Patent Description:
Forages, such as grasses, legumes, maize, and other crop residues, are commonly cut by a cutter implement, such as but not limited to, a mower or mower-conditioner. The types of crops harvested vary widely from short crops that are compliant and flexible to tall crops that are relatively ridged and inflexible. As a general rule however, taller crops are typically more stiff/rigid than short crops so as to stand steadily on the ground. For some crops, it may be preferred for the cutter implement to cut the crop when the crop has a slight lean forward relative to the direction of travel of the cutter implement. <CIT> discloses an implement with a curtain.

According to an aspect of the present disclosure, a cutter implement for cutting crop material is provided. The cutter implement may include a housing, a cutter, and a curtain. The housing has a forward end for engaging the crop material when moving in a direction of operation. The housing at least partially defines a cutting region disposed at the forward end. The cutter is coupled to the housing and can cut the crop material in the cutting region. The curtain is coupled to the forward end of the housing and is positioned forward of the cutter relative to the direction of operation for engaging and leaning the crop material upstream of the cutter. The curtain includes a stiffness control feature operable to control a vertical stiffness of the curtain to provide a variable vertical stiffness that increases with an increase in a bend angle of the curtain rearward relative to the direction of operation.

A curtain apparatus for a cutter implement is provided. The curtain apparatus includes a curtain operable to be coupled to the cutter implement. The curtain includes a stiffness control feature operable to control a vertical stiffness of the curtain to provide a variable vertical stiffness that increases with an increase in a bend angle of the curtain rearward relative to a direction of operation.

Referring to <FIG>, a cutter implement <NUM> include a cutter <NUM> extending in a forward direction relative to the direction of the operation V, which is the travel direction. For clarity, a housing <NUM> of the cutter implement <NUM> is omitted in <FIG> but is shown in <FIG> and <FIG>. A cutting region <NUM> is defined in front of the cutter <NUM>. Optionally, a crop processor <NUM> is positioned rearward of the cutter relative to the direction of operation (travel) and operable to condition cut crop material <NUM>. The crop processor <NUM> in one implementation includes a first conditioning roll <NUM> and a second conditioning roll <NUM> engaging with each other to condition the crop material <NUM>. However, it should be appreciated that the crop processor <NUM> may be implemented in another configuration not shown or described herein that is capable of processing cut crop as understood by those skilled in the art. The cutter implement <NUM> may include, but is not limited to, a mower and a mower-conditioner. The mower and/or mower conditioner may be drawn by a vehicle, such as but not limited to a tractor or other similar vehicle, or may be a self-propelled implement having motive power, steering systems, control systems, etc..

Leaning the crop <NUM> forward may provide several benefits for crop cutting and crop conditioning process. For example, it may allow the base end of the stems to be fed into the first conditioning roll <NUM> and the second conditioning roll <NUM> as shown in <FIG>. Feeding the crop (material) <NUM> into the crop processor <NUM> in this manner has shown to improve cutting performance by minimizing re-cutting at the cutter <NUM> and it improves cut height uniformity. However, the degree to which the crops <NUM> are flexed forward greatly affects how much the performance can be improved. In fact, if the crop <NUM> is over-flexed it may hinder cutting performance.

Therefore, to achieve the improvement in cutting and conditioning performance, the crop <NUM> may be flexed forward "slightly" so that the stem remains intact and erect but not "over-bent" such that the stem is kinked/yielded, causing the crop to permanently tip or lay on the ground prior to being severed. In general, taller crops are typically more stiff/rigid than short crops. Therefore, a bending force required to bend rigid taller crops forward may need to be stronger than the bending force required to bend shorter more compliant crops forward. The present disclosure includes a cutter implement and a cutter apparatus, which have a stiffness control feature for a curtain which determines a vertical stiffness of the curtain to determine the force applied to the crop. The vertical stiffness of the curtain is directly related to the resistance against bending of the curtain resulting from the pushing/reaction of the crop material <NUM> acting on the curtain <NUM>. As shown in <FIG> and <FIG>, the cutter implement <NUM> may include a housing <NUM>, the cutter <NUM>, and a curtain <NUM>. The housing <NUM> includes an upper frame portion <NUM>, a first lateral frame portion <NUM>, and a second lateral frame portion <NUM>. The first lateral frame portion <NUM> and the second lateral frame portion <NUM> are spaced apart from each other and disposed on opposing lateral sides of the housing <NUM> relative to a central longitudinal axis <NUM> of the housing <NUM>. The housing <NUM> also has a forward end <NUM>, included by the upper frame portion <NUM> in one implementation, for engaging the crop material <NUM> when moving in a direction of operation V. The housing <NUM> at least partially defines the cutting region <NUM> disposed at or near the forward end <NUM>.

The cutter <NUM>, as shown in <FIG> and <FIG>, is coupled to the housing <NUM> and is operable to cut the crop material <NUM> in the cutting region <NUM>. In one implementation, the cutter <NUM> is configured as a cutter-bar extending laterally transverse relative to the central longitudinal axis <NUM> of the housing <NUM>, across a width of the cutter implement <NUM>.

The curtain <NUM> is coupled to the forward end <NUM> of the housing <NUM> and is positioned forward of the cutter <NUM> relative to the direction of operation V for engaging and leaning the crop material <NUM> upstream of the cutter <NUM>, as shown in <FIG> and <FIG>. The curtain <NUM> at least partially defines the cutting region <NUM>. In one implementation, the curtain <NUM> has one section coupled laterally to the forward end <NUM>, as shown in <FIG>. In another implementation, the curtain <NUM> may include multiple sections coupled laterally to the forward end <NUM>. As shown in <FIG> and <FIG>, the curtain <NUM> may include three sections <NUM>, <NUM>, <NUM>. The middle section <NUM> has an offset to the other two adjacent sections <NUM> and <NUM> in the direction of operation V. The number of the section(s) is only for explanatory purpose, and it can be varied depending on the particular need. The number of the sections being equal to or more than two may allow the operator to replace part of the curtain <NUM> section by section. The implementations of the curtain <NUM> described in this disclosure may be applied to single section or more than one section of the curtain <NUM>. The curtain <NUM> is moveable in a rearward direction relative to the direction of operation V. When the cutter implement <NUM> moves in the direction of operation V, the curtain <NUM> contacts the crop <NUM> and may be moved in the rearward direction due to the stiffness of the crop <NUM>. The crop <NUM> may be simultaneously flexed forward due to the force applied from the curtain <NUM>. The weight, material, shape, and/or other characteristic of the curtain <NUM> affect the vertical stiffness of the curtain, and may bias the curtain <NUM> toward its original position, which provides a resistance of the curtain <NUM> against rearward movement after the curtain <NUM> contacts the crop <NUM>.

Referring to <FIG> the curtain <NUM> includes a stiffness control feature <NUM> which determines the vertical stiffness of the curtain <NUM>. The stiffness control feature <NUM> is operable to provide a variable vertical stiffness that increases with an increase in a bend angle θ of the curtain <NUM> rearward relative to the direction of operation V. The vertical stiffness of the curtain <NUM> is directly related to the resistance against bending resulting from the pushing of the crop material <NUM> acting on the curtain <NUM>. <FIG> illustrate the bend angle θ, can be defined at any point at the (section of) curtain <NUM> relative to vertical line(s). The location and the shape of the stiffness control feature <NUM> shown in <FIG> are merely a demonstration. The stiffness control feature <NUM> can be disposed inside or outside the curtain <NUM> or as characteristic(s) of the curtain <NUM> itself, the details of which will be described later. As shown in <FIG>, the vertical line L (L1) overlaps with the reference line LRef of the curtain <NUM>, before the curtain <NUM> contacts the crop material <NUM>. The reference line LRef may be drawn in the middle part of the curtain for showing the extent (e.g. the bend angle θ) the curtain <NUM> bends. The curtain <NUM> is hung vertically relative to a ground surface before the curtain <NUM> engages the crop material <NUM> and exhibits the bend angle θ substantially equal to zero.

With reference to <FIG>, when the curtain <NUM> as a whole is rearward, the bend angle θ between the vertical line L1 and the reference line LRef increases from zero to the bend angle θ1. The intersection P1 of the vertical line L1 and the reference line LRef is at the top of the curtain <NUM>.

With reference to <FIG>, when an upper portion <NUM> of the curtain <NUM> remains in the same position but a lower portion <NUM> of the curtain <NUM> is rearward, the bend angle θ between a vertical line L2 and the reference line LRef increases from zero to the bend angle θ2. The intersection P2 of the vertical line L2 and the reference line LRef is at the bottom of the upper portion <NUM> or the top of the lower portion <NUM> of the curtain <NUM>.

With reference to <FIG>, when the upper portion <NUM> of the curtain <NUM> and a lower portion <NUM> of the curtain <NUM> are rearward in different extents, one bend angle θ between a vertical line L3 and the reference line LRef increases from zero to the bend angle θ3, and another bend angle θ between a vertical line L4 and the reference line LRef increases from zero to the bend angle θ4. The intersection P3 of the vertical line L3 and the reference line LRef is at the top of the upper portion <NUM>. The intersection P4 of the vertical line L4 and the reference line LRef is at the bottom of the upper portion <NUM> or the top of the lower portion <NUM> of the curtain <NUM>. The number of the vertical lines and intersections can be more than two, up to infinite, such as, for example, when the curtain <NUM> at least partially includes a curved shape.

The configuration of the stiffness control feature <NUM> shown in <FIG> is not limited to what it is shown. For example, the stiffness control feature <NUM> may have, alone or in combination, variable thickness, variable durometer, multiple portions coupled to one another with different thickness, multiple layers, multiple layers with multiple strips, and weigh element(s).

<FIG> illustrates the first implementation of a stiffness control feature <NUM>, <NUM>. The stiffness control feature <NUM> includes a thickness of the curtain <NUM>, and the thickness of the curtain <NUM> is variable in a vertical direction. The thickness of the curtain <NUM> increases from a bottom of the curtain <NUM> to a top of the curtain <NUM>, proportionally in this implementation, so as to form a slope on a forward surface <NUM> operable to engage the crop material <NUM>. The rearward surface <NUM>, the opposite surface of the forward surface <NUM>, may be vertical to the ground surface.

Referring to <FIG> illustrates the second implementation of a stiffness control feature <NUM>, <NUM>. The stiffness control feature <NUM> of the curtain <NUM> has variable durometer, the higher portion of the curtain <NUM>, the greater of durometer. For example, an upper portion <NUM> of the curtain <NUM> has greater durometer than does a lower portion <NUM> of the curtain <NUM>. Therefore, the stiffness control feature <NUM> is operable to increase the vertical stiffness of the curtain <NUM> from a bottom of the curtain <NUM> to a top of the curtain <NUM>.

Referring to <FIG> illustrates the third implementation of a stiffness control feature <NUM>, <NUM> of the curtain <NUM> having multiple portions coupled to one another with different thickness. The stiffness control feature <NUM> of curtain <NUM> includes a first portion <NUM>, a second portion <NUM> coupled to a lower part of the first portion <NUM>, and a third portion <NUM> coupled to a lower part of the second portion <NUM>. The curtain <NUM> may be made by one-piece (not shown), with a thickness of the first portion <NUM> is greater than a thickness of the second portion <NUM>, and the thickness of the second portion <NUM> is greater than a thickness of the third portion <NUM>. Alternatively, the stiffness control feature <NUM> may include multiple layers with different height stacking together to form the first portion <NUM>, second portion <NUM>, and the third portion <NUM>.

Referring to <FIG> illustrates the fourth implementation of a stiffness control feature <NUM>, <NUM> of the curtain <NUM> having multiple layers. The number of the layers in the fourth implementation is four but it may be any number of layers. The stiffness control feature <NUM> includes a first layer <NUM>, a second layer <NUM> disposed rearward of the first layer <NUM> relative to the direction of operation V, a third layer <NUM> disposed rearward of the second layer <NUM> relative to the direction of operation V, and a fourth layer <NUM> disposed rearward of the third layer <NUM> relative to the direction of operation V. The first, second, third, fourth layers <NUM>, <NUM>, <NUM>, <NUM> are operable to increase the vertical stiffness of the curtain <NUM> when the curtain <NUM> is in response to the first layer <NUM> moving in the rearward direction and engaging the second layer <NUM>, the second layer <NUM> moving in the rearward direction and engaging the third layer <NUM>, the third layer <NUM> moving in the rearward direction and engaging the fourth layer <NUM>, with an increase of the bend angle θ. The heights of the multiple layers (the first, second, third, fourth layers <NUM>, <NUM>, <NUM>, <NUM> as shown in FGI. <NUM>) may be different. In one implementation, the heights of the layers may decrease from the first layer <NUM> to the fourth layers <NUM>. For instance, the height of the first layer <NUM> is longer than a height of the second layer <NUM>. The rearward layers such as the third layer <NUM> and the fourth layer <NUM> will only bend when the curtain <NUM> leans high crop material (usually stiffer than short crop material) forward. The thickness of the multiple layers (the first, second, third, fourth layers <NUM>, <NUM>, <NUM>, <NUM> as shown in FGI. <NUM>) may be different. In one implementation, the thickness of the layers increases from the first layer <NUM> to the fourth layer <NUM>. For instance, a thickness of the second layer <NUM> is greater than a thickness of the first layer <NUM>. With forward layer longer and thinner than rearward layer, such arrangement may provide more consistent vertical stiffness increase with the increasing bend angle θ, so as to provide more consistent increasing force to lean the crop material <NUM> forward. However the present disclosure also includes an implementation that may have forward layers shorter and/or thicker than rearward layers, or any other variation.

The distances between the layers may be different. In one implementation, the distance between layers may increase. For instance, a distance between the second layer <NUM> and the third layer <NUM> is greater than a distance between the first layer <NUM> and the second layer <NUM>. In that arrangement, the time the first layer <NUM> gets influenced by the second layer <NUM> is shorter than the time the first layer <NUM> and second layer <NUM> get influenced by the third layer <NUM>, and the stiffness of the curtain <NUM> changes in different extent during the course of bending partially determined by the distance between layers. Spacing the multiple layers (the first, second, third, fourth layers <NUM>, <NUM>, <NUM>, <NUM> as shown in FGI. <NUM>) apart could also influence their vertical stiffness. It is noted that when the multiple layers closer together the stiffer they are. The operator may change the distances between any two of the adjacent layers depending on the needs.

<FIG> illustrates the fifth implementation of a stiffness control feature <NUM>, <NUM> of the curtain <NUM> having multiple layers, each of which include multiple strips. The number of the layers in the fifth implementation is three but it may be any other multiple number. The stiffness control feature <NUM> includes a first layer <NUM>, a second layer <NUM> disposed rearward of the first layer <NUM> relative to the direction of operation V, and a third layer <NUM> disposed rearward of the second layer <NUM> relative to the direction of operation V. The first, second and third layers <NUM>, <NUM>, <NUM> may increase the vertical stiffness of the curtain <NUM> when the curtain <NUM> is in response to the first layer <NUM> moving in the rearward direction and engaging the second layer <NUM> and the second layer <NUM> moving in the rearward direction and engaging the third layer <NUM>, with an increase of the bend angle θ. As shown in <FIG>, the thickness of the layers increase from the first layer <NUM> to the third layer <NUM>. The first layer <NUM> includes a row of first strips <NUM> disposed laterally relative to a central longitudinal axis <NUM> of the housing <NUM>, the second layer <NUM> includes a row of second strips <NUM> disposed laterally relative to the central longitudinal axis <NUM> of the housing <NUM>, and the third layer <NUM> includes a row of third strips <NUM> disposed laterally relative to the central longitudinal axis <NUM> of the housing <NUM>. Each respective one of the first strips <NUM> has a first width, each respective one of the second strips <NUM> has a second width, and each respective one of the third strips <NUM> has a third width. The first width is greater than the second width and the second width is greater than the third width. The at least one of the second strips <NUM> is operable to overlap two adjacent first strips <NUM> so as to cover a space between the two adjacent first strips <NUM> in the lateral direction.

<FIG> illustrates the sixth implementation of a stiffness control feature <NUM>, <NUM>. The stiffness control feature <NUM>, <NUM> of the curtain <NUM> includes weight elements <NUM> attached to the curtain <NUM>. As shown in <FIG>, the curtain <NUM> has three sections in this implementation and therefore an offset of the curtain in the direction of operation V is shown in <FIG>. The weight elements <NUM> are operable to at least partially change the stiffness of the curtain <NUM> and to increase the resistance against bending of the curtain <NUM> when the curtain <NUM> engages crop material <NUM>. It is noted that the weight elements <NUM> can be arranged on the forward or rearward surface, or both. The location of the weight elements <NUM> can be determined depending on the needs. The weight elements <NUM> attach to the curtain <NUM> via fasteners such as screw, nuts and bolt, or adhesive agent. Changing the weight elements <NUM> on a segment of the curtain <NUM> can be performed by replacing them with another weight of weight elements <NUM> or replacing the section they attached to with another segment of the curtain <NUM> having different weight elements <NUM> (different from the number, weight, and locations, for example.

<FIG> is a schematic perspective view of a cutter implement <NUM> having seven sections with respective stiffness control features <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>. The order and number of the segments with different stiffness control features <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> can be changed depending on the needs.

The present disclosure curtain apparatus having the curtain <NUM> for a cutter implement <NUM>. The curtain <NUM> may include one or multiple sections. The curtain <NUM> may include one or more stiffness control feature <NUM> (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) as described previously.

Claim 1:
A cutter implement (<NUM>) for cutting crop material (<NUM>), the cutter implement (<NUM>) comprising:
a housing (<NUM>) having a forward end (<NUM>) for engaging the crop material (<NUM>) when moving in a direction of operation (V), wherein the housing (<NUM>) at least partially defines a cutting region (<NUM>) disposed at the forward end (<NUM>) thereof;
a cutter (<NUM>) coupled to the housing (<NUM>) and operable to cut the crop material (<NUM>) in the cutting region (<NUM>);
a curtain (<NUM>) coupled to the forward end (<NUM>) of the housing (<NUM>) and positioned forward of the cutter (<NUM>) relative to the direction of operation for engaging and leaning the crop material (<NUM>) upstream of the cutter (<NUM>), characterized in that, the curtain (<NUM>) includes a stiffness control feature (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) which determines a vertical stiffness of the curtain (<NUM>) to provide a variable vertical stiffness that increases with an increase in a bend angle of the curtain (<NUM>) rearward relative to the direction of operation (V).