Hydraulic sickle knife drive on a combine header

A sickle knife drive for an agricultural vehicle generally includes a first pump, a first motor, a second motor and a drive manifold having a plurality of connections used for connecting to other devices of the sickle knife drive and/or to devices outside of the sickle knife drive. Operation of the first pump in a forward direction causes the first motor to drive a sickle knife gearbox to cut a crop. During the forward direction, the second motor provides cooling to the fluid circuit. When the first pump direction is reversed, the agricultural vehicle supplements a fluid flow to the fluid circuit to clear any jammed crop from the sickle knives.

FIELD OF THE INVENTION

The present invention relates to agricultural harvesters, and, more specifically to the cutter bar of the header of agricultural harvesters.

BACKGROUND OF THE INVENTION

An agricultural vehicle known as a “combine” is historically termed such because it combines multiple harvesting functions with a single harvesting unit, such as picking, threshing, separating, and cleaning. A combine generally includes a header, a feeder housing, a threshing rotor, and various other systems for the separation, cleaning, and temporary storage of the crop material. The header removes the crop material from a field and transports the crop material to the feeder housing.

A typical header for an agricultural vehicle includes one or more cutters, e.g., cutter bars with reciprocating knives, which cut the crop material that is harvested from the field. Generally, the cutter bars are driven in a linearly reciprocal manner by a knife drive, such as a “wobble box” or epicyclic gear drive. The knife drive is usually powered by a mechanical drivetrain that extends from the combine. Thereby, the knife drive converts rotary motion from the mechanical drivetrain into a linear motion that drives the cutter bar.

The cutter bar of the header typically includes a reciprocating blade moving atop a bar on which there are mounted fingers with stationary guard plates. The reciprocating blade operates in a channel on the bar and has very sharp sickle sections (triangular blades). The reciprocating blade is driven back and forth along the channel. The plant matter, is cut between the sharp edges of the sickle sections and the finger guard plates.

A typical header includes one or more cutters, e.g., cutter bars with reciprocating knives, which cut the crop material that is harvested from the field. Once the crop material is cut, a conveyor system, which is positioned rearwardly of the cutter(s), catches the crop material and transports it to the feeder housing. The header may also include a rotating reel with tines or the like to sweep the crop material towards the cutter(s). Modern headers generally have cutters and attachments which are specifically optimized to harvest a particular kind of crop material.

A typical header generally includes a frame, a pair of end dividers at the lateral ends of the frame, a cutter to remove crop material from the field, and a conveyor to transport the cut crop material to the feeder housing for further downstream processing in the combine. Generally, these features of a header are specifically optimized to harvest a particular kind of crop material. For instance, the header may be in the form of a draper header which has a cutter bar, a draper belt, and a rotating reel with tines or the like in order to harvest a bushy or fluffy crop material, such as soy beans or canola. Alternatively, the header may be in the form of a corn header which includes an auger and row units with snouts, gathering chains, and stalk rolls for harvesting corn.

Draper headers may further include a reel drive assembly for rotating the reel. A typical reel drive assembly can include a hydraulic motor connected to the reel and various hydraulic fluid lines which fluidly couple the hydraulic motor to the onboard hydraulic system of the combine. The hydraulic motor may selectively rotate the reel at a desired rotational speed for accommodating a crop condition and/or ground speed of the combine. However, the operating parameters of the hydraulic motor may prevent the reel drive assembly from adequately accommodating some crop conditions.

SUMMARY OF THE INVENTION

In one exemplary embodiment formed in accordance with the present disclosure, there is provided a sickle knife drive for a plurality of sickle knives on an agricultural combine header of a combine. The sickle knife drive includes a drive manifold, a first pump, a first motor and a second pump. The drive manifold includes a plurality of connections, e.g. a first pump connection, a first motor connection, a second motor connection, a combine connection and a manifold case drain connection. The combine connection and the manifold case drain are configured for connecting to the combine. The first pump is in fluid connection with the first pump connection and is configured to mechanically couple to a power transmission device. The first pump includes a first pump case drain that is configured to connect to the combine. The first pump creates a system state, e.g. a forward state, a reverse state and a neutral state. The drive manifold has a forward position during the forward state, a reverse position during the reverse state and either the forward position or the reverse position during the neutral state. The first motor is in fluid connection with the first motor connection and is configured to drive a sickle knife gear box. The first motor includes a first motor case drain that is connected to the combine. The second motor is in fluid connection with the second motor connection.

In another exemplary embodiment formed in accordance with the present disclosure, there is provided a method of adding a sickle knife drive to sickle knives on an agricultural combine header.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to the drawings, and more particularly toFIG. 1, there is shown an exemplary embodiment of an agricultural vehicle100in the form of a combine. However, the agricultural vehicle100may be in the form of any desired agricultural vehicle100, such as a windrower. The agricultural vehicle100generally includes a chassis102, ground engaging wheels104, a feeder housing106, and a prime mover108. The agricultural vehicle100may also include a header110, a separating system120, a cleaning system130, a discharge system140, an onboard grain tank150, and an unloading auger160. Although the agricultural vehicle100is shown as including wheels104, in an alternative exemplary embodiment the agricultural vehicle100may include tracks, such as full tracks or half-tracks.

The header110is removably attached to the feeder housing106. The header110generally includes a frame112, a cutter bar114having a plurality of sickle knives115used to sever the crop from a field, a rotatable reel116rotatably mounted to the frame112which feeds the cut crop into the header110, and an auger118with flighting that feeds the severed crop inwardly from each lateral end of the frame112toward feeder housing106. The reel116may be in the form of any desired reel. The header110further includes the sickle knife drive170configured to drive the sickle knives115.

Referring now toFIG. 2, there is shown a top view of the agricultural vehicle100shown inFIG. 1with a cutaway of the rotatable reel116showing the cutter bar114with the plurality of sickle knives115.

Shown inFIG. 3is a block diagram of a sickle knife drive170represented inside of the dashed lines. The sickle knife drive170generally includes a drive manifold172having a plurality of connections used for connecting to other devices of the sickle knife drive170and/or to devices outside of the sickle knife drive170. The plurality of connections may include a first pump connection174, a first motor connection176, a second motor connection178and a combine connection180. The drive manifold172is configured to fluidly connect with the combine connection180, e.g. hydraulically, to an agricultural vehicle100. The drive manifold172further includes a manifold case drain188connecting to the agricultural vehicle100. The connection between the manifold case drain188and the agricultural vehicle100may be of any type of connection suitable for a hydraulic link, e.g. permanent or quick connect. The drive manifold172may be configured with various pilot operated valves and controls typical for use in hydraulic systems, e.g. check valves, directional valves, needle valves or flow controls, in order to direct a flow. The drive manifold172may be configured to provide a forward flow unless the drive manifold172is subjected to a reverse flow thereby causing the system to develop pressure and shift the various pilot operated valves to the reverse flow. It is to be understood that the drive manifold172may instead be configured to provide a reverse flow unless the drive manifold172is subjected to a forward flow thereby causing the system to develop pressure and shift the various pilot operated valves to the forward flow. The sickle knife drive170further includes a first pump182, a first motor184and a second motor186.

The first pump182may be of any type of pump suitable for pumping a fluid, e.g. a single gear pump, and is fluidly connected to the drive manifold172at the first pump connection174. The fluid connection between the first pump182and the first pump connection174may be of any connection suitable for hydraulic fluid, e.g. flexible hose or hard lines, where pressures may exceed 3000 psi. The first pump is configured to connect, e.g. electrically, mechanically or fluidly, to a power transmission device192, e.g. generator, power take off or pump, where the power transmission device192may turn the first pump182in a forward direction, a reverse direction or not at all. A controller (not shown) located on the agricultural vehicle100may be used to select the forward or reverse direction or to stop the power transmission device192thus providing no rotation to the first pump182. The sickle knife drive170is in a forward state when the power transmission device182is turning the first pump182in the forward direction, a reverse state when the power transmission device182is turning the first pump182in the reverse direction and a neutral state when the power transmission device182is not turning the first pump182in either direction. The first pump182may also include a first pump case drain194connected to the agricultural vehicle100. The connection between the first pump182and the agricultural vehicle100may be of any type of connection suitable for a hydraulic link, e.g. permanent or quick connect.

The first motor184may be of any type of motor suitable for connecting to and driving a sickle knife gear box196. The first motor184is fluidly connected to the drive manifold172at the first motor connection176. The fluid connection between the first motor184and the first motor connection176may be of any connection suitable for hydraulic fluid, e.g. flexible hose or hard lines, where pressures may exceed 3000 psi. The first motor184includes a first case motor drain198connected to the agricultural vehicle100. The connection between the first motor184and the agricultural vehicle100may be of any type of connection suitable for a hydraulic link, e.g. permanent or quick connect. The connection between the first motor184and the sickle knife gearbox196may be of any type suitable for driving a gear box, e.g. direct linkage, clutch or other gear box.

The second motor186may be of any type of motor suitable for connecting to and driving the rotatable reel116. The second motor186is fluidly connected to the drive manifold172at the second motor connection178. The fluid connection between the second motor186and the second motor connection178may be of any connection suitable for hydraulic fluid, e.g. flexible hose or hard lines, at low pressures.

The sickle knife drive170may be in one of three system states as dictated by the rotation direction of the first pump182. The system states are a forward state, a reverse state and a neutral state. The forward state is defined as the state the system may be in during the harvesting of a crop, the reverse state is defined as the state the system may be in during clearing of crop jammed in the sickle knives115and the neutral state is defined the state the system may be in when not in the forward or reverse state. The sickle knife drive170is in a forward state when the power transmission device192is turning the first pump182in the forward direction, a reverse state when the power transmission device192is turning the first pump182in the reverse direction and a neutral state when the power transmission device192is not turning the first pump182in either direction. A controller (not shown) located on the agricultural vehicle100may be used to select the forward or reverse direction or to stop the power transmission device192thus providing no rotation to the first pump182.

During the forward state of the sickle knife drive170, the drive manifold172is in a forward flow position thereby allowing the first pump182to provide approximately 15 gallons per minute (gpm) of a forward flow to the first motor184. The forward flow to the first motor184causes the first motor184to rotate in a forward direction. This forward rotation of the first motor184causes the sickle knives115to operate in a harvesting mode, i.e. cutting a crop. During the forward state of the sickle knife drive170, the second motor186provides an additional forward flow of about 10-20% of the first pump182. The additional forward flow from the second motor186is used to supplement and to cool the fluid in the circuit between the first pump182and the first motor184. The second motor196may advantageously provide the additional forward flow at an output pressure of the second motor196.

During the reverse state of the sickle knife drive170, the drive manifold172is shifted to the reverse flow position by the first pump182operating in a reverse direction and creating a reverse flow. In other words, the default position of the drive manifold172is in the forward flow position. However, it is to be understood that the system may have a default position of a reverse flow position where a forward flow from the first pump182would cause the drive manifold172to shift from the reverse flow position to the forward flow position. The first pump172, in the reverse flow provides 1.0-1.9 gpm to the first motor184. The reverse flow to the first motor184causes the first motor184to rotate in a reverse direction. This reverse rotation of the first motor184causes the sickle knives115to operate in a cleaning mode, i.e. clearing a jammed crop. During the reverse state of the sickle knife drive, the second motor186does not supplement the reverse flow. The drive manifold172diverts a low flow from the agricultural vehicle100supplied to the second motor186during a forward flow position to the first motor184during a reverse flow position. The low flow of the agricultural vehicle to the second motor186is 5-10 gpm and to the first motor184is approximately 1.5 gpm. The additional low flow from the agricultural vehicle100to the first motor184advantageously supplements the flow from the first pump182to the first motor184thereby providing a consistent operation from of sickle knives115, i.e. the flow rate to the first motor184is consistent. It is to be understood that the amount of flow that is required from the agricultural vehicle100may be adjusted dependent upon the rotational speed of the power transmission device192. In other words, the amount of flow required to be supplemented may be low on an agricultural vehicle100having a power transmission device192with a high rotational speed; whereas, the amount of flow required to be supplemented may be high on an agricultural vehicle100having a power transmission device192with a low rotational speed.

During the neutral state of the sickle knife drive170, the drive manifold172is not in a forward flow or reverse flow position. The drive manifold172may be configured to have a default forward flow position or a reverse flow position when the system pressure is 0 psi. Therefore, as the first pump182is not in the forward or reverse direction, the flow provided through the sickle knife drive170is 0 gpm.

The sickle knife drive170may be added to any agricultural vehicle100having a mechanical or hydraulic system utilized for driving the sickle knives115. In a configuration using a mechanical drive, the mechanical drive unit (not shown) used to drive the sickle knives115may be replaced with a sickle knife drive170. In a configuration with a hydraulic drive, the addition of fluid lines from the second motor186to the drive manifold172are required and case drains must be added between agricultural vehicle100and the first pump182, the first motor184and the drive manifold172. A software upgrade to the controller (not shown) may be required for both configurations.

Referring now toFIG. 4, there is shown a block diagram of a sickle knife drive170in a harvest mode with the drive manifold172in the forward flow position.

Referring now toFIG. 5, there is shown a block diagram of a sickle knife drive170in a cleaning mode with the drive manifold172in the reverse flow position.

Referring now toFIG. 6, there is shown a block diagram of a sickle knife drive170in a neutral mode with the drive manifold172in the forward flow position.

Referring now toFIG. 7, there is shown a method700of adding a sickle knife drive170to sickle knives115on an agricultural combine header. The method700generally includes the steps of providing a combine including an agricultural combine header with the sickle knives coupling with a sickle knife gear box that is driven by a mechanical drive. The combine further including a manifold, a low pressure tank, a software device configured to control the mechanical drive and a power transmission device (step702). Decoupling the mechanical drive from the sickle knives (step704). Replacing the mechanical drive with a drive manifold, a first pump and a first motor. The drive manifold includes a plurality of connections, e.g. a first pump connection, a first motor connection, a second motor connection, a combine connection and a manifold case drain connection. The combine connection connects to the manifold and the manifold case drain connects to the low pressure tank. The first pump is in fluid connection with the first pump connection and is mechanically coupled to the power transmission device. The first pump includes a first pump case drain that connects to the low pressure tank. The first pump creates a system state, e.g. a forward state, a reverse state and a neutral where the drive manifold has a forward position during the forward state, a reverse position during the reverse state and either the forward position or the reverse position during the neutral state. The first motor is in fluid connection with the first motor connection and connects to the sickle knife gear box. The first motor includes a first motor case drain connecting to the low pressure tank (step706). Arranging a second motor provided with the combine to be in fluid connection to the second motor connection (step708).