Note: Descriptions are shown in the official language in which they were submitted.
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This invention generally relates to constructions
utilized for collecting powder to thereby reduce the amount
of powder present in the atmosphere. The invention is par-
ticularly directed to a powder collecting construction for
use in association with applicators which apply powder to
moving surfaces such as the surfaces of sheets passing from
a printing press.
Electrostatic powder sprayers are widely employed
as a means for applying anti-offset powders to the printed
surfaces of sheets, webs and the like after issuing from a
printing press. Typically, the powder employed comprises a
random mixture ranging in size from 5 to 100 microns. In
practice, particulate of a size of 20 microns or greater
will, due to the influence of the applicator and gravity, be
applied to the surfaces and provide the offset protection.
Smaller particles, however, have a tendency to become air-
borne particularly due to the air currents which may be gen-
erated by the printing machine and by conveying systems used
for the printed material~
; 20 Attempts have been made to provide structures for
purposes of removing at least substantial a~ounts of the
powder from the atmosphere surrounding the applicator to
thereby minimize the nuisance. An apparatus for removing
powder is described in U.S. Patent No. 3,680,528.
It is a general ob~ect of this invention to provide
a highly effective means for achieving powder removal in con-
junction with a system involving the application of powder to
printed surfaces and the like.
It is a more specific ob~ect of this invention to
provide a construction for powder removal which is highly
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versatile in nature in that the construction can be effectively utilized in
conjunction with systems of various sizes.
It is a still further object of this invention to provide a
construction of the type described which can be readily modified to
accommodate different needs whereby maximum effectiveness can be achieved
without encountering extensive design and manufacturing expenses.
According to the present invention, there is provided in a system
for applying powder to a moving surface wherein the powder is sprayed from
an applicator, the improvement comprising means located adjacent the
applicator for collecting excess powder from around the applicator to thereby
reduce the presence of the powder in the surrounding atmosphere, said
collecting means comprising a plurality of modules, each module comprising
enclosing walls including end walls and interconnected side walls, inlet and
outlet openings defined by each module, means supporting the modules in
end-to-end assembly adjacent said appiicator, the assembly of modules
extending substantially across said moving surface, individual conduits con-
nected to each of said outlet openings, and suction means connected to said
conduits whereby powder in the air around the applicator is pulled simultane-
ously into the respective inlet openings and collected through said conduits.
Specific embodiments of the present invention are now shown, by
way of example only, with reference to the accompanying drawings in which:
Figure 1 is a side elevational view illustrating a powder
collecting means in conjunction with an electrostatic spraying system;
Figure 2 is a plan view of the arrangement shown in Figure l;
Figure 3 is a perspective view of a collecting module utilized
in constructions of the type contemplated by the invention;
Figure 4 is a bottom perspective view of the module shown in
Figure 3;
Figure 5 is a perspective view of the module as shown in Figure
4 with the deflector plates removed and with a wall portion partly cut away;
Figure 6 is an enlarged cross-sectional view of the module taken
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about the line 6-6 of Figure 4;
Figure 7 is a cross-sectional view of the module provided with
different deflector plates;
Figure 8 is a perspective view of an exhaust manifold construction
utilized in accordance with the concepts of
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the invention; and,
Figure 9 is a vertical, sectional view of the mani-
fold construction.
The construction of this invention is designed for
use in a system wherein powder is sprayed or otherwise ap-
plied to a moving surface. The invention is specifically
applicable to the collection of powder whereby undesirable
amounts of powder can be prevented from entering the atmos-
phere surrounding the powder applying mechanisms.
The particular collecting means of the invention
comprise modules which define enclosing walls including end
walls and which are each provided with inlet and outlet open-
ings. The modules are adapted to be mounted on a common sup-
port in end-to-end relationship, and conduits are connected
to the outlets of each module. The conduits are in turn con-
nected to a suction system whereby powder is adapted to be
collected by the individual modules and then transported by
the respective conduits to an area where the powder can be
disposed of orsutilized for other purposes.
sy employing the individual modules which may be
dimensioned with a length between about 8 to 12 inches, pref-
erably lO inches, a collection construction can be readily
set up for powder applicators of different sizes. Thus, the
arrangement of the invention provides for the mounting of
the individual modules in end-to-end relationship so that the
length of the assembly of modules can be readily varied to
suit a particular need.
The modules are preferably provided with deflector
plates designed to direct powder through the module inlet
3 openings. These deflector plates are adjustable and are
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preferably positioned along opposite edges of the inlet open-
ings so that the size of the inlet opening~ can be varied to
suit a particular need. In addition, sliding gate members
are preferably associated with the~module outlet openings so
that the dimensions of these openings are also variable. Such
variations are quite helpful in designing a particular module
set-up since the collection function of individual nozzles in
a single assembly can vary depending upon the particular ap-
plication involved.
The invention also contemplates the provision of an
exhaust manifold which is adapted to be connected with each
conduit. The manifold structure permits the association of
several conduits with a single exhaust pipe being employed for
receiving all of the powder collected from the several con-
duits. The manifold design is such that two or more groups
of modules can be provided at different locations around a
powder applicator wîth all of the conduits extending from the
modules to the same exhaust manifold.
In the drawings, Figures 1 and 2 illustrate a sys-
tem including a powder applicator structure 10. The appli-
cator structure, which would typically be an electrostatic
powder sprayer, comprises a hopper 12, and a drive motor 14
which drives metering roll 16. As shown, powder drops down-
wardly from the sprayer toward the lower flight 18 of a con-
veyor. This conveyor is provided with a gripping means 20 ofany conventional design whereby printed sheets 22 can be moved
from a printing press (not shown) into positi~ opposite the
powder sprayer. When the anti-offset powder has been pro-
vided on the printed surface, the individual sheets are
3 dropped by the gripping means into a stack located beneath
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the lower flight of the conveyor.
The powder collecting means of the invention in-
cludes a plurality of modules 24 positioned adjacent the ap-
plicator 12. These modules are attached to a rail 25 or
other supporting means attached to frame means (not shown)
so that the modules form an assembly extending across the
conveyor for approximately the same distance as the powder
sprayer.
Each module has attached thereto a conduit 26 with
the conduit extending to an exhaust manifold 28. The exhaust
manifold in turn is provided with a centrally located exhaust
pipe 30. As shown, the conduits 26 extend outwardly beyond
the sides of the;~upper flight 32 of the conveyor so that
these conduits do not interfere with the conveyor movement.
A separate set of modules 24 may be mounted above
the upper flight 32 of the conveyor, and separate conduits
36 are utilized for connecting these modules to the e~haust
manifold 28. It will be appreciated that with the arrange-
ment of the invention, the modules may be positioned at dif-
ferent locations depending upon the physical arrangement of
the conveyor and applicator structures as well as the physi-
cal arrangement of the surrounding area. One alternative to
the specific arrangement illustrated in Figure 1 would be the
location of an assembly of modules forwardly of the applica-
tor 10 with the motor 14 and associated mechanisms being re-
located, if necessary, to provide an optimum location for
these modules.
The modules 24 are designed to assume various posi-
tions and forms. As illustrated in Figures 3-7, the modules
comprise a wall 38 for supporting cylindrical coupling element
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47 and opposing wall. A short wall 40 is opposed by solid
wall 42, and walls 44 are found at each end. The wall 38 de-
fines a circular outlet opening communicating with coupling
element 47 for passage of air and powder into an associated
conduit. The conduit may be secured~ by press fitting or
other conve ntional means.
A pair of sliding gates 48 are attached to the under
side of the wall 38 by means of fasteners 50. These fasten-
ers are received in slots 52 so that the gates can be moved
to vary the effective size of the outlet opening.
In Figures 3, 4 and 6, deflector blades 54 and 56
are secured, respectively, to the walls 40 and 46 of the mod-
ules. Fasteners 58 are received in slots 60 defined by blade
54 whereby the position of this blade can be varied relative
to the edge of the front wall 40. Similarly, fasteners and
slots are utilized for securing blade 56 whereby the position
of this blade can be adjusted relative to the position of
bottom wall 460 The blades 54 and 56 serve to define inlet
openinys for each module, and the extension of one blade hori-
zontally and the other vertically provides a funnel-like
arrangement which will tend to direct large portions of air-
borne powder into the individuall~modules.
The modules 24 immediately adjacent applicator 12
are disposed as shown in Figure 6 whereby the conduits ex-
tend from the sides of the modules. The attitude shown in
Figure 3 is also feasible where it would be more convenient
to extend the conduits from the top of the modules, for exam-
ple for space considerations~ The deflector blades 54 and
56 are interchangeable so that if a particular application
3 calls for one blade being longer than the other, then all of
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the same parts can be used for any position of the blades.
Figure 7 illustrates a module 24 wherein a
straight deflector blade 76 is attached by means of fasten-
ers 7~3 to the side wall 40. A second straight deflector
blade 84 is attached by means of fasteners 86 with the po~i-
tions of both blades being adjustable. Figure 1 illustrates
an application of straight deflector blades 76 and 84 on mod-
ules 24. An angle 88 is provided for supporting this group
of modules~
The straight blades 76 and 84 are preferably uti-
lized as stock material for forming blades 54 and 56. It
will be appreciated that this permits formation of deflect-
ing surfaces of different sizes depending upon where a bend
is made in the stock material. In addition, the angle of a
bend can vary so that any application can be accommodated in
the most efficient manner.
The described module configurations are designed
for inclusion in an assembly with the end walls of the mod-
ules preferably located immediately adjacent each other. This
permits efficient collection of powder due to the fact that
each module can be,~individually adjusted so that greater or
lesser collection can be attained at different points along
the length of the assembly. This can be particularly effec-
tive where the non-uniform suction will tend to increase the
percentage of powder collected, and a degree of experimenta-
tion can determine the most efficient arrangement after a mod-
ule assembly has been set up.
The exhaust manifold 28 is illustrated in detail
in FigureS 8 and 9. This manifold defines downwardly extend-
3 ing top surfaces 94 on either side of the exhaust pipe 30,
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and a plurality of openings 96 are defined by each top wall.Coupling elements 98 are utilized for attaching the ends of
conduits 26 and 36 extending from the modules 24. The bot-
tom wall 100 preferably peaks beneath the exhaust pipe 30 to
direct powder entering the manifold upwardly into the pipe.
The coupling elements 98 are preferably formed on
plates 102 which can be attached to the manifold to span
large openings in the manifold top walls. As illustrated in
Figure 8, provision is made at 104 for removing additional
sections of the top wall whereby additional plates 102 can
be added to thereby increase the number of conduits directed
to the exhaust manifold. Thus, the design of the exhaust
manifold adds further to the versatility of the system by
providing, in the embodiment illustrated, for the connection
f as many as 16 conduits.
The exhaust manifold is supported on a plate 106
which is positioned above the upper flight 32. This plate
serves as a housing portion tending to prevent airborne par-
ticles from rising about the level of the plate.
One or more gates 108 are provided for the plate
106 to provide access to the assembly of modules 24 and to
the applicator structure. Otherwise the plate 106 defines
appropriate openings for mounting of the upper assembly of
modules while also providing a suitable mounting surface for
the exhaust manifold.
It has been found that the structures described are
e~ceptionally effective for purposes of collecting particu-
late material particularly the material in the 5 to 20 microns
range which represents the most troublesome material. This
3 collection is accomplished without disrupting the passage of
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the larger particles onto the moving surfaces.
~ he structures of this invention do not require
the massive amounts of air and large blower and energy out-
puts which characterize other systems, Where large displace-
ments of air are required, it has been found that the sheetdelivery systems and the powder application to the sheets
can be adversely affected unless the removal means are lo-
cated in out of the way positions so that large amounts of
the troublesome particles cannot be collected.
sy utilizing individual modules in the order of
10 inches long, various module assemblies can be obtained
without any significant increase in manufacturing and assem-
bly costs. Thus,custom collection systems can be provided
without the necessity for t~e custom design of air nozzles,
exhaust manifolds, etcetera.
In applicant's arrangement wherein the collection
assemblies are located closely adjacent the powder delivery
hopper as shown in Figure 1, the nuisance powder is collected
before being distributed into the surrounding atmosphere. A
low amount of suction;is required because of the proximity
of the module assembly thereby reducing the power require-
ments as well as the volume of air in the collection system.
Although the arrangement of Figure 1 is preferred,
the utilization of only an upper module assembly can be effec-
tive where space limitations prevent the insertion of the
lower assemblies. As noted, the addition of other module
assemblies at other locations ic also contemplated. Such
additions can include mounting of a module assembly under-
neath the hopper below the lower conveyor flight.
3 It will be understood that various changes and
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modifications may be made in the above described construc-
tion which provide the characteristics of the invention
without departing from the spirit thereof particularly as
defined in the following claimsO
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