[0001] This invention relates to a packaging system and method of packaging. Steam aseptic
packaging systems and methods have been used commercially for many years. The substitution
of other heated gases (including air) for steam is noted in literature (e.g. Martin
Patents No. 2,549,216 and No. 2,631,768). The use of hot air as contrasted with steam
offers a number of important advantages.
[0002] One of the most important advantages is the saving in energy required to vaporize
water to create steam, with a consequent saving in fuel expenses. It has been found
that at somewhat increased volumes the lethality of hot air is comparable to that
of superheated steam. within the sterilizing sections of the system, the heated air
is recirculated providing for increased energy conservation and savings.
[0003] A second important advantage of the use of hot air is a lessening of deterioration
of parts which have heretofore been attacked by the steam and also a lessening of
the saturation of the insulation of the casings occasioned by condensation of water
in such insulation, lessening its thermal efficiency.
[0004] Still another advantage of the use of hot air is the fact that when steam is used
in the headspace of a container, because of condensation, there is a tendency to collapse
the walls of the container. Using hot air eliminates this tendency and therefore permits
the use of thinner walls of metal and glass containers and also makes the use of fiber
and plastic containers practical, along with other containers constructed with less
rigid material.
[0005] The invention provides a hot air aseptic packaging system comprising a container
sterilizer, said container sterilizer comprising a first casing, a first conveyor
within said first casing, means for feeding empty containers. into said first conveyor,
means for discharging containers from said first conveyor, first heating means, said
first heating means comprising a heater for raising the temperature of air to a sterilizing
temperature and blowing means for blowing sterile air above atmospheric pressure throughout
said first casing to sterilize said containers as they pass through said first conveyor;
a second conveyor section comprising a second casing, a second conveyor in said second
conveyor section receiving containers from said first conveyor, a filler in said second
casing positioned to fill product into said containers as they travel on said second
conveyor, means for delivering sterile product into said filler, first transfer means
for discharging sterile filled containers from said second conveyor, means for.maintaining
sterile air at above atmospheric pressure within said second casing; a lid sterilizer
comprising a magazine for lids, a third conveyor receiving lids from said magazine,
second heating means for heating air to sterilizing temperature, means for circulating
sterile air at above atmospheric pressure around said lids as they travel along said
third conveyor to sterilize said lids, second transfer means for discharging sterile
lids from said third conveyor, and an enclosed closer comprising means to receive
containers from said first transfer means, means to receive lids from said second
transfer means and position one lid on top of each container, means for attaching
each lid to its respective container, and means for discharging closed containers
from said closer, and means for maintaining pressure in the said closer above atmospheric.
[0006] The first conveyor preferably comprises a belt, a drum and means for guiding and
driving the belt in a continuous helical path around the exterior of the drum. The
first heating means may further comprise a return duct drawing air from the first
casing back to the blowing means in a recirculation path. The heater may typically
be of the electric resistance type.
[0007] The second conveyor preferably comprises a helical conveyor having a first section
of a first pitch and a second section of a second pitch greater than the first pitch,
the system accommodating containers having top outward flaring flanges, the first
pitch being less than the outside diameter of the flanges to force the flanges of
adjacent containers into close proximity, the filler being disposed above and extending
longitudinally of said helical conveyor above said first section; the filler having
a' longitudinally extending slit through which product is continuously discharged
in a ribbon into said containers.
[0008] The second conveyor section may further comprise a duct, means for delivering sterile
air into the duct, and means for delivering sterile air from the duct into the second
casing at above atmospheric pressure. The means for delivering sterile air can be
independent of the first . heating means. Cooling means may optionally be provided
in the second casing to reduce the temperature of the containers; this cooling means
may comprise a pipe and means for circulating sterile cool fluid through the pipe,
the pipe having a spray aperture to spray fluid onto the exteriors of the containers.
[0009] The means for maintaining sterile air preferably further comprises cooling means
for cooling the sterile air.
[0010] The means for delivering sterile product may comprise means for creating above atmospheric
pressure in the product and a valve between the last-named means and the filler, the
valve having a discharge port, a seat inward of the discharge port, a head shaped
to engage the seat, resilient means biasing the head into engagement with the seat,
the head being movable out of engagement with the seat when the pressure in the valve
overcomes the force of the resilient means, whereby excess product is discharged from
the valve through the discharge port.
[0011] The lid sterilizer may comprise a heat insulated third casing around the third conveyor
and the second transfer means, the third casing being separated by a partition into
. upper and lower parts, the third conveyor having at least one continuous member-and
means for driving the member, the member moving the lids in the upper part and returning
through-the lower part, the means of circulating sterile air delivering the air at
sterilizing temperature into the upper part adjacent the magazine, a duct from the
lower part back to the second heating means for recirculation back to the upper part.
The third conveyor preferably.comprises two horizontally spaced apart members driven
together, the lids being tangential to both the members as the members are driven
along the upper part.
[0012] The closer may be enclosed by a third casing and may further comprise a duct for
sterile heated air above atmospheric pressure leading into the third casing, the duct
discharging into an air distributor located adjacent the means for discharging closed
containers, the air distributor having apertures opening into the third casing. The
discharging duct preferably also discharges into the means for maintaining sterile
air in the second conveyor section, while the second conveyor section may typically
communicate with the third casing.
[0013] The invention also provides a method of hot air aseptic packaging comprising: sterilizing
empty containers by conveying said containers in an enclosed first area while subjecting
said continers to hot air at a temperature in the range of 300-400°F (approx 149-2040C)
for a period of time in the range of 60 to 240 seconds, conveying sterile containers
through an enclosed second area in sterile air above atmospheric pressure, providing
sterile product into said second area, filling said product into said containers,
sterilizing lids for containers by conveying said lids in an enclosed third area while
subjecting said lids to hot air above atmospheric pressure at a temperature at about
400°F (approx 204°C) for a sufficient period of time to sterilize said lids, delivering
sterile filled container and sterile lids into an enclosed fourth area, applying said
lids onto said containers and securing said lids to said containers.
[0014] The conveying sterile container step preferably includes forcing the containers close
together in a line and then providing the product in a ribbon above the line to flow
into the containers substantially without spillage. The containers may advantageously
have outward turned flanges, the flanges overlapping as the product is filled thereinto.
[0015] The containers are preferably cooled to a range of about 75-90°
F (approx 24-32
oC) before filling, the product also being cooled for filling. By sterilizing and then
cooling containers and by sterilizing and then cooling the air which exist at greater
than atmospheric pressure in the filler area, pre-sterilized and cooled product may
be filled into the containers at a much lower temperature than is possible where steam
is employed, thereby avoiding the deterioration at elevated temperatures which otherwise
occurs. Furthermore, containers made of products such as fiber are less likely to
be damaged under the conditions heretofore set forth. This reduces degradation of
the product.
[0016] The sterilizing lids step preferably comprises providing a stack of lids, turning
the stack of lids horizontal, and conveying the lids horizontal touching each other
while heating the lids for sufficient time to sterilize the lids. The stack of lids
may be turned around corners so that the lids fan apart while turning the corners,
the hot air having access to the tops and bottoms of the lids while fanned apart.
I
[0017] The steps-of applying and securing the lids is preferably performed in an enclosed
area to allow sterile air to be blown into the enclosed area. The sterile air for
the step of conveying sterile containers may be typically from the same source as
the air provided in the step of applying and securing lids.
[0018] The invention further provides a filler for use with a hot air aseptic packaging
system comprising, a tunnel, a straight-line conveyor in said tunnel receiving sterile,
empty containers at a first end and discharging said containers filled with sterile
product at a second end, a filler in said tunnel positioned above said conveyor, first
means for delivering said sterile product to said filler, second means for delivering
sterile air under pressure to said tunnel, support means supporting said filler from
said tunnel, said filler comprising a casing extending longitudinally above the path
of said containers as they are moved along said conveyor, said casing being formed
at its bottom with an elongated longitudinal first slit, a tube of lesser diameter
then the interior of said casing disposed within said casing perforated at its top
and connected to said first means, an elongated insert formed with a second slit disposed
in said first slit, and detachable means securing said insert to said casing, whereby
said insert may be replaced with another insert having a second slit of different
width, product received by said tube flowing into the space between said tube and
said casing, thence out through said second slit and into said containers.
[0019] Advantageously, the slit through which product is discharged is interchangeable,
the width of the slit determining the volume of product dispensed. Merely by substituting
parts having slits of different width, this adaptability of the filler to different
rates of product flow is achieved.
[0020] An optional feature of the filler is its adjustability for different heights and
widths of containers. A filler tube in which the slit may be installed is preferably
supported in the filler chamber in such manner that it may readily be raised and lowered
to accommodate different container heights. Additionally, guides which maintain straight
line travel of the containers may be moved apart or together to accommodate different
container widths.
[0021] The conveyor preferably comprises a helical conveyor having a first section of a
first pitch and a second secticn of a second; pitch greater than the first pitch,
the system accommodating containers having top outward flaring flanges, the first
pitch being less than the outside diameter of the flanges to force the flanges of
adjacent containers into close proximity.
[0022] Cooling means may advantageously provided in the tunnel to reduce the temperature
of the containers; this means preferably comprises a pipe and means for circulating
sterile cool fluid through the pipe, the pipe having a spray aperture to spray fluid
onto the sides or exteriors of the containers, optionally before filling. At least
one of the guides may consist of a tube having spray holes through which sterile,
cooled water may be sprayed on the containers as they pass therealong.
[0023] The means for maintaining sterile air preferably further comprises cooling means
for cooling the sterile air.
[0024] The support means may comprise vertical members on either side of the tunnel, brackets
fixed to said casing and extending outward to either side of the tunnel, and clamp
means to clamp the outer ends of the brackets to the vertical members, the clamp means
being detachable, whereby the filler may be raised or lowered relative to the conveyor
to accommodate containers of different heights.
[0025] The first means may comprise means for creating above atmospheric pressure in the
product and a valve between the last-named means and the filler, the valve having
a . discharge port, a seat inward of the discharge port, a head shaped to engage the
seat, resilient means biasing the head into engagement with the seat when the pressure
in the valve overcomes the force of the resilient means, whereby excess product is
discharged 'from the valve through the discharge port. A second valve may be provided
between the first mentioned valve and the filler, the second valve having a second
seat, a second head, and an external actuator for closing the second head against
the second seat and for moving the second head away from the second seat variable
distances.
[0026] The invention still further provides a filler valve comprising a body having a first
inlet port and a first outlet port and a third port, a first seat in said body between
said first inlet and said first outlet ports, a first head shaped to seal against
said first seat, a first stem fixed to said first head and extending out through said
third port, resilient means biasing said first head against said first seat, said
resilient means being adjustable in force, means for delivering product under pressure
from a source to said first inlet port, means for returning product from said first
outlet port to said source; a second body having a second inlet port connected to
said first outlet port, a second outlet port adapted to be connected to a filler,
and a fourth port; a second seat in said second body between said second inlet port
and said second outlet port, a second head shaped to seal against said second seat,
a second stem fixed to said second head and extending out through said fourth port
and actuator means connected to said second stem to move said second head against
said second seat and to move said second head away from said second seat variable
distances.
[0027] The valve can be installed between the pump or gravity feed of the product and the
filler to prevent overflow of product, which might otherwise clog the filler and require
the line to be shut down until the overflow is cleaned and also to maintain the product
being forced into the filler at a uniform pressure.
[0028] An advantage of the present invention is the reduction in the required floor space
of the packaging facility.
[0029] A further advantage of the invention is an additional reduction of energy requirements
by recirculation of air in the container and lid sterilizing and other portions of
the system.
[0030] Still another advantage of the invention is that the use of pressurized air prevents
introduction of non-sterile air from the atmosphere into the system after the container
and lids have been sterilized.
[0031] An additional advantage of the invention is that many of the components of the system
comprise adaptations of. standard pieces of equipment, thereby making unnecessary
large scale redesign of these components and large inventories of spare parts.
[0032] Windows may be provided in the various components to allow continuous visual inspection
of the product, containers and lids.
[0033] An embodiment of the invention will now be described, by way of example, referring
to the accompanying drawings, in which:
Fig. 1 is a schematic perspective view of the system in accordance'with the present
invention;
Fig. 2 is a top plan view of the container sterilizer portion of the invention;
Fig. 3 is a side elevational view of the structure of Fig. 2 partly broken away in
section to reveal internal construction;
Figs. 4A and 4B are a composite top plan view of the container tunnel and filler portion
of the apparatus;
Figs. 5A and 5U are a composite side elevational view of the structure of Figs. 4A,
4B;
Fig. 6 is a transverse sectional view taken substantially along the line 6--6 of Fig.
4A;
Fig. 7 is a fragmentary sectional view taken substantially along the line 7--7 of
Fig. 6;
Fig. 8 is a perspective view of the container lid feed and sterilizer;
Fig. 9 is an enlarged sectional view through a portion of Fig. 8;
Fig. 9A is a schematic plan view of Fig. 9;
Fig. 10 is a transverse sectional view taken. substantially along the line 10--10
of Fig. 9;
Fig. 11 is a schematic top plan view of a portion of a container closing machine with
parts omitted for clarity and also showing a portion of the filler and tunnel;
Fig. 12 is a sectional view taken substantially along the line 12--12 of Fig. 11;
Fig. 13 is an enlarged elevational view, partly broken away, in section, of a valve
which may be used in the system;
Fig. 14 is a sectional view similar to Fig. 6 of a modification;
Fig. 15 is an enlarged sectional view of a portion of Fig. 14;
Fig. 16 is a view similar to Fig. 1B of a modified valve.
[0034] Directing attention to Fig. 1, the essential components of the system are set forth.
Containers 19 having top flanges 20 and which may be metal, fiber, glass,plastic or
other material are fed into a container sterilizer 21 where they are heated to a temperature
of up to approximately 500°F by hot air. The containers then pass through a straight-line
conveyor 22 which includes a filler section 23 where a pre-sterilized, cooled liquid
or semi-liquid product is filled into the containers. From the conveyor 22 the containers
pass into a closing machine 24 which is a modified, enclosed adaptation of a well-known
commercially available machine. Meanwhile the lids 18 for the containers, deposited
in a lid storage magazine 26 pass through a lid sterilizer 27 and thence up an inclined
lid conveyor 28 to;the closer 24. In the closer 24 the lids are attached to the container.
The components of the system will be described in detail.
CONTAINER STERILIZER
[0035] The container sterilizer 21 shown in some detail in Figs. 2 and 3 has a double walled
casing 31 filled with a heat insulation material 32. In the walls of the casing 31
at convenient intervals are observation windows 33. The containers 19 are fed into
sterilizer 21 through the container inlet 34 preferably in double file. From the bottom
of the inlet 34 the containers, still in double file, pass onto a conveyor belt 36
which passos around and over the power driven intake pulley 37. The conveyor belt
36 passes in a helical upward path around a central primary drum 38. A helical trackway
39 supports the belt 36 in its path. The containers pass down through a discharge
chute 41 and out of the casing 31. The belt 36 is directed by end pulley 42 and additional
pulleys 43 back to the intake pulley 37. The structure herein illustrated is a modification
of a commercially available conveying system such as that shown in Patent No. 3, 348,659.
[0036] Mounted at a convenient location such as the top of the' sterilizer 21 is a heater
46 which may bo electric, gas or oil fired. In a preferred device a resistance electric
heater is used. A blower 47 forces controlled air up from the air return duct 48 through
duct 51 which contains the heater 46 and then down through inlet duct 49 which leads
into the casing 31. The air is preferably at a suitable temperature such as 300°F
(approx 149°C) for fiber containers which is sufficient to sterilizo containers when
they are subjected to such a temperature for a period of about 60 to 240 soconds,
normal time for containers 19 to pass through the sterilizer 21. For metal and glass
containers 450°F (approx 232°C) is suitable. The resident time in the container sterilizer
may be varied by increasing or decreasing the speed of the conveying system.
CONTAINER TUNNEL AND FILLER
[0037] Communicating with the lower end of the discharge chute 41 is a horizontally disposed
tunnel 61. Continuously moving within the tunnel 61 is a conveyor chain 62 and onto
the horizontal top stretch of the chain 62 the containers pass in single file. Pulley
63 designates the driver pulley at the proximal end of the tunnel 61.
[0038] About midway of the tunnel 61 is an idler pulley 66 around which the chain 62 passes
and returns to pulley 63.
[0039] Containers 19 are restrained as they are discharged from chain 62 and received in
helix 71 by guide 68. Guide 68 carries horizontal rods 226 which slide in holes in
U-shaped brackets 227 and are biased inwardly by springs 228. Brackets 227 are adjustably
held by bolts 229 threaded into the wall of tunnel 61. The heads of bolts 229 are
externally accessible for adjustment.
[0040] Mounted horizontally within dhe distal path of the tunnel 61 is helix 71. Helix 71
has at its proximal end flights 72 which are uniformly spaced apart slightly less
than the diameter of the flanges 20 of the containers 19 being handled. It will be
understood that for different size containers 19 different helices 71 are required.
At the distal end of the helix 71 the flights 73 are spread apart, for a purpose which
hereinafter appears. Shaft 74 of helix 71 is mounted in bearings 75 at either end.
The containers 19 discharged off chain 62 are supported partially by horizontal plate
76 and partially by the vertical flange 78 of horizontal bar 77. There are holddown
bars 79 mounted horizontally to engage the top flanges of 20 of the containers 19.
Bars 79 are supported by brackets 81. As best shown in Fig. 6 the bars 79 may be moved
in and out to accommodate containers of different sizes. The containers 19 are partially
supported and are.driven by the flights 72, also as best shown in Fig. 6. The containers
are kept in contact with the helix 71 by means of horizontally disposed vertically
spaced apart tubes 82. Tubes 82 preferably perform an additional function in that
sterile cooling water may be pumped therethrough and the tubes are formed with spray
holes (not shown) which spray water against the sides of the containers 19, cooling
and cleaning the same. The spray water drains from the tunnel 61 through drain 83.
[0041] Helix 71 is driven from a power take-off 86 of the closer 24. Thus the take-off sprocket
86 drives chain 87 which is connected to sprocket 88'on the shaft 74 of helix 71.
Idler sprocket 89 maintains the chain 87 tight. Shielding 91 functions as a guide
for containers 19 at one side.
[0042] There are windows 92 along the length of the tunnel 61 through which the attendant
can observe the containers 19 as they pass under the filler which is to be described.
A cover 93 is hinged by hinge 94 so that in case of malfunction the operator may obtain
access to the interior of the tunnel 61. Within the tunnel 61 is a distributor 96
having air holes 96A which distributes air throughout the interior of the tunnel.
There is a duct 97 alongside the tunnel 61 communicating at intervals with distributors
96. It will be understood that the tunnel 61 is preferably of double-walled construction
and the space between the walls is filled with insulation 98 which may be a ceramic
fiber. The materials of which the walls are constructed are preferably stainless steel
both inside and out.
[0043] To sterilize the air within the tunnel 61 and also, importantly, to prevent the ingress
of non-sterile atmospheric air, blower 101 is installed in a convenient location such
as the top of the sterilizer 21 adjacent the blower 47. Blower 101 communicates with
a heater 102 which heats the air to a temperature of about 400°F (approx 205°C), thence
to a horizontal duct 103 along the top of the sterilizer 21 and thence down through
a vertical duct 104 to a horizontal duct 106 which communicates with the duct 97.
At start-up, air is preferably at 450-500°F (approx 232-260°C) and then reduced.
[0044] Where it is desirable, a heat exchanger 107 may be installed in the vertical duct
104. The heat exchanger 107 has a coolant inlet 108 and a coolant outlet 109. Within
the heat exchanger 107 are coils (not shown, but of a common commercial type) around
which the hot air in the duct 104 circulates and by which ita comporature 1a materially
reduced. Some products deteriorate rapidly at high temperatures. Accordingly, it is
desirable to cool the air emitted through duct 106, while maintaining its.pressure
above ntmospheric. Such sterile air, cooled but above atmospheric pressure, is introduced
in the filler 111. The pressure of the air prevents ingress of non-sterile air from
the surrounding atmosphere. Since both the containers and tho product have been pre-sterilized,
contamination of the product in the containers is avoided. Low temperatures if necessary,
as low as 70°F (approx 21°C) - may be used, a condition which is never achievable
with the use of ateam as contrasted with air.
[0045] Filler 111 is a modification of a commercially known structure. It is mounted above
the path of the containers 19 by means of horizontally outwardly extending brackets
251 spaced at intervals along the length of the filler 111. Each bracket 251 is received
in a clamp 252 which i.a, in turn, supported from a vertical support 253 on the side
of the filler by moans of bolts 254. By raising and lowering the clamp 252 - i.e.,
by inserting the bolts 254 through different holes in the support 253, the filler
casing 116 may be raised and lowered.
[0046] The containers 19 are supported against lateral displacement by guides 256 fixed
to brackets 257. Threaded rods 258 are threaded into the vertical flanges of brackets
257. These rods 258 pass through one of several vertically spaced holes in vertical
support 259 and are fixed in place by means of nuts 261. Accordingly, by turning threaded
rods 258, the brackets 257 and hence the guides 256 may be moved inward and outward
so that the guides engage the walls of the containers 19 as they pass under the filler.
By raising or lowering rods 258 and inserting same through different holes in support
259, guides may bo positioned near the tops of containers 19. The lower edges of tho
containers 19 are guided by bottom guides 262.
[0047] Filler 111 has a horizontally disposed casing 116 formed with a continuous slit 117
along its bottom edgo. Interchangeable inserts 266 of Teflon or other suitable material
are attached to the slit 117 by means of brackets 267 held by bolts 268 into casing.
The width of the slite 269 in tho inoort determines the rate of flow of product. By
replacing the insert 266 different product flow may be obtained.
[0048] A curtain of product is discharged through the slit 269 in the insert 266 immediately
above the path of the contain- ors 19 as they are moved along by the helix 71. Pre-sterilized,
cooled product is pumped or otherwise forced into a tube 118 within the casing 116.
Tube 118 has holes 119 at intervals at its top so that the liquid or semi-liquid product
is forced out through the holes 119 and into the interior of the casing 116. The product
is fed through an inlet 112 at one end of tube 118. This structure of filler 111 has
been found to promote more even distribution of product. The pitch of the flights
72 below the filler 111 is such that the containers 19 arc forced together so that
the flanges 20 partially overlap. Hence, there is a minimum of spillage of product
discharged through slit 269.
[0049] Directing attention to Fig. 13, a valve 191 which may be used to by-pass flow of
product into filler 111, particularly where multiple fillers are used in a particular
installation, is shown. Pre-sterilized, cooled product is pumped by pump (not shown)
in the product processing plant which is separated from the installation shown in
Fig. 1 in many instances by a partition 192. A pipe 194 connects with the pipe 193
extending through the partition, the pipe 194 having a flange 196, which is fasten-
od to the partition 192. Pipe 194 may bo connected to an elbow 197. Used throughout
the installation are quick-connect couplings 199 of conventional construction. Elbow
197 is connected to an intake 198 of the valve 191. Discharge port 201 of valve 191
is connected to a too 202. The opposite end of tee 202 may be connected to a pipe
203 which lends to another filler. However, it may be considered that the discharge
or vertical leg 204 of the tee 202 is connected by moans of pipe 206 to the inlet
122 ; of the filler 111. Other means of connection may, of course, be employed.
[0050] Within the body 198 of valve 191 is sleeve 211 having a reduced diameter portion
212 and an enlarged diameter portion 213. The juncture of the portions 212 and 213
are formed with a. seat 214, preferably conical. Valve head 216 is' formed at one
end with a taper 217 which matches the seat 214. Head 216 is connected to stom 218
which is biased by means of spring 219 into senting ongagement. A fitting 221 is connoctod
to tho sleeve 211 and such fitting 221 has a discharge port 222 which leads back to
the source of product. Temperature sensor 224 is connected to the body 201 to sense
the temperature of product discharged therefrom.
[0051] In the use of the valve, the product is pumped by means not shown through the pipe
193. Normally, the head 216 is seated and product flows out through reduced diameter
portion 212 to the right as viewed in Fig. 13 and thence through tee 202 and pipe
206 to the filler 111. In the event that the line is shut down or if the volume of
product being pumped through the pipe 193 is excessive, the pressure within the reduced
diameter portion 212 increases to the point where it overcomes the force of the spring
219 and the head 216 moves to the left as viewed in Fig. 13. Surplus product then
flows out of the discharge port 222 back to the source of product. It will be noted
that the discharge port 222 is preferably on the same side of the partition 192 as
is the pipe 193.
[0052] A modification of the valve heretofore described is illustrated in Fig. 16. In cortain
respects the valve of Fig. 16 resembles that shown in Fig. 13 and the same reference
numerals followed by the subscript a are used to designate corresponding parts.
[0053] Product under pressure from a pump or gravity is introduced to one end of Tee 236.
By quick-connect clamps 194a, the end of Tee 236 opposite that through which product
is introduced is connected to a pipe 193a by means of quick-connect clamps 194a or
other means. The pipe 193a passes through partition 192a and is secured thereto by
flange 196a. On the product preparation side of partition 192a is a pressure relief
valve 237. When the outlet of pipe 193a is closed (by means hereinafter explained)
the pressure relief valve 237 opens to permit product to be discharged through port
222a back to the source of product, thereby preventing waste. Valve 237 has a T-shaped
casing 238 formed with a seat 239. Reciprocable within the casing 238 is a valve head
241 which seats on seat 239, having a stem 242 which extends exteriorly of casing
238 and is biased by an adjustable spring 243. In normal operation, the head 241 seats
on the seat 239. However, when the pressure exceeds the force of spring 243, head
241 unseats -i.e., moves to the right as viewed in Fig. 15 , permitting excess product
to flow out through the filler 111. A sleeve 211a is installed in the intake arm of
tho valve 191a, this sleeve having a copical sent 214a against which hood 216a may
seet. Steam 218a of head 216a extends exteriorly of valve 192a to a valve actuator
246. Valve actuator 246 determines the opening and closing of the valve 191a and the
amount of opening thereof to maintain the desired pressure within the filler 111 into
which the valve 191a discharges. Where closure of the head 216a creates nn excessive
pressure in the pipe 193a, the pressure relief valve 237 unseats and excess product
is discharged back to the source of product.
[0054] From the tunnel 61, containers 19 are transferred to the closer 24.
[0055] As seen partially in Fig. 11, closer 24 has an inlet chain 116 which passes around
a sprocket 117 at the distal end of the tunnel 22. Chain 116 has horizontal fingers
118 which are spaced apart a proper distance to feed containers into the turret of
the closer (hereinafter described) and such spacing of fingers 118 is the Same as
the spacing of the spread flights 73. Guides 119 transfer the containers 19 discharged
from the helix 71 into the spaces between the fingers 118.
CONTAINER LID FEED AND STERILIZER
[0056] In addition to the container 19 and product being sterilized and the packing and
lid closing being performed in a sterile atmosphere, it is also necessary that the
container lids 18 be sterilized. In a preferred form of the present invention, a modification
of a Fleetwood Systems, Inc., lid feeder and conveyor 26 is used. One form of such
Fleetwood apparatus is shown in U. S. Patent 4,000,709. Details of the operation of
such apparatus are set forth in the aforesaid patent. Generally, a magazine 136 is
provided having a plurality of cover stack chutes 137 mounted so that the empty chutes
are accessible to the attendant for filli.ng with stacks of lids 18 obtained from
the container man facturing facility. The chutes 137 are mounted so that they are
moved in a rotary pata to one end 138, whereupon the lids 18' in that particular chute
are moved outward into a vertically disposed transfer station 139 which connects with
guides 141 which cause the lids to make a 90 degree curve bend 140 and assume a horizontal
position. As the covers reach the lower end of the bend 140, they are deposited to
rest upon a pair of stainless steel chains 142 driven around sprockets 143 at either
end of the horizontal path. The chains 142 move the lids 18 along the horizontal path
above horizontal partition 146. The return stretch of the chains 142 is below partition
146. After leaving the horizontal stretch, the lids are transferred to an upward inclined
elevator 148 which has a similar chain 149 drive. At the upper end of the elevator
148 is a second 90 degree arcuate bend 151 which communicates with the top of the
cover stack of closer 24, hereinafter described. Where steel lids are used, magnetic
holddowns 152 are used to prevent lids from being forced out of the stack, as well
understood in the industry. Non-steel lids are retained in position by mechanical
means not illustrated herein, but understood in the art.
[0057] Casing 147 is provided around the lower end of the transfer station 139 and continues
around the horizontal lower stretch and the inclined elevator 148 and the bend 151
which leads to the closing machine. The casing 147 preferably has double walls 156
with heat insulation material 157 between the walls 156. Mounted near the machine
is a blower 161, the discharge 162 of which connects to a heater 163, which may be
of various types, typically may be of the electric resistance type. From the heater
163 there is a duct 164 leading to an entrance duct 166 preferably located near the
proximal end of the casing 147. As the lids 18 move through the horizontal and inclined
stretches, hot air circulates around the lids and sterilizes them. Sterility is maintained
until the lids enter the closer 24. Return air is recirculated through return duct
166 below partition 146. Closer 161 draws air from return duct 166. As hereinafter
appears, the closer 24 is also in a sterile atmosphere with non-sterile atmospheric
air excluded by reason of the pressure inside the enclosure of the closer.
CLOSING MACHINE
[0058] The closer 24 shown particularly in Figs. 11 and 12 is an adaptation of the enclosed
closer illustrated and described in Patent No. 3,349,542 except that steam is not
used therein. An enclosure 171 which communicates with the tunnel 71 feed and filler
is double-walled and provided with insulation 172 completely encloses the closer 24.
Since sterile air is forced into the enclosure, the pressure is greater than atmospheric
and this ensures that non-sterile air cannot enter the enclosure. Duct 97 which extends
alongside the conveyor 22 is formed with a bend 173 which communicates with a distributor
174 inside the enclosure adjacent the discharge of the seamed containers.
[0059] The sterilized lids 18 which have been deposited in- to the closer from the lid sterilizer
27 heretofore described are fed one at a time into pockets 176 in the lid turret 177.
Further, containers 19 are advanced by the fingers 118 of the conveyor chain 116 and
are fed into the pockets 178 of the main turret 179 of the closer. The lids 18 on
the lid turret 177 are brought into position over the containers 19 by timed rotation
of the lid turret 177. By means well known in the seamer art, the lifters 181 of the
main turret lift each container 19 into contact with a lid 18 and thereupon seaming
rolls (not shown) attach the lid to the container. The completed container 182 is
then transferred into the discharge star wheel 183 and thence guided by guides 184
out of the system. The details of-the closing machine are not herein illustrated,
being of any of several well-known types. The preferred form herein illustrated is
the Angelus model 60L seamer which is shown partially in said Patent No. 3,349,542.
[0060] One of the features of the closer apparatus is the provision of vertical pipes 186
and 187. Pipe 186 sprays sterile cool water through holes onto the lid push fingers
(not shown) to keep them clean. Sprays 188 of pipe 187 are in a vertical line and
spray sterile, cooled liquid on the container lifter 183 and also on the seaming rolls
(not shown) to prevent build-up of product thereon.
[0061] Although sterile air in the closer 24 is the preferred way of preventing ingress
of atmospheric air, nitrogen or steam (in accordance with conventional practice) may
bo used.
1. A hot air aseptic packaging system comprising
a container sterilizer, said container sterilizer comprising a first casing, a first
conveyor within said first casing, means for feeding empty containers into said first
conveyor, means for discharging containers from said first conveyor, first heating
means, said first heating means comprising a heater for raising the temperature of
air to a sterilizing temperature and blowing means for blowing sterile air above atmospheric
pressure throughout said first casing to sterilize said containers as they pass through
said first conveyor;
a second conveyor section comprising a second casing, a second conveyor in said second
conveyor se tion receiving containers from said first conveyor, a filler, in snid
second casing positioned to fill product into said containers as they travel on said
socond conveyor, means for delivering sterile product into said filler, first trnnnfor
means for discharging sterile filled containers from said second conveyor, means for
maintaining sterile air at above atmospheric pressure within said second casing;
a lid sterilizer comprising a magazine for lids, a third conveyor receiving lids from
said magazine, second heating means for heating air to sterilizing temperature, means
for circulating sterile air at above atmospheric pressure around said lids as they
travel along said third conveyor to sterilize said lids, second transfer means for
discharging sterile lids from said third conveyor,
and an enclosed closer comprising means to receive containers from said first transfer
means, means to receive lids from said second transfer means and position one lid
on top of each container, means for attaching each lid to its respective container,
and moans for discharging closed containers from said closer, and moans for maintaining
pressure in the said closer above atmospheric.
2. A system according to claim 1 in which said first conveyor comprises a belt, a
drum and means for guiding and driving said belt in a continuous helical path around
the exterior of said drum.
3. A system according to either claim 1 or claim 2 in which said second conveyor comprises
a helical conveyor having a first section of a first pitch and a second section of
a second pitch greater than said first pitch, said system accommodating containers
having top outward flaring flanges, said first pitch being less than the cutside diameter
of said flanges to force the flanges of adjacent containers into close proximity,
said filler being disposed above and extending longitudinally of said helical conveyor
above said first section; said filler having a longitudinally extending slit through
which product is continuously discharged in a ribbon into said containers.
4. A system according to any preceding claim which further comprises cooling means
in said second casing to reduce the temperature of said containers.
5. A system according to any preceding claim in which said means for delivering sterile
product comprises means for creating above atmospheric pressure in said product and
a valve between said last-named means and said filler, said valve having a discharge
port, a seat inward of said discharge port, a head shaped to engage said seat, resilient
means biasing said head into engagement with said seat, said head being movable out
of engagement with said seat when the pressure in said valve overcomes the force of
said resilient means, whereby excess product is discharged from said valve through
said discharge port.
6. A method of hot air aseptic packaging comprising:
sterilizing empty containers by conveying said containers in an enclosed first area
while subjecting said containers to hot air at a temperature in the range of 300-400°F
(approx 149-204°C) for a period of time in the range of 60 to 240 seconds,
conveying sterile containers through an enclosed second area in sterile air above
atmospheric pressure, providing sterile product into said second area, filling said
product into said containers, I
sterilizing lids for containers by conveying said lids in an enclosed third area while
subjecting said lids to hot air above atmospheric pressure at a temperature at about
400°F (approx 204°C) for a sufficient period of time to sterilize said lids,
delivering sterile filled container and sterile lids into an enclosed fourth area,
applying said lids onto said containers and securing said lids to said containers.
7. A method according to claim 6 in which said conveying sterile container step includes
forcing said containers close together in a line and then providing said product in
a ribbon above said line to flow into said containers substantially without spillage.
8. A filler for use with a hot air aseptic packaging system comprising,
a tunnel, a straight-line conveyor in said tunnel receiving sterile, empty containers
at a first end and discharging said containers filled with sterile product at a second
end, a filler in said tunnel positioned above said conveyor, first means for delivering
said sterile product to . said filler, second means for delivering sterile air under
pressure to said tunnel,
support means supporting said filler from said tunnel, said filler comprising a casing
extending longitudinally above the path of said containers as they are moved along
said conveyor, said casing being formed at its bottom with an elongated longitudinal
first slit,
a tube of lessor diameter than the interior of said casing disposed within said casing
perforated at its top and connected to said first means, an elongated insert formed
with a second slit disposed in said first slit, and detachable means accuring said
insert to said casing, whereby said insert may be replaced with another insert having
a second slit of different width, product received by said tube flowing into the space
between said tube and said casing, thence out through said second slit and into said
containers.
9. A filler according to claim 8 which further comprises cooling means in said tunnel
to reduce the temperature of said containers.
10. A filler valvo comprising a body having a first inlet port and a first outlet
port and a third port, a first seat in said body between said first inlet and said
first outlet ports, a first head shaped to seal against said first seat, a first stem
fixed to said first head and extending out through said third port, resilient means
biasing said first head against said first seat, said resilient means being adjustable
in force, means for delivering product under pressure from a source to said first
inlet port, means for returning product from said first outlet port to said source;
a second body having a second inlet port connected to said first outlet port, a second
outlet port adapted to bo connected to a filler, and a fourth port; a second seat
in said second body between said second inlet port and said second outlet port, a
second head shaped to seal against said second seat, a second stem fixed to said second
head andiextending out through said fourth port and actuator means connected to said
second stem to move said second head against said second seat and to move said second
head away from said second scat variable distances.