Corn picker and agricultural machine equipped with it

Abstract

A corn picker comprises at least one row unit, wherein the row unit includes a picking unit in which two picking rollers define a picking gap, and a chopping unit arranged below the picking unit to chop a stalk drawn through the picking gap, and a transmission unit comprising a first main shaft for driving the at least one picking unit and a second main shaft for driving the at least one chopping unit. The transmission unit (21) is arranged in a side wall of the corn picker (1) and comprises a drive shaft (26) driven by the first and second main shafts (46, 33), which runs in a common vertical plane with the first and second main shafts (46, 33).

Description

The present invention relates to a corn picker which, typically as a crop header or part of a crop header of a mobile agricultural machine, serves to cut off corn stalks near the ground and to separate the pistons therefrom. Such a corn picker and a agricultural machine equipped therewith are known from EP 2 936 963 B1.This conventional corn picker comprises a plurality of row units distributed in the width direction of the corn picker at a pitch corresponding to the row pitch of a corn crop to be harvested on a field, so that when the agricultural machine travels in the direction of the rows across the field, each row unit sequentially detects and cuts the stalks of a row. Each row unit comprises a picking unit with two picking rollers forming a picking gap. As the picking rollers draw a cut stalk through the picking gap, the pistons are stripped off; the stalk freed from the pistons is comminuted by a chopper unit arranged below the picking unit, and the chopped material obtained in this way is distributed on the field.At opposite ends of a rear side of the corn picker, a first drive connection and a second drive connection are provided which, in operation, are drivingly connected to a motor of a base unit of the agricultural machine. One of the drive connections drives the picking units via a common picker drive shaft extending in the transverse direction of the corn picker, while the other drives the picking units via a corresponding chopper drive shaft.By driving picking and chopping units separately from one another in this way, although-provided the base unit has a suitable gear mechanism between the motor and output connections coupled to the drive connections of the corn picker-different rotational speed ratios can be set between picking and chopping units, this is associated with considerable cost, weight and space requirements since two separate drive trains have to be implemented on the side of the corn picker; in addition, the two output connections spaced apart make it difficult to couple the corn picker to the base unit and to use corn pickers of different widths on a same base unit.It is an object of the invention to provide a corn picker which enables the simultaneous operation of picking and chopping units with little outlay in terms of costs, weight and installation space.According to one aspect of the invention, the object is achieved in that, in a corn picker having at least one row unit, wherein the row unit comprises a picking unit in which two picking rollers delimit a picking gap, and a chopper unit which is arranged below the picking unit in order to chop a straw which has been pulled through the picking gap, and a transmission unit which comprises a first main shaft for driving the at least one picking unit and a second main shaft for driving the at least one chopper unit, the transmission unit is arranged in a side wall of the corn picker and comprises a drive shaft which is drivingly connected to the first and the second main shaft and runs with the first and the second main shaft in a common vertical plane. Since only one common drive shaft is required for picking and chopping units, the establishment of a force-transmitting connection to the base unit and thus the attachment of the corn picker to the base unit is facilitated; the arrangement of the shafts in a common vertical plane enables a space-saving accommodation of the transmission in a side wall of the corn picker.In order to enable different speed ratios between picking and chopping units, a stepped transmission can be provided between the drive shaft and one of the main shafts, preferably the first main shaft.In order to realize the different shift stages in a compact installation space, the multi-stage transmission can comprise a plurality of pairs of wheels with mutually intermeshing wheels. In order to selectively allow or to prevent the torque flow via one of the pairs of wheels, at least one of the wheels of each pair of wheels can be switched over between a state coupled in a rotationally fixed manner to the shaft carrying it and a state rotatable relative to the shaft.If the stepped transmission comprises a countershaft, the pairs of wheels can each have a first wheel supported by the countershaft, while second wheels of the pairs of wheels are distributed over the drive shaft and the one main shaft. The torque transmission can then take place in two steps, from the input shaft to the countershaft and from this to the main shaft. The two-stage nature allows for widely varying gear ratios with small diameter differences between the wheels of each pair, which in turn allows for a compact design of the transmission. Preferably, two pairs of wheels are provided with wheels distributed on the input shaft and the countershaft or on the countershaft and the one main shaft, so that the stepped transmission forms a four-speed transmission.For a compact design of the transmission and in particular its space-saving accommodation in a side wall of the corn picker, it is further useful for the countershaft to run in the plane of the drive and main shafts.A transmission ratio of the stepped transmission should be remotely controllable electrically and / or hydraulically in order to make it possible to establish the transmission ratio from a driver's cockpit of a agricultural machine equipped with the corn picker, preferably when the machine is running during harvesting operation.For this purpose, a clutch can be arranged on a shaft between two wheels of different pairs of wheels and can be adjusted between two positions in which it couples one of the adjacent wheels to the shaft in a rotationally fixed manner. This shaft is preferably the countershaft. The usability of a same clutch for two pairs of wheels also contributes to the compactness of the transmission and to favorable manufacturing costs.In order to be able to prevent the operation of one of the units, typically the chopper unit, when not required, its main shaft can be decoupled from the drive shaft. If several series units are driven via the stepped transmission, their chopper units do not need to be individually shifted, but can all be deactivated to one stroke by decoupling their common main shaft.If at least one of the main shafts, optionally the second main shaft, is coupled to the drive shaft via an intermediate shaft, such decoupling can be effected by pivoting the intermediate shaft, in which case a wheel of the intermediate shaft is decoupled from the one main shaft and, as a result, the transmission of force between the intermediate shaft and the one main shaft is interrupted. By the pivoting movement taking place on a path coaxial to the other main shaft, the frictional connection between the other main shaft and the intermediate shaft can remain.If at least one wheel is replaceable in a pair of wheels that couple the intermediate shaft to the other main shaft, the transmission ratio between the input shaft and the main shaft can be modified by such replacement. In particular, if the intermediate shaft is pivotable as mentioned above, it is sufficient to change the transmission ratio by replacing a single wheel.The first main shaft may be coupled to a plurality of the picking units, typically all or a half of the picking units, via a picker output shaft extending in the width direction of the corn picker. In the same way, the second main shaft can be coupled to a plurality of the chopper units via a chopper output shaft running in the width direction of the corn picker.In order to drive a maize picker of large width, it may be expedient for a second gear unit to be provided in a second side wall of the maize picker and for each gear unit to be assigned a picker output shaft and a chopper output shaft. The output shafts of the two transmission units can be physically separated from one another; however, it is also conceivable for each transmission unit to engage one of two opposite ends of a contiguous output shaft.The invention further relates to an agricultural machine having a mobile base unit and a corn picker as described above, in which the drive shaft of the at least one transmission unit is coupled to an output connection, for example a power take-off shaft, of the base unit.Further features and advantages of the invention will become apparent from the following description of exemplary embodiments with reference to the appended figures. The following are shown: FIG. 1 is a schematic side view of a corn picker according to the invention mounted on a combine harvester; FIG. 2 shows the corn picker in a perspective view obliquely from behind; FIG. 3 shows a gearbox of the corn picker; FIG. 4 shows a schematic top view of a first model of the corn picker; and FIG. 5 shows a schematic top view of a second model of the corn picker.FIG. 1 shows schematically an agricultural machine, here a combine harvester, having a mobile base unit 2 and a corn picker 1 mounted at the front of the base unit 2, which is only shown in part. A row of guide hoods 4 widening in each case from the front tip 3 to the rear, similar to a half cone, is arranged along a front edge of the corn picker 1. Lateral flanks 5 of adjacent guide hoods 4 each delimit a crop receiving region which narrows towards the rear and into which, when the combine harvester travels in a direction of travel FR along rows of a corn crop on a field in order to harvest the corn, the corn stalks engage one after the other in order to be cut when the rear end of the crop receiving region is reached and to be pushed by endless conveyor chains 19 which rotate between deflecting rollers 10, 11 into a picking gap between two picking rollers 7.The picking rollers 7 are driven in rotation in opposite directions in order to pull the stalks downwards through the picking gap and thereby strip off the pistons hanging thereon at the edges of picking plates which extend on both sides of the picking gap between the conveyor chains 19 above and the picking rollers 7 below. The two picking plates and picking rollers, which each delimit a picking gap, form a picking unit.Wall plates 6 which slope away toward the picking gap hold the stripped pistons within the reach of the conveyor chains 19, so that the stripped pistons are pushed further rearward by the conveyor chains 19 into the capture range of a conveyor screw 8 extending transversely to the direction of travel FR. The conveying screw 8 is rotationally driven in order to push the pistons as far as an outlet 12 (see FIG. 2 ) in the middle of a rear wall 13 of the corn picker 1, from where they are conveyed further to a threshing unit inside the base unit 2.As the stalks pass down the picking gap, they are comminuted by a chopper unit 9 with rotating knives arranged below the picking rollers 7, and the obtained chopped material is scattered on the field.FIG. 2 shows the corn picker 1 in a view obliquely from behind. The outlet 12 can be seen in the middle of the rear wall 13, the row of tips 3 along a front edge of the corn picker 1 and side walls 14 running forward in the direction of travel from the ends of the rear wall 13, and a row unit 15 is situated in each case between two tips 3, each having a detection region 16 which narrows toward the rear, the picking unit 17 adjoining said row, and the chopper unit 9 concealed under the corn picker 1.On both sides of the outlet 12, drive connections 18 are arranged on the rear wall 13, which, when the corn picker 1 is mounted on the base unit 2, are drivingly connected to a motor of the base unit via a respective output connection on the side of the base unit 1. Each drive connection 18 is connected via one of the shafts 20 oriented transversely to the direction of travel FR to a transmission unit 21 in one of the side walls 14. The width of the corn picker 1 - and thus also the length of the shafts 20 - can vary from one model to another; by making the dimensions of the outlet 12 and the placement of the drive connections 18 uniform for all models, it is ensured that models of the corn picker 1 of different widths can be used on a same base unit 2.FIG. 3 shows one of the gear units 21 concealed in the side walls 14 in a perspective view obliquely from the front. The shaft 20 carries at its outer end a wheel 23 which, via a wheel 22 meshing therewith and a bevel gear 24 connected to the latter in a rotationally fixed manner, drives a bevel gear 25 on a drive shaft 26 of the transmission unit 21.Further wheels 27, 28, 29 are mounted on the drive shaft 26 in a rotationally fixed manner. The wheel 27 meshes with a wheel 30 on an intermediate shaft 31 A driven wheel 32 on a main shaft 33 can mesh directly with the wheel 30. According to a convenient variant, the wheel 32 is interchangeable and the intermediate shaft 31 is lockable in various positions on a circular arc-shaped path having its centre point on the axis of the drive shaft 26, so that the wheel 30 can be engaged with a wheel of different diameter mounted on the main shaft 33 as a replacement for the wheel 32. Thus, different transmission ratios can be realized between the drive shaft 25 and the main shaft 33. The intermediate shaft 31 can also be placed in a position on the circular arc path in which the wheels 30, 32 are disengaged in order to interrupt the torque transmission to the main shaft 33.The main shaft 33 drives chopper units 9 via a pair of bevel gears 34, 35 and a chopper output shaft 36 (see FIG. 4 ) running in the width direction of the corn picker 1.The wheels 28, 29 have different diameters and each mesh with a complementary wheel 37 or 38 on a countershaft 39.The countershaft 39 carries two further wheels 42, 43 which can be selectively coupled rotationally fixedly by a clutch 40, 41 or synchronization device arranged between them. The four different combinations of positions of the clutches 40, 41 or synchronizers correspond to four different transmission ratios between the input shaft 26 and the main shaft 46.The clutches 40, 41 are adjustable along the countershaft 39 with the aid of actuators which are known per se and are not shown in the figures. These can be controlled electrically and / or hydraulically from a driver's cab of the base unit 2. Thus, a driver can change the gear ratio in the course of operation while driving. Alternatively or additionally, a possibility can be provided for actuating the control elements by means of control elements attached to the corn picker 1 itself.The main shaft 46 extends in axial extension of the drive shaft 26; the shafts 26, 33, 39 and 46 lie in a same vertical plane parallel to the direction of travel FR. The distance of the intermediate shaft 31 from this plane may vary depending on the diameter of the wheel 32, but is small in relation to the distance of the shafts 26, 33, 39 and 46 in the vertical direction and therefore does not contribute significantly to the space requirement of the gear unit 21.FIG. 4 shows a model of the corn picker 1 in a schematic plan view. The outlet 12 is shown with the drive connections 18 arranged on both sides thereof and the shafts 20 extending from there to the gear units 21 in both side walls of the corn picker 1, and each gear unit 21 drives the conveying screw 8 from one of its lateral ends via the wheel 23, the picker output shaft 49 via a subunit 50 of the gear unit 21 which comprises the countershaft 39 and the main shaft 46, and the chopper output shaft 36 via a subunit 51 which comprises the intermediate shaft 31 and the main shaft 33.For tolerance compensation between the gear units 21 and the output shafts 36, 39, a compensating clutch 52 such as, for example, an arc clutch can be provided between the bevel gear 35 or 48 and the output shaft 36 or 49 driven above it.The conveying screw 8, the picker output shaft 49 and the chopper output shaft 36 can extend over the entire width of the corn picker 1 or, as indicated for the conveying screw 8, can be divided centrally; by being driven from two sides, a large width of the corn picker 1 of, for example, 16 or 18 row units 15 can be realized.The division of the transmission unit 21 into subunits 50, 51 furthermore has the advantage that, in a corn picker for a customer who does not require a chopper function, the subunit 51 can also be simply omitted together with the chopper units 9 and such a corn picker can be provided cost-effectively.In a smaller width corn picker model, a single gear unit 21 in only one side wall may be sufficient to drive all row units 15. It is also conceivable to omit one of the two subunits 50, 51 on each side wall 14, so that, as shown in FIG. 5, the picking units 17 are driven from one side and the chopping units 9 from the other side. Thus, a more balanced weight distribution is achieved, which facilitates the height control of the corn picker 1 and thus ultimately allows a higher operating speed. Since no other components are required than for the corn picker 1 of FIG. 4, this variant can also be implemented cost-effectively.Reference numerals denote reference numerals1 Corn picker 2 Base unit 3 Tip 4 Guide hood 5 Flank 6 Wall plate 7 Picking roller 8 Conveying screw 9 Chopper unit 10 Deflection roller 11 Deflection roller 12 Outlet 13 Rear wall 14 Side wall 15 Row unit 16 Detection region 17 Picking unit 18 Drive connection 19 Conveying chain 20 Shaft 21 Transmission unit 22 Wheel 23 Wheel 24 Bevel gear 25 Bevel gear 26 Drive shaft 27 Wheel 28 Wheel 29 Wheel 30 Wheel 31 Intermediate shaft 32 Wheel 33 Main shaft 34 Bevel gear 35 Bevel gear 36 Chopper output shaft 37 Wheel 38 Wheel 39 Counter shaft 40 Clutch 41 Clutch 42 Wheel 43 Wheel 44 Wheel 45 Wheel 46 Main shaft 47 Bevel gear 48 Bevel gear 49 Picker output shaft 50 Subunit 51 Subunit 52 Compensating clutchReferences included in the specificationThis list of documents cited by the applicant has been produced in an automated manner and is only included for the better information of the reader. The list is not part of the German patent application or utility model application. The DPMA does not take any adhesion for any faults or omissions.Patent Literature citedEP 2 936 963 B1

[0001]

Claims

A corn picker (1) comprising at least one row unit (15), the row unit (15) comprising a picking unit (17) in which two picking rollers (7) delimit a picking gap and a chopper unit (9) arranged below the picking unit (17) for chopping a straw pulled through the picking gap, and a gear unit (21) comprising a first main shaft (46) for driving the at least one picking unit (17) and a second main shaft (33) for driving the at least one chopper unit (9), characterized in that the gear unit (21) is arranged in a side wall (14) of the corn picker (1) and comprises a drive shaft (26) drivingly connected to the first and second main shafts (46, 33), which extends with the first and the second main shaft (46, 33) in a common vertical plane.Corn picker according to claim 1, characterized in that at least one of the main shafts (46, 33), optionally the first main shaft (46), is connected to the drive shaft (26) via a step-and-step transmission.Corn picker according to Claim 2, characterized in that the step-variable transmission comprises a plurality of pairs of wheels with mutually intermeshing wheels (28, 37; 29, 38; 42, 44; 43, 45), wherein at least one (37, 38, 42, 43) in each case can be switched over from a state coupled rotationally fixedly to the shaft (39) carrying it, and a state rotatable relative to the shaft (39), of the wheels (28, 37; 29, 38; 42, 44; 43, 45) of each pair of wheels.Corn picker according to Claim 3, characterized in that the stepped transmission comprises a countershaft (39), and in that the pairs of wheels each have a first wheel (37, 38, 42, 43) which is supported by the countershaft (39, and second wheels (28, 29, 44, 45) of the pairs of wheels are distributed over the drive shaft (26) and the one main shaft (46).Corn picker according to Claim 3, characterized in that the countershaft (39) runs in the plane of the drive and main shafts (26, 46, 43).Corn picker according to one of Claims 2 to 5, characterized in that a transmission ratio of the stepped transmission can be controlled remotely electrically and / or hydraulically.Corn picker according to one of Claims 3 to 5, characterized in that a clutch (40, 41) is arranged on a shaft (39) between two wheels (37, 38; 42, 43) of different pairs of wheels and can be adjusted between two positions in which it couples in each case one of the adjacent wheels (37, 38; 42, 43) to the shaft (39) in a rotationally fixed manner.Corn picker according to one of the preceding claims, characterized in that at least one other of the main shafts, optionally the second main shaft (33), can be decoupled from the drive shaft (26).Corn picker according to one of the preceding claims, characterized in that at least one other of the main shafts, optionally the second main shaft (33), is coupled to the drive shaft (26) via an intermediate shaft (31), wherein in a wheel pair (30, 32) which couples the intermediate shaft (31) to the other main shaft (33), at least one wheel (32) is replaceable.The corn picker according to any one of the preceding claims, characterized in that the first main shaft (46) is coupled to a plurality of the picking units (17) via a picker output shaft (49) running in the width direction of the corn picker (1), and / or the second main shaft (33) is coupled to a plurality of the chopper units (9) via a chopper output shaft (36) running in the width direction of the corn picker (1).Corn picker according to Claim 10, characterized in that a second gear unit (21) is provided in a second side wall (14) of the corn picker (1), and each gear unit (21) is assigned a picker output shaft (49) and a chopper output shaft (36) in each case.Agricultural machine having a mobile base unit (2) and a corn picker (1) according to one of the preceding claims, in which the drive shaft (26) of the at least one transmission unit (21) is coupled to an output connection of the base unit (2).

Images