WO2018229806A1

WO2018229806A1 - Packaging machine with tray detection system and operating method thereof

Info

Publication number: WO2018229806A1
Application number: PCT/IT2018/050105
Authority: WO
Inventors: Tomaso PETRINI
Original assignee: Italianpack S.R.L.
Priority date: 2017-06-14
Filing date: 2018-06-11
Publication date: 2018-12-20
Also published as: IT201700066109A1

Abstract

Food tray packaging machine comprising automatic detection means (3, 4) for input tray size, and positioning means capable of locating the tray (1) to be packaged at the corresponding packaging bell-chamber (6), as well as operating method thereof.

Description

PACKAGING MACHINE WITH TRAY DETECTION SYSTEM AND OPERATING

METHOD THEREOF The present invention regards a packaging machine for products, in particular, foods or any materials, in general, and operating method thereof.

Vacuum packaging machines generally equipped with a bell-shaped chamber are known, which further comprise a vacuum pump placed in communication with the bell-shaped chamber, also referred to as vacuum chamber, wherein one or more trays may be placed on corresponding moulds or matrices that are provided for such chamber, each tray being pre-formed and open at the top, where a food product or any material, in general, is placed therein, subsequently sealed with a plastic film via heat sealing inside the packaging machine itself.

If the packaging machine is to be used to package trays of different sizes, the operator will need to manually replace the mould being used with a mould corresponding to the desired tray size to be packaged. Such operation necessarily involves a machine stop and intervention, which nevertheless involves a certain amount of time, as well as complex operations from the maintenance man/operator himself.

Such drawbacks have a great impact in the field of food packaging machines used in sales points, such as supermarkets, where it is necessary to frequently change moulds to be able to meet packaging requirements for a wide variety of foods.

In order to understand the complexity of mould replacement operations following a change in the size of the tray to be packaged, it is first necessary to state that such mould consists of a hot upper element having the shape of the tray to be packaged, a wrapper cutting die that follows the outline of the tray and will cut the packaging film, and a lower element (called tray holder) that makes up the housing of the same tray for sealing and cutting operations.

Machines are also known which provide for the upper element of the mould to be changed automatically once the machine is stopped, thus giving the system more flexibility; such upper element is in fact equipped with two or more (generally four) moulds having two or more vacuum chambers that are serially arranged to one l another or rotate on a horizontal axis.

However, in order to change the mould with this technical solution, after stopping the machine, the operator should select which mould will be used, and once the mould is selected, it will be pre-heated and successively used by the packaging machine.

It should be noted, however, that the operation of manually selecting the tray size upstream of the packaging operation involves, in addition to a loss of production time for the packaging machine itself, also possible setting errors from the operator himself.

A further drawback of the known packaging machines consists in that they are mechanically complex and require complicated maintenance interventions, as well as complicated operational interventions in case the moulds are replaced.

The main object of the present invention is to solve the technical problems highlighted, eliminating the drawbacks of the aforementioned prior art and obtaining a versatile packaging machine which is particularly suitable for sales points/supermarkets where it is necessary to package various types of foods with different technologies, which thus make it necessary to change moulds frequently.

The object of the present invention is a packaging machine equipped with an automatic detection system for input tray size and operating method thereof.

An object of the present invention is to accomplish a packaging machine equipped with a system allowing for the automatic detection of the tray size to be packaged at input, such that it can be conveyed to the corresponding bell packaging chamber without any manual intervention by the operator.

In particular, an object of the present invention is to accomplish a packaging machine equipped with a simple automatic detection system for input tray size, equipped with a minimum number of mechanical components, and thus easy and cost-effective to maintain.

A further object of the present invention is to achieve a packaging machine equipped with an alternative double automatic recognition system for input tray size, thus capable of functioning in any operational and environmental condition.

Still another object of the present invention is to accomplish a packaging machine equipped with an automatic detection system for input tray size, as well as detection of the type of tray within the machine itself, said system being easy to maintain, replace and install.

A further object of the present invention is to achieve a method for automatically recognising the tray size at the packaging machine input, such that it is automatically conveyed to the corresponding mould.

Still another object of the present invention is to achieve a method for automatically recognising the tray size to be packaged inside a packaging machine, as well as a method for automatically recognising the mould of a packaging bell- chamber inserted in the packaging machine, both minimising manual intervention by the operator.

The above and other objects will be accomplished by the packaging machine equipped with an automatic detection system for input tray size, said system alternatively making use of mechanical means and video means as, as well as an automatic detection system for the type of mould in a packaging bell-chamber of the machine.

The object of the present invention will be illustrated in detail in the attached figures and description thereof, where only some of the possible innovative embodiments are described, wherein:

Fig. 1 shows a three-dimensional view of the machine object of the invention; Fig. 2 shows a detail of the input area of the machine object of the invention, highlighting both automatic detection systems for tray size according to the invention;

Fig. 3 shows a detail of the parts making up two packaging bell-chambers, of which one with one matrix, and the other with two matrices;

Fig. 4 shows a detail of the tray handling system and the travel means inside the machine, where each packaging bell-chamber is programmed in the example to operate with two matrices,

Fig. 5 shows a detail of a machine mould according to the invention,

Fig. 6 shows a detail of the machine according to the invention, highlighting the mould detection system,

Fig. 7 shows a rear view of the machine object of the invention according to a three-dimensional view,

Fig. 8 shows a detail of the roller system for handling the packaging film in the machine object of the invention.

In particular, with reference to Figure 1 , an overall view of the machine object of the invention is shown. It is composed of one or more packaging bell-chambers 6, for packaging different tray sizes, said one or more packaging bell-chambers 6 comprising in turn a mould 60 of pre-established sizes for each packaging bell- chamber 6, or a heating element having the shape of the tray to be packaged, a wrapper cutting die adapted for following the outline of the tray to be packaged and adapted for cutting the packaging film 9 to the appropriate size, and a suitable technology (PACK/VAC/SKIN) and a lower element, usually referred to as tray holder 61 , that makes up the housing and tray match for sealing and cutting the mould 60 located above. The machine further comprises a tray handling system 1 comprising in turn a powered conveyor belt or input belt 10 for carrying the tray to be packaged at the machine input, an initial positioning belt 11 a to correctly position the tray inside the inner corridor 11 downstream, in relation to the subsequent packaging with one or more matrices, travel means 5 (preferably travel rods) which is configured to move the tray and positions it at the packaging bell-chamber 6 that is to perform packaging, and an output belt 12 equipped downstream with an ejection belt 13 for delivering the packaged tray to the operator.

Located at a specific position on the input belt 10 is an input door 2A, which, when open, allows the tray to be packaged to enter inside the machine.

Automatic detection of tray size takes place via automatic detection means 3, 4 based on the shape of the tray detected on the input belt 10 (see Fig. 2), specifically:

a) an appropriate camera 3 positioned above the input belt 10 is configured to perform scanning of the input belt 10 and to detect one or more tray sizes to be packaged, if present above the input belt 10, thus detecting the size in a successive step. Camera 3 recognises the size of the tray to be packaged even if the tray is not perfectly in line with the driving axis of the input belt 10, because such camera 3 detects the emissions of a preferably infra-red emitter (not shown in the Figures) placed inside the structure of input belt 10, said preferably infra-red emitter, the emissions of which cross the cloth band of the input belt 10, but not the tray placed above the input belt itself, and are detected, therefore, by the camera 3. Camera 3 is also equipped with an internal storage in which the tray sizes that the machine is capable of packaging inside the packaging bell-chambers 6 with which it is equipped are preloaded, and a suitable control and management unit that is capable of comparing the one or more sizes detected by camera 3 with the tray sizes pre-loaded into the internal storage of camera 3, thus determining the actual size of the tray to be packaged and transmitting appropriate signals for controlling the handling of the initial positioning belt 11 a, the positioning pallet 50 (or also a feed pusher, a rod or else) and the travel elements 5 (preferably travel rods, or, in any case, also feed pushers or else) inside the machine, so that the tray to be packaged is correctly conveyed to the corresponding packaging bell-chamber 6.

b) a sensor 4, for example, a photocell, positioned on the input belt 10 side that detects the presence or absence of the tray on the belt itself, when it passes in front of sensor 4, thus knowing the speed of input belt 10 on the basis of the time for which sensor 4 detects the presence of the tray, it is capable of calculating the length of the tray and, as a result, determining tray size. Such measurements detected and data calculated are sent to the control and management unit of the machine through appropriate means for transmitting the signals detected by sensor 4, which determine, based on the sizes pre-loaded into the internal storage of the machine, the corresponding size of the input tray, and thus drives the handling of the initial positioning belt 11 a, the positioning pallet 50 (or also a feed pusher, a rod or else), and the travel means 5 (preferably travel rods, or in any case, also feed pushers or else) inside the machine, such that the tray to be packaged is correctly brought to the corresponding packaging bell-chamber 6.

The method for automatically recognising the size of the trays to be packaged in the packaging machine object of the invention comprising, in the event the automatic detection elements 3, 4 consist of the camera 3, at least the following steps of:

i) placing the tray to be packaged on an input belt 10 of the machine, ii) emitting infra-red emissions from an emitter placed inside an input belt 10; iii) analysing the emissions received by an infra-red camera,

iv) detecting the one or more sizes of the tray placed above the input belt 10 and affected by such infra-red emissions,

v) comparing the one or more sizes of the tray detected with a series of standard sizes preloaded into an internal storage of the camera 3, determining the correct size of the tray positioned above the input belt 10.

vi) communicating the size of the tray recognised to a machine control and management unit, which in turn controls the actuation of a tray handling system 1 in order to carry the tray to be packaged to the corresponding packaging bell-chamber 6.

The method for automatically recognising the size of the trays to be packaged in the packaging machine object of the invention comprising, in the event in which the automatic detection elements 3, 4 consist of sensors 4, at least the following steps of: i) positioning the tray to be packaged on an input belt 10 of the machine, ii) detecting the presence of a tray on the input belt 10 by means of a sensor 4 positioned on the input belt 10 side, as well as the time it takes for such tray to pass in front of the sensor 4,

iii) calculating the length and therefore the size of the tray on the input belt 10, when the tray passes in front of sensor 4, with the speed of the input belt 10 being known, based on the time it takes for sensor 4 to detect the presence of the tray on the input belt 10.

iv) communicating the size of the tray detected to a machine control and management unit via appropriate means for transmitting signals detected by sensor 4, said control and management unit determines the size of the input tray based on the sizes pre-loaded into the internal storage of the machine, and controls the actuation of a tray handling system 1 in order to send the tray to be packaged to the corresponding packaging bell-chamber 6.

As stated above, the machine provides for one or more (in any case, at least two) packaging bell-chambers 6 to perform the packaging of at least two different tray sizes, each comprising a corresponding forming mould 60 placed above and a tray holder 61 placed below (see Figs. 2, 3, 4). Each forming mould 60 may be dedicated to the packaging of a specific tray size. Moreover, each packaging bell-chamber 6 can provide for different packaging technologies, such as for example: PACK, in which the tray is only heat sealed with a cover film 9; VAC, in which a vacuum is created inside the packaging bell-chamber 6, and therefore the tray, after which gas is introduced inside the tray to compensate for the pressure difference with the outside, and therefore the tray is heat sealed with a cover film 9; SKIN, in which a vacuum is created both inside the packaging bell-chamber 6 and the tray, making the film 9 come into contact with the tray and the product contained therein, adhering to it, after which the film 9 is heat sealed. According to the machine object of the present invention, a multi-size and multi-technology machine is obtained, because it provides for several packaging bell- chambers 6, the exemplary embodiment contains four, each of which, in addition to being provided for a certain packaging size, can also provide for one or more packaging technologies, because a mould 60 with SKIN technology, for example, can be used for operation with the VAC and PACK technology, or it can also be used with the VAC technology for operation with a PACK technology, whereas the mould 60 for the PACK technology can operate only with that technology.

The machine object of the present invention is further able to perform packaging on several tracks/matrices, or to package one or more trays next to one another in each mould 60, in such a case, a positioning pallet 50 that operates at the initial positioning belt 11 a at the entry of inner corridor 11 , provides for correctly positioning and aligning the trays, when it is necessary to carry out packaging on several matrices.

It should be noted that both the packaging technology mode and the packaging on one or more matrices are automatically managed by the machine object of the invention, based on the automatic detection that occurs on the input belt 10 by the camera 3 or the sensor 4. Therefore, if the automatic detection means 3, 4 detect a certain size X for the input tray, assuming that the machine object of the invention is configured so that the third bell-chamber 6 in the direction of travel of the travel means 5 inside the inner corridor 11 is programmed for VAC packaging of tray size X, then the travel means 5, in conjunction with the movement of the initial positioning belt 11 a, convey the tray size X at the third packaging bell-chamber 6. On the contrary, assuming that the machine object of the invention is configured so that the second bell-chamber 6 in the feed direction inside the inner corridor 11 is programmed for the SKIN packaging of a tray size Y on a double matrix, if the automatic detection means 3, 4 detect a tray size Y, then the travel means 5, in conjunction with the movement of the initial positioning belt 11 a, will convey the tray size Y at the second bell-chamber 6, positioning the tray Y on the matrix corresponding to mould 60 of the related packaging bell-chamber 6.

Once the packaging is completed, when the trays are in a pre-established position on the output belt 12, the output door 2b lifts open and the output belt 12 starts to operate bringing the trays onto the ejection belt 13. The machine object of the invention is configured so that every mould 60 of different size is automatically detectable once it is introduced into the machine by means of a mould detection system 7 (see Figs. 5, 6) comprising appropriate sensors 70 for detecting mould 60 capable of detecting the presence and the number of appropriate matches 71 on specific holes made on the moulds 60, said matches 71 being in such number as to correspond to a pre-set mould 60, which corresponds in turn to a tray size and the corresponding packaging technology one wishes to accomplish for that tray size. In this way, once the mould 60 is inserted, the machine automatically reads the type of mould 60 involved and detects the size of input tray by the automatic detection means 3, 4, and conveys it for packaging to the corresponding mould 60.

The method for automatically recognising the mould 60 inserted into a packaging machine object of the invention, comprising at least the following steps of:

- positioning on a mould 60 a number of matches 71 corresponding to a corresponding identification of mould 60;

- detecting the number of matches 71 on the mould 60 through sensors 70 inside the machine;

- communicating the type of mould (60) recognised to a machine control unit, said control and management unit which, knowing the position of the mould 60 detected inside the machine will correspondingly control a system for handling trays 1 to be packaged, interacting or not with the method for automatically recognising the tray size to be packaged placed on the input belt 10 that makes use of either camera 3 or sensors 4.

Moreover, at each packaging bell-chamber 6 is a roller system 8 (see Figs. 7, 8) comprising a series of idler rolls 80 for guiding and moving the packaging film 9 from the film reel, placed upstream of the packaging bell-chamber 6, to a powered roll 81 that allows the film 9 to be rewound downstream of the packaging bell- chamber 6, in order to position the film reel used for the packaging itself. Such film reels are positioned on the upper rolls 82 together with plates 83, preferably made up of white polyethylene, which are flanked side by side and held against the sides of the reel so as to prevent such film reels from moving and being displaced decentring from their correct position during operation, thus compromising the packaging step. Further variations where the elements making up the machine or its components are combined in different ways by contrasting of parts, by engagement, by jointing of the constitutive elements, or alternative assembly of the constitutive elements of the system, and the operation thereof, are to be considered object of the present invention, wherein, therefore, even alterations and changes regarding, for example, the geometries selected for the individual movable and fixed elements, the materials adopted for each member, and also the specifications of the automatic detection system or modifications to software adjustments, can be made without departing, for this reason, from the scope of protection of the present invention, as defined in the claims attached hereto.

List of reference numbers:

1 tray handling system, 10 input belt, 11 inner corridor, 11 a initial positioning belt, 12 output belt, 13 ejection belt,

2a input door, 2b output door,

3 camera,

4 sensor,

5 travel means, 50 positioning pallet,

6 packaging bell-chamber, 60 mould, 61 tray holder,

7 mould recognition system, 70 sensors, 71 matches

8 roller system, 80 idler rolls, 81 powered roller, 82 upper rollers, 83 plates

9 film.

Claims

1 . A packaging machine comprising at least two packaging bell-chambers (6) for packaging at least two corresponding tray sizes, each of said at least two packaging bell-chambers (6) providing for a mould (60) inside it for packaging a corresponding tray size, a system for handling trays (1 ) to be packaged adapted for carrying and positioning the trays to be packaged from an input belt (10) to an initial positioning belt (11 a), travel means (5) within the inner corridor (11 ) configured to travel and position the tray to the packaging bell-chamber (6) corresponding to the size of the tray to be packaged, means for automatically detecting (3, 4) one or more tray sizes to be packaged at the machine input, positioned at the input belt (10) and configured so as to recognise the tray size to be packaged on the basis of the shape of the mould detected on the input belt (10) for carrying the tray to the corresponding packaging bell-chamber (6) for packaging the tray of the size corresponding to the sizes detected by said automatic detection means (3, 4).

2. The machine according to claim 1 , wherein the automatic detection means

(3, 4) comprise a camera (3) positioned above the input belt (10), the input belt being configured to perform a scan of the input belt (10) and to detect the emissions from an emitter placed inside the input belt (10) structure, said emissions capable of crossing the cloth band of the input belt (10), but not the tray to be packaged, and being detected by the camera (3).

3. The machine according to claim 2, wherein the emissions from the emitter are infra-red emissions and the camera (3) is an infra-red camera.

4. The machine according to claim 2, wherein the camera (3) further comprises an internal storage in which the sizes of the trays that the machine can package in the packaging bell-chambers (6) with which it is equipped are preloaded, as well as a control and management unit that is capable of comparing the one or more tray sizes detected by the camera (3) with the tray sizes pre-loaded into the internal storage of the camera (3), thus determining the actual size of the tray to be packaged.

5. The machine according to claim 1 , wherein the automatic detection means

(3, 4) consist of a sensor (4), positioned on the input belt (10) side, adapted for detecting the presence or absence of the tray on the input belt (10), as well as the time it takes said tray to pass in front of the sensor (4).

6. The machine according to claim 5 further comprising means for transmitting the signals detected by the sensor (4), a control and management unit for receiving and processing such signals.

7. The machine according to any one of the preceding claims comprising a mould recognition system (7) comprising sensors (70) for recognising the mould (60) installed inside the machine, said sensors (70) being capable of detecting the presence and the number of matches (71 ) present on the mould (60), so that once the mould (60) is inserted, the machine automatically recognises the type of mould (60) inserted and its technical characteristics.

8. A method for automatically recognising the tray size to be packaged in a packaging machine according to claims 1 to 7 comprising the following steps of:

(i) positioning the tray to be packaged on a machine input belt (10);

(ii) emitting infrared emissions by an emitter placed inside an input belt (10);

(iii) analysing the emissions received by an infrared camera,

(iv) detecting one or more sizes of the tray placed above the input belt (10) and affected by such infrared emissions;

(v) comparing the one or more of the tray sizes detected with a set of standard sizes pre-loaded into the internal storage of the camera (3), determining the correct size of the tray placed above the input belt (10);

(vi) communicating the size of the tray recognised to a control and management unit of the machine, which in turn drives activation of a tray handling system (1 ) in order to carry the tray to be packaged to the corresponding packaging bell-chamber (6).

9. A method for automatically recognising the tray size to be packaged in a packaging machine according to claims 1 to 7 comprising the following steps of:

(i) positioning the tray to be packaged on a machine input belt (10),

(ii) detecting the presence of a tray on the input belt (10) by means of a sensor (4) positioned on the input belt (10) side, as well as the time it takes said tray to pass in front of the sensor (4),

(iii) calculating the length, and therefore the size of the tray positioned on the input belt (10), the speed of the input belt (10) being known, based on the time it takes the sensor (4) to detect the presence of the tray on the input belt (10).

(iv) communicating the size of the tray detected to a control and management unit of the machine by means of appropriate means for transmitting the signals detected by the sensor (4), said control and management unit of the machine, which determines the corresponding input tray size, based on the sizes pre-loaded into the internal storage of the machine, and drives actuation of a tray handling system (1 ) to carry the tray to be packaged to the corresponding packaging bell-chamber (6).

10. A method for automatically recognising the mould (60) inserted into a packaging machine according to claims 1 to 7 comprising the following steps of:

- positioning a predetermined number of matches (71 ) on the mould (60) that correspond to a corresponding identification of the mould (60),

- recognising the number of matches (71 ) on the mould (60) by means of sensors (70) placed inside the machine;

- communicating the type of mould (60) recognised to a control and management unit of the machine, such control and management unit, which, knowing the position of the mould (60) detected inside the machine, will correspondingly drive a system for handling trays (1 ) to be packaged by interacting with a method for automatically recognising the size of the trays to be packaged placed on an input belt (10) of a packaging machine according to claim 8 or 9.