close

Вход

Забыли?

вход по аккаунту

?

Патент USA US3071875

код для вставки
Jan. 8, 1963
H. W. FAEBER '
3,071,865
WEB DRYER
Filed Jan. 30, 1958
5 Sheets-Sheet 1
mwuim
m
1“
A
WY NTm. m?
H
MKQ, Mn
w.
s
m
Jan. 8, 1963
H. w. FAEBER
.
3,071,365
WEB DRYER
3
Filed Jan. 30, 1958
5 Sheets-Sheet 2
FIG. 2.
v -
M
AW
- 4%
»
‘TEMPERATURE
DISTRIBUTED
‘
Y
RECIRCULATED AIR
RESULTING
6
UNIFORM
-
TEMPERATUR
TEMPERATURE DISTRIBU
WITHOUT RECIRCULATIO
N
4/
H 4?
I]
I I l hl l40”’
l I I I”
_
ROOM TEMPERATURE
r——_—
FIG. 3.
l-— was
INVENTOR.
WIDTH —-————_l
FIG. 4.
HARRY w. FAEBER
BY ELTf‘ZéiT;
his
ATTORNEYSv
Jan. 8, 1963
H. w. FAEBER
' '
Filed Jan. 30, 1958
3,071,365
WEB DRYER
5 Sheets-S?eet 5
5.FIG.
TOR;
HARRY w. FAEBER
his
A TTORNEYS.
Jan. 8, 1963
3,071,865
H. W. FAEBER
‘WEB DRYER
Filed Jan. 30, 1958
5 Sheets-Sheet 4
his
A TTORNEYS
Jan. 8, 1963
H. w. FAEBER
3,071,855
WEB DRYER
Filed Jan. 30, 1958
5 Sheets-Sheet 5
FIG. 8.
INVEN TOR.
HARRY
BY
w. FAEB ER
I 1"“ .
GEM 4' ‘pa-140K
his
ATTORNEYS‘
United States atent f?ce
‘
1
3,071,865
Harry W. Faebcr, Larchmont, N.Y., assignor to ‘Time,
WEB DRYER
Incorporated, New York, N.Y., a corporation of New
York
Filed Jan. 30, 1953, Ser. No. 712,185
7 Claims. (Cl. 34-62)
The present invention relates to an apparatus for use
in drying materials in web form, and particularly to appa
ratus for use in drying printed Web material at high
speeds.
'
During the past several years, various devices have
been developed for drying rapidly moving webs and these
have been found to be of considerable utility in the print
ing, paper, photographic ?lm and textile industries. These
devices generally employ the principle of rapidly moving
3,071,865
Patented Jan. 8, 1963
2
{for reducing the total amount of heat required in operat
ing a web drying mechanism.
'
'
'
Still another object of this invention is to reduce the
amount of air drawn from the press-room, thus reducing
the air conditioning or air heating load on the pressroom
ventilation system.
>
i
‘
These and further objects of the invention are accom
plished by disposing a suitable air distributing duct above
a rapidly moving web being dried by heating means such
as gas burners. The air directing duct has means therein
for regulating the amount of air distributed to different
portions of the web transversely thereof. The regulating
means are designed to furnish air to the web where re
quired, in order to provide a temperature curve which,
when combined with a temperature curve resulting‘from
the primary heating means, minimizes temperature vari
ations across the web and affords a desirable temperature
the web to be dried through a chamber of heated air.
curve across the width of the web.
'
The temperature of the air in the chamber is generally
In a preferred embodiment of the invention, the heated
very high and if the web‘ were to be exposed to such tem 20
air directed to the web is provided by withdrawing heated
perature for a substantial period of time, burning or char
air from the drying chamber adjacent one of the heating
ring of the web would occur. However, because of the
means and recirculating it to the distributing duct. The
short time of contact, the high temperature air serves
amount of air furnished to the distributing duct is su?i
only to evaporate the solvent or other volatile material
cient to substantially equalize the pressure between the
from the web.
inside and outside of the burner box in order to reduce
‘One of the principal problems in devices of this nature
has been the realization of a uniform temperaturegradii . any tendency for air to leak into this enclosure. How
ever, it is preferable to maintain a slightly decreased pres—
cut across the entire surface of the web; Gas or oil. burn
sure in the burner box to prevent the leakage of fumes
ers are generally employed as a source of heat, and the
therefrom.
products of combustion, together with heated airand sol 30
In a further preferred embodiment, the heated air is
vent vapors,‘ will follow the web either concurrently or
withdrawn from adjacent the center line of the drying
countercurrently, depending on the nature of the appa
chamber and recirculated to a distributing duct. This has
ratus. In order to prevent escape of the noxious prod
the effect of further reducing the temperature in the cen
ucts of combustion as well as the volatilized solvents, the
tral portion of the web and, when used in combination
web drying devices are enclosed, the interior of the dryer
with the means for regulating the amount of air returned
being maintained at a pressure slightly below/atmospheric.
to the web transversely thereof, provides a very effective
This has created the additional problem of air leakage
and easily regulated means for obtaining a desirable tem
along the edges of the web being dried, with attendant
perature curve having minimum variations across the
impairment of the drying operation in these regions. -At
width of the web.
'
tempts at mechanically sealing these sources of air leak
An additional feature which may be employed in the
age have proven ineffective because of the necessity of
dryer of this invention is means for ?owing recirculated
maintaining running clearance between the edges of the
air over the top of the dryer enclosure before distributing
web and the enclosure, means of entry into the interior
the air across the web. In this manner the enclosure is
of the dryer for purposes of repair and maintenance, and
cooled and the heat thus obtained is returned to the dry-.
entry and exit of ‘the running web. Where the air leak
chamber. Furthermore, means may be employed for
age is cornpensated for by increasing the drying tempera 45 ing
withdrawing and exhausting to the atmosphere a portion
ture, scorching of the central portion of the web tends
of the recirculated air after its passage across the top of
to occur.
.
the
dryer enclosure, but before its introduction into the
_An additional di?'iculty involved in the use of presently
available web drying apparatus is the large amount of heat 50 drying chamber. Similarly, the recirculated air may be
caused to flow over the burners to cool the same. Also,
In
adjustable elements such as louvers or nozzles may be
order to reduce the air-conditioning requirements of the
employed
to direct the recirculated air to the surface of
room in which the dryer is located, it is necessary to re
the web.
duce the amount of makeup air entering the dryer‘from
These and further objects and advantages of the in
the pressroom to replace the exhausted air, and to pro 55 vention will be more readily understood when the follow
vide some means of cooling the exterior surface of the
ing description is read in connection with the accom~
dryer, particularly the top surface thereof. Conventional
panying drawings in which:
top surface cooling means include a water-jacketed top
lost by radiation as well as in the exhaust stack.
FIGURE 1 is a View in perspective of a typical web'
portion, and the heat thus removed constitutes a further
drying
system in accordance with the principles of the
loss of energy from the system.
‘
It is therefore an object of the present invention to 60 present invention;
FIGURE 2 is a longitudinal section of a heating hood
provide a means of obtaining an even temperature across
a moving web during drying thereof.
It is another object of the invention to provide a sys-'
duct constructed in accordance with the principles of
the present invention;
‘‘
FIGURE 3 is a view in section of a portion of the
tem of the above character in which heated air is directed’ 65
apparatus shown in FIGURE 2 taken along‘ line 3
to a burner enclosure to equalize temperatures across the‘
web.
and looking in the direction of the arrows;
' i.
It is a further object of the invention to provide a sys
FIGURE 4 is a schematic diagram showing the im
tem of the above character in which hot air is withdrawn
proved temperature distribution across the web obtained.
from a Web ‘heater and subsequently directed to the web
.
70 with the apparatus of this invention;
to equalize temperatures thereacross.
FIGURE 5 is a View in perspective of one modi?ca
Another object of this invention is to provide means
tion of the web dryer of this invention;
. . . 1 . . .
3,071,865
3
FIGURE 6 is a view in longitudinal section of the dry
er shown in FIGURE 5 taken along ‘the line 6—6 and
looking in the direction of the arrows;
FIGURE 7 is a view in section of the apparatus of
FIGURE 6 taken along the line 7—7 and looking in the
direction of the arrows; and
FIGURE 8 is a partial longitudinal section of a fur
4
46 are attached to vanes 47 by means of straps 49. The
straps 49 join the elements so that the vanes 47 may be
moved to any desired position and will be frictionally
retained there. In this manner recirculated air furnished
to the hood may be distributed to the web 10 in any de
sired manner.
In operation, the rapidly moving web v10 is heated
ther modi?cation of the apparatus shown in FIGURE 5.
when passing under the burner boxes 18, 19 and 20 and
Referring to a typical embodiment of the invention
the boundary layer of air travelling with the web is sep
in greater detail with particular reference to FIGURE 10 arated therefrom by the divergent blade 26 and exhaust
1, a web .10, with wet ink on its top side, having been
chamber 27. Heated air from above the center of the
just printed at a printing station, not shown, travels in
web 10 is withdrawn through air ducts 29, 30 and 31, the
the direction indicated by the arrow 11 over rolls 12,
duct 32, and pumped by the recirculating fan 33 through
13, '14 and 15 to direction shifting roll 16. The rolls 12
the ducts 38, 40, 41 and 42 to the hoods 43 and 44. The
to 16 are water cooled and supported by any conven
total amount of air circulated may be controlled by con
tional structure, .not shown in the interests of clarity.
ventional dampers (not shown), located in ducts 36, 37
Three burner boxes 18, 19 and 20 to which are respec
and 38. The air from the hoods entering the burner
tively joined connecting hoods 21, 22 and 23 house a
boxes 19 and 20 is distributed by adjustment of vanes
plurality of ceramic cup radiant gas burners 24 (FIG.
47 across the web 10 to provide a temperature curve B,
2) positioned along and extending laterally across the 20 shown in FIGURE 4, which represents the approximate
web 10. According to established practices, the supply
temperature distribution over the web that would prevail
of fuel :to the burners 24 is controlled in accordance with
the speed of the moving web 10 to heat the web to a
predetermined temperature and to preclude scorching
due to the recirculated warm air without burners.
Since
the recirculated air introduced into the drying chamber
is heated to a lower temperature than the exhausted air,
thereof. The burners 24 are mounted for rotation .in
the usual manner so that they are automatically turned
away from the web 10 when the web movement is stopped.
While the burner boxes and hoods enclose the web
' greater amounts of such air are furnished to the web
air leakage causes uneven heating of the web, as described
above. Such air leakage will be increased where a dry
ing system such as that disclosed in copending applica
sure is maintained in the burner boxes to prevent the
escape of noxious fumes.
It will be observed that the schematic curves A and B
as presented in FIGURE 4 are not exact complements.
The reason they provide a ?at curve C is due to the change
center to reduce the temperature of that area. When
the curves A ‘and B are combined, a resultant curve C
is provided illustrating the ?at temperature distribution
across the web 10, promoting rapid and even drying with
10, longitudinal openings 25 between the vertical sides
of the burner boxes and connecting hoods permit cold 30 out scorching. The fact that the extremes of the curve
C drop off slightly indicates that a slight negative pres
air to leak into the enclosed areas above the web 10. This
tion Serial No. 491,059, ?led February 28, ‘1955, for Web
Drying Methods and Apparatus, is utilized.
More particularly, a divergent blade 26 adjacent to
in pressure in the burner boxes which greatly reduces
the roll 16 cooperates with the burner boxes 18, 19 and
the amount of cool air drawn in along the edges of the
web 10.
20, connecting hood 23 and an exhaust chamber 27 to
provide a heated drying chamber in which a rapid air ?ow 40
Another embodiment of this invention is shown in
in the direction of web movement is built up and reaches
FIGURE 5. In this embodiment, the means for support
maximum velocity as it passes from the connecting hood
ing and moving the printed web 10 is similar to that
23 under the blade 26 into the exhaust chamber 27, where
described in copending application Serial No. 491,059,
it is exhausted by means of a duct 28 leading to an ex
mentioned above. More particularly, this means includes
a supporting roll 50 and direction shifting rolls 51, 52, 53
haust fan (not shown).
Exhausting air at a high rate from the exhaust cham
and 54. Roll 51 is a cooling roll, and roll 52 is a vacuum
ber 27 results in substantial air leakage through the
roll. In addition, suitable means (not shown) may be
spaces 25. Accordingly, absent the introduction of air
provided for rotating the rolls to drive the web 10 in
accordance with conventional practice in the art.
into the drying chambers, the temperatures across the
web 10 will be as shown in curve A of FIGURE 4, the 50
A plurality of line gas burners 55, 56 and 57 are sup
temperatures at the web edges being relatively low and
ported in any desired manner extending laterally across
the temperatures in the middle of the web being rela
the top of the web 10. According to established practice,
tively high.
the burners 55-57, inclusive, are controlled in accordance
Branch recirculating air ducts 29, 30 and 31 withdraw
with the speed of the moving web 10 to heat the surface
air from the center of the connecting hoods 21, 22 and 55 thereof to a predetermined temperature.
23 and direct it to a main recirculating air duct 32.
The moving web 10 and the supporting roller 50, to
Duct 32a, a main recirculating air duct from a further
gether with the burners 55-57, inclusive, are enclosed
dryer (not shown), connects with duct 32. A recirculat
by a suitable hood structure comprising insulated bottom
ing fan housing 33, the fan being driven by a motor 34
and side portions 58 and 59, respectively, and a top por
through a belt drive 35, is joined to the duct 32 and in
tion 60. An opening 61 in the hood structure is main
cludes an output duct 36 divided into two branches 37
tained to allow entrance of the moving web 10.
and 38. The branch 37 is for exhaust purposes while
An exhaust chamber 62 is positioned adjacent the
the branch 38 is further divided into branches 39 and
roll 51 and a divergent blade 63 is positioned above the
40, the branch duct 39 leading to the (further dryer (not
roll 51 and adjacent the Web 10 to create a turbulence in
shown).
65
the Zone of air surrounding the moving web, as described
Recirculated air is directed from the duct 40 through
in copending application Serial No. 491,059. A second
branch ducts 41 and 42 into hoods 43 and 44, respec
tively, distributing air across the web 10 passing through
divergent blade 64 is supplied adjacent the vacuum roll
52, and a second exhaust chamber 65 is positioned imme
the burner boxes 19 and 20 in a predetermined manner to
minimize temperature variations across the web.
70 diately adjacent the divergent blade 64 and the vacuum
Examining a typical hood 43 in greater detail with
reference to FIGURE 2, a divergent section 45 communi
cates with a distributing portion 46 in which are a plu
rality of adjustable elements ‘such as vanes 47. Pins
48 fastened at each end to the sides of the hood portion
roll 52.
The exhaust chambers 62 and 65 are ?tted with suitable
conduits 66 and 67, respectively, which are in turn con
nected with a blower 68 and an exhaust stack 69. The
blower 68 serves to withdraw the exhaust fumes from
8,071,865
6
the exhaust chambers 62 and 65 and direct them out of
the drying room through the stack 69.
The novel exhaust air recirculation system of this em
bodiment of the invention comprises a main duct 70
leading from the exhaust stack 69 to a plurality of dis
drying system through the exhaust stack 69. A separate air
recirculating system including a recirculating fan (not
shown), ducts 70 on the discharge side of the recirculat
ing fan, hoods 71 and 71a, cooling chambers 74 and
74a, and ducts‘ 81, 82 and 83, is employed. The ex
pensing hoods 71, each situated directly above a portion
of the dryer to be cooled by the recirculated exhaust gases.
haust gases are removed from the drying chamber through
duct 81 by means of the recirculating fan (not shown)
A plurality of dampers 72 and 73 are provided in the
and returned to the recirculation system through ducts
exhaust stack 69 and the duct 70, respectively, to‘regulate
70, 71 and 71a and the cooling chambers 74 and 74a.
the flow of recirculated air. The hoods 71 lead to a 10 The recirculated air passing through the cooling cham
cooling chamber 74 situated directly above the top sur
bers cool the top of the dryer. If desired, a portion of
face of the dryer and having a common wall therewith
the recirculated air may be withdrawn through ducts 81
to facilitate heat transfer between the chambers. At‘the
after its cooling function is completed and exhausted
end of the cooling chamber 74 remote from the hood 71,
through the recirculating fan. On the other hand, duct
an opening 75 is provided that communicates directly
81 maybe closed by means of suitable dampers 84, and
with the drying chamber 76, as shown in FIGURE 6.
the recirculated air directed upon the Web. In this case,
The opening 75 extends laterally, spanning the entire
width of the moving web 10 and contains a louver 77
the distribution of the recirculated air across the web
will be regulated by adjustment of vanes 79, as described
which‘is positioned so as to direct the recirculated exhaust
with relation to FIGURES 1 and 5. When necessary,
gases across the surface of moving web 10. Suitable in 20 additional quantities of air may be drawn into the inde
sulation 78 completely encloses the entire exhaust air
pendent air recirculation system through the intake side
recirculation system. a
'
of the recirculating fan, from the exhaust side of fan 68
Disposed within the cooling chamber 74 adjacent the
by means of a branch duct from duct 69.‘ In order to
’ opening 75 are a plurality ofvanes 79 which may be of
prevent a buildup of the volatile exhaust gases in the
the same design as the vanes 47 of FIGURE 1. The 25 recirculation system, a portion of the recirculated gases
vanes 79 may be placed in any desired position to regu
late the ?ow of recirculated air to minimize temperature
variations across the web 10.
Hood 71a and cooling chamber 74a, which feed re
circulated air across the ?rst section of the dryer and the
burners 55 and 56, are of somewhat different design.
Cooling chamber 74a has a plurality of openings 75a to
the drying chamber 76. In order to control the distribu
tion of the recirculated air across the web, the vanes 79a
are disposed in separate passageways 80 formed by suit 35
is exhausted to the atmosphere, as shown in the recircula
tion system of FIGURE 1.
'
It will be understood that the above-described embodi
ments of the invention are illustrative only and that modi~
?cations will occur to those skilled in the art. There
fore, the invention is not to be limited to the speci?c
apparatus disclosed herein but is to be de?ned by the ap~
pended claims.
I claim:
able partitions in the hood 71a and the cooling chamber
1. Drying apparatus for moving webs comprising a
drying chamber extending across and communicating
74a as shown in FIGURES 5 and 7.
with one side of the web, the sides of the chamber being
.
In operation of the dryer embodiment shown in FIG
URE 5, the moving web 10 is heated when passing under
the burners 55, 56 and 57 and the exhaust gases are re
moved through exhaust chambers 62 and 65 to exhaust
stack 69. The stream of exhaust gases is divided, a por
tion‘ being exhausted to the atmosphere and a portion
spaced from the Web sides, web heating means in the
40
being recirculated through duct 70, hoods'71 and 71a,
through the cooling chambers 74 and 74a and openings
75 and 75a into the drying chamber 76. The air entering
the drying chamber is distributed in any desired manner
to minimize temperature variations across the web 10 by
adjustment of vanes 79 and 79a.
An alternate embodiment of the novel air recircula
tion system of FIGURE 5 is shown in FIGURE 8. This
feature comprises means for withdrawing a portion of
the recirculated air at a point immediately prior to its
introduction into the drying chamber and after it has
passed over and cooled the top of the dryer, in combina 55
tion with an independent air recirculation system. A
duct 81 communicating with the cooling chamber 74 is
mounted on said cooling chamber at a point adjacent the
opening 75, but offset slightly therefrom. The duct 81
leads to an auxiliary duct 82 which in turn communicates
with a recirculator fan (not shown). In addition, a sec
ond duct 83 communicating with the drying chamber 76
and with the auxiliary duct 82 is adapted to withdraw
exhaust gases from the drying chamber. Both the re
chamber, means to exhaust heated air from the chamber
which creates a pressure below atmospheric in the dry
ing chamber and causes air to ?ow into the chamber
through the spaces between the chamber sides and the
web sides toward the center of the web, such air flow
tending to create an uneven temperature distribution
across the web with the web center at a high tempera
ture relative to the web side temperature, means to in
troduce air into the drying chamber to raise the pressure
therein and reduce the pressure ditferential between the
drying chamber and the atmosphere, and means to dis
tribute the introduced air nonuniformly across the web
under the chamber in a pattern to compensate for the
uneven temperature distribution and minimize tempera
ture variations across the web.
2. Apparatus as de?ned in claim 1, wherein said means
to introduce air comprises a duct, and said means to dis
tribute the introduced air comprises adjustable elements
to control the distribution pattern of the air across the
web.
3. Apparatus as de?ned in claim 1, in which means
are provided to recirculate at least a portion of the ex
haust air and use it for at least a portion of the air intro
duced into the drying chamber.
4. Drying apparatus for moving webs comprising a
drying chamber extending across and communicating with
circulated air from duct 81 and the exhaust gases from '
one side of the web, the sides of the chamber being spaced
duct 83 are returned to the recirculating fan (not shown), 65 from the web sides, web heating means in the chamber,
whose intake side may also be connected to the discharge
means to exhaust air from the drying chamber which
side of the divergent blade exhanst fan 68 shown in FIG
causes air to flow into the chamber through the spaces
URE 5 by means of a branch duct from duct 69. Thus,
between the chamber sides and the web sides, a cooling
the recirculating ‘fan receives air from three‘ kinds of 70 chamber outside of and parallel to the drying chamber,
sources; the cooling chambers 74, the exhaust duct 83,
a wall common to the cooling chamber and the drying
and the branch of the divergent blade exhaust.
chamber, the common wall being cooled by the cooling
In the operation ‘of this embodiment and referring
chamber to reduce heat radiation from the drying cham
to FIGURES‘ Sand 8, the exhaust gases removed from
ber, means to recirculate at least a portion of the ex
the exhaust chambers 62 and 65 are removed from the 75 .rhaust air through the cooling chamber, and means to
3,071,885
7
introduce at least a portion of the recirculated air into
the drying chamber to raise the pressure therein and
reduce the pressure differential between the drying cham
ber and the ‘atmosphere.
5. Apparatus as de?ned in claim 4, in which is provided
means to vwithdraw a portion of the recirculated air from
8
above and adjacent to the drying chamber, means for re
circulating air through the cooling chamber and into
the drying chamber to reduce heat radiation from the
drying chamber, means for selectively withdrawing pre
determined amounts of air from the cooling chamber,
from the drying chamber adjacent the web and from the
means for removing a boundary layer of air from the
Web outside of the drying chamber, and means for re
the cooling chamber after its cooling function has been
completed and prior to its introduction into the drying
chamber.
turning the cooling chamber air, the drying chamber air
v6. In ‘web drying apparatus, a drying chamber adapt 10 and the boundary layer air to the intake side of the re
ed to receive a moving web, the drying chamber includ
circulating means.
ing heating means to dry the moving web, a cooling
References Cited in the ?le of this patent
chamber outside the drying chamber and parallel to the
moving web, a wall common to the cooling chamber and
the drying chamber, the common wall being cooled by 15
the cooling chamber to reduce heat radiation from the
UNITED STATES PATENTS
drying chamber, means for recirculating air through the
1,676,091
2,022,593
Kemp ________________ __ July 3, 1928
Fuykers ______________ __ Nov. 26, 1935
cooling chamber into the drying chamber, and means for
selectively withdrawingair from the cooling chamber and
from the drying chamber in predetermined amounts and
returning the air to the intake side of the recirculating
2,183,298
2,204,802
2,229,285
2,268,988
Otfen ________________ __ Dec. 12,
Gessler ______________ __ June 18,
Gehnrich ______________ __ Jan. 21,
Hess et a1. ____________ __ Jan. 6,
1939
1940
1.941
1942
means.
2,330,395
2,803,446
2,837,830
2,921,778
2,929,153
2,939,222
Sullivan ____________ __ Sept. 28,
Flynn ______________ __ Aug. 20,
'Fry et a1. ____________ __ June 10,
Ruif ________________ __ Jan. 19,
Fry et al. __________ __ Mar. 22,
Svarar et a1. __________ u- June 7,
1943
1957
1958
1960
1960
1960'
7. In web drying apparatus, a drying chamber adapted
to receive a moving web, the drying chamber including
heating means to dry the moving web, means for re 25
moving a boundary layer of air from the web after the
web has left the drying chamber, a cooling chamber
Документ
Категория
Без категории
Просмотров
0
Размер файла
883 Кб
Теги
1/--страниц
Пожаловаться на содержимое документа