PLOW

Abstract

A plough (1) with a three-point linkage head (4) for connecting the plough (1) to a three-point elevator (5) of a tractor (T), two lower points (9) of the head (4) being arranged on a steerable support (10) on the head (4) with respect to a frame (6) thereof about a steering axis (X1), a third upper point (9A) of the head (4) being carried by a pivotable support (11) on the frame (6) about a pivot axis (X2), the pivotable support (11) being able to be removably secured to the frame (6) about the pivot axis (X2) in order to configure the plough (1) in a carried condition, and able to be released from the frame (6) in a pivotable manner about the pivot axis (X2) in order to configure the plough (1) in a half-carried condition, the pivotable support (11) further being able to be tilted about a tilting axis (X3) which is substantially parallel with the steering axis (X1) in the position released from the frame (6). The pivotable support (11), when it is secured to the frame (6), can be pivoted in a limited manner with respect to the frame (6) in a manner opposed by damping means (22) which are provided between the frame (6) and the pivotable support (11).

Description

[0001] PLOUGH

[0002] DESCRIPTION

[0003] The present invention relates to a plough, preferably of the reversible type provided with a steerable head according to the preamble of the main claim.

[0004] A plough including these features is known from IT 102013902147277.

[0005] These ploughs typically have a carrier structure, on which there are mounted pairs of opposite ploughing members and which can be orientated between two work positions which are opposite each other at 180° and an intermediate transport position. In the work positions, the plough is integrally carried on the three-point elevator of the tractor which pulls it while, in the transport position, the plough is half-carried while remaining pulled by the two lower points of the three-point linkage, while the structure is also supported via a transport wheel. These ploughs generally have a high number of pairs of ploughing members and a substantial resultant length of the carrier structure as well as a very high total mass. For these reasons, the ploughs of this type are normally half-carried in the transport phase and have a steerable head. The steering of the head is brought about via rotation of the support of the head which carries the two lower linkage points with respect to the frame of the head. When the ploughs are in a transport position, it is necessary for the third linkage point to the tractor to be disengaged. This serves to prevent, during steering of the head, the arm which connects the third linkage point of the tractor from damaging the structures of the plough and / or the tractor as a result of the effect of the misalignment thereof with respect to the work position. Conversely, in a work position, it is necessary for the third point to be securely connected to the plough head. Often, the operators forget to disconnect the third point when the plough is half-carried in a transport position and therefore damage is caused. In order to overcome this, there have been adopted arrangements which allow the head of the plough to be steered without having to release the third point. These arrangements are based mainly on mounting the third linkage point at one end of a support which is articulated to the frame of the head so that it can be rigidly secured to the frame in the work phase and can pivot freely during the transport phase.

[0006] However, the above-mentioned ploughs are subject to another problem which mainly occurs when, at the end of the furrow, the tractor reverses the direction of travel in order to continue ploughing in the opposite direction. During the travel reversal step, the plough is raised and integrally carried on the three- point elevator of the tractor, bearing down on it without any auxiliary member. At the end of the furrow (so-called headland), as a result of the repeated reversals of travel, often such ground conditions are encountered as to apply to the plough and the three-point elevating system substantial and unexpected stresses which, taking into account the suspended mass, can damage both the plough and the tractor.

[0007] Some ploughs, see, for example, EP4147546A1, are provided to this end with shock-absorbing systems which are intended to absorb these violent excess stresses.

[0008] Until now, however, the systems which allow the plough to be pulled in a transport position without disengaging the third point do not allow damping of the stresses on a plough which is raised, and vice versa, the systems which allow damping of the above-mentioned stresses do not allow the plough to be pulled without disengaging the third point.

[0009] The problem addressed by the present invention is to provide a plough which is structurally and functionally configured so as to allow at least some of the disadvantages set out with reference to the cited prior art to be overcome.

[0010] In this context, an object of the invention is to develop a plough which allows both easier disengagement of the third point without having to disengage it from the head of the plough and an effective damping effect with the plough being carried.

[0011] Another object of the invention is to provide a plough which does not require substantial structural modifications with respect to the models currently in production.

[0012] Another object is to develop a plough which is capable of what is set out above and which at the same time has a simple and robust structure.

[0013] In a first aspect thereof, the present invention is directed towards a plough with a three-point linkage head for connecting the plough to a three-point elevator of a tractor, two lower points of the head are arranged on a steerable support with respect to a frame of the head about a steering axis, a third upper point of the head is carried by a pivotable support on the frame about a pivot axis.

[0014] The pivotable support is preferably able to be removably secured to the frame about the pivot axis in order to configure the plough in a carried condition, and able to be released from the frame in a pivotable manner about the pivot axis in order to configure the plough in a half-carried condition.

[0015] Preferably, the pivotable support can be tilted about a tilting axis which is substantially parallel with the steering axis in the position released from the frame.

[0016] According to a preferred feature of the invention, the pivotable support, when it is secured to the frame, can be pivoted in a limited manner with respect to the frame in a manner opposed by damping means which are provided between the frame and the support.

[0017] In this manner, when the plough is raised in a carried condition, the damping means can attenuate the pulse type stresses which are potentially capable of damaging both the plough and the tractor.

[0018] Preferably, the pivotable support is secured to the frame pivotably in a limited manner about a securing axis and the pivot axis can be pivoted in a limited manner with respect to the frame along a path which is concentric with respect to the securing axis.

[0019] In this manner, the securing axis of the pivoting support further acts as a hinge for allowing the damped pivoting of the plough.

[0020] According to one possible exemplary embodiment, the pivotable support is articulated on the frame through a first hinge element, preferably a pin, which defines the pivot axis. Preferably, the first hinge element is secured in at least one slot which is elongate in the direction of the concentric path. The slot, as a result of the limited travel of the pivoting action, can be rectilinear or arcuate but in all cases develops with the greater axis tangent to or concentric with the pivoting path.

[0021] In a preferred embodiment of the invention, the tilting axis is defined by a second hinge element which is fixedly joined to the first hinge element and which is movable, as a result of the pivoting of the pivotable support, between a position received in the frame, in which the tilting axis is substantially angled in a non-parallel manner with the steering axis, and a tilting position, in which the tilting axis is substantially parallel with the steering axis. This solution is particularly compact and ensures optimum protection of the components. According to a preferred embodiment, the securing axis is defined on an axis of holes of the frame in which a pin is removably engaged. The holes are preferably formed in respective opposite shoulders of the frame. This solution is a very simple and immediate method for obtaining the removable securing during pivoting of the pivotable support.

[0022] The holes are preferably formed in the respective shoulders at the same distance from a base of the frame so that the axes of the holes are aligned with each other. Desirably, the holes substantially have the same diameter.

[0023] Preferably, the pivotable support is hinged between the shoulders of the frame. Preferably, the pivotable support, when in a condition secured to the frame, is at least partially received between the shoulders.

[0024] In one embodiment of the invention, the second hinge element is substantially external with respect to the shoulders when the support is in the tilting position. This allows a tilting angle which is particularly great and advantageous, increasing the possibility of steering the plough around tight bends.

[0025] The features and advantages of the invention will be better appreciated from the following detailed description of a preferred though non-exclusive embodiment thereof which is illustrated by way of non-limiting example with reference to the appended drawings, in which:

[0026] - Figure 1 is a partial perspective view of a plough according to the invention in a transport position and in a half-carried condition;

[0027] - Figure 2 is a partial perspective view of the plough of Figure 1 in a work position and in a carried condition;

[0028] - Figures 3 and 4 are side views of the plough of the preceding Figures in the respective transport and work positions; - Figure 5 is the partial perspective view of the plough of Figure 2 in which some elements are transparent in order to show a number of details which otherwise are not visible;

[0029] - Figure 6 is a partial perspective view of the plough at the opposite side with respect to Figure 2.

[0030] In the Figures, there is generally designated 1 a plough of the reversible type which is illustrated in Figure 3 in a transport position and in a half-carried (or pulled) condition, for example, in order to be pulled on roads in the transport position. In the example of Figure 4, the plough is illustrated in a carried condition, for example, by a tractor T, and in a work position or operating position.

[0031] The invention is preferably, though not exclusively, suitable for being fitted to ploughs of this type which generally comprise a carrier structure 2, on which there are mounted opposite pairs of ploughing members 3. The structure 2 carries at one end a head 4 with which the plough 1 can be connected to an elevator 5 of the tractor T, generally a hydraulic elevator 5 which is provided with a three-point linkage, meaning two lower arms 7 and an upper tie rod 8. The structure 2 carries, at an opposite end, a wheel R. which serves both to regulate the depth of ploughing and to transport the plough 1 in the half-carried condition, meaning when the head 4 is supported and pulled by only the lower arms 7 of the elevator 5 of the tractor T and the tie rod 8 which is connected to the third point could (or at times should) be released from the plough 1.

[0032] An object of the invention is to develop a plough 1 which allows the tie rod 8 to be kept connected in the transport position without damaging either the plough 1 or the tractor T and which improves the "portability" thereof in the purely carried condition of Figure 4.

[0033] The three-point linkage head 4 comprises a carrier frame 6 which carries a steerable support 10 about a steering axis XI and which carries two lower points 9 of the three-point linkage, preferably of the quick-attachment type which is known per se, which are arranged at opposite ends of the steerable support 10. A third upper point 9A of the head 4 is carried by a pivotable support 11 on the frame 6 about a pivot axis X2. The pivotable support 11 can be removably secured to the frame 6 so as to prevent the pivoting thereof about the pivot axis X2 by means of a pin 13 which can be removably inserted in a pair of holes 14 of the frame 6 and in a corresponding hole 15 of the pivotable support 11. The axis of the holes 14 defines a securing axis X4, as will be better explained below. The holes 14 are preferably formed in respective shoulders 17 of the frame 6 which are upright with an arrangement parallel and spaced apart from a base 18 of the frame 6 so that there is defined between the shoulders 17 a housing 16, in which there is preferably received, in a main manner, the pivotable support 11 when it is secured to the frame 6. The secured mode with respect to the frame 6 of the pivotable support 11 serves to raise the plough 1 in the carried condition, which is still necessary when the plough 1 is in the work position of Figure 4. Similarly, by removing the pin 13 so as to allow the pivotable support 11 to pivot freely with respect to the frame 6 of the plough, the plough 1 is supported in a steerable manner about the steering axis XI in the transport position of Figure 3.

[0034] When the pivoting of the pivotable support 11 with respect to the frame 6 is released as a result of the effect of the removal of the pin 13 and the third point 9A is provided to be secured to the tie rod 8, the pivotable support 11 itself becomes tiltable about a tilting axis X3 which is substantially parallel with the steering axis XI. The term "substantially" serves to indicate that a rigorous condition of parallelism does not necessarily have to exist, the support 11 being pivotable about the axis X2, rather an approximately parallel condition as will be explained below.

[0035] The pivot axis X2 and tilting axis X3 can preferably be defined by respective pins 19, 20 which act as hinge elements for the pivot axis X2 and tilting axis X3, respectively. In a preferred structural embodiment of the invention, the first pin 19 has axially opposite ends which are received in respective slots 21, which are orientated in such a manner that, when the pivotable support 11 is secured to the frame 6 by means of the pin 13, it is further pivotable in a limited manner about the securing axis X4, allowing a limited movement of the pivot axis X3 with respect to the frame 6 along a path which is concentric with respect to the securing axis X4.

[0036] In one embodiment of the invention, the pins 19, 20 are fixedly joined to each other and the second pin 20 extends in a central position and perpendicularly with respect to the first pin 19. In a preferred embodiment of the present invention, when the pivotable support 11 is secured to the frame 6 in the carried condition of the plough 1, the pivotable support 11 itself can be pivoted in a limited manner with respect to the frame 6 about the securing axis X4 in a manner opposed by damping means 22 which are provided between the frame 6 and pivotable support 11.

[0037] As can be seen in the embodiments of Figures 5 and 6, the damping means 22 preferably comprise a hydraulic actuator 23, in which a cylinder 25 is rotatably secured by means of brackets 26 to the ends of the first pin 19. The actuator 23 can have a rod 28 which is secured to the frame 6 by means of a pin 29 and can be hydraulically connected to a hydraulic tank 30 so as to damp the stresses which produce a movement of the first pin 19 in the slots 21.

[0038] In a preferred aspect of the invention, the second pin 20 forms with the pivotable support 11 a second hinge element which is fixedly joined to the first hinge element and which is movable as a result of the pivoting of the pivotable support 11 between a position mainly received in the frame 6, in which the tilting axis X3 is substantially angled in a non-parallel manner with the steering axis XI, and a tilting position, in which the tilting axis X3 is substantially parallel with the steering axis XI. In other words, when the pivoting support 11 is secured to the frame 6, it is substantially received between the shoulders 17, thereby making impossible any pivoting thereof about the tilting axis X3. Conversely, when the pivoting support 11 is pivoted into the position of Figure 1, the second pin 20 and the relevant hinge element are completely removed from the shoulders 17, therefore acquiring a substantial capacity for tilting the pivotable support 11. This allows a high capacity for also steering the plough 1 around tight bends without damaging the head 4. It will be observed that, with a positioning of the tilting axis X3 approximately parallel with the steering axis XI, this function is further facilitated.

[0039] In the secured position of the pivoting support 11 by means of the pin 13 with respect to the frame 6, the plough 1 is transported by the tractor T as a carried equipment item. That is to say that the plough 1 can integrally be raised by means of the three points of the linkage 9, 9A without any need to support it on the ground by means of the wheel R. This condition occurs only when the plough 1 is raised by the hydraulic elevator 5 of the tractor T, for example, during reversals of travel on the headland. In this case, the stresses between the tie rod 8 and the frame 6 by means of the pivoting support 11 are damped by the damping means 22 as a result of the capacity of the first pin 19 for sliding in the slots 21 with a pivoting action centred on the axis of the pin 13 (example of Figure 4).

[0040] Conversely, by moving into the transport position (example of Figure 3), the pin 13 is removed bringing about the pivoting of the pivoting support 11 about the pivot axis X2 and obtaining the substantial vertical positioning of the second pin 20 and relevant hinge element and therefore releasing the possibility of tilting of the pivoting support 11 about the tilting axis X3. The tilting is not obstructed by the shoulders 17 of the frame as a result of the complete extraction of the pin 20 from the position received between the shoulders 17. At this point, it is not necessary to release the third point 9A from the tie rod 8 and the plough 1 is supported on the lower arms 7 of the tractor T by means of the linkages 9 and on the wheel R. which is supported on the ground. The plough 1 can be steered by means of rotation of the steering support 10 about the axis XI.

[0041] The invention thereby solves the problem proposed, affording a number of advantages, including:

[0042] - the possibility of having a single plough system 1 which is capable of damping in a carried condition and of releasing the third point 9A without requiring the disengagement thereof in a pulled or half-carried condition;

[0043] - the possibility of preserving the service-life of the plough 1 and the tractor T in all the phases in which they are exposed to great stresses;

[0044] - the advantage of a compact system with minimal weight increase and with few components and with members which can largely be used even in ploughs of different types.

Claims

1. A plow (1) with a three-point hitch (4) for connecting the plow (1) to a three-point lift (5) of a tractor (T), wherein two lower points (9) of the hitch (4) are located on a controlled support (10) on the hitch (4) relative to its frame (6) around a control axis (X1), and a third upper point (9A) of the hitch (4) is mounted on a pivot support (11) on the frame (6) around a rotation axis (X2), wherein the pivot support (11) is configured to be removable secured to the frame (6) around a rotation axis (X2) to set the plow (1) in a portable state and with the possibility of disconnecting from the frame (6) by rotating around a rotation axis (X2) to set the plow (1) in a semi-attached state, wherein the pivot support (11) is also configured to tilt around an axis (X3) tilt, which in the position of disconnection from the frame (6), is essentially parallel to the control axis (X1), characterized in that the rotary support (11), when secured to the frame (6), is designed with the possibility of limited rotation relative to the frame (6),which is prevented by damping means (22) located between the frame (6) and the pivot support (11)., 2. A plow (1) according to claim 1, in which the rotary support (11) is secured to the frame (6) with the possibility of limited rotation around the axis (X4) of fastening, and the axis (X2) of rotation is designed with the possibility of limited rotation relative to the frame (6) along a trajectory concentric with respect to the axis (X4) of fastening.

3. A plow (1) according to claim 2, in which the pivot support (11) is pivotally connected to the frame (6) by means of a first pivot element forming an axis (X2) of rotation, wherein the first pivot element is secured in at least one groove (21) which is elongated in the direction of the concentric trajectory.

4. The plow (1) according to claim 3, in which the tilt axis (X3) is formed by a second hinge element, which is rigidly connected to the first hinge element and is designed with the possibility of movement as a result of rotation of the pivot support (11) between a position obtained in the frame (6), in which the tilt axis (X3) is tilted at an angle that is substantially not parallel to the control axis (X1), and a tilt position in which the tilt axis (X3) is substantially parallel to the control axis (X1).

5. A plow (1) according to any one of paragraphs 2-4, in which the axis (X4) of fastening is formed on the axis of the openings (14) of the frame (6), into which the kingpin (13) is removably inserted, and the openings (14) are formed in the corresponding opposite arms (17) of the frame (6).

6. The plow (1) according to claim 5, in which the pivot support (11) is installed between the arms (17) of the frame (6), and the pivot support (11), when secured to the frame (6), is at least partially installed between the arms (17).

7. A plough (1) according to claim 5 or 6, in which the second hinge element is substantially external to the arms (17) when the pivot support (11) is in an inclined position.