Patent Description:
Mowers and mower-conditioners are often employed to cut hay and/or other standing plants, such as grass, in a field. A typical mower system includes a towing vehicle, which may be a tractor or similar vehicle, that pulls a mower and/or mower-conditioner.

Many mower systems utilize so-called "offset" mowers or mower-conditioners where the mower or mower-conditioner is not carried directly behind the towing vehicle, i.e. a centerline of the mower or mower-conditioner is parallel but offset from a centerline of the towing vehicle. The mower or mower-conditioner is coupled to the towing vehicle by a pivotable tongue, which can pivot during turns. During turns, it can be difficult for a user to efficiently control the mower or mower-conditioner so there is as little underlap of uncut crop material or overlap of cut crop material as possible.

<CIT> describes an agricultural mowing system including a driving vehicle having a steerable axle and a pivotable tongue and defining a travel axis. A first mower is coupled to the front of the driving vehicle and a second mower is coupled to the tongue of the driving vehicle. A tongue actuator is configured to pivot the tongue while a tongue angle sensor is configured to output signals corresponding to a tongue angle of the tongue. A controller is operatively coupled to the tongue actuator and the tongue angle sensor. The controller is configured to determine a lateral overlap or underlap of the mowers exceeds a threshold value based at least partially on the tongue angle and a steering angle of the steerable axle, determine a correction angle needed for the tongue to pivot such that the lateral overlap or underlap no longer exceeds the threshold value and output a correction signal to the tongue actuator to pivot the tongue by the correction angle.

What is needed in the art is a way to efficiently control a mower or a mower-conditioner during a turn of the towing vehicle.

Exemplary embodiments disclosed herein provide an agricultural mower system with a controller that can determine a turn compensation amount for a mower angle as a function of a change amount of a towing angle and a constant and cause adjustment of the mower angle.

In some exemplary embodiments provided according to the present disclosure, an agricultural mower system includes: a towing vehicle including an engine and a tongue coupler, the towing vehicle defining a towing centerline; a mower including a tongue that is pivotably coupled to the tongue coupler and a frame carrying a plurality of cutters and pivotably coupled to the tongue, the frame defining a mower centerline that is offset from the towing centerline, the tongue defining a towing angle with respect to the towing centerline and a mower angle with respect to the mower centerline; a mower angle actuator coupled to the tongue and the frame and configured to pivot the frame with respect to the tongue to adjust the mower angle; a towing sensor associated with the towing vehicle and configured to output a towing angle signal corresponding to the towing angle; a mower sensor associated with the frame and configured to output a mower angle signal corresponding to the mower angle; and a controller operably coupled to the towing sensor and the mower sensor. The controller is configured to: determine the towing angle has changed by a change amount relative to a defined towing angle; determine a turn compensation amount for the mower angle as a function of the change amount and a constant; and output a compensation signal to cause the mower angle actuator to adjust the mower angle by the determined turn compensation amount.

The defined towing angle may be defined as the towing angle when the towing centerline and the mower centerline are parallel to one another.

The constant may be based at least partially on at least one geometric value of the mower.

The mower may comprise a pair of wheels defining a wheel axis and the frame pivots relative to the tongue about a pivot axis. The at least one geometric value may comprise a minimum distance between the wheel axis and the pivot axis.

The turn compensation amount may be a positive value when the change amount is a negative value.

The turn compensation amount may be a negative value when the change amount is a positive value.

An absolute value of the turn compensation amount may be equal to the function of the change amount multiplied by the constant.

The mower angle actuator may comprise a hydraulic cylinder.

The towing vehicle may comprise a hydraulic fluid system that is coupled to and powers the hydraulic cylinder. The controller may be operably coupled to the hydraulic fluid system and configured to output the compensation signal to the hydraulic fluid system.

In some embodiments, a method of adjusting a mower of an agricultural mower system is provided. The mower having a frame that is pivotably coupled to a tongue pivotably coupled to a tongue coupler of a towing vehicle. The towing vehicle includes an engine and defines a towing centerline. The mower includes a plurality of cutters carried by the frame, the frame defining a mower centerline that is offset from the towing centerline, the tongue defining a towing angle with respect to the towing centerline and a mower angle with respect to the mower centerline. The method includes: determining the towing angle has changed by a change amount relative to a defined towing angle; determining a turn compensation amount for the mower angle as a function of the change amount and a constant; and adjusting the mower angle by the determined turn compensation amount using a mower angle actuator coupled to the tongue and the mower. The mower angle actuator may be coupled to the frame and the tongue.

In some embodiments, a method of adjusting any mower disclosed herein is provided. The method includes: determining the towing angle has changed by the change amount relative to the defined towing angle; determining the turn compensation amount for the mower angle as a function of the change amount and the constant; and adjusting the mower angle by the determined turn compensation amount using the mower angle actuator.

The towing vehicle may comprise a hydraulic fluid system that is coupled to and powers the hydraulic cylinder. Adjusting the mower angle may comprise adjusting a fluid flow from the hydraulic fluid system to the hydraulic cylinder.

One possible advantage that may be realized by exemplary embodiments disclosed herein is that the controller can cause adjustment of the mower angle so the mower continues to cut crop material to an edge of the uncut crop material during a turn.

Another possible advantage that may be realized by exemplary embodiments disclosed herein is that the system is self-contained and does not need data from other sources, such as a global positioning satellite.

Another possible advantage that may be realized by exemplary embodiments disclosed herein is that user fatigue may be reduced by reducing the need for a user to anticipate how to make adjustments during a turn so the mower cuts efficiently during the turn.

Referring now to the drawings, and more particularly to <FIG>, an exemplary embodiment of an agricultural mower system <NUM> including a towing vehicle <NUM> and a mower <NUM> is illustrated. The towing vehicle <NUM> includes a chassis <NUM> and an engine, such as an internal combustion engine (ICE) <NUM>, to provide motive force to a plurality of wheels <NUM>, <NUM>. Some of the wheels, such as front wheels <NUM>, may be coupled to the chassis <NUM> by a steerable front axle <NUM> while the rear wheels <NUM> are coupled to the chassis <NUM> by a fixed rear axle <NUM>. It should be appreciated that, alternatively, the front axle <NUM> may be a fixed axle and/or the rear axle <NUM> may be a steerable axle. The towing vehicle <NUM> includes a tongue coupler <NUM> to which a tongue is pivotably coupled, as will be described further herein. The towing vehicle <NUM> defines a towing centerline TCL. As illustrated, the towing vehicle <NUM> is in the form of a tractor, but it should be appreciated that the towing vehicle <NUM> may be other types of vehicles.

The mower <NUM> includes a frame <NUM> carrying a plurality of cutters <NUM> that is pivotably coupled to a tongue <NUM> that is pivotably coupled to the tongue coupler <NUM> of the towing vehicle <NUM>. In this respect, the tongue <NUM> pivotably couples the frame <NUM> to the towing vehicle <NUM> while also being pivotable with respect to the frame <NUM>, as will be described further herein. The frame <NUM> defines a mower centerline MCL that is offset from the towing centerline TCL, as illustrated, so the mower centerline MCL is not coaxial with the towing centerline TCL. The tongue <NUM> defines a towing angle θ with respect to the towing centerline TCL and a mower angle β with respect to the mower centerline MCL, as illustrated. It should be appreciated that while the term "mower" is used to refer to the element <NUM>, the term "mower" <NUM> also encompasses what is commonly referred to as a "mower-conditioner," which includes a conditioning mechanism, e.g., a flail conditioner or a pair of conditioning rolls, to condition cut crop material.

A mower angle actuator <NUM> is coupled to the tongue <NUM> and to the frame <NUM> and configured to pivot the frame <NUM> with respect to the tongue <NUM> to adjust the mower angle β. The mower angle actuator <NUM> may be, for example, a hydraulic cylinder, an electric actuator, a pneumatic actuator, etc. A towing sensor <NUM> is associated with the towing vehicle <NUM> and configured to output a towing angle signal corresponding to the towing angle θ and a mower sensor <NUM> is associated with the frame <NUM> and configured to output a mower angle signal corresponding to the mower angle β. Each of the sensors <NUM>, <NUM> may be configured to determine the respective angle θ, β in a variety of ways, e.g., the sensors <NUM>, <NUM> may be rotary potentiometers associated with their respective elements.

As illustrated in <FIG>, the towing vehicle <NUM> and the mower <NUM> are traveling in a straight line path so the towing centerline TCL and the mower centerline MCL are parallel with one another. The relative orientation of the towing vehicle <NUM> and the mower <NUM> illustrated in <FIG> corresponds to a "normal" relative orientation, i.e., when the towing vehicle <NUM> is traveling in a straight line and not turning. In such an orientation, it is relatively easy for a user to position the mower <NUM> so the mower <NUM> has minimal overlap with previously cut crop and has no underlap so an edge E of uncut crop is cut by the cutters <NUM> of the mower <NUM>. However, when the towing vehicle <NUM> makes a turn, as illustrated in <FIG> and <FIG>, the towing angle θ changes. Without a corresponding change in the mower angle β, the mower <NUM> may not be oriented to efficiently cut the crop material without creating underlap or significant overlap with previously cut crop material.

To address some of the previously described issues, the agricultural mower system <NUM> includes a controller <NUM>, which may be carried by the towing vehicle <NUM>, that is operably coupled to the towing sensor <NUM> and the mower sensor <NUM>. The controller <NUM> is configured to determine the towing angle θ has changed by a change amount φ relative to a defined towing angle α; determine a turn compensation amount γ for the mower angle β as a function of the change amount φ and a constant; and output a compensation signal to cause the mower angle actuator <NUM> to adjust the mower angle β by the determined turn compensation amount γ. The defined towing angle α may be, for example, the towing angle θ when the towing centerline TCL and the mower centerline MCL are parallel to one another, as illustrated in <FIG>, which generally corresponds to straight-line travel of the towing vehicle <NUM> and the mower <NUM>. When the towing centerline TCL and the mower centerline MCL are parallel to one another, the mower angle β is equal to the towing angle θ, as indicated in <FIG>. In this respect, the controller <NUM> can determine when the towing vehicle <NUM> is turning, as indicated by the change in the towing angle θ relative to the defined towing angle α, and cause the mower angle actuator <NUM> to adjust the mower angle β by the turn compensation amount γ so the mower <NUM> continues to cut the edge E of uncut crop as the towing vehicle <NUM> navigates the radius of the turn.

Referring specifically to <FIG>, the situation is illustrated in which the towing vehicle <NUM> is turning opposite to the offset of the mower <NUM>, i.e., the towing vehicle <NUM> is turning left while the mower <NUM> is offset to the right. It should be appreciated that an analogous situation would be presented if the mower <NUM> were offset to the left and the towing vehicle <NUM> were turning to the right. During such a turn, it can be seen that the towing angle θ decreases by the change amount φ relative to the defined towing angle α. To compensate for this decrease in the towing angle θ, the controller <NUM> determines that the turn compensation amount γ should be a positive value that is added to the mower angle β in order for the mower <NUM> to steer away from the towing vehicle <NUM> and follow the larger radius of the uncut crop, which maintains engagement with the edge E of the uncut crop. In other words, the turn compensation amount γ may be a positive value when the change amount φ is a negative value.

The determined turn compensation amount γ is based on a function of the change amount φ as well as a constant. The function of the change amount, which may be defined as f(φ), may be based on several parameters, including but not limited to a speed of the towing vehicle <NUM>, a turn radius of the towing vehicle <NUM>, a turn radius of the mower <NUM>, etc. Thus, it should be appreciated that the function of the change amount f(φ) will vary based on parameters of the agricultural mower system <NUM>. The constant may be a constant based at least partially on at least one geometric value of the mower <NUM>. For example, the mower <NUM> may include a pair of wheels <NUM> defining a wheel axis WA and the frame <NUM> may pivot relative to the tongue <NUM> about a pivot axis PA. The at least one geometric value of the mower <NUM> on which the constant is based may be a minimum distance D between the wheel axis WA and the pivot axis PA, as illustrated in <FIG>. Thus, the constant may be based on one or more geometric values of the mower <NUM> that have an effect on the turn radius of the mower <NUM> in order for the mower angle β to be properly adjusted to compensate for the change in turn radius of the towing vehicle <NUM>. In some embodiments, an absolute value of the turn compensation amount γ is equal to the function of the change amount f(φ) multiplied by the constant, designated as c, i.e., |γ| = f(φ) * c.

Referring now to <FIG>, the situation is illustrated in which the towing vehicle <NUM> is turning in the same direction as the offset of the mower <NUM>, i.e., the mower <NUM> is offset on the right and the towing vehicle <NUM> is turning right. It should be appreciated that an analogous situation arises when the mower <NUM> is offset on the left and the towing vehicle <NUM> turns to the left. In such a situation, the towing angle θ increases compared to the defined towing angle α, i.e., the change amount φ is a positive value. Consequently, the turn compensation amount γ for the mower angle β is a negative value so the mower <NUM> follows the turn radius of the uncut crop and stays in engagement with the edge E. Similarly to the situation illustrated in <FIG>, the turn compensation amount γ for the mower angle β is a function of the change amount φ and the constant, which may be based on one or more geometric values of the mower <NUM>.

In the scenario where the defined towing angle α is equal to the towing angle θ when the towing centerline TCL is parallel to the mower centerline MCL, in which case the mower angle β is also equal to the towing angle θ, the value for the mower angle β may be determined based on the measured towing angle θ. For example, in <FIG>, there is no change amount φ relative to the defined towing angle α, i.e., φ is equal to zero, so the mower angle β is equal to the towing angle θ with a function of change amount φ of zero, i.e., the mower angle β is equal to the towing angle θ. In the subsequent scenarios illustrated in <FIG>, the mower angle β may be adjusted from the baseline mower angle β, which is equal to the towing angle θ and the defined towing angle α, by the turn compensation amount γ, which is a function of the change amount φ and the constant. It should thus be appreciated that, in some embodiments, the turn compensation amount γ for the mower angle β can be determined based on the change amount φ of the measured towing angle θ as well as the constant when the towing vehicle <NUM> is turning from straight-line travel. It should be further appreciated that the controller <NUM> provided according to the present disclosure can also readily determine the turn compensation amount γ for the mower angle β in the situation where the towing vehicle <NUM> makes a turn and then makes another turn before going to straight-line travel, i.e., during a compound turn, to maintain engagement between the mower <NUM> and the edge E of uncut crop.

In some embodiments, the controller <NUM> is configured to toggle between a mode where the controller <NUM> determines the turn compensation amount γ and causes a corresponding adjustment of the mower angle β or not, i.e., the turn compensation may be turned off by a user. In some embodiments, the user may select a button on a display or similar device that causes the controller <NUM> to enter the turn compensation mode and perform the previously described functions. In some embodiments, the defined towing angle α is a preset angle value that is stored in a memory or elsewhere and is recalled by the controller <NUM> during operation. In some embodiments, the defined towing angle α is set by the user, either as a direct input or as a value determined by the controller <NUM>. For example, the user may control the towing vehicle <NUM> so the towing centerline TCL and the mower centerline MCL are parallel to one another in the desired offset relationship. The user may then make a selection on a display (or other device) that the towing vehicle <NUM> and the mower <NUM> are in a desired offset relationship. The controller <NUM> may then request the towing angle signal from the towing sensor <NUM> to determine the current towing angle θ, which the controller <NUM> then defines as the defined towing angle α. In some embodiments, the controller <NUM> also simultaneously requests the mower angle signal from the mower sensor <NUM> to determine the current mower angle β, which the controller <NUM> then defines as a base mower angle. It should thus be appreciated that the defined towing angle α may be defined in a variety of ways according to the present disclosure.

In some embodiments, as previously described, the mower angle actuator <NUM> is a hydraulic cylinder that extends or retracts to adjust the mower angle β. To control the mower angle actuator <NUM>, and thus the mower angle β, the towing vehicle <NUM> may include a hydraulic fluid system <NUM> that is coupled to and powers the mower angle actuator <NUM>. The hydraulic fluid system <NUM> may, for example, couple to a hydraulic coupler on the tongue <NUM> that couples to the mower angle actuator <NUM>, fluidly coupling the hydraulic fluid system <NUM> to the mower angle actuator <NUM>. The controller <NUM> may be operably coupled to the hydraulic fluid system <NUM> and configured to output the compensation signal to the hydraulic fluid system <NUM>, which may then adjust fluid flow to the mower angle actuator <NUM> to cause a corresponding extension or retraction and change in the mower angle β. For example, the controller <NUM> may output a compensation signal to the hydraulic fluid system <NUM> that causes one or more valves of the hydraulic fluid system <NUM> to open, increasing the fluid pressure provided to the mower angle actuator <NUM> and causing a corresponding extension. The extension of the mower angle actuator <NUM> may cause the mower angle β to increase, which the controller <NUM> can monitor via mower angle signals from the mower sensor <NUM>. If the controller <NUM> determines that the mower angle β has not adjusted by the determined turn compensation amount γ, which may be due to unexpectedly high resistance to pivoting of the frame <NUM>, the controller <NUM> may output a corrective signal to the hydraulic fluid system <NUM> to further increase the fluid pressure provided to the mower angle actuator <NUM>. In this respect, the controller <NUM> may be configured to monitor the mower angle β following outputting the compensation signal to ensure that the mower angle β is adjusted by the determined turn compensation amount γ based on feedback from various inputs.

From the foregoing, it should be appreciated that the controller <NUM> of the agricultural mower system <NUM> provided according to the present disclosure can automatically determine the proper turn compensation amount γ for the mower angle β when the towing angle θ deviates from the defined towing angle α and cause a change in the mower angle β so the mower <NUM> stays in proper engagement with an edge E of uncut crop material during a turn. The controller <NUM> thus reduces the risk of a user misjudging how to maneuver the towing vehicle <NUM> and the mower <NUM> to keep the mower <NUM> in engagement with the edge E of uncut crop material. The controller <NUM> can also reduce the fatigue a user experiences during operation by alleviating the need for the user to plan and execute complex turn maneuvers in the field.

Referring now to <FIG>, an exemplary embodiment of a method <NUM> for adjusting the mower <NUM> of the agricultural mower system <NUM> provided according to the present disclosure is illustrated. The method <NUM> includes determining <NUM> the towing angle θ has changed by the change amount φ relative to the defined towing angle α; determining <NUM> the turn compensation amount γ for the mower angle β as a function of the change amount φ and the constant; and adjusting <NUM> the mower angle β by the determined turn compensation amount γ using the mower angle actuator <NUM> coupled to the frame <NUM> and the tongue <NUM>. In some embodiments, adjusting <NUM> the mower angle β includes adjusting a fluid flow from the hydraulic fluid system <NUM> to the mower angle actuator <NUM>, which may be a hydraulic cylinder. The steps <NUM>, <NUM>, <NUM> of the method <NUM> may be performed by the previously described controller <NUM>. Further, the method <NUM> may include steps directed toward any of the previously described functionality of the controller <NUM> and/or other components of the agricultural mower system <NUM>.

It is to be understood that the steps of the method <NUM> may be performed by the controller <NUM> upon loading and executing software code or instructions which are tangibly stored on a tangible computer readable medium, such as on a magnetic medium, e.g., a computer hard drive, an optical medium, e.g., an optical disc, solid-state memory, e.g., flash memory, or other storage media known in the art. Thus, any of the functionality performed by the controller <NUM> described herein, such as the method <NUM>, is implemented in software code or instructions which are tangibly stored on a tangible computer readable medium. The controller <NUM> loads the software code or instructions via a direct interface with the computer readable medium or via a wired and/or wireless network. Upon loading and executing such software code or instructions by the controller <NUM>, the controller <NUM> may perform any of the functionality of the controller <NUM> described herein, including any steps of the method <NUM> described herein.

Claim 1:
An agricultural mower system (<NUM>), comprising:
a towing vehicle (<NUM>) comprising an engine (<NUM>) and a tongue coupler (<NUM>), the towing vehicle (<NUM>) defining a towing centerline (TCL);
a mower (<NUM>) comprising a tongue (<NUM>) that is pivotably coupled to the tongue coupler (<NUM>) and a frame (<NUM>) carrying a plurality of cutters (<NUM>) and pivotably coupled to the tongue (<NUM>), the frame (<NUM>) defining a mower centerline (MCL) that is offset from the towing centerline (TCL), the tongue (<NUM>) defining a towing angle (Θ) with respect to the towing centerline (TCL) and a mower angle (β) with respect to the mower centerline (MCL);
a mower angle actuator (<NUM>) coupled to the tongue (<NUM>) and the frame (<NUM>) and configured to pivot the frame (<NUM>) with respect to the tongue (<NUM>) to adjust the mower angle (β);
a mower sensor (<NUM>) associated with the frame (<NUM>) and configured to output a mower angle signal corresponding to the mower angle (β); and
a controller (<NUM>);
characterized by:
a towing sensor (<NUM>) associated with the towing vehicle (<NUM>) and configured to output a towing angle signal corresponding to the towing angle (θ); and
the controller (<NUM>) operably coupled to the towing sensor (<NUM>) and the mower sensor (<NUM>), the controller (<NUM>) being configured to:
determine that the towing angle (Θ) has changed by a change amount (φ) relative to a defined towing angle (α);
determine a turn compensation amount (γ) for the mower angle (β) as a function of the change amount (φ) and a constant; and
output a compensation signal to cause the mower angle actuator (<NUM>) to adjust the mower angle (β) by the determined turn compensation amount (γ).