Note: Descriptions are shown in the official language in which they were submitted.
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ACUUM ~LE~NING TOOL WIT~I ADJUSTA~LE INTAKE AIR FL~W
Background of the Invention
The present invention relates to a vacuum
cleaning tool having a housing, in a base of which
is provided a suction or intake opening for a
suction or intake air flow to a vacuum cleaner, the
tool also having a brush roller, bristles of which
extend through the intake opening, with the brush
roller being rotatably driven via an air turbine
that is driven by the intake air flow, wi-th this
intake air flow belng guided from the intake
opening to the air turbine and to a connector of
the vacuum cleaning tool via a flow opening.
When vacuum cleaning textile floor coverings
and smooth floor surfaces, in order -to loosen dirt
particles that adhere to the surface that is being
cleaned a rotatabl~ drlven brush roller is used
that is disposed in the vacuum cleaning tool, with
bristles of the brush roller extending through the
intake opening. To clean various textlle floor
cov~rings, and to achleve an op-timum cleaning
effect at maximum protectlon of the floor covering,
the intensity of the suction or intake alr flow
must be ad~ustable, as a conse~uence of whlch the
speed of the brush roller will also be altered.
It is known to ad~ust the intake alr stream by
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altering the speed of the suction fan motor via
electrical or electronic adJustment means.
However, this type of adJustment of the intake air
stream is technically complicated and 0xpensive,
and is -therefore used only for large, high-quali-ty
vacuum cleaning apparatus.
It is also known to reduce the in-take alr flow
through the intake opening of the vacuum cleaning
tool vla a so-called secondary air stream. For
this purpose, a manually operable adjustment device
is disposed in the vacuum hose in the vicinity of
the handle for opening and closing a secondary flow
opening. Unfortunately, this quite slmple
adJus-tment device permits only very course
ad~ustment of the in-take air stream, which is often
inadequate.
It is therefore an obJect of the present
invention to improve a vacuum cleaning tool of the
aforamentioned general type ln such a way that the
intake alr stream, and hence also the speed oE the
brush roller that i8 driven by the air turbine, can
be easily and sensitively adJusted.
~rief Description of the Drawings
This obJect, and other objects and advantages
of the present invention, will appear mor~ alearly
~rom the following specification in con~unction
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with the accomparlylng schematic drawings, in which:
Fig. 1 is a cross-sectivr-al view
through one exempl ary
embodiment of the inventive
vacuurn cleaning tool at the
level of a main Elow opening
and a secondary flow opening,
Fig. 2 is a partially bro}cen-away
front view of the vacuum
cleaning -tool of Fig~ 1;
Fig. 3 is an enlarged view oE the
slide mechanism and control
plate disposed in the vacuum
cleaning tool, and in
particular with the main flow
opening completely open;
Fig. 4 is a view similar to Fig. 3
with the side slide mechanism
lowered to reduce the passage
cross-sectlon of the main flow
openincJ;
Fig. 5 is a view similar to Fig~ 4,
with the midd1e ~1ide
mechani.sm half way lowered;
and
Fig. 6 is a view slmilar to Fig. 5,
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with the middle slide
mechanlsm completely lowered.
Summary of the Invention
The vacuum cleaning tool of the presant
invention is characterized primarily by at least
one slide mechanism that ~s disposed ~n the housing
for varying a passage cross-section of the main
flow opening and hence for adJusting the volume of
the in-take air flow.
Advan-tageously, two slide mechanisms are
provided for being able to ad~ust the passage
cross-section of the main Elow opening; thesa two
slide mechanisms are preferably coupled with ons
another in an adJustment path dependent manner.
Pursuant to a further specific embodiment of
the present invention, one of the slide mechanisms
has two tongues that are associated with the end or
side portlons of the flow opening, while the other
slide mechanism is associated wlth the central
portion of the flow openlng and ls disposed between
the tongues of the one slide mechanism. This
configuration makes it possible to leave the
passage height of the main flow opening unaltered
after the side slide mechanism that is provided
with the tongues has been lowered, so that even
large dirt particles can still ba drawn in without
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difficulty.
~y means of the slide mechanism arrangement~
it is possible -to completely interrupt the intake
air stream through the intake opening, in which
connection it is advan-tageous to at the same time
open a secondary flow opening through which a
secondary air stream flows from an intake opening
-to the air turbine, thereby maintaining the
rotating drive for the brush roller.
Further specific features of the present
lnvention will be descrlbed in de-tail subsequently.
Descrlption of Preferred Embodiments
Referring now to the drawings in detail, the
vacuum cleaning tool 1 has a housing 2 in the
forward region of which is formed a brush chamber
3. Disposed in the base 6 of this brush chamber is
a suction or intake openlng 19 that faces the floor
surface 17 that is to be cleaned: the intake
opening l9 extends over the entire width of the
vacuum cleaning tool 1. Disposed in the brush
chamber 3, above the intake opening 19, i9 a brush
roller 4, the br:Lstles 5 of which pro~ect beyond
the intake opening 19 and thuæ come into con-tact
with the floor surface 17 that is to be cleaned.
The brush roller 4 is driven by an air turbine
lO via a belt 7, the turbine wheel 11 of the
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tu-bine is mounted in the main housing 2 in such a
way as to be rotatable about a horizontal sha~t 12.
In its end or rear portion 8, which is remote
from the brush chamber 3, the housing 2 of the
vacuum cleaning tool 1 is provided with a pivotably
mounted connector 9 via which the vacuum cleaning
tool is connected to a non-illustrated vacuum
cleaner.
The suction or in-take air stream of the vacuum
cleaning -tool flows via the intake opening 19,
which rests upon the floor surface 17 that is to be
cleaned, into the brush chamber 3, and from there
via a flow opening 15 into a flow channel 16, whlch
conveys the in-take air stream tangentially relative
to the turbine wheel 11; the intake air stream then
flows off to the vacuum cleaner via the connector
9. Provided parallel to the maln flow opening 15
in the housing 2 oE the vacuum cleaning tool 1 is a
secondary flow opening 38; this secondary flow
opening receives outside air via a slit-like
suction or intake opening 39 that is provided in
the housing 2, with the air then flowing -to the
connector 9 via an air inlet opening 37 and the
turbine wheel 11.
To ad~us-t the volume of the intake air stream
that en-ters via the intake opening 19, and hence
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also to adjust the speed of the air -turbine 10 -that
drives the brush roller 4, a sllde mechanism
arrangemen-t 41 is provided in the brush chamber 3
upstream of the main flow openlng 15. The
advantage of disposing the slide mechanism
arrangament 41 upstream of the maln flow opening 15
and the secondary flow opening 38 is that the slide
mechanism can be pressed by the intaka air stream
against the rim of the flow openings 15 and 38,
-thus ensuring a tight closing-ofE without the need
for additional measures.
The construction of the slide mechanism
arrangement 41, which is shown in cross-section in
Fig. 1, can be seen more clearly from Fig. 2. The
flow opening 15 has an essen-tially square or
rectangular cross-sectional conflguration and, when
seen in the front view oE Fig. 2, is disposed
centrally in that wall of -the housing 2 -that
separates the housing from the brush chamber 3.
The cross-sec-tional conEiguration of the flow
channe]. 16 corresponds to that of the main Elow
opening 15.
The slide mechanism arrangement ~1 comprises
an approximately U-shaped sida slide mechanism 20,
the legs of which are embodi~d as tongues 21 and 22
for covering the side portions 13 and 14 of the
2 ~
main flow opening 15. The U-shaped slide
mechanism, which will subsequently be designated as
the side slide mechanism 20, is held in -the houslng
in such a way that it can be displaced vertical].y
relative to the horizontal longltudinal central
axis 31 of the main flow opening 15.
Provided between the tongues 21 and 22 of the
side slide mechanism 20 is a middle slide mechanism
25, which in order to close oEf the central portion
18 of the main flow opening 15 is held in the
housing in such a way as to be displaceable
vartically relative to the longitudinal central
axis 31 of the main Elow opening 15. Via
respective pins 26 and 27, the two slide rnechanisms
engage in respective guide slots 28 and 29 of a
control plate 30, which is mounted in the housing
in such a way as to be displaceable in guide rails
33 and 3~ in the d:Lrection of the longitudinal
central axis 31 of the main flow opening 15. The
control plate 30 is provided with a grip rnember 35
that extends out through a slot that forms the
intalce opening 39 for the secondary flow opening
38. Associated with the grip member 35 are
ad~ustment mar}ss 40 that are provided on the
housing.
In the open position of the main flow opening
2 ~
15 shown in Fig. 3, the two slide mechan:Lsms 20 and
25 are disposed above -the opening 15. In relat~on
to -the main Elow opening 15, the middle slide
mechanism 25, in its "open position", completely
uncovers the main flow opening 15; at the same
time, however, in the open position o the main
flow opening 15 the middle slide mechanism 25
closes off the secondary flow opening 38, as shown
by broken lines in Fig. 1. In this position
illustrated in Fig. 3, the pin 26 of the side slide
mechanism 20, and the pin 27 of -the middle slide
mechanism 25, are disposed in end portions 28a and
29a of the guide slots 28 and 29 r0spectlvely.
These end portions 28a and 29a are disposed
essentially parallel to the longltudinal central
axls 31 oE the main flow opening 15. The vertical
or heigh-t positions of the end portions 28a and 29a
of the guide slots 28 and 29 determine the open
positlons of the side slide mechanism 20 and the
middle slide mechanism 25 illustrated in Fig. 3.
The end portion 28a of the guide slot 28 has a
horizontal dimens:lon that essentially corresponds
to the dlameter of the gu:lde pin 26. The other end
portion 28b of the guide slot 28 is disposed
parallel to the end portion 28a, but is lower by
the vertical distance "u", which corresponds to the
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stroke or travel of the side slide mechanlsm 20
from its open posltion shown in Fig. 3 -to its
closed position shown in Figs. ~ to 6. The two
horizontal end portions 28a and 28b mer~e with one
another via an inclined portion 28'.
When viewed from the top, the hori~on-tal end
portion 29a of the guide slo-t 29 that is associated
with the middle slide mechanism 25 has a length
that corresponds appro~imately to the leng-th of the
end portion 28a plus the inclined portion 28'.
When the control plate 30 is moved in the direction
o~ the arrow P, the pin 27 is gulded in the
horizontal end portion 29a, as a result of which
the middle slide mechanism 25 remains in its open
position. In con-trast, after a short ad~ustment
path o~ the control plate 30, tha pin 26 o~ the
slde slide mechanism 20 leaves the end portion 28a
and en-ters the inclined portion 28', being shifted
by the distance "u" until it reaches the lower
horizontal end portion 28b, as a result o~ which
the side slide mechanism 20 is displaced into i-ts
closed position i:llustrated in ~ig. 4. Whereas the
side slide mechanism 20 in -the closed position
s}lown in Fig. 4 has thus closed off the end or side
portions 13 and 14 o~ the main flow opening 15, the
middle slide mechanism 25 maintains i-ts open
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position, in which it close.s off tha secondary flow
opening 38. The passage cross-section of the main
flow opening 15 is reduced by the side portions 13
and 1~ that are covered by the tongues 21 and 22 of
the side slide mechanism 20; in conformity with the
reduced intake air stream, the drive speed of the
air turbine 10 is reduced, so that the brush roller
4 rotates mor~ slowly. The height of the main flow
opening 15 advantageously remains unaltered, so
that larger dirt particles that are drawn-in with
the reduced volume intake air stream are also
reli.ably withdrawn via the reduced passage cross-
section of the main flow opening. In the
illustrated embodiment, the tongues 21 and 22 cover
somewhat less than half oE the width of the main
flow opening 15, so that the passage cross-section
is reduced by abou-t ~0%.
If the control plate 30 is shifted further out
of the position shown in Fig. ~ in the direction of
the arrow P, the gulde pln 27 of the middle slide
mechanism 25 enter~ a first inclined portion 29',
which connects the horlzontal upper end portion 29a
with a horizontal intermediate portion 29c in the
vertical d:Lreation. The intermediate por-tion 29c
is lower than the upper end portion 29a by the
distance v/2. Whereas during the ad~ustment
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movement of the con-trol plate 30 in the dlrection
of ~he arrow P, the pin ~7 is conveyed via the
inclined portion 29' into ths intermediate portion
29c, the pin 26 of the side slide mechanism 20 is
disposed in the lower horizontal end portion 28b,
which Eixes the closed position of the side slide
mechanism 20.
The half closed position of the middla slide
mechanism 25 illustrated in ~ig. 5 results when the
pin 27 of the middle slide mechanism 25 is
positioned in the intermediate portion 29c. The
downward stroke or travel of the middle slide
mechanism 25 corresponds to the amount v/2. The
central portion 18 of the main flow opening 15 is
reduced to half of the passage height. The intake
air stream as well as the speed of -the brush roller
are further reduced. In this half open position of
the middle slide mechanism 25 illustrated in Fig.
5, the secondary flow openlng 38 (Fig. 1) is
partially opened, so that ln addition to the
minimal intake air stream for driving the air
turbine lO via the flow channel 16, a secondary air
flow is built up via the intake opening 39, the
secondary flow opening 38, and the air inlet
opening 37 for driving the air turbine lO. Thus,
the drive of the air turbine 10 that is reduced
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durlng minimal vacuum cleaning effect b~ the
minimal intake air stream is partially compensated
for in order to make an adequate tor~ue available
at the brush roller 4.
If the control plate 30 is shifted further in
the direction of the arrow ~, the guide pin 27 of
the middle slids mechanism 25 is transferred via a
further inclined portion 29" from -the in-termediate
portion 29c into the horizontal end portion 29b,
thereby carrylng out the secorld half stroke v/2.
In this position, which is illustrated in Fi~. 6,
the guide pins 26 and 27 are disposed at the back
ends of the guide slots 28 and 29, as a result of
which the main flow opening 15 is completely
closed. The intake air stream from the intake
opening 19 to the conneator 9 for carrylng off
loosened dirt particles is interrupted.
In the closed position of the middla slide
mechanism 25 of Fig. 6, the secondary ~low opening
38 is completely opened, as shown in Flg. 1, so
that via the intake opening 39, the seconclary flow
opening 38, and the air lnlet openin~ 37 an
unrestricted secondary air stream flows into the
housing 2 for driving the air turbine 10. This
ensures that even when the main flow opening 15 is
closed, a rotating drive of the brush roller 4 is
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effscted, so that Eor example a te~tile ~loor
covering or the like can be brushed to improv0 the
visual effect.
The aforementioned adjustment marks 40 on the
housing are associated with the positions o~ the
control plate 30~ Ir- the completely closed
position of the main flow opening 15 (Fig. 6), the
grip member 35 of the con-trol plate 30 is located
exactly at the mark "O". When the grip member 35
is shifted to the mark "1", the slide mechanism
arran~ement 41 assumes the position shown in Fig.
5, where the central portion 18 of the main flow
opening 15 is opened half way.
If the grip member 35 is located at the mark
"2" (Figs. 2, 4), the central portion 18 of the
main flow openlng 15 is completely opened. ~y
shifting the grip member 35 to the mark "3", the
main flow opening 15 ls then completely opened, as
shown in ~ig. 3.
As already descrlbed above, ln the posltion
"O", the secondary flow opening 38 is completely
opened, whereas whel- the sllde mechanism
arrangement 41 ls set at the mar~ "1", the
secondary flow opening is partially opened~ At the
setting "2", the secondary ~low opening 38 is
completely closed.
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Rather than carrying out the displacement of
the slid~ mechanisms in stages, i-t can also be
expedient to effect such displacement in an
infinitely variable manner. For this purpose, for
example, the end portion 29a can merge with the
lower end position 29b, which determines a closed
position, via an inclined portion that is
illustrated by dashed lines in Fi~. 6. The
important thing for the configuration of the guide
slot 2CJ i5 tha-t the one slide mechanism (for
example the middle slide mechanism 25) can be
lowered for closing o~f the flow opening only when
the other slide mechanism (for example -the side
slide mechanism 20) has at least approximately
reached its closed posltion. In particular
applications, it can be advantageous to
synchronously move both slide mechanisms or to
separately acl~ust each slide mechanism via a
suitable adjustment arrangemellt.
The present invention is, of course, in no way
restricted to the specific disclosure oi the
specifi.cation and drawings, but also encompasses
any modifications within the scope of the appended
claims.
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