DESCRIPTION

The invention relates to a rapid attachment for sowing machines, with which a side of an articulated parallelogram type mechanism of a sowing element can be engaged with an element-carrying bar of a precision type agricultural sowing machine.

In the technical field of precision type agricultural sowing machines, which are generally used for single-grain sowing, it is known to mount a plurality of sowing elements on an element-carrying bar in order to constitute a multi-row agricultural sowing machine.

The attachment with which the sowing elements are secured to the element- carrying bar comprises a first portion which carries a clamping member, which can slide along the bar where applicable, and a second portion which constitutes a side of an articulated parallelogram type mechanism with which the sowing element is pulled by the bar with the capacity for following the profile of the sowing ground.

In order to remove the sowing element from the bar, it is necessary to open the jaws of the clamping member so as to be able to disengage it completely from the bar.

This operation involves a number of disadvantages, including the need to manoeuvre sowing elements which are relatively heavy in order to disengage the clamping members with the additional problem of the small parts necessary for the engagement possibly falling, such as screws, bolts, pins and the like.

It is clear that this operation, in addition to being laborious, involves the possibility of losing the above-mentioned small parts on the ground.

AU2009/100124 describes a rapid engagement system for unitary elements of a cultivator with an element-carrying bar. This involves a pivotable arm type system with a spring-mounted damper which keeps it pressed on the ground. The system can be disengaged and re-engaged in an easier manner using a tool-carrying bar but cannot be practically used in an agricultural sowing machine in which the sowing elements have to be connected to the element- carrying bar by means of a mechanism which allows the movement upwards and downwards of the element while keeping it parallel therewith, as typically occurs in an articulated parallelogram type system. Furthermore, the system described provides for a rotatable connection about a vertical axis so as to produce a possible horizontal swinging of the element which is carried, which is unsuitable for an agricultural sowing machine.

EP3228170 describes a device which forms a side of an articulated parallelogram for supporting a sowing element of a sowing machine. This side comprises two portions which are assembled together in an adjustable manner by means of screws and bolts in order to block the sowing element along a beam of the frame of the sowing machine in order to facilitate the positioning of the element along the beam. This device is subject to the disadvantages mentioned in the introduction.

Other devices are described in W02011/119093 and US9832924.

The object of the invention is to facilitate the disassembly and the re-assembly of the sowing elements on/from the element-carrying bar of the sowing machine, overcoming the disadvantages set out with reference to the cited prior art. This object is achieved by the invention by means of an attachment produced according to the appended claims.

The features and advantages of the invention will be better understood from the following detailed description of a preferred embodiment thereof which is illustrated by way of non-limiting example with reference to the following Figures. In the drawings:

• Figure 1 is a perspective view of a sowing element with an attachment to an element-carrying bar according to the invention;

• Figures 2 and 3 are a side view and a perspective view, respectively, of the attachment of the sowing element of Figure 1;

• Figures 4 and 5 are views corresponding to those of Figures 2 and 3 of the same attachment in the engaging/disengaging step.

In the Figures, there is generally designated 1 a sowing element of a precision type agricultural sowing machine which is generally designated 100. Preferably, a plurality of sowing elements 1 are engaged by means of a respective (rapid) attachment 3 in a sliding or fixed manner on an element-carrying bar 4 of the sowing machine 100.

Preferably, the above-mentioned engagement can slide for the provision of runners 28 and pulling members 29 involving a sowing element 1 which is intended for a sowing machine 100, the bar 4 of which is foldable for transport on roads, but it is evident to a person skilled in the art that the same concept of engagement can be adapted to sowing elements which are mounted in a fixed manner on the element-carrying bar.

The sowing element 1 comprises a frame 6, to which there are articulated with a respective end thereof two pairs of arms, upper arms 7 and lower arms 8, respectively, of an articulated parallelogram type mechanism which is generally designated 9, the opposite sides designated 10 and 11, respectively, of which are preferably constituted by a portion of the frame 6 and by a second portion 12 of the attachment 3.

According to an embodiment of the invention, the first portion 2 of the attachment 3 is the one with which the attachment is engaged with the element-carrying bar 4 and remains mounted in a stable manner on this bar even when the sowing elements 1 are removed therefrom.

The second portion 12 of the attachment 3 is removably connected to the first portion 2 by means of a rapid engagement mechanism.

This first portion 2 comprises two opposing channels 13 which face each other and which are connected by uprights 16 so as to generally form a seat for receiving the bar 4, with a general formation which is preferably similar to an inverted C.

At the longitudinally opposite ends of the uprights 16, there are formed a pair of hooks 17 and a fixing device 18 with one or two rods 19, respectively, which are preferably screw type rods and which can be oscillated on the respective upright 16 and clamping member 20 (in particular, a clamping nut 20) which is partially screwed onto the shank of the rod 19. In this manner, the movable portions of the fixing device 18 are secured in a loss prevented manner on the first portion 2 of the attachment 3.

The pair of hooks 17 defines a cradle 27 which is open upwards and which is intended to receive in a removable manner a pin 30 which is fixed to the second portion 12 of the attachment 3.

More generally, one of the portions 2, 12 of the attachment 3 has a cradle 27 while the other portion has the pin 30 which is capable of being received in an oscillating manner in the cradle 27. Preferably, the rapid engagement mechanism comprises the cradle 27 and the pin 30 mentioned above. The rapid engagement mechanism may further comprise the fixing device 18.

The pin 30 is fixed between two plates 21 of the second portion 12, each being provided with a wing 22 which, with the attachment 3 assembled, is arranged behind the respective upright of the first portion 2.

Preferably, the two plates 21 are provided with hinging holes 23 for the respective ends of the arms 7, 8 of the parallelogram type mechanism 9, therefore constituting a side of the above-mentioned mechanism 9.

The two wings 22 are provided, at the opposite side to the pin 30, with a respective slot 24 and, in an intermediate portion between the pin 30 and slot 24, with a hole 25, in which there is received the head 26 of a centring pin which is provided in a corresponding position on the first portion of the attachment 3.

The slots 24 supplement the fixing device 18 by receiving the rod 19 of the first portion in order to prevent the relative oscillation between the portions 2, 12 once they are coupled about the X axis of the cradle 17.

The holes 25 and the heads 26 of the pins constitute in turn engagement means and engagement counter-means in order to prevent relative sliding between the portions 2, 12 once engaged with each other.

In order to rapidly engage a sowing element 1 with the element-carrying bar 4, it is simply necessary to lift it, arrange it with the pin 30 in the cradle 27 which is defined by the hooks 17 and allow it to be arranged by means of gravitational force with the wings 22 placed against the uprights 16. Then, there is carried out the engagement of the screw type rod 19 in the respective slot 24 and the tightening of the nut 20 so as to block the assembly. The disengagement is brought about just as rapidly by following the same operations in reverse.

If necessary, it is possible to connect the optional rods which are provided for sliding the sowing elements 1 along the sowing bar 4.

The main advantage of the invention is making the assembly and disassembly of the sowing elements with respect to the element carrying bar of the sowing machine extremely easy and rapid. In addition to being fast, this operation is particularly easy as a result of the simplicity of the rapid attachments used. Furthermore, the connection is secure both as a result of the fact that it benefits from gravitational force in order to keep the attachment closed and as a result of the fact that the portions subjected to possible loss are carried at the attachment side which remains fixed to the bar and therefore cannot be lost.