Sealing strip for controlling the introducing of gas into packages

p0001The invention relates to a packaging machine according to the preamble of claim 1.

p0002Packaging machines for packaging of packaged goods in packages are known in various designs. In the field of food packaging machines are commonly used, in which the atmospheric air is sucked out of the filled package, and then one or more gases before sealing are supplied to the packaging. This evacuation and subsequent gas supply is, inter alia, for the durability of the packaged products is important.

p0003In conventional machines, the packages are evacuated in a vacuum chamber. The gas supply is via gas pipes, which are laid in the area of ​​packaging to be fumigated. Since the packages are not sealed during fumigation, the gas supplied to the same can away, as before, the residual atmosphere was evacuated, enter the vacuum chamber or the suction system of the machine. A controlled dose fumigation of packaging is therefore not possible.

p0004The invention has therefore the object to provide a packaging machine in which a controlled supply of gas is possible in the packaging.

p0005This object is achieved on the basis of a packaging machine of the type described by the characterizing features of claim 1.

p0006By the Unteransprüchen said measures are vorteilhafte versions and Weiterbildungen the invention possible.

p0007Accordingly, the invention is distinguished in that means are provided for sealing the packaging with respect to the suction means prior to the subsequent gas supply.

p0008In this way, a passage of the supplied gas is prevented from the packaging into the flow path of the machine used for suction. The gas supplied can thus controls the packaging is introduced. It is better overall dosage of the gas to be supplied and thus a better match to the pre-packaged in the packaging packaged goods possible.

p0009In a packaging machine according to the invention also a plurality of contiguous packaging may be evacuated and gassed at once. Here, it is not necessary that each individual package has a suction opening and a gas inlet port is assigned. Several contiguous containers may be fumigated also via one or several common evacuated suction ports and one or more common gas supply lines prior to sealing the contrary.

p0010The invention is advantageously used for packaging, which are made of at least two films, for example an upper and a lower film. Such packaging machines are known under the terms thermoforming or roll machine and a tray sealing machine (so-called "tray sealer").

p0011In the first type of machines multiple contiguous packaging trays are formed from a lower foil, then filled with goods and sealed with a top film. In a sealing station to extract, gassing and sealing the packaging is made conventionally in a single operation. Only after sealing the package they are cut in a downstream cutting unit in individual packages.

p0012In the so-called "tray sealers" prefabricated individual cups are filled with goods and then sealed in a sealing station with a top film, a suction and gassing can occur before sealing again. The packaging tray is also prefabricated in general of a film.

p0013Individual shells have from a circumferential edge web, while the related packaging may also include intermediate webs between the individual packages from a deep drawing or rolling machine next to the outside edge webs. On these lands, the top film is fixed in sealing the packaging, for example welded.

p0014Prior to the aspiration of the atmospheric air from the packaging they are preferably placed in a vacuum chamber. This is closed by in known embodiments that two parts of the chamber joined together, for example, a base is raised to a shell. The sidebars of packages are between the upper and lower part of the vacuum chamber. When compressing these two components thus upper and lower films are compressed, so that at least with respect to the transverse direction to the direction of a suitably tight seal can be done.

p0015can be both sucked and gas can be supplied between the upper and lower films. Depending on the embodiment of the packaging machine different approaches are possible. When using such a narrow top film, that it is not laterally compressible between the parts of the vacuum chamber with the lower film, the packaging may be evacuated by a vacuum in the vacuum chamber, the flowing out of the packaging air emerges at the edge between the lower film and the upper film. In a broader top web it can be completely compressed upon closure of the vacuum chamber between the parts with the lower film. In this case, the air can be sucked through one or more openings in one or both films, for example in an edge web of the base film in the packaging. These openings are preferably in the edge region of the packaging or the assembly of packaging in the case of a continuous range of packaging.

p0016In such a top and bottom sheet existing packaging can accordingly characterized close that press members are used which compress the two films of the flow path for the air to be sucked off from the packaging. An escape of gas below the edge of the upper foil or by any suction openings in one or both films, for example the lower film is thereby prevented, as these suction openings are the same as the entire edge area can be closed by pressing together the films. It is irrelevant whether such an opening is closed by the other film or directly by the pressing member.

p0017A pressing member for sealing the edge portion of the packaging may be (relative to the direction of advance of the packages in the packaging machine) are realized by a transverse sealing strip in the region of the transverse webs, which is advantageously designed as a functional unit with a wall part of the vacuum chamber.

p0018In the longitudinal direction relative to the feeding direction of the packages are an usually or more gas supply lines. These are preferably so arranged that they open out between the films, for example between an upper and a lower foil. Since these gas supply lines are in the interior of the vacuum chamber is in vacuum chamber closed without inventive sealant possibility that supplied in the packaging gas can get into the vacuum chamber and thus in the suction system of the machine.

p0019To avoid this, as already mentioned several times, a sealing of the interior of the package sought. In the longitudinal direction, this is now preferably carried out in a preferred embodiment of the invention with an additional pressing member, that the films, for example, compresses the upper and lower films. For this purpose, one or more sealing strips may be used for example, extending in the longitudinal direction of the packaging or of assemblies or groups of packaging.

p0020To operate this press members the use of a lifting unit is provided, by means of which the longitudinal and / or transverse sealing strips are raised and lowered.

p0021When using gas supply lines which are arranged in the intermediate space between the sheets, the peripheral sealing means, in particular in the form of sealing strips are preferably so formed as to surround the gas supply lines form fit. The films or of films, for example, the top film, it nestles between the sealing strips and the gas line to the shape of the gas line. For this purpose, the film is formed advantageously elastic.

p0022By means of such a shaped sealing elements, a sufficient sealing of the interior of the packaging is achieved to a substantially more controlled make the gas supply than was previously the case.

p0023In a particular embodiment of the invention a deformable material, for example an elastomer is used for a sealing strip at least in the region of the gas supply lines. Thus sealing strips can, for example, completely in the region with which to press the sheets together, made of an elastomer. This material deforms when pressed such it is a form-fitting snugly to the gas supply lines, and these will be included in a sense in the sealing strip.

p0024In packaging machines according to the invention the sealing of the packaging can be carried out in a conventional manner by connecting upper and lower films, for example by welding. For this purpose, a sealing tool, such as a sealing plate or the like within the sealing strips is preferably arranged. This sealing tool is then in a position to connect within the sealing strips on the edge webs, the upper and lower films to weld, for example. In individual packages while the circumferential edge is welded, the inside directly adjoins the sealing strip, squeeze the top and bottom sheet. In an arrangement of a plurality of contiguous packaging such as from a deep drawing or rolling machine and the central intermediate and longitudinal webs are sealed in a conventional manner. The to be sealed in the region of the sealing strips the longitudinal and / or transverse webs, for example. The edge-side longitudinal webs are sealed in the interior directly adjoining the corresponding sealing strip area as in the case of individual packaging.

p0025The operation of such a packaging machine may run as follows. A controller for the cyclical feeding of individual packages or an arrangement of several, related packaging causes a corresponding transport unit for feeding the filled packages in machine cycle in the lower part of the sealing station. To this end, the bottom part is lowered in the sealing station. This lower part is then lifted so that the vacuum chamber is closed for sucking the atmospheric air. Now, the atmospheric air contained in the packaging can be sucked together with the other, located in the vacuum chamber via an air suction pump. The air can escape this, in the transverse direction between the upper and lower film of the packages, where the upper film is correspondingly narrow. With wider top film which also included on the long side extends to the direction of the machine in the area between the upper and lower part of the vacuum chamber and is thus compressed in this area with the lower film, suction as can conventionally in the lower film and a subsequent assembly of suction lines are used to aspirate the residual atmosphere in the packaging.

p0026Subsequently, provided for sealing in the longitudinal direction and / or transverse sealing strips are laterally lowered .. This provides a seal between the upper and lower film is effected in this area. while any protruding between the sheets gas supply lines are received positively Particularly when using elastomers.

p0027Now an appropriately provided gas or a gas mixture can be supplied. This can be accomplished with the aid of the existing vacuum and or with the aid of an external overpressure. Since the interior of the packaging are substantially sealed to the outside, there is at the time of gas supply is no connection between the interior of the packaging and the suction system. Thus, inter alia, accurate metering of the supplied gas is possible.

p0028An embodiment of the invention is illustrated in the drawing and is explained in detail below with reference to FIGS.

p0029show in detail<dl id="dl0001"><dt>Fig. 1</dt><dd>shows a schematic longitudinal section through a sealing station of a first embodiment of the invention,</dd><dt>FIG. 2</dt><dd>a schematic cross section through a Sigel station according to FIG. 1,</dd><dt>FIG. 3.</dt><dd>an enlargement of a cross section of a sealing station of Fig. 1 and Fig. 2 with a raised sealing strip,</dd><dt>Fig. 4</dt><dd>a representation according to FIG. 3 with a lowered sealing strip,</dd><dt>Fig. 5</dt><dd>another enlarged detail from the cross section shown in FIGS. 1 and 2 in the field of gas supply,</dd><dt>Fig. 6</dt><dd>shows a schematic longitudinal section through a further embodiment of the invention, </dd><dt>Fig. 7</dt><dd>a schematic cross section through a sealing station according to FIG. 6,</dd><dt>Fig. 8</dt><dd>an enlargement of a cross section of FIG. 7 with a raised sealing strip,</dd><dt>Fig. 9</dt><dd>an enlarged detail, as shown in FIG. 8 with a lowered sealing strip and</dd><dt>Fig. 10</dt><dd>an enlarged detail of a schematic longitudinal section of FIG. 6.</dd></dl>

p0030The sealing station 1 of FIG. 1 shows a vacuum chamber 2, which is formed of a box-shaped upper part 3 and a likewise box-shaped lower part 4. In the present embodiment, a seal 5 is provided to seal the vacuum chamber 2 in the closed position at the upper edge of the lower portion of the third

p0031One of a. Lower film 6 formed shell is inserted into the lower part 4 of the vacuum chamber. 2 The edge web 7 of the lower sheet extends between the upper part 3 and lower part 4 via the vacuum chamber 2 addition, since the lower film is continuously withdrawn from a supply roll in the case of deep drawing or rolling machine. The film, with the resulting formed shells thus extends longitudinally in a row from the supply roll to a not shown cutting station behind the sealing station through the entire machine.

p0032A provided as lid top film 8 closes the top of the lower film 6 and also extends with its edge 9 in the area of ​​the edge web 7, as it will also be deducted at a time from a supply roll.

p0033A relative longitudinally L to the direction of the films in the packaging machine extending sealing strip 10 is arranged in the vacuum chamber 2 and provided with a lower cut-11th Suction pipes 12 as well as gas supply lines 13 are indicated in Fig. 1 in order to illustrate their position in the longitudinal direction 11. In fact, there are the lines 12, 13 in respect to the representation in Figure 1, the rear longitudinal wall of the vacuum chamber 2 and are thus in a section according to FIG. 1 ansich not visible.

p0034Is recognizable by this indication of the position of the lines 12, 13 in FIG. 1 however, that the suction pipes 12 are arranged in longitudinal direction underneath the sealing strip 10, while the gas supply lines 13 are arranged in the region of the recess 11.

p0035In the schematic cross sectional view of FIG. 2 is represented by a gas supply line 13 on the right side is a section. In this representation it can be seen that the gas supply line 13 is arranged in a side wall 14 of the lower part 4th Shows an enlarged detail of the central area, in accordance with the invention, the sealing strip 10 is arranged, is shown in FIG. 4 and discussed later.

p0036On the left is shown a section through a suction line 12 in FIG. 2. Accordingly, the sealing strip is 10 cut here a receptacle outside of the recess 11 via a suction line 12 range. Furthermore, in FIG. 2 is still a sealing plate 15 recognizable, which serves as the sealing tool for sealing the package formed from the lower film 6 and the upper film 8 16.

p0037In Fig. 3 is the sealing strip 10 comprising enlarged section of FIG. 2. Deviating from FIG. 2 allerdingsdie sealing strip 10 is shown in its raised position, in which the package 16 is evacuated. As 3 can easily be seen in Fig., The lower film 6 and the upper film 8 are peripherally compressed by the lower part 4 and the upper part 3 of the vacuum chamber 2. This packing 16 is sealed edges. Through the suction port 12a of the suction pipe 12 S air can now with a suitable vacuum, are sucked out of the package 16, for example, by a suction pump in the suction direction. The flow path between the lower film 6 and the upper film 8 to the suction line 12 is open in this position.

p0038In FIG. 4, the same section is shown wherein now the sealing strip 10, which is movable in the direction of the double arrow H, is lowered. Thus, the top film 8 is pressed in the area of ​​the suction port 12a of the suction pipe 12 to the lower film 6, whereby the suction opening 12a is closed. The position shown in Fig. 4 the sealing strip 10 is adjusted when a gas or gas mixture to be fed into the packaging sixteenth

p0039In FIG. 5, which shows a cross section through a sectional plane in the region of a gas supply line 13, is also seen that the sealing strip 10 is in the lowered position. However, a gas supply between the lower film 6 and the upper film 8 is due to the recess 11 in the area of ​​the gas supply line 13 possible. For gas supply one or more inlet openings 13a are provided for this purpose in the edge web 7th A feed end gas can be guided into this position, as indicated by the arrows Z through the gas supply pipe 13 into the packaging sixteenth Since in the same position of the sealing strip 10, the suction ports 12a are closed, is at this moment no connection between the interior of the package 16 and the suction or vacuum system of the machine. Thus, a controlled gas supply is possible to the interior of the package sixteenth

p0040Fig. 6 shows another variant of the invention, which is for example used when the top film 8 is formed narrower than the vacuum chamber 2. This is for example seen in the cross-sectional view of FIG. 7. Here visible ends the top film 8 at its edges 17 in the interior of the vacuum chamber 2 below the now somewhat modified sealing strip 18. In this embodiment, the suction and the supply of gas takes place in the manner described below.

p0041As is already shown in FIG. 6, seen lateral protruding between upper film and lower film 8 6 gas supply pipes 19 are provided, which open out below the sealing strip 18 into the interior of the packaging sixteenth The sealing strip 18 is in this case provided at its lower edge with an elastic material 20, for example an elastomer. As is already shown in FIG. 6 seen encloses said elastomer 20 in the lowered position of the sealing strip 18, the gas supply lines 19.

p0042In Fig. 7 can be seen how the gas supply lines 19 protrude below the edge of the sealing strip 18 into the interior of the packaging sixteenth

p0043The enlarged detail of FIG. 8 shows the sealing strip 18 in the raised position, which is used during the evacuation process. The air between the upper and lower film 6, 8 can escape and enter laterally next to the gas supply line 19 into the upper portion 21 of the vacuum chamber 2 (see arrow S). also located in the package 16, air is thus sucked by evacuating the vacuum chamber second

p0044Fig. 9 shows the time allotted for the gas supply lower position of the movable in the direction of the double arrow H sealing strip 18. It can be seen that the top film 8 is pressed from above on this in the region of the gas supply line 19. For this purpose offset in the longitudinal direction pushes the edge attached elastomer 20, the top film 8, however, directly to the lower film 6 as shown in FIG. 10 in the region of the gas supply line 19 is. The elastomer 20 adapts form-locking to the gas supply line 19, so that a continuous pressure on the top film 8 is exerted, and this thus, the package can 16 to seal the edge side in interaction with the lower film 6th Through the gas supply pipe 19, the interior of the package 16 can be filled with a desired gas or gas mixture in this position without any gas flow into the region of the suction system, and in particular the vacuum chamber 2, takes place. Also in this embodiment, an improve control of gas supply or gas metering is possible.

p0045As can be seen in both illustrated embodiments, the packaging can 16 by the sealing plate 15 in the edge region of the package 16 within the sealing strips 10, 18 after filling are sealed tightly with the desired gas.

p0046The illustrated embodiments are only shown for simplicity with a packaging sixteenth However, the invention can be readily applied also in sealing stations in which multiple packages 16 are arranged in several rows and / or columns. If these packages are 16 contiguous made of a lower film 6 and contiguous sealed with a top film 8, the same procedure can be selected. Also in this case, the suction through suction holes and edge-side edge-side gas supply lines can take place.

p0047Moreover, in such an embodiment, additionally one or more sealing strips 10, 18 are provided in the region of the intermediate webs between individual packages, although this is not fundamentally required. Essential in the invention is the sealing of the interior of the package 16 relative to the suction system of the machine.

p0048The invention is also not limited to the arrangement of upper and lower parts 3, 4 of the sealing station 1 shown. It is readily apparent that the reverse arrangement of the gas supply is also realized from above, through corresponding openings in the top film and the advantages of the present invention-provides. Likewise, it is irrelevant for the invention whether the top or bottom part of the vacuum chamber are movable. In principle, the method can be realized according to the invention with a differently configured suction arrangement, if only there is provided a separation between the suction system and the interior of the packaging.

LIST OF REFERENCE NUMBERS

p0049<dl id="dl0002" compact="compact"><dt>1</dt><dd>sealing station</dd><dt>2</dt><dd>Vacuum chamber</dd><dt>3</dt><dd>top</dd><dt>4</dt><dd>lower part</dd><dt>5</dt><dd>poetry</dd><dt>6</dt><dd>lower film</dd><dt>7</dt><dd>edge web</dd><dt>8th</dt><dd>top film</dd><dt>9</dt><dd>edge</dd><dt>10</dt><dd>sealing strip</dd><dt>11</dt><dd>recess</dd><dt>12</dt><dd>suction</dd><dt>12a</dt><dd>suction port</dd><dt>13</dt><dd>Gas supply line</dd><dt>13a</dt><dd>inlet port</dd><dt>14</dt><dd>Side wall</dd><dt>15</dt><dd>seal plate</dd><dt>16</dt><dd>packaging</dd><dt>17</dt><dd>edge</dd><dt>18</dt><dd>sealing strip</dd><dt>19</dt><dd>Gas supply line</dd><dt>20</dt><dd>elastomer</dd></dl>