referring to fig1 an exemplary crop or plant material 100 is shown prior to the harvesting of any particular component thereof . the crop or plant material 100 which is to be harvested may include , for example , wheat , barley or corn . it is noted however , that the invention is not limited to such specific crops but , rather , may be utilized in connection with various types of grain crops , cereal crops and legumes . the plant material 100 depicted in fig1 is representative of a grain crop and comprises a grain material 101 housed within , or covered by , chaff material 102 . the plant material 100 further includes a stem 104 ( the culm , referred to as straw ) having nodes 106 formed therein dividing the stem into internodal sections 104 a - 104 d . the stem 104 may be wrapped , or at least partially wrapped , by a sheath 108 having one or more leaves 110 branching off therefrom . while the grain 101 is the component that is conventionally harvested from the plant material 100 , other components of the plant material 100 also exhibit desirable qualities and may be useful if they are able to be adequately separated and harvested . for example , the sheaths 108 and leaves 110 conventionally exhibit a higher concentration of nutrients and minerals than do other parts of the plant 100 . sheaths 108 and leaves 110 , therefore , may be utilized to enrich the soil for future crops . also , the stem 104 of various types of plant material 100 is rich in cellulose . this cellulose may be extracted for various revenue generating purposes . for example , the cellulose may be used in extruded plastics , or in production of ethanol for use as a renewable energy source . however , efficient extraction of cellulose from the stem 104 requires selective harvesting of the stem 104 from the sheath 108 , leaves 110 and other components . further , extraction of cellulose from the stem 104 becomes easier if the stem is broken apart and separated from the nodes 106 . thus , for efficient extraction of plant cellulose , it becomes desirable to selectively harvest the internodal stem sections 104 a - 104 d separate from the other components . it is additionally noted that , particularly with small grain material , when selectively harvesting a plant component , such as the internodal stems 104 a - 104 d , it is desirable to perform the harvest prior to discharging the specific plant component back to the crop field as it is generally inefficient to try and recapture the specific plant component from the ground during a second pass across the field . referring now to fig2 a harvesting machine 120 is shown according to one embodiment of the present invention . the harvesting machine 120 includes a chassis 122 supporting an operator &# 39 ; s platform 124 and cab 126 from which an operator controls a plurality of other components housed within and / or supported by the chassis 122 which shall be described in more detail below . the harvesting machine also includes a power source 128 , such as an internal combustion engine , to propel the harvesting machine 120 as well as provide power to the various components and mechanisms thereof . in operation , a header 130 located at the forward end of the harvesting machine 120 cuts down a standing crop , or picks up a previously cut crop , of plant material 100 ( see fig1 ) as the harvesting machine 120 is propelled across a crop field . a conveying mechanism within the header 130 , such as an auger 132 , conveys the cut crop transversely across the header 130 to a second conveying mechanism 134 such as , for example , a feeder . the second conveying mechanism 134 transports the cut crop to a primary threshing and separating mechanism 136 . the primary threshing and separating mechanism shown in fig2 includes an longitudinally oriented rotor 138 and cooperatively configured and positioned concave 140 which , while not shown in fig2 may wrap partially around the rotor . the concave 140 may be formed as a grate or a relatively coarse sieve such that the grain material may flow therethrough as the crop is subjected to a rubbing action between the rotor 138 and the concave 140 . in operation , the harvesting machine 120 may include at least two such threshing and separating mechanisms 136 set in a side - by - side orientation . it is noted that while the harvesting machine 120 is shown and described to include a longitudinal rotor primary threshing and separating mechanism 136 , other conventional mechanisms , such as , for example , transversely oriented threshing and separating mechanisms , may also be utilized in conjunction with the present invention as will be appreciated by those of ordinary skill in the art . as the crop is processed through the threshing and separating mechanism 136 , grain falls through the concave 140 and onto a grain pan 142 which may , for example , be coupled with a vibrating energy source for conveyance of the grain along the grain pan 142 toward the aft end of the harvesting machine 120 . the plant material not falling through the concave 140 is conveyed to a beater 144 positioned above and within a grate 146 for further separation of the grain . grain falling through the grate 146 , as well as grain transported rearward by the grain pan 142 , is then sifted through one or more sieves 148 and 150 for additional cleaning and separation of the grain . in conjunction with the sieves 148 and 150 , an air source , such as but not limited to a forced air source 190 , as depicted in fig2 - 4 , including at least one fan or other means for generating a source of forced air directabable by baffles , conduits or other guides that may be used to direct forced air upwards through the sieves 148 and 150 to further remove chaff and other impurities that may be intermixed with the grain . such chaff and other relatively light impurities are conveyed rearward to be discharged from the harvesting machine 120 while the grain passes through the sieves 148 and 150 into a grain collection zone 152 . a conveying mechanism 154 , such as an auger , conveys the grain laterally to yet another conveying mechanism 156 , such as a grain elevator , which discharges the grain into a central storage vessel 158 . while the grain is discharged through the concaves 140 and the grate 146 , the straw is discharged from the beater 144 to a straw conveyor 160 such as , for example a straw walker , as will be appreciated by those of skill in the art . the straw conveyor 160 transports the straw , which largely comprises the stems of the harvested crop material , to a secondary threshing and separating mechanism 162 . the straw conveyor 160 may also be configured as another sieve so as to provide additional separation of the crop material passing therealong . the secondary threshing and separating mechanism 162 may include a rotor 164 and concave 166 as did the primary threshing and separating mechanism 136 . however , the secondary threshing and separating mechanism 162 may include different design features than the primary threshing and separating mechanism 136 . for example , if both primary and secondary threshing and separating mechanisms 136 and 162 are designed as longitudinally disposed rotors with mating concaves such as shown , the rotor 164 and concave 166 of the secondary threshing and separating mechanism 162 may be designed to be smaller , in length and / or diameter than the rotor 138 and concave 140 of the primary threshing and separating mechanism 136 . further , the secondary threshing and separating mechanism 162 may be designed to be more aggressive than the primary threshing and separating mechanism 136 in that the tines or other rubbing components positioned thereon may exhibit different spacing or configuration than those of the primary rotor 138 . similarly , the concave 166 of the secondary threshing and separating mechanism 162 may exhibit a different grating arrangement , such as the size of openings therein , with respect to the concave 140 of the primary threshing and separating mechanism 136 . the difference in aggressiveness between the primary threshing and separating mechanism 136 to the secondary separating and threshing mechanism 162 is based , at least in part , on which plant components are to be harvested by each . for example , as previously discussed , the primary threshing and separating mechanism 136 is designed to separate and harvest the grain material , while the secondary separating and threshing mechanism is configured to harvest a separate component of the crop material , such as , for example the stems , or more particularly the internodal stems ( i . e ., 104 a - 104 d shown in fig1 ). thus , after separating grain from the crop material , the secondary threshing and separating mechanism 162 , when used to harvest the internodal stems , serves to break the stems of the crop material at locations proximate the nodes 106 ( fig1 ) and then discard the nodes and other impurities through the secondary concave 166 while retaining the internodal stems 104 a - 104 d . a secondary beater 168 with an associated grate 170 may be used to further separate the stems from the nodes . a sieve 172 ( or plurality of sieves ) may be positioned to receive the discharged material from the secondary beater 168 and grate 170 ( or alternatively , if a secondary beater 168 is not used , directly from the secondary threshing and separating mechanism 162 ) for further cleaning and separation . the sieve ( s ) 172 may be combined with a forced air source , as previously described with respect to sieves 148 and 150 , to help separate the plant component being harvested from the undesired components . thus , in harvesting internodal stems , the nodes and other components ( e . g ., remaining chaff , sheaths and / or leaves ) may pass through the sieve 172 for combination with the undesired material previously separated from the grain , the combined stream of undesired or non - harvested plant components being discharged through an outlet port 174 back to crop field . it is noted that , while not shown , the harvesting machine 120 may also include a system or mechanism associated with “ rethreshing ” the plant material as will be appreciated by those of ordinary skill in the art . it is further noted that such rethreshing systems and mechanisms are not to be confused with the secondary threshing and separating mechanism 162 disclosed herein . particularly , as noted above , rethreshing systems are designed to collect and process an amount of crop material discharged from the primary threshing and separating mechanism in an attempt to obtain an additional amount of grain therefrom . in contradistinction , the secondary threshing and separating mechanism disclosed herein is directed to selectively harvesting another component ( i . e ., other than grain ) from the plant material of the crop . upon discharge from the secondary threshing and separating mechanism 162 and / or secondary beater 168 , the harvested plant component ( e . g ., the internodal stems ) may be conveyed to a packaging mechanism 176 . the packaging mechanism 176 may be configured to consolidate and package the harvested plant components into a bale or other similar package that is conveyed through a discharge port or chute 178 . the packaged plant component material may be discharged to the crop field for subsequent collection , or alternatively , discharged to a storage vehicle , such as a trailer being mechanically coupled to and pulled behind the harvesting machine 120 , or a truck driven alongside the harvesting machine 120 . as shown in fig3 which depicts a harvesting machine 120 ′ according to another embodiment of the present invention , the harvesting machine 120 ′ need not have a packaging mechanism integrally associated therewith . rather , a second vehicle 180 housing a packaging mechanism 176 ′ may be mechanically coupled with and pulled behind the harvesting machine 120 ′. in such a case , the component being harvested may be discharged from the harvesting machine 120 ′ after passing through the secondary threshing and separating mechanism 162 and / or the secondary beater 168 . the selectively harvested plant component is then collected by the second vehicle 180 and packaged accordingly . in yet another embodiment of the present invention , shown in fig4 as harvesting machine 120 ″, the secondary threshing and separating mechanism 162 ′ may be housed in a second vehicle 180 ′. thus , after passing through the primary threshing and separating mechanism 136 of the harvesting machine 120 ″, the portion of the crop containing the desired components for additional harvesting ( e . g . the straw / stems ) may be discharged from the harvesting machine 120 ″ to the second vehicle 180 ′ for processing via the secondary threshing and separating mechanism 162 ′. the second vehicle 180 ′ may further include a packaging mechanism 176 ′ for consolidating and packaging the harvested material prior to discharge from the second vehicle 180 ′. additionally , the second vehicle may include an outlet port 174 ′ for discharging undesired plant material ( e . g ., nodes and chaff ) separated out via the secondary threshing and separating mechanism 162 ′. as has been noted above , when selectively harvesting one or more additional components from a given crop such as , for example , the internodal stems , it is often desirable to not discharge the harvested components back to the crop field without proper consolidation and packaging in order to ensure an efficient harvest . thus , if a packaging mechanism is not being utilized , it may be desirable to immediately store the harvested crop , such as in an auxiliary storage tank associated with the harvesting machine 120 or , alternatively , in a storage vehicle pulled by , or driven adjacent to , the harvesting machine 120 . additionally , if the plant component ( other than grain ) being harvested includes the stems , it may be desirable to package the harvested components with material that is biodegradable and / or combustible depending on the intended use of the harvested component material . for example , if the component material is to be used as a combustible energy source , it may be desirable that the packaging material also be combustible such that the component material need not be “ unwrapped ” or “ unpackaged ” before use . such packaging material might include , for example , a web or mesh - type paper - based product that may be wrapped about a mass of the plant component material after consolidation thereof . while the invention may be susceptible to various modifications and alternative forms , specific embodiments have been shown by way of example in the drawings and have been described in detail herein . however , it should be understood that the invention is not intended to be limited to the particular forms disclosed . rather , the invention includes all modifications , equivalents , and alternatives falling within the spirit and scope of the invention as defined by the following appended claims .
a method and apparatus for selectively harvesting multiple components of a plant material . a grain component is separated from the plant material such as by processing the plant material through a primary threshing and separating mechanism . at least one additional component of the plant material is selectively harvested such as by subjecting the plant material to a secondary threshing and separating mechanism . for example , the stems of a plant material may be broken at a location adjacent one or more nodes thereof with the nodes and the internodal stem portions being subsequently separated for harvesting . the at least one additional component may then be consolidated and packaged for subsequent use or processing . the harvesting of the grain and of the at least one additional component may occur within a single harvesting machine , for example , during a single pass over a crop field .