Device for reducing debris accumulation in a rotary cutterhead

A scraper device for connection to the knife connector in a rotary cutterhead and for rotation therewith that prevents debris from accumulating in the space between the knife and the cutterhead housing and which also dislodges accumulated debris from areas adjacent to the space between the knife and the cutterhead housing.

BACKGROUND OF THE INVENTION

This invention relates generally to a machine having a header featuring a plurality of rotary cutters for harvesting crops in a field and, more particularly, to a device for reducing the accumulation of mud and other debris in the rotary cutter such as may be experienced when the machine is operated in wet conditions.

Modern crop harvesting machines having rotary disc cutting headers typically experience significant amounts of dirt, debris, and moisture moving through the header during operation. Operation during wet field conditions generally results in increased debris accumulation rates. One particularly problematic area is the rotary cutter head which is positioned low and forward in the header, adjacent to the ground surface. Furthermore, tight clearances between the rotating cutting bars and the stationary structure can easily become clogged with debris, more so during wet and muddy conditions, which results in diminished crop cutting quality and increases power demands for operating the cutterbar.

It would be desirable to provide an easily installable scraper device that relies on the cutterhead motion to reduce the buildup of debris and contaminants in and on the cutterhead mechanism that would overcome the above problems and limitations.

SUMMARY OF THE INVENTION

Accordingly, the present invention, in any of the embodiments described herein, may provide one or more of the following advantages.

It is an object of one or more embodiments of the present invention to provide a device for reducing debris buildup in a rotary cutterhead.

It is a further object of one or more embodiments of the present invention to provide a device for reducing debris buildup in a rotary cutterhead that may be easily retrofit onto current cutterhead designs.

It is a further object of one or more embodiments of the present invention to provide a device for removing accumulated debris from a rotary cutterhead that functions in connection with operation of the rotary cutterhead.

It is a further object of one or more embodiments of the present invention to provide a device for clearing debris in a space between a stationary portion of a cutterhead module and a rotating knife, the space being provided to allow movement of the knife without contact with the stationary portion, the device connected for rotation with the knife and disposed between the knife and the stationary portion.

It is a still further object of one or more embodiments the present invention to provide a device for maintaining the space between a rotating knife and a stationary portion of a cutterhead free of debris that may otherwise tend to accumulate during operation.

It is a still further object of one or more embodiments of the present invention to provide a device for removing and minimizing debris buildup in a rotary cutterhead that is durable in construction, inexpensive of manufacture, carefree of maintenance, easily assembled, and simple and effective to use.

These and other objects are achieved according to the embodiments of the instant invention described herein by providing a scraper device for connection to the knife connector in a rotary cutterhead and rotation therewith that prevents debris from accumulating in the space between the knife and the cutterhead housing and which also dislodges accumulated debris from areas adjacent to the space between the knife and the cutterhead housing.

DESCRIPTION OF THE PREFERRED EMBODIMENT(S)

Many of the fastening, connection, processes and other means and components utilized in this invention are widely known and used in the field of the invention described, and their exact nature or type is not necessary for an understanding and use of the invention by a person skilled in the art, and they will not therefore be discussed in significant detail. Also, any reference herein to the terms “left” or “right” are used 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. Furthermore, the various components shown or described herein for any specific application of this invention can be varied or altered as anticipated by this invention 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. When referring to the figures, like parts are numbered the same in all of the figures.

First referring toFIG. 1, a partial perspective view of a typical header10for use on an agricultural machine, such as a windrower, used for harvesting a standing crop as the machine travels forwardly across the ground is presented. A modular disc cutterbar15incorporating the principles of the instant invention can best be seen in a configuration in which the disc cutterbar15is disposed along the forward edge of header10for severing crop material from the ground. After cutting, crop material is urged rearwardly and centrally in the header where it may be further processed by the header or deposited on the ground, typically in the form of a windrow. In the instant invention, cutterbar15comprises a plurality of modular rotary cutterheads20laterally spaced apart along the cutterbar15. Rotary cutterheads20are powered by a tractor (not shown) through a driveline (not shown) on the header in a manner that causes all of the plurality of cutterheads to be simultaneously operated. For a more detailed description of a conventional modular disc cutterbar and various configurations thereof, reference is made to U.S. Pat. Nos. 5,996,323, and 5,761,890. The disclosure in those patents are hereby incorporated herein in their entirety by reference.

Modular cutterbar15is formed from alternating cutterhead modules20and spacer modules30. Each cutterhead module20, as best seen inFIG. 2, includes a hollow cast housing22having a shape to retain a low profile and to establish an oil reservoir therewithin. The top of the housing is covered by a rotating head24to which are attached one or more knives26for severing crop from the ground. Cutterhead modules20are gear driven to cause the head24and knives26to be rotated. The cutterhead modules20are assembled in such a manner as to establish a specific timing relationship between adjacent units. More particularly, the cutterhead and spacer modules are arranged such that the knives26on adjacent cutterhead modules20have overlapping cutting paths, but do not come into contact with each other. Failure to maintain this timed relationship during operation will result in the knives26from one unit hitting the knives on adjacent unit(s), damaging the cutterhead modules (and possibly initiating a chain reaction that damages all cutterhead modules on the cutterbar), the drive train of the cutterbar and/or prime mover.

Referring now toFIGS. 2 and 3, it can be seen that each cutterhead module20is provided with a forwardly positioned rock guard40and a skid shoe42that passes beneath the cutterhead module20for engagement with the surface of the ground. The skid shoe42protects the cutterhead module housing22from wear due to contact with the surface of the ground. The rock guard40has a semi-circular configuration and is mounted to the opposing forward portions of the spacer modules30adjacent to the corresponding cutter module20. The rock guard40is formed to correspond to the specific shape of the forward portion of the spacer modules30so that when mounted thereon the rock guard40fits snugly against the spacer module.

As can be seen inFIG. 2, small channel100exists between the stationary structure of the rock guard40and skid shoe42, and the rotating head24. Knives26are connected to the head24for rotation therewith by a fastener means93, typically a bolt94and nut95or functionally equivalent means, and are disposed in the channel100. Channel100has a height101which is greater than the clearance required for knives26to be connected to head24and allowed to rotate. This additional clearance in channel100is provided to allow the knives26to be rotated without contacting the stationary rock guard or skid shoe. Additionally, the clearance101between the rock guard40and the head26is required to permit access to the bottom side of knives26, specifically to access the fastener means (e.g., nut94) for maintenance or knife replacement. Knives26may pivot about fastener means93on axis120during operation to prevent damage to the cutterhead or knife in the event a knife strikes an immovable or heavy movable object during operation. As a result, simply extending the rock guard40to a position that minimizes the clearance in channel100or incorporating a similar fixed structure to close part of the opening of channel100is impractical.

Debris tends to collect in the forward-facing open portions of gap100during operation of the cutterbar, especially when ground conditions are wet. As mud accumulates in the gap and along the forward end of the cutterhead module20, the debris buildup tends to interact with the standing crop before the knives26have an opportunity to cut the crop material which adversely effects crop cutting quality. One object of the present invention is to reduce the tendency of mud to accumulate in gap100and to provide a method of removing accumulated debris from the gap following periods when the cutterhead modules may have been idle.

Now referring toFIGS. 2 through 5, the present invention alleviates debris buildup in gap100by providing a scraper50connected to the fastener means93and positioned between the knife26and the stationary rock guard40. Scraper50fills a portion of the space that is normally open to minimize debris accumulation and to dislodge any debris that may be present in the gap (such as following a period when the rotary cutterheads are not operating). In the embodiment shown, scraper50is a generally planar, elongate member55terminating in generally opposing ends51,52that are allowed to rotate about the pivot axis120established by fastener means93. Other shapes for scraper50are contemplated, including members having circular or elliptical cross sections. In one embodiment, scraper50is symmetrically connected to the connection means93so that the ends51,52are equally displaced from the pivot axis120and the elongate member55will not have a rotational position bias with respect to the cutterhead. In the embodiment shown, fastener means93comprises bolt94which extends through openings in the rotating head24and knives26to pivotally connect the two, and nut95which engages bolt94to retain the assembly in position. Nut95or an equivalent threaded connector is connected to elongate member55in a manner such that member55is retain in position when connection means93is assembled. In one embodiment, nut95is welded to member55, though there are numerous functionally equivalent means to provide the connection.

Once assembled and operated, member55fills a portion of the open space in gap100and thereby reduces the tendency of debris to accumulate in the gap. As the cutter head24rotates, member55will also rotate therewith and effectively fill the gap100. When the cutter head24is idled, the member55may be held in position while the bolt94is removed for maintenance on a knife as the areas laterally adjacent to the knife will remain open and unobstructed.