Patent Description:
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. An example of a typical header is disclosed in Canadian patent application <CIT>, wherein a header is disclosed that is hydraulically driven by a pair of pumps on a tractor and a series of motors on the header. A first circuit control includes variable rate valves controlling the rate of supply of fluid from the unidirectional pumps to the motors to vary rate of the knife, conditioner, reel and converging systems in a forward harvesting direction. A second circuit controls reverse rotation of at least some of the elements for releasing a blockage by taking the fluid from one of the pumps and passing it through the separate second circuit to the required motors in series. The drive of the motors in reverse direction in series ensures that they are driven at common speed without need for individual speed control.

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.

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.

Referring now to the drawings, and more particularly to <FIG>, there is shown an exemplary embodiment of an agricultural vehicle <NUM> in the form of a combine. However, the agricultural vehicle <NUM> may be in the form of any desired agricultural vehicle <NUM>, such as a windrower. The agricultural vehicle <NUM> generally includes a chassis <NUM>, ground engaging wheels <NUM>, a feeder housing <NUM>, and a prime mover <NUM>. The agricultural vehicle <NUM> may also include a header <NUM>, a separating system <NUM>, a cleaning system <NUM>, a discharge system <NUM>, an onboard grain tank <NUM>, and an unloading auger <NUM>. Although the agricultural vehicle <NUM> is shown as including wheels <NUM>, in an alternative exemplary embodiment the agricultural vehicle <NUM> may include tracks, such as full tracks or half-tracks.

The header <NUM> is removably attached to the feeder housing <NUM>. The header <NUM> generally includes a frame <NUM>, a cutter bar <NUM> having a plurality of sickle knives <NUM> used to sever the crop from a field, a rotatable reel <NUM> rotatably mounted to the frame <NUM> which feeds the cut crop into the header <NUM>, and an auger <NUM> with flighting that feeds the severed crop inwardly from each lateral end of the frame <NUM> toward feeder housing <NUM>. The reel <NUM> may be in the form of any desired reel. The header <NUM> further includes the sickle knife drive <NUM> configured to drive the sickle knives <NUM>.

Referring now to <FIG>, there is shown a top view of the agricultural vehicle <NUM> shown in <FIG> with a cutaway of the rotatable reel <NUM> showing the cutter bar <NUM> with the plurality of sickle knives <NUM>.

Shown in <FIG> is a block diagram of a sickle knife drive <NUM> represented inside of the dashed lines. The sickle knife drive <NUM> generally includes a drive manifold <NUM> having a plurality of connections used for connecting to other devices of the sickle knife drive <NUM> and/or to devices outside of the sickle knife drive <NUM>. The plurality of connections may include a first pump connection <NUM>, a first motor connection <NUM>, a second motor connection <NUM> and a combine connection <NUM>. The drive manifold <NUM> is configured to fluidly connect with the combine connection <NUM>, e.g. hydraulically, to an agricultural vehicle <NUM>. The drive manifold <NUM> further includes a manifold case drain <NUM> connecting to the agricultural vehicle <NUM>. The connection between the manifold case drain <NUM> and the agricultural vehicle <NUM> may be of any type of connection suitable for a hydraulic link, e.g. permanent or quick connect. The drive manifold <NUM> may 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 manifold <NUM> may be configured to provide a forward flow unless the drive manifold <NUM> is 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 manifold <NUM> may instead be configured to provide a reverse flow unless the drive manifold <NUM> is 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 drive <NUM> further includes a first pump <NUM>, a first motor <NUM> and a second motor <NUM>.

The first pump <NUM> may be of any type of pump suitable for pumping a fluid, e.g. a single gear pump, and is fluidly connected to the drive manifold <NUM> at the first pump connection <NUM>. The fluid connection between the first pump <NUM> and the first pump connection <NUM> may be of any connection suitable for hydraulic fluid, e.g. flexible hose or hard lines, where pressures may exceed <NUM> psi. The first pump is configured to connect, e.g. electrically, mechanically or fluidly, to a power transmission device <NUM>, e.g. generator, power take off or pump, where the power transmission device <NUM> may turn the first pump <NUM> in a forward direction, a reverse direction or not at all. A controller (not shown) located on the agricultural vehicle <NUM> may be used to select the forward or reverse direction or to stop the power transmission device <NUM> thus providing no rotation to the first pump <NUM>. The sickle knife drive <NUM> is in a forward state when the power transmission device <NUM> is turning the first pump <NUM> in the forward direction, a reverse state when the power transmission device <NUM> is turning the first pump <NUM> in the reverse direction and a neutral state when the power transmission device <NUM> is not turning the first pump <NUM> in either direction. The first pump <NUM> may also include a first pump case drain <NUM> connected to the agricultural vehicle <NUM>. The connection between the first pump <NUM> and the agricultural vehicle <NUM> may be of any type of connection suitable for a hydraulic link, e.g. permanent or quick connect.

The first motor <NUM> may be of any type of motor suitable for connecting to and driving a sickle knife gear box <NUM>. The first motor <NUM> is fluidly connected to the drive manifold <NUM> at the first motor connection <NUM>. The fluid connection between the first motor <NUM> and the first motor connection <NUM> may be of any connection suitable for hydraulic fluid, e.g. flexible hose or hard lines, where pressures may exceed <NUM> psi. The first motor <NUM> includes a first motor case drain <NUM> connected to the agricultural vehicle <NUM>. The connection between the first motor <NUM> and the agricultural vehicle <NUM> may be of any type of connection suitable for a hydraulic link, e.g. permanent or quick connect. The connection between the first motor <NUM> and the sickle knife gearbox <NUM> may be of any type suitable for driving a gear box, e.g. direct linkage, clutch or other gear box.

The second motor <NUM> may be of any type of motor suitable for connecting to and driving the rotatable reel <NUM>. The second motor <NUM> is fluidly connected to the drive manifold <NUM> at the second motor connection <NUM>. The fluid connection between the second motor <NUM> and the second motor connection <NUM> may be of any connection suitable for hydraulic fluid, e.g. flexible hose or hard lines, at low pressures.

The sickle knife drive <NUM> may be in one of three system states as dictated by the rotation direction of the first pump <NUM>. 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 knives <NUM> and the neutral state is defined the state the system may be in when not in the forward or reverse state. The sickle knife drive <NUM> is in a forward state when the power transmission device <NUM> is turning the first pump <NUM> in the forward direction, a reverse state when the power transmission device <NUM> is turning the first pump <NUM> in the reverse direction and a neutral state when the power transmission device <NUM> is not turning the first pump <NUM> in either direction. A controller (not shown) located on the agricultural vehicle <NUM> may be used to select the forward or reverse direction or to stop the power transmission device <NUM> thus providing no rotation to the first pump <NUM>.

During the forward state of the sickle knife drive <NUM>, the drive manifold <NUM> is in a forward flow position thereby allowing the first pump <NUM> to provide approximately <NUM> gallons per minute (gpm) of a forward flow to the first motor <NUM>. The forward flow to the first motor <NUM> causes the first motor <NUM> to rotate in a forward direction. This forward rotation of the first motor <NUM> causes the sickle knives <NUM> to operate in a harvesting mode, i.e. cutting a crop. During the forward state of the sickle knife drive <NUM>, the second motor <NUM> provides an additional forward flow of about <NUM>-<NUM>% of the first pump <NUM>. The additional forward flow from the second motor <NUM> is used to supplement and to cool the fluid in the circuit between the first pump <NUM> and the first motor <NUM>. The second motor <NUM> may advantageously provide the additional forward flow at an output pressure of the second motor <NUM>.

During the reverse state of the sickle knife drive <NUM>, the drive manifold <NUM> is shifted to the reverse flow position by the first pump <NUM> operating in a reverse direction and creating a reverse flow. In other words, the default position of the drive manifold <NUM> is 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 pump <NUM> would cause the drive manifold <NUM> to shift from the reverse flow position to the forward flow position. The first pump <NUM>, in the reverse flow provides <NUM>-<NUM> gpm to the first motor <NUM>. The reverse flow to the first motor <NUM> causes the first motor <NUM> to rotate in a reverse direction. This reverse rotation of the first motor <NUM> causes the sickle knives <NUM> to operate in a cleaning mode, i.e. clearing a jammed crop. During the reverse state of the sickle knife drive, the second motor <NUM> does not supplement the reverse flow. The drive manifold <NUM> diverts a low flow from the agricultural vehicle <NUM> supplied to the second motor <NUM> during a forward flow position to the first motor <NUM> during a reverse flow position. The low flow of the agricultural vehicle to the second motor <NUM> is <NUM>-<NUM> gpm and to the first motor <NUM> is approximately <NUM> gpm. The additional low flow from the agricultural vehicle <NUM> to the first motor <NUM> advantageously supplements the flow from the first pump <NUM> to the first motor <NUM> thereby providing a consistent operation from of sickle knives <NUM>, i.e. the flow rate to the first motor <NUM> is consistent. It is to be understood that the amount of flow that is required from the agricultural vehicle <NUM> may be adjusted dependent upon the rotational speed of the power transmission device <NUM>. In other words, the amount of flow required to be supplemented may be low on an agricultural vehicle <NUM> having a power transmission device <NUM> with a high rotational speed; whereas, the amount of flow required to be supplemented may be high on an agricultural vehicle <NUM> having a power transmission device <NUM> with a low rotational speed.

During the neutral state of the sickle knife drive <NUM>, the drive manifold <NUM> is not in a forward flow or reverse flow position. The drive manifold <NUM> may be configured to have a default forward flow position or a reverse flow position when the system pressure is <NUM> psi. Therefore, as the first pump <NUM> is not in the forward or reverse direction, the flow provided through the sickle knife drive <NUM> is <NUM> gpm.

The sickle knife drive <NUM> may be added to any agricultural vehicle <NUM> having a mechanical or hydraulic system utilized for driving the sickle knives <NUM>. In a configuration using a mechanical drive, the mechanical drive unit (not shown) used to drive the sickle knives <NUM> may be replaced with a sickle knife drive <NUM>. In a configuration with a hydraulic drive, the addition of fluid lines from the second motor <NUM> to the drive manifold <NUM> are required and case drains must be added between agricultural vehicle <NUM> and the first pump <NUM>, the first motor <NUM> and the drive manifold <NUM>. A software upgrade to the controller (not shown) may be required for both configurations.

Referring now to <FIG>, there is shown a block diagram of a sickle knife drive <NUM> in a harvest mode with the drive manifold <NUM> in the forward flow position.

Referring now to <FIG>, there is shown a block diagram of a sickle knife drive <NUM> in a cleaning mode with the drive manifold <NUM> in the reverse flow position.

Referring now to <FIG>, there is shown a block diagram of a sickle knife drive <NUM> in a neutral mode with the drive manifold <NUM> in the forward flow position.

Claim 1:
A sickle knife drive (<NUM>) for a cutter bar (<NUM>) on a header (<NUM>) of an agricultural combine (<NUM>), the sickle knife drive (<NUM>) comprising:
a hydraulic drive manifold (<NUM>) having a plurality of connections comprising a first pump connection (<NUM>), a first motor connection (<NUM>), a second motor connection (<NUM>), a combine connection (<NUM>) and a manifold case drain (<NUM>), the combine connection (<NUM>) being configured for connecting to the combine (<NUM>), the manifold case drain being configured to connect to the combine (<NUM>);
a first pump (<NUM>) in fluid connection with the first pump connection (<NUM>) and configured to mechanically couple to a power transmission device (<NUM>), the first pump (<NUM>) comprising a first pump case drain (<NUM>) being configured to connect to the combine (<NUM>), the first pump (<NUM>) creating at least one system state comprising at least one of a forward state, a reverse state and a neutral state, the hydraulic drive manifold (<NUM>) comprising 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;
a first motor (<NUM>) in fluid connection with the first motor connection (<NUM>) and configured to drive a sickle knife gear box (<NUM>), the first motor (<NUM>) comprising a first motor case drain (<NUM>) being configured to connect to the combine (<NUM>); and
a second motor (<NUM>) in fluid connection with the second motor connection (<NUM>), and characterized in that the second motor (<NUM>) is configured for providing an additional forward flow to the first motor (<NUM>) in the forward state and no flow during the reverse state.