Packaging machine

Abstract

A packaging machine has: a winding station (5) for forming a flexible article (2) having an elongated shape into a roll (6); a packing station (7) for winding the stretch film (3) around the roll (6) of flexible articles; a transfer unit (10) for transferring the roll (6) of flexible articles from the winding station (5) to a packaging station (7) at which the roll (6) of flexible articles is intermittently rotated to be wound in the stretch film (3); and a roll changing unit (58) for changing the roll (54) of the stretch film installed in the packing station (7).

Description

[0001] Cross-citation to related applications

[0002] This patent application claims the benefit of Italian Patent Application No. 102024000006451, filed on March 22, 2024, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0003] The present invention relates to a packaging machine for packaging flexible articles having an elongated shape, in particular flexible tubes.

[0004] The invention has particularly advantageous application in packaging flexible tubes in stretch film made of plastic, to which stretch film the following discussion will make explicit reference without loss of generality. Background Art

[0005] In the field of packaging flexible tubes in plastic stretch film, it is known to manufacture a type of packaging machine that includes: a winding station for forming a roll of flexible tube; a feeding unit for feeding a continuous rod of flexible tube to the winding station; a cutting unit for separating the roll from the continuous rod; a packing station for winding the stretch film around the roll; and a conveying unit for conveying the roll from the winding station to the packing station in a forward direction transverse to the longitudinal axis of the roll.

[0006] The packing station includes a wrapping assembly mounted to continuously rotate about a first rotation axis parallel to the forward direction and to wrap stretch film around the roll; and a rotary fixture configured to intermittently rotate the roll about a second rotation axis transverse to the first rotation axis.

[0007] The rotary clamp is equipped with a drive device and a pair of clamping jaws, the drive device being used to move the clamping jaws around the second rotation axis.

[0008] Each clamping jaw includes an outer plate connected to the driving device to move about the second rotation axis; and an inner plate movable relative to the outer plate and parallel to the second rotation axis between a roll clamping position and a roll releasing position.

[0009] For each clamping jaw, the drive device comprises a respective actuating cylinder having an output rod connected to the outer plate of the clamping jaw.

[0010] Since the stretch film is unwound from a stretch film roll mounted on the packaging assembly, known packaging machines of the above type have certain disadvantages, mainly because the replacement of the stretch film roll has to be performed manually by the operator and requires a relatively long and complicated operating sequence and requires downtime of the machine, thereby relatively reducing the productivity of such packaging machines. Summary of the Invention

[0011] The object of the present invention is to provide a packaging machine for packaging flexible articles having an elongated shape, in particular flexible tubes, which does not have the above-mentioned drawbacks.

[0012] According to the present invention, a packaging machine is provided for packaging flexible products with a slender shape, in particular flexible tubes, the packaging machine comprising: a winding station for forming the flexible product with a slender shape into a roll; a packaging station for winding a stretch film around the roll of the flexible product; and a conveying unit for conveying the roll of the flexible product from the winding station to the packaging station in a feeding direction transverse to the longitudinal axis of the roll of the flexible product; the packaging station further comprises: a packaging assembly installed to continuously rotate around a first rotation axis parallel to the feeding direction, and the packaging assembly winds the stretch film around the roll of the flexible product; a first supporting shaft installed on the packaging assembly to receive and hold the first roll of stretch film; and a rotating clamp configured to make the flexible product The roll of sexual products rotates around a second rotation axis transverse to the first rotation axis; it is characterized in that the packaging machine also includes a roll changing unit, which further includes: a storage part, which is provided with at least one second support shaft for receiving and holding the second roll of stretch film, and the storage part can move between a loading position for loading the second roll of stretch film onto the second support shaft and a conveying position for conveying the second roll of stretch film from the second support shaft to the first support shaft; a conveying assembly for disengaging the inner support column of the first roll of stretch film from the first support shaft and conveying the second roll of stretch film from the second support shaft to the first support shaft; and a joining device for connecting the end edge piece of the first roll of stretch film and the starting edge piece of the second roll of stretch film to each other. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The invention will now be described with reference to the accompanying drawings showing non-limiting embodiments of the invention, in which:

[0014] Figure 1 is a schematic perspective view of a preferred embodiment of the packaging machine of the present invention, with some parts removed for clarity;

[0015] Figure 2 and Figure 3 yes Figure 1 Two schematic side views of a packaging machine in FIG, with some parts removed for clarity;

[0016] Figure 4 yes Figure 1 、 Figure 2 and Figure 3 A schematic perspective view of a detail of a packaging machine in FIG, with some parts removed for clarity;

[0017] Figure 5 yes Figure 4 Schematic perspective view of a detail in FIG, with some parts removed for clarity;

[0018] Figure 6 yes Figure 4 and Figure 5 Schematic perspective view of a variation of the detail in FIG, with some parts removed for clarity;

[0019] Figure 7 yes Figure 6 a schematic perspective view of , with some parts removed for clarity; and

[0020] Figures 8a to 8d is shown in four different operating positions Figure 6 Schematic side view of a detail in FIG, with some parts removed for clarity. DETAILED DESCRIPTION

[0021] refer to Figure 1 、 Figure 2 and Figure 3 , reference numeral 1 denotes as a whole a packaging machine for packaging a flexible tube 2 in a stretch film 3 made of plastic.

[0022] The machine 1 comprises an elongated base 4, a winding station 5 of known type for forming a roll 6 of the tube 2, a packing station 7 for winding the film 3 around the roll 6, a feed unit 8 of known type for feeding a continuous rod 9 of the tube 2 from an extrusion unit (not shown) to the station 5, and a transfer unit 10 for transferring the roll 6 from one station 5 to another station 7 in a horizontal direction of advance 11 transverse to the longitudinal axis 12 of the roll 6.

[0023] The station 5 is equipped with a wrapper roller 13 of known type, mounted to rotate about its own longitudinal axis 14, which is parallel to a horizontal direction 15 transverse to the direction 11, and which is also mounted to move linearly in the direction 15 between a forward position for forming the roll 6 and a withdrawn position for disengaging the roll 6.

[0024] The roller 13 is delimited by an outer wall 16 extending around the axis 14 and by a plurality of flat or cylindrical support segments (not shown) which are movable transversely to the axis 14 between an expanded position for forming the roll 6 and a retracted position for disengaging from the roll 6.

[0025] The feeding unit 8 comprises a first horizontal slide 17 slidably coupled to the base 4 to perform a linear movement relative to the base 4 in the direction 15 and supporting an inlet cone 18 configured to receive the rod 9 of the tube 2 .

[0026] The unit 8 also includes a second horizontal slide 20 which is slidably connected to the slide 17 to perform a linear movement relative to the slide 17 parallel to the direction 11 and which supports a slender guide arm 21 which protrudes from the slide 20 in the direction 11 to release the tube 2 on the roller 13.

[0027] The slide 17 also supports a cutting device 22 configured to separate the roll 6 from the rod 9 at the end of a roll 6 forming cycle on the roller 13 .

[0028] The unit 8 is moved in the direction 15 by means of a slide 17 so that the tubes 2 are correctly and evenly distributed along the axis 14 and then onto the rollers 13 .

[0029] The transfer unit 10 includes: a horizontal slide 23, connected to the base 4, for performing a linear motion along the direction 11 between the station 5 and the station 7 relative to the base 4 itself; a vertical slide 24, connected to the slide 23, for performing a linear motion in a vertical direction 25 orthogonal to the directions 11 and 15 relative to the slide 23 itself; and an inclined slide 26, connected to the slide 24, for performing a linear motion in a direction 27 inclined relative to the directions 11 and 25 relative to the slide 24 itself.

[0030] The slide 24 supports a lower support 28 which defines a substantially horizontal support plane P1 for the roll 6, and a rear plate 29 which defines a substantially vertical support plane P2 for the roll 6 and extends perpendicular to the direction 11, and which is slidably connected to the slide 26 so as to perform a linear movement relative to the support 28 in the direction 11 according to the diameter of the roll 6 during the setting phase of the transport unit 10.

[0031] Preferably, but not necessarily, the plate 29 is moved along the slide 26 in the direction 11 by drive means (not shown) comprising an electric motor having an output shaft connected to the plate 29 .

[0032] At the packing station 7 , the rolls 6 are advanced and released by the transfer unit 10 in a receiving channel 30 defined by two parallel side walls 31 , each having a sector shape perpendicular to the direction 15 and also having an angular width less than 180°.

[0033] The channel 30 can be moved between a forward position and a retracted position along the direction 11 under the thrust of a known actuating cylinder (not shown), and cooperates with a terminal stroke rod 32, which is installed between walls 31 parallel to the direction 15 and is slidably connected to the walls 31 to perform a linear movement parallel to the direction 11 relative to the walls 31.

[0034] like Figure 4 and Figure 5 As shown, during the setting phase of the packaging station 7, the position of the rod 32 relative to the wall 31 is selectively controlled, depending on the diameter of the roll 6, by a drive device 34 comprising an electric motor 35, the output shaft of which is coupled via a belt drive 36 to a screw 37 extending parallel to the direction 11 and to the rod 32 via a screw-screw coupling.

[0035] The passage 30 is aligned with a rotary clamp 38 mounted upstream of the passage 30 in direction 11 and comprising two clamping jaws 39 mounted to rotate alternately about an axis of rotation 40 parallel to direction 15 .

[0036] Each claw 39 has a sector shape perpendicular to direction 15 and further has an angular width of less than 180°. Each claw 39 also includes an outer plate 41 mounted for rotation about axis 40; and an inner plate 42 coupled to plate 41 in an angularly fixed manner for rotation about axis 40 and slidably movable relative to plate 41 in a linear manner along direction 15 between a roll-holding position and a roll-releasing position.

[0037] The jaw 39 is moved about the axis 40 by drive means 43 comprising an electric motor 44 connected to a transmission shaft 45 via the interposition of a gear reducer 46 .

[0038] A shaft 45 is mounted to rotate alternately about its own longitudinal axis 47 parallel to the direction 15 and is connected to the plate 41 of each jaw 39 via a relative crank mechanism 48 .

[0039] Each crank mechanism 48 includes a crank 49 coupled to the shaft 45 in an angularly fixed manner, and a connecting rod 50 rotatably coupled to the crank 49 on one side and to the plate 41 of the corresponding claw 39 on the other side.

[0040] The shaft 45 has at least one telescopic section 51 axially movable along the axis 47 to allow selectively varying the distance between the jaws 39 as a function of the width of the roll 6 measured parallel to the direction 15 when the clamp 38 is set.

[0041] The packing station 7 is also provided with a packaging assembly 52 of known type comprising a rotating arm 53 having an L-shape, supporting at least one roll 54 of film 3 and mounted to rotate continuously around an axis of rotation 55 parallel to the direction 11 under the thrust of an electric motor 56 .

[0042] When the containing channel 30 is arranged in its retracted position, the arm 53 is moved by the motor 56 about the axis 55 in order to wind the film 3 around the roll 6 .

[0043] The packaging machine 1 further comprises an electronic control unit 57 which is connected to the electric motors 44 and 56 and is configured to:

[0044] Synchronizing and phasing the motor 56 of the arm 53 and the motor 44 of the gripper 38 with each other;

[0045] selectively controlling the operation of the motor 44 of the clamp 38 to move the shaft 45 in a reciprocating rotational motion about an axis 47;

[0046] selectively controlling the operation of the motor 44 of the clamp 38 and, therefore, the rotation of the jaws 39 according to the diameter of the roll 6; and

[0047] The operation of the motor 44 of the clamp 38 , and therefore the rotation of the jaws 39 , is selectively controlled to cover the entire web 6 with a relatively small number of layers of film 3 .

[0048] The operation of the packaging machine 1 will now be described starting from when the roll 6 of tube 2 is separated from the rod 9 of tube 2 by the cutting device 22, the receiving channel 30 is arranged in its forward position and the gripping jaws 39 of the rotating clamp 38 are arranged in their release position.

[0049] The vertical slide 24 and the inclined slide 26 of the transfer unit 10 are raised to allow the lower support 28 and the rear plate 29 to engage the roll 6, and the horizontal slide 23 of the transfer unit 10 advances in direction 11 to move the roll 6 from the winding station 5 to the packaging station 7 and into the receiving channel 30.

[0050] At this time, the clamping claws 39 of the rotating clamp 38 move to their clamping positions to hold the roll 6 , and the receiving channel 30 moves to its retracted position.

[0051] Moving the containment channel 30 to its retracted position allows the rotating arm 53 of the packaging assembly 52 to rotate about the axis 55 and wind the film 3 around the web 6 .

[0052] During the wrapping of the film 3 around the roll 6 , the roll 6 is intermittently rotated about the axis 40 by the clamp 38 to allow the packaging assembly 52 to wrap the entire roll 6 with the film 3 .

[0053] The packaging machine 1 has certain advantages which arise mainly from the fact that the gripping jaws 39 of the rotary clamp 38 are driven by drive means 43 , ie by a single drive means, ensuring proper synchronization of the movements of the jaws 39 about the axis 40 and uniform winding of the continuous web 6 .

[0054] Furthermore, the electric motor 44 of the drive 43 enables the electronic control unit 57 to synchronize and phase the electric motor 56 of the arm 53 and the electric motor 44 of the gripper 38 with each other so as to:

[0055] selectively controlling the rotation of the web 6 about the axis 40 according to the size of the web 6 and the number of layers of film 3 applied to the web 6;

[0056] ensuring that the packaging machine 1 has a relatively high productivity and a relatively low consumption of the film 3; and

[0057] Stopping the packaging machine 1 to set it up is avoided.

[0058] Figure 6 、 Figure 7 The variation shown in FIG8 differs from the variation shown in the aforementioned figures in that the packaging machine 1 further comprises a roll changing unit 58 configured to replace the roll 54 mounted on a support shaft 59 extending from the rotating arm 53 parallel to the direction 11 and the axis 55.

[0059] Unit 58 comprises: a horizontal guide 60 mounted on the base 4 parallel to direction 15; and a first horizontal slide 61 slidably connected to the guide 60 to perform a linear movement along direction 15 relative to the base 4 and under the thrust of an actuator cylinder 62 between the base 4 and the slide 61.

[0060] The slide 61 comprises a box-like body 63 which is cup-shaped with a recess facing upwards and is provided with a support shaft 64 which extends in the direction 11 and supports a new roll 65 .

[0061] The body 63 supports a second horizontal slide 66 slidably coupled to the body 63 to perform linear motion in the direction 11 relative to the body 63 and under the thrust of an actuator cylinder 67 interposed between the slides 61 and 66 .

[0062] The slide 66 is provided with a drive member 68 which extends around the shaft 64 and is movable along the shaft 64 under the thrust of a cylinder 67 to disengage the roll 65 from the shaft 64 .

[0063] The slide 66 supports a clamping device 69 that can be moved between a clamping position and a release position of the starting flap of the roll 65, and the slide also supports a connecting device 70 that is configured to connect the starting flap of the roll 65 and the end flap of the roll 54 to each other according to an operating mode (which will be discussed further below).

[0064] In addition, the rotating arm 53 of the packaging assembly 52 supports: a clamping device 71, which is configured to hold the end edge piece of the roll 54 by suction; a cutting device 72, which is used to separate the end edge piece of the roll 54 from the roll 54 itself; and a thrust member 73, which extends around the shaft 59 and can be moved along the shaft 59 under the thrust of the actuator cylinder 74 to disengage the inner support column 75 of the roll 54 from the shaft 59.

[0065] Now refer to Figure 6 、 Figure 7 8 describe the operation of the unit 58 and begins when the slide 61 is moved by the actuator cylinder 62 from a retracted position, in which the shaft 64 is aligned with the shaft 59 in the direction 11, to a forward position in which the person in charge loads the roll 65 onto the shaft 64.

[0066] In this regard, it should be noted that the shaft 64 is provided with at least one locking member (not shown) which is radially movable between a locking position of the roll 65 on the shaft 64 and a release position in which the roll 65 is released from the shaft 64 .

[0067] The consumption of the web 54 of film 3 is controlled by detection means 76 , in particular sensors, mounted on the arm 53 .

[0068] After the roll 54 is exhausted, the arm 53 and therefore the shaft 59 stop in a given angular position about the axis 55 in response to signals from the device 76 and from detection means 77 of the angular position of the arm 53 about the axis 55 , in particular a sensor.

[0069] The terminal edge piece of the film 3 of the roll 54 is locked and held on the surface of the clamping device 71 by suction, and the terminal edge piece is separated from the roll 54 by the cutting device 72.

[0070] Slide 61 is now moved by cylinder 62 to an intermediate position between the retracted and forward positions to allow cylinder 74 to advance thrust member 73 along shaft 59 and disengage inner support cylinder 75 of roll 54 from shaft 59 and into body 63 .

[0071] The slide 61 is then moved to its retracted position to align the shafts 59 and 64 with each other in direction 11 and to allow the cylinder 67 to move the slide 66 in direction 11, allowing the roll 65 to disengage from the shaft 64 and move onto the shaft 59, allowing the clamping devices 69, 71 and the coupling device 70 to be arranged in the same receiving plane perpendicular to the direction 11, and allowing the starting edge piece of the film 3 of the roll 65 held by the device 69 to overlap with the end edge piece of the film 3 of the roll 54 held by the device 71.

[0072] In this regard, it should be noted that the shaft 59 is provided with at least one locking member (not shown) which is radially movable between a locked position of the rolls 54, 65 on the shaft 59 and a released position in which the inner support cylinder 75 of the rolls 54, 65 is released from the shaft 59.

[0073] At this point, the end edge piece of the membrane 3 of the roll 54 and the starting edge piece of the membrane 3 of the roll 65 are connected to each other by the coupling device 70; the clamping devices 69, 71 are moved to their release positions; and the slide 61 is moved again from its retracted position to its forward position to allow the operator to load a new roll 65 onto the shaft 64.

[0074] Thus, the unit 58 is able to automatically replace the roll 54 mounted on the shaft 59 with a new roll 65. This replacement is carried out during idle time in the production cycle, without requiring the packaging machine 1 to stop and without requiring human intervention to load the roll 65 onto the shaft 64.

[0075] According to a variant not shown, the slide 61 is eliminated and replaced by a rotating platform configured to support a plurality of rolls 65 distributed along its peripheral edge and rotating about an axis of rotation parallel to the direction 11 .

Claims

1. A packaging machine for packaging flexible articles (2) having an elongated shape, in particular flexible tubes, comprising: a winding station (5) for forming the flexible product (2) having an elongated shape into a roll (6); a packing station (7) for winding a stretch film (3) around the roll (6) of flexible product; and a transfer unit (10) for transferring the roll (6) of flexible product from the winding station (5) to the packing station (7) in a feed direction (11) transverse to the longitudinal axis (12) of the roll (6) of flexible product; The packing station (7) further comprises: a packaging assembly (52) mounted to continuously rotate around a first rotation axis (55) parallel to the feeding direction (11), and the packaging assembly wraps the stretch film (3) around the roll (6) of the flexible product; a first support shaft (59) mounted on the packaging assembly (52) to receive and hold the first roll of stretch film (54); and a rotating clamp (38) configured to rotate the roll (6) of the flexible product around a second rotation axis (40) transverse to the first rotation axis (55); characterized in that the packaging machine further comprises a roll changing unit (58), which further comprises: a storage portion (63) provided with at least one second support shaft (64) for receiving and holding A second roll of stretch film (65), and the storage portion is movable between a loading position for loading the second roll of stretch film (65) onto the second support shaft (64) and a transfer position for transferring the second roll of stretch film (65) from the second support shaft (64) to the first support shaft (59); a transfer assembly (66, 68, 73) for disengaging the inner support column (75) of the first roll of stretch film (54) from the first support shaft (59) and transferring the second roll of stretch film (65) from the second support shaft (64) to the first support shaft (59); and a joining device (70) for connecting the end edge piece of the first roll of stretch film (54) and the starting edge piece of the second roll of stretch film (65) to each other.

2. The packaging machine according to claim 1, wherein: The conveying assembly (66, 68, 73) includes: a first conveying device (73), installed on the packaging assembly (52) to disengage the inner support column (75) of the first roll of stretch film (54) from the first support shaft (59); and a second conveying device (66, 68), installed on the storage part (63) to convey the second roll of stretch film (65) from the second support shaft (64) to the first support shaft (59).

3. The packaging machine according to claim 2, wherein: The engaging device (70) is mounted on the second conveying device (66, 68).

4. The packaging machine according to claim 2 or 3, wherein: The roll changing unit (58) further comprises: a first clamping device (71) for holding the end edge piece of the first roll of stretch film (54); and a second clamping device (69) for holding the starting edge piece of the second roll of stretch film (65).

5. The packaging machine according to claim 4, wherein: The first clamping device (71) is mounted on the packaging assembly (52), and the second clamping device (69) is mounted on the second conveying device (66, 68).

6. The packaging machine according to claim 4 or 5, wherein: The second conveying device (66, 68) can move between a stationary position and an operating position parallel to the longitudinal axis of the second roll of stretch film (65), in which the second roll of stretch film (65) is conveyed from the second support shaft (64) to the first support shaft (59), and the first clamping device (71) and the second clamping device (69) themselves are arranged in the same accommodating plane perpendicular to the longitudinal axis of the second roll of stretch film (65) so that the end edge piece of the first roll of stretch film (54) overlaps with the starting edge piece of the second roll of stretch film (65).

7. The packaging machine according to claim 6, wherein: After the second conveying device (66, 68) is moved to the operating position, the joining device (70) arranges itself in the receiving plane to connect the end edge piece of the first roll of stretch film (54) and the starting edge piece of the second roll of stretch film (65) to each other.

8. Packaging machine according to any one of the preceding claims, wherein The roll changing unit (58) further comprises a first detection device (77) for detecting the position of the packaging assembly (52) around the first rotation axis (55).

9. Packaging machine according to any one of the preceding claims, wherein The roll changing unit (58) further comprises a second detection device (76) for detecting consumption of the first roll of stretch film (54) on the first support shaft (59).

10. Packaging machine according to any one of the preceding claims, wherein The storage portion (63) is movable to an intermediate position disposed between the loading position and the transfer position to receive the inner support column (75) of the first roll of stretch film (54) detached from the first support shaft (59) by the transfer assembly (66, 68, 73).

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