Curved support arm for reel assembly

A crop harvesting mechanism having a reel assembly with a reel that is rotatably supported at each end by a respective reel support. A reel carrier arm is provided for each of the reel supports and the supports are movable along the reel carrier arm. A horizontal adjustment actuator moves the reel support along the reel carrier arms over an adjustment range. The reel carrier arms are constructed with an upward or downward oriented curve, inside of the adjustment range over which the reel holding devices can be shifted by the actuator. The reel operates below a cutting bar in its forward position and in a position moved further back that is above and behind the cutting bar so that collisions are avoided.

FIELD OF THE INVENTION

This invention relates to a harvesting mechanism with a reel assembly that is rotatably supported at each end on curved reel carrier arms. Each of the reel carrier arms is pivotably mounted. A horizontal adjustment actuator moves reel supports along the reel carrier arms to provide an enhanced adjustment range.

BACKGROUND OF THE INVENTION

Harvesting mechanisms are used for grain harvesting with self-propelled combines. They usually have a horizontally orientated cutter bar for cutting crop stalks and a transverse conveying auger that feeds the cut crop to the feederhouse of the combine. A pickup reel is located above and in front of the cutter bar to gather the crop to be harvested and to direct crop to the cutter bar and the transverse conveying auger. The pickup reel rotates around a longitudinal axis and is provided with horizontal tine carriers distributed around the longitudinal axis. The tine carriers carry tines that engage the crop stalks.

The reel is usually rotatably mounted on reel supports that are provided on reel carrier arms. The carrier arms are pivotably mounted behind the cutter bar on the frame of the harvesting mechanism and pivot around a horizontal axis transverse to the direction of forward movement. The angle of the reel carrier arm is adjusted by a hydraulic cylinder around the axis, and thus adjusts the height of the reel relative to ground level and the cutter bar. An additional hydraulic cylinder shifts the reel along the reel carrier arm. The position of the reel can thus be varied in the forward and backward direction.

The reel carrier arms are usually straight over their entire length, as shown in the prior art in GB 1 501 639 A, GB 1 574 033 A and WO 03/049532 A. Alternatively, reel carrier arms are provided with bends or angles. Usually the part of the reel carrier arm that cooperates with the reel support is straight, as shown in U.S. Pat. No. 4,800,711, U.S. Pat. No. 6,029,429, DE 195 08 887 C, and DE 195 29 067 A. Therefore, when the reel is shifted along the reel carrier arm, the reel moves in a straight line. The angle or slope of the reel carrier arm relative to the horizontal depends on the pivoting angle of the reel carrier arm around the horizontal axis.

Additionally, some harvesting mechanisms have a two part intake mechanism. A front bottom part carries the cutter bar and is movable in the forward direction. A rear bottom part is fixed solidly to the harvesting mechanism frame. In order to adapt the harvesting mechanism to a crop such as rapeseed, for example, the front bottom part is moved forward. Problems can arise in adjustment of the reel position because collisions between the reel and cutter bar are possible when the front bottom part is adjusted forward. Specifically collisions happen in the area of the cutter bar if the reel is adjusted forward or is lowered too far.

Thus, precautions are taken to prevent such collisions. In U.S. Pat. No. 4,800,711 a mechanical coupling is provided between the cutter bar and the reel carrier arm by a lever mechanism that automatically moves the reel carrier arm vertically as a function of the horizontal position of the cutter bar. A similar mechanical coupling between the reel carrier arm and cutter bar which has a radial cam and a guide roller is described in WO 03/049532 A. To prevent collisions of the reel with the cutter bar, DE 195 08 887 C provides an electronic coupling for positioning the cutting bar via a connection to a sensor that controls an actuator.

The known coupling between the position of the cutting bar and the vertical reel position is disadvantageous in that the operator cannot switch to certain reel positions in a manner that is easily known to him because certain reel positions are blocked mechanically or electronically. Furthermore, the above mechanical and electronic components are relatively expensive and are susceptible to fouling and damage.

Potential collisions between the reel and cutter bar also arises in other types of harvesting mechanisms, especially those with conveyor belts that transport the crop back to a transverse conveying auger which then feeds the crop to the feederhouse of a combine, as described in GB 1 501 639 A, GB 1 574 033 A and GB 1 602 067 A. A sufficiently long horizontal adjustment path of the reel is required to be able to move the reel far enough forward to receive laid crop, and also to be able to move the reel far enough backward for rapeseed harvest to press the crop mat under the transverse conveying auger. The reel should operate below the cutting bar in the forward position but not lie on the conveyor belt in the rear position. This problem could be resolved by a mechanical arrangement, similar to the previously described couplings between the position of the cutter bar and the vertical adjustable reel position, which automatically raises the reel arm when it is moved backward. However, this configuration also has the above-described shortcomings.

SUMMARY OF THE INVENTION

Therefore, the reel carrier arms of the present invention are not straight but are curved and angled upward and/or downward. The reel carrier arms are curved or bent in the adjustment region or assembled from straight parts that enclose an angle to increase the adjustment range.

Thus, during displacement of the reel support by the horizontal adjustment actuator in a manner defined by the curved arm, the reel is displaced not only along the reel carrier arm but also in a direction extending perpendicularly, upwards or downwards, to the direction of adjustment. The reel is moved by the horizontal adjustment actuator on a curved or angular path. The relationship between horizontal and vertical movement can be optimized for the specific circumstances of the harvesting mechanism so that undesirable collisions of the reel with the cutting mechanism parts can be avoided and the movement range of the reel can be optimized.

In particular, a suitable curved shape of the reel carrier arms can enable the reel to operate in its front position below a cutter bar. Additionally, the reel can be shifted further back and located at a relatively small distance above and behind the cutter bar. The vertical adjustment actuator of the reel defines the pivoting angle of the reel carrier arm around the horizontal axis in its lowest position. The curved shape of the carrier arm is particularly advantageous in harvesting mechanisms with conveyor belt assemblies downstream from the cutter bar, which transport the crop backward and feed it to a transverse auger. The curved shape can also be expedient in other harvesting machines, such as in embodiments with a movable cutter bar or in grain harvesting machines with fixed cutter bars that are not equipped with conveyor belts.

DETAILED DESCRIPTION OF THE INVENTION

An agricultural combine10, shown inFIG. 1, is supported on front driven and rear steerable wheels12and14, respectively. An operator cab16is provided from which the combine can be operated by a driver. A grain tank18is located to the rear of the operator cab and can discharge the grain deposited in it out through a discharge auger20. The grain tank18is supported on a frame22. The grain is broken down into its large and small constituents as it passes through a threshing cylinder24, a threshing concave26and a stripper beater28. A further separation of the harvested grain is effected on the shakers30connected thereto, and on a preparation pan32and sieve34. The threshed grain is conveyed into the grain tank18. The large portions of material other than grain are deposited on the ground by the shakers30and the light constituents are also blown onto the ground from the sieve34by a blower36. After the crop lying or standing on the ground has been picked up by a harvesting or cutting mechanism42, it is conveyed through a feederhouse38and a stone catching trough40to the threshing cylinder24. For the description presented below, the directions specified such as front, behind, above and below are relative to the forward direction V of the combine10.

The harvesting mechanism42includes a frame that is assembled of side walls46, a back wall48with a cross beam50on its upper side, and a bottom52. The middle region of the cross beam50is suspended detachably on the feederhouse38by suitable means such as hooks. A cutting bar54with reciprocating knives is located at the front edge of the bottom52. Behind the cutter bar54, relative to the forward direction V, is a ramp56extending over the width of the harvesting mechanism42and inclined slightly toward the rear. Lateral spurs or side cutting mechanisms are arranged on the front side of the side walls46.

Behind the ramp56there are several conveyor belt assemblies58arranged laterally alongside each other with the conveyor direction moving rearward, opposite the forward direction V. A transverse auger60is provided behind the conveyor belts and runs transverse to the forward direction V. The transverse auger60includes an auger tube with spirals welded on the tube and controlled collecting fingers provided in the tube middle section. The conveyor belt assemblies58rise slightly toward the back. Bottom plates62adapted in shape to the conveyor belt assemblies58and the transverse auger60are located at the mechanism underside. A number of conveyor belt assemblies58are arranged laterally side by side and is dependent on the width of the harvesting mechanism42.

Above the cutter bar54and the conveyor belt assemblies58is a driven and rotatable pickup reel44that is adjustable in height and movable in the forward and backward direction. The reel is located on the harvesting mechanism frame, and extends transverse to the forward direction V. On both lateral ends of the frame of the mechanism42, a bracket64is welded on the front of the cross beam50and a reel carrier arm66is pivotably supported around a horizontal axis68running transverse to the forward direction V. The two reel carrier arms66are preferably identical or are mirror-symmetric across the longitudinal midplane.

The reel carrier arms66extend from the axis68initially straight forward and then, at about one-third of its length, bend downward in a first bend angle70. Forward of the bend70in the forward direction V, the reel carrier arms66again extend straight forward and then bend downward, at about two-thirds of the arm length, in a second bend angle72. The reel carrier arms66again extend straight forward of the second bend72. As a result, the reel carrier arms66are somewhat bowed. In order to pivot reel carrier arm66about axis68, a vertical adjustment actuator78, such as a hydraulic cylinder, is positioned between an anchor device76located on the side wall46and a bracket74welded on the reel carrier arm66underneath the first bend70. Means for adjusting the distance between the piston rod of the vertical adjusting actuator78and the bracket74are provided in a known manner.

The reel44is pivotably supported in a reel support80at both ends of curved arms66. The reel support80is in turn movably supported on the reel carrier arm66forward of the bend72. A horizontal adjustment actuator82, such as another hydraulic cylinder, is provided between the reel support80and the bracket74.

The reel support80is shown in an enlarged view inFIG. 2. The reel support80includes vertically running side plates90between which the reel carrier arm66is located. The side plates90are joined above the reel carrier arm66by two bolts92, spaced apart in the forward direction. The bolts each rotatably support a hollow cylindrical roller94, which rolls on the upper side of the curved reel carrier arm66. An additional bolt96extends underneath the reel carrier arm66and carries another rotatable hollow cylindrical roller98that rolls on the underside of the reel carrier arm66. Alternatively, two bolts96with rollers98, one behind the other, could be provided on the underside of the reel carrier arm66to support the reel support80in a more stable manner. Thus the reel support80is movably supported on the reel carrier arm66by the rollers and98. An opening100in the reel support80serves to support the axis of reel44. The piston of the horizontal adjustment actuator82is connected to the support80by a bolt102extending between the side plates. The bolt102can be inserted into any one of four holes104at the bottom of the side plates90. The adjustment range of the reel support80is thus extended for a given adjustment path of the horizontal adjustment actuator82.

The reel44is equipped with six tine carriers86fastened on spiders88. The tine carriers carry tines84arranged alongside each other. The position of the tine carrier and the tines84is varied by conventional control mechanisms during the rotation of the reel44so that the tines84always extend approximately downward and slightly backward from the tine carriers. A control mechanism can involve eccentric levers, as described in the U.S. Pat. No. 4,008,558, or cams running in cam tracks, as disclosed in EP 1 048 199 A.

The cam tracks or eccentric levers can be adjusted around the axis of the reel44to adjust the angular attitude of the tines84as required. The cam tracks or control elements for the eccentric lever do not rotate with the reel44, and are thus fastened on the reel support80, such as at a hole. The reel support80changes its orientation during its movement along the curved reel carrier arm66due to the carrier arm curvature72. Thus, reel support80rotates around a horizontal axis oriented transverse to the forward direction V. Because the attitude of the tines84would thus change, a second support, which moves only between the curves70and72on the curved reel carrier arm66can be coupled with the support80and moves synchronously with it. The second support could be connected with the cam tracks or the control elements for the eccentric lever.

The reel support80and respective lower sections of the reel44are shown in three positions in theFIG. 3. In the frontmost position, in which the reel is designated by44and the reel support by80, the reel44lies sufficiently far forward and the tines84are below the cutting bar54to pick up laid crop. At the rearmost position, in which the reel is designated by44″ and the reel support by80″, the reel44″ lies sufficiently far back to press the crop onto the transverse auger60when harvesting a crop such as rapeseed. In the middle position, the reel44′ is located above the conveyor belt assemblies58.

The movement of the reel support80with the reel44effects a movement on a curved path along the curved reel carrier arm66, which first runs steeply from the front to the back and then runs flatter beyond the bend72. The shape of the reel carrier arm66is adapted to the cutting bar54and the conveyor belt assemblies58.