Apparatus for sealing an open end of a container

Technical Field The invention relates generally to the field of devices for sealing the open end of a container. More particularly, the invention relates to a device for positioning and controlling the sealing jaws during the sealing operation of the open end of the container.

Technical background [0002] Equipment for packaging liquid food in containers comprises a number of units for performing a number of stages. Briefly, such a device may include the steps of forming a tube from a web of packaging material, creating tube and transverse sleeves, sealing one end of the tube and / or cutting the tube, folding containers from the sleeves to obtain their final form, filling containers with liquid food, and finally sealing the other end of the containers. The second stage of sealing the opening, i.e. the stage of final sealing of the container, is carried out when the containers are moved horizontally. Moreover, the folding stage can be divided into a number of sub-stages. For example, during the first folding sub-step carried out in connection with the sealing step, the coffee / container hand section being sealed can be formed to have a rectangular cross-section. In the second folding sub-step, the sleeve / container may be folded such that a rectangular base is obtained, e.g., by folding the outer ends of the sealed end to the center of the sealed seal.

[0003] In the sealing stages, two sealing lips can be located on opposite sides of the sleeve. The reciprocating movement of the sealing jaws can then produce a sealing seal transversely to the longitudinal axis of the sleeve. To ensure a stable and tight seal, and to avoid unnecessary wear and tear on equipment such as sealing jaws or bearings, gears, etc., due to the movement of sealing jaws, make sure that the sealing jaws are parallel towards each other during reciprocating movement, especially when they work together.

[0004] It is known in the field of vertical flow path of containers, as in documents US 2606412, US 3245197 and US 6138442, the use of guide rods located transversely to the longitudinal course of the sealing jaws. The guide rods are driven by the same end motor, which means that the motor position error, e.g. due to mechanical wear or synchronization errors between several motors, the system and guide rods are subjected to high loads, resulting in rapid wear. The guide rods also run through the sealing jaws so that the sealing jaws must be kept relative to each other in the same plane throughout

- 2 rotation cycle. In systems where the sealing jaws are also to perform oscillating movement in the vertical plane, the load on the guide rods will be high, which will result in rapid wear of the material, and thus frequent production stoppage and replacement of parts. Due to the location of the guide rods, it will also be necessary to disassemble the entire sealing device to carry out maintenance or replacement of the guide rods. Also, due to the fact that the guide rods run through the sealing jaws, the guide rods will wear off the sealing jaws, contributing to more frequent replacement of costly, sealing jaws. Furthermore, this will affect or limit the sealing pattern of the sealing jaws, and it will not be possible to transport containers, sleeves, tubes, ribbons, etc. due to the fact that the guide rods will be in the path of movement.

[0005] Documents FR 2 893 306 A1 and FR 2 338 858 A1 disclose devices with sealing jaws that are mounted on straight guide rods and which are driven to and from a sealing engagement by eccentric shafts. Document EP 0 615 909 A1 discloses a device for sealing the top of a container, the device having sealing jaws mounted on straight guide rods and having coupling packages sealing the parts mounted below the plane of the guide rods.

[0006] Therefore, a new device for sealing containers in horizontal displacement would be advantageous, especially a device enabling parallel alignment of sealing jaws, while ensuring a durable and durable as well as a very resistant leveling system, reducing material wear, increasing efficiency, limiting the exchange of parts, reducing the wear of sealing jaws, and also reducing the restrictions imposed on possible pattern arrangements and / or sealing areas.

SUMMARY OF THE INVENTION [0007] Accordingly, the invention is preferably intended to reduce, mitigate or eliminate one or more of the above-mentioned disadvantages of the prior art, alone or in any combination, and also to solve at least the problems mentioned above, e.g. . by providing a device for sealing the open end of the package, the device comprising a first longitudinally extending, sealingly mounted jaw mounted on a bearing on a first shaft towards the rhodium eccentric, and the first shaft the rhodium eccentric rotates about a certain first axis of rotation; a second longitudinally extending, sealingly closed jaw mounted in the bearing on the second eccentric shaft, and the second eccentric shaft rotates about a second axis of rotation, the second sealingly closing jaw being parallel to the first sealingly closing jaw; at least one motor driving rotation about the first and second axis of rotation in opposite directions; the first and second sealingly closing the jaws are opposite

- relative to each other and being allowed to oscillate between the sealing position and the open position by moving towards each other and away from each other; first and second transverse guide bars, a bearing mounted between the first and second eccentric shaft; the first and second transverse guide rod cooperate with the first and second eccentric shaft via guide pins running in the guide grooves so that clearance between the first and second eccentric shaft and the first and second sealing jaws in the transverse direction is allowed .

[0008] Further advantages and preferred embodiments of the invention will become apparent from the dependent claims.

Brief Description of the Drawing [0009] These and other aspects, features and advantages that may be associated with the invention will become apparent and will be explained in the following description of embodiments of the invention, with reference to the figures of the attached drawing, in which:

Figure 1 is a perspective view of an embodiment of the invention, and Figure 2 is a top view of an embodiment of the invention.

Detailed Description of Embodiments [0010] Several embodiments of the invention will be described in more detail below with reference to the figures of the attached drawing, to enable those skilled in the art to carry out the invention. These embodiments have been presented so that this disclosure is complete and complete and also fully conveys the scope of the invention to those skilled in the art.

[0011] According to the first embodiment, illustrated in Fig. 1, a device is disclosed, the device comprising first and second longitudinally extending sealing lips 101, 102 located on opposite sides of the flow path of the packaging material or semi-manufactured container / packaging, partly folded and lifted, and transported horizontally and longitudinally through the device. For convenience, only the embodiment of the sleeve will be discussed below. The reciprocating / oscillating movement of the sealing jaws 101, 102 may then allow the formation of a sealing seal transversely to the longitudinal axis of the sleeve. The reciprocating / oscillating movement includes pushing and pulling the sealing jaws 101, 102 towards and away from each other between the sealing and the open position, respectively.

[0012] In one embodiment, the induction element can be located laterally with respect to the first sealing jaw 101, i.e. behind the sealing surface of the first sealing jaw 101. Such an induction element will heat the aluminum foil in the sleeve material and possibly the metal parts of the sealing jaws 101, 102 or their sealing surfaces, while the plastic film in the sleeve material will be melted

- 4 so that the sleeve will be tightly closed when the two sides of the sleeve are pressed together. Alternatively, the sleeve and the plastic film contained therein may be preheated before the sealing step.

[0013] The first and second servomotors 103, 104 cause reciprocating movement. To this end, the first and second servomotors 103, 104 rotate the first and second eccentric shaft 105, 106 around the first and second axis of rotation 107, 108. The first and second eccentric shafts 105, 106 can be driven / rotated in one direction when the first and second tightly closing jaws 101, 102 are pushed towards each other, and in the second direction when the first and second tightly closing jaws 101, 102 are pulled apart. When the eccentric shafts 105, 106 are driven in opposite directions, depending on whether they push the closing jaws tightly towards each other or pull them away from each other, the space needed to rotate the sealing jaws 101, 102 may decrease. Also, the sealing action may cause the packaging / container to be pushed slightly downwards, but it may cease after the sealing operation, and then the sealing sealing jaws are rotated opposite, which allows the packaging / container to maintain a favorable width also in the apical region. Due to the specific configuration of the various parts of the device, servomotors 103, 104 can be located below the table supporting the device, and then the space above the device can be kept unfilled, which reduces the risk of contamination during product filling.

[0014] The eccentric shafts 105, 106 have a greater longitudinal course than the sealing jaws 101, 102. Similarly, the tightly closing jaws 101, 102 have front and rear ends inside the longitudinal course of the eccentric shafts 105, 106. Thus, the eccentric shafts 105, 106 have frontal and rear ends located at the front and rear at the front and rear ends of the respective sealing jaws 101, 102.

[0015] The first and second guide rods 109, 110 are mounted on the first and second eccentric shafts 105, 106, respectively. The guide rods 109, 110 are located transversely and perpendicular to the longitudinal course of the first and second sealing lips 101, 102. For example, the first guide rod 109 may be attached at its proximal end to the rear end of the eccentric shaft 105, while the second guide rod 110 may be attached at its proximal end to the rear end of the eccentric shaft 106. Thus, the guide rods 109, 110 may be positioned with front and rear relative to the sealing jaws 101, 102. Further, as in the distal end, guide rods 109, 110 are provided with a guide groove 111, 112. The guide grooves 111, 112 are substantially horizontally aligned. When the guide rods 109, 110 are respectively front and back relative to the sealing jaws 101, 102, the replacement of specific parts can be done very simply. For example, it will not be necessary to disassemble the eccentric shafts, sealing jaws and guide rods to replace the guide rod or associated bushings. The guide rods are independent of the sealing jaws due to the use of separate guide pins and grooves in relation to their cooperation with the rollers

- 5 eccentric and alignment of the sealing jaws, and this eliminates the need for complex systems of induction components when used in conjunction with sealing jaws.

[0016] In one embodiment, the guide rods 109, 110 are arched upwards such that the sleeves, semi-manufactured containers and / or containers are allowed to pass in a horizontal longitudinal direction.

[0017] Each guide groove 111, 112 closes and cooperates with the guide pin 113, 114 located on the eccentric shaft 105, 106. The guide pin 113 can therefore be located at the front end of the eccentric shaft 105, while the guide pin 114 can be located further the end of the eccentric shaft 106. In this way, clearance is allowed between the first and second eccentric shaft 105, 106 and the first and second sealing jaws 101, 102, in the transverse direction, because the guide pin 113, 114 will run transversely in the guide groove during rotation eccentric shafts 105, 106. Also, due to the fact that the guide pin can rotate inside the guide groove, it will be possible to have small backlash vertically compensated without unnecessary load on the system and its parts, while maintaining the alignment of the sealing jaws 101, 102. Thus, the eccentric shafts 105, 106 can rotate about the first and second axis of rotation 107, 108, respectively, causing the sealing jaws to move reciprocally / oscillating between the sealing and open position. When each eccentric shaft 105, 106 is provided with a guide rod 109, 110, extending further toward the other eccentric shaft at opposite ends of the eccentric shafts, the cooperation between the guide grooves and the guide pins will allow mutual stabilization of the eccentric shafts 105, 106 so that parallel position of the sealing jaws 101, 102, regardless of the eccentric movement. Therefore, this system also allows asymmetric displacement of eccentric axes. This means that a failure in the form of one servo motor position error, e.g. as a result of mechanical wear, or also synchronization errors between servomotors can be compensated by cooperation between eccentric shafts 105, 106, which eliminates the problems associated with controlling the alignment of a single motor.

[0018] As illustrated in Fig. 2, eccentric units 115, 116 can be located at the ends of the shafts associated with the first and second axis of rotation 107, 108 respectively, forming the eccentric shafts 105, 106 respectively. When the eccentric shafts 105, 106 become formed by placing eccentric units 115, 116 at the shaft ends associated with the first and second axis of rotation, replacement of bearings or parts will be facilitated. The first and second tightly closing jaws 101, 102 are located on bearings, such as on a bearing mounted on the first and second eccentric shaft 105, 106 respectively. The first and second tightly closing jaws 101, 102 are aligned horizontally and parallel to each other so that the interaction surface on the first sealing jaw 101 faces the interaction surface on the second sealing jaw 102. The first

The sealing jaw 101 includes a heating element, such as an induction element, for heating and thus for sealing the container by welding the sleeve.

[0019] The bearing may be positioned, as secured, between the guide pin 113, 114 and the guide groove 111, 112. The bearing may, for example, be a polymer box made of a very strong and low-friction polymer. A suitable polymer for this purpose can be selected from the group consisting of polytetrafluoroethylene (PTFE), polyether ether ketone (PEEK), polyimide (PI), polyether sulfone (PES), polyamide (PA) and polyoxymethylene (POM) or any combination thereof. When the bearing is a polymer box of this type, an improved, long-lasting strength connection is obtained between the guide groove and the guide pin, because the plasticity of the polymer material will compensate for material wear. The large contact surface between the polymer box and the guide groove contributes to even better compensation of material wear. Thus, a substantially rectangular or square cross-section in a non-transverse plane contributes to improved wear compensation. Due to the location of guide pins 113, 114 and guide grooves 111, 112 laterally to the sealing jaws 101, 102, looseness in the event of control or positioning errors on the eccentric axes will only be partially transferred to the sealing jaws 101, 102, depending on the relationship between the distance respectively from the guide pins 113, 114 to the sealing jaws 101, 102 and the distance respectively between the sealing jaws 101, 102 and axes of rotation 107, 108. In this way such clearances can be reduced by approximately 50 to 90% under normal conditions, depending on the compound.

[0020] The controller may be adapted to send control signals to the first and second servomotor 103, 104. The control signals allow the lateral movement between the first sealing jaw and the second sealing jaw to be synchronized. When the rotation of the first and second sealing jaws 101, 102 are synchronized, the first and second sealing the jaws 101, 102 may cooperate with each rotation of the first and second eccentric shaft about the first axis of rotation and the second axis of rotation, respectively. The first and second servomotors 103, 104 will rotate the first and second eccentric shaft 105, 106 in opposite directions so that the sealing jaws 101, 102 will cooperate as they move downward. When the sealing jaws 101, 102 begin to cooperate during downward movement, the sealing action will simultaneously push the now sealed container down onto the transport surface, moving the container during the sealing stage. This will initiate folding of the container along pre-printed folding lines.

[0021] In one embodiment (not shown), the first and second guide rods may also be mounted in the bearing on the first or second eccentric shaft. The guide rods are still located transversely and perpendicular to the longitudinal course of the first and second sealing jaws. The first and second guide rods can then be attached at their proximal ends, respectively

- 7 to the rear and front ends of the eccentric shafts. Thus, the guide rods can be positioned at the front or rear respectively with respect to the sealing jaws. Further, as at the distal end, the guide rods are each provided with one guide groove. The guide grooves are aligned horizontally. Also in this embodiment, each guide groove will close and cooperate with guide pins located on the second eccentric shaft at its rear and front end.

[0022] According to one embodiment, the device of the above is included in a packaging machine for producing filled containers from blanks or sleeves (not shown). For the sake of simplicity, only an empty embodiment will be mentioned below. The packaging machine may include a transporter for transporting blanks and semi-manufactured containers between the various stages and units of the packaging machine. In one embodiment, the packaging machine includes a loading unit where the blanks are loaded before being processed into a filled container. The folding unit and the bottom sealing unit can be located further down the production line after the loading unit. After the loading unit, folding unit and bottom sealing unit, the semi-manufactured container is transported horizontally by the conveyor in an upright position, i.e. with the open end turned upwards, with the now sealed and folded bottom end standing on the conveyor. The semi-manufactured containers are then transferred by a conveyor to a filling unit, where the containers are filled with the target product. Further in the production line behind the filling unit is located the upper sealing device according to the embodiments disclosed in Figures 1 and 2. This sealing device closes the upper end of the semi-manufactured containers tightly. Due to the fact that the guide rods 109, 110 are separate from the sealing jaws 101, 102 and possibly arched upwards, the semi-manufactured containers will have a free, longitudinal and horizontal transport path, which eliminates the need for complex lifting or lowering operations sealing the jaws or semi-manufactured container. Also due to the fact that servomotors can be located below the conveyor, as well as the space above the upper, sealing device can be kept open, the risk of contamination of the sealing device with products such as food products is minimized, and thus the need for cleaning is reduced . It will also be possible to seal more than one container during each rotation of the eccentric shafts 105, 106 by indexing the conveyor. After carrying out the sealing operation of the top, the produced container can optionally be transported by a conveyor to an end unit performing the final assembly of the top structure of the container. Then the packaging leaves the packaging machine.

[0023] Although the invention has been described above with reference to specific embodiments, it is not intended to be limited to the specific form given herein. Instead, the invention is limited only by the attached

- 8 claims, wherein other embodiments than those mentioned above are also possible within the scope of the appended claims.

[0024] In the claims, the term "comprises / containing cy (includes / includes cy)" does not exclude the presence of other elements or steps. Moreover, although they are listed individually, a greater number of means, elements or steps of the method can be implemented, e.g. by a single unit or processor. In addition, although individual features may be included in the various claims, they may optionally be advantageously combined in combinations, and inclusion in the various claims does not render any combination of features inappropriate and / or advantageous. In addition, the use of the singular does not exclude plurality. The terms singular, "first", "second" etc. do not exclude plurality. The reference numbers in the claims are used only as an explanatory example and should not be construed as limiting the scope of the claims in any way.

Prepared and verified

Grażyna Palka Patent Attorney