Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
1247-15
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DEVICE FOR COLLECTING AND SUCKING OFF: FLUIDS
Specification
The invention relates to a device for collecting and sucking off
fluids, especially air andlor other gas with a casing at least
partially enclosing a stabilized twist flow and guiding it, device
which shows an incoming opening extending in axial direction
relative to the casing and with several suction openings which
are connected with the suction system according to the
preamble of claim 1.
An exhaust gas collecting hood according to the genus is
known from DE 42 43 $34 A1 which shows sink pipes which
penetrate radially to the casing surtace into the hood and which
show sink openings placed at their ends coaxially to the casing
surface. The sink openings take over drawing-off air in the
center of the exhaust gas collecting hood and thus spin-off a
twist flow. However, the manufacturing of sink pipes penetrating
into the hood which support sink openings orientated exactly
coaxially to the casing surface is complicated and expensive.
Moreover, it is difficult after a certain running time to free the
sink openings from dirt or impurities choking them since the sink
openings are inacessible for mechanical tools inside the casing
surface.
From DE 39 01 89b C2, we know a device for generating a -
suction flow, whereby the suction takes places cvaxially to a
casing surface and a dust hopper is provided for radially relative
to the casing surtace in direction of gravitation. Deposited dust
can be drawn off by the dust hopper over an usual lock. This
arrangement is however disadvantageous as far as the dust
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hopper has a negative influence on a stabilization of a twist flow
inside the casing surface. Moreover, the resulting operation
requires much personnel and is thus expensive since the dust
hopper has to be emptied at regular intervals. Furthermore,
when emptying the dust hopper, an operating person is subject
to materials which are eventually detrimental to health, which is
not desired nowadays in times of increased sensibilization for
protection of labour.
The WO 88!09227 described a suction hood which is swivelling
around several axles. This suction hood functions with a
turbulent flow driven by a blast stream in a casing element. This
supplementary blast stream is however expensive. Moreover, a
window is indeed provided for in the casing element but a
collecting element is used in this window, collecting element
which sucks off inside the casing element on both sides in axial
direction and which deflects the drawing off air at right angles to
the casing element and to the turbulent flow generated therein.
The aim of this invention is to make available a device of the
above mentioned type which eliminates the above mentioned
disadvantages and which achieves an improved suction with a
simple construction.
This aim is reached by a device of the above mentioned type
with the characteristics indicated in claim 1.
For this purpose, the invention provides for that the suction
openings are placed tangentially to the twist flow, whereby each
suction opening is connected with the .suction system over a
suction conduit.
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This offers the advantage that a tangential suction is available,
whereby heavier floating particles are preferably and quickly
sucked off in the sucked fluid, since these particles flow to the
outside in direction of the casing surface because of centrifugal
forces in the twist flow.
Here it is essential that it appeared surprisingly that the casing
surface has not to be configured as a continausly bent surface
but that is can also be configured as a body with a section with
one angle or with a polygonal section. Therefore, the casing
surtace can also be made through a wall andlor a ceiling
surtace of a building, especially In relation with a stepped
section, for example with a shade, a lintel, a frame or the like
without leaving the configuration according to the invention or
without the effect according to the invention being impaired.
Preferable further developments of the device are described in
the claims 2 to 11.
Thus there results a particularly simple and effective
arrangement if the one suction opening which at least exists is
configured in the casing and if the suction conduit or the suction
conduits are canfgured so that their longitudinal axis is
orientated in the area of the suction opening tangentially andlor
radially to the twist flow or to the casing. Hereby the suction
conduits have a round or a polygonal cross section, particularly
have a rectangular cross section.
A stabilized axial guiding of the twist flow inside the casing is
obtained by the fact that at least one separating element is
placed adjacent to each suction opening parallel to the twist
flow so that an axial division of the volume inside the casing is
configured over a predetermined cross section surface which is
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smaller than the whole crass section surface of the casing. In
an appropriate way, the predetermined cross section surface is
smaller than half the crass section surface of the casing and
the separating elements are particularly advantageously placed
so that a free side thereof constitutes an extension of a wall of
the incoming opening into the volume inside the casing.
In a preferred embodiment, a unique suction conduit is
configured overlapping the whole axial length of the casing and
all suction openings, whereby the suction conduit has a cross-
seCtion which is preferably enlarged funnel-shaped away from
the suction openings.
The casing is configured for example 'as a half shell which
further simples eventually necessary maintenance and
cleaning operations of the suction openings as well as the
assembly of the device itself.
In an appropriate way the casing is closed at its axial ends with
side walls.
The invention will be explained in detail below with reference to
the attached drawings.
Fig. 1 shows a first preferred embodiment of a device according
to the invention in a perspective view.
Fig. 2 shows the first embodiment of the device in a cross
section.
Fig. 3 shows the first embodiment of the device in a longitudinal
section.
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Fig. 4 shows a second preferred embodiment of a device
according to the invention in a perspective view,
Fig. 5 shows the second embodiment of the device in a cross
section.
Fig. 6 shows the second embodiment of the device in a
longitudinal section.
Fig. 7 shows a. third preferred embodiment of a device
according to the invention in a perspective view.
Fig. 8 shows the third embodiment of the device in a cross
section.
Fig. 9 shows the third embodiment of the device in a
longitudinal section.
Fig. 10 shows a fourth preferred embodiment of .a device
according to the invention in a perspective view.
Fig. 11 shows the fourth embodiment of the device in a cross
section.
Fig. 12 shows the fourfh embodinient of the device in a
longitudinal section.
Fig. 13 shows the fourth embodiment of the device in a section
along the line A-A of fig. 11.
The first preferred embodiment of a device according to the
invention 100 for collecting and sucking off fluids which Is
represented in the figures 1 to 3 comprises a casing 10 which is
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substantially partially cylindrical with an incoming conduit 12
and suction openings 14. The suction openings 14 are made in
the casing 10. A suction conduit 1B which connects the
respective suction opening 14 with a non represented suction
system corresponds to each suction conduit 14. An upper area
of the inner volume of the casing 10 in the figure is separated in
axial direction by separating elements 18 so that an axial
guiding of a twist flow stabilized in the casing 10 is realized in
this upper area, The separating elements 18 are placed
adjacent to the suction openings 14. The casing is closed by
side walls 20 at axial ends of the casing 10. The suction
conduits are configured with a round cross section and are
orientated radially to the casing 10. The tangential arrangement
of the suction opening to the twist flow is preferably obtained by
the fact that the suction conduit 16 is also extended with a small
part through the casing surface into the casing which encloses
the twist flow, whereby this part may not extend up to the
middle axis of the casing or up to the middle of the twist flow.
As can be especially seen in fig. 2, a free edge of the
separating elements 18 canstitutes an extension of one side of
the incoming conduit 12.
An ambient fluid, such as for example air loaded with
contaminants, flaws over the incoming conduit 12 constituting
an incoming opening in the casing 10 into the inner volume of
the casing 10 and generates the twist flow which substantially
follows a casing surface of the casing 10. Fluid is then removed
by the suction openings 14 and the suction conduits 16 from
this twist flow tangentially at the extreme tangential edge of the
twist flow, namely on the casing surface and is led far example
to a cleaning or filtering process in the suction system or is
simply only transported off the place of the device according to
the invention 100. Since the suction takes place tangentially,
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preferably heavier floating particles are drawn off and flow or
are pushed in flow direction to the outside in direction of the
casing surface because of occuring centrifugal forces or
centripetal forces.
It appeared in a surprising unpredictable wey that a twist flow
can also be stabilized by means of the tangential suction
openings inside the casing 1D.
The second preferred embodiment of a device according to the
invention 200 according to fig. 4 to 6 substantially corresponds
to parts of the first embodiment 1DD with the same references
so that reference is made to the description above of fig. 1 to 3.
Unlike the first preferred embodiment 1D0 the second preferred
embodiment 2D0 shows suction conduits 16 with a square
angled section.
The third preferred embodiment of a device according to the
invention 300 according to fig. 7 to 9 substantially corresponds
to parts of the first embodiment 100 with the same references
so that reference is made to the description above of fig. 1 to 3.
Unlike the first and the second preferred embodiment 100 or
Z00, the third preferred embodiment 300 show$ suction
conduits 16 orientated tangentially to the casing 10 or to the
twist flow and the suction openings 14 are placed in the casing
10 opposite the incoming conduit 12.
The fourth preferred embodiment of a device according to the
invention 400 for sucking off fluids represented in the fig. 10 to
13 comprises a casing 10 configured as a cylindric half shell at
one end of which a recess 22 constitutes respective suction
openings 14. An unique suction conduit 16 which covers all
suction openings 14 is placed over the whole axial length of the
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casing 10. The suction opening 16 enlarges with a funnei-
shaped cross section away from the suction openings 1 g.
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LIST OF REFERENCE NUMERALS
100, 200, 34D, Device for collecting and
400 sucking off
fluids
1 ~ Casing
12 Incoming conduit
14 Suction openings
16 Suction conduit
1$ Separating elements
20 ~ Side walls
22 Recess
