Patent Description:
The present disclosure relates to a header for an agricultural vehicle with a knife mount having a locking portion biased toward a disc surface of a rotatable disc to lock a knife.

In some exemplary embodiments disclosed herein, an agricultural vehicle, includes a chassis and a header carried by the chassis. The header includes a cutterbar with at least one cutting unit. The at least one cutting unit includes a rotary driver; a rotatable disc coupled to the rotary driver; at least one knife mount coupled to a disc surface of the rotatable disc and including a locking portion biased toward the disc surface; and a knife locked in at least one direction by the locking portion, the knife defining at least one cutting edge. The header comprises further a guard assembly held adjacent to the rotatable disc of the at least one cutting unit, the guard assembly includes a curved base portion and a plurality of extensions extending from the base portion, each of the extensions including a bottom portion and a top portion connected to the bottom portion to define a knife passage that allows the at least one knife to rotate therethrough during a full rotation of the rotatable disc. The at least one knife has a locking opening formed therein and the locking portion comprises a locking projection at least partially filling the locking opening and the header further comprising a pair of knife stops mounted to the disc surface and defining a knife slot therebetween, the at least one knife being held in the knife slot.

In some exemplary embodiments disclosed herein, a header for an agricultural vehicle according to claim <NUM>.

In some exemplary embodiments disclosed herein, a method of mounting a knife in a header for an agricultural vehicle according to claim <NUM>.

One possible benefit that may be realized by exemplary embodiments disclosed herein is the knife mount allows a knife to be quickly and easily installed or, if the knife dulls or breaks, replaced.

Another possible benefit that may be realized by exemplary embodiments disclosed herein is the knife may be pivotably locked in a knife slot so the knife does not pivot during cutting, which can improve cut quality.

Any combination and/or permutation of embodiments is envisioned. Other objects and features will become apparent from the following detailed description considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings are designed as an illustration only and not as a definition of the limits of the present disclosure.

To assist those of skill in the art in making and using the disclosed harvester and header, reference is made to the accompanying figures, wherein:.

Various terms relating to the methods and other aspects of the present disclosure are used throughout the specification and claims. Such terms are to be given their ordinary meaning in the art unless otherwise indicated. Other specifically defined terms are to be construed in a manner consistent with the definition provided herein.

As used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the content clearly dictates otherwise.

The term "plurality" as used herein is defined as any amount or number greater or more than <NUM>. In some embodiments, the term "plurality" means <NUM>, <NUM>, <NUM>, <NUM>, <NUM> or more.

The terms "left" and "right" are used herein as a matter of mere convenience, and are determined by standing at the rear of the machine facing in its normal direction of travel. Likewise, "forward" and "rearward" are determined by the normal direction of travel. "Upward" and "downward" orientations are relative to the ground or operating surface as are any references to "horizontal" or "vertical" planes or axes.

The terms "crops" and "crop material" are used herein to refer to any type of plant and/or vegetation that is intentionally planted for collection. Exemplary crops and crop material may include hay, wheat, and corn, but it should be appreciated that the embodiments disclosed herein are not limited to applications for collecting crops and crop material. Embodiments disclosed herein may be used, for example, to mow a field and sever other types of plant material such as grass, various varieties of weeds, etc..

The term "agricultural vehicle" is used herein to refer to an assembly of various elements that work in conjunction to travel and perform various tasks related to agriculture, such as removing crops, crop material, or other plant material from a field. Exemplary agricultural vehicles include, but are not limited to, vehicles that are commonly referred to as mowers, windrowers, spreaders, windrow inverters, and combine harvesters.

Many of the fastening, connection, processes and other components utilized in this disclosure are widely known and used in the field of the disclosure described, and their exact nature or type is not necessary for an understanding and use of the disclosure by a person skilled in the art, and they will not therefore be discussed in significant detail. Furthermore, the various components shown or described herein for any specific application of this disclosure can be varied and the practice of a specific application of any element may already be widely known or used in the art by persons skilled in the art and each will likewise not therefore be discussed in significant detail.

Referring now to the drawings and particularly to <FIG>, an exemplary embodiment of a self-propelled agricultural vehicle <NUM> including a tractor <NUM> carrying a forwardly disposed header <NUM> is illustrated. While the agricultural vehicle <NUM> is illustrated in the form of a self-propelled vehicle, in some embodiments the header <NUM> is included in a vehicle that is pulled or otherwise carried by, for example, a user or another vehicle. Such agricultural vehicles are well-known in the art for offering a way to sever crops or other plants. The header <NUM> includes a cutterbar <NUM> disposed adjacent the forward end of the header <NUM> to sever standings crop or other plants from the ground. The cutterbar <NUM> is carried by a header frame <NUM> that connects to a chassis <NUM> of the tractor <NUM> to allow the tractor <NUM> to push the header <NUM> across terrain. While the header <NUM> is illustrated as being pushed by the tractor <NUM>, it should be appreciated that the header <NUM> operates similarly when pulled across terrain.

Referring now to <FIG>, an exemplary embodiment of the cutterbar <NUM> is illustrated that includes a plurality of cutting units, with three cutting units 210A, 210B, 210C illustrated. It should be appreciated that while three cutting units 210A, 210B, 210C are illustrated, fewer than three cutting units, i.e., one or two cutting units, or more than three cutting units may be incorporated in the cutterbar <NUM>. In some embodiments, the cutting units 210A, 210B, 210C are positioned side-by-side across a width of the header frame <NUM>, and therefore the header <NUM>, to sever crops or other plant material across the width of the header <NUM>. Each of the cutting units 210A, 210B, 210C includes a respective rotatable disc 220A, 220B, 220C that can rotate about a respective axis of rotation AA, AB, AC when driven by one or more coupled rotary drivers, illustrated as three rotary drivers 230A, 230B, 230C. In some embodiments, the discs 220A, 220B, 220C have a rounded shape, e.g., a circular shape or an ellipsoid shape. While each of the rotatable discs 220A, 220B, 220C is illustrated as being coupled to a respective rotary driver 230A, 230B, 230C, in some embodiments multiple discs may be rotatably driven by a single rotary driver. In some embodiments, the respective axes of rotation AA, AB, AC are aligned with one another on an alignment axis A spanning the width of the header frame <NUM>, with each axis AA, AB, AC extending generally vertically relative to the ground.

To cut crop material, and referring now to <FIG> as well, at least one of the rotatable discs 220A, 220B, 220C carries one or more knives 240A, 240B, 240C during rotation. In some embodiments, each of the discs 220A, 220B, 220C carries at least two knives 240A, 240B, 240C that are equally spaced apart from adjacent knives about the respective axis of rotation AA, AB, AC. Each of the knives 240A, 240B, 240C has at least one cutting edge 241A, 242A, 241B, 242B, 241C, 242C to sever crops, crop material, or other plant material during rotation of the discs 220A, 220B, 220C. In some embodiments, each of the knives 240A, 240B, 240C has two cutting edges 241A, 242A, 241B, 242B, 241C, 242C, as illustrated, to extend the usable life of the knives 240A, 240B, 240C, which is described further herein.

Referring specifically now to <FIG>, an exemplary embodiment of a knife mount <NUM> for mounting a knife to the header <NUM> is illustrated. The knife mount <NUM> is coupled to a disc surface <NUM> of a disc, such as the disc 220A, so the disc 220A carries the knife mount <NUM> as the disc 220A rotates about its axis of rotation AA. It should be appreciated that while a single knife mount <NUM> is illustrated in <FIG>, some or all of the rotatable discs 220A, 220B, 220C may have one or more knife mounts <NUM> coupled thereto for mounting knives 240A, 240B, 240C to the rotatable discs 220A, 220B, 220C. For example, in some embodiments one or more of the discs 220A, 220B, 220C will have two or more knife mounts <NUM> for mounting two or more knives 240A, 240B, 240C to the disc(s) 220A, 220B, 220C. The knife mount <NUM> includes a locking portion <NUM> that is biased toward the disc surface <NUM> to lock a knife, such as the knife 240A, in at least one direction. As illustrated in <FIG>, for example, the locking portion <NUM> may lock the knife 240A in a pull-out direction, signified by arrow D, that extends radially relative to the axis of rotation AA so the knife 240A is not pulled away from the disc 220A while moving. In some embodiments, the locking portion <NUM> directly compresses the knife 240A against the disc surface <NUM> to lock the knife 240A. It should be appreciated that the knife 240A does not need to be compressed against the disc surface <NUM> to lock, as will be described further herein.

In some embodiments, the locking portion <NUM> is coupled to the disc surface <NUM>, which may be a bottom surface of the disc 220A, by a deflectable portion <NUM> that is mounted to the disc surface <NUM> and connected to the locking portion <NUM>. It should be appreciated that the locking portion <NUM> may be mounted to a top surface <NUM> of the disc 220A, rather than the bottom surface <NUM>. In some embodiments, the deflectable portion <NUM> includes a mounting portion <NUM> that is rigidly mounted to the disc surface <NUM> and an elastic portion <NUM> that connects to the locking portion <NUM> and comprises, for example, spring steel or another elastic material that is biased toward the disc surface <NUM>. In some embodiments, the elastic portion <NUM> is integrally formed with the locking portion <NUM> and the mounting portion <NUM> and, as illustrated in the <FIG>, has a reduced width compared to the mounting portion <NUM>.

In some embodiments, and referring again to <FIG>, the locking portion <NUM> includes a locking projection <NUM> that is sized to fit within a locking opening <NUM> formed in the knife 240A to lock the knife 240A in at least one direction. The locking projection <NUM> may have a round or other shape to define a pivoting axis, illustrated as axis PA in <FIG>, that can allow pivoting of the knife 240A about the pivoting axis PA if the knife 240A is unconstrained. In some embodiments, the knife 240A may pivot up to <NUM>° about the pivoting axis PA defined by the locking projection <NUM>.

To protect the knives 240A, 240B, 240C and other components of the header <NUM> during operation, and referring specifically to <FIG>, each cutting unit 210A, 210B, 210C may include a guard assembly 260A, 260B, 260C held adjacent to the respective cutting disc 220A, 220B, 220C of the cutting unit 210A, 210B, 210C. Each guard assembly 260A, 260B, 260C may include a plurality of extensions 261A, 261B, 261C that extend from a base portion <NUM>, which may be connected to a bottom of the cutterbar <NUM>. Each guard assembly 260A, 260B, 260C may include a bottom portion <NUM> and a top portion <NUM> connected to the bottom portion <NUM> to define a knife passage <NUM> therebetween. The knife passage <NUM> is sized, shaped, and oriented such that the knives, such as knife 240A, are allowed to pass through the knife passage <NUM> during a full rotation of the disc 220A, 220B, 220C carrying the knives. To allow passage of the knives 240A, 240B, 240C through the knife passage <NUM>, the knife passage <NUM> of each guard assembly 260A, 260B, 260C may be formed with a passage height PH that is greater than a knife thickness KT of the knives, such as knife 240A. In some embodiments, the passage height PH is between about <NUM> to about <NUM> times greater than the knife thickness KT of the knives that rotate through the knife passage. For example, in some embodiments the knife thickness KT of the knife 240A may be between about <NUM> and about <NUM> and the passage height PH may be between about <NUM> and about <NUM>. It should be appreciated that the previously described knife thickness and passage height values are exemplary only and may be modified depending on the desired cutting behavior of the knives.

During operation, each of the rotatable discs 220A, 220B, 220C may rotate about its respective axis of rotation AA, AB, AC and carry the respective knives 240A, 240B, 240C about the axis of rotation AA, AB, AC. As the knives 240A, 240B, 240C rotate, one of the cutting edges of each knife, such as cutting edges 241A, 241B, 241C, can engage and sever crop or other plant material. In some embodiments, the knives 240A, 240B, 240C are allowed to pivot about their respective pivoting axes PA, which may extend generally vertical relative to the ground.

When the cutting edges 241A, 241B, 241C initially engage material, which may be one or more plant stalks, the material will tend to deflect, i.e., bend, responsively. This deflection is more pronounced when the cut height is increased due to engagement between the cutting edges 241A, 241B, 241C and the plant material taking place further from the ground, where the plant material is supported. In some cases, the material engaged by the cutting edges 241A, 241B, 241C is also thinner, and thus more prone to bending, at greater heights from the ground. If the material being cut significantly bends when engaged by the cutting edges 241A, 241B, 241C, the cutting edges 241A, 241B, 241C may not cut the material evenly or cleanly.

As should be appreciated from <FIG>, crop slots <NUM> may be defined between opposing ledger surfaces 263A, 263B of each of the extensions 261A, 261B, 261C along the width of the cutterbar <NUM>. As the vehicle <NUM> travels through a field to sever crops or other plant material, standing plants tend to travel into and accumulate in the crop slots <NUM>. The cutting edges 241A, 241B, 241C, which travel through a portion of the crop slots <NUM>, engage accumulated material in the crop slots <NUM> as the knives 240A, 240B, 240C rotate with the discs 220A, 220B, 220C to sever the material. When the cutting edges 241A, 241B, 241C engage the material during rotation of the knives 240A, 240B, 240C, the material tends to bend in a direction of knife rotation, signified by arrow R. The ledger surface that is downstream from the material in the direction of knife rotation R, which may be the ledger surface 263A, counteracts the tendency of the material to bend by supporting the material during contact. The ledger surface 263A supporting the material allows the cutting edges 241A, 241B, 241C to cleanly and evenly cut through the material for a consistent cut. In this sense, the ledger surfaces 263A, 263B of the extensions 261A, 261B, 261C promote scissor-like cutting action by the knives 240A, 240B, 240C, similar to a reciprocating sickle-type cutter, as the knives 240A, 240B, 240C rotate.

In some embodiments, the extensions 261A, 261B, 261C, and thus the ledger surfaces 263A, 263B, comprise a metal, such as steel, that may be hardened by induction hardening, or otherwise, to reduce the effects of abrasive wear and increase the effective lifespan of the extensions 261A, 261B, 261C. In some embodiments, one or more of the ledger surfaces 263A, 263B may be coated with a high-strength material, such as tungsten carbide. To further promote scissor-like cutting action by the rotating knives 240A, 240B, 240C, one or more of the ledger surfaces 263A, 263B may be modified. In some embodiments, one or more of the ledger surfaces 263A, 263B are sharpened, i.e., beveled, or otherwise angled. In some embodiments, one or more of the ledger surfaces 263A, 263B is formed with serrations, which may be in addition to or an alternative to sharpening the ledger surface(s) 263A, 263B.

In known rotary-style cutters, the carried knives are generally free to pivot about their mounting points as they rotate with their respective discs. Due to the relatively high rotational speed of the knives and low height from the ground, such known rotary-style cutters experience little, if any, performance loss due to this pivoting because the knives cut through material, which is spread across the width of the cutterbar, relatively easily.

In a header including extensions with ledger surfaces for supporting crop or other plant material during cutting, such as exemplary embodiments of the header <NUM> disclosed herein, allowing the knives to freely pivot about their pivoting axes may detrimentally affect cutting performance. Particularly, as crop or other plant material accumulates in the crop slots <NUM>, there is a relatively high density of material that is severed by each knife 240A, 240B, 240C during a full rotation of its respective disc 220A, 220B, 220C. The relatively high density of material substantially increases the resistance that the knives 240A, 240B, 240C experience during cutting, increasing the chance that one or more of the knives 240A, 240B, 240C will excessively pivot out of a position to engage and cut through the material. The knives 240A, 240B, 240C freely pivoting also increases the risk that the knives 240A, 240B, 240C pivot into a position where the knives 240A, 240B, 240C may contact one or more of the extensions 261A, 261B, 261C during operation.

In some embodiments, and referring again to <FIG>, a pair of knife stops 471A, 471B are mounted to the disc surface <NUM> to define a knife slot <NUM> therebetween in order to minimize pivoting of the knives 240A, 240B, 240C. The locking portion <NUM> of the knife mount <NUM> may be biased toward the disc surface <NUM> such that the locking portion <NUM> at least partially resides in the knife slot <NUM> normally. A knife, such as knife 240A, may be held in the knife slot <NUM> between the knife stops 471A, 471B and locked by the locking portion <NUM>. The locking portion <NUM> can prevent the knife 240A from being pulled in the pull-out direction D while the knife stops 471A, 471B substantially prevent the knife 240A from pivoting about its pivoting axis PA, which may be a vertical axis defined by the locking projection <NUM>, or otherwise moving in a direction parallel to the disc surface <NUM>. As used herein, the knife 240A is "substantially prevented" from pivoting in the sense that the knife 240A is free to pivot by no more than <NUM>° clockwise or counterclockwise relative to its pivoting axis PA. The knife slot <NUM> may define a knife slot width KSW that is similar to a knife width KW of the knife 240A to limit the ability of the knife 240A to move during operation. In this respect, the disc surface <NUM>, the locking portion <NUM>, and the knife stops 471A, 471B can work in conjunction to rigidly lock the knife 240A to the disc 220A during rotation of the disc 220A so the knife 240A minimally translates or pivots, if at all, relative to the disc surface <NUM> during rotation. Thus, the knife stops 471A, 471B can allow the knives 240A, 240B, 240C to be pivotally locked as the discs 220A, 220B, 220C rotate to maintain the knives 240A, 240B, 240C in a generally fixed position relative to the guard assemblies 260A, 260B, 260C.

In some embodiments, and referring now to <FIG>, a support surface <NUM> may be connected to one or both of the knife stops 471A, 471B to act as a vertical support for a knife, such as the knife 240A. The support surface <NUM> may also have a back surface <NUM> connected thereto that extends toward the disc surface <NUM> to act as a backstop, which will be described further herein. The support surface <NUM> defines a clearance C, relative to the disc surface <NUM>, that may be slightly greater than the knife thickness KT of the knife 240A to limit the distance between the knife 240A and the disc surface <NUM>, and thus the vertical tilting freedom of the knife 240A. To allow locking of the knife 240A by the locking portion <NUM>, the support surface <NUM> may be formed with a through-hole that aligns with the locking opening <NUM> of the knife 240A when the knife 240A is properly oriented and allows at least a portion of the locking portion <NUM>, such as the locking projection <NUM>, to extend through both the through-hole and the locking opening <NUM> to lock the knife 240A.

Referring now to <FIG>, an exemplary embodiment of a method <NUM> for mounting a knife, such as the knife 240A, in a header, such as the header <NUM>, is illustrated. The header <NUM> includes a rotatable disc, such as the rotatable disc 220A, and a knife mount, such as the knife mount <NUM>, coupled to the rotatable disc 220A. The method <NUM> includes forcing <NUM> a locking portion <NUM> of the knife mount <NUM> away from a disc surface <NUM> of the rotatable disc 220A. The locking portion <NUM> is biased toward the disc surface <NUM> and thus resists being forced away from the disc surface <NUM>. In some embodiments, the locking portion <NUM> may be forced away from the disc surface <NUM> by a user grasping and pulling the locking portion <NUM> away from the disc surface <NUM> or by a user using a tool to pry open the locking portion <NUM>. In some embodiments, the locking portion <NUM> may be angled at its front such that pushing a surface, such as a portion of the knife 240A, against the front of the locking portion <NUM> forces the locking portion <NUM> away from the disc surface <NUM>. The locking portion <NUM> may be biased toward the disc surface <NUM> by a deflectable portion <NUM>, as previously described.

Claim 1:
A header (<NUM>) for use on an agricultural vehicle (<NUM>, <NUM>), comprising:
a header frame (<NUM>);
a cutterbar (<NUM>) with at least one cutting unit (<NUM>), the at least one cutting unit (<NUM>) comprising:
a rotary driver (<NUM>);
a rotatable disc (<NUM>) coupled to the rotary driver (<NUM>);
at least one knife mount (<NUM>) coupled to a disc surface (<NUM>) of the rotatable disc (<NUM>) and including a locking portion (<NUM>) being able to bias towards the disc surface (<NUM>); and
at least one knife (<NUM>) lockable in at least one direction by the locking portion (<NUM>), the at least one knife (<NUM>) defining at least one cutting edge (<NUM>); and
a guard assembly (<NUM>) held adjacent to the rotatable disc (<NUM>) of the at least one cutting unit (<NUM>), the guard assembly (<NUM>) including a curved base portion (<NUM>) and a plurality of extensions (<NUM>) extending from the base portion (<NUM>), each of the extensions (<NUM>) including a bottom portion (<NUM>) and a top portion (<NUM>) connected to the bottom portion (<NUM>) to define a knife passage (<NUM>) that allows the at least one knife (<NUM>) to rotate therethrough during a full rotation of the rotatable disc (<NUM>); and
characterized in that
the at least one knife (<NUM>) has a locking opening (<NUM>) formed therein and the locking portion (<NUM>) comprises a locking projection (<NUM>) at least partially filling the locking opening (<NUM>); and
in that the header (<NUM>) further comprising a pair of knife stops (<NUM>) mounted to the disc surface (<NUM>) and defining a knife slot (<NUM>) therebetween, the at least one knife (<NUM>) being held in the knife slot (<NUM>).