U.S. patent application number 09/847808 was filed with the patent office on 2001-12-06 for vacuum collection bag and method of operation.
Invention is credited to Scanlon, John J..
Application Number | 20010047721 09/847808 |
Document ID | / |
Family ID | 26896982 |
Filed Date | 2001-12-06 |
United States Patent
Application |
20010047721 |
Kind Code |
A1 |
Scanlon, John J. |
December 6, 2001 |
Vacuum collection bag and method of operation
Abstract
The present invention is an improved vacuum collection bag for
vacuum cleaners and other appliances. By employing an impermeable
bag and an air-permeable particle separator together with a tight
seal against a vacuum system dirt tube in place of a conventional
paper bag filter, it has been determined that the vacuum cleaner
bag can be reused and significantly improve the filtration
performance of the vacuum system.
Inventors: |
Scanlon, John J.;
(Wilmington, DE) |
Correspondence
Address: |
John J. Scanlon
1308 Hillside Boulevard
Wilmington
DE
19803
US
|
Family ID: |
26896982 |
Appl. No.: |
09/847808 |
Filed: |
May 2, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60201654 |
May 3, 2000 |
|
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Current U.S.
Class: |
95/273 ; 55/364;
55/369 |
Current CPC
Class: |
B01D 46/521 20130101;
B32B 27/08 20130101; A47L 9/14 20130101; B01D 39/2017 20130101;
B01D 39/1692 20130101; B01D 39/1623 20130101; B01D 46/10 20130101;
Y10S 55/03 20130101; B01D 2279/55 20130101; Y10S 55/02 20130101;
B32B 27/10 20130101; B01D 46/48 20130101; B01D 39/18 20130101; A47L
9/149 20130101 |
Class at
Publication: |
95/273 ; 55/364;
55/369 |
International
Class: |
B01D 046/00 |
Claims
What is claimed is:
1. A vacuum cleaner bag comprising: an impermeable media forming a
cavity for storing a dirt; an inlet for attachment of said bag to a
dirt tube and for conveying said dirt into said cavity; and an
integrally connected air-permeable particle separator means sealed
over an exit hole in said impermeable media for retaining said dirt
in said cavity as a clean air exits said bag.
2. The bag of claim 1 further comprising a re-sealable bag open-end
for removing said dirt and reusing bag.
3. The re-sealable bag open-end of claim 2 wherein said bag open
end consists of folded impermeable media secured in position.
4. The re-sealable bag open-end of claim 2 wherein said bag open
end consists of interlocking parts for closing and opening end of
bag consisting of said impermeable media.
5. The air-permeable particle separator means of claim 1 wherein
air-permeable particle separator means is air-permeable material
capable of separating dirt from airflow.
6. The air-permeable particle separator means of claim 1 wherein
air-permeable particle separator means is a frame sealed to said
exit hole of said impermeable media and a pleated media is sealed
in said frame.
7. The air-permeable particle separator means of claim 1 wherein at
least one layer is expanded polytetrafluoroethylene (PTFE)
membrane.
8. The air-permeable particle separator means of claim 1 wherein at
least one layer is microfiberglass.
9. The air-permeable particle separator means of claim 1 wherein at
least one layer is paper.
10. The air-permeable particle separator means of claim 1 wherein
at least one layer is non-woven.
11. The air-permeable particle separator means of claim 1 wherein
the filtration efficiency is equal to or greater than HEPA.
12. The impermeable media of claim 1 wherein said impermeable media
is transparent for observing contents of bag.
13. The air-permeable particle separator means of claim 1 wherein
air-permeable particle separator means consists of flat media.
14. The bag of claim 1 further comprising antimicrobial
materials.
15. The bag of claim I further comprising odor removing means.
16. The bag of claim 1 further comprising scenting means.
17. The air-permeable particle separator means of claim 1 wherein
said air-permeable particle separator means is so that said inlet
does not align airflow directly into media.
18. The air-permeable separator means of claim 1 further comprising
a pre-filter to keep large dirt from entering separator means.
19. The method of collecting a dirt in a vacuum cleaner wherein: An
inlet of a bag comprising impermeable media and an air-permeable
particle separator is installed in a vacuum cleaner in an
essentially leak-proof manner over a dirt tube; Dirt is conveyed
into bag cavity; Air-permeable particle separator separates dirt
from air; and Cleaned air exits said bag through said air-permeable
particle separator and said dirt is retained in said bag
cavity.
20. The method of collecting a dirt in a vacuum cleaner bags
emptying its contents and reusing said bag wherein: An inlet of a
bag comprising impermeable media and an air-permeable particle
separator is installed in a vacuum cleaner in an essentially
leak-proof manner over a dirt tube; Dirt is conveyed into bag
cavity; Air-permeable particle separator separates said dirt from
air; Cleaned air exits said bag through said air-permeable particle
separator and said dirt is retained in said bag cavity; Bag is
removed from vacuum cleaner; Bag is opened and dirt is removed; Bag
is re-closed; and Bag is re-installed in vacuum cleaner for re-use.
Description
BACKGROUND OF INVENTION
[0001] 1. Field of Invention
[0002] The present invention relates to collection bags in
appliances, such as a vacuum cleaner.
[0003] 2. Description of Related Art
[0004] A variety of vacuum cleaners are presently available that
collect dirt in a disposable paper bag filter. These vacuum
cleaners are found in several forms including upright, canister,
and wet/dry vac configurations. These device are sold under the
brand names Hoover, Eureka, Royal Dirt Devil, Panasonic, Sears
Kenmore, SHOP-VAC, etc.
[0005] The majority of vacuum cleaners purchased today utilize a
porous paper bag to filter and store dust collected by a vacuum
cleaner. As air pneumatically conveys dirt into the bag, it exits
through the porous paper media surrounding the cavity leaving the
large dirt in the bag. Because of the relatively poor filtration
efficiency of paper filter media, better vacuum cleaners employ
multi-stage filtration systems that generally employ a HEPA backup
filter to capture fine dust that penetrates through the paper bag
filter. Lower-end vacuum cleaners have no backup filter and since
consumers cannot retrofit their vacuum cleaner with a backup
filter, they must suffer with dust emissions from their vacuum
cleaners. Vacuum cleaners employing paper bag filters without
backup filters provide such poor filtration that fine dust can be
visually found accumulating on the inside of the vacuum cleaner
housing that encompasses the paper bag filter. These dust emissions
can also reduce the vacuum cleaner's life by contaminating the
motor in the suction device.
[0006] The filtration efficiency of a paper vacuum cleaner bag of
the prior art is also reduced due to the design of the bag. In most
paper vacuum cleaner bags the dirt enters the bag inlet at a high
velocity and the dirt impacts the opposite wall of the bag. Thus
the high velocity dirt particles penetrate the porous paper media
resulting in low filtration efficiency.
[0007] Generally, paper bag filters need replacement monthly and
HEPA filters require replacement annually. Over the life of the
vacuum cleaner, the cost of replacement filters is often greater
than the original cost of the original vacuum cleaner. In addition,
it is of great inconvenience to the consumer to shop around
locating the proper size vacuum cleaner bag to fit their vacuum
cleaner. Moreover, disposable paper bag filters put unnecessary
waste in our environment.
[0008] Because paper filter media is very porous, fine dust is
traveling at a high velocity and it has a tendency of becoming
trapped in the pores of the paper bag. Therefore the paper bag
filter loses its permeability. As a consequence, the paper bag
filters have limited reusability. In fact, it is well known that
vacuum cleaners lose their ability to clean and pick up dirt as the
paper bag is filled. This is because the partially clogged paper
media restricts the airflow through the vacuum cleaner preventing
it from collecting dust deeply embedded in carpet fibers.
Therefore, most paper vacuum cleaner bag filters sold today are
sealed shut so that the contents cannot be emptied and the bag
reused.
[0009] U.S. Pat. No. 6,007,594 to Kaczor (1999) shows a multiple
use vacuum cleaner bag which is of paper media construction thus
offering poor filtration performance and limited reusability since
the paper media clogs with particulate with use and it cannot be
washed.
[0010] Vacuum cleaner bags of the prior art sometimes have
electrostatically charged media lining the inside of the paper bag
or consist of one thick layer of electrostatic media to improve the
filtration efficiency of the bag. Typically, these type bags
increase the filtration efficiency but not to the level of a HEPA
filter. This improvement in filtration efficiency, however,
decreases with time as the electrostatically charged sites on the
media, which capture fine dust particles, become covered with dust
and lose their ability to attract dust. Furthermore, these bags
become clogged and manufacturers recommend that they be replaced
when full.
[0011] Paper vacuum cleaner bags and the like are opaque and
therefore the contents of the bag cannot be visually inspected.
Consumers also have a tendency to overfill their paper bag filters.
They either forget to check their bag filter's contents because
they cannot see through the opaque paper or they intentionally try
to fill it completely to save money on purchasing replacement bags.
This not only adversely affects the ability of the vacuum cleaner
to clean their house, but it also frequently causes the bags to
burst. Storing dust in vacuum cleaner bags between uses also has a
tendency to develop strong odors. These offensive odors are most
noticeable when the vacuum cleaner is first turned on.
[0012] In cases of wet/dry vacs used in construction, heavy
materials such as cement and plaster dust can cause paper bags to
rip when lifted out of the vacuum cleaner. In addition, sharp
objects like nails, broken glass, wood chips etc. can cause paper
bags to rip while in use. Furthermore, paper bags deteriorate and
normally rip when liquids are collected.
[0013] As mentioned earlier, the poor filtration characteristics of
paper bag filters is generally compensated for by creating
multistage filtration systems comprised of a porous bag filter
followed up by a backup or series of backup filters. The prior art,
for instance, employs one of or a combination of electrostatic,
non-woven or microfiberglass filters as a backup filtration system.
These multistage filtration systems add significant cost and
complexity to a vacuum cleaner.
[0014] In order to deliver high filtration efficiency, vacuums
featuring multistage filtration systems require additional
mechanical seals between each filtration stage to ensure all the
air flowing through the vacuum cleaner is filtered and that no air
bypasses the filters. Moreover, the chambers that house each
filtration stage must be sealed to avoid leakage of dust through
cracks in the vacuum cleaner housing. These additional seals add
cost to manufacturing a vacuum cleaner and are the potential source
of failure in-use from gasket damage, dry rot, and so on. Upon
failure, these leaking joints in the vacuum cleaner not only can
cause dust leaks into the surrounding environment but they can also
decrease the suction of a vacuum cleaner and its ability to clean
debris located deep down in carpet fibers.
[0015] Vacuum cleaner bags cannot be manufactured from commonly
used high efficiency filter medias. If, for example, vacuum cleaner
bags were manufactured from microfiberglass like most vacuum
cleaners HEPA filters, the bags would be too brittle. Upon normal
handling and usage the fibers would break and cause leakage of dust
particles.
[0016] Vacuum cleaner bags also cannot be easily manufactured from
expanded polytetrafluoroethylene (PTFE) membrane in current bag
designs because current vacuum cleaner bag designs physically limit
the amount of filtration media that can be used to that which is
required to form a bag. This makes it difficult to adjust the
amount of media to compensate for using less permeable, high
efficiency media.
[0017] Many consumers already own vacuum cleaners that perform well
with the exceptions of needing replacement vacuum cleaner bags and
having low filtration efficiency. And there are consumers that have
a genuine need to improve the filtration efficiency of their vacuum
cleaner for health reasons and cannot afford the high-end vacuum
cleaners that come equipped with HBEPA filters. These consumers
have no attractive method to retrofit their vacuum cleaner with an
economical high efficiency vacuum cleaner bag.
[0018] The present invention addresses the aforementioned
limitations of the prior art by providing a high efficiency vacuum
cleaner bag fabricated of durable impermeable media having an
air-permeable particle separator and inlet: that can eliminate the
need for backup filters and complicated seals between filtration
stages, that is suitable for new vacuum cleaners as well as
retrofitting existing vacuum cleaners; that can have a re-sealable
vacuum cleaner bag opening for dumping contents of bag so that it
may be reused; that offers an improved design that reduces incoming
dirt velocity to improve filtration performance, that can feature
an antimicrobial treatment and absorbent filter to reduce odors
being emitted.
SUMMARY OF THE INVENTION
[0019] Accordingly, it is an object of the present invention to
provide an improved vacuum cleaner bag and method of operation for
a vacuum system such as a vacuum cleaner.
[0020] It is another object of the present invention to provide a
vacuum cleaner bag to retrofit existing vacuum cleaners with a high
efficiency filtration system.
[0021] Yet another object of the present invention is to reduce the
cost of operating a vacuum cleaner by providing an effective
reusable vacuum cleaner bag.
[0022] A further object of the present invention is to eliminate
the need for costly backup filters and the seals between each
filtration stage by providing a high efficiency, single-stage
vacuum cleaner bag.
[0023] An additional object of the present invention is to provide
a superior vacuum cleaner bag design that reduces the velocity of
the dirt entering the bag to improve filtration efficiency and life
expectancy of a vacuum cleaner bag.
[0024] A still further object of the present invention is to
provide a vacuum cleaner bag that solves the problem of odor in the
vacuum cleaner.
[0025] It is another object of the present invention to provide a
re-sealable vacuum cleaner bag open end.
[0026] Yet another object of the present invention is to provide a
vacuum cleaner bag that has a translucent media for inspecting the
contents of the bag so that it can be emptied at appropriate
intervals to sustain peak performance and avoid overfilling.
[0027] It is one more object of the present invention to provide a
durable bag construction that can collect sharp, heavy objects and
liquids without breaking.
[0028] Still one more object of the present invention is to
significantly reduce disposable, paper vacuum cleaner bag and
back-up filter waste and bring a positive impact on the
environment.
[0029] One more object of the present invention is to reduce the
time consumers spend shopping for replacement vacuum cleaner
bags.
[0030] Another object of the present invention is providing a
method of collecting dirt in a vacuum cleaner wherein dirt is
conveyed into a bag comprising durable impermeable media and dirt
is retained in bag cavity by an air-permeable particle separator as
clean air exits the bag.
DESCRIPTION OF FIGURES
[0031] FIG. 1 is a cross-sectional side view of one embodiment of
the present invention shown in an upright vacuum cleaner having a
hard vacuum cleaner bag case.
[0032] FIG. 2 is a front view of the vacuum cleaner bag shown in
FIG. 1.
[0033] FIG. 3 is a cross sectional side view of the vacuum cleaner
bag shown in FIG. 1.
[0034] FIG. 4 is a back view of the vacuum cleaner bag shown in
FIG. 1.
[0035] FIG. 5 is a cross sectional view of the air-permeable
particle separator shown in FIG. 1.
[0036] FIG. 6 is a back view of the air-permeable particle
separator shown in FIG. 5.
[0037] FIG. 7 is a cross sectional side view of an alternate
embodiment of a vacuum cleaner bag with an opening for emptying
contents in accordance with the present invention.
[0038] FIG. 8 is a back view of the alternate embodiment shown in
FIG. 7.
[0039] FIG. 9 is a cross sectional view of an alternate embodiment
of a vacuum cleaner bag opening for emptying the contents in
accordance with the present invention.
[0040] FIG. 10 is a cross sectional view of an alternate embodiment
of a vacuum cleaner bag closed bottom in accordance with the
present invention.
[0041] FIG. 11 is a cross sectional view of a alternate embodiment
of a vacuum cleaner bag opening for emptying the contents in
accordance with the present invention.
[0042] FIG. 12 is a cross sectional view of the vacuum cleaner bag
opening shown in FIG. 11 in open position.
[0043] FIG. 13 is a cross sectional view of one embodiment of
pleated filter media in accordance with the present invention.
[0044] FIG. 14 is a cross sectional view of an alternate pleated
filter media having a cover and pre-filter in accordance with the
present invention.
[0045] FIGS. 15-20 are front views and side views of alternate
embodiments of a vacuum cleaner bag in accordance with the present
invention.
[0046] FIGS. 21, 23, and 25 are cross sectional side views of
alternate embodiments of air-permeable particle separators in
accordance with the present invention.
[0047] FIGS. 22, 24, and 26 are back views of alternate embodiments
of air-permeable particle separators in accordance with the present
invention.
[0048] FIG. 27 is a partial cross-sectional side view of an
alternate embodiment of the present invention shown in an upright
vacuum cleaner having a soft case having a high inlet.
[0049] FIG. 28 is a partial cross-sectional side view of an
alternate embodiment of the present invention shown in an upright
vacuum cleaner having a soft case having a low inlet.
1 REFERENCE NUMERALS IN DRAWINGS 10. Vacuum cleaner bag 12. Vacuum
cleaner 14. Bag seal 16. Dirt tube 18. Dirt 20. Inlet 22.
Air-permeable particle separator 24. Hard bag cover 26. Top cover
seal 28. Bottom cover seal 30. Back cover seal 32. Clean air 34.
Exhaust 36. Impermeable media 38. Cavity 40. Frame seal 42. Frame
43. Flat Media 44. Pleated media 45. 46. Bag open end 48. Closure
mechanism 50. Bag closed-end 52. Removable-top 54. Top-frame 56.
Gasket 58. Bond 60. Permanent-bottom 62. Attached-lid frame 64.
Hinge 66. Attached-lid 68. Lid gasket 70. Male snap closure 72.
Female snap closure 74. Cover 76. Expanded PTFE membrane 78. Backer
80. Pre-filter 82. Incoming air flow 84. Soft bag 86. Top mount
dirt tube 88. Bottom mount dirt tube 90. Dirt tube o'ring
DESCRIPTION OF INVENTION
[0050] A typical embodiment of a vacuum cleaner bag 10 of the
present invention is shown in side view in FIG. 1 when installed in
an upright vacuum cleaner 12. The vacuum cleaner bag connects to
the vacuum cleaner by a bag seal 14 on a dirt tube 16 in an
essentially leak-proof manner. A dirt 18 is pneumatically conveyed
or pumped into the bag through an inlet 20. The dirt is normally in
the form of dust, allergens, hair, carpet fiber, lint, soil, grass,
leaves, wood chips, sand, liquids and other contamination. The air
that pneumatically conveys the dirt into the vacuum cleaner bag
enters the bag through the inlet and exits the vacuum cleaner bag
only through an air-permeable particle separator 22. A clean air 32
exits the vacuum cleaner through an exhaust 34.
[0051] The conveying air can be either pushed or pulled through the
bag depending on the location of the suction unit (not shown)
relative to the bag. A hard bag cover 24 attaches to the vacuum
cleaner at a top cover seal 26, bottom cover seal 28, and a back
cover seal 30. In appliances where the suction unit is pulling air
through the bag, the clean air may flow through the suction unit
before being exhausted from the vacuum cleaner. The clean air
provided extends the life of the motor driving the suction unit by
avoiding particulate contamination.
[0052] Bag seal 14 can be comprised of any material that will
retain a snug, airtight fit against dirt tube 16 over time.
Suitable materials are elastomeric such as urethane, vinyl,
plasticized PVC, dense foam, rubber, nitrile, plastics, cellulose,
dense cardboard or a combination of the preceding materials. The
bag seal can be adapted with a closure (not shown) to prevent dirt
18 from exiting the bag during removal from the vacuum cleaner and
while handling.
[0053] The vacuum cleaner bag of the present invention is shown in
front view in FIG. 2, side view in FIG. 3, and back view in FIG. 4.
The bag is formed of an impermeable media 36 having an interior
cavity 38 for storing the dirt. Suitable impermeable medias include
any durable film that essentially prevents airflow such as
polyethylene, polypropylene, vinyl, nylon, coated fabric, coated
paper, or other natural or synthetic materials. The thickness of
the impermeable media can vary from a completely flexible material
that allows inflation of the bag under use to a rigid material that
has a firm shape that does not change during usage.
[0054] The impermeable media can include antimicrobial treatments
to inhibit the growth of bacteria and mold in the bag. Antimirobial
treatments are available from Microban Products Company,
Huntersville, N.C. Antimicrobial treatments are incorporated by a
coating on the impermeable media or by compounding the additives
into the resin used to produce the impermeable media. Furthermore,
the impermeable media can be manufactured of translucent material
so that the contents of the bag can be inspected without
opening.
[0055] To prevent the buildup of static electricity on the vacuum
cleaner bag of the present invention, impermeable media 36 can be
further comprised of an anti-static coating. Alternate static
electricity controls could include a metallic fiber integrated into
impermeable media 36 or conductive fillers compounded into resin
producing the impermeable media.
[0056] Referring to FIGS. 3 and 4, the air-permeable particle
separator 22 is connected to impermeable media 36 over an exit hole
(not shown) in the back of the vacuum cleaner bag in an essentially
leak-proof manner using a frame seal 40. The seal surrounds the
perimeter of the air-permeable particle separator and closes the
gap between the air-particle separator and the impermeable media.
The seal can be achieved by heat fusion, adhesives, ultrasonic
welding, chemical bond or other methods known by those skilled in
the art of sealing.
[0057] Referring to FIGS. 5 and 6, air-permeable particle separator
22 is comprised of a frame 42 wherein a pleated media 44 is
installed in an essentially leak proof manner. Suitable materials
for producing the frame include cardboard and plastic materials
such as ABS, polycarbonate, polyethylene, polypropylene and so on.
The pleated filter media is sealed into the frame using heat
fusion, ultrasonic welding or adhesives such as hot melt glue or
polyurethane, for example. Generally flat media is pleated or
folded to increase the area of media installed in a constrained
space. In some applications it is necessary to separate the pleats
with glue beads (not shown) as known by those skilled in the art of
pleating. The glue beads keep the pleats open when under load from
the airflow. The pleats can be in a variety of configurations such
as triangular, curved, square, etc.
[0058] By employing pleated media, the present invention allows
designers to vary the amount of media used in air-permeable
particle separator 22. Thus, when designers use less permeable,
high efficiency media they have the flexibility to increase the
surface area of the air-permeable particle separator so that an
airflow restriction is not a consequence. As previously noted,
conventional vacuum cleaner bag designs limit media area to the
surface of the bag. If it is desirable to add media the bag has to
be made larger which most likely will not fit in the vacuum cleaner
housing.
[0059] As shown in FIG. 3, air-permeable particle separator 22
ideally is positioned so that the airflow-containing dirt entering
the inlet does not directly impinge on the air-permeable particle
separator. Positioning the air-permeable separator away from the
inlet allows the dirt particles to circulate in the bag and lose
energy so that the air-permeable particle separator has maximum
filtration effectiveness and experiences minimum damage.
[0060] Suitable filtration materials that can be used in the
air-permeable particle separator of the present invention include
expanded polytetrafluoroethylene (PTFE) membrane, microporous
foams, cellulose paper, cellulose/synthetic fiber paper blends,
electrostatically charged media, microfiberglass, nonwovens,
fabrics, felt, or combinations of, for example. Pleated media 44 is
optionally adapted antimicrobial.
[0061] It is particularly preferred to use expanded
polytetrafluoroethylene (PTFE) membrane as pleated filter media in
the present invention. A suitable PTFE membrane is available from
W. L. Gore & Associates, Inc., Newark, Del. or equivalent.
Pleated filter media comprising alternative materials generate less
desirable filtration performance and greater tradeoffs concerning
reusability.
[0062] FIG. 7 shows one embodiment of the present invention in side
view having a bag open-end 46 secured shut with a closure mechanism
48. As shown impermeable media 36 at the open-end is folded over at
least once and the folds prevent pressurized air inside the bag
from leaking out, especially when containing dirt. The closure
mechanism prevents the folds from opening and allowing pressurized
air to escape. The closure mechanism consists of a clamp that
applies pressure on the fold to prevent opening. The clamp can be
spring-loaded for added security.
[0063] Sealing and resealing the impermeable media can be achieved
in many ways. Suitable open-end designs that are re-sealable can
include, for example, interlocking plastic or elastic parts,
threaded lids, or lids with interference fit with the bag
opening.
[0064] Still referring to FIGS. 7 and 8, a bag closed-end 50 is
formed in a variety of ways known by those skilled in the art of
making bags. Typically, bottoms of bags are closed by folding and
sealing shut with adhesive. Other times they are sealed shut with
heat fusion. FIG. 8 shows the same embodiment in back view.
[0065] FIG. 9 shows in a cross sectional side view a second
embodiment of the bag open-end 46. A removable-top 52 is inserted
in a top-frame 54 with a gasket 56 that closes the gap between the
two components in an essentially leak-proof manner. The
removable-top and top-frame are generally injection-molded
components manufactured from thermoplastic materials, for example,
polyethylene, ABS, polypropylene, etc. Cardboard or the like can
also be utilized in lower life expectancy designs. Suitable gasket
materials include any elastomeric material that will retain its
resilient conformable properties over time such rubber, urethane,
nitrile, foam, etc. A bond 58 seals impermeable media 36 to
top-frame 54 in essentially a leak-proof manner. Acceptable bonds
of the present invention are realized through a variety of
techniques including heat fusion, adhesives, chemical bonding,
etc.
[0066] FIG. 10 shows in a cross sectional side view a second
embodiment of bag closed-end 50. A permanent-bottom 60 is sealed to
impermeable-media 36 in an essentially leak-proof manner with bond
58. Suitable permanent-bottom materials are injection-molded
plastic or cardboard.
[0067] FIG. 11 shows a third alternate bag open-end 46 of vacuum
cleaner bag 10 of the present invention. Attached-lid 66 is
connected to attached-lid frame 62 on one end by hinge 64. The
other end of the lid attaches by a male snap closure 70
interlocking with a female snap closure 72. A handle (not shown)
can be added to facilitate the opening and closing of lid. A
lid-gasket 68 seals the gap between attached-lid 66 and
attached-lid 62 in an essentially leak-proof manner. As shown,
lid-gasket 68 is a foam-in-place gasket normally produced of
urethane. Other suitable gaskets include plasticized PVC, foam,
rubber, etc. Many configurations of seals known by those skilled in
the art of sealing can be employed within the scope of the present
invention. FIG. 12 shows the same bag open-end 46 of vacuum cleaner
bag 10 in open position.
[0068] FIG. 13 shows in a cross-sectional side view preferred
pleated media 44. In this embodiment, the pleated filter media is
comprised of a two-layer laminate comprising an expanded
polytetrafluoroethylene (PTFE) membrane 76 and a backer 78.
Generally the airflow-carrying dirt contacts the expanded PTFE
membrane before flowing through the generally more porous backer.
The backer provides support to the very thin expanded PTFE
membrane. For additional strength, the expanded PTFE membrane is
optionally attached to the backer. Suitable backers are sheets of
porous polyester, nylon, paper, paper/synthetic blends,
polypropylene, etc. Attaching the backer to the expanded PTFE
membrane introduces the tradeoff of reduced permeability.
[0069] Expanded PTFE media in the present invention preferably is
greater than 90% efficient at 0.3 microns when tested at airflows
normally experienced in a vacuum cleaner for high-efficiency vacuum
cleaner bags. Those vacuum cleaner bags meeting HEPA standards
would employ expanded PTFE media rated at 99.97% at 0.3 microns.
Low efficiency vacuum cleaner bags of the present invention
employing PTFE membrane media would generally be in the 40-90%
efficiency range at the same test conditions.
[0070] Once again referring to FIG. 1, it is important to
understand that when the present invention employs high efficiency
pleated media 44 in combination with leak-proof bag seal 14, that
it is unnecessary to seal hard bag cover 24 to vacuum cleaner 12 so
that airflow is channeled to a backup filter. The airflow is
sufficiently cleaned in the vacuum cleaner bag of the present
invention and therefore does not require additional filtration.
Moreover, its durable construction eliminates the problem of bag
breakage and hence backup filters are not required to protect the
motor driving suction unit. This greatly simplifies vacuum cleaner
designs thus eliminating the need for expensive backup filters and
seals between filtration stages. Furthermore, it allows consumers
to retrofit existing vacuum cleaners with a high efficiency
filtration system.
[0071] FIG. 14 shows in a cross-sectional side view the pleated
filter media with a pre-filter 80 positioned between an incoming
airflow 82 and pleated media 44. The pre-filter provides multiple
functions including preventing large dirt from entering the pleats
and/or eliminating odor by optionally utilizing activated charcoal,
and/or providing a scent via odorant imbibed gel, plastic, foam,
netting etc to air exiting the vacuum cleaner.
[0072] It should be understood that the vacuum cleaner bag in the
present invention could be constructed in a variety of ways. For
instance, as shown in FIGS. 15-20, the air-permeable particle
separator can be installed over holes having a variety of locations
relative to vacuum cleaner bag inlet 20. FIG. 15 shows
air-permeable particle separator 22 installed in the front of the
bag; FIG. 16 shows air-permeable particle separator 22 installed in
the top of the bag; FIG. 17 shows air-permeable particle separator
22 installed in the bottom of the bag; and FIGS. 18-20 show
air-permeable particle separator 22 installed on the side or sides
of the bag.
[0073] The air-permeable particle separator can take on an infinite
variety of geometric shapes of which a few examples are
illustrated. FIG. 21 shows a side view of circular shaped
air-permeable particle separator 22 and FIG. 22 shows a back view
of the same circular shaped air-permeable particle separator. FIG.
23 shows a side view of an oval shaped air-permeable particle
separator and FIG. 24 shows a back view of the same oval shaped
air-permeable particle separator. FIG. 25 shows a side view of
rectangular or square air-permeable particle separator having a
flat media 43 instead of pleated media 44. FIG. 26 shows a back
view of the same rectangular or square air-permeable particle
separator having the flat media 43 installed in an essentially
leak-proof manner in frame 42. Suitable air-permeable particle
separators can also be, for example, flat panel (as shown), curved
panel (not shown) or a round cylindrical cartridge (not shown),
etc. Economical designs eliminate the frame and seal the fiher
media directly to the impermeable media. Air-permeable separator 22
can also be adapted to be replaceable.
[0074] FIG. 27 shows in a cross-sectional side view the vacuum
cleaner bag of the present invention installed in an upright vacuum
cleaner having a soft bag 84 surrounding vacuum cleaner bag 10. The
vacuum cleaner bag is attached to the vacuum cleaner by a top mount
dirt tube 86 as already described. FIG. 28 shows in cross-sectional
side view the vacuum cleaner bag of the present invention installed
in an upright vacuum cleaner having soft bag 84 surrounding vacuum
cleaner bag 10. In this case the vacuum cleaner bag of the present
invention is attached to a bottom mount dirt tube 88. The bag is
attached to the dirt tube in an essentially leak-proof manner using
a dirt tube o'ring 90.
[0075] The present invention applies to canister, central and
wet/dry vac classes of vacuum cleaners as well as upright vacuum
cleaners used in the previous illustrations. Furthermore, it is
anticipated that the present invention will be advantageous in all
appliances wherein large ranges of debris sizes are collected.
Examples include lawn mover clippings or leaf bags, leaf
collections system bags, woodshop dust collectors, carpet shampoo
machines, and power tool dust collection systems.
OPERATION
[0076] The manner of using the present invention is very similar to
using a paper bag filter in a vacuum cleaner. Referring to FIG. 1,
the operator of vacuum cleaner 12 removes (optional) hard bag cover
24 and if necessary removes the disposable paper bag filter.
Improved vacuum cleaner bag 10 of the present invention is
installed by securing bag seal 14 to dirt tube 16. The hard bag
cover is then reinstalled if vacuum cleaner is so equipped.
[0077] Dirt 18 is collected in the vacuum cleaner bag by turning
the suction unit (not shown) on and using the vacuum cleaner to
clean carpet, bare floors etc. The dirt is normally pneumatically
conveyed into the vacuum cleaner bag through inlet 20. The dirt
circulates in the bag interior until it settles to the bottom of
the bag and the air exits only through air-permeable particle
separator 22 leaving the dirt in the bag. Some fine dust becomes
air-entrained inside the bag and is stopped by the air-particle
separator.. Clean air 32 exits the vacuum cleaner into the room
without requiring additional filtration.
[0078] The odor of the dirt stored in the bag between uses does not
increase due to the antimicrobial treatment of vacuum cleaner bag
10 inhibiting bacteria and mold growth. Pre-filter 80 removes
residual odors, traps large dirt, or adds scent as air exits
vacuum.
[0079] When translucent impermeable media 36 is used, the operator
of the vacuum cleaner can easily inspect vacuum cleaner bag 10
contents by looking through the bag's outside cover. When opaque
impermeable media 36 is used the operator can gauge the fullness of
the bag by weight or by looking inside the bag through bag open end
46. As shown in FIGS. 7 and 8, to empty vacuum cleaner bag 10 it is
removed from the vacuum cleaner and closure mechanism 48 is
removed. The impermeable media is unfolded at bag open-end 46 and
dirt 18 is dumped out through the opening. If desired, the bag is
filled with water and the interior of the vacuum cleaner bag,
including the air-permeable particle separator, is washed with
water or water with detergent. Once the vacuum cleaner bag is dry
it is reinstalled and reused. Odor is also eliminated by dumping
the contents of the bag after each use or when convenient.
[0080] FIG. 9 shows a second alternate opening of vacuum cleaner
bag 10 of the present invention. To dump the contents of the vacuum
cleaner bag, the operator pulls removable-top 52 so that it
separates from top-frame 54. A handle (not shown) can be added to
facilitate this procedure. As the removable-top is moved away from
the bag, gasket 56 breaks the seal between removable-top 52 and
top-frame 54. Impermeable media 36 remains attached to top-frame 54
due to bond 58. The gasket is generally captive in either of the
aforementioned components. To reinstall the removable top after
dumping the bag contents, removable-top 52 is engaged with
top-frame 54 in a way that gasket 56 compresses and its resilient
elastomeric nature seals the gap between the two components in an
essentially leak-proof manner
[0081] FIG. 10 shows alternate bag closed-end 50 of vacuum cleaner
bag 10. Permanent-bottom 60 is attached to impermeable media 36 by
bond 58. Permanent-bottom 60 generally is a rigid material that
provides shape and structure to vacuum cleaner bag 10.
[0082] FIG. 11 shows a third alternate bag open-end 46 of vacuum
cleaner bag 10 of the present invention. Disengaging male snap
closure 70 from female snap closure 72, shown in FIG. 12, allows
opening attached-lid 66 by pivoting the lid around hinge 64 for
dumping contents of bag. A handle (not shown) can be added to
facilitate this procedure. Lid-gasket 68 breaks the seal between
attached-lid 66 and attached-lid frame 62. Impermeable media 36
remains attached to attached-lid frame 62 due to bond 58. The
gasket is generally captive in either of the aforementioned
components. As shown, a form-in-place urethane gasket utilizes it
resilient elastomeric properties to seal the gap between the two
components. To close attached-lid 66 after dumping the bag
contents, the attached-lid is repositioned within attached-lid
frame and locked in place with the snap closures. The gasket can
seal gaps between attached-lid 66 and attached-lid frame 62 in a
variety of configurations known by those skilled in the art of
sealing.
[0083] FIG. 13 shows preferred pleated media 44 in cross sectional
view. The airflow of the vacuum cleaner generally contacts expanded
polytetrafluoroethylene (PTFE) membrane 76 first and then flows
through generally more permeable backer 78 on its way through
air-permeable particle separator 22 (not shown). Typically, fine
particles become entrained in the air stream and float to the top
of the bag. Larger dirt settles to the bottom of the bag. The fine
dust particles are stopped by the highly efficient PTFE membrane's
surface and cleaned air exits the air-permeable particle separator.
The backer material provides support to the relatively thin PTFE
membrane. For extra support, the PTFE membrane can be attached to
the backer. Because of the non-stick nature of PTFE membrane the
dust cake which builds on the membrane surface can be easily
removed when emptying the bag. Moreover, for a more thorough
cleaning, the hydrophobic nature of the PTFE membrane allows the
bag to be filled with water or water and detergent so that the
interior of the bag and air-permeable particle separator can be
washed. Reversing the order of the backer and PTFE membrane so that
the airflow contacts the backer first falls within the scope of the
present invention but offer the performance tradeoffs of more
difficult cleaning and lower strength.
[0084] FIG. 14 shows a second alternate of pleated media 44 in a
multi-layer configuration wherein the airflow-containing dirt
contacts cover 74 before flowing through to reach expanded
polytetrafluoroethylene (PTFE) membrane 76 and then finally backer
78. Also shown in FIG. 14, (optional) pre-filter 80 is positioned
generally between incoming air flow 82 and pleated media 44. The
pre-filter stops larger particles from entering air-permeable
particle separator 22 or can serve as an odor remover stage if
comprised of, for example, activated charcoal. Pre-filter 80
positioned after pleated media 44 or in both locations with respect
to the airflow is considered within the scope of the present
invention and may provide benefits in odor removal in the post
position. By filtering-out the dust prior to removing the odor can
extend the life of the odor-removing filter. The pre-filter can
also add scent to exhaust in either position.
[0085] The present invention relates to bag filters that collect
dirt having a wide range of sizes. They are commonly used in vacuum
cleaners and other appliances such as lawn movers, leaf collectors,
shredders, carpet shampoo machines, woodshop dust collectors, power
tools and so on.
EXAMPLE 1
[0086] A vacuum cleaner bag of the present invention was
constructed by cutting 4 mil thick plastic sheeting (part number
70052 35002 manufactured by Carlisle Plastics, Minneapolis, Minn.)
into a 15" wide by 23" tall rectangular sheet. The sheet was folded
in half longitudinally and the bottom and side were sewn together
with all-purpose cotton covered thread on a Bemette 330 sewing
machine. The thread holes and seams were sealed with caulk and
allowed to dry. The bag was then turned inside out to improve its
appearance and give the sewn edge a more finished look. A
rectangular hole was cut out in roughly the position shown in FIG.
2 using a razor blade. An air-permeable particle separator made of
expanded polytetrafluoroethylene (PTFE) membrane and backer was
secured in the rectangular hole in a leak-proof manner with a
combination of glue and caulk. The polytetrafluoroethylene (PTFE)
membrane was facing the interior of the bag. The pleated media was
roughly 8 pleats/inch of about 3/4" depth. Approximately 2 sqft. of
media was included. The cardboard bag seal from a used Hoover Z
type vacuum cleaner bag (sku 73502 50781) was removed and secured
to the bag in the position roughly shown in FIG. 2 using a
combination of glue and caulk. The top open portion of the bag was
folded over several times and secured in a closed position with two
medium binder clips. The bag was installed in a Hoover Dimension
(model U 5209-930) vacuum cleaner by removing the hard cover and
sliding the bag seal over the dirt tube. The hard cover was
reinstalled.
[0087] The vacuum cleaner was used to pick-up dust on a heavily
soiled medium shag carpet. The vacuum cleaner with the prototype
bag previously described provided the same pick-up performance as a
new paper bag filter manufactured by Hoover. No dust was observed
in the interior cavity of the vacuum cleaner when the hard cover
was removed to inspect the bag. The bag was then removed, the
binder clips were removed, the bag was opened and the contents were
removed. For a thorough cleaning the bag interior was rinsed with
water and allowed to dry. The bag was then reinstalled in the
vacuum cleaner and the test was repeated. Similar pick-up results
were observed when the bag was reused after dumping and
washing.
[0088] While particular embodiments of the present invention have
been illustrated and described herein, the present invention should
not be limited to such illustrations and descriptions. It should be
apparent that changes and modifications may be incorporated and
embodied as part of the present invention within the scope of the
following claims:
* * * * *