Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
2~7474g
- APPLICATION UNIT FOR THE DIRECT OR INDIRECT APPLICATION
OF A LIQUID OR PASTY MEDIUM ONTO A MOVING MATERIAL WEB
The invention relates to application units for the direct or
indirect application of a liquid or pasty medium onto a
moving material web according to the preambles of the
parallel independent claims 1, 12 and 20.
Such known application units are specifically equipped for
their respectively intended use. On the one hand, free jet
nozzle application units are built in which the liquid or
pasty medium is applied via a dosing gap as a free jet. In
direct application, the free jet impinges upon the moving
- material web, while the free jet in indirect application is
applied onto an application roll, the liquid or pasty medium
being transferred from the surface thereof onto the moving
material web. On the other hand, application units are built
with an application chamber in which the liquid or pasty
medium is applied from a chamber by means of a dosing member,
for example a wiper or doctor blade member. In direct
application, the medium is directly applied onto the moving
material web, while the medium in indirect application is
initially applied onto an application roll and transferred
from its surface onto the moving material web.
A commonly known application unit with a free jet nozzle
dosing gap is described, for examplel in the Canadian patent
application CA-A-2 101 358. Such an application unit with a
free jet nozzle can be operated in a relatively uncomplicated
manner, it does not have any real wearing parts and is
t
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therefore relatively free of maintenance. It is only
suitable for speeds of passage up to approximately 1500 m/min
but has a low tear frequency and is particularly suitable for
tension-sensitive, i.e. thin papers.
A commonly known application unit with an application chamber
is described, for example, in the European patent application
EP-A-0 496 946. Such an application unit with an application
chamber is suitable for higher speeds of passage (> 1500
m/min.) and effects a greater penetration depth on account of
the pressure in the application chamber. Additionally, such
an application unit is suitable for low coating weights and
simultaneously enables a clean coverage.
Depending on the type of application, the respectively
suitable application units must be built into a coating
machine. Should a change in the intended use of the coating
machine require the use of a different application unit, the
entire application unit must be exchanged. Such a complete
conversion is very time-consuming and complicated.
The invention is therefore based on the technical problem of
providing a new type of application unit which permits quick
and easy conversion.
This technical problem is solved in accordance with the
invention by an application unit comprising the features of
claim 1, by an application unit comprising the features of
the parallel independent claim 12 and by an application unit
comprising the features of the parallel independent claim 20.
The invention is based on the concept of p~oviding an
application unit which in the case of conversion must not be
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-
completely exchanged, for example together with the support
beam, the distribution means for the liquid or pasty medium,
the connecting and adjusting means and other devices. In the
inventive solution according to the parallel independent
claims 1, 12 and 20, only those members are respectively
exchanged or added or removed which directly serve for the
application of the liquid or pasty medium. Thus, an
application unit equipped according to the invention includes
a basic structural group which remains in use both in
connection with a free jet nozzle arrangement as well as a
blade~member application chamber arrangement. This basic
structural group comprises the supporting beam including the
distribution means for the liquid or pasty medium, the
connecting and adjusting means required for these previously
mentioned members as well as the forward and rearward walls
for formation of the feed gap including the feed channels for
the liquid or pasty medium supplied from the distribution
means into the feed gap.
According to the inventive solution of claim 1, the members
directly serving for the application of the liquid or pasty
medium are mountable on the previously described basic
structural group. These members directly serving for the
application of the medium on the one hand involve attachable
members for the formation of an application chamber, for
example a blade support with a doctor blade as well as a
damming strip and, on the other hand, attachable members
which border a dosing gap effective as a free jet nozzle.
The basic structural group therefore serves as a platform
upon which either the attachable members for formation of an
application chamber or the attachable members for formation
of a free jet nozzle dosing gap can be placed in a modular
form. Thus, based on the basic structural group, it is
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possible to alternatively realize the application chamber
variant or the free jet nozzle variant for the application
unit.
The attachable members belonging to the application chamber
variant and the attachable members belonging to the free jet
nozzle variant can in this case respectively be attached as a
completed module and be mutually exchanged, or can
respectively be mounted in the form of individual attachable
members. In the case of multi-part individual structural
members, common attachable members can advantageously be
formed which find use both in the application chamber variant
and the free jet nozzle variant in the same structural
position. Such a common attachable member which, for
example, forms a part of the free jet nozzle dosing gap in
the one structural variant and a part of the application
chamber in the other variant can also be securely fastened to
the basic structural group and possibly be formed integrally
with this.
In the inventive solutions according to the parallel
independent claims 12 and 20, the members serving in the
second application unit variant which directly serve for the
application of the liquid or pasty medium can be placed on an
application unit which is already capable of operation by
itself in the first application unit variant. Therefore, in
accordance with the invention, an application unit capable of
operation which consists of a basic structural group and of
an application chamber arrangement or of a basic structural
group and a free jet nozzle arrangement is taken as a basis
which can be converted into the respective application unit
variant in that the members in this other variant serving
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directly for the application of the liquid or pasty medium
can be additionally mounted to the existing application unit.
Thus, when an application unit is taken as a basis which
consists of a basic structural group with an application
chamber, the conversion into a free jet nozzle application
unit ensues by means of mounting appropriate free jet nozzle
attachable members in the region of the structural members
which form the application chamber. In the case of an
application chamber with a blade support and a ~mm;ng strip,
for example, lip members, for example, are attached to the
doctor blade body and the ~mm;ng strip in order to form a
dosing gap which is effective as a free jet nozzle.
If an application unit which consists of a basic structural
group and a free jet nozzle arrangement forms a basis, in an
analogous manner to the previously described case, the
members serving directly for the application of the liquid or
pasty medium in an application chamber application unit are
mounted in the area of the free jet nozzle arrangement.
Thus, for example, if the free jet nozzle dosing gap is
formed by two lip members, an attachable member with a blade
support and a doctor blade member as well as an attachable
member for formation of a damming strip are mounted, for
example, on the lip members in order to obtain an application
chamber.
Therefore, in both previously described inventive solutions,
the basic structural group as well as the members of the one
application unit variant taken as a basis which serve for the
direct application of the liquid or pasty medium are retained
in each conversion variant. The conversion to the second
application unit variant ensues by attaching the members
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serving in the second variant directly for the application of
the liquid or pasty medium, and the reconversion to the first
variant ensues by way of removal of these members. The
application chamber arrangement or free jet nozzle
arrangement associated with the respective basic application
unit can be connected either completely releasably or at
least partially integrally with the basic structural group.
Only the releasability of those attachable members which
determine the additional application unit variant placed on
the basic application unit is initially necessary.
In the inventive solutions according to the parallel
independent claims 1, 12 and 20 for a conversion of an
application chamber application unit to a free jet nozzle
application unit and vice versa, only the respectively
specific attachable members which are easier and quicker to
handle must be attached or removed and not, as was previously
the case, the complete application unit with the support
beam, the distribution means, the adjusting means etc. As a
result of this, a considerable time-saving alteration of the
application mode results in accordance with the invention for
a coating machine, which leads to an economical and varied
application of the coating machine.
In accordance with the invention, the attachable members can
be formed in such a manner to realize an application chamber
arrangement or a free jet nozzle arrangement that in the case
of conversion from the one to the other variant, a change in
the direction of rotation of the associated counter-roll or
application roll ensues. Naturally, the attachable members
can also be designed in such a manner that in the both
conversion variants, the rotational direction of the
associated roll which acts in direct application as a
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counter-roll for the passing material web and, in indirect
application, as the application roll can be maintained.
However, a design of the attachable members in such a manner
that the application direction with respect to the associated
roll changes and, thus, the rotational direction of the roll
can also be advantageous to the extent that the operation
means, i.e. especially the adjusting means for the
application means serving for the direct application of the
liquid or pasty medium, for example, dosing gap or blade
support adjusting means, can be maintained in both
application variants on the same operational side of the
coating machine.
Advantageous embodiments of the inventive solution according
to claim 1 are explained in the following.
Depending on the purposefully appearing structural design,
the attachable members for the application chamber or the
free jet nozzle dosing gap can be integral or of multiple
parts. In the design of multi-part attachable members, it
can be useful that a common attachable member is designed in
such a manner that it is capable of being used in the same
attached position both in the case of attachment of the
application chamber as well as in the case of attachment of
the free jet nozzle dosing gap. Such a common attachable
member can be releasably connected with the basic structural
group, but it can also be connected in a fixed manner or even
integrally with the basic structural group. If such a common
attachable member can be formed, the number of attachable
members which must be converted upon conversion from the one
to the other application unit variant is correspondingly
reduced and the conversion therefore takes place in an easier
and quicker manner.
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Usefully, the attachable members for formation of the
application chamber comprise a blade support with a blade
member and a ~mm;ng strip. Additionally, the structural
members for formation of an application chamber usefully
comprise an overflow means in the area of the damming strip.
Preferably, the overflow means includes an overflow
collecting and discharging means which adjoins the overflow
surface.
The structural members for a free jet nozzle dosing gap
usefully have an essentially strip- or lip-shaped form.
In an advantageous embodiment, the attachable members for a
free jet nozzle dosing gap are designed in such a manner that
a concave free deflection surface for the liquid or pasty
medium is adjoined on the one side to the free end of the
dosing gap bordered on both sides by wall surfaces. As a
result of such a free deflection or guiding surface, the free
jet of the liquid or pasty medium can be guided in an
advantageous manner in the desired direction.
A further useful embodiment of the invention consists in
designing the attachable members for formation of the free
jet nozzle dosing gap in such a manner that the dosing gap
forms an approximately right-angle with the feed gap for the
liquid or pasty medium.
The forward and rear walls of the basic structural group
which can be also called as the outer wall and the inner wall
can be designed in the most varied manner.
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However, it is useful in this case to design the areas of the
forward and rear walls in such a manner that the
corresponding attachable members can be simply and precisely
placed and attached. In the case that the attachable members
are to be placed on removable parts in the area of the
forward and rear walls, it can be useful to form such parts
integrally with parts in the area of the forward and rear
walls. In other words, the separation plane between the
basic structural group and the members attached thereto can
also inventively extend within the forward and rearward wall
areas for formation of an application chamber arrangement or
a free jet nozzle arrangement. Parts of the forward and
rearward walls as well as the area bordering these can
therefore also be associatéd with the attachable members and
thus be exchanged upon conversion from the one variant to the
other.
As already previously described in connection with a common
attachable member, the separation plane between the basic
structural group and the attachable members for forming the
application chamber arrangement or the free jet nozzle
arrangement can alternatively be located such that structural
members which are placed on the area of the forward and/or
rear walls or integrally continue at this position always
remain upon conversion and are therefore associated with the
basic structural group. For example, a section adjoining the
rear wall area or a member placed at this location can be
retained for both conversion variants in that it forms a part
of the free jet nozzle dosing gap in the one instance and a
part of the application chamber in the other.
Such designs in which areas of the forward and/or rear wall
as well as partial areas adjoining these are formed by
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attachable members and removed from or mounted to this also
belong to the inventive solution according to claim 1. Those
designs also belong to the inventive solution according to
claim 1 in which partial areas going beyond the area of the
forward or rear walls or the members placed on this are
retained upon conversion, i.e. those in which the basic
structural group extends beyond the forward or rear wall
area.
Usefully, the application unit is provided with an advancing
and/or tilting means so that changes in spacings, which
result from the attachment of the different attachable
members for the two application unit variants with respect to
the associated counter-roll or application roll, can be
compensated and the angular position of the application
chamber arrangement for the fine jet nozzle arrangement with
respect to the counter-roll or the application roll can be
precisely adjusted according to the respective circumstances.
In the following, advantageous embodiments of the inventive
solution according to the parallel independent claim 12 are
explained.
Depending on the constructive design which appears to be
expedient, the lip members which form the free jet nozzle can
be connected either securely, possibly integrally, or at
least partially releasably with the area of the forward or
rear wall of the basic structural unit.
The attachable members for forming an application chamber are
designed in the form of one or several parts. Preferably,
the attachable members for forming the application chamber
comprise a blade support with a blade member and a damming
217474~
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strip. In one expedient embodiment, an overflow means is
formed in the region of the damming strip. The overflow
means usefully has an excess collecting and discharging means
which joins the overflow surface. A further embodiment
consists in forming the blade support of several parts.
Preferably, the application unit is equipped with an
advancing and/or tilting means. The advancing enables a
spatial displacement of the application unit, while the
tilting means makes it possible to change the angular
position of the application unit. Thus, changes in distances
to the counter-roll or the application roll which result on
account of the different attachable members upon conversion
from the one application unit variant to the other can be
compensated. Further, the angular position of the
application chamber arrangement or of the free jet nozzle
arrangement can be adjusted precisely according to the
respective circumstances.
In the following, advantageous embodiments of the inventive
solution according to the parallel independent claim 20 are
explained.
Depending on the constructive design which appears expedient,
the members forming the application chamber can be connected
securely, possibly integrally or at least partially
releasably with the area of the forward and rear walls.
Preferably, the attachable members for forming the free jet
nozzle dosing gap have an essentially strip-like or lip-like
form. In this case, it ls particularly advantageous when the
attachable members for forming the free jet nozzle dosing gap
are designed in such a manner that a concave free deflection
2174749
12
surface adjoins on one side with the free end of the dosing
gap bordered on both sides by wall surfaces. The free jet of
liquid or pasty medium can be guided in the desired direction
by means of such a concave deflection or guiding surface.
Depending on structural expediency, the attachable members
for forming the free jet nozzle dosing gap are formed
respectively of one or several parts. The application unit
is preferably equipped with an advancing and/or tilting means
in order to be able to adapt the spacing of the application
unit to the counter-roll or the application roll as well as
the angular position of the application unit with respect to
the counter-roll or the application roll for both conversion
variants. On the one hand, such adaptations are dependent on
the different structural dimensions of the attachable members
in both variants and on the different principles of operation
when applying the liquid or pasty medium by means of an
application chamber or a free jet nozzle.
In the inventive solutions according to the parallel
independent claims 1, 12 and 20, the securing of the
attachable members can naturally ensue in the most varied
ways and depends on the respective structural circumstances.
Equally, the structural design of the attachable members
depends on the respectively intended use.
In the following, exemplary embodiments of the invention are
now described in more detail with reference to the enclosed
drawings.
ig. 1 schematically shows a first exemplary embodiment of
an application unit according to the invention with
a basic structural group and attachable members
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mounted thereon for formation of an application
means in the form of an application chamber;
ig. 2 schematically shows the first exemplary embodiment
of the inventive application unit with the basic
structural group according to Fig. 1 and attachable
members mounted thereon for the formation of an
application means in the form of a free jet nozzle;
ig. 3 schematically shows a second exemplary embodiment
of the application unit according to the invention
with a basic structural group and attachable
members mounted thereon for the formation of an
application means in the form of an application
chamber;
ig. 4 schematically shows the second exemplary embodiment
of the inventive application unit with the basic
structural group according to Fig. 3 and attachable
members mounted thereon for the formation of an
application means in the form of a free jet nozzle;
ig. 5 schematically shows a third exemplary embodiment of
the application unit according to the invention
with a basic structural group and attachable
members mounted thereon for the formation of an
application means in the form of an application
chamber;
ig. 6 schematically shows the third exemplary embodiment
of the inventive application unit with the basic
structural group according to Fig. 5 and attachable
21747g9
14
members mounted thereon for the formation of an
application means in the form of a free jet nozzle;
ig. 7 schematically shows a fourth exemplary embodiment
of the application unit according to the invention
with a basic structural group and attachable
members mounted thereon for the formation of an
application means in the form of a free jet nozzle;
ig. 8 schematically shows the fourth exemplary embodiment
of the inventive application unit with the basic
structural group according to Fig. 7 and attachable
members mounted thereon for the formation of an
application means in the form of an application
chamber;
ig. 9 schematically shows a fifth exemplary embodiment of
the application unit according to the invention
which is provided in terms of its basic structure
with an application means in the form of a free jet
nozzle and application members mounted thereon for
the formation of an application means in the form
an application chamber;
ig. 10 schematically shows a sixth exemplary embodiment of
the application unit according to the invention
with an application means in the form of an
application chamber;
ig. 11 shows the sixth exemplary embodiment of the
application unit according to the invention with
the basic structure according to Fig. 10 and
attachable members mounted thereon for the
i
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formation of an application means in the form of a
free jet nozzle.
It is known that application units are used for the direct or
indirect application of a liquid or pasty medium onto a
moving material web, such as paper or board. In the case of
indirect application, the liquid or pasty medium is applied
by the application unit with a predetermined layer thickness
onto the surface of a roll 1 which transfers the layer onto
the moving material web in a subsequent operating step (not
shown).
In the case of direct application, the moving material web is
guided over the surface of the roll 1 and the liquid or pasty
medium is applied with the desired layer thickness directly
onto the moving material web.
The direction of movement of the material web or roll surface
is denoted in Figs. 1 and 2 with the reference sign 2.
The first exemplary embodiment of the application unit
according to the invention shown in two different conversion
variants in Figs. 1 and 2 has a basic structural group common
to both conversion variants which is described in more detail
in the following and the components of which are
substantially shown in shading in the Figures.
The basic structural group respectively comprises a support
beam 3 which supports the individual members of the
application unit and a distribution tube or pipe 4 through
which the liquid or pasty medium is supplied. The support
beam 3 has on its upper side an inclined rear wall 5
extending somewhat tangentially to the roller 1, the rear
217 1749
16
wall passing over in the region of its lower end into support
webs 6 for support journals 7. Supported on the support
journals 7 are front wall webs 8 secured on a front wall 9
which extends at a distance and parallel to the upper side of
the rear wall 5 of the support beam 3. The front wall 9 is
also called the outer wall and the rear wall 5 as well as the
wall areas adjoining this are also called the inner wall.
Between the front wall 9 and the rear wall 5, there is formed
a feed gap 10 which is connected with the interior of the
distribution tube 4 by means of a number of supply channels
11 which penetrate through the rear wall 5. Liquid or pasty
medium delivered through the distribution tube 4 can
therefore be supplied through the supply channels 11 into the
feed gap 10 as indicated with arrows.
The previously described structure of the basic structural
group is known in principle. However, the special feature
according to the invention consists in that the areas of the
front wall 9 and the rear wall 5 are designed for the
releasable attachment of attachable members selectively
either for the formation of an application means in the form
of an application chamber (compare Fig. 1) or for the
formation of an application means in the form of a free jet
nozzle (compare Fig. 2).
In contrast to the components of the basic structural group
characterized by shading, the attachable members for the
formation of the application chamber (Fig. 1) or the free jet
nozzle (Fig. 2) are merely illustrated by way of outlines for
better clarity. The securing members for the attachable
members can be designed in the most varied ways and are
therefore merely indicated by dot-dash lines in Figs. 1 and
2.
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As can be seen in Fig. 1, the attachable members for the
formation of the application chamber 12 comprise an
attachable doctor blade support 13 with a doctor blade member
14 in the form of a blade strip. The blade support 13 is
equipped in the present case with an adjusting means 15 which
acts on a blade base 16 by means of which the blade member 14
can be moved towards or away from the roll or the material
web for fine adjustment.
In the region of the front wall 9, the attachable members
also include an attachable ~mm;ng strip 17 which has an
overflow surface 18 that passes into an overflow surface 19
of the forward wall 9 and to which an excess collection and
discharging means 20 is connected.
The liquid or pasty medium supplied through the distribution
tube 4 therefore flows through the supply channels 11 into
the feed gap 10 and from there into the application chamber
12. The excess of liquid or pasty medium then flows out of
the stagnation chamber 12 via the ~mm;ng strip 17 and the
overflow surfaces 18 and 19 into the excess collecting and
discharging means 20 via which the excess liquid or pasty
medium is discharged for the purpose of processing.
As illustrated in Fig. 2, the releasable attachable members
for the formation of an application means in the form of a
free jet nozzle comprise an attachable nozzle strip Z1 which
is secured to the front wall 9 and has a concave guiding
surface 22 at its end facing the roll 1. The attachable
members additionally include a further nozzle strip 23 that
together with the nozzle strip 21 forms a dosing gap 24 which
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18
passes upstream into the feed gap 10 and through which the
liquid or pasty medium is discharged.
In the conversion variant of the application unit illustrated
in Fig. 2, the attachable nozzle strips 21 and 23 are shaped
in such a manner that the dosing gap 24 approximately forms a
right angle together with the feed gap 10. However, instead
of this preferred embodiment, the attachable members for the
free jet nozzle can also be designed in any other desirable
manner. Additionally, means can be provided by way of which
the nozzle strip 21 or the nozzle strip 23 can be adjusted
with respect to the opposite nozzle strip in order to alter
the dosing gap 24.
The application unit as a whole is additionally equipped with
a schematically illustrated advancing and tilting means.
The application unit can be moved approximately radially
towards or away from the roll 1 by means of the advancing
means. For this purpose, the arrangement as a whole is
secured to a pivot lever S which is hinged by means of its
right-hand end in the drawing to a fixed support L in such a
manner that it can be swung up and down about the rotational
axis D in the direction of the double arrow Z.
Further, the application unit can be swung about an axis
parallel to the roll axis by means of the tilting means and,
in this manner, the position of the application chamber 12 or
the free jet nozzle with reference to the material web or
roll surface can be adjusted. For this purpose, the entire
arrangement is pivotable on the pivot lever S about the
parallel axis lying in the center of the blade strip in the
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19
present exemplary embodiment, as indicated in the drawing
with the double arrow K.
As the application according to Fig. 2 with an application
means operating as a free jet nozzle has a greater "height"
than the application unit according to Fig. 1 operating with
an application chamber, the application unit must be moved
slightly away from the roll 1 by means of the advancing
means.
While the application unit in the first exemplary embodiment
illustrated in Figs. 1 and 2 is located approximately in the
"seven o'clock position" with reference to the roll 1,
Figs. 3 and 4 show a second exemplary embodiment in which the
application unit is arranged with reference to the roll 1
approximately in the "three o'clock position" of the roll.
This application unit also comprises a support beam 30 which
serves as a base for the individual members of the
application unit, and a distribution pipe 31 via which the
liquid or pasty medium is supplied.
The arrangement additionally has a front wall 32 and a rear
wall 33 between which a feed gap 34 lS formed. The feed gap
itself is connected with the distribution tube 31 by means of
supply channels 35. Liquid or pasty medium delivered through
the supply pipe 31 can therefore be fed via the supply
channels 35 into the feed gap 34, as indicated by arrows.
As in the first exemplary embodiment, the special feature in
the second exemplary embodiment also lies in that the basic
structural group is designed in the region of the front wall
32 and the rear wall 33 for the releasable attachment of
attachable members selectively either for the formation of an
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application means in the form of an application chamber
(compare Fig. 3) or for the formation of an application means
in the form of a free jet nozzle (compare Fig. 4).
As in the case of the first exemplary embodiment, the
components of the basic structural group of the application
unit are characterized in Figs. 3 and 4 by shading, while the
attachable members which form the application chamber
(Fig. 3) or the free jet nozzle (Fig. 4), respectively, are
merely illustrated in outline. Also in this exemplary
embodiment, the securing members for the attachable members
can be designed in the most varied ways. The securing
members are therefore only indicated in dot-dash lines in
Figs. 3 and 4.
As shown in Fig. 3, the attachable members for the formation
of the application chamber comprise an attachable blade
support 36 with a blade member 37 and an adjusting means 38.
Furthermore, in the area of the front wall 32, the attachable
members comprise an attachable damming strip 39 which has an
overflow surface 40 that opens into an overflow channel 41
with which an excess collecting and discharging means 42
conjoins. In order to ensure the flowing off of the excess
liquid or pasty medium over the discharge channel 41, a spray
means 43 is provided.
The releasable attachable members for the formation of an
application means in the form of a free jet nozzle in the
second exemplary embodiment illustrated in Fig. 4 include an
attachable nozzle strip 44, which is secured to the front
wall 32, and a nozzle strip 45, which is secured to the rear
wall 33. The securing means for the attachable nozzle strips
21747~9
21
44 and 45 are also merely shown with dot-dash lines in
Fig. 4.
The second exemplary embodiment illustrated in Figs. 3 and 4
naturally also has an advancing and tilting means, but this
is not shown for better clarity.
Further, in the second exemplary embodiment there are
members, also not illustrated, which are required for
operation but not necessary for understanding the invention.
In the two previously described exemplary embodiments
according to Figs. 1 and 2 and Figs. 3 and 4, respectively,
the attachable members for the selective formation of an
application chamber application means or a free jet nozzle
application means are designed in such a manner that, in both
conversion variants, the respective direction of rotation of
the associated roll 1 can be maintained.
However, the attachable members can be formed in such a
manner that in the case of conversion from one conversion
variant to the other, there is a reverse in the direction of
rotation of the associated roll 1, which acts as a counter-
roll in the case of direct application and as an application
roll in the case of indirect application. Such a design of
the attachable members which permits a reversal of the
rotational direction of the roll is realized in a third
exemplary embodiment explained in the following with
reference to Figs. 5 and 6.
In the third exemplary embodiment according to Figs. 5 and 6,
the corresponding components of the application unit are
denoted with the same reference signs as in the first
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22
exemplary embodiment according to Figs. 1 and 2. Therefore,
reference is also made to these explanations with regard to
the corresponding components.
In this third exemplary embodiment, a basic structural group
is again formed which is retained in both application unit
variants that in term are realized by means of releasably
mounted attachable members. This basic structural group
comprises a support beam 3, of which only a part is shown in
the Figures. The support beam 3 carries a distribution pipe
4 through which the liquid or pasty medium to be applied is
fed. Secured to the distribution pipe 4 is a rear or inner
wall 5 and joining with this are further rear or inner wall
sections 5A and 26. Additionally, the support beam 3 carries
a forward or outer wall 9 which forms a feed gap 10 together
with the rear or inner wall 5. The liquid or pasty medium
passes from the distribution pipe 4 via the supply channels
11 into the feed gap 10, from where the medium is fed to the
application means adjoining the basic structural group. An
excess collecting and discharging means 20 for the liquid or
pasty medium is mounted on the forward or outer wall 9.
In the variant according to Fig. 5, the previously described
basic structural group supports attachable members for the
formation of an application means in the form of an
application chamber 12. Blade support members 13, 13A and a
further member 25 are mounted on the area 5A of the rear wall
5. The blade support member 13A supports a blade member 14
in the form of a rolling blade. The blade support members
13, 13A together form a bent or angled blade support. The
attachable member 25 supports an adjusting means 15 known per
se by means of which the blade member 14 carried by the blade
support member 13A can be adjusted in the direction towards
2174719
23
the roll 1 or away from this. The adjusting means 15 is
indicated by an arrow.
An attachable member 17 in the form of a damming or
stagnation strip is mounted in the area of the front wall 9.
The ~mm;ng strip 17 borders the application chamber 12
together with the blade support member 13, 13A and the blade
member 14. On the outer side of the damming strip 17, there
is an overflow surface 18 over which the excess liquid or
pasty medium can flow from the application chamber into the
adjoining excess collecting and discharging means 20.
The roll 1 which acts as an application roll in the case of
indirect application and as a counter-roll in the case of
direct application rotates in the direction of the arrow 2 in
the variant with the application chamber shown in Fig. 5.
As illustrated in Fig. 6, in order to realize the free jet
nozzle application unit variant, instead of the attachable
members 13, 13A, 14, 17, 25, the attachable members 21 and 23
are mounted. The attachable member 21 in the form of a
nozzle strip is placed on the area 5A of the rear wall 5,
while the attachable member 23 in the form of a second nozzle
strip is placed on the area of the front wall 9. The two
nozzle strips 21 and 23 are shaped in such a manner that a
dosing gap 24 is formed between them and a free concave
deflecting surface 22 borders this along the nozzle strip 21.
The liquid or pasty medium to be applied leaves the
application means as a free jet and is guided at the
deflecting surface 22 in the appropriate direction of
application with respect to the surface of the roll 1.
_ 217~749
24
Also only indicated by means of an arrow is the adjusting
means 15 via which the nozzle strip 21 is movable towards or
away from the opposing nozzle strip 23 to adjust the dosing
gap 24.
The counter-roll or application roll 1 rotates in the
direction of the arrow 2 in the free jet nozzle application
unit variant according to Fig. 6. In order to realize the
reversal of the direction of rotation of the counter-roll or
application roll 1 after conversion from one application unit
variant to the other, the roll drive is provided with a
rotational direction alternator, which is not illustrated.
As a result of the appropriate design of the attachable
members and reversal of the direction of rotation of roll 1,
the operating means, i.e. especially the adjusting means 15,
remain on the same side of the coating machine. Therefore,
in both conversion variants, the operating personal together
with the associated operating and adjusting means remain on
the same operating side of the coating machine, which also
contributes to a quicker and less complicated conversion.
This third exemplary embodiment is also provided with an
advancing and tilting means although this is not shown for
reasons of better clarity. For the same reasons of better
clarity, further members required for operation but not
necessary for understanding the invention are not illustrated
in Figs. 5 and 6.
A fourth exemplary embodiment of the inventive application
unit is shown in Figs. 7 and 8. Corresponding components of
the application unit are denoted with the same reference
signs as in the first exemplary embodiment according to
~ 21747g9
Figs. 1 and 2. Therefore, reference is made to the
explanations regarding the first exemplary embodiment in
respect of the components 3, 4, 5, 6, 7, 8, 9, 10 and 11.
Reference is also made in respect of the advancing and
tilting means D, K, L, S and Z to the explanations of the
first exemplary embodiment.
In both conversion variants according to Figs. 7 and 8, a
common attachable member 21A is retained which is mounted to
an area 5A of the rear or inner wall 5. In the variant of
the free jet nozzle application unit as shown in Fig. 7, this
common attachable member 21A serves as a nozzle strip and,
together with a second nozzle strip 23 mounted in the area of
the forward or outer wall 9, forms a dosing gap 24 acting as
a free jet nozzle. The attachable member 21A is shaped in
such a manner that it has a free concave deflecting surface
22 which adjoins the dosing gap 24 and guides the free jet of
the liquid or pasty medium in the desired direction with
respect to the surface of the roll 1.
The members 25A, 26A and 27A form an adjusting means for the
dosing gap 24. By means of adjusting screws 26 distributed
across the machine width and supported on the strip 25A,
which itself is securely fastened to the base of the common
attachable member 21A, the top area of the nozzle strip 21A
can be moved closer to or away from the nozzle strip 23. For
this purpose, the nozzle strip 21A has a thinner area in the
middle thereof which permits a certain elastic deformation of
the top of the strip. The top area of the nozzle strip 21A is
also capable of being deformed with respect to the cover 27A,
which is connected securely to the strip 25A by means of the
securing means indicated only schematically in Fig. 7.
~_ 21717~9
26
Naturally, a different adjusting means can be used to that
described by way of example here.
The counter-roll or application roll 1 moves in the direction
of arrow 2. Arranged downstream of the free jet nozzle
application unit in the direction of rotation of the roll is
a fine dosing device F which finely doses the applied coating
of liquid or pasty medium by means of a fine dosing blade.
Fig. 8 shows the application chamber conversion variant of
the fourth exemplary embodiment in which the basic structural
group as well as the common attachable member 2lA have been
retained as in the case of the free jet nozzle application
unit variant according to Fig. 7. The strip 25A and the
screws 26A are also retained, but the adjusting screws 26A do
not have any function in the application chamber conversion
variant. Instead of the cover member 27A, an attachable
member in the form of a ~l~mming strip 17 is placed on the
common attachable member 21A and the strip 25A and securely
fastened to these by means of (only schematically shown)
fastening means. The tl~mm;ng strip 17 is provided on its
outer surface with an overflow surface 18 to which an access
collecting and discharging means 20 is connected.
Blade supporting me-mbers 13 and 13A as well as a blade 14
held in the blade supporting member 13A are attached in the
area of the forward or outer wall 9. The blade supporting
members 13, 13A, the blade 14 and the damming strip 17 border
an application chamber 12. Together with the blade supporting
member 13, the attachable member 21A, which formed a part of
the dosing gap 24 in the free jet nozzle variant according to
Fig. 7, now extends the feed gap 10 to the application
chamber 12. Also in this exemplary embodiment, there is a
~_ 21747~9
known adjusting means 15 in order to move the blade 14
towards or away from the roll 1. In this fourth exemplary
embodiment, the rotational direction (see arrow 2) of the
roll 1 is maintained in both conversion variants.
The previously described fourth exemplary embodiment enables
a quicker and more simple conversion from one variant to the
other because the attachable member 21A can be retained in
both variants and therefore can be associated with the basic
structural group. Consequently, upon conversion from the one
variant to the other, fewer attachable parts need to be
changed.
In the fifth exemplary embodiment of the inventive
application unit which is illustrated in Fig. 9, a basic
structure is provided which is made up of a basic structural
group and an application means in the form of a free jet
nozzle arrangement located thereon.
The basic structural group comprises a support beam 3 which
carries the individual members of the application unit, and a
distribution pipe 4 through which the liquid or pasty medium
is supplied. The support beam 3 has a rear or inner wall 5
which extends approximately radially to the roll 1 and passes
over into the wall of the distribution pipe 4 in the present
exemplary embodiment. In the area of the lower end of the
wall 5, there are support webs 6 arranged beneath the
distribution pipe 4 which carry support journals 7. Front
wall webs 8 supported on the support journals 7 are secured
to a forward or outer wall 9 that in turn extends at a
distance and approximately parallel to the outer surface of
the rear wall and the adjoining wall of the distribution
2174749
28
pipe 4 and, in this manner, forms a feed gap 10 which is also
aligned approximately radially to the roll 1.
The feed gap 10 itself is connected with the interior of the
distribution pipe 4 by means of a number of supply channels
11 which penetrate the wall of the distribution pipe 4.
Liquid or pasty medium delivered through the distribution
pipe 4 therefore can be supplied via the supply channels 11
into the supply gap 10, as indicated by arrows.
The front wall 9 is provided in the area of its end distal
from its support journals 7 with a lip 12B which borders a
dosing gap 13B of the free jet nozzle.
On the upper side of the support beam 3 facing the roll 1,
there is a lip member 14B with a concave deflection surface
15B which forms the dosing gap 13B of the free jet nozzle
together with the lip 12B.
The basic structure described above forms a free jet nozzle
application unit known in principle. The liquid or pasty
medium supplied via a distribution pipe 4 flows in this free
jet nozzle arrangement via the supply channels 11 into the
feed gap 10 and the dosing gap 13B and then exits between the
lips 12B and 14B, deflected by means of the deflection
surface 15B, as a free jet, which then impinges in the case
of direct application onto the material web supported by the
counter-roll 1 or, in the case of indirect application, on
the roll 1 which then acts as the application roll. Thus,
with the previously described basic structure, there is a
functioning free jet nozzle application unit in which the
further structural members shown in Fig. 9 mounted on the lip
members 12B and 14B are naturally omitted.
? ~ . J
-- 2i74749
29
The entire application unit is equipped with a schematically
illustrated advancing and tilting means. The application
unit can be moved approximately radially towards and away
from the roll 1 by means of the advancing means. For this
purpose, the entire arrangement is secured to a pivot lever S
which is hinged with its right-hand end in the drawing to a
fixed support L in such a manner that it can be pivoted up
and down about the rotational axis D in the direction of the
twin arrow Z. Further, the application unit can be swung
about an axis parallel to the roll axis by means of the
tilting means and, in this manner, the angle of the
application unit with respect to the material web or roll
surface can be adjusted. For this purpose, the entire
arrangement is pivotable on the pivot lever S about the axis
lying parallel to the roll axis and, in the present exemplary
embodiment, in the center of the member 20B, as indicated by
a double arrow K in the drawing. The member 20B is described
in more detail later.
For the previously described conversion variant with a free
jet nozzle arrangement in the form of the two lip members 12B
and 14B, the associated roll position is indicated by a dot-
dash line. The corresponding adjustment of the application
unit with respect to the roll 1 takes place by means of the
previously described advancing and tilting means. In the
mode of operation as a free jet nozzle application unit,
there is a fine dosing means F downstream of the application
unit as seen in the direction of movement of the roll, which
is denoted by the arrow 2. If necessary, this can also be
present in the mode of operation with the application
chamber.
2174749
As already explained, in the case of conversion of the above-
described arrangement to an application means operating with
an application chamber, the above-described application unit
previously had to be completely removed, i.e. together with
the basic structural group, and replaced by a new application
unit operating with an application chamber. This work-
intensive removal and remounting is no longer necessary in
accordance with the invention. Rather, according to the
invention, only the areas which carry out the actual
application of the liquid or pasty medium have to be
converted, as described in the following and illustrated in
Fig. 9.
As can be recognized in Fig. 9, in accordance with the
invention, the lips 12B and 14B are formed for releasable
attachment of members to form an application chamber for the
liquid or pasty medium. For conversion of the free jet
nozzle application unit to an application unit operating with
an application chamber, it is therefore merely necessary to
place blade support members 18B and l9B comprising a blade
member 20B on the lip 12B and to place a ~mmlng strip 16B on
the lip 14B.
In this case, the releasably attached damming strip 16B is
provided with an overflow surface 17B which leads to an
excess collecting and discharging means 23B. After mounting
of these attachable members, there is the application chamber
application unit as shown in Fig. 9.
The blade support members 18B and l9B are subdivided into a
blade holder 18B and a blade base l9B in which the blade
member 20B in the form of a blade bar is held. The blade l9B
can be adjusted with respect to the blade holder 18B by means
2174749
of an adjusting means 21B in accordance with the respective
requirements. As already described, the entire arrangement
can also be swung by the tilting means about the axis of the
blade bar (or, when using a doctor blade mem~ber in the form
of a knife, about its effective edge), as indicated by the
twin arrow K. The blade base 1 9B and parts of the blade
holder 18B together with the ~Amm;ng strip 16B form an
application chamber 22B out of which the liquid or pasty
medium is then applied via the blade member 20B onto the
surface of the roll 1 or the surface of the material web.
The excess liquid or pasty medium flows out of the
application cha-mber 22B over the da-m-ming strip 1 6B and
arrives via the overflow surface 17B into the excess
collecting and discharging means 23B for the purpose of
further processing.
The attachable members in the form of the blade support 18B,
l9B and the ~Amm;ng strip 16B are easy and quick to handle
and can be attached and dismounted in a simple manner in
order to convert the free jet nozzle application unit to the
application chamber application unit illustrated in Fig. 9,
and vice versa.
As the application unit operating in terms of its basic
structure with a free jet nozzle has a smaller "height" than
the conversion variant with the application chamber 22B, the
application unit must be advanced by means of the advancing
means for operation with the free jet nozzle and withdrawn
for operation with the application chamber. Further, the
optimal angular position of the free jet nozzle or of the
application unit with respect to the roll 1 can then be
adjusted if necessary by means of the tilting means.
21747~9
32
In the sixth exemplary embodiment of the inventive
application unit, a basic structure is formed as illustrated
in Fig. 10. The basic structure consists of a basic
structural group and an application means in the form of an
application chamber located thereon.
Regarding the basic structural group 3, 4, 5, 6, 7, 8, 9, 10
and 11, reference is made to the previous explanations in
respect of the fifth exemplary embodiment according to
Fig. 9. Reference is also made to these explanations in
respect of the adjusting and tilting means D, K, L, S and Z.
The corresponding components are denoted with the same
reference signs in the fifth and sixth embodiments.
The forward or outer wall 9 is formed in the region of its
end distal from the support shaft 7 as a damming strip 12C
and forms an overflow surface 13C on its outer surface. The
overflow surface 13C passes in the region of the front wall
web 8 into an excess collecting and discharging means 14C.
Connected to the area 5C of the rear or inner wall 5 is a
blade support 18C which carries a blade member 17C in the
form of a knife. The blade member 17C is held in the blade
support 18C by means of a clamping means 18C and can be moved
towards and away from the material web surface or the roll
surface by means of an adjusting means l9C which is arranged
along the strip 16C.
An application chamber 20C is bordered by the blade support
member 18C including the blade knife 17C, and the damming
strip 12C. Such an application chamber application unit as
previously described is known in principle. The liquid or
pasty medium fed via the distribution pipe 4 flows through
~ 2174749
the supply channels 11 into the feed gap 10 and from there
into the application chamber 20C formed between the ~mm; ng
strip 12C and the blade member 17C. The excess liquid or
pasty medium flows away over the damming strip 12C and passes
over the overflow surface 13C into the excess collecting and
discharging means 14C for the purpose of processing.
The application unit can be swung about an axis parallel to
the roll axis by means of a tilting means and, in this
manner, the angle of the blade member 17C with respect to the
material web or roll surface can be adjusted. For this
purpose, the entire arrangement is capable of being swung on
the pivot lever S about the parallel axis lying approximately
along the effective edge of the blade member 17, as indicated
by a double arrow K in the drawing.
As already explained, in the conversion to an application
means operating with a free jet nozzle, the application
chamber application unit illustrated in Fig. 10 previously
had to be removed completely, i.e. together with the basic
structural group consisting of the support beam, the
distribution pipe, the connectors and other means, and
replaced by a new application unit equipped with a free jet
nozzle. In accordance with the invention, this work-
intensive removal and conversion is no longer necessary.
Rather, only those areas which effect the immediate
application of the liquid or pasty medium are converted, as
schematically illustrated in Fig. 11. The basic structural
group, i.e. the support beam, the distribution pipe and the
means required for connection can therefore remain and, in
accordance with the invention, both an arrangement operating
with a free jet nozzle as well as an arrangement operating
with an application chamber can be used. Only specific
-
2174799
34
attachable members which can be handled more easily and
quickly need to be mounted or removed for the conversion.
As can be recognized in Fig. 11, the damming strip 12C of the
front wall 9 and the blade support 18C are formed for the
releasable attachment of members to form an application means
operating as a free jet nozzle. For the purpose of conversion
of the application chamber application unit according to
Fig. 10 to an application means operating as a free jet
nozzle, it is only necessary to place an attachable member in
the form of a nozzle strip 21C onto the ~mml ng strip 12C and
to mount a second nozzle strip 24C on the blade support 18C
instead of a blade member 17C, the second nozzle strip
together with the nozzle strip 21C then forming a dosing gap
25C which acts as a free jet nozzle. In the exemplary
embodiment, the dosing gap 25C together with the feed gap 10
approximately form a right angle. On the nozzle strip 21C,
there is a free concave deflection surface 22C which adjoins
the dosing gap 24C and deflects the free jet of the liquid or
pasty medium in the desired direction with respect to the
roll or material web surface. The counter-roll or
application roll 1 turns in the same rotational direction in
both conversion variants according to Figs. 10 and 11, as
indicated by an arrow 2.
In the example, the securing of the nozzle strip 21C is
effected by means of securing screws 23C, but the mounting of
the attachable members to form the free jet nozzle dosing gap
can take place in the most varied ways.
The nozzle strip 24C is held in the clamping means of the
blade support 18C and can be adjusted with respect to the
opposite nozzle strip 21C by means of the adjusting means
21754749
l9C, which extends along the strip 16C, in order to adjust
the dosing gap 25c.
The attachable members in the form of the nozzle strips 21C
and 24C can be handled easily and quickly and be mounted and
removed in a simple manner in order to convert the basic
structural unit with an application chamber, as illustrated
in Fig. 10, to a free jet nozzle application unit according
to Fig. 11, and vice versa.
Since the application unit according to Fig. 11 comprising an
application means operating as a free jet nozzle has a
greater "height" than the application unit according to
Fig. 10 operating with the application chamber, the
application unit must be withdrawn somewhat from the roll 1
by means of the advancing means.
