U.S. patent application number 09/168533 was filed with the patent office on 2002-06-20 for device and method for measuring the moisture of crop material in agricultural machines.
Invention is credited to BEHNKE, WILLI, DIEKHANS, NORBERT, KERSTING, ALFONS.
Application Number | 20020073770 09/168533 |
Document ID | / |
Family ID | 22611887 |
Filed Date | 2002-06-20 |
United States Patent
Application |
20020073770 |
Kind Code |
A1 |
DIEKHANS, NORBERT ; et
al. |
June 20, 2002 |
DEVICE AND METHOD FOR MEASURING THE MOISTURE OF CROP MATERIAL IN
AGRICULTURAL MACHINES
Abstract
The invention relates to a moisture measuring device and a
method for measuring moisture of the crop material in harvesting
machines. To improve the moisture measurement, the combination of
the moisture measuring device with a sensor state monitoring device
ensures that the manual calibration effort is reduced. According to
the method disclosed in the present invention, the correction value
from the measured moisture value is at least, in part, a function
of the working condition of the harvesting machine.
Inventors: |
DIEKHANS, NORBERT;
(GUTERSLOTH, DE) ; KERSTING, ALFONS; (OELDE-LETTE,
DE) ; BEHNKE, WILLI; (STEINHAGEN, DE) |
Correspondence
Address: |
ROBERT E MUIR
HUSCH & EPPENBERGER
401 MAIN STREET
STE. 1400
PEORIA
IL
61602
US
|
Family ID: |
22611887 |
Appl. No.: |
09/168533 |
Filed: |
October 8, 1998 |
Current U.S.
Class: |
73/73 |
Current CPC
Class: |
G01N 25/56 20130101;
A01D 41/127 20130101 |
Class at
Publication: |
73/73 |
International
Class: |
G01N 005/02 |
Claims
We claim:
1. An agricultural machine including a moisture measuring device
having a moisture sensor for measuring moisture of the crop
material in the machine, and a sensor state monitoring device
interconnected with the moisture measuring device.
2. A machine according to claim 1, including additional sensors,
and means for transmitting measured values from the sensors to said
sensor state monitoring device.
3. A machine according to claim 2, wherein said sensor state
monitoring device is arranged for comparing the moisture values of
the sensor state monitoring device with those transmitted by the
moisture sensor and, in case of a disparity in the values,
automatically triggers correction of the sensor state monitoring
device moisture values.
4. A machine according to claim 2, including a cab; and wherein
said sensor state monitoring device is arranged for comparing the
moisture values of the sensor state monitoring device with those
transmitted by the moisture sensor and, in case of a disparity in
the values, automatically activates a display in the cab.
5. A machine according to claim 1, wherein said sensor state
monitoring device is operative to check certain measuring states
and automatically triggers an action as a function of the detected
measuring state.
6. A machine according to claim 1, including an electronic device
into which said sensor state monitoring device is integrated.
7. A machine according to claim 1, wherein said sensor state
monitoring device is operative to select material-related
calibration curves based upon measuring material preset by an
operator.
8. A machine according to claim 1, wherein said sensor state
monitoring device is operative to select material-related
calibration curves based upon measuring material detected by the
sensor mechanism.
9. A machine according to claim 1, wherein said sensor state
monitoring device requests input.
10. A machine according to claim 1, including an additional
moisture measuring device; and wherein said sensor state monitoring
device calibrates the moisture values determined by the moisture
sensors through the moisture values of the additional moisture
measuring device.
11. A method for determining a moisture value of crop material via
a moisture measuring device in an agricultural machine, including
the steps of: sensing a moisture value in the crop material via a
moisture sensor; transmitting the moisture value to an electronic
analyzer; operating the electronic analyzer to offset the moisture
value against a calibration-dependent correction value; further
processing the offset moisture value for analysis purposes; and
determining the correction value at least, in part, as a function
of a working state of the machine.
12. A method according to claim 11, including establishing a
grain-dependent setting of the machine and using said setting as
the working state.
13. A method according to claim 11, including measuring crop
material throughput and using the same as the working state.
14. A method according to claim 11, including determining the
conveying speed of at least one conveying element of the machine
and using said speed as the working state.
15. A method according to claim 11, including determining the
position of a conveying member of the machine and using said
determination as the working state.
16. A method according to claim 11, including determining the
degree of filling of a measuring chamber and using said degree of
filling as the working state.
17. A method according to claim 11, including determining the
degree of filling of a conveying element of the machine and using
the same as the working state.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention relates generally to agricultural
machinery and, more particularly, to improvements in measuring
moisture in crops. The invention provides a moisture measuring
device as well as a method for measuring moisture of the crop
material in harvesting machines.
[0002] It is known in the art that moisture sensors can be used in
agricultural machines to precisely measure the quantity of
harvested grain, especially corn, based upon a measurement of the
harvested crop material moisture. For example German Patent
Application DE 41 05 857 provides a moisture measuring device which
uses a bypass system to continuously determine the moisture of the
harvested crop material. Furthermore, U.S. Pat. No. 5,616,851
discloses a moisture sensor which operates by accumulating a
quantity of material to be measured in a measuring chamber, then
performing the measurement and returning the measured material to
the stream of crop material prior to beginning a new measuring
cycle. Arranging continuously operating moisture sensors directly
in the path of conveying the crop material has also been attempted.
For example, a moisture sensor has been arranged in a grain tank
filling screw, instead of a spiral, or in the grain tank. These
locations for mounting the sensors were selected to be independent
of the throughput of crop material because throughput fluctuations
affect the accuracy of the moisture measurement. However, because a
sensor in the filling screw interferes with the conveying of
material and a sensor in the grain tank always allows only one
measurement per grain tank, both systems were commercially
unsuccessful.
[0003] A microwave sensor which is constructed as a smooth sensor
and is capable of determining, by use of microwaves, the moisture
content of the crop material moving past the smooth sensor is known
in the art from German Patent Application DE 196 48 126. The
microwave sensor disclosed is relatively expensive and is also
structurally elaborate, as the environment must be shielded from
the microwaves.
[0004] All moisture sensors known from the state of the art must be
calibrated to obtain accurate moisture values. There is a
distinction between calibration related to the material to be
measured, which depends upon the type of crop material, and
calibration related to processing, which is determined by the
density of the material to be measured, the quantity of material
conveyed and the conveying members. For calibration related to the
material to be measured, there are provided calibrating curves
which can be accessed by the user of the moisture measuring device.
These curves are in each case valid for certain temperatures of
material. However, the need for processing-related calibration is,
in practice, bypassed by setting up measuring points with at least
temporarily constant measurement conditions. These measuring points
do not always ensure constant measurement conditions. Therefore,
errors arise, which multiply if further processing-related error
sources of measurements, such as fouling of the sensor, are
ignored. Under such conditions, the accuracy of the moisture value
depends on the harvesting machine operator's care and understanding
for the concerns of the moisture measuring device, which cannot
always be presupposed.
[0005] It is an object of the present invention to provide an
improved moisture measuring device which minimizes the above
described drawbacks of state of the art moisture measuring
devices.
SUMMARY OF THE INVENTION
[0006] In accordance with the present invention there is provided
an agricultural machine including a moisture measuring device
having a moisture sensor for measuring moisture of the crop
material in the machine, and a sensor state monitoring device
interconnected with the moisture measuring device.
[0007] The object of the present invention is achieved by combining
the moisture measuring device with a sensor state monitoring
device. The combination of the moisture sensor with a sensor state
monitoring device makes it possible to detect error when
determining the moisture signal and to display such errors to the
driver of the harvesting machine. Furthermore, this combination
makes it possible to perform correction measures or calibration.
The calibration measures which were previously necessary can be
largely dispensed with because the sensor state monitoring device
accomplishes a good proportion of the calibration work in an
automated fashion. Moreover, the reliability of the moisture
measuring device is improved and the driver is relieved of
recurring routine work and checks.
[0008] In accordance with another aspect of the present invention
there is provided a method for determining a moisture value of crop
material via a moisture measuring device in an agricultural
machine, including the steps of: sensing a moisture value in the
crop material via a moisture sensor; transmitting the moisture
value to an electronic analyzer; operating the electronic analyzer
to offset the moisture value against a calibration-dependent
correction value; further processing the offset moisture value for
analysis purposes; and determining the correction value at least,
in part, as a function of a working state of the machine.
BRIEF DESCRIPTION OF THE DRAWING
[0009] The invention is described in more detail below with the aid
of the drawing which illustrates a practical example, and
wherein:
[0010] FIG. 1 is a schematic illustration of a grain elevator base
and equipped with moisture measuring devices.
DETAILED DESCRIPTION
[0011] FIG. 1 shows a grain elevator base 2 which may be any
construction known in the state of the art, which will aid in
understanding the manner of operation of an embodiment of the
invention to be described. A rotationally driven transverse screw
conveyor 4 with screw spirals 6 feeds crop material to the grain
elevator base 2. The crop material slides over a ramp 8 into the
bottom segment 10, where it is picked up and transported upwards by
the elevator paddles 12. The elevator paddles 12 are attached by
holding straps 14 to conveyor chains 16 which revolve around
sprockets 18.
[0012] Moisture sensors 20 are mounted below the transverse screw
conveyor 4 and on the lower side of the grain elevator base 2. The
moisture sensors 20 are in each case arranged in a housing and
determine the moisture of the crop material being conveyed over the
sensor surface. The moisture sensors 20 in the practical example
consist of an electrode 22 and an electronic device 24 which are
connected by wires 26 to the sensor state monitoring device 28. The
electronic device 24 transmits the moisture values determined by
the moisture sensors 20 to the sensor state monitoring device
28.
[0013] The sensor state monitoring device 28 consists of
microprocessors and suitable analysis software and can be directly
integrated in the electronic device 24, located at another point on
the agricultural machine, or located remotely. For description
purposes, it is shown here separately. The moisture values can be
determined continuously or periodically by the moisture sensors 20
shown in FIG. 1. Operation of the sensor state monitoring device 28
includes correcting the raw moisture values determined by the
moisture sensor 20. This is accomplished by processing the values
with the sensor state monitoring device 28, using calibration
standards. For this purpose, additional sensors 20 transmit their
sensor values to the sensor state monitoring device 28. Thus, for
example, it is possible to verify the plausibility of the measured
moisture values by reference to the values of other sensors. Thus
the sensor state monitoring device 28 can detect whether the
agricultural machine has switched on the harvesting members at all.
Sensor state device 28 can also detect whether the machine is
picking up crop material via sensors 30 on a pick-up member such as
a cutting mechanism, a treatment member such as a threshing
mechanism, a motor, a switching position of a control component, a
load measuring device or a speedometer. If the sensor state
monitoring device 28 finds, through the sensor values of the
sensors 30, that these measurement conditions are not fulfilled, it
blocks assignment of the measured moisture value to the crop
material or to a quantity of crop material. In the alternative,
under the same conditions, the sensor state monitoring device 28
may provide the moisture value with an index which, upon further
processing of the moisture value, clarifies that it does not relate
to the measurement of crop material. In addition to the analysis of
sensor signals which indirectly allow inference of the measurement
conditions at the measuring point, the sensor state monitoring
device 28 can also receive information from sensors 32 with which
the measuring state can be measured directly, such as level or
pressure sensors or quality sensors for the crop material which are
arranged in the region of the measuring point or at another point
of the agricultural machine, such as a harvesting machine. The
sensors 32 can signal different measuring states such as, for
example:
[0014] a) "No material at measuring point",
[0015] b) "There is an undefined measuring substance at the
measuring point",
[0016] c) "There is a defined measuring substance at the measuring
point",
[0017] d) "There is an additional defined measuring substance at
the measuring point", or
[0018] e) "The measuring substance at the measuring point can cause
measuring deviations",
[0019] f) "The measured material is wheat".
[0020] Depending upon these measuring states, the sensor state
monitoring device 28 can trigger different correction, display or
calibration measures. Thus it is conceivable that the status report
a) is needed for diagnostic measuring purposes or calibration
measures, b) causes the measured moisture values to be filtered
out, for example upon falling below or exceeding the permitted
measured quantity, c) signifies normal operation without further
correction or calibration measures, d) triggers an amended
correction value, e) leads to an amended indication of accuracy,
and f) accesses the calibration curves specific to the grain, such
as wheat. Instead of or in addition to a correction of the moisture
values, single measuring states or all the measuring states
determined can be displayed in the cab. The plausibility test can
also include a logic test whereby, for example, certain
combinations of sensor values are assessed as improbable at a point
in time or in a given time interval, and trigger corresponding
corrections or actions of the sensor state monitoring device 28.
Thus it would be improbable if the measured moisture value in the
harvesting machine which is stationary and empty in the measuring
region remains unchanged from the moisture value which is
determined for subsequently picked-up crop material. A constant
moisture value, irrespective of the crop material supplied, leads
one to suspect that either the moisture sensor 20 is coated by
dirt, which impairs measurement of the current crop material, or
there is a defect in the moisture sensor 20. The sensor state
monitoring device 28 can then trigger a signal in the cab or
initiate subsequent measurement or a check routine for testing the
moisture sensor 20. Furthermore, another operability defect occurs
when the moisture sensor is mounted at a location where a
fluctuating throughput quantity affects the measured moisture
value, a sensor 32 indicates fluctuating throughput quantities and
the moisture value nevertheless remains constant. In this case the
sensor state monitoring device 28 also must trigger a correction
and/or display.
[0021] In another embodiment of the invention the sensor state
monitoring device 28 scans input or memory elements 34 for certain
data. Thus, via an input or memory element 34, for example, data on
the crop material can be preset to identify the crop material as
maize, wheat, barley, etc. There can be additional particulars such
as "dry" or "wet" variety, "highly weed-infested", or
telemetrically transmitted data on the calibration or plausibility
of the moisture values. The driver of the harvesting machine can
thus, through input of the harvested material, indirectly calibrate
the moisture measuring device for the specific crop material.
[0022] An additional moisture measuring device 36 which is
connected by a wire to the sensor state monitoring device 28 is
also shown in FIG. 1. The additional moisture measuring device 36
consists of a measuring chamber which can be emptied by a movable
piston and which is mounted in a rotatably driven housing. After
filling the measuring chamber with crop material, the housing
rotates in one direction shown by the arrow so that the supply
opening to the measuring chamber is closed. During the rotation an
associated moisture sensor can determine the moisture value. The
material to be measured can be compressed in a particular manner or
weighed, and the material to be measured can be measured over a
longer time relative to the time for the moisture sensor 20, thus
improving the accuracy. The measuring chamber can be equipped with
an additional grinding device so that not only the surface
moisture, but the moisture of the whole of the crop material can be
determined, which also maximizes the accuracy of the determination
of the measured value. The moisture measuring device 36 can also
use a heating technique, for example infrared drying, in order to
measure the quantity of water evaporating. The moisture value of
the additional moisture measuring device 36, which is determined as
accurately as possible, can then be compared by the sensor state
monitoring device 28 as a calibrating value with the moisture value
determined by the moisture sensor 20. Furthermore, in case of
deviations, a correction factor can be determined.
[0023] The method according to the invention provides for
determining a correction value which is, at least in part, a
function of the working state of the harvesting machine. Working
states of the harvesting machine considered may include the
fruit-dependent setting, the throughput of material, the speed of
conveying, the position of the conveying member or the degree of
filling of the measuring chamber or conveying member.
[0024] The embodiment described herein, disclosing conveying
elements for a combine, can be applied without great effort to
other harvesting machines such as forage harvesters, balers, cutter
bars, loading trucks and other agricultural machines. Further, the
proposed device and method can basically be realized using all
known sensor technologies for moisture measurement. It is within
the capability of one skilled in the art to make advantageous
alterations and additions to the application.
[0025] Other objects, features and advantages will be apparent to
those skilled in the art. While preferred embodiments and steps of
the present invention have been illustrated and described, this has
been by way of illustration and the invention should not be limited
except as required by the scope of the appended claims.
* * * * *