The invention relates to an agricultural machine frame according to the preamble of patent claim 1 for use in an agricultural machine. Such machine frames are readily used in soil cultivation devices or sowing machines, but also as a distributing rod assembly, for example, on a field sprayer. The machine frame thereby consists of a center part, which serves as a hitch or as an attachment on a vehicle or a running gear, as well as at least two lateral parts, which extend laterally from the center frame and can be folded from an extended working position into a compact transport position. The European patent specification EP 0 878 118 B1 describes the foldable machine frame of a rotary harrow for soil cultivation. On a center machine frame two booms are pivotably attached as lateral parts, on which in each case a rotary harrow half is suspended. About a pivot axis the two booms can in each case be hydraulically folded up by means of a hydraulic cylinder, which is movably arranged between the center frame and lateral part, from a wide, horizontal position, namely the working position, to a more narrow, vertical position, namely the transport position. The two hydraulic cylinders are thereby structurally integrated in the center frame, so that above the center frame other assemblies such as a gearbox or hopper can be arranged in a space-saving and compact manner. The PCT application WO 2012/170 548 also shows, for example, in FIG. 6 a machine frame of a soil cultivation machine with a center frame and lateral parts hinged thereon. By means of hydraulic cylinders, which mechanically connect only the lateral parts with one another in a cost-saving manner, both lateral parts can also be transferred from a horizontal working position into a vertical transport position. In contrast to the preceding patent specification, in which the pivoting movement is, of course, damped by hydraulic line resistances, in the present PCT application during a folding process a free and indefinite pivoting of the lateral part is possible, in that in the case of a somewhat angled position one lateral part falls down and the other is pulled upwards via the coupled hydraulic cylinder. Thus, machine damages and accidents can be caused.
The problem addressed by the invention is to provide a foldable, compact and cost-effective machine frame, which eliminates the previously mentioned disadvantages. This problem is solved by the features of the characterizing part of Claim 1.
By fixing the cylinder assembly in its lateral movement to the center frame the pivoting movement of the lateral parts takes place hydraulically damped via the cylinder assembly, which with its respective piston rods connects the right and left lateral parts with one another and through the piston movement causes the pivoting of the lateral parts. The absorption or support of the resulting, lateral damping forces thereby takes place in the center part by a limiting means, which is arranged between the center part and the cylinder assembly. Only one of six degrees of freedom of the cylinder assembly or its cylinder tube requires locking.
Advantageously, one hinges the cylinder assembly with at least one movable transverse control arm, known also as a Panhard rod, which is arranged hingedly between the center frame and the cylinder assembly. The active line runs thereby approximately parallel to the cylinder longitudinal axis, in order to reduce lateral cylinder movements relative to the center plane to a minimum.
In a further form of the invention the limiting means is depicted as a combination of a projection and a connecting-link, for example a pin or bolt, which runs in a elongate hole preferably vertically movably up and down.
If the lateral flanks of the stop connecting-link, which guide the pin or bolt, are formed non-parallel to the upright center plane of the center frame, for example, in an X-, diamond-, oval- or triangle shape, then the cylinder assembly depending on the lever configurations of the lateral parts can be applied depending on the end position with more or less lateral guide play, for example, with zero play in the transport position and an enlarged play in the working position, in order to make possible a relative movement of the lateral parts to the center part to compensate for terrain unevennesses. The stop projection and/or the stop connecting-link can be provided with elastic stop surfaces, in order to absorb bumps resiliently or in a damping manner.
Thereby at least one stop projection of the hydraulic cylinder assembly and the connecting-link is assigned to the center frame as a recess. The cylinder assembly can also be filled with at least one vertical groove, in which one or a plurality of pins or projections secured on the frame side engage and impede the cylinder assembly preferably without play in its movement laterally to the center plane.
By arrangement of the hydraulic cylinder assembly underneath the hinged axes of the center frame a free installation space is produced above the center frame, for example, for the arrangement of a gearbox or for containers for receiving operating substances of the agricultural devices or of items to be outputted. At the same time the hydraulic pressurization takes place for starting a folding movement on the piston head side, whereby in contrast to pulling cylinders, which are acted upon on the piston ring side, a smaller, space-saving and cost-effective piston- and cylinder diameter is required.
If one arranges an intermediate wall between the right and the left piston unit in the cylinder tube, then the movement of the piston units into the cylinder interior is limited symmetrically to a minimum installation dimension.
Preferably the intermediate- or center wall thereby protrudes at least partially elevated from the contour of the cylinder tube to form a projection, which together with a connecting-link of the center frame guides the cylinder assembly laterally. The reverse case is also conceivable in that the intermediate- or center wall is equipped with a groove and the center frame at least with one guide pin.
If one provides the center wall with further through-passages, preferably boreholes, the cylinder chambers can in the simplest manner be connected with one another or with externally located lines, in order to connect the hydraulic cylinder assembly to a pressure supply.
By installing further, preferably adjustable pivot stops defined end positions of the pivoting movements of the lateral parts are reached, wherein the hydraulic cylinder group may exceed minimum or maximum installation dimensions, which promotes a reuse in the modular system. At the same time the tolerance requirements of the limiting means are reduced for the lateral fixing of the cylinder assembly.
The invention is characterized in particular in that by installing a double piston cylinder between the pivot levers of a right and a left frame half, which in each case pivot about the center part of an agricultural machine frame, the piston forces within the cylinder assembly are largely mutually supported. A free, undefined striking back and forth of the right or left frame halves during the folding process is reliably prevented with low storage outlay by limiting the lateral movement of the cylinder assembly and its cylinder tube relative to the center part of the machine frame. In contrast to the rigidly fastened cylinder tube in the center part, which would move the lateral parts via further coupling tabs, the present hydraulic cylinder assembly remains nearly free of any radial forces, which strain the seals and piston guides.
Further details and advantages of the subject matter of the invention result from the following description and the associated drawings, in which an embodiment is depicted with the details and individual parts necessary for this purpose.
Instead of hydraulic cylinders other control elements can also be used passively or actively.
If one transforms the described frame system about one of its main axes, the system can also be used horizontally.
Reference signs not cited can be used analogously to the other figures and their descriptions.
Number | Date | Country | Kind |
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10 2015 118 354.4 | Oct 2015 | DE | national |
Filing Document | Filing Date | Country | Kind |
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PCT/DE2016/100505 | 10/27/2016 | WO | 00 |