U.S. patent application number 10/926758 was filed with the patent office on 2006-03-02 for hair ingestion device and dust protector for vacuum cleaner.
Invention is credited to Joseph P. Frantz, Richard H. Mertes.
Application Number | 20060042042 10/926758 |
Document ID | / |
Family ID | 35940931 |
Filed Date | 2006-03-02 |
United States Patent
Application |
20060042042 |
Kind Code |
A1 |
Mertes; Richard H. ; et
al. |
March 2, 2006 |
Hair ingestion device and dust protector for vacuum cleaner
Abstract
A hair ingestion device and dust protector for a vacuum cleaner,
and a combination of an end cap and a dowel assembly having a
thread cap, wherein a set of arms extends from the thread cap for
rotating with the dowel for deflecting threads to avoid
contamination of the bearing assembly included in the dowel
assembly. The thread cap also includes tapered vanes for
cooperating with an end cap to form a dust shield.
Inventors: |
Mertes; Richard H.;
(Fairview Park, OH) ; Frantz; Joseph P.; (Solon,
OH) |
Correspondence
Address: |
D. PETER HOCHBERG CO. L.P.A.
1940 EAST 6TH STREET
CLEVELAND
OH
44114
US
|
Family ID: |
35940931 |
Appl. No.: |
10/926758 |
Filed: |
August 26, 2004 |
Current U.S.
Class: |
15/392 |
Current CPC
Class: |
A47L 9/0455 20130101;
A47L 9/0477 20130101 |
Class at
Publication: |
015/392 |
International
Class: |
A47L 5/30 20060101
A47L005/30 |
Claims
1. Apparatus for keeping threads from moving to the bearing
assembly of a vacuum cleaner, the vacuum cleaner having a dowel for
rotating about the longitudinal axis of the dowel, said apparatus
comprising: a set of angularly spaced arms extending generally
radially from structure near the bearing assembly for rotating with
the dowel, said arms deflecting threads moving towards said arms
away from the bearing assembly.
2. A thread cap for rotating with a dowel in a vacuum cleaner for
deflecting threads away from said thread cap to avoid the
contamination of the vacuum cleaner by said threads, said thread
cap comprising: a support for rotating with the dowel, a set of
arms extending from said support in a direction generally away from
the longitudinal axis of the dowel, said arms being spaced from
each other for deflecting threads in the vicinity of said arms.
3. A thread cap according to claim 2 wherein said arms have free
ends spaced from said support, said free ends being configured for
deflecting threads away from said support in a direction generally
parallel to the axis of rotation of the dowel.
4. A thread cap according to claim 3 having an outer end for being
placed near the end of the dowel and an inner end, and said free
ends extend radially outwardly with respect to the dowel, said free
ends being partially concentric with the dowel and terminating in
concentric edges in the form of ramps inclined inwardly from the
outer end of said thread cap towards the inner end of said thread
cap for deflecting threads striking the respective ramps.
5. A thread cap according to claim 2 wherein the dowel has an
axially extending shaft and the vacuum cleaner has a bearing
assembly, and said thread cap is mountable on the shaft near the
bearing assembly for deflecting threads away from the bearing
assembly.
6. A thread cap according to claim 2 wherein the dowel has at least
one recess at an end of the dowel, and said thread cap is
configured to be mountable on the shaft within the recess.
7. A thread cap according to claim 6 wherein said thread cap
further comprises: a surface for being engaged by the bearing
assembly to position the bearing assembly relative to the
dowel.
8. A thread cap according to claim 6 wherein said thread cap
further comprises: a wall extending longitudinally with respect to
the longitudinal axis of the dowel in which said thread cap is
mountable, and tapered vanes extending from said wall and directed
towards the longitudinal axis for cooperating with other structure
to keep dust from contaminating a vacuum cleaner incorporating said
thread cap.
9. A thread cap according to claim 8 wherein the at least one
recess in the dowel is generally of a frusto-conical configuration
with the larger dimension being at the end of the dowel, and
wherein said thread cap further comprises: a relatively narrow
hub-portion for being placed inwardly in the dowel away from the
end of the dowel, said hub portion having an inner edge fixing said
hub portion to said shaft and an outer edge; and a relatively wide
annular flange longitudinally spaced from said hub portion, and
having an inner edge and an outer edge; wherein said set of arms
extends radially from said outer edge of said annular flange, and
said wall extends between said hub portion and said inner edge of
said annular flange.
10. Apparatus for a vacuum cleaner, said apparatus comprising: a
dowel assembly including: a rotatable dowel having a longitudinal
axis and opposite ends; a shaft extending from at least one end of
said dowel; a bearing assembly attached to said shaft, and a set of
angularly spaced arms extending generally radially with respect to
said dowel adjacent to said bearing assembly for rotating with said
dowel, for deflecting threads moving towards said arms away from
said bearing assembly.
11. Apparatus for a vacuum cleaner according to claim 10, wherein
said dowel assembly further includes: a support for rotating with
said dowel, said set of arms forming part of said support.
12. Apparatus for a vacuum cleaner according to claim 10 wherein
said dowel further includes: surfaces defining a recess at at least
one end of said dowel; and wherein said dowel assembly further
includes: a thread cap mounted on said shaft and being disposed in
said recess, said set of angularly spaced arms extending from said
thread cap.
13. Apparatus for a vacuum cleaner according to claim 12, wherein
said thread cap further comprises: a hub having a hole for fixing
said thread cap to said shaft; and wherein said support comprises:
a flange spaced from said hub and extending transversely to the
longitudinal axis of said dowel, said angularly spaced arms
extending from said flange.
14. Apparatus for a vacuum cleaner according to claim 13 wherein:
said surfaces defining a recess in said dowel define a recess
having a frusto-conical configuration; and said thread cap further
comprises a wall extending longitudinally with respect to the
longitudinal axis of said dowel between the outer edge of said hub
portion and the inner edge of said flange, said wall being
configured to rest in the recess of said dowel.
15. Apparatus for a vacuum cleaner according to claim 14 wherein
said hub includes a surface for locating said bearing assembly with
respect to said dowel.
16. Apparatus for a vacuum cleaner according to claim 14 wherein
the vacuum cleaner has a body, and wherein said apparatus further
comprises: an end cap located on an end of said dowel and fixed
with respect to the body of the vacuum cleaner, said end cap having
a collar for engaging a first portion of said bearing assembly to
fix said first portion to one body of the vacuum cleaner.
17. Apparatus for a vacuum cleaner according to claim 16 wherein
said bearing assembly is a ball bearing assembly having an inner
ring fixed to said shaft and an outer ring fixed to said collar of
said end cap.
18. Apparatus for a vacuum cleaner according to claim 16 and
further comprising a set of tapered vanes extending from said wall
and directed towards the longitudinal axis for cooperating with
said end cap to keep dust from contaminating the vacuum
cleaner.
19. Apparatus for a vacuum cleaner according to claim 18 wherein
said collar of said end cap has tapered configuration corresponding
to said tapered vanes, said thread cap rotating with said dowel
relative to said end cap to establish an air shield to keep dust
from contaminating said bearing assembly and for directing dust
from between said dowel assembly and said end cap to the ambient
air.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to apparatus for a vacuum
cleaner and, in particular, to a cap or to structure integral with
the dowel for preventing threads and other thin items such as both
hair and dust from reaching the bearings of a vacuum cleaner and
damaging the bearings and the vacuum cleaner itself, and for
preventing threads, hair and fibers from clogging or seizing the
rotation of the dowel which rotates in the head of the vacuum
cleaner.
[0003] 2. Description of the Prior Art
[0004] Various items are known for preventing or at least reducing
contaminants from reaching the bearings of a vacuum cleaner, these
bearings often being carried by the dowel assembly of a vacuum
cleaner, where the dowel assembly includes a dowel which rotates
about its longitudinal axis. The bearings can be of many types,
such as ball bearings or bushings, and other friction reducing
means. In a popular version of a vacuum cleaner, the dowel has
radially extending tufts of bristles or the like, and the dowel
assembly is rotated by means of a belt which is driven by the
vacuum cleaner motor. In another version, the dowel assembly is
rotated by a motor-driven gear chain. Some of the persistent
contaminants of vacuum cleaner bearings are thread, hair, fibers
and the like (hereinafter sometimes referred to as "thread"). One
attempt to prevent thread from reaching the bearings is the
provision of felt on the ends of the dowel, which acts as a barrier
to block some thread from passing to the bearings and/or from
clogging the dowel. However, the felt has been found to simply
accumulate thread, and some thread either breaks from being held by
the felt or passes through the felt and is carried to the bearings
and/or may contribute to seizing the dowel. Another attempt to keep
thread from moving to the bearings or clogging the dowel is a
cylindrical wall which extends from a disk overlapping the end of
the dowel assembly and extends toward the center of the dowel
assembly for acting as a shield or labyrinth for barring the
threads from reaching the bearings or clogging the dowel. However,
this type of shield is not effective since potentially damaging
threads bypass the cylindrical wall.
[0005] The thread problem is serious in the vacuum cleaner
industry, and various companies have established hair ingestion
tests in which particular amounts of hair are spread over a
prescribed area. In order to pass the test, a vacuum cleaner is
required to prevent the operating vacuum cleaner from picking up
the hair and transferring it into the bearing assembly and/or
clogging the dowel in the end of the dowel assembly. Passing these
tests has been a serious problem in the vacuum cleaner
industry.
[0006] The problem of dust invading the end of the dowel of a
vacuum cleaner and potentially causing damage to the bearings was
solved as set forth in Ser. No. 10/375,747 filed Feb. 26, 2003 by
the present inventors. In the preferred embodiment of that
application, a set of vanes rotating with the dowel cooperate with
an appropriately configured end cap to in effect set up an air
barrier while expelling dust in the vicinity.
SUMMARY OF THE INVENTION
[0007] An object of the present invention is to provide an improved
apparatus for protecting a vacuum cleaner from contaminants.
[0008] Another object is to protect a vacuum cleaner from
threads.
[0009] Still a further object of the invention is to prevent
threads from damaging the bearing assembly of a vacuum cleaner.
[0010] It is a further object to prevent threads from clogging or
seizing a dowel in vacuum cleaners.
[0011] It is an additional object to protect the bearing components
held in the dowel assembly of a vacuum cleaner from threads.
[0012] Yet still another object is to provide apparatus for
substantially preventing threads from contaminating the bearings in
the dowel assembly of a vacuum cleaner.
[0013] It is also an object to provide apparatus for preventing
threads from impairing the operation of bearing assemblies in
vacuum cleaners, which apparatus is economical to fabricate and
install, and effective in use.
[0014] Another object is to provide a device for effectively and
efficiently preventing hair and dust from contaminating the
bearings and/or from clogging the dowel of a vacuum cleaner.
[0015] An additional object is to provide an improved device for
both preventing threads from impairing the operation of a vacuum
cleaner and for preventing dust from also preventing the proper
operation of a vacuum cleaner.
[0016] These and other objects will become apparent from the
description to follow and from the appended claims.
[0017] The foregoing objects of the present invention are achieved
by the preferred embodiment of the invention. Many vacuum cleaners
incorporate a dowel assembly having a dowel with tufts of bristles
extending generally radially therefrom for picking up dirt,
including dust and thread, as the dowel rotates about its central,
longitudinal axis. An axially-extending rod extends from each end
of the dowel portion of the dowel assembly, and the dowel rotates
with the rod(s). The dowel assembly is rotated by a belt, gear
train or the like, which is driven by a motor. The dowel assembly
has a dowel which is usually recessed at its opposite ends. A
bearing assembly is located in the respective recesses, and the
bearing assembly engages both the rod(s) during rotation of the
dowel and structure fixed relative to the body of the vacuum
cleaner, such as an end cap, for reducing friction between the
dowel and the fixed structure. The end cap covers an end of the
dowel assembly and has an inner collar configured to fit into the
recess and to engage the fixed portion of the bearing assembly. The
hair (or thread) ingestion device and dust protector according to
the preferred embodiment includes a thread cap. The thread cap is
seated inside each recess of the dowel and sits against an end wall
of the dowel perpendicular to the longitudinal axis of the dowel.
The thread cap has an annular shoulder for locating the bearing
assembly which is mounted on the rod. The thread cap has an annular
flange from which extend radial arms. The radial arms can lie in a
common plane which is perpendicular to the longitudinal central
axis of the dowel. The arms may also be referred to as skirts,
tangs or deflector paddles. Each arm is defined on its radial sides
by a pair of generally radial edges which are referred to herein as
ramps. The respective arms are separated by a space having no arms,
the spaces being referred to as "slots." The arms set up a barrier
to prevent thread from moving to the bearing assembly. The number
of arms is not crucial, but an inventive end cap with eight arms
has been found to be very effective.
[0018] The thread cap has a generally frusto-conical wall defining
a recess, and generally radial vanes extend from the latter wall
into the recess. The outer walls of the collar of the end cap
cooperate with the vanes to form a dust protector.
[0019] Alternatively, the foregoing structure could be incorporated
as an integral part of the dowel, or as a separate piece or pieces
attached to the dowel. Likewise, some components could be integral
with the dowel, and others could be part of an insert in the
dowel.
[0020] The dowel assembly rotates about its central axis as it is
driven by the driving assembly operated by the vacuum cleaner
motor. The rotating deflector arms or paddles, accompanied by the
slots, deflect threads and prevent the threads from entering the
recesses at the end of the dowel assembly and stop the threads from
reaching the bearing assembly or from clogging (i.e. seizing) the
dowel. The vanes cooperate with the collar of the end cap to
establish an air shield transverse to the longitudinal axis of the
dowel and to apply centrifugal force to dust particles to drive
them from the recess in the dowel and to the ambient
atmosphere.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] FIG. 1 is a part perspective view of a dowel assembly for a
vacuum cleaner, showing an end cap with a portion cut away to show
a portion of the invention.
[0022] FIG. 2 is a side view of the apparatus shown in FIG. 1.
[0023] FIG. 3 is a perspective view of a thread cap according to a
preferred embodiment of the invention.
[0024] FIG. 4 is an alternate thread cap according to the
invention.
[0025] FIG. 5 is a cross-sectional view of a dowel assembly with a
thread cap as shown in FIG. 3, and an end cap.
[0026] FIG. 6 is a bottom view of a portion of a vacuum cleaner
with a dowel assembly and end caps incorporating the present
invention. The cover of the vacuum cleaner has been removed to
reveal the foregoing parts.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0027] Referring first to FIG. 1, one end portion of a dowel
assembly 10 is shown on which is mounted an end cap 30. Dowel
assembly 10 incorporates a dowel 12. Dowel 12 is shown as being
belt driven and has a pair of annular recesses 14 with radial
sidewalls 16,18 to collectively form a pulley 19 having a rim 21
for receiving a motor driven drive belt. An annular side end
portion 20 of dowel 12 has generally radial tufts of bristles 22
extending therefrom for picking up such dirt as dust and threads
coming in their path as dowel 12 is rotated by the vacuum cleaner
motor. Tufts of bristles 22 are of a type known in the art. The
portion of the dowel assembly is shown in FIG. 1, and the opposite
end is nearly identical in configuration and components, although
usually only one part of the assembly is provided with the
structure for rotating the dowel.
[0028] Dowel 12 rotates about a rod or shaft 24 running along the
central longitudinal axis of dowel 12. Rod 24 could extend through
the entire length of dowel 12 through a bore 26 extending along the
length of dowel 12, or there could be a pair of rods which is
disposed at an axial end of dowel 12, in which case bore 26 would
be closed to properly locate each rod 24. Dowel 12 and rod(s) 24
are fixed to each other. A thread cap 28 is mounted on the free end
of rod 24 extending from a recess in dowel 12 as explained below,
and end cap 30 covers the end of dowel assembly 12. As explained
later, end cap 30 functions both as a contributing part of a dust
shield and as a bearing assembly holder. A bearing assembly 32 is
also mounted on the end portion of rod 24 as also discussed below,
and end cap 30 has a cylindrical inner collar 34 which engages
bearing assembly 32 to hold one part as discussed later. End cap 30
has an outer cylindrical wall 36 which helps to prevent dust from
entering the end portion of dowel assembly 10. End cap 30 is fixed
relative to the body of the vacuum cleaner in which dowel assembly
10 is mounted.
[0029] The side view of FIG. 1 is shown in FIG. 2. FIG. 2 shows one
end part of dowel assembly 10 with dowel 12, annular recess 14 with
sidewalls 16,18, annular side end portion 20 and tufts of bristles
22. The side of thread cap 28 is shown. End cap 30 covers the end
portion of dowel assembly 10.
[0030] Thread cap 28 is shown in detail in FIG. 3. Thread cap 28
comprises a support 29 which is generally frusto-conical in shape,
having a frusto-conical wall 39 tapering outwardly from a
relatively small in diameter inner hub 40 to the relatively large
inside circular portion or inner edge 42 of an annular flange or
support 44. Hub 40 has a hole 43 for fitting over rod 24. Thread
cap 28 has an inside surface or inner end wall 41 being seated in
the recess of dowel 12 and a bearing seating surface 45 upon which
a bearing assembly can be seated. Thread cap 28 incorporates a set
of vanes 46 extending along the inner surface of frusto-conical
wall 39 for cooperating with collar 34 of end cap 30 to prevent
dust from contaminating bearing assembly 32 (as described in
principle in co-pending U.S. Ser. No. 10/375,747 filed Feb. 26,
2003 cited above), although in the latter application the vane
structure is on the dowel and not on a thread cap as is presently
being discussed. Vanes 46 extend radially inwardly from wall 38 and
are inclined outwardly from the outer edge of hub 40 to the inner
edge of flange 44 to set up an air movement which both bars dust
from moving towards hole 43 and bearing assembly 32, and for
establishing a centrifugal force to eject dust from between thread
cap 28 and end cap 30 to the ambient air. Eight vanes 46 have been
found to work well, but other numbers may work as well. There may
be situations where vanes 46 are not required, and they could be
removed; however, arms 46 will function according to the invention.
The structure without the vanes is shown in FIG. 4.
[0031] Referring to FIG. 5, collar 34 has an outer (away from the
longitudinal axis of end cap 30) wall 47 which is inclined by the
same amount as vanes 46, but collar 34 terminates in the radial
direction prior to its entering the space between vanes 46. Wall 47
defines a volume with the interior of thread cap 28 with vanes 46
for establishing a dust or air shield to prevent dust from flowing
to the bearing assembly and for defining a path for the dust to be
forced from the dowel assembly and the end cap by centrifugal
force.
[0032] However, whereas the flange corresponding to flange 44 in
FIG. 3 in Ser. No. 10/375,747 is relatively narrow, flange 44 is
wider and it carries radially-extending angularly (and preferably
equiangularly) spaced arms 48. Each arm 48 is defined on its
generally radially oppositely disposed sides by ramps 50,52 and at
its free end by an outer edge or free end 54. Ramps 50,52 are
angled to prevent threads from clogging or seizing the rotation of
dowel 12, or contaminating the bearing assembly. Viewing FIG. 3,
when thread cap 28 rotates clockwise as shown by arrow A, threads
moving between any of ramps 50 and 52 are engaged by ramp 52 and
deflected in direction C generally parallel with the axis of
rotation of dowel 12 and away from the bearing assembly. Likewise,
when thread cap 28 is rotating counterclockwise in Direction B,
threads are engaged by a ramp 50 and also deflected in direction C
away from the bearing assembly. The angle .theta. of ramps 50,52
should be between 30.degree.-60.degree., although other angles and
configurations are within the scope of the invention. For example,
.theta. could be 0.degree., the ramps could each have a variety of
configurations within each ramp, and each pair of ramps facing each
other could have different configurations. The depth of arms 48
depend upon the nature of the dowel assembly, the characteristics
of thread cap 28, the nature of the threads expected to be
encountered, and other variations depending on the nature of the
vacuum cleaner. Moreover, arms 48 need not extend radially from
outer end 53 of thread cap 28.
[0033] Still considering arms 48, each arm 48 extends from an outer
end 53 of thread cap 28, outer end 53 being nearest the end of
dowel 12 when inner hub 40 at an inner end 55 is inserted into the
end portion of dowel 12. Flange 44 is at outer end 53. Free ends 54
lie in an imaginary cylindrical surface concentric with the axis of
dowel 12, with each end 54 being partially concentric with that
axis. Ramps 50,52 are therefore concentric with the axis of dowel
12 and are inclined inwardly from outer end 53 towards inner end
55. In other words, the projection of ramps 50,52 on the respective
arms 48 would meet in the direction of the inner end 55 of end cap
28. Edges 54 are preferably curved and concentric with the
longitudinal, central axis of bore 26. Flange 44 and arms 48 are
advantageously planar, and the plane is perpendicular to the axis
of bore 26.
[0034] Inner hub 40 of thread cap 28 includes bearing seating
surface 45 for seating bearing assembly 32 in the recess of dowel
12. Surface 45 is on a relatively thick inner cylindrical part for
providing strength to thread cap 28 as well as to provide an
increased area of thread cap 28 for the rod in the dowel to
engage.
[0035] FIG. 5 shows the invention in a slightly different, but
similar, dowel assembly 100 for a vacuum cleaner. The same
numerical designators will be used as in FIGS. 1 and 2, but a
different pulley 60 is used and cutting channels are incorporated
as explained below. Pulley 60 is fixed in dowel 12, which is
engaged by a belt driven by the motor for the vacuum cleaner to
rotate dowel 12 about rod 24. The end of dowel 12 as shown includes
tapering sidewall 62 and an end wall 64, for defining a recess in
the end of dowel 12 (there are like structures at both ends of
dowel 12). Bore 26 extends through dowel 12 to accommodate rod 24
which rotates with dowel 12. Dowel 12 further includes cutting
channels 66,68 in which scissors or other cutting device can be
inserted to cut thread wound about dowel 12 to facilitate removal
of the thread.
[0036] Bearing assembly 32 is a ball bearing assembly (although
other bearing assemblies such as bushings could be used) and is
composed of an inner ring or race 70 having an axial hole with an
inner diameter generally equal to the diameter of rod 24 so that
ring 70 will rotate with rod 24, an outer ring or race 72 with an
outer diameter, and a set of bearing balls 74. Inner hub 40 of
thread cap 28 has bearing surface 45, and inner ring 70 sits on
surface 45. As discussed below, outer ring 72 is fixed with respect
to end cap 30.
[0037] Thread cap 28 is shown as being seated in the recess in the
end of dowel 12. Wall 39 of thread cap 28 and tapering sidewall 62
of dowel 12 are configured to nest together. Thread cap 28 has its
inner end wall 41 which is seated against end wall 64 of dowel 12.
Thread cap 28 is shown having inwardly extending vanes 46 and
outwardly extending flanges 44 with arms 48.
[0038] End cap 30 is mounted across the end of dowel assembly 100
and has protrusion 76 having an inner recess defined by inner
cylindrical wall 78 and inner protrusion end wall 80. Protrusion 76
receives the end of rod 24. End cap 30 further has an inner
shoulder 82 engaging the end of outer ring 72 of bearing assembly
32. Collar 34 has an interior bore 84 for engaging outside surface
86 of bearing assembly 32 by means of a press fit. By this
arrangement, the rotation of dowel 12, rod 24, thread cap 28 and
inner ring 70 is effected, and end cap 30 and outer ring 72 of
bearing assembly 32 are stationary with respect to the foregoing
rotation.
[0039] Dowel 12 is preferably made by injection molding of an
appropriate plastic, although wood or metal could also be used.
Injection molding is advantageous in that it provides fast,
consistent results and yields a product of even density that may
not require rotational balancing. Thread cap 28, end cap 30 and
pulley 106 shown in FIG. 5, are also preferably made from an
appropriate plastic by injection molding, and various pulley
designs are possible depending on the driving device. Appropriate
plastics include nylon, glass-filled nylon, ABS and the like. Metal
pulleys are also possible.
[0040] FIG. 6 shows a dowel assembly 100 with end caps 30 mounted
in a vacuum cleaner 102. Dowel assembly 100 is rotated by a belt
104. Belt 104 is rotated by a shaft 106 which is rotated by the
vacuum cleaner motor. Tufts of bristles 22 perform the cleaning
operation. End caps 30 are fixed relative to the body of vacuum
cleaner 102 by means of sole plates 108 which fixedly engage
protrusions 76 of end caps 30. While dowel 12 is shown as being
rotated by belt 104, other means for rotating a dowel are known. In
addition to a gear train mentioned earlier, the dowel could be
rotated by airflow, a motor within the dowel, a worm gear, an
electrical device or by a shaft.
[0041] In operation, dowel 12 is rotated about its longitudinal
axis by the drive belt 104, gear drive or the like. Considering
first the threads which could damage bearing assembly 32, thread
cap 28 rotates with dowel 12. Radially-extending arms 48 deflect
threads, which might otherwise work their way between end cap 30
and bearing assembly 32, and prevent them from damaging the bearing
assembly. The deflected threads may be wound about dowel 12 or may
be deflected entirely away from the vacuum cleaner.
[0042] Turning to the dust, the rotation of thread cap 28
establishes air turbulence in a cavity 86, around the inner portion
of collar 34 to its termination at outer cylindrical wall 36. This
turbulence provides a barrier to dust which otherwise could flow
through the cavity and contaminate the bearing assembly. Any dust
that happened to be in or around the bearing assembly would be
expelled by centrifugal force.
[0043] The invention thus provides a very effective yet inexpensive
way to prevent both threads and dust from contaminating the bearing
assembly. The invention can be made through injection molding of
appropriate plastics using known manufacturing techniques. Plastic
has been found to be a preferable material, but other materials
such as metal, wood, glass fibers and the like could also be used.
Although the preferred embodiment of the invention showed the arms
and vanes as being part of the thread cap, the invention also
encompasses the arms and/or vanes being integral with the
dowel.
[0044] The invention has been described in detail, with particular
emphasis on the preferred embodiments thereof, but variations and
modifications may occur to those skilled in the art to which the
invention pertains from the foregoing specification and drawings,
and the appended claims.
* * * * *