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Description  |
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FIELD OF THE INVENTION
The invention relates to a device for the continuous degassing of casting
resin comprising a housing having an inlet and an outlet for guiding
therethrough the casting resin and being connected to a vacuum source. The
invention relates furthermore to a method for the continuous degassing of
casting resin, in which the casting resin is guided under vacuum in a thin
layer over a degassing surface.
BACKGROUND OF THE INVENTION
When manufacturing casting resin parts out of casting resin, it is
necessary to carefully degas each one of the individual casting resin
components prior to their mixing, on the one hand, to avoid defects from
occurring in the finished casting and, on the other hand, to be able to
carry out the casting operation itself without any errors and under the
desired pressure conditions. As it is known from the state of the art, the
casting resin mass is usually mixed out of at least one resin component
and one hardener component, with the components being highly viscous
liquids.
The state of the art consists of both discontinuously and also continuously
working degassing systems. The casting resin or rather the casting resin
components is in both cases guided over a degassing surface with the
desire to apply a thin layer of the respective component to the degassing
surface. The gas components in the casting resin are removed by the vacuum
existing in the housing.
It must be pointed out in this connection that the description hereinafter
refers to the degassing of casting resin to simplify the description. The
man skilled in the art understands that, as a rule, this concerns the
degassing of casting resin components, which have not yet been mixed with
one another, for example a resin component or a hardener component.
The discontinuously working methods use systems which include a storage
container which is so large that, as a rule, a day's charge is received
therein. Degassing takes thereby place in this storage container, from
which the respectively needed volume amount is removed for casting of the
structural elements. The inside of the storage container is under
underpressure during the degassing and during the casting operation.
Circulating devices are usually provided in the storage container, which
devices are used to distribute the casting resin on a large draining or
degassing surface. Sufficient time for the degassing is available with
this procedure during the night hours, during which the casting resin is
not processed.
When production takes place during several shifts, then it is no longer
possible due to the amount of required casting resin, to use the storage
containers simultaneously for degassing. Therefore, additional degassing
containers are utilized, in which the amount of casting resin needed for
production is received and degassed. These degassing containers are mostly
set up at a level above the associated storage container so that the
degassed material can flow into the storage container. From this results
the disadvantage of a high total height. Depending on the shift operation
(two shifts or three shifts), it may be necessary to associate several
degassing containers with a storage container in order to guarantee a
sufficient degassing time for the casting resin. From this results also an
occupation of a large amount of space which in turn leads to high costs
for the system.
Furthermore, there exists the disadvantage with such systems that, with the
apparently advantageous possibility to always add nondegassed material
into the storage container as is continuously being removed, the gas
content in the stored material increases considerably due to the added
nondegassed material, in spite of a continuously running degassing
operation. The demands for quality are as a rule no longer met. A bringing
of nondegassed material together with the already degassed material must,
therefore, be avoided under all circumstances.
It is known in the continuously operating devices to insert in a housing a
horizontally arranged, rotatable plate, onto which the casting resin is
applied. By rotating the plate, the casting resin is guided radially
outwardly so that it can run off downwardly on the inner walls of the
housing. The underpressure in the housing brings about the continuous
degassing. The disadvantage of these devices is that it is not guaranteed
that only the completely degassed product reaches the bottom area of the
housing to be further processed from there. Rather, it is possible, for
example, by moving too much casting resin onto the rotating plate, for
this casting resin to drip downwardly in a nondegassed state. This would
result in a mixed product which is not sufficiently degassed.
A cascade degassing is provided in a further device known from the state of
the art, in which the casting resin runs cascade-like over several
degassing surfaces arranged in the housing. This theoretically enables a
fine distribution of the casting resin and a long treatment time. The
disadvantage is that it cannot be assured, nor monitored, that the casting
resin is distributed in an even layer on the degassing surfaces. Rather a
so-called "stream formation" occurs often, during which the casting resin
flows in large volume streams downwardly at certain points on the
degassing surface. Only an insufficient degassing or none at all takes
place at these points for understandable reasons.
SUMMARY OF THE INVENTION
The basic purpose of the invention is to provide a device and a method for
the continuous degassing of casting resin, which with a simple design and
effective operation guarantee a good degassing of the casting resin and
have a high degree of operating safety.
With respect to the device, the purpose is attained by providing several
areas in the housing, through which areas the casting resin is
successively guided for facilitating a step-like degassing, with means
being associated with each area for applying the casting resin to a
degassing surface associated with the area and means for transferring the
casting resin into the next area.
The device of the invention is distinguished by a number of significant
advantages. Since several areas are provided in the housing, which areas
are separated from one another, a step-like degassing is possible during a
continuous flow of the casting resin through the housing, during which
degassing the content of gas in the casting resin is constantly reduced
from one step to the other. It is of a particularly great advantage that
always only predegassed material can be guided from one area to the other
so that an unintended flow through the device, as this is known from the
state of the art, is entirely impossible. Thus, a large degassing surface
can, according to the invention, be available through simple means so that
the device having a compact design operates with a high efficiency and
high operating safety.
A particularly favorable embodiment of the invention provides that the
housing is constructed as an upstanding cylinder having an upper inlet and
a lower outlet and the areas are formed by several pistons each sealingly
arranged in the housing, which pistons each have an opening for the
casting resin and are movable in a longitudinal direction of the housing.
Thus, the individual pistons form, according to the invention, separating
elements which define the areas, with the respectively degassed casting
resin being able to accumulate on the respective surface of the piston and
be guided through the opening into the next area. Since the individual
pistons can be moved up and down in the longitudinal direction of the
cylinder, a very high degassing surface is created, with the up and down
movement of the piston resulting in an even application of the casting
resin on the surface and in a removal from the surface. The described
embodiment of the device thus guarantees, with the simplest construction
and space-saving design, a very high efficiency and a good degassing of
the casting resin. By suitably selecting the amount of casting resin to be
guided through the device, the stroke speed of the piston and the opening
into the piston, the degassing performance is variable within a wide scope
and can be adapted to the respective conditions for use.
The pistons are advantageously connected with one another by means of a
common piston rod in order to guarantee a synchronous movement of the
pistons and to keep the respective volume in the individual areas
unchanged.
In order to guarantee an even application or rather an even removal of the
casting resin to or from the inner wall of the housing (degassing
surface), the periphery of the pistons are designed such that they form
together with the degassing surface of the housing an upwardly open
trough.
It is furthermore advantageous to arrange the openings of the pistons so
that a desired flow through the individual areas is achieved.
It is furthermore particularly advantageous, according to the invention,
when the container has at least one level sensor in the collecting area.
The level sensor determines whether a sufficient amount of degassed
material is in the last area, that is, in the collecting area of the
container in order to be able to carry out the respectively next following
casting operation. Thus, it is assured that sufficient casting resin
volume can be supplied to the flow mixer arranged after the device of the
invention.
A further, particularly favorable, embodiment is the provision of a return
pipeline extending from the outlet region of the container to an area of
the container and/or storage container upstream of the outlet. This
measure makes it possible for the material accumulated in the collecting
area to be fed, for example through valves which are provided in the
pump-out pipeline, selectively to one of the degassing areas or the
storage container. This makes it possible for material accumulated in the
bottom of the housing to be subjected to a further degassing process
during the time periods in which no casting is taking place, or the device
is emptied during shutdown times.
Since a pump is needed to supply the degassed casting resin to the flow
mixer, it can be particularly advantageous when the piston rod connecting
the individual pistons carries a pump piston at its lower end, which pump
piston can be moved into a pump cylinder fastened on the housing. Thus,
the movement of the piston in the cylinder can be connected with the
casting operation, which means with the operation of the pump.
The device can advantageously also be operated such that the movement of
the pistons for the purpose of effecting degassing, without pump feeding,
can be carried out in an upper stroke area, while at least a lower stroke
area is utilized for the simultaneous degassing and pump feeding.
The housing is, in an alternative embodiment of the invention, constructed
as an upstanding cylinder having an upper inlet and a lower outlet, with
the areas being formed by a helical flight rotatably supported in the
housing, an outer contour of the helical flight being sealingly guided on
the inner surface of the housing. The helical flight can be rotated
preferably in the same direction, in an opposite direction or alternately
with respect to the flow direction of the casting resin. It is hereby
assured that the casting resin material is, for a sufficient time period
in the respective "degassing area". The rotation of the helical flight
assures thereby that the casting resin remains on the degassing surface
formed by both the inner wall of the housing and also by the helical
flight surface. The direction of rotation of the helical flight is adapted
in a preferred manner to the viscosity of the casting resin material in
order to be able to adhere to a sufficient degassing time.
A further, also very favorable, embodiment of the invention provides that
the housing is constructed as a horizontal cylinder with an inlet and
outlet on the bottom side thereof, with the areas being formed by several
vertically upright partitions which extend over a partial area of the
height of the cylinder. One plate, which is rotatable about a horizontal
axis and is guided with play in the area, is associated with each area.
Furthermore, a stripping means, which is secured to the housing rests
against the respectively adjacent plate, is provided at least at the upper
edge of each partition, which stripping means removes during rotation of
the plate therepast the accumulated casting resin material off from the
respective plate area and transfers it to the next area. It is understood
that the stripping means, when the partitions are constructed all together
essentially semicircularly, is arranged only on one half of the upper edge
of the partition. The rotating vertically upright plate becomes immersed
in this embodiment of the device in the area and is wetted with the
casting resin material. This partial area of the plate leaves, during the
next following rotation, the area coated with the casting resin so that
the casting resin coat is exposed to the influence of the vacuum or
underpressure. The degassing hereby takes place. During a further rotation
of the plate, this partial area of the casting resin reaches the stripping
means and is transferred into the next area. The areas are thus
distinguished with respect to their content such that from the inlet side
of the housing toward the outlet side there exists in each case a smaller
amount of gas in the material of each area. The dimensions of the plates
and the speed of rotation can be adapted in the simplest manner to the
respective conditions for use, in particular to the type of the material.
The plates are preferably arranged on a common axis of rotation.
Brush or comb-like stripping means are utilized in a further advantageous
embodiment, which stripping means have the purpose of not only applying
the material to be degassed to the degassing surfaces, but also to
continuously slice or cleave through this material and to provide the
material with a profile so that the gases contained in lower layers reach
the surface quicker and thus the degassing operation as a whole is
accelerated.
The housing is in a further advantageous embodiment of the invention
constructed as a horizontal or inclined cylinder, with a rotatable drum
being arranged in this housing. One or several helical ribbons are mounted
on the inner side of the drum, namely, on the degassing surface thereof.
The helical ribbons assure during a rotation of the drum, on the one hand,
a transport of the material from the inlet to the outlet and, on the other
hand, significantly enlarge the available degassing surface of the drum.
Such a device can also advantageously be driven in the "reciprocating
rolling method" which is particularly advantageous for a material with
sedimentizing fillers.
It can be favorable in all described embodiments when the wall of the
housing and/or the degassing surfaces are constructed as heat exchanger
surfaces for heating and cooling in order, for example, to heat in this
manner the casting resin in order to, on the one hand, improve the flow
characteristics and, on the other hand, be able to more effectively carry
out the degassing operation. It is also possible to heat the supply
container from which the casting resin is guided into the housing, and/or
to provide it with an agitating device.
Regarding the method, the purpose is attained according to the invention by
the casting resin being treated in steps in successive, separate degassing
steps. Thus, it is assured that a reliable degassing takes place. In order
to guarantee a fine distribution of the casting resin on a surface as
large as possible and in order to be able, on the other hand, to carry out
after a sufficient degassing time a transfer into the next area,
distribution and transfer means of different constructions, like pistons,
screws, plates, etc, which also partly themselves form the degassing
surfaces, are provided.
The invention thus assures that the casting resin is applied to a pregiven
degassing surface, remains there during a pregiven, adjustable degassing
time, and is thereafter removed from this surface and guided to the next
degassing step.
The degassing device of the invention can in the same manner also be
utilized for mixing of various casting resin components so that, if
necessary, also a finished casting resin mixture can be obtained. A
homogeneous mixing and degassing occurs then simultaneously.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be described hereinafter in connection with exemplary
embodiments and the drawings, in which:
FIG. 1 is a schematic view of a degassing system using the device of the
invention,
FIG. 2 is a schematic partially cross-sectioned view of a first exemplary
embodiment of the device of the invention,
FIG. 2.1 is a view of a device of the invention corresponding with FIG. 2,
FIG. 3 is a view, similar to FIG. 2, of a further exemplary embodiment of
the device of the invention,
FIG. 4 is a schematic partially cross-sectioned side view of a further
exemplary embodiment of the device of the invention,
FIG. 5 is an also partially cross-sectioned front view of the device
illustrated in FIG. 4,
FIG. 6 is a partially cross-sectioned side view of a further exemplary
embodiment according to the invention,
FIG. 7 is a partially cross-sectioned front view of the exemplary
embodiment according to FIG. 6,
FIG. 8 is a schematic partially cross-sectioned side view of a further
exemplary embodiment,
FIG. 9 is a partially cross-sectioned front view of the exemplary
embodiment according to FIG. 8, and
FIG. 10 is a schematic side view of a further exemplary embodiment with
comb-like or brushlike stripping means,
FIG. 11 is a cross-sectioned view of the exemplary embodiment according to
FIG. 10,
FIG. 12 shows a further exemplary embodiment according to the invention
having a rotatable device with helical ribbons mounted on the degassing
surfaces,
FIG. 13 is a cross-sectional view of the exemplary embodiment according to
FIG. 12,
FIG. 14 is a schematic side view of a modification to the embodiment of
FIGS. 10 and 11, and
FIG. 15 is a cross-sectional view of the exemplary embodiment of FIG. 14.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows a casting resin processing system which enables the degassing
and mixing of two components. The system includes storage containers 19
and 20, with the left storage container 19, for example, being provided
for a watery material, and the right storage container 20 being provided
with an agitator and a heater in order to agitate a highly viscous
material and/or a material containing fillers. The system includes
furthermore two housings 1 of the degassing devices to be described
hereinafter. The housings 1 are arranged parallel to one another in FIG. 1
and are each connected to the storage containers 19, 20 through a
pipeline. A flow controller 21 is arranged in each of the pipelines.
Furthermore, the inner chambers of the housing 1 are connected to a vacuum
source 4. A heater 23 is associated with each housing 1. A pump device 22
for the synchronous dosing of the material volume to be removed in each
case and for supplying same to a flow mixer 24 is provided at the outlet
area of each housing 1. A casting valve 25 is arranged at the outlet of
the flow mixer 24 in order to feed the mixed casting resin mass to a mold
(not illustrated).
FIG. 2 shows a preferred exemplary embodiment of the device of the
invention which, regarding the schematic illustration, corresponds with
the left half of FIG. 1. The casting resin material from the storage
container 19 is fed through the flow controller 21 and a throttle 26
arranged after the flow controller to an upper inlet 2 of the housing 1.
The material can be discharged through a lower outlet 3 and can be fed to
the flow mixer 24.
A piston rod 8, in the exemplary embodiment illustrated in FIG. 2, is
centrally arranged in the vertically arranged, upstanding cylinder of the
housing 1. The piston rod can be moved up and down in vertical direction
by a drive 27. A guide plate 41 for the piston rod and the pump piston 12
is arranged at the lower end of the piston rod 8, which guide plate has
openings 42 through which the casting resin flows into the pump cylinder
13. This guide plate has at the same time the task of mixing the already
degassed casting resin and preventing a settling of solid materials
possibly contained in the casting resin. Several pistons 6 are fastened to
the piston rod 8, all together four such pistons in the illustrated
exemplary embodiment. The left half of FIG. 2 shows a state in which the
pistons 6 and the piston rod 8 are moved downwardly, while the right half
shows a state in which the pistons 6 and the piston rod 8 are in an upper
state.
The pistons 6 are each designed as circular pistons and are supported
closely on the inner wall of the housing 1. The pistons 6 form together
with the degassing surface 40 an upwardly open trough 9. Furthermore, each
piston 6 has at least one opening 7 in order to guide casting resin
material from the area 5 formed between each two pistons into the next
following area.
A level sensor 10 is furthermore arranged at the bottom end area of the
housing 1, which level sensor is operatively connected to a control device
(not shown) to which is also connected the drive 27 and the flow
controller 21. A check valve 29 is furthermore provided in the outlet
pipeline of the housing 1, which check valve is followed by a three-way
valve 28, which is connected to a return pipeline 11 and a pipeline 30 to
the flow mixer 24.
The operation of the device illustrated in FIG. 2 will be described
hereinafter:
Casting resin material is guided from the storage container 19 through the
flow controller 21 and the throttle 26 into the upper inlet 2 of the
housing 1. A first area 5 is formed above the uppermost piston 6 in order
to receive the material which has not yet been degassed. During a downward
movement of the piston 6, the material can accumulate above the piston 6,
it is in particular introduced into the trough 9. During an upward
movement of the piston 6, the material is wiped off the wall of the
housing 1 and is collected above the piston 6, for example, in the trough
9. The material in the trough 9 wets during a downwardly directed movement
of the piston 6 the housing wall 1 and can in this manner be degassed by
the vacuum applied by the vacuum source 4. The described operating steps
are repeated cyclically. After a predetermined volume of material has
accumulated above the uppermost piston 6, the material can flow through
the opening 7 as this is shown in FIG. 2.1. Thus the material reaches the
surface of the next following piston 6, with the degassing operation being
repeated cyclically in an analogous manner. Thus the material flows
through the individual areas 5 after a presettable duration and
accumulates in the bottom area of the housing 1. The level of the
material, which is now completely degassed, is determined by the level
sensor 10. A transfer to the flow mixer 24 does not occur when the volume
of material is too low. The material accumulated in the bottom area of the
housing 1 can be recirculated through the return pipeline 12 and the
three-way valve 28 in order to continue to keep this material under
degassing conditions when no casting operation takes place.
The lower area of the piston rod 8 is designed as a pump piston 12 which
can be moved into a pump cylinder 13 of the housing 1. Thus the drive 27
pumps off the degassed material. If no transfer into the flow mixer 24 is
desired, the material is pumped through the return pipeline 11 into one of
the areas 5 or into the storage container 19, 20.
The wall of the housing 1 can be designed as a heatable or coolable double
wall.
FIG. 3 shows a further exemplary embodiment which differs from the
exemplary embodiment according to FIG. 2 in the following areas. Identical
characteristics are not described. A drive 31 is provided at the upper
area of the housing 1 in the exemplary embodiment illustrated in FIG. 3,
which drive initiates the rotation of a shaft 32 on which a helical flight
14 is fastened. The helical flight 14 rests with its outer contour
sealingly against the inner wall of the housing 1. The drive 31 rotates
the helical flight 14 in the same direction, in opposite direction or
alternately with respect to the flow direction of the casting resin
material. This results in an even distribution of the casting resin
material both on the inner wall of the housing 1 and also on the surface
of the helical flight 14. By rotating the helical flight, which can also
be alternately, the casting resin material deposited on the housing wall
is cyclically removed or applied so that an effect occurs which is
analogous to the operation of the device according to FIG. 2.
FIGS. 4 and 5 show a further embodiment of the device of the invention. It
includes a cylindrical, horizontally oriented housing 1 in which an axle
of rotation 18 is centrically rotatably supported by a drive 33. Circular
plates 16, which are parallel to one another, are fastened on the axle of
rotation 18. The housing 1 has an inlet 2 at one bottom end and an outlet
3 at an opposite bottom end.
As is particularly shown in FIG. 4, several vertical partitions 15 extend
in the lower half of the housing 1. The partitions end below the axis 18
so that individual areas 5 are formed. A stripping means 17 is arranged on
one half of the upper edge of each partition 15, which stripping means
rests against or slidingly engages the respective plate 16. By rotating
the plate 16 in clockwise direction (see FIG. 5), the material which,
during the immersion of the plate 16 into the area 5, accumulates on same
is transferred into the upper chamber of the housing 1 where it is exposed
to the action of the vacuum source 4. A thin film of material is thereby
arranged on the plates 16 so that degassing can take place under defined
conditions. The material adhering to one side of the plate (right side
according to FIG. 4) is, during a rotation of the plates 16, removed by
the stripping means 17 and is transferred into the next following area 5
or rather into an outlet section 34 located adjacent the outlet 3. Thus a
continuous degassing of the material takes place, with the material being
further degassed in each following area.
The exemplary embodiment according to FIGS. 6 and 7 is designed according
to the embodiment of FIG. 4, with the same parts having the same reference
numerals. The difference between this exemplary embodiment and the one
according to FIGS. 4 and 5 is that separate stationary areas 5 are here
not constructed but instead these stationary areas 5, corresponding with
the exemplary embodiment according to FIG. 3, are formed by a rotating
screw, with the screw being guided sealingly on the inner walls of the
device 1 so that the casting resin entering through the inlet 2 cannot
flow directly to the outlet 3. A suction channel 38 is arranged above the
screw, as this is clearly shown in FIG. 7. The individual areas inside the
device 1 are evacuated through this suction channel 38. The device can be
operated either exclusively in conveying direction, namely, when a
sufficient number of areas are created which are needed for the degassing.
If one wants to make the device shorter, the screw can be operated with
the reciprocating rolling method, namely, the screw oscillates, with the
zero point of the oscillation movement moving constantly in the exemplary
embodiment corresponding with the solid arrow in FIG. 7 so that the
casting resin contained in the areas is slowly transported from the inlet
to the outlet.
The exemplary embodiment illustrated in FIGS. 8 and 9 corresponds
essentially with the exemplary embodiment according to FIGS. 6 and 7, with
the helical flights 14 having been replaced by individual plates 16 which
also move sealingly along the inner walls of the device 1. In order to
achieve here a movement of the casting resin from the inlet 2 to the
outlet 3, openings 37 are arranged in the plates 16. A suction channel 38
covering all areas 5 is used to facilitate the evacuation. This device can
either operate rotatingly or, however, it can be moved in the
reciprocating rolling method, with the openings 37 immersing only at times
into the casting resin and permitting the further transport of the casting
resin to the outlet 3.
The degassing device in the exemplary embodiment according to FIGS. 10 and
11 consists of a horizontally arranged cylinder, the inner wall of which
cylinder forms the degassing surface 40. This cylinder can, in contrast to
the exemplary embodiment, also be arranged inclined or even vertically,
with the inclination being able to be varied also in dependency of the
viscosity of the medium to be degassed. The same parts are identified with
the same reference numerals in this exemplary embodiment. The difference
between this exemplary embodiment and the exemplary embodiments discussed
above is that stripping means like brushes or combs are arranged rotatably
inside of the housing 1, with three stripping means 42 offset each at
120.degree. to one another being each arranged in one plane as shown in
FIG. 11. These brushes or combs 42 slice or cleave through the material to
be degassed and supplied through the inlet 2 in order to provide the
material with a profile and constantly create new surfaces which are
significantly larger than the degassing surface 40. With this a very
intensive and most of all quick degassing of the material is possible.
Moldings 140 (FIGS. 14 and 15) can be arranged between the individual
stripping means 42 so that also the duration in the area of the individual
stripping means can be controlled. These brush or comb-like stripping
means can also be utilized in the other devices.
The moldings 140 are oriented in pairs which straddle each of the comb-like
stripping means 42. For example, moldings 140A and 140B straddle the brush
or comb 42A, moldings 140B and 140C straddle the brush or comb 42B, etc.
Further, the distal ends of each of the brushes or combs 42 are oriented
in planes which are angled slightly to the plane of rotation so that the
casting resin will be urged rightwardly toward each downstream molding as
they pass through the resin. As shown in FIG. 15, the moldings 140 each
include upper and lower spaced apart arcuate segments. As the distal ends
of the brushes or combs 42 sequentially move past the downstream molding
140, particularly, the upper end of the lower segment in the direction of
movement of the brushes or combs 42, resin will be urged past the molding
into the next downstream section oriented between the next pair of spaced
apart moldings (or partitions) and as represented by the arrows in FIG.
14.
In the alternative, and instead of orienting the distal ends of the brushes
or combs 42 in a plane angled slightly to the plane of rotation, the
cylinder of the housing 1 can be elevated at the left resin input end
above the right resin outlet end. The free flow of resin will be stopped
by the moldings or partitions 140. In every instance, the depth of the
resin is less than the height of the moldings or partitions 140.
The exemplary embodiment according to FIGS. 12 and 13 represents an
alternative according to the exemplary embodiment of FIGS. 4 to 7.
Identical parts have the same reference numerals. A drum 43 is rotatably
arranged in the evacuatable housing 1 in this embodiment, with same being
able to be horizontally arranged or inclined. A helical ribbon 44 is
mounted inside of the drum on the degassing surface 40, which helical
ribbon contributes during a rotation of the drum to the distribution of
the material supplied through the inlet 2. With this the degassing surface
is, on the one hand, enlarged and, on the other hand, the degassed
material is moved to the outlet 3. The speed and also the direction of
rotation can be changed in dependency of the degassing task. In certain
cases it may also be advisable to rotate the drum in the "reciprocating
rolling method". This is particularly advantageous when a material which
is to be degassed is used which has a sedimentating filler. The
sedimentation direction for the filler particles is alternately reversed
by the alternating rotation of the drum so that a separation is
counteracted.
The invention is not to be limited to the illustrated exemplary embodiment,
rather many possibilities for modifications exist within the scope of the
invention.
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