GB2387098A

GB2387098A - Method and apparatus for measuring grain loss

Info

Publication number: GB2387098A
Application number: GB0207793A
Authority: GB
Inventors: Stephen Allen
Original assignee: Individual
Current assignee: Individual
Priority date: 2002-04-04
Filing date: 2002-04-04
Publication date: 2003-10-08
Also published as: GB0207793D0

Abstract

A method and apparatus for determining the yield loss of grain during combine harvesting comprising the steps of sampling the deposited crop material by placing a sampling means 10 on the ground during harvesting by the combine harvester 12 behind the harvesting header and under the body of the harvester 12, The means 10 receives deposited crop material and lost grain as the rear end of the harvester 12 passes over it. The grain yield loss is determined on the basis of the deposited grain in the sample. A winnowing apparatus 50 is disclosed for separating chaff from lost grain collected by the sampling means 10.

Description

:6 -1 METHOD AND APPARATUS FOR MEASURING GRAIN LOSS

This invention relates to a method and apparatus for determining grain loss from harvesting machines such as 5 combine harvesters.

It is a well known fact that harvesting machines, such as combine harvesters, do not put into the grain tank all the grain which is separated from the crop. Some of the grain falls on the ground with the straw from the rear end 10 of the straw walkers of the combine. This is because the grain has been carried along on the straw, and has not shaken through so as to fall into the grain-collecting troughs, and thus be transferred to the shaker shoe for winnowing. 15 As might be expected, the faster the combine harvester goes, the greater is the grain loss, and systems have been devised to measure the grain loss and indicate it to the driver of the combine, so that he can control the ground speed accordingly, and strike a reasonable balance between 20 speed and grain loss.

One approach to the question of judging combine harvester grain losses would be for the driver to stop the machine periodically and to inspect the material deposited on the ground by the harvester in the portion of the field

25 just harvested. Certain difficulties arise in this connection including the fact that the lost grain is usually hidden underneath the swath of straw and in any case the extent of the losses is a matter for visual judgement by the driver or a colleague and is not 30 quantitative in any way, whereas commercial combine harvester operations must be based upon the proper balance between harvesting speed and grain loss in a quantitative way. An example of such a grain loss monitor is a device 35 providing a sensor located just a little beyond the end of

( -2- the straw walkers, and well positioned to intercept a proportion of the grain coming over the end of the straw walkers, and which operates to provide on an acoustic basis, a signal generated by the impact of the grains with 5 an acoustic tube, and giving a measure of the amount of grain loss.

Such devices have had a degree of success, but something simpler and more direct is called for in relation to one sector of the combine harvester market.

10 Also, it is important that existing grain loss monitors are properly calibrated and tested so that they can be relied upon by the operators.

Therefore, we have identified a need for a method and apparatus for measuring grain loss in harvesting machines 15 and for calculating the yield loss from the grain loss measurement which is capable of providing a quantitative measure of such losses while not involving the provision of extra equipment on the combine harvester itself.

According to the invention there is provided a method 20 and apparatus as defined in the accompanying claims.

In an embodiment of the invention, the yield loss of grain during combine harvesting is determined by sampling the deposited crop material by placing a sampling means on the ground during harvesting by said combine harvester 25 behind the harvesting header and under the body of the harvester to receive said deposited crop material and said lost grain as the rear end of the harvester passes over it, and determining the grain yield loss on the basis of the deposited grain in the sample. Means may be provided for 30 separating the lost grain from the chaff. The separation of the lost grain from the deposited material may comprise a first step of removing the coarse deposited crop material such as straw from the sample and a further step of separating the lost grain from the chaff.

35 In another embodiment, measuring means may be provided

for measuring a quantity of lost grain in the sample to determine the yield loss of grain. Suitable measuring means may comprise a measuring jar, a weighing device or a grain counting device.

5 In another embodiment of the invention, the method may comprise the step of providing a measure of the width of the cutter bar of the combine harvester, providing a measure of the quantity of lost grain in the sample, and providing a means for calculating the grain yield loss, the 10 method further comprising the step of calculating the yield loss of grain on the basis of the aforesaid measures. The yield loss of grain may further be calculated on the basis of an additional measure of the harvesting velocity.

After sampling the deposited crop material, separating 15 the deposited grain and measuring the quantity of grain, the yield loss of grain may be calculated from the measured quantity. In this way, a direct measurement of the deposited grain as part of the unwanted deposited crop material may be used as the basis for calculating the yield 20 loss of the combine harvester for a specific harvesting velocity. In yet another embodiment, the yield loss may be calculated on the basis of compiled yield loss data which present the loss of grain as a function of the measured 25 quantity of deposited grains and the cutter bar size of the combine harvester. These data may be tabulated.

Alternatively, the data may be available from a suitable computer system. Preferably, grain loss is calculated in tons per acre or as a percentage of the tons of grain 30 harvested per acre.

In another embodiment, there is provided a method of calibrating a yield loss detection system or yield loss monitor of a combine harvester by determining the yield loss of grain in accordance with a method as hereinbefore 35 described. The determined quantity of deposited grain or

-4 alternatively the calculated yield loss may be used to calibrate a built-in yield loss detection system such as the system as herein before described using the acoustic detection means.

5 In this way, the combine operator may accurately calibrate or adjust the yield loss detection system to the particular harvesting conditions and properties of the grain or wheat that is harvested.

In yet another embodiment, there is provided a method 10 of selecting the harvesting velocity of harvesting machine to optimize the overall yield of the harvesting process.

The overall yield in this respect represents the maximum quantity of harvested grain whereby grain yield losses are reduced as much as possible, and whereby the operational 15 velocity is of an acceptable level to ensure that harvesting proceeds in an economic time space. As discussed, both the harvesting efficiency and the yield loss are dependent on the harvesting velocity of the machine. Obviously, there is a trade off between harvesting 20 efficiency whereby grain yield losses are substantially reduced and the combine harvester operation costs which are usually dependent upon the amount of time the machine is hired or in operation.

In yet another embodiment of the invention there is 25 provided an apparatus for determining the yield loss of grain during combine harvesting. The apparatus may comprise means for sampling crop material as deposited by a combine harvester. The sampling means may comprise a grain collecting device adapted to be placed on the ground behind 30 the harvesting header and under the body of the harvester to receive said lost grain during harvesting as the rear end of the harvester passes over it. The grain collecting device may comprise means for adapting the width of said device to enable receiving all deposited crop material and 35 lost grain across the width of the rear end of the combine

- -5- harvester. In a preferred embodiment the apparatus may comprise separation means for separating the lost grain from the deposited crop material. The grain may be separated from 5 the deposited material in two or more stages, whereby in a first stage, the coarse material (such as straw) is removed from the deposited material, and in a further or second stage the chaff is removed from the grain. This allows the quantity of deposited grain in the sample to be accurately 10 determined and measured. The separation means may comprise a winnowing apparatus for removing the chaff from the grain. In this way, the operator or contractor may select the best suitable harvesting velocity on the basis of the 15 measurement of grain loss which is carried out before the harvesting operation takes place. This reduces the grain loss as much as possible whilst allowing the harvesting velocity to be as high as possible.

In another embodiment, the apparatus may comprise 20 means for measuring a quantity of grain. The means may comprise a weighing means (such as a scale or balance):, a: volumetric measuring means (such as a measuring jar), a grain counting means or combinations of the aforesaid measuring means.

25 In yet another embodiment of the invention, the apparatus may comprise a means for calculating the grain yield loss on the basis of a measure of the width of the cutter bar of the combine harvester and a measure of the quantity of lost grain in the sample. The calculating means 30 may comprise a computer, a table, a calculator and/or combinations of the aforesaid calculation means.

In yet another embodiment of the invention there is provided a winnowing apparatus for removing the chaff from the deposited material to expose the grain, the apparatus 35 comprising a container for holding the deposited material

and an airflow device for providing an air flow. The container further comprises a delivery means in the form of an air-pervious screen to allow the air flow inside the body of the grain in the container so as to remove the 5 chaff from the grain by means of the airflow. A suitable delivery means is a mesh which may be provided in the bottom of the container. Preferably, the container is open at the top to allow the chaff to be conveniently removed.

The weight of the grain ensures that the grain is not 10 removed whilst the chaff is removed.

The winnowing apparatus may preferably be handheld which enables the apparatus to be taken to any desired location. During operation of the air flow, the container may be shaken or stirred to promote the exposure of the 15 grain to the air flow and to enhance removal of chaff. The container may further comprise measuring means for measuring the quantity of grain inside the container. For example, the measuring means may comprise a suitable scale for measuring the quantity of grain.

20 In yet another embodiment of the invention the sampling means may comprise a deposited crop collecting tray, the width of the tray being adaptable to the width of the depositing means or straw walkers of the combine harvester. 25 There is thus provided a method of determining the yield loss of grain, an apparatus for determining the yield loss of grain and a winnowing apparatus as described in any of the accompanying claims.

In an embodiment of the invention the grain loss 30 measurement apparatus comprises grain separation means adapted to facilitate the effective separation of grains from other crop materials such as straw and chaff whereby the then-separated grain can be quantitatively assessed in a time and accuracy-effective manner.

35 In the embodiments, several stages of grain separation

are involved, the principal ones being separation from straw and separation from chaff.

A particular aspect of the invention relates to the provision of a method and apparatus for separation of grain 5 from chaff without requiring the usual process in which a cascade of grain is subjected to a winnowing blast of air, as occurs in the shaker shoe of the combine harvester.

In the method and apparatus of the embodiments, the method for separation of grain from the chaff involves the 10 provision of grain holding means in association with air flow means adapted to direct an air flow into and throw the grain held in the grain holding means.

It is an important aspect of the embodiments of this' invention that means is provided whereby the quantity of 15 grain lost by the harvesting machine can be determined with sufficient accuracy, and without unacceptable errors being introduced by the presence of the other crop materials which are inevitably present in the harvesting operation, such as chaff and straw. The embodiments of the invention 20 provide means for removal of unwanted crop material by employing separation steps. These separation steps maybe; employed in relation to both a first grain collecting stage of the process, and a subsequent grain-receiving and separating step. In the first of these steps, the 25 separation is of grain from straw, and in the second of these steps, the separation is of grain from chaff.

In relation to the separation of grain from chaff, the described embodiment of the invention avoids the need for conventional spaceconsuming arrangement adopted in the 30 shaker shoe of a combine harvester, and elsewhere, in which the separated grain is caused to cascade through a curtain of air which serves to carry away the chaff mixed with the grain. In the embodiment, the arrangement is adapted to provide container means for the grain collected in a given 35 sampling or measurement operation, in combination with an

-8- air flow device such as a fan, which is mounted in relation to the container so as to deliver the corresponding air flow to the container through an air-pervious screen device adapted to retain grain while permitting air flow into the 5 body of grain within the container.

In this way, the embodiment provides a device whereby collected grain is subjected to an air flow within the container itself, whereby according to the rapidity of the air flow, chaff and the like can be entrained and removed.

10 In the embodiment, the chaff removing device is adapted to provide the function of allowing the grain to be at least partially dispersed, or uplifted by the user during the chaff removal step in which a shaking action may be adopted whereby the grain within the container device is 15 subjected to a degree of cascading action while being subjected to the air flow from the airflow device or fan.

In this way, and by virtue of the use of a grain collecting device in combination with an air flow admission device, there is provided the practical function of chaff 20 separation by means of a simple hand-held device, whereby this device can be combined in a compact practical item of apparatus, with a grain collection device to provide a quantitative means for determining grain loss.

In relation to the chaff removal process, the 25 embodiment requires air flow means, though the manner in which the air flow is applied to the grain itself may be subjected to variation. In the illustrated embodiment, a quantity of grain is held in a container, which incorporates an air admission device in the form of a 30 screen, together with the provision of an air exit or outlet device. In the embodiment, the air admission device comprises a screen adapted to retain the grain while admitting an air flow. It will be understood that the functional step required is to provide by means of the 35 apparatus a device whereby the grain may be subjected to

- 9 - the airflow in a manner permitting the entrainment and escape of the chaff while not causing or readily allowing loss of any grains. Thus, the dispersing and/or uplifting of the grain so as to produce a partial cascading action in 5 relation to the airflow may be induced by means of a shaking action by the user, or some degree of air blast action by the air flow, are aspects of the function of the chaff separation device.

In relation to the initial grain collection function, 10 the embodiment provides a grain collecting device in the form of a tray or the like, adapted to be manually placed by the user in position on the ground during harvesting operations, so as to be passed over by a harvester during harvesting operations, so that grain not removed from the 15 crop material discharged by the harvester will be collected by the collecting device over a known area of ground, whereby, that amount of grain can be determined in terms of grain loss per unit area.

The invention will now be described by way of example 20 only and with reference to the accompanying drawings in which: Figure 1 presents a diagrammatic plan view of a combine harvester and a sampling means in an embodiment of the invention; 25 Figure 2 presents a diagrammatic perspective view of a sampling means in the embodiment of Figure 1; Figure 3 presents a diagrammatic cross-sectional view of the sampling means according to the embodiments of Figures 1 and 2; 30 Figure 4 presents a diagrammatic view of a separation means in the form of a winnowing apparatus and a perspective view of the sampling means according to the embodiment of Figures 1, 2 and 3; Figure 5 presents a diagrammatic cross-sectional view 35 of the separation means according to the embodiment of

- 1 0 Figures 1 to 4; Figure 6 presents a diagrammatic cross-sectional view of a winnowing apparatus according to another embodiment of the invention; 5 Figure 7 presents a grain loss calculation chart in accordance to yet another embodiment of the invention, and A sampling means in the form of a crop collecting tray is adaptable to the width of the crop depositing means or straw walkers of a combine harvester 12. The tray 10 10 consists of individual parts 14, 16, 18 which are inter connectable to form a collecting tray of a suitable width which enables all deposited material from the combine harvester 12 to be collected. The tray 10 has a generally flat planar surface for receiving the material and an 15 upstanding rim 20 which facilitates the material to be contained within the tray as is shown in Figure 3. To remove the material, the tray 10 can be conveniently inclined or tipped so that the material slides off the generally plainer surface of the tray into a suitable 20 holder as is shown in Figure 4.

In use, the tray 10 is adapted to the width of the straw walkers of the combine harvester 10 and located onto the ground behind the harvesting header or cutter bar and under the body of the harvester to receive the deposited 25 crop material and the lost grain whilst the harvester is in operation. Usually the tray is positioned by hand. The material is deposited onto the tray as the rear end of the harvester passes over it. The deposited grain 21 then sits onto the planar surface of the tray, whereas the other crop 30 materials such as straw 22 sits on top as is shown in Figures 3a and 3b. The straw material 22 is removed by hand and the deposited grain 21 remains as is shown in Figure 3.

This deposited grain is then transferred from the tray 10 into a winnowing apparatus 30 which is adapted to separate 35 the grain from the chaff.

The winnowing apparatus or winnowing container 30 comprises a reservoir for retaining the deposited grain and an airflow device 34 for creating an airflow through the reservoir 32. The reservoir 32 further comprises an air 5 pervious screen or mesh which retains the deposited grain inside the reservoir 32 and which allows air to permeate through the reservoir. In this way, the air flow removes the chaff from the deposited grain so that chaff free grains are retained. To enable the chaff to be conveniently 10 removed the reservoir 32 has an open top so that the chaff can blow away freely as is shown in Figure 3b. In use, the deposited grain is situated inside reservoir 32 and the air fan is switched on. This enables the air stream to enter the reservoir and to remove the chaff from the grain.

15 Removal of the chaff may be further aided by shaking or otherwise perturbing or moving the grain contained inside the reservoir 32.

Figure 6 present a detailed cross-sectional view of a winnowing apparatus 50. The apparatus 50 comprises an 20 airflow device 52 and a reservoir 54 comprising a mesh screen bottom. The apparatus further comprises a cowl 56 which guides the airflow through the reservoir 54 to remove chaff away from the grain through the opening in the reservoir 54. To facilitate transport and operation of the 25 winnowing apparatus handles 58 are provided. The reservoir section 54 of the winnowing apparatus is releasably connectable to the airflow device 52 by means of interconnecting means 60. The airflow device comprises a motor 62 which is suspended within a housing with brackets 30 65. The motor 62 is provided with a suitable fan 66. The apparatus further comprises a switch 68 and a power supply 70 for powering the fan 64. The power supply 70 is provided on a base plate 74. A power socket 72 is provided for recharging the power supply.

35 In use, the reservoir 54 is filled with the deposited

-12 grain and is located onto the airflow device 52 by a twisting lock action. The fan 64 is powered and the airflow enters the reservoir 54 thereby removing the chaff from the grain. After removal of the chaff from the grain, the grain 5 is transferred to a suitable measuring jar or suitable weighing means for measuring the quantity of deposited grain. From this, the quantity of deposited grain is determined. Furthermore, the yield loss of grain may be calculated from the measured quantity of lost grain in the 10 sample.

To facilitate the calculation of- the yield loss of grain as deposited by a combine harvester, the table of Figure 7 has been compiled. This table is largely self explanatory. For a given cutter bar size or header size of 15 the combine harvester and a given (measured) quantity of lost deposited grains in the sample, the yield loss in kilograms per acre or as a percentage of the yield can be readily found.

Claims

-13 CLAIMS

1. A method of determining the yield loss of grain during combine harvesting comprising the steps of 5 providing means for sampling crop material as deposited by a combine harvester, wherein, said sampling means comprise a grain collecting device adapted to be placed on the ground to receive said lost grain, 10 the method further comprises the steps of sampling the deposited crop material by placing said device on the ground during harvesting by said combine harvester behind the harvesting header and under the body of the harvester to receive said deposited crop material and said lost grain 15 as the rear end of the harvester passes over it, and determining the grain yield loss on the basis of the deposited grain in the sample.

2. A method of determining the yield loss of grain during 20 combine harvesting comprising the steps of sampling the deposited crop material by placing a sampling means on the ground during harvesting by said combine harvester behind the harvesting header and under the body of the harvester to receive said deposited crop material and said lost grain 25 as the rear end of the harvester passes over it, and determining the grain yield loss on the basis of the deposited grain in the sample.

3. A method according to claim 1 or 2, wherein the method 30 comprises the step of providing means for separating the lost grain from the chaff, said method further comprising a first step of removing the coarse deposited crop material such as straw from the sample and a further step of separating the lost grain from the chaff.

-14

4. A method according to any of the preceding claims, wherein the method comprises the step of providing measuring means for measuring a quantity of grain, said method further comprising the step of measuring the 5 quantity of lost grain in the sample to determine the yield loss of grain.

5. A method according to claim 4, wherein the method comprises the step of providing a measure of the width of 10 the cutter bar of the combine harvester, providing a measure of the quantity of lost grain -in the sample, and providing a means for calculating the grain yield loss, the method further comprising the step of calculating the yield loss of grain on the basis of the aforesaid measures.

6. A method of calibrating a yield loss monitoring system of a combine harvester by determining the yield loss of grain in accordance with a method according to any of the preceding claims.

7. A method of selecting the harvesting velocity of a harvesting machine to optimise the grain yield, said method comprising the steps of determining the yield loss of grain for one or more 25 operating velocities of the harvesting machine in accordance with a method of any of claims 1 to 6 to establish the yield loss as a function of harvesting velocity, selecting a preferred harvesting velocity whereby the 30 yield loss is sufficiently low and the harvesting velocity is sufficiently high so as to strike a balance between harvesting velocity and grain yield.

8. An apparatus for determining the yield loss of grain 35 in accordance with a method of any of claims 1 to 7.

-15

9. An apparatus for determining the yield loss of grain during combine harvesting comprising means for sampling crop material as deposited by a combine harvester, wherein 5 said sampling means comprise a grain collecting device adapted to be placed on the ground behind the harvesting header and under the body of the harvester to receive said lost grain during harvesting as the rear end of the harvester passes over it.

10. An apparatus according to claim 9, wherein the grain collecting device comprises means for adapting the width of said device to enable receiving all deposited crop material and lost grain across the width of the rear end of the 15 combine harvester.

11. An apparatus according to claim 9 or 10, wherein the apparatus comprises means for separating the lost grain from the chaff.

12. An apparatus according to any of claims 9 to 11, wherein the apparatus comprises means for measuring a quantity of grain, said means comprising a weighing means, a volumetric measuring means, grain counting means or 25 combinations of the aforesaid measuring means.

13. An apparatus according to any of claims 9 to 12, wherein the apparatus comprises a means for calculating the grain yield loss on the basis of a measure of the width of 30 the cutter bar of the combine harvester and a measure of the quantity of lost grain in the sample, said calculating means comprising a computer, a table, a calculator and/or combinations of the aforesaid calculation means.

35

14. An apparatus according to any of claims 9 to 13,

-16 wherein the separation means comprises a winnowing apparatus for removing the chaff from the grain.

15. A winnowing apparatus for removing the chaff from the 5 deposited material to expose the grain, the apparatus comprising a container for holding the deposited material, and an air flow device for providing an air flow, the container further comprising means for delivering the air flow into body of the grain within the container to remove 10 the chaff from the grain, the delivery means comprising an air-pervious screen.

16. A winnowing apparatus according to claim 15, wherein the container is releasable mountable onto the air flow 15 device.