Method and apparatus for removing a quantity of fodder from a stock thereof

The invention relates to a method for removing a quantity of fodder from a stock thereof according to the preamble of claim 1, as well as to an apparatus for removing fodder from a stock thereof according to the preamble of claim 7.

Such methods and apparatuses are known in various embodiments thereof, see for example <patcit id="pcit0001" dnum="EP1062861A"><text>EP-A-1 062 861</text></patcit> and <patcit id="pcit0002" dnum="DE20104426U"><text>DE-U-201 04 426</text></patcit>. When a quantity of fodder is being removed from a stock thereof, it is important that the correct quantity by weight is removed in order to prevent loss of fodder. It is known to fit an apparatus of the aforesaid kind with an electronic weighing system, by means of which the fodder present in the container can be weighed.

<patcit id="pcit0003" dnum="US4595125A"><text>US 4, 595, 125</text></patcit> discloses a method for continuously dispensing fodder using rollers. For each revolution of the rollers a specific volume of material is deposited on a conveyor. Subsequently, the removed volume is weighed. If the determined weight is too high or too low, the conveyor speed is adjusted in order to transport exactly the desired amount of fodder.

<patcit id="pcit0004" dnum="GB2089315A"><text>GB 2,089,315</text></patcit> discloses a silage handling unit comprising a depth determining structure. The structure determines the maximum depth of a slice of silage to be removed.

The known apparatuses have this drawback that it is not possible to determine the weight before the fodder is separated from the stock of fodder.

The object of the invention is to provide a method and apparatus of the kind referred to in the introduction, in which this drawback is obviated in a simple manner.

According to the invention this object is achieved by a method according to claim 1.

The invention is based on the perception that it is possible, even when using simple means, to determine the volume of a quantity of fodder to be separated before the fodder is separated from the stock. In this way the removal of an excessive quantity of fodder from the stock of fodder is prevented.

A suitable apparatus for implementing the method according to the invention is characterized by claim 7.

The invention will now be explained in more detail with reference to the drawing, which shows a few very schematic embodiments of the apparatus according to the invention.

<figref idref="f0001">Fig. 1</figref> shows an example of an apparatus not falling under the invention, in which the removing means are embodied as a cutting device.

<figref idref="f0002">Fig. 2</figref> shows an embodiment of the apparatus according to the invention, in which the removing means are likewise embodied as a cutting device, and in which sensors for measuring the volume to be separated are used.

<figref idref="f0003">Figs. 3 and 4</figref> show an embodiment corresponding to <figref idref="f0002">Fig. 2</figref>, in which sensors for determining the volume of the separated quantity of fodder during the removal thereof are used.

<figref idref="f0004">Figs. 5 and 6</figref> are a top plan view and a side elevation, respectively, of an embodiment corresponding to <figref idref="f0002">Fig. 2</figref>, which is fitted with a sensor for determining the profile of the front wall of the stock of fodder.

<figref idref="f0005">Fig. 7</figref> shows an embodiment of the apparatus according to <figref idref="f0004">Fig. 5</figref>, in which two sensors are used for scanning the profile of the front wall of the stock of fodder.

<figref idref="f0006">Figs. 8</figref> and <figref idref="f0007">9</figref> show an embodiment of the apparatus according to the invention, which uses one or two distance sensors whose measuring direction can be pivoted.

In <figref idref="f0001">Fig. 1</figref> there is shown an apparatus for removing fodder from a stock thereof, in this case a stock of silage 1, which apparatus comprises removing means consisting of a removing jaw 2 and a loading flap 3 for receiving removed fodder. In the illustrated embodiment, the removing jaw 2 is embodied as a cutting jaw provided with cutting blades 4. Said cutting blades may or may not be driven. Alternatively, double cutting blades may be used, in which case one blade, or both, may be driven.

The removing jaw 2 is pivotally connected to the loading flap 3, it can be pivoted with respect to the loading flap 3 by means of cylinder-piston assemblies 5. The removing means 2,3 can be hitched to the front or to the rear of a tractor. It is noted that the construction of the apparatus as described above is known per se and does not form the subject matter of the present patent application. For a more detailed description, reference is made to the aforesaid publications <patcit id="pcit0005" dnum="EP1062861A"><text>EP-A-1 062 861</text></patcit> and <patcit id="pcit0006" dnum="DE20104426U"><text>DE-U-201 04 426</text></patcit>.

The removing jaw 2 of the apparatus that is shown in <figref idref="f0001">Fig. 1</figref> is provided with a scale division 6 (schematically indicated) for the working width of the removing jaw. Preferably, said scale division 6 is present on the inner side of the removing jaw 2 so as to enable easy reading thereof. As will be explained below, the volume of a quantity of fodder 7 to be separated from the stock of fodder 1 can easily be determined by means of the scale division 6. When using the apparatus described herein, the loading flap 3 is moved under the stock of fodder with its bottom plate 8 until one of the side walls 9, or both side walls, abut(s) against the front wall 10 of the stock of silage 1. Thus the maximum depth of the block 7 to be cut out is determined. The driver of the tractor (not shown) can now position the apparatus described herein with respect to the stock of silage, using the scale division, in such a manner that a block 7 having the desired width can be cut from the stock. In this way the volume of the quantity of silage to be separated is determined.

If the apparatus described herein is provided with a weighing computer, said weighing computer will be arranged for establishing a reference value, in particular the weight of a specific volume of fodder. To that end, a maximum block of silage, i.e. a block having a maximum height, a maximum working depth and a maximum working width, is cut from the stock 1 by means of the apparatus described herein, and the weight of such a block having a maximum volume is determined by the weighing computer. When the apparatus is subsequently used for removing a desired quantity of fodder expressed as a weight, said weight is input via input means (not shown), and the computer will display a volume to be removed on a display screen (likewise not shown). For example, if the maximum block weighs 1100 kilograms and the desired quantity is 1650 kilograms, the computer will indicate on the display that 150%, or 1.5 times the maximum volume is to be cut out. If a block of 1000 kilograms is cut out in the first removing cycle, the computer will display a value of 59,09% on the display screen as the volume yet to be separated. Using the scale division, the driver can easily manoeuvre the apparatus in such a manner with respect to the stock 1 that about 60% of the maximum volume will be removed.

In those cases in which the composition of the stock of silage varies, a specific volume of fodder may be removed from the stock at certain intervals for the purpose of establishing a new reference value by measuring the weight of the removed volume. Furthermore it is possible to establish different reference values when fodder is removed from different stocks of silage, which reference values are used when removing a desired weight from the associated stock of fodder.

<figref idref="f0002">Fig. 2</figref> shows an embodiment of the apparatus according to the invention, which is fitted with the same removing means 2, 3. In this case the removing means 2, 3 is mounted on a fodder mixing cart 11, which will not be described in more detail herein. In this embodiment, the volume of the quantity of fodder to be separated is measured by means of sensors 12-15 (schematically indicated), for example laser telemeters. The sensor 12 is arranged for measuring the depth of the block to be cut out, the sensor 13 is arranged for measuring the height of the block to be cut out, whilst the sensors 14, 15 measure the width of the block to be cut out. The sensors 12-15 are connected to the computer (not shown), which is capable of computing the volume of the block to be cut out on the basis of the measuring signals from the sensors 12-15. The advantage of this embodiment is that it is possible to vary not only the width dimension but also the depth and height dimensions of the block to be cut out, so as to cut out a specific, desired volume.

Also with this embodiment it is possible to cut out a volume at certain intervals so as to measure the weight of said volume for the purpose of registering a reference value in the computer.

<figref idref="f0003">Figs. 3 and 4</figref> schematically show another embodiment of the apparatus according to the invention, which mainly corresponds to the apparatus that is shown in <figref idref="f0002">Fig. 2</figref>. In this case, two sensors 16 are used instead of the sensors 12-15, which sensors measure the volume of the cut-out portion when cutting fodder from the stock 1, so that the computer can compute whether the desired weight is reached yet. As a result, cutting can be stopped at a specific height as soon as the desired weight is reached.

<figref idref="f0004">Figs. 5 and 6</figref> schematically show an embodiment of the apparatus according to the invention, in which a distance sensor 16 is used for scanning the profile of the front wall 10 of the stock of fodder. The measuring direction of the distance sensor 16 is indicated by a dashed line 17 in <figref idref="f0004">Figs. 5 and 6</figref>. Said measuring direction 17 includes an angle with the longitudinal axis of the fodder mixing cart 11 or with the direction of movement 18 of the fodder mixing cart 11 when said to cart is being moved to the stock of fodder 1 by a tractor (not shown). As a result of this configuration, the distance sensor 16 scans the operating area behind the removing means 2, 3 while the fodder mixing cart 11 is being moved in rearward direction. The distance sensor 16 is connected to the computer (not shown) with which the fodder mixing cart 11 is equipped. The computer can determine the cross-sectional profile of the front wall 10 of the stock of fodder on the basis of the signal from the distance sensor 16. Based on said cross-sectional profile, the known removing range of the removing means 2, 3 and the height of the stock of fodder, the computer can calculate the volume of the fodder that can be cut from the stock by the removing means 2, 3. The removing range of the removing means 2, 3, which is defined by the maximum removing width and removing depth, is indicated by a dashed line 19 in the top plan view of <figref idref="f0004">Fig. 5</figref>.

It is noted the stepped profile of the front wall 10 may render it impossible for the distance sensor 16 to scan all parts of said profile. The missing information can be determined by the computer on the basis of a suitable algorithm. Alternatively, the embodiment that is shown in <figref idref="f0005">Fig. 7</figref> may be used, in which two distance sensors 16 having measuring directions 17 are used. For the rest, the embodiment of <figref idref="f0005">Fig. 7</figref> corresponds to the embodiment that is shown in <figref idref="f0004">Figs. 5 and 6</figref>.

<figref idref="f0006">Figs. 8</figref> and <figref idref="f0007">9</figref> show an embodiment of the apparatus described herein that substantially corresponds to the embodiments as shown in <figref idref="f0004 f0005">Figs. 5-7</figref>. In the embodiment according to <figref idref="f0006">Figs. 8</figref> and <figref idref="f0007">9</figref>, the removing means 2, 3 is provided with two distance sensors 20, the measuring direction 21 (indicated by a dashed line) of which can be pivoted for the purpose of scanning the profile of the front wall 10 of the stock of fodder 1. Said pivoting of the measuring direction 21 can be achieved, for example, in that the distance sensor 20 is pivotally connected to the loading flap 3. In this embodiment, the fodder mixing cart 11 may first be positioned against the front wall 10 of the stock of fodder 1 with its loading flap, after which the profile of the front wall 10 is scanned by the distance sensors 20. On the basis of the signals received from the distance sensors 20, the computer can calculate the volume of the fodder to be removed in the same manner as in the embodiment of <figref idref="f0004 f0005">Figs. 5-7</figref>. In this case it is also possible, of course, to use only one distance sensor 20, and to calculate the volume of the parts that cannot be scanned, for example due to the fact that the profile is stepped, on the basis of a suitable algorithm. Instead of using two distance sensors, it is furthermore possible to use one distance sensor 20 which employs two distance scanning beams, one beam of which scans the profile directly, whilst the other beam scans the profile from the other direction via an optical module mounted at the position of the other sensor 20.

The removing means 2,3 can be adjusted in height with respect to the fodder mixing cart 11 in a usual manner by means of a cylinder-piston assembly 23 (see <figref idref="f0002">Fig. 2</figref>). With the apparatus described herein it is important that the height of the pivoting point 22 of the removing jaw is known, because said height determines the course of the cutting curve described by the removing jaw 2 in comparison with the preceding cutting curves. To that end a height gauge (not shown) may be provided, which height gauge is connected to the computer, so that the computer can take the height of the pivoting point 22 into account when calculating the volume of the part of the stock of fodder 1 that is to be removed. Alternatively, the height gauge may be used by the computer for positioning the loading flap 3 at the same height relative to the fodder mixing cart 11 with every pass of the removing means 2, 3. Said adjustment of the height may also be carried out by the user of the apparatus, of course.

It is furthermore noted that the fodder mixing cart 11 of the embodiment of <figref idref="f0001">Fig. 1</figref> and <figref idref="f0004 f0005 f0006 f0007">Figs. 5-9</figref>, too, may be equipped with a sensor for measuring the height of the stock of fodder 1. Said sensor is preferably connected to the computer, so that the height of the stock of fodder 1 need not be input manually.

From the foregoing it will be apparent that the invention provides a method and apparatus by means of which a desired quantity by weight of fodder can be separated from a stock thereof by determining the volume of the quantity of fodder that is to be separated or that has been separated. It will be apparent that the invention may be implemented with any type of removing means. The type of removing means 2, 3 that is described herein is merely shown by way of example, therefore.

The invention is not limited to the embodiments as described above, which can be varied in many ways within the scope of the invention as defined in the claims.