ES2460467A2 - Horizontal flexible container forming and filling machine and method for controlling a cutting device of said machine - Google Patents

Abstract

The machine comprises a conveyor device moving a continuous band of preformed containers (BP) step by step in a forward movement direction (D), a cutting device (2) with cutting blades (3a, 3b) operated for cutting the continuous band of preformed containers (BP) transversely in sites related with transverse welding lines (ST) of the continuous band of preformed containers (BP), and an automatic cutting correction device comprising detection means (4) arranged for detecting a plurality of successive detectable elements (21) in the continuous band of preformed containers (BP), and an actuator (5) operatively connected for moving and positioning the cutting device (2) along guide means parallel to the forward movement direction (D) in response to a positioning signal generated from a detection signal emitted by said detection means (4).

Description

HORIZONTAL MACHINE FORMER AND FILLER OF FLEXIBLE PACKAGING, AND CONTROL METHOD OF A MACHINE SAID CUTTING DEVICE

Technical field

The present invention relates in general to a horizontal machine for forming and lining of flexible packages and more particularly to a horizontal machine for forming and lining of flexible packages provided with a cutting device for cutting continuous band of preformed containers and an automatic correction device of cut that corrects the position of the cutting device based on slight variations in the site of the continuous band of

10 preformed containers where the cut should be made,

The present invention also concerns a control method for controlling said automatic cutting correction device associated with the cutting device,

Background of the invention

The ES 2369459 M patent discloses a horizontal forming and lining machine for

15 flexible packages comprising a band supply unit that supplies a heat-weldable sheet band from a coil, a packaging forming unit that forms individual flexible packages from said sheet band, and a filling unit that fills the Individual flexible packaging with one or more products, closes them and delivers them to an outgoing conveyor. The packaging forming unit includes a

20 folding station, where the sheet band is folded longitudinally in the form of "V" or "W", welding stations, where a plurality of lower and transverse welding lines are made defining a continuous band of preformed containers with a plurality of preformed containers, and a cutting station where the continuous band of preformed containers is cut transversely to form the

25 individual flexible packages,

Said cutting station includes one or more pairs of cutting blades between which the continuous band of preformed containers passes, and cutting drive means that cyclically move said cutting blades to transversely cut the continuous band of preformed containers at sites. related to said transverse welding lines 30 and thus forming individual flexible packages, The position of the cutting blades in the cutting station is selected according to the position of some welding elements in the welding station, for the purpose of making match those mentioned

sites where cross cuts are made with said sites related to cross welding lines.

Typically, the transverse welding lines are grouped by pairs of welding lines separated by a small space, and the cuts are made in this small space, so that the front welding line of each pair forms a trailing edge of a flexible container individual and the rear welding line forms the leading edge of the next individual flexible container. Alternatively, the transverse weld lines may include relatively wide individual weld lines, and the cuts are made in the middle of these relatively wide weld lines, with an equivalent result.

Due to a certain elasticity that the sheet generally exhibits from which the continuous band of preformed containers is made, and other factors, such as the effect produced by the welds on the sheet, the position of the sites related to the welding lines cross sections where the cuts should be made may experience small variations along the continuous band of preformed containers.

A drawback of machines of the type described in the aforementioned patent ES 2369459 M is that the position of the cutting blades in the cutting station can be adjusted at the beginning of the work but not during the operation of the machine, which has as a result that sometimes the cuts are not made at the planned sites and that the individual flexible packages obtained are inadequate. The negative result worsens over time due to the accumulation of errors in the positions of the sites where the cuts should be made.

Exhibition of the invention

The present invention aims to solve the above and other inconveniences by providing a horizontal machine forming and liner of flexible packaging provided with an automatic cutting correction device, as well as a method of controlling the cutting device by means of said automatic cutting correction device. .

According to a first aspect, the present invention provides a horizontal forming and liner machine for flexible packaging comprising a conveyor device that moves a continuous band of preformed containers in a forward direction step by step, and a cutting device having one or more pairs of cutting blades arranged so that the continuous band of preformed containers passes between the two cutting blades of each pair. The continuous band of preformed packages has a plurality of transverse welding lines that define a plurality of preformed packages, and the cutting device includes cutting drive means that move said cutting blades to transversely cut the continuous band of preformed packages. at sites related to said transverse welding lines, and thus form individual flexible packages.

The cutting device is associated with an automatic cutting correction device comprising detection means located upstream of the cutting device and arranged to detect a plurality of successive detectable elements in the continuous band of preformed containers, and an actuator that moves and positions the cutting device along guide means parallel to the direction of travel in response to a positioning signal generated from a detection signal emitted by said detection means.

The aforementioned detectable elements may be constituted by contours, cuts, notches, etc., formed on a longitudinal edge of the continuous band of preformed containers, or by printed indications on the continuous band of preformed containers, but in any case the detectable elements they are positioned consecutively in relation to the transverse welding lines and there is less one detectable element associated with each preformed container of the continuous band of preformed containers.

In one embodiment, the detection means includes an artificial vision device fixed to a machine bed and arranged to capture consecutive images of consecutive portions of the continuous band of preformed containers, where each of said consecutive portions includes at least one of said detectable elements. Optionally, the detection means further includes a lighting device, such as a flash, associated with said artificial vision device.

According to a possible embodiment, the cutting device comprises a base support fixed to the machine bed, and a mobile support, in which said one is installed

or more pairs of cutting blades and said cutting drive means, mobilely connected to said base support by the guide means. In this case, said actuator has a fixed body fixed to the base support and a mobile element connected to the mobile support, or vice versa. Preferably, the fixed actuator body comprises an electric servomotor, the operation of which can be precisely controlled by electronic control means, and the mobile element of the actuator comprises an extensible rod actuated by the servomotor through a mechanical transmission.

In a particular embodiment, the guide means comprise a slide fixed to said

5 mobile support and one or more sliding guide elements fixed to the base support and mobilely coupled to said slide. For example, the slide may have some convergent inclined side surfaces from top to bottom, and correspondingly said one or more sliding guide elements may comprise elements of rolling mounted on the base support and arranged to roll on said surfaces

10 inclined sides of the slide, so that the mobile support fixed to the slide is supported on said rolling elements and has freedom of movement in said direction parallel to the direction of travel.

One or more pairs of band guide elements arranged in fixed positions are installed on the mobile support of the cutting device so that between the two

15 band guide elements of each pair passes the continuous band of preformed containers. Each pair of band guide elements is disposed in an adjacent position and upstream of one of the one or more pairs of cutting blades and acts to hold the continuous band of preformed containers when cut by the corresponding pair of cutting blades. .

In accordance with a second aspect, the present invention provides a method of controlling a cutting device of a horizontal flexible forming and liner machine such as that described according to the first aspect of the present invention. The method comprises the steps of detecting by means of detection means located upstream of the cutting device a plurality of successive elements detectable in the

25 continuous band of preformed containers, and moving and positioning the cutting device along guide means parallel to said direction of advance by means of an actuator in response to a positioning signal generated from a detection signal emitted by said detection means.

The method comprises using, as a component of said detection means, a

30 artificial vision device, in which case said detection step comprises capturing by means of said artificial vision device consecutive images of consecutive portions of the continuous band of preformed containers, where each of said consecutive images includes at least one of said elements detectable, and emit said detection signal, which is representative of the consecutive images.

Next, the method comprises using electronic control means to compare the consecutive images taken by the artificial vision device with a predefined image pattern stored in a memory, and generating said positioning signal when a deviation between one of the sensors is detected. Consecutive images taken by the artificial vision device and said image pattern.

As indicated above, the machine's conveyor device moves the continuous band of preformed containers by a step-by-step movement that combines forward movements with short periods of downtime during which the cutting device makes the cut. According to this characteristic, the method also includes controlling by means of the electronic control means the operation of the artificial vision device in coordination with the operation of the conveyor device, so that the consecutive images are taken by the artificial vision device during the periods of time in which the continuous band of preformed containers is stopped between consecutive forward movements.

Brief description of the drawings

The above characteristics and advantages will be more evident from the detailed description of an embodiment with reference to the attached drawings, in which:

Fig. 1 is a perspective view of a horizontal flexible packaging and forming machine according to an embodiment of the present invention;

Fig. 2 is a perspective view of a cutting station of the machine of Fig. 1, including a cutting device associated with an automatic cutting correction device, shown in relation to a continuous band of preformed containers to be cut. ;

Fig. 3 is a side view of the continuous band of preformed containers of Fig. 2;

Fig. 4 is a plan view of the cutting device of Fig. 2;

Fig. 5 is a cross-sectional view taken on the v-v plane of Fig. 4; Y

Fig. 6 is a cross-sectional view taken along the plane VI-VI of Fig. 4.

DETAILED DESCRIPTION OF AN EMBODIMENT EXAMPLE Referring first to FIG. 1, there is shown a horizontal forming and liner machine for flexible packaging according to an embodiment of the present invention, which essentially comprises a delivery unit of band 100 which supplies a strip of heat-weldable sheet B from a coil 101, a unit of

5 formation of packages 200 forming individual flexible packages E from said sheet band B, and a filling unit 300 that fills the individual flexible packages E with one or more products, close them and deliver them to an outbound conveyor 330.

The container forming unit 200 includes a folding station 210, where the strip of sheet B is folded longitudinally in the form of "V" or "W", 1 or welding stations 211, 212, where a plurality of lower welding lines SI and transverse welding lines ST defining a continuous band of preformed containers BP (see also Fig. 3), which comprises a plurality of preformed containers EP defined by said transverse welding lines ST, and a station cutting 220 where the continuous band of preformed containers BP is cut

15 transversely to form the individual flexible packages E. A conveyor device (not shown) moves the continuous band of preformed containers BP step by step in a forward direction O along the container forming unit 200.

Fig. 3 shows an example of a continuous band of preformed containers BP, which comprises the mentioned transverse welding lines ST grouped in groups of

20 two, where the two transverse welding lines ST of each group are separated by a small space G along which the transverse cut must be made to form the individual flexible packages E, so that the front ST welding line of each group of two forms a rear edge of the newly separated individual flexible container E and the rear ST welding line of each group of two will form the edge

25 front of the next individual flexible container E.

The continuous band of preformed containers BP has its upper edge free of welding, so that the preformed containers EP have an upper opening through which they will be filled with one or more products by means of metering devices 310 in the filling unit 300, and later this upper opening will be closed by a

30 upper welding line (not shown) at an additional welding station 320 of the filling unit 300.

Notches M are formed next to said upper edge of the continuous band of preformed containers BP shown in Fig. 3, each of which defines a vertical edge

MV aligned with the space between each group of two transverse welding lines ST and an inclined edge MI in which a nozzle and plug group T previously installed in a corresponding station (not shown) of the packaging forming unit is arranged 200. Each transverse cut must coincide with the mentioned vertical edge MV of the corresponding notch M to avoid malformations in the front and rear edges of the individual flexible packages E, so that the positioning of the cuts is critical.

The vertices formed by the confluence of the vertical edges MV of the aforementioned notches M with the upper edge of the continuous band of preformed containers BP are used as detectable elements 21 in the cutting control method of the horizontal forming machine and container liner flexible features of the present invention, as will be explained below. However, one skilled in the art will understand that the continuous band of preformed containers BP can have a multitude of different configurations from that shown in Fig. 3, and that other characteristics of the continuous band of preformed containers BP, such as indications or printed marks, may alternatively be used as elements detectable by the device and method of the present invention.

Fig. 2 shows in greater detail the said cutting station 220, which comprises a cutting device 2 associated with an automatic cutting correction device. The cutting device 2 comprises two pairs of cutting blades 3a, 3b between which the continuous band of preformed containers BP passes and cutting drive means (not shown) that close and open these two pairs of cutting blades 3a, 3b for a short period of time in which the continuous band of preformed containers BP is stopped between consecutive forward movements of its step-by-step movement to cross-section the continuous band of preformed containers BP at sites between the two transverse welding lines ST of each group of two and thus form the individual flexible containers E.

The cutting device 2 comprises a base support 9 fixed to a machine bed (not shown), and a mobile support 10 in which the two pairs of cutting blades 3a, 3b are installed, which can rotate around a common shaft 22, and the aforementioned cutting drive means. Two pairs of band guide elements 12a, 12b are also installed on the mobile support 10 between which the continuous band of preformed containers BP passes. Each of these pairs of band guide elements 12a, 12b is in an adjacent position and upstream of one of the two pairs of cutting blades 3a, 3b. Thus, the continuous band of preformed containers BP is held by the pairs of band guide elements 12a, 12b at the moment that the pairs of cutting blades 3a, 3b are actuated to cut it.

This mobile support 10 is mobilely connected to the base support 9 by guide means parallel to said forward direction D. An actuator 5 is operatively connected to move and position the cutting device 2 along said guide means in response to a positioning signal generated by electronic control means from a detection signal emitted by a detection means 4 located upstream of the cutting device 2, which will be described below.

Said actuator 5 has a fixed body 5a fixed to the base support 9 and a mobile element 5b connected to the mobile support 10, although alternatively the assembly could be the reverse, that is, the fixed body 5a fixed to the mobile support 10 AND the element mobile 5b connected to the base support 9. In the illustrated example, the fixed body 5a includes an electric servo motor and the mobile element 5b includes an extensible rod connected to the electric servo motor by a mechanical transmission including an angled transmission 5c.

As shown in Figs. 5 and 6, the guide means comprise a slide 6 fixed to the mobile support 10 And one or more slide guide elements fixed to the base support 9 and movably coupled to the slide 6. For example, the slide 6 has surfaces inclined sides 6a that converge from top to bottom, and those mentioned one

or more slide guide elements comprise rolling elements 13 mounted on the base support 9 and arranged to support the slide 6 and roll on said inclined side surfaces 6b of the slide 6.

Thus, the mobile support 10 is supported on the base support 9 and has the possibility of movement along the slide 6 in the direction parallel to the forward direction D. The mobile element 5b of the actuator 5 is connected to the slide 6 of the mobile support 10 for a connection element 14.

As shown in Fig. 6, a pair of camshafts 11 a, 11 b parallel to the direction of travel D are mounted on the base support 9, which are rotatably rotated by actuation means (not shown ). These camshafts 11 a, 11 b are connected to oscillatingly move respective cam bars 19a, 19b coupled to corresponding forks 20a, 20b respectively integral with the cutting blades 3a, 3b of each pair. The aforementioned forks 20a, 20b can slide longitudinally along the cam bars 19a, 19b without decoupling thereof when the mobile support 10 is moved along the slide 6.

Said automatic cutting correction device (Fig. 1) comprises the detection means 4 mentioned above, which in the illustrated example include an artificial vision device 7 located upstream of the cutting device 2 and arranged to capture images consecutive portions of consecutive portions of the continuous band of preformed containers BP, where each of said consecutive portions includes one of the detectable elements 21, that is to say one of the notches M. Thus, each of the consecutive images captured by the device of artificial vision 7 includes one of said detectable elements 21, that is, one of the notches M.

The detection means 4 emit a detection signal, which is representative of the consecutive images captured. Said electronic control means include a memory in which a predefined image pattern is stored. According to the method of the present invention, the electronic control means compares the consecutive images taken by the artificial vision device 7 with said predefined image pattern and generates a positioning signal mentioned above when a deviation between one of consecutive images taken by the artificial vision device 7 and the stored image pattern.

Then, the actuator 5 moves and positions the cutting device in accordance with this positioning signal to precisely match the transverse cuts made by the pairs of cutting blades 3a, 3b with the vertical edges of the notches M of the continuous web of preformed BP containers.

Preferably, the operation of the artificial vision device 7 is controlled by the electronic control means in accordance with the operation of the conveyor device, so that consecutive images are taken during periods of time in which the continuous band of preformed containers BP it is stopped between consecutive forward movements of its movement step by step. Optionally, the detection means 4 further includes a lighting device 8, for example a flash lamp, associated with said artificial vision device 7.

In the embodiment illustrated in Fig. 1, the artificial vision device 7 and the lighting device 8 of the detection means 4 are fixed to the machine bed by means of adjustment means that allow the position of the means of detection with respect to the bed and therefore with respect to the continuous band of preformed containers BP.

Thus, the artificial vision device 7 and the lighting device 8 are mounted on a detection support 15 connected to a first intermediate support 16 having a slot 5 horizontal parallel to the direction of travel. The detection support 15 can be fixed in a desired longitudinal position of said horizontal groove by means of an element of fixation (not shown) inserted through it, and the first intermediate support 16 is fixed to a second intermediate support 17 which has holes in which they are Inserted guide rods 18 fixed to the machine bed. The second

10 intermediate support 17 can be fixed at a selected height of the guide rods 18 by a fixing element (not shown).

The characteristics of the horizontal flexible forming and liner machine of the present invention allow to apply a control method of the cutting device 2 comprising the steps of a) detecting by means of detection means 4 located

15 upstream of the cutting device 2 a plurality of successive detectable elements 21 in the continuous band of preformed containers BP, and b) moving and positioning the cutting device 2 along guide means parallel to said forward direction O by an actuator 5 in response to a positioning signal generated from a detection signal emitted by said detection means 4.

A person skilled in the art will be able to introduce modifications and variations in the exemplary embodiment shown and described without departing from the scope of the present invention as defined in the appended claims.

Claims (14)

1.-Horizontal forming machine and flexible packaging liner, comprising a conveyor device that moves a continuous band of preformed containers (SP) step by step in a forward direction (O), including said continuous band of 5 preformed containers (SP) a plurality of transverse welding lines (ST) defining a plurality of preformed containers (EP), and a cutting device (2) having one or more pairs of cutting blades (3a, 3b) between which the band passes continuum of preformed containers (SP) and cutting drive means that move said cutting blades (3a, 3b) to transversely cut the continuous band of preformed containers 10 (SP) at sites related to said transverse welding lines (ST) and thus forming individual flexible packages (E), characterized in that said cutting device (2) is associated with an automatic cutting correction device comprising detection means (4) located c upstream of the cutting device (2) and arranged to detect a plurality of successive detectable elements (21) in the 15 continuous band of preformed containers (SP), and an actuator (5) operatively connected to move and position the cutting device (2) along guide means parallel to said direction of advance (O) in response to a detection signal emitted by said detection means (4). 2. Machine according to claim 1, characterized in that said detection means (4) 20 include an artificial vision device (7) arranged to capture consecutive images of consecutive portions of the continuous band of preformed containers (SP), each of said consecutive portions including at least one of said detectable elements (21). 3. Machine according to claim 2, characterized in that said detection means (4) 25 further include a lighting device (8) associated with said artificial vision device (7). 4. Machine according to claim 3, characterized in that the cutting device (2) comprises a base support (9) fixed to a machine bed, and a mobile support (10) in which said one or more pairs are installed of cutting blades (3a, 3b) and said 30 cutting drive means, said mobile support (10) being mobile connected to said base support (9) by said guide means. 5. Machine according to claim 4, characterized in that said actuator (5) has a fixed body (5a) fixed to the base support (9) and a mobile element (5b) connected to the mobile support (10), or vice versa. Machine according to claim 5, characterized in that said fixed body (5a) of the actuator (5) comprises an electric servo motor and said mobile element (5b) of the actuator (5) comprises an extensible rod. 7. Machine according to claim 4, characterized in that said guide means comprise a slide (6) fixed to said mobile support (10) Yuno or more sliding guide elements fixed to said base support (9) and mobilely coupled to said slide (6). Machine according to claim 7, characterized in that the slider (6) has converged inclined side surfaces (6a) from top to bottom, and said one or more sliding guide elements comprise rolling elements (13) mounted on the base support (9) and arranged to roll on said inclined side surfaces (6b) of the slide (6). Machine according to claim 4, characterized in that one or more pairs of band guide elements (12a, 12b) between which the continuous band of preformed containers (SP) passes are installed on the mobile support (10), each one in an adjacent position and upstream of one of the one or more pairs of cutting blades (3a, 3b). Machine according to claim 4, characterized in that the cutting drive means comprise a pair of camshafts (11 a, 11 b) parallel to the direction of advance (O) mounted on the base support (9), the which are pivotally rotated by means of actuation, respective cam bars (19a, 19b) connected to said camshafts (11 a, 11 b), corresponding fork yunas (20a, 20b) in solidarity with the leaves of cutting (3a, 3b) of each pair, respectively, coupled to said cam bars (19a, 19b) in a longitudinally sliding manner. 11.-Control method of a cutting device (2) of a horizontal forming machine and flexible packaging liner, where said machine comprises a conveyor device that moves a continuous band of preformed containers (SP) step by step in a direction of feed (O), said continuous band of preformed packages (SP) including a plurality of transverse weld lines (ST) defining a plurality of preformed packages (EP), said cutting device (2) having one or more pairs of sheets of cutting (3a, 3b) between which the continuous band of preformed containers (SP) passes and cutting drive means that move said cutting blades (3a, 3b) to cross-cut the continuous band of preformed containers (SP) at sites related to said transverse welding lines (ST) and thus form individual flexible packages (E), and where the method comprises the steps of: a) detect by means of detection means (4) located upstream of the cutting device (2) a plurality of successive detectable elements (21) in the continuous band of preformed containers (SP); Y b) move and position the cutting device (2) along guide means parallel to said forward direction (O) by means of an actuator (5) in response to a positioning signal generated from an emitted detection signal by said detection means (4). 12. Control method according to claim 11, characterized in that it comprises using an artificial vision device (7) as component of said detection means (7), and that said detection step comprises capturing by means of said artificial vision device (7) ) consecutive images of consecutive portions of the continuous band of preformed containers (SP), where each of said consecutive images includes at least one of said detectable elements (21), and emit said detection signal, which is representative of Consecutive images. 13. Control method according to claim 12, characterized in that it comprises controlling by means of electronic control means the operation of said artificial vision device (7) in accordance with the operation of said conveyor device so that said consecutive images are taken during periods of time in which the continuous band of preformed containers (SP) is stopped between consecutive forward movements of its movement step by step. 14. Control method according to claim 12, characterized in that it comprises using electronic control means to compare the consecutive images taken by the artificial vision device (7) with a predefined image pattern stored in a memory, and generate said signal positioning when a deviation between one of the consecutive images taken by the artificial vision device (7) and said image pattern is detected. or N f "1 w or f "1 or O n OR  Ag.2   D TEA  ST YES   EP ST G ST STSI  Fig. 3 V ......  Fig. 4 D  ... 5e lV \ fifty 5 30 SAW--  12b 3b 12b 3b    120 12b   3b 20b 19b 11b 60 9 190 110 Fig. 6