Patent Description:
According to the invention, there is provided an agricultural row unit as defined in claim <NUM>. Further optional features of the agricultural row unit according to the invention are set out in the claims dependent on claim <NUM>.

Referring now to the drawings, wherein like reference numerals designate identical or corresponding parts throughout the several views, <FIG> illustrates an agricultural implement, e.g., a planter, comprising a toolbar <NUM> to which multiple row units <NUM> are mounted in transversely spaced relation. Each row unit <NUM> is preferably mounted to the toolbar by a parallel arm arrangement <NUM> such that the row unit is permitted to translate vertically with respect to the toolbar. An actuator <NUM> is pivotally mounted to the toolbar <NUM> and the parallel arm arrangement <NUM> and configured to apply supplemental downpressure to the row unit <NUM>.

The row unit <NUM> includes a frame <NUM>. The row unit <NUM> includes an opening disc assembly <NUM> including two angled opening discs <NUM> rollingly mounted to a downwardly extending shank <NUM> of the frame <NUM> and disposed to open a v-shaped trench <NUM> (i.e., furrow, seed furrow) in a soil surface <NUM> as the row unit traverses a field. The row unit <NUM> preferably includes a gauge wheel assembly <NUM> including two gauge wheels <NUM> pivotally mounted to either side of the frame <NUM> by two gauge wheel arms <NUM> and disposed to roll along the surface of the soil. A depth adjustment assembly <NUM> pivotally mounted to the frame <NUM> at a pivot <NUM> preferably contacts the gauge wheel arms <NUM> to limit the upward travel of the gauge wheel arms <NUM>, thus limiting the depth of the trench opened by the opening disc assembly <NUM>. A closing assembly <NUM> is preferably pivotally coupled to the frame <NUM> and configured to move soil back into the trench <NUM>.

Continuing to refer to <FIG>, seeds <NUM> are communicated from a hopper <NUM> to a seed meter <NUM> preferably configured to singulate the supplied seeds. The meter <NUM> is preferably a vacuum-type meter such as that disclosed in Applicant's <CIT>. In operation, the seed meter <NUM> preferably deposits the supplied seeds into a seed tube <NUM>. The seed tube <NUM> is preferably removably mounted to the frame <NUM>; in operation, seeds <NUM> deposited by the meter <NUM> fall through the seed tube <NUM> into the trench <NUM>.

Turning to <FIG>, a not according to the invention depth adjustment assembly <NUM> is illustrated in more detail. The depth adjustment assembly <NUM> includes a rocker <NUM> pivotally mounted to a depth adjustment body <NUM>. The depth adjustment body <NUM> is pivotally mounted to the row unit frame <NUM> about the pivot <NUM>. A handle <NUM> is preferably slidably received within the depth adjustment body <NUM> such that the user can selectively engage and disengage the handle (e.g., left and right hooks <NUM>-<NUM>, <NUM>-<NUM>, respectively, which may be formed as a part of the handle <NUM>) with one of a plurality of depth adjustment slots <NUM> (<FIG>) formed within the row unit frame <NUM>. With reference to <FIG>, the handle <NUM> is partially slidingly received within a cavity <NUM> of the depth adjustment body <NUM>, and an optional spring <NUM> engages an annular lip <NUM> disposed on the bottom end of the handle <NUM>; the spring <NUM> thus imposes a resilient force to retain the hooks <NUM> in the selected slot <NUM> but permits the user to withdraw the handle <NUM> to temporarily disengage the hooks <NUM> from the slot <NUM>. In operation, the upward travel of the gauge wheels <NUM> is limited by contact of the gauge wheel arms <NUM> with the rocker <NUM>. When one of the gauge wheels, e.g., left gauge wheel <NUM>-<NUM>, encounters an obstruction, the rocker <NUM> allows the left gauge wheel arm <NUM>-<NUM> to travel upward while lowering the right gauge wheel <NUM>-<NUM> by the same absolute displacement such that the row unit <NUM> rises by half the height of the obstruction.

It should be appreciated that the handle <NUM> and depth adjustment body <NUM> comprise a primary depth adjustment sub-assembly configured to permit the user to select one of a plurality of pre-selected furrow depths. The pre-selected furrow depths each correspond to one of the depth adjustment slots <NUM>. In some examples, rather than using the handle <NUM> to manually select a depth adjustment slot, an actuator may be used to adjust the position of handle <NUM>; for example, a linear actuator (not shown) mounted to the row unit frame <NUM> may be disposed to adjust the position of the handle <NUM>, or a rotary actuator may turn a gear which adjusts the position of the handle relative to the depth adjustment slots <NUM>.

In each of the examples illustrated in <FIG> and <FIG>, a secondary not according to the invention depth adjustment assembly is configured to modify one or more of the pre-selected furrow depths. The secondary depth adjustment assembly may modify the pre-selected furrow depths by more precise adjustments (e.g., by smaller adjustment steps) than the depth modifications enabled by the primary depth adjustment assembly (e.g., by selecting which depth adjustment slot <NUM> is engaged by the handle <NUM>). For example, referring <FIG>, the depth adjustment assembly 90A includes an actuator <NUM> which adjusts the effective length of the depth adjustment assembly 90A. In the illustrated example, the extension of actuator <NUM> determines the position of the rocker <NUM> relative to the depth adjustment body <NUM>. As illustrated, the rocker <NUM> is pivotally mounted to a movable member <NUM> having a cavity <NUM> for receiving a protrusion <NUM> preferably mounted to (or formed as a part with) the depth adjustment body <NUM>. The protrusion <NUM> and cavity <NUM> retain the alignment of the moveable member relative to the depth adjustment body <NUM>, but permit the actuator <NUM> to modify the position along an axis which is preferably parallel to the pivot axis of the rocker <NUM>. It should be appreciated that modification of the extension of actuator <NUM> (and thus the effective length of the depth adjustment assembly) modifies the furrow depth for any given depth setting of the handle <NUM>. Any of the secondary depth adjustment assemblies described herein can be used as the only depth adjustment. The primary depth adjustment does not need to be set. The secondary depth adjustment can adjust across the entire range of depth setting.

<FIG> illustrates another example of a depth adjustment assembly 90B having a secondary depth adjustment assembly wherein an actuator <NUM> modifies the angular position at which one or more gauge wheel arms <NUM> is stopped by the depth adjustment assembly 90B for any given setting of the depth adjustment handle <NUM>. The actuator <NUM> preferably adjusts a position of a surface <NUM> which is pivotally mounted to the gauge wheel arm <NUM>; the surface <NUM> is preferably disposed to contact the rocker <NUM> at the point of maximum upward travel of the gauge wheel arm <NUM>. Extension of the actuator <NUM> and thus modification of the position of surface <NUM> thus preferably modifies the point of maximum upward travel of the gauge wheel and thus modifies the furrow depth determined by the gauge wheel. In some examples, a functionally similar actuator <NUM> and pivotally-mounted surface <NUM> may be mounted to both gauge wheel arms <NUM>.

<FIG> illustrates another example of a depth adjustment assembly 90C having a secondary depth adjustment assembly wherein a modified rocker <NUM> is configured to modify its shape in order to modify the furrow depth for any given depth setting of the handle <NUM>. The rocker <NUM> preferably includes portions <NUM>-<NUM>, <NUM>-<NUM> which contact the gauge wheel arms <NUM>-<NUM> and <NUM>-<NUM>, respectively, to limit the upward travel of the gauge wheel arms. An actuator <NUM> preferably changes the angle between the portions <NUM>-<NUM> and <NUM>-<NUM> and thus the shape of the rocker <NUM>. Retraction of the actuator <NUM> preferably raises the members <NUM> and thus modifies the maximum height of the gauge wheel arms <NUM> and the furrow depth.

<FIG> illustrates another example of a depth adjustment assembly 90D having a secondary depth adjustment assembly wherein the rocker <NUM> is pivotally mounted to the depth adjustment body <NUM>, preferably about a laterally extending axis defined by pivot <NUM>. An actuator <NUM> preferably determines the angular position of the rocker <NUM> about the pivot <NUM> relative to the depth adjustment body <NUM>, thus modifying the maximum upward travel of the gauge wheel arms <NUM> and the furrow depth.

<FIG> illustrates an alternative to the example illustrated in <FIG>. Pivot <NUM> is removed, and rocker <NUM> is attached to connector <NUM>, which pivots about pivot <NUM>.

<FIG> illustrates another example of a depth adjustment assembly 90E having a secondary depth adjustment assembly wherein an actuator <NUM> advances a depth adjustment member <NUM> (e.g., a wedge) which is preferably slidingly fixed to the gauge wheel arm and disposed to slide along the length of the gauge wheel arm <NUM>. An actuator <NUM> (e.g., a linear actuator such as an electric, hydraulic, or pneumatic actuator) preferably selectively modifies (e.g., by extension or retraction) the position of the depth adjustment member <NUM>, e.g., along the length of the gauge wheel arm <NUM>. The position of the depth adjustment member <NUM> along the length of the gauge wheel arm preferably modifies the uppermost angular position of the gauge wheel arm relative to the rocker <NUM> and thus preferably modifies the depth of the furrow opened by the row unit in operation. The actuator <NUM> may be mounted to the gauge wheel arm <NUM>, e.g., by being fixed to a plate <NUM> mounted to the gauge wheel arm <NUM>.

In some examples, the actuator <NUM> may adjust the position of the depth adjustment member <NUM> by means of a biasing mechanism. The biasing mechanism preferably increases or reduces a biasing force on the wedge <NUM> as the actuator <NUM> is extended. For example, as illustrated in <FIG>, the actuator <NUM> may modify a position of a biasing member such as a plate <NUM> relative to the depth adjustment member <NUM>. Optionally, a first spring 1215a is preferably fixed to the depth adjustment member <NUM> at a first end thereof and is preferably fixed to the plate <NUM> at a second end thereof. Optionally, a second spring 1215b is preferably fixed to the plate <NUM> at a first end thereof and is preferably fixed to the plate <NUM> at a second end thereof. In the undeflected position shown in <FIG>, preferably neither of the springs 1215a, 1215b impose a substantial force on the biasing member <NUM>. As the actuator <NUM> advances from the undeflected position, the spring imposes an increasing advancing force on the biasing member <NUM> (e.g., generally toward the rocker <NUM>). As the actuator <NUM> retracts from the undeflected position, the spring imposes an increasing retracting force on the biasing member <NUM> (e.g., generally away from the rocker <NUM>).

In operation, when a component of force transmitted from the actuator <NUM> (e.g., via the spring 1215a of the biasing mechanism illustrated in <FIG>) to the rocker <NUM> exceeds an oppositely acting force of the rocker <NUM> on the gauge wheel arm (or on the depth adjustment member if the rocker is already contacting the depth adjustment member), the depth adjustment member <NUM> preferably advances, forcing the rocker <NUM> farther away from the gauge wheel arm and reducing the furrow depth. It should be appreciated that the biasing force may be built up gradually by extension of the actuator <NUM> without being sufficient to advance the depth adjustment member <NUM> until sufficient extension of the actuator or until reduction of downforce.

<FIG> are perspective views of a row unit frame <NUM> showing alternative examples of depth adjustment assemblies 90F and <NUM>, respectively, disposed on the row unit <NUM>.

Referring to <FIG>, a side elevation view of depth adjustment assembly 90F is shown as viewed along lines X-X of <FIG>. <FIG> is an enlarged perspective view of depth adjustment assembly 90F with the row unit frame <NUM> removed and the handle <NUM> shown in dashed lines for clarity.

The depth adjustment assembly 90F includes a housing <NUM> which is received between the sidewalls of the row unit frame <NUM>. The housing <NUM> is adjustably positionable along the depth adjustment slots <NUM> of the row unit frame <NUM> by engagement of the handle <NUM> within one of the plurality of depth adjustment slots <NUM> to achieve the initial preselected furrow depth. The handle <NUM> includes hooks <NUM>-<NUM>, <NUM>-<NUM> which extend into the slots <NUM>, thereby positioning the housing <NUM> at the desired slot <NUM>.

The secondary depth adjustment assembly of the depth adjustment assembly 90F comprises a drive motor <NUM>, drive screw <NUM>, drive member <NUM>, cam arm <NUM> and cog <NUM>, all of which cooperate to adjustably position the rocker <NUM> with respect to the row unit frame <NUM> as hereinafter described.

As shown in <FIG>, the drive screw <NUM> extends into the housing <NUM> and is driven by the drive motor <NUM>. The drive screw <NUM> is threadably received by the drive member <NUM>. The cog <NUM> is rotatably disposed on drive member <NUM>. A cam arm <NUM> has a proximal end <NUM> and a distal end <NUM>. The distal end <NUM> of the cam arm <NUM> is pivotably mounted about pivot <NUM>. The proximal end <NUM> of the cam arm <NUM> includes teeth <NUM> that engage with the cog <NUM>. The rocker <NUM> is pivotally attached to the distal end <NUM> of the cam arm <NUM>. Stops <NUM>-<NUM> and <NUM>-<NUM> may be disposed in the housing <NUM> on either side of cam arm <NUM> to limit the rotational movement of cam arm <NUM> in both the clockwise and counterclockwise rotation.

In operation, drive motor <NUM> rotates the drive screw <NUM> causing the drive member <NUM> threadably attached thereto to be threaded upwardly or downwardly along the drive screw <NUM> such that it is raised and lowered within the housing <NUM>. If the drive screw <NUM> is rotated by the drive motor <NUM> in the direction to cause the drive member <NUM> to be threaded upwardly along the drive screw <NUM>, the cog <NUM> engages with the teeth <NUM> of the cam arm <NUM> causing the cam arm <NUM> to pivot counterclockwise (as shown in <FIG>) about pivot <NUM>, which raises the rocker <NUM> with respect to the row unit frame <NUM>, permitting the gauge wheel arms <NUM> to raise with respect to the frame member <NUM>, thereby increasing the furrow depth. Conversely, if the drive screw <NUM> is rotated by the drive motor <NUM> in the opposite direction to cause the drive member <NUM> to be threaded downwardly along the drive screw <NUM>, the cog <NUM> engages with the teeth <NUM> of the cam arm <NUM> causing the cam arm <NUM> to pivot clockwise (as shown in <FIG>) about pivot <NUM>, which forces the rocker <NUM> lower with respect to the frame member <NUM>, thereby forcing the gauge wheel arms <NUM> downwardly with respect to the frame member <NUM> and, in turn, decreasing the furrow depth.

Referring to <FIG>, a side elevation view of depth adjustment assembly <NUM> is shown as viewed along lines Y-Y of <FIG>. Similar to the example of 90F, the depth adjustment assembly <NUM> includes a housing <NUM> which is received between the sidewalls of the row unit frame <NUM>. The housing <NUM> is adjustably positionable along the depth adjustment slots <NUM> of the row unit frame <NUM> by engagement of the handle <NUM> within one of the plurality of depth adjustment slots <NUM> to achieve the initial preselected furrow depth. The handle <NUM> includes pegs <NUM> which extend into the slots <NUM> thereby securing the housing <NUM> at the desired slot <NUM>.

The secondary depth adjustment assembly of the depth adjustment assembly <NUM> comprises a drive motor <NUM>, drive screw <NUM>, drive member <NUM>, cam arm <NUM> and a roller <NUM> (<FIG>) or a cog <NUM> (<FIG>), which cooperate to adjustably position the rocker <NUM> with respect to the row unit frame <NUM> as hereinafter described.

As shown in <FIG>, the drive screw <NUM> extends into the housing <NUM> and is driven by a drive motor <NUM>. The drive screw <NUM> is threadably received by drive member <NUM>. The drive member <NUM> has a sloped side <NUM> that engages with a roller <NUM> rotatably attached to a proximal end <NUM> of the cam arm <NUM>. A distal end <NUM> of the cam arm <NUM> is pivotably mounted about pivot <NUM>. The rocker <NUM> is pivotally attached to the distal end <NUM> of the cam arm <NUM>. In an alternative example shown in <FIG>, roller <NUM> is be replaced with a rotatable cog <NUM> and the sloped side <NUM> includes teeth <NUM> which engage with the cog <NUM> as the cog <NUM> rotates. Stops <NUM>-<NUM> and <NUM>-<NUM> may be disposed in the housing <NUM> on either side of cam arm <NUM> to limit the rotational movement of cam arm <NUM> in both the clockwise and counterclockwise rotation.

In operation, the drive motor <NUM> rotates the drive screw <NUM> causing the drive member <NUM> threadably attached thereto to be threaded upwardly or downwardly along the drive screw <NUM> such that it is raised and lowered within the housing <NUM>. If the drive screw <NUM> is rotated by the drive motor <NUM> in the direction to cause the drive member <NUM> to be threaded upwardly along the drive screw <NUM>, the roller <NUM> will roll downwardly along the sloped side <NUM> causing the cam arm <NUM> to pivot counterclockwise (as shown in <FIG>) about pivot <NUM>, which raises the rocker <NUM> with respect to the row unit frame <NUM>, permitting the gauge wheel arms <NUM> to raise with respect to the frame member <NUM>, thereby increasing the furrow depth. Conversely, if the drive screw <NUM> is rotated by the drive motor <NUM> in the opposite direction to cause the drive member <NUM> to be threaded downwardly along the drive screw <NUM>, the roller <NUM> will roll along the curved surface <NUM> causing the cam arm <NUM> to pivot clockwise (as shown in <FIG>) about pivot <NUM>, which forces the rocker <NUM> lower with respect to the frame member <NUM>, thereby forcing the gauge wheel arms <NUM> downwardly with respect to the frame member <NUM> and, in turn, decreasing the furrow depth. It should be appreciated that with respect to the example shown in <FIG>, wherein the roller <NUM> and sloped surface <NUM> are replaced with the cog <NUM> which engage teeth <NUM> on the sloped surface <NUM>, the same action is accomplished.

Any of the actuators (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) can be electrical, hydraulic, or pneumatic actuators.

<FIG> and <FIG> illustrate an embodiment of a depth adjustment assembly <NUM> in accordance with the invention in which a rotary actuator <NUM> (such as an electric motor) turns gears <NUM>-<NUM> and <NUM>-<NUM> that adjusts the position of the depth adjustment body <NUM> relative to the depth adjustment slots <NUM>. Gears <NUM>-<NUM> and <NUM>-<NUM> have teeth <NUM>-<NUM> and <NUM>-<NUM>, respectively that engage in slots <NUM>. Rotary actuator <NUM> is connected to depth adjustment body <NUM>, which is pivotally mounted to the frame <NUM> at pivot <NUM>. Rocker <NUM> is pivotally mounted to the depth adjustment body <NUM>. Rotary actuator may be gear reduced (such as <NUM>:<NUM>) to allow for smaller rotation of gears <NUM>-<NUM> and <NUM>-<NUM>. In this embodiment, rotary actuator <NUM> replaces handle <NUM>. This embodiment can be used as the only depth adjustment assembly, or it can be used as the primary depth adjustment assembly and used in combination with any of the other secondary depth adjustment assemblies.

<FIG> illustrates an alternative embodiment of a depth adjustment assembly <NUM> in which depth adjustment body <NUM> is replaced with depth adjustment body <NUM>, handle shaft <NUM>, and spring <NUM>. Handle shaft <NUM> is attached to actuator <NUM> and is partially slidingly received within a cavity <NUM> of the depth adjustment body <NUM>. The spring <NUM> engages an annular lip <NUM> disposed on the bottom end of the handle shaft <NUM>. The spring <NUM> thus imposes a resilient force to retain the gears <NUM> in the selected slot <NUM> but permits the user to withdraw the actuator <NUM> using handle <NUM> attached to actuator <NUM> to temporarily disengage the gears <NUM> from the slot <NUM> to a desired pre-set depth to minimize the amount of travel that the actuator <NUM> needs to reach a selected depth.

The depth adjustment actuators/motors (e.g., secondary depth adjustment actuators/motors) disclosed herein (e.g., actuators/motors <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) may be in data communication with a depth control and soil monitoring system <NUM> as illustrated in <FIG> and described herein.

In the system <NUM>, a monitor <NUM> is preferably in electrical communication with components associated with each row unit <NUM> including seed meter drives <NUM>, seed sensors <NUM>, the GPS receiver <NUM>, downforce sensors <NUM>, downforce valves <NUM>, depth adjustment actuators <NUM>, and depth actuator encoders <NUM> (and in some examples actual depth sensors <NUM> such as those described in applicant's <CIT>). In some examples, particularly those in which each seed meter <NUM> is not driven by an individual drive <NUM>, the monitor <NUM> is also preferably in electrical communication with clutches <NUM> configured to selectively operably couple the seed meter <NUM> to the drive <NUM>.

Continuing to refer to <FIG>, the monitor <NUM> is preferably in electrical communication with a cellular modem <NUM> or other component configured to place the monitor <NUM> in data communication with the Internet, indicated by reference numeral <NUM>. Via the Internet connection, the monitor <NUM> preferably receives data from a soil data server <NUM>. The soil data server <NUM> preferably includes soil map files (e.g., shape files) associating soil types (or other soil characteristics) with GPS locations. In some examples, soil map files are stored in the memory of the monitor <NUM>.

The monitor <NUM> is also preferably in electrical communication with one or more temperature sensors <NUM> mounted to the planter and configured to generate a signal related to the temperature of soil being worked by the planter row units <NUM>. In some examples one or more of the temperature sensors <NUM> comprise thermocouples disposed to engage the soil as disclosed in Applicant's International Patent Pub. In such examples the temperature sensors <NUM> preferably engage the soil at the bottom of the trench <NUM>. In other arrangements, one or more of the temperature sensors <NUM> may comprise a sensor disposed and configured to measure the temperature of the soil without contacting the soil as disclosed in International Patent Pub.

Referring to <FIG>, the monitor <NUM> is preferably in electrical communication with one or more moisture sensors <NUM> mounted to the planter and configured to generate a signal related to the temperature of soil being worked by the planter row units <NUM>. In some arrangements, the moisture sensor <NUM> comprises a reflectance sensor such as that disclosed in <CIT>. In such arrangements, the moisture sensor <NUM> is preferably mounted to the shank <NUM> of the row unit <NUM> and disposed to measure the soil moisture at the bottom of the trench <NUM>, preferably at a position longitudinally forward of the seed tube <NUM>. The monitor <NUM> is preferably in electrical communication with one or more second-depth moisture sensors <NUM>. The second-depth moisture sensor <NUM> preferably comprises a reflectance sensor such as that disclosed in the '<NUM> application, disposed to measure soil moisture at a depth at which consistent moisture reading is expected. In some embodiments the second-depth moisture sensor <NUM> is disposed to measure soil moisture at a greater depth than used for planting, such as between <NUM> and <NUM> inches and preferably approximately <NUM> inches below the soil surface. In other configurations the second-depth moisture sensor <NUM> is disposed to measure soil moisture at a lesser depth than used for planting, such as between <NUM> inch and <NUM> inch and preferably approximately <NUM> inch below the soil surface. The second-depth moisture sensor <NUM> is preferably disposed to open a trench laterally offset from the trenches <NUM> opened by the row units <NUM>.

Referring to <FIG>, the monitor <NUM> is preferably in electrical communication with one or more electrical conductivity sensors <NUM>. The electrical conductivity sensor <NUM> preferably comprises one or more electrodes disposed to cut into the soil surface such as the sensors disclosed in <CIT> and<CIT>.

Referring to <FIG>, the monitor <NUM> is preferably in electrical communication with one or more pH sensors <NUM>. In some embodiments the pH sensor <NUM> is drawn by a tractor or by another implement (e.g., a tillage implement) such that data is stored in the monitor <NUM> for later use. In some such arrangements, the pH sensor <NUM> is similar to that disclosed in <CIT>. In some arrangements, the pH sensor <NUM> is mounted to the toolbar <NUM>, preferably at a position laterally offset from the row units <NUM>.

Claim 1:
An agricultural row unit (<NUM>), comprising:
a row unit frame (<NUM>) configured with opening discs (<NUM>) to open a furrow (<NUM>) having a furrow depth;
a depth adjustment assembly (<NUM>) configured to modify said furrow depth,
a depth adjustment body (<NUM>;<NUM>) pivotally connected via a pivot (<NUM>) to the row unit frame characterized in that it further comprises
gears (<NUM>) configured for engagement in slots (<NUM>) formed within the row unit frame;
a rotary actuator (<NUM>) in the form of an electric motor (<NUM>) configured to rotatably drive said gears (<NUM>) to adjust the position of the depth adjustment body relative to the slots and modify said furrow depth.