Manufacturing container or tube from paper; or other manufacturi – Container making – Pliable container
Reexamination Certificate
1999-05-24
2001-04-03
Gerrity, Stephen F. (Department: 3721)
Manufacturing container or tube from paper; or other manufacturi
Container making
Pliable container
C493S202000, C493S203000, C493S197000, C493S207000
Reexamination Certificate
active
06210308
ABSTRACT:
TECHNICAL FIELD
The present invention relates to a sealing apparatus for sealing foil material, the apparatus comprising a foil conveying means and a sealing means including a sealing head, and to a method for sealing foil material.
BACKGROUND OF THE INVENTION
In a sealing apparatus for sealing foil material, two or more foils are fed to a sealing means and are there sealed together with the aid of a sealing head which is lowered onto the joined foils and transmits heat to the foils at the desired places. Insofar as sealing or sealing means is referred in the present text, this includes a hot bonding process in which an adhesive material is applied between the foils to join the foil materials by heat.
Such a sealing process is e.g. used in the production of foil bags, e.g. foil bags for beverages. Two foil materials are laid one upon the other to form the side foils of the foil bag. A bottom foil is possibly interposed in an edge portion. The foils are sealed together at two directly superimposed edges of the side foil material and at the third edge where the bottom foil is optionally positioned. The fourth edge of the respective foil materials is closed by sealing after the foil bag has been filled. An example of such a foil bag is e.g. shown in
FIG. 3
where the weld seams
33
are formed in the first-described process and the weld seam
34
is formed after the foil bag has been filled.
In an automated production plant, foil webs are supplied for sealing purposes, with the webs being cut after the sealing process so as to form individual units. The foil webs are placed one upon the other and guided below the sealing head. The head is lowered. In doing so, it must cover a lowering distance of a few centimeters. After having been pressed onto the foil materials, the sealing head is again lifted and the foil webs are further transported by a distance corresponding to one foil bag before the sealing head is again lowered onto the foil material that has been transported further away. To achieve a high throughput, the sealing head is kept at a constantly high temperature to make time-consuming heating and cooling processes superfluous. Therefore, it is necessary that in the operative states in which no sealing operation takes place the sealing head should be so remote from the foil material that the foil material is not overheated or scorched. Such a distance is e.g. required in cases where the entire sealing apparatus has been stopped to eliminate a malfunction.
However, in an automated manufacturing plant, the lifting and lowering movement of the sealing head, which amounts to a few centimeters, takes an undesired long period of time at the throughput rates which are nowadays possible.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a sealing apparatus and a method for sealing foil material which make it possible to lift and lower the sealing head rapidly, whereby it is ensured in every operative state that the foil material cannot be scorched or damaged.
The sealing apparatus according to an embodiment of the invention can assume at least three operative positions. The first operative position is the sealing position for performing the foil sealing operation. In this operative state the sealing head is directly positioned on the foil materials to be sealed, thereby heating and sealing or hot bonding the foil materials in those areas on which the heated surface of the sealing head is positioned. The second operative state is an intermediate position in which the sealing head has a first predetermined distance from the sealing position. The sealing head is positioned in this intermediate position while the foil material is further moved by one unit to be sealed. The third operative position is a rest or inoperative position in which the sealing head has a second predetermined distance from the sealing position that is greater than the first distance. The sealing head is in this inoperative position when the sealing apparatus does not convey the foil material at a sufficient speed to prevent overheating or scorching.
Hence, the sealing apparatus of the invention permits a short lifting and lowering operation between the sealing position and the intermediate position so that such a movement of the sealing head will not lead to any loss of time during normal operation even if the entire sealing apparatus is operated at a high speed. In case of a malfunction or at a low speed of the entire system the sealing head assumes an inoperative position which has a greater distance from the foil material so that the foil material is not damaged by the hot sealing head.
The distance of the inoperative position from the sealing position can be chosen such that damage to, e.g. scorching of, the foil material by the heat of the sealing head is considerably reduced. In a particularly advantageous development the distance between the inoperative position and the sealing position is however chosen such that the foil material can definitely not be damaged by the heat of the sealing head. It is thereby ensured that independently of the duration of the interruption or slowing down of the operation of the sealing apparatus the foil material cannot be damaged.
A particularly advantageous embodiment comprises a heat shield which in the inoperative position is moved between the hot sealing head and the foil material. Especially with particularly temperature-sensitive foil materials, such an additional shield guarantees that the foil material is not damaged by the heat of the sealing head. Such a heat shield may e.g. comprise a pivotable shield plate.
Advantageous values for the distance of the inoperative position from the sealing position are within the range of a few centimeters. This distance substantially depends on the type of foil material used, the sealing temperature and the geometry of the sealing tool used. Advantageously, a distance of a few millimeters is chosen for the distance of the sealing position from the intermediate position. Such a small distance guarantees a high throughput speed due to the short lifting path.
The sealing head can be moved in various ways, e.g. by an electromagnetic device or a corresponding spindle gear. The sealing head can easily be moved between the intermediate position and the sealing position with the help of a first pneumatic means. On account of the small distance which must be overcome, the pneumatic means only needs a very small amount of compressed air. A second pneumatic means can be used for moving the sealing head together with the first pneumatic means into the inoperative position.
The movement of the sealing head and the associated drive can e.g. be initiated mechanically. A reliable implementation is achieved with a control unit with the aid of which the conveying means is activated for further transporting the foil material while the sealing head is in the intermediate position.
REFERENCES:
patent: 2660219 (1953-11-01), Haas et al.
patent: 3748205 (1973-07-01), Adams
patent: 3896708 (1975-07-01), De Vries
patent: 4077308 (1978-03-01), Scully
patent: 4185443 (1980-01-01), Budzyn
patent: 4622798 (1986-11-01), Oki
patent: 4662978 (1987-05-01), Oki
patent: 4994137 (1991-02-01), Yanai
patent: 5019027 (1991-05-01), Boeckmann et al.
patent: 5080747 (1992-01-01), Veix
patent: 5195435 (1993-03-01), Morrone et al.
patent: 5662575 (1997-09-01), Saito et al.
patent: 5715656 (1998-02-01), Pearce
patent: 368973 (1982-11-01), None
patent: 25 34 306 (1974-12-01), None
patent: 2534306A1 (1976-07-01), None
patent: 27 00 971 (1976-12-01), None
patent: 2700971A1 (1977-08-01), None
patent: 368973 (1980-08-01), None
patent: 34 25 430 (1986-01-01), None
patent: 3425430A1 (1986-01-01), None
patent: 3727339A1 (1989-03-01), None
patent: 37 27 399 (1989-03-01), None
patent: 195 02 830 (1996-08-01), None
patent: 19502830A1 (1996-08-01), None
patent: 29521183U1 (1996-11-01), None
patent: 295 21 183 (1996-11-01), None
patent: 0335270A1 (1989-10-01), None
patent: WO91/18797 (1991-12-01), None
patent: WO 91/18797 (1991-12-01), None
Kraft Eberhard
Wild Hans-Peter
Gerrity Stephen F.
Indag GmbH & Co.
Seed IP Law Group PLLC
Tawfik Sam
LandOfFree
Apparatus and method for sealing foil material does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Apparatus and method for sealing foil material, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus and method for sealing foil material will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2445677