is introduced into the dust collection room section55is, when it is turned into spiral flow, sucked into the negative pressure room section56of the container case body53through the ventilation opening59of the top panel58of the dust collection room section55.

As the light weighted microscopic dust flows with the air that goes through the net filter F2of the openings64without going straight through the passage61of the tubular filter62, the dust becomes attached to the net filter F2. Although the amount of wind that goes through the net filter F2reduces by the attachment of the microscopic dust to the net filter F2, the negative pressure of the negative pressure room section56of the container case body53increases corresponding to the amount it reduced as well as the negative pressure within the dust collection room section55through the ventilation opening59of the top panel58. Consequently, the wind velocity of the air that goes straight through the passage61of the tubular filter62becomes greater, therefore the amount of wind going straight increases.

When the wind velocity that goes straight through the passage61of the tubular filter62become greater, the air that goes straight peels off the dust attached to the net filter62. On this occasion, as the angle α between the peripheral wall62S and the center line L of the tubular filter62is set virtually 30 degrees, the wind going straight through the passage61hits the entire surfaces of the net filter F2equally, and the wind becomes easier to flow along the surface of the net filter F2, consequently the dust attached to the net filter F2becomes easier to be peeled off.

By the way, if the degrees of the angle α between the peripheral wall62S of the tubular filter62and the center line L of the tubular filter62becomes larger, the amount of dust attaching the net filter F2increases because the amount of wind Q hitting the net filter F2equally increases as shown inFIG. 25. Also, the amount of wind Q′ flowing along the net filter F2as shown by the chained line decreases. Consequently, the attached dust becomes harder to be peeled off from the net filter F2by the wind Q′, only the amount of dust attaching to the net filter F2increases.

But when the angle α becomes less than 45 degrees, the amount of dust that attaches to the net filter F2can be decreased because of the amount of wind Q hitting equally to the net filter F2decreases, and furthermore, because the amount of wind Q′ flowing along the net filter F2increases, it becomes preferable that the wind Q′ becomes peeling off the dust attached to the net filter efficiently.

If the angle α becomes too small, the amount of dust attaching to the net filter F2decreases significantly because the amount of wind Q hitting equally to the net filter F2decreases significantly, but the amount of wind Q hitting equally to the net filter F2becomes subtle, therefore the amount of wind Q′ flowing along the net filter F2decreases significantly. Consequently, the dust attached to the net filter F2becomes harder to be peeled off by the wind Q′.

Therefore, when the angle α is at virtually 30 degrees, it is possible to reduce the amount of dust attached to the net filter F2as well as increase the amount of wind Q′ that is flowing along the net filter F2, thereby it becomes most preferable that the dust attached to the net filter F2can be peeled off in most effective manner.

The peeled dust is then introduced and accumulated inside of the dust collection room section55through the guide pipe70.

According to the invention as described above, even if the dust attaches to the net filter, the attached dust can be removed efficiently by the air that flows in the air passage.

[Mode for Carrying Out the Invention 7]

FIGS. 26-33show an electric vacuum cleaner corresponding to the seventh embodiment of the present invention. The same reference numbers used in above mentioned embodiment of the invention are given for the parts identical or resembles to the structure of the above mentioned embodiment of the invention, and their descriptions are omitted.

InFIG. 26,20is the vacuum cleaner main body, and the one end of the hose21is connected attachabley and detachably to the vacuum cleaner main body20and the hand operating pipe22is provided on its other end. The extension pipe23is connected attachably and detachably to the hand operating pipe22and the suction opening body24is connected to the end of the extension pipe23attachably and detachably. Also, the control section22A is provided on the hand operating pipe22, and there is provided on the control section22A the control switch which is not shown.

As shown inFIGS. 27 to 29, the vacuum cleaner main body20is comprised of the main body case30and a dust collection case (dust cup)50which is attachably and detachably mounted on the main body case30and the lid body40capable of opening and closing in a vertical direction with the back end of the lid body40being connected to the main body case30by the hinge connection.

The main body case30has a cord reel room36which is formed at a lower part and installed with a cord reel CR and has the motor-driven room34which is loaded with the motor fan33and formed above the cord reel room36. At front side of the cord reel room36, there is provided the mounting section35which is in the plate shape that protrudes to the forward direction. Onto the mounting section35the dust collection case50is attachably and detachably mounted. Furthermore, the dust collection case50is adapted to be fixed by a hold of the lid body40and the mounting section35when the lid body40is closed.

Also, the front side of the motor-driven section34of the main body case30is made opened, and this opening34A faces and is communicated with the intake opening (intake vent)33A of the motor fan33. At both side faces of the main body case30, the plurality of exhaust holes38are formed. These exhaust holes38are communicated with the exhaust opening33B of the motor fan33through the exhaust air passage which is not shown, and the air exhausted from the exhaust opening33B of the motor fan33is exhausted outside from the exhaust holes38through the exhaust air passage.

To the lid body40, the connection pipe44which has the connection opening43at the front end of the connection pipe44which is attachably and detachably connecting the dust collection hose21, is provided. The connection pipe44is extended in a longitudinal direction and its rear end has an opening45A.

As shown inFIG. 30toFIG. 32, the dust collection case50has the opening51on the rear face (right side inFIG. 31) and a case body53which has a front side opening (case opening)50aat the front face, and the handle section54which is integrally formed at the case body53.

The case body53has the dust collection room section (dust collection section)55formed at the lower part, the negative pressure room section56formed at above the dust collection room section55, the dust separation section60provided within the negative pressure room section56and the guide pipe70for guiding the dust separated at the dust separation section60to the dust collection room section55.

The front side opening50aof the case body53is closed by means of an opening and closing lid90. On a back of the opening and closing lid90, a seal member91is fixed which attaches to a peripheral part of its front side opening50a. The seal member91seals between the front side opening50aand the opening and closing lid90.

To the opening and closing lid90, a communicating pipe92is provided which is communicated with the connection pipe44of the lid body40, and an opening92A which is located at a front end of the communicating pipe (suction opening)92is jointed with the opening45A of the connection pipe44, and the communicating pipe92is communicated with the passage61of the dust separation section60through the front side opening50a. Above the opening and closing lid90, a pair of arms93(only one is shown) are provided extending in a backward direction (rightward direction inFIG. 30), and an axis P is provided at end of the arms93that extends in right and left direction (the direction perpendicular to a page space inFIG. 33). The axis P is rotatably fixed to an upper part of the case body53.

In addition, the opening and closing lid90opens the front side opening50aof the case body53by rotating about the axis P as a center as shown inFIG. 33. In other words, the opening and closing lid90operates the opening and closing movement by rotating about the axis P as the center.

Next, an operation of the electric vacuum cleaner constituted as above will be described hereinafter.

First, as shown inFIG. 29, the dust collection case50is mounted on the mounting section35of the main body case30and the lid body40is closed, and the hose21is connected to the connection opening43of the lid body40. When operating the switch of the control section22A which is not shown, the motor fan23actuates. By the actuation of the motor fan23, the negative pressure room section56of the case body53becomes negative pressure through the openings34A of the main body case30. This negative pressure acts upon the openings64of the tubular filter62, the passage61of the tubular filter62, the front side opening50aof the case body53, the communicating pipe92of the opening and closing lid90, the connection pipe44of the lid body40, the hose21, the extension pipe23and the suction opening body24, thereby the dust is sucked together with the air from the suction opening body24.

The sucked dust and air are sucked toward the connection opening43of the lid body40through the extension pipe23and the hose21. The dust and the air that are sucked to the connection opening43are sucked toward the passage61of the tubular filter62of the dust separation section60through the connection pipe44of the lid body40, the communicating pipe92of the opening and closing lid90and the front side opening50aof the case body53.

When cleaning the dust attached to the net filter F2of the dust separation section60, first, the lid body40is opened as shown inFIG. 28and the dust collection case50is dismounted from the mounting section35of the main body case30. Then, the opening and closing lid90of the case body53of the dust collection case50is opened and the front side opening50aof the case body53is opened as shown in cross-section inFIG. 33. By this opening operation, it is possible to put fingers or the like from its front side opening50aso that the dust attached to the net filter F2can be rubbed off by the fingers or the like, therefore the cleaning of the net filter F2becomes ever so easy. Furthermore, it can be cleaned even more if the whole dust collection case50is wet-cleaned. Like so, the cleaning of the net filter of the dust separation section becomes very easy to be cleaned.

As described above, the electric vacuum cleaner according to the embodiment of the present invention, the dust separation section60is provided at the suction air passage which is leading from the suction opening (connection opening43or suction opening52, suction opening100) of the vacuum cleaner main body20to the intake opening (33A,107A) of the motor fan (33,107) to separate the dust sucked from the suction opening (connection opening43or suction opening52, suction opening100) with the air and the dust collection section (dust collection room section55, dust collection room104) provided at the suction air passage for collecting the dust separated from the air at the dust separation section60.

In addition, the dust separation section60of this electric vacuum cleaner has the tubular passage (passage61) which the one end communicates with the suction opening (connection opening43or suction opening52, suction opening100) so that the dust sucked from the suction opening (connection opening43or suction opening52, suction opening100) flows in and the other end communicates with the dust collection section (dust collection room section55, dust collection room104), and the air guiding opening (openings64, openings102H) provided at the peripheral wall of the tubular passage (passage61) and is communicated with the intake opening (33A,107A) of the motor fan (33,107).

Generally in the conventional electric vacuum cleaner with the cyclone system, because the air swirls round and then reversed and drifted upward and sucked, the loss of air passage of the air is large (i.e., loss in an amount of air passing through is large). Also in the conventional electric vacuum cleaner with the paper package as the paper filter, when the predetermined amount of dust is accumulated in the paper package, the amount of air decreases easily. On the contrary, in the electric vacuum cleaner of the present embodiment, as the dust sucked with the air goes straight by inertia and is collected, and the air is sucked by the motor fan (33,107) through the air guiding opening (openings64, openings102H), the air and the dust are separated without generating spiral flow, therefore the loss of air passage becomes less.

Also, the electric vacuum cleaner according to the embodiment of the present invention, the dust separation section60is provided at the suction air passage leading from the suction opening (connection opening43or suction opening52, suction opening100) of the vacuum cleaner main body20to the intake opening (33A,107A) of the motor fan (33,107) to separate the dust sucked from the suction opening (connection opening43or suction opening52, suction opening100) with the air and the dust collection section (dust collection room section55, dust collection room104) provided at the suction air passage for collecting the dust separated from the air at the dust separation section60.

Moreover, the dust separation section60of this electric vacuum cleaner has a dust guiding duct adapted to inflow the dust sucked from the suction opening (connection opening43or suction opening52, suction opening100) from the one end and for guiding the dust flows in from the other end to the dust collection section by the inertia force, and an air guiding air passage is provided to be communicated with the midstream of the dust guiding duct and is communicated with the intake opening (64,102H) of the motor fan (33,107) without passing through the dust collection section.

As well as in the electric vacuum cleaner of the present embodiment, as the dust sucked with the air goes straight by inertia and is collected, and the air is sucked by the motor fan (33,107) through the air guiding opening (openings64, openings102H), the air and the dust are separated without generating spiral flow, therefore the loss of air passage becomes less.

Also, the electric vacuum cleaner according to the embodiment of the present invention, the dust separation section60is provided at the suction air passage which is leading from the suction opening (connection opening43or suction opening52, suction opening100) of the vacuum cleaner main body20to the intake opening (33A,107A) of the motor fan (33,107) to separate the dust sucked from the suction opening (connection opening43or suction opening52, suction opening100) with the air and the dust collection section (dust collection room section55, dust collection room104) provided at the suction air passage for collecting the dust separated from the air at the dust separation section60.

Moreover, the dust separation section60of this electric vacuum cleaner has the tubular passage (passage61) which the one end is communicated with the suction opening (connection opening43or suction opening52, suction opening100) and adapted to flow in the dust sucked from the suction opening (connection opening43or suction opening52, suction opening100), and an air guiding air passage provided at the one end with the air guiding opening (openings64, openings102H) which is provided on the peripheral wall of the tubular passage (passage61) and the other end is communicated with the intake opening (openings64, openings102H) of the motor fan (33,107) without passing through the dust collection section (dust collection room section55, dust collection room104).

As well as in the electric vacuum cleaner of the present embodiment, as the dust sucked with the air goes straight by inertia and is collected, and the air is sucked by the motor fan (33,107) through the air guiding opening (openings64, openings102H), the air and the dust are separated without generating spiral flow, therefore the loss of air passage becomes less.

Also, the electric vacuum cleaner according to the embodiment of the present invention, the dust strike section (63,103) which is provided at the other end side of the tubular passage (passage61) and is provided for hitting the dust that flows into the tubular passage (passage61) and goes straight through it, and the dust collection section (dust collection room section55, dust collection room104) for collecting the dust being hit to the dust strike section (63,103) is provided at a lower part of the strike section63.

As well as in the electric vacuum cleaner of the present embodiment, as the dust sucked with the air goes straight by and is collected, and the air is sucked by the motor fan (33,107) through the air guiding opening (openings64, openings102H), the air and the dust are separated without generating spiral flow, therefore the loss of air passage becomes less. Furthermore, the dust does not fly up within the dust collection section (dust collection room section55, dust collection room104).

Also, the air guiding opening (openings64,102H) of the electric vacuum cleaner according to the embodiment of the present invention is provided throughout the entire circumference of the peripheral wall of the tubular passage (passage61).

As well as in the electric vacuum cleaner of the present embodiment, as the dust sucked with the air goes straight by the inertia and is collected, and the air is sucked by the motor fan (33,107) through the air guiding opening (openings64, openings102H), the air and the dust are separated without generating spiral flow, therefore the loss of air passage becomes less.

Also, a filter is provided at the air guiding opening (openings64,102H) of the tubular passage (passage61) of the electric vacuum cleaner according to embodiment of the present invention. According to this structure, because the light weighted dust (microscopic dust) does not go straight (difficult to be influenced by the inertia) to the dust strike section (strike section63) by the inertia force caused when sucked into the tubular passage (passage61) is sucked to the side of the motor fan33with the air through the air guiding opening (openings64, openings102H), it is possible to capture the light weighted dust at this occasion using the filter.

Also, the tubular passage (passage61) of the electric vacuum cleaner according to the embodiment of the present invention is provided with the filter tube section (net filter F2) as a tubular shaped filter in the mesh shape which is located at the upstream side, and a tube section (frame section W2) which is continuously built to the downstream side of the filter tube section and has non-permeability. According to this structure, although the light weighted microscopic dust that is difficult to be influenced by inertia is captured by the filter tube section (net filter F2) at the upstream side, it is hard to break into the mesh of filter (net filter F2) and it is easier to be peeled off. In addition, the dust influenced by inertia hits to the non-permeability tube section (frame section W2) at the downstream side since it is easier to go straight, so the dust influenced by inertia does not clog the filter (net filter F2).

Also, the filter (net filter F2) of the electric vacuum cleaner in the embodiment of the present invention is in the mesh shape, and the opening O of the mesh shape filter (net filter F2) is formed finer as going from the upstream side to the down stream side of the tubular passage. According to this structure, because the dust is easier to go straight since the wind velocity at the upstream side is fast, the permeability is increased at the upstream side by having the opening O of the mesh shape filter (net filter F2) to be wider, therefore it is possible to increase the sucking efficiency. Furthermore, at the downstream side of the tubular passage (passage61), because the opening O of the filter (net filter F2) is fine, the flow of air becomes smooth, therefore clogging of the filter (net filter F2) can be avoided.

Also, the filter (net filter F2) of the electric vacuum cleaner according to the embodiment of the present invention is in the mesh shape, and the surface finishing for reducing the friction resistance is applied on the filter (net filter F2). According to this structure, the dust is hard to be attached to the filter (net filter F2) since the surface finishing for reducing the friction resistance is applied on the filter (net filter F2).

Also, the diameter of the tubular passage (passage61) of the electric vacuum cleaner according to the embodiment of the present invention is gradually decreased from the one end to the other end direction linearly. According to this structure, the air (wind) going straight becomes easier to hit equally the entire surfaces of the air guiding opening (openings64) which is provided at the peripheral wall of the tubular passage (passage61), therefore the dust attached to the filter (net filter F2) is easily peeled off.

Also, the diameter of the one end opening62A of the tubular passage (passage61) of the electric vacuum cleaner according to the embodiment of the present invention is larger than the diameter of the suction opening52of the vacuum cleaner main body, and the diameter of the other end opening62B of the tubular passage is less than the diameter of the suction opening52of the vacuum cleaner main body. According to this structure, the air (wind) going straight becomes easier to hit equally the entire surface of the air guiding opening (openings64) which is provided at the peripheral wall of the tubular passage (passage61), therefore the dust attached to the filter (net filter F2) is easily be peeled off.

Also, the vacuum cleaner main body20of the electric vacuum cleaner according to the embodiment of the present invention is provided with the dust collection case50which has the dust separation section60and the dust collection section60. Furthermore, the tubular passage (passage61) of the dust separation section60is formed inside of the tubular filter62which is for separating the dust sucked from the suction opening (communicating pipe92) of the vacuum cleaner main body20, a diameter of a filter entrance opening of the tubular filter62is formed larger than the diameter of the suction opening (communicating pipe92) of the vacuum cleaner main body20, the case opening (front side opening50a) which faces to the filter entrance opening is provided at the dust collection case50, the opening and closing lid90for blocking the case opening (front side opening50a) is provided capable of opening and closing, and the suction opening of the vacuum cleaner main body20is provided at the opening and closing lid90.

According to this structure, the fingers or the like are difficult to put into the suction opening of the vacuum cleaner main body20, therefore by providing the side of the suction opening as being capable of opening and closing, it is easy to carry out the cleaning since the user can easily remove the dust attached to the tubular filter62.

Also, the dust collection case50of the electric vacuum cleaner according to the embodiment of the present invention is provided attachably and detachably to the vacuum cleaner main body20. According to this structure, it is easy to carry out the cleaning since the whole dust collection case50can be wet-cleaned.

Also, the electric vacuum cleaner according to the embodiment of the present invention, the intake opening33A of the motor fan33is provided to suck some of the air that flows into the tubular passage (air passage61) through the dust collection section (dust collection room section55) by communicating the dust collection section (the dust collection room section55) with the air guiding air passage (negative pressure room section56) and by communicating the dust collection section (dust collection room section55) with the intake opening33A of the motor fan33.

According to this structure, when the filter is clogged by the attachment of the dust to the filter (net filter F2), a flowing speed of the air to the dust collection section (dust collection room section55) becomes faster and the dust attached to the filter (net filter F2) is peeled off, therefore the clogging of the filter (net filter F2) can be solved.

Also, the electric vacuum cleaner according to the embodiment of the present invention, the ventilation opening59which exhausts some of the air guided from the dust strike section (strike section63) to the dust collection section (dust collection room section55) with the dust to the air guiding air passage (negative pressure room section56) by communicating the dust collection section (dust collection room section55) with the air guiding air passage (negative pressure room section56) is provided at a wall (top panel58) which forms and divides the dust collection section (dust collection room section55).

According to this structure, it is possible to contribute to a downsizing of the vacuum cleaner main body20since it is possible to guide the remaining air that flows into the dust collection section (dust collection room section55) to the intake opening33A of the motor fan33by utilizing the air guiding air passage (negative pressure room section56) which guides some of the air from the air guiding opening (openings64) provided at the tubular passage (passage61) directly to the intake opening33A of the motor fan33so as to maintain a direct-advancing element.

Also, the electric vacuum cleaner according to the embodiment of the present invention, the dimension of the ventilation opening59of the dust collection section (dust collection room section55) is smaller than the dimension of the air guiding opening (openings64) of the tubular passage (passage61). According to this structure, it is possible to increase the dust separation efficiency in the tubular passage (passage61) by increasing the amount of air which flows from the air guiding opening (openings64) of the tubular passage (passage61) directly to the intake opening33A of the motor fan33(i.e., maintaining a direct-advancing element) than the amount of air flowing to the dust collection section (dust collection room section55).

Also, the electric vacuum cleaner according to the embodiment of the present invention, the first filter (net filter F2) is attached to the air guiding opening (openings64) of the tubular passage (passage61). According to this structure, when the first filter (net filter F2) clogs, the wind amount of air that passes through the air guiding opening (openings64) reduces and the negative pressure at the air guiding air passage (negative pressure room section56) increases. When the negative pressure at the air guiding air passage (negative pressure room section56) increases, the negative pressure within the dust collection section (dust collection room section55) becomes larger through the ventilation opening59, and the wind velocity of air going straight of the tubular passage (passage61) becomes faster, so that a clogged situation of the first filter (net filter F2) can be avoided since the dust attached to the first filter (net filter F2) can be peeled off, therefore it is possible to avoid the deterioration in the sucking efficiency.

Also, the electric vacuum cleaner according to the embodiment of the present invention, the dust collection section (dust collection room section55) is provided at a down side position of the dust separation section60, the ventilation opening59is provided at an upper wall (top panel58) of the dust collection section (dust collection room section55), and the second filter (net filter F1) is attached to the ventilation opening59. According to this structure, as the ventilation opening59is provided in a vertical direction, it is possible to fall the dust attached to the second filter (net filter F1) by its own weight, therefore it is possible to remove the dust from the second filter (net filter F1) easily.

Also, the electric vacuum cleaner according to the embodiment of the present invention, the ventilation opening59is provided so that the air exhausted from the dust collection section (dust collection room section55) hits the first filter (net filter F2). According to this structure, it becomes easier to peel off the dust attached to the inner surface of the first filter (net filter F2).

INDUSTRIAL APPLICABILITY

As described above, in the dust separation structure of the electric vacuum cleaner relating the present invention, it is structured that the relatively heavy dust sucked with the air is adapted to go straight by using inertia force, and separate the air from the dust which is moving straight at a part where the dust is moving forward and suck by the motor fan. The dust separation structure as such can be utilized in ordinary household-use electric vacuum cleaner (including the ones which the power is supplied by a battery or a cord), an upright type electric vacuum cleaner or a commercial-use electric vacuum cleaner or the like.