Patent Application
20240101296
This application claims the priority under 35 USC 119(a) of Italian Patent Application No. 102022000019590 filed on Sep. 23, 2022, the entirety of which is incorporated herein by reference.
The invention relates to the field of industrial thermo-sealing. Even more specifically, the invention is adapted to provide an innovative system for changing the modules of a chain conveyor in a thermo-welding machine having cells or alveolar cavities.
Packaging machines are industrial machinery developed in recent years, especially in the food packaging sector. Thanks to the spread of large-scale retail trade, the need to protect foods and increase their shelf life, understood as a conservation period, has grown, as much as possible counteracting chemical, microbiological, physical, structural and sensorial changes which are in any case inevitable over time, in agreement with Parisi's First Law of Food Degradation.
Thermo-welding machines are packaging machines for welding reeled films (polypropylene, polyester, or other plastic films) onto pre-formed plastic trays, or onto special molds to give particular shapes. The possibility of creating a vacuum inside the container and introducing inert gases makes them the most used packaging machines in food packaging. The high production capacity is also a distinctive feature of these machines which, thanks to the chain conveyor with alveoli, allow efficient management of the tray advancement.
The chain conveyor is in most cases constrained to a specific type of alveolar shape. The great variability of existing containers, for marketing reasons, makes it necessary to vary the shape in the conveyor chain lines of the thermo-welding machines. In particular in those with chain conveyor with alveoli, changing the alveolar shape is a big problem as it requires the replacement of the entire chain conveyor, unscrewing every single element to be able to replace it. This action not only requires many hours with disruption to production, but puts the operators at risk during the slat changing operations and is potentially dangerous; the risk of damage to the machine due to assembly errors is very high. To date, some solutions have been presented to avoid this problem, and in general inventions related to innovative thermo-welding systems, of which some examples follow.
One example is the object of patent application CN112810863A of C. XIAOMEI and G. MINHENG. The invention relates to the technical field of packaging machines, and describes a food packaging machine of the thermo-welding type. The machine consists of a belt conveyor, support frames, an upper roller, storage racks, a lower roller, a side plate, a transmission roller assembly, a pressure roller, a thermo-welding block and a thermo-welding assembly, the conveyor is connected to the conveyor belt, the two support frames are arranged on a frame at the upper end of the conveyor belt, the upper roller is positioned on the two support frames. The two storage racks are arranged on a frame in the lower part of the conveyor belt, and the lower roller is positioned on the two storage racks. According to the thermo-welding-type food packaging machine, when the conveyor belt and the conveyor run, the food on the conveyor can slide onto the films of the lower roller, the upper roller passes through the transmission roller assembly, and then passes through the pressure roller and the thermo-welding block, thereby the lateral edges of the two layers of film are subjected to thermo-welding in the thermo-welding block, under the operation of the pressure roller, the thermo-welded films move together with the conveyor belt, and finally, in the thermo-welding assembly, the films with the food are cut and subjected to thermo-welding.
Another example is the object of patent application WO2015086764A1 of A. ROSSINI. The invention relates to a packaging device. The packaging device comprises a welding and cutting station for welding a film on the edge of a tray and cutting said film, characterized in that it comprises a support surface comprising a plurality of housings housing a plurality of molds, said molds being of different dimensions and/or formats to accommodate trays of different dimensions and/or formats, said support surface being drivable to bring one of said molds at said welding and cutting station.
Another example is the object of patent application CN111645951A of L. CHEN and S. CHEN. The invention relates to a rapid thermo-welding machine for food packaging bags. The rapid thermo-welding device comprises a base, a support plate is fixedly mounted to the upper end of the base, symmetrical limiting blocks are fixedly connected to the front end of the support plate, a dragging disk is rotatably connected to the upper parts of the support plate limiting blocks at the front ends of the support plate, a movable plate is slidingly connected between the limiting blocks, the upper end of the movable plate is fixedly connected with a guide frame extending to the guide disk, a telescopic column is fixedly installed at the front end of the movable plate, a spring rod is fixedly connected to the lower end of the telescopic column, and symmetrical limiting rods are fixedly installed at the upper end of the base. According to the rapid thermo-welding device for food packaging bags, the guide disk rotates to guide the guide frame, so that a thermo-welding plate moves up and down. The thermo-welding plate is moved by the telescopic column, and the pressing rods fix the thermo-welding plate, so as to obtain the effects of rapid thermo-welding, correct adjustment of the thermo-welding time according to the packaging materials, and improvement of the thermo-welding quality of the packaging bag.
Another example is the object of patent application CN208976599U of Z. MIN, L. SHUWEN and L. HUA. Universal thermoforming mold sets capable of being quickly changed. The invention claims a heating module comprising an upper matrix and a lower matrix. The upper matrix and the lower matrix are fixedly connected to the outlet of the heating equipment through relative heating plates. The mold core is developed independently and is fixed in the groove of the heating module by screws, and can be replaced by unscrewing the screws and extracting it.
The inventions reported so far, purely by way of example and not exhaustively, are representative of the inventive-technological framework available to date.
The object of the present invention is to propose an innovative slat exchange system in thermo-welding machines having cells or alveolar cavities and/or similar systems, capable of solving the technical problems linked to wear of the pins, to clamping which may not be perfect (with risk of damage of the machinery or of injury for the operators), as well as long lead times with considerable production stops, typical of the existing solutions for changing slats which involve dismantling the slat itself from the chain conveyor through bolted unions.
Even more advantageously, the system lends itself to being completely automated, thus allowing the slats on the chain conveyor to be changed through a robot and significantly speeding up the format change process with all the advantages deriving therefrom.
According to the present invention, a slat exchange system in thermo-welding machines having cells or alveolar cavities and similar systems is provided which is capable of allowing the locking and unlocking of slats with alveoli along the chain conveyor, adapted to interchange the shapes in order to be able to weld different container models with the same machine.
The system comprises a slat divided into two parts, a fixed part connected to the chain conveyor with a bolted union, and a removable part on which the alveoli (or shapes) are present. The removable part can be unhooked from the fixed one through a hooking and unhooking mechanism and can be used on both of its sides, thus providing the possibility of using different alveoli on the same removable slat part.
The hooking and unhooking mechanism comprises a pin which inserts inside a symmetric groove made on the side of the removable slat part. The pin has a flat lower part and a slanting upper part, in order to allow locking the removable slat part simply by pressure, and preventing the accidental unhooking thereof. When the removable slat part is inserted by pressure, the pin snaps inside the symmetric groove, hooking it and a contrast bar, positioned on the bottom of the fixed slat part, provides support for the pressure. The pin is connected to a handle and a bar with spring. By moving the handle backwards (away from the slat) the pin then slides along the spring bar, and it is possible to remove the removable slat part. The spring bar can be replaced using magnetic, electromagnetic, hydraulic or other technology so as to have different types of machinery for automating the disassembly process.
The removable slat part is also designed so that it can house multiple modules which can be moved and recombined in order to allow for a greater number of alveoli (shapes) and to generally guarantee greater versatility.
The system comprises a check sensor which analyzes the alignment between the two parts of the slat. When these are misaligned, the thermo-welding machine is locked and a warning is sent. The sensor is also capable of measuring the distance between the edge of the fixed slat part and the end of the alveoli (or shapes). These distances are communicated to the IT system which manages the processes of the thermo-welding machine. In fact, when the thermo-welding machine is started, the IT system receives all the distances corresponding to the processes to be carried out and, if these are different from those measured by the check sensor, the IT management system locks the thermo-welding machine and sends a special warning. In fact, a difference between measurements is indicative of misalignments, or of slats mounted with the wrong set of shapes; in any case, locking the system prevents breakages and malfunctions.
The system thus designed can be easily automated by using a robot capable of unhooking the removable slat part, automatically manipulating the hooking and unhooking mechanism and positioning it in common racks or housing boxes. The robot instead hooks the removable slat part by simply pressing it against the slanting upper part of the pin which then moves back and allows the removable slat part to enter into position in the fixed part.
The release of the removable slat part, whether it is carried out manually by one or more workers, or in an automated manner, can be facilitated by using a profiled stick which is fixed in a position along the chain conveyor of the thermo-welding machine. The profiled stick automatically unlocks the hooking and unhooking mechanism when the slat slides forward; in fact, the handle slides along the profiled edge of the stick and reaches the unlocked position. Thereby the unlocked removable slat parts can be picked up by the robot or by a single operator; the length of the stick obviously determines how many slats are unlocked at the same time.
The advantages offered by the present invention are evident in the light of the description given up to now and will be even clearer thanks to the appended figures and the related detailed description.
The invention will be described hereinafter in at least one preferred embodiment by way of non-limiting example with the aid of the appended figures, in which:
The present invention will now be illustrated by way of a purely non-limiting or binding example, resorting to the figures which illustrate some embodiments with respect to the present inventive concept.
With reference to
Said slat exchange system in thermo-welding machines having cells or alveolar cavities and similar systems 100 adapted to be adopted on a thermo-welding machine having cells or alveolar cavities 10 and/or a similar system having a chain conveyor 11, a transmission chain 12, an IT management apparatus 13, comprises at least one fixed slat part 101 with a contrast bar 105, at least one movable slat part 102 with shapes 103 and a symmetric groove 104, at least one hooking and unhooking mechanism 110 with at least one pin 111, at least one handle 112 and at least one bar with spring 113, a check sensor 120, a robot 130, a profiled stick 140.
Specifically,
Finally, it is clear that modifications, additions or variations which are obvious to a person skilled in the art can be made to the invention described up to now, without thereby departing from the scope of protection provided by the appended claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 102022000019590 | Sep 2022 | IT | national |
