Patent Description:
In agriculture, devices for distributing and burying solid granular products such as fertilizers, corrective agents, soil improvers, geodisinfestants, pesticides, etc. are known. They are generally applied to ploughing machines or the like, which can be self-propelled or towed by tractors and include a plurality of "anchors", arranged side by side to form one or more rows and configured to penetrate the ground so that with the advancement of the machine can perform a plurality of parallel grooves of the desired depth and of limited width.

The known devices for distributing and burying granular products, to be applied to subsoiler machines or the like, comprise a plurality of rigid tubular ducts which are applied behind each anchor and have the upper end connected through a flexible duct to an overlying tank containing the granular product to be distributed and buried, and the lower end which, during the work of the machine, opens to the desired depth in the ground, immediately behind the respective anchor, so that as the machine advances in the ground and the various anchors form the grooves in this, within each groove just formed the predetermined quantity of granular product is dispensed, which is then covered by the soil previously locally removed from the anchor.

The tank containing the granular product to be distributed can also be mounted in front of the tractor and in this case the product is transported by a pneumatic system to the flexible ducts that feed the rigid tubular ducts located behind the anchors.

A ploughing machine of this type is described in <CIT>. It is equipped with a device for distributing and burying fertilizers, and includes a frame, to which a plurality of anchors spaced transversely and equipped with hydraulic jacks are articulated, which have the dual function of individually adjusting the inclination of the anchors with respect to the ground and to cushion any small oscillations that may arise during the work of the machine. Each anchor is associated with a fertilizer dispensing unit, with a duct placed behind the anchor itself and adjustable in height similarly to this one but independently of this to reach the correct working position, especially when ploughing the soil along longitudinal strips. In this case, in fact, it may happen that these longitudinal bands have different characteristics either due to the nature of the ground or because they are subjected to different stresses. It is not infrequent, in fact, the case of soils that in the previous year or also during the current tillage operations present certain longitudinal bands affected by the passage of the wheels of the operating machines which are more compact than the longitudinal bands not affected by this passage. For this reason it is suggested to adjust the depth of introduction of the fertilizer into the soil to overcome any compacted layer.

A problem that is often encountered in the use of known distribution and burying devices for solid granular products consists in the fact that the subsoiler machines, to which they are applied, very often have to operate with anchors at depths of even <NUM>-<NUM> and beyond, that is, at depths at which stones of considerable size, roots or other obstacles of difficult and sometimes practically impossible removal, can be found.

In order to avoid damage that can occur if an anchor of the ploughing machine encounters a large buried stone or in any case an obstacle of similar characteristics, it has already been proposed to mount each anchor on the frame of the machine by means of a pivot pin and preventing its rotation around said pin by means of controlled yielding.

These controlled yielding means can be constituted for example by a bolt which blocks the rotation of the anchor but which, upon exceeding a predetermined stress, yields to traction or shear, or they can be constituted by a spring or a fluid-dynamic cylinder, which in normal conditions counteracts the failure of a locking member of the anchor in the operative position but which yields when a predetermined amount of stress is exceeded and allows the total overturning backwards of the anchor to overcome the obstacle without causing any damage or breakage of the ploughing machine.

However, if a duct for dispensing the granular product to be buried is associated with an anchor, tilting the anchor backwards can irreparably damage the dispensing duct for the granular product, which is generally rigid; and while the controlled yielding means are designed to be quickly restored to their functionality, the delivery duct that has been damaged requires its disassembly from the machine, its replacement and the restoration of its connection with the supply duct coming from the tank of granular products.

The purpose of the invention is to eliminate this drawback and to propose a device for the distribution and burying of solid granular products, which is applicable to an anchor of a subsoiler and which does not suffer consequences in the event of its impact, during the distribution of the granular product, against an underground obstacle.

Another object of the invention is to propose a device which allows to simultaneously distribute and bury solid granular products even at different depths in the ground.

Another object of the invention is to propose a device which, when it has to distribute solid granular products at different depths, ensures a substantial uniformity of distribution at any depth.

Another object of the invention is to propose a device for distributing and burying solid granular products which can be easily restored in its functionality together with the respective anchor.

Another object of the invention is to propose a device for distributing and burying solid granular products which can be automatically restored in its functionality.

Another object of the invention is to propose a device for distributing and burying solid products which is simple and reliable in operation.

Another object of the invention is to propose a device for distributing and burying solid granular products which can be practically applied to any subsoiler equipped with anchors.

All these objects and others that will result from the following description are jointly or separately achieved according to the invention with a device for the distribution and burial of solid granular products as defined in claim <NUM>.

The present invention is further clarified hereinafter in some of its preferred embodiments reported for purely illustrative and non-limiting purposes with reference to the attached drawing tables in which:.

As can be seen from the figures, the device according to the invention for distributing and burying solid granular products finds application, for example, in soil ploughing machines or the like, and in particular in a ploughing machine <NUM>, illustrated in <FIG>, to be hooked to a tractor (not shown) for its movement in the soil to be treated.

The particular ploughing machine shown may for example present two transversal rows of anchors <NUM>, a more advanced one formed by three anchors transversely placed side by side and spaced apart, and a more rearward formed by four staggered anchors with respect to those of the most advanced row, in so as to form seven parallel and equidistant depth grooves in the ground during the work phase, linked to the extent of the portion of anchor introduced into the ground. However, all this is well known to the skilled person and is described here essentially to contextualize the invention.

The frame <NUM> of the machine, which supports two transversal bars <NUM>, to which the seven anchors <NUM> are constrained, also supports one or more tanks <NUM> for containing the solid granular products <NUM> to be distributed in the ground. In some cases a single tank is sufficient, but in other cases it is preferable to have several tanks containing the same product or different products, which are traditional in themselves and can consist of fertilizers, corrective agents, fertilizers, soil improvers, geodisinfestants, of pesticides, etc. or of mixtures of these.

The tank <NUM> is provided at the bottom with connections <NUM> for ducts <NUM> for feeding the granular products <NUM> to the individual distribution and burial units applied to each of the anchors <NUM>.

The solid granular product to be distributed flows through the ducts <NUM> by gravity or pushed by a pneumatic system of the machine.

Preferably, each connection <NUM> is provided with a product <NUM> interception gate, which can be controlled manually or mechanically in a traditional manner.

In the embodiment illustrated in <FIG> each anchor <NUM> comprises an upper fork support <NUM>, for attachment to a bar <NUM> of the frame <NUM> of the ploughing machine <NUM>, and a leg <NUM>, which is articulated to the support <NUM> at a transverse pin <NUM>, has an elongated shape and is provided at the bottom with a shaped tip <NUM> so as to be able to easily penetrate the ground as the machine advances.

The leg <NUM> is kept with the tip <NUM> in the most advanced position, which is the working position, by a bolt <NUM>, which adheres to an upper appendage <NUM>, of which the leg <NUM> is provided (<FIG>,<FIG>), to an abutment element <NUM>, integral with the fork support <NUM>.

The diameter of the bolt <NUM> is chosen so as to break when a predetermined amount of the tensile stress is exceeded, which arises when the leg <NUM> encounters an underground obstacle, which tends to overturn it backwards in the direction of the arrow <NUM> in <FIG>.

Of course, this eventuality must be considered exceptional and involves stopping the machine and replacing the bolt <NUM>, even if different ways of controlling the backward overturning of the leg <NUM> of the anchor <NUM> and these are not described here, as they are known by itself.

An attachment <NUM> is applied to the fork support <NUM> of each anchor <NUM> or, alternatively, to the frame <NUM> of the machine, for the lower end of the duct <NUM> for feeding the granular product <NUM> to that anchor, and generally this lower attachment comprises an upper cylindrical portion <NUM> for insertion of the lower end of the duct <NUM>, which is preferably constituted by a substantially rigid or semi-rigid plastic tube, and also comprises a lower head <NUM>, which in working condition extends upwards a duct <NUM>, preferably with a rectangular section, intended to run behind the leg <NUM> of the anchor <NUM> when this is placed in working condition (<FIG>).

The rigid head <NUM> of the attachment <NUM> is preferably constrained to a guide element <NUM> of the duct <NUM>, as will be better described hereinafter.

This guide element <NUM>, if present, is fixed to the fork support <NUM> or to the frame <NUM> of the machine and can be, for example, made up of two parallel bars <NUM>, which are spaced apart to an extent suitable to allow the free sliding of the duct <NUM> between these, they extend backwards and are connected at their rear end by a transverse bar <NUM>.

A further transverse bar <NUM> is applied to the upper end of the duct <NUM> longer than the distance between the two bars <NUM> of the guide element <NUM>, so as to prevent the complete disengagement of the duct <NUM> from the guide element <NUM> and to define the correct position of the upper end of the duct <NUM> in the working condition, that is, the position exactly facing the rigid head <NUM>. For this purpose it is foreseen that in each of the two bars <NUM> a depression <NUM> can be obtained, which is engageable by the further transversal bar <NUM> to maintain the upper end of the duct <NUM> in contact with the rigid head <NUM> in order to create a continuity between the two for a correct passage of the granular product from one to the other.

The lower end of the duct <NUM> is articulated at a pin <NUM> to a pair of side-by-side plates <NUM>, fixed to the leg <NUM>.

The device according to the invention also provides that between the attachment <NUM> of the duct <NUM> for feeding the granular product and the upper end of the duct <NUM> can advantageously be interposed with one or more springs <NUM>, which have the function of keeping the head <NUM> of the attachment <NUM> and the upper end of the duct <NUM> coupled together, but at the same time allowing both their spacing caused by external causes, and in particular the overturning backwards of the corresponding anchor <NUM>, as will be seen better below, and their elastic re-coupling when they cease. For this purpose it is advantageous if the cooperating ends of the head <NUM> and of the duct <NUM> are cut according to an inclined plane or in any case according to the desired complementary pattern which ensures both their precise mating in coupled condition and their easy uncoupling.

The operation of the device according to the invention in this embodiment is as follows:
in normal working conditions, the ploughing machine <NUM> advances into the ground by itself or, in the case exemplified, pulled by a tractor, and has all the anchors <NUM> inserted with their tip <NUM> and with the lower part of their leg <NUM> in the ground at the depth determined by the characteristics of the machine and the required working depth.

As the machine advances, the anchors <NUM> create corresponding grooves, into which the solid granular product <NUM>, which comes from the tank <NUM>, through the feed ducts <NUM>, the rigid head <NUM> can fall by gravity or pushed by the pneumatic system of the machine of the respective attachments <NUM> and the ducts <NUM>. Immediately after the passage of the anchors <NUM>, the respective grooves created by them close again.

If one of the anchors <NUM> accidentally encounters an obstacle that it cannot remove, for example a large buried stone, the stress it receives due to the contrast between the tip <NUM>, which cannot advance due to the presence of the obstacle and the upper part of the leg <NUM>, which is dragged forwards, causes a traction on the bolt <NUM> which keeps the anchor in operating condition, and if this stress exceeds a predefined value, it causes the bolt <NUM> to break and the consequent backwards turn of the tip <NUM> and of the lower part of the leg <NUM> around the pin <NUM> for articulation to the fork support <NUM>.

Following this overturning, the duct <NUM> remains articulated with its lower end to the pin <NUM> and decouples with its upper end from the head <NUM>, while remaining in the same vertical plane, thanks to the guide element <NUM> (<FIG>), if provided, or thanks to the combined effect of the springs <NUM> and the pin <NUM>.

Evidently and in this phase the springs <NUM> yield and allow the upper end of the duct <NUM> to begin to decouple from the rigid head <NUM> and this until the anchor has reached its most inclined position, linked to the shape and position of the obstacle (<FIG>).

In this phase the granular product <NUM> falls to the ground, unless its delivery is interrupted by an interception gate valve possibly provided in the connection <NUM> of the supply duct <NUM> or by another interception element foreseen in the path of the granular product before this comes out of the lower attachment <NUM>.

When the bolt <NUM> is then replaced or in any case when the correct working position of the leg <NUM> is restored after the obstacle has been overcome, the same forward rotation movement of the leg brings the duct <NUM> back into the correct working position, thanks also to the combined effect of the springs <NUM>, if provided, and of the cooperation between the further transverse bar <NUM>, fixed to the upper end of the duct itself, and the depression <NUM> obtained in the two bars <NUM> of the element guide <NUM>.

It is easy to recognize that the device according to the invention just described is quite advantageous, since in the event of an obstacle, in which one of the anchors <NUM> should eventually run into, the backward yielding of the anchor itself would not cause any damage to the supply duct <NUM> and to the delivery duct <NUM> of the granular products and the functionality of the equipment would be restored without any repairs.

Furthermore, it can be applied to any ploughing machine in a very simple and rapid form and is able to operate in a safe and reliable manner.

The variant embodiment illustrated in <FIG> differs from the embodiment described with reference to <FIG> in that it is capable of distributing and burying the granular products <NUM> at two different depth levels.

To this end, the rigid head <NUM>' of the attachment <NUM> is divided into two distinct ducts, one at the front and one at the rear, which extend into two similar ducts <NUM>, <NUM>', which correspond to the duct <NUM> of the previous embodiment.

The duct <NUM> continues between the two plates <NUM> to make the solid granular product <NUM> come out behind the anchor in a deeper position, while the duct <NUM>' ends at a higher height.

In this case, without prejudice to the operating principle, which is analogous to the previous one, it is possible to have the granular products <NUM> come out at two different depths into the ground, or else one overflow to the surface and one overflow in depth.

In order to have substantially the same flow of granular product that comes out of the ducts <NUM>, <NUM>', it may be advantageous for the internal wall of the cylindrical portion <NUM> of the lower attachment <NUM> of each supply duct <NUM> to present a plurality of protuberances which can be constituted by small bosses or by circumferential or spiral-shaped ribs or by protrusions of other shapes, which have the purpose of distributing the granular product <NUM> in a substantially uniform manner over the entire passage section in the attachment <NUM> and from here into the two ducts <NUM>, <NUM>'.

This characteristic, however, can also be advantageously provided in the previous embodiment, for production uniformity.

The invention also provides that the internal part of the cylindrical portion <NUM> can also have different conformations to obtain a differentiated distribution of the granular product flow according to the particular needs, for example <NUM>/<NUM> of granular product on the surface or at a shorter depth and <NUM>/<NUM> to greater depth.

Furthermore, the invention also provides for the simultaneous distribution of different solid granular products <NUM> contained in two different tanks and made to flow, through distinct ducts <NUM>, into the lower attachment <NUM> and from here into the rigid head <NUM> or <NUM>' to realise the distribution of equal or different dosages of the different products at the same or at different depths.

Furthermore, what has been described for one or two tanks is also valid in the case of three or more tanks, with the possibility of increasing the number of different solid granular products to be distributed simultaneously and / or the number of different distribution depths.

In a second embodiment, illustrated in <FIG>, while the fundamental principle underlying the present invention, its implementation methods, and in particular the methods of binding the duct for dispensing the granular products to the leg remain substantially similar of the anchor are slightly modified.

In particular, in this second embodiment, in which corresponding but modified elements are indicated with the same numerical references increased by <NUM>, while corresponding unmodified elements retain the previous numbering, the duct <NUM> is no longer articulated below the leg <NUM> of the <NUM>, and is no longer sliding with its upper part with respect to a guide integral with the frame of the subsoiler, but is articulated with its upper end to a support <NUM> integral with the frame of the machine and is sliding with its lower portion with respect to the leg <NUM> of the anchor <NUM>.

More particularly, a support <NUM> can be preferably fixed to the fork support <NUM>, to which the attachment <NUM> for the lower end of the feed duct of the granular product is constrained. Furthermore, the upper end of the duct <NUM> can be advantageously articulated to the same support <NUM> at a pin <NUM>, which is cut, as in the previous embodiment, according to a complementary pattern to the head <NUM> of the attachment itself, in so that the duct <NUM> can be moved between a working position, in which it extends the head <NUM>, and a position decoupled from this.

The lower part of the duct <NUM> is held in adherence to the rear edge of the leg <NUM> of the anchor <NUM>, when this is in operating condition (<FIG>), and this can preferably be obtained thanks to the engagement of a hook <NUM>, applied to the rear edge of the leg <NUM>, in a corresponding slotted opening made in the front wall of the duct <NUM> and not visible in the drawings.

This constraint mode, which allows the disengagement of the duct <NUM> from the guide <NUM> as soon as this begins to rotate backwards around the pin <NUM> following the impact against an obstacle, could however be replaced by different modes, such as for example one or more tension springs (not shown), interposed between the duct <NUM> and the leg <NUM>, or a torsion spring applied to the pin <NUM>.

While the constraint in adherence of the duct <NUM> to the leg <NUM> in working condition by means of the hook <NUM> requires the intervention of the operator to engage the hook <NUM> in the corresponding opening of the duct <NUM>, the constraint in adherence of the duct itself to the leg <NUM> can take place automatically, if one of the elastic return means described above is used.

Claim 1:
Device for the distribution and burying of solid granular products, to be applied to a subsoiler (<NUM>) or similar, comprising:
- a frame (<NUM>),
- a plurality of anchors (<NUM>,<NUM>) individually mounted on said frame (<NUM>) and configured to create corresponding grooves in the ground intended to receive said solid granular products (<NUM>),
- a plurality of substantially rigid ducts (<NUM>,<NUM>,<NUM>', <NUM>) placed behind the respective anchors (<NUM>,<NUM>),
- a plurality of supports (<NUM>), which are integral with said frame (<NUM>) and to which said anchors (<NUM>,<NUM>) are articulated in order to be moved between an active condition, with their lower end introduced into the ground, and an inactive condition overturned backwards, following impact against an obstacle in the ground,
- controlled yielding means, which keep each anchor (<NUM>,<NUM>) in an active condition in the absence of stresses exceeding a predetermined value, which should arise when said anchor (<NUM>,<NUM>) impacts against said obstacle,
- at least one tank (<NUM>) containing said granular product (<NUM>) to be distributed and buried,
- at least one supply duct (<NUM>) connecting said tank (<NUM>) with each of said substantially rigid ducts (<NUM>,<NUM>,<NUM>', <NUM>) when the corresponding anchor (<NUM>,<NUM>) is in an active condition,
wherein each of said substantially rigid duct (<NUM>,<NUM>,<NUM>', <NUM>) is articulated to said anchor (<NUM>, <NUM>), characterized in that
each of said substantially rigid duct (<NUM>, <NUM>, <NUM>', <NUM>) is associated with guide means, which following said controlled yielding make it pass from an active position, in which the upper end of said substantially rigid conduit (<NUM>,<NUM>,<NUM>', <NUM>) communicates with said supply conduit (<NUM>), to an inactive position, in which the upper end of said substantially rigid duct (<NUM>,<NUM>,<NUM>', <NUM>) is decoupled from said supply duct (<NUM>).