U.S. patent application number 15/481625 was filed with the patent office on 2017-07-27 for device for removing wet paint overspray.
The applicant listed for this patent is Durr Systems, Inc.. Invention is credited to Alexander Rajtschan, Klaus Rundel, Wolfgang Tobisch, DIETMAR WIELAND.
Application Number | 20170209891 15/481625 |
Document ID | / |
Family ID | 36549221 |
Filed Date | 2017-07-27 |
United States Patent
Application |
20170209891 |
Kind Code |
A1 |
WIELAND; DIETMAR ; et
al. |
July 27, 2017 |
DEVICE FOR REMOVING WET PAINT OVERSPRAY
Abstract
The invention relates to a device for removing wet paint
overspray from an outgoing air flow (120) containing over-spray
particles. The device separates wet paint over-spray from an
over-spray particle contained in an exhaust air stream (120). The
overspray particles in the exhaust air stream (120) are formed
during the painting at an application area (108) of a painting
installation (100). The device (126) comprises of at least one
separation apparatus for separating the over-spray from the exhaust
air stream (120). The separation apparatus includes a regeneratable
surface filter (146) and the flow path of the exhaust air stream
(120) from the application area (108) to a separating device (145)
having at least one narrowed area (146). The central direction of
flow of the exhaust air stream (120) remains essentially preserved
in passing by the narrowed area (140).
Inventors: |
WIELAND; DIETMAR;
(Waiblingen, DE) ; Tobisch; Wolfgang; (Stuttgard,
DE) ; Rundel; Klaus; (Esslingen, DE) ;
Rajtschan; Alexander; (Stuttgart, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Durr Systems, Inc. |
Southfield |
MI |
US |
|
|
Family ID: |
36549221 |
Appl. No.: |
15/481625 |
Filed: |
April 7, 2017 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11886764 |
Jan 23, 2009 |
9643118 |
|
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PCT/EP2006/002469 |
Mar 17, 2006 |
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15481625 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B05B 14/435 20180201;
B01D 46/002 20130101; B01D 2273/12 20130101; B05B 14/46 20180201;
B01D 46/24 20130101; B01D 2267/30 20130101; B01D 46/543 20130101;
B05B 14/437 20180201; B05B 14/468 20180201; Y02P 70/10 20151101;
B01D 46/10 20130101; B01D 46/521 20130101; B01D 46/0043 20130101;
B01D 46/0068 20130101; B05B 14/43 20180201; B05B 14/469
20180201 |
International
Class: |
B05B 15/12 20060101
B05B015/12; B01D 46/52 20060101 B01D046/52; B01D 46/54 20060101
B01D046/54; B01D 46/24 20060101 B01D046/24; B01D 46/00 20060101
B01D046/00 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 24, 2005 |
DE |
10 2005 013 711.3 |
Claims
1-30. (canceled)
31. Installation for painting objects, in particular vehicle
bodies, comprising at least one painting booth and at least one
device for separating wet paint over-spray from an over-spray
particle-containing exhaust air stream, wherein the overspray
particles pass into the exhaust air stream in an application area
of the painting installation; wherein the device for separating wet
paint over-spray from the exhaust air stream comprises at least one
separation device for separating the over-spray from at least a
part of the exhaust air stream, which has at least one filter
element, wherein the flow path of the exhaust air stream from the
application area to the separation device has at least one narrowed
area, wherein the device for separating wet paint over-spray from
the exhaust air stream includes at least one pre-coat supply device
which is disposed at the narrowed area of the flow path of the
exhaust air stream and delivers a pre-coat material into the
exhaust air stream, and wherein at least one filter element has a
barrier layer including the pre coat material, which prevents
agglutination of a filter surface.
32. Installation according to claim 31, wherein the narrowed area
is disposed beneath the application area.
33. Installation according to claim 31, wherein the painting booth
has a longitudinal direction, and wherein the narrowed area extends
in the longitudinal direction of the painting booth over
substantially the entire length of the painting booth.
34. Installation according to claim 31, wherein the painting booth
has a longitudinal direction, and wherein the narrowed area is
divided in the longitudinal direction of the painting booth into a
plurality of narrowed sub-areas.
35. Installation according to claim 31, wherein the painting booth
has a longitudinal direction, and wherein the narrowed area is not
sub-divided in the longitudinal direction of the painting
booth.
36. Installation according to claim 31, wherein the painting booth
has a transverse direction, and wherein the narrowed area is
divided into a plurality of narrowed sub-areas in the transverse
direction of the painting booth.
37. Installation according to claim 31, wherein the painting booth
has a transverse direction, and wherein the narrowed area is not
sub-divided in the transverse direction of the painting booth.
38. Installation according to claim 31, wherein the entrance of the
exhaust air stream into the narrowed area is disposed above the at
least one filter element.
39. Installation according to claim 31, wherein the device for
separating wet paint over-spray from the exhaust air stream
includes at least one flow guidance element, which directs at least
a portion of the exhaust air stream to the narrowed area.
40. Installation according to claim 39, wherein the flow guidance
element exhibits at least one flow guidance surface which is, at
least in a section thereof, substantially horizontally aligned.
41. Installation according to claim 39, wherein the flow guidance
element exhibits at least one flow guidance surface which is, at
least in a section thereof, inclined against the horizontal.
42. Installation according to claim 31, wherein the device for
separating wet paint over-spray from the exhaust air stream has a
base, which limits the flow path of the exhaust air stream
downwards, and wherein at least a part of the base is covered by an
area separated from an area of the device for separating wet paint
over-spray from the exhaust air stream flowed-through by the
exhaust air stream.
43. Installation according to claim 42, wherein the device for
separating wet paint over-spray from the exhaust air stream
includes a top boundary wall of the area separated from the area of
the device for separating wet paint over-spray from the exhaust air
stream flowed-through by the exhaust air stream, which top boundary
wall forms at least a part of a flow guidance element, which
directs at least a part of the exhaust air stream to the narrowed
area.
44. Installation according to claim 31, wherein the supply of the
pre-coat material into the exhaust air stream takes place
continuously.
45. Installation according to claim 31, wherein the supply of the
pre-coat material into the exhaust air stream takes place in
intervals.
46. Installation according to claim 31, wherein the at least one
filter element is capable of being cleaned in intervals.
47. Installation according to claim 31, wherein the at least one
filter element exhibits a moist surface in the operation of the
device for separating wet paint over-spray from the exhaust air
stream.
48. Installation according to claim 47, wherein a surface of the at
least one filter element is capable of being rinsed-off
continuously or in intervals.
49. Installation according to claim 31, wherein the at least one
filter element is capable of being cleaned by compressed air
pulses.
50. Installation according to claim 31, wherein the device for
separating wet paint over-spray from the exhaust air stream
contains an air circulation circuit, in which the exhaust air
stream, from which the wet paint over-spray has been separated, is
at least partially supplied to the application area again.
51. Installation according to claim 31, wherein the installation
comprises a collection belt for receiving pre-coat material and wet
paint over-spray from a plurality of filter elements and for
transporting the pre-coat material and the wet paint over-spray
along a conveying direction of the objects to be painted.
52. Installation according to claim 31, wherein the passage
cross-section at the narrowed area is so small that turbulences
appear in the exhaust air stream, which distribute the pre-coat
material in the exhaust air stream.
53. Installation according to claim 31, wherein the pre-coat
material comprises lime, an aluminum silicate, an aluminum oxide, a
silicon oxide or coating powder.
Description
PRIOR APPLICATIONS
[0001] The present application is a continuation of U.S. patent
application Ser. No. 11/886,764 filed on Jan. 23, 2009, which is a
National Stage of, and claims priority to and all advantages of
International Patent Application No. PCT/EP2006/002469 filed Mar.
17, 2006, on the basis of German Patent Application No.
DE10/2005/013711.3 filed on Mar. 24, 2005.
TECHNICAL FIELD
[0002] The present invention relates to a device for removing wet
paint overspray from an exhaust air flow containing over-spray
particles, whereby the over-spray particles in the exhaust air flow
reach into an application area of a painting installation.
TECHNICAL BACKGROUND
[0003] Such devices are used in plants for painting work parts, in
particular for spray-painting vehicle bodies, in which an air flow
is produced by an application area of the plant, which exhausts
excess wet paint from the application area.
[0004] It is well-known to separate out the carried wet paint
over-spray of a washing plant from the exhaust air flow by means of
a washing liquid.
[0005] Known washing plants have the disadvantage, however, in
particular with air circulation control, in that a high amount of
moisture is supplied to the exhaust air flow from which the wet
paint over-spray is separated, so that the exhaust air flow
resulting after separation of the wet paint over-spray must be
subjected to a energy-intensive dehumidification.
[0006] Furthermore, greater expense is required for the treatment
of the washing liquid loaded with the wet paint over-spray.
[0007] The basic object of the present invention is to provide a
device of the aforementioned type which enables a separation of the
wet paint over-spray from the exhaust air flow in a simple,
reliable and energy-saving way.
[0008] This problem is solved according to the invention with a
device having the characteristics of the generic terms of claim 1,
in that the device comprises at least one separation apparatus for
separating the over-spray from at least one part of the exhaust air
flow, which has at least one regeneratable surface filter, and that
the flow path of the exhaust air flow from the application area to
the separating apparatus comprises at least one narrowed area,
whereby the central direction of flow of the exhaust air flow
remains essentially preserved in passing the narrowed area.
[0009] A regeneratable filter is understood to be one which has a
filter surface upon which the wet paint over-spray carried by the
exhaust air flow is separated-off, and that, preferably during the
operating process of the device, is cleanable from the
separated-off paint over-spray thereon.
[0010] Such a regeneratable surface filter is a "dry" separation
device in which no liquid is used for washing the over-spray
particles out of the exhaust flow, but instead filter elements are
used for separation of the over-spray particles from the air
flow.
[0011] Thereby, cleaning of the regeneratable surface filter by
means of a "dry" separation device can take place, that is, without
using a cleaning fluid or a "wet" cleaning device which utilizes a
liquid.
[0012] A "dry" separation device can also be provided with "wet"
cleaning apparatus, as long as the deposition of the over-spray
particles on the regeneratable separation element takes place in a
dry manner, that is.
[0013] A "dry" separation device can also be provided with a "wet"
cleaning device, as long as the deposition of the over-spray
particles on the regeneratable separation element takes place in a
dry manner, that is, without washing using a washing fluid.
[0014] Preferably the entire separation of wet paint over-spray
from the exhaust air flow containing the over-spray particles takes
place completely dry, that is, without use of a fluid for washing
the over-spray particles out of the exhaust air flow.
[0015] Use of a regeneratable surface filter in the separation
device circumvents the necessity of providing a washing station and
the associated water treatment. Thereby, the energy-consumption of
the separation device and (owing to the omission of the water
treatment) also the space-requirements of the device are
significantly reduced.
[0016] The capacity to be cleaned of the surface filter also
further ensures a long service life of the filter with large
quantities of resulting wet paint over-spray.
[0017] In view of the provision of a narrowed range in the exhaust
air flow path from the application area to the separation device,
it is furthermore achieved that the regeneratable surface filter is
protected against direct effects from the application area.
[0018] Thereby, that the central flow direction of the exhaust air
flow in passing the narrowed area remains essentially preserved, it
is achieved that a premature deposition of wet paint over-spray on
the boundary walls of the narrowed area is avoided.
[0019] In a preferred arrangement of the device according to the
invention, the narrowed area is located beneath the application
area.
[0020] If the application area is arranged in a painting booth,
then the narrowed area is preferably disposed within a vertical
projection of the basal area of the painting booth.
[0021] To prevent the wet paint over-spray from the exhaust air
flow from already settling on the boundary walls of the narrowed
area, it is an advantage if the elongation of the narrowed area in
the flow direction of the exhaust air flow is shorter than approx.
6 m, preferably shorter than approx. 1 m, in particular shorter
than approx. 0.5 m.
[0022] If the application area is arranged in a painting booth with
a longitudinal direction, then the narrowed area preferably extends
in the longitudinal direction of the painting booth over
essentially the entire length of the painting booth.
[0023] Thereby the narrowed area in the longitudinal direction of
the painting booth can be divided into several narrowed
sub-areas.
[0024] Alternatively, it can also be provided that the narrowed
area in the longitudinal direction of the painting booth is not
divided.
[0025] If the application area is disposed in a painting booth with
a transverse direction, it can be provided that the narrowed area
in the transverse direction of the painting booth is divided into
several narrowed sub-areas.
[0026] Alternatively, it can also be provided that the narrowed
area in the transverse direction of the painting booth is not
divided.
[0027] The entrance of the exhaust air flow into the narrowed area
is preferably arranged above the at least one regeneratable surface
filter.
[0028] If the application area is disposed in a painting booth with
a transverse direction, then the smallest cross-section of the
narrowed area flowed through by the exhaust air stream preferably
has an extension in the transverse direction of the painting booth,
which amounts to at most approx. 20% of the extension of the
painting booth in the transverse direction of the painting
booth.
[0029] In order for the at least one regeneratable surface filter
to be protected against damages, it is advantageous if at least one
shielding element is arranged vertically over the at least one
regeneratable surface filter, which will prevent a vertical falling
down of articles, dirt and/or paint particles from the application
area upon the regeneratable surface filter.
[0030] Thereby it may be provided that the at least one shielding
element forms the boundary of the narrowed area.
[0031] In order for favorable flow conditions in the exhaust air
flow path to be obtained, it is desirable if the device contain at
least one flow-guidance element, which directs at least one portion
of the exhaust stream to the narrowed area.
[0032] Thereby the flow guidance element can feature an at least in
sections, essentially horizontally aligned flow guidance
surface.
[0033] Alternatively, it may also be provided that the flow
guidance element features a flow guidance element inclined at least
in sections against the horizontal, preferably towards the narrowed
area.
[0034] If the device has a bottom, which limits the exhaust air
flow path downward, it can be provided that at least one part of
the bottom is covered by an area separated from the area of the
device flowed through by the exhaust air. In this way the bottom
surface area is reduced, which is contaminated by wet paint
over-spray separating out of the exhaust air flow before reaching
the at least one surface filter. Thereby, it can be provided that
an upper boundary wall of the area separated from the area of the
device flowed through by the exhaust air flow forms at least one
part of a flow guidance element, which directs at least one portion
of the exhaust air flow to the narrowed area.
[0035] If the application area is arranged in a painting booth and
the device comprises at least one exhaust air duct, into which at
least one portion of the exhaust air flow enters after passing the
separation device, then a special space-saving structure of the
device is achieved, if the exhaust air channel is disposed within a
vertical projection of the basal surface of the painting booth.
[0036] In order to facilitate the cleaning of the regeneratable
surface filter, it is advantageous, if the at least one exhaust air
channel exhibits a barrier layer comprising a pre-coat material
which prevents agglutination of the filter surface.
[0037] For the barrier layer made of precoat-material to fabricate
on the surface filter, it can be provided that the device comprises
at least one pre-coat feeding apparatus, which delivers a pre-coat
material in the exhaust air flow.
[0038] Thereby, the supply of pre-coat material in the exhaust air
flow can take place continuously or in intervals.
[0039] As pre-coat materials, lime, aluminum silicates, aluminas,
silicon oxides, powder coatings or the like are taken into
consideration.
[0040] In principle, any medium is suitable as a pre-coat material
which has the capacity to absorb the liquid portion of the wet
paint over-spray.
[0041] Moreover it is possible, to arrange the at least one
pre-coat feeding apparatus in direct connection to the application
area, for example on the bottom area of the painting booth.
[0042] But it is particularly advantageous if the at least one
pre-coat feeding apparatus is disposed at the narrowed area of the
exhaust air flow path. In the narrowed area of the exhaust air flow
path high flow velocities control, so that by the feeding of the
pre-coat material to this location a particularly good pre-coat
distribution is obtained by means of venturi turbulence.
[0043] With pre-coating there is the possibility of interim
pre-coating, whereby a new pre-coating material is applied without
prior cleaning of the surface filter, so that the later cleaning
characteristics of the surface filter are improved.
[0044] The at least one regeneratable surface filter of the
separation device is preferably capable of being cleaned in
intervals.
[0045] Alternatively or additionally it can thereby be provided
that the at least one regeneratable surface filter exhibits a moist
surface in the operation of the device.
[0046] The surface filter can be kept damp, for example, by use of
rinsing- or humidification media such as demineralized water,
butylglycol or other solvents, in order to facilitate the cleaning
of the surface filter.
[0047] These humidification media can be introduced at the same
locations in the exhaust air stream as the previously described
pre-coat materials.
[0048] For a basic cleaning of the filter surface of the surface
filter it is advantageous, if the surface of the at least one
regeneratable surface filter is capable of being rinsed off
continuously or in intervals.
[0049] Alternatively or additionally it can thereby be provided
that the at least one regeneratable surface filter is capable of
being cleaned by compressed air impulses.
[0050] A particularly energy-saving operation of the painting
installation is possible, if the device has an air circulation
cycle, in which the exhaust air flow, from which the wet paint
over-spray has been separated, is at least partially re-delivered
to the application area.
[0051] Claim 30 directed to an installation for the painting of
objects, particularly of vehicle bodies, which comprises at least
one painting booth and at least one device according to the
invention for separating wet paint over-spray from an over-spray
particle-containing exhaust air stream.
[0052] Further characteristics and advantages are the subject of
the following description and graphic illustration of exemplary
embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0053] Other advantages of the present invention will be readily
appreciated as the same becomes better understood by reference to
the following detailed description when considered in connection
with the accompanying drawings wherein:
[0054] FIG. 1 a schematic vertical cross-section through a first
embodiment of a painting booth with a device arranged under it for
separating wet paint over-spray from an over-spray
particle-containing exhaust air stream, which includes two
separation devices for separating the over-spray from the exhaust
air stream and also two exhaust ducts, which run laterally to the
left and/or right alongside the floor plan of the painting booth,
whereby a narrowed area of the flow path of the exhaust air stream
is provided between an application area of the painting booth and
the separation devices, which is bounded by horizontally aligned
flow guidance elements;
[0055] FIG. 2 a schematic side view of the installation of FIG.
1;
[0056] FIG. 3 a schematic top view from above of the installation
of FIGS. 1 and 2;
[0057] FIG. 4 a schematic representation in perspective of the
installation of FIG. 1 to FIG. 3;
[0058] FIG. 5 a schematic representation of an air circulation
cycle of the installation of FIGS. 1 to 4;
[0059] FIG. 6 a schematic representation in perspective of a
regeneratable surface filter of the installation of FIG. 1-FIG.
5;
[0060] FIG. 7 a schematic longitudinal section through the surface
filter of FIG. 6, which illustrates a cleaning process of the
surface filter;
[0061] FIG. 8 a schematic representation in perspective of an
alternative embodiment of a regeneratable surface filter;
[0062] FIG. 9 a schematic cross-section through the surface filter
of FIG. 8, which illustrates a cleaning process of the surface
filter;
[0063] FIG. 10 a schematic top view from above the surface filter
of FIGS. 8 and 9;
[0064] FIG. 11 a schematic cross-section through a second
embodiment of a painting booth with a device arranged under it for
separating wet paint over-spray from an exhaust air stream
containing over-spray particles, which includes two separation
devices for separating the over-spray from the exhaust air stream
and also two exhaust ducts, which run laterally to the left and/or
right alongside the floor plan of the painting booth, whereby a
narrowed area of the flow path of the exhaust air stream is
provided between an application area of the painting booth and the
separation devices, which is bounded by flow guidance elements
which are inclined against the horizontal;
[0065] FIG. 12 a schematic side view of the installation of FIG.
11;
[0066] FIG. 13 a schematic top view from above of the installation
of FIGS. 11 and 12;
[0067] FIG. 14 a schematic representation in perspective of the
installation of FIG. 11 to FIG. 13;
[0068] FIG. 15 a schematic cross-section through a third embodiment
of a painting booth with a device arranged under it for separating
wet paint over-spray from an exhaust air stream containing
over-spray particles, which includes two separation devices for
separating the over-spray from the exhaust air stream and also two
exhaust ducts, which run laterally to the left and/or right
alongside the floor plan of the painting booth, whereby between an
application area of the painting booth and the separation devices a
narrowed area of the flow path of the exhaust air stream is
provided in the form of a shaft extending in a vertical
direction;
[0069] FIG. 16 a schematic side view of the installation of FIG.
15;
[0070] FIG. 17 a schematic top view from above of the installation
of FIGS. 15 and 16;
[0071] FIG. 18 a schematic representation in perspective of the
installation of FIG. 15 to FIG. 17;
[0072] FIG. 19 a schematic cross-section through a fourth
embodiment of a painting booth with a device arranged under it for
separating wet paint over-spray from an exhaust air stream
containing over-spray particles, which includes a separation device
for separating the over-spray from the exhaust air stream and an
exhaust duct arranged within a vertical projection of the basal
surface of the painting booth;
[0073] FIG. 20 a schematic side view of the installation of FIG.
19;
[0074] FIG. 21 a schematic top view from above of the installation
of FIG. 19 and FIG. 20; and
[0075] FIG. 22 a schematic representation in perspective of the
installation of FIGS. 19 to 21.
[0076] Equal or functionally equivalent elements are designated in
the figures with the same reference symbols.
DETAILED DESCRIPTION
[0077] An installation shown in FIGS. 1 to 7, marked 100 as a whole
for the spray-coating of vehicle bodies 102 which includes a
clearly schematically represented conveyer device 104, by means of
which the vehicle bodies 102 can be moved along in a conveying
direction 106 through an application area 108 of a painting booth
marked 110 as a whole.
[0078] The conveying device 104 can, by way of example, be
constructed as an inverted circular conveyer or as an inverted
monorail conveyer.
[0079] In particular the conveyer device 104 can be formed in two
parts and--as best understood from FIGS. 1, 3 and 4--includes two
conveyer belts 104a and 104b extending parallel to the conveyer
106, which are spaced apart from one another in a horizontal
direction perpendicular to the conveyer 106.
[0080] The application area 108 is the interior chamber of painting
booth 110, which perpendicular of it to the conveyer 106, which
corresponds to the longitudinal direction of the painting booth
110, it is limited, respectively, by a booth wall 114 running in
horizontal transverse direction 112 on both sides of the conveyer
device 104.
[0081] On both sides of the conveyer device 104 spray-painting
devices 116 (see FIGS. 1-4) are arranged in the painting booth 110,
for example, in the form of paint application robots.
[0082] By means of a compressed air production device 118
schematically represented in FIG. 5 an air stream is produced which
essentially pervades the application area vertically from top to
bottom, as indicated by the arrow 119 in FIG. 1.
[0083] This air stream takes up paint over-spray in the form of
over-spray particles in the application area 108.
[0084] The term "particle" includes solid as well as liquid
components, particularly drops.
[0085] A wet paint is used for coating in the installation 100,
thus the wet paint over-spray consists of paint drops.
[0086] Most of the over-spray particles have a largest size of in a
range from approx. 1 gm to approx. 100 pm.
[0087] The exhaust air flow designated by the arrow 120 leaves the
painting booth 110 through a booth bottom 122, which contains an
air-permeable lattice grate 124.
[0088] The installation 100 also includes a device marked 126 as a
whole, for separating wet paint over-spray from the air flow 120,
which is arranged beneath the application area 108.
[0089] The device 126 includes an essentially quadrangular-shaped
flow chamber 128, which reaches over into the conveyer 106 over the
whole length of the painting booth 110 and is bounded in the
transverse direction 112 of the painting booth 110 by vertical
side-walls 130, which align essentially with the lateral
booth-walls 114 of the painting booth 110, so that the flow chamber
128 has essentially the same horizontal cross-sectional area as the
painting booth 110 and is arranged essentially completely within
the vertical projection of the basal surface of the painting booth
110.
[0090] The flow chamber 128 is subdivided by flow guidance elements
132, which in this exemplary embodiment are formed as essentially
horizontal flow guidance plates 134, into an upper section 136 and
a lower section 138.
[0091] The upper section 136 and lower section 138 of the flow
chamber 128 are connected to each other by a narrowed area 140,
which is in the form of a space 142 between the free borders
opposite to each other of the flow guidance elements 132 and which
forms a narrowing in the flow path of the exhaust air stream 120
through the flow chamber 128.
[0092] The upper sides of the flow guidance elements 132 form in
each case a flow guidance surface 135, which directs the exhaust
air stream to the narrowed area 140.
[0093] A pre-coat feed device 144 is arranged at the narrowed area
140 of the flow path, which continuously or interval-wise supplies
a pre-coat material into the exhaust air stream 120.
[0094] The pre-coat feed device 144 can, for example, be designed
as a pre-coat spray nozzle, which supplies the pre-coat material in
the form of a spray mist into the exhaust air stream 120.
[0095] The arrangement of the pre-coat feed device 144 at the
narrowed area 140 of the exhaust air stream 120 offers the
advantage, that there due to the elevated flow velocity of the
exhaust air stream 120 and because of the small passage
cross-section, turbulences appear in the exhaust air stream, which
make possible a swirling of the pre-coat material in the exhaust
air stream 120 and consequent particularly good distribution of the
pre-coat material in the exhaust air stream 120.
[0096] The pre-coat supply device 144 is attached to a (not shown)
pre-coat feed pipe which feeds the pre-coat material in flowable
condition via a (not shown) pre-coat feed pump from a (not shown)
pre-coat storage container.
[0097] In principle, any medium is suitable as a pre-coat material
which has the capacity to absorb the liquid portion of the wet
paint over-spray.
[0098] For example, as pre-coat materials, lime, aluminum
silicates, aluminas, silicon oxides, powder coatings or the like
are taken into consideration.
[0099] In order to make the pre-coat material flowable and
sprayable, i.e. aqueous dispersions of the aforementioned materials
are used.
[0100] If the filter sequential to the pre-coat feed device 144 is
not to be pre-coated, but should only be moisturized, then also
only a moisturizing medium can be introduced into the exhaust air
stream 120 by means of the pre-coat feed device 144.
[0101] As such, moisturizing media in particular i.e.,
demineralized water, butylglycol or other solvents are taken into
consideration.
[0102] A separation device 145 for separating wet paint over-spray
from the exhaust air stream 120 is provided in the lower section
138 of the flow chamber 128 on both sides, respectively, of the
narrowed area 140. The separation devices 145 include several
regeneratable surface filters 146, spaced apart from each other on
the conveyer 106, arranged, respectively, opposite to one another
on both sides of the vertical side-walls 130 of the flow chamber
128, which with their filter elements 148 extend into the lower
section 138 of the flow chamber 128 (see in particular FIGS. 1, 2
and 4).
[0103] This regeneratable surface filter 146 is shown in detail in
FIGS. 6 and 7.
[0104] Each of the regeneratable surface filters 146 contains a
hollow fundamental body 150, to which several, for example, four
filter elements 154 are attached.
[0105] Filter elements 154 are, for example, are formed essentially
in a plate shape and preferably feature, as is seen from FIG. 6, a
serrated cross-section, in order for the available filter surface
156 to be enlarged.
[0106] The filter elements 154 can be formed, for example, as
plates made from sintered polyethylene, which are provided with a
polytetrafluoroethylene (PTFE) membrane on their outer surface.
[0107] Alternatively or additionally, it can also be provided that
the filter elements 154 are made of a non-woven fabric with a PTFE
coating.
[0108] For this reason, the PTFE coating serves, as the case may
be, to raise the filter quality of the surface filter 146 (that is,
to diminish its' permeability) and also to prevent the permanent
adhesion of the wet paint over-spray deposited from the exhaust air
stream 120.
[0109] Both the base material of the filter element 154 and its'
PTFE-coating exhibit a porosity, so that the exhaust air can pass
through the pores into the interior space 176 of the respective
filter element 154.
[0110] To prevent the agglutination of the filter surface 156, it
is further provided with a barrier layer formed from the pre-coat
material supplied in the exhaust air stream 120.
[0111] This barrier layer easily forms itself in the operation of
device 126 by deposition on the filter surface 156 of the pre-coat
material released in the exhaust air stream 120.
[0112] Preferably, the amount of pre-coat material released into
the exhaust air stream 120 is regulated, so that the thickness of
the barrier layer made from the pre-coat material on the filter
element 154 of the regeneratable surface filter 146 is in the range
of i.e. approx. 150 pm to 20011 m.
[0113] The exhaust air stream 120 overcoats the filter surfaces 156
of the filter element 154 of the regeneratable surface filter 146,
whereby both the carried pre-coat material and also the carried wet
paint over-spray is deposited upon the filter surfaces 156, and
passes through the porous filter surfaces 156 into the interior
space 176 of the filter element 154, which are connected with the
hollow space within the fundamental body 150.
[0114] The purified exhaust air stream 120 thus by going through
the fundamental body 150 passes, respectively, into an exhaust air
pipet 158, which leads from the respective regeneratable surface
filter 146 to an exhaust air duct 160 on the side next to a
vertical side-wall 130 of the flow chamber 128, which duct runs
parallel to conveyer 106.
[0115] As is clear from the schematic representation of FIG. 5, the
purified exhaust air from the wet paint over-spray passes out of
the two exhaust air ducts 160 at least partially back to the air
flow production device 118, which conducts the purified exhaust air
via a supply line 162 once again to the application area 108 in the
painting booth 110.
[0116] Another part of the purified exhaust air stream is delivered
via an exhaust air blower 164 in an exhaust air supply line 166 to
the surrounding area.
[0117] This part of the exhaust air stream delivered to the
surrounding area is replaced by fresh air, which is fed to the air
flow production device 118 via a fresh air supply line 168.
[0118] The main part of the air led through the application area
108 is thus guided in an air circulation cycle 170, which includes
the air production device 118, the supply line 162, the application
area 108, the flow chamber 128 and the exhaust air duct 160,
whereby a constant heating of the fresh delivered supply air is
avoided and thereby the energy costs are significantly lowered.
[0119] Since the separation of the wet paint over-spray from the
exhaust air stream 120 by means of the regeneratable surface filter
146 takes place dry, that is, without washing with a cleaning
fluid, the air guided in the air circulation cycle 170 is not
humidified in the separation of the wet paint over-spray, so that
no devices for humidification of the air guided in the air
circulation cycle 170 are necessary at all.
[0120] Furthermore, no devices are necessary for separating the wet
paint over-spray from a washout-cleaning fluid.
[0121] The regeneratable surface filter 146 is cleaned by
compressed air impulses in determined time intervals, when its'
coating by wet paint over-spray reaches a preset amount.
[0122] This cleaning can take place, i.e. one time per work shift,
that is, two or three times per work day.
[0123] The required compressed air impulse is produced by a
compressed air reservoir 172, which is arranged at the fundamental
body 150 of the respective regeneratable surface filter 146 and
thereby is in the position, to deliver compressed air impulses to a
compressed air pipe 174, which runs within the respective
fundamental body 150 and leads from the compressed air reservoir
into the interior space 176 of the filter element 154.
[0124] From the interior spaces 176 of the filter element 154 the
compressed air impulse passes through the porous filter surfaces
156 into the outer space of the filter element 154, whereby the
barrier layer formed from pre-coat material on the filter surfaces
156 and the wet paint over-spray deposited on the filter surfaces
156 are dissolved, so that the filter surfaces 156 are converted
back into their cleansed original condition.
[0125] The flow direction of the compressed air through a
regeneratable surface filter 146 during the cleaning is designated
in FIG. 7 by the arrow 177.
[0126] The compressed air reserve in the compressed air reservoir
172 is replenished by (not shown) compressed air supply lines from
an on-site compressed air network.
[0127] A cleaning by compressed air impulses can alternatively or
additionally be modified such that the regeneratable surface filter
146 is washed out by means of suitable spray device in specified
intervals, in order to remove the wet paint over-spray deposited on
the filter surfaces 156.
[0128] As is best seen from FIGS. 1 and 2, the material cleaned off
from the filter surfaces 156 of the regeneratable filter 146
arrives at a collecting belt 178 at the bottom of the flow chamber
128, which is designed, i.e. as a endless belt circulating via a
driven roller 180 and a non-driven guide roller 182.
[0129] The driven roller 180 is made to rotate by means of a drive
motor 184, in order to shift the collection belt 178 in motion
lengthwise of the conveyer 106.
[0130] In this way, via the collection belt 178 the material
deposited on the surface of the collection belt 178 from the
regeneratable surface filter 146, which includes pre-coat material
and deposited wet paint over-spray, is transported to a (not shown)
separating device, from which this material (i.e. by means of a
stripping device) is dissolved, collected and if necessary,
recycled.
[0131] The collection belt 178 also takes up a part of the wet
paint over-spray which deposits directly from the exhaust air
stream 120 onto the collection belt 178, before the exhaust air
stream 120 reaches the regeneratable surface filter 146.
[0132] An alternative development of the regeneratable surface
filter 146, which is usable in the device 126, is shown in FIGS. 8
to 10.
[0133] The regeneratable surface filter 146 includes instead of
multiple, vertically oriented plate-shaped filter elements arranged
next to one another, an essentially cylindrical filter element
154', which also contains, viewable in the cross-section, a
serrated filter surface 156 for enlargement of the available filter
surface 156.
[0134] In addition, in this embodiment for production of the
compressed air impulse, a rinsing liquid loop 186 is provided for
cleaning of the regeneratable surface filter 146, which sprays a
rinsing liquid through to the radial inner surface of the rinsing
liquid delivery port of the rinsing liquid loop 186 against the
filter surface 156 of the filter element 154', so that the rinsing
liquid dissolves the barrier layer and the wet paint over-spray
deposited on the filter surface 156 and carried on the collection
belt 178.
[0135] The second embodiment shown in FIGS. 11-14 of an
installation 100 for painting of vehicle bodies 102 is thereby
distinguished from the above-mentioned first embodiment, in that
the flow guidance elements 132, which divide the lower section 138
from the upper section 136 of the flow chamber 128 of the device
126 for separation of the wet paint over-spray, are not in this
second embodiment, in contrast to the first embodiment, aligned
essentially horizontally, but rather, as is best seen from FIG. 11,
but are inclined against the horizontal, so that they slope towards
the narrowed area 140.
[0136] The angle of inclination against the horizontal is
preferably approx. 5.degree. to approx. 30.degree..
[0137] Via this inclination of the flow guidance elements 132 and
therewith the flow line surfaces 135 at their top side, a
funnel-shaped form of the lower area of the upper section 136 of
the flow chamber 128 is obtained, through which the air stream is
comparatively measured out to the narrowed area 140 and the extent
of turbulences at the top side of the flow guidance elements is
reduced. In this way, a lesser portion of the wet paint over-spray
is already deposited on the flow line surfaces 135, before the air
stream 120 reaches the lower section 138 of the flow chamber
128.
[0138] Furthermore, the flow guidance elements 132 in the second
embodiment are set somewhat higher within the flow chamber 128 than
in the first embodiment.
[0139] Apart from that, the second embodiment shown in FIGS. 11 to
14, of an installation 100 for painting vehicle bodies 102 agrees
with respect to structure and function with the first embodiment
shown in FIGS. 1-10, insofar as its' aforementioned description is
concerned.
[0140] A third embodiment shown in FIGS. 15-18 of an installation
100 for painting vehicle bodies 102 is thereby distinguished from
the previously described second embodiment, in that the narrowed
area 140 is formed not only by a space 142 between the borders
arranged opposite to each other of the flow guidance elements 132,
but rather includes an exhaust air shaft 188 extending vertically
downwards from borders arranged opposite to each other of the flow
guidance elements 132, which is bounded on both its' side-walls by
vertical side-wall ducts 190 extending in the conveyer 106.
[0141] Between the lower border of each side-wall duct 190 and the
top side of the collection belt 178 a vertical space 192 is
respectively formed, through which the exhaust air stream exits
from the narrowed area 140 into the lower section 138 of the flow
chamber 128, whereby the lower section 138 of the flow chamber 128
in this embodiment is divided into two sub-areas 138a, 138b
arranged on the side of the exhaust air shaft 188.
[0142] Furthermore, in this embodiment the filter elements 154 of
the regeneratable surface filter 146 do not extend in essentially
horizontal direction into the lower section 138 of the flow chamber
138, but rather are inclined to a greater degree against the
horizontal, and in fact are inclined preferably at about the same
angle as the flow guidance surfaces 135 of the flow guidance
elements 132.
[0143] This angle of inclination against the horizontal is
preferably in the range from approx. 5.degree. to approx.
30.degree..
[0144] On the basis of this inclination of the filter elements 154
of the regeneratable surface filter 146 opposite to the horizontal,
the fundamental body 150 of the regeneratable surface filter 146
and the top area of the side-walls 130 of the lower section 138 of
the flow chamber 128 are also not vertically aligned, but rather
are inclined against the vertical around a sharp corner, which
corresponds to the angle of inclination of the filter elements 154
and the flow guidance surfaces 135 towards the horizontal.
[0145] In this embodiment the regeneratable surface filters 146 are
especially well protected against objects falling from the
application area 108.
[0146] Moreover, the top section 136 and the lower section 138 of
the flow chamber 128 are fluidic decoupled from each other by the
air exhaust shaft 188, so that the exhaust air stream in the lower
section 138 of the flow chamber 128 is independent to a large
extent from the flow conditions in the top section 136 of the flow
chamber 128.
[0147] Since in this embodiment two spaces 192 are present, through
which the exhaust air stream 120 enters into the lower section 138
of the flow chamber 128, two pre-coat feeding devices 144 are also
provided, which respectively are arranged adjacent to one of the
vertical spaces 192 at the lower end of one of the shaft side-walls
190.
[0148] In addition, the third embodiment shown in FIGS. 15-18 of an
installation 100 for painting of vehicle bodies 102 agrees with
respect to structure and function with the first embodiment shown
in FIGS. 11-14, insofar as its' aforementioned description is
concerned.
[0149] A fourth embodiment shown in FIGS. 19-22 of an installation
100 for painting of vehicle bodies 102 is thereby distinguished
from the previously described first embodiment, in that the device
126 for separating wet paint over-spray from the exhaust air stream
120 is not symmetrical to the longitudinal central plane 194 of the
painting booth 110, but rather is asymmetrical to this longitudinal
central plane 194.
[0150] In particular, the regeneratable filter surfaces 146 in this
embodiment are arranged only on one side of the longitudinal
central plane 194 (namely, see the side depicted on the left in
FIG. 19).
[0151] In this embodiment only a single exhaust air duct 160 is
provided, which however is not arranged on the side outside of the
side-wall 130 of the flow chamber 128, but instead is integrated
into the flow chamber 128, and is arranged directly under one of
the flow guidance elements 132, so that the affected flow guidance
element 132 forms an upper boundary of the exhaust air chamber
160.
[0152] In this embodiment, the regeneratable surface filters 146
are not connected via exhaust air pipe 158 with the exhaust air
chamber 160, but rather are arranged directly at a lower boundary
wall 196 of the exhaust air chamber 160, whereby the filter
elements 154 of the regeneratable surface filter 146 hang down in
essentially vertical direction from the lower boundary wall 196 of
the exhaust air duct 160 into the lower section 138 of the flow
chamber 128.
[0153] By this pendent arrangement, a particularly efficient
cleaning of the regeneratable surface filter 146 is obtained.
[0154] The side of the flow guidance chamber 128 lying opposite to
the side of the lower section 138 of the flow chamber 128 which is
provided with the regeneratable surface filter 146 is separated by
a vertical dividing wall 198 from the region of the lower section
138 of the flow chamber 128 which is flowed-through by the exhaust
air flow stream 120.
[0155] This separated area 200 is upwardly bordered by one of the
flow guidance elements 132 and extends downwards up to the base 202
of the flow chamber 128.
[0156] This area 200 which is separated from the flowed-through
chamber 128 can, for example, be used for the uptake of auxiliary
attachments, such as blowers, storage containers, pumps or the
like.
[0157] Alternatively or additionally, it is possible to use the
separated area 200 as an air duct, i.e. as an additional exhaust
air duct, fresh air supply duct or exhaust air discharge duct.
[0158] The flowed-through area of the lower section 138 of flow
chamber 128 is bordered downwards by the collection belt 178.
[0159] In particular it is clear from FIG. 20 that the collection
band 178 is not cleaned in the area of its' non-driven guide roller
182 via a stripping device 204 of the material collected from the
surface of the collection belt 178, which contains pre-coat
material and deposited wet pain over-spray, whereby the material
stripped-off by the collection belt 178 is deposited into a mobile
storage container 206.
[0160] If in the mobile storage container 206 a specified highest
fill level is reached, the mobile storage container 206 is
exchanged for an empty mobile storage container and the filled
mobile storage container 206 is conveyed to a (not shown)
collection and recycling station.
[0161] Since in the fourth embodiment shown in FIGS. 19-22 all
components of the device 126 for separating wet paint over-spray
are arranged within the vertical projection of the basal surface of
the painting booth 110, this embodiment is particularly compact in
construction and is specially suited for crowded space
conditions.
[0162] Moreover, the fourth embodiment shown in FIGS. 19-22 agrees
in respect to structure and function with the first embodiment
shown in FIGS. 1-10, insofar as its previous description is
concerned.
[0163] Obviously, many modifications and variations of the present
invention are possible in light of the above teachings and the
foregoing invention has been described in accordance with the
relevant legal standards; thus, the description is merely exemplary
rather than limiting in nature. Variations and modifications to the
disclosed embodiment may become apparent to those skilled in the
art and do come within the scope of the invention. Accordingly, the
scope of the legal protection afforded this invention can only be
determined by studying the following claims.
* * * * *