Agricultural implement

Abstract

The present invention relates to an agricultural implement for soil cultivation, said implement comprising: a frame (3) which has at least one tool frame (4); a plurality of soil tools (5), in particular harrow tines, which are pivotably mounted on the at least one tool frame (4); and a pretensioning device (7) for pretensioning the soil tools (5) by means of a pretensioning force, the pretensioning device (7) having at least two fluid-filled pretensioning elements (8), each pretensioning element having a piston rod (10) connected to at least one piston chamber (9), and each piston rod (10) being associated with at least one soil tool (5). According to the invention, the piston rods (10) of the at least two pretensioning elements (8) are positioned next to one another, in particular directly next to one another, in a cylinder housing (11), and the piston chambers (9) of the piston rods (10) can be fluidically connected to one another.

Description

[0001] Agricultural implement

[0002] The present invention relates to an agricultural implement for soil cultivation.

[0003] Agricultural soil cultivation uses a variety of tools that can be attached to or mounted on a tractor. For mechanical weed control, tine harrows or hoe harrows are typically used. These harrows are guided close to the surface of the soil to be worked, mechanically pulling out weeds and / or covering them with soil. These harrows are often arranged in several rows, side by side.

[0004] A generic soil tillage implement with tine harrows as soil tillage tools is disclosed in DE 202012004337 U1. The tine harrows are pivotably mounted on a support frame and each preloaded against a stop by a preload spring. The preload force of the preload springs can be adjusted in groups by an operator of the soil tillage implement. Each preload spring is formed from two springs connected in series, whereby upon deflection of the associated harrow tine, a first spring is initially activated, followed by a second spring after a certain deflection. The force acting on the tines and thus during soil tillage is not constant due to the spring characteristics alone and varies depending on the deflection of the harrow tines, which can lead to uneven soil tillage.EP1961283B2 also discloses a soil tillage implement for cultivating the soil of cultivated plants, comprising a plurality of harrow tines pivotably mounted on a support frame and an adjusting device associated with the harrow tines, by means of which the preload of the spring-loaded harrow tines can be centrally adjusted. To enable quick and easy adjustment of the preload of the harrow tines, even during cultivation, the adjusting device has an electric or hydraulic actuator controllable by a control unit. The spring associated with each harrow tine makes assembly and, in particular, maintenance of the implement complex. The device for adjusting the preload requires additional installation space and further increases the weight of the implement.

[0005] In a soil tillage implement with multiple harrow tines disclosed in EP 3738419 A1, the harrow tines are each attached to levers pivotably mounted on supports on the support frame. A pneumatic cylinder is arranged on each harrow tine for pre-tensioning. Due to the large number of pneumatic cylinders, the implement's pneumatic system is quite extensive and complex, making both assembly and maintenance difficult.

[0006] It is therefore the object of the present invention to provide an agricultural implement which eliminates at least some of the disadvantages mentioned above.

[0007] The object is achieved by a working device according to the features of claim 1. Advantageous embodiments of the invention are specified in the subclaims. An agricultural working device for soil cultivation with a frame which comprises at least one tool frame, a plurality of soil tools, in particular harrow tines, pivotably arranged on the at least one tool frame, and a pretensioning device for pretensioning the soil tools by means of a pretensioning force, wherein the pretensioning device has at least two fluid-filled pretensioning elements, wherein each pretensioning element has a piston rod connected to at least one piston chamber, and a piston rod is assigned to at least one soil tool.According to the invention, the piston rods of the at least two prestressing elements are arranged, in particular directly, next to one another in a cylinder housing and the piston chambers of the respective piston rods can be fluidically connected to one another.

[0008] The fluid-filled preloading elements of the preloading device can be pressurized with a fluid in the form of oil or air, which can cause a corresponding movement of the piston rods. Each preloading element can have a piston chamber which is fluidically connected to the piston rod of the preloading element. The piston chambers of the at least two fluid-filled preloading elements can be fluidically connected, which can be achieved, for example, by a connecting line or by the piston chambers being designed jointly as one piston chamber which extends over the at least two preloading elements. Piston chambers or several preloading elements can form a common piston chamber. A fluidic connection is understood to mean that, for example, a pressure change of the fluid in one piston chamber can lead to a corresponding pressure change in the other piston chambers connected to this piston chamber.The piston rods of the at least two preloading elements can be arranged in a common, in particular the same, cylinder housing. The piston rods can each be arranged and / or guided in a cylinder formed by a cylinder housing. The ground tools can be directly or indirectly operatively connected to the preloading elements, in particular to the piston rods of the preloading elements, so that a movement of the piston rods can lead to a displacement of the ground tools.

[0009] Thanks to the fluid-filled pre-tensioning elements, the pre-tensioning force acting on the soil tools can remain essentially constant over the travel path of a harrow tine on the soil. This also allows the vertical contact force of the harrow tines to be kept essentially constant over the travel path on the soil, enabling improved soil cultivation. Furthermore, the arrangement of the piston rods in a common cylinder housing eliminates many components such as springs and spring assemblies, thus simplifying assembly and maintenance of the implement. The clearer arrangement of the pre-tensioning elements provides the operator of the soil cultivation implement with a better view of the soil tools and the work results.Furthermore, the arrangement of the pre-tensioning elements and piston rods, in particular in a cylinder housing, offers an improved arrangement of the pre-tensioning elements and thus of the pre-tensioning device with respect to the center of gravity of the working device.

[0010] The cylinder housing is preferably designed in one piece or in multiple parts, with piston chambers in the cylinder housing being designed to be pressurizable to the same or different degrees. A cylinder housing can be designed in the form of a cylinder housing beam which has an elongated extension parallel to a frame or tool frame of the work device. A multi-part cylinder housing can be composed of multiple cylinder housing parts, each with at least one piston chamber and at least one piston rod. In this case, a prestressing element with its associated piston rod can form a cylinder housing part. The piston chambers of the cylinder housing parts can be fluidically connected to one another, with, for example, pushing one piston rod into the piston chamber causing the other piston rods connected to the piston chamber to extend.A single-piece cylinder housing offers the advantage of reduced assembly effort. With a multi-part design, the individual cylinder housing components can be uniformly constructed, thus enabling a modular design of the preloading device.

[0011] In a preferred embodiment, the pretensioning device is designed such that a controlled movement of a pretensioning element, in particular a piston rod of a pretensioning element, in two opposite directions is possible. This has the advantage that both compressive and tensile forces can be generated by the pretensioning element or the piston rod and transmitted to a ground tool. This controlled movement in opposite directions thus enables a corresponding movement of at least one ground tool connected to the pretensioning element.

[0012] Advantageously, a preloading element is designed in the form of a double-acting cylinder, with a second piston chamber being provided in addition to the piston chamber. This second piston chamber can be designed in a ring shape around the piston rod. Several second piston chambers can be fluidically connected to one another and designed to be pressurized with a fluid, thereby enabling a controlled, uniform movement of the thus coupled preloading elements.

[0013] In a preferred embodiment, the cylinder housing is formed by the frame, in particular at least one tool frame, wherein the frame, in particular the at least one tool frame, forms a piston chamber. The frame or the at least one tool frame can accommodate and guide the piston rods of the preloading elements. The frame or the at least one tool frame can be designed as a closed profile, for example in the form of a U-profile closed with a plate for receiving and guiding the piston rods. The piston chamber formed by the frame or the at least one tool frame can be effective for all preloading elements arranged on this frame or tool frame and their piston rods, whereby a common control of the piston rods connected to this piston chamber can be enabled by pressurizing and / or changing the pressure of the fluid in the piston chamber.The piston chamber can also be designed as a pressurizable fluid reservoir, for example in a section free of prestressing elements.

[0014] In a further preferred embodiment, the pretensioning device comprises at least one connecting element, by which at least one ground tool is operatively connected to a pretensioning element, in particular a piston rod of a pretensioning element. A ground tool can be indirectly connected to a pretensioning element and / or a piston rod by a connecting element in order to enable a controlled pivoting movement of the ground tool depending on a movement of the piston rod of the pretensioning element. A connecting element can be designed in the form of a rod for transmitting tensile forces and compressive forces or in the form of a cable for transmitting tensile forces.

[0015] Furthermore, at least two ground tools, which are each operatively connected to one, in particular the same, prestressing element via a connecting element, are advantageously coupled via a web of the prestressing device arranged on the prestressing element side. The connecting elements of the ground tools can each be articulated to the web at opposite ends, wherein the web can be centrally connected to the prestressing element, in particular the piston rod of the prestressing element. As a result, at least two ground tools can be prestressed by one, in particular the same, prestressing element. During a movement of one of the ground tools, for example, directed upwards away from the ground, this movement can be transmitted to the web via the connecting element and lead to a pivoting movement of the end of the web assigned to this ground tool around the opposite end assigned to the other ground tool.This pivoting movement can lead to a corresponding movement of the preloading element connected to the web, particularly its piston rod, thereby preventing movement of the other ground tools. The arrangement of the web and the associated connecting elements and piston rod essentially acts like a horizontally arranged bogey wheel arrangement.

[0016] Preferably, a piston guide is provided to guide each piston rod, wherein the piston guide is arranged, in particular detachably, in the cylinder housing and / or is formed integrally with the cylinder housing. In addition to guiding a piston rod, a piston guide can also serve to seal the piston chamber from the environment. A guide for the piston rod can be formed integrally with the cylinder housing, for example, directly in the frame or tool frame. This offers the advantage of low assembly effort. A piston guide can also be designed as a separate component and arranged on or in the cylinder housing, which can enable simplified maintenance, for example by replacing the piston guides.

[0017] In a preferred embodiment, the piston rods are arranged next to one another in one plane or in several substantially parallel planes, wherein the piston rods are displaceable substantially in one working direction and / or substantially counter to the working direction. Displacement of the piston rods can cause a change in the effective preload force in the associated ground tools. The piston rods can be arranged next to one another in one or more planes, wherein these planes can, for example, also be arranged rotated relative to one another. The planes can, for example, be arranged horizontally, vertically, or at an angle to the working direction and / or the ground. In conjunction with a beam-shaped cylinder housing, the preload elements and piston rods can be arranged on the frame in a space-saving manner.By arranging the piston rods in, particularly parallel, planes, assembly of the pretensioning device can be simplified.

[0018] In a further preferred embodiment, the pretensioning device is arranged and / or guided at least partially below, within, and / or above the frame, in particular the tool frame. This enables a space-saving arrangement on the implement, which also provides an improved view of the ground tools and can further protect the pretensioning device from damage during operation.

[0019] In a particularly preferred embodiment, the pretensioning device is designed and constructed such that a plurality of pretensioning elements can be actuated individually or in groups. Jointly actuated pretensioning elements, in particular their piston rods, can have a common piston chamber, the fluid of which can be pressurized. The pretensioning elements can be arranged in a common cylinder housing with separately controllable piston chambers. It is also conceivable for the cylinder housing to be constructed in several parts, wherein the piston chambers of the cylinder housing parts can be pressurized separately from one another. This allows the pretensioning elements connected to a common piston chamber to be controlled jointly.This has the advantage that individual rows of soil tools, especially tine rows, can be loaded separately, which means that, for example, individual rows or sections can be brought into contact with the soil or lifted out.

[0020] Particularly advantageously, at least one return element counteracting the pretensioning force is provided, wherein a return element is assigned to at least one pretensioning element, in particular a piston rod and / or a ground tool. A return element can generate a return force which counteracts a pretensioning force of the pretensioning element. The return force can act directly on a piston rod of the pretensioning element and / or a ground tool assigned to the pretensioning element. As a result, if the return force is greater than the pretensioning force, the pretensioning element and in particular its piston rod can be returned, whereby a ground tool can be raised, for example, from ground engagement into a transport position.A return element can be designed, for example, in the form of an elastic ring, a spring, in the form of a second piston rod counteracting the first, or a double-acting piston rod.

[0021] Preferably, the return element of a piston rod is designed in the form of an elastic element or a spring and is arranged on the piston rod inside or outside the piston chamber. The return element outside the piston chamber can be designed, for example, in the form of an elastic ring arranged on the frame. Within the piston chamber, the return element can be designed, for example, in the form of a spring arranged around the piston rod, whereby the return element can be arranged in a manner protected from external influences.

[0022] In a preferred embodiment, the pretensioning device has at least one fluid reservoir, in particular a pressure reservoir, at least one control valve, a pump, a fluid coupling for connection to a towing vehicle, and / or a control unit for controlling at least one pretensioning element.

[0023] Further details of the invention can be found in the figures and the description of the figures, which show a preferred embodiment of the invention.

[0024] They show:

[0025] Fig 1 : a perspective view of a working device with each on a

[0026] Tool frame arranged floor tools; Fig. 2: a perspective view of a beam-shaped cylinder housing of the connecting elements from Fig. 1;

[0027] Fig. 3: a sectional side view of a tool frame with a prestressing element arranged thereon according to Fig. 1;

[0028] Fig. 4: a side view of a substantially above a

[0029] Pretensioning device arranged in the tool frame; and

[0030] Fig. 5: a plan view of a prestressing device with connecting elements connected via webs.

[0031] Figure 1 shows an agricultural implement 1 for soil cultivation with a frame 3, on which a coupling device 2 for connecting the implement 1 to a towing vehicle (not shown) is arranged. The frame 3 comprises a plurality of tool frames 4 arranged parallel to a working direction, with a plurality of soil tools 5 being pivotably arranged on each tool frame 4 at a distance from one another. The soil tools 5 in the form of harrow tines are each pivotally connected to the frame 3, in particular the tool frame 4, at a bearing point 6. The soil tools 5 are shown in a lowered soil cultivation position and can be raised into a transport position in which the soil tools 5 essentially rest against an underside of the tool frames 4. For soil cultivation, the soil tools 5 must act on the soil with at least a certain force, for example to pull out unwanted weeds.For this purpose, the work device 1 has a pretensioning device 7, by means of which the ground tools 5 can be subjected to an adjustable pretensioning force. The pretensioning device 7 has at least two fluid-filled pretensioning elements 8, wherein the fluid can be air or a liquid such as oil. The work machine 1 shown has a plurality of fluid-filled pretensioning elements 8, wherein each pretensioning element 8 has a piston rod 10 connected to at least one piston chamber 9, and a piston rod 10 is each assigned to at least one ground tool 5. The ground tools 5 are each connected to a piston rod 10 of a pretensioning element 8 via connecting elements 14.

[0032] According to the invention, the piston rods 10 of the pretensioning elements 8 are arranged side by side in a cylinder housing 11, and the piston chambers 9 of the respective piston rods 10 are fluidly connected to one another. The pretensioning device 7 can be connected to the towing vehicle (not shown) via a fluid coupling 21 and supplied and / or controlled via its fluid device. The illustrated implement 1 has a fluid reservoir 18 arranged on the frame 3, which is connected to a control unit 22, a pump 20, and control valves 19 for controlling the pretensioning device 7.

[0033] The preload elements 8 (Fig. 2) and their piston rods 10 are arranged side by side in a common, beam-shaped cylinder housing 11 in one plane. In the example shown, the cylinder housing 11 is composed of several cylinder housing parts 12. However, the cylinder housing 11 can also be formed in one piece. The piston rods 10 are each guided by a piston guide 16 inserted into the cylinder housing 11 and are fluidically connected to a common piston chamber (not shown), whereby a change in the pressure of the fluid in the piston chamber 9 results in a joint movement of the piston rods 10 of the preload elements 8 connected to the piston chamber 9. The piston chamber 9 can be connected, for example, to the fluid reservoir 18 via a connection 23 and can be pressurized via the pump 20.

[0034] Fig. 3 shows a sectional side view of the pretensioning device 7. The cylinder housing 11 has a fluid-filled piston chamber 9 on its inside, through which the piston rod 10 of the pretensioning element 8 can extend out of the cylinder housing 11 when pressure is applied. The ground tools 5 can be raised via the illustrated connection of the piston rod 10 to the ground tools 5 below the tool frame 4 by means of a connecting element 14. The ground tools 5 can be subjected to a pretensioning force by reducing the pressure in the piston chamber 9 or by increasing the pressure in a second piston chamber 13, which is formed annularly around the piston rod 10. The second piston chamber 13 can also act like a return element 17 on the piston rod 10 or the pretensioning element 8. The piston rod 10 is guided in the piston guide 16, which is inserted into the cylinder housing 11 as a separate component.The piston guide 16 could also be designed in one piece with the cylinder housing 11.

[0035] A side view of a pretensioning device 7 and floor tools 5 with return elements 17 is shown in Fig. 4. The connecting elements 14, which connect the floor tools 5 to the pretensioning element 8, are arranged above the tool frame 4. A return element 17 in the form of an elastic ring is arranged on each of the floor tools 5 mounted in bearing points 6. This return element 17 extends from a connecting-element end of the floor tool 5 around the tool frame 4 to the bearing point 6 and is fastened there, for example, in a form-fitting manner. As a result, the floor tools 5 can be raised by means of the return elements 17 when the pretensioning force decreases, for example, into a transport position on the tool frame 4.

[0036] The pretensioning device shown in Fig. 5 is shown in a plan view, wherein two ground tools 5 are each connected to a pretensioning element-side web 15 via connecting elements 14. The ground tools 5 are each pivotally connected to the web 15 at opposite ends thereof. Essentially in the center of the web 15, the web is pivotally connected to the piston rod 10 of the associated pretensioning element 8. When the pretensioning element 8 and the piston rod 10 are actuated, both ground tools 5 can be subjected to a pretensioning force or, for example, raised in a transport position. If one of the two ground tools 5 is deflected essentially vertically, this force is transmitted to the web 15 via the connecting element 14, which can cause the web 15 to pivot about the bearing of the other ground tool 5.In this case, the piston rod 10 is also moved due to its connection to the web 15, for example, it is pulled out of the cylinder housing 11. The other base tool 5, around whose end of the web 15 the pivoting has taken place, experiences essentially no displacement and thus no change in its preload force.

[0037] Reference symbol

[0038] Working device A Working direction Coupling device Frame Tool frame Floor tool Bearing point Pre-tensioning device Pre-tensioning element Piston chamber Piston rod Cylinder housing Cylinder housing part Second piston chamber Connecting element Web Piston guide Reset element Fluid reservoir Control valve Pump Fluid coupling Control unit Connection

Claims

Claims: Agricultural implement for soil cultivation with a frame (3) comprising at least one tool frame (4), a plurality of soil tools (5), in particular harrow tines, pivotably arranged on the at least one tool frame (4), and a pretensioning device (7) for pretensioning the soil tools (5) by means of a pretensioning force, wherein the pretensioning device (7) has at least two fluid-filled pretensioning elements (8), wherein each pretensioning element (8) has a piston rod (10) connected to at least one piston chamber (9), and each piston rod (10) is assigned to at least one soil tool (5), characterized in that the piston rods (10) of the at least two pretensioning elements (8) are arranged, in particular directly, next to each other in a cylinder housing (11), and the piston chambers (9) of the respective piston rods (10) are fluidically connectable to each other.Working device according to claim 1, characterized in that the cylinder housing (11) is designed in one piece or in multiple parts, wherein piston chambers (9) in the cylinder housing (11) are designed to be pressurized equally or differently. Working device according to claim 1 or 2, characterized in that the preloading device (7) is designed such that a controlled movement of a preloading element (8), in particular a piston rod, is possible. (10) of a preloading element (8) is enabled in two opposite directions. Working device according to one of the preceding claims, characterized in that a preloading element (8) is designed in the form of a double-acting cylinder, wherein, in addition to the piston chamber (9), a second piston chamber (13) is provided. Working device according to one of the preceding claims, characterized in that the cylinder housing (11) is formed by the frame (3), in particular at least one tool frame (4), wherein the frame (3), in particular the at least one tool frame (4), forms a piston chamber (9). Working device according to one of the preceding claims, characterized in that the preloading device (7) comprises at least one connecting element (14) by which at least one base tool (5) is operatively connected to a preloading element (8), in particular a piston rod (10) of a preloading element (8).Working device according to one of the preceding claims, characterized in that at least two ground tools (5), which are operatively connected to a pretensioning element (8) via a connecting element (14), are coupled via a web (15) of the pretensioning device (7) arranged on the side of the pretensioning element.

8. Working device according to one of the preceding claims, characterized in that a piston guide (16) is provided for guiding a piston rod (10), wherein the piston guide (16) is arranged in the cylinder housing (11) and / or is formed integrally with the cylinder housing (11), in particular detachably.

9. Working device according to one of the preceding claims, characterized in that the piston rods (10) are arranged side by side in one plane or in several substantially parallel planes, wherein the piston rods (10) are displaceable substantially in a working direction (A) and / or substantially against the working direction (A).

10. Working device according to one of the preceding claims, characterized in that the pretensioning device (7) is arranged and / or guided at least partially below, inside and / or above the frame (3), in particular tool frame (4).

11. Working device according to one of the preceding claims, characterized in that the pretensioning device (7) is designed and constructed in such a way that several pretensioning elements (8) can be actuated individually or in groups. Working device according to one of the preceding claims, characterized in that at least one return element (17) counteracting the preload force is provided, wherein a return element (17) is associated with at least one preload element (8), in particular a piston rod (10) and / or a ground tool (5). Working device according to one of the preceding claims, characterized in that the return element (17) of a piston rod (10) is designed in the form of an elastic element or a spring and is arranged inside or outside the piston chamber (9) on the piston rod (10).Working device according to one of the preceding claims, characterized in that the pretensioning device (7) has at least one fluid accumulator (18), in particular a pressure accumulator, at least one control valve (19), a pump (20), a fluid coupling (21) for connection to a towing vehicle, and / or a control unit (22) for controlling at least one pretensioning element (8).

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