Abstract
A cutting device for agricultural harvesters has a conveying channel and pivotably supported cutting knives arranged in a row on a frame. The cutting knives project in the cutting position into the conveying channel. A conveying member with conveying tines, rotatingly driven about a horizontal axis, interacts with the cutting knives for comminuting crop. Individual adjusting devices, each associated with one cutting knife, yieldingly support the cutting knives in the cutting position. A knife switching device is provided to move the cutting knives from the inoperative position into the cutting position. With a preselecting device a desired group of cutting knives can be selected that is pivoted into the cutting position upon activation of the knife switching device. The preselecting device is activatable with reduced force expenditure by eliminating resistances, caused by adjusting and connecting devices of the knife switching device, when preselecting the desired group of cutting knives.
Claims
1. A cutting device for agricultural harvesting machines, the cutting device comprising a conveying channel; cutting knives arranged in at least one row adjacent to each other on a frame and pivotably supported on the frame, wherein the cutting knives comprise an active cutting position and an inoperative position, wherein, in the active cutting position, the cutting knives project into the conveying channel; a conveying member arranged at the conveying channel and configured to be rotatingly driven about a horizontal axis oriented transverse to a travel and working direction of the cutting device, wherein the conveying member comprises conveying tines; the cutting knives and the conveying member interacting with each other for comminuting a crop; individual adjusting devices, each associated with one of the cutting knives, respectively, and each comprising a tensioning device configured to yieldingly support the cutting knives individually in the active cutting position; a knife switching device operatively connected to the cutting knives so as to move the cutting knives from the inoperative position into the active cutting position; a preselecting device configured to preselect a desired group of the cutting knives, the desired group of the cutting knives pivoted into the active cutting position upon activation of the knife switching device; wherein the cutting device has an inoperative position, wherein in the inoperative position of the cutting device the preselecting device is configured to be activated with reduced force expenditure by decoupling the preselecting device from the knife switching device and from the tensioning devices during a preselecting movement of the preselecting device carried out to preselect the desired group of the cutting knives so that the preselecting device is free of forces caused by the knife switching device and the tensioning devices.
2. The cutting device according to claim 1, wherein the knife switching device carries out a pivot movement when actuated.
3. The cutting device according to claim 1, wherein the knife switching device, when actuated, at least temporarily performs during its movement course additional forcibly guided functions by mechanical contact of a contact edge of the knife switching device with parts of the tensioning devices.
4. The cutting device according to claim 1, wherein the preselecting device comprises at least five switching positions.
5. The cutting device according to claim 1, wherein the preselecting device is a switching shaft with cams.
6. The cutting device according to claim 1, wherein the preselecting device comprises individual preselecting devices, each associated with one of the cutting knives.
7. The cutting device according to claim 5, wherein the individual preselecting devices are cam discs provided with contact cams.
8. The cutting device according to claim 7, wherein the cams discs are variably supported on a profiled shaft.
9. The cutting device according to claim 1, wherein the cutting knives have a spacing relative to each other and the spacing defines the shortest theoretical section length of the crop when cut by the cutting knives and the shortest theoretical section length is in a range from 15 mm to 45 mm.
10. The cutting device according to claim 9, wherein the spacing and the shortest theoretical cutting length of the crop is in a range from 15 mm to 25 mm.
Description
BRIEF DESCRIPTION OF THE DRAWING
(1) The invention will be explained in the following with the aid of an embodiment shown in the drawings. Further details and advantages can be taken therefrom.
(2) FIG. 1 is a side view of a bale press as a whole with a cutting device.
(3) FIG. 2 is a perspective view of the cutting device according to the invention with surrounding components removed.
(4) FIG. 3 is a perspective individual representation of the preselecting device of the cutting device according to FIG. 2.
(5) FIG. 4 is a side view of the cutting device according to FIG. 2 in section illustration, wherein the cutting device is in inoperative position.
(6) FIG. 5 is a side view as in FIG. 4 wherein, however, the transition from the inoperative position to the operative position (active cutting position) of the cutting device is illustrated.
(7) FIG. 6 is a side view as in FIG. 4 wherein, however, the operative position of the cutting device is illustrated.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
(8) The bale press 1, illustrated in FIG. 1, is movable in the travel and working direction F across a field or a meadow and is supported on wheels 2, 3 relative to the ground. It is connectable by drawbar 4 with an agricultural tractor, not illustrated, wherein the drive action is realized by means of the power take-off of the tractor by means of a universal shaft 5. The bale press 1 comprises a pick-up device 6 by means of which the crop lying on the ground in swaths, for example, straw, hay or wilted green crop, can be picked up from the field or meadow. The pick-up device 6 in the illustrated embodiment is designed as a pick-up drum 8 of known configuration that is provided with tines 7. Transverse screw conveyors 9, 10 for reducing the width of the picked-up crop swath are associated with the pick-up drum 8. Downstream in the flow direction of the crop, a cutting device 11 adjoins the pick-up drum 8; the cutting device 11 is substantially comprised of a conveying member 14 embodied as a conveying and cutting rotor with conveying tines 13 protruding into a conveying channel 12, cutting knives 15, and strippers 16 arranged between the cutting knives 15. Downstream of the cutting device 11, the crop is conveyed by action of a conveying device 17 designed as a rake conveyor through a feed channel 18 and a pressing channel inlet opening 19 from below into the pressing channel 20 in which a reciprocating pressing piston 21 compresses the crop to dense square (parallelepipedal) bales. When a preselected length of the crop bales is reached, the bales are tied by tying material. For this purpose, only schematically indicated knotting devices 22 with respectively associated tying needles 23 are provided. In the illustrated embodiment, the cutting device 11 according to the invention is used on a bale press for producing square (parallelepipedal) crop bales. However, it is likewise also conceivable to employ the cutting device 11 according to the invention in a bale press for producing round bales or in a self-loading trailer.
(9) In FIG. 2, the cutting device 11 according to the invention is illustrated in more detail in a perspective enlarged illustration. The cutting device 11 of the embodiment as a whole is advantageously mounted on a frame 24 which, guided on guides of the bale press 1, can be pulled laterally out of the bale press 1 for servicing purposes. Clearly shown are two cutting knives 15 which, for illustration purposes, are illustrated in a completely extended pivoted operating position and in an intermediate position. The other cutting knives 15 of this cutting device 11 that is provided with very many knives are in the retracted pivoted inoperative position. The connector of the hexagon shaft 25 for the actuating lever of the preselecting device 26 is clearly shown as is the adjusting cylinder 27 of the knife switching device 28 and the spiral springs 29 of the tensioning devices 30.
(10) FIG. 3 shows in detail the preselecting device 26 comprised of switching discs 31 pushed onto the hexagon shaft 25 and in regard to their number and spacing are corresponding exactly to the number and spacing of the cutting knives 15 and thus extend across the entire width of the cutting device 11. The switching discs 31 have contact cams 32 which will be explained in detail in the following.
(11) FIG. 4 shows in a side view a section illustration of the cutting device 11. In this illustration, the different component groups and components of the cutting device 11 can be seen particularly well. FIG. 4 shows the cutting device 11 in its inoperative position. The knife switching device 28 has been pivoted about its pivot axis 33 in downward direction by retracting the adjusting cylinder 27 so that at the same time the pivot axis 34 of the tensioning lever 35 has been moved such that the upper free end of the tensioning lever 35 is located outside of the active area (circumcircle diameter) of the contact cam 32. Accordingly, in this position, the preselecting device 26 can be rotated easily in one direction without forces having to be overcome that would be acting on it through the tensioning levers 35, for example, by the spiral springs 29 of tensioning units 30. During pivoting of the knife switching device 28 into the inoperative position, the contact edge 36 of the transverse beam 37 of the knife switching device 28 has been moved against the tensioning levers 35 in the area below the pivot axis 34 and this effects forcibly, due to the connection of the tensioning levers 35 with the forks 38 of the tensioning units 30, the return pivot movement of the adjusting lever 39 which, in turn, causes the cutting knives 15 to dip into their inactive position.
(12) The additional FIGS. 5 and 6 show in the same view as FIG. 4 the embodiment of the cutting device 11 according to the invention in further operating positions.
(13) FIG. 5 represents the intermediate position during the switching process of the knife switching device 28 from the inoperative position (FIG. 4) into the operative (active cutting) position (FIG. 6) of the cutting device 11. By making a preselection, one or more contact cams 32 of the switching discs 31 of the preselecting device 26 are positioned opposite selected tensioning levers 35. The knife switching device 28 is then pivoted in counterclockwise direction so far about the pivot axis 33 that the tensioning levers 35 come to rest at the preselected contact cams 32. Upon further pivoting of the knife switching device 28, the pivot axis 34 of the tensioning levers 35 is moved also. This causes the tensioning levers 35, which are contacting the contact cams 32 with their upper end, to perform a movement of their lower end which is connected with the fork 38 of the tensioning unit 30 so that the tensioning unit 30 is pretensioned and the correlated cutting knife 15 is switched by means of the connected adjusting lever 39 into its active cutting position (FIG. 6).
(14) The tensioning levers 35 that are not in contact with a contact cam 32 of the preselecting device 26 move during this process below the preselecting device 26 into the empty space and cause no pretensioning of the tensioning units 30.
(15) In order to prevent rotation of the preselecting device 26, the latter is supported against a pivotable locking bar 40 which, upon rotation of the preselecting device 26 in clockwise direction for preselecting a group of knives 15, is lifted by the contact cams 32 and is returned by gravity into the arresting position.
(16) In FIG. 6, the end position of the switching process for activation of the preselected cutting knives 15 are illustrated. The selected cutting knives 15 are in the operative position (active cutting position) and are secured by spring pressure of the corresponding tensioning unit 30 relative to the correlated adjusting lever 39. In FIG. 6, the adjusting elements 35, 39 of the inactive cutting knives 15 are shown clearly in their inoperative position. Advantageously, in the cutting device 11 according to the invention, as can be seen in FIG. 6, the inactive tensioning units 30 remain completely unloaded in the operative position of the cutting device 11. Also, it is apparent that the pivot movement of the knife switching device 28 which provides simultaneously several functions is particularly advantageously in regard to the compact configuration of the cutting device 11 according to the invention.
(17) The cutting knives 15 have a spacing relative to each other that defines the shortest theoretical section length of the crop when cut by the cutting knives and the shortest theoretical section length is in a range from 15 mm to 45 mm, preferably in a range from 15 mm to 25 mm.
(18) The specification incorporates by reference the entire disclosure of German priority document 20 2014 006 083.5 having a filing date of Jul. 30, 2014.
(19) While specific embodiments of the invention have been shown and described in detail to illustrate the inventive principles, it will be understood that the invention may be embodied otherwise without departing from such principles.
