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Claims  |
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We claim:
1. A device for transporting objects to be treated with spray and for
collecting and removing excess spray comprising
transport means for objects lying thereon;
collection means for collecting excess spray medium which passes by the
objects and the transport means, said collection means comprising an
endless belt which is independent of said transport means,
a removal device for removal of excess spray medium from said belt; and
trace-forming means for bringing together the excess spray medium on the
belt to at least one trace of spray medium which is narrower than the
width of the belt;
wherein said removal device is positioned and arranged for removal of the
trace(s) from the belt.
2. The device for transporting objects to be treated with spray and for
collecting and removing excess spray of claim 1 wherein the trace-forming
means form a single trace of spray medium in the center of the belt.
3. The device for transporting objects to be treated with spray and for
collecting and removing excess spray of claim 1 comprising means for
controlling a rotation velocity of the belt for collecting excess spray
medium, wherein the rotation velocity of the belt for collecting excess
spray medium is higher than a velocity of the transport means.
4. A device for supporting objects to be treated with spray and for
collecting and removing excess spray compromising
support means for objects lying thereon;
collection means for collecting excess spray medium which passes by the
objects and the support means, said collection means comprising an endless
belt which is independent of said support means;
a removal device positioned and arranged for removal of said excess spray
medium from said belt; and
wherein said support means comprises threads stretched over the belt, said
threads being stretched between holders which are mounted on sliding
carriages.
5. A device for transporting objects to be treated with spray and for
collecting and removing excess spray comprising
transport means for objects lying thereon;
collection means for collecting excess spray medium which passes by the
objects and the transport means, said collections means comprising an
endless belt which is independent of said transport means, and a removal
device positioned and arranged for removal of said excess spray medium
from said belt;
wherein the transport means and the belt are pivotal around a horizontal
axis and can be raised by a pneumatic adjusting device.
6. A device for supporting objects to be treated with spray and for
collecting and removing excess spray comprising a support for the objects
with collection means for collecting excess spray medium passing by the
objects and the support, the collection means comprising
an endless rotation belt independent of said support;
trace-forming means for bringing together excess spray medium on the belt
to at least one trace of spray medium which is narrower than a width of
the belt, and
a removal device positioned and arranged for removal of said trace(s) from
the belt.
7. The device for supporting objects to be treated with spray and for
collecting and removing excess spray of claim 6 wherein the trace forming
means comprises at least one lip positioned at an angle with respect to
the direction of the belt's rotation, the lip being elastically pressed
against the belt.
8. The device for supporting objects to be treated with spray and for
collecting and removing excess spray of claim 7 wherein the lip is
fastened to a support are being adjustable in relation to the belt.
9. The device for supporting objects to be treated with spray and for
collecting and removing excess spray of claim 7 wherein the lip is made of
an elastic material.
10. The device for supporting objects to be treated with spray and for
collecting and removing excess spray of claim 9 wherein the lip is made of
a thin metal blade.
11. The device for supporting objects to be treated with spray and for
collecting and removing excess spray of claim 7 wherein a side of the lip
facing the excess spray medium on the belt forms an acute angle (.alpha.)
with the belt surface.
12. The device for supporting objects to be treated with spray and for
collecting and removing excess spray of claim 6 wherein the removal device
comprises at least one pipe which is elastically pressed against the belt.
13. The device for supporting objects to be treated with spray and for
collecting and removing excess spray of claim 12 wherein said belt is
directed over a guide roller and the at least one pipe is pressed against
the belt in a region of the guide roller.
14. The device for supporting objects to be treated with spray and for
collecting and removing excess spray of claim 6 further comprising a
device for application of an additive agent to the belt.
15. The device for supporting objects to be treated with spray and for
collecting and removing excess spray of claim 14 wherein the device for
application of the additive agent comprises at least one nozzle for
spraying of the additive agent on the belt.
16. The device for supporting objects to be treated with spray and for
collecting and removing excess spray of claim 14 wherein the device for
application of the additive agent comprises at least one application
roller for applying a blending agent on the belt.
17. The device for supporting objects to be treated with spray and for
collecting and removing excess spray of claim 14 wherein the device for
application of the additive agent comprises at least one applicator
staying in contact with the belt, the applicator being made of porous or
fibrous material.
18. The device for supporting objects to be treated with spray and for
collecting and removing excess spray of claim 17 wherein the applicator is
made of a felt.
19. The device for supporting objects to be treated with spray and for
collecting and removing excess spray of claim 14 wherein the device for
application of the additive agent is positioned so that the additive agent
impacts the belt before the excess spray medium impacts the belt.
20. The device for supporting objects to be treated with spray and for
collecting and removing excess spray of claim 14 wherein the device for
application of the additive agent and the trace-forming means are an
integrally formed unit.
21. The device for supporting objects to be treated with spray and for
collecting and removing excess spray of claim 14 wherein the additive
agent is a lacquer solvent.
22. The device for supporting objects to be treated with spray and for
collecting and removing excess spray of claim 6 comprising means for
controlling a rotation velocity of the belt for collecting excess spray
medium, wherein the rotation velocity of the belt for collecting excess
spray medium is controllable at a constant rate.
23. The device for supporting objects to be treated with spray and for
collecting and removing excess spray of claim 6 wherein the belt is guided
over two rounded supports between which the belt is unsupported and at
least a portion of the trace-forming means is pressed against the belt
suspended in a region between the two rounded supports.
24. The device for supporting objects to be treated with spray and for
collecting and removing excess spray of claim 6 wherein the belt is guided
over a triangular arrangement of rollers (50a), (50b), and (50c), whereby
the collection of excess spray medium and its removal from the belt takes
place at different sides of the triangular arrangement.
25. The device for supporting objects to be treated with spray and for
collecting and removing excess spray of claim 24 wherein the triangular
arrangement of rollers forms a right triangle.
26. A device for supporting objects to be treated with spray and for
collecting and removing excess spray comprising a support for the objects
and collection means for collecting excess spray medium passing by the
objects and the support, the collection means comprising an endless belt
independent from said support wherein the support comprises thin threads
stretched over the belt, said threads being stretched between holders
which are mounted on sliding carriages.
27. A device for supporting objects to be treated with spray and for
collecting and removing excess spray comprising
support means for objects thereon;
collection means for collecting excess spray medium which passes by the
objects and the support means, said collection means comprising an endless
belt which is independent of said support means, and a removal device
positioned and arranged for removal of excess spray medium from said belt;
wherein the support means and the belt are pivotal around a horizontal axis
and can be raised by a pneumatic adjusting device. |
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Claims |
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Description |
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BACKGROUND OF THE INVENTION
The invention relates to a spray-treatment device, in particular to a
device for spray-painting of objects comprising a transport means or a
support for the objects, and collection means for collecting the excess
spray medium passing by the objects and the transport means.
With the application of the spray medium (i.e. spraying of liquid lacquer
or powder) on the objects (work piece) the problem arises to remove the
spray medium which does not reach the objects while subsequently complying
with environmental laws.
It is known to combine the excess spray medium (overspray) with coagulating
agents dispersed in water, thus extracting a sediment. The resulting
sediment is, of course, hazardous waste, which is problematic and costly
to remove. In addition, the water's surface is not arranged in a favorable
spatial position for collection and a highly mechanical/technical effort
is necessary in order to incorporate this technology.
Furthermore, it is known to send the objects on conveyer belts through an
automatic spray-machine to mechanically remove deposited spray-medium
excess by scraping or abrasion. This system serves mainly for the
purification of the conveyer belt.
The desired collection of the excess spray-medium in conjunction with
recycled use is not evident. Moreover, the conveyer belts must be dried
after the abrasion before they come in renewed contact with the objects.
The speed of the excess spray-medium is pegged to a slow conveyor speed of
the objects in the spray machine, whereby a considerable amount of time
passes between the spraying of the spray medium and the collection of the
excess from the conveyor belts. This leads to increased evaporation of the
solution, not only imposing a greater environmental burden, but also
hindering collection of the spray-medium on the conveyor belts.
Furthermore, it is also known in DE-OS 28 23 958 to provide a
spray-compartment in which the objects are suspended on hooks, in order to
form, by means of a rotating belt, a vertical curtain for the preliminary
spray medium on the objects, thereupon the deposited spray-medium on the
belt is mechanically stripped off the belt.
SUMMARY OF THE INVENTION
According to one aspect of the invention, the invention is based on an
automatic device for spray treatment in which the objects are moved
continuously or step by step by a transport means or support. In order to
collect as much as possible of the excess spray-medium passing by the
objects, and to approach the concept of recycling, the invention provides
that the collection means comprises an endless belt independent of said
transport means or support. Furthermore, there is a removal device for
removal of spray medium from the belt.
Thereby the transport means is favorably formed exposing the least possible
surface to the spray medium, i.e. advantageously e.g. with two or more
adjacent narrow conveyor belts. On the side of the objects averted from
the spraying nozzles, the endless collection belt rotates, from which the
impacted spray medium is removed by means of a removal device touching the
belt.
It is essential that the rotating belt used for collection of the excess
spray medium is moveable independently of the transport means (preferably
narrow adjacent conveyer belts). It is possible to adjust the speed of the
collection belt independently of the speed of the objects going through
the spray system. It is thus possible to conform the conveyor speed to
each specific spray medium with continuous speed regulation of the belt.
It is especially possible to allow the collection belt to run essentially
faster than the conveyor speed for the belt responsible for transport of
the objects through the spray device. Thereby an excessive evaporation of
the solvent of the lacquer can be reduced, which on the one hand protects
the environment and on the other hand allows for easier removal of the
lacquer from the belt due to lower viscosity.
The collection belt can advantageously be arranged across the conveyor
direction of the transport means. Thus a favorable arrangement of the
collection belt removal device as well as the accompanying drive unit is
possible. Also such a device for the collection of the excess spray-medium
is easily applicable to many existing types of automatic spray treatment
devices.
Especially with larger systems (wide belts for the collection of excess
spray medium) the problem arises for complete removal of the spray medium
from the collection belt. The invention intends to solve this problem by
means of impressed lips forming one or more traces of the medium on the
belt whose width is essentially smaller than the belt width. In a second
step, these spray medium traces are completely removed by a removal unit
from the belt. By this also the border region of the belt may be reached.
Moreover, this seperation of trace-forming removal allows for structural
components, which are specifically designed and adapted for their use,
thus facilitating an improved removal as well as easier operation
(especially a cleaning of the belt is possible when the color of the
medium is changed).
Such two-stage removal (first a trace of the spray medium is formed on the
collection belt and then this trace is removed) may also be used for spray
treatment devices where the objects are not automatically moved through a
transporter but rather are secured on an fixed support. Further features
of the invention may be used not only for spray-treatment-devices with
automatic transportation of objects, but also the feature of installing
stationary supports.
In order to comprehend these two possibilities with a single expression,
the present application uses the expression "support" not only for
stationary supports but also for movable supports, i.e. transport means in
an automatic spray treatment device.
DESCRIPTION OF THE DRAWING
Further advantages and features of the invention will be described in more
detail in the following description of the drawings:
FIG. 1 shows a schematic representation (side view) of the inventive spray
treatment device where the objects are automatically moved by a
transporter,
FIG. 2 shows a schematic representation of FIG. 1 from the top view,
FIG. 3 shows a side view of the belt for collection of the excess spray
medium which is collected by a haul-off device,
FIG. 4 shows a top view of FIG. 3,
FIG. 5 shows a front view of FIG. 3,
FIG. 6 shows a detail of a device for insertion of an additive agent
(solvent) and a lip for formation of a trace,
FIG. 7 shows a top view of FIG. 6,
FIG. 8 shows a spray treatment device, whereby the objects are placed on a
stationary support, with a specific embodiment of the system for
collection and removal of the excess spray medium,
FIG. 9 shows a top view of FIG. 8,
FIGS. 10, 11 show a schematic representation of an embodiment from the
side-view, whereby the support can be turned up with the belt for the
collection of the excessive spray medium,
FIG. 12 shows a schematic representation of longitudinal view of the
embodiment of a belt for collection of excessive spray medium,
FIG. 13 shows a schematic representation for illustration of the recycling
of the collected spray medium (lacquer),
FIGS. 14a-f show variations of the invention in a top-view of the belt for
the collection of the excessive lacquer material,
FIGS. 15a-e show variations of the invention in a schematic representation
(side-view) of the belt for the collection of the excessive spray medium,
FIGS. 16a-c show variations of the invention in a schematic representation
of the belt with application of blending agents,
FIGS. 17a-c show variations of the invention in a schematic representation
of the belt with belt guidance in a triangle, and
FIG. 18 shows a special belt support.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIGS. 1 and 2 show an automatic spray (lacquer) treatment device of objects
with a transport means (1) which moves the desired objects through the
actual spray chamber (2). The spray medium is applied onto the objects (4)
by spray nozzles (3) overhead.
In order to collect the excess spray medium passing by the objects
(overspray) (4), a rotating belt (5) is provided underneath the transport
transport means (1). The upper-half of the endless belt, which is directed
over guide rollers (6) (from which it is driven), lies parallel precisely
beneath the support for the objects (4), which according to the
embodiments of the invention, are formed through multiple rotating narrow
conveyor belts of the transport means (1). The gap between the conveyor
belts is larger than the actual belt width, thus offering the least
possible surface to the spray medium and the majority of the diverted
spray medium lands on the belt (5). The belt for the collection of the
spray medium runs perpendicular to the direction of the transporter (1).
This permits a parallel guidance of the belt (5) underneath the
transporter (1), whereby the not yet mentioned trace-forming lips (7) and
the removal pipe (8) can be arranged exterior to the transport means (1).
Thus the spatial arrangement is optimally utilized and said collection
belt, including the removal device, can be supplemented to existing
automatic spray systems. The precise guidance of the belt (0.2 mm to 5 cm,
preferably 0.2 mm to 2 cm) beneath the support for the objects (4)
prevents an unwanted exposure of excess lacquer material (overspray)
underneath the objects (4).
According to a preferred embodiment of the invention, the collection of the
spray medium on the belt (5) takes place by first forming a narrow trace
(9) on the belt (narrower than the belt width), whereby the spray medium
is then removed by a removal device from the belt. According to the
invention the trace formation means comprises two elastic lips (7) pressed
against the belt (5), placed at a slight angle with the belt's (5)
direction of transport (10) and thus forming a single trace (9) of spray
medium in the middle of the belt (5). In the preferred embodiment the lips
are made of an elastic material, preferably a thin metal blade. This trace
(9) can be easily and completely removed by a collection pipe (8)
elastically pressed against the belt from below.
In FIGS. 3 through 5, further details of the belt (5) and the removal
system for the spray medium are characterized. On a frame (11), arms (12)
for the lips (7) are mounted to revolve around a vertical axis (13).
Moreover, the arms (12) can be moved in the direction of the arrows (14),
i.e. lifted off the belt (5) pressed thereon. During operation the angular
position of the arm (12), as shown in FIG. 4, leaves a small gap between
the lips (7) in the middle of the belt, through which the trace of lacquer
leaves. During operation the angular position is restrained by suitable
supports, whereby the arms (12) including the lips (7) are pressed from
above in vertical direction on the belt (5). In addition, springs or
pneumatic devices can be provided. For purification of the lips (7), the
arms (12) can be lifted/swung about the vertical axis of the plane. This
is a determined operational advantage particularly with color changes.
For removal of the belt's lacquer trace formed by the lips (7), a removal
pipe (8) is provided, that is elastically (i.e. with a spring device or
pneumatic device, not shown) pressed on the bottom of the belt (5). The
support point of the pipe-edge lies, in this case, precisely behind the
guide roller (6). At this point, a satisfactory attachment of the
pipe-edge to the belt (5) is possible. The complete drainage of the spray
medium trace flows in direction of arrow (60) out of the pipe (8) and can
be collected in a container or reservoir. Thus a recycled use of the
lacquer is possible. The pipe (8) is also able to be lowered in the
vertical direction and, if need be, subsequently removable (thus easily
cleaned). Also other removal devices may be used, e.g. easily cleanable
channels.
In order to reproduce the original viscosity in the solvent lacquer and/or
control the trace formation and respective removal of the excess spray
medium from the belt (5), a preferred embodiment of the invention shows an
arrangement with a device (15) precisely in front of the removal pipe (8)
and respective trace forming lips (7), for application of a additive agent
(preferably a lacquer solvent). This device (15) can expel a continuous
supply capacity (17) for the additive agents and be further distributed by
nozzles (16) over the width of the belt (5). The agents can be applied in
the most desirable manner. For example, a showering or a dripping is
possible.
Preferably the device (15) for application of the additive agents along
with the device for trace-forming lips (7) can form a structural unit, as
shown in FIG. 6 and 7, where both are fastened collectively to the arm
(12). Thus the device (15) always adjusts in definite relative position to
the lips (7) and is collectively removed from the belt.
As is shown in FIG. 6, the specific side (7a) of the lips (7) forms an
acute angle (.alpha.) with the belt surface (5a). This has been a proven
advantage with regard to a good trace formation and a lower material wear
on the belt (5).
In FIGS. 8 and 9 a spray treatment device for objects is characterized, in
which the object (4) is fastened on supports and is not automatically
transported. The supports are formed using thin wires (18) that are
stretched perpendicular over the continuously rotating belt (5). The wires
(18), on which the object (4) rests over the support (20), are held in the
side containers (21), which are fastened to a carriage (22). The carriage
(22) can be adjusted on rails (19) in the belt's direction of transport
thus allowing for conformity to the supported object (4). In principle,
this carriage (18) could have been used for automatic transport of an
object. However, in the preferred embodiment characterized in FIGS. 8 and
9, the carriage is to adjust in the corresponding position along the rails
(19) with the placement of the objects and is then clamped thereon.
The upper-half of the rotating belt (5) runs precisely underneath the
support (18); thus preventing an inadvertent deposit of overspray on the
underside of the objects (4). The thin wires (18) offer little surface for
the spray medium, which can be completely collected by the underlying belt
(5), (unless medium reaches the objects (4). For removal of the excessive
spray medium on the belt (5), a removal system is provided on the vertical
region of the L-shaped belt (5). This consists of a device (15) for the
application of solvents, a t race-forming device in the form of elastic
lips, and finally a removal device (8) in the form of a pipe. The belt is
driven by a motor (23) and a band (24).
As shown in FIG. 8, the removal on the vertical region of the belt (5)
permits an easily accessible arrangement of the individual components.
For manual spraying of objects (4) that rest on the anti-skid support (20)
of the wires (18), a preferred variation of the invention presents the
support (wires 18 including part 20) pivoting with the belt (5) for the
collection of the excessive spray medium around a horizontal axis (26)
revolving on a foundation (27). For high revolution, a pneumatic
control-device 25 can be provided, shown in FIG. 11, consisting of a lift
(H). Through the collective revolution of the support and belt, the
relative position between the object and collection belt remains fixed. In
particular, the belt (5) can be guided precisely below the object's (4).
The high revolution permits a good accessibility to the objects (4)
surface for a manual lacquer application by a spray pistol (not shown).
For the best removal of the spray medium lying on the belt; in addition to
the known trace formation lips and the removal pipe, the belt (5) itself
is also of particular importance. It has already been proven as favorable
if the belt (5) for the collection of the spray medium has a surface
texture (28) i.e. not a completely smooth (FIG. 12). In a preferred
embodiment, the textural base web is covered by a thin coating, preferably
made of plastic. If the belt possess a structural base-line web (29) (e.g.
made of polyester in warp and weft), the surface texture may "shine
through" a thin coating (i.e., 1/10 mm urethane) thereon. This structural
or textural surface has further advantages with regard to the lowest | | |
