Metal working – Method of mechanical manufacture – Electrical device making
Reexamination Certificate
2002-10-31
2004-10-19
Williams, Hezron (Department: 2856)
Metal working
Method of mechanical manufacture
Electrical device making
C073S588000
Reexamination Certificate
active
06804873
ABSTRACT:
The present invention departs from problems which are encountered in manufacturing filled containers and as will be exemplified referring to
FIGS. 1
to
10
.
In
FIG. 1
there is shown a container
1
which comprises a first part
1
a
and a second part
1
b.
The first part
1
a
is conceived as a receptacle and is filled with a product P as e.g. with a foodstuff, e.g. yoghurt. The second part
1
b
is conceived as a covering foil or lid, which is sealingly bonded to the part
1
a
along a bond area
3
.
In top view the container
1
may have a great variety of shapes, some examples being shown in
FIGS. 2
to
4
. According to
FIG. 2
the container
1
as of
FIG. 1
is cylindrical or cone shaped and the bond area
3
is circular.
According to
FIGS. 3 and 4
the container
1
has a shape departing from circular, conceived with a shape resulting from fantasy of the container manufacturer. There the shape of the bond area
3
largely departs from circular and may in fact have practically any looped shape.
According to
FIG. 5
the container
1
with an outer shape e.g. as shown in
FIG. 1
has a part
1
a
which is filled e.g. with two filling products P
a
and P
b
in two respective compartments which are separated by a separating wall
5
, e.g. being an integral part of the container part
1
a.
Accordingly the bonding area
3
by which the second part
1
b
is sealingly bonded to the part
1
a
of the container
1
has, as shown in top view in
FIG. 6
, not only a looping area but additionally an area which crosses that loop.
FIGS. 7 and 8
show, departing from the container shapes as exemplified in the
FIGS. 3 and 4
, such containers and the resulting bonding area
3
when e.g. their part
1
a
according to
FIG. 1
is subdivided by additional walls into two or more than two distinct compartments. From
FIGS. 1
to
8
it results that the bonding area
3
may have practically any shape.
Further, and as shown in
FIG. 9
, the second part of a container
1
needs not be a foil or lid part, but may be a second receptacle part. According to
FIG. 9
the container
1
comprises part
1
a
formed as a receptacle and part
1
c
formed as a receptacle too. These two parts are bonded along bond area
3
. Thereby, the container
1
may contain one single product, so that no separation is provided within container
1
. If the container
1
contains e.g. two products P
a
and P
b
, which shall not be mixed within the container
1
, one or even two separating foils
7
are provided and the bond area
3
preferably links the parts
1
a,
1
c
as well as the foils
7
. Additionally, the technique as shown in
FIG. 9
may be combined with subdivision of the parts
1
a
and/or
1
c
by walls as shown in
FIGS. 5
to
8
.
All the bond areas
3
as exemplified in the
FIGS. 1
to
9
have in cross-section as shown in
FIG. 6
at X—X the structure as shown in FIG.
10
. Two or more than two, according to
FIG. 10
e.g. three, materials A, B, possibly C . . . are as schematically shown bonded together at the bond area
3
, which is in said cross-sectional view substantially flat. Thus, the bonding area
3
is in fact band-shaped. Bonding may be done by any known technique for the addressed purpose, as by gluing, welding etc. More specifically bonding may be performed in a preferred form by ultrasonic sealing, high frequency sealing or heat contact sealing. In this context the addressed “bonding” is often referred to e.g. in literature as “sealing”. Further, the material as of A, B, C . . . of
FIG. 10
may be, considered in subsequent pairs, equal or different, thereby being e.g. plastic material, metal material as of aluminum for foils, coated metal material etc.
We define generically surfaces along which two material phases contact each others, even if the contacting materials are equal and just lay one upon the other, as material interfaces. Thus, according to
FIG. 10
a first material interface is formed between material C and ambient air, a second between material B and material C and a third between material A and B, a fourth again between ambient air and material A.
By the addressed bond areas
3
one or more than one filling product of the container
1
are encapsulated. If the bond area
3
does not provide for a high quality joint and according to the degree of bonding failure, air may be entrapped or filling product may pour out of the container
1
more or less rapidly or become entrapped too within the bond, and may start to deteriorate over time. Also other contaminants may be entrapped in the bond area. Depending on the kind of product contained in such containers, e.g. medical products, food products, a locally inaccurate or disturbed bondage along the bond areas
3
may cause tremendous problems. Thereby, an inaccurate bond along the bond area needs not necessarily be detectable by a leak testing technique, because as addressed above e.g. a material entrapped within the bond might not deteriorate the container's unleakyness, but may on shorter or longer terms cause tremendous deterioration of the filling product, up to making such container leaky only after some time of storage.
It is therefore an object of the present invention to provide a method for manufacturing containers of the kind as described with the help of the
FIGS. 1
to
10
, whereat an essential step of manufacturing is testing the bond area on its quality, i.e. testing “seal integrity”, so as to produce such container with high quality bond, i.e. “seal” area.
From the article “High contrast ultrasound images of defects in food package seals”, Catherine H. Frazier et al., IEEE Transactions on ultrasonics, ferroelectrics, and frequency control, Vol. 47, No. 3, May 2000, investigation of bond areas by ultrasonic response evaluation is known. It is an object of the present invention to improve such testing approach with respect to accuracy and reproducibility.
This is achieved under a first aspect of the present invention by the method of manufacturing filled containers which comprises the steps of providing at least a first and a second part of the container, providing a product within at least one of the first and the second part, assembling the first and the second parts by bonding a portion of the first part to a portion of the second part, thereby generating a bond area, scanning along the bond area with a transmitted beam of a pulse train of ultrasonic energy, sensing a reflected pulse train of ultrasonic energy from the bond area, determining time derivative of at least one of time lag and of amplitude of the sensed pulse train, generating a signal indicative of the quality of the bond along the bond area by comparing at least one of the time derivatives with a predetermined threshold value and separating containers if the indicative signal indicates a bond along said bond area which is inaccurate.
Thereby, in a most preferred embodiment the beam of pulse train is led towards and onto the bond area and the reflected pulse train is led from the bond area at least to a predominant part exclusively through liquid. Thereby, it is achieved that at least a predominant part of ultrasonic energy from a respective generator to the bond area and back to an ultrasonic energy sensor is exclusively led through the liquid.
In a further most preferred embodiment the beam of pulse train is directed in a direction towards and onto the bond area, which is different from perpendicularly thereto considered in a plane which is defined by a perpendicular line on the bond area and scanning direction of the beam along the bond area.
In further preferred embodiments the bond area to be investigated forms a loop, thereby preferably an at least substantially planar loop. Thereby, further preferably, the loop is at least substantially circular.
In a further preferred embodiment the bond area defines for at least three materials stacked one upon the other, whereby respectively two of the materials concomitantly form a material interface. Then sensing comprises sensing a reflected pulse train of ultrasonic energy from at le
Lehmann Martin
Riemer Karsten
Steck Jürgen
Antonelli Terry Stout & Kraus LLP
Lehmann Martin
Saint-Surin Jacques M.
Williams Hezron
LandOfFree
Method for manufacturing containers and apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method for manufacturing containers and apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for manufacturing containers and apparatus will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3321348