Corn picker and agricultural machine equipped with it

Abstract

A corn picker (1) comprises several row units (15) distributed between a first side wall (14) and an opposing second side wall (14) of the corn picker (1), each row unit (15) comprising a picking unit (17) in which two picking rollers (7) define a picking gap, and a chopping unit (9) arranged below the picking unit (17) to chop a stalk drawn through the picking gap. Among the picking units (17), those adjacent to the first side wall (14) are coupled to a common first picker drive shaft (49), and those adjacent to the second side wall (14) are coupled to a common second picker drive shaft (49).Among the chopping units (9), those adjacent to the first side wall (14) are coupled to a common first chopping output shaft (36), and those adjacent to the second side wall (14) are coupled to a common second chopping output shaft (36).

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. In addition, the requirements for the torsional rigidity of the output shafts become greater and greater the greater the working width of the corn picker is to be. If output shafts of different thicknesses are used depending on the working width, this considerably complicates the manufacturing logistics. If waves of equal strength are used regardless of the working width, so equal, resulting in the weight of the corn picker increasing more than linearly with the working width.An object of the invention is to specify a structure for a corn picker with which different models with different working widths, in particular those with large working widths, can be realized in a simple and cost-effective manner.According to one aspect of the invention, the object is achieved in that, in a corn picker having a plurality of row units distributed between a first side wall and an opposite second side wall of the corn picker, wherein the row unit comprises a picking unit in which two picking rollers delimit a picking gap and a chopping unit which is arranged below the picking unit in order to chop a straw which has been pulled through the picking gap, among the picking units those which are adjacent to the first side wall are coupled to a common first picker output shaft and those which are adjacent to the second side wall are coupled to a common second picker output shaft, and among the chopping units those which are adjacent to the first side wall, a common first chopper output shaft and ones adjacent the second side wall are coupled to a common second chopper output shaft. By thus driving picker and chopper output shafts from two sides of the corn picker, the torque to be transmitted from each individual output shaft is reduced; due to correspondingly lower requirements on the torsional stiffness of the output shafts and of the structures supporting them, the weight of the corn picker can be kept low. Corn picker models of reduced working width are simple and cost effective to implement by simply eliminating components rather than varying their shape.Mutually facing ends of the first and second picker output shaft and / or mutually facing ends of the first and second chopper output shaft are preferably spaced apart from one another by an intermediate space. Thus, in a model with a reduced working width, not only can a transmission unit not required for driving the output shafts from the side wall be omitted, but also one of the picker and / or chopper output shafts at a time.Preferably, the first picker output shaft and the first chopper output shaft form an output side of a first gear unit, and the second picker output shaft and the second chopper output shaft form an output side of a second gear unit, which is different from the first gear unit.The gear units can each be accommodated in a space-saving manner in the first or the second side wall.Each gear unit may comprise a drive shaft and two main shafts, a first of which is drivingly connected to one of the picker output shafts and the second of which is drivingly connected to one of the chopper output shafts. Because the drive shaft and the two main shafts extend in a common, in particular vertical, plane, space-saving accommodation of the gear units in the side walls of the corn picker is possible.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 that the countershaft runs in the plane of the drive and main shafts and / or the drive shaft and the one main shaft run coaxially.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 invention further relates to an agricultural machine having a mobile base unit and a corn picker as described above, in which the base unit comprises a first output connection to which the first picker output shaft and the first chopper output shaft are coupled, and a second output connection to which the second picker output shaft and the second chopper output shaft are coupled, and in which optionally speeds of the first and the second output connection can be set differently.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 according to the invention; and FIG. 5 shows a schematic plan view of a second model of the corn picker that can be derived from the first model but is not according to the invention.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 18 on the side of the base unit 1. Each drive connection 18 is connected via a shaft 20 oriented transversely to the direction of travel FR to a gear 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, such as an arc clutch, can be provided between the bevel gear 35 or 48 and the output shaft 36 or 49 driven above it.The auger 8, the picker output shaft 49 and the chopper output shaft 36 may extend over the entire width of the corn picker 1; by being driven from two sides, a large width of the corn picker 1 of e.g. 16 or 18 row units 15 can be realized. Alternatively, as shown in FIG. 4, they may each be divided by a clearance 52 into a left auger 8, picker output shaft 49 and chopper output shaft 36 driven by the left side wall gear unit 21 and a right auger 8, picker output shaft 49 and chopper output shaft 36 driven by the right side wall gear unit 21; also so, a wide width of the corn picker 1 can be realized, and besides, the left and right output shafts 49, 36 can be driven at different rotational speeds by the base unit 2 because they are each driven via a dedicated drive port 18.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 order to create a corn picker pattern of smaller width, it may be sufficient to insert only the left or only the right picker output shaft 49 and chopper output shaft 36 with the associated picking and chopper units 17, 9 and a single drive unit 21 into a frame in which the distance between the side walls 14 is reduced by the length of the omitted output shafts.Typically, the right and left output shafts 49 and 36 are each of equal length in order to minimize the number of different components required for assembling the corn picker of FIG. 4, and the working width of the model according to FIG. 5 derived from the corn picker of FIG. 4 is half the working width of the corn picker of FIG. 4. however, it is also conceivable to use output shafts 49, 36 in each case on the right and left in FIG. 4 in different lengths and with different numbers of driven picking and chopping units, such that two models of different width according to FIG. 5 can be derived from the corn picker of FIG. 4, depending on whether the longer or the shorter output shafts are retained.Another embodiment of a corn picker of reduced width is shown in Figure 5. Instead of completely omitting the transmission unit 21 in one of the side walls 14, the subunit 51 is omitted in the transmission unit of the left side wall and the subunit 50 and the wheels 22, 23 for driving the conveying screw 8 are omitted in the right side wall 14. The wheels 22, 23 remaining on the left side and the subunit 50 drive the conveying screw 8 and the picker drive shaft 48; the subunit 51 on the right side drives the chopper drive shaft 36 so that the picking units 17 are each driven from one side and the chopper units 9 are each driven 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 Intermediate spaceReferences 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 a plurality of row units (15) distributed between a first side wall (14) and an opposite second side wall (14) of the corn picker (1), each row unit (15) comprising a picking unit (17) in which two picking rollers (7) delimit a picking gap and a chopping unit (9) arranged below the picking unit (17) for chopping a straw pulled through the picking gap, characterised in that among the picking units (17) those adjacent to the first side wall (14) are coupled to a common first picker output shaft (49) and those adjacent to the second side wall (14) are coupled to a common second picker output shaft (49), and that among the chopper units (9), those adjacent to the first side wall (14) are coupled to a common first chopper output shaft (36) and those adjacent to the second side wall (14) are coupled to a common second chopper output shaft (36).Corn picker according to claim 1, characterised in that mutually facing ends of the first and second picker output shaft (49) and / or mutually facing ends of the first and second chopper output shaft (36) are spaced apart from one another by an intermediate space (52).Corn picker according to claim 1 or 2, characterized in that the first picker output shaft (49) and the first chopper output shaft (36) form an output side of a first gear unit (21), and the second picker output shaft (49) and the second chopper output shaft (36) form an output side of a second gear unit (21) different from the first gear unit (21).Corn picker according to claim 3, characterized in that the first gear unit (21) is accommodated in the first side wall (14) and the second gear unit (21) is accommodated in the second side wall (14).Corn picker according to claim 3 or 4, characterised in that each gear unit (21) comprises a drive shaft (26) and two main shafts (33, 46), a first (46) of which is drivingly connected to one of the picker drive shafts (49) and the second (33) is drivingly connected to one of the chopper drive shafts (36), and in that the drive shaft (26) and the two main shafts (33, 46) run in a common, in particular vertical, plane.Corn picker according to claim 5, 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 6, 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 in a rotationally fixed manner to the shaft (39) carrying it, and from 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 7, 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 8, characterized in that the countershaft (39) runs in the plane of the drive and main shafts (26, 46, 43) and / or the drive shaft (26) and the one main shaft (46) run coaxially.Corn picker according to one of Claims 6 to 9, 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 7 to 9, 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 Claims 5 to 11, 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 claims 5 to 12, characterised 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.Agricultural machine having a mobile base unit (2) and a corn picker (1) according to one of the preceding claims, in which the base unit (2) comprises a first output connection to which the first picker output shaft and the first chopper output shaft are coupled, and a second output connection to which the second picker output shaft and the second chopper output shaft are coupled, and in which optionally speeds of the first and the second output connection can be set differently.

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