Abstract:
A self-propelled crop harvester or one of the train of towing vehicle and towed implement for processing harvested crop are equipped with a measuring device for the measurement of components in and/or properties of harvested crop that is conveyed along a path and/or along which the measuring device is moved. The measuring device is an optical spectroscope which operates in the visible wavelength range and/or in the near infrared wavelength range. Measurements made are used to determine the amount of particular organic components contained in the harvested crop, such as carbohydrates, organic substances that can be dissolved in enzymes, oil and raw protein; and to determine the amount of non-organic components contained in the harvested crop, such as minerals, for example sodium and magnesium or water. Further parameters of the harvested crop are also measured including solid matter and raw fiber content, length of fibers, caloric or energy content, digestibility and color.

Description:
The present invention pertains to a measuring device for measuring components in and/or properties of crop material that is conveyed along a path and/or past the measuring device. 
     BACKGROUND OF THE INVENTION 
     In the state of the art (DE 196 48 126 A), harvesting machines that are equipped with devices for measuring the crop throughput, moisture and mass or density are known. The surface moisture of the crop material is measured by an infrared sensor while the layer thickness and density, as well as the moisture of the crop, is measured by microwaves with wavelengths from 1m down to less than approximately 0.5 mm. 
     DE 32 32 746 C describes a harvesting machine, in particular a baler, a self-loading forage box or a combine equipped with a moisture sensor that is provided along the path traveled by the harvested crop as it passes through the machine. 
     However, not all parameters needed for the additional usage of the crop material are obtained by these measurements. Of interest for further processing would be, for instance, the protein and/or fat content, digestibility, caloric value, fiber length and content, and so on. 
     U.S. Pat. No. 5,327,708 proposes a system for the investigation of harvested crop. On a combine, a sample is taken at regular time intervals from the flow of the crop reaching the grain tank and is examined by means of an appropriate arrangement for its mass, moisture content and density. Other parameters of the crop such as protein, sugar and oil contents, and color can also be measured. The system limits the detection of values to discrete locations so that a yield ticket would contain a number of gaps. 
     The problem underlying the invention is seen in the fact that a yield ticket specific to a partial area of the parameters with the measurement system disclosed in U.S. Pat. No. 5,327,708 contains gaps. A laboratory analysis to produce a yield ticket is very costly due to the large number of samples required to be taken and analyzed in order to leave no gaps. 
     SUMMARY OF THE INVENTION 
     According to the present invention, a harvesting arrangement is equipped with a measuring system which overcomes the drawbacks of the prior art systems. 
     An object of the invention is to provide a harvesting arrangement equipped with a measuring system which continuously samples crop as the crop travels through the arrangement, or as the arrangement passes over the crop, so as to obtain data from which organic and/or non-organic crop components may be determined. 
     A further object of the invention is to provide a crop harvesting arrangement equipped with a measuring system, that is used in lieu of or in addition to the measuring system defined in the preceding object, which continuously samples crop as it travels through the arrangement, or as the arrangement passes over the crop, so as to obtain data from which the content of solid matter such as raw fiber content, length of fiber, digestibility, the energy content of the harvested crop may be continuously obtained. 
     Yet another object of the invention is to provide a harvesting arrangement equipped with a measuring device, as set forth in the previous objects, wherein the harvesting arrangement is also equipped with a geographical locating system so that the data can be correlated to specific areas of the field from which the crop was harvested. 
     These and other objects will become apparent from a reading of the ensuing description together with the appended drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a schematic left side view of a harvesting machine embodying the present invention. 
     FIG. 2 is a circuit diagram of the on-board computer and various sensors for collecting crop-specific data to be processed by the computer. 
     FIG. 3 is a schematic representation of a device for measuring the content of crop components. 
     FIG. 4 is a schematic representation of the crop component content sensor of the device shown in FIG.  3 . 
     FIG. 5 is a schematic representation of a train of a tractor towing a baler equipped with a crop component content sensor. 
     FIG. 6 is a view like FIG. 5 but showing the tractor equipped with the crop component content sensor. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to FIG. 1, there is shown a harvesting arrangement in the form of a crop harvesting machine  10  here illustrated as a self-propelled forage harvester including a chassis  12  supported by front and rear sets of wheels  14  and  16 , respectively. The operation of the harvesting machine  10  is controlled from a driver&#39;s cabin  18  from which a crop material intake device, that is coupled to the front of the chassis  12 , can be easily seen. By means of the crop material intake device  20 , which is a row-independent corn cutter in this embodiment, material picked up from the ground such as corn, grass or the like, is fed to a chopping drum  22 , which chops it into small pieces and transfers it to a conveyor arrangement  24 . The crop leaves the harvesting machine  10  to an accompanying trailer (not shown) through a discharge duct or spout  26 , which is mounted for swiveling about an upright axis. Between the chopping drum  22  and the conveyor device  24 , there extends a kernel processor  28  through which the conveyed material is tangentially fed to the conveyor device  24 . Additional details of the harvesting machine  10  require no description as it is conventionally known. 
     On the harvesting machine  10  shown in FIG. 1, several sensors are provided for the measurement of the flow of crop material passing through the harvesting machine  10  per unit time, the so-called throughput. A first throughput sensor  29  measures the spacing between two pre-compression rolls  30 , that are arranged between crop material intake unit  20  and the chopping drum  22 , and between which the harvested crop is conveyed. The sensor  29  is in the form of a sliding or rotary resistor (potentiometer) that is coupled for being actuated by the upper roll  30 , which is commonly resiliently suspended for rising and falling motion in response to variations in the thickness and density of the conveyed crop passing between the rolls  30 . Additionally, the rotational speed of one of the pre-compression rolls  30  is measured by means of a second sensor  32 . Beyond that, additional sensors may measure the propulsion torque of the conveyor arrangement  24  and the regrinding arrangement  28 . 
     An on-board computer  40  connected to a display  36  serves to record and evaluate the measured data. 
     A sensor in the form of a light barrier  34  is arranged in the discharge duct  26  to determine whether any harvested crop material is being conveyed through the harvesting machine  10 . Acquisition of measured data takes place only if the light barrier  34  detects a conveyance of crop material. The volume of crop flow, that is the rate at which crop flows through the harvesting machine  10  per unit time, can be calculated by the spacing of the pre-compression rolls  30  and their rotations per minute or rotational speed. Due to the compression by the pre-compression rolls  30 , an approximately constant density of the harvested crop is achieved. Under this presupposition, the volume flow is directly proportional to the mass flow. The light barrier  34  provides information as to whether crop material is present in the discharge duct  26 . All the measurement signals can be triggered with this information. A measurement thus takes place only if the light barrier  34  detects material. The light barrier  34  additionally allows a correction function because, in case of very low crop material flow, it is possible that the movably mounted pre-compression roll  30  might not have undergone an upward excursion, but crop material is nonetheless present. This state of affairs is recognized from the signal of the light barrier  34 , and the crop material flow can be corrected utilizing a constant corrective factor or summation. 
     In addition, in order to calculate a yield, information on the actual vehicle speed and working width are also needed. The vehicle speed can be obtained from data of the propulsion units of the harvesting machine  10  or acquired by a radar sensor  38 . By means of a global positioning system (GPS) sensor  42 , the yield of a specific area in the field can be ticketed or plotted by the on-board computer  40 . 
     The harvesting machine  10  is additionally equipped with a moisture measuring device  44  for measuring the moisture of the crop material. This can be accomplished in a conventional manner, for instance, by conductivity measurement, dielectrically or capacitatively, with microwaves, or optically in the near infrared range. These measuring processes are conventionally known and require no further explanation. 
     According to the invention, a measuring device  46  is provided for the measurement of the contents of certain components of the harvested crop. The measurement processes of the measuring device  46  is preferably optical spectroscopy in the visible wavelength region and/or in the near infrared region. The wavelengths employed lie between 100 nm and 1 mm, preferably between 400 nm and 1.7 μm. In this wave length range, the organic components, in particular, can be detected particularly well. As a rule, here a calibration of the optically operating measuring device  46  will be appropriate. The signal from the light barrier  34  is used for triggering or activating the measuring device  46 . Thereby, water, raw protein, fat, and other contents of the crop material can be displayed on and stored in a geographically referenced form in the on-board computer  40 . The measuring device  46  is also set up to detect additional parameters of the crop material, namely fiber length, fiber content and content of solid dry matter. 
     Reproduced in FIG. 2 is a schematic circuit diagram that shows the connection, by way of a data bus  50 , between the on-board computer  40  and the throughput sensor  29 , the moisture-measuring device  44  for measurement of the moisture content of the harvested crop, and the crop component content measuring device  46 . The data bus  50  obviates the need to lay separate cables, and can also be connected to additional devices of the harvesting machine  10  such as the engine and the operating units as indicated by the small rectangles  47  at either end of the bus  50 . If the data bus  50  is used only for the measuring device, it must be blocked at both ends by blocking resistors. The drawing schematically illustrates that the on-board computer  40  is supplied with a signal from the throughput sensor  34  that is proportional to the mass flow, a signal from the moisture measuring device  44  that contains information about the water content of the harvested crop, and a signal from the measuring device  46  that provides the content of certain components of the harvested crop, such as protein or fat. This information is continuously displayed and stored in memory. 
     A measuring device  46  is presented in FIG.  3 . It comprises a lamp  52  which is arranged inside a lamp housing  54 , and whose broad band (white) light reaches the interior of the discharge duct  26  through which the harvested crop  62  flows. Light reflected by the harvested crop  62  flowing through the duct  26  reaches a sensor  56 , whose detailed structure can be seen in FIG.  4 . 
     The sensor  56  has a housing  60 , in the interior of which is arranged a parabolic mirror  58  featuring a surface having projections of triangular cross section. The projections extend perpendicular to the plane of the drawing. The parabolic mirror  58  scatters the broad band light  64  reflected from the harvested crop  62  in directions dependent on wave length by means of constructive or destructive interference, since the projections are dimensioned relatively small, although represented in exaggeratedly large dimensions in the drawing. The result is two light beams or rays  66  and  68 , respectively comprising a different wavelength range, are reflected from the mirror  58  so as to be deflected to the left and to the right, as seen in FIG.  4 . The light beams  66  and  68  reach their respective detectors  70  and  72 . The detectors  70  and  72  include several light sensitive elements, such as semiconductor detectors, in particular, CCDs, or photo diodes of silicon (Si) or indium-gallium-arsenide (InGaAS) arranged one alongside the other. Therefore, the output signal of each element of the detectors  70  and  72  corresponds to the received intensity in a given light wavelength range, which is defined by the position of the element of detectors  70  and  72  and the diffraction direction of the mirror  58 . Based on the output signals of the elements of the detectors  70  and  72 , an evaluation of the spectra measured can be performed by a computer assigned to the measuring device  46  or with the on-board computer  40 , on the basis of which the determination of the proportions of certain crop components is possible. Near infrared and visible light, e.g., the range from 400 nm to 1700 nm, can be considered as the wavelength range. 
     It would be conceivable, in place of the mirror  58  equipped with the grating, to use only wavelength dependent scattering of the light of a least one prism, that resolves the light spectrally by its dispersion. 
     It should be noted that any measuring device  46  that operates in the visible and/or the infrared wavelength range or region can be used. Hence, in place of the mirror  58  with a grid, as shown, or of prisms, there could be filters arranged to freely rotate on a disk, for example, as are disclosed in EP 511184 A and the references cited therein. 
     FIG. 5 shows a measuring device  46  arranged between a tractor  80  and a baler  82  coupled to it. The baler  82  is provided with a crop intake arrangement  88  in the form of a pick-up and shapes crop that is taken up, in particular grass, into a bale  84 . The measuring device  46  is arranged on the tow-bar  86  between the tractor  80  and the baler  82  on a skid  94 , that slides over the harvested crop deposited in a swath or windrow  90 . Thereby the measuring device  46  is arranged immediately above the swath  90  of harvested crop and can detect its characteristics without any problem. 
     In FIG. 6, the measuring device  46  is fastened to a suspension  92  secured to and projecting forwardly from the font of the tractor  80 . In a manner similar to that described above, the measuring device  46  is carried by the skid  94  which is positioned for sliding over the harvested crop deposited in the swath or windrow  90 .