Note: Descriptions are shown in the official language in which they were submitted.
The present invention is the divisional of ayplication Serial No.
247,502, filed March 9, 1976, and relates to a method and an apparatus for
continuously manufacturing a sheet of layered food material, which is to be
generally subjected to subsequent stretching and folding operations to give a
food product having a desired number of layers, such as pies and Danish pastry.
In the past, when multi-layered food products containing dough such
as pies and Danish pastry are manufactured, dough is first stretched to form
a thin strip, lumps of oil products such as butter and margarine are placed
thereon and are wrapped up with the strip of dough on which they are placed,
then the dough strip folded up with the oil products therein are stretched and
folded into a couple of folds, and this stretching and folding step is repeat-
ed to give a sufficient number of layers required for the end products.
In the above conventional method, whether it is carried out manually
or mechanically, oil products are directly wrapped up with dough strip at the
initial stage. This brings about a defect in that the thickness of dough in
the end product tends to be uneven. Again, the operation itself is cumbersome
and time-consuming because operation is conducted manually in most cases.
In order to obviate such disadvantage and meet the requirements for
the end products, a starting material therefor was prepared by extruding it in
the form of a solid continuous cylindrical rod, of which the outer part consists
of dough and has a substantially even thickness in cross-section, and the core
part consists of oil products. However, when the cylindrical rod thus obtained
is pressed, and flattened in the form of a sheet, the non-layered parts at the
opposite ends contain far greater amounts of dough in comparison with the
upper and lower portions of the sheet.
Again, there has been no effective device in the past to press and
stretch dough material piled up in more than three layers. Thus, in order
to obtain a 27-layered dough product, it was necessary to fold a dough sheet
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in three layers and stretch the three-layered dough material and to repeat
this folding-stretching operation two more times. If the above operation
was to be performed on a conveyor system, the total length of the folding-
stretching device required more than 10 meters, occupying a large operational
space.
In Canadian Patent Application Serial No. 105,946, spherical dough
materials each containing a core material other than dough are fed onto a
movable base and below a press ram, which compresses the fed materials in
synchronization with the feed of the materials so as to produce multi-layered
food product.
In Canadian Patent Application Serial No. 217,37~ spherical dough
materials each containing a core material other than dough are fed into a
guide plate and a roller assembly consisting of a group of rollers freely ro-
tatable about their axes and revolving along a closed orbit, and the materials
thus fed are introduced into a space between a horizontal conveyor belt and
the lower straight portion of said closed orbit, whereby the materials are
stretched and flattened in such a manner that a sheet material consisting of a
plurality of horizontal layers of dough and other materials is obtained.
These inventions have resolved the above difficulties in the conven--
tional processes. However, they required manufacture of spherical dough mate-
rials comprising core material to produce ~ulti-layered dough materials, and
the formation of the layers in the end product was accomplished by compressing
said sphereical dough materials. In these cases, there was a certain limitation
in efficiency deriving from the use of such spherical materials. Further,
in the first mentioned application, compression by the action of a press some-
times tended to injure the dough tissue. In the second application, the use
of a single stretcher resulted in difficulty in obtaining a large number of
layers in the end product.
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According to one aspect of the invention, there is provided
a method of continuously manufacturing a flattened layered food
material, comprising the steps of feeding out of a feeder or ex-
truder continuously and simultaneously two kinds of food materials
in the form of a hollow tube consisting of two layers, transferring
the hollow tube onto a continuously driven conveyor means thereby
to allow it, while progressing on said conveyor means, to con-
tinuously collapse by gravity on said conveyor means, and flattening
the collapsed hollow tube on said conveyor means.
In an embodiment of the method, multi-layered dough
materials containing dough layers can be manufactured by the steps
of continuously extruding material in the form of a hollow tube
having two layers, allowing the tubular material to collapse flat
under its own weight on a continuously travelling conveyor, stretch-
ing the flattened material to a thin strip, folding and piling up
the strip of material to a predetermined number of multi-layers,
and re-stretching the piled material to a desired thickness.
Thus, it is possible to manufacture continuously and
automatically multi-layered dough materials containing thirty layers
or more of dough or dough and other material orderly arranged there-
in without injuring the dough tissue. Further, the present in-
vention enables the manufacture of multi-layered dough materials
comprising layers of dough and fat or oil such as butter overlapping
alternately without the problem of butter being squeezed out or
dough adhering to adjacent machine portions during a stretching
operation.
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~1~6~ 3
A further aspect of the present invention provides an
apparatus for continuously manufacturing a flattened layered food
material, comprising a feeder or extruder for feeding continuously
and simultaneously ~wo kinds of food material in the form of a
hollow tube consisting of two layers, and a continuously driven
conveyor means adapted to receive and convey the tube thereon there-
by to allow it, while progressing on said conveyor means, -to con-
tinously collapse by gravity on said conveyor, and means for
flattening the collapsed hollow tube on said conveyor means. The
apparatus optionally includes means for folding the flattened
hollow tube.
In one embodiment, said feeder comprises a vertical hollow
outer cylinder having an opening for receiving dough at the side
wall thereof, a vertical hollow screw arranged within said outer
cylinder so as to rotate about its own axis which is substantially
aligned with the axis of said outer cylinder thereby to feed down-
wards dough between the outer surface of said screw and the inner
surface of said outer cylinder, the hollow screw providing a
passage for allowing a food material other than dough to pass
therethrough, a nozzle having an annular lower end which is arranged
integrally with said hollow screw at the bottom thereof, said end
defining an annular orifice for discharging dough in cooperation
. with the inner surface of the lower end of said outer cylinder, and
a plug means arranged within the lower end of said nozzle so that
the peripheral surface of the lower end of said plug means defines
an annular orifice for said food material other than dough in
cooperation ~i~h the inner surface of
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the lower end of sald nozzle.
In an alternative embodiment, said feeder comprises
a vertical hollow outer cylinder having an opening for receiving
dough at the side wall thereof, a vertical hollow screw arranged
within said outer cylinder so as to rotate about its own axis
which is substantially aligned with the axis of said outer cyl-
inder thereby to feed downwards dough between the outer surface
of said screw and the inner surface of said outer cylinder, an
inner cylinder arranged to pass through said hollow screw and
providing a passage for allowing a food material other than dough
to pass therethrough, a nozzle having an annular lower end which
is arranged integrally with said inner cylinder at the bottom
thereof, said annular end defining an annular orifice for dis-
charging dough in cooperation with the inner surface of the
lower end of said outer cylinder, and a plug means arranged with-
in the lower end of said nozzle so that the peripheral surface
of the lower end of said plug means defines an annular orifice
for said food material other than dough in cooperation with the
inner surface of the lower end of said nozzle.
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~1~6~
The extrusion of dough material in a tubular form may
be conducted by a dough feeder comprising a vertical screw for
feeding dough, a passage in the axial portion of the screw for
feeding other material, and a double-layered annular outlet at
the bottom of the device, from which dough and the other material
flow down in the form of a tube wherein dough forms the outer
layer and the other material forms the inner layer.
The tubular material may be collapsed flat by its
own weight on a conveyor which advances substantially horizont-
ally. The flattened material may be stretched to a thin stripof a thickness such as 2 to 3 mm by a first stretcher comprising
a plurality of freely rotating rollers revolving along an
elliptical track having a straight bottom portion and a convey-
ing means positioned thereunder. The stretched strip of material
coming out of the stretcher may be suspended from the level of
the strip of material undergoing the stretching operation and
slowly swung back and forth guided by a swing
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~,, 'i. .
means such as a swinging plate so that it may be folded and piled up so as
partially to overlap itself in tens of layers on a continuously travelling
conveyor. The piled up multi-layered material may be stretched by a second
stretcher~ e.g. freely rotating rollers which are revolving along an ellipti-
cal track having a straight bottom portion and a conveying means positioned
thereunder without destroying the regularity of the layers in the material.
The above-mentioned conveying means in each of the first and the
second stretchers comprises a plurality of belt conveyors each of which has
individual feed speed, arranged in series in the order of feed speed such that
a downstream belt conveyor runs faster than an upstream belt conveyor. The
revolving speed of the rollers along the elliptical track is greater than
that of the fastest conveyor belt.
The conveyor means may have brush rollers interposed between any
pair of adjacent conveyor belts. The brush rollers3 due to the flection of
thin flexible bristles, can stably transfer dough material to any adjacent
downstream conveyor belt while all the flour on the upstream conveyor belt is
transferred simultaneously so that the dough material does not adhere to the
downstream conveyor belt.
Thus, the present invention affords a process which enables continu-
ous and automatic manufacture of dough material comprising dough in a multip-
- licity of orderly layers. The dough material may comprise layers of dough
and other material such as fat or oil overlapping alternatively. In the
apparatus for producing the dough sheets in a plurality of layers with or with-
out layers of fat or oil interposed in layers of dough~ the working distance
is substantially shorter than that necessary for any conventional automatic
apparatus of this kind. The process and apparatus of the invention are capable
of continuously producing dough sheets containing layers of oil or fat such
as butter without the problem of oil or fat being squeezed out or dough
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adhering to adjacent machille portions during stretching operations, with the
result that oil or fat may be orderly laminated.
Thus all of the difficulties encountere~ on the prior art have been
eliminated by the present invention.
In the present invention, a sheet of layered food nla.erial can be
continuously and automatically manufactured by extruding a desir~d number of
food materials in a tubular form, which comprises layers each of which are
substantially concentric in cross-section, and transferring the tubular food
material onto a continuously driven conveyor.
The extrusion of the food material in a tubular form having two
layers consisting of an outer layer formed of dough and an inner layer of
another material) is conducted by a feeder or extruder comprising a vertical
screw for feeding dough, a passage in the axial portion of the screw for feed-
ing other material, and a double-layered annular outlet at the bottom of the
feeder, wherefrom dough and the other material flow down in the form of a tube
wherein dough forms the outer layer and the other material forms the inner
layer. It will be readily understood that a tube having more than two layers
can be extruded by a slight modification of the above feeder or extruder by,
for instance, providing the feeder with additional screw or screws or addition-
al duct in the passage inside the screw, together with some attachments.
The tube may be collapsed flat by its own weight on a conveyor which
receives the tube. Then, the hollow portion of the tubular body disappears
and the innermost tubular layer merges into one body.
Accordingly, in one aspect the present invention consists in a
method of continuously manufacturing a sheet of layered food material, compris-
ing the steps of feeding out of a feeder or extruder continuously and simul-
- taneously a plurality of food materials in the form of a tube consisting of a
plurality of layers, and transferring the tube onto a continuollsly driven
-- 6 --
conveyor thereby to allow it to continuously collapse flat by
gravity on said conveyor to give the sheet of layered food material.
In accordance wit~ a second aspect the present invention
consists in an apparatus for continuously manufacturing a sheet of
layered food material, comprising a feeder or extruder for feeding
continuously and simultaneously two kinds of food material in the
form of a hollow tube consisting of two layers, and a continuously
driven conveyor means adapted to receive and convey the hollow tube
thereon, said feeder comprising a vertical hollow outer cylinder
having an opening for receiving dough at the side wall thereof, a
vertical hollow screw arranged within said outer cylinder so as to
rotate about its own axis which is substantially aligned with the
axis of said outer cylinder thereby to feed downwards dough between
the outer surface of said screw and the inner surface of said
outer cylinder, the hollow screw providing a passage for allowing
a food material other than dough to pass therethrough, a nozzle
having an annular lower end which is arranged integrally with sald
hollow screw at the bottom thereof, said end defining an annular
orifice for discharging dough in cooperation with the inner surface
of the lower end of said outer cylinder, and a plug means arranged
within the lower end of said nozzle so that the peripheral surface
of the lower end of said plug means defines an annular orifice for
said food material other than dough in cooperation with the inner
surface of the lower end of said nozzle.
Also, in the present invention, an inner cylinder may be
arranged to pass through said hollow screw without the cylinder
~eing forr.led integrally with the hollow screw as described above.
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~f
Said nozzle has an annular lower end which is arranged integrally
with said inner cylinder at the bottom end thereof in place of said
hollow screw as described above. Therefore, an annular orifice for
discharging dough is defined by said annular end of the nozzle in
cooperation with the inner surface of the lower end of said outer
~ - 7a _
cylinder. Purther, an annular orifice for said food material other than dough
is defined by the peripheral surface of the lower end of said plug means in
cooperation with the inner surface of the lower end of said nozzle.
For a better understanding of the invention, reference will now be
made by way of example to the accompanying drawings, in which:-
Figure 1 is a diagrammatic plan view of an embodiment of an apparatusaccording to the present invention,
Figure 2 is a diagrammatic side view, partially broken, of the
apparatus of Figure 1,
Figure 3 is a cross-sectional side view of a dough feeder to be
used in the above apparatus,
Figure 4 illustrates for reference purposes a cross-section of a
solid rod consisting of two concentric materials wherein the outer layer con-
sists of dough and the core portion consists of butter, extruded from a known
feeder or extruder,
Figure 5 is a cross-section of a sheet obtained by compressing the
solid rod shown in Figure 4, e.g. by flattening by gravity the tube shown in
Figure 16,
Figure 6 is a cross-section of a sheet obtained by flattening a
hollow tube having two concentric materials extruded from a dough feeder,
Figure 7 is a perspective view of a roller driving mechanism for
the first roller assembly of the apparatus,
Figure 8 is a diagram illustrating the operation of a portion of the
apparatus,
Figure 9 is a diagrammatic side view, partially in cross-section,
of the driving mechanism of a first stretcher and a swing means of the
apparatus,
Figure 10 is a plan view, partially in cross-section, of the driving
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mechanism shown in Figure 9,
Figure 11 is a diagrammatic side view, partially in cross-section,
of the driving mechanism of a second stretcher of the apparatus, and
Figure 12 is a plan view, partially in cross-section, of the same
driving mechanism as shown in Figure 11.
Figures 13 to 15 illustrate for reference purposes cross-
sections of several dough materials formed by the conventional methods, in
any of which core material is wrapped up with a dough sheet,
Figure 16 is a cross-section of a tube having two substantially
concentric layers extruded from a feeder or extruder used in the present
invention,
In Figure 3, dough (1) is supplied into a hopper (3) of the dough
feeder (F). Dough (1) consists, in case of pies, ordinarily of kneaded mix-
ture of wheat flour and water and sometimes contains about 15% of sugar.
In case of danish pastries, dough consists of kneaded mixture of wheat,
water, yeast fungi, salt and a small amount of butter.
The hopper (3) is f ixedly connected to the body portion of the
dough feeder (F), and contains therein a feed screw or screws (9) which are
disposed at the bottom of the interior chamber of the hopper (3). Dough in
d 20 the hopper is thus conveyed by the screw or screws (9) into the body portion
of the dough feeder (F).
The body portion of the dough feeder (F) comprises a vertical
- hollow cylinder (5) which forms an outer housing. Said cylinder (5) has a
cylindrical hollow portion, wherein a vertical hollow screw (19) is positioned.
The cylinder (5) and the screw (19) define an annular space therebetween. An
opening (7) is provided on the side wall of the cylinder (5) and the annular
space between the cylinder and the screw (19) is directly connected through
said opening (7) with the interior chamber of the hopper (3). Thus, dough (1)
in the hopper may be fed through the opening (7) into the anmllar space.
Oil or fat (1l), for example, butter for pies and Danish pastries
and lard for Chinese cakes, is supplied into a hopper (13) positioned above
the body portion of the dough feeder (F). The hopper (13) comprises in its
interior chamber pump means (17) for transporting oil or fat downwards and
into an inner cylinder (15) positioned below the hopper (13) and connected to
the circumference of an opening at the bottom thereof. The cylinder (lS) is
stationary and arranged within the hollow portion of the screw (19) concen-
trically therewith. The bottom portion of the cylinder (15) constitutes a
nozzle (16). A conical plug (25) is positioned concentrically with the inner
cylinder (15) at the bottom part thereof and is suspended from the inner wall
of the inner cylinder (15) through a support rod (27) so that an annular ori-
fice (29) may be defined between the plug (25) and the nozzle (16). The lower
end portion of the cylinder (5) forms a dough nozzle (31) which is concentric
with the annular orifice (29) so that an annular orifice (33) may be defined
betweeen the inner nozzle (16) and the dough nozzle (31) in the manner as illus-
trated in the drawing.
The lower end portion of the nozzle (31) and that of the inner
nozzle (16) may be constructed to be detachable from the remainder and may be
provided in variety of different sizes so as to be adapted to change the
dimensions of the orifices (29) and (33).
A sprocket wheel (21) is secured to the top portion of the hollow
- screw (19) for the rotation of the screw. The screw may be rotatably held by,
for instance, an extension of the hopper (13) ~hrough bearing means (23).
A feature of the use in the present invention of a conical plug
(25) is that when the diameter of the nozzle (31) is increased, the cross-
section of the discharged material may be kept unchanged by adjusting the size
of the conical plug (25). It even permits reduction of the ratio of the non-
-- 10 -- .
layered part consisting of dough alone at each end as against the layered
portion even when the diameter of the nozzle (31) is increased.
In Figure 2, the dough feeder (F) may be received by a support
(35) integral with the frame (37? of the apparatus. The power of a drive
motor (39) is transmitted through pulleys to reduction gears (41) of a ver-
tical output spindle type and reduction gears (43) of a horizontal output
spindle type simultaneously.
The output spindle (45) of the reduction gears (41) is operative-
ly connected to an input end of the screws (9) to drive them and to the
sprocket wheel (21) to rotate the vertical screw (19) so that dough (1) is
discharged from the annular orifice (33) contiinuously in a tubular form.
Further, since the pump means (17) extrudes fat or oil continu-
ously through the annular orifice (29) in a tubular form, it will be readily
understood that a dough material may be continuously extruded from the dough
feeder (F) in the form of a hollow rod or tube (47) consisting of an outer
layer of dough (1), an inner layer of oil or fat (11) and a central hollow
portion.
In this regard, it is to be noted that the dough material may be
extruded as a hollow rod or tube consisting of only one layer of dough, if
required, by feeding dough alone.
In another embodiment, the inner cylinder (15) may be omitted.
In this instance, the inner nozzle (16) may be provided at the lower portion
of the screw (19).
The advantages of the above hollow rod are expained below.
- When two strips of dough containing a layer of oil or fat in between where oil
or fat is exposed at both ends are subjected to stretching action, oil or fat
which is softer than dough iæ forced out of both ends by pressure and adheres
A
'.
. ''' ~ '" , ' '.
'; ' ' '' ' '' '~', ,'' '''~ ''' "
' ' '' ' ' ~
to the belt or other parts of tlle machine, so that a contimlous operation
sometimes becomes impossible. However, in the present invention no such danger
exists since dough envelops the inner material completely.
The advantages of the above hollow rod in comparison with a solid
continuous rod as illustrated in Figure 4 are that compression of dough mate-
rial is facilitated and that oil or fat (11) and dough (1), when pressed,
from more complete layers as shown in Figure 6 in comparison with the flatten-
ed solid rod as illustrated in Figure 5, wherein the non-layered parts at the
two ends are excessively large and the upper and lower dough portions are too
thin. In contrast, what is obtained from the hollow rod as shown in Figure 6
is superior in the formation of layers to that shown in Figure 5.
Since the ratio of the amount of dough as against oil or fat to
be folded into layers for Danish pastries is generally 1.4:1, when the solid
rod is flattened as shown in Figure 5, the part consisting of dough alone at
each end becomes excessively large, and no layer of oil or fat is formed there
while the ratio of oil or fat at the central portion remains excessively large
even if the material is folded in subsequent steps. This does not give any
product suitable for commercial use.
As described above, the dough nozzle (31) and the inner nozzle
(16) are each in the circular form. If they were in the flattened or rec-
tangular form, since the elevation angles of various portions of the inner
face of the nozzles are considerably different from each other because of the
required changes in the form of the vertical cylinder (5) and the inner cy-
linder (15) from the circle at their upper portions to flattened or elongated
shape at their lower portions, not only the discharge speed is different
between the middle portions and end portions, but also there occurs the
destruction of gluten tissue, which does not permit to produce good-quality
products.
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The dough materlal thus extruded is recelved by the first con-
veyor belt (65). The upper surface of the first conveyor belt (65) is strewn
with flour (67) by a flour feeder ~69) mounted on the frame (37) at a suitable
position upstream of the dough feeder (F). Consequently, the dough material
is extruded on the conveyor belt (65) strewn with flour.
The dough material is then carried for~ard on the conveyor belt
(65) to a position where it is pressed preliminarily by a press roller (71j
to a certain extent before it enters the first stretcher.
Above the press roller (71) is disposed a flour hopper (73).
Flour in the flour hopper is applied to the upper surface of the dough material
- through the press roller (71). Such a preliminary treatment is all conducted
on the first conveyor belt (65).
Subsequent to the above, the dough material is stretched to a
very thin strip and then undergoes folding and re-stretching operations to
form a multi-layered dough product. The number of layers obtainable in the
final product is to a large extent dependent upon the thickness of the dough
material stretched in the first stretching process.
The first stretching may be effected by the first stretcher com-
prising a number of rollers movable on the predetermined elliptical track by
means of chains, and a conveying means positioned thereunder comprising a
plurality of conveyor bclts. The first stretcher comprises the first roller
assembly (51) consisting of a number of small rollers (55) mounted through
bearings (57) on shafts (59) which in turn are rotatably, mounted on chains
(61) at equal intervals.
The chains (61) are trained around two sprocket wheels (63), so
that they form a flattened or elliptical track (a) on which the small rollers
(55) travel along with the rotation of the chains (61). The travel of the
outermost points of the small rollers (55) along the elliptlcal track (a)
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69
forms a ]ocus represented by (b) in Figure 8. The locus (b) has a straight
bottom portion facing the conveyor means, consisting of a plurality of convey-
or belts (65), (79) and (83).
The first conveyor belt (65) extends about 100 mm into the por-
tion adjacent the straight portion of the locus (b) and therebelow.
The dough material is fed into the gap between the lower straight
portion of the locus (b) and the upper surface of the upper flight of the
conveyor (65).
~ ownstream of the first conveyor belt (65) is arranged a second
conveyor belt (79) spaced about 50 mm apart from the first conveyor belt.
In the space between the first and the second conveyor belts, a brush roller
(81) is disposed. Due to the flection of the flexible bristles, the brush
roller (81) transfers dough material from the first conveyor belt (65) to
the second conveyor belt (79) while all the flour on the conveyor (65) is
transferred simultaneously so that dough does not adhere to the second con-
veyor belt (79). The length of the second conveyor belt (79) is preferably
50 to 100 mm. ~ third conveyor belt (83) is likewise arranged downstream of
the second conveyor belt spaced apart about 50 mm from the second conveyor
belt. Between the second conveyor belt (79) and the third conveyor belt (83)
is disposed at brush roller (85) as illustrated in Figure 8. The brush
roller (85) plays a similar role to that of the first brush roller (81).
The speeds of the first, second9 and third conveyor belts (65),
(79), and (83) are arranged such that a downstream conveyor moves faster
than any upstream conveyor. Similarly, the rotary speed of the second
brush roller (85) is higher than that of the first brush roller (81).
Since the length of dough material is extended by the stretching operation,
it is necessary to vary the speed of each of these conveyor belts and the
brush rollers so as to absorb the extension of the dough material.
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6~
The upper flight of the third conveyor belt (83) may extend
beyond the lower straight portion of the locus (b) after running therebelow
about 100 mm.
The space between the first, second and the third conveyor belts
and the lower straight portion of the locus (b) becomes continuously narrower
in the downstream direction.
It is to be noted that the number of the conveyor belts and the
- brush rollers is not critical. If the number increases and accordingly the
total length of the roller assembly, the capacity of the device may also
increase.
A higher stretching capability of the first stretcher enables
reduction of the height of the stack of the dough material folded and stack-
ed in the subsequent folding process. Consequently, a finished dough
product may contain more layers for a predetermined thickness.
In an experiment, dough material extruded in tubular form and of
20 mm thickness at the entrance of the stretcher could reduce its thickness
to 1.5 mm employing the stIetcher of the present invention com?rising three
- conveyor belts and two brush rollers in between. In the above experiment,
the effective operating length of the locus (b) was set at 330 mm, the
effective operating number of rollers (55) set at 5, and the revolving
speed of the rollers along the elliptical track (a) was set at twice the
travelling speed of the third conveyor belt (83).
In contrast, in a conventional stretching employing a pair of
cylindrical rollers rotating at a fixed position so as to cause dough
material to pass and to be pressed therebetween, the minimum thickness to
which dough material containing a large amount of sticky and soft material
such as butter can be stretched without breaking the infonnation of layers
is 5 mm. The limitation in the efficiency derives from the fact that
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pressure applied is concentrated on the surface between the rollers, so
that dough material tends to adhere to the rollers or be broken in the
stretching process.
The above stretching operation is followed by the process of
folding dough material. It is preferable that the stretched dough mate-
rial is fed through a pair of vertically arranged press rollers (151) and
(153) to a swing plate (155). The press rollers (151), (153) are rotated
at a certain speed in order to keep a constant supply of the dough mate-
rial for folding operation. They suppress whatever elasticity remaining
in the stretched dough material. The constant rotation of the rollers (151)
and (153) is effected by the engagement of gears (157), (159), (161), (163),
(165) and (167) (see Figure 9). The number of rotation of these rollers
(151) and (153) determines in coaction with their diameter the actual
amount (length) of dough discharged from them. This amount determines the
length (d) of the path of the swlng plate (155) at its lower end and the
speed (f) of the swinging motion of the swing plate (155).
In Figure 9, a crank pin (169) is mounted on the gear (161)
eccentrically to the shaft (171) thereof. To the crank pin (169) is con-
nected a crank rod (175), which in turn is connected to the shaft (173)
of the swing plate (155). The swing plate (155) is made to conduct
rotary oscillation through a crank rod (175) to determine the aforesaid
(d) and (f) in relation to the amount of rotation of the rollers (151) and
. (153). The input to the gear (161) will be explained later.
The roller (151) has a shaft (177) in its central portion. The
, shaft (177) is hollow and the rocking shaft (173) is inserted therein in
; such a manner that the movement of the rocking shaft (173) does not inter-
fere with that of the roller (151).
A cover plate (156) may preferably be attached to the swing
:.
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6~9
plate (155) by suitable means. The cover plate (lS6) rnay be substantially
parallel to the swing plate (155) and may have substantially the same length
with that of the swing plate. The cover plate can be removed from the swing
plate for cleaning.
The provision of the cover plate (156) permits the swing plate
(1~5) to be swung at a greater angle that the case the swing plate has no
cover plate, whereby the length of a layer of the folded dough material can
be increased.
The dough material fed from the swing plate (155) is folded on
the fourth conveyor belt (181) positioned below the swing plate (155) and ex-
plained later in further detail, into a continuous stack of a predetermined
height by the swinging motion of the swing plate.
If 2 mm thick dough material is piled up in 30 layers, the height
becomes 60 mm. If dough material piled up in as many as 30 layers to such a
thickness were subjected to compression by a single roller rotating around a
fixed shaft the diameter of the roller should be 1 m or more to conduct the
stretching operation without destroying the regularity of the pile, which size
is totally impracticable. This is because, at the portion of the roller where
it takes up material for compression, the surface of the roller has a tendency
- 20 to "repel" the material when the height of the material approaches the height
of the shaft of the roller.
Thus, the material in the upper part of the pile is repelled
from the surface of the single roller so that the regularity of the pile is
destroyed and is not taken up by the roller in a regular manner. Such a
result is contrary to the object of the present invention.
` In the above-described apparatus, loosely folded dough material
piled up in 30 Iayers and having a thickness of 60 mm can be taken up without
destroying the regularity of the layers by the roller assembly (53) of the
- 17 -
~6~
second stretcher. T}le roller assembly (53) comprises a number of rollers
revolving along an elliptical track ~a), the take-up end oE which has a
radius of curvature o only 85 mm.
The fourth conveyor belt (181) which supplies dough material to
the second roller assembly (53) moves in substantially the same direction as
the third conveyor belt (83) but differs in height.
This difference in height is the sum of the distance of the space
in which the swing plate (155) hanging from the dcwnstream end of the upper
flight of the third conveyor belt (83) can swing effectively and the thickness
of the dough material stacked thereunder to such a height as that at which the
stacked dough material may be stretched by the second stretcher. The fourth
conveyor belt (1~1) is mounted at a position which is compatible with such
difference in height.
The upper flight of the fourth conveyor belt (181) extends at its
upstream end into the portion below the second and third conveyor belts (79)
and ~83) so that it receives flour dropping from these conveyor belts. This
is effective in preventing dough from adhering to the belt.
The fourth conveyor belt (181) is disposed at an angle with the
lower straight portion of the locus (b) formed by the path of the outermost
portions of the small rollers (55). In the embodiment illustrated in Figure
8, the fourth conveyor belt (181) is provided at an angle (~)~ for instance,
about 20 relative to said straight portion of the locus (b), which is main-
tained horizontal. However, it is also allowable that the fourth conveyor
belt (181) is horizontal and the straight portion of the locus (b) is inclined
relative to the conveyor belt (181).
Thus, the plane portion of the outer envelope surface defined by the
r revolving rollers may be provided at an angle, for instance, about 20 relative
to the upper flight of the nearest upstream conveyor~ i.e. the upper flight
- 18 -
of the fourth conveyor belt (181). When said upper flight is positioned at
an angle of 20 to the above plane portion and the material is piled up on the
conveyor belt forming layers, each maintaining an angle of, for instance, 20
as against the plane of the upper flight of the conveyor belt ~181) 9 said
layers hold an angle of 40 relative to the level of the above plane portion.
Since the rollers revolve at a faster speed than any of said conveyors, the
cooperation of the rollers with the conveyors reduces the angle of the layers
towards zero.
The fourth conveyor belt ~181) approaches the lower straight portion
of the locus (b) of the second roller assembly ~53) at a certain angle ~) and
moves away from the straight portion of the locus (b) after it comes to a
position where it is separated from the locus (b) at a certain distance ~g).
At a certain interval (experimentally 50 mm), a fifth conveyor belt (183) is
arranged downstream of the fourth conveyor belt ~181). The distance (h) be-
: tween the fifth conveyor belt ~183) and the straight portion of the locus ~b)
is smaller than the distance (g). The speed of the fifth conveyor belt is
faster than that of the fourth conveyor belt ~181). Between the fourth con-
veyor belt (181) and the fifth conveyor belt ~183) is arranged a brush roller
(185). Downstream of the fifth conveyor belt ~183) is similarly arranged a
brush roller (187~, and downstream thereof is arranged a sixth conveyor belt
(189). The distance (i) between the sixth conveyor belt (189) and the locus
~b) is smaller than the distance ~h). The speed of the sixth conveyor
belt ~189) is faster than the speed of the fifth conveyor belt (183).
The upstream end of the upper flight of the sixthconveyor belt (189) may
extend about 100 mm below and along the straight portion of thelocus ~b)
and the remaining part thereof is outside said straight portion. The
leading end of the upper flight of the sixth conveyor belt functions to
- discharge the finished dough material.
In Figure 8, a friction plate (191) is disposed at the upstream end
- '.9 -
of the second roller assembl~ ~53) J along the locus (j) formed by the path
of tile innermost portions of the rollers (55) revolving along the elliptical
track ~a). The friction plate contacts the smaller rollers (55), which are
otherwise in free rotation, so as to forcibly rotate the small rollers in the
direction of the arrow (k) only where the friction plate is in contact with
them.
The force created on the surface of the rollers (55) when they
rotate in the direction of the arrow (k) acts to increase the action of the
rollers to take in the material. It pulls the material in the upper layers
of the piled up dough material in the direction of the movement of the con-
veyor belts and presses it so that it prevents the destruction of the regular-
ity of the layers in the piled up dollgh material. Thus, all the dough material
is led to the linear portion of the locus ~b) in a desired manner.
If the speed of progress (n) of the small rollers (55) along the
locu (a) is set at 70 times or more the travelling speed of the fourth con-
veyor belt, destruction of the order of the layers in the piled up dough
material can be prevented without the use of the friction plate (191). How-
ever, if the speed of progress ~n) cannot be set at such a high speed, the
friction plate is required.
When both of the above expedients, namely, the increase of the
speed of progress (n) and the friction plate (191), are used in combination,
dough material piled up at a greater height can be rolled without trouble.
In an experiment, with the radius of curvature of the locus (b)
set at 85 mm, the length of the major axis of the elliptical orbit set at 520
mm, the number of the operating rollers ~55) set at 8, and the speed of pro-
gress of the rollers along the locus ~a) set at 15 times the speed of the
sixth conveyor belt ~189), dough material containing butter layers piled up in
30 layers (counting the dough material before folding as one layer) and having
a height of 60 mm was stretched to a thickness of 3.5 mm, wherein thin layers
- 20 -
of butter were arranged without any disorder.
Turning to the driving mechanism, the rotation of the motor ~39),
as illustrated in Figure 2, is transmitted to reduction gears (41) and (43)
simultaneously, and the output spindle ~45) of the reduction gears (41) is
operatively connected to the dough feeder (F). In Figures 9 and 10, the output
spindle (201) of the reduction gears (43) is operatively connected to a bi-
directional output bevel gear box (203), the output of which is conveyed
through spindles (205) and (207) (Figure 9).
The spindle (205) rises vertically to rotate a gear (209~ which
in turn rotates a shaft (211) through a gear (213) (Figure 10). The shaft
(211) rotates the drive shaft (215) of the first roller assembly (51) through
bevel gears ~Figure 7). In Figure 9, bevel gear (217) fixed on the middle of
the shaft (205) transmits power to the rollers (151) and (153) by rotating
the gears (157), (159), (161), (163), (165) and (167), and simultaneously the
;~ swing plate (155) through the crank pin (169), crank rod (175) and the shaft
(173) of the swing plate.
The gear (157) also engages with a gear (219) to rotate the input
rollers (221) and (223) of the third conveyor belt (83). The rotation of the
gear (219) is transmitted through a chain to a gear (225) which engages with a
gear (227) to rotate the input rollers (229) and (231~ of the second conveyor
belt (79). The gear (225) engages also with a gea.r (233) which transmits the
rotation through a timing belt to the shaft ~235) of the brush roller (85).
A power transmission system divided out from the gear (227) per-
forms the drive of the input rollers (75) and (77) of the first conveyor belt
(65), the drive of the shaft (237) of the brush roller (81), and transmits the
input to the press roller (71).
The spindle (207) extending from the bevel gear box (203) enters
a gear box (239) which has two output shafts ~241) and ~243) (Figures 11 and
- 21 -
12). The output shaft ~241) rises vertically to drive the second roller assem-
bly ~53), and the other output shaft ~243) extends laterally to rotate the
input rollers ~245)~ ~247), ~249) of the fourth, fifth, and sixth conveyor
belts, respectively~ and the brush rollers ~185) and (187).
A roller ~251) and gears (253) may be provided for transmitting
power to a further conveyor not shown.
In any of Figures 13 to 15, a core material ~A) is merely wrapped
up with dough sheet (B) according to the conventional method. In Figure 13,
the dough (B) is thick at the position _. Dough at the position a is thinner
than at the position b. The reason is that the position _ is where the ends of
the dough strip are overlapped. If dough ends are made to come in contact as
in Figure 15, without any any overlapping portion, the oil product would be
exposed and the subsequent stretching operation would become impossible. There-
fore, the dough ends must be overlapped sufficiently as in Figure 13.
Figure 14 shows an example wherein the overlapping portion comes on
one side of the body. The thickness of the dough at the overlapping portion,
- taken at the position b' as well as taken at the position a, is substantially
larger than those of position _.
The above unevenness in the thickness of the wrapped-up material
will remain through the subsequent stretching and folding operations and in
the multi-layered end product. This results in a defect in the quality of
the end product. Namely, the uneven thickness prevents the dough product
from rising evenly at the baking stage, or heat would not conduct evenly
through the dough product.
As indicated above, Figure 4 shows a cross-section of a product hav-
ing a form of solid rod consisting of two substantially concentric materials
extruded from a known feeder or extruder. The application of pressure on two
opposite sides of the tubular body shown in Figure 4 will give a flat body as
- 22 -
showll in Figure 5, wherein the dough (B) is unduly thicker at the position c
than at the position _. This does not eliminate the defect in the conven-
tional methods as shown in Figures 13 to 15.
Figures 6 and 16 explain the present invention. Figure 6 shows a
cross-section of a cylindrical body (4) extruded continuously from a feeder
or extruder (Figure 3) of the present invention. On the interior surface
of the cylindrically formed dough (B) is found a core material such an oil
product (A). The center of the cylindrical body consists of a hollow portion
(3).
If dough and the oil product are supplied in the above positional
relationship, the cylindrical body becomes flat as shown in Figure 6 by a
light pressure on opposite sides thereof. The thickness of the dough (B) is
even at either of positions e and f, thus resolving the difficulty in the
conventional methods.
l~len the present invention (Figure 16) and the above comparative
example (Figure 4) are compared as to the processibility in the subsequent
steps, it will be clear that the force required for extension is far smaller
in the present invention than the comyarative example.
The present invention employs a method wherein a hollow cylinder
is first produced and then it is flattened. This method has the following
advantage as compared with a method wherein dough outlet in the extruder is
virtually rectangular or oval or takes any other flat configurations. Name-
ly, when dough (or the oil product) is extruded from the nozzle of the extruder
the friction between the dough and the walls of the nozzle affects the velo-
city of extrusion. In case the nozzle outlet is rectangular or oval, *he
velocity of extrusion at the two ends in the direction of a longer dimension
becomes slower than the portion in the direction of a shorter dimension and,
in detail, no even extrusion velocity can be obtainecl throughout the cross
- 23 -
~1~6~
section of the nozzle outlet. If, however, the cross section of the nozzle
is of substantially circular ring as in the present invention, the extrusion
velocity becomes even throughout the cross section. If there is any unevenness
in the extrusion velocity of dough (B), it affects the end product in the
form of uneven thickness of dough layers. The above equally applies to the
extrusion of the oil product (A).
The device to be used for the method of the present invention will
now be explained.
In Figure 3, (3) represents a hopper for introducing dough (1).
(9) represents a screw which transports the dough (1~ into a vertical cylinder
(5) through a side portion thereof. (19) represents a vertical screw for
guiding the dough (1) introduced into the vertical cylinder (5) to the ex-
trusion outlet at the bottom of the vertical cylinder (5). The vertical screw
(19) is made to rotate by sprocket (21) and is supported by a pair of
bearing assemblies (23), (23) vertically aligned.
(16) represent a hollow cylindrical nozzle inserted concentrically
into the hollow portion formed along the axis of the vertical screw (19).
The nozzle (16) constitutes a passage for the oil product (11) and is stationary
while the vertical screw (19) rotates. At a lower portion of the nozzle (16),
a conical plug (25) is suspended by a support rod (27) so that an annular gap
may be defined between the plug (25) and the nozzle (16).
(17) represents pump means for transporting oil or fat downwards
and into the nozzle (16). (13) represents a hopper for oil or fat (1).
(31) represents a dough nozzle formed at the bottom end of the vertical
cylinder (5). The dough nozzle (31) is positioned concentrically with the
conical plug (25) and the nozzle (16) and is mounted onto the vertical cylinder
(5) from a lateral side thereof. The lower end of the nozzle (16~ and the
lower end of the dough nozzle (31) are positioned concentrically,
~, - 24 -
and form an annular gap therebetween for extruding dough. Again, between the
lower-end periphery of the conical plug (25) and the lower end of the nozzle
(16) is formed a similarly annular gap for extruding the oil product. These
gaps function to form the extruded dough and the oil product into a two-layered
and hollow cylindrical body.
The dough fed into the vertical cylinder ~5) is moved downwardly by
the action of the vertical screw (l9) and is discharged from the dough nozzle
(31). Since the conical plug (25) is positioned at the center of the dough
nozzle (31), the dough is discharged from the annular gap in the form of a
cylinder. When the dough is discharged, the oil product flowing down the
surface of the conical plug (25) comes into contact with the interior surface
of the cylindrical dough (1). Thereby, a cylindrical body (47) made of the oil
: product and the dough put together in two layers is manufactured continuously.
The hollow cylindrical body (47), while being continuously manufactured,
is received and conveyed sideways by a conveyor (65). While the cylindrical
body is received and conveyed, it collapses by its own weight to form a flat
sheet. In this case, the oil product of the inner cylindrical layer is
united into one body. The thus flattened sheet may then be further subjected
to the flattening action of a roller (71) so as to reduce its thickness. The
sheet thus formed may undergo further flattening or stretching operations
and is folded to give an end product, i.e. a multi-layered dough product.
Although preferred embodiments of the present invention have been
illustrated and described, it will be apparent to those skilled in the art
that various changes and alterations may be made therein without departing
from the spirit of the invention and the scope of the appended claims.
