Grass-cutting equipment

Abstract

Grass-cutting equipment (1) applicable to a self-propelled vehicle (2), comprising: a main frame (5); a connection system (60) to the self- propelled vehicle (2) for moving the equipment (1) in an advance direction (A); at least one cutting element (20); at least one cutting group (17, 18) which is configured to support the cutting element (20) in a work position, the at least one cutting group (17, 18) being mounted on the main frame (5) in a manner able to be moved in translation in a translation direction (T) which is transverse to the advance direction (A); and a movement device (61) of the at least one cutting group (17, 18) along the translation direction (T). The movement device (61) comprises a linear actuator (39) and a travel multiplier (35) of the linear actuator (39) which is interposed between the linear actuator (39) and the corresponding cutting group (17, 18).

Description

[0001] Grass-cutting equipment

[0002] DESCRIPTION

[0003] The present invention relates to a grass-cutting equipment applicable to a self-propelled vehicle.

[0004] It is known that the proliferation of fungal, bacterial and parasitic species in general is also directly correlated to the presence of weeds. Controlling the above-mentioned pests requires controlled conditions to be maintained in inter-row lanes. This control is exercised either with herbicides and chemical pesticides (some of which are highly toxic and in any case harmful to the environment) or, and preferably, with frequent grass cutting in interrow lanes.

[0005] In this second type of control action, which is purely mechanical, it is important to minimise the working path of the machinery used. This makes it necessary in each lane to pass only once, working the centre of the lane and at the same time both rows flanking its two sides. Recently, selfdriving vehicles (so-called rovers) have appeared on the market, capable of carrying out agricultural work without any operator physically on board. These vehicles are particularly popular for carrying out highly repetitive work such as inter-row work in vineyards, orchards and similar crops arranged in rows. Among the great advantages of such equipment is the fact that it can work continuously and even at night. However, it is important that the equipment mounted on these rovers allows a high degree of safety both for people and animals and for the treated crops. Imperatively, immediate stop means and / or adjustment means of the functionality of the equipment and the rover on which it is installed must be provided.

[0006] A grass-cutter made according to the prior art is described for example in

[0007] IT202000009904A1.

[0008] The technical problem underlying the present invention is to provide a grass-cutting equipment structurally and functionally designed to optimise grass cutting in the inter-row lanes of agricultural and forestry crops. In the context of this problem, it is an important aim of the invention to devise such equipment capable of a complete cut in a single passage along the inter-row lanes. Another important aim of the invention is to provide equipment suitable for equipping self-driving vehicles. It is also an aim of the present invention to provide grass-cutting equipment that allows for an adequate movement capacity of the cutting means in a compact solution.

[0009] This problem is solved and these aims are achieved, at least in part, by the invention in a first aspect by a grass-cutting equipment applicable to a self- propelled vehicle.

[0010] Preferably the grass-cutting equipment comprises a main frame and a connection system to the self-propelled vehicle for moving the equipment along an advance direction.

[0011] Preferably the grass-cutting equipment comprises at least one cutting element and at least one cutting group configured to support the cutting element in a working position. Preferably the at least one cutting group is mounted on the main frame in a traversable manner along a translation direction transverse to the advance direction.

[0012] Preferably the grass-cutting equipment comprises a device for moving the at least one cutting group in the translation direction.

[0013] It is preferred that the movement device includes a linear actuator.

[0014] Further preferred is that the movement device comprises a travel multiplier of the linear actuator interposed between the linear actuator and the corresponding cutting group.

[0015] Advantageously, the travel multiplier allows a greater travel in relation to the overall size of the movement system and at the same time can also increase the movement speed of the cutting group. This results in a simple and compact movement mechanism that optimises grass cutting in interrow lanes.

[0016] In addition, due to the presence of the travel multiplier, the linear actuator can have a smaller longitudinal extension and therefore less exposure to dust rising from the ground during grass-cutting operations.

[0017] Due to its compactness, the grass-cutting equipment is particularly suitable for self-driving vehicles. In a second aspect, it should be noted that the present invention relates to a self-propelled, self-driving vehicle to which the grass-cutting equipment is applied. More specifically, the grass-cutting equipment can be attached to a lifting device of the self- propelled, self-driving vehicle.

[0018] The present invention in at least one of the above-mentioned aspects may also have one or more of the following preferred features in addition to those previously mentioned.

[0019] Preferably, the travel multiplier comprises a lever mechanism connected to the corresponding at least one cutting group, to a fulcrum on the main frame and to the linear actuator so as to move the at least one cutting group along the translation direction. These features allow the travel multiplier to be realised in a simple manner, thus ensuring high reliability. Preferably the lever forms a lever of the second or third type with the linear actuator. Such types prove particularly advantageous in allowing a compact mechanism.

[0020] It is preferable for the lever to be hinged to the main frame in the region of a first end thereof and to be secured to the at least one cutting group in the region of a second end thereof. Further preferred is that the linear actuator is connected to the lever in the region of an intermediate position of the lever. This makes it possible to provide the grass-cutting equipment and the related movement mechanism through a simple and rational structure.

[0021] Preferably, the lever is secured to the at least one cutting through a slot and pin system, whereby the pin is slidingly engaged in the slot. In embodiments the lever has the slot and the at least one cutting group has the pin or vice versa. These features make it possible to further increase the distance that the actuator travel allows the cutting group to achieve.

[0022] Preferably, each cutting group is mounted on at least one guide through a respective slider. More specifically, a pair of guides and relevant sliders are provided for each cutting group. In this way, the translation arrangement of the constraint between the lever and the cutting group is made simple and particularly robust.

[0023] Preferably there are at least two cutting groups, at least one of which is translatable. Even more preferably, the cutting groups are driven by respective linear actuators independently. This not only multiplies the travel of the cutting group with respect to the available travel through the actuator, but also provides an independent drive of the two cutting groups in both lateral extension and retraction towards the centre of the equipment.

[0024] Preferably each cutting group comprises a lateral extent sensor for protection in the event of collision during the opening of the equipment.

[0025] Preferably each cutting group comprises at least one motor driving a respective rotor carrying a respective cutter. Even more preferably, each cutting group comprises a plurality of rotors connected to the at least one motor and carrying respective cutters.

[0026] Preferably the at least one motor is connected in cascade to the plurality of rotors. Even more preferably, the last rotor of the cascade is provided with a sensor which controls the rotation speed thereof. In this way, a single sensor can detect faults (e.g. belt breakage or grass jamming) on the entire rotor train connected in cascade.

[0027] Preferably for each of the rotors there is provided a driven shaft and a scraper which is mounted tangentially relative to the shaft. Advantageously, the scraper prevents excessively long grass from being picked up by the rotor and wound onto the corresponding shaft.

[0028] Preferably the grass-cutting equipment comprises one or more wheels for support on the ground, which are connected to the main frame. In this way, the cutting height can be precisely defined through the support wheels.

[0029] Preferably the grass-cutting equipment also comprises a detection system configured to detect the support of the wheels on the ground. This feature makes it possible to close a control circuit when the wheels are resting on the ground in the appropriate working position and open the circuit causing the cutting groups to stop immediately as soon as the wheels are lifted off the ground.

[0030] Preferably, the wheels are connected to the main frame in an adjustable manner by way of an adjustment device which is configured to adjust the height of the wheels with respect to the location plane of the cutting element.

[0031] Preferably, the connection system to the self-propelled vehicle is connected to the main frame on the opposite side with respect to the wheels. This arrangement facilitates the towing of the equipment.

[0032] Preferably, the connection system comprises a three-point hitch, preferably of the carried or semi-carried type. Advantageously, the carried type hitch allows the equipment to transmit its full weight to the ground through the vehicle to which the equipment is applied. Conversely, the semi-carried hitch allows its weight to be partially transmitted to the ground through one or more of the wheels fitted to the equipment itself.

[0033] Further preferred aspects are also defined in the appended claims as well as in the following description.

[0034] The characteristics and the advantages of the invention will become clearer from the following detailed description of a preferred but not exclusive embodiment illustrated, by way of non-limiting example, with reference to the accompanying drawings wherein:

[0035] Fig. 1 is a side view of a self-propelled vehicle to which the grasscutting equipment according to an embodiment of the present invention is applied;

[0036] - Fig. 2 is a side view of the grass-cutting equipment according to an embodiment of the present invention;

[0037] - Figs. 3 and 4 are perspective views from above of the grass-cutting equipment in Figure 2 in two different working positions;

[0038] - Fig. 5 is a perspective view from below of the grass-cutting equipment in the working position of Figure 3 in which some parts have been removed to show others not normally visible;

[0039] - Fig. 6 is a perspective view from below of the grass-cutting equipment in the working position of Figure 4;

[0040] - Fig. 7 is a cross-sectional side view of a detail of the grass-cutting equipment in Figure 2;

[0041] - Fig. 8 is a perspective view from below of a detail of the grasscutting equipment in Figure 2.

[0042] In the figures, 1 denotes a grass-cutting equipment applicable to a self- propelled vehicle 2 such as, preferably, a self-driving vehicle preferably equipped with a lifting device 3 comprising lifting arms 31 for transporting and towing agricultural equipment.

[0043] With particular reference to the examples of Figures 1 and 2, the equipment 1 comprises a main frame 5 equipped with a three-point hitch

[0044] 4 with which the equipment 1 is connected to the lifting arms 31 and to a third-point strut 6 in a conventional manner. The hitch 4 is a connection system 60 to the vehicle 2.

[0045] With particular reference to the examples of Figures 3 to 6, the main frame

[0046] 5 preferably comprises a pair of longitudinal members 8 and a secondary frame 9, e.g. with an essentially rectangular plan, to the side of which, opposite the hitch 4, a rear subframe 10 carrying a pair of wheels 11, preferably pivoting, is attached. The wheels 11 are used to adjust the working height H of the equipment 1 in the manner explained below.

[0047] Preferably, to the secondary frame 9 there are fixed a first and a second pair of guides 12, 13 preferably linear, for example made from cylindrical rods 15 on which sliders 16, for example and preferably of the ball recirculation type, are slidably mounted. For the sake of clarity of the above-mentioned figures, the cylindrical rods 15 and sliders 16 are only shown at a guide of the first pair of guides 12.

[0048] Preferably through such sliders 16, on the guides 12, 13 a first and a second cutting group 17, 18 are mounted respectively, on each of which motors 19 possibly electric or, more preferably, hydraulic, are in turn mounted, which serve to rotatably drive cutting elements 20 such as bar cutters 20a or the like rotating about a vertical axis. It is understood that the same motor 19 may drive one or more of these cutters 20a.

[0049] In the example shown, a single motor 19 drives respective rotors 21 in cascade, each carrying a respective cutter 20a. Again, the reference numbers of the cutters 20a and rotors 21 are shown in the figures only at one of them.

[0050] The cascade connection means that the motor 19 of one of the cutting groups 17, 18 drives not only the respective rotor 21, but also the adjacent rotor 21 through a transmission, e.g. belt and pulley 22, 23. And so on: the second rotor 21 drives the third, and the third drives the fourth through respective transmissions 22, 23. The last rotor 21 of the cascade, in addition to being driven by the previous one, is also equipped with a speed sensor 25 that controls its rotation speed. In this way, if any of the previous rotors 21 in the cascade connection is slowed down, e.g. as a result of excessive power consumption, the slowdown is transmitted to all the rotors 21 in the cascade and is detected by the speed sensor 25.

[0051] With particular reference to the example in Figure 8, a scraper 26 is applied at one shaft 27 of each rotor. The scraper 26 serves to prevent excessively long grass from being collected by one or more rotors 21 and wound onto the corresponding shaft 27. This is one of the most frequent causes of excessive power consumption that can cause the rotors to slow down 21. The effect is prevented by the scraper 26, as it prevents this winding grass cutting the fibres in the bud. Preferably, the scraper 26 is positioned close to the shaft 27 without touching it.

[0052] Still with reference to the examples of Figures 3 to 6, it is preferred that each cutting group 17, 18 carries laterally a lateral extension sensor 28, e.g. comprising a strap 29 pivoted in an oscillating manner on the corresponding cutting group 17, 18 and acting on a push-button switch 30 when the strap comes into contact with any obstacle, e.g. a vine stump, pole or the like. This solution prevents the grass-cutting equipment 1 from getting stuck between two stumps. Alternatively, it is provided another type of lateral extension sensor 28, e.g. a multi-contact elastic element type sensor, typically comprising an elastomeric band, the crushing of which, even localised, leads to the closure of a signalling circuit. In all cases, it is preferred that the lateral extension sensor 28 pilots, as better explained below, the lateral movement of the respective cutting groups 17, 18 to vary the operating width of the equipment 1 depending, for example, on the inter-row dimensions of the lane being travelled between two adjacent rows of crops.

[0053] The sliding of the cutting groups 17, 18 is preferably carried out by two independent (preferably linear) actuators 39 so that each group is independently moved away from or towards the centre of the equipment 1. In order to allow an extension reduction of the travel of the actuator 39 with respect to the effective travel of the cutting group 17, 18, a travel multiplier 35 is used, preferably of the lever type 36; the latter is pivoted roughly at the centre of the equipment 1 on the main frame 5 through a fulcrum 37 and is configured to form a lever 36 preferably of the second or third kind, for example by connecting a movable rod 38 of the actuator 39 at an intermediate position between the fulcrum 37 and a force application point on the corresponding cutting group 17, 18. The force application point is, for example, a pin 50, defined on each of the cutting groups 17, 18, engaged in a slot 40 defined instead at the end of the lever opposite the fulcrum 37.

[0054] This not only multiplies the travel of the cutting group 17, 18 with respect to the available travel through the actuator 39, but also provides an independent drive of the two cutting groups 17, 18 in both lateral extension and retraction towards the centre of the machine.

[0055] The wheels 11 are connected to the main frame 5 in an adjustable manner through an adjustment device 62, configured to adjust the height H of the wheels 11 with respect to the location plane of the cutting groups 17, 18. More specifically, the adjustment of the grass cutting height H is carried out as follows. Both wheels 11 are pivoted both about their own vertical axis 41, to allow free orientation thereof, and about a horizontal axis 42 spaced apart from the vertical axis 41 by an arm 51 which is pivoted about the axis 42 in a bidirectionally angularly limited manner by the presence of two abutment pins 44. The terms "vertical" and "horizontal" refer to the configuration in which the grass-cutting equipment 1 is used and, more specifically, to directions that are essentially orthogonal and parallel to the ground.

[0056] Adjustment of the cutting height H is carried out by vertically moving a wheel support 53 with respect to the main frame 5 and constraining it by inserting a pin (not shown) in one of the holes of a pitched perforation 46. A safety sensor 47 such as a push-button switch, proximity sensor or the like is mounted through a plate 48 on the main frame 5 so that a control circuit is closed when the wheels are resting on the ground in the appropriate working position but the circuit is open causing the cutting groups to stop immediately as soon as the wheels are lifted off the ground. In embodiments, the equipment 1 comprises at least one manually operable emergency stop button 70 to immediately stop the cutting groups in the event of an emergency. Preferably there is an emergency stop button 70 positioned near each wheel 11.

[0057] During operation, the equipment 1 is connected to a self-propelled vehicle 2 through the hitch 4 and is set in motion along a predetermined advance direction A.

[0058] The simultaneous or independent drive of the actuators 39 allows the cutting groups 17 and / or 18 to be moved in a transverse direction T until the desired positioning is achieved, depending on the width of, for example, an inter-row between adjacent rows. The coupling of the movable rod 38 with the travel multiplier 35 allows to obtain a lever 36 capable of increasing the travel of each of the cutting groups 17, 18 against a relatively reduced travel of the actuator 39. The actuation of the one or more motors 19 mounted on the first and / or second cutting group 17 and / or 18 drives in cascade the plurality of rotors 21, kinematically associated with each other and with a respective plurality of cutting elements 20, i.e., the cutters 20a, each of which operates by obtaining a cut of the grass depending on the height H of the wheels 11 with respect to the location plane of the cutting groups 17, 18. At the end of the cutting operation, each of the groups 17, 18 is retracted and returned to a closed configuration, e.g. for storing the equipment 1 once the work is completed. Once closed, the equipment 1 can be lifted by the lifting arms 3 for easy transport.

[0059] The invention thus achieves its intended purpose, providing a cutting equipment 1 that optimises grass cutting in the inter-row lanes of agricultural and forestry crops.

Claims

CLAIMS1. Grass-cutting equipment (1) applicable to a self-propelled vehicle (2), comprising:- a main frame (5);- a connection system (60) to the self-propelled vehicle (2) for moving the equipment (1) in an advance direction (A);- at least one cutting element (20);- at least one cutting group (17, 18) configured to support the at least one cutting element (20) in a work position, the at least one cutting group (17, 18) being mounted on the main frame (5) in a translatable manner along a translation direction (T) which is transverse to the advance direction (A);- a movement device (61) for the at least one cutting group (17, 18) in the translation direction (T), the movement device (61) comprising a linear actuator (39), characterised in that the movement device further comprises a travel multiplier (35) of the linear actuator (39) interposed between the linear actuator (39) and the corresponding cutting group (17, 18).

2. Equipment (1) according to claim 1, wherein the travel multiplier (35) comprises a lever mechanism (36) connected to the corresponding at least one cutting group (17, 18), to a fulcrum (37) on the main frame (5) and to the linear actuator (39) so as to move the at least one cutting group (17, 18) in the translation direction (T), preferably wherein the lever (36) forms a lever of the second or third type with the linear actuator (39).

3. Equipment (1) according to claim 2, wherein the lever (36) is hinged to the main frame (5) in the region of a first end thereof and is secured to the at least one cutting group (17, 18) in the region of a second end thereof, the linear actuator (39) being connected to the lever (36) in the region of an intermediate position of the lever.

4. Equipment (1) according to claim 2 or 3, wherein the lever (36) is secured to the at least one cutting group (17, 18) through a system with a slot (40) and pin (50) which is engaged in a sliding manner in the slot (40), preferably wherein the lever (36) has the slot (40) and the at least one cutting group (17, 18) has the pin (50), or vice versa.

5. Equipment (1) according to one or more of the preceding claims, wherein each cutting group (17, 18) is mounted on at least one guide (12, 13) through a respective slider (16), preferably wherein a pair of guides (12, 13) and relevant sliders (16) are provided for each cutting group (17, 18).

6. Equipment (1) according to one or more of the preceding claims, wherein there are at least two cutting groups (17, 18), at least one of which can be moved in translation.

7. Equipment (1) according to claim 6, wherein the cutting groups (17, 18) are actuated by respective linear actuators (39) independently.

8. Equipment (1) according to one or more of the preceding claims, wherein each cutting group (17, 18) comprises a lateral extent sensor (28) for protection in the event of collision during the opening of the equipment (1).

9. Equipment (1) according to one or more of the preceding claims, wherein each cutting group (17, 18) comprises at least one motor (19) which actuates a respective rotor (21) which carries a respective cutter (20a), preferably wherein each cutting group (17, 18) comprises a plurality of rotors (21) which are connected to the at least one motor (19) and which carry respective cutters (20a).

10. Equipment (1) according to claim 9, wherein the at least one motor (19) is connected in cascade to the plurality of rotors (21).

11. Equipment (1) according to claim 10, wherein the last rotor (21) of the cascade is provided with a sensor (25) which controls the rotation speed thereof.

12. Equipment (1) according to one or more of claims 9 to 11, wherein there is provided for each of the rotors (21) a driven shaft (27) and a scraper (26) which is mounted tangentially relative to the shaft (27).

13. Equipment (1) according to one or more of the preceding claims, comprising one or more wheels (11) for support on the ground, which are connected to the main frame (5).

14. Equipment (1) according to claim 13, comprising a detection system which is configured to detect the support of the wheels (11) on the ground.

15. Equipment (1) according to claim 13 or 14, wherein the wheels (11) are connected to the main frame (5) in an adjustable manner by way of an adjustment device (62) which is configured to adjust the height (H) of the wheels (11) with respect to the location plane ofthe at least one cutting element.

16. Equipment (1) according to one or more of claims 13 to 15, wherein the connection system (60) is connected to the main frame (5) at the opposite side with respect to the wheels (11).

17. Equipment (1) according to one or more of the preceding claims, wherein the connection system (60) comprises a three-point hitch (4), preferably of the carried or semi-carried type.

18. Self-propelled vehicle (2) with autonomous guiding, comprising a lifting device (3) to which the grass-cutting equipment (1) according to one or more of the preceding claims is applied.

Images