MEANS FOR FAST GATHERING OF THE COVERING SHEETS

The present invention regards a system for covering crops, comprising a plurality of plastic strips or sheets, suspended over said crops, provided with means for enabling partial gathering of said plastic sheets in order to air said crops.

Crops, in particular grapevines, are usually protected from hail and excessive solar radiation with covers constituted by sheets made of transparent pi asti c materi al .

The supporting structure of said sheets is constituted by a plurality of posts driven into the ground and aligned along the rows, said posts keeping a rope pulled over the top of them. The sheets, which are in the form of strips some metres wide and approximately as long as the row that they cover, are rested in midline on said pulled rope. The strips of the parallel rows are then joined together along the edges with laces and clamps so as to form a continuous cover. The width of the sheets is chosen with a certain excess so as to create a series of sloping stretches that favour draining of rainwater. Finally, the edges are hooked with elastic ropes to hooks driven into the ground to prevent even minor gusts of wind from being sufficient to raise the sheets and cause them to vibrate.

In practice, a sort of sequence of pitched roofings is formed, connected together, with the ropes pulled over the posts that constitute the ridge lines. This cover system, however, limits excessively the air change in the underlying area so that it is periodically necessary to open up the sheets at least partially in order to air the crops.

According to the prior art, this operation is carried out by unlacing the sheets so as to separate the strips and gather said sheets, hooking them to the respective posts. In this way, the cover is not eliminated completely, but wide openings are formed in positions corresponding to the posts, said openings being sufficient to guarantee air change.

The operation of separation of the strips does not present particular problems, it being sufficient to walk along the edges of the strips and unhook the connecting laces. The gathering operation, instead, is not equally convenient, in the first place because the ridge ropes are rather high from the ground and are not easily reachable by persons of small stature, in the second place because these ridge lines are in positions corresponding to the crops so that it is far from convenient also to approach them, and finally because the operation of gathering of the sheet is in any case laborious and then requires tying for the sheet to remain gathered up.

To overcome at least in part the drawbacks described above, in the Italian patent application No. RM2013A000375 , filed in the name of the present applicant, a cover system has been proposed of the type comprising a plurality of sheets or nettings made of plastic material, in the form of parallel strips joined together or set up against one another along the edges and supported by ropes stretched horizontally along the rows, said ropes being supported over the rows by purposely provided posts.

The system according to the invention is characterized in that it envisages means designed to retract in a transverse direction said strips made of transparent plastic material towards their midline in such a way that wide spaces are opened between the strips for airing the underlying crops. These means designed to retract the strips comprise a flexible cord that winds round the strips themselves, said flexible cord forming a loop at each of the posts in such a way that by closing the loop, the cover is gathered up, retracting towards the midline of the strip.

In practice, then, gathering of the sheets for air change is obtained simply by pulling the ropes that hang from each post of each row.

It is evident that this operation must be repeated for all the posts belonging to each row, and this entails that the operation requires a lot of time in so far as one or more persons must reach all the posts of all the rows to stretch out or gather the covering sheets. In many cases, these posts number several hundreds.

In practice, it has, however, been acknowledged that it would be very convenient to have the possibility of gathering the sheet for the entire length of the row, with just one manoeuvre.

Known from EP 2368421 and EP 271207 are systems for covering rows to protect them from hail or from adverse weather conditions, said systems being provided with means for opening the coverings for the entire length of the row, but these patents regard plane covering surfaces, which do not convey rainwater, hail, etc. to the sides of the rows and moreover envisage transverse ropes for supporting the cover, which are not present or necessary in the technical solution forming the subject of the present invention.

The problems cited above are overcome, according to the present invention, starting from the document No. RM2013A000375 , providing - for each row - a continuous longitudinal rope firmly fixed to which are the ends of the ropes or cords that hang from each post .

With such an arrangement, by pulling the continuous rope, gathering of the covering sheet throughout the length of the row will be obtained with just one action.

To stretch the cover out again, it will be sufficient to release the aforesaid rope, and to facilitate return of the sheet into its stretched-out configuration, elastic return means are provided, fixed to the sides of each rope to bring the cover back into its initial conditions of protection.

The invention will now be described according to a preferred embodiment and with reference to the attached figures, in which:

Figure 1 shows the system for covering crops in the case where the sheets are completely stretched out over the rows, in which each row has a winch with self-blocking gear, which can be operated via a crank on one of the end posts, whilst on the other end post a rear winch is preferably provided for recall of the rope with a rewinding spring;

Figure 2 shows the covering sheets of Figure 1 in the closed configuration, i.e., gathered over the supporting posts of the row;

Figure 3, corresponding to Figure 1, shows a variant of the invention in which all the winches on the end posts (or sets thereof) are connected and operated synchronously via a tube that is made to turn by a purposely provided electric motor of adequate power; and

Figure 4 shows an enlarged detail of the invention, visible in which is the system for fixing each return spring for stretching out the sheets again, via a purposely provided ring that is hooked to the edge of the respective sheet as well as to the loop that is used for gathering the sheet at each post when it is desired to uncover the row.

With reference to the figures, the covering system

1 that is described comprises a plurality of posts 2, aligned so as to form one or more substantially rectilinear rows, the top ends of which function as support for arched rods 3, stretched out on which is a sheet 4 preferably made of transparent plastic material (HDPE, Mater-Bi or the like), said sheet being in the form of strips some metres wide and substantially as long as the row.

Covering of the crop is obtained by driving a number of rows of posts 2 into the ground, said rows being appropriately set at a distance apart in such a way that when these sheets 4 are stretched out, a continuous cover is formed.

In practice, the arched rods 3 are of a length such that the side edge of the sheet 4 of one row is adjacent to or at the side edge of the sheet 4 of the contiguous row. According to the prior art, it is also possible to envisage purposely provided laces and clamps for connecting together the side edges of the sheets 4 set side by side.

To favour mounting of the arched rods 3 and their support by the posts 2, there is envisaged the use of post covers 5 appropriately shaped so as to be fitted on the top of said posts 2. The covering is hence constituted by a series of parallel sheets 4 supported in a longitudinal direction by a plurality of pulled ropes 6 and in a transverse direction by said arched rods 3.

When it is desired to carry out air change, it is necessary to reduce the width of said sheets 4 so as to open up wide spaces between two contiguous rows, as illustrated in Figure 2.

For this purpose, at each post 2, a flexible cord is provided set around the sheet 4 so as to form a respective loop 7, in which said loop lies in a plane perpendicular to the pulled rope 6.

The ends 7a-7b of said loop 7 pass through a purposely provided hole or side ring set in the proximity of the post cover 5 in such a way that, by pulling said ends 7a-7b, the loop 7 is tightened around the sheet, gathering it up towards the midline, thus opening up wide spaces to enable airing of the crops .

To restore the initial situation, it is sufficient to release the ends 7a-7b of the loop 7 to stretch the sheets 4 out again.

According to what has been described so far, the current state of the art requires an operator to intervene on each individual post 2, and this involves a lot of work and a lot of time.

To overcome the above drawbacks, the present invention envisages that, for each row, the ends 7a-7b of each loop 7 are firmly fixed to a control rope 8, which is purposely arranged horizontally throughout the length of the row.

It is easy to understand that, by pulling this control rope 8 standing at one end of the row, all the ends 7a-7b of each loop of each post 2 are pulled simultaneously, thus obtaining that the sheet of an entire rope is gathered simply by pulling said rope 8 and without having to act on each post.

According to a peculiar characteristic of the present invention, to facilitate restoring of the cover and stretching-out of the sheet 4, at each loop 7 there are provided two lateral elastic means M, such as two tension springs, designed to widen the loop, and hence stretch out the sheet completely, when the control rope 8 is released and consequently the ends 7a-7b of the loop return into their initial position.

In the preferred embodiment described, these lateral springs M are fixed to the edge of the sheet 4 and preferably to the corresponding loop 7 via a purposely provided ring 15 (see Figure 4), said ring being hooked to the loop 7 and s multaneously fixed to the sheet 4 via a hole purposely provided in the sheet itself, in the proximity of its side edge.

It should be noted that, at the start and end of each row, end posts 9 are provided, one with a winch 10 with self-blocking gear which can be operated via a crank, and the other (optional) with a rear winch 11 for recall of the rope 8 with a rewinding spring.

In the preferred embodiment illustrated in Figures 1 and 2, to reduce friction and render movement of the wires and of the ropes smoother, the ends 7a-7b of the loop 7 run in a winch 14 with clamping mechanism, appropriately fixed to each post 2, substantially at the height at which the horizontal rope 8 is located.

Said front winch 10, in order to pull/loosen the rope 8, is preferably operated manually via a crank with a pawl -and- ratchet mechanism of a known type.

The front winch 10 and the rear winch 11 are preferably mounted on purposely provided end posts 9 appropriately inclined and firmly anchored to the ground to be able to withstand the forces that develop during actuation of the rope 8 to open/close the cover 4.

As an alternative to manual operation of the winch 10 set at the start of each row, a variant of the invention, illustrated in Figure 3, envisages that all the winches 10 (or sets thereof) are connected and operated synchronously via a tube 13 that is made to turn by a purposely provided electric motor 12 of adequate power. In this variant, it is advantageously possible to operate said motor 12 directly to control s multaneously open ng/clos ng of the covering sheets 4 of a series of rows, without it being necessary to intervene on the individual row to gather or stretch out the corresponding sheet 4.

The invention has been described, by way of non- limiting example, according to a preferred embodiment and a variant thereof. The person skilled in the sector will be able to devise numerous other embodiments, without thereby departing from the sphere of protection of the annexed claims.