Apparatus for producing and applying a protective covering to a cut edge of an opening of a container wall

For an opening for a container wall, a rivet-shaped protective covering is made and applied by an apparatus. A sheet-like piece of foil is laid down by all applying device on a first wall area bordering the opening. The section overlapping the opening is formed into the opening by a first forming device. A part of the section projects out of the opening at a second wall area bordering the opening. The part of the foil piece projecting out of the opening is formed against the second wall area by a second forming device, whereby the rivet-shaped form of the foil piece is maintained. The rivet-shaped protective covering is affixed permanently to the container wall by an affixing device.

CROSS-REFERENCE TO RELATED APPLICATIONS 
This application is related to application Ser. No. 08/545,094 filed on 
Oct. 19, 1995 in the name of Werner STAHLECKER for CONTAINER COMPRISING A 
CONTAINER BODY T AND A FRONT WALL CONNECTED THERETO. 
BACKGROUND AND SUMMARY OF THE INVENTION 
The present invention relates to an apparatus for producing and applying a 
protective covering for a wall opening of a container, whereby the edge of 
the opening and both edge areas of the two wall areas of the wall 
bordering the edge are covered in a rivet-like manner by the protective 
covering. 
U.S. Pat. No. 4,397,401 describes a rivet-shaped protective covering made 
from two sheet-like pieces of foil. The two pieces of foil are fed to the 
container wall containing the opening. One foil piece is applied to one 
wall area bordering the edge of the opening, and the other foil piece is 
applied to the other wall area bordering the edge. Thereby, the opening of 
the wall is completely covered by each foil piece. Covering of the edge of 
the opening takes place in that one foil piece or both foil pieces are 
formed into the opening. Both foil pieces are melted together in the edge 
area to produce a uniform protective covering. An opening is made in both 
foil pieces whose diameter is somewhat smaller than the diameter of the 
original opening of the container wall comprising the uncovered cut edge. 
Unpublished German patent application Serial No. P 44 11 925.9 describes a 
rivet-shaped protective covering for an opening of a container wall which 
is made from only one foil piece. In one embodiment, a sheet-like foil 
piece is applied to a first wall area so that the opening and the edge 
area of the wall bordering the opening are covered. The section of the 
foil piece covering the opening of the wall can be provided with an 
opening whose diameter is smaller than that of the wall opening. The 
section of the foil piece covering the wall opening is formed into the 
opening such that a tube-shaped section of the foil piece is formed and 
projects slightly out of the wall opening at the second wall area. This 
section of the foil piece projecting out of the opening is formed towards 
the second wall area so that the rivet-shaped form of the foil piece is 
maintained. The foil piece is attached permanently to the wall and thus 
forms a rivet-like protective covering. 
It is an object of the present invention to provide an apparatus for making 
a rivet-shaped protective covering comprising only one foil piece, and 
which can be applied to a wall opening in a container. 
The foregoing object has been achieved in accordance with the present 
invention by an apparatus which comprises a device for applying a 
sheet-like foil piece to the first wall area, a device for forming a 
section of the applied foil piece overlapping the wall opening in through 
same, a device for forming a section of the formed foil piece which 
projects out of the wall opening at the second wall area, and a device for 
permanently attaching the foil piece formed into a rivet-shaped protective 
covering. 
The device of the present invention advantageously enables a simple and 
reliable manufacturing and application of a rivet-shaped protective 
covering. 
The present invention can be applied to all container walls where a 
substance, in particular the container contents, must be prevented from 
leaking into the container wall. In the opening area, the wall surface is 
often broken open, in particular when the opening is made by cutting or 
punching. By applying the protective covering, a similar or identical 
protection, as found in other areas of the container, can be made in the 
edge area. 
It is not important in which of a plurality of container walls the opening 
is present or whether the container consists of a plurality of walls. 
The wall comprising the protective covering at the opening can be made into 
a container of varying forms and, for example, be fed to a 
container-producing machine. 
"Foil" as used herein means all sheet material which is formable, whereby 
the thickness of the material is irrelevant. Insofar as no heat is used 
for the forming device, it is sufficient for the foil to be formed cold. 
The wall to which the protective covering is to be applied can be already 
provided with an opening when it is fed to the apparatus. It is also 
possible to provide the apparatus with a device for making the opening in 
the wall. 
A foil piece without broken-through areas for openings can be used for 
making the protective covering. It is, however, also possible to use a 
foil piece with an opening. A foil piece in which there is an opening can 
then be fed to the apparatus. It is also within the scope of the present 
invention to arrange a device to the apparatus with which an opening can 
be made in the foil piece. The making of the opening can take place 
before, during or after the forming of the foil piece. The presence of an 
opening in the foil piece intended for forming can be useful when only 
mechanical forming devices are used. 
The foil piece can be affixed in one or several production stages. It is, 
for example, possible to permanently affix the foil piece to the first 
wall area simultaneously during application, to then form the foil piece 
and finally to affix the formed section of the foil piece to the second 
wall area of the wall. It is also possible instead to affix the foil piece 
to the wall areas and if required in addition, to the edge of the opening, 
after it has been formed. 
In one advantageous embodiment, the apparatus is provided with a device for 
temporarily holding the foil piece fast. This device is above all 
purposeful when a part of the foil piece is not already permanently 
affixed before forming. While the foil piece is being temporarily held 
fast, it can be securely formed without slipping out of place due of the 
effect of the various devices. The unformed foil pieces can also be fed 
individually to the apparatus. 
Advantageously, the apparatus is fed a large piece of plane foil and is 
provided with a device for cutting out sheet-like foil pieces from the 
plane foil. The plane foil can be fed for this purpose in the form of a 
tape, in which there is a plurality of sections corresponding to foil 
pieces, which can be cut out of the tape in the apparatus. 
The various devices of the apparatus can be installed in a single 
processing station or in a plurality of processing stations. In an 
advantageous embodiment, the device for separating a foil piece, the 
device for applying the foil piece, the device for holding the foil piece 
fast, the device for forming the section overlapping the wall opening and 
the device for forming the section projecting out of the opening are 
arranged at one processing station, while the device for affixing the foil 
piece formed into a rivet-shaped protective covering is arranged at 
another processing device. The processing station for affixing is arranged 
downstream of the first mentioned processing station in relation to the 
processing stages. 
The device for separating a foil piece can comprise a die plate with a 
recess corresponding to the outer contour of the uncut foil piece and a 
blanking punch corresponding to the outer contour of the foil piece. The 
blanking punch can slide from one position outside of the die plate to a 
position inside the recess of the die plate. 
In a further embodiment, the application device comprises a device for 
transporting the foil piece, which is advantageously formed by the 
blanking punch. The blanking punch can be guided through the recess in the 
die plate to the first wall area. The circumferential wall of the recess 
acts then as a guiding surface for the foil piece while being transported 
to the wall. 
The device for forming the section overlapping the opening of the wall can 
also comprise a supporting plate with a recess whose contour corresponds 
at least approximately to the contour of the opening of the wall and into 
which recess a drawing punch can be guided, whose outer contour 
corresponds approximately to the contour of the recess. Due to the 
essentially corresponding contours, the section of the foil piece which 
has been formed into the opening receives a shape corresponding to the 
opening and can be laid against the edge. 
The diameter of the drawing punch can be slightly narrower than the 
diameter of the opening of the wall and the recess in the supporting 
plate. A deviation in the diameter size can be practicable in order to 
leave sufficient room between the edge of the wall opening and the drawing 
punch for the formed foil piece. It can also be advantageous not to make 
the diameter of the drawing punch narrower than the diameter of the wall 
opening, for example, when the wall is not rigid. 
In an advantageous embodiment, the drawing punch has a smaller diameter at 
its front end to aid the formation of the plane, overlapping section into 
the opening. 
The front end of the drawing punch can be made to match an opening arranged 
in the foil piece. This also aids the forming of the plane, overlapping 
section of the foil piece into the wall opening. This measure is 
particularly advantageous when forming is done cold. 
The device for holding the foil piece fast can be formed by the blanking 
punch, which is guided to the first wall area, and by the supporting 
plate. The device for forming the section of the foil piece projecting out 
of the wall opening comprises a bordering punch, which can be slid into an 
opening of the above mentioned section of the foil piece and whose outer 
contour is so shaped that the above mentioned projecting section is 
expanded and formed towards the second wall area when the bordering punch 
slides into position. 
It is useful to place the bordering punch on the drawing punch so that, 
when the drawing punch slides, the bordering punch moves therewith. This 
aids forming because the section of the foil piece projecting out of the 
opening is transferred from the drawing punch to the bordering punch 
without interruption. 
The outer contour of the bordering punch can correspond at least 
approximately over a longitudinal area to the contour of the wall opening. 
Advantageously, the bordering punch has a longitudinal area, beginning at 
its front end and extending essentially axially, and a ring surface, 
adjoining outwards thereto, with essentially radial direction components. 
The longitudinal area extending essentially axially penetrates into the 
inside of the essentially tube-shaped section of the foil piece which 
projects out of the opening during the sliding movement of the bordering 
punch, and guides the foil piece to the ring surface. The ring surface 
presses the projecting section against the wall area. 
The bordering punch ban have an approximately constant diameter in a 
central longitudinal area, which diameter is slightly narrower than the 
diameter of the wall opening. A front longitudinal area with a diameter 
tapering towards the front end of the bordering punch advantageously 
adjoins the central longitudinal area of the bordering punch. The transfer 
by the bordering punch of the tube shaped section projecting out of the 
wall opening is simplified. 
The area of the bordering punch, at which the essentially axially extending 
longitudinal area goes over to the ring surface with radial direction 
components, is also advantageously formed by a circumferential surface 
which forms a ring-shaped groove recess in the ring surface. The forming 
of the section of the foil piece which projects out of the wall opening to 
the second wall area is thus simplified. 
The supporting plate is formed from a plurality of sub-plates which are 
movable away from the center of the recess in radial direction of the 
recess of the supporting plate. Space is thus simply made for the 
bordering punch to press the foil piece against the second wall area. The 
blanking punch is formed as a tube, in whose hollow area the drawing punch 
is freely suspended.

DETAILED DESCRIPTION OF THE DRAWINGS 
In the process shown in FIG. 1, a tape 1 of coated cardboard is unwound 
from a roll (not shown) in a known way and fed to a first processing 
station 5 in the direction of the arrow A. The tape 1 comprises a 
plurality of sections, arranged one behind the other (represented by 
dot-dash lines), each of which sections correspond to a wall 2 for a 
container. Each wall 2 of the tape 1 is provided with an opening 3, whose 
edge 4 is to be provided with a protective covering 12. After the 
protective covering 12 has been applied as described below, the tape 1 is 
wound up onto a roll (not shown) in a known manner which is fed to a 
machine for producing cans. 
For the production of the cans, the walls 2 with the protective covering 12 
will be punched out along the dot-dash line and further processed into 
lids for the cans. This process is not further described here as it forms 
no part of the present invention. 
The above mentioned processing station 5 is fed a tape-shaped foil 6 from a 
roll (not shown), which foil 6 is preferably polyethylene. The foil 6 
comprises a plurality of sections which each correspond to a foil piece 7 
and which can be cut out from the tape-shaped foil 6 along the dot-dash 
line. Each foil piece 7 of the tape-shaped foil 6 is provided with an 
opening 8 whose contour corresponds to the contour of the opening 3 of the 
wall 2. The opening 8 has, however, a smaller diameter than the wall 
opening 3. At the processing station 5, each of the sections of the 
tape-shaped foil 6 which correspond to a foil piece 7 are fed to one 
section, corresponding to the wall 2, of the cardboard tape 1. The 
sections of the foil 6 and the tape 1 are positioned facing each other in 
such a way that an opening 8 aligns with and faces an opening 3 at a 
distance. The section of the foil 6 so positioned is punched out as foil 
piece 7 and lies against the wall 2. As the outer circumference of the 
foil piece 7 is somewhat larger and the diameter of the opening 8 of the 
foil piece 7 somewhat smaller than the opening 3 of the wall 2, the foil 
piece 7 forms a ring-shaped section 10 overlapping the opening 3 and a 
border section 9 projecting over the edge area of the wall 2. 
At the processing station 5, the cut out foil piece 7 is formed in such a 
way that, after it has been applied to the wall 2, the opening 3 of the 
wall 2 is covered in rivet-like fashion. The wall 2, provided with the 
rivet-shaped foil piece 7, is transported further, together with the tape 
1, to a processing station 11. There the rivet-shaped foil piece 7 is 
affixed permanently in a leakproof way to the wall 2, so that a 
rivet-shaped protective covering 12 is formed. The individual production 
stages are described below with the aid of FIGS. 2a to 2e. The production 
and application of the rivet-shaped protective covering 12 can be done by 
an apparatus whose construction and function is described in FIGS. 3 and 
4a to 4d. 
As can be seen from FIGS. 2a to 2e, the wall 2 to which the protective 
covering 12 will be applied comprises a carrier layer 13 of cardboard and 
two protective layers 14, 15 which are preferably polyethylene. The 
protective layer 14 forms the surface of a first wall area 16 bordering 
the edge 4, and the protective layer 15 forms the surface of a wall area 
17 bordering the edge 4. The edge 4 of the opening 3 of the wall 2 is not 
covered by a protective layer. 
In the production stage shown in FIG. 2a, the fed foil 6 is brought into 
the above-discussed position, namely the openings 3 and 8 being aligned. 
Opposite the foil 6, a foil piece 7 lies at a distance and corresponds to 
the section of the foil 6 of the first wall area 16. 
In the production stage shown in FIG. 2b, the foil piece 7 of the foil 6 is 
cut therefrom and applied to the first wall area 16 of the wall 2, so that 
it covers the opening 3 and the thereon bordering edge area 23 of the wall 
2. The edge section 9 covering the edge area 23 and the section 10 
overlapping the opening 3 are thereby formed as already mentioned above. 
The foil piece 7 is now pressed against the first wall area 16 of the wall 
2. 
In a subsequent production stage, shown in FIG. 2c, the overlapping section 
10 is formed through the opening 3 so that a section 18 remaining at the 
first wall area of the wall 2 and corresponding to the edge section 9 is 
formed, and a formed, tube-shaped section 19 is also formed. The 
tube-shaped section 19 comprises a section 20 covering the edge 4, and a 
section 21 projecting out of the opening 3. The section 21 terminates at 
the front side with an opening 25. 
In a next production stage, shown in FIG. 2d, the projecting section 21 is 
formed in the direction towards the second wall area 17 of the wall 2 so 
that a further plane section 22 is formed in the foil piece 7. The foil 
piece 7 now has a rivet-shaped form and lies, unaffixed, in the area of 
the opening 3. 
In the production stage shown in FIG. 2e, the rivet-shaped foil piece 7 is 
affixed to both wall areas 16, 17 and additionally to the edge 4 by heat 
sealing. The foil piece 7 now forms the rivet-shaped protective covering 
12. 
The above-described production stages shown in FIGS. 2a to 2d are executed 
in the first processing station 5, and the production stage described in 
FIG. 2e is executed in the second processing station 11 (FIG. 3). The 
apparatus shown in FIG. 3 comprises both the first processing station 5 
and the second processing station 11. 
The processing station 5 comprises a device 30 for separating the foil 
piece 7, a device 40 for applying the cut out foil piece 7, a device 50 
for forming the overlapping section 10 of the foil piece 7, a device 60 
for forming the section 21 projecting out of the opening 3 and a device 70 
for holding fast the cut out foil piece 7. The processing station 5 will 
now be described with reference to FIGS. 4a to 4d. 
The second processing station 11 comprises a device 80 for affixing the 
rivet-shaped foil piece 7 to the wall 2. The device 80 is an ultrasonic 
welding device and comprises a sonotrode 81 as well as an anvil 82 
cooperating therewith. The sonotrode 81 includes an insert 83 whose 
contour corresponds to the contour of the opening 3 and whose diameter is 
somewhat smaller than the diameter of the opening 3. The insert 83 
projects into the opening 3 and fills it almost completely. 
As can be seen in FIG. 3, the processing station 5 is fed a wall 2 whose 
opening 3 is to be covered by a foil piece 7 from a fed foil 6. The foil 
piece 7 is formed into the desired rivet shape at this processing station 
5 as described below with reference to FIGS. 4a to 4d. 
At the processing station 11, the rivet-shaped formed foil piece 7 is 
affixed to the wall 2 by the ultrasonic welding device. The necessary heat 
for welding is generated by the sonotrode 81 and the anvil 82. The 
sonotrode 81 lies on the first wall area 16 and the anvil 82 on the second 
wall area 17 against the rivet-shaped formed foil piece 7. The insert 82 
prevents the heated material of the foil piece 7 from running inside the 
opening 3. 
FIGS. 4a through 4d show the components used to form the foil piece 7 in 
various working positions. The construction and arrangement of the 
components will be described below with specific reference to FIG. 4a, 
while the function of the components will be described with reference to 
FIGS. 4b to 4d. 
The separating device 30 includes a die plate 31 which, in turn, comprises 
a recess 32 whose contour corresponds to the contour of the uncut foil 
piece 7. The recess 32 is guided through the die plate 31. Under the die 
plate 31, the wall 2 designated to receive a protective covering 12 is 
positioned in such a way that the opening 3 is aligned exactly with the 
recess 32. The cross-sectional area of the recess 32 is larger than the 
cross-sectional area of the opening 3, so that the edge area 23 of the 
wall 2 lies uncovered. The device 30 further has a blanking punch 33 whose 
outer contour corresponds to the contour of the recess 32. The blanking 
punch 33 can be guided into the recess 32 to the wall area 16 of the wall 
2. The blanking punch 33 has a tube-shaped form and includes a hollow area 
34. 
The device 40 for applying the cut out foil piece 7 comprises a device 41 
for transporting the foil piece 7 which is formed by the blanking punch 
33. The blanking punch 33 can be guided through the recess 32 to the first 
wall area 16 of the wall 2 and thus transport the cut-out foil piece 7. 
The circumferential wall of the recess 32 can serve as a guiding surface 
for the foil piece 7 while it is being transported to the wall 2. 
The device 50 for forming the section 10, as also seen in FIG. 4b, 
overlapping the opening 3 of the wall 2 comprises a supporting plate 51 
with a recess 52 as well as a drawing punch 53. The drawing punch 53 is 
movable in the hollow area 34 formed inside the tube-shaped blanking punch 
33 and can be guided into the recess 52 of the supporting plate 51. The 
contour of the recess 52 corresponds at least approximately to the contour 
of the opening 3 of the wall 2. The contour of the drawing punch 53 
corresponds in diameter at least approximately to the contour of the 
recess 52. The cross-sectional area of the drawing punch 53 is slightly 
smaller than the cross-sectional area of the opening 3 of the wall 2 and 
the recess 52 of the supporting plate 51. The section 19 of the foil piece 
7 formed into the opening 3, as seen also in FIG. 4c, is left sufficient 
space between the edge 4 of the opening 3 of the wall 2 and the drawing 
punch 53. 
The circumferential wall of the drawing punch 53 extends over a central 
longitudinal area 58 parallel to the axis 90 of the drawing punch 53. The 
cross-sectional area of the drawing punch 53 is narrower at its front end 
54 than at its central longitudinal area 58. As a result, the 
circumferential wall extends with an incline towards the axis 90 in the 
front longitudinal area 59 of the drawing punch 53. This construction of 
the front longitudinal area 59 and the front end 54 of the drawing punch 
53 is adapted to the foil piece 7 comprising an opening 8, and facilitates 
forming into the opening 3 of the wall 2. 
The supporting plate 51 is divided into four sub-plates, which can be moved 
away from the axis 90. Of the four sub-plates of the supporting plate 51, 
only sub-plates 55, 56, 57 are shown. The device 70 for holding the foil 
piece 7 fast or secure is formed by the blanking punch 33, which is guided 
to the first wall area 16 of the wall 2, and the supporting plate 51. 
The device 60 for forming the section 21 of the foil piece 7 which projects 
out of the opening 3 of the wall 2 comprises a bordering punch 61 which 
can be slid into the opening 3 of the wall 2 and cooperates with the 
drawing punch 53. The bordering punch 61 can be applied to the front end 
65 of the drawing punch 53 so that when the bordering punch 61 slides into 
the opening 3, the drawing punch 53 moves therewith. The bordering punch 
61 is movable along a guiding mandrel 68 in order to enable it to execute 
the sliding movement. 
The outer contour of the bordering punch 61 corresponds at least 
approximately over a central longitudinal area 63 and a front longitudinal 
area 64 to the opening 3 of the wall 2. The outer circumferential wall of 
the bordering punch 61 extends at the front longitudinal area 64 and the 
central longitudinal area 63 essentially parallel to the axis 90. The 
circumferential wall extends, however, with a slight incline towards the 
axis 90 in the direction towards the front end 65 of the bordering punch 
61. In the other direction, a ring surface 66 is joined to the central 
longitudinal area 63 comprising essentially radial direction components. 
In the central longitudinal area 63, the diameter is at least approximately 
constant and slightly narrower than the diameter of the opening 3 of the 
wall 2. The cross-sectional area tapers continuously in the direction to 
the front end 65 due to the inclined course of the circumferential wall in 
the front longitudinal area 64, and is narrower than the diameter of the 
central longitudinal area 63. 
The bordering punch 61 comprises a circumferential surface 67 in the area 
in which the central longitudinal area 63 graduates into the ring area 66 
with radial direction components. The circumferential surface 67 forms a 
ring-shaped groove in the ring area 66. 
The blanking punch 33 is located at a position 33' in FIG. 4a outside of 
the recess 32 of the die plate 31. The foil 6 lies on the die plate 31. 
The wall 2 lies on the supporting plate 51 and is supported thereby. The 
wall 2 and the foil 6 take up the position in FIG. 2a described above. 
The blanking punch 33 is now moved in the direction of arrow B, as seen 
also in FIG. 4b, when the foil piece 7 is to be cut out of the foil 6, 
until the blanking punch 33 has reached position 33'. With the movement of 
the blanking punch 33, the foil piece 7 is cut out from the foil 6 as soon 
as the blanking punch 33 passes the upper edge of the recess 32 of the die 
plate 31. The blanking punch 33 transports the cut out foil piece 7 during 
this movement inside the recess 32 up to the wall area 16 of the wall 2, 
so that the foil piece 7 rests against the first wall area 16 of the wall 
2 in the edge area 23. When the foil piece 7 is being transported to the 
wall 2, the inner wall of the recess 32 serves as a guiding surface for 
the foil piece 7. 
The blanking punch 33 remains in the position 33", and exercises a light 
pressure in the direction of the arrow B. The foil piece 7 takes up the 
position shown in FIG. 2b and is temporarily held fast by the nipping 
effect of the blanking punch 33 with the supporting plate 51, on which the 
blanking punch 33 is supported by way of the wall 2. The drawing punch 53 
remains in the position 53' shown in FIG. 4b during the above-described 
processing stages. 
In the processing stage shown in FIG. 4c, the drawing punch 53 is slid in 
the direction of the arrow B into the position 53". The section 10 of the 
foil piece 7, as also seen in FIG. 4b, overlapping the opening 3 is hereby 
formed into the opening 3 of the wall 2. The foil piece 7 attains the 
shape shown in FIG. 2c, that is, a tube-shaped section 19 is formed, of 
which a section 20 covers the edge 4 of the opening 3 and a section 21 
projects out of the opening 3 of the wall 2. The section 21 projecting out 
of the opening 3 of the wall 2 lies hereby against the inner wall of the 
recess present in the supporting plate 51 as shown in FIG. 4a. 
As a result of the movement of the drawing punch 53 into the position 53", 
the opening 8 of the foil piece 7 shown in FIG. 4b is expanded in such a 
way that the formed, tube-shaped section 19 of the foil piece 7 forms a 
front side opening 25 as seen in FIG. 2c, whose diameter corresponds at 
least approximately to the diameter of the drawing punch 53. 
In the working position shown in FIG. 4c, the sub-plates 55, 56 take up the 
positions 55', 56', whereas the sub-plates 57 (not shown in FIG. 4c) also 
take up relevant positions. The bordering punch 61, including its front 
longitudinal area 64, the central longitudinal area 63, the ring area 66 
and the circumferential surface 67 take up the positions 61', 64', 63', 
66', 67' shown in FIG. 4c. 
In the processing stage shown in FIG. 4d, the section 21 previously seen in 
FIG. 4c projecting out of the opening 3 of the foil piece 7 is formed 
towards the second wall area 17 of the wall 2. The bordering punch 61 is 
slid in the direction of the arrow C in the position 61". During the 
sliding movement of the bordering punch 61, the drawing punch 53 moves 
with it and is guided over into the position 53"'. The sub-plates 55, 56 
of the supporting plate 51 are moved radially outwards in the direction of 
the arrows E, D into the positions 55" and 56", so that the bordering 
punch 61 is not hindered in its sliding movement. The sub-plates 57 (not 
shown) are moved radially outwards in the same way as the sub-plates 55, 
56. 
During the sliding movement of the bordering punch 61, its front 
longitudinal area 64, which has a relatively narrow cross-section area, 
moves through the opening 25 into the inside of the tube-shaped section 19 
seen in FIG. 4c. With further sliding of the bordering punch 61, its 
central longitudinal area 63 also moves into the inside of the tube-shaped 
section 19. Finally, with further sliding, the circumferential area 67 
reaches the front edge of the tube-shaped section 19 bordering the opening 
25. There the front edge of the tube-shaped section 19 is formed radially 
outwards and with the aid of the essentially radially extending ring 
surface 66 pressed against the second wall area 17 of the wall 2. 
The sliding movement of the bordering punch 61 in the direction of the 
arrow C in FIG. 4d now comes to an end. The bordering punch 61, the front 
longitudinal area 64, the central longitudinal area 63, the 
circumferential area 67 and the ring area 66 take up the positions 61", 
64", 63", 67" and 66". The foil piece 7 now has the rivet-shaped form as 
shown in FIG. 2d. 
The blanking punch 33, the drawing punch 53 and the bordering punch 61 
thereafter withdraw, thus releasing the wall 2 with the rivet-shaped foil 
piece 7 from the processing station 5 and leaving it free for 
transportation to the processing station 11. At the processing station 11, 
the rivet-shaped foil piece 7, as described above, is affixed to the wall 
2 by heat sealing. 
Although the invention has been described and illustrated in detail, it is 
to be clearly understood that the same is byway of illustration and 
example, and is not to be taken by way of limitation. The spirit and scope 
of the present invention are to be limited only by the terms of the 
appended claims.