The knife arm assembly for connecting a sickle drive to the knife of a sickle, has a knife arm including a cavity and an opening at one end that holds a bearing for receiving a knife pin of the sickle, and a shoulder extending at least partially about and defining a second opening at an opposite end of the cavity smaller than the first opening, and a plug disposed in the second end of the cavity adjacent the end of the bearing and enclosing the second opening, the plug being configured to be forceably movable through the cavity toward the first opening and against the bearing for forcing the bearing from the knife arm, providing easy serviceability, protection from dirt, dust, and other contaminants.

A sickle drive incorporated into a generally flat package or enclosure or floor. The drive includes an epicyclic mechanism, including a rotatable input element in an upper region of a cavity of the enclosure, and an eccentric element below the input element rotatable eccentrically thereby. A drive arm is connected to the eccentric element for rotation about, and eccentric rotation with, the eccentric element, and extends to a pivot element which can be the only component extending upwardly from the enclosure or floor, such that the shaft will be pivoted by the eccentric movement of the drive arm. A knife arm connects to the pivot element and a sickle knife assembly which will be reciprocated by the pivoting action. A second epicyclic arrangement can be employed such that opposite forces generated by operation of the drive will be largely canceled.

A header for harvesting agricultural crops includes a cutter bar assembly coupled to a header frame, the cutter bar assembly flexible upwardly and downwardly relative to the header frame between opposite ends thereof for contouring to the field. The cutter bar assembly includes a guard bar extending across a front portion of the header frame between the opposite ends thereof, the guard bar split into at least a first lateral section and a second lateral section operatively coupled at a guard bar joint. A protruding element extending from the first lateral section is received by a receiving element on the second lateral section at the guard bar joint to horizontally align the first and second lateral sections of the guard bar between the opposite ends of the header frame while allowing relative lateral movement therebetween during upward and downward flexing of the cutter bar assembly.

The drive has an input rotatable about an upstanding rotational axis and carries a cam followed by a pivot arm pivotable about an upstanding pivotal axis. A power source is connected in rotatably driving relation to the input. The pivot arm connects to a knife assembly of a sickle. The input, cam and pivot arm are generally flat, and the power source is vertically coextensive therewith for incorporation in or below the floor of a header of a plant cutting machine. Rotation of the input causes offset movement of the cam about the rotational axis, resulting in sideward pivoting of the pivot arm and sickle knife. A second cam drive can oppositely drive a second sickle knife, such that opposite forces generated by operation of the drives will be largely canceled.

A slot driven low profile sickle drive has an input rotatable about an upstanding rotational axis and carries an eccentric captured in a slot in one end of a pivot arm pivotable about an upstanding pivotal axis. A power source is connected in rotatably driving relation to the input. The opposite end of the pivot arm connects to a knife assembly of a sickle. The input, eccentric and pivot arm are generally flat, and the power source is vertically coextensive therewith for incorporation in or below the floor of a header of a plant cutting machine. Rotation of the input causes epicyclical orbiting of the eccentric, resulting in sideward pivoting of the opposite end of the pivot arm and sickle knife. A second drive can oppositely drive a second sickle knife, such that opposite forces generated by operation of the drives will be largely canceled.

The knife head mounts to the sickle to hold a plurality of knife sections thereon while allowing removal of the knife sections individually without major disassembly for ease of in field repair and replacement. A knife pin of the knife head connects to a knife arm driven by the sickle drive mechanism and is removable from above also without major disassembly. The knife pin connection provides a vertical self adjustment capability to accommodate sickle wear and vertical misalignment between the sickle and drive. And the knife arm is streamlined for cut plant material flow thereabout and is also adapted for ease of removal and field repair.

A sickle drive incorporated into a generally flat package or enclosure or floor. The drive includes an epicyclic mechanism, including a rotatable input element in an upper region of a cavity of the enclosure, and an eccentric element below the input element rotatable eccentrically thereby. A drive arm is connected to the eccentric element for rotation about, and eccentric rotation with, the eccentric element, and extends to a pivot element which can be the only component extending upwardly from the enclosure or floor, such that the shaft will be pivoted by the eccentric movement of the drive arm. A knife arm connects to the pivot element and a sickle knife assembly which will be reciprocated by the pivoting action. A second epicyclic arrangement can be employed such that opposite forces generated by operation of the drive will be largely canceled.

A knife drive assembly for use in a harvesting header may be mounted near the center line of the cutter bar of the header. Mechanical power from the power unit behind the header (typically the combine power output shaft) may be translated for application to two knife assembly sections in the cutter bar at the front of the cutter table. Movement of the two knife assembly sections with this apparatus can be fully synchronized and 180 degrees out of phase, to maximize cutting effectiveness and minimize vibration of the header. The unitary drive assembly may allow for rapid repair and manufacture, and the size and weight of the knife drive assembly may represent a significant weight and balance advantage over the prior art.

A working machine may include: a first blade; a second blade overlapping with the first blade in an up-down direction; and a holding unit configured to hold the first blade and the second blade overlapping each other in the up-down direction. The first blade may be configured to reciprocate in a direction perpendicular to the up-down direction with respect to the second blade. The first blade may include a first elongated hole having a longitudinal direction along the reciprocating direction. The second blade may include a second elongated hole having a longitudinal direction along the reciprocating direction. The holding unit may include: a holding part inserted in the first elongated hole of the first blade and the second elongated hole of the second blade; and an outer sleeve having a cylindrical shape and supported by the holding part such that the outer sleeve is rotatable around the holding part.