Packaging device

Abstract

The invention relates to a device (10) for packaging food portions (12) comprising a packaging device (20), a feeding device (22) for feeding the food portions (12) to the packaging device (20) at equal spatial intervals, wherein the feeding device (22) has a circumferential carrier (24) and carriers (26) for the food portions (12) arranged at equal intervals on the carrier (24) and projecting from the carrier (24), and a conveying device (30) for transporting the food portions (12) to the feeding device (22) in a conveying direction (32).According to the invention, the conveying device (30) comprises several conveyor belts (34) arranged successively in the conveying direction (32), each driven by a drive motor (36), a conveyor belt control unit and sensors (42) for detecting the food portions (12), wherein the conveyor belt control unit is configured to control the drive motors (36) of the conveyor belts (34) depending on data obtained from the sensors (42) in such a way that the food portions (12) are brought to spatial distances from each other.

Description

[0001] The invention relates to a device for packaging food portions according to the preamble of claim 1.

[0002] Prior packaging devices of the type mentioned above have a packaging unit that packages the food portions, for example, by sealing them in a plastic film. The food portions are fed to the packaging unit by means of a feeding device, which has a circulating carrier, such as a chain or belt, and protruding carriers for the food portions arranged at equal intervals on the carrier. Each carrier picks up one food portion, so that the food portions are fed to the packaging unit at predetermined and constant intervals. A conveying device is located upstream of the feeding device, which transports the food portions to the feeding device, and a transport device is located upstream of the conveying device to transport the food portions to the conveying device.In previously known packaging devices, where the conveying system usually consists of a conveyor belt, the food portions can overlap before reaching the feeding device, which is very disadvantageous for some types of products. For example, if the food portions are ice cream portions, they can thaw and merge together, resulting in an unsightly appearance after being separated again in the feeding device. Ready-made pizzas, for instance, can overlap and be pushed on top of each other, making it impossible to package them individually automatically.

[0003] It is therefore an object of the invention to further develop a device of the type mentioned at the outset in such a way that damage to the food portions during transport to the packaging facility is avoided or at least reduced.

[0004] This problem is solved according to the invention by a device having the features of claim 1. Advantageous embodiments of the invention are the subject of the dependent claims.

[0005] The invention is based on the idea of ​​ensuring, through targeted control of the successive conveyor belts, that the food portions in the conveying device are placed at spatial distances from one another. These distances can, for example, always be the same and correspond to the distance between two successive carriers of the feeding device. However, the latter is not strictly necessary. The important thing is simply that the food portions are placed at spatial distances from one another, which can be predetermined, but also random and irregular. The conveyor belt control unit is expediently designed to transfer the food portions individually between two carriers to the feeding device. The last conveyor belt in the conveying direction can be stopped until a carrier reaches the transfer point.The arrival of the conveyor can trigger a signal that is transmitted to the conveyor belt control unit, which then initiates the transfer of the food portion to the feeding device. The conveyor belt control unit also controls the conveying device in such a way that food portions do not collide but are always kept spaced apart, thus preventing back pressure. For this purpose, sensors are provided to detect the food portions, and their data is transmitted to a conveyor belt control unit, which controls the drive motors of the conveyor belts based on the data received from the sensors. Furthermore, this facilitates empty-pack operation of the device, ensuring that no empty packages are produced even if there are not enough food portions to be packaged.It is preferred that each conveyor belt is assigned at least one sensor for detecting the food portions, the sensors being advantageously light barriers.

[0006] The conveyor belt control unit is advantageously configured to control the drive motor of the first conveyor belt (in the direction of conveying) so that the first conveyor belt moves at a constant speed. This speed is preferably at least as high as the speeds of the other conveyor belts. In this way, food portions arriving at the conveyor, usually delivered by an upstream transport system, are immediately moved on at the highest possible speed, thus creating spaces between the food portions. At least one of the sensors is advantageously designed to detect the food portions along their entire length. This can be, in particular, the sensor of the second conveyor belt following the first.This then not only detects the front edge of the food portion, so that the arrival of the food portion is detected, but it also detects the rear edge of the food portion, so that it not only detects when a food portion reaches the sensor area, but also when the food portion leaves the sensor area again.

[0007] According to an advantageous embodiment of the invention, which may also constitute an independent invention, the packaging device comprises a shaft rotatably mounted about its longitudinal axis for mounting a roll of wound plastic film, an unwinding unit for applying tension and unwinding the plastic film from the roll, a packaging unit for wrapping the food portions in the plastic film, a motor for driving the shaft, and a film control unit for determining the tensile force acting on the plastic film and for controlling the motor depending on the determined tensile force. The packaging unit can, for example, wrap the plastic film around the food portion and cut film sections to length, thereby preferably sealing the food portions airtight in the plastic film, for example, by welding. Such packaging units are known and are already widely used in practice.However, they have the disadvantage that the plastic film is always subjected to a tensile force during unwinding, which can vary over time. The thickness of the plastic film must therefore always be such that it cannot tear if the tensile force temporarily increases. According to the advantageous embodiment of the invention described above, which can also be considered an independent invention, this problem is solved by using the film control unit to determine the tensile force acting on the plastic film and by controlling the motor based on this determined tensile force. By additionally using a motor-assisted unwinding mechanism for the plastic film from the roll, the tensile force can be reduced, allowing the use of thinner plastic films without the risk of tearing due to temporarily increased tensile forces.This allows for significant savings in film material. The shaft is driven by the motor in a conveniently stepless manner, depending on the tensile force acting on the plastic film.

[0008] The film control unit is advantageously configured to start the shaft drive when the tensile force reaches a first threshold. Furthermore, it can be configured to control the shaft drive so that the tensile force does not exceed a second threshold, which is advantageously higher than the first. Finally, the film control unit can be configured to stop the shaft drive when the tensile force falls below a third threshold, which is again advantageously lower than the first threshold.

[0009] Preferably, the film control unit has a deflecting element around which the plastic film is guided and which can be deflected from a rest position depending on the tensile force. Such a deflecting element can also be called a dancer. The deflecting element is advantageously arranged on a lever arm that can be pivoted against a restoring force by the tensile force. If the tensile force increases, the lever arm pivots against the restoring force. The greater the increase in tensile force, the greater the distance or angle by which the lever arm pivots, and the film control unit then controls the motor so that it transmits a higher force or torque to the shaft when the lever arm is deflected more.

[0010] The invention will now be explained in more detail with reference to an exemplary embodiment shown schematically in the drawing. The drawing shows... Figure 1, 2 shows a device for packaging food portions in perspective view and side view.

[0011] The device 10 for packaging food portions, or packaging device 10 for short, shown in the drawing, serves to package food portions 12, in the illustrated embodiment of frozen pizzas, in a plastic film 14. The plastic film 14 is wound onto a roll 16, which is mounted on a shaft 18 rotatably about its longitudinal center axis. The food portions 12 are packaged in the plastic film 14 in a packaging unit 20, to which they are fed by means of a feeding device 22. The feeding device 22 has a carrier 24 in the form of a circulating belt, from which carriers 26 project at constant intervals. These carriers strike the food portions 12 at their rear edge and carry them along, thus providing a feed motion. A conveyor 30 is located upstream of the feeding device 22, which transports the food portions 12 to the feeding device 22.The food portions 12 are transported to the conveying device 30 by means of a transport device not shown in the drawing. The transport of the food portions 12 takes place in both the feeding device 22 and the conveying device 30 in a conveying direction 32.

[0012] The conveying device 30 has several conveyor belts 34 arranged one behind the other in the conveying direction 32. The first conveyor belt 34 in the conveying direction 32 connects directly to the transport device 32, while the last conveyor belt 34 transfers the food portions 12 to the feeding device 22. Each of the conveyor belts 34 is driven by a drive motor 36. The drive motors 36 are individually controlled by a conveyor belt control unit (not shown in detail), which is housed in a casing 40 of the packaging device 10. The control of the drive motors 36 by the conveyor belt control unit is based on signals transmitted to the conveyor belt control unit by sensors 42 designed as light barriers.The sensors 42 detect the food portions 12. The sensor 42 assigned to the second conveyor belt 34 detects the food portions 12 along their entire length, i.e., from the front edge to the rear edge, measured in the conveying direction 32. The other sensors 42, assigned to the other conveyor belts 34, each detect at least the front edge of the food portions 12, thus detecting their arrival at the location of the respective sensor 42. The conveyor belt control unit controls the drive motors 36 such that the food portions 12, which are generally delivered by the transport device at undefined intervals, are brought to predetermined intervals that correspond to the intervals of the carriers 26.The drive motor 36 of the first conveyor belt 34 is controlled by the conveyor belt control unit such that the first conveyor belt 34 moves at a constant speed. When a food portion 12 is transferred from one conveyor belt 34 to the subsequent conveyor belt 34, the conveyor belt control unit controls the respective drive motors 36 so that both conveyor belts 34 move at the same speed. The control of the drive motors 36 by the conveyor belt control unit makes it possible to position the food portions 12 at a distance from each other, so that when food portions 12 are delivered by the transport device to the conveyor 30, a food portion 12 can be transferred to each of the carriers 26.This facilitates the operation of the packaging unit 20 without empty packaging, where the plastic film 14 is only unwound when food portions 12 are ready for packaging. In particular, the abrupt braking and acceleration of the plastic film 14 is largely avoided. Furthermore, the control of the drive motors 36 by the conveyor belt control unit prevents the food portions 12 from colliding with each other in the conveyor 30, which could damage them.

[0013] The packaging device 20 has a packaging unit 50 that packages the food portions 12 in the plastic film 14, cuts film sections from the continuous plastic film 14, and seals the food portions 12 within the film sections. The packaging device 20 also has an unwinding unit 52 that applies tension to the plastic film 14 and unwinds it from the roll 16. The unwinding of the plastic film 14 from the roll 16 is further assisted by a motor 54, which drives the shaft 18. The packaging device 20 has a film control unit 56 that detects the tensile force acting on the plastic film 14 and controls the motor 54 accordingly. The film control unit 56 has a deflecting element 58, which can also be referred to as a dancer, and which is arranged on a lever arm 60.The plastic film 14 is deflected around the deflecting element 58, which is subjected to a force proportional to the tensile force acting on the plastic film 14. This force deflects the deflecting element, or lever arm 60, against a restoring force from a rest position, with the deflection being detected by the film control unit 56. The motor 54 is controlled such that the greater the tensile force, the greater the torque the motor 54 applies to the shaft 18. In this way, the thickness of the plastic film 54 can be kept small without the risk of the plastic film 54 tearing in the event of temporary high tensile forces, since the active unwinding of the plastic film 14 from the roll 16 by the motor 54, which drives the shaft 18, reduces the tensile force acting on the plastic film 14. The foil control unit 56 starts the drive of the shaft 18 by the motor 54 when the tensile force reaches a first threshold value.It controls the drive of shaft 18 by motor 54 such that the tensile force does not exceed a second threshold value, which is greater than the first threshold value. If the tensile force falls below a third threshold value, which is less than the first threshold value, the film control unit 56 stops the drive of shaft 18 by motor 54. On another shaft 18', driven by another motor 54', another roll 16' with another plastic film 14' is mounted. This roll is used when the plastic film 14 is almost completely unwound. The additional plastic film 14' is then sealed to the end of the plastic film 14 and unwound by the unwinding unit 52 to package the food portions 12. The additional plastic film 14' is also guided around the deflecting element 58 to control the additional motor 54' in the same way as motor 54 was previously controlled. In summary, the following can be stated:

[0014] The invention relates to a device 10 for packaging food portions 12, comprising a packaging device 20, a feeding device 22 for feeding the food portions 12 to the packaging device 20 at equal spatial intervals, the feeding device 22 having a circumferential carrier 24 and carriers 26 for the food portions 12 arranged at equal intervals on the carrier 24 and projecting from the carrier 24, and a conveying device 30 for transporting the food portions 12 to the feeding device 22 in a conveying direction 32.According to the invention, the conveying device 30 comprises several conveyor belts 34 arranged successively in the conveying direction 32, each driven by a drive motor 36, a conveyor belt control unit and sensors 42 for detecting the food portions 12, wherein the conveyor belt control unit is configured to control the drive motors 36 of the conveyor belts 34 depending on data obtained from the sensors 42 in such a way that the food portions 12 are brought to spatial distances from each other.

Claims

1. Device for packaging food portions (12) comprising a packaging device (20), a feeding device (22) for feeding the food portions (12) to the packaging device (20) at equal spatial intervals, the feeding device (22) having a circumferential carrier (24) and carriers (26) for the food portions (12) arranged at equal intervals on the carrier (24) and projecting from the carrier (24), and a conveying device (30) for transporting the food portions (12) to the feeding device (22) in a conveying direction (32), characterized by the fact thatThe conveying device (30) comprises several conveyor belts (34) arranged successively in the conveying direction (32), each driven by a drive motor (36), a conveyor belt control unit and sensors (42) for detecting the food portions (12), wherein the conveyor belt control unit is configured to control the drive motors (36) of the conveyor belts (34) depending on data received from the sensors (42) in such a way that the food portions (12) are brought to spatial distances from each other.

2. Device according to claim 1, characterized by the fact that Each conveyor belt (34) is assigned at least one sensor (42) for detecting the food portions (12).

3. Device according to claim 1 or 2, characterized by the fact that the sensors (42) are light barriers.

4. Device according to one of the preceding claims, characterized by the fact thatthe conveyor belt control unit is set up to control the drive motor (36) of the first conveyor belt (34) in the conveying direction (32) in such a way that the first conveyor belt (34) moves at a constant speed and preferably always at a speed that is at least as high as the speeds of the other conveyor belts (34).

5. Device according to one of the preceding claims, characterized by the fact that at least one of the sensors (42), in particular the sensor (42) of the second conveyor belt (34) following the first conveyor belt (34), is designed to detect the food portions (12) over their entire length.

6. Device according to one of the preceding claims, characterized by the fact that the conveyor belt control unit is set up to transfer the food portions (12) individually between two carriers (26) to the feeding device (22).

7. Device according to one of the preceding claims, characterized bya transport device for transporting the food portions (12) to the conveying device (30).

8. Device according to one of the preceding claims, characterized by the fact that The packaging device (20) comprises a shaft (18) rotatably mounted about its longitudinal axis for mounting a roll (16) with wound plastic film (14), an unwinding unit (52) for applying tension and unwinding the plastic film (14) from the roll (16), a packaging unit (50) for packaging the food portions (12) in the plastic film (14), a motor (54) for driving the shaft (18) and a film control unit (56) for determining the tensile force acting on the plastic film (14) and for controlling the motor (54) depending on the determined tensile force.

9. Device for packaging food portions (12) comprising a packaging device (20) and a feeding device (22) for feeding the food portions (12) to the packaging device (20), characterized by the fact that The packaging device (20) comprises a shaft (18) rotatably mounted about its longitudinal axis for mounting a roll (16) with wound plastic film (14), an unwinding unit (52) for applying tension and unwinding the plastic film (14) from the roll (16), a packaging unit (50) for packaging the food portions (12) in the plastic film (14), a motor (54) for driving the shaft (18) and a film control unit (56) for determining the tensile force acting on the plastic film (14) and for controlling the motor (54) depending on the measured tensile force.

10. Device according to claim 8 or 9, characterized by the fact thatthe film control unit (56) has a deflecting element (58) around which the plastic film (14) is guided and which can be deflected from a rest position depending on the tensile force, wherein the deflecting element (58) is preferably arranged on a lever arm (60) which can be pivoted against a restoring force by the tensile force.

11. Device according to one of claims 8 to 10, characterized by the fact that the foil control unit (56) is set up to start the drive of the shaft (18) when the tensile force reaches a first threshold value.

12. Device according to one of claims 8 to 11, characterized by the fact that the foil control unit (56) is set up to control the drive of the shaft (18) so that the tensile force does not exceed a second threshold value.

13. Device according to any one of claims 8 to 12, characterized by the fact that the foil control unit (56) is set up to stop the drive of the shaft (18) when the tensile force falls below a third threshold.

14. Method for operating a device according to one of claims 1 to 8, wherein the conveyor belt control unit controls the drive motors (36) of the conveyor belts (34) depending on data obtained from the sensors (42) so that the food portions (12) are brought to spatial distances from each other, wherein the conveyor belt control unit preferably controls the drive motors (36) of the conveyor belts (34) depending on the movement of the carrier (24) so ​​that the food portions (12) are each placed individually between two carriers (26).

15. Method for operating a device according to one of claims 8 to 13, wherein the foil control unit (56) determines the tensile force and controls the motor (54) depending on the determined tensile force.

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