EP1132299B1 - Machine for packaging a charge having a folding device for a film web - Google Patents

Abstract

The unit is mounted on a horizontal base-plate (1), carrying a roll (2) of wrapping film at one end and a set of guide rollers (9) at the other. The film roll and rollers are of equal height, all the axes being vertical. The film (6) is passed through the rollers, in contact successively with each, and continues to an adjacent wrapping table, on which is placed the article to be packed. This stands upright on a support which is included in the wrapping, the table surface being level with the bottom edge (8) of the film. (The actual wrapping, e.g. by the rotation of the article, is not covered by the invention.) Usually, the distance between the film's top (7) and bottom (8) edges exceeds the height of the article. A guide roller (11), adjustably pivoted on the base-plate edge, is used to fold down the top edge, reducing the effective film width as required. The guide roller has 3 equal sections, rotating about a common spindle held in a bracket (18). This allows differential rotation during the folding-down process. The required inclination is produced by a linear actuator (21), connected between the pivot point and the bracket (23). After wrapping, the film is cut and welded by a terminating unit at the edge of the wrapping table.

Description

The invention relates to machines for packaging loads intended to roll up, to "bandage" say the men of the trade, a film width packaging, generally made of polyethylene, around these charges, since foot to head, to protect them from dust and runoff. These loads are generally placed on pallets.

The packaging is done either by rotating on a platform the load which pulls the film width from a food reel by winding inside, either by rotating an arm which pulls the width of the spool to wrap it around the load. In any case, at the end of the cycle packing, it is necessary to weld and cut the width at the bottom of the load using a cutting and welding clamp device.

Since we want to be able to pack loads of different heights, the cutting and welding device which generally equips machines packaging is suitable for minimum height loads and therefore relatively small height and often smaller than the width of the width wrapping film for food reels. This is why packaging machines are also frequently equipped with a so-called device pleating to adapt and reduce the width of the packaging film by upstream of the cutting and welding device, in the direction of travel of the film width.

We already know devices for pleating machine film width packaging including a frame, two free detour rollers in rotation, mounted to pivot about a central axis of the perpendicular frame to its plan, for, the width of film being slid between the two rollers of the frame, twist, or twist, between two planes inclined one on the other by pivoting the frame and thus forcing the side edges of the width to slide towards each other against the rollers, towards the inside of the frame, in a movement of folding and reduction of width edge to edge.

However, such pleating devices have drawbacks.

First, pivoting the pleating frame requires some travel which increases the size of the machine.

Then, and above all, the lower lateral edge of the width approaching the pivot axis of the frame during pleating and thus being driven upwards, you must be able to lower the pleating device and the spool pin if you really want to be able to weld and cut at the bottom of the load, which is also detrimental in terms of the size of the machine.

The present invention aims to overcome these drawbacks.

To this end, it relates to a packaging machine according to claim 1.

Thus, and thanks to the invention, the height position of the bottom lateral edge of the width of the packaging film not being modified in the device for pleating, cutting and welding of the width at the bottom of the load can be easily insured.

The pleating device has a hinged mounted spreader bar on its foot and means for driving the bar in pivoting on its foot.

By tilting the bar around its foot, its upper part, or its head, deviates from the vertical of his foot, spreading the lateral edge with it top of the film width thus constraining the portion of high width, adjacent to the top side edge, to slide along the spreader bar towards are foot, that is to say down.

Preferably, the spreader bar is mounted to rotate freely on itself.

As the film width continues to run in the pre-stretching device and pleating and that the pivoting of the spreader bar causes a spacing of the progressive film width from the bottom to the top and therefore a web speed gradient around the bar spacing, from the nominal running speed near the foot of bar up to maximum speed at the top side edge, it is advantageous for the spreader bar to have a plurality of independent rotating sections to prevent the upper part of the width does not roll on itself and forms a strand.

Always to best avoid stranding, it is preferable that the spreader bar has, towards its head, friction means intended to exercise relative restraint on the film width, such as example of protrusions, roughness, roughness, raised ridges.

• la figure 1 est une vue en perspective de dessus du dispositif de plissage de la machine,
• la figure 2 est une vue simplifiée de dessus du dispositif de la figure 1,
• la figure 3 est une vue latérale de profil de la barre d'écartement du dispositif de la figure 1,
• la figure 4 est une vue en perspective du dispositif de coupe et de soudage de la machine de l'invention et
• la figure 5 est une vue des mors et contre-mors de coupe et de soudage du dispositif de la figure 4 au cours d'un cycle d'emballage.

The invention will be better understood with the aid of the following description of the preferred embodiment of the machine of the invention, with reference to the appended drawing, in which

• FIG. 1 is a perspective view from above of the pleating device of the machine,
• FIG. 2 is a simplified top view of the device in FIG. 1,
• FIG. 3 is a side profile view of the spreader bar of the device in FIG. 1,
• FIG. 4 is a perspective view of the cutting and welding device of the machine of the invention and
• Figure 5 is a view of the jaws and counter-jaws for cutting and welding of the device of Figure 4 during a packaging cycle.

The machine comprises a frame 1 carrying a food reel 2 of a width of a wrapping film, a platform 3 carrying a support pallet of a load to be packed and, here, rotatably mounted on itself for wrap the width of film around the load and its pallet and, at near the platform 3, a device 4 for cutting and welding the width, which will only be described briefly since it is not concerned by the invention.

Next to the coil 2 is mounted, on the frame 1, a device 5 for pre-stretching and pleating the film width, to reduce the width of the width to the dimensions of the elements of the cutting device and welding 4.

The film width 6 has an initial width equal to the spacing of its two side edges top 7 and bottom 8. Under the action of the rotational drive of the load support platform, the film width 6 is unwound from the reel 2, passes conventionally through a group 9 of pre-stretching rollers and detour of the device 5, axes parallel to that of the coil 2 and protected by a casing 10, before being pleated by the spreader bar 11 of the pre-stretching and pleating device, constituting the pleating part of device 5, also denotes the pleating device.

The spreader bar 11 is made up of rollers, here three 12, 13, 14, mounted end to end but free to rotate on themselves around a rod 15 fixed to the two ears 16, 17 of a wide stirrup 18.

The lower lug 16 is pivotally mounted, about an axis 20, in a fork 19 fixed to the frame 1. The portions of the bar 11 adjacent to the two ears are called foot and bar head, respectively. We assimilate these foot and head of bar to the stirrup ears 16, 17.

It will have been noted that the spreader bar 11 is mounted articulated on the fork 19 to be able to pivot around the axis 20, in this case, of the coil side 2.

On the opposite side, a jack 21 extends along the stirrup 18 mounted articulated around an axis 24, at the lower end of its casing, on a cheek 22 integral with the fork 19 and the frame 1. At its upper end, in fact by the free end of its piston 23, the jack is articulated, around a axis 26, on a transverse bar 25 of the stirrup 18.

Due to the mutual spacing of the articulation axes 20, 24 of the stirrup 18 and of the jack 21, when the jack is actuated, the outlet of the piston 23 out of the cylinder housing forces the stirrup 18, and with it the spreader bar 11, to rotate to follow the increase in the spacing of the two axes articulation 24, 26 of the jack 21, the jack 21 naturally following the stirrup 18 in its pivoting. Note that we can qualify the attachment of the bar 25 to the stirrup 18 and the three articulation axes 20, 24, 26 of articulated polygon. The bar 11 and the jack 21 form this polygon Speak clearly.

The film width 6 passes along the spreader bar 11 on the side where it pivots.

By pivoting the bar 11, the width 6 is pleated, in the sense that its top side edge 7 slides down towards the foot of the bar, its edge lower side 6 remaining substantially at the foot of the bar. There are thus since the head of the bar, by pivoting, deviates from the vertical of the foot, stretch the width, more up than down, and thus constrain the portion of width adjacent to its top lateral edge 7, against the bar head, to slide towards the foot of the bar to compensate for this spacing.

The spacing of the width 6, after pivoting of the bar 11, being progressive from bottom to top, the different longitudinal portions of the width 6 scroll against the bar 11 at different speeds and according to a speed gradient, at nominal speed against the bar foot, at one maximum speed against the helm head. That's why the bar has been "cut" into several 12-14 rollers rotating at different speeds under the action of the width 6, the roller 14 from the top turning the fastest to avoid as best as possible the part high of the width 6 adjacent to the high edge 7 does not roll on itself and forms a strand. In addition, to avoid even better than during the mutual rapprochement of the two lateral edges 7, 8 of the width 6 it does not forms a strand, the "head" roller 14, against which the part scrolls high of the width 6, is provided with circumferential grooves 27 generating friction forces on the width 6 which prevent it from rolling over herself.

At the exit of the pre-stretching and pleating device 5, downstream of the bar of spacing 11 of this device, the width of the width 6 thus pleated is therefore perfectly reduced so that the width, at the end of the packaging cycle, can be gripped between the jaw 28 and the welding counter-jaw 29 and be gripping between the pad 30 and the pinch finger 31 to retain, after the cut, the tail width for the next packaging cycle. We note that the width is cut between the pinch pad 30 and the welding jaw 28.

Claims (7)

1. Load wrapping machine, for winding a width (6), with a top lateral edge (7) and a bottom lateral edge (8), of a wrapping film in a reel (2) around the load, including a reel support (1); means (3) for winding the width (6) around the load, a device (4) for cutting and welding the width and a device (5) for crinkling the width of film (6) including a deviating bar (11) mounted hinged on its foot (16), intended to bring the two lateral edges (7, 8) of the width (6) closer together, which machine is characterised by the fact that the bar (11) is a deviating bar (11) pivotable to a position in which the head of the bar is distant from the vertical to the foot against the width (6), the width of film travelling along the deviating bar on the side to which it pivots and the bringing closer together of the two lateral edges (7, 8) of the width (6) being caused only by the downward sliding of the top lateral edge (7).
2. Wrapping machine as claimed in claim 1, in which drive means to pivot the deviating bar (11) comprise a ram hingedly mounted at the lower end of its casing (21), the free end of its piston (23) being hinged to a small bar (25) on the deviating bar (11).
3. Wrapping machine as claimed in claim 2, in which the articulations (16, 19, 20; 19, 22, 24) of the deviating bar (11) and of the ram casing (21) are spaced apart from each other and the bar (11) and the ram (21) form an articulated polygon.
4. Wrapping machine as claimed in one of claims 1 to 3, in which the deviating bar (11, 12, 13, 14) is mounted to rotate freely about itself.
5. Wrapping machine as claimed in claim 4, in which the deviating bar includes a plurality of sections (12 - 14) which are independent in rotation to prevent the top part of the width (6) from winding on itself and forming a twist.
6. Wrapping machine as claimed in one of claims 1 to 5, in which the deviating bar (11) includes, towards its head (17), friction means (27) intended to apply a relative restraint to the width of film (6).
7. Wrapping machine as claimed in claims 5 and 6, in which the head sections (14) of the deviating bar (11) is a roller provided with circumferential striations (27).

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