U.S. patent number 3,653,189 [Application Number 05/004,328] was granted by the patent office on 1972-04-04 for vacuum cleaner.
This patent grant is currently assigned to Sanyo Electric Co., Ltd.. Invention is credited to Hideo Kashihara, Yuji Miyake, Ziyun Mizukawa, Kazuyoshi Takahashi, Takamitu Yamamoto.
United States Patent |
3,653,189 |
Miyake , et al. |
April 4, 1972 |
VACUUM CLEANER
Abstract
In a vacuum cleaner comprising a housing including a motor fan
unit and a dust collecting case detachably connected to the
housing, the dust collecting case is provided at its outlet opening
with a two-stage filtering means comprising a conical filter screen
of relatively large meshes and a cloth main filter which extend
toward the inside of the dust collecting case in such a spaced
relationship that the outlet opening is covered in double.
Inventors: |
Miyake; Yuji (Hyogo,
JA), Kashihara; Hideo (Hyogo, JA),
Takahashi; Kazuyoshi (Hyogo, JA), Yamamoto;
Takamitu (Hyogo, JA), Mizukawa; Ziyun (Hyogo,
JA) |
Assignee: |
Sanyo Electric Co., Ltd.
(Osaka, JA)
|
Family
ID: |
11572576 |
Appl.
No.: |
05/004,328 |
Filed: |
January 20, 1970 |
Foreign Application Priority Data
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Jan 20, 1969 [JA] |
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44/3995 |
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Current U.S.
Class: |
55/288; 15/323;
15/327.1; 15/412; 55/300; 55/305; 55/356; 55/367; 55/379; 55/429;
55/487; 55/529; 15/349; 55/DIG.3; 55/304; 55/319; 55/366; 55/372;
55/380; 55/433; 55/521 |
Current CPC
Class: |
A47L
9/20 (20130101); A47L 9/125 (20130101); Y10S
55/03 (20130101) |
Current International
Class: |
A47L
9/10 (20060101); B01d 041/02 () |
Field of
Search: |
;55/366-367,378-380,369,282-283,288-289,291-293,295,299-301,304-305,429,16.3
;15/327A-327E,327R,347,349,352 ;210/315 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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|
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|
|
22,333 |
|
Apr 1948 |
|
SF |
|
292,948 |
|
Jun 1928 |
|
GB |
|
561,214 |
|
Oct 1932 |
|
DD |
|
Primary Examiner: Talbert, Jr.; Dennis E.
Assistant Examiner: Gifford; Vincent H.
Claims
We claim:
1. A vacuum cleaner comprising a housing including a motor fan
unit, a dust collecting case detachably connected to said housing
and cooperating with said housing and said motor fan unit to form a
suction system, said dust collecting case being formed with an
inlet opening and an outlet opening, a filter unit, said filter
unit including pre-filtering means, main filtering means and a dust
removing device, said pre-filtering means including a generally
conically shaped screen having relatively large meshes which
extends into the inside of said dust collecting case, closure means
movable with respect to the apex of the screen for normally closing
the apex end of the screen, said main filtering means including a
cloth filter within said screen and disposed in a spaced
relationship therewith to form a fine dust particle collecting
space therebetween, means for detachably mounting said filter unit
to cover said outlet opening and to have air with dust and dirt
particles entrained therein impinge upon said filter unit, and said
dust removing device comprising manually operable means for aiding
in the removal of dust from said main filtering means, said
manually operable means being in contact with said main filtering
means and being manually operable when the dust collecting case is
detached from said housing and said pre-filtering and main
filtering means are still part of said filter unit.
2. A vacuum cleaner according to claim 1, wherein said cloth filter
has an apex portion which is concentrically waved and said dust
removing device is a vibrator mounted as part of said filter unit
to contact said apex portion of said cloth filter.
3. A vacuum cleaner according to claim 1, further comprising a
support frame located within said filter screen for maintaining
said cloth filter in substantially conical form, said cloth filter
being attached to said support frame and said frame being removable
from within said filter screen with the cloth filter attached
thereto to serve as said means for aiding in the removal of dust
from said cloth filter.
4. A vacuum cleaner according to claim 3 wherein said closure means
for closing the opening at the apex end of said filter screen
comprises a detachable plug to which said frame and said cloth
filter means are also attached, removal of the plug permitting the
frame and cloth filter to be withdrawn from within the filter
screen so that the dust can be removed from said cloth filter and
pass into the dust case through the open apex end of the filter
which is detachably mounted to screen.
5. A vacuum cleaner as in claim 4 further comprising means for
detachably mounting the filter unit to the dust collecting
case.
6. A vacuum cleaner according to claim 4 further comprising a
handle rod attached to said plug to facilitate removal of the cloth
filter which is detacably mounted to said filter screen apex said
filter screen.
7. A vacuum cleaner as in claim 1 wherein said closure means for
closing the apex end of the filter screen comprises a plug which is
detachably mounted to said filter screen apex end and to which a
portion of the cloth filter is also attached, said plug being
removed to open the apex end of the filter screen when said means
for aiding in the removal of dust from said cloth filter is
operated.
8. A vacuum cleaner as in claim 7 further comprising a handle rod
attached to said plug to facilitate the removal of the cloth filter
from within said filter screen.
9. A vacuum cleaner according to claim 1 wherein the wall of said
dust collecting case is formed with said closure means closing the
open apex end of said filter screen, said closure means located on
the wall of said dust collecting case facing said outlet opening so
that said apex opening of said filter screen is closed when said
filter unit is mounted over said outlet opening of said dust
collecting case.
10. A vacuum cleaner according to claim 9, further comprising a
support frame located within said filter screen for maintaining
said cloth filter in substantially conical form, said cloth filter
being attached to said support frame and said frame being removable
from within said filter screen with the cloth filter attached
thereto to serve as said means for aiding in the removal of dust
from said cloth filter.
Description
BACKGROUND OF THE INVENTION
This invention relates to new and improved vacuum cleaner and more
particularly to improvements in detachable dust collecting cases
for vacuum cleaners.
In conventional vacuum cleaners a cloth bag is employed for
filtering air through the cleaner body. Prior to cleaning operation
another disposable filter bag made generally of a piece of paper is
inserted within the fixed cloth bag which together forms a
filtering system. Upon operation of the cleaner, the insucked air
passes through the filtering system and almost all of the dust
carried with the air stream is collected primarily by the paper
bag. As this dust collection proceeds, an incalculable number of
fine dust particles stick to the entire inner surface of the paper
bag resulting in the clogging of fine filtering apertures in the
bag with dust particles. This premature clogging of the paper bag
tends to obstruct the free passage of insucked air flow through the
cleaner and greatly reduces air suction by the cleaner only minutes
after it has been put into operation. As is apparent to those
skilled in the art, this reduction of air sucking capability of the
cleaner causes, in turn, the reduction of its dust collecting
ability. Therefore, in order to maintain the desired dust
collecting capability it becomes necessary to change the paper bag
with a fresh one well before the old one is substantially filled
with the assembled dust. However, frequent replacement of the paper
bags is troublesome as well as costly. As a paper bag is fragile in
nature, some limitations are placed on the maximum dimensions of
the bag, which in turn restricts the maximum space within the bag
available for the storage of collected dust and dirt. This also
necessitates frequent change of dust bags since such bags can
accommodate only a small amount of dust removed from the air stream
through the cleaner.
Another important disadvantage with the conventional vacuum
cleaners is the difficulty encountered in disposing of the dust
collected during operation. It is therefore highly desirable to
provide a vacuum cleaner which completely eliminates the above
noted shortcomings.
In order to avoid the above mentioned disadvantages, an attempt has
been made to utilize a two-stage filtering system and a detachable
dust collecting case. The known two-stage filtering system
comprises a first dust collecting receptacle having incorporated
therein a filtering screen of a relatively large mesh size and
detachably positioned within the cleaner body. The known filtering
system further includes a second filtering member of fine mesh size
located immediately down-stream of the first dust collecting case
within the cleaner body with its inlet opening communicating with
the outlet opening of the first dust collecting receptacle. With
this arrangement, insucked air through the cleaner body passes
initially through the first receptacle where dust having a
relatively large size is filtered from the air stream by the
filtering screen and through the second filtering member where fine
dust particles are removed from the air flow. Vacuum cleaners of
this type are disclosed in the co-pending U.S. Pat. application,
Ser. No. 806,974, entitled "Vacuum Cleaner" filed Mar. 13, 1969,
which is assigned to the assignee of the subject application.
The above mentioned two-stage filtering system is however
disadvantageous in that it necessitates the provision of a utility
chamber for the second filtering member within the cleaner body at
a position immediately down-stream of the first dust collecting
receptacle. In addition, it is not so easy to remove the collected
fine dust particles from the second filtering member which is
located in an elongated chamber within the cleaner body.
A primary object of the invention is to provide a new and improved
vacuum cleaner in which a two-stage filtering system is entirely
enclosed in a detachable dust collecting case in a highly compact
manner but without sacrificing dust collecting efficiency.
Another object of the invention is to provide a new and improved
vacuum cleaner which greatly facilitates the disposal of all the
collected dust and dirt.
A further object of the invention is to provide a new and improved
vacuum cleaner in which the desired dust collecting capability
thereof is always maintained through its operation.
A still further object of the invention is to provide a new and
improved vacuum cleaner in which a detachable dust collecting case
further includes a dust removing device therein.
One of the other objects is to provide a new and improved vacuum
cleaner in which fine dust particles collected at the second stage
can be located in the detachable dust collecting case with
collected dust particles having relatively large sizes for
facilitating the disposal of them.
SUMMARY OF THE INVENTION
The vacuum cleaner according to the invention comprises a housing
including a motor fan unit and a dust collecting case detachably
connected to said housing and cooperating with the housing to form
a suction system. The dust collecting case is provided with an
inlet opening and an outlet opening. According to the invention the
outlet opening of the dust collecting case is successively covered
by pre-filtering means and main filtering mean. The prefiltering
means comprises a substantially conically shaped screen of
relatively large mesh which extends into the inside of the dust
collecting case. The main filtering means comprises a cloth filter
which extends into the inside of the conically shaped screen and is
disposed in a spaced defined with said conically shaped screen so
as to form a fine dust particle collecting space therebetween.
With the above arrangement, the filter screen as a first filtering
member can entirely be contained within the dust collecting case
since it extends into the inside of the dust collecting case. The
conical form of the filter screen is advantageous for increasing
the effective filtering area and facilitates forming a space for
accommodating the second filtering means therein. With the
arrangement of the main filter within the space define by the
conical filter screen, the two-stage filtering system can entirely
be accommodated in the dust collecting case.
In order to prevent the dust collected in the case to escape
therefrom, the inlet opening may be provided with a check
valve.
In a preferred embodiment of the invention, the position of the
inlet opening of the dust collecting case is offset from the
central axis of the conically shaped screen so as to direct the air
flow through the inlet opening onto a top surface of the conically
shaped screen, whereby the top surface of the screen may always be
kept free from clogging. This feature is important to maintain the
cleaner in a good dust collecting condition.
The effective filtering area may be increased by shaping it in a
truncated cone form having an apex portion which is concentrically
waved.
It is preferred to provide the cloth filter with a dust removing
device. The dust removing device may be a manually operative
vibrator attached to the cloth filter.
In another embodiment of the invention, the conically shaped screen
can be provided at its apex portion with an opening which is closed
by a detachable plug. The plug may be mounted on the top end of the
cloth filter and have a handle rod attached thereto. The opening at
the apex portion of the conical screen may alternatively be closed
by the end wall of the dust collecting case.
In order to hold the cloth filter in a conical form, a support
frame may be used.
It is possible to locate the inlet opening of the dust collecting
case at the same side as that where the outlet opening thereof is
located. In such the case like this, the air flow is re-directed by
substantially 180.degree., or U-turned, in the dust collecting
case.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be fully understood from the following
description taken in connection with the accompanying drawings in
which:
FIG. 1 is a sectional view of a vacuum cleaner embodying the
present invention;
FIG. 2 is a sectional view of the dust collecting case illustrated
in FIG. 1, showing the state in which it is detached from the
cleaner housing and placed for disposing of the collected dust;
FIG. 3 is a sectional view similar to FIG. 1 of another embodiment
of the invention;
FIG. 4 is a sectional view similar to FIG. 3 of the dust collecting
case illustrated in FIG. 3;
FIG. 5 is a sectional view similar to FIG. 1 of a further
embodiment of the invention;
FIG. 6 is a sectional view similar to FIG. 2 of the dust collecting
case illustrated in FIG. 5;
FIg. 7 is a sectional view similar to FIG. 1 of a still further
embodiment of the invention; and
FIG. 8 is a sectional view similar to FIG. 2 of the dust collecting
case illustrated in FIG. 7.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings and particularly to FIG. 1, there is
shown a vacuum cleaner having a detachable dust collecting case
embodying the present invention. The vacuum cleaner is illustrated
as having a cleaner housing generally indicated by the reference
numeral 20. The cleaner housing 20 may preferably be of a
horizontally elongated hollow cylindrical configuration.
The cleaner housing 20 is integrally provided at its front end with
an inlet fitting 21 adapted to be connected to a suction tubular
hose (not shown) of well-known construction. The cleaner housing 20
is formed at the position immediately behind the inlet fitting 21
with an open space or cavity 22 for accommodating a dust collecting
case 23. The rear end of the cavity 22 is defined by a partition
wall 24 which is integrally formed with the cleaner housing 20 and
extends vertically. The top of the cavity 22 is open so that the
dust collecting case 23 may be put in and removed from the cavity
22 though its top opening. The dust collecting case 23 comprises a
box like case or receptacle open at one end and closed at the other
end. More specifically, the dust collecting case 23 is formed as an
independent unit having such a substantially cylindrical
configuration that when positioned in place within the cavity 22 it
fits perfectly thereinto to form an integral part of cleaner
housing 20. The dust collecting case 23 is provided at its top with
clamping or locking means 25 having a spring operated latch 26
which is engageable with a cooperating opening 27 formed in the
partition wall 24.
The dust collecting case 23 made as a separate, detachable unit
includes a pre-filtering means 28. The pre-filtering means is
detachably mounted to the opening 27 at the rear end of the dust
collecting case 23 so as to cover the opening 29. The pre-filtering
means comprises a substantially conically shaped rigid screen 30
having a peripheral flange 31 which is engaged with a step 32
formed at the inner periphery of the opening 29. The filter screen
30 may be made of plastic materials, fine metal wires or the like
and have a relatively large mesh size.
With the above arrangement, the conical filter screen 30 extends
into the case 23 with its front end towards wall 33 while the
peripheral flange 31 is supported by step 32 of the inner periphery
of the opening 29 at the rear end of the case.
Within the conical filter screen 30 main filtering means 40 is
accommodated. Main filtering means comprise a filter cloth 41
shaped in a truncated cone form having a concentrically waved apex
portion 42 and a peripheral bottom flange 43. The filter cloth 41
is spaced from the filter screen 30 so that dust may be collected
therebetween. The peripheral bottom flange 43 may be made of a
packing material so that it may be supported in a sealing
arrangement on the peripheral flange 31 of the conical filter
screen 30.
Further within the main filter 40 a dust removing device or
vibrator 50 is accommodated. The vibrator 50 may comprise a support
frame 51, a driven shaft 52 supported by the support frame 51, a
vibrating plate 53 and cam means 57 associated with the driven
shaft 52 for actuating the vibrating plate 53. The support frame 51
comprises a bearing portion 51a for carrying the driven shaft 52, a
cylindrical portion 51b for carrying the boss portion 54 integrally
formed with the vibrating plate 53, a peripheral flange 51c and
radial leg portions 51d for connecting the bearing portion 51a and
the cylindrical portion 51b to the peripheral flange 51c. The
peripheral flange 51c is sealingly supported by the peripheral
bottom flange 43 at a circular groove 55 formed therein. The driven
shaft 52 is provided at its one end with a handle 56 and at its
other end with a cam 57 member having a spiral cam surface 57a
which is engaged with a cooperating spiral cam surface 58 formed at
the boss portion 54 of the vibrating plate 53. The vibrating plate
53 is in contact with the apex portion 42 of the main filter 40.
The reference numeral 59 indicates a spring inserted between the
support frame 51 and the vibrating plate. The vibrating plate 53 is
axially movable against the force of the spring 59 with the boss
portion 54 sliding within the cylindrical portion 51b of the
support frame 51.
The bottom wall 33 of the dust collecting case 23 is provided with
an opening 61 which is placed in alignment with the inlet fitting
21 of the housing 20 when the dust collecting case is placed in the
housing 20. The position of the opening 61 is located upwardly from
the central axis of the conical filter screen 30. The reference
numeral 62 indicates a check valve attached to the opening 61 so
that air can only enter into the case 23 through the opening
61.
An air discharge chamber 70 is formed within the housing 20 between
the before mentioned partition wall 24 and another partition wall
71. The partition wall 24 is formed with a large opening 72
confronting the opening 29 at the rear end of the dust collecting
case 13. Within the air discharge chamber 70 there is resiliently
supported a motor fan unit 73 of conventional construction for
causing air to flow rapidly through the cleaner with its suction
side confronting the opening 72 of the partition wall 24. The
reference numerals 74 and 75 indicate elastic material seats
attached to the partition walls 24 and 71, respectively, for
supporting the motor fan unit therebetween. The elastic material
seat 74 is formed with an extension 76 with which the flange 51c of
the support frame 51 of the vibrator 50 can become in contact in a
sealing engagement when the dust collecting case 23 is placed in
the housing 20. The reference numeral 77 indicates a discharge port
through which the filtered air is discharged to the outside.
Another space or chamber 80 is formed within the housing 20 between
the partition wall 71 and a rear end cover 81 for containing a reel
82 for winding up a predetermined length of electric cord 83 which
supplies electric power to the motor fan unit 73 of the cleaner
from a suitable AC power supply line.
In FIG. 1, the reference numeral 85 indicates a handle for carrying
the cleaner housing and the reference numeral 86 indicates wheels
for rolling the cleaner housing.
The operation of the vacuum cleaner constructed as above in
accordance with the present invention is next explained in detail.
With the dust collecting case 23 fitted and locked in place within
the housing 20 and a suction tubular hose (not shown) connected to
the inlet fitting 21 by inserting it into the fitting, the motor
fan unit 73 is energized to initiate suction of air into the
cleaner for effecting vacuum cleaning. During operation of the
motor fan unit 73, air carrying dirt and dust away from the surface
to be cleaned rushes through the inlet fitting 21 and the opening
61 into the dust collecting case 23. This air flow through the
opening 61 passes through conical filter screen 30 and then through
the cloth filter 41. Air then flows through the opening 72 into the
discharge chamber 70 to be discharged to the outside through the
discharge port. During this passage dust and dirt of relatively
large mass or size, such as rugs or torn pieces of cloth and paper
and the like, carried by the air stream into the cleaner are
filtered from the air by the conical screen 30 having relatively
large filtering meshes. This dust of large size filtered or trapped
by the conical screen 30 accumulates under the cone 30 in layer
upon layer until the space defined by the conical screen 30 and the
dust collecting case 23 is completely filled up. As the trapped
dust and dirt gathers on the conical screen 30 it is compacted by
the high pressure jet of air and following dust mass impinging
thereon. Thus, an efficient use of the available space within the
dust collecting case 23 become possible i.e., a relatively large
amount of dust can be packed in the predetermined space of the dust
collecting case. Further, as the pieces or particles of larger size
are piled and compressed tightly on the screen 30 in layers along a
bottom generation line of the cone, this compacted body of dirt
serves as an additional filtering medium which remove comparatively
smaller size dust particles including fine particles from the air
stream entering the chamber 39. If the dust covers the entire area
of the screen 30 and the thickness of the dust layer becomes
sufficiently great, the flow resistance will be greatly increased
and filtering efficiency will be inevitably lowered before the
space 39 becomes fully occupied with dust and dirt. According to
the invention, however, the screen 30 is formed in a conical shape
so that the effective filtering area is greatly enlarged. In
addition, the inlet opening 61 is displaced upwardly from the
extension of the central axis of the conical screen so as to direct
the air flow through the opening 61 onto the top surface of the
cone 30, thereby to blow in the direction of a top generation line
of the cone 30 and keep that area free of any dust accumulation
even when the remaining filtering surface of the cone becomes
encircled by a progressively piled up body of dust. Therefore, it
will be apparent that the upper surface of the cone 30 remains as
the only area free of dirt accumulation until substantially all of
the available space in the chamber 39 is filled with the collected
dust, which maintains good filtering effect of the screen 30 until
such time.
The air then passes through the main filter 41 made of cloth. At
this stage, substantially all of the fine dust particles which were
not trapped by the conical screen 30 of large meshes are filtered
by the main filter 41 from the entering air before it moves through
the motor fan unit 73. Only dust free air is exhausted by the motor
fan unit 73 through the chamber 70 and through the discharge port
77 out of the cleaner housing 20.
According to the invention, the main filter 41 is formed in a
truncated cone having an apex portion 42 which is concentrically
waved so that the effective filtering surface is enlarged to the
utmost extent, thereby to increase the filtering capacity.
Thus, with the improved vacuum cleaner of the invention, a two step
dust filtering or collection from the insucked air through the
cleaner is effected which assures efficient as well as high speed
and large volume of dust entrapment. In actual practice, almost all
of the dust and dirt, including fine particles, sucked into the
cleaner is initially retained by the conical screen 30 which forms
the first filtering stage and a comparatively small amount of fine
dust particles pass through the cone 30 to be filtered by the cloth
filter 41 which constitutes the second filtering stage.
For disposing of the dust body and fine particles collected in the
spaces 39 and 38, respectively, the dust collecting case 23 is
detached from the cleaner housing 20 by releasing the locking
element 25 from its cooperating member 26. The detached case 23 is
put in an upright position with the bottom wall 33 resting on the
floor as shown in FIG. 2. The vibrator 50 is then operated by
rotating the shaft 52. The rotation of the shaft 52 causes the
vibrating plate 53 to be vibrated in axial directions along shaft
52 due to the cooperating action between the two cam elements 57a
and 58. The vibration of the vibrating plate is in turn transmitted
to the cloth filter 41 at its apex portion 42, whereby the dust
particles which have been attached to the cloth filter 41 are
shaken off. Thereafter, the main filtering means 40 with the
vibrator 50 is removed from the pre-filtering means 28 and the
pre-filtering means 28 is removed from the case 23 so that the
respective dust layers collected in the chamber 38 and 39 may be
disposed of.
It will be appreciated that prefiltering means, main filtering
means and the dust removing device are accommodated within a
detachable dust collecting case in an extremely compact form and in
such a manner that the dust collecting and disposing operation can
be carried out efficiently and speedily.
FIGS. 3 and 4 illustrate another embodiment of the invention in
which the dust collecting case is mounted at the front end of the
cleaner housing. Referring to FIG. 3, the vacuum cleaner
illustrated therein comprises a housing 120 containing a motor fan
unit 173 and a dust collecting case 123 which is mounted at the
front end of the housing 120.
The dust collecting case 123 may preferably be of a hollow
cylindrical, or square or polygonal configuration extending in a
horizontal direction. The dust collecting case 123 is provided at
its opposite ends, namely, at its front and rear ends, with a
relatively small inlet opening 161 and a large outlet opening 129.
The inlet opening 161 is adapted to be connected to a tubular
suction hose (not shown) of well known construction and is provided
with a check valve 162. The outlet opening 129 is covered by a
filter assembly generally indicated by the reference numeral 128.
The filter assembly comprises a substantially conically shaped
filter screen 130 and a cloth filter 141. The conically shaped
filter screen 130 is a pre-filter and the cloth filter is a second
and main filter. The filter screen 130 may preferably be made of a
plastic material and provided with a number of apertures 135 having
a relatively large diameter. The filter screen 130 is supported at
its peripheral bottom flange 131 by a peripheral packing 137
attached to the inner periphery of the opening 129 and extends
inwardly of the case 123. The filter screen 130 is provided at its
top end with an opening 136. The top end opening 136 of the filter
screen 130 is closed by a plug 134 which is fixed to the top end of
the cloth filter 141. The cloth filter 141 extends within and along
the conically shaped screen 130 but it is so spaced from the screen
130 that a space 138 is formed therebetween. The bottom end of the
cloth filter 141, which also is of a substantially conical shape,
is fixed to the peripheral packing 137. In order to keep the cloth
filter in a spaced relationship from the filter screen 130, a
support frame 151 is connected to a handle rod 152 for the plug 134
at the top end of the cloth filter 141.
As mentioned before, the dust collecting case 123 is detachably
connected to the front end of the housing 120 containing a motor
fan unit 173. The housing 120 is provided at its front end with an
opening 172 which confronts the outlet opening 129 when the dust
collecting case 123 is connected to the housing 120 as shown in
FIG. 3. The reference numeral 176 indicates a support on which the
bottom end of the handle rod 152 rests when the case 123 is
connected to the housing 120. The housing 120 defines a discharge
chamber 170 and is provided with a discharge port (not shown)
through which the filtered air is exhausted to the outside. In FIG.
3 the reference numeral 185 indicates a handle for carrying the
housing 120 and the reference numeral 186 indicates wheels for
rolling the dust collecting case 123 and the housing 120 when those
are connected to each other as shown in FIG. 3.
The operation of the vacuum cleaner illustrated in FIG. 3 is
similar to that illustrated in FIG. 1. With the dust collecting
case 123 being connected to the housing 120 and a tubular hose (not
shown) being connected to the inlet fitting 161 of the dust
collecting chamber, the motor fan unit 173 is energized to initiate
suction of air into the cleaner for effecting vacuum cleaning.
During operation of the motor fan unit 173, air carrying dirt and
dust away from the surface to be cleaned passes through the inlet
fitting 161 into the dust collecting chamber 139 which is defined
by the case 123 and the conically shaped filter screen 130. This
air flow passes successively through the conically shaped filter
screen 130 of relatively large mesh and the finer mesh cloth filter
141. The filtered air then flows through the opening 172 into the
discharge chamber 170. During this passage dust and dirt of
relatively large mass or size, such as rugs or torn pieces of cloth
and paper and the like, carried by the air stream into the cleaner
are filtered from the air by the filter screen 130 having
relatively large filtering meshes before it enters into the space
138. This dust and dirt of larger size pieces filtered or trapped
by the screen 130 accumulates in successive layers. As the trapped
dust mass gathers on the screen, it is compacted by the high
pressure jet of air and following dust mass impinging thereon. As
the dust of larger size is piled and compressed tightly on the
screen 130 in layers, this compacted body of dirt serves as an
additional filtering medium which remove comparatively smaller
sizes of dust particles, including fine particles, from the air
stream through the chamber 139.
The air then passes through the main filter 141 made of cloth. At
this stage, almost all of the fine dust particles which could not
be trapped by the conical screen 130 of large meshes are filtered
by the main filter 141 from air before it moves though the motor
fan unit 173. Only dust free air is exhausted by the motor fan unit
173 through the chamber 170 and through the discharge port (not
shown) out of the cleaner housing 120.
For disposing of the compacted dust body and fine particles
collected in the spaces 139 and 138, respectively, the dust
collecting case 123 is detached from the housing 120. The detached
case 123 is put in an upright position with the bottom wall 133
resting on the floor as shown in FIG. 4. The handle rod 152 with
the support frame 151 is then pulled upwardly with the plug 134
being removed from the opening 136 thus gravitating dust from
filter 141 into chamber 139.
The embodiment illustrated in FIGS. 3 and 4 is advantageous in that
fine dust particles can also be collected in the chamber 139 as
well as dust particles and other pieces of material having
relatively large sizes. In this embodiment it is not necessary to
remove the main filter 141 from the pre-filter 130, as in the
embodiment of FIGS. 1-2.
A further embodiment of the invention is illustrated in FIGS. 5 and
6. Refering to FIG. 5 the vacuum cleaner illustrated therein
comprises a housing 220 containing a motor fan unit 273 and a dust
collecting case 223 which is mounted at the front end of the
housing 220.
The dust collecting case 223 may preferably be of a hollow
cylindrical, or square, or polygonal configuration extending in a
horizontal direction. The dust collecting case 223 is provided at
its opposite ends, namely, at its front and rear ends, with a
relatively small inlet opening 261 and a large outlet opening 229.
The inlet opening 261 is adapted to be connected to a suction
tubular hose (not shown) of conventional construction and is
provided with a check valve 262. The outlet opening 229 is covered
by a filter screen 230. The filter screen 230 may preferably be
made of a plastic material and provided with a number of apertures
235 having a relatively large diameter to form a screen having
relatively large meshes. The filter screen 230 is substantially
conically shaped and is supported at its peripheral bottom flange
231 by a step 232 formed at the inner periphery of the opening 229
of the case. The conically shaped filter screen 230 is provided at
its apex portion with an opening 236 which is engaged with and
closed by the front wall 233 of the case 223 as shown in FIG. 5. A
dust collecting chamber 239 is thus defined by the case 223 and the
filter screen 230. Within the conically shaped filter screen 230 a
cloth filter 241 is placed in a spaced relationship with respect to
the filter screen 230 so as to form a fine dust particle collecting
chamber 238 therebetween. The cloth filter 241 is maintained in a
substantially conical form by a support frame 251. The bottom hem
of the cloth filter 241 is fixed to the peripheral flange 231 of
the filter screen 230 by means of a ring-shaped packing 237. The
free top end of the cloth filter is connected to the top of the
conical frame 251, the bottom flange 252 is supported at the
packing 237.
The dust collecting case 223 is detachably connected to the front
end of the housing 220 containing a motor fan unit 273. The housing
220 is provided at its front end with an opening 272 which
confronts the outlet opening 229 when the dust collecting case 223
is connected to the housing 220 as shown in FIG. 5. The housing 220
defines a discharge chamber 270 and is provided with a discharge
port (not shown) through which the filtered air is exhausted to the
outside. In FIG. 5 the reference numeral 285 indicates a handle for
carrying the housing 220 and the reference numeral 286 indicates
wheels for rolling the dust collecting case 223 and the housing 220
when those are connected to each other as shown in FIG. 5.
The operation of the vacuum cleaner illustrated in FIG. 5 is
similar to those illustrated in FIGS. 1 and 3. The conically shaped
filter screen 230 and the conical cloth filter 241 function as a
prefilter and a main filter as in the previously disclosed
embodiments of FIGS. 1 and 3.
For disposing of the dust body and fine particles collected in the
spaces 239 and 238, respectively, the dust collecting case 223 is
detached from the housing 220. The detached case 223 is put in an
upright position with the bottom wall 233 resting on the floor as
shown in FIG. 6. The filter screen 230 is then upwardly moved so as
to release the end of screen 230 defining opening 236 from the
bottom wall 233 of the case 220. The support frame 251 with the
cloth filter 241 is pulled upwardly as shown in FIG. 6 and shaken
to remove the dust particles so that they fall down through the
opening 236 to the chamber 239.
FIGS. 7 and 8 illustrate still another embodiment of the invention.
Referring to FIG. 7 the vacuum cleaner is illustrated as having a
cleaner housing generally indicated by the reference numeral 320.
The cleaner housing 320 may preferably be of a horizontally
elongated hollow cylindrical configuration.
The cleaner housing 320 is integrally provided at its front top
with a longitudinally extending inlet fitting 321 adapted to be
connected to a tubular suction hose (not shown) of conventional
construction. The housing 320 defines beneath the inlet fitting 321
a discharge chamber 370 containing a motor fan unit 373. The
cleaner housing 320 is formed at the position immediately behind
the inlet fitting 321 and the discharge chamber 370 with an open
space or cavity 322 for accommodating a dust collecting case 323.
The rear end of the cavity 322 is defined by an upright partition
wall 324 which is integrally formed with the cleaner housing 320.
The top of the cavity 322 is open so that the dust collecting case
323 may be put in and removed from the cavity through its top
opening.
The dust collecting case 323 comprises a box like case or
receptable open at one end and closed at the other end. More
specifically, the dust collecting case 323 is formed as an
independent unit having such a substantially cylindrical
configuration that when positioned in place within the cavity 322
it fits perfectly thereinto to form an integral part of the cleaner
housing 320. The dust collecting case 323 is provided at its top
with locking means 325 having a spring operated latch 326 which is
engageable with a cooperating opening 327 formed in the housing
320.
The dust collecting case 323 made as a separate, detachable unit
includes a pre-filtering means 328. The pre-filtering means
comprises a substantially conically shaped screen 330 which extends
from the open front end of the case 323 to the closed rear end of
the case 323 to partition the inside of the case 323 into two
chambers 339 and 338. The conically shaped filter screen 330 has
openings 329 and 336 at its opposite ends, namely, at the front and
rear ends, respectively. The filter screen 330 is provided at its
front end with a peripheral flange 331 which is engaged with an
inner peripheral packing 332 attached to the inner periphery of the
front opening 329 of the case 323. The rear end opening 336 of the
filter screen 330 is closed by the rear end wall 333 of the case
323. The filter screen 330 may be made of plastic materials, fine
metal wires or the like and have a relatively large mesh size.
Within the conical filter screen 330 main filtering means 340 is
accommodated. Main filtering means comprises a filter cloth 341
shaped as a truncated cone having a concentrically waved apex
portion 342 and a peripheral bottom edge portion 343 which is fixed
to the peripheral packing 332. The filter cloth 341 is spaced from
the filter screen 330 so that dust may be collected
therebetween.
Further within the main filter 340 a dust removing device or
vibrator 350 is accommodated. The vibrator illustrated in FIG. 7 is
substantially the same as that illustrated in FIG. 1. No further
explanation is, therefore, necessary for the vibrator 350.
The peripheral flange 331 of the filter screen 330 has an extension
331a having an opening 361 which is in alignment with the inlet
fitting 321 so that the air carrying dirt and dust may flow through
the opening 361 into the chamber 339. The reference numeral 363
indicates a guide channel for directing the air flow toward the top
surface of the conical filter screen 330. In FIG. 7 the reference
numeral 377 indicates the discharge port for the cleaner which is
in the form of slits, the reference numeral 385 indicates a handle
for carrying the housing 320, the reference numeral 386 indicates
wheels for rolling the housing 320 and the reference numeral 382
indicates a reel for winding up an electrical cord for supplying
electric power to the motor fan unit 373.
The operation of the vacuum cleaner illustrated in FIG. 7 is
substantially the same as any of the vacuum cleaners illustrated in
FIGS. 1, 3, and 5 except that the air flow is re-directed by
substantially 180.degree. (U-turned) in the case 323. This
embodiment can dispense with the provision of a check valve at the
inlet opening 361 because the rear end wall 333 of the dust
collector housing 222 is completely closed.
For disposing of the dust body and fine particles collected in the
spaces 339 and 338, respectively, the dust collecting case 323 is
detached from the cleaner housing 320 by releasing the lock element
326 from its cooperating member 327. The detached case 323 is put
in an upright position with the bottom wall 333 resting on the
floor as shown in FIG. 8. The vibrator 350 is then operated to
vibrate the cloth filter 341 whereby the dust particles which have
been attached to the cloth filter 341 are removed and fall down
toward the bottom of the case 323. The combination of the filtering
means 328 and 340 with the dust removing device 350 is then removed
from the dust collecting case so that the dust collected in the
case may in turn be emptied from the case.
* * * * *