BACKGROUND OF THE INVENTION

A. Technical Field

The present invention generally relates to a threshing concave for an agricultural combine. More particularly, the invention disclosed herein relates to a universal threshing concave design, which could be used for harvesting different types of crops. Further, using this threshing concave design, the agriculture combine system could be able to release more grains, reduce the amount of damage and accelerate the cleaning process.

B. Description of Related Art

A modern combine harvester, or simply combine, is a versatile machine designed to efficiently harvest a variety of grain crops. The name derives from its combining three separate harvesting operations such as, reaping, threshing, and windrowing into a single process. Among the crops harvested with a combine are wheat, oats, rye, barley, maize or corn, sorghum, soybeans, flax, sunflowers and canola. The separated straw, left lying on the field, comprises the stems and any remaining leaves of the crop with limited nutrients left in it. The straw is then either chopped, spread on the field and ploughed back in, or baled for bedding and limited-feed for livestock. Combine harvesters are one of the most economically important labor-saving machines, significantly reducing the fraction of the population engaged in agriculture.

Despite great advances in mechanics and computer control, the basic operation of the combine harvester has remained unchanged almost since it was invented.FIG. 1depicts an example of an existing combine harvester1. Rotary combines have a rotary crop processing unit2that threshes and separates the grain from the harvested crop material. The rotary crop processing unit is formed by a rotor radially surrounded by a casing. The rotor and casing together define an inlet section, a threshing section and a separating section. In many combine harvester designs, the bottom of the casing has a concave under the threshing section for threshing the crop material and a separating grate under the separator section for separating the grain from the threshed crop material. The inlet3section pulls the harvested crop material from a front crop gathering unit into the threshing section4. The threshing section4threshes the crop material and then feeds the threshed crop material to the separator section.

Within the threshing section4, there is typically a threshing rotor5that tumbles the cut crops to break and shake the grains away from their stalks. One or more concaves6are typically positioned below and work in conjunction with the threshing rotor5.FIG. 1shows three concaves. Generally, each concave6is provided with a combination of threshing elements in the form of straight bars square in cross-section that are spaced apart from one another with wires between the bars. The objective of the bars and wires is to restrict the flow of crop material so as to enhance threshing of the crop material in the threshing section. However, for harvesting corn crops, a tendency frequently develops for crop material flow to be restricted too much by corn shucks getting hung up on the bars and catching on the wires, resulting in clogging of the concave. One solution of the prior art is to change the threshing elements of the concave to round bars with no wires. In some previous inventions, the concave with an array of longitudinal notched and spaced apart threshing elements is disclosed. However, a tendency frequently develops under some crop conditions, other than corn, for too little restriction of crop material flow such that the other crop materials are not threshed effectively, resulting in overloading of the separator section.

From the concave, the crop enters a collection tank7via augers8. The chaff (unwanted material) passes thru the rotor to the discharge beater or chopper toward the rear of machine1. When the collection tank7is full, a collection vehicle pulls alongside the combine. The grain is carried up from the tank by an elevator and shoots out of a side pipe9(sometimes called the unloader) into the collection vehicle. The unwanted chaff tumbles from the back of the machine1. Some combines have a rotating spreader mechanism that throws the straw over a wide area. Often the straw is baled up by a baling machine and used for animal bedding.

In the light of above-mentioned issues, there exists a need for a universal threshing concave design for an agricultural combine, which could be used for harvesting different types of crops. Further, there is a need for a threshing concave that could be able to release more grains, reduces grain damage and accelerates the following cleaning process.

SUMMARY OF THE INVENTION

This summary is provided to introduce a selection of concepts in a simplified form that are further disclosed in the detailed description of the invention. This summary is not intended to identify key or essential inventive concepts of the claimed subject matter, nor it is intended for determining the scope of the claimed subject matter.

The present invention discloses a threshing concave for an agricultural combine. According to the present invention, the threshing concave for an agricultural combine, comprises a frame. The frame includes a pair of opposite side members, and a pair of opposite end members. The side members and the end members join together to make a rectangular frame. Each opposite end member comprises an upper portion with a top edge thereon. In addition, the opposite end members include a plurality of hexagonal shaped openings formed in said upper portion of said each opposite end member adjacent to and below said top edge.

In one aspect of the present invention, the frame further comprises an array of elongated threshing bars. Each threshing bar is positioned at an angle to both the side members and each other threshing bar such that the threshing bars are not parallel to each other. Each bar is seated in a respective one of said openings in said opposite end members of said frame.

In one aspect, each bar comprises a lower portion, an upper portion and a notch. In one aspect, the lower portion of said each bar has substantially a half or semi-hexagonal configuration in cross-section. The upper portion of said each bar has substantially a quarter hexagonal configuration in cross-section. Further, the bar includes a notch defining an aggressive threshing edge recessed into said bar, which is adjacent to said upper portion of said bar and above said lower portion of said bar. In one aspect, the notch is longitudinally extending between said opposite ends of said bar such that, each of said notches is disposed adjacent to said upper portions of said end members of said frame and face opposite to the direction of crop material flow. In one aspect of the present invention, the notch in each bar is defined by a first surface on said lower portion of said bar and a second surface on said upper portion of said bar extending upright from and in transverse relation to said first surface. In some embodiments, the length of the first surface is around 0.25 inch and the length of the second surface is around 0.375 inch.

In one aspect, the frame further includes at least one intermediate member spaced between and extended generally parallel to said opposite end members. The intermediate member is also extended between and joined to said opposite side members. In one aspect, said intermediate member also comprises a top edge and a plurality of openings. The openings of the said intermediate member is positioned adjacent to and below said top edge such that said bars are seated in said openings of said intermediate member.

In one aspect, the openings are formed in said opposite end and intermediate members such that said notches of said bars seated in said openings are disposed substantially above said top edges of said end and intermediate members. In another aspect, the openings are formed in said opposite end and intermediate members such that said notches of said bars seated in said openings are disposed substantially below said top edges of said end and intermediate members.

In one embodiment, the spacing between said openings of said opposite end members and the spacing between said bars seated in said openings increases and decreases in width from one bar to the next to form a pattern, for example as shown inFIG. 2. In some embodiments, the spacing between said openings of said opposite end members ranges from 0.75 inch to 1 inch, thereby allowing the grain to escape at around a 30° angle. In one embodiment, the rear side of the threshing bars is removably attached to a cover plate, to allow air flow out of the said concave.

Other objects, features and advantages of the present invention will become apparent from the following detailed description. It should be understood, however, that the detailed description and the specific examples, while indicating specific embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.

