Patent Publication Number: US-2009233661-A9

Title: Method and apparatus for ascertaining the quantity of a crop harvested in a combine

Description:
The invention relates to a method and an apparatus for ascertaining the quantity of a crop harvested in a combine, as generically defined by the preambles to claims  1  and  13 .  
      From German Patent DE 199 12 372 C1, an apparatus for measuring at least a portion of the grains in the tailings has become known. Along the feeding path taken by the crop being harvested, filtered out by a cleaning system, to a further processing device, there is a sensor that counts only the grains. Upstream of the sensor in the feeding direction of the tailing augur, there is an ear screw in a housing. The housing is equipped, in the region pointing toward the sensor, with adaptable openings through which the grains pass. The signals generated by the sensor are made visible to the driver in the cab on a display.  
      A disadvantage of this embodiment is that the measurement values for the number of grains are shown in the form of absolute values. The measurement values displayed lack the relationship with the throughput, for instance, or other crop streams in the cleaning system.  
      For the driver, it is above all the ratio of the quantity of grains in the tailings to the total quantity of the tailings that is decisive, since this ratio in a simple way reflects the quality of the cleaning system&#39;s performance.  
      It is therefore the object of the invention to refine a method and an apparatus for ascertaining a quantity of a crop harvested in a combine in such a way that the quantity of the crop being harvested is ascertained relatively precisely in a simple way and conclusively displayed.  
      This object is attained according to the invention by the characteristics recited in claims  1  and  13 . Further advantageous embodiments of the subject of the invention will become apparent from the remaining claims.  
      Because the quantity of the crop being harvested in the tailings is represented by means of generating grain stream signals and crop stream signals, the composition of the quantity of the crop being harvested can be displayed. From the composition of the quantity of the crop being harvested, the driver can assess the effectiveness of the cleaning system.  
      Advantageously, the grain stream signals are generated with a grain stream measuring instrument, which includes at least one pulse density sensor, so that the grains contained in the crop stream being harvested in the tailings are detected without first having to separate the grains from the non-grain components.  
      Because the pulse density sensor for measuring the number of grains is a rod sensor, the crop stream being harvested in the combine is unimpeded, and the pulse density attains a magnitude that is usable for further processing.  
      Because the rod sensors are located in the outlet region of the crop being harvested in the tailings leaving the cleaning system, it is assured that the tailings will drop without hindrance in free fall onto the rod sensors, whereupon, because of what is known as structure-borne sound, the grains generate a usable signal in the rod sensors.  
      The rod sensor is secured to the collector and guide pan of the tailing augur by a rubber spring element, so that vibrations while driving, for instance, are transmitted in attenuated form to the rod sensor. Strong unattenuated vibrations can otherwise cause the rod sensor to vibrate, causing grain signals to be tripped without the grains actually striking the rod sensor.  
      The crop stream signal is advantageously generated by a volumetric stream measuring instrument, which measures a volumetric tailings stream in an ear elevator, so that the quantity of the tailings, composed of grains and non-grain components, can be measured continuously.  
      In order that not only the proportion of grain in the crop harvested and the quantity of the tailings but also the grain losses can be determined, the system of the invention may furthermore have a volumetric stream measuring instrument, which generates a grain stream signal that replicates the total quantity of grain harvested.  
      In order for the results of the measurement to be displayed without delay to the driver, the grain stream signals and the crop stream signal are forwarded to an evaluation and display unit. From them, the evaluation and display unit ascertains not only the quantity of grain in the tailings and the quantity of the tailings but also a quantity of grain in the crop being harvested that represents the quantity of harvested grain.  
      If from the grain stream signal, a thousand-grain mass of the type of fruit, and an area equivalent comprising the sensor area and the usable filtration area of the tailing augur, the evaluation and display unit calculates a tailings grain mass, this grain mass can for instance be expressed as a ratio to the mass of the tailings. The value of the mass ratio is displayed in the form of a percentage on a display and serves to assess the effectiveness of the cleaning system.  
      In a comparable way, from the grain stream signal, a thousand-grain mass of the type of fruit, the area equivalent comprising the sensor area and the usable separation area of the tailing augur and a specific density, the evaluation and display unit could calculate a harvested grain volume and set it in proportion to the volumetric tailings stream. The volumetric ratio may likewise be displayed as a percentage on a display and thus also serves to assess the effectiveness of the cleaning system.  
      In a first variant embodiment, the harvested gain quantity and the quantity of the tailings are displayed quantitatively simultaneously in separate displays on a screen of the evaluation and display unit. The driver sees both the absolute values and the ratio of the absolute values to one another. With this display, the driver has the capability of learning when the crop streams in the elevators for instance reach maximum allowable volumetric streams.  
      In an alternative variant embodiment, the harvested gain quantity and the quantity of the tailings are displayed qualitatively on a display on the screen. The evaluation and display unit has already linked the signals with one another, which relieves the driver of this task.  
      A tailings sensing device that generates high-quality tailings signals is obtained if the quantity of the tailings is detected at least in part in a cleaning system associated with the combine, or in a portion of the cleaning system, since in this region the influence of events that adulterate the measurement values is still slight.  
      Especially high-quality signal ascertainment is attained if in this region of the cleaning, the proportion of grain in the tailings is ascertained, since at the transition from the cleaning system to the tailing augur, the grains must travel a relatively long distance counter to the action of gravity, and thus in a simple way, by means of time-tested sensor systems, the number of grains and hence the proportion of grain in the tailings can be detected.  
      A structurally particularly simple embodiment for ascertaining the proportion of grain in the tailings is obtained if at least one grain stream measuring instrument in the region of the cleaning system is provided, which by means of so-called pulse density sensors generates grain stream signals, which qualitatively and/or quantitatively, in an evaluation and display unit, represent the proportion of grain in the tailings.  
      If the cleaning system has a plurality of screen planes, then in an advantageous refinement of the invention, each screen plane is assigned at least one grain stream measuring instrument. This has the advantage that a more-individual reaction to the filtration characteristics of the individual screen planes can be made, because different settings for the screens of the various screen planes are provided.  
      In an advantageous refinement of the invention, the grain stream signals of the plurality of grain stream measuring instruments are processed and displayed as screen-plane-dependent grain proportions in the evaluation and display unit, so that the operator receives more-accurate information about the filtration characteristic of the individual screen planes. 
    
    
      Further advantageous embodiments are the subject of further dependent claims and will be described below in conjunction with an exemplary embodiment shown in several drawings. Shown are:  
       FIG. 1 , a schematic cross section through a combine having a measuring apparatus according to the invention;  
       FIG. 2 , a screen of the evaluation and display unit;  
       FIG. 3 , a second version of a screen of the evaluation and display unit;  
       FIG. 4 , a detail of  FIG. 1 , with measuring apparatuses of the invention. 
    
    
      The exemplary embodiment of the invention shown in  FIG. 1  involves a self-propelled combine  1 , with a so-called tangential thresher mechanism  8  and downstream of it a hurdle shaker  25  as a filtration device. Below the hurdle shaker  25 , there is a cleaning system  18 , comprising two screens  31 ,  32 , disposed in graduated fashion one above the other, and a blower  33 . However, the invention is expressly not limited to combine types embodied in this way.  
      The mode of operation of a combine  1  of this kind will now be described. The crop being harvested  3  is first picked up by a cutting mechanism  2 , which delivers the crop being harvested  3  to an inclined conveyor  6 . The inclined conveyor  6  transfers the crop being harvested  3  to the threshing devices  9 ,  10 ,  11  in its rear region.  
      At the entrance to the thresher mechanism  8 , there is a pre-accelerator drum  9 , which is followed downstream, in the crop flow direction, by a threshing drum  10 . The pre-accelerator drum  9  and the threshing drum  10  are at least partly sheathed from below by a threshing basket  11 .  
      The crop being harvested  3  emerging from the inclined conveyor  6  is engaged by the pre-accelerator drum  9  and is drawn onward by the threshing drum  10  through the threshing gap  13  formed between the threshing drum  10  and the threshing basket  11 . The threshing drum  10  processes the crop being harvested mechanically at this point, and as a consequence, a grain and chaff mixture  14  is filtered out at the threshing basket  11  and delivered via a preparation pan  17  to the cleaning system  18 , so that the grains  19  can be separated from the non-grain components, that is, from the stem parts  20  and chaff parts  21 .  
      From the thresher mechanism  8 , the crop stream  22 , substantially comprising stems that have been threshed out, then passes via the inverter drum  24 , rotating counterclockwise, reaches the hurdle shaker  25 , which feeds the crop stream  22  into the rear region of the combine  1 . In the process, the grains  19  still located in the crop stream  22  are separated out along with any short straw  20  and chaff  21  that is present, by dropping through the hurdle shaker  25 , which is provided with screen openings  26 , onto a return pan  28 . The return pan  28  transports grains  19 , short straw  20 , and chaff  21  to the preparation pan  17 .  
      The grains  19 , short straw  20  and chaff  21  finally, also via the preparation pan  17 , reach the inside of the cleaning system  18 , in which the grains  19  are separated from the short straw  20  and chaff  21 . This is done in such a way that an air stream is passed through the screen openings  29 ,  30  in the upper screen  31  and the lower screen  32  by means of the blower  33 , and this air stream loosens up the crop being harvested  34 , which is guided via the screens  31 ,  32  into the rear region of the combine  1 , and assures that the specifically lighter-weight chaff and short straw components  20 ,  21  will be separated out, while the heavy grains  19  of crop being harvested drop through the screen openings  29 ,  30 . The screens  31 ,  32  are disposed partly one above the other, so that the crop being harvested is screened to different fineness in two stages; the mesh width of the screens  31 ,  32  is variable. By varying the mesh width and/or the rpm of the blower  33 , the proportion and composition of the quantity of crop being harvested that passes through the screen openings  29 ,  30 , known as the material  37  passed through the screen, and the proportion, known as the overflow  38  from the screen, that is transported over the screen  31 ,  32  can be varied. Moreover, the upper screen  31  is as a rule embodied such that it has greater mesh widths in a rearward region known as the tailings region  36 .  
      Material  37  passed through the screen, which drops through the upper screen  31  in the tailings region  36 , and overflow  38  from the screen at the end of the lower screen  32  both as a rule contain heavier particles, or in other words ears that have not been threshed out. The material  37  passed through the screen along with the overflow  38  from the screen is hereinafter referred to as the tailings  39 . The tailings  39  drop onto an inclined collector pan  40  below the cleaning system  18  and slide into an ear feed screw  41 . The ear feed screw  41  feeds the tailings  39  into an ear elevator  43 , which returns it to the thresher mechanism  8 . The collector pan  40 , ear feed screw  41  and ear elevator  43  together form a tailing augur  46 . In the ear elevator  43 , there is a volumetric stream measuring instrument  42 , known per se, which substantially comprises a light gate  44  that generates a product stream signal Z, which varies as a function of the volumetric tailings stream  45 , being fed, of the tailings  39  and thus forms a measure of the quantity of the tailings  39 .  
      To determine a proportion of grains  35  in the tailings quantity  39 , a grain stream measuring instrument  49  is mounted on the end of the lower screen  32 , in the outlet region  47  of the tailings  39  from the cleaning system  18 , and it includes a plurality of pulse density sensors  50  (see the enlarged detail B). The pulse density sensors  50  are rod sensors  51 , which are known per se and therefore not explained in further detail. The rod sensors  51  generate a grain stream signal Y, which varies in proportion to the detected number of grains  35  in the tailings quantity  39 . Each rod sensor  49  is secured by a rubber spring element  48  to the collector pan  56  of the tailings device  46 . For generating highly precise grain stream signals Y for the stream  39  of the crop being harvested, each screen plane  31 ,  32  may, as shown in  FIG. 4 , be assigned a separate grain stream measuring instrument  49 ; the grain stream signals Y now generated form a measure of the proportion of grain in the tailings filtered out at the upper screen  31  and the total proportion  35  of grain contained in the stream  39  of the crop being harvested. This has the advantage in particular that separate information for the lower and upper screens  31 ,  32  can be made available to the operator of the combine  1 , which enables him to act more precisely on the cleaning losses  53  in such a way that the upper and lower screens  31 ,  32  are given different settings.  
      For the sake of simplicity, see the further description of  FIG. 1 , although the effects to be described also refer to the disposition of a plurality of grain stream measuring instruments  49  as in  FIG. 4 .  
      The overflow  52  from the screen, which does not drop through the upper screen  31 , is ejected in the rear region of the combine  1 ; the grains contained in this overflow  52  from the screen form the cleaning loss  53 . The cleaning loss  53  is detected in a manner known per se with knocking sensors  61 . The cleaning loss signal V generated by the knocking sensors  61  is substantially proportional to the cleaning losses  53 .  
      Both the straw  54  and a certain percentage of lost grains  55  migrate via the hurdle shaker  25  to the rear end of the combine  1 , where they are ejected as filtration loss  57 . The filtration loss  57  is also detected in a manner known per se by knocking sensors  62 . The filtration loss signal A generated by the knocking sensors  62  is substantially proportional to the filtration losses  57 . The grains  19  that have passed through both screens  31 ,  32  of the cleaning system  18  drop onto a further inclined collector and guide pan  56  and slide into a grain feed screw  58 , which delivers the grains  19  to a grain elevator  59 . From the grain elevator  59 , they are then fed into a grain tank  60  of the combine  1 , where they can be reloaded as needed onto a transport cart by a tank emptying conveyor  63 . A volumetric stream measuring instrument  65  known per se is disposed in the grain elevator and substantially comprises a light gate assembly  66 , which measures the volumetric stream of grain  67  being fed. The at least one light gate assembly  66  generates a crop stream signal Z, which varies in proportion to the volumetric stream of grain  67 . It is within the scope of the invention that for improving the crop stream signals Z, more than one light gate  66  may also be provided.  
      The volumetric stream measuring instruments  42 ,  65  and the grain stream measuring instruments  49  as well as the knocking sensors  61 ,  62  are connected to an evaluation and display unit  68 , which is preferably located in the cab  79 . The crop stream signals X, Z generated by the light gates  44 ,  66  and the grain stream signals Y generated by the rod sensors  51 , along with the filtration loss signals A and the cleaning loss signals V are transferred to the evaluation and display unit  68 . With the crop stream signals X, Z, the evaluation and display unit  68  calculates the total quantity of grain harvested as well as the quantity of the tailings  39 ; with the grain stream signal Y, it calculates the proportion  35  of grain harvested; and with the filtration loss signals A and the cleaning loss signals V, it calculates both the cleaning losses  53  and the filtration losses  57 . The number of grains ascertained by the rod sensors  51  is converted in a manner known per se, with an area equivalent comprising the sensor area and the usable filtration area, into an actual number of grains present; the area equivalent is stored in memory in the evaluation and display unit  68 . The evaluation and display unit  68  may furthermore calculate the corresponding mass of grains, using the calculated number of grains and the thousand grain mass for that particular type of fruit, or the grain volume, using the specific density of the grains. In addition, the possibility exists that the evaluation and display unit  68  will calculate mass and/or volume ratios between crop stream quantities or grain quantities. The calculated values are displayed on a screen  69  of the evaluation and display unit  68 ; the quantity of the crop harvested  39  is displayed by means of the generation of grain stream signals Y and crop stream signals Z, X.  
       FIG. 2  shows a first exemplary embodiment of a screen  69  of the evaluation and display unit  68 .  
      The screen  69  has a plurality of displays  70 - 73 , which make information available to the driver about machine settings and operating states of the combine  1 . In a triangular graphical display  70  in the middle, the volumetric tailings stream  45  being conveyed at that moment in the ear elevator  43  is shown, which quantitatively corresponds to the quantity of the tailings  39 . Along the right-hand leg of the triangular display, there is a trapezoidal graphical display  71 , which at the same time quantitatively represents the proportion  35  of grain harvested, measured at that moment, in the quantity of the tailings  39 . To the left and right beside it, there are two further triangular graphical displays  72 ,  73 ; the display  72  on the left shows the filtration loss  57 , and the display  73  on the right shows the cleaning loss  53 . To aid in recognition, symbols  74  through  77  are provided on the displays  70  through  73  and symbolize the parameters displayed.  
       FIG. 3  shows a second exemplary embodiment of a screen  69  of the evaluation and display unit  68 . The screen  69  differs in that between the two outer graphical displays  72 ,  73 , there is only one rectangular graphical display  78 . The rectangular graphical display  78  shows the ratio in percentage at that moment between the mass of the tailings grain quantity  35  and the mass of the tailings quantity  39 . The ratio of these two mass streams is an indicator of the effectiveness of the cleaning system  18  and serves as a substitute for the subjective visual assessment of the quantity of the tailings  39  by the driver. From the combined displays  70  through  73  and  78 , the driver can immediately tell how a change in the rpm of the blower  33  of the cleaning system  18 , for instance, or an adjustment of the mesh width of the screens  31 ,  32 , affects the cleaning action of the cleaning system  18 . If one parameter changes, the driver can feasibly recognize the influence of the adjustment and can optimize the action of the cleaning system  18 .  
      In closing, it will be pointed out once again that the combine shown in the drawings and the measuring apparatus, as well as the concrete method explained in conjunction with them, are solely exemplary embodiments, which can be varied in manifold ways by one skilled in the art without departing from the scope of the invention. For instance, the mass stream of grains in the tailing augur can be set into proportion to other mass streams detected, and the mass streams set in a ratio can be shown on a display. The ratios shown serve to monitor the effectiveness of the operating devices.  
      The masses, quantities and volumes displayed are equivalent to the mass streams, quantity streams and volumetric streams ascertained by the sensors in a defined time interval.  
     LIST OF REFERENCE NUMERALS  
     
         
         
           
               1  Combine  
               2  Cutting mechanism  
               3  Crop being harvested  
               6  Inclined conveyor  
               8  Thresher mechanism  
               9  Pre-accelerator drum  
               10  Threshing drum  
               11  Threshing basket  
               13  Threshing gap  
               14  Grain and chaff mixture  
               17  Preparation pan  
               18  Cleaning system  
               19  Grains  
               20  Stem parts/short straw  
               21  Chaff parts/chaff  
               22  Crop stream  
               24  Inverter drum  
               25  Hurdle shaker  
               26  Screen openings  
               28  Return pan  
               29  Screen openings, upper screen  
               30  Screen openings, lower screen  
               31  Upper screen  
               32  Lower screen  
               33  Blower  
               34  Crop being harvested  
               35  Proportion of grain in the tailings  
               36  Tailings region  
               37  Material passed through the screen  
               38  Screen overflow  
               39  Quantity of tailings  
               40  Collector pan  
               41  Ear feed screw  
               42  Volumetric stream measuring instrument  
               43  Ear elevator  
               44  Light gate  
               45  Volumetric tailings stream  
               46  Tailing augur  
               47  Outlet region  
               48  Rubber spring element  
               49  Grain stream measuring instrument  
               50  Pulse density sensor  
               51  Rod sensor  
               52  Screen overflow  
               53  Cleaning loss  
               54  Straw  
               55  Lost grains  
               56  Collector and guide pan  
               57  Filtration loss  
               58  Grain feed screw  
               59  Grain elevator  
               60  Grain tank  
               61  Knocking sensors  
               62  Knocking sensors  
               63  Grain tank emptying pipe  
               65  Volumetric stream measuring instrument  
               66  Light gate assembly  
               67  Volumetric stream of grain  
               68  Evaluation and display unit  
               69  Screen  
               70  Graphical display  
               71  Graphical display  
               72  Graphical display  
               73  Graphical display  
               74  Symbol  
               75  Symbol  
               76  Symbol  
               77  Symbol  
               78  Graphical display  
               79  Cab  
              A Filtration loss signal  
              V Cleaning loss signal  
              X Grain stream signal  
              Y Grain stream signal  
              Z Crop stream signal