Method for packing a tubular casing length gathered into a hollow cylindrical shirring into a tubular net for subsequent processing as sausage casing in an automatic sausage-making machine

The packing of a tubular casing segment which has been shired together into a hollow cylindrical shirring formation occurs in a tubular net of such configuration that first, with the shirring accomplished with the aid of an abutment which is movable on the shirring tube, a certain initial segment of the tubular casing length is allowed to be left unshirred. Following termination of the shirring, the shirring tube is withdrawn with the abutment from the tubular shirring formation, and the unshirred tubular casing length segment is narrowed down or swaged and is sealed. Finally the sealed tubular casing length tip is inserted with force into the shirring and together with the shirring is thrust through a cylindrical carrier, in which a tubular net is recovered which is sealed to the tubular shirring. This is turned inside out with the thrusting through of the tubular shirring and surrounds this part along its entire length. Finally the tubular net with the tubular shirring incorporated therein is sealed at the other end at two points one after the other in sequence and is separated between said two points. With the further processing of the shirred formation this formation need only be irrigated and the opposite end of the packing need only be torn away, in order to be able to place the shirred formation on the stuffing horn and to be able to begin the filling immediately.

DESCRIPTION 
The invention relates to a method for the packing of a tubular casing 
segment which has been shirred into a hollow cylindrical shirred formation 
in a tubular net for subsequent processing as sausage casing in an 
automatic sausage-making machine. The shirring directly preceding the 
packing occurs on a shirring tube extending into the open end of a tubular 
casing length which shirring tube conducts inflating air into this casing 
length. The tubular casing length is thrust by means of a shirring tool 
with formation of folds against an abutment which gives way in a 
controlled manner and after the desired length of tubular casing length 
has been shirred, it is separated off with removal of the shirring tube. 
Such a method is already known from German Offenlegungsschrift 31 38 685. 
Tubular net package-making arrangements of this type not only guarantee the 
maintenance of the shirring during transport and warehousing before its 
subsequent processing; they also permit rapid and thorough irrigation of 
the shirring at the use site, after the moisture required for the shirring 
has been removed from the shirred formation following its production to 
prevent the multiplication of microbes during transport and warehousing. 
Thus the shirring is to be set aside from the main packing system 
following the irrigation with as little handling as possible and can be 
placed on the stuffing horn of the automatic sausage filling machine ready 
for filling. 
Shirring produced according to known processes only partially fulfills 
these conditions, since the shirred segment is open at both ends and thus 
must first be sealed at the end projecting over the stuffing horn. 
Therefore the packing connected with the shirring by the known method is 
inconvenient and time-consuming and requires a considerable outlay in 
terms of apparatus. 
The object of the invention is to disclose a method of the above type which 
can be carried out more rapidly and with less outlay than the known method 
and in which also one end of the shirred tubular casing segment which is 
incorporated in the tubular net is already sealed. Thus, following the 
irrigation only the opposite end of the package must then be pulled apart, 
in order to be able to fit the shirred formation onto the stuffing horn 
and to immediately begin the filling. 
According to the invention this is attained in that, before the beginning 
of the formation of folds, an initial segment of the tubular casing length 
is thrust over the abutment or cylindrical segment which is slightly 
smaller than the opened tubular casing length until the initial segment of 
the tubular casing length reaches as far as a second sheathing. This 
initial segment then does not to participate in the shirring process. With 
the removal of the shirring tube, the abutment is also removed from the 
unshirred initial segment of the tubular shirred formation and this part 
is narrowed down or swaged and is sealed off. The tip of the tubular 
casing length is then thrust by force into the tubular shirring by means 
of an axial force applied to it and together with the shirring is thrust 
through a cylindrical carrier, from which is recovered a tubular net 
sealed to the tubular shirred part. This tubular net is turned inside out 
during the thrusting through of the tubular shirring and surrounds the 
tubular shirring along its entire length. Finally the tubular net, with 
the tubular shirred formation incorporated therein, is sealed at the other 
end at two points one after the other in sequence and is separated between 
said two points. 
An unshirred tubular casing length segment is formed by the thrusting of 
the initial segment of the tubular casing length over the abutment which 
is used for the shirring, and the unshirred segment can be sealed with 
conventional sealing tools directly following the production of the 
tubular shirring. The subsequent withdrawal and smoothing out of the front 
end of the tubular shirring which has been required until this time for 
the formation of a front seal is no longer necessary for the casing length 
segments to be filled. The tip which is formed by the sealing is then 
pressed by the axial force into the inside of the shirred formation and 
simultaneously this shirred formation is thrust in one pass through the 
cylindrical carrier with the tubular net drawn along in shirred form. The 
unit is thus turned inside out and in turn surrounds the tubular shirring 
along its entire length, so that finally only the other end of the tubular 
net remains to be sealed. The first seal for the next package is produced 
simultaneously and the tubular shirring incorporated in the tubular net 
can be separated from the remaining supply of the tubular net. All of 
these method steps occur in progression in connection with the production 
of the tubular shirring and for execution require quite simple and, 
regarding the sealing, totally conventional means, whereupon the outlay 
for the apparatus remains low. 
According to a first feature for advantageous development of the invention, 
the sealing of the tubular shirred part and of the tubular net is obtained 
with closure or sealing clamps, as is traditional for the most part in 
present-day practice and can be put into practice rapidly and safely, 
using conventional devices. 
Another feature for advantageous development of the invention is provided 
in that the tubular shirring is picked up before removal of the shirring 
tube and the abutment by means on its outside and following its removal is 
moved to the side for execution of further steps of the method. For this, 
the down times between two shirring processes being carried out in 
sequence are short. And with the already known use of turret devices with 
at least two shirring tubes, the shirring of a second casing can already 
be started during the removal of the shirring tube and the abutment from 
the tubular shirred formation. Thus, from the point of view of the turret 
changeover time, there is no further down time interfering with the 
sequence of the process. 
The above development feature of the invention can be further evolved in 
that the narrowing down or swaging of the shirred initial segment of the 
tubular casing length can be carried out in a first side position and the 
forced insertion of the tubular casing length tip and the thrusting 
through the cylindrical carrier in a second side position, so that the 
devices and tools required for the above method steps can remain in their 
original places. 
Still another feature for advantageous development of the invention is 
provided in that the withdrawal of the tubular net from the cylindrical 
carrier is mechanically halted during the thrusting through of the tubular 
shirring. As a result of this, tight packing of the tubular shirring is 
gauranteed and opening out of the folds during transport and warehousing 
as well as also during the subsequent irrigation is most certainly 
avoided. 
Finally, according to a last development feature of the invention, it will 
be advantageous that a cylindrical stamp with flat conical pointed front 
end be used for the forced insertion of the tubular casing length tip and 
the thrusting of the tubular shirring formation through the cylindrical 
carrier, and said pointed front end is preferably withdrawn again into 
starting position before the tubular net is sealed off, while the tubular 
net which is turned inside out is held taut with the tubular shirring 
incorporated therein.

A conventional shirring device is shown diagrammatically in FIGS. 1 to 3 as 
it is used for the production of tubular casing length segments which are 
shirred into shirred formations from a desired length of tubular casing 
length. The tubular casing length 10 emanating in flat state from a (not 
shown) spool passes first between a pair of pressure cylinders 12, which 
seals the tubular casing length. Beyond the pair of pressure cylinders 12 
the tubular casing length 10 is opened by a shirring tube 16 provided with 
a borehole, with inflation air 18 being conducted through borehole 14, and 
fed into the open tubular casing length 10. Inflated tubular casing length 
10 then passes through a shirring tool 20, which is indicated 
diagrammatically with two shirring rollers 22, which narrow down the 
tubular casing length as far as the periphery of the shirring tube and 
with their revolution also push it forward. 
Instead of the two shirring rollers 22 which are shown, three or more 
shirring rollers could be distributed around the periphery of the casing, 
or it could be treated with other types of shirring tools such as for 
instance a rotating powered internal worm, as for instance is already 
known from German Pat. No. 21 47 498. The type of shirring tool being used 
plays no role in the method now being described, since any shirring tool 
will suffice for the thrusting of the tubular casing length material for 
the purpose of producing the shirring. 
FIG. 1 shows the initial position of the tubular casing length before the 
shirring to form a new tubular shirred formation. Pressure cylinders 12 
and shirring tool 20, namely the shirring rollers 22, are stationary, and 
tubular casing length 10 extends some distance over shirring rollers 22, 
where it is held open by inflation air 18 being introduced from borehole 
14 with approximately the same spacing from shirring tube 16 all the way 
around. Shirring tube 16 can be mounted with its other end in a holder 24, 
which is indicated in FIGS. 1 to 3 as a plate, which can be moved by a 
(not shown) power cylinder in longitudinal direction along shirring tube 
16. Instead of the plate, the shirring tube can also be mounted with 
another or even several more shirring tubes in an axially movable turret 
device, as is known for instance from German Offenlegungsschrift 29 24 
059. 
A sheathing abutment 26 is arranged movably on shirring tube 16, and the 
sheathing abutment 26 has a cylindrical (first abutment) segment 28 
tapering into shirring tool 20. The thicker (second abutment) collar 30 
remaining at the opposite end of sheathing abutment 26 can be grasped by a 
forked vise 32 and be thrust in a controlled manner over shirring tube 16 
by a (not shown) power cylinder along shirring tube 16. 
In FIG. 1, in which shirring tube 16 is inserted completely into the opened 
end of tubular casing length 10, the sheathing abutment 26 is located with 
its tapered segment 28 directly before the opening of the tubular casing 
length and because of the inflation air centering the casing length can be 
inserted with some force into this casing directly before shirring tool 
22. 
Then the shirring begins, and shirring rollers 22 are set in rotation by a 
(not shown) drive arrangement and the tubular casing length material is 
thrust toward sheathing abutment 26. Thus an initial segment 34 of tubular 
casing length 10 remains unshirred on the tapered part 28 of sheathing 
abutment 26, of which the cross section is configured to be only slightly 
smaller than the inside diameter of the opened tubular casing length. As 
soon as the end of tubular casing length 10 engages against collar 30, 
tubular casing length 10 begins to form folds before tapered part 28 of 
sheathing abutment 26, and there forms a shirred formation 36. Shirred 
formation 36 becomes longer and longer with increased thrusting of the 
tubular casing length, while at the same time abutment sheathing 26, 
controlled by the vise, falls back before this length increase. 
When finally the desired length of shirring has been reached, as shown in 
FIG. 3, the shirring 36 is moved further forward with the aid of shirring 
tube 16 and sheathing abutment 26 for some distance. Then, an unshirred 
tubular casing length area 38 appears before shirring rollers 22, from 
which tubular shirring 36 can be separated from tubular casing length 10 
by a cutting instrument, for instance a pair of blades 40. In this 
position shirring tube 16 is completely withdrawn from shirring tool 20 
and now for instance with the aid of the aforementioned turret can be 
brought into an offset position off to the side from shirring tool 20. 
Tubular shirring formation 36 according to FIG. 4 is then picked up by a 
holding device 42, for instance a prism forceps. Prism forceps 42 
facilitate separation of the tubular shirring formation 36 from abutment 
sheathing 26, and either the sheathing is moved further upward or the 
prism forceps are drawn downward with the tubular shirring. Thus the 
unshirred tubular casing segment 34 is free at the top end of tubular 
shirring 36 and can be narrowed down or swaged as shown in FIG. 5, and 
then can be sealed, for instance by a closing clamp 44 with the aid of a 
(not shown) known clamp device. 
Tubular shirring 36 can be sealed onto the unshirred tubular casing length 
segment 34 in the same setting in which sheathing abutment 26, as shown 
before in FIG. 4, had been separated from shirring 36. Shirring 36 however 
can also be brought with the aid of prism forceps 42 into another side 
offset position for the sealing, from which the sealed shirred formation, 
again with the aid of the prism forceps, is brought into a packing 
position as in FIG. 6. In this packing position, tubular shirring 36 is 
located on the same axis between a cylindrical stamp 46, of which the end 
48 for use with the shirring is configured to be flat and conical. and a 
packing device 50, which consists of a cylindrical carrier 54 provided 
with a collar 52 at the bottom end. It should be appreciated that tubular 
shirring 36 is recovered on the one tubular net 56 from the top of the net 
downward. The top end of tubular net 56 is sealed by a closing clamp 58 
and is drawn through and downward while it is simultaneously turned inside 
out, until the sealed end projects out of carrier 54. 
Stamp 46 is located on a rod 60 and can be moved axially back and forth 
with said rod by a (not shown) power cylinder. 
As soon as prism forceps 42 with tubular shirring 36 therein have reached 
the position shown in FIG. 4, prism forceps 42 are slightly opened, and 
stamp 46, as shown in FIG. 7, moves downward. The flat conical end 48 of 
the stamp then initially inserts the closing tip 62 of the tubular 
shirring formed by sealing clamp 44 with some force into the top of this 
tubular shirring, and then thrusts the entire tubular shirring into the 
sheathing-like carrier 54 and through this carrier into the position shown 
in FIG. 8. Thus the bottom end of tubular shirring 36 picks up the tubular 
net end having clamp 58 which carrier or net is turned inside out and 
draws this end further from the sheathing-like carrier over its top edge. 
Thus the entire tubular shirring, as shown in FIG. 8, is finally 
incorporated by a portion of tubular net 56. 
Now stamp 46 is again moved back into the starting position, while tubular 
shirred formation 36 incorporated into the tubular net is held back by a 
not shown holding device in the position shown in FIG. 8. A shirring-free 
segment is then formed between the bottom end of cylindrical carrier 54 
and the incorporated tubular shirring 36. This segment is sealed following 
suitable narrowing down by means of two closing clamps 64, 66 and between 
clamps 64 and 66 and is separated off by a blade 68. Thus, as is clear in 
FIG. 9, a tubular shirring 70 is disclosed as completely incorporated in a 
tubular net and sealed at the top end, while other tubular net material 
again occupies the original starting position as shown in FIG. 6 for the 
introduction and sealing of the next tubular shirring.