U.S. patent application number 13/320795 was filed with the patent office on 2012-03-15 for method and apparatus for tempering material.
This patent application is currently assigned to BENEQ OY. Invention is credited to Sampo Ahonen, Reijo Karvinen, Tommi Vainio.
Application Number | 20120060536 13/320795 |
Document ID | / |
Family ID | 40825398 |
Filed Date | 2012-03-15 |
United States Patent
Application |
20120060536 |
Kind Code |
A1 |
Ahonen; Sampo ; et
al. |
March 15, 2012 |
METHOD AND APPARATUS FOR TEMPERING MATERIAL
Abstract
A method and apparatus for tempering material is provided. One
or more liquids are atomized by at least one sprayer into droplets
which are guided towards a surface of a hot material so that at
least some of the droplets collide with the surface of the hot
material and evaporate, thus removing thermal energy from the
surface layer of the hot material. Impact members may be used to
further reduce the size of the droplets. The droplets may be guided
to the surface by a separate guiding gas flow.
Inventors: |
Ahonen; Sampo; (Espoo,
FI) ; Karvinen; Reijo; (Tampere, FI) ; Vainio;
Tommi; (Soderkulla, FI) |
Assignee: |
BENEQ OY
VANTAA
FI
|
Family ID: |
40825398 |
Appl. No.: |
13/320795 |
Filed: |
June 15, 2010 |
PCT Filed: |
June 15, 2010 |
PCT NO: |
PCT/FI10/50499 |
371 Date: |
November 16, 2011 |
Current U.S.
Class: |
62/304 |
Current CPC
Class: |
C03B 27/02 20130101;
C03B 27/028 20130101; B05B 1/26 20130101; C03B 27/024 20130101;
C21D 1/667 20130101; B05B 7/045 20130101 |
Class at
Publication: |
62/304 |
International
Class: |
F28D 5/00 20060101
F28D005/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 18, 2009 |
FI |
20095695 |
Claims
1. A method for tempering material, the method comprising atomizing
at least one liquid into droplets, the formed droplets being guided
towards a surface of a hot material so that at least some of the
droplets collide with the surface of the hot material, wherein the
droplets are formed and guided to the surface of the hot material
in such a way that the droplets colliding with the surface of the
hot material evaporate when they receive thermal energy from the
surface layer of the hot material.
2. A method according to claim 1 of atomizing at least one liquid
being into droplets whose average diameter is smaller than equal to
30 um.
3. A method according to claim 1, wherein at least one liquid is
atomized into droplets whose average diameter is smaller than equal
to 10 um.
4. A method according to claim 1, wherein at least one liquid is
atomized into droplets whose average diameter is smaller than equal
to 5 um.
5. A method according to claim 1, wherein the at least one liquid
is atomized by means of a gas flow or ultrasound.
6. A method according to claim 5, wherein the atomizing gas flow is
used for guiding the droplets towards the surface of the hot
material.
7. A method according to claim 1, wherein the droplets are guided
towards the surface of the hot material using a separate guiding
gas flow.
8. A method according to claim 1, wherein the at least one liquid
is atomized into two or more droplet jets by guiding at least two
droplet jets substantially perpendicularly towards one another to
make the droplet jets collide directly with one another.
9. A method according to claim 1, comprising guiding a gas flow
from at least one direction to the collision point of the droplet
jets for forming an aerosol and for guiding it towards the surface
of the hot material.
10. A method according to claim 1, wherein the method comprises the
steps of atomizing at least one liquid raw material by at least one
gas dispersing sprayer into an aerosol that is released from the
spray end of the sprayer; decreasing the droplet size of the
aerosol released from the spray end of the sprayer by changing the
hydrodynamic properties of the aerosol flow by means of flow
impediments; and guiding the aerosol onto the surface of the
material so that at least some of the droplets in the aerosol
collide with the surface of the hot material and evaporate upon
receiving thermal energy from the surface layer of the hot
material.
11. A method according to claim 10, comprising reducing the average
droplet size in the aerosol by changing the hydrodynamic properties
of the aerosol flow by means of flow impediments so that the
aerosol droplets released from the spray end collide with one or
more flow impediments and/or one another to reduce the droplet size
of the aerosol.
12. A method according to claim 10, comprising reducing the average
droplet size in the aerosol by changing the hydrodynamic properties
of the aerosol flow by means of flow impediments so that they cause
a pressure change and/or a throttle in the aerosol flow released
from the sprayhead for reducing the droplet size.
13. A method according to claim 1, wherein the temperature of the
hot material before the tempering is 450 to 850 C..degree..
14. A method according to claim 1, wherein the hot material is a
glass, metal, metal alloy orceramie material.
15. A method according to claim 1, comprising using always water,
alcohol, mixture of water and alcohol, some other liquid mixture or
emulsion suitable for cooling.
16. An apparatus for tempering a material, the apparatus comprising
one or more sprayer for atomizing at least one liquid into
droplets, and means for guiding the formed droplets towards a
surface of a hot material so that at least some of the droplets
collide with a surface of the hot material, wherein the apparatus
is configured to produce droplets and to guide formed droplets to
the surface of the hot material so that the droplets collide with
the surface of the hot material in the form of droplets, the
droplets evaporating when they receive thermal energy from the
surface layer of the hot material.
17. An apparatus according to claim 16, wherein one or more
sprayers are configured to atomize at least one liquid into
droplets having an average diameter smaller than or equal to 30
um.
18. An apparatus according to claim 16, wherein one or more
sprayers are configured to atomize at least one liquid into
droplets having an average diameter smaller than or equal to 10
um.
19. An apparatus according to claim 16, wherein the at least one
liquid is atomized into droplets having an average aerodynamic
diameter smaller than or equal to 5 um.
20. An apparatus according to claim 16, wherein the apparatus is
configured to atomize at least one liquid flow by a gas flow or
ultrasound.
21. An apparatus according to claim 20, wherein the means for
guiding the formed droplets towards the surface of the hot material
comprise one or more gas flows atomizing at least one liquid.
22. An apparatus according to claim 16, wherein the means for
guiding the formed droplets towards the surface of the hot material
comprise one or more gas nozzles.
23. An apparatus according to claim 16, wherein at least two
sprayers are arranged substantially perpendicularly directed
towards one another so that the droplet jets they form collide with
one another perpendicularly.
24. An apparatus according to claim 23, wherein it comprises at
least one gas nozzle for supplying gas from at least one direction
to the point where the droplet jets collide for guiding the
droplets towards the surface of the hot material.
25. An apparatus according to claim 16, wherein the apparatus
comprises at least one gas dispersing sprayer for atomizing liquid
at the sprayer end of the sprayer into gas, the sprayer further
comprising one or more flow impediments for changing the
hydrodynamic properties of the aerosol flow released from the
sprayer end so that the average droplet size in the aerosol
changes.
26. An apparatus according to claim 25, wherein the sprayer
comprises a spray chamber with flow impediments formed therein and
in flow connection to the spray head.
27. An apparatus according to claim 26, wherein the flow
impediments have been formed onto the inner walls of the spray
chamber so that they protrude from the inner walls into the spray
chamber.
28. An apparatus according to claim 25, wherein the flow
impediments have been arranged so that the aerosol droplets
released from the spray end collide with one or more flow
impediments and/or one another for reducing the droplet size in the
aerosol.
29. An apparatus according to claim 25, wherein the flow
impediments have been arranged so that they cause a pressure change
and/or throttle in the aerosol flow released from the spray head
for reducing the droplet size of the aerosol.
30. An apparatus according to claim 16, wherein at least one
atomizing liquid used is water, alcohol, mixture of water and
alcohol or some other liquid mixture or emulsion comprising water
and/or alcohol.
Description
BACKGROUND OF THE INVENTION
[0001] The invention relates to a method according to the preamble
of claim 1 for tempering material and to apparatus according to the
preamble of claim 16 for tempering material.
[0002] According to prior art metals, such as steel, glass and
other materials are tempered by air cooling. It is also known to
temper a piece to be tempered by immersing the hot piece into
water. In tempering based on air cooling, a strong flow of air is
directed to the material to be tempered or to a surface of a
product. The strong flow of air is used with the aim of reducing
the temperature of the material rapidly, the structure and/or
properties of the material undergoing changes that provide the
material with desired characteristics. Steel tempering, for
example, is understood to mean heating the steel above the
temperature of austenite formation and cooling it, after a holding
period required for the austenite formation and homogenization, at
a rate faster that the critical cooling rate. The aim with the
tempering is a specific, predetermined martensite content in the
microstructure of the tempered piece. Glass tempering, in turn,
aims at using rapid cooling to produce a compression tension in the
surface layer of the glass and a tensile stress into the inner part
of the glass.
[0003] A problem with the above prior art solution based on air
cooling is that air cooling in connection with tempering requires
an extremely large amount of air and an efficient blow thereof
towards the surface of the material or product to be tempered. Such
a large amount of air and efficient blow consume extremely high
amounts of energy. Moreover, in many applications management of
rapid and uniform cooling is difficult to control and carry out,
particularly when thin pieces, such as thin glass, are being
tempered. Hence air cooling and the control thereof for producing
an even cooling requires complex hardware solutions. Water
tempering, in which a hot piece is immersed into water, is
impossible to control on an industrial scale when tempered products
of a good quality are to be produced.
BRIEF DISCLOSURE OF THE INVENTION
[0004] It is therefore an object of the invention to provide a
method and apparatus that allow the above problems to be solved.
The object of the invention is achieved by a method according to
the characterizing part of claim 1, characterized in that in the
method at least one liquid is atomized into droplets, the formed
droplets being guided towards a surface of a hot material so that
at least some of the droplets collide with the surface of the hot
material and evaporate when they receive thermal energy from the
surface layer of the hot material. The object of the invention is
further achieved by the apparatus according to the characterising
part of claim 16, the apparatus being characterized in that the
apparatus comprises one or more sprayers for atomizing at least one
liquid into droplets and means for guiding the formed droplets
towards a surface of a hot material so that at least some of the
droplets collide with the surface of the hot material and
evaporate, thus removing thermal energy from the surface layer of
the hot material.
[0005] The preferred embodiments of the invention are disclosed in
the dependent claims.
[0006] The invention is based on the idea of cooling a material or
product in tempering by using at least one liquid which is atomized
into small droplets by means of one or more sprayers. The droplets
are further conveyed to the surface of the hot material to be
tempered so that the droplets collide with the surface of the hot
material to be tempered. The droplets may be guided towards the
surface of the hot material by using a gas flow, the cooling of the
hot material being achieved by an aerosol that comprises the formed
droplets. The droplets colliding with the hot surface of the
material receive thermal energy from the hot material and evaporate
quickly. In other words, liquid evaporates in separate droplets and
from separate droplets so that no layer of liquid or pools
consisting of a plural number of droplets are formed onto the
material surface. In other words, when a droplet collides with the
surface of the hot material, it evaporates in the collision or
immediately thereafter. This is achieved by using sufficiently
small droplets. The liquid is preferably coalesced into droplets
having an average diameter smaller than or equal to 30 um. These
extremely small droplets evaporate rapidly as they collide with the
hot material, thus removing efficiently thermal energy from the hot
material. In a preferred case the power of the collision on the
surface of the hot material is sufficiently efficient for
evaporating small droplets substantially in connection with the
collision.
[0007] An advantage of the method and apparatus of the invention is
that the use of small droplets for cooling hot material in a
tempering process enables an energy efficient means for tempering a
hot material. The small droplets allow a rapid and efficient heat
transfer from a hot piece to be achieved. Uniform and rapid heat
transfer is particularly important when large surfaces and thin
products, such as thin glass, are to be tempered. Cooling produced
with small droplets consumes significantly less energy than prior
art air cooling and, moreover, a tempering apparatus based on the
use of small droplets has a structure that is simpler to
produce.
BRIEF DISCLOSURE OF THE FIGURES
[0008] In the following the invention will be disclosed in greater
detail in connection with preferred embodiments, with reference to
the enclosed drawings, in which:
[0009] FIG. 1 is a schematic view of the apparatus according to the
invention for tempering material;
[0010] FIG. 2 is a schematic view of a sprayer for carrying out
tempering according to the invention;
[0011] FIG. 3 is a schematic view of a second sprayer for carrying
out tempering according to the invention; and
[0012] FIG. 4 is a schematic view of a second embodiment of the
sprayer.
DETAILED DISCLOSURE OF THE INVENTION
[0013] Reference is made to FIG. 1, which discloses an embodiment
of the apparatus of the invention that allows the method of the
invention to be implemented. The apparatus 50 is used for tempering
a moving hot material web 26. The material to be tempered may be
for example metal, such as steel, glass, metal alloy or a ceramic
material. Although FIG. 1 shows the tempering of a moving material
web, the method and apparatus of the invention may be applied to
the tempering of any material or product movable in any way.
Alternatively, the material or product to be tempered may also be
stationary and one or more sprayers may move. In accordance with
the invention the apparatus 50 comprises a sprayer 22 that allows
the one or more liquids to be atomized into small droplets. When
necessary, the apparatus 50 may also comprise two or more sprayers
22. The liquid to be atomized with the sprayer 22 to be used in
tempering is preferably water, although it may also be an alcohol,
such as a mixture of ethanol, water and alcohol, or some other
liquid mixture or emulsion comprising water and/or alcohol.
Alternatively, it is also possible to use some other liquid
suitable for cooling or tempering or a mixture of one or more
liquids. The liquid to be atomized is conveyed to the sprayer 22 on
a line 2 through a flow meter 27. Also a gas flow is conveyed to
the sprayer 22 on a channel 20 and through a flow regulator 18. The
sprayer 22 shown here is a gas dispersing sprayer, although an
ultrasound sprayer or some other sprayer capable of producing
sufficiently small droplets is also possible. The sprayer 22
atomizes liquid into small droplets 7 which are led by means of the
gas flow, for example, towards the surface of the material web 26
to be tempered.
[0014] The sprayer 22 may be in a chamber 14, which substantially
separates the inner space of chamber 14 from the ambient
atmosphere. Inert gas, for example, may be supplied into the
chamber 14 from a gas conduit, which is preferably the gas conduit
20 used for atomizing the liquid. Alternatively, gas may be
supplied into the chamber 14 from separate gas nozzles. The chamber
14 may also be provided with suction means for removing evaporated
droplets 7 from the chamber 14. In other words, the apparatus 50
comprises means for guiding droplets 7 formed with the sprayer 22
towards the surface of the hot material 26. These means for guiding
the formed droplets 7 towards the surface of the hot material may
comprise one or more gas flows 20 atomizing at least one liquid, or
one or more separate gas nozzles (not shown). The heating of the
material to be tempered may take place in process step 24, for
example, which is arranged upstream of the sprayer 22 and may
consist of heating, working or a similar process step. In a
preferred embodiment the tempering apparatus 50 of the invention is
connected to a manufacturing or processing line of a material or
product, such as a flat glass manufacturing line, the manufacturing
line of some other glass product, the manufacturing line of steel
or to the manufacturing or processing line of some other product or
material. In the manufacturing line of flat glass the tempering
apparatus 50 may be placed after the tin bath in the float line,
for example, the temperature of the glass strip rising from the
bath being 650.degree. C. at the most. The temperature of the hot
material arriving at the tempering may be from 850 to 450.degree.
C., for example. However, the temperature depends on the material
to be tempered and the desired tempering properties.
[0015] In the disclosed invention hot material is tempered using
small droplets 7 to produce the necessary rapid cooling, the
droplets being guided to collide with the surface of the hot
material 26 so that the droplets 7 collide with the surface of the
hot material 26, as shown in FIG. 1. Sufficiently small size of the
droplets 7 allows them to be made to collide with the surface of
the hot material 26 at a sufficient speed. At the collision the
droplets 7 receive thermal energy from the material 26,
particularly from the surface layer thereof, and evaporate. To
create efficient and rapid cooling the droplets 7 need to be
sufficiently small. In order to provide sufficiently small droplets
one or more sprayers 22 are arranged to atomize at least one liquid
into droplets with an average diameter smaller than or equal to 30
um, preferably smaller than or equal to 10 um and more preferably
smaller than or equal to 5 um. According to an embodiment the
sprayer 22 has been achieved by producing droplets 7 with an
average diameter of less than 3 um, and preferably even droplets 7
of an average diameter of less than 1 um. If the droplets 7 are too
big, for example 100 um or more, the droplets 7 do not evaporate
rapidly enough when they collide with the surface of the hot
material 26 but form a liquid film onto the surface of the hot
material 26, or remain floating onto the surface of the hot
material 26. This slows down the cooling and the liquid film boils
away from the surface of the hot material 26, thus forming a gas
layer above the surface, which further slows down the cooling. The
liquid remaining onto the surface of the hot material 26 also
causes uneven cooling of the hot material 26 and uneven residual
stresses. Further, a liquid film or a large drop left on the
surface of the hot material 26 often leaves undesirable marks on
the material surface. In addition, the speed of the large droplets
often remains too low for a sufficiently efficient collision to be
achieved on the surface of the hot material 26. The small droplets
7 may be generated using a gas dispersing sprayer 22 or an
ultrasound sprayer, for example. However, a disadvantage with the
ultrasound sprayer is its low droplet prodktion rate and the need
for a separate control gas for guiding the droplets 7 towards the
surface of the hot material 26. In other words, for a good cooling
to be achieved the droplets are to be sufficiently small in order
to have a sufficiently small mass for a rapid evaporation and,
moreover, the droplets are to be guided towards the surface of the
hot material at a sufficient rate for an efficient collision to be
achieved. In the present invention the small size of the droplets 7
and their sufficient speed causes the droplets 7 to collide
substantially as separate droplets, thereby avoiding the formation
of a liquid film or pools onto the surface of the hot material. The
sufficient speed of the droplets 7 depends for example on the size
of the droplets 7 and on the liquid used for the cooling and for
forming the droplets 7.
[0016] The following shows by means of FIGS. 2, 3, and 4 examples
of alternative sprayers 22, with which sufficiently small droplets
7 may be produced.
[0017] FIG. 2 shows a basic view of the sprayer 22. Liquid, such as
water, used in tempering is fed into the sprayer producing
ultra-small liquid droplets from a channel 25. Spraying gas, such
as nitrogen IM2, is led to a gas channel 20. A distributing chamber
30 and flow impediments 32 distribute the spray flow evenly around
the liquid channel 25, whereby the liquid atomizes into droplets in
the spray nozzle 34. The droplet size of the aerosol atomized in
the spray nozzle 34, or spray head 34, is relatively large. As the
aerosol flows on, the flow impediments 36 alter the hydrodynamic
properties of the aerosol flow and unexpectedly cause the droplet
size of the aerosol to change into ultra-small droplets. The
mechanism is based on both collision energy and pressure change
caused by the flow impediments 36. In other words, the flow
impediments 36 are arranged in such a manner that the droplets of
the aerosol discharging from the spray head 34 collide into one or
more flow impediments 36 and/or each other to reduce the droplet
size of the aerosol. In addition or alternatively, the flow
impediments 36 are arranged in such a manner that they generate
into the aerosol flow discharging from the spray head 34 a pressure
change and/or restriction to reduce the droplet size of the
aerosol. With the arrangement, ultra-small droplets 7 discharge
from the nozzle. The ultra-small droplets are further directed to
the surface of the hot material 26. The droplets 7 evaporate as
they collide with the surface of the hot material 26 and remove
heat energy from the hot material 26.
[0018] According to what is stated above, the sprayer 22 of FIG. 2
atomizes at least one liquid into aerosol at the spray head 24 of
the sprayer 22 by means of gas. The sprayer 22 has at least one
liquid channel 25 for supplying at least one liquid to be atomized
into the spray head 34 and at least one gas channel 20 for
supplying at least one gas into the spray head 34 for spraying the
liquid into an aerosol. The spraying gas atomizes the liquid into
an aerosol in the spray head 34 especially as a result of the
difference in the velocity of the spraying gas and liquid
discharging from the spray head 34. The sprayer 22 also comprises
one or more flow impediments 36 for altering the hydrodynamic
properties, such as velocity and pressure, of the aerosol flow
discharging from the spray head 34 in such a manner that the
droplet size of the aerosol diminishes. The sprayer 22 may be
equipped with a spray chamber 35 in flow connection with the spray
head 34, to which spray chamber the flow impediments 36 are formed.
In FIG. 2, the spray chamber 36 is a tubular space, but may also be
some other space. There may be one or more flow impediments 36 and
they may be placed consecutively, side by side or in some other
corresponding manner in relation to each other. The flow
impediments 36 may for instance guide, slow, or restrict the
aerosol flow. According to FIG. 2, the flow impediments 36 are
provided on the inner walls of the spray chamber 34 in such a
manner that they extend from the inner walls toward the inside of
the spray chamber 34. Preferably, the flow impediments 36 are
arranged in such a manner that the aerosol droplets discharging
from the spray head 34 collide into one or more flow impediments 36
and/or each other to reduce the droplet size of the droplet spray.
In addition to or alternatively, the flow impediments 36 are
arranged to generate a pressure change and/or restriction in the
aerosol flow discharging from the spray head 34 to reduce the
droplet size of the droplet spray. By means of the flow impediments
36, the average aerodynamic diameter of the aerosol droplets
discharging from the sprayer 22 becomes 10 micrometers, preferably
3 micrometers or less, and more preferably 1 micrometer or
less.
[0019] FIG. 3 shows another sprayer 22 for generating small
droplets. Two sprayers 2 directed substantially at each other are
fastened to the body 1 of the sprayer 22. The sprayers 2 are
arranged into the device directly toward each other as shown in
FIG. 1. In other words, the sprayers 2 are preferably arranged
essentially coaxially opposite each other in such a manner that
their droplet sprays 4 essentially directly collide with each
other. The device may comprise two or more sprayers 2. Preferably,
the sprayers 2 are arranged in pairs to form one or more sprayer
pairs in such a manner that the sprayers 2 of each sprayer pair are
directed essentially directly, preferably coaxially, toward each
other, whereby the droplet sprays 4 or each sprayer pair collide
directly with each other. The sprayer pairs may further be arranged
into the device for example consecutively or side by side in the
vertical or horizontal direction.
[0020] A liquid 3 to be sprayed and spraying gas 8 are fed into the
sprayer 2. The spraying gas 8 and liquid 3 are preferably fed into
the sprayer 2 at different velocities, whereby the difference in
velocity between the spraying gas 8 and liquid 3 at the output of
the sprayer 2 cause the liquid 3 to spray, atomize, into a droplet
spray 4 that consists of small droplets. The droplet sprays 4
collide with each other, whereby an aerosol consisting of very
small droplets 7 is unexpectedly formed. The droplet spray 4 may in
itself already form an aerosol. As droplet sprays directed
essentially directly at each other collide, an aerosol is produced
that does not essentially move, when the momentums of the droplet
sprays 4 are essentially equal. The device may further be arranged
to contain means for supplying at least two different liquids to at
least two sprayers. In other words, the device may be formed in
such a manner that the same or different liquids may be supplied to
two or more sprayers 2. In other words, the same or different
liquids may be supplied to the sprayers 2 of each sprayer pair, if
desired. In addition, the same liquid as or different liquids than
in the other sprayer pairs can be used in at least two sprayer
pairs. In such a case, each sprayer pair may produce a different
spray or a similar spray as the sprayer pair beside it. Further,
the sprayers 2 of the device may be adapted to produce droplet
sprays 4 in which the droplets are substantially different or
similar in their average droplet size. For instance, the geometry
of the sprayers 2 or the velocity of the fluid 3 and spraying gas
or the difference in velocity between them may all affect the size
of the droplets. This makes it possible to produce an aerosol that
is homogeneous or heterogeneous in droplet size.
[0021] The sprayer 22 preferably also comprises means for directing
a gas flow from at least one direction to the collision point of
the droplet sprays 4. This is preferably done by furnishing the
device with a gas nozzle 5 for supplying gas from at least one
direction to the collision point of the droplet sprays 4. Thus, by
means of the gas flow, it is possible to move or transfer the
aerosol generated at the collision point of the droplet sprays 4
into a required direction toward the surface of the hot material
26. Any gas may be used in the gas nozzle 5. In other words, it may
be an inert gas, such as nitrogen, or a gas that reacts to the
spray or aerosol. In the embodiment of FIG. 3, the gas nozzle 5 is
arranged into the device in such a manner that the gas flow flows
and collides substantially perpendicularly in relation to the
droplet sprays 4.
[0022] Another embodiment of the sprayer 22 of FIG. 3 is shown in
FIG. 4. Two sprayers 2 directed substantially at each other are
mounted on the body 1 of the sprayer 22. A liquid 3 to be sprayed
and spraying gas 8 are supplied to the sprayer 2. The difference in
velocity between the spraying gas 8 and liquid 3 at the output of
the sprayer 2 makes the liquid 3 atomize into droplet sprays 4 that
comprise small droplets. The droplet sprays 4 collide with each
other, whereby an aerosol made up of very small droplets 7 is
unexpectedly formed. From a sprayer 12 fastened to the body 1 of
the sprayer 22, a liquid 10 and atomizing gas 11 (together:
aerosol) are also supplied to the collision point of the droplet
sprays 4. The atomizing gas 11 then acts as a spraying gas for the
liquid 10. The aerosol discharging from the sprayer 12 guides the
formed droplets on toward the surface of the hot material 26.
[0023] It is apparent to a person skilled in the art that as
technology advances, the basic idea of the invention may be
implemented in many different manners. The invention and its
embodiments are, thus, not limited to the examples described above,
but may vary within the scope of the claims.
* * * * *