U.S. patent application number 16/608897 was filed with the patent office on 2020-03-19 for infrared radiator.
The applicant listed for this patent is VOITH PATENT GMBH. Invention is credited to DIRK HOECKELMANN, JUAN PANIAGUA.
Application Number | 20200088403 16/608897 |
Document ID | / |
Family ID | 61691431 |
Filed Date | 2020-03-19 |
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United States Patent
Application |
20200088403 |
Kind Code |
A1 |
PANIAGUA; JUAN ; et
al. |
March 19, 2020 |
INFRARED RADIATOR
Abstract
An infrared radiator for the heat treatment of a material web
includes an incandescent body with a flow-receiving surface to be
impinged by a gas-air mixture that is supplied to the infrared
radiator and to be heated by combustion of the gas-air mixture. The
incandescent body is manufactured as a sheet material that is
formed of a multiplicity of threads. The sheet material is
manufactured by primary forming.
Inventors: |
PANIAGUA; JUAN;
(MOENCHENGLADBACH, DE) ; HOECKELMANN; DIRK;
(MOENCHENGLADBACH, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
VOITH PATENT GMBH |
HEIDENHEIM |
|
DE |
|
|
Family ID: |
61691431 |
Appl. No.: |
16/608897 |
Filed: |
February 19, 2018 |
PCT Filed: |
February 19, 2018 |
PCT NO: |
PCT/EP2018/053996 |
371 Date: |
October 28, 2019 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F23D 2900/14125
20130101; F23D 2203/103 20130101; F23D 14/145 20130101 |
International
Class: |
F23D 14/14 20060101
F23D014/14 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 28, 2017 |
DE |
10 2017 109 154.8 |
Claims
1-11. (canceled)
12. An infrared radiator for the heat treatment of a material web,
the infrared radiator comprising: an incandescent body having a
flow-receiving surface to be impinged by a gas-air mixture supplied
to the infrared radiator and to be heated by a combustion of the
gas-air mixture; said incandescent body being manufactured as a
sheet material formed of a multiplicity of threads and said sheet
material being manufactured by primary forming.
13. The infrared radiator according to claim 12, wherein said sheet
material is a self-supporting sheet material.
14. The infrared radiator according to claim 12, wherein said
threads of said sheet material are interconnected in an articulated
manner at respective intersection points.
15. The infrared radiator according to claim 12, wherein said
threads are formed spirally and said sheet material is a spiral
braid with two directly adjacent threads respectively connected to
one another in each case by meshing at intersection points.
16. The infrared radiator according to claim 12, wherein said sheet
material is a woven fabric, comprising threads that serve as warp
threads and that are interwoven at intersection points with threads
that serve as weft threads, and wherein said threads have a
wave-shaped outer contour.
17. The infrared radiator according to claim 16, wherein said woven
fabric is a plain weave, with directly adjacent threads that serve
as weft threads weaving alternately through threads that serve as
warp threads, along different weaving paths.
18. The infrared radiator according to claim 12, wherein said
threads are made of a comparatively flexurally rigid material.
19. The infrared radiator according to claim 18, wherein said
threads are made of a ceramic.
20. The infrared radiator according to claim 12, wherein said
flow-receiving surface is at least one delimiting side of said
incandescent body.
21. The infrared radiator according to claim 12, further comprising
a burner plate, and wherein said incandescent body is arranged
behind said burner plate in a flow direction of the gas-air
mixture.
22. The infrared radiator according to claim 21, wherein said
incandescent body directly adjoins said burner plate viewed in the
flow direction of the gas-air mixture.
23. The infrared radiator according to claim 12, wherein said
incandescent body is manufactured from a plurality of layers of
said sheet material arranged on top of one another.
Description
[0001] The invention relates to an infrared radiator, specifically
according to the independent claim.
[0002] Generic infrared radiators are used in drying arrangements
for heat treatment, such as drying a material web, for example a
paper, tissue or cardboard web. These drying arrangements are part
of machines for manufacturing and/or treating such material webs.
Nonwoven glass fabrics would also be possible. A preferred area of
application is the drying of moving paper, tissue or cardboard webs
in paper mills, for example behind coating devices, viewed along
the running direction of the material web.
[0003] Infrared radiators that are known in the art have for
example a plurality of rods that are preferably arranged in one
plane, i.e. that are coplanar. However, arranging the rods in a
plurality of parallel planes spaced from a burner plate is also
known. The rods of generic infrared radiators are made of ceramic.
Infrared radiators of this kind may be gas-powered. In that case, a
burner is associated with them. This burner is operated with a
gas-air mixture. The burner has a burner plate that is charged with
the gas-air mixture. The gas-air mixture is ignited for example
using an electrode. The resulting flame heats the rods. The rods
serve as incandescent bodies. They transfer the heat to the
material web in the form of infrared radiation. In place of rods,
highly heat-resistant metals, for example in the form of grids or
porous ceramics, are also known as incandescent bodies.
[0004] Infrared radiators of this kind are used as surface
radiators in the heat treatment of material webs. For this purpose,
a multiplicity of such infrared radiators are arranged next to each
other along the width and/or length of the material web to be
treated. The required number of radiators is selected based on the
width of the material web to be dried and the desired heating
power. Using such infrared radiators, surface temperatures of
1100.degree. C. and above may be achieved on the incandescent
body.
[0005] A drawback of infrared radiators known from the prior art is
that their radiation efficiency is not optimal for every
application. It has also been shown that the gas-powered infrared
radiators that are known in the art produce a very high proportion
of nitrogen oxides (NOx) and carbon monoxides (CO) from the
combustion of the gas-air mixture.
[0006] Further, previous incandescent bodies made from ceramic
components such as rods may cause the entire rod to fall onto the
material web in the event of a break, which may damage the
machine.
[0007] The present invention relates to the above-discussed subject
matter.
[0008] The object of the invention is to create an infrared
radiator that is improved over the prior art. In particular, the
radiation efficiency and the exhaust gas behavior of the infrared
radiator with regard to nitrogen oxides and carbon monoxide should
be improved. Also, in the event of a possible break of the
incandescent body, parts of the incandescent body should not fall
onto the material web and the associated machine damage and
downtime should be prevented.
[0009] This object is accomplished by an infrared radiator
according to the features of the independent claim.
[0010] The term "radiation efficiency" refers to the ratio of the
power the infrared radiator supplies to the power it
radiates--here, in the form of infrared radiation.
[0011] An infrared radiator according to the present invention
dries a material web, for example in the intended operation
(operating state) of the drying arrangement or the machine. This is
the state in which the gas-air mixture within the infrared radiator
burns and simultaneously heats the (at least one) incandescent
body. Combustion may take place in the space bounded by the burner
plate and at least one incandescent body--in this case referred to
as the combustion chamber.
[0012] An incandescent body, in the sense of the present invention,
is thus the object through which the gas-air mixture or its
combustion products flow, and which is heated as a result of the
combustion of the gas-air mixture. It is the part of the infrared
radiator that glows due to being heated. Incandescence refers to
the emission of radiation that is visible to the human eye. The
incandescent body may be that part of the infrared radiator
arranged behind the burner plate in the flow direction of the
gas-air mixture. It may be at a distance from or in contact with
the burner plate. The incandescent body is thus heated by the
flames that are generated as a result of the combustion process,
for example, on the side of the burner plate facing the
incandescent body. The incandescent body could also be said to
comprise all those elements that, together with the burner plate,
delimit the combustion chamber of the infrared radiator. The at
least one incandescent body may represent the outermost surface of
the infrared radiator, which is directly opposite the material web
to be treated. In such a case, the incandescent body is then
arranged between the burner plate and the material web.
[0013] As used in the present invention, a "sheet material" is a
planar structure such as woven fabric, knitted fabric, crocheted
fabric, braided fabric or lace structures. Sheet materials are
basically made up of a multiplicity of linear structures such as
threads. In such sheet materials, the linear structures form or
delimit openings of the sheet material. The sheet material could
also be said to be designed in the manner of a net or grid, with
the openings representing the interstices of the net or grid. These
openings--in a top view of such a sheet material--may take on
different geometric shapes, such as polygons, for example
rhombuses, rectangles or hexagons. The planar extension of such
openings is measured in length and width in the aforementioned top
view. Taken together, the openings represent the cavity of the
incandescent body and are flowed to or through by the gas-air
mixture or the combustion products thereof during operation of the
infrared radiator.
[0014] "Woven fabric" refers to a sheet material woven from warp
and weft threads. These warp and weft threads cross each other. The
woven fabric may comprise one or a plurality of different thread
systems, preferably a plurality having different mechanical
properties. But it is also possible that such woven fabrics may be
used in which the warp and weft threads are made of the same
material. Threads that serve as warp and weft threads touch each
other at the intersections.
[0015] A knitted or crocheted fabric may be a mesh. The term mesh
is understood to mean such sheet materials in which a loop formed
by a thread is interlaced with another loop. Knitted fabrics may be
obtained, for example, by knitting or crocheting, with each mesh
row being made up of a single thread. Knitted fabrics consist of
one or more thread systems. A loop then engages in the loop of the
preceding mesh row. In crocheted fabrics, on the other hand, at
least two thread systems are used and the meshes of one mesh row
are formed simultaneously. The loops define the intersection points
at which the threads touch each other.
[0016] The term braid refers to an entanglement or interlacing
between directly adjacent threads. The threads may be
spiral-shaped. The self-supporting sheet material appears as if the
individual threads were generated by interlacing the spirals. In
other words, it appears as if a thread had been twisted lengthwise
into an adjacent thread, so that both spirals interlace with each
other and touch at the intersection points. The longitudinal
central axes of the spirals then lie parallel to each other in this
sheet material. This is referred to as a spiral braid.
[0017] In principle, a distinction is made as to whether the sheet
materials are capable of supporting themselves after they are
produced. This applies to the structures mentioned above, with the
exception of scrims. Scrims are also sheet materials that consist
of one or more layers of parallel threads. However, these threads
are not fixed to each other at their intersection points in a
material-fit, force-fit or positive-fit manner. Such a scrim is
therefore not self-supporting, i.e. when moved, it loses the shape
it has been given. In order for the scrim to retain its shape, the
threads laid on top of each other must be held by force.
Accordingly, when the infrared radiator according to the invention
is ready for operation, the incandescent body is not designed as a
scrim. Therefore for the purposes of the invention, scrims should
not fall under the concept of a sheet material, i.e. should be free
of such a structure. Scrims as intermediate products could be
protected by the invention as long as they are subsequently
processed in such a way that they are fixed to each other, for
example, at their intersection points.
[0018] In other words, for the purpose of the present invention,
sheet materials exhibit repetitive, preferably regular patterns
formed by the threads. In contrast, nonwovens are a random
arrangement of fibers that are interlaced with each other or held
together by a binder. Therefore, nonwovens do not fall under the
term "sheet material" according to the present invention, and thus
a nonwoven expressly does not constitute a sheet material. The
advantage of using regular pattern-forming sheet materials is that
over the entire extension of the sheet material a uniform
combustion and thus a uniform exhaust gas behavior takes place when
the sheet material is used as an incandescent body.
[0019] For purposes of the invention, the term "thread" refers to a
linear, long, thin structure. Such a thread is much longer than it
is wide, i.e. the diameter of the thread may be between 1 and 10 mm
and the thread may have a length of up to 300 mm. The thread may be
made of a flexurally rigid material, i.e. a material with
comparatively high flexural rigidity such as a ceramic. The term
flexural rigidity refers to the product of the elastic modulus with
the corresponding geometric moment of inertia. For example, a
material having a comparatively higher elastic modulus, or a thread
made therefrom, is more flexurally rigid than another thread with
the same geometric moment of inertia. The term elastic modulus
refers to a material characteristic used in materials engineering
that describes the relationship between stress and elongation
during the deformation of a solid body with linear-elastic
behavior. For purposes of the invention, a long and thin thread as
described above is flexurally rigid if it does not change its
embossed outer contour as soon as it is removed from the sheet
material with at least partial dissolution of the sheet material.
Flexurally nonrigid threads may be manufactured by the methods
mentioned above, such as weaving or knitting, because the thread is
flexible and its outer contour may be freely shaped during the
process. On the other hand, flexurally rigid threads cannot be
manufactured by such methods without changing or destroying their
outer contour. Therefore, according to the invention, such sheet
materials are manufactured by means of primary forming. Thus, the
entire sheet material--and not just the individual threads--is
produced by primary forming. It is therefore preferable that it be
monolithic and thus form a single unit.
[0020] An articulated connection according to the invention enables
the individual threads of the self-supporting sheet material to
move relative to each other at the intersection points. The joints
are therefore formed by the threads themselves at the intersection
points of the threads. The joints are preferably swivel joints.
[0021] For the purpose of the invention, a "material web" is a
fibrous web, i.e. a scrim or tangle of fibers such as cellulose
fibers, plastic fibers, glass fibers, carbon fibers, additives,
admixtures or the like. For example, the material web may be a
paper web, cardboard web or tissue web. The web may substantially
comprise cellulose fibers, with small quantities of other fibers or
additives and admixtures being present. This adaptation to a
particular application is left to the skilled person.
[0022] References to the flow direction of the gas-air mixture in
the invention refer to the main flow direction of the particles of
the gas-air mixture. This direction corresponds, for example, to a
perpendicular to the largest surface of the burner plate of the
infrared radiator through which the gas-air mixture flows (the
flow-receiving surface of the burner plate). The flow-receiving
surface may therefore be at least one delimiting side, i.e. the
surface spanned by the spatial length and width of the burner
plate. The delimiting side may be spanned by the long and wide
edges (of the flow-receiving surface) of the burner plate. Thus,
the gas-air mixture may flow through the burner plate at its
largest delimiting surface that faces the gas supply or the
premixing chamber. If the burner plate is designed as a cuboid, the
flow-receiving surface is at least one side face of the cuboid.
Because the incandescent body or its envelope may also be designed
as a cuboid, the flow-receiving surface of the incandescent body is
also a side face (delimiting surface) of the cuboid, which
represents a flat surface. Therefore, the above definition also
applies analogously to the incandescent body and its flow-receiving
surface. Thus the incandescent body is also flowed along this
flow-receiving surface together with the gas-air mixture or the
combustion products thereof. The flow direction of the gas-air
mixture may also be perpendicular to the largest delimiting surface
or flow-receiving surface. The flow direction of the gas-air
mixture through the incandescent body may be the same as the flow
direction through the burner plate. The flow-receiving surface of
the incandescent body may be identical to the flow-receiving
surface of the burner plate, so that both have the same area. It
may be the surface that the incandescent body and the burner plate
share when they abut one another directly.
[0023] When reference is made in the present invention to one
element directly abutting another element, this means that the two
elements are in direct contact with each other without anything
else--and, preferably, without any distance--between them.
[0024] If the invention refers to ceramic, this is understood as a
technical ceramic. Examples of this include, for example, silicon
carbide and molybdenum silicide. High-temperature-resistant metals
such as FeCrAl compounds or heat conductor alloys would also be
suitable, in principle, as materials for incandescent bodies.
[0025] If reference is made to the incandescent body being made of
a plurality of layers arranged one above the other, this means that
a plurality of layers of sheet materials may also be provided that
are arranged one behind the other in the flow direction of the
gas-air mixture. This means that the layers are stacked one above
the other, when viewed in the flow direction of the gas-air
mixture. This affords, according to the invention, the advantage
that the exhaust gas values may be further improved.
[0026] The term "at least partially" refers to at least a part of
the incandescent body.
[0027] If reference is made to one element surrounding another at
least partially, this means that it either partially or completely
surrounds or envelops the corresponding element.
[0028] The term "primary forming" means that the relevant element
has been manufactured by a manufacturing process in which a solid
body is generated from a formless substance. Examples of this are
casting, sintering, 3D printing.
[0029] Furthermore, the invention relates to a drying arrangement
for heat treatment of a material web, comprising an infrared dryer
that has a plurality of infrared radiators according to the
invention, preferably arranged in the width and/or length direction
of the material web to be treated. Such a drying arrangement may
have at least one air dryer for directing hot air and/or a
combustion product of the gas-air mixture from the plurality of
infrared radiators onto the material web to be treated. In
addition, the at least one air dryer and the at least one infrared
dryer may be arranged one behind the other as seen in the running
direction of the material web to be treated, and the at least one
infrared dryer may preferably be connected upstream of the at least
one air dryer as viewed in the running direction of the material
web to be treated.
[0030] The invention also relates to the incandescent body of claim
1 per se, as well as such a body having the features of the
dependent claims.
[0031] Finally, the invention relates to a machine for
manufacturing and/or treating a material web, preferably a paper
machine, comprising at least one infrared radiator according to the
invention, or such a drying arrangement.
[0032] The invention is described in greater detail below with
reference to the drawings, without restricting the invention's
generality. The drawings show the following:
[0033] FIG. 1 a schematic, partially cut-away and not-to-scale
representation of one embodiment of an infrared radiator;
[0034] FIG. 2 spatial representation of a possible embodiment of an
incandescent body according to the invention;
[0035] FIG. 3 a highly schematized representation of a drying
arrangement in a three-dimensional view according to one
embodiment.
[0036] FIG. 1 shows an exemplary embodiment of the invention in a
schematic, partially cut-away view through a plane that is
perpendicular to the material web and parallel to the running
direction (indicated by the arrow). The drawing shows an infrared
radiator 1, which may be part of a drying arrangement 9. During
normal operation, the infrared radiator 1 is arranged at a distance
from the material web 8, for example above it. The radiator forms a
burner that is arranged in a housing 11.1. This housing has, for
example, a rear wall and a plurality of side walls. The rear wall
is located on the side (rear side) of the infrared radiator 1
facing away from the material web 8. An opening 2 is provided in
this wall, through which a fuel, for example gas and air (an
ignitable, combustible gas-air mixture) may enter a mixing chamber
3. The corresponding supply lines outside the infrared radiator 1
are not shown in detail. The mixing chamber 3 is delimited on one
side by a gas-permeable burner plate 4 and on the other side by the
housing 11.1, here the rear wall thereof. The gas-air mixture flows
into the burner plate 4 at a flow-receiving surface corresponding
to the rear side of the infrared radiator 1 and passes through the
gas-permeable burner plate 4, to be combusted. From there the
mixture flows into a combustion chamber 5. This chamber is
delimited or formed jointly by the burner plate 4 and an
incandescent body 6. The gas-permeable burner plate 4 may be said
to separate the mixing chamber 3 from the combustion chamber 5. In
the latter chamber, the gas-air mixture ignites. The heat released
heats the incandescent body 6 until this body begins to glow. As a
result, the body emits infrared rays toward the material web 8 to
be dried. Both the burner plate 4 and the incandescent body 6 have
a slab-shaped or cuboidal outer contour. In principle, a different
outer contour would be possible. In this case, the flow-receiving
surface of the incandescent body 6 corresponds to the
flow-receiving surface of the burner plate 4. In other words, the
two flow-receiving surfaces are the same. They correspond in this
case to the clear width of the housing 11.1 that accommodates both
the burner plate 4 and the incandescent body 6.
[0037] Irrespective of the embodiment shown, the infrared radiator
1 with its incandescent body 6 faces the material web 8; in the
case shown, it does so in such a way that the incandescent body 6
runs parallel thereto. However, this need not necessarily be the
case. The infrared radiator 1 may also run at an angle thereto. As
shown in FIG. 1, the burner plate 4 and the incandescent body 6 are
connected in series, viewed in the flow direction of the gas-air
mixture. The incandescent body 6 is arranged downstream of the
burner plate 4.
[0038] According to the embodiment of FIG. 1, the incandescent body
6 is designed as a gas-permeable regular grid. This grid may be
formed by at least one sheet material. This structure is made up of
a multiplicity of threads that delimit the openings of the grid.
Consequently, the gas-air mixture passing through the burner plate
4 may also flow through all openings of the incandescent body 6
(simultaneously).
[0039] The incandescent body 6 is arranged at a distance from the
burner plate 4, viewed in the flow direction of the gas-air mixture
or the combustion products thereof. In other words, the combustion
chamber 5 is formed by the space jointly delimited by the burner
plate 4 and the incandescent body 6. The burner plate 4 and
incandescent body 6 are arranged parallel to each other with regard
to their flow-receiving surfaces or delimiting sides.
[0040] Although this is not shown in the drawings, it would be
possible for the incandescent body 6 to directly abut the burner
plate 4. This means that both are arranged without distance from
each other and preferably parallel to each other.
[0041] Irrespective of the embodiment shown, it would be
conceivable in principle, for example to provide a plurality of
layers of an incandescent body 6, or more precisely several layers
of sheet materials, which could be arranged at a distance from the
burner plate 4 in the flow direction of the gas-air mixture or the
resulting combustion products.
[0042] FIG. 2 shows a spatial representation of a possible
embodiment of the incandescent body 6 according to the invention as
a sheet material. The incandescent body is made from a multiplicity
of threads 15. The sheet material is designed, by way of example,
as a spiral braid. For this purpose, the threads 15 are interlaced
in the manner of spirals. The longitudinal central axes of the
threads 15 run parallel to each other over the entire spatial
extent of the resulting sheet material. Threads 15 that are
directly adjacent to each other are connected to each other in such
a way that the spirals thereof are screwed into one another. As a
result, the threads 15 are respectively mounted to each other in an
articulated manner at the shared intersection points. This
interlocking of the threads 15 results in a loss-proof structure.
In other words, if a part of a thread 15 breaks, it is held by the
adjacent threads 15 at the intersection points. As a result, the
probability that parts of the broken thread will fall onto the
material web 8 is significantly minimized. Breakage may occur if
the thread 15 is made of a ceramic.
[0043] Although not shown, the incandescent body 16 could also be
manufactured in the manner of a woven fabric. In that case, two
directly-adjacent threads that are designed as weft threads weave
the same weaving path through the warp threads, perpendicular to
the threads that act as warp threads.
[0044] For the production of such sheet materials, primary forming
methods such as 3D printing may be used.
[0045] Irrespective of the embodiments shown, the increased surface
area of the incandescent body 6 may considerably increase the
radiation efficiency due to the wavy or spiral outer contour of the
threads 15. This is achieved by increasing the surface area for the
combustion of the gas-air mixture due to the selected outer
contour, which results in a higher energy absorption from the
combustion products of the gas-air mixture. This may also reduce
the proportion of nitrogen oxides and carbon monoxide in the
combustion products.
[0046] FIG. 3 shows a possible embodiment of a drying arrangement
11 according to the invention. This may be part of a machine for
manufacturing or treating a material web. The drying arrangement 11
here is arranged behind a coating or binder section (not shown) of
the machine, in the running direction of the material web 8. Within
this section, a coating color or binder is applied to the material
web 8. As a result of this application, the material web 8 absorbs
moisture and must therefore be dried, or the binder must be cured.
This is done in the drying arrangement 11.
[0047] The drying arrangement 11 comprises one or, as shown here, a
plurality of infrared dryers 12, each of which respectively has a
multiplicity of infrared radiators 1 that serve as surface
radiators and are preferably arranged parallel to the material web
8. In addition, the drying arrangement 11 also has a plurality of
air dryers 13. In the present case, an infrared dryer 12 is
respectively downstream of an air dryer 13 when viewed in the
running direction of the material web 8, and so forth. Such an
infrared dryer 12 and air dryer 13 are respectively referred to as
a combination dryer 14. Four combination dryers 14 are furnished,
arranged one behind the other in the running direction of the
material web 8 to be dried. These combination dryers are, in this
case, arranged directly abutting one another. Consequently, when
the material web 8 to be dried leaves a first combination dryer 14,
it immediately reaches the following combination dryer 14 viewed in
the running direction. All combination dryers 14 are set up in such
a way that, viewed in the running direction of the material web,
drying occurs by infrared radiation from the associated infrared
dryer 12, then by convection through the corresponding air dryer
13, by heat radiation and so on alternatingly. As soon as the
material web 8 has left the first combination dryer 14 as viewed in
the running direction of the web, it is transferred to the second
combination dryer 14. There in turn, as viewed in its running
direction, the web is first dried by the corresponding infrared
dryer 12 and then by the corresponding air dryer 13. In other
words, an air dryer 13 assigned to the first combination dryer 14
is arranged between an infrared dryer 12 of a first combination
dryer 14 in the running direction and an infrared dryer 12 of
another combination dryer 14 immediately following it in the
running direction--viewed respectively in the running direction of
the material web 8 through the drying arrangement 11. One could
also say that the material web 8 is dried along the drying
arrangement 11 alternatingly by heat radiation, then by convection,
again in turn by heat radiation and so on.
[0048] The infrared dryer 12 of a respective combination dryer 14
may be designed as a gas-heated infrared dryer according to the
invention. In this case, the infrared dryer 12 may comprise one or
more infrared radiators 1 according to the invention (see FIGS. 1a
and 1b). The combustion products (exhaust gases) that the infrared
radiators 1 generate may then be extracted from the infrared dryer
12 via one or more suction nozzles 12.1 associated with the
infrared dryer 12, only one of which is indicated here in a purely
schematic manner. The at least one suction nozzle 12.1 may be
arranged inside a housing that surrounds the infrared dryer 12.
[0049] The respective air dryer 13 may comprise one or more blowing
nozzles 13.1, of which only one is shown here, likewise in a purely
schematic manner. The at least one blowing nozzle 13.1 serves,
among other things, to supply heated air to the material web 8 for
drying. For this purpose, the at least one blowing nozzle 13.1 may
be connected to a fresh air supply (not shown) in a flow-conducting
manner. In addition, a flow-conducting connection may be furnished
between the at least one suction nozzle 12.1 and the at least one
blowing nozzle 13.1 of the same combination dryer 14. The thermal
energy contained in the exhaust gas of the infrared dryer 12 may be
used to heat the fresh air or to dry the material web 8 using the
thermal energy of the exhaust gas of the respective infrared dryer
12.
* * * * *