Patent Description:
The present invention has been developed with particular reference to an improved sowing disc.

In automated agriculture, the use of towed or self-propelled agricultural machinery, for distributing material such as, for example, fertilizer or seeds, is known. Precision seeders are known which comprise a plurality of sowing assemblies supported by a frame that rests on the ground by means of at least one wheel and is connected to a tractor for towing the seeder itself.

A sowing assembly comprises at least one distributor device provided with a chamber that has an inlet and an outlet for the seeds to be distributed and that is placed in fluid connection with a fan, mechanically connected to a power take-off of the tractor, for generating a depression inside the chamber itself.

Inside the chamber of the distributor device a distributor element is housed, e.g. a sowing disc, adapted to receive the material due to the effect of the pressure difference and to transport it from the inlet to the outlet of the chamber until it is released into a conveyor conduit that takes it towards the soil onto which it is to be deposited.

Inside the chamber of the distributor device there is also a seed selector element, which is configured to detach from the distributor element an excessive quantity of seeds which, due to the effect of the pressure difference, can adhere to the distributor element and be taken therewith towards the outlet. Such sowing discs, according to the preamble of claim <NUM>, are known from <CIT> and from <CIT>.

Several tests performed by the Applicant have highlighted the need to improve as much as possible the correct distribution of seeds exiting from the distributor device.

Therefore the need has arisen to improve the efficiency of a sowing disc so that it is able to always dispense just one seed at a time regardless of its rotation speed or of the type of seed, the batch of seeds and the environmental parameter values, e.g. humidity and air temperature.

In virtue of the above, an object of the present invention is that of providing a solution to such requirement.

This and other objects are reached through the embodiment of the invention comprising the technical features defined in the main claim. The dependent claims outline preferred and/or particularly advantageous aspects of the invention.

An aspect of the solution according to the present invention provides an improved sowing disc for a granular material distributor device for agricultural machines, comprising:.

wherein each recessed pocket is delimited by at least two side walls and a bottom wall inclined towards the outside of the improved sowing disc.

Thanks to such solution, it is possible to agitate the seed even at high sowing disc rotation speeds without compromising the correct selection of the seed.

The sowing disc according to the invention also comprises:.

Thanks to such solution, an improved sowing disc can be obtained that is compact, easy to manufacture and simple to maintain, which improves the sowing quality of the granular distributor device for agricultural machines.

A further aspect of the present invention provides that said inclined surfaces are depressions provided on the counter-disc.

Thanks to such solution between the counter-disc and a possible drawing member of the improved sowing disc no further surfaces are interposed.

Yet another aspect of the present invention provides that an outer end portion of the inclined surface is convex, an outer end of the crests projecting radially with respect to the central zone of the outer end portion of the inclined surface. Thanks to such solution there is no stagnation zone downstream of each crest, thus the seed can fall into the seed suction zone inside the chamber of the distributor device, without being launched.

A further aspect of the solution according to the present invention provides a granular material distributor device for agricultural machines that comprises an improved sowing disc having the technical features described above.

Yet another aspect of the solution according to the present invention provides an agricultural machine for the distribution of seeds on the soil of the type comprising a granular material distributor device, which comprises an improved sowing disc having the technical features described above.

Further features and advantages of the present invention shall become clearer from the following description, provided by way of example with reference to the appended figures wherein:.

The present embodiment example refers to an improved sowing disc <NUM> for a distributor device <NUM> of a sowing assembly of a precision seeder.

With particular reference to <FIG>, the distributor device <NUM> comprises a case that is internally hollow and defines a chamber inside it. The case is defined by a pair of half-shells <NUM>, <NUM> configured to be joined together for defining the chamber. Each of the two half-shells <NUM>, <NUM> is defined by a substantially concave body and is adapted to be arranged with the concavity facing towards the other half-shell. The half-shell <NUM> comprises a perimeter flange <NUM> adapted to be coupled and fixed through appropriate fixing means, known in themselves, to a perimeter flange of the other half-shell <NUM>.

The half-shell <NUM> further comprises a lower projection adapted to define, in combination with a homologous part of the other half-shell <NUM>, an outlet <NUM> for granular material, i.e. seeds, from the chamber towards the soil.

The half-shell <NUM> further comprises an opening <NUM>, for example realised in a perimeter portion of the half-shell <NUM>, to which an assembly is connected for varying the pressure value inside the chamber.

The improved sowing disc <NUM> according to the present invention comprises a disc <NUM>, preferably but not necessarily made of metal or plastic material, which is housed inside the chamber of the distributor device <NUM> and is particularly adapted for picking material, e.g. seeds, from an inlet of the chamber and for transporting it towards the outlet <NUM> of the chamber of the distributor device <NUM>. The disc <NUM> is rotatably associated with the chamber and in particular is coaxially connected to a rotation shaft <NUM>, connected in turn to transmission means (not illustrated).

The disc <NUM> comprises a central hole particularly adapted to house an end of the rotation shaft <NUM>, and a series of through holes <NUM> arranged circumferentially on the peripheral portion of the disc itself <NUM>. In particular the through holes <NUM> are arranged equidistant from each other and proximal to the edge of the disc <NUM>, and have a smaller diameter than the minimum diameter of the material to be distributed, for example seeds.

The distributor device may further comprise a selector assembly <NUM> also housed in the chamber and adapted to detach from the disc <NUM>, a quantity of granular material, i.e. a number of seeds, transported by the disc <NUM> that exceeds a predetermined threshold quantity. In particular the selector assembly <NUM> is configured to detach from the disc <NUM> the excess seeds with respect to the single seed that each hole <NUM> is configured to bring to the outlet. The selector assembly <NUM> comprises a seed selector element <NUM>, shaped like a substantially flat body, e.g. an elongated plate. The selector element <NUM> is positioned in proximity to a radial end of the disc <NUM> and has a portion overlapping with a radial peripheral portion of the disc <NUM> facing the chamber and external to the holes <NUM>. The selector element <NUM> is hinged, for example at an end thereof, to the half-shell <NUM>.

The distributor device can further comprise a drawing disc (not illustrated) integral in rotation with the rotation shaft <NUM> and comprising, for example, a plurality of engagement elements adapted to engage the improved sowing disc <NUM> and to draw it in rotation together with the drawing disc.

The improved sowing disc <NUM> further comprises a second disc, or counter-disc <NUM>, made of metal or plastic material, fixed coaxial and concentric to the surface of the disc <NUM>. According to this embodiment, the counter-disc <NUM> comprises a central hole <NUM> particularly adapted for housing one end of the rotation shaft <NUM> to which the disc <NUM> is connected, and a plurality of through holes <NUM> to allow the passage of fixing elements, e.g. screws, particularly adapted to fix the counter-disc <NUM> to the disc <NUM>.

The counter-disc <NUM> has a smaller diameter than the diameter of the disc <NUM>, so that the perimeter edge of the counter-disc <NUM> does not overlap with the holes <NUM> of the disc <NUM>, and the holes <NUM> project beyond the perimeter edge of the counter-disc <NUM>.

The counter-disc <NUM> comprises a perimeter peripheral portion on which a plurality of recessed pockets <NUM> are fashioned distributed circumferentially in proximity to the series of through holes <NUM>. Each recessed pocket <NUM> is delimited by at least two side walls <NUM> and a bottom wall <NUM>.

According to a particularly advantageous feature of the present invention, the bottom wall <NUM> is inclined towards the outside of the improved disc <NUM>, so as to be particularly adapted to promote the movement of material, e.g. a seed, towards the holes <NUM> of the disc <NUM>.

According to the embodiments illustrated in the figures, the counter-disc <NUM> comprises a plurality of agitation crests <NUM>, distributed radially and that extend from a central portion of the counter-disc <NUM> towards the outside of the improved disc <NUM>. Each of said agitation crests <NUM> defines the side walls <NUM> of two contiguous recessed pockets <NUM>.

As is more clearly illustrated in <FIG>, the inclined bottom wall <NUM> has a predetermined angle of inclination β with respect to the surface of the disc <NUM>, such that the inner portion of the inclined surface <NUM> has a lower sectional height with respect to the height of an outer end portion <NUM> of the inclined surface <NUM>.

The crests <NUM> can also be realised with an inclined upper surface, so that the outer end <NUM> thereof has a lower sectional height with respect to the height of the inner portion thereof, however greater than the height of the outer end portion <NUM> of the inclined surface <NUM>.

According to a further feature of the present invention, the inclined surfaces <NUM> can be fashioned as radial depressions of the counter-disc <NUM>, so that between the counter-disc <NUM> and a possible drawing member of the improved sowing disc <NUM> no further surfaces are interposed.

According to a particularly advantageous feature of the present invention, and as will be better illustrated in <FIG>, each inclined surface <NUM> connects two pairs of contiguous crests <NUM> in proximity to the outer end <NUM> of each pair of agitation crests <NUM>. In an alternative embodiment, the extension of the outer end portion <NUM> of each agitation crest <NUM> not connected by the inclined surface <NUM> is smaller than the diameter of the hole <NUM> fashioned in the flat perimeter portion <NUM> of the improved disc <NUM>.

According to a further embodiment of the present invention, illustrated in <FIG>, each inclined surface <NUM> connects a pair of contiguous agitation crests <NUM> for the entire longitudinal extension of the agitation crests <NUM>.

According to a further particularly advantageous feature of the present invention, an outer end portion <NUM> of the inclined surface <NUM> may be shaped, preferably convex.

This configuration allows the ends <NUM> of two contiguous crests <NUM> to be arranged at the sides of a through hole <NUM> of the disc <NUM>, and the central zone of the outer end portion <NUM> of the inclined surface <NUM> at a through hole <NUM>, preventing any stagnation zones forming downstream of each crest <NUM>.

According to a further embodiment of the present invention, illustrated in <FIG>, the improved sowing disc <NUM> comprises a disc <NUM>, preferably but not necessarily made of plastic or metal material, which is housed inside the chamber of the distributor device <NUM> and is particularly adapted for picking material, e.g. seeds, from an inlet of the chamber and for transporting it towards the outlet <NUM> of the chamber of the distributor device <NUM>. The disc <NUM> is rotatably associated with the chamber and in particular is coaxially connected to a rotation shaft <NUM>, connected in turn to transmission means (not illustrated).

The disc <NUM> comprises a central hole <NUM> particularly adapted to house an end of the rotation shaft <NUM>, and a series of through holes <NUM> arranged circumferentially on the peripheral portion of the disc itself <NUM>. In particular the through holes <NUM> are arranged equidistant from each other and proximal to the edge of the disc <NUM>, and have a smaller diameter than the minimum diameter of the material to be distributed, for example seeds.

The disc <NUM> further comprises a plurality of recessed pockets <NUM> fashioned on a perimeter peripheral portion of the disc <NUM>. Each recessed pocket <NUM> is delimited by at least two side walls <NUM> and a bottom wall <NUM>.

According to the embodiment illustrated in <FIG>, the side walls <NUM> of two contiguous recessed pockets <NUM> are formed by a crest, an agitation crest <NUM>, elongated towards the outside of the improved disc <NUM>.

According to a further feature of the present invention, the inclined surfaces <NUM> can be fashioned as radial depressions of the disc <NUM>, so that between the disc <NUM> and a possible drawing member of the improved sowing disc <NUM> no further surfaces are interposed.

Naturally, all the technical features and embodiments of the recessed pockets <NUM> described herein are applicable both to recessed pockets <NUM> fashioned directly on the disc <NUM> and to recessed pockets <NUM> fashioned on the counter-disc <NUM> of the improved disc <NUM> of the present invention.

In use, the improved sowing disc <NUM> is placed in rotation inside the distributor device, and the recessed pockets <NUM> agitate the seeds coming from the inlet of the distributor device <NUM> and direct the seeds towards the through holes <NUM> of the disc <NUM> to promote their engagement with one of the holes <NUM>.

Claim 1:
Sowing disc (<NUM>) for a granular material distributor device for agricultural machines, comprising:
- a disc (<NUM>) comprising a series of through holes (<NUM>) arranged circumferentially on the peripheral portion thereof, and
- a plurality of recessed pockets (<NUM>) distributed circumferentially in proximity to the series of through holes (<NUM>), and particularly adapted to agitate the seeds contained inside the distributor device and to direct them towards the through holes (<NUM>), wherein each recessed pocket (<NUM>) is delimited by at least two side walls (<NUM>) and a bottom wall (<NUM>), said bottom wall (<NUM>) being inclined towards the outside of the sowing disc (<NUM>),
characterised in that it further comprises:
- a counter-disc (<NUM>) fixed concentric to the disc (<NUM>) and having a smaller diameter than the diameter of the disc (<NUM>), such that the holes (<NUM>) of the disc (<NUM>) project beyond a perimeter edge of the counter-disc (<NUM>),
- said counter-disc (<NUM>) comprising said plurality of recessed pockets (<NUM>), wherein the counter-disc (<NUM>) comprises a plurality of agitation crests (<NUM>) distributed radially and extending from a central portion of the counter-disc (<NUM>) towards the outside of the sowing disc (<NUM>), each of said agitation crests (<NUM>) defining the side walls (<NUM>) of two contiguous recessed pockets (<NUM>).