Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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PO~DER COl.L.EC'rION ~; YSTEM
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~I~LD OF rrHE INV~ITION
This invention relates to the field of powder
coating booths and collection systems for electrostatic
application of powder coating materials. More
particularlv, the in~ention relates to an apparatus to
quickly and easily align a powder spray canopy with a fan
plenum so that a powder collector can be quickly aligned
and effectively sealed to both the powder spray canopy
and the fan plenum. The invention also relates to an
improved filter cart idge mounting assembly which allows
for quick and easy mounting and dismounting of ~ilter
, cartridges in the powder collector.
BACRGROUND OF TXE INVEN~ION
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Powder booths for electros~atic application of
powder materials to articles typically include a spray
booth and a conveyor for carrying the article -to be
sprayed through the spray booth. Spray guns mounted in
the booth and connected to a source of air entrained
~ ~ 20 powder, such as a powder feed hopper and powder pump,
! : spray electrostatically charged powder material onto the
electrically grounded article carried by the conveyor
through the booth. An important feature of the powder
booths is th~ apparatus for ~ollecting oversprayed
;25~powder, that is the powder which doe~ not adhere to the
h~
articles being powder co~ted, and returning this powder
to the spray guns. Typically, an ~xhaust system
including a fan plen~lm assembly creates a negative
pressure i~ the booth and causes oversprayed powder to be
drawn into the powder collector where the air is
separated from the powder prior to exhausting the cleaned
air to atmosphere. The oversprayed powder is typically
collected at the bottom of the powder collector where it
is recirculated to the powder feed hopper for return to
the spray guns.
When the air carries the loose powder from within
the spray booth into the powder collector, some of the
powder falls and collects at the bottom of the collector
while the remainder collects on the outside of the one or
more filters~ This latter powder can be removed by
techniques including air pulsing, as discussed in U.S.
Patent No. 4,662,309, assigned to Nordson Corp~, the
assignee of the present invention, which patent is
incorporated in its entirety herein. I
Typically, interchangeable powder collec.toxs are
moved into or out of position under or adjacent the spray
\ booth to enable the use of a different powder collector
\ for each color powder being spr~yed. The powder
collectors have an inlet opening adapted to be aligned
with and securely sealed against a powder exhaus-t opening
in the canopy of the spray booth. An airtight seal is
important to prevent the escape of spray powder to the
surrounding atmosphere. Further, the powder collectors
have an air outlet adapted to be aligned with and sealed
against the air inlet opening of an exhaust plenum
assembly. The integrity of this seal is also very
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important to insuxe that the negative pressure developed
by the exhaust fan in the fan plenum fully acts within
the spray booth to efficiently draw all of the
oversprayed po~Jder into the powder collector. Also an
airtight seal around the opening into the air plenum is
important to pre~ent leakage of the cleaning a.ir pulses
directed from the plenum into the powder collector to
clean the filters. Such leakage would reduce the
effective of cleaning of the filters.
In setting up powder booth spray systems in the past
with free standing, independently supported fan plenums,
such as is shown in U.S. 4,498,913, the spray booth was
~ initially aligned with respect to ~he conveyor line
- extending therethrough. Typically the spray booth had a
base with six or eight legs, each having an adjustable
foot, e.g., a caster. The aligning of the spray booth
was labor intensive and time consuming particularly ~here
there were irregularities in the worX floor on which the
booth rested.
Next, the air inlet port of the exhaust fan plenum
had to be aligned with respect to the powder exhaust
opening in the spray booth canopy so that when the powder
collector was moved lnto place, its inlet opening could
be aligned with and sealed against the powder exhaust
opening i~ the canopy and its air outlet could
simultaneously be aligned with and sealed to the air
inlet opening of the exhaust plenum assembly. This
typically required time consuming, labor intensive
adjustment of the casters on the four legs supporting the
~an plenum. Finally, the casters on the four legs of the
powder collector were a.justed to properly seal the
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collector against both the booth and the air plenum.
In another type of prior ark booth, as illustrated
in U.S. Patent Nos. 4,277,260 and 4,378,728, the fan
section is structurally coupled to the spray booth. In
this case, since the fan plenum ;.s quite heavy and ii
cantilevered from the booth, the spray booth canopy has
to be constructed of heavy weight metal to support the
fan plenum. This is particularly so because in additio~
to the fan section being heavy, it also generates a great
deal of vibration, especially from the valve manifold
used to pulse clean the filter cartridges. Besides being
expensive, a spray booth canopy of heavy weight metal
construction tends to attract the powde~ coating material
which then sticks to the booth walls rather than the
article which is to be powder coated.
In U.SO Patent No. 4,354,451, the fan unit is
positionèd above the top of the spray booth and mounted
either directly to the top of the spray booth or mounted
independently of the spray booth. In both case~ the
system is deficient. First, the powder collector is very
tall and is therefore a~Xward to safely maneuver across
'~ the plant floor, especially since it is replaced whenever
a different color is sprayed. Second, the spray booth
would have to be constructed of heavy weight metal in
order to support the fan unit~
Another common problem in the prior art relates to
the apparatui used to secuxe the air filters within the
powder collector. As illustrated in prior art U.S.
4,218,277, air filters can have a central tie rod which
~; 30 lS secured to a hole through a bottom plate by a threaded
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nut. One reason why this design is deficient is that
over time the hole provides a path for unfiltered powder
to enter the clean air fan plenum. When particles of
powder escape into the clea~ air fan plenum, any
downstream filter, specifically the final filter ~hich is
designed to filter extremely small sized particles,
quickly clogs causing a shutdown of the entire powder
coating operation. Further, the filter as designed is
difficult to mount in the collector. In many instances,
the installation of this filter required two installers,
one on the exhaust side and the other on the inlet side
of the powder collector.
OBJECTS AP~D ~U~RY O~ ~E I~EN~ION
It is an object of the present invention to align a
powder spray canopy with a fan plenum so that a powder
collector can be quickly aligned and effectively sealed
to both the powder booth canopy and the fan plenum to
obviate the problems and limitations of the prior art
systems.
It is a further ~bject of the present invention to
provide an improved filter cartridge mounting assembly
which allows for quic~ and easy mounting and dismounting
of filter cartridges in the powder collector.
It is a still further object of the present
invention to provide structural components for
compression mounting vertically oriented, filter
cartridges so that they are easily installed and have a
~ simple and reliable seal.
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It is a ~et further object of the present invention
to provide an improved seal between the fan plenum a~d
the powder collector.
Yet another ob~ect is to provide an improved booth
design wherein the fan plenum i5 supported by the booth
in such a way that the booth canopy can be constructed of
lightweight, plastic material.
In accordance with the invention, there is provided
a powder coating system comprising a hase with a fan
o support secured thereto. The fan support is adapted to
support a fan plenum assembly having an inlet opening in
a bottom wàll thereof. A canopy of a powder spray booth
having an exhaust opening in a side wall is secured to
the base and to the fan support. A powder collector
` 15 having an inlet opening in a f~ont wall and an exhaust
opening in a top plate is ada~ted to be sealed against
the canopy and the fan plenum assem~ly whereby the
, exhaust opening in the side wall of the canopy seals
against the inlet opening of the powder collect~r and the
inlet opening of the fan plenum assembly seals against
the exhaust opening of the powder collector.
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Also in accordance with the invention, a leveling
~,~ means is provided on the base to simultaneously level the
fan plenum assembly and the booth canopy. A leveling
means on the powder collector simultaneously levels the
powder collector ~ith respect to the fan plenum assembly
and the canopy, whereby the inlet opening of the powder
collector is aligned for sealing to the exhaust opening
, of the canopy and the exhaust opening of the powder
collector is aligned for sealing against the inlet
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opening of the fan plenum assembly.
The base incl~des two substantially parallel beams
having legs at each end and a substantially rectangular
table secured to the beams. The table has a central
section secured to the parallel beams and opposite firsk
and second end sections extending from opposite ends of
the central section cantilevered outward from the
parallel beams. The canopy is secured on the parallel
beams whereby a portion of the bea~s project outward from
one side of the table and have the fan support secured
thereto.
In accordance with the invention, seal means between
- the fan plenum asse~bly and the powder collector seals
the exhaust opening of the powder collector against the
inlet opening of the fan plenum assembly. The seal means
includes a bracket and a pneumatic seal member securely
gripped therein. The seal member is constructed of an
elastomeric material wlth a cross section including a top
surface, two side walls, a bottom surface with an
upstanding rib and a hollow inner chamber wherein -the
seal member is normally in a collapsed, d~lated state
" where the upstanding rib is in a first position closer to
the top surface, and wherein the seal member can be
expanded to an inflated state where the upstandiny rib is
25 in a second position further away from the top surface
than in the first position. The seal means helps to
secure the powder collector in position. Also, a second
seal means between the fan support and the powder
collector seals an opening through a wall in the fan
; 30 support to the inlet opening in the powder collector.
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In ~ccordance with the i.nvention, a method of
sealing a powder collector against both a canopy of a
spray boo-th and against a fan plen~m assembly, comprises
the following steps. A base is provided which is secnred
to hoth a canopy having an exhaust opening and a fan
plenum assembly having an inlet opening. The base is
aligned with the conveyor and leveled ~hereby the exhaust
opening of the canopy and the inlet opening of the fan
plenum assembly are automatically, simultaneously
leveled. A powder collector having an inlet opening and
an exhaust openin~ is then leveled with respect to the
base whereby the inlet opening of the powder collec~or is
automatically aligned for sealing to the exhaust opening
of the canopy and the exhaust opening of the powder
collector is simultaneously aligned with the inlet
op~ning in the fan plenum assembly. Next, the exhaust
opening of the canopy is sealed to the inlet opening of
the powder collector and the inlet opening OI the fan
plenum assembly is pneumatically sealed to ~he exhaust
opening o-E the powder collector.
Further in accordance with the invention, a
cartridge mount assembly comprises a hollow cartridge
having a bottom plate with an internally threaded boss
secured to the inside wall of the bottom end OI the
cartridge. A tie rod extending through the cartridge is
threadably engaged at one end to the threaded boss and at
an opposite end to a support assembly. The support
assembly i5 adapted to be supported in an opening within
a powder collector whereby the cartridge is secured
against a top plate of the powder collector. A handle
~: extends through the tie rod to initially thread the tie
rod into the threaded boss before the cartridge is
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mounted into the collector. A spider assembly has a
center bushing and a plurality of truss arms affixed
thereto and projecting radially outward therefrom. The
outer ends of the truss arms are notched out to rest
against the periphery of the opening in the top plate of
the powder collector to support the cartridge therefrom.
Notches in the top plate engage the truss arms and
prevent rotational movement of the spider assembly. A
centering bracket on the tie rod engages the interior
wall of the cartridge and maintains a centerline of the
tie rod coincident with the centerline khrough the
cartridge to protect ~he threaded boss from torque caused
by a misaligned tie rod, particularly during
installation. The handle is used to pllll thP tie rod up
15 through the center bushing so that a nut can be threaded
onto tne uppe~ end of the tie rod to mount the cartridge
in the collector. A roll pin extends through the tie rod
to engage the b~shing and prevent the tie rod from being
unthreaded from the boss when the cartridge is removed
from the powder collector. A single installer can both
install and remove the cartridge.
BRIEF DESCRIPTION OF THE DRAWINGS
~,
The structure, operation, and advantages of the
presently preferred embodiment of the invention will
become further apparent upon consideration of the
following description taken in conjunction wikh the
accompanying drawings, wherein:
~ IG. 1 is a perspective view of a base structure
supporting a fan plenum and a spray booth in alignment
with each other and the conveyor, and showing a powder
collector prior to being positioned and sealed against
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the spray booth and the fan plenum, in accordance with
the invention;
FIG. 2 is a perspective view of a base structure
supporting a fan plenum and a spray booth in alignment
with each other and a powder collector positioned and
sealed against the spray booth and the fan plenum;
FIG. 3 is a perspective view of the base for the
spray booth and fan plenum of the powder coating system
illustrated in FIG. 1;
FIG. 4 is a perspective view of the base illustrated
in FIG. 3 with the fan plenum support structure mounted
thereto;
FIG. 5 is a perspective view of the base and fan
plenum support structure, as illustrated in FIG. 2, with
the fan plenum mounted to the fan assem~ly support
structure;
FI~. 6 is a perspective view uf the base with a fan
plenum support structure supporting the fan plenum, as
illustrated in FlG. 5, and the canopy located on the base
assembly in alignment with the fan plenum;
FIG. 7 is a view taken along line 7-7 of FIG. 5
illustrating the retractable seal assembly;
FIG. ~ is a view taken along line 8-8 of FIG~ 7
illustrating the seal assembly in its normal deflated,
retracted position;
FIG. 9 is a view taken along line 9~9 of FIG. 2
illustrating the seal assembly in the inflated, expanded
: position between the powder collector and the fan plenum;
:~ FIG. 10 is a view taken along line lO-10 of FIG. 1
illustrating the inlet opening to the powder collector;
: FIG. ll:is a top view of a cartridge filter assembly
resting on the top of the powder collector;
` FIG. 12 is view taken along line 12-12 of FIG. ll
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illustrating the cartridge fil~er and mounting assembly;
FIG. 12A is an enlarged section of F~G. 12; and
FIG. 12B is a view taken along line 12B-123 of FIG
12A.
DETAII,ED DESCRIPTION OF TXE INVENTION
Re~erxing to FIGs. 1 and 2, a powder coating system
10, intended for use as a powder coating booth 12 for
applying powder coating ~aterial on a production line
basis, includes provision for automatic recovery and
recirculation of the oversprayed powder in the syst~m.
The booth itself is of a generally conventional design
and includes a canopy 14 having entry and exit vestibules
; 16 and 18, respectively, at each end thereof through
which the ar~icle or part 20 to be coated can ~e
transporterd. Typically in such equipment, the article 20
to be coated is hung by a hook 21 from a conveyor system
22 to move slowly through the spray booth so that the
part is sprayed with one or more spray guns thro~gh an
s opening (not shown) in the side of the canopy o~poslte
, 20 the collector.
'~ ~ A powder collector 24 as illustrated in FIGS. l, 2
and 10 is mounted on wheels 26. The wheels 26 include
leveling means 27, which are preferably vertically
adjustable casters, to level the powder collector as
required for the particular floor conditions. The
collector, during operation of system 10, is located
adjacent an exhaust opening 28 in a side wall of canopy
14. The powder collector, best shown in FIG~ 10, has an
inlet opening 30 in a side wall thereof with a seal 32,
;30 preferably "D" shaped in cross section thereabout. The
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inlet op~ning 30 is adapted to mate with canopy exhaust
opening 28, as discussed below. A top plate 34 of the
collector (see FIG. 1) has an exhaust opening 36 which
fits under a fan plenum assembly 38 and is sealed against
a bottom wall portion 40 of fan plenum 38, as illustrated
in FIG. 9, disposed about an inlet opening 42, as
discussed in more detail below.
A principle feat~re of this invention is the
construction of a base 44 which enables the canopy 14 to
10 be automatically properly aligned with respect to the ~an
plenum assembly 38i so that a powder collector 24 can be
moved into and out of position and quickly aligned and
effectively sealed to both the exhaust opening ~S of
powder spray canopy 14 and inlet opening 42 of the fan
plenum 38. The ~ase 44, as illustrated in FIG. 3,
includes a rectan~ular table 46 having a central section
48 and opposite end sections 50 and 52 cantilevered
outward from opposite ends of the central section 48.
The table is supported on t~o substantially parallel
beams 54 and 56 which extend transversely to the length
of the table and have leg elements 58 at each end. Beams
54 and 56, which are positioned un~er the intersections
of the central section 48 and the opposite end sections
50 and 52, are secured to the table by means such as
~elding. The triangular braces 60, secured to the bottom
of the table and to the beams, provide additional
support. The parallel beams 54 and 56 project outward
from one side 62 of table 46 and form a base to which a
fan support 64 (See FIG. 4) is secured.
Leveling means 72 are provided on base 44 to
simultaneously level the fan plenum assembly 38 and
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canopy 14, as discussed in more detail below. Theleveling means includes vertically adjustable feet 72 at
the bottom of legs 580
The fan support 64, as illustrated in FIG. 4, has a
front wall 80 with an openiny 82 adapted to mate with the
exhaust ope~ing 28 (see FIG. l) of canopy 14. A
rectangular frame 84 around opening 82 provides a smooth
surface against which the ~IDi~ shaped seal 32 of the
powder colleotor is sealed, as discussed below. A plate
86, secured along the bottom edge of opening 82, is level
with the table 46 which forms the inner floor of spray
booth 12. Plate 86 extends into the inlet opening 30 of
collector 24 so that any powder which bui3.ds up on the
inner booth floor 46 can be easily swept into the
collector. The fan support 64 includes two parallel side
walls 88 and 90 secured to and extending substantially
normal to front wall 80. The lower surfaces of ~he side
walls are secured, by means such as welding or bolts, to
the upper surface of the portions of the parallei beams
54 and 56 which project outward from side 52 of table 46.
The upper sur*aces of side walls 80 and 90 are
perpendicular to the frame 84 and provide a support
surface on which the bottom of the fan plenum assembly 38
can be attached by means such as nuts and bolts, as
illustrated in FIG. 6.
An important feature of this invention relates to
the ability of the fan support 64 to maintain a
: perpendicular relationship between the opening 82 through
: the front wall 80 of fan support 64 and the inlet opening
; 30 42 of the fan plenum assembly 38. This relationship is
critical to enablè both the inlet opening 30 and the
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exhaust opening 36 of powder collector 24, which are
perpendicular to one another, to be quicXly and ~asily
aligned with and properly sealed to both the opening 82
through the front wall 80 of fan ~upport 64 and the inlet
opening 42 of the fan plenum asse~lbly 38. Once the
canopy 1~ is securely mounted on table 46, the side wall
of the canopy can be secured to the front wall 80 of the
fan support so that the exhaust opening 28 is immovably
aligned with the opening 82. Since the inlet opening of
fan plenum assembly 38 is securely mounted to the top
surface of sidewalls 88 and 90, which in turn are
perpendicular to the fronk wall 80, the inl t opening of
fan plenum assembly 38 is automatically aliyned to be
perpendicular with the opening 82 in the side wall o-f fan
15 support 64.
By establishing a perpendicular relationship between
the inlet opening 42 of the fan plenum and the opening 82
of the front wall of the fan support, the powder
collector 24 can be rolled into position, as illustrated
in FIG. 2, and simultaneously aligned with respect to the
canopy and the fan plenum assembly so that an e~:Eective
air tight seal can be achieved. That is, both inlet and
exhaust openings 30 and 36, respectively, of powder
collector 24 are located against fan support opening 82
and fan plenum inlet opening 42, respectively, so that an
air tight seal can be ~uickly and easily achieved, as
discussed in more detail below. An air tight seal is
very important to the proper functioning of the powder
coating system 10 because it enables more air entrained
po~der to be removed from powder coating booth 12, and
prevents escape of the powder from the booth into the
plant en~ironment and from the collector into the fan
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plenum.
Another aspect of the invention relates to the fan
plenum assembly being supported by the base 44 instead of
the canopy, as was often the case in the prior art. This
enables the c~nopy to be constructed of a lightweight,
non-metallic material, such as for example a plastic like
polypropylene. One advantage of a plastic canopy is that
the powder coating material does not have an electrical
attraction to the plastic and will not tend to stick to
the sides of the canopy as with a metal canopy. This is
particularly important when the color is changed and the
system has to be cleaned before a new color of powder is
sprayed. Further t the canopy can be made of a
translucent material which provides improved lighting
inside the spray booth to better enable a system operator
to monitor the system. Further, the plasti~ is light
weight which is more manageable to assemble and lower in
cost.
Referring to FIG. 10, there is illl~strated the front
of po~der collector 24 which has inlet opening 30. A
seal means 32, typically comprising an elastomeric seal
" with a "D" shaped cross section, is disposed around inlet
openlng 30. When the powder collector is in place, as
illustrated in FIG. 2, conventional latches, not shown,
attached to fan support 64 pull collector 24 against the
front wall 80 of fan support 64 and tightly compresses
seal 32 against the frame 84 to form an air tight seal
between the rear wall of the canopy and th~ inlet opening
30 of powder collector 24.
Another important feature of the present invention
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relates to a seal means 99 including a seal assembly 100
disposed about the inlet opening 42 in bottom 40 of the
fan plenum assembly 38, as illustrated in FIGS. 7, 8 and
The seal assembly 100 includes a retractable,
pneumatic seal member 102 secured in a bracket or
extrusion 104. Extrusion 104 has an upper ~all 105 which
is secured to bottom wall 40 by any means suoh as spot
welding. Oppositely disposed, bracket side walls 106 and
108, extending dow~ward from upper wall 105, converge
inward toward each other and then turn outward to form
oppositely disposed cur~ed recesses 110 and 112 whi.ch
grip the top edges of seal member 102. The seal member
102 is preferably constructed of an elastomeric material
and has a normal deflated, retracted shape, the cross
section of which is illustrated in FIG. 8, including an
upper surface 114, two side walls 116 and 118 which
project downward`from the upper surface 114 and initially
converye inward to form shoulders 120 and 122 and then
diverge outward to form inwardly curved troughs and
lower, outwardly rounded corners 124 and 126 which
intersect at rib 128 haviny a jagged, outwardly facing
surface 130. The seal member 102 also has a hollow inner
chamber 132.
As illustrated in FIG. 9, after the powder collector
24 is in place under fan plenum 38, seal member 102 is
inflated with air into its expanded condition so that the
hollow inner chamber forms a substantially circular cross
section forcing rib 128 outward away from bottom surface
114. In this position, the surface 130 of rib 128
compresses against the top plate 34 of collector 2~ and
forms an air tight seal around powder collector exhaust
opening 36 and fan plenum inlet opening 42.
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When the seal assembly loo is in the retracted
- position of FIG. 8, powder collector 24 can be moved in
or out from under fan plenAm 38 to replace the collector
when a new color is be~ng sprayed or the cartridge
filters need replacing. That is, when the powder
collector is rolled under the fan plenum assembl.y, the
seal 102 is in the retracted position and does no~
interfere with the collector being moved into position.
After the collector is positioned so that both its inlet
and exhaust openings 30 and 36, respectively, are aligned
with fan support opening 82 and fan plenum assembly inlet
opening 42, respectively, collector 24 is secured in
place with a latch mechanism, as previously discussed, to
pxovide an air tight seal ~etween the rear wall of canopy
14 ~nd the inlet opening 30 into powder collector 2~.
The seal assembly 100 is then inflated into the expanded
position of FIG. 9 to compress seal 102 against the
collector's upper plate 34 and form an air tight seal
between exhaust opening 36 and air plenum inlet openin~
42. The pneumatic seal exerts a downward force on
collector 24 and thus additionally functions to secure
the collector 24 in position. Thus, even if collector 2.
is inadvertently unlatched, it is still secured with
; ' respect to the fan plenum because of the downward force
from seal assembly lO0. When collector 24 is to be moved
: out from under fan plenum 38, the seal is simply deflated
and it contracts to its normal deflated condition, as
illustrated in FIG. 8, so as not to interfere with the
movement of the collector.
A further advantage of inflatable seal 100 is that
it can account to some deyree for cases where the top
: of the collector 24 is not completely level with respect
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to the bottom of fan plenum 38. That is, even where
these two components are not completely level with
respect to one another, an effeckive seal will be made
between collector 24 and fan plenum 38 by means of
pneumatic seal 100, because pneumatic seal 100, being
resilient, can correct to some degree for misalignment
between collector 24 and fan plenum 38. This ls yet
another way in which the presenk invention facilitates
the quick and easy leveli.ng and sealing of collector 2
with respect to fan plenum 38 and booth canopy 14.
Anoth~r important feature of the present i.nvention
relates to the mounting of hollow, cartridge filters 120
to the top plate 34 of the powder co]lector 24, as
generally illustrated in FIG. 1. The filters 120 are
suspended from a support assembly 12 , as explained in
detail below. The cartridge filters 120, as illustrated
in ~IGS. 11 and 12, include an elongated hollow member
124. formed of a filter media, such as a cylindrically
shaped, filtering wall with a pleated outer surface and a
hollow interior disposed about a longitudinal centerline
125. The cartridge filter 120 has a closed bottom end
cap 126 with an internally threaded boss 128 secured to
the ~ottom end thereof and an open top end cap 130
secured to the top end thereof.
As illustrated in FIG. 12, a tie rod 132 is threaded
at both ends 134 and 136 and extends through the hollow
interior of cartridge filter 120. Tie rod 132 is
threadably engaged at end 134 to threaded boss 128 and at
the opposite end 136 to support assembly 122. Between
: 30 ends 134 and 136 is a handle 138 extending transverse to
~ a centerline 140 through the tie rod. In the preferred
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embodiment, the handle is secured in a bore 1~2 through
rod 132. The handle enables an assembler to easily
rotate the tie rod and thread or unthread it from the
; ~oss 128. A roll pin 144, located near the threaded
portion of end 136, extends transversely to centerline
140 through the tie rod and is preferably secured in and
extends outward from both sid~s of a bore 146 through rod
132 (See FIGS. 12A & 12B). The roll pin 144 engages a
slot 148 in a bushing 150 to prevent the rotation of tie
lo rod 13~ when the cartridge i~ being disassembled from the
support 1~2, as discussed below. Note that roll pin 144
is located adjacent the shoulder 152 formed at the
intersection of the threaded and unthreaded sections of
tie rod 132. While a single roll pin is illustrated, an
additional roll pin can be installed in bore 153 if
desired.
A tie rod centering bracket 154, as seen in ~IGS. 11
and 12, is formed of a circular plate 156 having a hole
158 through its center to freely xeceive the tie rod 132.
A plurality of radial extending arms 159, preferably
four, are each attached at one end to the plate 156 and
have an upstanding leg 160 at the other end. The radial
'~ arms 159 are spaced at substantially 90 degrees with
respect to each other. The ups-tanding leys 160 abut
against the inner surface o~ the cartridge and prevent
radial movement of the bracket. The free ends of -the
legs are bent to form a stop 162 which rests against the
top end 130 of the cartridge to hold bracXet 154 in
place. Bracket 154 functions to center the tie rod
within ~iIter 120. That is, bracket 15~ insures that the
centerline 140 of the tie rod essentially coincides with
. ~
the centerline 125 of cartridge 120. This alignment
19
.
?~ 7, 9
prevents the tie rod 132 from moving out of alignment
with the centexline 125 of caxtridge 120 during
installation or removal of cartridge 120 which would tend
to break the boss 128 or deform end cap 126.
Support assembly 122 is adapted to support the
fi.lter cartridges 120 below openings 36 in the ~op plate
34 of powder collector 24 whereby the cartridge is
secured with a tight seal against the bottom side 172 of
top plate 34. Support assembly 122 includes a spider
assembly 174 comprised of center bushing 150 and a
plurality of trl~ss arms 176, 178 and 180 affixed thereto
and projecting radially outwar~ at an angle of about 120
degrees with respect to each other. The outer ends of
the truss arms are notched out so that an inner
upstanding surface rests in a notch 181 e~tending
radially outward from the periphery of opening 36, as
seen in FIG. 11, to prevent rotational or radial movement
of spider 174. The radial extending surface of the notch
in khe truss arms rests on the top surface of plate 34
and supports the cartridge within powder collec~or 24.
To assemble a cartridge 120 into the powder
collector 24, tie rod 140 is threaded into the internal
threaded boss 128, centering bracket 154 is inser.ed onto
the rod 140 in cartridge 120, and cartridge 120 is placed
in the powder collector through the inlet opening 30.
The perforated baffles shown in FIG. 10 are removed
during this step so that the interior of collector 2~ is
completely open. Support assembly 122 is then secured
across opening 36. The assembler then reaches into the
opening 36 through the top plate 34 and ho-ding handle
138 pulls up cartridge 120 so that the upper threaded end
:::
~ 2~
~ .
. '
", " , ", i . . . ; . `' t ' ' i' ' ' ' , , i,, ' ' ' '
of rod 132 passes through bushing 150, with roll pin 144
inserted into slot 148 of bushing 150. The assembler
pulls up on h~ndle 138 until seal 182 of cartridge 120
rests against the bottom surface 1'72 of plate 34. Next,
a nut 183 is threaded onto the upper ~hreaded end of tie
rod 132 and tightened to compress gasket 182 and seal
cartridge 1~0 around inlet hole 360
When the cartridge is to be removed from the powder
collector, the nut 183 is unthreaded. As the nu~ is
turned in the counterclockwise direction to unthread i-t,
roll pin 144 engages slot 148 in bushing 150 to prevent
tie rod 132 from turning and being unthreaded from the
threaded boss 128.
The patents listed herein are intended to be
incorporated by reference in their entireties,
It is apparent that there has been provided in
accordance with this invention apparatus and methods for
sealing a powder collector assembly against a spray booth
and a fan plenum assembly and a cartridge mount assembly
that satisfy the objects, means and advantages set forth
hereinbefore. According to the invention, a powder spray
canopy is aligned with a fan plenum assembly by a fan
support bracket which is itself supported by the base
which supports the canopy so that a powder collector can
be quickly aligned and effectively sealed to both the
powder spray canopy and the fan assembly. A pneumatic
seal is provided between the fan plenum and collector to
facilitate this operation. A support assembly is provide
: ~ for the filter cartridges which enables an assembler to
; '0 easily and quickly install and remove the filter
21
,
,
:
211 ~6~
cartridge as needed from the powder collector.
While the invention has been described in
combination with embodiments thereof, it is evident that
many alternatives, modifications, and variations will be
apparent to those skilled in the art in light of the
foregoing teachings. Accordingly, the invention is
intended to embrace all such alternatives, modifications
and variations as fall within the spirit and scope of the
appended claims.
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