FR2703212A1 - Device for digging up and rolling up a plastic film. - Google Patents

Abstract

The invention relates to a device for digging up and winding up a plastic film or a similar material, having a frame (10) mounted on two wheels (11), means for driving and winding (12) said film, means for storage (15) of said wound film, a first rotary spindle (17) disposed essentially transversely to the axis of movement of said device and intended to stretch said freshly dug out film, characterized in that it comprises means (10) for releasing the film still buried, said release means (20) being disposed in front of said device and allowing the means to evacuate part of the vegetation and / or impurities found on said film and hindering the winding thereof.

Description

 Device for digging up and rolling up a plastic film.

 The invention relates to a device for digging up and winding up a plastic film or similar material, at least partially buried in the ground.

 The invention finds its application in particular in the agricultural field where such devices are used in particular for winding films in the form of strips laid on the ground, buried on the edges, and used to allow optimization of irrigation and to preserve crops from harmful elements or organisms. These films are made of flexible materials, such as polyethylene, and generally have a thin thickness which, by letting the solar radiation pass, makes it possible to develop a greenhouse effect and thus to increase the culture temperature.

 These films are thus particularly widely used for conventional crops and in certain specific crops such as the cultivation of asparagus, melons, strawberries, or on vine nurseries, etc. In the context of the laying of such films agricultural plastics on the ground, it can be shaped into mounds forming mulches, which facilitates the wedging of the film on its edges by an adequate burial. The devices for the unwinding and laying of such films are, for this purpose, provided with compacting wheels holding the plastic film pressed to the ground and, behind these wheels, plows making it possible to cover, during their movement, the edges of the deposited film. with sufficient quantities of soil to ensure that the positioning of the film is maintained over time.

Although there are many films which have a certain degree of biodegradability, and which can therefore be left in the ground without it being necessary to recover them when the cultures are completed, certain concerns may lead to the need to recover such films after Among these concerns, we can cite
- the low degree of biodegradability of certain films, the residues of which constitute a source of soil pollution
- the sometimes too long times necessary for the complete disappearance of these films
- the need for certain crops, such as strawberries, to allow during harvesting, obtaining products of a beautiful appearance free of any element such as pieces of plastic film being degraded
- the possibility of recycling the recovered films.

 There already exist in the state of the art devices for digging up and winding up such agricultural films. The method of use implemented by such machines for winding agricultural films consists in drawing the film on which previously harvested crops have been produced and in winding it on a storage reel as the device advances. This film being buried on the edges, these known devices generally include means for removing the earth located on the edges of the film before it arrives on the storage reel.

 Thus, the French patent document FR-2,562,382 describes a device for winding an agricultural film intended to be towed by a motor vehicle comprising a chassis mounted on two wheels driving a reel for storing the wound film, unearthing it edges of the film being effected by two lateral plowshares.

The device described in this patent also has two longitudinal brushes for removing the earth from the edges of the film freshly dug up by the coulters.

Also known in the prior art is a device for unearthing and winding an agricultural film, intended to be coupled to a tractor and having a chassis mounted on two wheels, means for driving and winding the film and a reel storage of it. Such a device also comprises a rotary spindle disposed essentially transversely to the axis of movement of the device and intended to tension the film freshly dug up before it is wound on the reel. Such a device, marketed by the company DL SYSTEM (F-28800, Sancheville) under the trade name
DBE system, also has longitudinal brushes arranged tangentially to said spindle and responsible for removing the earth present on the film, as it passes over the spindle, before being wound on the reel. The spindles used in this machine consist of numerous metallic wires shaped in an arc connected to their ends to form a "squirrel cage" (such spindles are also used in machines to unroll and place agricultural plastic films on the ground and are notably described in French patent application FR-2 235 642).

 The main drawback of the devices known in the prior art lies in the fact that they can only be used when the plants which have grown through such films have either been torn off or cut at their base during the harvest, so as not to hinder the removal of the film. However, for some crops, such as strawberries, the vegetation remaining after harvest is large and dense and makes it absolutely impossible to use such devices.

 These devices of the state of the art also have the disadvantage of not allowing the evacuation of the earth, the vegetation or all the elements found on the film, and in particular at the level of the central strip thereof. Ci, before it is rolled up, that is to say when this film is still on the ground.

Indeed, the existing device using a spindle stretching the film and brushes eliminating the earth when the film passes over the spindle, only allows to clean the film during winding, when it is already lifted from the ground. Such a device must therefore tow the film loaded with soil and convey it thus weighed down to the spindle before the brushes can come into play. In the case of certain cultures, on which there remains a lot of impurities on the film, such only dead leaves, it is then necessary to clean the film before proceeding to wind it.

 The objective of the present invention is to propose a device for digging up and winding up an agricultural film placed on the ground, making it possible to rid this film of the vegetation or impurities which covers it in whole or in part, before or at the time when it is lifted off the ground to allow easier wrapping of this film.

 Yet another objective of the invention is to provide a device which can be used in vine nurseries. In fact, the cultivation of the vines, which is conventionally carried out on mulches covered with a plastic film, requires removing said film when the feet have reached maturity, in order to uproot and select them. Up to now, it was indeed out of the question to mechanize the removal of the films used within the framework of such cultures since the machines available would have risked destroying the vines having to remain planted in the ground and colliding, moreover, to the problem posed by the presence of large quantities of fallen leaves on the films in order to be able to lift them and roll them up.

These objectives, as well as others which will appear subsequently, are achieved by virtue of the invention which relates to a device for digging up and winding up a plastic film or a similar material, having
- a chassis mounted on at least two wheels,
means for driving and winding said film,
means for storing said wound film,
- a rotary spindle arranged essentially transversely to the axis of movement of said device and intended to tension said film before it is wound, characterized in that it comprises means for releasing the film still buried, said disengagement means being disposed in front of said device and making it possible to evacuate at least part of the vegetation and / or impurities present on said film and hampering the winding thereof.

 Such release means positioned in front of the device, come into play when the film has not yet been lifted from the ground by the drive means and remove from the film the vegetation or impurities (soil, dead leaves, etc. ..) found there. The film is thus released and lightened and can be easily rolled up.

 According to a variant of the invention, said means for releasing said film comprise at least one rotary blade mounted so as to be positioned essentially parallel to said still buried film and making it possible to cut at least part of the rooted vegetation through this plastic film. Such release means make it possible to eliminate the plants remaining rooted after the harvest and can for example be used on strawberry, melon crops, etc. during which only the fruits are harvested, the vegetation consisting of the leaves and the rods remaining in place after this operation.

 Although such release means may include only a single rotating blade, these advantageously include at least two rotating blades and leveling means allowing said blades to automatically remain constantly at about the same distance from the ground. In fact, the number of rotary blades can be chosen according to the number of culture lines carried out on said film. In the case where the film is deposited on a perfectly flat surface, the release means will not have to include such means making it possible to automatically maintain the rotary blade or blades at the same distance from the ground.

This distance can be adjusted prior to the use of the device according to the nature of the culture and / or the conformation of the culture soil. On the other hand, as soon as the device must be used to unearth and wind up films placed on surfaces of irregular crops, such means of automatic leveling of the rotary blades will prove to be particularly useful in order not to bite into the film and to do not damage it.

 According to a preferred aspect of the invention, said leveling means consist of a set of two wheels arranged one behind the other essentially parallel to the axis of movement of the device and connected to said chassis by a movable cross member, said set of wheels being mounted on said movable cross member by a pivot joint. The set of wheels thus forms a bogie constantly equalizing the space existing between the blades and the ground.

 According to a particularly interesting aspect of the invention, said device comprises, in addition to the rotary blade or blades, at least one rotary bar positioned essentially perpendicular to said axis of movement of the device and upstream of said blades, said bar being intended to be positioned between the ground and the film and having a polygonal cross section making it possible to shake said film from the start of its winding. Such a bar is particularly useful for removing from the film the creeping vegetation which has not been cut by the rotary blade (s). Such creeping vegetation is found in all stoloniferous plants, such as strawberries or melons.

 Although it may be envisaged to give said rotary bar any polygonal section allowing it to shake the film which will pass over it, this bar will advantageously have a quadrangular cross section or even a triangular cross section.

Furthermore, it will be noted that, the rotary blades rotating at high speed, they will communicate to the freshly cut plants a centrifugal force making it possible to eject them, at least in part, away from the film. However, these blades will advantageously have members for ejecting the cut vegetation.
These ejection members can be formed in the very surface of the blades, essentially perpendicular to the cutting edges of the latter.

 According to another variant of the invention, said release means comprise at least one elongated vibrating element disposed essentially parallel to the axis of movement of the device, the vibrations of said element making it possible to evacuate at least part of the free vegetation and / or impurities present on said film to be wound, while sparing the vegetation rooted through the plastic film. Such release means can be used, when it is necessary to rid the plastic film of its impurities before removing it for winding, but it is impossible to cut the crops which must remain in the ground after the plastic film has been removed. Such a situation appears in particular in vine nursery crops. After the growth of young vine plants has been carried out on soils fitted with plastic films, these are covered with dead leaves which are often wet and therefore heavy. These dead leaves must be removed from the film to facilitate the removal of the latter. The elongated vibrating element according to the invention makes it possible to stir these sheets just before the film is removed and to facilitate their evacuation when the film begins to be wound up by the device.

 Advantageously, said elongated vibrating element forms an angle of about 200 to 60 with the ground. The action of the vibrating element is thus optimized since it has an angle of attack allowing it to take off very effectively the impurities present on the film.

 * Also advantageously, said release means are constituted by a fixed support connected to said chassis by a cross member, by a shaft mounted movable in alternating rotation by a motor essentially parallel to said cross member, and by a vibrating element mounted essentially parallel to said fixed support , at least one connecting rod making it possible to transform, by means of a control lever the alternating rotational movement of said shaft into a reciprocating movement of said vibrating element.

 Preferably, at least two animated deflectors secured to said rotary shaft are arranged on either side of said vibrating element, in a plane essentially parallel to the latter, said animated deflectors making it possible to create a vibration on the buried edges of the plastic film. Such animated deflectors constitute effective means to facilitate the evacuation of the earth and the plant waste present on the plastic film.

 Also advantageously, the device according to the invention comprises at least a second rotary spindle, arranged parallel to said first spindle and between this first spindle and said film release means. The purpose of such a rotary spindle is to serve as a relay in the routing of the film to the storage means thereof.

According to a particularly advantageous variant of the invention, said second rotary spindle is made up of a small number of elements in an arc, so as to favor the vibrations of the film when it passes over said spindle. Thus, it could for example be envisaged to form such spindles with four or six elements in an arc, while the spindles of the state of the art consist of a much higher number of such elements and do not have not to shake the film while it is being rolled up but only to stretch it
Also advantageously, at least one of said first and second rotary spindles is equipped with at least two brushes arranged essentially tangentially to said rotary spindle and making it possible to clean the film passing over it, before it is wound up on said means for storing said film, said film brushes with opposite directions of rotation.

The invention, as well as the various advantages which it presents, will be more easily understood thanks to the description which follows of two nonlimiting exemplary embodiments thereof, with reference to the drawings, in which
- Figures 1 and 2 show a sectional view of two types of cultivation on mounds forming mulches, equipped with a plastic film which can be unearthed and rolled up using a device according to the invention;
- Figure 3 shows a perspective view of a device according to the present invention, which can be used in particular in the context of cultures of the type of that shown in Figure 1;
- Figure 4 shows a detailed view of the release means of the device shown in Figure 3
- Figure 5 shows a perspective view of another device according to the present invention, which can be used in particular in the context of cultures of the type shown in Figure 2
- Figure 6 shows a detailed view of the release means of the device shown in Figure 5
FIGS. 7 and 8 represent two types of spindles which can be used in the context of the devices represented in FIGS. 3 to 6.

 According to Figures 1 and 2, two types of cultivation on earth mounds shaped as mulch are shown in cross section.

 In FIG. 1, a strawberry culture 1 is organized on two culture lines on a mound of earth 2 covered with an agricultural film of polyethylene 3, through which the plans have grown. In order to wedge this film 3 on the mound 2 forming mulch, the edges 4 thereof are covered with earth.

 Two important problems hitherto prevented the use of known devices for recovering agricultural films 3 used in such crops. The first of these problems resides in the fact that, once the strawberries have been harvested, the strawberry plans remain planted (around 2 to 3 years) and spread too far over the agricultural film for one to think of remove it.

 The second of these problems resides in the presence of a creeping vegetation, constituted by the runners 5 of the strawberries which covers the entirety of the film and thus prevents the recovery of the film.

 It should be noted that such runners are not only encountered in the cultivation of strawberries but also in the cultivation of many other so-called stoloniferous plants such as cucurbits (melon, squash, ...).

 With reference to FIG. 2, a vine nursery on a mound of earth 2 covered with a film 3 is also shown diagrammatically in lateral view. The vines 6 cultivated on two parallel lines are represented after their branches have been slightly pruned.

 At this stage of the cultures (generally in December-January), the film 3 must be able to be removed without damaging the vines 6. The main problem which then arises lies in the fact that this film is covered with sheets 7 forming on that -this a mat weighing down the film and making its recovery difficult.

 According to FIG. 3, a device according to the invention which can be used for removing the plastic films used for cultures of the type of that represented in FIG. 1, is shown in perspective.

 This device comprises a frame 10 mounted on two wheels 11. The distance between the wheels 11 is adjustable according to the crops and designed so as to allow the device to pass over the crops without rolling over the mounds themselves. Such a device is intended to be coupled to a tractor. As such, it has coupling means 13.

 This device also comprises means for driving and winding the film constituted by a motor 12 and means for storing the wound film in the form of two cones 15, arranged on the same axis, so that their summits touch each other. These two cones 15 can be rotated by the motor 12 so as to allow the winding of the sampled film and its storage in the form of a reel. Advantageously, the two arms 16 connecting the two cones 15 to the chassis 10 are pivotally mounted on the latter so as to authorize, when the time comes, the removal of the coil formed thereon.

 The device also comprises a rotary spindle 17 disposed transversely to the axis of movement of the device and intended to tension the freshly dug up film. This spindle is formed by a plurality of elements 18 in an arc and constitutes a "squirrel cage".

 Finally, side plowshares 19 are provided to facilitate the digging up of the edges of the agricultural film when it is removed.

 According to the invention, the device comprises, at the front, means 20 for releasing the film still buried. These release means include two rotary circular blades 21 installed symmetrically with respect to the longitudinal axis of the device and each equipped with a motor 22. Each of the blades 21 is intended to cut the vegetation of a crop line. In fact, as can be seen in FIG. 1, strawberry cultures on mulches are conventionally carried out on two lines per film width.

 The means 20 allowing the release of the film from the device shown in Figure 3 are shown in more detail in Figure 4. As can be seen in this figure, the release means 20 are secured to the frame 10 and include means for setting at level 23 of the blades 21 so that the distance existing between them and the ground remains constant. These leveling means 23 therefore allow the rotating blades 21 not to bite the plastic film but only to cut through the vegetation that has grown through it.

These leveling means consist of a set of two wheels 24 arranged one behind the other in the axis of movement of the device and connected to the chassis 10 by an arm 25. The wheels 24 are mounted on a part 27 secured by a pivot joint on the arm 25 via a pin 26. This part 27 accommodates a cross member 28 on which are mounted the two rotary blades 21 and their motors 22, so that the spacing between both blades can be easily adjusted. The part 27 forms with the wheels 24 and the arm 25 a bogie allowing the blades 21 to remain constantly in a plane parallel to the ground determined by the degree of inclination of the wheels 24.

 In order to eject the vegetation cut by the blades 21, these are equipped with ejection members 30 formed essentially perpendicular to the cutting plane and surmounted by plates 29 preventing the cut vegetation from interfering with the action of the motors 22.

 Referring to Figure 3, the device further comprises a rotary bar 31 disposed essentially perpendicular to the axis of movement of the device and upstream of the blades 21. This bar 31 is intended to be positioned between the ground and the film and has a quadrangular section. Its rotation is ensured by a motor 32 and makes it possible to shake the freshly sampled film.

 During the implementation of the device shown in Figures 3 and 4, the release means 20 of the film are implemented before it is lifted and driven by the motor 12 on the spindle 17 and the cones 15. Thus , the blades 21 are actuated to cut the vegetation just before the film is removed. As soon as it begins to leave the ground under the action of the motor 12, the film passes over the vibrating bar 31 which shakes it sufficiently vigorously to evacuate the creeping vegetation present on the film such as the runners. The film then passes over the spindle 17 at the level of which it is stretched before being conveyed to the cones 15 where it is stored in the form of a reel. The oblong shape of the spindle 17 allows the little impurities remaining on the film to be removed when it arrives on this spindle.

 With reference to FIG. 5, another device for digging up and winding up an agricultural film according to the present invention is shown in side view. This device comprises the same basic elements as the device described with reference to FIGS. 3 and 4, namely a chassis 10 having two articulated arms 16 receiving storage means 14 constituted by two cones 15 mounted in opposition and controlled by a motor 12 ; two wheels 11; a time zone 17; coupling means 13; and means 20 for releasing the film which it is desired to unearth and wind up.

 The device shown in Figure 5 can be used to dig up and wind plastic films placed on crops of the type shown in Figure 2, that is to say requiring cleaning of the film prior to removal, while leaving the plants that have grown through this film in the ground. To this end, the film release means positioned in front of the device consist of an elongated vibrating element 41 disposed essentially parallel to the axis of movement of the device. To allow the release of the film, this element 41 has an angle of about 60 with the ground. This vibrating element can thus take off the leaves and the impurities 7 (see FIG. 2) adhering to the film 3 just before the latter is lifted from the ground and transferred to the spindle 17 then wound on the cones 15. The release means 20 of the device also include two animated deflectors 42 arranged on either side of the vibrating element 41, at an adjustable distance from the latter designed to vibrate the film and make it possible to facilitate the passage of the vegetation to be spared during the removal of the film, between the vibrating element 41 and these animated deflectors 42.

 Referring to Figure 6, the release means of the device shown in Figure 5 are shown in detail. These release means 20 comprise a fixed support 45 connected to the chassis 10 of the device by a cross member 43 and a shaft 46 mounted in alternating rotation by a motor 44, essentially parallel to said cross member 43. The motor 44 is mounted on the chassis 10 and actuates the shaft 46 via a villebrequin. Two connecting rods 47 articulated via an axis on the fixed support 45 transmit the alternating rotational movement of the shaft 46 to a vibrating element 41 mounted essentially parallel to said fixed support 45, thanks to a control lever 49. These connecting rods 47 and this control lever 49 make it possible to transform the alternating rotational movement of the shaft 46, instilled by the motor 44, into a reciprocating movement of the vibrating element 41. When the movement of the shaft 46 is very fast, the element 41 vibrates longitudinally. Its end 48 then vibrates the interior surface of the film and peels off the sheets which are glued to it. The animated deflectors 42 which serve as additional means of vibration, considerably assist the passage of the film through the vegetation still in place and evacuate the soil and the leaves on each side of the film.

 When using the device for digging up and winding up an agricultural film according to FIGS. 5 and 6, crops such as the vines pass between the animated deflectors 42 and the vibrating element 41 and are carefully spared by these.

 With reference to FIG. 7, the spindle 17 used both in the device represented in FIG. 3 and in that shown in FIG. 5, can be equipped with two circular brushes 50 having opposite directions of rotation (symbolized by the arrows 51) . These brushes make it possible to remove the few remaining impurities placed on the film after the release means 20 have been used.

 As previously specified, the device for unearthing and winding a plastic film according to the invention may also include an additional rotary spindle 52 disposed between the first rotary spindle 17 and the release means 20 of the device and intended to serve as a relay in transmission of the film to the storage means thereof in the form of a reel. Advantageously, and as shown in FIG. 8, this second rotary spindle 52 may be composed of a small number of elements 18 in an arc, for example 4 or 6. Thus constituted, it will allow during its rotation, to shake the film and to contribute to the evacuation of the impurities still present on it.

 The two embodiments of the invention described here are not intended to limit it. In particular, it could be envisaged to provide the device with release means in numbers adapted to the number of culture lines practiced on the film. It could also be envisaged to design this device not in the form of a coupling but in the form of a self-towing vehicle without departing from the scope of the invention.

Claims (15)

1. Device for unearthing and winding a plastic film (3) or a similar material, having  - a chassis (10) mounted on at least two wheels (11),  - drive and winding means (12) of said film,  - storage means (15) of said rolled film,  - A first rotary spindle (17) disposed essentially transversely to the axis of movement of said device and intended to tension said film (3) before winding, characterized in that it comprises means (20) for releasing the film still buried , said release means (20) being disposed in front of said device and making it possible to evacuate at least part of the vegetation and / or impurities present on said film and hampering the winding thereof. 2. Device according to claim 1 characterized in that said release means (20) of said film comprise at least one rotary blade (21) mounted so as to be positioned essentially parallel to said still buried film and making it possible to cut at least part of the vegetation rooted through said film. 3. Device according to claim 2 characterized in that said release means (20) comprise at least two rotary blades (21) and leveling means (23) allowing said blades (21) to remain automatically constantly at approximately the same distance from the ground. 4. Device according to claim 3 characterized in that said leveling means consist of a set of two wheels (24) arranged one behind the other essentially parallel to said axis of movement and connected to said chassis (10) by a movable cross member (25), said set of wheels being mounted on said movable cross member by a pivot joint (26). 5. Device according to one of claims 2 to 4 characterized in that it comprises at least one rotary bar (31) positioned essentially perpendicular to said axis of movement of the device and upstream of said blades (21), said bar (31) being intended to be positioned between the ground and the film and having a polygonal cross section making it possible to shake said film from the start of its winding. 6. Device according to claim 5 characterized in that said rotary bar (31) has a quadrangular cross section. 7. Device according to claim 5 characterized in that said rotary bar (31) has a triangular cross section. 8. Device according to one of claims 2 to 7 characterized in that said rotary blades (21) have ejection members (30) of the vegetation they cut. 9. Device according to claim 1 characterized in that said release means (20) comprise at least one elongated vibrating element (41) disposed essentially parallel to the axis of movement of the device, the vibrations of said element (41) making it possible to evacuate in particular at least part of the free vegetation and / or impurities (7) present on said film to be wound, while sparing the rooted vegetation (6) through the plastic film (3). 10. Device according to claim 9 characterized in that said elongated vibrating element (41) forms an angle of about 200 to 60 with the ground. 11. Device according to one of claim 9 or 10 characterized in that said release means (20) consist of a fixed support (45) connected to said chassis (10) by a crosspiece (43), by a shaft (46 ) mounted movable in alternating rotation by a motor (44) essentially parallel to said cross-member (43), and by a vibrating element (41) mounted essentially parallel to said fixed support, at least one connecting rod (47) making it possible to transform, thanks to a control lever (49) the alternating rotational movement of said shaft (46) in reciprocating movement of said vibrating element (41). 12. Device according to claim 11 characterized in that at least two animated deflectors (42) secured to said rotary shaft (46) are arranged on either side of said vibrating element (41), in a plane essentially parallel to that- ci, said animated deflectors (42) making it possible to create a vibration on the buried edges of the plastic film. 13. Device according to one of claims 1 to 12 characterized in that it comprises at least a second rotary spindle (52), arranged parallel to said first spindle (17) and between the latter and said release means (20) . 14. Device according to claim 13 characterized in that said second rotary spindle (52) consists of a small number of elements in an arc (18), so as to promote the vibrations of the film during the passage of it- ci on said time zone (52). 15. Device according to one of claims 1 to 14 characterized in that at least one of said first and second rotary spindles (17, 52) is equipped with at least two circular brushes (50) arranged essentially tangentially to said rotary spindle ( 17) and making it possible to clean the film passing over it, before it is wound up on said means for storing said film, said brushes (50) having opposite directions of rotation.